Thomas Gleixner | 1a59d1b8 | 2019-05-27 08:55:05 +0200 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
Lee Jones | ffbed07 | 2021-03-30 17:44:58 +0100 | [diff] [blame] | 2 | /* |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 3 | * eCryptfs: Linux filesystem encryption layer |
| 4 | * In-kernel key management code. Includes functions to parse and |
| 5 | * write authentication token-related packets with the underlying |
| 6 | * file. |
| 7 | * |
| 8 | * Copyright (C) 2004-2006 International Business Machines Corp. |
| 9 | * Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com> |
| 10 | * Michael C. Thompson <mcthomps@us.ibm.com> |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 11 | * Trevor S. Highland <trevor.highland@gmail.com> |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 12 | */ |
| 13 | |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 14 | #include <crypto/hash.h> |
| 15 | #include <crypto/skcipher.h> |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 16 | #include <linux/string.h> |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 17 | #include <linux/pagemap.h> |
| 18 | #include <linux/key.h> |
| 19 | #include <linux/random.h> |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 20 | #include <linux/scatterlist.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 21 | #include <linux/slab.h> |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 22 | #include "ecryptfs_kernel.h" |
| 23 | |
Lee Jones | ffbed07 | 2021-03-30 17:44:58 +0100 | [diff] [blame] | 24 | /* |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 25 | * request_key returned an error instead of a valid key address; |
| 26 | * determine the type of error, make appropriate log entries, and |
| 27 | * return an error code. |
| 28 | */ |
Michael Halcrow | cd9d67d | 2007-10-16 01:28:04 -0700 | [diff] [blame] | 29 | static int process_request_key_err(long err_code) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 30 | { |
| 31 | int rc = 0; |
| 32 | |
| 33 | switch (err_code) { |
Eric Sandeen | 982363c | 2008-07-23 21:30:04 -0700 | [diff] [blame] | 34 | case -ENOKEY: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 35 | ecryptfs_printk(KERN_WARNING, "No key\n"); |
| 36 | rc = -ENOENT; |
| 37 | break; |
Eric Sandeen | 982363c | 2008-07-23 21:30:04 -0700 | [diff] [blame] | 38 | case -EKEYEXPIRED: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 39 | ecryptfs_printk(KERN_WARNING, "Key expired\n"); |
| 40 | rc = -ETIME; |
| 41 | break; |
Eric Sandeen | 982363c | 2008-07-23 21:30:04 -0700 | [diff] [blame] | 42 | case -EKEYREVOKED: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 43 | ecryptfs_printk(KERN_WARNING, "Key revoked\n"); |
| 44 | rc = -EINVAL; |
| 45 | break; |
| 46 | default: |
| 47 | ecryptfs_printk(KERN_WARNING, "Unknown error code: " |
Joe Perches | 888d57b | 2010-11-10 15:46:16 -0800 | [diff] [blame] | 48 | "[0x%.16lx]\n", err_code); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 49 | rc = -EINVAL; |
| 50 | } |
| 51 | return rc; |
| 52 | } |
| 53 | |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 54 | static int process_find_global_auth_tok_for_sig_err(int err_code) |
| 55 | { |
| 56 | int rc = err_code; |
| 57 | |
| 58 | switch (err_code) { |
| 59 | case -ENOENT: |
| 60 | ecryptfs_printk(KERN_WARNING, "Missing auth tok\n"); |
| 61 | break; |
| 62 | case -EINVAL: |
| 63 | ecryptfs_printk(KERN_WARNING, "Invalid auth tok\n"); |
| 64 | break; |
| 65 | default: |
| 66 | rc = process_request_key_err(err_code); |
| 67 | break; |
| 68 | } |
| 69 | return rc; |
| 70 | } |
| 71 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 72 | /** |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 73 | * ecryptfs_parse_packet_length |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 74 | * @data: Pointer to memory containing length at offset |
| 75 | * @size: This function writes the decoded size to this memory |
| 76 | * address; zero on error |
| 77 | * @length_size: The number of bytes occupied by the encoded length |
| 78 | * |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 79 | * Returns zero on success; non-zero on error |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 80 | */ |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 81 | int ecryptfs_parse_packet_length(unsigned char *data, size_t *size, |
| 82 | size_t *length_size) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 83 | { |
| 84 | int rc = 0; |
| 85 | |
| 86 | (*length_size) = 0; |
| 87 | (*size) = 0; |
| 88 | if (data[0] < 192) { |
| 89 | /* One-byte length */ |
Tyler Hicks | 831115a | 2014-10-23 10:16:06 -0400 | [diff] [blame] | 90 | (*size) = data[0]; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 91 | (*length_size) = 1; |
| 92 | } else if (data[0] < 224) { |
| 93 | /* Two-byte length */ |
Tyler Hicks | 831115a | 2014-10-23 10:16:06 -0400 | [diff] [blame] | 94 | (*size) = (data[0] - 192) * 256; |
| 95 | (*size) += data[1] + 192; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 96 | (*length_size) = 2; |
| 97 | } else if (data[0] == 255) { |
Tyler Hicks | 48399c0 | 2012-01-14 16:46:46 +0100 | [diff] [blame] | 98 | /* If support is added, adjust ECRYPTFS_MAX_PKT_LEN_SIZE */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 99 | ecryptfs_printk(KERN_ERR, "Five-byte packet length not " |
| 100 | "supported\n"); |
| 101 | rc = -EINVAL; |
| 102 | goto out; |
| 103 | } else { |
| 104 | ecryptfs_printk(KERN_ERR, "Error parsing packet length\n"); |
| 105 | rc = -EINVAL; |
| 106 | goto out; |
| 107 | } |
| 108 | out: |
| 109 | return rc; |
| 110 | } |
| 111 | |
| 112 | /** |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 113 | * ecryptfs_write_packet_length |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 114 | * @dest: The byte array target into which to write the length. Must |
Tyler Hicks | 48399c0 | 2012-01-14 16:46:46 +0100 | [diff] [blame] | 115 | * have at least ECRYPTFS_MAX_PKT_LEN_SIZE bytes allocated. |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 116 | * @size: The length to write. |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 117 | * @packet_size_length: The number of bytes used to encode the packet |
| 118 | * length is written to this address. |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 119 | * |
| 120 | * Returns zero on success; non-zero on error. |
| 121 | */ |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 122 | int ecryptfs_write_packet_length(char *dest, size_t size, |
| 123 | size_t *packet_size_length) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 124 | { |
| 125 | int rc = 0; |
| 126 | |
| 127 | if (size < 192) { |
| 128 | dest[0] = size; |
| 129 | (*packet_size_length) = 1; |
| 130 | } else if (size < 65536) { |
| 131 | dest[0] = (((size - 192) / 256) + 192); |
| 132 | dest[1] = ((size - 192) % 256); |
| 133 | (*packet_size_length) = 2; |
| 134 | } else { |
Tyler Hicks | 48399c0 | 2012-01-14 16:46:46 +0100 | [diff] [blame] | 135 | /* If support is added, adjust ECRYPTFS_MAX_PKT_LEN_SIZE */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 136 | rc = -EINVAL; |
| 137 | ecryptfs_printk(KERN_WARNING, |
Tyler Hicks | f24b388 | 2010-11-15 17:36:38 -0600 | [diff] [blame] | 138 | "Unsupported packet size: [%zd]\n", size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 139 | } |
| 140 | return rc; |
| 141 | } |
| 142 | |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 143 | static int |
| 144 | write_tag_64_packet(char *signature, struct ecryptfs_session_key *session_key, |
| 145 | char **packet, size_t *packet_len) |
| 146 | { |
| 147 | size_t i = 0; |
| 148 | size_t data_len; |
| 149 | size_t packet_size_len; |
| 150 | char *message; |
| 151 | int rc; |
| 152 | |
| 153 | /* |
| 154 | * ***** TAG 64 Packet Format ***** |
| 155 | * | Content Type | 1 byte | |
| 156 | * | Key Identifier Size | 1 or 2 bytes | |
| 157 | * | Key Identifier | arbitrary | |
| 158 | * | Encrypted File Encryption Key Size | 1 or 2 bytes | |
| 159 | * | Encrypted File Encryption Key | arbitrary | |
| 160 | */ |
| 161 | data_len = (5 + ECRYPTFS_SIG_SIZE_HEX |
| 162 | + session_key->encrypted_key_size); |
| 163 | *packet = kmalloc(data_len, GFP_KERNEL); |
| 164 | message = *packet; |
| 165 | if (!message) { |
| 166 | ecryptfs_printk(KERN_ERR, "Unable to allocate memory\n"); |
| 167 | rc = -ENOMEM; |
| 168 | goto out; |
| 169 | } |
| 170 | message[i++] = ECRYPTFS_TAG_64_PACKET_TYPE; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 171 | rc = ecryptfs_write_packet_length(&message[i], ECRYPTFS_SIG_SIZE_HEX, |
| 172 | &packet_size_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 173 | if (rc) { |
| 174 | ecryptfs_printk(KERN_ERR, "Error generating tag 64 packet " |
| 175 | "header; cannot generate packet length\n"); |
| 176 | goto out; |
| 177 | } |
| 178 | i += packet_size_len; |
| 179 | memcpy(&message[i], signature, ECRYPTFS_SIG_SIZE_HEX); |
| 180 | i += ECRYPTFS_SIG_SIZE_HEX; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 181 | rc = ecryptfs_write_packet_length(&message[i], |
| 182 | session_key->encrypted_key_size, |
| 183 | &packet_size_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 184 | if (rc) { |
| 185 | ecryptfs_printk(KERN_ERR, "Error generating tag 64 packet " |
| 186 | "header; cannot generate packet length\n"); |
| 187 | goto out; |
| 188 | } |
| 189 | i += packet_size_len; |
| 190 | memcpy(&message[i], session_key->encrypted_key, |
| 191 | session_key->encrypted_key_size); |
| 192 | i += session_key->encrypted_key_size; |
| 193 | *packet_len = i; |
| 194 | out: |
| 195 | return rc; |
| 196 | } |
| 197 | |
| 198 | static int |
Trevor Highland | 19e66a6 | 2008-02-06 01:38:36 -0800 | [diff] [blame] | 199 | parse_tag_65_packet(struct ecryptfs_session_key *session_key, u8 *cipher_code, |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 200 | struct ecryptfs_message *msg) |
| 201 | { |
| 202 | size_t i = 0; |
| 203 | char *data; |
| 204 | size_t data_len; |
| 205 | size_t m_size; |
| 206 | size_t message_len; |
| 207 | u16 checksum = 0; |
| 208 | u16 expected_checksum = 0; |
| 209 | int rc; |
| 210 | |
| 211 | /* |
| 212 | * ***** TAG 65 Packet Format ***** |
| 213 | * | Content Type | 1 byte | |
| 214 | * | Status Indicator | 1 byte | |
| 215 | * | File Encryption Key Size | 1 or 2 bytes | |
| 216 | * | File Encryption Key | arbitrary | |
| 217 | */ |
| 218 | message_len = msg->data_len; |
| 219 | data = msg->data; |
| 220 | if (message_len < 4) { |
| 221 | rc = -EIO; |
| 222 | goto out; |
| 223 | } |
| 224 | if (data[i++] != ECRYPTFS_TAG_65_PACKET_TYPE) { |
| 225 | ecryptfs_printk(KERN_ERR, "Type should be ECRYPTFS_TAG_65\n"); |
| 226 | rc = -EIO; |
| 227 | goto out; |
| 228 | } |
| 229 | if (data[i++]) { |
| 230 | ecryptfs_printk(KERN_ERR, "Status indicator has non-zero value " |
| 231 | "[%d]\n", data[i-1]); |
| 232 | rc = -EIO; |
| 233 | goto out; |
| 234 | } |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 235 | rc = ecryptfs_parse_packet_length(&data[i], &m_size, &data_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 236 | if (rc) { |
| 237 | ecryptfs_printk(KERN_WARNING, "Error parsing packet length; " |
| 238 | "rc = [%d]\n", rc); |
| 239 | goto out; |
| 240 | } |
| 241 | i += data_len; |
| 242 | if (message_len < (i + m_size)) { |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 243 | ecryptfs_printk(KERN_ERR, "The message received from ecryptfsd " |
| 244 | "is shorter than expected\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 245 | rc = -EIO; |
| 246 | goto out; |
| 247 | } |
| 248 | if (m_size < 3) { |
| 249 | ecryptfs_printk(KERN_ERR, |
| 250 | "The decrypted key is not long enough to " |
| 251 | "include a cipher code and checksum\n"); |
| 252 | rc = -EIO; |
| 253 | goto out; |
| 254 | } |
| 255 | *cipher_code = data[i++]; |
| 256 | /* The decrypted key includes 1 byte cipher code and 2 byte checksum */ |
| 257 | session_key->decrypted_key_size = m_size - 3; |
| 258 | if (session_key->decrypted_key_size > ECRYPTFS_MAX_KEY_BYTES) { |
| 259 | ecryptfs_printk(KERN_ERR, "key_size [%d] larger than " |
| 260 | "the maximum key size [%d]\n", |
| 261 | session_key->decrypted_key_size, |
| 262 | ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES); |
| 263 | rc = -EIO; |
| 264 | goto out; |
| 265 | } |
| 266 | memcpy(session_key->decrypted_key, &data[i], |
| 267 | session_key->decrypted_key_size); |
| 268 | i += session_key->decrypted_key_size; |
| 269 | expected_checksum += (unsigned char)(data[i++]) << 8; |
| 270 | expected_checksum += (unsigned char)(data[i++]); |
| 271 | for (i = 0; i < session_key->decrypted_key_size; i++) |
| 272 | checksum += session_key->decrypted_key[i]; |
| 273 | if (expected_checksum != checksum) { |
| 274 | ecryptfs_printk(KERN_ERR, "Invalid checksum for file " |
| 275 | "encryption key; expected [%x]; calculated " |
| 276 | "[%x]\n", expected_checksum, checksum); |
| 277 | rc = -EIO; |
| 278 | } |
| 279 | out: |
| 280 | return rc; |
| 281 | } |
| 282 | |
| 283 | |
| 284 | static int |
Trevor Highland | 19e66a6 | 2008-02-06 01:38:36 -0800 | [diff] [blame] | 285 | write_tag_66_packet(char *signature, u8 cipher_code, |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 286 | struct ecryptfs_crypt_stat *crypt_stat, char **packet, |
| 287 | size_t *packet_len) |
| 288 | { |
| 289 | size_t i = 0; |
| 290 | size_t j; |
| 291 | size_t data_len; |
| 292 | size_t checksum = 0; |
| 293 | size_t packet_size_len; |
| 294 | char *message; |
| 295 | int rc; |
| 296 | |
| 297 | /* |
| 298 | * ***** TAG 66 Packet Format ***** |
| 299 | * | Content Type | 1 byte | |
| 300 | * | Key Identifier Size | 1 or 2 bytes | |
| 301 | * | Key Identifier | arbitrary | |
| 302 | * | File Encryption Key Size | 1 or 2 bytes | |
| 303 | * | File Encryption Key | arbitrary | |
| 304 | */ |
| 305 | data_len = (5 + ECRYPTFS_SIG_SIZE_HEX + crypt_stat->key_size); |
| 306 | *packet = kmalloc(data_len, GFP_KERNEL); |
| 307 | message = *packet; |
| 308 | if (!message) { |
| 309 | ecryptfs_printk(KERN_ERR, "Unable to allocate memory\n"); |
| 310 | rc = -ENOMEM; |
| 311 | goto out; |
| 312 | } |
| 313 | message[i++] = ECRYPTFS_TAG_66_PACKET_TYPE; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 314 | rc = ecryptfs_write_packet_length(&message[i], ECRYPTFS_SIG_SIZE_HEX, |
| 315 | &packet_size_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 316 | if (rc) { |
| 317 | ecryptfs_printk(KERN_ERR, "Error generating tag 66 packet " |
| 318 | "header; cannot generate packet length\n"); |
| 319 | goto out; |
| 320 | } |
| 321 | i += packet_size_len; |
| 322 | memcpy(&message[i], signature, ECRYPTFS_SIG_SIZE_HEX); |
| 323 | i += ECRYPTFS_SIG_SIZE_HEX; |
| 324 | /* The encrypted key includes 1 byte cipher code and 2 byte checksum */ |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 325 | rc = ecryptfs_write_packet_length(&message[i], crypt_stat->key_size + 3, |
| 326 | &packet_size_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 327 | if (rc) { |
| 328 | ecryptfs_printk(KERN_ERR, "Error generating tag 66 packet " |
| 329 | "header; cannot generate packet length\n"); |
| 330 | goto out; |
| 331 | } |
| 332 | i += packet_size_len; |
| 333 | message[i++] = cipher_code; |
| 334 | memcpy(&message[i], crypt_stat->key, crypt_stat->key_size); |
| 335 | i += crypt_stat->key_size; |
| 336 | for (j = 0; j < crypt_stat->key_size; j++) |
| 337 | checksum += crypt_stat->key[j]; |
| 338 | message[i++] = (checksum / 256) % 256; |
| 339 | message[i++] = (checksum % 256); |
| 340 | *packet_len = i; |
| 341 | out: |
| 342 | return rc; |
| 343 | } |
| 344 | |
| 345 | static int |
| 346 | parse_tag_67_packet(struct ecryptfs_key_record *key_rec, |
| 347 | struct ecryptfs_message *msg) |
| 348 | { |
| 349 | size_t i = 0; |
| 350 | char *data; |
| 351 | size_t data_len; |
| 352 | size_t message_len; |
| 353 | int rc; |
| 354 | |
| 355 | /* |
| 356 | * ***** TAG 65 Packet Format ***** |
| 357 | * | Content Type | 1 byte | |
| 358 | * | Status Indicator | 1 byte | |
| 359 | * | Encrypted File Encryption Key Size | 1 or 2 bytes | |
| 360 | * | Encrypted File Encryption Key | arbitrary | |
| 361 | */ |
| 362 | message_len = msg->data_len; |
| 363 | data = msg->data; |
| 364 | /* verify that everything through the encrypted FEK size is present */ |
| 365 | if (message_len < 4) { |
| 366 | rc = -EIO; |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 367 | printk(KERN_ERR "%s: message_len is [%zd]; minimum acceptable " |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 368 | "message length is [%d]\n", __func__, message_len, 4); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 369 | goto out; |
| 370 | } |
| 371 | if (data[i++] != ECRYPTFS_TAG_67_PACKET_TYPE) { |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 372 | rc = -EIO; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 373 | printk(KERN_ERR "%s: Type should be ECRYPTFS_TAG_67\n", |
| 374 | __func__); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 375 | goto out; |
| 376 | } |
| 377 | if (data[i++]) { |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 378 | rc = -EIO; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 379 | printk(KERN_ERR "%s: Status indicator has non zero " |
| 380 | "value [%d]\n", __func__, data[i-1]); |
| 381 | |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 382 | goto out; |
| 383 | } |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 384 | rc = ecryptfs_parse_packet_length(&data[i], &key_rec->enc_key_size, |
| 385 | &data_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 386 | if (rc) { |
| 387 | ecryptfs_printk(KERN_WARNING, "Error parsing packet length; " |
| 388 | "rc = [%d]\n", rc); |
| 389 | goto out; |
| 390 | } |
| 391 | i += data_len; |
| 392 | if (message_len < (i + key_rec->enc_key_size)) { |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 393 | rc = -EIO; |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 394 | printk(KERN_ERR "%s: message_len [%zd]; max len is [%zd]\n", |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 395 | __func__, message_len, (i + key_rec->enc_key_size)); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 396 | goto out; |
| 397 | } |
| 398 | if (key_rec->enc_key_size > ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES) { |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 399 | rc = -EIO; |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 400 | printk(KERN_ERR "%s: Encrypted key_size [%zd] larger than " |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 401 | "the maximum key size [%d]\n", __func__, |
| 402 | key_rec->enc_key_size, |
| 403 | ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 404 | goto out; |
| 405 | } |
| 406 | memcpy(key_rec->enc_key, &data[i], key_rec->enc_key_size); |
| 407 | out: |
| 408 | return rc; |
| 409 | } |
| 410 | |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 411 | /** |
| 412 | * ecryptfs_verify_version |
| 413 | * @version: The version number to confirm |
| 414 | * |
| 415 | * Returns zero on good version; non-zero otherwise |
| 416 | */ |
| 417 | static int ecryptfs_verify_version(u16 version) |
| 418 | { |
| 419 | int rc = 0; |
| 420 | unsigned char major; |
| 421 | unsigned char minor; |
| 422 | |
| 423 | major = ((version >> 8) & 0xFF); |
| 424 | minor = (version & 0xFF); |
| 425 | if (major != ECRYPTFS_VERSION_MAJOR) { |
| 426 | ecryptfs_printk(KERN_ERR, "Major version number mismatch. " |
| 427 | "Expected [%d]; got [%d]\n", |
| 428 | ECRYPTFS_VERSION_MAJOR, major); |
| 429 | rc = -EINVAL; |
| 430 | goto out; |
| 431 | } |
| 432 | if (minor != ECRYPTFS_VERSION_MINOR) { |
| 433 | ecryptfs_printk(KERN_ERR, "Minor version number mismatch. " |
| 434 | "Expected [%d]; got [%d]\n", |
| 435 | ECRYPTFS_VERSION_MINOR, minor); |
| 436 | rc = -EINVAL; |
| 437 | goto out; |
| 438 | } |
| 439 | out: |
| 440 | return rc; |
| 441 | } |
| 442 | |
| 443 | /** |
| 444 | * ecryptfs_verify_auth_tok_from_key |
| 445 | * @auth_tok_key: key containing the authentication token |
| 446 | * @auth_tok: authentication token |
| 447 | * |
Eric Biggers | f66665c | 2017-10-09 12:51:27 -0700 | [diff] [blame] | 448 | * Returns zero on valid auth tok; -EINVAL if the payload is invalid; or |
| 449 | * -EKEYREVOKED if the key was revoked before we acquired its semaphore. |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 450 | */ |
| 451 | static int |
| 452 | ecryptfs_verify_auth_tok_from_key(struct key *auth_tok_key, |
| 453 | struct ecryptfs_auth_tok **auth_tok) |
| 454 | { |
| 455 | int rc = 0; |
| 456 | |
| 457 | (*auth_tok) = ecryptfs_get_key_payload_data(auth_tok_key); |
Eric Biggers | f66665c | 2017-10-09 12:51:27 -0700 | [diff] [blame] | 458 | if (IS_ERR(*auth_tok)) { |
| 459 | rc = PTR_ERR(*auth_tok); |
| 460 | *auth_tok = NULL; |
| 461 | goto out; |
| 462 | } |
| 463 | |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 464 | if (ecryptfs_verify_version((*auth_tok)->version)) { |
| 465 | printk(KERN_ERR "Data structure version mismatch. Userspace " |
| 466 | "tools must match eCryptfs kernel module with major " |
| 467 | "version [%d] and minor version [%d]\n", |
| 468 | ECRYPTFS_VERSION_MAJOR, ECRYPTFS_VERSION_MINOR); |
| 469 | rc = -EINVAL; |
| 470 | goto out; |
| 471 | } |
| 472 | if ((*auth_tok)->token_type != ECRYPTFS_PASSWORD |
| 473 | && (*auth_tok)->token_type != ECRYPTFS_PRIVATE_KEY) { |
| 474 | printk(KERN_ERR "Invalid auth_tok structure " |
| 475 | "returned from key query\n"); |
| 476 | rc = -EINVAL; |
| 477 | goto out; |
| 478 | } |
| 479 | out: |
| 480 | return rc; |
| 481 | } |
| 482 | |
Michael Halcrow | cd9d67d | 2007-10-16 01:28:04 -0700 | [diff] [blame] | 483 | static int |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 484 | ecryptfs_find_global_auth_tok_for_sig( |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 485 | struct key **auth_tok_key, |
| 486 | struct ecryptfs_auth_tok **auth_tok, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 487 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat, char *sig) |
| 488 | { |
| 489 | struct ecryptfs_global_auth_tok *walker; |
| 490 | int rc = 0; |
| 491 | |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 492 | (*auth_tok_key) = NULL; |
| 493 | (*auth_tok) = NULL; |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 494 | mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex); |
| 495 | list_for_each_entry(walker, |
| 496 | &mount_crypt_stat->global_auth_tok_list, |
| 497 | mount_crypt_stat_list) { |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 498 | if (memcmp(walker->sig, sig, ECRYPTFS_SIG_SIZE_HEX)) |
| 499 | continue; |
| 500 | |
| 501 | if (walker->flags & ECRYPTFS_AUTH_TOK_INVALID) { |
| 502 | rc = -EINVAL; |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 503 | goto out; |
| 504 | } |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 505 | |
| 506 | rc = key_validate(walker->global_auth_tok_key); |
| 507 | if (rc) { |
| 508 | if (rc == -EKEYEXPIRED) |
| 509 | goto out; |
| 510 | goto out_invalid_auth_tok; |
| 511 | } |
| 512 | |
Roberto Sassu | b5695d0 | 2011-03-21 16:00:55 +0100 | [diff] [blame] | 513 | down_write(&(walker->global_auth_tok_key->sem)); |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 514 | rc = ecryptfs_verify_auth_tok_from_key( |
| 515 | walker->global_auth_tok_key, auth_tok); |
| 516 | if (rc) |
Roberto Sassu | b5695d0 | 2011-03-21 16:00:55 +0100 | [diff] [blame] | 517 | goto out_invalid_auth_tok_unlock; |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 518 | |
| 519 | (*auth_tok_key) = walker->global_auth_tok_key; |
| 520 | key_get(*auth_tok_key); |
| 521 | goto out; |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 522 | } |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 523 | rc = -ENOENT; |
| 524 | goto out; |
Roberto Sassu | b5695d0 | 2011-03-21 16:00:55 +0100 | [diff] [blame] | 525 | out_invalid_auth_tok_unlock: |
| 526 | up_write(&(walker->global_auth_tok_key->sem)); |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 527 | out_invalid_auth_tok: |
| 528 | printk(KERN_WARNING "Invalidating auth tok with sig = [%s]\n", sig); |
| 529 | walker->flags |= ECRYPTFS_AUTH_TOK_INVALID; |
| 530 | key_put(walker->global_auth_tok_key); |
| 531 | walker->global_auth_tok_key = NULL; |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 532 | out: |
| 533 | mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex); |
| 534 | return rc; |
| 535 | } |
| 536 | |
| 537 | /** |
| 538 | * ecryptfs_find_auth_tok_for_sig |
Lee Jones | ffbed07 | 2021-03-30 17:44:58 +0100 | [diff] [blame] | 539 | * @auth_tok_key: key containing the authentication token |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 540 | * @auth_tok: Set to the matching auth_tok; NULL if not found |
Lee Jones | ffbed07 | 2021-03-30 17:44:58 +0100 | [diff] [blame] | 541 | * @mount_crypt_stat: inode crypt_stat crypto context |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 542 | * @sig: Sig of auth_tok to find |
| 543 | * |
| 544 | * For now, this function simply looks at the registered auth_tok's |
| 545 | * linked off the mount_crypt_stat, so all the auth_toks that can be |
| 546 | * used must be registered at mount time. This function could |
| 547 | * potentially try a lot harder to find auth_tok's (e.g., by calling |
| 548 | * out to ecryptfsd to dynamically retrieve an auth_tok object) so |
| 549 | * that static registration of auth_tok's will no longer be necessary. |
| 550 | * |
| 551 | * Returns zero on no error; non-zero on error |
| 552 | */ |
| 553 | static int |
| 554 | ecryptfs_find_auth_tok_for_sig( |
Roberto Sassu | aee683b | 2010-10-06 18:31:06 +0200 | [diff] [blame] | 555 | struct key **auth_tok_key, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 556 | struct ecryptfs_auth_tok **auth_tok, |
| 557 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat, |
| 558 | char *sig) |
| 559 | { |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 560 | int rc = 0; |
| 561 | |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 562 | rc = ecryptfs_find_global_auth_tok_for_sig(auth_tok_key, auth_tok, |
| 563 | mount_crypt_stat, sig); |
| 564 | if (rc == -ENOENT) { |
Roberto Sassu | f16feb5 | 2010-10-06 18:31:32 +0200 | [diff] [blame] | 565 | /* if the flag ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY is set in the |
| 566 | * mount_crypt_stat structure, we prevent to use auth toks that |
| 567 | * are not inserted through the ecryptfs_add_global_auth_tok |
| 568 | * function. |
| 569 | */ |
| 570 | if (mount_crypt_stat->flags |
| 571 | & ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY) |
| 572 | return -EINVAL; |
| 573 | |
Roberto Sassu | aee683b | 2010-10-06 18:31:06 +0200 | [diff] [blame] | 574 | rc = ecryptfs_keyring_auth_tok_for_sig(auth_tok_key, auth_tok, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 575 | sig); |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 576 | } |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 577 | return rc; |
| 578 | } |
| 579 | |
Lee Jones | ffbed07 | 2021-03-30 17:44:58 +0100 | [diff] [blame] | 580 | /* |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 581 | * write_tag_70_packet can gobble a lot of stack space. We stuff most |
| 582 | * of the function's parameters in a kmalloc'd struct to help reduce |
| 583 | * eCryptfs' overall stack usage. |
| 584 | */ |
| 585 | struct ecryptfs_write_tag_70_packet_silly_stack { |
| 586 | u8 cipher_code; |
| 587 | size_t max_packet_size; |
| 588 | size_t packet_size_len; |
| 589 | size_t block_aligned_filename_size; |
| 590 | size_t block_size; |
| 591 | size_t i; |
| 592 | size_t j; |
| 593 | size_t num_rand_bytes; |
| 594 | struct mutex *tfm_mutex; |
| 595 | char *block_aligned_filename; |
| 596 | struct ecryptfs_auth_tok *auth_tok; |
Tyler Hicks | 8d08dab | 2011-05-17 00:50:33 -0500 | [diff] [blame] | 597 | struct scatterlist src_sg[2]; |
| 598 | struct scatterlist dst_sg[2]; |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 599 | struct crypto_skcipher *skcipher_tfm; |
| 600 | struct skcipher_request *skcipher_req; |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 601 | char iv[ECRYPTFS_MAX_IV_BYTES]; |
| 602 | char hash[ECRYPTFS_TAG_70_DIGEST_SIZE]; |
| 603 | char tmp_hash[ECRYPTFS_TAG_70_DIGEST_SIZE]; |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 604 | struct crypto_shash *hash_tfm; |
| 605 | struct shash_desc *hash_desc; |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 606 | }; |
| 607 | |
Lee Jones | ffbed07 | 2021-03-30 17:44:58 +0100 | [diff] [blame] | 608 | /* |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 609 | * write_tag_70_packet - Write encrypted filename (EFN) packet against FNEK |
| 610 | * @filename: NULL-terminated filename string |
| 611 | * |
| 612 | * This is the simplest mechanism for achieving filename encryption in |
| 613 | * eCryptfs. It encrypts the given filename with the mount-wide |
| 614 | * filename encryption key (FNEK) and stores it in a packet to @dest, |
| 615 | * which the callee will encode and write directly into the dentry |
| 616 | * name. |
| 617 | */ |
| 618 | int |
| 619 | ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes, |
| 620 | size_t *packet_size, |
| 621 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat, |
| 622 | char *filename, size_t filename_size) |
| 623 | { |
| 624 | struct ecryptfs_write_tag_70_packet_silly_stack *s; |
Roberto Sassu | aee683b | 2010-10-06 18:31:06 +0200 | [diff] [blame] | 625 | struct key *auth_tok_key = NULL; |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 626 | int rc = 0; |
| 627 | |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 628 | s = kzalloc(sizeof(*s), GFP_KERNEL); |
Markus Elfring | 1a0bba4 | 2017-08-19 17:37:30 +0200 | [diff] [blame] | 629 | if (!s) |
Herbert Xu | d1558f4 | 2016-03-16 17:06:01 +0800 | [diff] [blame] | 630 | return -ENOMEM; |
Markus Elfring | 1a0bba4 | 2017-08-19 17:37:30 +0200 | [diff] [blame] | 631 | |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 632 | (*packet_size) = 0; |
Roberto Sassu | 950983f | 2011-03-21 16:00:54 +0100 | [diff] [blame] | 633 | rc = ecryptfs_find_auth_tok_for_sig( |
| 634 | &auth_tok_key, |
| 635 | &s->auth_tok, mount_crypt_stat, |
| 636 | mount_crypt_stat->global_default_fnek_sig); |
| 637 | if (rc) { |
| 638 | printk(KERN_ERR "%s: Error attempting to find auth tok for " |
| 639 | "fnek sig [%s]; rc = [%d]\n", __func__, |
| 640 | mount_crypt_stat->global_default_fnek_sig, rc); |
| 641 | goto out; |
| 642 | } |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 643 | rc = ecryptfs_get_tfm_and_mutex_for_cipher_name( |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 644 | &s->skcipher_tfm, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 645 | &s->tfm_mutex, mount_crypt_stat->global_default_fn_cipher_name); |
| 646 | if (unlikely(rc)) { |
| 647 | printk(KERN_ERR "Internal error whilst attempting to get " |
| 648 | "tfm and mutex for cipher name [%s]; rc = [%d]\n", |
| 649 | mount_crypt_stat->global_default_fn_cipher_name, rc); |
| 650 | goto out; |
| 651 | } |
| 652 | mutex_lock(s->tfm_mutex); |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 653 | s->block_size = crypto_skcipher_blocksize(s->skcipher_tfm); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 654 | /* Plus one for the \0 separator between the random prefix |
| 655 | * and the plaintext filename */ |
| 656 | s->num_rand_bytes = (ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES + 1); |
| 657 | s->block_aligned_filename_size = (s->num_rand_bytes + filename_size); |
| 658 | if ((s->block_aligned_filename_size % s->block_size) != 0) { |
| 659 | s->num_rand_bytes += (s->block_size |
| 660 | - (s->block_aligned_filename_size |
| 661 | % s->block_size)); |
| 662 | s->block_aligned_filename_size = (s->num_rand_bytes |
| 663 | + filename_size); |
| 664 | } |
| 665 | /* Octet 0: Tag 70 identifier |
| 666 | * Octets 1-N1: Tag 70 packet size (includes cipher identifier |
| 667 | * and block-aligned encrypted filename size) |
| 668 | * Octets N1-N2: FNEK sig (ECRYPTFS_SIG_SIZE) |
| 669 | * Octet N2-N3: Cipher identifier (1 octet) |
| 670 | * Octets N3-N4: Block-aligned encrypted filename |
| 671 | * - Consists of a minimum number of random characters, a \0 |
| 672 | * separator, and then the filename */ |
Tyler Hicks | 4a26620 | 2011-11-05 13:45:08 -0400 | [diff] [blame] | 673 | s->max_packet_size = (ECRYPTFS_TAG_70_MAX_METADATA_SIZE |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 674 | + s->block_aligned_filename_size); |
Markus Elfring | 5032f36 | 2017-08-19 18:00:22 +0200 | [diff] [blame] | 675 | if (!dest) { |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 676 | (*packet_size) = s->max_packet_size; |
| 677 | goto out_unlock; |
| 678 | } |
| 679 | if (s->max_packet_size > (*remaining_bytes)) { |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 680 | printk(KERN_WARNING "%s: Require [%zd] bytes to write; only " |
| 681 | "[%zd] available\n", __func__, s->max_packet_size, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 682 | (*remaining_bytes)); |
| 683 | rc = -EINVAL; |
| 684 | goto out_unlock; |
| 685 | } |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 686 | |
| 687 | s->skcipher_req = skcipher_request_alloc(s->skcipher_tfm, GFP_KERNEL); |
| 688 | if (!s->skcipher_req) { |
| 689 | printk(KERN_ERR "%s: Out of kernel memory whilst attempting to " |
| 690 | "skcipher_request_alloc for %s\n", __func__, |
| 691 | crypto_skcipher_driver_name(s->skcipher_tfm)); |
| 692 | rc = -ENOMEM; |
| 693 | goto out_unlock; |
| 694 | } |
| 695 | |
| 696 | skcipher_request_set_callback(s->skcipher_req, |
| 697 | CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL); |
| 698 | |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 699 | s->block_aligned_filename = kzalloc(s->block_aligned_filename_size, |
| 700 | GFP_KERNEL); |
| 701 | if (!s->block_aligned_filename) { |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 702 | rc = -ENOMEM; |
| 703 | goto out_unlock; |
| 704 | } |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 705 | dest[s->i++] = ECRYPTFS_TAG_70_PACKET_TYPE; |
| 706 | rc = ecryptfs_write_packet_length(&dest[s->i], |
| 707 | (ECRYPTFS_SIG_SIZE |
| 708 | + 1 /* Cipher code */ |
| 709 | + s->block_aligned_filename_size), |
| 710 | &s->packet_size_len); |
| 711 | if (rc) { |
| 712 | printk(KERN_ERR "%s: Error generating tag 70 packet " |
| 713 | "header; cannot generate packet length; rc = [%d]\n", |
| 714 | __func__, rc); |
| 715 | goto out_free_unlock; |
| 716 | } |
| 717 | s->i += s->packet_size_len; |
| 718 | ecryptfs_from_hex(&dest[s->i], |
| 719 | mount_crypt_stat->global_default_fnek_sig, |
| 720 | ECRYPTFS_SIG_SIZE); |
| 721 | s->i += ECRYPTFS_SIG_SIZE; |
| 722 | s->cipher_code = ecryptfs_code_for_cipher_string( |
| 723 | mount_crypt_stat->global_default_fn_cipher_name, |
| 724 | mount_crypt_stat->global_default_fn_cipher_key_bytes); |
| 725 | if (s->cipher_code == 0) { |
| 726 | printk(KERN_WARNING "%s: Unable to generate code for " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 727 | "cipher [%s] with key bytes [%zd]\n", __func__, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 728 | mount_crypt_stat->global_default_fn_cipher_name, |
| 729 | mount_crypt_stat->global_default_fn_cipher_key_bytes); |
| 730 | rc = -EINVAL; |
| 731 | goto out_free_unlock; |
| 732 | } |
| 733 | dest[s->i++] = s->cipher_code; |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 734 | /* TODO: Support other key modules than passphrase for |
| 735 | * filename encryption */ |
Tyler Hicks | df6ad33 | 2009-08-21 04:27:46 -0500 | [diff] [blame] | 736 | if (s->auth_tok->token_type != ECRYPTFS_PASSWORD) { |
| 737 | rc = -EOPNOTSUPP; |
| 738 | printk(KERN_INFO "%s: Filename encryption only supports " |
| 739 | "password tokens\n", __func__); |
| 740 | goto out_free_unlock; |
| 741 | } |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 742 | s->hash_tfm = crypto_alloc_shash(ECRYPTFS_TAG_70_DIGEST, 0, 0); |
| 743 | if (IS_ERR(s->hash_tfm)) { |
| 744 | rc = PTR_ERR(s->hash_tfm); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 745 | printk(KERN_ERR "%s: Error attempting to " |
| 746 | "allocate hash crypto context; rc = [%d]\n", |
| 747 | __func__, rc); |
| 748 | goto out_free_unlock; |
| 749 | } |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 750 | |
| 751 | s->hash_desc = kmalloc(sizeof(*s->hash_desc) + |
| 752 | crypto_shash_descsize(s->hash_tfm), GFP_KERNEL); |
| 753 | if (!s->hash_desc) { |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 754 | rc = -ENOMEM; |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 755 | goto out_release_free_unlock; |
| 756 | } |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 757 | |
| 758 | s->hash_desc->tfm = s->hash_tfm; |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 759 | |
| 760 | rc = crypto_shash_digest(s->hash_desc, |
| 761 | (u8 *)s->auth_tok->token.password.session_key_encryption_key, |
| 762 | s->auth_tok->token.password.session_key_encryption_key_bytes, |
| 763 | s->hash); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 764 | if (rc) { |
| 765 | printk(KERN_ERR |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 766 | "%s: Error computing crypto hash; rc = [%d]\n", |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 767 | __func__, rc); |
| 768 | goto out_release_free_unlock; |
| 769 | } |
| 770 | for (s->j = 0; s->j < (s->num_rand_bytes - 1); s->j++) { |
| 771 | s->block_aligned_filename[s->j] = |
| 772 | s->hash[(s->j % ECRYPTFS_TAG_70_DIGEST_SIZE)]; |
| 773 | if ((s->j % ECRYPTFS_TAG_70_DIGEST_SIZE) |
| 774 | == (ECRYPTFS_TAG_70_DIGEST_SIZE - 1)) { |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 775 | rc = crypto_shash_digest(s->hash_desc, (u8 *)s->hash, |
| 776 | ECRYPTFS_TAG_70_DIGEST_SIZE, |
| 777 | s->tmp_hash); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 778 | if (rc) { |
| 779 | printk(KERN_ERR |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 780 | "%s: Error computing crypto hash; " |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 781 | "rc = [%d]\n", __func__, rc); |
| 782 | goto out_release_free_unlock; |
| 783 | } |
| 784 | memcpy(s->hash, s->tmp_hash, |
| 785 | ECRYPTFS_TAG_70_DIGEST_SIZE); |
| 786 | } |
| 787 | if (s->block_aligned_filename[s->j] == '\0') |
| 788 | s->block_aligned_filename[s->j] = ECRYPTFS_NON_NULL; |
| 789 | } |
| 790 | memcpy(&s->block_aligned_filename[s->num_rand_bytes], filename, |
| 791 | filename_size); |
| 792 | rc = virt_to_scatterlist(s->block_aligned_filename, |
Tyler Hicks | 8d08dab | 2011-05-17 00:50:33 -0500 | [diff] [blame] | 793 | s->block_aligned_filename_size, s->src_sg, 2); |
| 794 | if (rc < 1) { |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 795 | printk(KERN_ERR "%s: Internal error whilst attempting to " |
Tyler Hicks | 8d08dab | 2011-05-17 00:50:33 -0500 | [diff] [blame] | 796 | "convert filename memory to scatterlist; rc = [%d]. " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 797 | "block_aligned_filename_size = [%zd]\n", __func__, rc, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 798 | s->block_aligned_filename_size); |
| 799 | goto out_release_free_unlock; |
| 800 | } |
| 801 | rc = virt_to_scatterlist(&dest[s->i], s->block_aligned_filename_size, |
Tyler Hicks | 8d08dab | 2011-05-17 00:50:33 -0500 | [diff] [blame] | 802 | s->dst_sg, 2); |
| 803 | if (rc < 1) { |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 804 | printk(KERN_ERR "%s: Internal error whilst attempting to " |
| 805 | "convert encrypted filename memory to scatterlist; " |
Tyler Hicks | 8d08dab | 2011-05-17 00:50:33 -0500 | [diff] [blame] | 806 | "rc = [%d]. block_aligned_filename_size = [%zd]\n", |
| 807 | __func__, rc, s->block_aligned_filename_size); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 808 | goto out_release_free_unlock; |
| 809 | } |
| 810 | /* The characters in the first block effectively do the job |
| 811 | * of the IV here, so we just use 0's for the IV. Note the |
| 812 | * constraint that ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES |
| 813 | * >= ECRYPTFS_MAX_IV_BYTES. */ |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 814 | rc = crypto_skcipher_setkey( |
| 815 | s->skcipher_tfm, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 816 | s->auth_tok->token.password.session_key_encryption_key, |
| 817 | mount_crypt_stat->global_default_fn_cipher_key_bytes); |
| 818 | if (rc < 0) { |
| 819 | printk(KERN_ERR "%s: Error setting key for crypto context; " |
| 820 | "rc = [%d]. s->auth_tok->token.password.session_key_" |
| 821 | "encryption_key = [0x%p]; mount_crypt_stat->" |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 822 | "global_default_fn_cipher_key_bytes = [%zd]\n", __func__, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 823 | rc, |
| 824 | s->auth_tok->token.password.session_key_encryption_key, |
| 825 | mount_crypt_stat->global_default_fn_cipher_key_bytes); |
| 826 | goto out_release_free_unlock; |
| 827 | } |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 828 | skcipher_request_set_crypt(s->skcipher_req, s->src_sg, s->dst_sg, |
| 829 | s->block_aligned_filename_size, s->iv); |
| 830 | rc = crypto_skcipher_encrypt(s->skcipher_req); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 831 | if (rc) { |
| 832 | printk(KERN_ERR "%s: Error attempting to encrypt filename; " |
| 833 | "rc = [%d]\n", __func__, rc); |
| 834 | goto out_release_free_unlock; |
| 835 | } |
| 836 | s->i += s->block_aligned_filename_size; |
| 837 | (*packet_size) = s->i; |
| 838 | (*remaining_bytes) -= (*packet_size); |
| 839 | out_release_free_unlock: |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 840 | crypto_free_shash(s->hash_tfm); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 841 | out_free_unlock: |
Waiman Long | 453431a | 2020-08-06 23:18:13 -0700 | [diff] [blame] | 842 | kfree_sensitive(s->block_aligned_filename); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 843 | out_unlock: |
| 844 | mutex_unlock(s->tfm_mutex); |
| 845 | out: |
Roberto Sassu | b5695d0 | 2011-03-21 16:00:55 +0100 | [diff] [blame] | 846 | if (auth_tok_key) { |
| 847 | up_write(&(auth_tok_key->sem)); |
Roberto Sassu | aee683b | 2010-10-06 18:31:06 +0200 | [diff] [blame] | 848 | key_put(auth_tok_key); |
Roberto Sassu | b5695d0 | 2011-03-21 16:00:55 +0100 | [diff] [blame] | 849 | } |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 850 | skcipher_request_free(s->skcipher_req); |
Waiman Long | 453431a | 2020-08-06 23:18:13 -0700 | [diff] [blame] | 851 | kfree_sensitive(s->hash_desc); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 852 | kfree(s); |
| 853 | return rc; |
| 854 | } |
| 855 | |
| 856 | struct ecryptfs_parse_tag_70_packet_silly_stack { |
| 857 | u8 cipher_code; |
| 858 | size_t max_packet_size; |
| 859 | size_t packet_size_len; |
| 860 | size_t parsed_tag_70_packet_size; |
| 861 | size_t block_aligned_filename_size; |
| 862 | size_t block_size; |
| 863 | size_t i; |
| 864 | struct mutex *tfm_mutex; |
| 865 | char *decrypted_filename; |
| 866 | struct ecryptfs_auth_tok *auth_tok; |
Tyler Hicks | 8d08dab | 2011-05-17 00:50:33 -0500 | [diff] [blame] | 867 | struct scatterlist src_sg[2]; |
| 868 | struct scatterlist dst_sg[2]; |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 869 | struct crypto_skcipher *skcipher_tfm; |
| 870 | struct skcipher_request *skcipher_req; |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 871 | char fnek_sig_hex[ECRYPTFS_SIG_SIZE_HEX + 1]; |
| 872 | char iv[ECRYPTFS_MAX_IV_BYTES]; |
Colin Ian King | 2a559a8 | 2015-02-23 11:34:10 +0000 | [diff] [blame] | 873 | char cipher_string[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1]; |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 874 | }; |
| 875 | |
| 876 | /** |
Lee Jones | ffbed07 | 2021-03-30 17:44:58 +0100 | [diff] [blame] | 877 | * ecryptfs_parse_tag_70_packet - Parse and process FNEK-encrypted passphrase packet |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 878 | * @filename: This function kmalloc's the memory for the filename |
Michael Halcrow | 7d8bc2b | 2009-01-06 14:42:04 -0800 | [diff] [blame] | 879 | * @filename_size: This function sets this to the amount of memory |
| 880 | * kmalloc'd for the filename |
| 881 | * @packet_size: This function sets this to the the number of octets |
| 882 | * in the packet parsed |
| 883 | * @mount_crypt_stat: The mount-wide cryptographic context |
| 884 | * @data: The memory location containing the start of the tag 70 |
| 885 | * packet |
| 886 | * @max_packet_size: The maximum legal size of the packet to be parsed |
| 887 | * from @data |
| 888 | * |
| 889 | * Returns zero on success; non-zero otherwise |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 890 | */ |
| 891 | int |
| 892 | ecryptfs_parse_tag_70_packet(char **filename, size_t *filename_size, |
| 893 | size_t *packet_size, |
| 894 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat, |
| 895 | char *data, size_t max_packet_size) |
| 896 | { |
| 897 | struct ecryptfs_parse_tag_70_packet_silly_stack *s; |
Roberto Sassu | aee683b | 2010-10-06 18:31:06 +0200 | [diff] [blame] | 898 | struct key *auth_tok_key = NULL; |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 899 | int rc = 0; |
| 900 | |
| 901 | (*packet_size) = 0; |
| 902 | (*filename_size) = 0; |
| 903 | (*filename) = NULL; |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 904 | s = kzalloc(sizeof(*s), GFP_KERNEL); |
Markus Elfring | 1a0bba4 | 2017-08-19 17:37:30 +0200 | [diff] [blame] | 905 | if (!s) |
Herbert Xu | d1558f4 | 2016-03-16 17:06:01 +0800 | [diff] [blame] | 906 | return -ENOMEM; |
Markus Elfring | 1a0bba4 | 2017-08-19 17:37:30 +0200 | [diff] [blame] | 907 | |
Tyler Hicks | 4a26620 | 2011-11-05 13:45:08 -0400 | [diff] [blame] | 908 | if (max_packet_size < ECRYPTFS_TAG_70_MIN_METADATA_SIZE) { |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 909 | printk(KERN_WARNING "%s: max_packet_size is [%zd]; it must be " |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 910 | "at least [%d]\n", __func__, max_packet_size, |
Tyler Hicks | 4a26620 | 2011-11-05 13:45:08 -0400 | [diff] [blame] | 911 | ECRYPTFS_TAG_70_MIN_METADATA_SIZE); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 912 | rc = -EINVAL; |
| 913 | goto out; |
| 914 | } |
| 915 | /* Octet 0: Tag 70 identifier |
| 916 | * Octets 1-N1: Tag 70 packet size (includes cipher identifier |
| 917 | * and block-aligned encrypted filename size) |
| 918 | * Octets N1-N2: FNEK sig (ECRYPTFS_SIG_SIZE) |
| 919 | * Octet N2-N3: Cipher identifier (1 octet) |
| 920 | * Octets N3-N4: Block-aligned encrypted filename |
| 921 | * - Consists of a minimum number of random numbers, a \0 |
| 922 | * separator, and then the filename */ |
| 923 | if (data[(*packet_size)++] != ECRYPTFS_TAG_70_PACKET_TYPE) { |
| 924 | printk(KERN_WARNING "%s: Invalid packet tag [0x%.2x]; must be " |
| 925 | "tag [0x%.2x]\n", __func__, |
| 926 | data[((*packet_size) - 1)], ECRYPTFS_TAG_70_PACKET_TYPE); |
| 927 | rc = -EINVAL; |
| 928 | goto out; |
| 929 | } |
| 930 | rc = ecryptfs_parse_packet_length(&data[(*packet_size)], |
| 931 | &s->parsed_tag_70_packet_size, |
| 932 | &s->packet_size_len); |
| 933 | if (rc) { |
| 934 | printk(KERN_WARNING "%s: Error parsing packet length; " |
| 935 | "rc = [%d]\n", __func__, rc); |
| 936 | goto out; |
| 937 | } |
| 938 | s->block_aligned_filename_size = (s->parsed_tag_70_packet_size |
| 939 | - ECRYPTFS_SIG_SIZE - 1); |
| 940 | if ((1 + s->packet_size_len + s->parsed_tag_70_packet_size) |
| 941 | > max_packet_size) { |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 942 | printk(KERN_WARNING "%s: max_packet_size is [%zd]; real packet " |
| 943 | "size is [%zd]\n", __func__, max_packet_size, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 944 | (1 + s->packet_size_len + 1 |
| 945 | + s->block_aligned_filename_size)); |
| 946 | rc = -EINVAL; |
| 947 | goto out; |
| 948 | } |
| 949 | (*packet_size) += s->packet_size_len; |
| 950 | ecryptfs_to_hex(s->fnek_sig_hex, &data[(*packet_size)], |
| 951 | ECRYPTFS_SIG_SIZE); |
| 952 | s->fnek_sig_hex[ECRYPTFS_SIG_SIZE_HEX] = '\0'; |
| 953 | (*packet_size) += ECRYPTFS_SIG_SIZE; |
| 954 | s->cipher_code = data[(*packet_size)++]; |
| 955 | rc = ecryptfs_cipher_code_to_string(s->cipher_string, s->cipher_code); |
| 956 | if (rc) { |
| 957 | printk(KERN_WARNING "%s: Cipher code [%d] is invalid\n", |
| 958 | __func__, s->cipher_code); |
| 959 | goto out; |
| 960 | } |
Roberto Sassu | 950983f | 2011-03-21 16:00:54 +0100 | [diff] [blame] | 961 | rc = ecryptfs_find_auth_tok_for_sig(&auth_tok_key, |
| 962 | &s->auth_tok, mount_crypt_stat, |
| 963 | s->fnek_sig_hex); |
| 964 | if (rc) { |
| 965 | printk(KERN_ERR "%s: Error attempting to find auth tok for " |
| 966 | "fnek sig [%s]; rc = [%d]\n", __func__, s->fnek_sig_hex, |
| 967 | rc); |
| 968 | goto out; |
| 969 | } |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 970 | rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(&s->skcipher_tfm, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 971 | &s->tfm_mutex, |
| 972 | s->cipher_string); |
| 973 | if (unlikely(rc)) { |
| 974 | printk(KERN_ERR "Internal error whilst attempting to get " |
| 975 | "tfm and mutex for cipher name [%s]; rc = [%d]\n", |
| 976 | s->cipher_string, rc); |
| 977 | goto out; |
| 978 | } |
| 979 | mutex_lock(s->tfm_mutex); |
| 980 | rc = virt_to_scatterlist(&data[(*packet_size)], |
Tyler Hicks | 8d08dab | 2011-05-17 00:50:33 -0500 | [diff] [blame] | 981 | s->block_aligned_filename_size, s->src_sg, 2); |
| 982 | if (rc < 1) { |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 983 | printk(KERN_ERR "%s: Internal error whilst attempting to " |
| 984 | "convert encrypted filename memory to scatterlist; " |
Tyler Hicks | 8d08dab | 2011-05-17 00:50:33 -0500 | [diff] [blame] | 985 | "rc = [%d]. block_aligned_filename_size = [%zd]\n", |
| 986 | __func__, rc, s->block_aligned_filename_size); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 987 | goto out_unlock; |
| 988 | } |
| 989 | (*packet_size) += s->block_aligned_filename_size; |
| 990 | s->decrypted_filename = kmalloc(s->block_aligned_filename_size, |
| 991 | GFP_KERNEL); |
| 992 | if (!s->decrypted_filename) { |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 993 | rc = -ENOMEM; |
| 994 | goto out_unlock; |
| 995 | } |
| 996 | rc = virt_to_scatterlist(s->decrypted_filename, |
Tyler Hicks | 8d08dab | 2011-05-17 00:50:33 -0500 | [diff] [blame] | 997 | s->block_aligned_filename_size, s->dst_sg, 2); |
| 998 | if (rc < 1) { |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 999 | printk(KERN_ERR "%s: Internal error whilst attempting to " |
| 1000 | "convert decrypted filename memory to scatterlist; " |
Tyler Hicks | 8d08dab | 2011-05-17 00:50:33 -0500 | [diff] [blame] | 1001 | "rc = [%d]. block_aligned_filename_size = [%zd]\n", |
| 1002 | __func__, rc, s->block_aligned_filename_size); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1003 | goto out_free_unlock; |
| 1004 | } |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1005 | |
| 1006 | s->skcipher_req = skcipher_request_alloc(s->skcipher_tfm, GFP_KERNEL); |
| 1007 | if (!s->skcipher_req) { |
| 1008 | printk(KERN_ERR "%s: Out of kernel memory whilst attempting to " |
| 1009 | "skcipher_request_alloc for %s\n", __func__, |
| 1010 | crypto_skcipher_driver_name(s->skcipher_tfm)); |
| 1011 | rc = -ENOMEM; |
| 1012 | goto out_free_unlock; |
| 1013 | } |
| 1014 | |
| 1015 | skcipher_request_set_callback(s->skcipher_req, |
| 1016 | CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL); |
| 1017 | |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1018 | /* The characters in the first block effectively do the job of |
| 1019 | * the IV here, so we just use 0's for the IV. Note the |
| 1020 | * constraint that ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES |
| 1021 | * >= ECRYPTFS_MAX_IV_BYTES. */ |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1022 | /* TODO: Support other key modules than passphrase for |
| 1023 | * filename encryption */ |
Tyler Hicks | df6ad33 | 2009-08-21 04:27:46 -0500 | [diff] [blame] | 1024 | if (s->auth_tok->token_type != ECRYPTFS_PASSWORD) { |
| 1025 | rc = -EOPNOTSUPP; |
| 1026 | printk(KERN_INFO "%s: Filename encryption only supports " |
| 1027 | "password tokens\n", __func__); |
| 1028 | goto out_free_unlock; |
| 1029 | } |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1030 | rc = crypto_skcipher_setkey( |
| 1031 | s->skcipher_tfm, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1032 | s->auth_tok->token.password.session_key_encryption_key, |
| 1033 | mount_crypt_stat->global_default_fn_cipher_key_bytes); |
| 1034 | if (rc < 0) { |
| 1035 | printk(KERN_ERR "%s: Error setting key for crypto context; " |
| 1036 | "rc = [%d]. s->auth_tok->token.password.session_key_" |
| 1037 | "encryption_key = [0x%p]; mount_crypt_stat->" |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 1038 | "global_default_fn_cipher_key_bytes = [%zd]\n", __func__, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1039 | rc, |
| 1040 | s->auth_tok->token.password.session_key_encryption_key, |
| 1041 | mount_crypt_stat->global_default_fn_cipher_key_bytes); |
| 1042 | goto out_free_unlock; |
| 1043 | } |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1044 | skcipher_request_set_crypt(s->skcipher_req, s->src_sg, s->dst_sg, |
| 1045 | s->block_aligned_filename_size, s->iv); |
| 1046 | rc = crypto_skcipher_decrypt(s->skcipher_req); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1047 | if (rc) { |
| 1048 | printk(KERN_ERR "%s: Error attempting to decrypt filename; " |
| 1049 | "rc = [%d]\n", __func__, rc); |
| 1050 | goto out_free_unlock; |
| 1051 | } |
Dan Carpenter | 4b47a8b | 2018-08-22 13:43:59 +0300 | [diff] [blame] | 1052 | |
| 1053 | while (s->i < s->block_aligned_filename_size && |
| 1054 | s->decrypted_filename[s->i] != '\0') |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1055 | s->i++; |
| 1056 | if (s->i == s->block_aligned_filename_size) { |
| 1057 | printk(KERN_WARNING "%s: Invalid tag 70 packet; could not " |
| 1058 | "find valid separator between random characters and " |
| 1059 | "the filename\n", __func__); |
| 1060 | rc = -EINVAL; |
| 1061 | goto out_free_unlock; |
| 1062 | } |
| 1063 | s->i++; |
| 1064 | (*filename_size) = (s->block_aligned_filename_size - s->i); |
| 1065 | if (!((*filename_size) > 0 && (*filename_size < PATH_MAX))) { |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 1066 | printk(KERN_WARNING "%s: Filename size is [%zd], which is " |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1067 | "invalid\n", __func__, (*filename_size)); |
| 1068 | rc = -EINVAL; |
| 1069 | goto out_free_unlock; |
| 1070 | } |
| 1071 | (*filename) = kmalloc(((*filename_size) + 1), GFP_KERNEL); |
| 1072 | if (!(*filename)) { |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1073 | rc = -ENOMEM; |
| 1074 | goto out_free_unlock; |
| 1075 | } |
| 1076 | memcpy((*filename), &s->decrypted_filename[s->i], (*filename_size)); |
| 1077 | (*filename)[(*filename_size)] = '\0'; |
| 1078 | out_free_unlock: |
| 1079 | kfree(s->decrypted_filename); |
| 1080 | out_unlock: |
| 1081 | mutex_unlock(s->tfm_mutex); |
| 1082 | out: |
| 1083 | if (rc) { |
| 1084 | (*packet_size) = 0; |
| 1085 | (*filename_size) = 0; |
| 1086 | (*filename) = NULL; |
| 1087 | } |
Roberto Sassu | b5695d0 | 2011-03-21 16:00:55 +0100 | [diff] [blame] | 1088 | if (auth_tok_key) { |
| 1089 | up_write(&(auth_tok_key->sem)); |
Roberto Sassu | aee683b | 2010-10-06 18:31:06 +0200 | [diff] [blame] | 1090 | key_put(auth_tok_key); |
Roberto Sassu | b5695d0 | 2011-03-21 16:00:55 +0100 | [diff] [blame] | 1091 | } |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1092 | skcipher_request_free(s->skcipher_req); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1093 | kfree(s); |
| 1094 | return rc; |
| 1095 | } |
| 1096 | |
| 1097 | static int |
Michael Halcrow | cd9d67d | 2007-10-16 01:28:04 -0700 | [diff] [blame] | 1098 | ecryptfs_get_auth_tok_sig(char **sig, struct ecryptfs_auth_tok *auth_tok) |
| 1099 | { |
| 1100 | int rc = 0; |
| 1101 | |
| 1102 | (*sig) = NULL; |
| 1103 | switch (auth_tok->token_type) { |
| 1104 | case ECRYPTFS_PASSWORD: |
| 1105 | (*sig) = auth_tok->token.password.signature; |
| 1106 | break; |
| 1107 | case ECRYPTFS_PRIVATE_KEY: |
| 1108 | (*sig) = auth_tok->token.private_key.signature; |
| 1109 | break; |
| 1110 | default: |
| 1111 | printk(KERN_ERR "Cannot get sig for auth_tok of type [%d]\n", |
| 1112 | auth_tok->token_type); |
| 1113 | rc = -EINVAL; |
| 1114 | } |
| 1115 | return rc; |
| 1116 | } |
| 1117 | |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1118 | /** |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1119 | * decrypt_pki_encrypted_session_key - Decrypt the session key with the given auth_tok. |
| 1120 | * @auth_tok: The key authentication token used to decrypt the session key |
| 1121 | * @crypt_stat: The cryptographic context |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1122 | * |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1123 | * Returns zero on success; non-zero error otherwise. |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1124 | */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1125 | static int |
| 1126 | decrypt_pki_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok, |
| 1127 | struct ecryptfs_crypt_stat *crypt_stat) |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1128 | { |
Trevor Highland | 19e66a6 | 2008-02-06 01:38:36 -0800 | [diff] [blame] | 1129 | u8 cipher_code = 0; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1130 | struct ecryptfs_msg_ctx *msg_ctx; |
| 1131 | struct ecryptfs_message *msg = NULL; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1132 | char *auth_tok_sig; |
Geyslan G. Bem | 3edc837 | 2013-10-11 16:49:16 -0300 | [diff] [blame] | 1133 | char *payload = NULL; |
Simon Que | fa5199648 | 2013-01-17 11:18:20 -0800 | [diff] [blame] | 1134 | size_t payload_len = 0; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1135 | int rc; |
| 1136 | |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1137 | rc = ecryptfs_get_auth_tok_sig(&auth_tok_sig, auth_tok); |
| 1138 | if (rc) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1139 | printk(KERN_ERR "Unrecognized auth tok type: [%d]\n", |
| 1140 | auth_tok->token_type); |
| 1141 | goto out; |
| 1142 | } |
| 1143 | rc = write_tag_64_packet(auth_tok_sig, &(auth_tok->session_key), |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1144 | &payload, &payload_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1145 | if (rc) { |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1146 | ecryptfs_printk(KERN_ERR, "Failed to write tag 64 packet\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1147 | goto out; |
| 1148 | } |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1149 | rc = ecryptfs_send_message(payload, payload_len, &msg_ctx); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1150 | if (rc) { |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1151 | ecryptfs_printk(KERN_ERR, "Error sending message to " |
Kees Cook | 290502b | 2013-02-28 00:39:37 -0800 | [diff] [blame] | 1152 | "ecryptfsd: %d\n", rc); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1153 | goto out; |
| 1154 | } |
| 1155 | rc = ecryptfs_wait_for_response(msg_ctx, &msg); |
| 1156 | if (rc) { |
| 1157 | ecryptfs_printk(KERN_ERR, "Failed to receive tag 65 packet " |
| 1158 | "from the user space daemon\n"); |
| 1159 | rc = -EIO; |
| 1160 | goto out; |
| 1161 | } |
| 1162 | rc = parse_tag_65_packet(&(auth_tok->session_key), |
| 1163 | &cipher_code, msg); |
| 1164 | if (rc) { |
| 1165 | printk(KERN_ERR "Failed to parse tag 65 packet; rc = [%d]\n", |
| 1166 | rc); |
| 1167 | goto out; |
| 1168 | } |
| 1169 | auth_tok->session_key.flags |= ECRYPTFS_CONTAINS_DECRYPTED_KEY; |
| 1170 | memcpy(crypt_stat->key, auth_tok->session_key.decrypted_key, |
| 1171 | auth_tok->session_key.decrypted_key_size); |
| 1172 | crypt_stat->key_size = auth_tok->session_key.decrypted_key_size; |
| 1173 | rc = ecryptfs_cipher_code_to_string(crypt_stat->cipher, cipher_code); |
| 1174 | if (rc) { |
| 1175 | ecryptfs_printk(KERN_ERR, "Cipher code [%d] is invalid\n", |
Tom Rix | d0eb2d8 | 2020-11-27 08:05:13 -0800 | [diff] [blame] | 1176 | cipher_code); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1177 | goto out; |
| 1178 | } |
| 1179 | crypt_stat->flags |= ECRYPTFS_KEY_VALID; |
| 1180 | if (ecryptfs_verbosity > 0) { |
| 1181 | ecryptfs_printk(KERN_DEBUG, "Decrypted session key:\n"); |
| 1182 | ecryptfs_dump_hex(crypt_stat->key, |
| 1183 | crypt_stat->key_size); |
| 1184 | } |
| 1185 | out: |
Tim Gardner | 3a46741 | 2013-02-12 10:56:54 -0700 | [diff] [blame] | 1186 | kfree(msg); |
Geyslan G. Bem | 3edc837 | 2013-10-11 16:49:16 -0300 | [diff] [blame] | 1187 | kfree(payload); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1188 | return rc; |
| 1189 | } |
| 1190 | |
| 1191 | static void wipe_auth_tok_list(struct list_head *auth_tok_list_head) |
| 1192 | { |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1193 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item; |
Michael Halcrow | e0869cc | 2007-10-16 01:27:55 -0700 | [diff] [blame] | 1194 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item_tmp; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1195 | |
Michael Halcrow | e0869cc | 2007-10-16 01:27:55 -0700 | [diff] [blame] | 1196 | list_for_each_entry_safe(auth_tok_list_item, auth_tok_list_item_tmp, |
| 1197 | auth_tok_list_head, list) { |
| 1198 | list_del(&auth_tok_list_item->list); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1199 | kmem_cache_free(ecryptfs_auth_tok_list_item_cache, |
| 1200 | auth_tok_list_item); |
| 1201 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1202 | } |
| 1203 | |
| 1204 | struct kmem_cache *ecryptfs_auth_tok_list_item_cache; |
| 1205 | |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1206 | /** |
| 1207 | * parse_tag_1_packet |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1208 | * @crypt_stat: The cryptographic context to modify based on packet contents |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1209 | * @data: The raw bytes of the packet. |
| 1210 | * @auth_tok_list: eCryptfs parses packets into authentication tokens; |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1211 | * a new authentication token will be placed at the |
| 1212 | * end of this list for this packet. |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1213 | * @new_auth_tok: Pointer to a pointer to memory that this function |
| 1214 | * allocates; sets the memory address of the pointer to |
| 1215 | * NULL on error. This object is added to the |
| 1216 | * auth_tok_list. |
| 1217 | * @packet_size: This function writes the size of the parsed packet |
| 1218 | * into this memory location; zero on error. |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1219 | * @max_packet_size: The maximum allowable packet size |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1220 | * |
| 1221 | * Returns zero on success; non-zero on error. |
| 1222 | */ |
| 1223 | static int |
| 1224 | parse_tag_1_packet(struct ecryptfs_crypt_stat *crypt_stat, |
| 1225 | unsigned char *data, struct list_head *auth_tok_list, |
| 1226 | struct ecryptfs_auth_tok **new_auth_tok, |
| 1227 | size_t *packet_size, size_t max_packet_size) |
| 1228 | { |
| 1229 | size_t body_size; |
| 1230 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item; |
| 1231 | size_t length_size; |
| 1232 | int rc = 0; |
| 1233 | |
| 1234 | (*packet_size) = 0; |
| 1235 | (*new_auth_tok) = NULL; |
Michael Halcrow | 13218179 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1236 | /** |
| 1237 | * This format is inspired by OpenPGP; see RFC 2440 |
| 1238 | * packet tag 1 |
| 1239 | * |
| 1240 | * Tag 1 identifier (1 byte) |
| 1241 | * Max Tag 1 packet size (max 3 bytes) |
| 1242 | * Version (1 byte) |
| 1243 | * Key identifier (8 bytes; ECRYPTFS_SIG_SIZE) |
| 1244 | * Cipher identifier (1 byte) |
| 1245 | * Encrypted key size (arbitrary) |
| 1246 | * |
| 1247 | * 12 bytes minimum packet size |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1248 | */ |
Michael Halcrow | 13218179 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1249 | if (unlikely(max_packet_size < 12)) { |
| 1250 | printk(KERN_ERR "Invalid max packet size; must be >=12\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1251 | rc = -EINVAL; |
| 1252 | goto out; |
| 1253 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1254 | if (data[(*packet_size)++] != ECRYPTFS_TAG_1_PACKET_TYPE) { |
Michael Halcrow | 13218179 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1255 | printk(KERN_ERR "Enter w/ first byte != 0x%.2x\n", |
| 1256 | ECRYPTFS_TAG_1_PACKET_TYPE); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1257 | rc = -EINVAL; |
| 1258 | goto out; |
| 1259 | } |
| 1260 | /* Released: wipe_auth_tok_list called in ecryptfs_parse_packet_set or |
| 1261 | * at end of function upon failure */ |
| 1262 | auth_tok_list_item = |
Michael Halcrow | 13218179 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1263 | kmem_cache_zalloc(ecryptfs_auth_tok_list_item_cache, |
| 1264 | GFP_KERNEL); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1265 | if (!auth_tok_list_item) { |
Michael Halcrow | 13218179 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1266 | printk(KERN_ERR "Unable to allocate memory\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1267 | rc = -ENOMEM; |
| 1268 | goto out; |
| 1269 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1270 | (*new_auth_tok) = &auth_tok_list_item->auth_tok; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1271 | rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size, |
| 1272 | &length_size); |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1273 | if (rc) { |
Michael Halcrow | 13218179 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1274 | printk(KERN_WARNING "Error parsing packet length; " |
| 1275 | "rc = [%d]\n", rc); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1276 | goto out_free; |
| 1277 | } |
Michael Halcrow | 13218179 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1278 | if (unlikely(body_size < (ECRYPTFS_SIG_SIZE + 2))) { |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 1279 | printk(KERN_WARNING "Invalid body size ([%td])\n", body_size); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1280 | rc = -EINVAL; |
| 1281 | goto out_free; |
| 1282 | } |
| 1283 | (*packet_size) += length_size; |
| 1284 | if (unlikely((*packet_size) + body_size > max_packet_size)) { |
Michael Halcrow | 13218179 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1285 | printk(KERN_WARNING "Packet size exceeds max\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1286 | rc = -EINVAL; |
| 1287 | goto out_free; |
| 1288 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1289 | if (unlikely(data[(*packet_size)++] != 0x03)) { |
Michael Halcrow | 13218179 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1290 | printk(KERN_WARNING "Unknown version number [%d]\n", |
| 1291 | data[(*packet_size) - 1]); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1292 | rc = -EINVAL; |
| 1293 | goto out_free; |
| 1294 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1295 | ecryptfs_to_hex((*new_auth_tok)->token.private_key.signature, |
| 1296 | &data[(*packet_size)], ECRYPTFS_SIG_SIZE); |
| 1297 | *packet_size += ECRYPTFS_SIG_SIZE; |
| 1298 | /* This byte is skipped because the kernel does not need to |
| 1299 | * know which public key encryption algorithm was used */ |
| 1300 | (*packet_size)++; |
| 1301 | (*new_auth_tok)->session_key.encrypted_key_size = |
Michael Halcrow | 13218179 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1302 | body_size - (ECRYPTFS_SIG_SIZE + 2); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1303 | if ((*new_auth_tok)->session_key.encrypted_key_size |
| 1304 | > ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES) { |
Michael Halcrow | 13218179 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1305 | printk(KERN_WARNING "Tag 1 packet contains key larger " |
Colin Ian King | 0996b67 | 2016-09-27 05:18:02 -0700 | [diff] [blame] | 1306 | "than ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1307 | rc = -EINVAL; |
Wenwen Wang | fe2e082 | 2019-08-20 00:16:40 -0500 | [diff] [blame] | 1308 | goto out_free; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1309 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1310 | memcpy((*new_auth_tok)->session_key.encrypted_key, |
Michael Halcrow | 13218179 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1311 | &data[(*packet_size)], (body_size - (ECRYPTFS_SIG_SIZE + 2))); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1312 | (*packet_size) += (*new_auth_tok)->session_key.encrypted_key_size; |
| 1313 | (*new_auth_tok)->session_key.flags &= |
| 1314 | ~ECRYPTFS_CONTAINS_DECRYPTED_KEY; |
| 1315 | (*new_auth_tok)->session_key.flags |= |
| 1316 | ECRYPTFS_CONTAINS_ENCRYPTED_KEY; |
| 1317 | (*new_auth_tok)->token_type = ECRYPTFS_PRIVATE_KEY; |
Michael Halcrow | 13218179 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1318 | (*new_auth_tok)->flags = 0; |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1319 | (*new_auth_tok)->session_key.flags &= |
| 1320 | ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT); |
| 1321 | (*new_auth_tok)->session_key.flags &= |
| 1322 | ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1323 | list_add(&auth_tok_list_item->list, auth_tok_list); |
| 1324 | goto out; |
| 1325 | out_free: |
| 1326 | (*new_auth_tok) = NULL; |
| 1327 | memset(auth_tok_list_item, 0, |
| 1328 | sizeof(struct ecryptfs_auth_tok_list_item)); |
| 1329 | kmem_cache_free(ecryptfs_auth_tok_list_item_cache, |
| 1330 | auth_tok_list_item); |
| 1331 | out: |
| 1332 | if (rc) |
| 1333 | (*packet_size) = 0; |
| 1334 | return rc; |
| 1335 | } |
| 1336 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1337 | /** |
| 1338 | * parse_tag_3_packet |
| 1339 | * @crypt_stat: The cryptographic context to modify based on packet |
| 1340 | * contents. |
| 1341 | * @data: The raw bytes of the packet. |
| 1342 | * @auth_tok_list: eCryptfs parses packets into authentication tokens; |
| 1343 | * a new authentication token will be placed at the end |
| 1344 | * of this list for this packet. |
| 1345 | * @new_auth_tok: Pointer to a pointer to memory that this function |
| 1346 | * allocates; sets the memory address of the pointer to |
| 1347 | * NULL on error. This object is added to the |
| 1348 | * auth_tok_list. |
| 1349 | * @packet_size: This function writes the size of the parsed packet |
| 1350 | * into this memory location; zero on error. |
| 1351 | * @max_packet_size: maximum number of bytes to parse |
| 1352 | * |
| 1353 | * Returns zero on success; non-zero on error. |
| 1354 | */ |
| 1355 | static int |
| 1356 | parse_tag_3_packet(struct ecryptfs_crypt_stat *crypt_stat, |
| 1357 | unsigned char *data, struct list_head *auth_tok_list, |
| 1358 | struct ecryptfs_auth_tok **new_auth_tok, |
| 1359 | size_t *packet_size, size_t max_packet_size) |
| 1360 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1361 | size_t body_size; |
| 1362 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item; |
| 1363 | size_t length_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1364 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1365 | |
| 1366 | (*packet_size) = 0; |
| 1367 | (*new_auth_tok) = NULL; |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1368 | /** |
| 1369 | *This format is inspired by OpenPGP; see RFC 2440 |
| 1370 | * packet tag 3 |
| 1371 | * |
| 1372 | * Tag 3 identifier (1 byte) |
| 1373 | * Max Tag 3 packet size (max 3 bytes) |
| 1374 | * Version (1 byte) |
| 1375 | * Cipher code (1 byte) |
| 1376 | * S2K specifier (1 byte) |
| 1377 | * Hash identifier (1 byte) |
| 1378 | * Salt (ECRYPTFS_SALT_SIZE) |
| 1379 | * Hash iterations (1 byte) |
| 1380 | * Encrypted key (arbitrary) |
| 1381 | * |
| 1382 | * (ECRYPTFS_SALT_SIZE + 7) minimum packet size |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1383 | */ |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1384 | if (max_packet_size < (ECRYPTFS_SALT_SIZE + 7)) { |
| 1385 | printk(KERN_ERR "Max packet size too large\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1386 | rc = -EINVAL; |
| 1387 | goto out; |
| 1388 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1389 | if (data[(*packet_size)++] != ECRYPTFS_TAG_3_PACKET_TYPE) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1390 | printk(KERN_ERR "First byte != 0x%.2x; invalid packet\n", |
| 1391 | ECRYPTFS_TAG_3_PACKET_TYPE); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1392 | rc = -EINVAL; |
| 1393 | goto out; |
| 1394 | } |
| 1395 | /* Released: wipe_auth_tok_list called in ecryptfs_parse_packet_set or |
| 1396 | * at end of function upon failure */ |
| 1397 | auth_tok_list_item = |
Robert P. J. Day | c376222 | 2007-02-10 01:45:03 -0800 | [diff] [blame] | 1398 | kmem_cache_zalloc(ecryptfs_auth_tok_list_item_cache, GFP_KERNEL); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1399 | if (!auth_tok_list_item) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1400 | printk(KERN_ERR "Unable to allocate memory\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1401 | rc = -ENOMEM; |
| 1402 | goto out; |
| 1403 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1404 | (*new_auth_tok) = &auth_tok_list_item->auth_tok; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1405 | rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size, |
| 1406 | &length_size); |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1407 | if (rc) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1408 | printk(KERN_WARNING "Error parsing packet length; rc = [%d]\n", |
| 1409 | rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1410 | goto out_free; |
| 1411 | } |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1412 | if (unlikely(body_size < (ECRYPTFS_SALT_SIZE + 5))) { |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 1413 | printk(KERN_WARNING "Invalid body size ([%td])\n", body_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1414 | rc = -EINVAL; |
| 1415 | goto out_free; |
| 1416 | } |
| 1417 | (*packet_size) += length_size; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1418 | if (unlikely((*packet_size) + body_size > max_packet_size)) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1419 | printk(KERN_ERR "Packet size exceeds max\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1420 | rc = -EINVAL; |
| 1421 | goto out_free; |
| 1422 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1423 | (*new_auth_tok)->session_key.encrypted_key_size = |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1424 | (body_size - (ECRYPTFS_SALT_SIZE + 5)); |
Ramon de Carvalho Valle | f151cd2 | 2009-07-28 13:58:22 -0500 | [diff] [blame] | 1425 | if ((*new_auth_tok)->session_key.encrypted_key_size |
| 1426 | > ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES) { |
| 1427 | printk(KERN_WARNING "Tag 3 packet contains key larger " |
| 1428 | "than ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES\n"); |
| 1429 | rc = -EINVAL; |
| 1430 | goto out_free; |
| 1431 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1432 | if (unlikely(data[(*packet_size)++] != 0x04)) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1433 | printk(KERN_WARNING "Unknown version number [%d]\n", |
| 1434 | data[(*packet_size) - 1]); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1435 | rc = -EINVAL; |
| 1436 | goto out_free; |
| 1437 | } |
Tyler Hicks | b0105ea | 2009-08-11 00:36:32 -0500 | [diff] [blame] | 1438 | rc = ecryptfs_cipher_code_to_string(crypt_stat->cipher, |
| 1439 | (u16)data[(*packet_size)]); |
| 1440 | if (rc) |
| 1441 | goto out_free; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1442 | /* A little extra work to differentiate among the AES key |
| 1443 | * sizes; see RFC2440 */ |
| 1444 | switch(data[(*packet_size)++]) { |
| 1445 | case RFC2440_CIPHER_AES_192: |
| 1446 | crypt_stat->key_size = 24; |
| 1447 | break; |
| 1448 | default: |
| 1449 | crypt_stat->key_size = |
| 1450 | (*new_auth_tok)->session_key.encrypted_key_size; |
| 1451 | } |
Tyler Hicks | b0105ea | 2009-08-11 00:36:32 -0500 | [diff] [blame] | 1452 | rc = ecryptfs_init_crypt_ctx(crypt_stat); |
| 1453 | if (rc) |
| 1454 | goto out_free; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1455 | if (unlikely(data[(*packet_size)++] != 0x03)) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1456 | printk(KERN_WARNING "Only S2K ID 3 is currently supported\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1457 | rc = -ENOSYS; |
| 1458 | goto out_free; |
| 1459 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1460 | /* TODO: finish the hash mapping */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1461 | switch (data[(*packet_size)++]) { |
| 1462 | case 0x01: /* See RFC2440 for these numbers and their mappings */ |
| 1463 | /* Choose MD5 */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1464 | memcpy((*new_auth_tok)->token.password.salt, |
| 1465 | &data[(*packet_size)], ECRYPTFS_SALT_SIZE); |
| 1466 | (*packet_size) += ECRYPTFS_SALT_SIZE; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1467 | /* This conversion was taken straight from RFC2440 */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1468 | (*new_auth_tok)->token.password.hash_iterations = |
| 1469 | ((u32) 16 + (data[(*packet_size)] & 15)) |
| 1470 | << ((data[(*packet_size)] >> 4) + 6); |
| 1471 | (*packet_size)++; |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1472 | /* Friendly reminder: |
| 1473 | * (*new_auth_tok)->session_key.encrypted_key_size = |
| 1474 | * (body_size - (ECRYPTFS_SALT_SIZE + 5)); */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1475 | memcpy((*new_auth_tok)->session_key.encrypted_key, |
| 1476 | &data[(*packet_size)], |
| 1477 | (*new_auth_tok)->session_key.encrypted_key_size); |
| 1478 | (*packet_size) += |
| 1479 | (*new_auth_tok)->session_key.encrypted_key_size; |
| 1480 | (*new_auth_tok)->session_key.flags &= |
| 1481 | ~ECRYPTFS_CONTAINS_DECRYPTED_KEY; |
| 1482 | (*new_auth_tok)->session_key.flags |= |
| 1483 | ECRYPTFS_CONTAINS_ENCRYPTED_KEY; |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1484 | (*new_auth_tok)->token.password.hash_algo = 0x01; /* MD5 */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1485 | break; |
| 1486 | default: |
| 1487 | ecryptfs_printk(KERN_ERR, "Unsupported hash algorithm: " |
| 1488 | "[%d]\n", data[(*packet_size) - 1]); |
| 1489 | rc = -ENOSYS; |
| 1490 | goto out_free; |
| 1491 | } |
| 1492 | (*new_auth_tok)->token_type = ECRYPTFS_PASSWORD; |
| 1493 | /* TODO: Parametarize; we might actually want userspace to |
| 1494 | * decrypt the session key. */ |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1495 | (*new_auth_tok)->session_key.flags &= |
| 1496 | ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT); |
| 1497 | (*new_auth_tok)->session_key.flags &= |
| 1498 | ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1499 | list_add(&auth_tok_list_item->list, auth_tok_list); |
| 1500 | goto out; |
| 1501 | out_free: |
| 1502 | (*new_auth_tok) = NULL; |
| 1503 | memset(auth_tok_list_item, 0, |
| 1504 | sizeof(struct ecryptfs_auth_tok_list_item)); |
| 1505 | kmem_cache_free(ecryptfs_auth_tok_list_item_cache, |
| 1506 | auth_tok_list_item); |
| 1507 | out: |
| 1508 | if (rc) |
| 1509 | (*packet_size) = 0; |
| 1510 | return rc; |
| 1511 | } |
| 1512 | |
| 1513 | /** |
| 1514 | * parse_tag_11_packet |
| 1515 | * @data: The raw bytes of the packet |
| 1516 | * @contents: This function writes the data contents of the literal |
| 1517 | * packet into this memory location |
| 1518 | * @max_contents_bytes: The maximum number of bytes that this function |
| 1519 | * is allowed to write into contents |
| 1520 | * @tag_11_contents_size: This function writes the size of the parsed |
| 1521 | * contents into this memory location; zero on |
| 1522 | * error |
| 1523 | * @packet_size: This function writes the size of the parsed packet |
| 1524 | * into this memory location; zero on error |
| 1525 | * @max_packet_size: maximum number of bytes to parse |
| 1526 | * |
| 1527 | * Returns zero on success; non-zero on error. |
| 1528 | */ |
| 1529 | static int |
| 1530 | parse_tag_11_packet(unsigned char *data, unsigned char *contents, |
| 1531 | size_t max_contents_bytes, size_t *tag_11_contents_size, |
| 1532 | size_t *packet_size, size_t max_packet_size) |
| 1533 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1534 | size_t body_size; |
| 1535 | size_t length_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1536 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1537 | |
| 1538 | (*packet_size) = 0; |
| 1539 | (*tag_11_contents_size) = 0; |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1540 | /* This format is inspired by OpenPGP; see RFC 2440 |
| 1541 | * packet tag 11 |
| 1542 | * |
| 1543 | * Tag 11 identifier (1 byte) |
| 1544 | * Max Tag 11 packet size (max 3 bytes) |
| 1545 | * Binary format specifier (1 byte) |
| 1546 | * Filename length (1 byte) |
| 1547 | * Filename ("_CONSOLE") (8 bytes) |
| 1548 | * Modification date (4 bytes) |
| 1549 | * Literal data (arbitrary) |
| 1550 | * |
| 1551 | * We need at least 16 bytes of data for the packet to even be |
| 1552 | * valid. |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1553 | */ |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1554 | if (max_packet_size < 16) { |
| 1555 | printk(KERN_ERR "Maximum packet size too small\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1556 | rc = -EINVAL; |
| 1557 | goto out; |
| 1558 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1559 | if (data[(*packet_size)++] != ECRYPTFS_TAG_11_PACKET_TYPE) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1560 | printk(KERN_WARNING "Invalid tag 11 packet format\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1561 | rc = -EINVAL; |
| 1562 | goto out; |
| 1563 | } |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1564 | rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size, |
| 1565 | &length_size); |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1566 | if (rc) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1567 | printk(KERN_WARNING "Invalid tag 11 packet format\n"); |
| 1568 | goto out; |
| 1569 | } |
| 1570 | if (body_size < 14) { |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 1571 | printk(KERN_WARNING "Invalid body size ([%td])\n", body_size); |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1572 | rc = -EINVAL; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1573 | goto out; |
| 1574 | } |
| 1575 | (*packet_size) += length_size; |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1576 | (*tag_11_contents_size) = (body_size - 14); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1577 | if (unlikely((*packet_size) + body_size + 1 > max_packet_size)) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1578 | printk(KERN_ERR "Packet size exceeds max\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1579 | rc = -EINVAL; |
| 1580 | goto out; |
| 1581 | } |
Tyler Hicks | 6352a29 | 2009-07-28 13:57:01 -0500 | [diff] [blame] | 1582 | if (unlikely((*tag_11_contents_size) > max_contents_bytes)) { |
| 1583 | printk(KERN_ERR "Literal data section in tag 11 packet exceeds " |
| 1584 | "expected size\n"); |
| 1585 | rc = -EINVAL; |
| 1586 | goto out; |
| 1587 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1588 | if (data[(*packet_size)++] != 0x62) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1589 | printk(KERN_WARNING "Unrecognizable packet\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1590 | rc = -EINVAL; |
| 1591 | goto out; |
| 1592 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1593 | if (data[(*packet_size)++] != 0x08) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1594 | printk(KERN_WARNING "Unrecognizable packet\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1595 | rc = -EINVAL; |
| 1596 | goto out; |
| 1597 | } |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1598 | (*packet_size) += 12; /* Ignore filename and modification date */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1599 | memcpy(contents, &data[(*packet_size)], (*tag_11_contents_size)); |
| 1600 | (*packet_size) += (*tag_11_contents_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1601 | out: |
| 1602 | if (rc) { |
| 1603 | (*packet_size) = 0; |
| 1604 | (*tag_11_contents_size) = 0; |
| 1605 | } |
| 1606 | return rc; |
| 1607 | } |
| 1608 | |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1609 | int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key, |
| 1610 | struct ecryptfs_auth_tok **auth_tok, |
| 1611 | char *sig) |
| 1612 | { |
| 1613 | int rc = 0; |
| 1614 | |
Linus Torvalds | 028db3e | 2019-07-10 18:43:43 -0700 | [diff] [blame] | 1615 | (*auth_tok_key) = request_key(&key_type_user, sig, NULL); |
YueHaibing | 29a51df | 2019-05-27 21:28:14 +0800 | [diff] [blame] | 1616 | if (IS_ERR(*auth_tok_key)) { |
Roberto Sassu | 1252cc3 | 2011-06-27 13:45:45 +0200 | [diff] [blame] | 1617 | (*auth_tok_key) = ecryptfs_get_encrypted_key(sig); |
YueHaibing | 29a51df | 2019-05-27 21:28:14 +0800 | [diff] [blame] | 1618 | if (IS_ERR(*auth_tok_key)) { |
Roberto Sassu | 1252cc3 | 2011-06-27 13:45:45 +0200 | [diff] [blame] | 1619 | printk(KERN_ERR "Could not find key with description: [%s]\n", |
| 1620 | sig); |
| 1621 | rc = process_request_key_err(PTR_ERR(*auth_tok_key)); |
| 1622 | (*auth_tok_key) = NULL; |
| 1623 | goto out; |
| 1624 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1625 | } |
Roberto Sassu | b5695d0 | 2011-03-21 16:00:55 +0100 | [diff] [blame] | 1626 | down_write(&(*auth_tok_key)->sem); |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 1627 | rc = ecryptfs_verify_auth_tok_from_key(*auth_tok_key, auth_tok); |
Roberto Sassu | aee683b | 2010-10-06 18:31:06 +0200 | [diff] [blame] | 1628 | if (rc) { |
Roberto Sassu | b5695d0 | 2011-03-21 16:00:55 +0100 | [diff] [blame] | 1629 | up_write(&(*auth_tok_key)->sem); |
Roberto Sassu | aee683b | 2010-10-06 18:31:06 +0200 | [diff] [blame] | 1630 | key_put(*auth_tok_key); |
| 1631 | (*auth_tok_key) = NULL; |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 1632 | goto out; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1633 | } |
| 1634 | out: |
| 1635 | return rc; |
| 1636 | } |
| 1637 | |
| 1638 | /** |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1639 | * decrypt_passphrase_encrypted_session_key - Decrypt the session key with the given auth_tok. |
| 1640 | * @auth_tok: The passphrase authentication token to use to encrypt the FEK |
| 1641 | * @crypt_stat: The cryptographic context |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1642 | * |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1643 | * Returns zero on success; non-zero error otherwise |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1644 | */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1645 | static int |
| 1646 | decrypt_passphrase_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok, |
| 1647 | struct ecryptfs_crypt_stat *crypt_stat) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1648 | { |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 1649 | struct scatterlist dst_sg[2]; |
| 1650 | struct scatterlist src_sg[2]; |
Michael Halcrow | dd8e290 | 2007-10-16 01:28:03 -0700 | [diff] [blame] | 1651 | struct mutex *tfm_mutex; |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1652 | struct crypto_skcipher *tfm; |
| 1653 | struct skcipher_request *req = NULL; |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 1654 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1655 | |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1656 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 1657 | ecryptfs_printk( |
| 1658 | KERN_DEBUG, "Session key encryption key (size [%d]):\n", |
| 1659 | auth_tok->token.password.session_key_encryption_key_bytes); |
| 1660 | ecryptfs_dump_hex( |
| 1661 | auth_tok->token.password.session_key_encryption_key, |
| 1662 | auth_tok->token.password.session_key_encryption_key_bytes); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1663 | } |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1664 | rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(&tfm, &tfm_mutex, |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1665 | crypt_stat->cipher); |
| 1666 | if (unlikely(rc)) { |
| 1667 | printk(KERN_ERR "Internal error whilst attempting to get " |
| 1668 | "tfm and mutex for cipher name [%s]; rc = [%d]\n", |
| 1669 | crypt_stat->cipher, rc); |
| 1670 | goto out; |
| 1671 | } |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1672 | rc = virt_to_scatterlist(auth_tok->session_key.encrypted_key, |
| 1673 | auth_tok->session_key.encrypted_key_size, |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 1674 | src_sg, 2); |
| 1675 | if (rc < 1 || rc > 2) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1676 | printk(KERN_ERR "Internal error whilst attempting to convert " |
| 1677 | "auth_tok->session_key.encrypted_key to scatterlist; " |
| 1678 | "expected rc = 1; got rc = [%d]. " |
| 1679 | "auth_tok->session_key.encrypted_key_size = [%d]\n", rc, |
| 1680 | auth_tok->session_key.encrypted_key_size); |
| 1681 | goto out; |
| 1682 | } |
| 1683 | auth_tok->session_key.decrypted_key_size = |
| 1684 | auth_tok->session_key.encrypted_key_size; |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1685 | rc = virt_to_scatterlist(auth_tok->session_key.decrypted_key, |
| 1686 | auth_tok->session_key.decrypted_key_size, |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 1687 | dst_sg, 2); |
| 1688 | if (rc < 1 || rc > 2) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1689 | printk(KERN_ERR "Internal error whilst attempting to convert " |
| 1690 | "auth_tok->session_key.decrypted_key to scatterlist; " |
| 1691 | "expected rc = 1; got rc = [%d]\n", rc); |
| 1692 | goto out; |
| 1693 | } |
| 1694 | mutex_lock(tfm_mutex); |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1695 | req = skcipher_request_alloc(tfm, GFP_KERNEL); |
| 1696 | if (!req) { |
| 1697 | mutex_unlock(tfm_mutex); |
| 1698 | printk(KERN_ERR "%s: Out of kernel memory whilst attempting to " |
| 1699 | "skcipher_request_alloc for %s\n", __func__, |
| 1700 | crypto_skcipher_driver_name(tfm)); |
| 1701 | rc = -ENOMEM; |
| 1702 | goto out; |
| 1703 | } |
| 1704 | |
| 1705 | skcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, |
| 1706 | NULL, NULL); |
| 1707 | rc = crypto_skcipher_setkey( |
| 1708 | tfm, auth_tok->token.password.session_key_encryption_key, |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1709 | crypt_stat->key_size); |
| 1710 | if (unlikely(rc < 0)) { |
| 1711 | mutex_unlock(tfm_mutex); |
Michael Halcrow | e5d9cbd | 2006-10-30 22:07:16 -0800 | [diff] [blame] | 1712 | printk(KERN_ERR "Error setting key for crypto context\n"); |
| 1713 | rc = -EINVAL; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1714 | goto out; |
Michael Halcrow | e5d9cbd | 2006-10-30 22:07:16 -0800 | [diff] [blame] | 1715 | } |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1716 | skcipher_request_set_crypt(req, src_sg, dst_sg, |
| 1717 | auth_tok->session_key.encrypted_key_size, |
| 1718 | NULL); |
| 1719 | rc = crypto_skcipher_decrypt(req); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1720 | mutex_unlock(tfm_mutex); |
| 1721 | if (unlikely(rc)) { |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 1722 | printk(KERN_ERR "Error decrypting; rc = [%d]\n", rc); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1723 | goto out; |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 1724 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1725 | auth_tok->session_key.flags |= ECRYPTFS_CONTAINS_DECRYPTED_KEY; |
| 1726 | memcpy(crypt_stat->key, auth_tok->session_key.decrypted_key, |
| 1727 | auth_tok->session_key.decrypted_key_size); |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1728 | crypt_stat->flags |= ECRYPTFS_KEY_VALID; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1729 | if (unlikely(ecryptfs_verbosity > 0)) { |
Tyler Hicks | f24b388 | 2010-11-15 17:36:38 -0600 | [diff] [blame] | 1730 | ecryptfs_printk(KERN_DEBUG, "FEK of size [%zd]:\n", |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1731 | crypt_stat->key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1732 | ecryptfs_dump_hex(crypt_stat->key, |
| 1733 | crypt_stat->key_size); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1734 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1735 | out: |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1736 | skcipher_request_free(req); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1737 | return rc; |
| 1738 | } |
| 1739 | |
| 1740 | /** |
| 1741 | * ecryptfs_parse_packet_set |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1742 | * @crypt_stat: The cryptographic context |
| 1743 | * @src: Virtual address of region of memory containing the packets |
| 1744 | * @ecryptfs_dentry: The eCryptfs dentry associated with the packet set |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1745 | * |
| 1746 | * Get crypt_stat to have the file's session key if the requisite key |
| 1747 | * is available to decrypt the session key. |
| 1748 | * |
| 1749 | * Returns Zero if a valid authentication token was retrieved and |
| 1750 | * processed; negative value for file not encrypted or for error |
| 1751 | * conditions. |
| 1752 | */ |
| 1753 | int ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat, |
| 1754 | unsigned char *src, |
| 1755 | struct dentry *ecryptfs_dentry) |
| 1756 | { |
| 1757 | size_t i = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1758 | size_t found_auth_tok; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1759 | size_t next_packet_is_auth_tok_packet; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1760 | struct list_head auth_tok_list; |
Michael Halcrow | dd8e290 | 2007-10-16 01:28:03 -0700 | [diff] [blame] | 1761 | struct ecryptfs_auth_tok *matching_auth_tok; |
| 1762 | struct ecryptfs_auth_tok *candidate_auth_tok; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1763 | char *candidate_auth_tok_sig; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1764 | size_t packet_size; |
| 1765 | struct ecryptfs_auth_tok *new_auth_tok; |
| 1766 | unsigned char sig_tmp_space[ECRYPTFS_SIG_SIZE]; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1767 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1768 | size_t tag_11_contents_size; |
| 1769 | size_t tag_11_packet_size; |
Roberto Sassu | aee683b | 2010-10-06 18:31:06 +0200 | [diff] [blame] | 1770 | struct key *auth_tok_key = NULL; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1771 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1772 | |
| 1773 | INIT_LIST_HEAD(&auth_tok_list); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1774 | /* Parse the header to find as many packets as we can; these will be |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1775 | * added the our &auth_tok_list */ |
| 1776 | next_packet_is_auth_tok_packet = 1; |
| 1777 | while (next_packet_is_auth_tok_packet) { |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 1778 | size_t max_packet_size = ((PAGE_SIZE - 8) - i); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1779 | |
| 1780 | switch (src[i]) { |
| 1781 | case ECRYPTFS_TAG_3_PACKET_TYPE: |
| 1782 | rc = parse_tag_3_packet(crypt_stat, |
| 1783 | (unsigned char *)&src[i], |
| 1784 | &auth_tok_list, &new_auth_tok, |
| 1785 | &packet_size, max_packet_size); |
| 1786 | if (rc) { |
| 1787 | ecryptfs_printk(KERN_ERR, "Error parsing " |
| 1788 | "tag 3 packet\n"); |
| 1789 | rc = -EIO; |
| 1790 | goto out_wipe_list; |
| 1791 | } |
| 1792 | i += packet_size; |
| 1793 | rc = parse_tag_11_packet((unsigned char *)&src[i], |
| 1794 | sig_tmp_space, |
| 1795 | ECRYPTFS_SIG_SIZE, |
| 1796 | &tag_11_contents_size, |
| 1797 | &tag_11_packet_size, |
| 1798 | max_packet_size); |
| 1799 | if (rc) { |
| 1800 | ecryptfs_printk(KERN_ERR, "No valid " |
| 1801 | "(ecryptfs-specific) literal " |
| 1802 | "packet containing " |
| 1803 | "authentication token " |
| 1804 | "signature found after " |
| 1805 | "tag 3 packet\n"); |
| 1806 | rc = -EIO; |
| 1807 | goto out_wipe_list; |
| 1808 | } |
| 1809 | i += tag_11_packet_size; |
| 1810 | if (ECRYPTFS_SIG_SIZE != tag_11_contents_size) { |
| 1811 | ecryptfs_printk(KERN_ERR, "Expected " |
| 1812 | "signature of size [%d]; " |
Tyler Hicks | f24b388 | 2010-11-15 17:36:38 -0600 | [diff] [blame] | 1813 | "read size [%zd]\n", |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1814 | ECRYPTFS_SIG_SIZE, |
| 1815 | tag_11_contents_size); |
| 1816 | rc = -EIO; |
| 1817 | goto out_wipe_list; |
| 1818 | } |
| 1819 | ecryptfs_to_hex(new_auth_tok->token.password.signature, |
| 1820 | sig_tmp_space, tag_11_contents_size); |
| 1821 | new_auth_tok->token.password.signature[ |
| 1822 | ECRYPTFS_PASSWORD_SIG_SIZE] = '\0'; |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1823 | crypt_stat->flags |= ECRYPTFS_ENCRYPTED; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1824 | break; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1825 | case ECRYPTFS_TAG_1_PACKET_TYPE: |
| 1826 | rc = parse_tag_1_packet(crypt_stat, |
| 1827 | (unsigned char *)&src[i], |
| 1828 | &auth_tok_list, &new_auth_tok, |
| 1829 | &packet_size, max_packet_size); |
| 1830 | if (rc) { |
| 1831 | ecryptfs_printk(KERN_ERR, "Error parsing " |
| 1832 | "tag 1 packet\n"); |
| 1833 | rc = -EIO; |
| 1834 | goto out_wipe_list; |
| 1835 | } |
| 1836 | i += packet_size; |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1837 | crypt_stat->flags |= ECRYPTFS_ENCRYPTED; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1838 | break; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1839 | case ECRYPTFS_TAG_11_PACKET_TYPE: |
| 1840 | ecryptfs_printk(KERN_WARNING, "Invalid packet set " |
| 1841 | "(Tag 11 not allowed by itself)\n"); |
| 1842 | rc = -EIO; |
| 1843 | goto out_wipe_list; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1844 | default: |
Tyler Hicks | f24b388 | 2010-11-15 17:36:38 -0600 | [diff] [blame] | 1845 | ecryptfs_printk(KERN_DEBUG, "No packet at offset [%zd] " |
| 1846 | "of the file header; hex value of " |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1847 | "character is [0x%.2x]\n", i, src[i]); |
| 1848 | next_packet_is_auth_tok_packet = 0; |
| 1849 | } |
| 1850 | } |
| 1851 | if (list_empty(&auth_tok_list)) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1852 | printk(KERN_ERR "The lower file appears to be a non-encrypted " |
| 1853 | "eCryptfs file; this is not supported in this version " |
| 1854 | "of the eCryptfs kernel module\n"); |
| 1855 | rc = -EINVAL; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1856 | goto out; |
| 1857 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1858 | /* auth_tok_list contains the set of authentication tokens |
| 1859 | * parsed from the metadata. We need to find a matching |
| 1860 | * authentication token that has the secret component(s) |
| 1861 | * necessary to decrypt the EFEK in the auth_tok parsed from |
| 1862 | * the metadata. There may be several potential matches, but |
| 1863 | * just one will be sufficient to decrypt to get the FEK. */ |
| 1864 | find_next_matching_auth_tok: |
| 1865 | found_auth_tok = 0; |
| 1866 | list_for_each_entry(auth_tok_list_item, &auth_tok_list, list) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1867 | candidate_auth_tok = &auth_tok_list_item->auth_tok; |
| 1868 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 1869 | ecryptfs_printk(KERN_DEBUG, |
Colin Ian King | f62fd7a | 2018-03-02 09:07:08 +0000 | [diff] [blame] | 1870 | "Considering candidate auth tok:\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1871 | ecryptfs_dump_auth_tok(candidate_auth_tok); |
| 1872 | } |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1873 | rc = ecryptfs_get_auth_tok_sig(&candidate_auth_tok_sig, |
| 1874 | candidate_auth_tok); |
| 1875 | if (rc) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1876 | printk(KERN_ERR |
| 1877 | "Unrecognized candidate auth tok type: [%d]\n", |
| 1878 | candidate_auth_tok->token_type); |
| 1879 | rc = -EINVAL; |
| 1880 | goto out_wipe_list; |
| 1881 | } |
Roberto Sassu | 39fac85 | 2010-10-06 18:31:15 +0200 | [diff] [blame] | 1882 | rc = ecryptfs_find_auth_tok_for_sig(&auth_tok_key, |
Roberto Sassu | aee683b | 2010-10-06 18:31:06 +0200 | [diff] [blame] | 1883 | &matching_auth_tok, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1884 | crypt_stat->mount_crypt_stat, |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1885 | candidate_auth_tok_sig); |
Roberto Sassu | 39fac85 | 2010-10-06 18:31:15 +0200 | [diff] [blame] | 1886 | if (!rc) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1887 | found_auth_tok = 1; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1888 | goto found_matching_auth_tok; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1889 | } |
| 1890 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1891 | if (!found_auth_tok) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1892 | ecryptfs_printk(KERN_ERR, "Could not find a usable " |
| 1893 | "authentication token\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1894 | rc = -EIO; |
| 1895 | goto out_wipe_list; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1896 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1897 | found_matching_auth_tok: |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1898 | if (candidate_auth_tok->token_type == ECRYPTFS_PRIVATE_KEY) { |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1899 | memcpy(&(candidate_auth_tok->token.private_key), |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1900 | &(matching_auth_tok->token.private_key), |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1901 | sizeof(struct ecryptfs_private_key)); |
Tyler Hicks | b2987a5 | 2011-07-26 19:47:08 -0500 | [diff] [blame] | 1902 | up_write(&(auth_tok_key->sem)); |
| 1903 | key_put(auth_tok_key); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1904 | rc = decrypt_pki_encrypted_session_key(candidate_auth_tok, |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1905 | crypt_stat); |
| 1906 | } else if (candidate_auth_tok->token_type == ECRYPTFS_PASSWORD) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1907 | memcpy(&(candidate_auth_tok->token.password), |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1908 | &(matching_auth_tok->token.password), |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1909 | sizeof(struct ecryptfs_password)); |
Tyler Hicks | b2987a5 | 2011-07-26 19:47:08 -0500 | [diff] [blame] | 1910 | up_write(&(auth_tok_key->sem)); |
| 1911 | key_put(auth_tok_key); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1912 | rc = decrypt_passphrase_encrypted_session_key( |
| 1913 | candidate_auth_tok, crypt_stat); |
Tyler Hicks | b2987a5 | 2011-07-26 19:47:08 -0500 | [diff] [blame] | 1914 | } else { |
| 1915 | up_write(&(auth_tok_key->sem)); |
| 1916 | key_put(auth_tok_key); |
| 1917 | rc = -EINVAL; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1918 | } |
| 1919 | if (rc) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1920 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item_tmp; |
| 1921 | |
| 1922 | ecryptfs_printk(KERN_WARNING, "Error decrypting the " |
| 1923 | "session key for authentication token with sig " |
| 1924 | "[%.*s]; rc = [%d]. Removing auth tok " |
| 1925 | "candidate from the list and searching for " |
Joe Perches | 888d57b | 2010-11-10 15:46:16 -0800 | [diff] [blame] | 1926 | "the next match.\n", ECRYPTFS_SIG_SIZE_HEX, |
| 1927 | candidate_auth_tok_sig, rc); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1928 | list_for_each_entry_safe(auth_tok_list_item, |
| 1929 | auth_tok_list_item_tmp, |
| 1930 | &auth_tok_list, list) { |
| 1931 | if (candidate_auth_tok |
| 1932 | == &auth_tok_list_item->auth_tok) { |
| 1933 | list_del(&auth_tok_list_item->list); |
| 1934 | kmem_cache_free( |
| 1935 | ecryptfs_auth_tok_list_item_cache, |
| 1936 | auth_tok_list_item); |
| 1937 | goto find_next_matching_auth_tok; |
| 1938 | } |
| 1939 | } |
| 1940 | BUG(); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1941 | } |
| 1942 | rc = ecryptfs_compute_root_iv(crypt_stat); |
| 1943 | if (rc) { |
| 1944 | ecryptfs_printk(KERN_ERR, "Error computing " |
| 1945 | "the root IV\n"); |
| 1946 | goto out_wipe_list; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1947 | } |
| 1948 | rc = ecryptfs_init_crypt_ctx(crypt_stat); |
| 1949 | if (rc) { |
| 1950 | ecryptfs_printk(KERN_ERR, "Error initializing crypto " |
| 1951 | "context for cipher [%s]; rc = [%d]\n", |
| 1952 | crypt_stat->cipher, rc); |
| 1953 | } |
| 1954 | out_wipe_list: |
| 1955 | wipe_auth_tok_list(&auth_tok_list); |
| 1956 | out: |
| 1957 | return rc; |
| 1958 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1959 | |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1960 | static int |
Tyler Hicks | b2987a5 | 2011-07-26 19:47:08 -0500 | [diff] [blame] | 1961 | pki_encrypt_session_key(struct key *auth_tok_key, |
| 1962 | struct ecryptfs_auth_tok *auth_tok, |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1963 | struct ecryptfs_crypt_stat *crypt_stat, |
| 1964 | struct ecryptfs_key_record *key_rec) |
| 1965 | { |
| 1966 | struct ecryptfs_msg_ctx *msg_ctx = NULL; |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1967 | char *payload = NULL; |
Tyler Hicks | 99b373ff | 2011-08-05 04:15:19 -0500 | [diff] [blame] | 1968 | size_t payload_len = 0; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1969 | struct ecryptfs_message *msg; |
| 1970 | int rc; |
| 1971 | |
| 1972 | rc = write_tag_66_packet(auth_tok->token.private_key.signature, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1973 | ecryptfs_code_for_cipher_string( |
| 1974 | crypt_stat->cipher, |
| 1975 | crypt_stat->key_size), |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1976 | crypt_stat, &payload, &payload_len); |
Tyler Hicks | b2987a5 | 2011-07-26 19:47:08 -0500 | [diff] [blame] | 1977 | up_write(&(auth_tok_key->sem)); |
| 1978 | key_put(auth_tok_key); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1979 | if (rc) { |
| 1980 | ecryptfs_printk(KERN_ERR, "Error generating tag 66 packet\n"); |
| 1981 | goto out; |
| 1982 | } |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1983 | rc = ecryptfs_send_message(payload, payload_len, &msg_ctx); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1984 | if (rc) { |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1985 | ecryptfs_printk(KERN_ERR, "Error sending message to " |
Kees Cook | 290502b | 2013-02-28 00:39:37 -0800 | [diff] [blame] | 1986 | "ecryptfsd: %d\n", rc); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1987 | goto out; |
| 1988 | } |
| 1989 | rc = ecryptfs_wait_for_response(msg_ctx, &msg); |
| 1990 | if (rc) { |
| 1991 | ecryptfs_printk(KERN_ERR, "Failed to receive tag 67 packet " |
| 1992 | "from the user space daemon\n"); |
| 1993 | rc = -EIO; |
| 1994 | goto out; |
| 1995 | } |
| 1996 | rc = parse_tag_67_packet(key_rec, msg); |
| 1997 | if (rc) |
| 1998 | ecryptfs_printk(KERN_ERR, "Error parsing tag 67 packet\n"); |
| 1999 | kfree(msg); |
| 2000 | out: |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 2001 | kfree(payload); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2002 | return rc; |
| 2003 | } |
| 2004 | /** |
| 2005 | * write_tag_1_packet - Write an RFC2440-compatible tag 1 (public key) packet |
| 2006 | * @dest: Buffer into which to write the packet |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 2007 | * @remaining_bytes: Maximum number of bytes that can be writtn |
Tyler Hicks | b2987a5 | 2011-07-26 19:47:08 -0500 | [diff] [blame] | 2008 | * @auth_tok_key: The authentication token key to unlock and put when done with |
| 2009 | * @auth_tok |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 2010 | * @auth_tok: The authentication token used for generating the tag 1 packet |
| 2011 | * @crypt_stat: The cryptographic context |
| 2012 | * @key_rec: The key record struct for the tag 1 packet |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2013 | * @packet_size: This function will write the number of bytes that end |
| 2014 | * up constituting the packet; set to zero on error |
| 2015 | * |
| 2016 | * Returns zero on success; non-zero on error. |
| 2017 | */ |
| 2018 | static int |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2019 | write_tag_1_packet(char *dest, size_t *remaining_bytes, |
Tyler Hicks | b2987a5 | 2011-07-26 19:47:08 -0500 | [diff] [blame] | 2020 | struct key *auth_tok_key, struct ecryptfs_auth_tok *auth_tok, |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2021 | struct ecryptfs_crypt_stat *crypt_stat, |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2022 | struct ecryptfs_key_record *key_rec, size_t *packet_size) |
| 2023 | { |
| 2024 | size_t i; |
| 2025 | size_t encrypted_session_key_valid = 0; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2026 | size_t packet_size_length; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2027 | size_t max_packet_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2028 | int rc = 0; |
| 2029 | |
| 2030 | (*packet_size) = 0; |
| 2031 | ecryptfs_from_hex(key_rec->sig, auth_tok->token.private_key.signature, |
| 2032 | ECRYPTFS_SIG_SIZE); |
| 2033 | encrypted_session_key_valid = 0; |
| 2034 | for (i = 0; i < crypt_stat->key_size; i++) |
| 2035 | encrypted_session_key_valid |= |
| 2036 | auth_tok->session_key.encrypted_key[i]; |
| 2037 | if (encrypted_session_key_valid) { |
| 2038 | memcpy(key_rec->enc_key, |
| 2039 | auth_tok->session_key.encrypted_key, |
| 2040 | auth_tok->session_key.encrypted_key_size); |
Tyler Hicks | b2987a5 | 2011-07-26 19:47:08 -0500 | [diff] [blame] | 2041 | up_write(&(auth_tok_key->sem)); |
| 2042 | key_put(auth_tok_key); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2043 | goto encrypted_session_key_set; |
| 2044 | } |
| 2045 | if (auth_tok->session_key.encrypted_key_size == 0) |
| 2046 | auth_tok->session_key.encrypted_key_size = |
| 2047 | auth_tok->token.private_key.key_size; |
Tyler Hicks | b2987a5 | 2011-07-26 19:47:08 -0500 | [diff] [blame] | 2048 | rc = pki_encrypt_session_key(auth_tok_key, auth_tok, crypt_stat, |
| 2049 | key_rec); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2050 | if (rc) { |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 2051 | printk(KERN_ERR "Failed to encrypt session key via a key " |
| 2052 | "module; rc = [%d]\n", rc); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2053 | goto out; |
| 2054 | } |
| 2055 | if (ecryptfs_verbosity > 0) { |
| 2056 | ecryptfs_printk(KERN_DEBUG, "Encrypted key:\n"); |
| 2057 | ecryptfs_dump_hex(key_rec->enc_key, key_rec->enc_key_size); |
| 2058 | } |
| 2059 | encrypted_session_key_set: |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2060 | /* This format is inspired by OpenPGP; see RFC 2440 |
| 2061 | * packet tag 1 */ |
| 2062 | max_packet_size = (1 /* Tag 1 identifier */ |
| 2063 | + 3 /* Max Tag 1 packet size */ |
| 2064 | + 1 /* Version */ |
| 2065 | + ECRYPTFS_SIG_SIZE /* Key identifier */ |
| 2066 | + 1 /* Cipher identifier */ |
| 2067 | + key_rec->enc_key_size); /* Encrypted key size */ |
| 2068 | if (max_packet_size > (*remaining_bytes)) { |
| 2069 | printk(KERN_ERR "Packet length larger than maximum allowable; " |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 2070 | "need up to [%td] bytes, but there are only [%td] " |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2071 | "available\n", max_packet_size, (*remaining_bytes)); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2072 | rc = -EINVAL; |
| 2073 | goto out; |
| 2074 | } |
| 2075 | dest[(*packet_size)++] = ECRYPTFS_TAG_1_PACKET_TYPE; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 2076 | rc = ecryptfs_write_packet_length(&dest[(*packet_size)], |
| 2077 | (max_packet_size - 4), |
| 2078 | &packet_size_length); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2079 | if (rc) { |
| 2080 | ecryptfs_printk(KERN_ERR, "Error generating tag 1 packet " |
| 2081 | "header; cannot generate packet length\n"); |
| 2082 | goto out; |
| 2083 | } |
| 2084 | (*packet_size) += packet_size_length; |
| 2085 | dest[(*packet_size)++] = 0x03; /* version 3 */ |
| 2086 | memcpy(&dest[(*packet_size)], key_rec->sig, ECRYPTFS_SIG_SIZE); |
| 2087 | (*packet_size) += ECRYPTFS_SIG_SIZE; |
| 2088 | dest[(*packet_size)++] = RFC2440_CIPHER_RSA; |
| 2089 | memcpy(&dest[(*packet_size)], key_rec->enc_key, |
| 2090 | key_rec->enc_key_size); |
| 2091 | (*packet_size) += key_rec->enc_key_size; |
| 2092 | out: |
| 2093 | if (rc) |
| 2094 | (*packet_size) = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2095 | else |
| 2096 | (*remaining_bytes) -= (*packet_size); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2097 | return rc; |
| 2098 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2099 | |
| 2100 | /** |
| 2101 | * write_tag_11_packet |
| 2102 | * @dest: Target into which Tag 11 packet is to be written |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 2103 | * @remaining_bytes: Maximum packet length |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2104 | * @contents: Byte array of contents to copy in |
| 2105 | * @contents_length: Number of bytes in contents |
| 2106 | * @packet_length: Length of the Tag 11 packet written; zero on error |
| 2107 | * |
| 2108 | * Returns zero on success; non-zero on error. |
| 2109 | */ |
| 2110 | static int |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 2111 | write_tag_11_packet(char *dest, size_t *remaining_bytes, char *contents, |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2112 | size_t contents_length, size_t *packet_length) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2113 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2114 | size_t packet_size_length; |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2115 | size_t max_packet_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2116 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2117 | |
| 2118 | (*packet_length) = 0; |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2119 | /* This format is inspired by OpenPGP; see RFC 2440 |
| 2120 | * packet tag 11 */ |
| 2121 | max_packet_size = (1 /* Tag 11 identifier */ |
| 2122 | + 3 /* Max Tag 11 packet size */ |
| 2123 | + 1 /* Binary format specifier */ |
| 2124 | + 1 /* Filename length */ |
| 2125 | + 8 /* Filename ("_CONSOLE") */ |
| 2126 | + 4 /* Modification date */ |
| 2127 | + contents_length); /* Literal data */ |
| 2128 | if (max_packet_size > (*remaining_bytes)) { |
| 2129 | printk(KERN_ERR "Packet length larger than maximum allowable; " |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 2130 | "need up to [%td] bytes, but there are only [%td] " |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2131 | "available\n", max_packet_size, (*remaining_bytes)); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2132 | rc = -EINVAL; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2133 | goto out; |
| 2134 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2135 | dest[(*packet_length)++] = ECRYPTFS_TAG_11_PACKET_TYPE; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 2136 | rc = ecryptfs_write_packet_length(&dest[(*packet_length)], |
| 2137 | (max_packet_size - 4), |
| 2138 | &packet_size_length); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2139 | if (rc) { |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2140 | printk(KERN_ERR "Error generating tag 11 packet header; cannot " |
| 2141 | "generate packet length. rc = [%d]\n", rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2142 | goto out; |
| 2143 | } |
| 2144 | (*packet_length) += packet_size_length; |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2145 | dest[(*packet_length)++] = 0x62; /* binary data format specifier */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2146 | dest[(*packet_length)++] = 8; |
| 2147 | memcpy(&dest[(*packet_length)], "_CONSOLE", 8); |
| 2148 | (*packet_length) += 8; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2149 | memset(&dest[(*packet_length)], 0x00, 4); |
| 2150 | (*packet_length) += 4; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2151 | memcpy(&dest[(*packet_length)], contents, contents_length); |
| 2152 | (*packet_length) += contents_length; |
| 2153 | out: |
| 2154 | if (rc) |
| 2155 | (*packet_length) = 0; |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2156 | else |
| 2157 | (*remaining_bytes) -= (*packet_length); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2158 | return rc; |
| 2159 | } |
| 2160 | |
| 2161 | /** |
| 2162 | * write_tag_3_packet |
| 2163 | * @dest: Buffer into which to write the packet |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 2164 | * @remaining_bytes: Maximum number of bytes that can be written |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2165 | * @auth_tok: Authentication token |
| 2166 | * @crypt_stat: The cryptographic context |
| 2167 | * @key_rec: encrypted key |
| 2168 | * @packet_size: This function will write the number of bytes that end |
| 2169 | * up constituting the packet; set to zero on error |
| 2170 | * |
| 2171 | * Returns zero on success; non-zero on error. |
| 2172 | */ |
| 2173 | static int |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2174 | write_tag_3_packet(char *dest, size_t *remaining_bytes, |
| 2175 | struct ecryptfs_auth_tok *auth_tok, |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2176 | struct ecryptfs_crypt_stat *crypt_stat, |
| 2177 | struct ecryptfs_key_record *key_rec, size_t *packet_size) |
| 2178 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2179 | size_t i; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2180 | size_t encrypted_session_key_valid = 0; |
| 2181 | char session_key_encryption_key[ECRYPTFS_MAX_KEY_BYTES]; |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 2182 | struct scatterlist dst_sg[2]; |
| 2183 | struct scatterlist src_sg[2]; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2184 | struct mutex *tfm_mutex = NULL; |
Trevor Highland | 19e66a6 | 2008-02-06 01:38:36 -0800 | [diff] [blame] | 2185 | u8 cipher_code; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2186 | size_t packet_size_length; |
| 2187 | size_t max_packet_size; |
| 2188 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat = |
| 2189 | crypt_stat->mount_crypt_stat; |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 2190 | struct crypto_skcipher *tfm; |
| 2191 | struct skcipher_request *req; |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 2192 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2193 | |
| 2194 | (*packet_size) = 0; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2195 | ecryptfs_from_hex(key_rec->sig, auth_tok->token.password.signature, |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2196 | ECRYPTFS_SIG_SIZE); |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 2197 | rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(&tfm, &tfm_mutex, |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2198 | crypt_stat->cipher); |
| 2199 | if (unlikely(rc)) { |
| 2200 | printk(KERN_ERR "Internal error whilst attempting to get " |
| 2201 | "tfm and mutex for cipher name [%s]; rc = [%d]\n", |
| 2202 | crypt_stat->cipher, rc); |
| 2203 | goto out; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2204 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2205 | if (mount_crypt_stat->global_default_cipher_key_size == 0) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2206 | printk(KERN_WARNING "No key size specified at mount; " |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 2207 | "defaulting to [%d]\n", |
Eric Biggers | 9ac0d13 | 2019-11-29 10:23:04 -0800 | [diff] [blame] | 2208 | crypto_skcipher_max_keysize(tfm)); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2209 | mount_crypt_stat->global_default_cipher_key_size = |
Eric Biggers | 9ac0d13 | 2019-11-29 10:23:04 -0800 | [diff] [blame] | 2210 | crypto_skcipher_max_keysize(tfm); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2211 | } |
| 2212 | if (crypt_stat->key_size == 0) |
| 2213 | crypt_stat->key_size = |
| 2214 | mount_crypt_stat->global_default_cipher_key_size; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2215 | if (auth_tok->session_key.encrypted_key_size == 0) |
| 2216 | auth_tok->session_key.encrypted_key_size = |
| 2217 | crypt_stat->key_size; |
| 2218 | if (crypt_stat->key_size == 24 |
| 2219 | && strcmp("aes", crypt_stat->cipher) == 0) { |
| 2220 | memset((crypt_stat->key + 24), 0, 8); |
| 2221 | auth_tok->session_key.encrypted_key_size = 32; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2222 | } else |
| 2223 | auth_tok->session_key.encrypted_key_size = crypt_stat->key_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2224 | key_rec->enc_key_size = |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2225 | auth_tok->session_key.encrypted_key_size; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2226 | encrypted_session_key_valid = 0; |
| 2227 | for (i = 0; i < auth_tok->session_key.encrypted_key_size; i++) |
| 2228 | encrypted_session_key_valid |= |
| 2229 | auth_tok->session_key.encrypted_key[i]; |
| 2230 | if (encrypted_session_key_valid) { |
| 2231 | ecryptfs_printk(KERN_DEBUG, "encrypted_session_key_valid != 0; " |
| 2232 | "using auth_tok->session_key.encrypted_key, " |
Tyler Hicks | f24b388 | 2010-11-15 17:36:38 -0600 | [diff] [blame] | 2233 | "where key_rec->enc_key_size = [%zd]\n", |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2234 | key_rec->enc_key_size); |
| 2235 | memcpy(key_rec->enc_key, |
| 2236 | auth_tok->session_key.encrypted_key, |
| 2237 | key_rec->enc_key_size); |
| 2238 | goto encrypted_session_key_set; |
| 2239 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2240 | if (auth_tok->token.password.flags & |
| 2241 | ECRYPTFS_SESSION_KEY_ENCRYPTION_KEY_SET) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2242 | ecryptfs_printk(KERN_DEBUG, "Using previously generated " |
| 2243 | "session key encryption key of size [%d]\n", |
| 2244 | auth_tok->token.password. |
| 2245 | session_key_encryption_key_bytes); |
| 2246 | memcpy(session_key_encryption_key, |
| 2247 | auth_tok->token.password.session_key_encryption_key, |
| 2248 | crypt_stat->key_size); |
| 2249 | ecryptfs_printk(KERN_DEBUG, |
Jean Delvare | df2e301 | 2011-07-16 18:10:35 +0200 | [diff] [blame] | 2250 | "Cached session key encryption key:\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2251 | if (ecryptfs_verbosity > 0) |
| 2252 | ecryptfs_dump_hex(session_key_encryption_key, 16); |
| 2253 | } |
| 2254 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 2255 | ecryptfs_printk(KERN_DEBUG, "Session key encryption key:\n"); |
| 2256 | ecryptfs_dump_hex(session_key_encryption_key, 16); |
| 2257 | } |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 2258 | rc = virt_to_scatterlist(crypt_stat->key, key_rec->enc_key_size, |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 2259 | src_sg, 2); |
| 2260 | if (rc < 1 || rc > 2) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2261 | ecryptfs_printk(KERN_ERR, "Error generating scatterlist " |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2262 | "for crypt_stat session key; expected rc = 1; " |
Tyler Hicks | f24b388 | 2010-11-15 17:36:38 -0600 | [diff] [blame] | 2263 | "got rc = [%d]. key_rec->enc_key_size = [%zd]\n", |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2264 | rc, key_rec->enc_key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2265 | rc = -ENOMEM; |
| 2266 | goto out; |
| 2267 | } |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 2268 | rc = virt_to_scatterlist(key_rec->enc_key, key_rec->enc_key_size, |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 2269 | dst_sg, 2); |
| 2270 | if (rc < 1 || rc > 2) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2271 | ecryptfs_printk(KERN_ERR, "Error generating scatterlist " |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2272 | "for crypt_stat encrypted session key; " |
| 2273 | "expected rc = 1; got rc = [%d]. " |
Tyler Hicks | f24b388 | 2010-11-15 17:36:38 -0600 | [diff] [blame] | 2274 | "key_rec->enc_key_size = [%zd]\n", rc, |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2275 | key_rec->enc_key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2276 | rc = -ENOMEM; |
| 2277 | goto out; |
| 2278 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2279 | mutex_lock(tfm_mutex); |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 2280 | rc = crypto_skcipher_setkey(tfm, session_key_encryption_key, |
| 2281 | crypt_stat->key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2282 | if (rc < 0) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2283 | mutex_unlock(tfm_mutex); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2284 | ecryptfs_printk(KERN_ERR, "Error setting key for crypto " |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 2285 | "context; rc = [%d]\n", rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2286 | goto out; |
| 2287 | } |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 2288 | |
| 2289 | req = skcipher_request_alloc(tfm, GFP_KERNEL); |
| 2290 | if (!req) { |
| 2291 | mutex_unlock(tfm_mutex); |
| 2292 | ecryptfs_printk(KERN_ERR, "Out of kernel memory whilst " |
| 2293 | "attempting to skcipher_request_alloc for " |
| 2294 | "%s\n", crypto_skcipher_driver_name(tfm)); |
| 2295 | rc = -ENOMEM; |
| 2296 | goto out; |
| 2297 | } |
| 2298 | |
| 2299 | skcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, |
| 2300 | NULL, NULL); |
| 2301 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2302 | rc = 0; |
Tyler Hicks | f24b388 | 2010-11-15 17:36:38 -0600 | [diff] [blame] | 2303 | ecryptfs_printk(KERN_DEBUG, "Encrypting [%zd] bytes of the key\n", |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2304 | crypt_stat->key_size); |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 2305 | skcipher_request_set_crypt(req, src_sg, dst_sg, |
| 2306 | (*key_rec).enc_key_size, NULL); |
| 2307 | rc = crypto_skcipher_encrypt(req); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2308 | mutex_unlock(tfm_mutex); |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 2309 | skcipher_request_free(req); |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 2310 | if (rc) { |
| 2311 | printk(KERN_ERR "Error encrypting; rc = [%d]\n", rc); |
| 2312 | goto out; |
| 2313 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2314 | ecryptfs_printk(KERN_DEBUG, "This should be the encrypted key:\n"); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2315 | if (ecryptfs_verbosity > 0) { |
Tyler Hicks | f24b388 | 2010-11-15 17:36:38 -0600 | [diff] [blame] | 2316 | ecryptfs_printk(KERN_DEBUG, "EFEK of size [%zd]:\n", |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2317 | key_rec->enc_key_size); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2318 | ecryptfs_dump_hex(key_rec->enc_key, |
| 2319 | key_rec->enc_key_size); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2320 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2321 | encrypted_session_key_set: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2322 | /* This format is inspired by OpenPGP; see RFC 2440 |
| 2323 | * packet tag 3 */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2324 | max_packet_size = (1 /* Tag 3 identifier */ |
| 2325 | + 3 /* Max Tag 3 packet size */ |
| 2326 | + 1 /* Version */ |
| 2327 | + 1 /* Cipher code */ |
| 2328 | + 1 /* S2K specifier */ |
| 2329 | + 1 /* Hash identifier */ |
| 2330 | + ECRYPTFS_SALT_SIZE /* Salt */ |
| 2331 | + 1 /* Hash iterations */ |
| 2332 | + key_rec->enc_key_size); /* Encrypted key size */ |
| 2333 | if (max_packet_size > (*remaining_bytes)) { |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 2334 | printk(KERN_ERR "Packet too large; need up to [%td] bytes, but " |
| 2335 | "there are only [%td] available\n", max_packet_size, |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2336 | (*remaining_bytes)); |
| 2337 | rc = -EINVAL; |
| 2338 | goto out; |
| 2339 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2340 | dest[(*packet_size)++] = ECRYPTFS_TAG_3_PACKET_TYPE; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2341 | /* Chop off the Tag 3 identifier(1) and Tag 3 packet size(3) |
| 2342 | * to get the number of octets in the actual Tag 3 packet */ |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 2343 | rc = ecryptfs_write_packet_length(&dest[(*packet_size)], |
| 2344 | (max_packet_size - 4), |
| 2345 | &packet_size_length); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2346 | if (rc) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2347 | printk(KERN_ERR "Error generating tag 3 packet header; cannot " |
| 2348 | "generate packet length. rc = [%d]\n", rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2349 | goto out; |
| 2350 | } |
| 2351 | (*packet_size) += packet_size_length; |
| 2352 | dest[(*packet_size)++] = 0x04; /* version 4 */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2353 | /* TODO: Break from RFC2440 so that arbitrary ciphers can be |
| 2354 | * specified with strings */ |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 2355 | cipher_code = ecryptfs_code_for_cipher_string(crypt_stat->cipher, |
| 2356 | crypt_stat->key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2357 | if (cipher_code == 0) { |
| 2358 | ecryptfs_printk(KERN_WARNING, "Unable to generate code for " |
| 2359 | "cipher [%s]\n", crypt_stat->cipher); |
| 2360 | rc = -EINVAL; |
| 2361 | goto out; |
| 2362 | } |
| 2363 | dest[(*packet_size)++] = cipher_code; |
| 2364 | dest[(*packet_size)++] = 0x03; /* S2K */ |
| 2365 | dest[(*packet_size)++] = 0x01; /* MD5 (TODO: parameterize) */ |
| 2366 | memcpy(&dest[(*packet_size)], auth_tok->token.password.salt, |
| 2367 | ECRYPTFS_SALT_SIZE); |
| 2368 | (*packet_size) += ECRYPTFS_SALT_SIZE; /* salt */ |
| 2369 | dest[(*packet_size)++] = 0x60; /* hash iterations (65536) */ |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2370 | memcpy(&dest[(*packet_size)], key_rec->enc_key, |
| 2371 | key_rec->enc_key_size); |
| 2372 | (*packet_size) += key_rec->enc_key_size; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2373 | out: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2374 | if (rc) |
| 2375 | (*packet_size) = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2376 | else |
| 2377 | (*remaining_bytes) -= (*packet_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2378 | return rc; |
| 2379 | } |
| 2380 | |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2381 | struct kmem_cache *ecryptfs_key_record_cache; |
| 2382 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2383 | /** |
| 2384 | * ecryptfs_generate_key_packet_set |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 2385 | * @dest_base: Virtual address from which to write the key record set |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2386 | * @crypt_stat: The cryptographic context from which the |
| 2387 | * authentication tokens will be retrieved |
| 2388 | * @ecryptfs_dentry: The dentry, used to retrieve the mount crypt stat |
| 2389 | * for the global parameters |
| 2390 | * @len: The amount written |
| 2391 | * @max: The maximum amount of data allowed to be written |
| 2392 | * |
| 2393 | * Generates a key packet set and writes it to the virtual address |
| 2394 | * passed in. |
| 2395 | * |
| 2396 | * Returns zero on success; non-zero on error. |
| 2397 | */ |
| 2398 | int |
| 2399 | ecryptfs_generate_key_packet_set(char *dest_base, |
| 2400 | struct ecryptfs_crypt_stat *crypt_stat, |
| 2401 | struct dentry *ecryptfs_dentry, size_t *len, |
| 2402 | size_t max) |
| 2403 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2404 | struct ecryptfs_auth_tok *auth_tok; |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 2405 | struct key *auth_tok_key = NULL; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2406 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat = |
| 2407 | &ecryptfs_superblock_to_private( |
| 2408 | ecryptfs_dentry->d_sb)->mount_crypt_stat; |
| 2409 | size_t written; |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2410 | struct ecryptfs_key_record *key_rec; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2411 | struct ecryptfs_key_sig *key_sig; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2412 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2413 | |
| 2414 | (*len) = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2415 | mutex_lock(&crypt_stat->keysig_list_mutex); |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2416 | key_rec = kmem_cache_alloc(ecryptfs_key_record_cache, GFP_KERNEL); |
| 2417 | if (!key_rec) { |
| 2418 | rc = -ENOMEM; |
| 2419 | goto out; |
| 2420 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2421 | list_for_each_entry(key_sig, &crypt_stat->keysig_list, |
| 2422 | crypt_stat_list) { |
| 2423 | memset(key_rec, 0, sizeof(*key_rec)); |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 2424 | rc = ecryptfs_find_global_auth_tok_for_sig(&auth_tok_key, |
| 2425 | &auth_tok, |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2426 | mount_crypt_stat, |
| 2427 | key_sig->keysig); |
| 2428 | if (rc) { |
Roberto Sassu | 0e1fc5e | 2011-03-21 16:00:53 +0100 | [diff] [blame] | 2429 | printk(KERN_WARNING "Unable to retrieve auth tok with " |
| 2430 | "sig = [%s]\n", key_sig->keysig); |
| 2431 | rc = process_find_global_auth_tok_for_sig_err(rc); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2432 | goto out_free; |
| 2433 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2434 | if (auth_tok->token_type == ECRYPTFS_PASSWORD) { |
| 2435 | rc = write_tag_3_packet((dest_base + (*len)), |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2436 | &max, auth_tok, |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2437 | crypt_stat, key_rec, |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2438 | &written); |
Tyler Hicks | b2987a5 | 2011-07-26 19:47:08 -0500 | [diff] [blame] | 2439 | up_write(&(auth_tok_key->sem)); |
| 2440 | key_put(auth_tok_key); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2441 | if (rc) { |
| 2442 | ecryptfs_printk(KERN_WARNING, "Error " |
| 2443 | "writing tag 3 packet\n"); |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2444 | goto out_free; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2445 | } |
| 2446 | (*len) += written; |
| 2447 | /* Write auth tok signature packet */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2448 | rc = write_tag_11_packet((dest_base + (*len)), &max, |
| 2449 | key_rec->sig, |
| 2450 | ECRYPTFS_SIG_SIZE, &written); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2451 | if (rc) { |
| 2452 | ecryptfs_printk(KERN_ERR, "Error writing " |
| 2453 | "auth tok signature packet\n"); |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2454 | goto out_free; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2455 | } |
| 2456 | (*len) += written; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2457 | } else if (auth_tok->token_type == ECRYPTFS_PRIVATE_KEY) { |
Tyler Hicks | b2987a5 | 2011-07-26 19:47:08 -0500 | [diff] [blame] | 2458 | rc = write_tag_1_packet(dest_base + (*len), &max, |
| 2459 | auth_tok_key, auth_tok, |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2460 | crypt_stat, key_rec, &written); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2461 | if (rc) { |
| 2462 | ecryptfs_printk(KERN_WARNING, "Error " |
| 2463 | "writing tag 1 packet\n"); |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2464 | goto out_free; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2465 | } |
| 2466 | (*len) += written; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2467 | } else { |
Tyler Hicks | b2987a5 | 2011-07-26 19:47:08 -0500 | [diff] [blame] | 2468 | up_write(&(auth_tok_key->sem)); |
| 2469 | key_put(auth_tok_key); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2470 | ecryptfs_printk(KERN_WARNING, "Unsupported " |
| 2471 | "authentication token type\n"); |
| 2472 | rc = -EINVAL; |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2473 | goto out_free; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2474 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2475 | } |
| 2476 | if (likely(max > 0)) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2477 | dest_base[(*len)] = 0x00; |
| 2478 | } else { |
| 2479 | ecryptfs_printk(KERN_ERR, "Error writing boundary byte\n"); |
| 2480 | rc = -EIO; |
| 2481 | } |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2482 | out_free: |
| 2483 | kmem_cache_free(ecryptfs_key_record_cache, key_rec); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2484 | out: |
| 2485 | if (rc) |
| 2486 | (*len) = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2487 | mutex_unlock(&crypt_stat->keysig_list_mutex); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2488 | return rc; |
| 2489 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2490 | |
| 2491 | struct kmem_cache *ecryptfs_key_sig_cache; |
| 2492 | |
| 2493 | int ecryptfs_add_keysig(struct ecryptfs_crypt_stat *crypt_stat, char *sig) |
| 2494 | { |
| 2495 | struct ecryptfs_key_sig *new_key_sig; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2496 | |
| 2497 | new_key_sig = kmem_cache_alloc(ecryptfs_key_sig_cache, GFP_KERNEL); |
Markus Elfring | 1a0bba4 | 2017-08-19 17:37:30 +0200 | [diff] [blame] | 2498 | if (!new_key_sig) |
Roland Dreier | aa06117 | 2009-07-01 15:48:18 -0700 | [diff] [blame] | 2499 | return -ENOMEM; |
Markus Elfring | 1a0bba4 | 2017-08-19 17:37:30 +0200 | [diff] [blame] | 2500 | |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2501 | memcpy(new_key_sig->keysig, sig, ECRYPTFS_SIG_SIZE_HEX); |
Roberto Sassu | 7762e23 | 2011-03-21 16:00:52 +0100 | [diff] [blame] | 2502 | new_key_sig->keysig[ECRYPTFS_SIG_SIZE_HEX] = '\0'; |
Roland Dreier | aa06117 | 2009-07-01 15:48:18 -0700 | [diff] [blame] | 2503 | /* Caller must hold keysig_list_mutex */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2504 | list_add(&new_key_sig->crypt_stat_list, &crypt_stat->keysig_list); |
Roland Dreier | aa06117 | 2009-07-01 15:48:18 -0700 | [diff] [blame] | 2505 | |
| 2506 | return 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2507 | } |
| 2508 | |
| 2509 | struct kmem_cache *ecryptfs_global_auth_tok_cache; |
| 2510 | |
| 2511 | int |
| 2512 | ecryptfs_add_global_auth_tok(struct ecryptfs_mount_crypt_stat *mount_crypt_stat, |
Tyler Hicks | 84814d6 | 2009-03-13 13:51:59 -0700 | [diff] [blame] | 2513 | char *sig, u32 global_auth_tok_flags) |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2514 | { |
| 2515 | struct ecryptfs_global_auth_tok *new_auth_tok; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2516 | |
Eric Sandeen | 459e216 | 2007-12-17 16:19:52 -0800 | [diff] [blame] | 2517 | new_auth_tok = kmem_cache_zalloc(ecryptfs_global_auth_tok_cache, |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2518 | GFP_KERNEL); |
Markus Elfring | a463ce5 | 2017-08-19 17:51:53 +0200 | [diff] [blame] | 2519 | if (!new_auth_tok) |
| 2520 | return -ENOMEM; |
| 2521 | |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2522 | memcpy(new_auth_tok->sig, sig, ECRYPTFS_SIG_SIZE_HEX); |
Tyler Hicks | 84814d6 | 2009-03-13 13:51:59 -0700 | [diff] [blame] | 2523 | new_auth_tok->flags = global_auth_tok_flags; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2524 | new_auth_tok->sig[ECRYPTFS_SIG_SIZE_HEX] = '\0'; |
| 2525 | mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex); |
| 2526 | list_add(&new_auth_tok->mount_crypt_stat_list, |
| 2527 | &mount_crypt_stat->global_auth_tok_list); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2528 | mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex); |
Markus Elfring | a463ce5 | 2017-08-19 17:51:53 +0200 | [diff] [blame] | 2529 | return 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2530 | } |
| 2531 | |