Thomas Gleixner | 1a59d1b8 | 2019-05-27 08:55:05 +0200 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2 | /** |
| 3 | * eCryptfs: Linux filesystem encryption layer |
| 4 | * |
| 5 | * Copyright (C) 1997-2004 Erez Zadok |
| 6 | * Copyright (C) 2001-2004 Stony Brook University |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 7 | * Copyright (C) 2004-2007 International Business Machines Corp. |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 8 | * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com> |
| 9 | * Michael C. Thompson <mcthomps@us.ibm.com> |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 10 | */ |
| 11 | |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 12 | #include <crypto/hash.h> |
| 13 | #include <crypto/skcipher.h> |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 14 | #include <linux/fs.h> |
| 15 | #include <linux/mount.h> |
| 16 | #include <linux/pagemap.h> |
| 17 | #include <linux/random.h> |
| 18 | #include <linux/compiler.h> |
| 19 | #include <linux/key.h> |
| 20 | #include <linux/namei.h> |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 21 | #include <linux/file.h> |
| 22 | #include <linux/scatterlist.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 23 | #include <linux/slab.h> |
Harvey Harrison | 29335c6 | 2008-07-23 21:30:06 -0700 | [diff] [blame] | 24 | #include <asm/unaligned.h> |
Jérémy Lefaure | 02f9876 | 2017-10-01 15:30:46 -0400 | [diff] [blame] | 25 | #include <linux/kernel.h> |
Robbie Ko | d43388d | 2018-08-21 16:17:40 +0800 | [diff] [blame] | 26 | #include <linux/xattr.h> |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 27 | #include "ecryptfs_kernel.h" |
| 28 | |
Tyler Hicks | 00a6994 | 2013-04-05 23:26:22 -0700 | [diff] [blame] | 29 | #define DECRYPT 0 |
| 30 | #define ENCRYPT 1 |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 31 | |
| 32 | /** |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 33 | * ecryptfs_from_hex |
| 34 | * @dst: Buffer to take the bytes from src hex; must be at least of |
| 35 | * size (src_size / 2) |
Wei Yuan | 5f9f2c2 | 2016-02-17 14:50:10 +0800 | [diff] [blame] | 36 | * @src: Buffer to be converted from a hex string representation to raw value |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 37 | * @dst_size: size of dst buffer, or number of hex characters pairs to convert |
| 38 | */ |
| 39 | void ecryptfs_from_hex(char *dst, char *src, int dst_size) |
| 40 | { |
| 41 | int x; |
| 42 | char tmp[3] = { 0, }; |
| 43 | |
| 44 | for (x = 0; x < dst_size; x++) { |
| 45 | tmp[0] = src[x * 2]; |
| 46 | tmp[1] = src[x * 2 + 1]; |
| 47 | dst[x] = (unsigned char)simple_strtol(tmp, NULL, 16); |
| 48 | } |
| 49 | } |
| 50 | |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 51 | static int ecryptfs_hash_digest(struct crypto_shash *tfm, |
| 52 | char *src, int len, char *dst) |
| 53 | { |
| 54 | SHASH_DESC_ON_STACK(desc, tfm); |
| 55 | int err; |
| 56 | |
| 57 | desc->tfm = tfm; |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 58 | err = crypto_shash_digest(desc, src, len, dst); |
| 59 | shash_desc_zero(desc); |
| 60 | return err; |
| 61 | } |
| 62 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 63 | /** |
| 64 | * ecryptfs_calculate_md5 - calculates the md5 of @src |
| 65 | * @dst: Pointer to 16 bytes of allocated memory |
| 66 | * @crypt_stat: Pointer to crypt_stat struct for the current inode |
| 67 | * @src: Data to be md5'd |
| 68 | * @len: Length of @src |
| 69 | * |
| 70 | * Uses the allocated crypto context that crypt_stat references to |
| 71 | * generate the MD5 sum of the contents of src. |
| 72 | */ |
| 73 | static int ecryptfs_calculate_md5(char *dst, |
| 74 | struct ecryptfs_crypt_stat *crypt_stat, |
| 75 | char *src, int len) |
| 76 | { |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 77 | struct crypto_shash *tfm; |
Michael Halcrow | 565d9724 | 2006-10-30 22:07:17 -0800 | [diff] [blame] | 78 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 79 | |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 80 | tfm = crypt_stat->hash_tfm; |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 81 | rc = ecryptfs_hash_digest(tfm, src, len, dst); |
Michael Halcrow | 8a29f2b | 2007-11-05 14:51:04 -0800 | [diff] [blame] | 82 | if (rc) { |
| 83 | printk(KERN_ERR |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 84 | "%s: Error computing crypto hash; rc = [%d]\n", |
Harvey Harrison | 18d1dbf | 2008-04-29 00:59:48 -0700 | [diff] [blame] | 85 | __func__, rc); |
Michael Halcrow | 8a29f2b | 2007-11-05 14:51:04 -0800 | [diff] [blame] | 86 | goto out; |
| 87 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 88 | out: |
| 89 | return rc; |
| 90 | } |
| 91 | |
Michael Halcrow | cd9d67d | 2007-10-16 01:28:04 -0700 | [diff] [blame] | 92 | static int ecryptfs_crypto_api_algify_cipher_name(char **algified_name, |
| 93 | char *cipher_name, |
| 94 | char *chaining_modifier) |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 95 | { |
| 96 | int cipher_name_len = strlen(cipher_name); |
| 97 | int chaining_modifier_len = strlen(chaining_modifier); |
| 98 | int algified_name_len; |
| 99 | int rc; |
| 100 | |
| 101 | algified_name_len = (chaining_modifier_len + cipher_name_len + 3); |
| 102 | (*algified_name) = kmalloc(algified_name_len, GFP_KERNEL); |
Michael Halcrow | 7bd473f | 2006-11-02 22:06:56 -0800 | [diff] [blame] | 103 | if (!(*algified_name)) { |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 104 | rc = -ENOMEM; |
| 105 | goto out; |
| 106 | } |
| 107 | snprintf((*algified_name), algified_name_len, "%s(%s)", |
| 108 | chaining_modifier, cipher_name); |
| 109 | rc = 0; |
| 110 | out: |
| 111 | return rc; |
| 112 | } |
| 113 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 114 | /** |
| 115 | * ecryptfs_derive_iv |
| 116 | * @iv: destination for the derived iv vale |
| 117 | * @crypt_stat: Pointer to crypt_stat struct for the current inode |
Michael Halcrow | d6a13c1 | 2007-10-16 01:28:12 -0700 | [diff] [blame] | 118 | * @offset: Offset of the extent whose IV we are to derive |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 119 | * |
| 120 | * Generate the initialization vector from the given root IV and page |
| 121 | * offset. |
| 122 | * |
| 123 | * Returns zero on success; non-zero on error. |
| 124 | */ |
Michael Halcrow | a34f60f | 2009-01-06 14:41:58 -0800 | [diff] [blame] | 125 | int ecryptfs_derive_iv(char *iv, struct ecryptfs_crypt_stat *crypt_stat, |
| 126 | loff_t offset) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 127 | { |
| 128 | int rc = 0; |
| 129 | char dst[MD5_DIGEST_SIZE]; |
| 130 | char src[ECRYPTFS_MAX_IV_BYTES + 16]; |
| 131 | |
| 132 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 133 | ecryptfs_printk(KERN_DEBUG, "root iv:\n"); |
| 134 | ecryptfs_dump_hex(crypt_stat->root_iv, crypt_stat->iv_bytes); |
| 135 | } |
| 136 | /* TODO: It is probably secure to just cast the least |
| 137 | * significant bits of the root IV into an unsigned long and |
| 138 | * add the offset to that rather than go through all this |
| 139 | * hashing business. -Halcrow */ |
| 140 | memcpy(src, crypt_stat->root_iv, crypt_stat->iv_bytes); |
| 141 | memset((src + crypt_stat->iv_bytes), 0, 16); |
Michael Halcrow | d6a13c1 | 2007-10-16 01:28:12 -0700 | [diff] [blame] | 142 | snprintf((src + crypt_stat->iv_bytes), 16, "%lld", offset); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 143 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 144 | ecryptfs_printk(KERN_DEBUG, "source:\n"); |
| 145 | ecryptfs_dump_hex(src, (crypt_stat->iv_bytes + 16)); |
| 146 | } |
| 147 | rc = ecryptfs_calculate_md5(dst, crypt_stat, src, |
| 148 | (crypt_stat->iv_bytes + 16)); |
| 149 | if (rc) { |
| 150 | ecryptfs_printk(KERN_WARNING, "Error attempting to compute " |
| 151 | "MD5 while generating IV for a page\n"); |
| 152 | goto out; |
| 153 | } |
| 154 | memcpy(iv, dst, crypt_stat->iv_bytes); |
| 155 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 156 | ecryptfs_printk(KERN_DEBUG, "derived iv:\n"); |
| 157 | ecryptfs_dump_hex(iv, crypt_stat->iv_bytes); |
| 158 | } |
| 159 | out: |
| 160 | return rc; |
| 161 | } |
| 162 | |
| 163 | /** |
| 164 | * ecryptfs_init_crypt_stat |
| 165 | * @crypt_stat: Pointer to the crypt_stat struct to initialize. |
| 166 | * |
| 167 | * Initialize the crypt_stat structure. |
| 168 | */ |
Herbert Xu | e81f334 | 2016-04-16 15:01:09 +0800 | [diff] [blame] | 169 | int ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 170 | { |
Herbert Xu | e81f334 | 2016-04-16 15:01:09 +0800 | [diff] [blame] | 171 | struct crypto_shash *tfm; |
| 172 | int rc; |
| 173 | |
| 174 | tfm = crypto_alloc_shash(ECRYPTFS_DEFAULT_HASH, 0, 0); |
| 175 | if (IS_ERR(tfm)) { |
| 176 | rc = PTR_ERR(tfm); |
| 177 | ecryptfs_printk(KERN_ERR, "Error attempting to " |
| 178 | "allocate crypto context; rc = [%d]\n", |
| 179 | rc); |
| 180 | return rc; |
| 181 | } |
| 182 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 183 | memset((void *)crypt_stat, 0, sizeof(struct ecryptfs_crypt_stat)); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 184 | INIT_LIST_HEAD(&crypt_stat->keysig_list); |
| 185 | mutex_init(&crypt_stat->keysig_list_mutex); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 186 | mutex_init(&crypt_stat->cs_mutex); |
| 187 | mutex_init(&crypt_stat->cs_tfm_mutex); |
Herbert Xu | e81f334 | 2016-04-16 15:01:09 +0800 | [diff] [blame] | 188 | crypt_stat->hash_tfm = tfm; |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 189 | crypt_stat->flags |= ECRYPTFS_STRUCT_INITIALIZED; |
Herbert Xu | e81f334 | 2016-04-16 15:01:09 +0800 | [diff] [blame] | 190 | |
| 191 | return 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 192 | } |
| 193 | |
| 194 | /** |
Michael Halcrow | fcd1283 | 2007-10-16 01:28:01 -0700 | [diff] [blame] | 195 | * ecryptfs_destroy_crypt_stat |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 196 | * @crypt_stat: Pointer to the crypt_stat struct to initialize. |
| 197 | * |
| 198 | * Releases all memory associated with a crypt_stat struct. |
| 199 | */ |
Michael Halcrow | fcd1283 | 2007-10-16 01:28:01 -0700 | [diff] [blame] | 200 | void ecryptfs_destroy_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 201 | { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 202 | struct ecryptfs_key_sig *key_sig, *key_sig_tmp; |
| 203 | |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 204 | crypto_free_skcipher(crypt_stat->tfm); |
| 205 | crypto_free_shash(crypt_stat->hash_tfm); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 206 | list_for_each_entry_safe(key_sig, key_sig_tmp, |
| 207 | &crypt_stat->keysig_list, crypt_stat_list) { |
| 208 | list_del(&key_sig->crypt_stat_list); |
| 209 | kmem_cache_free(ecryptfs_key_sig_cache, key_sig); |
| 210 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 211 | memset(crypt_stat, 0, sizeof(struct ecryptfs_crypt_stat)); |
| 212 | } |
| 213 | |
Michael Halcrow | fcd1283 | 2007-10-16 01:28:01 -0700 | [diff] [blame] | 214 | void ecryptfs_destroy_mount_crypt_stat( |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 215 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat) |
| 216 | { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 217 | struct ecryptfs_global_auth_tok *auth_tok, *auth_tok_tmp; |
| 218 | |
| 219 | if (!(mount_crypt_stat->flags & ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED)) |
| 220 | return; |
| 221 | mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex); |
| 222 | list_for_each_entry_safe(auth_tok, auth_tok_tmp, |
| 223 | &mount_crypt_stat->global_auth_tok_list, |
| 224 | mount_crypt_stat_list) { |
| 225 | list_del(&auth_tok->mount_crypt_stat_list); |
Markus Elfring | 0dad87f | 2015-06-26 18:18:54 +0200 | [diff] [blame] | 226 | if (!(auth_tok->flags & ECRYPTFS_AUTH_TOK_INVALID)) |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 227 | key_put(auth_tok->global_auth_tok_key); |
| 228 | kmem_cache_free(ecryptfs_global_auth_tok_cache, auth_tok); |
| 229 | } |
| 230 | mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 231 | memset(mount_crypt_stat, 0, sizeof(struct ecryptfs_mount_crypt_stat)); |
| 232 | } |
| 233 | |
| 234 | /** |
| 235 | * virt_to_scatterlist |
| 236 | * @addr: Virtual address |
| 237 | * @size: Size of data; should be an even multiple of the block size |
| 238 | * @sg: Pointer to scatterlist array; set to NULL to obtain only |
| 239 | * the number of scatterlist structs required in array |
| 240 | * @sg_size: Max array size |
| 241 | * |
| 242 | * Fills in a scatterlist array with page references for a passed |
| 243 | * virtual address. |
| 244 | * |
| 245 | * Returns the number of scatterlist structs in array used |
| 246 | */ |
| 247 | int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg, |
| 248 | int sg_size) |
| 249 | { |
| 250 | int i = 0; |
| 251 | struct page *pg; |
| 252 | int offset; |
| 253 | int remainder_of_page; |
| 254 | |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 255 | sg_init_table(sg, sg_size); |
| 256 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 257 | while (size > 0 && i < sg_size) { |
| 258 | pg = virt_to_page(addr); |
| 259 | offset = offset_in_page(addr); |
Dan Carpenter | a07c48a | 2013-01-26 10:48:42 +0300 | [diff] [blame] | 260 | sg_set_page(&sg[i], pg, 0, offset); |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 261 | remainder_of_page = PAGE_SIZE - offset; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 262 | if (size >= remainder_of_page) { |
Dan Carpenter | a07c48a | 2013-01-26 10:48:42 +0300 | [diff] [blame] | 263 | sg[i].length = remainder_of_page; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 264 | addr += remainder_of_page; |
| 265 | size -= remainder_of_page; |
| 266 | } else { |
Dan Carpenter | a07c48a | 2013-01-26 10:48:42 +0300 | [diff] [blame] | 267 | sg[i].length = size; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 268 | addr += size; |
| 269 | size = 0; |
| 270 | } |
| 271 | i++; |
| 272 | } |
| 273 | if (size > 0) |
| 274 | return -ENOMEM; |
| 275 | return i; |
| 276 | } |
| 277 | |
Tyler Hicks | 4dfea4f | 2013-05-09 16:55:07 -0700 | [diff] [blame] | 278 | struct extent_crypt_result { |
| 279 | struct completion completion; |
| 280 | int rc; |
| 281 | }; |
| 282 | |
| 283 | static void extent_crypt_complete(struct crypto_async_request *req, int rc) |
| 284 | { |
| 285 | struct extent_crypt_result *ecr = req->data; |
| 286 | |
| 287 | if (rc == -EINPROGRESS) |
| 288 | return; |
| 289 | |
| 290 | ecr->rc = rc; |
| 291 | complete(&ecr->completion); |
| 292 | } |
| 293 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 294 | /** |
Tyler Hicks | 00a6994 | 2013-04-05 23:26:22 -0700 | [diff] [blame] | 295 | * crypt_scatterlist |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 296 | * @crypt_stat: Pointer to the crypt_stat struct to initialize. |
Tyler Hicks | 0df5ed6 | 2013-05-23 12:08:40 -0700 | [diff] [blame] | 297 | * @dst_sg: Destination of the data after performing the crypto operation |
Tyler Hicks | 00a6994 | 2013-04-05 23:26:22 -0700 | [diff] [blame] | 298 | * @src_sg: Data to be encrypted or decrypted |
| 299 | * @size: Length of data |
| 300 | * @iv: IV to use |
| 301 | * @op: ENCRYPT or DECRYPT to indicate the desired operation |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 302 | * |
Tyler Hicks | 00a6994 | 2013-04-05 23:26:22 -0700 | [diff] [blame] | 303 | * Returns the number of bytes encrypted or decrypted; negative value on error |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 304 | */ |
Tyler Hicks | 00a6994 | 2013-04-05 23:26:22 -0700 | [diff] [blame] | 305 | static int crypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat, |
Tyler Hicks | 0df5ed6 | 2013-05-23 12:08:40 -0700 | [diff] [blame] | 306 | struct scatterlist *dst_sg, |
Tyler Hicks | 00a6994 | 2013-04-05 23:26:22 -0700 | [diff] [blame] | 307 | struct scatterlist *src_sg, int size, |
| 308 | unsigned char *iv, int op) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 309 | { |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 310 | struct skcipher_request *req = NULL; |
Tyler Hicks | 4dfea4f | 2013-05-09 16:55:07 -0700 | [diff] [blame] | 311 | struct extent_crypt_result ecr; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 312 | int rc = 0; |
| 313 | |
Aditya Pakki | 2c2a755 | 2020-02-14 12:21:01 -0600 | [diff] [blame] | 314 | if (!crypt_stat || !crypt_stat->tfm |
| 315 | || !(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED)) |
| 316 | return -EINVAL; |
| 317 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 318 | if (unlikely(ecryptfs_verbosity > 0)) { |
Tyler Hicks | f24b388 | 2010-11-15 17:36:38 -0600 | [diff] [blame] | 319 | ecryptfs_printk(KERN_DEBUG, "Key size [%zd]; key:\n", |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 320 | crypt_stat->key_size); |
| 321 | ecryptfs_dump_hex(crypt_stat->key, |
| 322 | crypt_stat->key_size); |
| 323 | } |
Tyler Hicks | 4dfea4f | 2013-05-09 16:55:07 -0700 | [diff] [blame] | 324 | |
| 325 | init_completion(&ecr.completion); |
| 326 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 327 | mutex_lock(&crypt_stat->cs_tfm_mutex); |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 328 | req = skcipher_request_alloc(crypt_stat->tfm, GFP_NOFS); |
Tyler Hicks | 4dfea4f | 2013-05-09 16:55:07 -0700 | [diff] [blame] | 329 | if (!req) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 330 | mutex_unlock(&crypt_stat->cs_tfm_mutex); |
Tyler Hicks | 4dfea4f | 2013-05-09 16:55:07 -0700 | [diff] [blame] | 331 | rc = -ENOMEM; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 332 | goto out; |
| 333 | } |
Tyler Hicks | 4dfea4f | 2013-05-09 16:55:07 -0700 | [diff] [blame] | 334 | |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 335 | skcipher_request_set_callback(req, |
Tyler Hicks | 4dfea4f | 2013-05-09 16:55:07 -0700 | [diff] [blame] | 336 | CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP, |
| 337 | extent_crypt_complete, &ecr); |
| 338 | /* Consider doing this once, when the file is opened */ |
| 339 | if (!(crypt_stat->flags & ECRYPTFS_KEY_SET)) { |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 340 | rc = crypto_skcipher_setkey(crypt_stat->tfm, crypt_stat->key, |
| 341 | crypt_stat->key_size); |
Tyler Hicks | 4dfea4f | 2013-05-09 16:55:07 -0700 | [diff] [blame] | 342 | if (rc) { |
| 343 | ecryptfs_printk(KERN_ERR, |
| 344 | "Error setting key; rc = [%d]\n", |
| 345 | rc); |
| 346 | mutex_unlock(&crypt_stat->cs_tfm_mutex); |
| 347 | rc = -EINVAL; |
| 348 | goto out; |
| 349 | } |
| 350 | crypt_stat->flags |= ECRYPTFS_KEY_SET; |
| 351 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 352 | mutex_unlock(&crypt_stat->cs_tfm_mutex); |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 353 | skcipher_request_set_crypt(req, src_sg, dst_sg, size, iv); |
| 354 | rc = op == ENCRYPT ? crypto_skcipher_encrypt(req) : |
| 355 | crypto_skcipher_decrypt(req); |
Tyler Hicks | 4dfea4f | 2013-05-09 16:55:07 -0700 | [diff] [blame] | 356 | if (rc == -EINPROGRESS || rc == -EBUSY) { |
| 357 | struct extent_crypt_result *ecr = req->base.data; |
| 358 | |
| 359 | wait_for_completion(&ecr->completion); |
| 360 | rc = ecr->rc; |
Wolfram Sang | 16735d0 | 2013-11-14 14:32:02 -0800 | [diff] [blame] | 361 | reinit_completion(&ecr->completion); |
Tyler Hicks | 4dfea4f | 2013-05-09 16:55:07 -0700 | [diff] [blame] | 362 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 363 | out: |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 364 | skcipher_request_free(req); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 365 | return rc; |
| 366 | } |
| 367 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 368 | /** |
Tyler Hicks | 24d1526 | 2013-04-15 17:28:09 -0700 | [diff] [blame] | 369 | * lower_offset_for_page |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 370 | * |
| 371 | * Convert an eCryptfs page index into a lower byte offset |
| 372 | */ |
Tyler Hicks | 24d1526 | 2013-04-15 17:28:09 -0700 | [diff] [blame] | 373 | static loff_t lower_offset_for_page(struct ecryptfs_crypt_stat *crypt_stat, |
| 374 | struct page *page) |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 375 | { |
Tyler Hicks | 24d1526 | 2013-04-15 17:28:09 -0700 | [diff] [blame] | 376 | return ecryptfs_lower_header_size(crypt_stat) + |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 377 | ((loff_t)page->index << PAGE_SHIFT); |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 378 | } |
| 379 | |
| 380 | /** |
Tyler Hicks | d78de61 | 2013-04-06 00:08:48 -0700 | [diff] [blame] | 381 | * crypt_extent |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 382 | * @crypt_stat: crypt_stat containing cryptographic context for the |
| 383 | * encryption operation |
Tyler Hicks | 0df5ed6 | 2013-05-23 12:08:40 -0700 | [diff] [blame] | 384 | * @dst_page: The page to write the result into |
Tyler Hicks | d78de61 | 2013-04-06 00:08:48 -0700 | [diff] [blame] | 385 | * @src_page: The page to read from |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 386 | * @extent_offset: Page extent offset for use in generating IV |
Tyler Hicks | d78de61 | 2013-04-06 00:08:48 -0700 | [diff] [blame] | 387 | * @op: ENCRYPT or DECRYPT to indicate the desired operation |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 388 | * |
Tyler Hicks | d78de61 | 2013-04-06 00:08:48 -0700 | [diff] [blame] | 389 | * Encrypts or decrypts one extent of data. |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 390 | * |
| 391 | * Return zero on success; non-zero otherwise |
| 392 | */ |
Tyler Hicks | 0df5ed6 | 2013-05-23 12:08:40 -0700 | [diff] [blame] | 393 | static int crypt_extent(struct ecryptfs_crypt_stat *crypt_stat, |
| 394 | struct page *dst_page, |
Tyler Hicks | d78de61 | 2013-04-06 00:08:48 -0700 | [diff] [blame] | 395 | struct page *src_page, |
| 396 | unsigned long extent_offset, int op) |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 397 | { |
Tyler Hicks | d78de61 | 2013-04-06 00:08:48 -0700 | [diff] [blame] | 398 | pgoff_t page_index = op == ENCRYPT ? src_page->index : dst_page->index; |
Michael Halcrow | d6a13c1 | 2007-10-16 01:28:12 -0700 | [diff] [blame] | 399 | loff_t extent_base; |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 400 | char extent_iv[ECRYPTFS_MAX_IV_BYTES]; |
Tyler Hicks | 406c93d | 2013-04-15 17:49:31 -0700 | [diff] [blame] | 401 | struct scatterlist src_sg, dst_sg; |
| 402 | size_t extent_size = crypt_stat->extent_size; |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 403 | int rc; |
| 404 | |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 405 | extent_base = (((loff_t)page_index) * (PAGE_SIZE / extent_size)); |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 406 | rc = ecryptfs_derive_iv(extent_iv, crypt_stat, |
| 407 | (extent_base + extent_offset)); |
| 408 | if (rc) { |
Joe Perches | 888d57b | 2010-11-10 15:46:16 -0800 | [diff] [blame] | 409 | ecryptfs_printk(KERN_ERR, "Error attempting to derive IV for " |
| 410 | "extent [0x%.16llx]; rc = [%d]\n", |
| 411 | (unsigned long long)(extent_base + extent_offset), rc); |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 412 | goto out; |
| 413 | } |
Tyler Hicks | 406c93d | 2013-04-15 17:49:31 -0700 | [diff] [blame] | 414 | |
| 415 | sg_init_table(&src_sg, 1); |
| 416 | sg_init_table(&dst_sg, 1); |
| 417 | |
| 418 | sg_set_page(&src_sg, src_page, extent_size, |
| 419 | extent_offset * extent_size); |
| 420 | sg_set_page(&dst_sg, dst_page, extent_size, |
| 421 | extent_offset * extent_size); |
| 422 | |
| 423 | rc = crypt_scatterlist(crypt_stat, &dst_sg, &src_sg, extent_size, |
| 424 | extent_iv, op); |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 425 | if (rc < 0) { |
Tyler Hicks | d78de61 | 2013-04-06 00:08:48 -0700 | [diff] [blame] | 426 | printk(KERN_ERR "%s: Error attempting to crypt page with " |
| 427 | "page_index = [%ld], extent_offset = [%ld]; " |
| 428 | "rc = [%d]\n", __func__, page_index, extent_offset, rc); |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 429 | goto out; |
| 430 | } |
| 431 | rc = 0; |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 432 | out: |
| 433 | return rc; |
| 434 | } |
| 435 | |
| 436 | /** |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 437 | * ecryptfs_encrypt_page |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 438 | * @page: Page mapped from the eCryptfs inode for the file; contains |
| 439 | * decrypted content that needs to be encrypted (to a temporary |
| 440 | * page; not in place) and written out to the lower file |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 441 | * |
| 442 | * Encrypt an eCryptfs page. This is done on a per-extent basis. Note |
| 443 | * that eCryptfs pages may straddle the lower pages -- for instance, |
| 444 | * if the file was created on a machine with an 8K page size |
| 445 | * (resulting in an 8K header), and then the file is copied onto a |
| 446 | * host with a 32K page size, then when reading page 0 of the eCryptfs |
| 447 | * file, 24K of page 0 of the lower file will be read and decrypted, |
| 448 | * and then 8K of page 1 of the lower file will be read and decrypted. |
| 449 | * |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 450 | * Returns zero on success; negative on error |
| 451 | */ |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 452 | int ecryptfs_encrypt_page(struct page *page) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 453 | { |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 454 | struct inode *ecryptfs_inode; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 455 | struct ecryptfs_crypt_stat *crypt_stat; |
Eric Sandeen | 7fcba05 | 2008-07-28 15:46:39 -0700 | [diff] [blame] | 456 | char *enc_extent_virt; |
| 457 | struct page *enc_extent_page = NULL; |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 458 | loff_t extent_offset; |
Tyler Hicks | 0f89617 | 2013-04-15 16:16:24 -0700 | [diff] [blame] | 459 | loff_t lower_offset; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 460 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 461 | |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 462 | ecryptfs_inode = page->mapping->host; |
| 463 | crypt_stat = |
| 464 | &(ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat); |
Tyler Hicks | 13a791b | 2009-04-13 15:29:27 -0500 | [diff] [blame] | 465 | BUG_ON(!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)); |
Eric Sandeen | 7fcba05 | 2008-07-28 15:46:39 -0700 | [diff] [blame] | 466 | enc_extent_page = alloc_page(GFP_USER); |
| 467 | if (!enc_extent_page) { |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 468 | rc = -ENOMEM; |
| 469 | ecryptfs_printk(KERN_ERR, "Error allocating memory for " |
| 470 | "encrypted extent\n"); |
| 471 | goto out; |
| 472 | } |
Tyler Hicks | 0f89617 | 2013-04-15 16:16:24 -0700 | [diff] [blame] | 473 | |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 474 | for (extent_offset = 0; |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 475 | extent_offset < (PAGE_SIZE / crypt_stat->extent_size); |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 476 | extent_offset++) { |
Tyler Hicks | 0df5ed6 | 2013-05-23 12:08:40 -0700 | [diff] [blame] | 477 | rc = crypt_extent(crypt_stat, enc_extent_page, page, |
Tyler Hicks | d78de61 | 2013-04-06 00:08:48 -0700 | [diff] [blame] | 478 | extent_offset, ENCRYPT); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 479 | if (rc) { |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 480 | printk(KERN_ERR "%s: Error encrypting extent; " |
Harvey Harrison | 18d1dbf | 2008-04-29 00:59:48 -0700 | [diff] [blame] | 481 | "rc = [%d]\n", __func__, rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 482 | goto out; |
| 483 | } |
Tyler Hicks | 0f89617 | 2013-04-15 16:16:24 -0700 | [diff] [blame] | 484 | } |
| 485 | |
Tyler Hicks | 24d1526 | 2013-04-15 17:28:09 -0700 | [diff] [blame] | 486 | lower_offset = lower_offset_for_page(crypt_stat, page); |
Tyler Hicks | 0f89617 | 2013-04-15 16:16:24 -0700 | [diff] [blame] | 487 | enc_extent_virt = kmap(enc_extent_page); |
| 488 | rc = ecryptfs_write_lower(ecryptfs_inode, enc_extent_virt, lower_offset, |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 489 | PAGE_SIZE); |
Tyler Hicks | 0f89617 | 2013-04-15 16:16:24 -0700 | [diff] [blame] | 490 | kunmap(enc_extent_page); |
| 491 | if (rc < 0) { |
| 492 | ecryptfs_printk(KERN_ERR, |
| 493 | "Error attempting to write lower page; rc = [%d]\n", |
| 494 | rc); |
| 495 | goto out; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 496 | } |
Tyler Hicks | 96a7b9c | 2009-09-16 19:04:20 -0500 | [diff] [blame] | 497 | rc = 0; |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 498 | out: |
Eric Sandeen | 7fcba05 | 2008-07-28 15:46:39 -0700 | [diff] [blame] | 499 | if (enc_extent_page) { |
Eric Sandeen | 7fcba05 | 2008-07-28 15:46:39 -0700 | [diff] [blame] | 500 | __free_page(enc_extent_page); |
| 501 | } |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 502 | return rc; |
| 503 | } |
| 504 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 505 | /** |
| 506 | * ecryptfs_decrypt_page |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 507 | * @page: Page mapped from the eCryptfs inode for the file; data read |
| 508 | * and decrypted from the lower file will be written into this |
| 509 | * page |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 510 | * |
| 511 | * Decrypt an eCryptfs page. This is done on a per-extent basis. Note |
| 512 | * that eCryptfs pages may straddle the lower pages -- for instance, |
| 513 | * if the file was created on a machine with an 8K page size |
| 514 | * (resulting in an 8K header), and then the file is copied onto a |
| 515 | * host with a 32K page size, then when reading page 0 of the eCryptfs |
| 516 | * file, 24K of page 0 of the lower file will be read and decrypted, |
| 517 | * and then 8K of page 1 of the lower file will be read and decrypted. |
| 518 | * |
| 519 | * Returns zero on success; negative on error |
| 520 | */ |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 521 | int ecryptfs_decrypt_page(struct page *page) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 522 | { |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 523 | struct inode *ecryptfs_inode; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 524 | struct ecryptfs_crypt_stat *crypt_stat; |
Tyler Hicks | 9c6043f | 2013-04-06 00:41:48 -0700 | [diff] [blame] | 525 | char *page_virt; |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 526 | unsigned long extent_offset; |
Tyler Hicks | 0f89617 | 2013-04-15 16:16:24 -0700 | [diff] [blame] | 527 | loff_t lower_offset; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 528 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 529 | |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 530 | ecryptfs_inode = page->mapping->host; |
| 531 | crypt_stat = |
| 532 | &(ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat); |
Tyler Hicks | 13a791b | 2009-04-13 15:29:27 -0500 | [diff] [blame] | 533 | BUG_ON(!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)); |
Tyler Hicks | 0f89617 | 2013-04-15 16:16:24 -0700 | [diff] [blame] | 534 | |
Tyler Hicks | 24d1526 | 2013-04-15 17:28:09 -0700 | [diff] [blame] | 535 | lower_offset = lower_offset_for_page(crypt_stat, page); |
Tyler Hicks | 9c6043f | 2013-04-06 00:41:48 -0700 | [diff] [blame] | 536 | page_virt = kmap(page); |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 537 | rc = ecryptfs_read_lower(page_virt, lower_offset, PAGE_SIZE, |
Tyler Hicks | 0f89617 | 2013-04-15 16:16:24 -0700 | [diff] [blame] | 538 | ecryptfs_inode); |
Tyler Hicks | 9c6043f | 2013-04-06 00:41:48 -0700 | [diff] [blame] | 539 | kunmap(page); |
Tyler Hicks | 0f89617 | 2013-04-15 16:16:24 -0700 | [diff] [blame] | 540 | if (rc < 0) { |
| 541 | ecryptfs_printk(KERN_ERR, |
| 542 | "Error attempting to read lower page; rc = [%d]\n", |
| 543 | rc); |
Michael Halcrow | 16a72c4 | 2007-10-16 01:28:14 -0700 | [diff] [blame] | 544 | goto out; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 545 | } |
Tyler Hicks | 0f89617 | 2013-04-15 16:16:24 -0700 | [diff] [blame] | 546 | |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 547 | for (extent_offset = 0; |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 548 | extent_offset < (PAGE_SIZE / crypt_stat->extent_size); |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 549 | extent_offset++) { |
Tyler Hicks | 0df5ed6 | 2013-05-23 12:08:40 -0700 | [diff] [blame] | 550 | rc = crypt_extent(crypt_stat, page, page, |
Tyler Hicks | d78de61 | 2013-04-06 00:08:48 -0700 | [diff] [blame] | 551 | extent_offset, DECRYPT); |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 552 | if (rc) { |
| 553 | printk(KERN_ERR "%s: Error encrypting extent; " |
Harvey Harrison | 18d1dbf | 2008-04-29 00:59:48 -0700 | [diff] [blame] | 554 | "rc = [%d]\n", __func__, rc); |
Michael Halcrow | 16a72c4 | 2007-10-16 01:28:14 -0700 | [diff] [blame] | 555 | goto out; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 556 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 557 | } |
| 558 | out: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 559 | return rc; |
| 560 | } |
| 561 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 562 | #define ECRYPTFS_MAX_SCATTERLIST_LEN 4 |
| 563 | |
| 564 | /** |
| 565 | * ecryptfs_init_crypt_ctx |
Uwe Kleine-König | 421f91d | 2010-06-11 12:17:00 +0200 | [diff] [blame] | 566 | * @crypt_stat: Uninitialized crypt stats structure |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 567 | * |
| 568 | * Initialize the crypto context. |
| 569 | * |
| 570 | * TODO: Performance: Keep a cache of initialized cipher contexts; |
| 571 | * only init if needed |
| 572 | */ |
| 573 | int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat) |
| 574 | { |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 575 | char *full_alg_name; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 576 | int rc = -EINVAL; |
| 577 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 578 | ecryptfs_printk(KERN_DEBUG, |
| 579 | "Initializing cipher [%s]; strlen = [%d]; " |
Tyler Hicks | f24b388 | 2010-11-15 17:36:38 -0600 | [diff] [blame] | 580 | "key_size_bits = [%zd]\n", |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 581 | crypt_stat->cipher, (int)strlen(crypt_stat->cipher), |
| 582 | crypt_stat->key_size << 3); |
Kees Cook | cb69f36 | 2013-08-13 15:02:27 -0700 | [diff] [blame] | 583 | mutex_lock(&crypt_stat->cs_tfm_mutex); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 584 | if (crypt_stat->tfm) { |
| 585 | rc = 0; |
Kees Cook | cb69f36 | 2013-08-13 15:02:27 -0700 | [diff] [blame] | 586 | goto out_unlock; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 587 | } |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 588 | rc = ecryptfs_crypto_api_algify_cipher_name(&full_alg_name, |
| 589 | crypt_stat->cipher, "cbc"); |
| 590 | if (rc) |
Eric Sandeen | c8161f6 | 2007-12-22 14:03:26 -0800 | [diff] [blame] | 591 | goto out_unlock; |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 592 | crypt_stat->tfm = crypto_alloc_skcipher(full_alg_name, 0, 0); |
Akinobu Mita | de88777 | 2006-11-28 12:29:49 -0800 | [diff] [blame] | 593 | if (IS_ERR(crypt_stat->tfm)) { |
| 594 | rc = PTR_ERR(crypt_stat->tfm); |
Tyler Hicks | b0105ea | 2009-08-11 00:36:32 -0500 | [diff] [blame] | 595 | crypt_stat->tfm = NULL; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 596 | ecryptfs_printk(KERN_ERR, "cryptfs: init_crypt_ctx(): " |
| 597 | "Error initializing cipher [%s]\n", |
Kees Cook | cb69f36 | 2013-08-13 15:02:27 -0700 | [diff] [blame] | 598 | full_alg_name); |
| 599 | goto out_free; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 600 | } |
Eric Biggers | 231baec | 2019-01-18 22:48:00 -0800 | [diff] [blame] | 601 | crypto_skcipher_set_flags(crypt_stat->tfm, |
| 602 | CRYPTO_TFM_REQ_FORBID_WEAK_KEYS); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 603 | rc = 0; |
Kees Cook | cb69f36 | 2013-08-13 15:02:27 -0700 | [diff] [blame] | 604 | out_free: |
| 605 | kfree(full_alg_name); |
Eric Sandeen | c8161f6 | 2007-12-22 14:03:26 -0800 | [diff] [blame] | 606 | out_unlock: |
| 607 | mutex_unlock(&crypt_stat->cs_tfm_mutex); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 608 | return rc; |
| 609 | } |
| 610 | |
| 611 | static void set_extent_mask_and_shift(struct ecryptfs_crypt_stat *crypt_stat) |
| 612 | { |
| 613 | int extent_size_tmp; |
| 614 | |
| 615 | crypt_stat->extent_mask = 0xFFFFFFFF; |
| 616 | crypt_stat->extent_shift = 0; |
| 617 | if (crypt_stat->extent_size == 0) |
| 618 | return; |
| 619 | extent_size_tmp = crypt_stat->extent_size; |
| 620 | while ((extent_size_tmp & 0x01) == 0) { |
| 621 | extent_size_tmp >>= 1; |
| 622 | crypt_stat->extent_mask <<= 1; |
| 623 | crypt_stat->extent_shift++; |
| 624 | } |
| 625 | } |
| 626 | |
| 627 | void ecryptfs_set_default_sizes(struct ecryptfs_crypt_stat *crypt_stat) |
| 628 | { |
| 629 | /* Default values; may be overwritten as we are parsing the |
| 630 | * packets. */ |
| 631 | crypt_stat->extent_size = ECRYPTFS_DEFAULT_EXTENT_SIZE; |
| 632 | set_extent_mask_and_shift(crypt_stat); |
| 633 | crypt_stat->iv_bytes = ECRYPTFS_DEFAULT_IV_BYTES; |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 634 | if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) |
Tyler Hicks | fa3ef1c | 2010-02-11 05:09:14 -0600 | [diff] [blame] | 635 | crypt_stat->metadata_size = ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE; |
Michael Halcrow | 45eaab7 | 2007-10-16 01:28:05 -0700 | [diff] [blame] | 636 | else { |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 637 | if (PAGE_SIZE <= ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE) |
Tyler Hicks | fa3ef1c | 2010-02-11 05:09:14 -0600 | [diff] [blame] | 638 | crypt_stat->metadata_size = |
Michael Halcrow | cc11bef | 2008-02-06 01:38:32 -0800 | [diff] [blame] | 639 | ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE; |
Michael Halcrow | 45eaab7 | 2007-10-16 01:28:05 -0700 | [diff] [blame] | 640 | else |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 641 | crypt_stat->metadata_size = PAGE_SIZE; |
Michael Halcrow | 45eaab7 | 2007-10-16 01:28:05 -0700 | [diff] [blame] | 642 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 643 | } |
| 644 | |
| 645 | /** |
| 646 | * ecryptfs_compute_root_iv |
| 647 | * @crypt_stats |
| 648 | * |
| 649 | * On error, sets the root IV to all 0's. |
| 650 | */ |
| 651 | int ecryptfs_compute_root_iv(struct ecryptfs_crypt_stat *crypt_stat) |
| 652 | { |
| 653 | int rc = 0; |
| 654 | char dst[MD5_DIGEST_SIZE]; |
| 655 | |
| 656 | BUG_ON(crypt_stat->iv_bytes > MD5_DIGEST_SIZE); |
| 657 | BUG_ON(crypt_stat->iv_bytes <= 0); |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 658 | if (!(crypt_stat->flags & ECRYPTFS_KEY_VALID)) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 659 | rc = -EINVAL; |
| 660 | ecryptfs_printk(KERN_WARNING, "Session key not valid; " |
| 661 | "cannot generate root IV\n"); |
| 662 | goto out; |
| 663 | } |
| 664 | rc = ecryptfs_calculate_md5(dst, crypt_stat, crypt_stat->key, |
| 665 | crypt_stat->key_size); |
| 666 | if (rc) { |
| 667 | ecryptfs_printk(KERN_WARNING, "Error attempting to compute " |
| 668 | "MD5 while generating root IV\n"); |
| 669 | goto out; |
| 670 | } |
| 671 | memcpy(crypt_stat->root_iv, dst, crypt_stat->iv_bytes); |
| 672 | out: |
| 673 | if (rc) { |
| 674 | memset(crypt_stat->root_iv, 0, crypt_stat->iv_bytes); |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 675 | crypt_stat->flags |= ECRYPTFS_SECURITY_WARNING; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 676 | } |
| 677 | return rc; |
| 678 | } |
| 679 | |
| 680 | static void ecryptfs_generate_new_key(struct ecryptfs_crypt_stat *crypt_stat) |
| 681 | { |
| 682 | get_random_bytes(crypt_stat->key, crypt_stat->key_size); |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 683 | crypt_stat->flags |= ECRYPTFS_KEY_VALID; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 684 | ecryptfs_compute_root_iv(crypt_stat); |
| 685 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 686 | ecryptfs_printk(KERN_DEBUG, "Generated new session key:\n"); |
| 687 | ecryptfs_dump_hex(crypt_stat->key, |
| 688 | crypt_stat->key_size); |
| 689 | } |
| 690 | } |
| 691 | |
| 692 | /** |
Michael Halcrow | 1739895 | 2007-02-12 00:53:45 -0800 | [diff] [blame] | 693 | * ecryptfs_copy_mount_wide_flags_to_inode_flags |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 694 | * @crypt_stat: The inode's cryptographic context |
| 695 | * @mount_crypt_stat: The mount point's cryptographic context |
Michael Halcrow | 1739895 | 2007-02-12 00:53:45 -0800 | [diff] [blame] | 696 | * |
| 697 | * This function propagates the mount-wide flags to individual inode |
| 698 | * flags. |
| 699 | */ |
| 700 | static void ecryptfs_copy_mount_wide_flags_to_inode_flags( |
| 701 | struct ecryptfs_crypt_stat *crypt_stat, |
| 702 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat) |
| 703 | { |
| 704 | if (mount_crypt_stat->flags & ECRYPTFS_XATTR_METADATA_ENABLED) |
| 705 | crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR; |
| 706 | if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) |
| 707 | crypt_stat->flags |= ECRYPTFS_VIEW_AS_ENCRYPTED; |
Michael Halcrow | addd65ad | 2009-01-06 14:42:00 -0800 | [diff] [blame] | 708 | if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) { |
| 709 | crypt_stat->flags |= ECRYPTFS_ENCRYPT_FILENAMES; |
| 710 | if (mount_crypt_stat->flags |
| 711 | & ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK) |
| 712 | crypt_stat->flags |= ECRYPTFS_ENCFN_USE_MOUNT_FNEK; |
| 713 | else if (mount_crypt_stat->flags |
| 714 | & ECRYPTFS_GLOBAL_ENCFN_USE_FEK) |
| 715 | crypt_stat->flags |= ECRYPTFS_ENCFN_USE_FEK; |
| 716 | } |
Michael Halcrow | 1739895 | 2007-02-12 00:53:45 -0800 | [diff] [blame] | 717 | } |
| 718 | |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 719 | static int ecryptfs_copy_mount_wide_sigs_to_inode_sigs( |
| 720 | struct ecryptfs_crypt_stat *crypt_stat, |
| 721 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat) |
| 722 | { |
| 723 | struct ecryptfs_global_auth_tok *global_auth_tok; |
| 724 | int rc = 0; |
| 725 | |
Roland Dreier | aa06117 | 2009-07-01 15:48:18 -0700 | [diff] [blame] | 726 | mutex_lock(&crypt_stat->keysig_list_mutex); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 727 | mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex); |
Roland Dreier | aa06117 | 2009-07-01 15:48:18 -0700 | [diff] [blame] | 728 | |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 729 | list_for_each_entry(global_auth_tok, |
| 730 | &mount_crypt_stat->global_auth_tok_list, |
| 731 | mount_crypt_stat_list) { |
Tyler Hicks | 84814d6 | 2009-03-13 13:51:59 -0700 | [diff] [blame] | 732 | if (global_auth_tok->flags & ECRYPTFS_AUTH_TOK_FNEK) |
| 733 | continue; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 734 | rc = ecryptfs_add_keysig(crypt_stat, global_auth_tok->sig); |
| 735 | if (rc) { |
| 736 | printk(KERN_ERR "Error adding keysig; rc = [%d]\n", rc); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 737 | goto out; |
| 738 | } |
| 739 | } |
Roland Dreier | aa06117 | 2009-07-01 15:48:18 -0700 | [diff] [blame] | 740 | |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 741 | out: |
Roland Dreier | aa06117 | 2009-07-01 15:48:18 -0700 | [diff] [blame] | 742 | mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex); |
| 743 | mutex_unlock(&crypt_stat->keysig_list_mutex); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 744 | return rc; |
| 745 | } |
| 746 | |
Michael Halcrow | 1739895 | 2007-02-12 00:53:45 -0800 | [diff] [blame] | 747 | /** |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 748 | * ecryptfs_set_default_crypt_stat_vals |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 749 | * @crypt_stat: The inode's cryptographic context |
| 750 | * @mount_crypt_stat: The mount point's cryptographic context |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 751 | * |
| 752 | * Default values in the event that policy does not override them. |
| 753 | */ |
| 754 | static void ecryptfs_set_default_crypt_stat_vals( |
| 755 | struct ecryptfs_crypt_stat *crypt_stat, |
| 756 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat) |
| 757 | { |
Michael Halcrow | 1739895 | 2007-02-12 00:53:45 -0800 | [diff] [blame] | 758 | ecryptfs_copy_mount_wide_flags_to_inode_flags(crypt_stat, |
| 759 | mount_crypt_stat); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 760 | ecryptfs_set_default_sizes(crypt_stat); |
| 761 | strcpy(crypt_stat->cipher, ECRYPTFS_DEFAULT_CIPHER); |
| 762 | crypt_stat->key_size = ECRYPTFS_DEFAULT_KEY_BYTES; |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 763 | crypt_stat->flags &= ~(ECRYPTFS_KEY_VALID); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 764 | crypt_stat->file_version = ECRYPTFS_FILE_VERSION; |
| 765 | crypt_stat->mount_crypt_stat = mount_crypt_stat; |
| 766 | } |
| 767 | |
| 768 | /** |
| 769 | * ecryptfs_new_file_context |
Tyler Hicks | b59db43 | 2011-11-21 17:31:02 -0600 | [diff] [blame] | 770 | * @ecryptfs_inode: The eCryptfs inode |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 771 | * |
| 772 | * If the crypto context for the file has not yet been established, |
| 773 | * this is where we do that. Establishing a new crypto context |
| 774 | * involves the following decisions: |
| 775 | * - What cipher to use? |
| 776 | * - What set of authentication tokens to use? |
| 777 | * Here we just worry about getting enough information into the |
| 778 | * authentication tokens so that we know that they are available. |
| 779 | * We associate the available authentication tokens with the new file |
| 780 | * via the set of signatures in the crypt_stat struct. Later, when |
| 781 | * the headers are actually written out, we may again defer to |
| 782 | * userspace to perform the encryption of the session key; for the |
| 783 | * foreseeable future, this will be the case with public key packets. |
| 784 | * |
| 785 | * Returns zero on success; non-zero otherwise |
| 786 | */ |
Tyler Hicks | b59db43 | 2011-11-21 17:31:02 -0600 | [diff] [blame] | 787 | int ecryptfs_new_file_context(struct inode *ecryptfs_inode) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 788 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 789 | struct ecryptfs_crypt_stat *crypt_stat = |
Tyler Hicks | b59db43 | 2011-11-21 17:31:02 -0600 | [diff] [blame] | 790 | &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 791 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat = |
| 792 | &ecryptfs_superblock_to_private( |
Tyler Hicks | b59db43 | 2011-11-21 17:31:02 -0600 | [diff] [blame] | 793 | ecryptfs_inode->i_sb)->mount_crypt_stat; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 794 | int cipher_name_len; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 795 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 796 | |
| 797 | ecryptfs_set_default_crypt_stat_vals(crypt_stat, mount_crypt_stat); |
Michael Halcrow | af655dc | 2007-10-16 01:28:00 -0700 | [diff] [blame] | 798 | crypt_stat->flags |= (ECRYPTFS_ENCRYPTED | ECRYPTFS_KEY_VALID); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 799 | ecryptfs_copy_mount_wide_flags_to_inode_flags(crypt_stat, |
| 800 | mount_crypt_stat); |
| 801 | rc = ecryptfs_copy_mount_wide_sigs_to_inode_sigs(crypt_stat, |
| 802 | mount_crypt_stat); |
| 803 | if (rc) { |
| 804 | printk(KERN_ERR "Error attempting to copy mount-wide key sigs " |
| 805 | "to the inode key sigs; rc = [%d]\n", rc); |
| 806 | goto out; |
| 807 | } |
| 808 | cipher_name_len = |
| 809 | strlen(mount_crypt_stat->global_default_cipher_name); |
| 810 | memcpy(crypt_stat->cipher, |
| 811 | mount_crypt_stat->global_default_cipher_name, |
| 812 | cipher_name_len); |
| 813 | crypt_stat->cipher[cipher_name_len] = '\0'; |
| 814 | crypt_stat->key_size = |
| 815 | mount_crypt_stat->global_default_cipher_key_size; |
| 816 | ecryptfs_generate_new_key(crypt_stat); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 817 | rc = ecryptfs_init_crypt_ctx(crypt_stat); |
| 818 | if (rc) |
| 819 | ecryptfs_printk(KERN_ERR, "Error initializing cryptographic " |
| 820 | "context for cipher [%s]: rc = [%d]\n", |
| 821 | crypt_stat->cipher, rc); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 822 | out: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 823 | return rc; |
| 824 | } |
| 825 | |
| 826 | /** |
Tyler Hicks | 7a86617 | 2011-05-02 00:39:54 -0500 | [diff] [blame] | 827 | * ecryptfs_validate_marker - check for the ecryptfs marker |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 828 | * @data: The data block in which to check |
| 829 | * |
Tyler Hicks | 7a86617 | 2011-05-02 00:39:54 -0500 | [diff] [blame] | 830 | * Returns zero if marker found; -EINVAL if not found |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 831 | */ |
Tyler Hicks | 7a86617 | 2011-05-02 00:39:54 -0500 | [diff] [blame] | 832 | static int ecryptfs_validate_marker(char *data) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 833 | { |
| 834 | u32 m_1, m_2; |
| 835 | |
Harvey Harrison | 29335c6 | 2008-07-23 21:30:06 -0700 | [diff] [blame] | 836 | m_1 = get_unaligned_be32(data); |
| 837 | m_2 = get_unaligned_be32(data + 4); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 838 | if ((m_1 ^ MAGIC_ECRYPTFS_MARKER) == m_2) |
Tyler Hicks | 7a86617 | 2011-05-02 00:39:54 -0500 | [diff] [blame] | 839 | return 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 840 | ecryptfs_printk(KERN_DEBUG, "m_1 = [0x%.8x]; m_2 = [0x%.8x]; " |
| 841 | "MAGIC_ECRYPTFS_MARKER = [0x%.8x]\n", m_1, m_2, |
| 842 | MAGIC_ECRYPTFS_MARKER); |
| 843 | ecryptfs_printk(KERN_DEBUG, "(m_1 ^ MAGIC_ECRYPTFS_MARKER) = " |
| 844 | "[0x%.8x]\n", (m_1 ^ MAGIC_ECRYPTFS_MARKER)); |
Tyler Hicks | 7a86617 | 2011-05-02 00:39:54 -0500 | [diff] [blame] | 845 | return -EINVAL; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 846 | } |
| 847 | |
| 848 | struct ecryptfs_flag_map_elem { |
| 849 | u32 file_flag; |
| 850 | u32 local_flag; |
| 851 | }; |
| 852 | |
| 853 | /* Add support for additional flags by adding elements here. */ |
| 854 | static struct ecryptfs_flag_map_elem ecryptfs_flag_map[] = { |
| 855 | {0x00000001, ECRYPTFS_ENABLE_HMAC}, |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 856 | {0x00000002, ECRYPTFS_ENCRYPTED}, |
Michael Halcrow | addd65ad | 2009-01-06 14:42:00 -0800 | [diff] [blame] | 857 | {0x00000004, ECRYPTFS_METADATA_IN_XATTR}, |
| 858 | {0x00000008, ECRYPTFS_ENCRYPT_FILENAMES} |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 859 | }; |
| 860 | |
| 861 | /** |
| 862 | * ecryptfs_process_flags |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 863 | * @crypt_stat: The cryptographic context |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 864 | * @page_virt: Source data to be parsed |
| 865 | * @bytes_read: Updated with the number of bytes read |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 866 | */ |
Hariprasad Kelam | 7451c54 | 2019-07-02 23:17:24 +0530 | [diff] [blame] | 867 | static void ecryptfs_process_flags(struct ecryptfs_crypt_stat *crypt_stat, |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 868 | char *page_virt, int *bytes_read) |
| 869 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 870 | int i; |
| 871 | u32 flags; |
| 872 | |
Harvey Harrison | 29335c6 | 2008-07-23 21:30:06 -0700 | [diff] [blame] | 873 | flags = get_unaligned_be32(page_virt); |
Jérémy Lefaure | 02f9876 | 2017-10-01 15:30:46 -0400 | [diff] [blame] | 874 | for (i = 0; i < ARRAY_SIZE(ecryptfs_flag_map); i++) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 875 | if (flags & ecryptfs_flag_map[i].file_flag) { |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 876 | crypt_stat->flags |= ecryptfs_flag_map[i].local_flag; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 877 | } else |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 878 | crypt_stat->flags &= ~(ecryptfs_flag_map[i].local_flag); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 879 | /* Version is in top 8 bits of the 32-bit flag vector */ |
| 880 | crypt_stat->file_version = ((flags >> 24) & 0xFF); |
| 881 | (*bytes_read) = 4; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 882 | } |
| 883 | |
| 884 | /** |
| 885 | * write_ecryptfs_marker |
| 886 | * @page_virt: The pointer to in a page to begin writing the marker |
| 887 | * @written: Number of bytes written |
| 888 | * |
| 889 | * Marker = 0x3c81b7f5 |
| 890 | */ |
| 891 | static void write_ecryptfs_marker(char *page_virt, size_t *written) |
| 892 | { |
| 893 | u32 m_1, m_2; |
| 894 | |
| 895 | get_random_bytes(&m_1, (MAGIC_ECRYPTFS_MARKER_SIZE_BYTES / 2)); |
| 896 | m_2 = (m_1 ^ MAGIC_ECRYPTFS_MARKER); |
Harvey Harrison | 29335c6 | 2008-07-23 21:30:06 -0700 | [diff] [blame] | 897 | put_unaligned_be32(m_1, page_virt); |
| 898 | page_virt += (MAGIC_ECRYPTFS_MARKER_SIZE_BYTES / 2); |
| 899 | put_unaligned_be32(m_2, page_virt); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 900 | (*written) = MAGIC_ECRYPTFS_MARKER_SIZE_BYTES; |
| 901 | } |
| 902 | |
Tyler Hicks | f4e60e6 | 2010-02-11 00:02:32 -0600 | [diff] [blame] | 903 | void ecryptfs_write_crypt_stat_flags(char *page_virt, |
| 904 | struct ecryptfs_crypt_stat *crypt_stat, |
| 905 | size_t *written) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 906 | { |
| 907 | u32 flags = 0; |
| 908 | int i; |
| 909 | |
Jérémy Lefaure | 02f9876 | 2017-10-01 15:30:46 -0400 | [diff] [blame] | 910 | for (i = 0; i < ARRAY_SIZE(ecryptfs_flag_map); i++) |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 911 | if (crypt_stat->flags & ecryptfs_flag_map[i].local_flag) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 912 | flags |= ecryptfs_flag_map[i].file_flag; |
| 913 | /* Version is in top 8 bits of the 32-bit flag vector */ |
| 914 | flags |= ((((u8)crypt_stat->file_version) << 24) & 0xFF000000); |
Harvey Harrison | 29335c6 | 2008-07-23 21:30:06 -0700 | [diff] [blame] | 915 | put_unaligned_be32(flags, page_virt); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 916 | (*written) = 4; |
| 917 | } |
| 918 | |
| 919 | struct ecryptfs_cipher_code_str_map_elem { |
| 920 | char cipher_str[16]; |
Trevor Highland | 19e66a6 | 2008-02-06 01:38:36 -0800 | [diff] [blame] | 921 | u8 cipher_code; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 922 | }; |
| 923 | |
| 924 | /* Add support for additional ciphers by adding elements here. The |
Chris J Arges | 40f0fd3 | 2016-06-09 15:31:29 -0500 | [diff] [blame] | 925 | * cipher_code is whatever OpenPGP applications use to identify the |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 926 | * ciphers. List in order of probability. */ |
| 927 | static struct ecryptfs_cipher_code_str_map_elem |
| 928 | ecryptfs_cipher_code_str_map[] = { |
| 929 | {"aes",RFC2440_CIPHER_AES_128 }, |
| 930 | {"blowfish", RFC2440_CIPHER_BLOWFISH}, |
| 931 | {"des3_ede", RFC2440_CIPHER_DES3_EDE}, |
| 932 | {"cast5", RFC2440_CIPHER_CAST_5}, |
| 933 | {"twofish", RFC2440_CIPHER_TWOFISH}, |
| 934 | {"cast6", RFC2440_CIPHER_CAST_6}, |
| 935 | {"aes", RFC2440_CIPHER_AES_192}, |
| 936 | {"aes", RFC2440_CIPHER_AES_256} |
| 937 | }; |
| 938 | |
| 939 | /** |
| 940 | * ecryptfs_code_for_cipher_string |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 941 | * @cipher_name: The string alias for the cipher |
| 942 | * @key_bytes: Length of key in bytes; used for AES code selection |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 943 | * |
| 944 | * Returns zero on no match, or the cipher code on match |
| 945 | */ |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 946 | u8 ecryptfs_code_for_cipher_string(char *cipher_name, size_t key_bytes) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 947 | { |
| 948 | int i; |
Trevor Highland | 19e66a6 | 2008-02-06 01:38:36 -0800 | [diff] [blame] | 949 | u8 code = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 950 | struct ecryptfs_cipher_code_str_map_elem *map = |
| 951 | ecryptfs_cipher_code_str_map; |
| 952 | |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 953 | if (strcmp(cipher_name, "aes") == 0) { |
| 954 | switch (key_bytes) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 955 | case 16: |
| 956 | code = RFC2440_CIPHER_AES_128; |
| 957 | break; |
| 958 | case 24: |
| 959 | code = RFC2440_CIPHER_AES_192; |
| 960 | break; |
| 961 | case 32: |
| 962 | code = RFC2440_CIPHER_AES_256; |
| 963 | } |
| 964 | } else { |
| 965 | for (i = 0; i < ARRAY_SIZE(ecryptfs_cipher_code_str_map); i++) |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 966 | if (strcmp(cipher_name, map[i].cipher_str) == 0) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 967 | code = map[i].cipher_code; |
| 968 | break; |
| 969 | } |
| 970 | } |
| 971 | return code; |
| 972 | } |
| 973 | |
| 974 | /** |
| 975 | * ecryptfs_cipher_code_to_string |
| 976 | * @str: Destination to write out the cipher name |
| 977 | * @cipher_code: The code to convert to cipher name string |
| 978 | * |
| 979 | * Returns zero on success |
| 980 | */ |
Trevor Highland | 19e66a6 | 2008-02-06 01:38:36 -0800 | [diff] [blame] | 981 | int ecryptfs_cipher_code_to_string(char *str, u8 cipher_code) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 982 | { |
| 983 | int rc = 0; |
| 984 | int i; |
| 985 | |
| 986 | str[0] = '\0'; |
| 987 | for (i = 0; i < ARRAY_SIZE(ecryptfs_cipher_code_str_map); i++) |
| 988 | if (cipher_code == ecryptfs_cipher_code_str_map[i].cipher_code) |
| 989 | strcpy(str, ecryptfs_cipher_code_str_map[i].cipher_str); |
| 990 | if (str[0] == '\0') { |
| 991 | ecryptfs_printk(KERN_WARNING, "Cipher code not recognized: " |
| 992 | "[%d]\n", cipher_code); |
| 993 | rc = -EINVAL; |
| 994 | } |
| 995 | return rc; |
| 996 | } |
| 997 | |
Tyler Hicks | 778aeb4 | 2011-05-24 04:56:23 -0500 | [diff] [blame] | 998 | int ecryptfs_read_and_validate_header_region(struct inode *inode) |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 999 | { |
Tyler Hicks | 778aeb4 | 2011-05-24 04:56:23 -0500 | [diff] [blame] | 1000 | u8 file_size[ECRYPTFS_SIZE_AND_MARKER_BYTES]; |
| 1001 | u8 *marker = file_size + ECRYPTFS_FILE_SIZE_BYTES; |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1002 | int rc; |
| 1003 | |
Tyler Hicks | 778aeb4 | 2011-05-24 04:56:23 -0500 | [diff] [blame] | 1004 | rc = ecryptfs_read_lower(file_size, 0, ECRYPTFS_SIZE_AND_MARKER_BYTES, |
| 1005 | inode); |
Dan Carpenter | 0bdf8a8 | 2018-07-04 12:35:56 +0300 | [diff] [blame] | 1006 | if (rc < 0) |
| 1007 | return rc; |
| 1008 | else if (rc < ECRYPTFS_SIZE_AND_MARKER_BYTES) |
| 1009 | return -EINVAL; |
Tyler Hicks | 778aeb4 | 2011-05-24 04:56:23 -0500 | [diff] [blame] | 1010 | rc = ecryptfs_validate_marker(marker); |
| 1011 | if (!rc) |
| 1012 | ecryptfs_i_size_init(file_size, inode); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1013 | return rc; |
| 1014 | } |
| 1015 | |
Michael Halcrow | e77a56d | 2007-02-12 00:53:47 -0800 | [diff] [blame] | 1016 | void |
| 1017 | ecryptfs_write_header_metadata(char *virt, |
| 1018 | struct ecryptfs_crypt_stat *crypt_stat, |
| 1019 | size_t *written) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1020 | { |
| 1021 | u32 header_extent_size; |
| 1022 | u16 num_header_extents_at_front; |
| 1023 | |
Michael Halcrow | 45eaab7 | 2007-10-16 01:28:05 -0700 | [diff] [blame] | 1024 | header_extent_size = (u32)crypt_stat->extent_size; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1025 | num_header_extents_at_front = |
Tyler Hicks | fa3ef1c | 2010-02-11 05:09:14 -0600 | [diff] [blame] | 1026 | (u16)(crypt_stat->metadata_size / crypt_stat->extent_size); |
Harvey Harrison | 29335c6 | 2008-07-23 21:30:06 -0700 | [diff] [blame] | 1027 | put_unaligned_be32(header_extent_size, virt); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1028 | virt += 4; |
Harvey Harrison | 29335c6 | 2008-07-23 21:30:06 -0700 | [diff] [blame] | 1029 | put_unaligned_be16(num_header_extents_at_front, virt); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1030 | (*written) = 6; |
| 1031 | } |
| 1032 | |
Tyler Hicks | 3063287 | 2011-05-24 05:11:12 -0500 | [diff] [blame] | 1033 | struct kmem_cache *ecryptfs_header_cache; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1034 | |
| 1035 | /** |
| 1036 | * ecryptfs_write_headers_virt |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1037 | * @page_virt: The virtual address to write the headers to |
Eric Sandeen | 87b811c3 | 2008-10-29 14:01:08 -0700 | [diff] [blame] | 1038 | * @max: The size of memory allocated at page_virt |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1039 | * @size: Set to the number of bytes written by this function |
| 1040 | * @crypt_stat: The cryptographic context |
| 1041 | * @ecryptfs_dentry: The eCryptfs dentry |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1042 | * |
| 1043 | * Format version: 1 |
| 1044 | * |
| 1045 | * Header Extent: |
| 1046 | * Octets 0-7: Unencrypted file size (big-endian) |
| 1047 | * Octets 8-15: eCryptfs special marker |
| 1048 | * Octets 16-19: Flags |
| 1049 | * Octet 16: File format version number (between 0 and 255) |
| 1050 | * Octets 17-18: Reserved |
| 1051 | * Octet 19: Bit 1 (lsb): Reserved |
| 1052 | * Bit 2: Encrypted? |
| 1053 | * Bits 3-8: Reserved |
| 1054 | * Octets 20-23: Header extent size (big-endian) |
| 1055 | * Octets 24-25: Number of header extents at front of file |
| 1056 | * (big-endian) |
| 1057 | * Octet 26: Begin RFC 2440 authentication token packet set |
| 1058 | * Data Extent 0: |
| 1059 | * Lower data (CBC encrypted) |
| 1060 | * Data Extent 1: |
| 1061 | * Lower data (CBC encrypted) |
| 1062 | * ... |
| 1063 | * |
| 1064 | * Returns zero on success |
| 1065 | */ |
Eric Sandeen | 87b811c3 | 2008-10-29 14:01:08 -0700 | [diff] [blame] | 1066 | static int ecryptfs_write_headers_virt(char *page_virt, size_t max, |
| 1067 | size_t *size, |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1068 | struct ecryptfs_crypt_stat *crypt_stat, |
| 1069 | struct dentry *ecryptfs_dentry) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1070 | { |
| 1071 | int rc; |
| 1072 | size_t written; |
| 1073 | size_t offset; |
| 1074 | |
| 1075 | offset = ECRYPTFS_FILE_SIZE_BYTES; |
| 1076 | write_ecryptfs_marker((page_virt + offset), &written); |
| 1077 | offset += written; |
Tyler Hicks | f4e60e6 | 2010-02-11 00:02:32 -0600 | [diff] [blame] | 1078 | ecryptfs_write_crypt_stat_flags((page_virt + offset), crypt_stat, |
| 1079 | &written); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1080 | offset += written; |
Michael Halcrow | e77a56d | 2007-02-12 00:53:47 -0800 | [diff] [blame] | 1081 | ecryptfs_write_header_metadata((page_virt + offset), crypt_stat, |
| 1082 | &written); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1083 | offset += written; |
| 1084 | rc = ecryptfs_generate_key_packet_set((page_virt + offset), crypt_stat, |
| 1085 | ecryptfs_dentry, &written, |
Eric Sandeen | 87b811c3 | 2008-10-29 14:01:08 -0700 | [diff] [blame] | 1086 | max - offset); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1087 | if (rc) |
| 1088 | ecryptfs_printk(KERN_WARNING, "Error generating key packet " |
| 1089 | "set; rc = [%d]\n", rc); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1090 | if (size) { |
| 1091 | offset += written; |
| 1092 | *size = offset; |
| 1093 | } |
| 1094 | return rc; |
| 1095 | } |
| 1096 | |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1097 | static int |
Tyler Hicks | b59db43 | 2011-11-21 17:31:02 -0600 | [diff] [blame] | 1098 | ecryptfs_write_metadata_to_contents(struct inode *ecryptfs_inode, |
Tyler Hicks | 8faece5 | 2009-03-20 01:25:09 -0500 | [diff] [blame] | 1099 | char *virt, size_t virt_len) |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1100 | { |
Michael Halcrow | d7cdc5f | 2007-10-16 01:28:10 -0700 | [diff] [blame] | 1101 | int rc; |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1102 | |
Tyler Hicks | b59db43 | 2011-11-21 17:31:02 -0600 | [diff] [blame] | 1103 | rc = ecryptfs_write_lower(ecryptfs_inode, virt, |
Tyler Hicks | 8faece5 | 2009-03-20 01:25:09 -0500 | [diff] [blame] | 1104 | 0, virt_len); |
Tyler Hicks | 96a7b9c | 2009-09-16 19:04:20 -0500 | [diff] [blame] | 1105 | if (rc < 0) |
Michael Halcrow | d7cdc5f | 2007-10-16 01:28:10 -0700 | [diff] [blame] | 1106 | printk(KERN_ERR "%s: Error attempting to write header " |
Tyler Hicks | 96a7b9c | 2009-09-16 19:04:20 -0500 | [diff] [blame] | 1107 | "information to lower file; rc = [%d]\n", __func__, rc); |
| 1108 | else |
| 1109 | rc = 0; |
Michael Halcrow | 7045660 | 2007-02-12 00:53:48 -0800 | [diff] [blame] | 1110 | return rc; |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1111 | } |
| 1112 | |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1113 | static int |
| 1114 | ecryptfs_write_metadata_to_xattr(struct dentry *ecryptfs_dentry, |
Al Viro | 3767e25 | 2016-05-27 11:06:05 -0400 | [diff] [blame] | 1115 | struct inode *ecryptfs_inode, |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1116 | char *page_virt, size_t size) |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1117 | { |
| 1118 | int rc; |
Robbie Ko | d43388d | 2018-08-21 16:17:40 +0800 | [diff] [blame] | 1119 | struct dentry *lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry); |
| 1120 | struct inode *lower_inode = d_inode(lower_dentry); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1121 | |
Robbie Ko | d43388d | 2018-08-21 16:17:40 +0800 | [diff] [blame] | 1122 | if (!(lower_inode->i_opflags & IOP_XATTR)) { |
| 1123 | rc = -EOPNOTSUPP; |
| 1124 | goto out; |
| 1125 | } |
| 1126 | |
| 1127 | inode_lock(lower_inode); |
| 1128 | rc = __vfs_setxattr(lower_dentry, lower_inode, ECRYPTFS_XATTR_NAME, |
| 1129 | page_virt, size, 0); |
| 1130 | if (!rc && ecryptfs_inode) |
| 1131 | fsstack_copy_attr_all(ecryptfs_inode, lower_inode); |
| 1132 | inode_unlock(lower_inode); |
| 1133 | out: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1134 | return rc; |
| 1135 | } |
| 1136 | |
Tyler Hicks | 8faece5 | 2009-03-20 01:25:09 -0500 | [diff] [blame] | 1137 | static unsigned long ecryptfs_get_zeroed_pages(gfp_t gfp_mask, |
| 1138 | unsigned int order) |
| 1139 | { |
| 1140 | struct page *page; |
| 1141 | |
| 1142 | page = alloc_pages(gfp_mask | __GFP_ZERO, order); |
| 1143 | if (page) |
| 1144 | return (unsigned long) page_address(page); |
| 1145 | return 0; |
| 1146 | } |
| 1147 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1148 | /** |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1149 | * ecryptfs_write_metadata |
Tyler Hicks | b59db43 | 2011-11-21 17:31:02 -0600 | [diff] [blame] | 1150 | * @ecryptfs_dentry: The eCryptfs dentry, which should be negative |
| 1151 | * @ecryptfs_inode: The newly created eCryptfs inode |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1152 | * |
| 1153 | * Write the file headers out. This will likely involve a userspace |
| 1154 | * callout, in which the session key is encrypted with one or more |
| 1155 | * public keys and/or the passphrase necessary to do the encryption is |
| 1156 | * retrieved via a prompt. Exactly what happens at this point should |
| 1157 | * be policy-dependent. |
| 1158 | * |
| 1159 | * Returns zero on success; non-zero on error |
| 1160 | */ |
Tyler Hicks | b59db43 | 2011-11-21 17:31:02 -0600 | [diff] [blame] | 1161 | int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry, |
| 1162 | struct inode *ecryptfs_inode) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1163 | { |
Michael Halcrow | d7cdc5f | 2007-10-16 01:28:10 -0700 | [diff] [blame] | 1164 | struct ecryptfs_crypt_stat *crypt_stat = |
Tyler Hicks | b59db43 | 2011-11-21 17:31:02 -0600 | [diff] [blame] | 1165 | &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat; |
Tyler Hicks | 8faece5 | 2009-03-20 01:25:09 -0500 | [diff] [blame] | 1166 | unsigned int order; |
Michael Halcrow | cc11bef | 2008-02-06 01:38:32 -0800 | [diff] [blame] | 1167 | char *virt; |
Tyler Hicks | 8faece5 | 2009-03-20 01:25:09 -0500 | [diff] [blame] | 1168 | size_t virt_len; |
Michael Halcrow | d7cdc5f | 2007-10-16 01:28:10 -0700 | [diff] [blame] | 1169 | size_t size = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1170 | int rc = 0; |
| 1171 | |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1172 | if (likely(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) { |
| 1173 | if (!(crypt_stat->flags & ECRYPTFS_KEY_VALID)) { |
Michael Halcrow | d7cdc5f | 2007-10-16 01:28:10 -0700 | [diff] [blame] | 1174 | printk(KERN_ERR "Key is invalid; bailing out\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1175 | rc = -EINVAL; |
| 1176 | goto out; |
| 1177 | } |
| 1178 | } else { |
Michael Halcrow | cc11bef | 2008-02-06 01:38:32 -0800 | [diff] [blame] | 1179 | printk(KERN_WARNING "%s: Encrypted flag not set\n", |
Harvey Harrison | 18d1dbf | 2008-04-29 00:59:48 -0700 | [diff] [blame] | 1180 | __func__); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1181 | rc = -EINVAL; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1182 | goto out; |
| 1183 | } |
Tyler Hicks | fa3ef1c | 2010-02-11 05:09:14 -0600 | [diff] [blame] | 1184 | virt_len = crypt_stat->metadata_size; |
Tyler Hicks | 8faece5 | 2009-03-20 01:25:09 -0500 | [diff] [blame] | 1185 | order = get_order(virt_len); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1186 | /* Released in this function */ |
Tyler Hicks | 8faece5 | 2009-03-20 01:25:09 -0500 | [diff] [blame] | 1187 | virt = (char *)ecryptfs_get_zeroed_pages(GFP_KERNEL, order); |
Michael Halcrow | cc11bef | 2008-02-06 01:38:32 -0800 | [diff] [blame] | 1188 | if (!virt) { |
Harvey Harrison | 18d1dbf | 2008-04-29 00:59:48 -0700 | [diff] [blame] | 1189 | printk(KERN_ERR "%s: Out of memory\n", __func__); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1190 | rc = -ENOMEM; |
| 1191 | goto out; |
| 1192 | } |
Tyler Hicks | bd4f0fe | 2011-02-23 00:14:19 -0600 | [diff] [blame] | 1193 | /* Zeroed page ensures the in-header unencrypted i_size is set to 0 */ |
Tyler Hicks | 8faece5 | 2009-03-20 01:25:09 -0500 | [diff] [blame] | 1194 | rc = ecryptfs_write_headers_virt(virt, virt_len, &size, crypt_stat, |
| 1195 | ecryptfs_dentry); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1196 | if (unlikely(rc)) { |
Michael Halcrow | cc11bef | 2008-02-06 01:38:32 -0800 | [diff] [blame] | 1197 | printk(KERN_ERR "%s: Error whilst writing headers; rc = [%d]\n", |
Harvey Harrison | 18d1dbf | 2008-04-29 00:59:48 -0700 | [diff] [blame] | 1198 | __func__, rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1199 | goto out_free; |
| 1200 | } |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1201 | if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) |
Al Viro | 3767e25 | 2016-05-27 11:06:05 -0400 | [diff] [blame] | 1202 | rc = ecryptfs_write_metadata_to_xattr(ecryptfs_dentry, ecryptfs_inode, |
| 1203 | virt, size); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1204 | else |
Tyler Hicks | b59db43 | 2011-11-21 17:31:02 -0600 | [diff] [blame] | 1205 | rc = ecryptfs_write_metadata_to_contents(ecryptfs_inode, virt, |
Tyler Hicks | 8faece5 | 2009-03-20 01:25:09 -0500 | [diff] [blame] | 1206 | virt_len); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1207 | if (rc) { |
Michael Halcrow | cc11bef | 2008-02-06 01:38:32 -0800 | [diff] [blame] | 1208 | printk(KERN_ERR "%s: Error writing metadata out to lower file; " |
Harvey Harrison | 18d1dbf | 2008-04-29 00:59:48 -0700 | [diff] [blame] | 1209 | "rc = [%d]\n", __func__, rc); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1210 | goto out_free; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1211 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1212 | out_free: |
Tyler Hicks | 8faece5 | 2009-03-20 01:25:09 -0500 | [diff] [blame] | 1213 | free_pages((unsigned long)virt, order); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1214 | out: |
| 1215 | return rc; |
| 1216 | } |
| 1217 | |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1218 | #define ECRYPTFS_DONT_VALIDATE_HEADER_SIZE 0 |
| 1219 | #define ECRYPTFS_VALIDATE_HEADER_SIZE 1 |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1220 | static int parse_header_metadata(struct ecryptfs_crypt_stat *crypt_stat, |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1221 | char *virt, int *bytes_read, |
| 1222 | int validate_header_size) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1223 | { |
| 1224 | int rc = 0; |
| 1225 | u32 header_extent_size; |
| 1226 | u16 num_header_extents_at_front; |
| 1227 | |
Harvey Harrison | 29335c6 | 2008-07-23 21:30:06 -0700 | [diff] [blame] | 1228 | header_extent_size = get_unaligned_be32(virt); |
| 1229 | virt += sizeof(__be32); |
| 1230 | num_header_extents_at_front = get_unaligned_be16(virt); |
Tyler Hicks | fa3ef1c | 2010-02-11 05:09:14 -0600 | [diff] [blame] | 1231 | crypt_stat->metadata_size = (((size_t)num_header_extents_at_front |
| 1232 | * (size_t)header_extent_size)); |
Harvey Harrison | 29335c6 | 2008-07-23 21:30:06 -0700 | [diff] [blame] | 1233 | (*bytes_read) = (sizeof(__be32) + sizeof(__be16)); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1234 | if ((validate_header_size == ECRYPTFS_VALIDATE_HEADER_SIZE) |
Tyler Hicks | fa3ef1c | 2010-02-11 05:09:14 -0600 | [diff] [blame] | 1235 | && (crypt_stat->metadata_size |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1236 | < ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE)) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1237 | rc = -EINVAL; |
Michael Halcrow | cc11bef | 2008-02-06 01:38:32 -0800 | [diff] [blame] | 1238 | printk(KERN_WARNING "Invalid header size: [%zd]\n", |
Tyler Hicks | fa3ef1c | 2010-02-11 05:09:14 -0600 | [diff] [blame] | 1239 | crypt_stat->metadata_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1240 | } |
| 1241 | return rc; |
| 1242 | } |
| 1243 | |
| 1244 | /** |
| 1245 | * set_default_header_data |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1246 | * @crypt_stat: The cryptographic context |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1247 | * |
| 1248 | * For version 0 file format; this function is only for backwards |
| 1249 | * compatibility for files created with the prior versions of |
| 1250 | * eCryptfs. |
| 1251 | */ |
| 1252 | static void set_default_header_data(struct ecryptfs_crypt_stat *crypt_stat) |
| 1253 | { |
Tyler Hicks | fa3ef1c | 2010-02-11 05:09:14 -0600 | [diff] [blame] | 1254 | crypt_stat->metadata_size = ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1255 | } |
| 1256 | |
Tyler Hicks | 3aeb86e | 2011-03-15 14:54:00 -0500 | [diff] [blame] | 1257 | void ecryptfs_i_size_init(const char *page_virt, struct inode *inode) |
| 1258 | { |
| 1259 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat; |
| 1260 | struct ecryptfs_crypt_stat *crypt_stat; |
| 1261 | u64 file_size; |
| 1262 | |
| 1263 | crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat; |
| 1264 | mount_crypt_stat = |
| 1265 | &ecryptfs_superblock_to_private(inode->i_sb)->mount_crypt_stat; |
| 1266 | if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) { |
| 1267 | file_size = i_size_read(ecryptfs_inode_to_lower(inode)); |
| 1268 | if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) |
| 1269 | file_size += crypt_stat->metadata_size; |
| 1270 | } else |
| 1271 | file_size = get_unaligned_be64(page_virt); |
| 1272 | i_size_write(inode, (loff_t)file_size); |
| 1273 | crypt_stat->flags |= ECRYPTFS_I_SIZE_INITIALIZED; |
| 1274 | } |
| 1275 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1276 | /** |
| 1277 | * ecryptfs_read_headers_virt |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1278 | * @page_virt: The virtual address into which to read the headers |
| 1279 | * @crypt_stat: The cryptographic context |
| 1280 | * @ecryptfs_dentry: The eCryptfs dentry |
| 1281 | * @validate_header_size: Whether to validate the header size while reading |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1282 | * |
| 1283 | * Read/parse the header data. The header format is detailed in the |
| 1284 | * comment block for the ecryptfs_write_headers_virt() function. |
| 1285 | * |
| 1286 | * Returns zero on success |
| 1287 | */ |
| 1288 | static int ecryptfs_read_headers_virt(char *page_virt, |
| 1289 | struct ecryptfs_crypt_stat *crypt_stat, |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1290 | struct dentry *ecryptfs_dentry, |
| 1291 | int validate_header_size) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1292 | { |
| 1293 | int rc = 0; |
| 1294 | int offset; |
| 1295 | int bytes_read; |
| 1296 | |
| 1297 | ecryptfs_set_default_sizes(crypt_stat); |
| 1298 | crypt_stat->mount_crypt_stat = &ecryptfs_superblock_to_private( |
| 1299 | ecryptfs_dentry->d_sb)->mount_crypt_stat; |
| 1300 | offset = ECRYPTFS_FILE_SIZE_BYTES; |
Tyler Hicks | 7a86617 | 2011-05-02 00:39:54 -0500 | [diff] [blame] | 1301 | rc = ecryptfs_validate_marker(page_virt + offset); |
| 1302 | if (rc) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1303 | goto out; |
Tyler Hicks | 3aeb86e | 2011-03-15 14:54:00 -0500 | [diff] [blame] | 1304 | if (!(crypt_stat->flags & ECRYPTFS_I_SIZE_INITIALIZED)) |
David Howells | 2b0143b | 2015-03-17 22:25:59 +0000 | [diff] [blame] | 1305 | ecryptfs_i_size_init(page_virt, d_inode(ecryptfs_dentry)); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1306 | offset += MAGIC_ECRYPTFS_MARKER_SIZE_BYTES; |
Hariprasad Kelam | 7451c54 | 2019-07-02 23:17:24 +0530 | [diff] [blame] | 1307 | ecryptfs_process_flags(crypt_stat, (page_virt + offset), &bytes_read); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1308 | if (crypt_stat->file_version > ECRYPTFS_SUPPORTED_FILE_VERSION) { |
| 1309 | ecryptfs_printk(KERN_WARNING, "File version is [%d]; only " |
| 1310 | "file version [%d] is supported by this " |
| 1311 | "version of eCryptfs\n", |
| 1312 | crypt_stat->file_version, |
| 1313 | ECRYPTFS_SUPPORTED_FILE_VERSION); |
| 1314 | rc = -EINVAL; |
| 1315 | goto out; |
| 1316 | } |
| 1317 | offset += bytes_read; |
| 1318 | if (crypt_stat->file_version >= 1) { |
| 1319 | rc = parse_header_metadata(crypt_stat, (page_virt + offset), |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1320 | &bytes_read, validate_header_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1321 | if (rc) { |
| 1322 | ecryptfs_printk(KERN_WARNING, "Error reading header " |
| 1323 | "metadata; rc = [%d]\n", rc); |
| 1324 | } |
| 1325 | offset += bytes_read; |
| 1326 | } else |
| 1327 | set_default_header_data(crypt_stat); |
| 1328 | rc = ecryptfs_parse_packet_set(crypt_stat, (page_virt + offset), |
| 1329 | ecryptfs_dentry); |
| 1330 | out: |
| 1331 | return rc; |
| 1332 | } |
| 1333 | |
| 1334 | /** |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1335 | * ecryptfs_read_xattr_region |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1336 | * @page_virt: The vitual address into which to read the xattr data |
Michael Halcrow | 2ed9255 | 2007-10-16 01:28:10 -0700 | [diff] [blame] | 1337 | * @ecryptfs_inode: The eCryptfs inode |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1338 | * |
| 1339 | * Attempts to read the crypto metadata from the extended attribute |
| 1340 | * region of the lower file. |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1341 | * |
| 1342 | * Returns zero on success; non-zero on error |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1343 | */ |
Michael Halcrow | d7cdc5f | 2007-10-16 01:28:10 -0700 | [diff] [blame] | 1344 | int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode) |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1345 | { |
Michael Halcrow | d7cdc5f | 2007-10-16 01:28:10 -0700 | [diff] [blame] | 1346 | struct dentry *lower_dentry = |
Al Viro | b583043 | 2014-10-31 01:22:04 -0400 | [diff] [blame] | 1347 | ecryptfs_inode_to_private(ecryptfs_inode)->lower_file->f_path.dentry; |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1348 | ssize_t size; |
| 1349 | int rc = 0; |
| 1350 | |
Al Viro | ce23e64 | 2016-04-11 00:48:00 -0400 | [diff] [blame] | 1351 | size = ecryptfs_getxattr_lower(lower_dentry, |
| 1352 | ecryptfs_inode_to_lower(ecryptfs_inode), |
| 1353 | ECRYPTFS_XATTR_NAME, |
Michael Halcrow | d7cdc5f | 2007-10-16 01:28:10 -0700 | [diff] [blame] | 1354 | page_virt, ECRYPTFS_DEFAULT_EXTENT_SIZE); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1355 | if (size < 0) { |
Michael Halcrow | 25bd817 | 2008-02-06 01:38:35 -0800 | [diff] [blame] | 1356 | if (unlikely(ecryptfs_verbosity > 0)) |
| 1357 | printk(KERN_INFO "Error attempting to read the [%s] " |
| 1358 | "xattr from the lower file; return value = " |
| 1359 | "[%zd]\n", ECRYPTFS_XATTR_NAME, size); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1360 | rc = -EINVAL; |
| 1361 | goto out; |
| 1362 | } |
| 1363 | out: |
| 1364 | return rc; |
| 1365 | } |
| 1366 | |
Tyler Hicks | 778aeb4 | 2011-05-24 04:56:23 -0500 | [diff] [blame] | 1367 | int ecryptfs_read_and_validate_xattr_region(struct dentry *dentry, |
Tyler Hicks | 3b06b3e | 2011-05-24 03:49:02 -0500 | [diff] [blame] | 1368 | struct inode *inode) |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1369 | { |
Tyler Hicks | 778aeb4 | 2011-05-24 04:56:23 -0500 | [diff] [blame] | 1370 | u8 file_size[ECRYPTFS_SIZE_AND_MARKER_BYTES]; |
| 1371 | u8 *marker = file_size + ECRYPTFS_FILE_SIZE_BYTES; |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1372 | int rc; |
| 1373 | |
Tyler Hicks | 778aeb4 | 2011-05-24 04:56:23 -0500 | [diff] [blame] | 1374 | rc = ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry), |
Al Viro | ce23e64 | 2016-04-11 00:48:00 -0400 | [diff] [blame] | 1375 | ecryptfs_inode_to_lower(inode), |
Tyler Hicks | 778aeb4 | 2011-05-24 04:56:23 -0500 | [diff] [blame] | 1376 | ECRYPTFS_XATTR_NAME, file_size, |
| 1377 | ECRYPTFS_SIZE_AND_MARKER_BYTES); |
Dan Carpenter | 0bdf8a8 | 2018-07-04 12:35:56 +0300 | [diff] [blame] | 1378 | if (rc < 0) |
| 1379 | return rc; |
| 1380 | else if (rc < ECRYPTFS_SIZE_AND_MARKER_BYTES) |
| 1381 | return -EINVAL; |
Tyler Hicks | 778aeb4 | 2011-05-24 04:56:23 -0500 | [diff] [blame] | 1382 | rc = ecryptfs_validate_marker(marker); |
| 1383 | if (!rc) |
| 1384 | ecryptfs_i_size_init(file_size, inode); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1385 | return rc; |
| 1386 | } |
| 1387 | |
| 1388 | /** |
| 1389 | * ecryptfs_read_metadata |
| 1390 | * |
| 1391 | * Common entry point for reading file metadata. From here, we could |
| 1392 | * retrieve the header information from the header region of the file, |
Chris J Arges | 40f0fd3 | 2016-06-09 15:31:29 -0500 | [diff] [blame] | 1393 | * the xattr region of the file, or some other repository that is |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1394 | * stored separately from the file itself. The current implementation |
| 1395 | * supports retrieving the metadata information from the file contents |
| 1396 | * and from the xattr region. |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1397 | * |
| 1398 | * Returns zero if valid headers found and parsed; non-zero otherwise |
| 1399 | */ |
Michael Halcrow | d7cdc5f | 2007-10-16 01:28:10 -0700 | [diff] [blame] | 1400 | int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1401 | { |
Tim Gardner | bb45036 | 2012-01-12 16:31:55 +0100 | [diff] [blame] | 1402 | int rc; |
| 1403 | char *page_virt; |
David Howells | 2b0143b | 2015-03-17 22:25:59 +0000 | [diff] [blame] | 1404 | struct inode *ecryptfs_inode = d_inode(ecryptfs_dentry); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1405 | struct ecryptfs_crypt_stat *crypt_stat = |
Michael Halcrow | d7cdc5f | 2007-10-16 01:28:10 -0700 | [diff] [blame] | 1406 | &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat; |
Michael Halcrow | e77a56d | 2007-02-12 00:53:47 -0800 | [diff] [blame] | 1407 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat = |
| 1408 | &ecryptfs_superblock_to_private( |
| 1409 | ecryptfs_dentry->d_sb)->mount_crypt_stat; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1410 | |
Michael Halcrow | e77a56d | 2007-02-12 00:53:47 -0800 | [diff] [blame] | 1411 | ecryptfs_copy_mount_wide_flags_to_inode_flags(crypt_stat, |
| 1412 | mount_crypt_stat); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1413 | /* Read the first page from the underlying file */ |
Tyler Hicks | 3063287 | 2011-05-24 05:11:12 -0500 | [diff] [blame] | 1414 | page_virt = kmem_cache_alloc(ecryptfs_header_cache, GFP_USER); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1415 | if (!page_virt) { |
| 1416 | rc = -ENOMEM; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1417 | goto out; |
| 1418 | } |
Michael Halcrow | d7cdc5f | 2007-10-16 01:28:10 -0700 | [diff] [blame] | 1419 | rc = ecryptfs_read_lower(page_virt, 0, crypt_stat->extent_size, |
| 1420 | ecryptfs_inode); |
Tyler Hicks | 96a7b9c | 2009-09-16 19:04:20 -0500 | [diff] [blame] | 1421 | if (rc >= 0) |
Michael Halcrow | d7cdc5f | 2007-10-16 01:28:10 -0700 | [diff] [blame] | 1422 | rc = ecryptfs_read_headers_virt(page_virt, crypt_stat, |
| 1423 | ecryptfs_dentry, |
| 1424 | ECRYPTFS_VALIDATE_HEADER_SIZE); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1425 | if (rc) { |
Tim Gardner | bb45036 | 2012-01-12 16:31:55 +0100 | [diff] [blame] | 1426 | /* metadata is not in the file header, so try xattrs */ |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 1427 | memset(page_virt, 0, PAGE_SIZE); |
Michael Halcrow | d7cdc5f | 2007-10-16 01:28:10 -0700 | [diff] [blame] | 1428 | rc = ecryptfs_read_xattr_region(page_virt, ecryptfs_inode); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1429 | if (rc) { |
| 1430 | printk(KERN_DEBUG "Valid eCryptfs headers not found in " |
Tim Gardner | 30373dc | 2012-01-12 16:31:55 +0100 | [diff] [blame] | 1431 | "file header region or xattr region, inode %lu\n", |
| 1432 | ecryptfs_inode->i_ino); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1433 | rc = -EINVAL; |
| 1434 | goto out; |
| 1435 | } |
| 1436 | rc = ecryptfs_read_headers_virt(page_virt, crypt_stat, |
| 1437 | ecryptfs_dentry, |
| 1438 | ECRYPTFS_DONT_VALIDATE_HEADER_SIZE); |
| 1439 | if (rc) { |
| 1440 | printk(KERN_DEBUG "Valid eCryptfs headers not found in " |
Tim Gardner | 30373dc | 2012-01-12 16:31:55 +0100 | [diff] [blame] | 1441 | "file xattr region either, inode %lu\n", |
| 1442 | ecryptfs_inode->i_ino); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1443 | rc = -EINVAL; |
| 1444 | } |
| 1445 | if (crypt_stat->mount_crypt_stat->flags |
| 1446 | & ECRYPTFS_XATTR_METADATA_ENABLED) { |
| 1447 | crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR; |
| 1448 | } else { |
| 1449 | printk(KERN_WARNING "Attempt to access file with " |
| 1450 | "crypto metadata only in the extended attribute " |
| 1451 | "region, but eCryptfs was mounted without " |
| 1452 | "xattr support enabled. eCryptfs will not treat " |
Tim Gardner | 30373dc | 2012-01-12 16:31:55 +0100 | [diff] [blame] | 1453 | "this like an encrypted file, inode %lu\n", |
| 1454 | ecryptfs_inode->i_ino); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1455 | rc = -EINVAL; |
| 1456 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1457 | } |
| 1458 | out: |
| 1459 | if (page_virt) { |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 1460 | memset(page_virt, 0, PAGE_SIZE); |
Tyler Hicks | 3063287 | 2011-05-24 05:11:12 -0500 | [diff] [blame] | 1461 | kmem_cache_free(ecryptfs_header_cache, page_virt); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1462 | } |
| 1463 | return rc; |
| 1464 | } |
| 1465 | |
| 1466 | /** |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1467 | * ecryptfs_encrypt_filename - encrypt filename |
| 1468 | * |
| 1469 | * CBC-encrypts the filename. We do not want to encrypt the same |
| 1470 | * filename with the same key and IV, which may happen with hard |
| 1471 | * links, so we prepend random bits to each filename. |
| 1472 | * |
| 1473 | * Returns zero on success; non-zero otherwise |
| 1474 | */ |
| 1475 | static int |
| 1476 | ecryptfs_encrypt_filename(struct ecryptfs_filename *filename, |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1477 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat) |
| 1478 | { |
| 1479 | int rc = 0; |
| 1480 | |
| 1481 | filename->encrypted_filename = NULL; |
| 1482 | filename->encrypted_filename_size = 0; |
Al Viro | 97c3160 | 2016-02-22 18:14:25 -0500 | [diff] [blame] | 1483 | if (mount_crypt_stat && (mount_crypt_stat->flags |
| 1484 | & ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK)) { |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1485 | size_t packet_size; |
| 1486 | size_t remaining_bytes; |
| 1487 | |
| 1488 | rc = ecryptfs_write_tag_70_packet( |
| 1489 | NULL, NULL, |
| 1490 | &filename->encrypted_filename_size, |
| 1491 | mount_crypt_stat, NULL, |
| 1492 | filename->filename_size); |
| 1493 | if (rc) { |
| 1494 | printk(KERN_ERR "%s: Error attempting to get packet " |
| 1495 | "size for tag 72; rc = [%d]\n", __func__, |
| 1496 | rc); |
| 1497 | filename->encrypted_filename_size = 0; |
| 1498 | goto out; |
| 1499 | } |
| 1500 | filename->encrypted_filename = |
| 1501 | kmalloc(filename->encrypted_filename_size, GFP_KERNEL); |
| 1502 | if (!filename->encrypted_filename) { |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1503 | rc = -ENOMEM; |
| 1504 | goto out; |
| 1505 | } |
| 1506 | remaining_bytes = filename->encrypted_filename_size; |
| 1507 | rc = ecryptfs_write_tag_70_packet(filename->encrypted_filename, |
| 1508 | &remaining_bytes, |
| 1509 | &packet_size, |
| 1510 | mount_crypt_stat, |
| 1511 | filename->filename, |
| 1512 | filename->filename_size); |
| 1513 | if (rc) { |
| 1514 | printk(KERN_ERR "%s: Error attempting to generate " |
| 1515 | "tag 70 packet; rc = [%d]\n", __func__, |
| 1516 | rc); |
| 1517 | kfree(filename->encrypted_filename); |
| 1518 | filename->encrypted_filename = NULL; |
| 1519 | filename->encrypted_filename_size = 0; |
| 1520 | goto out; |
| 1521 | } |
| 1522 | filename->encrypted_filename_size = packet_size; |
| 1523 | } else { |
| 1524 | printk(KERN_ERR "%s: No support for requested filename " |
| 1525 | "encryption method in this release\n", __func__); |
Tyler Hicks | df6ad33 | 2009-08-21 04:27:46 -0500 | [diff] [blame] | 1526 | rc = -EOPNOTSUPP; |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1527 | goto out; |
| 1528 | } |
| 1529 | out: |
| 1530 | return rc; |
| 1531 | } |
| 1532 | |
| 1533 | static int ecryptfs_copy_filename(char **copied_name, size_t *copied_name_size, |
| 1534 | const char *name, size_t name_size) |
| 1535 | { |
| 1536 | int rc = 0; |
| 1537 | |
Tyler Hicks | fd9fc84 | 2009-02-06 18:06:51 -0600 | [diff] [blame] | 1538 | (*copied_name) = kmalloc((name_size + 1), GFP_KERNEL); |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1539 | if (!(*copied_name)) { |
| 1540 | rc = -ENOMEM; |
| 1541 | goto out; |
| 1542 | } |
| 1543 | memcpy((void *)(*copied_name), (void *)name, name_size); |
| 1544 | (*copied_name)[(name_size)] = '\0'; /* Only for convenience |
| 1545 | * in printing out the |
| 1546 | * string in debug |
| 1547 | * messages */ |
Tyler Hicks | fd9fc84 | 2009-02-06 18:06:51 -0600 | [diff] [blame] | 1548 | (*copied_name_size) = name_size; |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1549 | out: |
| 1550 | return rc; |
| 1551 | } |
| 1552 | |
| 1553 | /** |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1554 | * ecryptfs_process_key_cipher - Perform key cipher initialization. |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1555 | * @key_tfm: Crypto context for key material, set by this function |
Michael Halcrow | e5d9cbd | 2006-10-30 22:07:16 -0800 | [diff] [blame] | 1556 | * @cipher_name: Name of the cipher |
| 1557 | * @key_size: Size of the key in bytes |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1558 | * |
| 1559 | * Returns zero on success. Any crypto_tfm structs allocated here |
| 1560 | * should be released by other functions, such as on a superblock put |
| 1561 | * event, regardless of whether this function succeeds for fails. |
| 1562 | */ |
Michael Halcrow | cd9d67d | 2007-10-16 01:28:04 -0700 | [diff] [blame] | 1563 | static int |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1564 | ecryptfs_process_key_cipher(struct crypto_skcipher **key_tfm, |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1565 | char *cipher_name, size_t *key_size) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1566 | { |
| 1567 | char dummy_key[ECRYPTFS_MAX_KEY_BYTES]; |
Dan Carpenter | ece550f | 2010-01-19 12:34:32 +0300 | [diff] [blame] | 1568 | char *full_alg_name = NULL; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1569 | int rc; |
| 1570 | |
Michael Halcrow | e5d9cbd | 2006-10-30 22:07:16 -0800 | [diff] [blame] | 1571 | *key_tfm = NULL; |
| 1572 | if (*key_size > ECRYPTFS_MAX_KEY_BYTES) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1573 | rc = -EINVAL; |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 1574 | printk(KERN_ERR "Requested key size is [%zd] bytes; maximum " |
Michael Halcrow | e5d9cbd | 2006-10-30 22:07:16 -0800 | [diff] [blame] | 1575 | "allowable is [%d]\n", *key_size, ECRYPTFS_MAX_KEY_BYTES); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1576 | goto out; |
| 1577 | } |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 1578 | rc = ecryptfs_crypto_api_algify_cipher_name(&full_alg_name, cipher_name, |
| 1579 | "ecb"); |
| 1580 | if (rc) |
| 1581 | goto out; |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1582 | *key_tfm = crypto_alloc_skcipher(full_alg_name, 0, CRYPTO_ALG_ASYNC); |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 1583 | if (IS_ERR(*key_tfm)) { |
| 1584 | rc = PTR_ERR(*key_tfm); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1585 | printk(KERN_ERR "Unable to allocate crypto cipher with name " |
Dave Hansen | 3826849 | 2009-08-27 09:47:07 -0700 | [diff] [blame] | 1586 | "[%s]; rc = [%d]\n", full_alg_name, rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1587 | goto out; |
| 1588 | } |
Eric Biggers | 231baec | 2019-01-18 22:48:00 -0800 | [diff] [blame] | 1589 | crypto_skcipher_set_flags(*key_tfm, CRYPTO_TFM_REQ_FORBID_WEAK_KEYS); |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1590 | if (*key_size == 0) |
Eric Biggers | 9ac0d13 | 2019-11-29 10:23:04 -0800 | [diff] [blame] | 1591 | *key_size = crypto_skcipher_max_keysize(*key_tfm); |
Michael Halcrow | e5d9cbd | 2006-10-30 22:07:16 -0800 | [diff] [blame] | 1592 | get_random_bytes(dummy_key, *key_size); |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1593 | rc = crypto_skcipher_setkey(*key_tfm, dummy_key, *key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1594 | if (rc) { |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 1595 | printk(KERN_ERR "Error attempting to set key of size [%zd] for " |
Dave Hansen | 3826849 | 2009-08-27 09:47:07 -0700 | [diff] [blame] | 1596 | "cipher [%s]; rc = [%d]\n", *key_size, full_alg_name, |
| 1597 | rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1598 | rc = -EINVAL; |
| 1599 | goto out; |
| 1600 | } |
| 1601 | out: |
Dan Carpenter | ece550f | 2010-01-19 12:34:32 +0300 | [diff] [blame] | 1602 | kfree(full_alg_name); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1603 | return rc; |
| 1604 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1605 | |
| 1606 | struct kmem_cache *ecryptfs_key_tfm_cache; |
Adrian Bunk | 7896b63 | 2008-02-06 01:38:32 -0800 | [diff] [blame] | 1607 | static struct list_head key_tfm_list; |
Eric Sandeen | af440f5 | 2008-02-06 01:38:37 -0800 | [diff] [blame] | 1608 | struct mutex key_tfm_list_mutex; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1609 | |
Jerome Marchand | 7371a38 | 2010-08-17 17:24:05 +0200 | [diff] [blame] | 1610 | int __init ecryptfs_init_crypto(void) |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1611 | { |
| 1612 | mutex_init(&key_tfm_list_mutex); |
| 1613 | INIT_LIST_HEAD(&key_tfm_list); |
| 1614 | return 0; |
| 1615 | } |
| 1616 | |
Eric Sandeen | af440f5 | 2008-02-06 01:38:37 -0800 | [diff] [blame] | 1617 | /** |
| 1618 | * ecryptfs_destroy_crypto - free all cached key_tfms on key_tfm_list |
| 1619 | * |
| 1620 | * Called only at module unload time |
| 1621 | */ |
Michael Halcrow | fcd1283 | 2007-10-16 01:28:01 -0700 | [diff] [blame] | 1622 | int ecryptfs_destroy_crypto(void) |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1623 | { |
| 1624 | struct ecryptfs_key_tfm *key_tfm, *key_tfm_tmp; |
| 1625 | |
| 1626 | mutex_lock(&key_tfm_list_mutex); |
| 1627 | list_for_each_entry_safe(key_tfm, key_tfm_tmp, &key_tfm_list, |
| 1628 | key_tfm_list) { |
| 1629 | list_del(&key_tfm->key_tfm_list); |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1630 | crypto_free_skcipher(key_tfm->key_tfm); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1631 | kmem_cache_free(ecryptfs_key_tfm_cache, key_tfm); |
| 1632 | } |
| 1633 | mutex_unlock(&key_tfm_list_mutex); |
| 1634 | return 0; |
| 1635 | } |
| 1636 | |
| 1637 | int |
| 1638 | ecryptfs_add_new_key_tfm(struct ecryptfs_key_tfm **key_tfm, char *cipher_name, |
| 1639 | size_t key_size) |
| 1640 | { |
| 1641 | struct ecryptfs_key_tfm *tmp_tfm; |
| 1642 | int rc = 0; |
| 1643 | |
Eric Sandeen | af440f5 | 2008-02-06 01:38:37 -0800 | [diff] [blame] | 1644 | BUG_ON(!mutex_is_locked(&key_tfm_list_mutex)); |
| 1645 | |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1646 | tmp_tfm = kmem_cache_alloc(ecryptfs_key_tfm_cache, GFP_KERNEL); |
Markus Elfring | 5032f36 | 2017-08-19 18:00:22 +0200 | [diff] [blame] | 1647 | if (key_tfm) |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1648 | (*key_tfm) = tmp_tfm; |
| 1649 | if (!tmp_tfm) { |
| 1650 | rc = -ENOMEM; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1651 | goto out; |
| 1652 | } |
| 1653 | mutex_init(&tmp_tfm->key_tfm_mutex); |
| 1654 | strncpy(tmp_tfm->cipher_name, cipher_name, |
| 1655 | ECRYPTFS_MAX_CIPHER_NAME_SIZE); |
Eric Sandeen | b886290 | 2007-12-22 14:03:24 -0800 | [diff] [blame] | 1656 | tmp_tfm->cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE] = '\0'; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1657 | tmp_tfm->key_size = key_size; |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1658 | rc = ecryptfs_process_key_cipher(&tmp_tfm->key_tfm, |
| 1659 | tmp_tfm->cipher_name, |
| 1660 | &tmp_tfm->key_size); |
| 1661 | if (rc) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1662 | printk(KERN_ERR "Error attempting to initialize key TFM " |
| 1663 | "cipher with name = [%s]; rc = [%d]\n", |
| 1664 | tmp_tfm->cipher_name, rc); |
| 1665 | kmem_cache_free(ecryptfs_key_tfm_cache, tmp_tfm); |
Markus Elfring | 5032f36 | 2017-08-19 18:00:22 +0200 | [diff] [blame] | 1666 | if (key_tfm) |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1667 | (*key_tfm) = NULL; |
| 1668 | goto out; |
| 1669 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1670 | list_add(&tmp_tfm->key_tfm_list, &key_tfm_list); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1671 | out: |
| 1672 | return rc; |
| 1673 | } |
| 1674 | |
Eric Sandeen | af440f5 | 2008-02-06 01:38:37 -0800 | [diff] [blame] | 1675 | /** |
| 1676 | * ecryptfs_tfm_exists - Search for existing tfm for cipher_name. |
| 1677 | * @cipher_name: the name of the cipher to search for |
| 1678 | * @key_tfm: set to corresponding tfm if found |
| 1679 | * |
| 1680 | * Searches for cached key_tfm matching @cipher_name |
| 1681 | * Must be called with &key_tfm_list_mutex held |
| 1682 | * Returns 1 if found, with @key_tfm set |
| 1683 | * Returns 0 if not found, with @key_tfm set to NULL |
| 1684 | */ |
| 1685 | int ecryptfs_tfm_exists(char *cipher_name, struct ecryptfs_key_tfm **key_tfm) |
| 1686 | { |
| 1687 | struct ecryptfs_key_tfm *tmp_key_tfm; |
| 1688 | |
| 1689 | BUG_ON(!mutex_is_locked(&key_tfm_list_mutex)); |
| 1690 | |
| 1691 | list_for_each_entry(tmp_key_tfm, &key_tfm_list, key_tfm_list) { |
| 1692 | if (strcmp(tmp_key_tfm->cipher_name, cipher_name) == 0) { |
| 1693 | if (key_tfm) |
| 1694 | (*key_tfm) = tmp_key_tfm; |
| 1695 | return 1; |
| 1696 | } |
| 1697 | } |
| 1698 | if (key_tfm) |
| 1699 | (*key_tfm) = NULL; |
| 1700 | return 0; |
| 1701 | } |
| 1702 | |
| 1703 | /** |
| 1704 | * ecryptfs_get_tfm_and_mutex_for_cipher_name |
| 1705 | * |
| 1706 | * @tfm: set to cached tfm found, or new tfm created |
| 1707 | * @tfm_mutex: set to mutex for cached tfm found, or new tfm created |
| 1708 | * @cipher_name: the name of the cipher to search for and/or add |
| 1709 | * |
| 1710 | * Sets pointers to @tfm & @tfm_mutex matching @cipher_name. |
| 1711 | * Searches for cached item first, and creates new if not found. |
| 1712 | * Returns 0 on success, non-zero if adding new cipher failed |
| 1713 | */ |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 1714 | int ecryptfs_get_tfm_and_mutex_for_cipher_name(struct crypto_skcipher **tfm, |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1715 | struct mutex **tfm_mutex, |
| 1716 | char *cipher_name) |
| 1717 | { |
| 1718 | struct ecryptfs_key_tfm *key_tfm; |
| 1719 | int rc = 0; |
| 1720 | |
| 1721 | (*tfm) = NULL; |
| 1722 | (*tfm_mutex) = NULL; |
Eric Sandeen | af440f5 | 2008-02-06 01:38:37 -0800 | [diff] [blame] | 1723 | |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1724 | mutex_lock(&key_tfm_list_mutex); |
Eric Sandeen | af440f5 | 2008-02-06 01:38:37 -0800 | [diff] [blame] | 1725 | if (!ecryptfs_tfm_exists(cipher_name, &key_tfm)) { |
| 1726 | rc = ecryptfs_add_new_key_tfm(&key_tfm, cipher_name, 0); |
| 1727 | if (rc) { |
| 1728 | printk(KERN_ERR "Error adding new key_tfm to list; " |
| 1729 | "rc = [%d]\n", rc); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1730 | goto out; |
| 1731 | } |
| 1732 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1733 | (*tfm) = key_tfm->key_tfm; |
| 1734 | (*tfm_mutex) = &key_tfm->key_tfm_mutex; |
| 1735 | out: |
Cyrill Gorcunov | 71fd517 | 2008-05-23 13:04:20 -0700 | [diff] [blame] | 1736 | mutex_unlock(&key_tfm_list_mutex); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1737 | return rc; |
| 1738 | } |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1739 | |
| 1740 | /* 64 characters forming a 6-bit target field */ |
| 1741 | static unsigned char *portable_filename_chars = ("-.0123456789ABCD" |
| 1742 | "EFGHIJKLMNOPQRST" |
| 1743 | "UVWXYZabcdefghij" |
| 1744 | "klmnopqrstuvwxyz"); |
| 1745 | |
| 1746 | /* We could either offset on every reverse map or just pad some 0x00's |
| 1747 | * at the front here */ |
Tyler Hicks | 0f751e6 | 2011-11-23 11:31:24 -0600 | [diff] [blame] | 1748 | static const unsigned char filename_rev_map[256] = { |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1749 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 7 */ |
| 1750 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 15 */ |
| 1751 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 23 */ |
| 1752 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 31 */ |
| 1753 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 39 */ |
| 1754 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, /* 47 */ |
| 1755 | 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, /* 55 */ |
| 1756 | 0x0A, 0x0B, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 63 */ |
| 1757 | 0x00, 0x0C, 0x0D, 0x0E, 0x0F, 0x10, 0x11, 0x12, /* 71 */ |
| 1758 | 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A, /* 79 */ |
| 1759 | 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 0x21, 0x22, /* 87 */ |
| 1760 | 0x23, 0x24, 0x25, 0x00, 0x00, 0x00, 0x00, 0x00, /* 95 */ |
| 1761 | 0x00, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, /* 103 */ |
| 1762 | 0x2D, 0x2E, 0x2F, 0x30, 0x31, 0x32, 0x33, 0x34, /* 111 */ |
| 1763 | 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C, /* 119 */ |
Tyler Hicks | 0f751e6 | 2011-11-23 11:31:24 -0600 | [diff] [blame] | 1764 | 0x3D, 0x3E, 0x3F /* 123 - 255 initialized to 0x00 */ |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1765 | }; |
| 1766 | |
| 1767 | /** |
| 1768 | * ecryptfs_encode_for_filename |
| 1769 | * @dst: Destination location for encoded filename |
| 1770 | * @dst_size: Size of the encoded filename in bytes |
| 1771 | * @src: Source location for the filename to encode |
| 1772 | * @src_size: Size of the source in bytes |
| 1773 | */ |
Cong Ding | 3702875 | 2012-12-07 22:21:56 +0000 | [diff] [blame] | 1774 | static void ecryptfs_encode_for_filename(unsigned char *dst, size_t *dst_size, |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1775 | unsigned char *src, size_t src_size) |
| 1776 | { |
| 1777 | size_t num_blocks; |
| 1778 | size_t block_num = 0; |
| 1779 | size_t dst_offset = 0; |
| 1780 | unsigned char last_block[3]; |
| 1781 | |
| 1782 | if (src_size == 0) { |
| 1783 | (*dst_size) = 0; |
| 1784 | goto out; |
| 1785 | } |
| 1786 | num_blocks = (src_size / 3); |
| 1787 | if ((src_size % 3) == 0) { |
| 1788 | memcpy(last_block, (&src[src_size - 3]), 3); |
| 1789 | } else { |
| 1790 | num_blocks++; |
| 1791 | last_block[2] = 0x00; |
| 1792 | switch (src_size % 3) { |
| 1793 | case 1: |
| 1794 | last_block[0] = src[src_size - 1]; |
| 1795 | last_block[1] = 0x00; |
| 1796 | break; |
| 1797 | case 2: |
| 1798 | last_block[0] = src[src_size - 2]; |
| 1799 | last_block[1] = src[src_size - 1]; |
| 1800 | } |
| 1801 | } |
| 1802 | (*dst_size) = (num_blocks * 4); |
| 1803 | if (!dst) |
| 1804 | goto out; |
| 1805 | while (block_num < num_blocks) { |
| 1806 | unsigned char *src_block; |
| 1807 | unsigned char dst_block[4]; |
| 1808 | |
| 1809 | if (block_num == (num_blocks - 1)) |
| 1810 | src_block = last_block; |
| 1811 | else |
| 1812 | src_block = &src[block_num * 3]; |
| 1813 | dst_block[0] = ((src_block[0] >> 2) & 0x3F); |
| 1814 | dst_block[1] = (((src_block[0] << 4) & 0x30) |
| 1815 | | ((src_block[1] >> 4) & 0x0F)); |
| 1816 | dst_block[2] = (((src_block[1] << 2) & 0x3C) |
| 1817 | | ((src_block[2] >> 6) & 0x03)); |
| 1818 | dst_block[3] = (src_block[2] & 0x3F); |
| 1819 | dst[dst_offset++] = portable_filename_chars[dst_block[0]]; |
| 1820 | dst[dst_offset++] = portable_filename_chars[dst_block[1]]; |
| 1821 | dst[dst_offset++] = portable_filename_chars[dst_block[2]]; |
| 1822 | dst[dst_offset++] = portable_filename_chars[dst_block[3]]; |
| 1823 | block_num++; |
| 1824 | } |
| 1825 | out: |
| 1826 | return; |
| 1827 | } |
| 1828 | |
Tyler Hicks | 4a26620 | 2011-11-05 13:45:08 -0400 | [diff] [blame] | 1829 | static size_t ecryptfs_max_decoded_size(size_t encoded_size) |
| 1830 | { |
| 1831 | /* Not exact; conservatively long. Every block of 4 |
| 1832 | * encoded characters decodes into a block of 3 |
| 1833 | * decoded characters. This segment of code provides |
| 1834 | * the caller with the maximum amount of allocated |
| 1835 | * space that @dst will need to point to in a |
| 1836 | * subsequent call. */ |
| 1837 | return ((encoded_size + 1) * 3) / 4; |
| 1838 | } |
| 1839 | |
Michael Halcrow | 71c11c3 | 2009-01-06 14:42:05 -0800 | [diff] [blame] | 1840 | /** |
| 1841 | * ecryptfs_decode_from_filename |
| 1842 | * @dst: If NULL, this function only sets @dst_size and returns. If |
| 1843 | * non-NULL, this function decodes the encoded octets in @src |
| 1844 | * into the memory that @dst points to. |
| 1845 | * @dst_size: Set to the size of the decoded string. |
| 1846 | * @src: The encoded set of octets to decode. |
| 1847 | * @src_size: The size of the encoded set of octets to decode. |
| 1848 | */ |
| 1849 | static void |
| 1850 | ecryptfs_decode_from_filename(unsigned char *dst, size_t *dst_size, |
| 1851 | const unsigned char *src, size_t src_size) |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1852 | { |
| 1853 | u8 current_bit_offset = 0; |
| 1854 | size_t src_byte_offset = 0; |
| 1855 | size_t dst_byte_offset = 0; |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1856 | |
Markus Elfring | 5032f36 | 2017-08-19 18:00:22 +0200 | [diff] [blame] | 1857 | if (!dst) { |
Tyler Hicks | 4a26620 | 2011-11-05 13:45:08 -0400 | [diff] [blame] | 1858 | (*dst_size) = ecryptfs_max_decoded_size(src_size); |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1859 | goto out; |
| 1860 | } |
| 1861 | while (src_byte_offset < src_size) { |
| 1862 | unsigned char src_byte = |
| 1863 | filename_rev_map[(int)src[src_byte_offset]]; |
| 1864 | |
| 1865 | switch (current_bit_offset) { |
| 1866 | case 0: |
| 1867 | dst[dst_byte_offset] = (src_byte << 2); |
| 1868 | current_bit_offset = 6; |
| 1869 | break; |
| 1870 | case 6: |
| 1871 | dst[dst_byte_offset++] |= (src_byte >> 4); |
| 1872 | dst[dst_byte_offset] = ((src_byte & 0xF) |
| 1873 | << 4); |
| 1874 | current_bit_offset = 4; |
| 1875 | break; |
| 1876 | case 4: |
| 1877 | dst[dst_byte_offset++] |= (src_byte >> 2); |
| 1878 | dst[dst_byte_offset] = (src_byte << 6); |
| 1879 | current_bit_offset = 2; |
| 1880 | break; |
| 1881 | case 2: |
| 1882 | dst[dst_byte_offset++] |= (src_byte); |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1883 | current_bit_offset = 0; |
| 1884 | break; |
| 1885 | } |
| 1886 | src_byte_offset++; |
| 1887 | } |
| 1888 | (*dst_size) = dst_byte_offset; |
| 1889 | out: |
Michael Halcrow | 71c11c3 | 2009-01-06 14:42:05 -0800 | [diff] [blame] | 1890 | return; |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1891 | } |
| 1892 | |
| 1893 | /** |
| 1894 | * ecryptfs_encrypt_and_encode_filename - converts a plaintext file name to cipher text |
| 1895 | * @crypt_stat: The crypt_stat struct associated with the file anem to encode |
| 1896 | * @name: The plaintext name |
| 1897 | * @length: The length of the plaintext |
| 1898 | * @encoded_name: The encypted name |
| 1899 | * |
| 1900 | * Encrypts and encodes a filename into something that constitutes a |
| 1901 | * valid filename for a filesystem, with printable characters. |
| 1902 | * |
| 1903 | * We assume that we have a properly initialized crypto context, |
| 1904 | * pointed to by crypt_stat->tfm. |
| 1905 | * |
| 1906 | * Returns zero on success; non-zero on otherwise |
| 1907 | */ |
| 1908 | int ecryptfs_encrypt_and_encode_filename( |
| 1909 | char **encoded_name, |
| 1910 | size_t *encoded_name_size, |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1911 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat, |
| 1912 | const char *name, size_t name_size) |
| 1913 | { |
| 1914 | size_t encoded_name_no_prefix_size; |
| 1915 | int rc = 0; |
| 1916 | |
| 1917 | (*encoded_name) = NULL; |
| 1918 | (*encoded_name_size) = 0; |
Al Viro | 97c3160 | 2016-02-22 18:14:25 -0500 | [diff] [blame] | 1919 | if (mount_crypt_stat && (mount_crypt_stat->flags |
| 1920 | & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)) { |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1921 | struct ecryptfs_filename *filename; |
| 1922 | |
| 1923 | filename = kzalloc(sizeof(*filename), GFP_KERNEL); |
| 1924 | if (!filename) { |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1925 | rc = -ENOMEM; |
| 1926 | goto out; |
| 1927 | } |
| 1928 | filename->filename = (char *)name; |
| 1929 | filename->filename_size = name_size; |
Al Viro | 97c3160 | 2016-02-22 18:14:25 -0500 | [diff] [blame] | 1930 | rc = ecryptfs_encrypt_filename(filename, mount_crypt_stat); |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1931 | if (rc) { |
| 1932 | printk(KERN_ERR "%s: Error attempting to encrypt " |
| 1933 | "filename; rc = [%d]\n", __func__, rc); |
| 1934 | kfree(filename); |
| 1935 | goto out; |
| 1936 | } |
| 1937 | ecryptfs_encode_for_filename( |
| 1938 | NULL, &encoded_name_no_prefix_size, |
| 1939 | filename->encrypted_filename, |
| 1940 | filename->encrypted_filename_size); |
Al Viro | 97c3160 | 2016-02-22 18:14:25 -0500 | [diff] [blame] | 1941 | if (mount_crypt_stat |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1942 | && (mount_crypt_stat->flags |
Al Viro | 97c3160 | 2016-02-22 18:14:25 -0500 | [diff] [blame] | 1943 | & ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK)) |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1944 | (*encoded_name_size) = |
| 1945 | (ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE |
| 1946 | + encoded_name_no_prefix_size); |
| 1947 | else |
| 1948 | (*encoded_name_size) = |
| 1949 | (ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX_SIZE |
| 1950 | + encoded_name_no_prefix_size); |
| 1951 | (*encoded_name) = kmalloc((*encoded_name_size) + 1, GFP_KERNEL); |
| 1952 | if (!(*encoded_name)) { |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1953 | rc = -ENOMEM; |
| 1954 | kfree(filename->encrypted_filename); |
| 1955 | kfree(filename); |
| 1956 | goto out; |
| 1957 | } |
Al Viro | 97c3160 | 2016-02-22 18:14:25 -0500 | [diff] [blame] | 1958 | if (mount_crypt_stat |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1959 | && (mount_crypt_stat->flags |
Al Viro | 97c3160 | 2016-02-22 18:14:25 -0500 | [diff] [blame] | 1960 | & ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK)) { |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1961 | memcpy((*encoded_name), |
| 1962 | ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX, |
| 1963 | ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE); |
| 1964 | ecryptfs_encode_for_filename( |
| 1965 | ((*encoded_name) |
| 1966 | + ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE), |
| 1967 | &encoded_name_no_prefix_size, |
| 1968 | filename->encrypted_filename, |
| 1969 | filename->encrypted_filename_size); |
| 1970 | (*encoded_name_size) = |
| 1971 | (ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE |
| 1972 | + encoded_name_no_prefix_size); |
| 1973 | (*encoded_name)[(*encoded_name_size)] = '\0'; |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1974 | } else { |
Tyler Hicks | df6ad33 | 2009-08-21 04:27:46 -0500 | [diff] [blame] | 1975 | rc = -EOPNOTSUPP; |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 1976 | } |
| 1977 | if (rc) { |
| 1978 | printk(KERN_ERR "%s: Error attempting to encode " |
| 1979 | "encrypted filename; rc = [%d]\n", __func__, |
| 1980 | rc); |
| 1981 | kfree((*encoded_name)); |
| 1982 | (*encoded_name) = NULL; |
| 1983 | (*encoded_name_size) = 0; |
| 1984 | } |
| 1985 | kfree(filename->encrypted_filename); |
| 1986 | kfree(filename); |
| 1987 | } else { |
| 1988 | rc = ecryptfs_copy_filename(encoded_name, |
| 1989 | encoded_name_size, |
| 1990 | name, name_size); |
| 1991 | } |
| 1992 | out: |
| 1993 | return rc; |
| 1994 | } |
| 1995 | |
Tyler Hicks | e86281e | 2018-03-28 23:41:52 +0000 | [diff] [blame] | 1996 | static bool is_dot_dotdot(const char *name, size_t name_size) |
| 1997 | { |
| 1998 | if (name_size == 1 && name[0] == '.') |
| 1999 | return true; |
| 2000 | else if (name_size == 2 && name[0] == '.' && name[1] == '.') |
| 2001 | return true; |
| 2002 | |
| 2003 | return false; |
| 2004 | } |
| 2005 | |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 2006 | /** |
| 2007 | * ecryptfs_decode_and_decrypt_filename - converts the encoded cipher text name to decoded plaintext |
| 2008 | * @plaintext_name: The plaintext name |
| 2009 | * @plaintext_name_size: The plaintext name size |
| 2010 | * @ecryptfs_dir_dentry: eCryptfs directory dentry |
| 2011 | * @name: The filename in cipher text |
| 2012 | * @name_size: The cipher text name size |
| 2013 | * |
| 2014 | * Decrypts and decodes the filename. |
| 2015 | * |
| 2016 | * Returns zero on error; non-zero otherwise |
| 2017 | */ |
| 2018 | int ecryptfs_decode_and_decrypt_filename(char **plaintext_name, |
| 2019 | size_t *plaintext_name_size, |
Al Viro | 0747fdb | 2013-06-16 20:05:38 +0400 | [diff] [blame] | 2020 | struct super_block *sb, |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 2021 | const char *name, size_t name_size) |
| 2022 | { |
Tyler Hicks | 2aac0cf8 | 2009-03-20 02:23:57 -0500 | [diff] [blame] | 2023 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat = |
Al Viro | 0747fdb | 2013-06-16 20:05:38 +0400 | [diff] [blame] | 2024 | &ecryptfs_superblock_to_private(sb)->mount_crypt_stat; |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 2025 | char *decoded_name; |
| 2026 | size_t decoded_name_size; |
| 2027 | size_t packet_size; |
| 2028 | int rc = 0; |
| 2029 | |
Tyler Hicks | e86281e | 2018-03-28 23:41:52 +0000 | [diff] [blame] | 2030 | if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) && |
| 2031 | !(mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)) { |
| 2032 | if (is_dot_dotdot(name, name_size)) { |
| 2033 | rc = ecryptfs_copy_filename(plaintext_name, |
| 2034 | plaintext_name_size, |
| 2035 | name, name_size); |
| 2036 | goto out; |
| 2037 | } |
| 2038 | |
| 2039 | if (name_size <= ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE || |
| 2040 | strncmp(name, ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX, |
| 2041 | ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE)) { |
| 2042 | rc = -EINVAL; |
| 2043 | goto out; |
| 2044 | } |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 2045 | |
| 2046 | name += ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE; |
| 2047 | name_size -= ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE; |
Michael Halcrow | 71c11c3 | 2009-01-06 14:42:05 -0800 | [diff] [blame] | 2048 | ecryptfs_decode_from_filename(NULL, &decoded_name_size, |
| 2049 | name, name_size); |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 2050 | decoded_name = kmalloc(decoded_name_size, GFP_KERNEL); |
| 2051 | if (!decoded_name) { |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 2052 | rc = -ENOMEM; |
| 2053 | goto out; |
| 2054 | } |
Michael Halcrow | 71c11c3 | 2009-01-06 14:42:05 -0800 | [diff] [blame] | 2055 | ecryptfs_decode_from_filename(decoded_name, &decoded_name_size, |
| 2056 | name, name_size); |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 2057 | rc = ecryptfs_parse_tag_70_packet(plaintext_name, |
| 2058 | plaintext_name_size, |
| 2059 | &packet_size, |
| 2060 | mount_crypt_stat, |
| 2061 | decoded_name, |
| 2062 | decoded_name_size); |
| 2063 | if (rc) { |
Tyler Hicks | e86281e | 2018-03-28 23:41:52 +0000 | [diff] [blame] | 2064 | ecryptfs_printk(KERN_DEBUG, |
| 2065 | "%s: Could not parse tag 70 packet from filename\n", |
| 2066 | __func__); |
Michael Halcrow | 51ca58d | 2009-01-06 14:41:59 -0800 | [diff] [blame] | 2067 | goto out_free; |
| 2068 | } |
| 2069 | } else { |
| 2070 | rc = ecryptfs_copy_filename(plaintext_name, |
| 2071 | plaintext_name_size, |
| 2072 | name, name_size); |
| 2073 | goto out; |
| 2074 | } |
| 2075 | out_free: |
| 2076 | kfree(decoded_name); |
| 2077 | out: |
| 2078 | return rc; |
| 2079 | } |
Tyler Hicks | 4a26620 | 2011-11-05 13:45:08 -0400 | [diff] [blame] | 2080 | |
| 2081 | #define ENC_NAME_MAX_BLOCKLEN_8_OR_16 143 |
| 2082 | |
| 2083 | int ecryptfs_set_f_namelen(long *namelen, long lower_namelen, |
| 2084 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat) |
| 2085 | { |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 2086 | struct crypto_skcipher *tfm; |
Tyler Hicks | 4a26620 | 2011-11-05 13:45:08 -0400 | [diff] [blame] | 2087 | struct mutex *tfm_mutex; |
| 2088 | size_t cipher_blocksize; |
| 2089 | int rc; |
| 2090 | |
| 2091 | if (!(mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)) { |
| 2092 | (*namelen) = lower_namelen; |
| 2093 | return 0; |
| 2094 | } |
| 2095 | |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 2096 | rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(&tfm, &tfm_mutex, |
Tyler Hicks | 4a26620 | 2011-11-05 13:45:08 -0400 | [diff] [blame] | 2097 | mount_crypt_stat->global_default_fn_cipher_name); |
| 2098 | if (unlikely(rc)) { |
| 2099 | (*namelen) = 0; |
| 2100 | return rc; |
| 2101 | } |
| 2102 | |
| 2103 | mutex_lock(tfm_mutex); |
Herbert Xu | 3095e8e | 2016-01-25 10:29:33 +0800 | [diff] [blame] | 2104 | cipher_blocksize = crypto_skcipher_blocksize(tfm); |
Tyler Hicks | 4a26620 | 2011-11-05 13:45:08 -0400 | [diff] [blame] | 2105 | mutex_unlock(tfm_mutex); |
| 2106 | |
| 2107 | /* Return an exact amount for the common cases */ |
| 2108 | if (lower_namelen == NAME_MAX |
| 2109 | && (cipher_blocksize == 8 || cipher_blocksize == 16)) { |
| 2110 | (*namelen) = ENC_NAME_MAX_BLOCKLEN_8_OR_16; |
| 2111 | return 0; |
| 2112 | } |
| 2113 | |
| 2114 | /* Return a safe estimate for the uncommon cases */ |
| 2115 | (*namelen) = lower_namelen; |
| 2116 | (*namelen) -= ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE; |
| 2117 | /* Since this is the max decoded size, subtract 1 "decoded block" len */ |
| 2118 | (*namelen) = ecryptfs_max_decoded_size(*namelen) - 3; |
| 2119 | (*namelen) -= ECRYPTFS_TAG_70_MAX_METADATA_SIZE; |
| 2120 | (*namelen) -= ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES; |
| 2121 | /* Worst case is that the filename is padded nearly a full block size */ |
| 2122 | (*namelen) -= cipher_blocksize - 1; |
| 2123 | |
| 2124 | if ((*namelen) < 0) |
| 2125 | (*namelen) = 0; |
| 2126 | |
| 2127 | return 0; |
| 2128 | } |