Paulo Alcantara | abdb174 | 2022-10-04 18:41:27 -0300 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* |
| 3 | * Copyright (c) 2022 Paulo Alcantara <palcantara@suse.de> |
| 4 | */ |
| 5 | |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 6 | #include <linux/namei.h> |
Paulo Alcantara | abdb174 | 2022-10-04 18:41:27 -0300 | [diff] [blame] | 7 | #include "cifsproto.h" |
| 8 | #include "cifs_debug.h" |
| 9 | #include "dns_resolve.h" |
| 10 | #include "fs_context.h" |
| 11 | #include "dfs.h" |
| 12 | |
Paulo Alcantara | abdb174 | 2022-10-04 18:41:27 -0300 | [diff] [blame] | 13 | /** |
| 14 | * dfs_parse_target_referral - set fs context for dfs target referral |
| 15 | * |
| 16 | * @full_path: full path in UNC format. |
| 17 | * @ref: dfs referral pointer. |
| 18 | * @ctx: smb3 fs context pointer. |
| 19 | * |
| 20 | * Return zero if dfs referral was parsed correctly, otherwise non-zero. |
| 21 | */ |
| 22 | int dfs_parse_target_referral(const char *full_path, const struct dfs_info3_param *ref, |
| 23 | struct smb3_fs_context *ctx) |
| 24 | { |
| 25 | int rc; |
| 26 | const char *prepath = NULL; |
| 27 | char *path; |
| 28 | |
| 29 | if (!full_path || !*full_path || !ref || !ctx) |
| 30 | return -EINVAL; |
| 31 | |
| 32 | if (WARN_ON_ONCE(!ref->node_name || ref->path_consumed < 0)) |
| 33 | return -EINVAL; |
| 34 | |
| 35 | if (strlen(full_path) - ref->path_consumed) { |
| 36 | prepath = full_path + ref->path_consumed; |
| 37 | /* skip initial delimiter */ |
| 38 | if (*prepath == '/' || *prepath == '\\') |
| 39 | prepath++; |
| 40 | } |
| 41 | |
| 42 | path = cifs_build_devname(ref->node_name, prepath); |
| 43 | if (IS_ERR(path)) |
| 44 | return PTR_ERR(path); |
| 45 | |
| 46 | rc = smb3_parse_devname(path, ctx); |
| 47 | if (rc) |
| 48 | goto out; |
| 49 | |
Paulo Alcantara | 6d74016 | 2022-10-04 18:41:36 -0300 | [diff] [blame] | 50 | rc = dns_resolve_server_name_to_ip(path, (struct sockaddr *)&ctx->dstaddr, NULL); |
Paulo Alcantara | abdb174 | 2022-10-04 18:41:27 -0300 | [diff] [blame] | 51 | |
| 52 | out: |
| 53 | kfree(path); |
| 54 | return rc; |
| 55 | } |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 56 | |
| 57 | /* |
| 58 | * cifs_build_path_to_root returns full path to root when we do not have an |
| 59 | * existing connection (tcon) |
| 60 | */ |
| 61 | static char *build_unc_path_to_root(const struct smb3_fs_context *ctx, |
| 62 | const struct cifs_sb_info *cifs_sb, bool useppath) |
| 63 | { |
| 64 | char *full_path, *pos; |
| 65 | unsigned int pplen = useppath && ctx->prepath ? strlen(ctx->prepath) + 1 : 0; |
| 66 | unsigned int unc_len = strnlen(ctx->UNC, MAX_TREE_SIZE + 1); |
| 67 | |
| 68 | if (unc_len > MAX_TREE_SIZE) |
| 69 | return ERR_PTR(-EINVAL); |
| 70 | |
| 71 | full_path = kmalloc(unc_len + pplen + 1, GFP_KERNEL); |
| 72 | if (full_path == NULL) |
| 73 | return ERR_PTR(-ENOMEM); |
| 74 | |
| 75 | memcpy(full_path, ctx->UNC, unc_len); |
| 76 | pos = full_path + unc_len; |
| 77 | |
| 78 | if (pplen) { |
| 79 | *pos = CIFS_DIR_SEP(cifs_sb); |
| 80 | memcpy(pos + 1, ctx->prepath, pplen); |
| 81 | pos += pplen; |
| 82 | } |
| 83 | |
| 84 | *pos = '\0'; /* add trailing null */ |
| 85 | convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb)); |
| 86 | cifs_dbg(FYI, "%s: full_path=%s\n", __func__, full_path); |
| 87 | return full_path; |
| 88 | } |
| 89 | |
| 90 | static int get_session(struct cifs_mount_ctx *mnt_ctx, const char *full_path) |
| 91 | { |
| 92 | struct smb3_fs_context *ctx = mnt_ctx->fs_ctx; |
| 93 | int rc; |
| 94 | |
| 95 | ctx->leaf_fullpath = (char *)full_path; |
| 96 | rc = cifs_mount_get_session(mnt_ctx); |
| 97 | ctx->leaf_fullpath = NULL; |
| 98 | |
| 99 | return rc; |
| 100 | } |
| 101 | |
Paulo Alcantara | 8e35541 | 2023-04-23 23:26:51 -0300 | [diff] [blame] | 102 | static int add_root_smb_session(struct cifs_mount_ctx *mnt_ctx) |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 103 | { |
Paulo Alcantara | b56bce50 | 2023-03-14 20:32:53 -0300 | [diff] [blame] | 104 | struct smb3_fs_context *ctx = mnt_ctx->fs_ctx; |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 105 | struct dfs_root_ses *root_ses; |
Paulo Alcantara | b56bce50 | 2023-03-14 20:32:53 -0300 | [diff] [blame] | 106 | struct cifs_ses *ses = mnt_ctx->ses; |
| 107 | |
| 108 | if (ses) { |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 109 | root_ses = kmalloc(sizeof(*root_ses), GFP_KERNEL); |
| 110 | if (!root_ses) |
| 111 | return -ENOMEM; |
| 112 | |
| 113 | INIT_LIST_HEAD(&root_ses->list); |
| 114 | |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 115 | spin_lock(&cifs_tcp_ses_lock); |
Paulo Alcantara | b56bce50 | 2023-03-14 20:32:53 -0300 | [diff] [blame] | 116 | ses->ses_count++; |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 117 | spin_unlock(&cifs_tcp_ses_lock); |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 118 | root_ses->ses = ses; |
| 119 | list_add_tail(&root_ses->list, &mnt_ctx->dfs_ses_list); |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 120 | } |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 121 | ctx->dfs_root_ses = ses; |
| 122 | return 0; |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 123 | } |
| 124 | |
| 125 | static int get_dfs_conn(struct cifs_mount_ctx *mnt_ctx, const char *ref_path, const char *full_path, |
| 126 | const struct dfs_cache_tgt_iterator *tit) |
| 127 | { |
| 128 | struct smb3_fs_context *ctx = mnt_ctx->fs_ctx; |
| 129 | struct dfs_info3_param ref = {}; |
Paulo Alcantara | 8e35541 | 2023-04-23 23:26:51 -0300 | [diff] [blame] | 130 | bool is_refsrv; |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 131 | int rc, rc2; |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 132 | |
| 133 | rc = dfs_cache_get_tgt_referral(ref_path + 1, tit, &ref); |
| 134 | if (rc) |
| 135 | return rc; |
| 136 | |
| 137 | rc = dfs_parse_target_referral(full_path + 1, &ref, ctx); |
| 138 | if (rc) |
| 139 | goto out; |
| 140 | |
| 141 | cifs_mount_put_conns(mnt_ctx); |
| 142 | rc = get_session(mnt_ctx, ref_path); |
| 143 | if (rc) |
| 144 | goto out; |
| 145 | |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 146 | is_refsrv = !!(ref.flags & DFSREF_REFERRAL_SERVER); |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 147 | |
| 148 | rc = -EREMOTE; |
| 149 | if (ref.flags & DFSREF_STORAGE_SERVER) { |
| 150 | rc = cifs_mount_get_tcon(mnt_ctx); |
| 151 | if (rc) |
| 152 | goto out; |
| 153 | |
| 154 | /* some servers may not advertise referral capability under ref.flags */ |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 155 | is_refsrv |= is_tcon_dfs(mnt_ctx->tcon); |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 156 | |
| 157 | rc = cifs_is_path_remote(mnt_ctx); |
| 158 | } |
| 159 | |
Paulo Alcantara | 6be2ea3 | 2023-04-27 04:40:08 -0300 | [diff] [blame] | 160 | dfs_cache_noreq_update_tgthint(ref_path + 1, tit); |
| 161 | |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 162 | if (rc == -EREMOTE && is_refsrv) { |
Paulo Alcantara | 8e35541 | 2023-04-23 23:26:51 -0300 | [diff] [blame] | 163 | rc2 = add_root_smb_session(mnt_ctx); |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 164 | if (rc2) |
| 165 | rc = rc2; |
| 166 | } |
| 167 | |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 168 | out: |
| 169 | free_dfs_info_param(&ref); |
| 170 | return rc; |
| 171 | } |
| 172 | |
| 173 | static int __dfs_mount_share(struct cifs_mount_ctx *mnt_ctx) |
| 174 | { |
| 175 | struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb; |
| 176 | struct smb3_fs_context *ctx = mnt_ctx->fs_ctx; |
| 177 | char *ref_path = NULL, *full_path = NULL; |
| 178 | struct dfs_cache_tgt_iterator *tit; |
| 179 | struct TCP_Server_Info *server; |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 180 | struct cifs_tcon *tcon; |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 181 | char *origin_fullpath = NULL; |
| 182 | int num_links = 0; |
| 183 | int rc; |
| 184 | |
| 185 | ref_path = dfs_get_path(cifs_sb, ctx->UNC); |
| 186 | if (IS_ERR(ref_path)) |
| 187 | return PTR_ERR(ref_path); |
| 188 | |
| 189 | full_path = build_unc_path_to_root(ctx, cifs_sb, true); |
| 190 | if (IS_ERR(full_path)) { |
| 191 | rc = PTR_ERR(full_path); |
| 192 | full_path = NULL; |
| 193 | goto out; |
| 194 | } |
| 195 | |
| 196 | origin_fullpath = kstrdup(full_path, GFP_KERNEL); |
| 197 | if (!origin_fullpath) { |
| 198 | rc = -ENOMEM; |
| 199 | goto out; |
| 200 | } |
| 201 | |
| 202 | do { |
| 203 | struct dfs_cache_tgt_list tl = DFS_CACHE_TGT_LIST_INIT(tl); |
| 204 | |
| 205 | rc = dfs_get_referral(mnt_ctx, ref_path + 1, NULL, &tl); |
| 206 | if (rc) |
| 207 | break; |
| 208 | |
| 209 | tit = dfs_cache_get_tgt_iterator(&tl); |
| 210 | if (!tit) { |
| 211 | cifs_dbg(VFS, "%s: dfs referral (%s) with no targets\n", __func__, |
| 212 | ref_path + 1); |
| 213 | rc = -ENOENT; |
| 214 | dfs_cache_free_tgts(&tl); |
| 215 | break; |
| 216 | } |
| 217 | |
| 218 | do { |
| 219 | rc = get_dfs_conn(mnt_ctx, ref_path, full_path, tit); |
| 220 | if (!rc) |
| 221 | break; |
| 222 | if (rc == -EREMOTE) { |
| 223 | if (++num_links > MAX_NESTED_LINKS) { |
| 224 | rc = -ELOOP; |
| 225 | break; |
| 226 | } |
| 227 | kfree(ref_path); |
| 228 | kfree(full_path); |
| 229 | ref_path = full_path = NULL; |
| 230 | |
| 231 | full_path = build_unc_path_to_root(ctx, cifs_sb, true); |
| 232 | if (IS_ERR(full_path)) { |
| 233 | rc = PTR_ERR(full_path); |
| 234 | full_path = NULL; |
| 235 | } else { |
| 236 | ref_path = dfs_get_path(cifs_sb, full_path); |
| 237 | if (IS_ERR(ref_path)) { |
| 238 | rc = PTR_ERR(ref_path); |
| 239 | ref_path = NULL; |
| 240 | } |
| 241 | } |
| 242 | break; |
| 243 | } |
| 244 | } while ((tit = dfs_cache_get_next_tgt(&tl, tit))); |
| 245 | dfs_cache_free_tgts(&tl); |
| 246 | } while (rc == -EREMOTE); |
| 247 | |
| 248 | if (!rc) { |
| 249 | server = mnt_ctx->server; |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 250 | tcon = mnt_ctx->tcon; |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 251 | |
| 252 | mutex_lock(&server->refpath_lock); |
Paulo Alcantara | 3dc9c43 | 2023-04-26 13:43:53 -0300 | [diff] [blame] | 253 | spin_lock(&server->srv_lock); |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 254 | if (!server->origin_fullpath) { |
| 255 | server->origin_fullpath = origin_fullpath; |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 256 | origin_fullpath = NULL; |
| 257 | } |
Paulo Alcantara | 3dc9c43 | 2023-04-26 13:43:53 -0300 | [diff] [blame] | 258 | spin_unlock(&server->srv_lock); |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 259 | mutex_unlock(&server->refpath_lock); |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 260 | |
| 261 | if (list_empty(&tcon->dfs_ses_list)) { |
| 262 | list_replace_init(&mnt_ctx->dfs_ses_list, |
| 263 | &tcon->dfs_ses_list); |
Paulo Alcantara | 6be2ea3 | 2023-04-27 04:40:08 -0300 | [diff] [blame] | 264 | queue_delayed_work(dfscache_wq, &tcon->dfs_cache_work, |
| 265 | dfs_cache_get_ttl() * HZ); |
Paulo Alcantara | 396935d | 2023-03-14 20:32:54 -0300 | [diff] [blame] | 266 | } else { |
| 267 | dfs_put_root_smb_sessions(&mnt_ctx->dfs_ses_list); |
| 268 | } |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 269 | } |
| 270 | |
| 271 | out: |
| 272 | kfree(origin_fullpath); |
| 273 | kfree(ref_path); |
| 274 | kfree(full_path); |
| 275 | return rc; |
| 276 | } |
| 277 | |
| 278 | int dfs_mount_share(struct cifs_mount_ctx *mnt_ctx, bool *isdfs) |
| 279 | { |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 280 | struct smb3_fs_context *ctx = mnt_ctx->fs_ctx; |
Paulo Alcantara | 8e35541 | 2023-04-23 23:26:51 -0300 | [diff] [blame] | 281 | struct cifs_ses *ses; |
| 282 | char *source = ctx->source; |
| 283 | bool nodfs = ctx->nodfs; |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 284 | int rc; |
| 285 | |
| 286 | *isdfs = false; |
Paulo Alcantara | 8e35541 | 2023-04-23 23:26:51 -0300 | [diff] [blame] | 287 | /* Temporarily set @ctx->source to NULL as we're not matching DFS |
| 288 | * superblocks yet. See cifs_match_super() and match_server(). |
| 289 | */ |
| 290 | ctx->source = NULL; |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 291 | rc = get_session(mnt_ctx, NULL); |
| 292 | if (rc) |
Paulo Alcantara | 8e35541 | 2023-04-23 23:26:51 -0300 | [diff] [blame] | 293 | goto out; |
| 294 | |
Paulo Alcantara | b56bce50 | 2023-03-14 20:32:53 -0300 | [diff] [blame] | 295 | ctx->dfs_root_ses = mnt_ctx->ses; |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 296 | /* |
| 297 | * If called with 'nodfs' mount option, then skip DFS resolving. Otherwise unconditionally |
| 298 | * try to get an DFS referral (even cached) to determine whether it is an DFS mount. |
| 299 | * |
| 300 | * Skip prefix path to provide support for DFS referrals from w2k8 servers which don't seem |
| 301 | * to respond with PATH_NOT_COVERED to requests that include the prefix. |
| 302 | */ |
Paulo Alcantara | 8e35541 | 2023-04-23 23:26:51 -0300 | [diff] [blame] | 303 | if (!nodfs) { |
| 304 | rc = dfs_get_referral(mnt_ctx, ctx->UNC + 1, NULL, NULL); |
| 305 | if (rc) { |
| 306 | if (rc != -ENOENT && rc != -EOPNOTSUPP) |
| 307 | goto out; |
| 308 | nodfs = true; |
| 309 | } |
| 310 | } |
| 311 | if (nodfs) { |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 312 | rc = cifs_mount_get_tcon(mnt_ctx); |
Paulo Alcantara | 8e35541 | 2023-04-23 23:26:51 -0300 | [diff] [blame] | 313 | if (!rc) |
| 314 | rc = cifs_is_path_remote(mnt_ctx); |
| 315 | goto out; |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 316 | } |
| 317 | |
| 318 | *isdfs = true; |
Paulo Alcantara | 8e35541 | 2023-04-23 23:26:51 -0300 | [diff] [blame] | 319 | /* |
| 320 | * Prevent DFS root session of being put in the first call to |
| 321 | * cifs_mount_put_conns(). If another DFS root server was not found |
| 322 | * while chasing the referrals (@ctx->dfs_root_ses == @ses), then we |
| 323 | * can safely put extra refcount of @ses. |
| 324 | */ |
| 325 | ses = mnt_ctx->ses; |
| 326 | mnt_ctx->ses = NULL; |
| 327 | mnt_ctx->server = NULL; |
| 328 | rc = __dfs_mount_share(mnt_ctx); |
| 329 | if (ses == ctx->dfs_root_ses) |
| 330 | cifs_put_smb_ses(ses); |
| 331 | out: |
| 332 | /* |
| 333 | * Restore previous value of @ctx->source so DFS superblock can be |
| 334 | * matched in cifs_match_super(). |
| 335 | */ |
| 336 | ctx->source = source; |
| 337 | return rc; |
Paulo Alcantara | a1c0d00 | 2022-11-17 13:23:49 -0300 | [diff] [blame] | 338 | } |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 339 | |
| 340 | /* Update dfs referral path of superblock */ |
| 341 | static int update_server_fullpath(struct TCP_Server_Info *server, struct cifs_sb_info *cifs_sb, |
| 342 | const char *target) |
| 343 | { |
| 344 | int rc = 0; |
| 345 | size_t len = strlen(target); |
| 346 | char *refpath, *npath; |
| 347 | |
| 348 | if (unlikely(len < 2 || *target != '\\')) |
| 349 | return -EINVAL; |
| 350 | |
| 351 | if (target[1] == '\\') { |
| 352 | len += 1; |
| 353 | refpath = kmalloc(len, GFP_KERNEL); |
| 354 | if (!refpath) |
| 355 | return -ENOMEM; |
| 356 | |
| 357 | scnprintf(refpath, len, "%s", target); |
| 358 | } else { |
| 359 | len += sizeof("\\"); |
| 360 | refpath = kmalloc(len, GFP_KERNEL); |
| 361 | if (!refpath) |
| 362 | return -ENOMEM; |
| 363 | |
| 364 | scnprintf(refpath, len, "\\%s", target); |
| 365 | } |
| 366 | |
| 367 | npath = dfs_cache_canonical_path(refpath, cifs_sb->local_nls, cifs_remap(cifs_sb)); |
| 368 | kfree(refpath); |
| 369 | |
| 370 | if (IS_ERR(npath)) { |
| 371 | rc = PTR_ERR(npath); |
| 372 | } else { |
| 373 | mutex_lock(&server->refpath_lock); |
Paulo Alcantara | 3dc9c43 | 2023-04-26 13:43:53 -0300 | [diff] [blame] | 374 | spin_lock(&server->srv_lock); |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 375 | kfree(server->leaf_fullpath); |
| 376 | server->leaf_fullpath = npath; |
Paulo Alcantara | 3dc9c43 | 2023-04-26 13:43:53 -0300 | [diff] [blame] | 377 | spin_unlock(&server->srv_lock); |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 378 | mutex_unlock(&server->refpath_lock); |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 379 | } |
| 380 | return rc; |
| 381 | } |
| 382 | |
Paulo Alcantara | 39a154fc | 2022-12-29 18:43:46 -0300 | [diff] [blame] | 383 | static int target_share_matches_server(struct TCP_Server_Info *server, char *share, |
| 384 | bool *target_match) |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 385 | { |
| 386 | int rc = 0; |
| 387 | const char *dfs_host; |
| 388 | size_t dfs_host_len; |
| 389 | |
| 390 | *target_match = true; |
| 391 | extract_unc_hostname(share, &dfs_host, &dfs_host_len); |
| 392 | |
| 393 | /* Check if hostnames or addresses match */ |
Paulo Alcantara | 39a154fc | 2022-12-29 18:43:46 -0300 | [diff] [blame] | 394 | cifs_server_lock(server); |
| 395 | if (dfs_host_len != strlen(server->hostname) || |
| 396 | strncasecmp(dfs_host, server->hostname, dfs_host_len)) { |
| 397 | cifs_dbg(FYI, "%s: %.*s doesn't match %s\n", __func__, |
| 398 | (int)dfs_host_len, dfs_host, server->hostname); |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 399 | rc = match_target_ip(server, dfs_host, dfs_host_len, target_match); |
| 400 | if (rc) |
| 401 | cifs_dbg(VFS, "%s: failed to match target ip: %d\n", __func__, rc); |
| 402 | } |
Paulo Alcantara | 39a154fc | 2022-12-29 18:43:46 -0300 | [diff] [blame] | 403 | cifs_server_unlock(server); |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 404 | return rc; |
| 405 | } |
| 406 | |
Paulo Alcantara | ee20d7c | 2023-04-25 02:42:56 -0300 | [diff] [blame] | 407 | static void __tree_connect_ipc(const unsigned int xid, char *tree, |
| 408 | struct cifs_sb_info *cifs_sb, |
| 409 | struct cifs_ses *ses) |
| 410 | { |
| 411 | struct TCP_Server_Info *server = ses->server; |
| 412 | struct cifs_tcon *tcon = ses->tcon_ipc; |
| 413 | int rc; |
| 414 | |
| 415 | spin_lock(&ses->ses_lock); |
| 416 | spin_lock(&ses->chan_lock); |
| 417 | if (cifs_chan_needs_reconnect(ses, server) || |
| 418 | ses->ses_status != SES_GOOD) { |
| 419 | spin_unlock(&ses->chan_lock); |
| 420 | spin_unlock(&ses->ses_lock); |
| 421 | cifs_server_dbg(FYI, "%s: skipping ipc reconnect due to disconnected ses\n", |
| 422 | __func__); |
| 423 | return; |
| 424 | } |
| 425 | spin_unlock(&ses->chan_lock); |
| 426 | spin_unlock(&ses->ses_lock); |
| 427 | |
| 428 | cifs_server_lock(server); |
| 429 | scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$", server->hostname); |
| 430 | cifs_server_unlock(server); |
| 431 | |
| 432 | rc = server->ops->tree_connect(xid, ses, tree, tcon, |
| 433 | cifs_sb->local_nls); |
| 434 | cifs_server_dbg(FYI, "%s: tree_reconnect %s: %d\n", __func__, tree, rc); |
| 435 | spin_lock(&tcon->tc_lock); |
| 436 | if (rc) { |
| 437 | tcon->status = TID_NEED_TCON; |
| 438 | } else { |
| 439 | tcon->status = TID_GOOD; |
| 440 | tcon->need_reconnect = false; |
| 441 | } |
| 442 | spin_unlock(&tcon->tc_lock); |
| 443 | } |
| 444 | |
| 445 | static void tree_connect_ipc(const unsigned int xid, char *tree, |
| 446 | struct cifs_sb_info *cifs_sb, |
| 447 | struct cifs_tcon *tcon) |
| 448 | { |
| 449 | struct cifs_ses *ses = tcon->ses; |
| 450 | |
| 451 | __tree_connect_ipc(xid, tree, cifs_sb, ses); |
| 452 | __tree_connect_ipc(xid, tree, cifs_sb, CIFS_DFS_ROOT_SES(ses)); |
| 453 | } |
| 454 | |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 455 | static int __tree_connect_dfs_target(const unsigned int xid, struct cifs_tcon *tcon, |
| 456 | struct cifs_sb_info *cifs_sb, char *tree, bool islink, |
| 457 | struct dfs_cache_tgt_list *tl) |
| 458 | { |
| 459 | int rc; |
| 460 | struct TCP_Server_Info *server = tcon->ses->server; |
| 461 | const struct smb_version_operations *ops = server->ops; |
| 462 | struct cifs_ses *root_ses = CIFS_DFS_ROOT_SES(tcon->ses); |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 463 | char *share = NULL, *prefix = NULL; |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 464 | struct dfs_cache_tgt_iterator *tit; |
| 465 | bool target_match; |
| 466 | |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 467 | tit = dfs_cache_get_tgt_iterator(tl); |
| 468 | if (!tit) { |
| 469 | rc = -ENOENT; |
| 470 | goto out; |
| 471 | } |
| 472 | |
| 473 | /* Try to tree connect to all dfs targets */ |
| 474 | for (; tit; tit = dfs_cache_get_next_tgt(tl, tit)) { |
| 475 | const char *target = dfs_cache_get_tgt_name(tit); |
| 476 | struct dfs_cache_tgt_list ntl = DFS_CACHE_TGT_LIST_INIT(ntl); |
| 477 | |
| 478 | kfree(share); |
| 479 | kfree(prefix); |
| 480 | share = prefix = NULL; |
| 481 | |
| 482 | /* Check if share matches with tcp ses */ |
Paulo Alcantara | 3dc9c43 | 2023-04-26 13:43:53 -0300 | [diff] [blame] | 483 | rc = dfs_cache_get_tgt_share(server->leaf_fullpath + 1, tit, &share, &prefix); |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 484 | if (rc) { |
| 485 | cifs_dbg(VFS, "%s: failed to parse target share: %d\n", __func__, rc); |
| 486 | break; |
| 487 | } |
| 488 | |
Paulo Alcantara | 39a154fc | 2022-12-29 18:43:46 -0300 | [diff] [blame] | 489 | rc = target_share_matches_server(server, share, &target_match); |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 490 | if (rc) |
| 491 | break; |
| 492 | if (!target_match) { |
| 493 | rc = -EHOSTUNREACH; |
| 494 | continue; |
| 495 | } |
| 496 | |
Paulo Alcantara | 3dc9c43 | 2023-04-26 13:43:53 -0300 | [diff] [blame] | 497 | dfs_cache_noreq_update_tgthint(server->leaf_fullpath + 1, tit); |
Paulo Alcantara | ee20d7c | 2023-04-25 02:42:56 -0300 | [diff] [blame] | 498 | tree_connect_ipc(xid, tree, cifs_sb, tcon); |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 499 | |
| 500 | scnprintf(tree, MAX_TREE_SIZE, "\\%s", share); |
| 501 | if (!islink) { |
| 502 | rc = ops->tree_connect(xid, tcon->ses, tree, tcon, cifs_sb->local_nls); |
| 503 | break; |
| 504 | } |
Paulo Alcantara | ee20d7c | 2023-04-25 02:42:56 -0300 | [diff] [blame] | 505 | |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 506 | /* |
| 507 | * If no dfs referrals were returned from link target, then just do a TREE_CONNECT |
| 508 | * to it. Otherwise, cache the dfs referral and then mark current tcp ses for |
| 509 | * reconnect so either the demultiplex thread or the echo worker will reconnect to |
| 510 | * newly resolved target. |
| 511 | */ |
| 512 | if (dfs_cache_find(xid, root_ses, cifs_sb->local_nls, cifs_remap(cifs_sb), target, |
| 513 | NULL, &ntl)) { |
| 514 | rc = ops->tree_connect(xid, tcon->ses, tree, tcon, cifs_sb->local_nls); |
| 515 | if (rc) |
| 516 | continue; |
| 517 | |
| 518 | rc = cifs_update_super_prepath(cifs_sb, prefix); |
| 519 | } else { |
| 520 | /* Target is another dfs share */ |
| 521 | rc = update_server_fullpath(server, cifs_sb, target); |
| 522 | dfs_cache_free_tgts(tl); |
| 523 | |
| 524 | if (!rc) { |
| 525 | rc = -EREMOTE; |
| 526 | list_replace_init(&ntl.tl_list, &tl->tl_list); |
| 527 | } else |
| 528 | dfs_cache_free_tgts(&ntl); |
| 529 | } |
| 530 | break; |
| 531 | } |
| 532 | |
| 533 | out: |
| 534 | kfree(share); |
| 535 | kfree(prefix); |
| 536 | |
| 537 | return rc; |
| 538 | } |
| 539 | |
| 540 | static int tree_connect_dfs_target(const unsigned int xid, struct cifs_tcon *tcon, |
| 541 | struct cifs_sb_info *cifs_sb, char *tree, bool islink, |
| 542 | struct dfs_cache_tgt_list *tl) |
| 543 | { |
| 544 | int rc; |
| 545 | int num_links = 0; |
| 546 | struct TCP_Server_Info *server = tcon->ses->server; |
Paulo Alcantara | 6fbdd5ab | 2022-12-17 00:46:11 -0300 | [diff] [blame] | 547 | char *old_fullpath = server->leaf_fullpath; |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 548 | |
| 549 | do { |
| 550 | rc = __tree_connect_dfs_target(xid, tcon, cifs_sb, tree, islink, tl); |
| 551 | if (!rc || rc != -EREMOTE) |
| 552 | break; |
| 553 | } while (rc = -ELOOP, ++num_links < MAX_NESTED_LINKS); |
| 554 | /* |
Paulo Alcantara | 6fbdd5ab | 2022-12-17 00:46:11 -0300 | [diff] [blame] | 555 | * If we couldn't tree connect to any targets from last referral path, then |
| 556 | * retry it from newly resolved dfs referral. |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 557 | */ |
Paulo Alcantara | 6fbdd5ab | 2022-12-17 00:46:11 -0300 | [diff] [blame] | 558 | if (rc && server->leaf_fullpath != old_fullpath) |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 559 | cifs_signal_cifsd_for_reconnect(server, true); |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 560 | |
| 561 | dfs_cache_free_tgts(tl); |
| 562 | return rc; |
| 563 | } |
| 564 | |
| 565 | int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc) |
| 566 | { |
| 567 | int rc; |
| 568 | struct TCP_Server_Info *server = tcon->ses->server; |
| 569 | const struct smb_version_operations *ops = server->ops; |
| 570 | struct super_block *sb = NULL; |
| 571 | struct cifs_sb_info *cifs_sb; |
| 572 | struct dfs_cache_tgt_list tl = DFS_CACHE_TGT_LIST_INIT(tl); |
| 573 | char *tree; |
| 574 | struct dfs_info3_param ref = {0}; |
| 575 | |
| 576 | /* only send once per connect */ |
| 577 | spin_lock(&tcon->tc_lock); |
Shyam Prasad N | 2f0e4f0 | 2023-03-16 10:45:12 +0000 | [diff] [blame] | 578 | if (tcon->status != TID_NEW && |
| 579 | tcon->status != TID_NEED_TCON) { |
| 580 | spin_unlock(&tcon->tc_lock); |
| 581 | return -EHOSTDOWN; |
| 582 | } |
| 583 | |
| 584 | if (tcon->status == TID_GOOD) { |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 585 | spin_unlock(&tcon->tc_lock); |
| 586 | return 0; |
| 587 | } |
| 588 | tcon->status = TID_IN_TCON; |
| 589 | spin_unlock(&tcon->tc_lock); |
| 590 | |
| 591 | tree = kzalloc(MAX_TREE_SIZE, GFP_KERNEL); |
| 592 | if (!tree) { |
| 593 | rc = -ENOMEM; |
| 594 | goto out; |
| 595 | } |
| 596 | |
| 597 | if (tcon->ipc) { |
Paulo Alcantara | 39a154fc | 2022-12-29 18:43:46 -0300 | [diff] [blame] | 598 | cifs_server_lock(server); |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 599 | scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$", server->hostname); |
Paulo Alcantara | 39a154fc | 2022-12-29 18:43:46 -0300 | [diff] [blame] | 600 | cifs_server_unlock(server); |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 601 | rc = ops->tree_connect(xid, tcon->ses, tree, tcon, nlsc); |
| 602 | goto out; |
| 603 | } |
| 604 | |
| 605 | sb = cifs_get_tcp_super(server); |
| 606 | if (IS_ERR(sb)) { |
| 607 | rc = PTR_ERR(sb); |
| 608 | cifs_dbg(VFS, "%s: could not find superblock: %d\n", __func__, rc); |
| 609 | goto out; |
| 610 | } |
| 611 | |
| 612 | cifs_sb = CIFS_SB(sb); |
| 613 | |
| 614 | /* If it is not dfs or there was no cached dfs referral, then reconnect to same share */ |
Paulo Alcantara | 3dc9c43 | 2023-04-26 13:43:53 -0300 | [diff] [blame] | 615 | if (!server->leaf_fullpath || |
| 616 | dfs_cache_noreq_find(server->leaf_fullpath + 1, &ref, &tl)) { |
Paulo Alcantara | 1d04a6f | 2022-12-16 21:41:31 -0300 | [diff] [blame] | 617 | rc = ops->tree_connect(xid, tcon->ses, tcon->tree_name, tcon, cifs_sb->local_nls); |
| 618 | goto out; |
| 619 | } |
| 620 | |
| 621 | rc = tree_connect_dfs_target(xid, tcon, cifs_sb, tree, ref.server_type == DFS_TYPE_LINK, |
| 622 | &tl); |
| 623 | free_dfs_info_param(&ref); |
| 624 | |
| 625 | out: |
| 626 | kfree(tree); |
| 627 | cifs_put_tcp_super(sb); |
| 628 | |
| 629 | if (rc) { |
| 630 | spin_lock(&tcon->tc_lock); |
| 631 | if (tcon->status == TID_IN_TCON) |
| 632 | tcon->status = TID_NEED_TCON; |
| 633 | spin_unlock(&tcon->tc_lock); |
| 634 | } else { |
| 635 | spin_lock(&tcon->tc_lock); |
| 636 | if (tcon->status == TID_IN_TCON) |
| 637 | tcon->status = TID_GOOD; |
| 638 | spin_unlock(&tcon->tc_lock); |
| 639 | tcon->need_reconnect = false; |
| 640 | } |
| 641 | |
| 642 | return rc; |
| 643 | } |