diff options
Diffstat (limited to 'fs/ext4/crypto_fname.c')
-rw-r--r-- | fs/ext4/crypto_fname.c | 155 |
1 files changed, 64 insertions, 91 deletions
diff --git a/fs/ext4/crypto_fname.c b/fs/ext4/crypto_fname.c index fded02f72299..ad5e32867de0 100644 --- a/fs/ext4/crypto_fname.c +++ b/fs/ext4/crypto_fname.c @@ -611,109 +611,82 @@ int ext4_fname_usr_to_disk(struct ext4_fname_crypto_ctx *ctx, return -EACCES; } -/* - * Calculate the htree hash from a filename from user space - */ -int ext4_fname_usr_to_hash(struct ext4_fname_crypto_ctx *ctx, - const struct qstr *iname, - struct dx_hash_info *hinfo) +int ext4_fname_setup_filename(struct inode *dir, const struct qstr *iname, + int lookup, struct ext4_filename *fname) { - struct ext4_str tmp; - int ret = 0; - char buf[EXT4_FNAME_CRYPTO_DIGEST_SIZE+1]; + struct ext4_fname_crypto_ctx *ctx; + int ret = 0, bigname = 0; + + memset(fname, 0, sizeof(struct ext4_filename)); + fname->usr_fname = iname; - if (!ctx || + ctx = ext4_get_fname_crypto_ctx(dir, EXT4_NAME_LEN); + if (IS_ERR(ctx)) + return PTR_ERR(ctx); + if ((ctx == NULL) || ((iname->name[0] == '.') && ((iname->len == 1) || ((iname->name[1] == '.') && (iname->len == 2))))) { - ext4fs_dirhash(iname->name, iname->len, hinfo); - return 0; + fname->disk_name.name = (unsigned char *) iname->name; + fname->disk_name.len = iname->len; + goto out; } - - if (!ctx->has_valid_key && iname->name[0] == '_') { - if (iname->len != 33) - return -ENOENT; - ret = digest_decode(iname->name+1, iname->len, buf); - if (ret != 24) - return -ENOENT; - memcpy(&hinfo->hash, buf, 4); - memcpy(&hinfo->minor_hash, buf + 4, 4); - return 0; + if (ctx->has_valid_key) { + ret = ext4_fname_crypto_alloc_buffer(ctx, iname->len, + &fname->crypto_buf); + if (ret < 0) + goto out; + ret = ext4_fname_encrypt(ctx, iname, &fname->crypto_buf); + if (ret < 0) + goto out; + fname->disk_name.name = fname->crypto_buf.name; + fname->disk_name.len = fname->crypto_buf.len; + ret = 0; + goto out; } - - if (!ctx->has_valid_key && iname->name[0] != '_') { - if (iname->len > 43) - return -ENOENT; - ret = digest_decode(iname->name, iname->len, buf); - ext4fs_dirhash(buf, ret, hinfo); - return 0; + if (!lookup) { + ret = -EACCES; + goto out; } - /* First encrypt the plaintext name */ - ret = ext4_fname_crypto_alloc_buffer(ctx, iname->len, &tmp); - if (ret < 0) - return ret; - - ret = ext4_fname_encrypt(ctx, iname, &tmp); - if (ret >= 0) { - ext4fs_dirhash(tmp.name, tmp.len, hinfo); - ret = 0; + /* We don't have the key and we are doing a lookup; decode the + * user-supplied name + */ + if (iname->name[0] == '_') + bigname = 1; + if ((bigname && (iname->len != 33)) || + (!bigname && (iname->len > 43))) { + ret = -ENOENT; } - - ext4_fname_crypto_free_buffer(&tmp); + fname->crypto_buf.name = kmalloc(32, GFP_KERNEL); + if (fname->crypto_buf.name == NULL) { + ret = -ENOMEM; + goto out; + } + ret = digest_decode(iname->name + bigname, iname->len - bigname, + fname->crypto_buf.name); + if (ret < 0) { + ret = -ENOENT; + goto out; + } + fname->crypto_buf.len = ret; + if (bigname) { + memcpy(&fname->hinfo.hash, fname->crypto_buf.name, 4); + memcpy(&fname->hinfo.minor_hash, fname->crypto_buf.name + 4, 4); + } else { + fname->disk_name.name = fname->crypto_buf.name; + fname->disk_name.len = fname->crypto_buf.len; + } + ret = 0; +out: + ext4_put_fname_crypto_ctx(&ctx); return ret; } -int ext4_fname_match(struct ext4_fname_crypto_ctx *ctx, struct ext4_str *cstr, - int len, const char * const name, - struct ext4_dir_entry_2 *de) +void ext4_fname_free_filename(struct ext4_filename *fname) { - int ret = -ENOENT; - int bigname = (*name == '_'); - - if (ctx->has_valid_key) { - if (cstr->name == NULL) { - struct qstr istr; - - ret = ext4_fname_crypto_alloc_buffer(ctx, len, cstr); - if (ret < 0) - goto errout; - istr.name = name; - istr.len = len; - ret = ext4_fname_encrypt(ctx, &istr, cstr); - if (ret < 0) - goto errout; - } - } else { - if (cstr->name == NULL) { - cstr->name = kmalloc(32, GFP_KERNEL); - if (cstr->name == NULL) - return -ENOMEM; - if ((bigname && (len != 33)) || - (!bigname && (len > 43))) - goto errout; - ret = digest_decode(name+bigname, len-bigname, - cstr->name); - if (ret < 0) { - ret = -ENOENT; - goto errout; - } - cstr->len = ret; - } - if (bigname) { - if (de->name_len < 16) - return 0; - ret = memcmp(de->name + de->name_len - 16, - cstr->name + 8, 16); - return (ret == 0) ? 1 : 0; - } - } - if (de->name_len != cstr->len) - return 0; - ret = memcmp(de->name, cstr->name, cstr->len); - return (ret == 0) ? 1 : 0; -errout: - kfree(cstr->name); - cstr->name = NULL; - return ret; + kfree(fname->crypto_buf.name); + fname->crypto_buf.name = NULL; + fname->usr_fname = NULL; + fname->disk_name.name = NULL; } |