diff options
Diffstat (limited to 'fs/crypto/keyinfo.c')
-rw-r--r-- | fs/crypto/keyinfo.c | 99 |
1 files changed, 26 insertions, 73 deletions
diff --git a/fs/crypto/keyinfo.c b/fs/crypto/keyinfo.c index 95cd4c3b06c3..8cdfddce2b34 100644 --- a/fs/crypto/keyinfo.c +++ b/fs/crypto/keyinfo.c @@ -77,28 +77,25 @@ out: static int validate_user_key(struct fscrypt_info *crypt_info, struct fscrypt_context *ctx, u8 *raw_key, - u8 *prefix, int prefix_size) + const char *prefix) { - u8 *full_key_descriptor; + char *description; struct key *keyring_key; struct fscrypt_key *master_key; const struct user_key_payload *ukp; - int full_key_len = prefix_size + (FS_KEY_DESCRIPTOR_SIZE * 2) + 1; int res; - full_key_descriptor = kmalloc(full_key_len, GFP_NOFS); - if (!full_key_descriptor) + description = kasprintf(GFP_NOFS, "%s%*phN", prefix, + FS_KEY_DESCRIPTOR_SIZE, + ctx->master_key_descriptor); + if (!description) return -ENOMEM; - memcpy(full_key_descriptor, prefix, prefix_size); - sprintf(full_key_descriptor + prefix_size, - "%*phN", FS_KEY_DESCRIPTOR_SIZE, - ctx->master_key_descriptor); - full_key_descriptor[full_key_len - 1] = '\0'; - keyring_key = request_key(&key_type_logon, full_key_descriptor, NULL); - kfree(full_key_descriptor); + keyring_key = request_key(&key_type_logon, description, NULL); + kfree(description); if (IS_ERR(keyring_key)) return PTR_ERR(keyring_key); + down_read(&keyring_key->sem); if (keyring_key->type != &key_type_logon) { printk_once(KERN_WARNING @@ -106,11 +103,9 @@ static int validate_user_key(struct fscrypt_info *crypt_info, res = -ENOKEY; goto out; } - down_read(&keyring_key->sem); - ukp = user_key_payload(keyring_key); + ukp = user_key_payload_locked(keyring_key); if (ukp->datalen != sizeof(struct fscrypt_key)) { res = -EINVAL; - up_read(&keyring_key->sem); goto out; } master_key = (struct fscrypt_key *)ukp->data; @@ -121,17 +116,11 @@ static int validate_user_key(struct fscrypt_info *crypt_info, "%s: key size incorrect: %d\n", __func__, master_key->size); res = -ENOKEY; - up_read(&keyring_key->sem); goto out; } res = derive_key_aes(ctx->nonce, master_key->raw, raw_key); - up_read(&keyring_key->sem); - if (res) - goto out; - - crypt_info->ci_keyring_key = keyring_key; - return 0; out: + up_read(&keyring_key->sem); key_put(keyring_key); return res; } @@ -173,12 +162,11 @@ static void put_crypt_info(struct fscrypt_info *ci) if (!ci) return; - key_put(ci->ci_keyring_key); crypto_free_skcipher(ci->ci_ctfm); kmem_cache_free(fscrypt_info_cachep, ci); } -int fscrypt_get_crypt_info(struct inode *inode) +int fscrypt_get_encryption_info(struct inode *inode) { struct fscrypt_info *crypt_info; struct fscrypt_context ctx; @@ -188,30 +176,27 @@ int fscrypt_get_crypt_info(struct inode *inode) u8 *raw_key = NULL; int res; + if (inode->i_crypt_info) + return 0; + res = fscrypt_initialize(inode->i_sb->s_cop->flags); if (res) return res; if (!inode->i_sb->s_cop->get_context) return -EOPNOTSUPP; -retry: - crypt_info = ACCESS_ONCE(inode->i_crypt_info); - if (crypt_info) { - if (!crypt_info->ci_keyring_key || - key_validate(crypt_info->ci_keyring_key) == 0) - return 0; - fscrypt_put_encryption_info(inode, crypt_info); - goto retry; - } res = inode->i_sb->s_cop->get_context(inode, &ctx, sizeof(ctx)); if (res < 0) { - if (!fscrypt_dummy_context_enabled(inode)) + if (!fscrypt_dummy_context_enabled(inode) || + inode->i_sb->s_cop->is_encrypted(inode)) return res; + /* Fake up a context for an unencrypted directory */ + memset(&ctx, 0, sizeof(ctx)); ctx.format = FS_ENCRYPTION_CONTEXT_FORMAT_V1; ctx.contents_encryption_mode = FS_ENCRYPTION_MODE_AES_256_XTS; ctx.filenames_encryption_mode = FS_ENCRYPTION_MODE_AES_256_CTS; - ctx.flags = 0; + memset(ctx.master_key_descriptor, 0x42, FS_KEY_DESCRIPTOR_SIZE); } else if (res != sizeof(ctx)) { return -EINVAL; } @@ -230,7 +215,6 @@ retry: crypt_info->ci_data_mode = ctx.contents_encryption_mode; crypt_info->ci_filename_mode = ctx.filenames_encryption_mode; crypt_info->ci_ctfm = NULL; - crypt_info->ci_keyring_key = NULL; memcpy(crypt_info->ci_master_key, ctx.master_key_descriptor, sizeof(crypt_info->ci_master_key)); @@ -247,21 +231,10 @@ retry: if (!raw_key) goto out; - if (fscrypt_dummy_context_enabled(inode)) { - memset(raw_key, 0x42, keysize/2); - memset(raw_key+keysize/2, 0x24, keysize - (keysize/2)); - goto got_key; - } - - res = validate_user_key(crypt_info, &ctx, raw_key, - FS_KEY_DESC_PREFIX, FS_KEY_DESC_PREFIX_SIZE); + res = validate_user_key(crypt_info, &ctx, raw_key, FS_KEY_DESC_PREFIX); if (res && inode->i_sb->s_cop->key_prefix) { - u8 *prefix = NULL; - int prefix_size, res2; - - prefix_size = inode->i_sb->s_cop->key_prefix(inode, &prefix); - res2 = validate_user_key(crypt_info, &ctx, raw_key, - prefix, prefix_size); + int res2 = validate_user_key(crypt_info, &ctx, raw_key, + inode->i_sb->s_cop->key_prefix); if (res2) { if (res2 == -ENOKEY) res = -ENOKEY; @@ -270,7 +243,6 @@ retry: } else if (res) { goto out; } -got_key: ctfm = crypto_alloc_skcipher(cipher_str, 0, 0); if (!ctfm || IS_ERR(ctfm)) { res = ctfm ? PTR_ERR(ctfm) : -ENOMEM; @@ -286,14 +258,8 @@ got_key: if (res) goto out; - kzfree(raw_key); - raw_key = NULL; - if (cmpxchg(&inode->i_crypt_info, NULL, crypt_info) != NULL) { - put_crypt_info(crypt_info); - goto retry; - } - return 0; - + if (cmpxchg(&inode->i_crypt_info, NULL, crypt_info) == NULL) + crypt_info = NULL; out: if (res == -ENOKEY) res = 0; @@ -301,6 +267,7 @@ out: kzfree(raw_key); return res; } +EXPORT_SYMBOL(fscrypt_get_encryption_info); void fscrypt_put_encryption_info(struct inode *inode, struct fscrypt_info *ci) { @@ -318,17 +285,3 @@ void fscrypt_put_encryption_info(struct inode *inode, struct fscrypt_info *ci) put_crypt_info(ci); } EXPORT_SYMBOL(fscrypt_put_encryption_info); - -int fscrypt_get_encryption_info(struct inode *inode) -{ - struct fscrypt_info *ci = inode->i_crypt_info; - - if (!ci || - (ci->ci_keyring_key && - (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) | - (1 << KEY_FLAG_REVOKED) | - (1 << KEY_FLAG_DEAD))))) - return fscrypt_get_crypt_info(inode); - return 0; -} -EXPORT_SYMBOL(fscrypt_get_encryption_info); |