diff options
| -rw-r--r-- | fs/ecryptfs/keystore.c | 78 |
1 files changed, 33 insertions, 45 deletions
diff --git a/fs/ecryptfs/keystore.c b/fs/ecryptfs/keystore.c index 8eb0746313d..f7debe6961d 100644 --- a/fs/ecryptfs/keystore.c +++ b/fs/ecryptfs/keystore.c @@ -512,72 +512,64 @@ parse_tag_1_packet(struct ecryptfs_crypt_stat *crypt_stat, (*packet_size) = 0; (*new_auth_tok) = NULL; - - /* we check that: - * one byte for the Tag 1 ID flag - * two bytes for the body size - * do not exceed the maximum_packet_size + /** + * This format is inspired by OpenPGP; see RFC 2440 + * packet tag 1 + * + * Tag 1 identifier (1 byte) + * Max Tag 1 packet size (max 3 bytes) + * Version (1 byte) + * Key identifier (8 bytes; ECRYPTFS_SIG_SIZE) + * Cipher identifier (1 byte) + * Encrypted key size (arbitrary) + * + * 12 bytes minimum packet size */ - if (unlikely((*packet_size) + 3 > max_packet_size)) { - ecryptfs_printk(KERN_ERR, "Packet size exceeds max\n"); + if (unlikely(max_packet_size < 12)) { + printk(KERN_ERR "Invalid max packet size; must be >=12\n"); rc = -EINVAL; goto out; } - /* check for Tag 1 identifier - one byte */ if (data[(*packet_size)++] != ECRYPTFS_TAG_1_PACKET_TYPE) { - ecryptfs_printk(KERN_ERR, "Enter w/ first byte != 0x%.2x\n", - ECRYPTFS_TAG_1_PACKET_TYPE); + printk(KERN_ERR "Enter w/ first byte != 0x%.2x\n", + ECRYPTFS_TAG_1_PACKET_TYPE); rc = -EINVAL; goto out; } /* Released: wipe_auth_tok_list called in ecryptfs_parse_packet_set or * at end of function upon failure */ auth_tok_list_item = - kmem_cache_alloc(ecryptfs_auth_tok_list_item_cache, - GFP_KERNEL); + kmem_cache_zalloc(ecryptfs_auth_tok_list_item_cache, + GFP_KERNEL); if (!auth_tok_list_item) { - ecryptfs_printk(KERN_ERR, "Unable to allocate memory\n"); + printk(KERN_ERR "Unable to allocate memory\n"); rc = -ENOMEM; goto out; } - memset(auth_tok_list_item, 0, - sizeof(struct ecryptfs_auth_tok_list_item)); (*new_auth_tok) = &auth_tok_list_item->auth_tok; - /* check for body size - one to two bytes - * - * ***** TAG 1 Packet Format ***** - * | version number | 1 byte | - * | key ID | 8 bytes | - * | public key algorithm | 1 byte | - * | encrypted session key | arbitrary | - */ - rc = parse_packet_length(&data[(*packet_size)], &body_size, - &length_size); - if (rc) { - ecryptfs_printk(KERN_WARNING, "Error parsing packet length; " - "rc = [%d]\n", rc); + if ((rc = parse_packet_length(&data[(*packet_size)], &body_size, + &length_size))) { + printk(KERN_WARNING "Error parsing packet length; " + "rc = [%d]\n", rc); goto out_free; } - if (unlikely(body_size < (0x02 + ECRYPTFS_SIG_SIZE))) { - ecryptfs_printk(KERN_WARNING, "Invalid body size ([%d])\n", - body_size); + if (unlikely(body_size < (ECRYPTFS_SIG_SIZE + 2))) { + printk(KERN_WARNING "Invalid body size ([%d])\n", body_size); rc = -EINVAL; goto out_free; } (*packet_size) += length_size; if (unlikely((*packet_size) + body_size > max_packet_size)) { - ecryptfs_printk(KERN_ERR, "Packet size exceeds max\n"); + printk(KERN_WARNING "Packet size exceeds max\n"); rc = -EINVAL; goto out_free; } - /* Version 3 (from RFC2440) - one byte */ if (unlikely(data[(*packet_size)++] != 0x03)) { - ecryptfs_printk(KERN_DEBUG, "Unknown version number " - "[%d]\n", data[(*packet_size) - 1]); + printk(KERN_WARNING "Unknown version number [%d]\n", + data[(*packet_size) - 1]); rc = -EINVAL; goto out_free; } - /* Read Signature */ ecryptfs_to_hex((*new_auth_tok)->token.private_key.signature, &data[(*packet_size)], ECRYPTFS_SIG_SIZE); *packet_size += ECRYPTFS_SIG_SIZE; @@ -585,27 +577,23 @@ parse_tag_1_packet(struct ecryptfs_crypt_stat *crypt_stat, * know which public key encryption algorithm was used */ (*packet_size)++; (*new_auth_tok)->session_key.encrypted_key_size = - body_size - (0x02 + ECRYPTFS_SIG_SIZE); + body_size - (ECRYPTFS_SIG_SIZE + 2); if ((*new_auth_tok)->session_key.encrypted_key_size > ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES) { - ecryptfs_printk(KERN_ERR, "Tag 1 packet contains key larger " - "than ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES"); + printk(KERN_WARNING "Tag 1 packet contains key larger " + "than ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES"); rc = -EINVAL; goto out; } - ecryptfs_printk(KERN_DEBUG, "Encrypted key size = [%d]\n", - (*new_auth_tok)->session_key.encrypted_key_size); memcpy((*new_auth_tok)->session_key.encrypted_key, - &data[(*packet_size)], (body_size - 0x02 - ECRYPTFS_SIG_SIZE)); + &data[(*packet_size)], (body_size - (ECRYPTFS_SIG_SIZE + 2))); (*packet_size) += (*new_auth_tok)->session_key.encrypted_key_size; (*new_auth_tok)->session_key.flags &= ~ECRYPTFS_CONTAINS_DECRYPTED_KEY; (*new_auth_tok)->session_key.flags |= ECRYPTFS_CONTAINS_ENCRYPTED_KEY; (*new_auth_tok)->token_type = ECRYPTFS_PRIVATE_KEY; - (*new_auth_tok)->flags |= ECRYPTFS_PRIVATE_KEY; - /* TODO: Why are we setting this flag here? Don't we want the - * userspace to decrypt the session key? */ + (*new_auth_tok)->flags = 0; (*new_auth_tok)->session_key.flags &= ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT); (*new_auth_tok)->session_key.flags &= |