/* * encrypted_init - initialize an encrypted key * * For a new key, use a random number for both the iv and data * itself. For an old key, decrypt the hex encoded data. */ static int encrypted_init(struct encrypted_key_payload *epayload, const char *key_desc, const char *format, const char *master_desc, const char *datalen, const char *hex_encoded_iv) { int ret = 0; if (format && !strcmp(format, key_format_ecryptfs)) { ret = valid_ecryptfs_desc(key_desc); if (ret < 0) return ret; ecryptfs_fill_auth_tok((struct ecryptfs_auth_tok *)epayload->payload_data, key_desc); } __ekey_init(epayload, format, master_desc, datalen); if (!hex_encoded_iv) { get_random_bytes(epayload->iv, ivsize); get_random_bytes(epayload->decrypted_data, epayload->decrypted_datalen); } else ret = encrypted_key_decrypt(epayload, format, hex_encoded_iv); return ret; }
/* * encrypted_update - update the master key description * * Change the master key description for an existing encrypted key. * The next read will return an encrypted datablob using the new * master key description. * * On success, return 0. Otherwise return errno. */ static int encrypted_update(struct key *key, struct key_preparsed_payload *prep) { struct encrypted_key_payload *epayload = key->payload.data[0]; struct encrypted_key_payload *new_epayload; char *buf; char *new_master_desc = NULL; const char *format = NULL; size_t datalen = prep->datalen; int ret = 0; if (test_bit(KEY_FLAG_NEGATIVE, &key->flags)) return -ENOKEY; if (datalen <= 0 || datalen > 32767 || !prep->data) return -EINVAL; buf = kmalloc(datalen + 1, GFP_KERNEL); if (!buf) return -ENOMEM; buf[datalen] = 0; memcpy(buf, prep->data, datalen); ret = datablob_parse(buf, &format, &new_master_desc, NULL, NULL); if (ret < 0) goto out; ret = valid_master_desc(new_master_desc, epayload->master_desc); if (ret < 0) goto out; new_epayload = encrypted_key_alloc(key, epayload->format, new_master_desc, epayload->datalen); if (IS_ERR(new_epayload)) { ret = PTR_ERR(new_epayload); goto out; } __ekey_init(new_epayload, epayload->format, new_master_desc, epayload->datalen); memcpy(new_epayload->iv, epayload->iv, ivsize); memcpy(new_epayload->payload_data, epayload->payload_data, epayload->payload_datalen); rcu_assign_keypointer(key, new_epayload); call_rcu(&epayload->rcu, encrypted_rcu_free); out: kfree(buf); return ret; }