| 1 | #ifndef MYSQL_SERVICE_ENCRYPTION_SCHEME_INCLUDED |
| 2 | /* Copyright (c) 2015, MariaDB |
| 3 | |
| 4 | This program is free software; you can redistribute it and/or modify |
| 5 | it under the terms of the GNU General Public License as published by |
| 6 | the Free Software Foundation; version 2 of the License. |
| 7 | |
| 8 | This program is distributed in the hope that it will be useful, |
| 9 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 11 | GNU General Public License for more details. |
| 12 | |
| 13 | You should have received a copy of the GNU General Public License |
| 14 | along with this program; if not, write to the Free Software |
| 15 | Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ |
| 16 | |
| 17 | /** |
| 18 | @file |
| 19 | encryption scheme service |
| 20 | |
| 21 | A higher-level access to encryption service. |
| 22 | |
| 23 | This is a helper service that storage engines use to encrypt tables on disk. |
| 24 | It requests keys from the plugin, generates temporary or local keys |
| 25 | from the global (as returned by the plugin) keys, etc. |
| 26 | |
| 27 | To use the service: |
| 28 | |
| 29 | * st_encryption_scheme object is created per space. A "space" can be |
| 30 | a table space in XtraDB/InnoDB, a file in Aria, etc. The whole |
| 31 | space is encrypted with the one key id. |
| 32 | |
| 33 | * The service does not take the key and the IV as parameters for |
| 34 | encryption or decryption. Instead it takes two 32-bit integers and |
| 35 | one 64-bit integer (and requests the key from an encryption |
| 36 | plugin, if needed). |
| 37 | |
| 38 | * The service requests the global key from the encryption plugin |
| 39 | automatically as needed. Three last keys are cached in the |
| 40 | st_encryption_scheme. Number of key requests (number of cache |
| 41 | misses) are counted in st_encryption_scheme::keyserver_requests |
| 42 | |
| 43 | * If an st_encryption_scheme can be used concurrently by different |
| 44 | threads, it needs to be able to lock itself when accessing the key |
| 45 | cache. Set the st_encryption_scheme::locker appropriately. If |
| 46 | non-zero, it will be invoked by encrypt/decrypt functions to lock |
| 47 | and unlock the scheme when needed. |
| 48 | |
| 49 | * Implementation details (in particular, key derivation) are defined |
| 50 | by the scheme type. Currently only schema type 1 is supported. |
| 51 | |
| 52 | In the schema type 1, every "space" (table space in XtraDB/InnoDB, |
| 53 | file in Aria) is encrypted with a different space-local key: |
| 54 | |
| 55 | * Every space has a 16-byte unique identifier (typically it's |
| 56 | generated randomly and stored in the space). The caller should |
| 57 | put it into st_encryption_scheme::iv. |
| 58 | |
| 59 | * Space-local key is generated by encrypting this identifier with |
| 60 | the global encryption key (of the given id and version) using AES_ECB. |
| 61 | |
| 62 | * Encryption/decryption parameters for a page are typically the |
| 63 | 4-byte space id, 4-byte page position (offset, page number, etc), |
| 64 | and the 8-byte LSN. This guarantees that they'll be different for |
| 65 | any two pages (of the same or different tablespaces) and also that |
| 66 | they'll change for the same page when it's modified. They don't need |
| 67 | to be secret (they create the IV, not the encryption key). |
| 68 | */ |
| 69 | |
| 70 | #ifdef __cplusplus |
| 71 | extern "C" { |
| 72 | #endif |
| 73 | |
| 74 | #define ENCRYPTION_SCHEME_KEY_INVALID -1 |
| 75 | #define ENCRYPTION_SCHEME_BLOCK_LENGTH 16 |
| 76 | |
| 77 | struct st_encryption_scheme_key { |
| 78 | unsigned int version; |
| 79 | unsigned char key[ENCRYPTION_SCHEME_BLOCK_LENGTH]; |
| 80 | }; |
| 81 | |
| 82 | struct st_encryption_scheme { |
| 83 | unsigned char iv[ENCRYPTION_SCHEME_BLOCK_LENGTH]; |
| 84 | struct st_encryption_scheme_key key[3]; |
| 85 | unsigned int keyserver_requests; |
| 86 | unsigned int key_id; |
| 87 | unsigned int type; |
| 88 | |
| 89 | void (*locker)(struct st_encryption_scheme *self, int release); |
| 90 | }; |
| 91 | |
| 92 | extern struct encryption_scheme_service_st { |
| 93 | int (*encryption_scheme_encrypt_func) |
| 94 | (const unsigned char* src, unsigned int slen, |
| 95 | unsigned char* dst, unsigned int* dlen, |
| 96 | struct st_encryption_scheme *scheme, |
| 97 | unsigned int key_version, unsigned int i32_1, |
| 98 | unsigned int i32_2, unsigned long long i64); |
| 99 | int (*encryption_scheme_decrypt_func) |
| 100 | (const unsigned char* src, unsigned int slen, |
| 101 | unsigned char* dst, unsigned int* dlen, |
| 102 | struct st_encryption_scheme *scheme, |
| 103 | unsigned int key_version, unsigned int i32_1, |
| 104 | unsigned int i32_2, unsigned long long i64); |
| 105 | } *encryption_scheme_service; |
| 106 | |
| 107 | #ifdef MYSQL_DYNAMIC_PLUGIN |
| 108 | |
| 109 | #define encryption_scheme_encrypt(S,SL,D,DL,SCH,KV,I32,J32,I64) encryption_scheme_service->encryption_scheme_encrypt_func(S,SL,D,DL,SCH,KV,I32,J32,I64) |
| 110 | #define encryption_scheme_decrypt(S,SL,D,DL,SCH,KV,I32,J32,I64) encryption_scheme_service->encryption_scheme_decrypt_func(S,SL,D,DL,SCH,KV,I32,J32,I64) |
| 111 | |
| 112 | #else |
| 113 | |
| 114 | int encryption_scheme_encrypt(const unsigned char* src, unsigned int slen, |
| 115 | unsigned char* dst, unsigned int* dlen, |
| 116 | struct st_encryption_scheme *scheme, |
| 117 | unsigned int key_version, unsigned int i32_1, |
| 118 | unsigned int i32_2, unsigned long long i64); |
| 119 | int encryption_scheme_decrypt(const unsigned char* src, unsigned int slen, |
| 120 | unsigned char* dst, unsigned int* dlen, |
| 121 | struct st_encryption_scheme *scheme, |
| 122 | unsigned int key_version, unsigned int i32_1, |
| 123 | unsigned int i32_2, unsigned long long i64); |
| 124 | |
| 125 | #endif |
| 126 | |
| 127 | |
| 128 | #ifdef __cplusplus |
| 129 | } |
| 130 | #endif |
| 131 | |
| 132 | #define MYSQL_SERVICE_ENCRYPTION_SCHEME_INCLUDED |
| 133 | #endif |
| 134 | |