| Vadim Bendebury | 5679752 | 2015-05-20 10:32:25 -0700 | [diff] [blame] | 1 | // This file was extracted from the TCG Published |
| 2 | // Trusted Platform Module Library |
| 3 | // Part 4: Supporting Routines |
| 4 | // Family "2.0" |
| 5 | // Level 00 Revision 01.16 |
| 6 | // October 30, 2014 |
| 7 | |
| 8 | //#define __TPM_RNG_FOR_DEBUG__ |
| 9 | // |
| 10 | // |
| 11 | // Introduction |
| 12 | // |
| 13 | // This file contains the interface to the OpenSSL() random number functions. |
| 14 | // |
| 15 | // Includes |
| 16 | // |
| 17 | #include "OsslCryptoEngine.h" |
| 18 | int s_entropyFailure; |
| 19 | // |
| 20 | // |
| 21 | // Functions |
| 22 | // |
| 23 | // _cpri__RngStartup() |
| 24 | // |
| 25 | // This function is called to initialize the random number generator. It collects entropy from the platform to |
| 26 | // seed the OpenSSL() random number generator. |
| 27 | // |
| 28 | LIB_EXPORT BOOL |
| 29 | _cpri__RngStartup(void) |
| 30 | { |
| 31 | UINT32 entropySize; |
| 32 | BYTE entropy[MAX_RNG_ENTROPY_SIZE]; |
| 33 | INT32 returnedSize = 0; |
| 34 | // Initialize the entropy source |
| 35 | s_entropyFailure = FALSE; |
| 36 | _plat__GetEntropy(NULL, 0); |
| 37 | // Collect entropy until we have enough |
| 38 | for(entropySize = 0; |
| 39 | entropySize < MAX_RNG_ENTROPY_SIZE && returnedSize >= 0; |
| 40 | entropySize += returnedSize) |
| 41 | { |
| 42 | returnedSize = _plat__GetEntropy(&entropy[entropySize], |
| 43 | MAX_RNG_ENTROPY_SIZE - entropySize); |
| 44 | } |
| 45 | // Got some entropy on the last call and did not get an error |
| 46 | if(returnedSize > 0) |
| 47 | { |
| 48 | // Seed OpenSSL with entropy |
| 49 | RAND_seed(entropy, entropySize); |
| 50 | } |
| 51 | else |
| 52 | { |
| 53 | s_entropyFailure = TRUE; |
| 54 | } |
| 55 | return s_entropyFailure == FALSE; |
| 56 | } |
| 57 | // |
| 58 | // |
| 59 | // _cpri__DrbgGetPutState() |
| 60 | // |
| 61 | // This function is used to set the state of the RNG (direction == PUT_STATE) or to recover the state of the |
| 62 | // RNG (direction == GET_STATE). |
| 63 | // |
| 64 | // |
| 65 | // |
| 66 | // NOTE: This not currently supported on OpenSSL() version. |
| 67 | // |
| 68 | LIB_EXPORT CRYPT_RESULT |
| 69 | _cpri__DrbgGetPutState( |
| 70 | GET_PUT direction, |
| 71 | int bufferSize, |
| 72 | BYTE *buffer |
| 73 | ) |
| 74 | { |
| 75 | UNREFERENCED_PARAMETER(direction); |
| 76 | UNREFERENCED_PARAMETER(bufferSize); |
| 77 | UNREFERENCED_PARAMETER(buffer); |
| 78 | return CRYPT_SUCCESS; // Function is not implemented |
| 79 | } |
| 80 | // |
| 81 | // |
| 82 | // _cpri__StirRandom() |
| 83 | // |
| 84 | // This function is called to add external entropy to the OpenSSL() random number generator. |
| 85 | // |
| 86 | LIB_EXPORT CRYPT_RESULT |
| 87 | _cpri__StirRandom( |
| 88 | INT32 entropySize, |
| 89 | BYTE *entropy |
| 90 | ) |
| 91 | { |
| 92 | if (entropySize >= 0) |
| 93 | { |
| 94 | RAND_add((const void *)entropy, (int) entropySize, 0.0); |
| 95 | } |
| 96 | return CRYPT_SUCCESS; |
| 97 | } |
| 98 | // |
| 99 | // |
| 100 | // _cpri__GenerateRandom() |
| 101 | // |
| 102 | // This function is called to get a string of random bytes from the OpenSSL() random number generator. The |
| 103 | // return value is the number of bytes placed in the buffer. If the number of bytes returned is not equal to the |
| 104 | // number of bytes requested (randomSize) it is indicative of a failure of the OpenSSL() random number |
| 105 | // generator and is probably fatal. |
| 106 | // |
| 107 | LIB_EXPORT UINT16 |
| 108 | _cpri__GenerateRandom( |
| 109 | INT32 randomSize, |
| 110 | BYTE *buffer |
| 111 | ) |
| 112 | { |
| 113 | // |
| 114 | // We don't do negative sizes or ones that are too large |
| 115 | if (randomSize < 0 || randomSize > UINT16_MAX) |
| 116 | return 0; |
| 117 | // RAND_bytes uses 1 for success and we use 0 |
| 118 | if(RAND_bytes(buffer, randomSize) == 1) |
| 119 | return (UINT16)randomSize; |
| 120 | else |
| 121 | return 0; |
| 122 | } |
| 123 | // |
| 124 | // |
| 125 | // |
| 126 | // _cpri__GenerateSeededRandom() |
| 127 | // |
| 128 | // This funciton is used to generate a pseudo-random number from some seed values This funciton returns |
| 129 | // the same result each time it is called with the same parameters |
| 130 | // |
| 131 | LIB_EXPORT UINT16 |
| 132 | _cpri__GenerateSeededRandom( |
| 133 | INT32 randomSize, // IN: the size of the request |
| 134 | BYTE *random, // OUT: receives the data |
| 135 | TPM_ALG_ID hashAlg, // IN: used by KDF version but not here |
| 136 | TPM2B *seed, // IN: the seed value |
| 137 | const char *label, // IN: a label string (optional) |
| 138 | TPM2B *partyU, // IN: other data (oprtional) |
| 139 | TPM2B *partyV // IN: still more (optional) |
| 140 | ) |
| 141 | { |
| 142 | return (_cpri__KDFa(hashAlg, seed, label, partyU, partyV, |
| 143 | randomSize * 8, random, NULL, FALSE)); |
| 144 | } |