ctrdrbg.h (3048B)
1 // Copyright 2022 The BoringSSL Authors 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // https://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #ifndef OPENSSL_HEADER_CTRDRBG_H 16 #define OPENSSL_HEADER_CTRDRBG_H 17 18 #include <openssl/base.h> // IWYU pragma: export 19 20 #if defined(__cplusplus) 21 extern "C" { 22 #endif 23 24 25 // FIPS pseudo-random number generator. 26 27 28 // CTR-DRBG state objects. 29 // 30 // CTR_DRBG_STATE contains the state of a FIPS AES-CTR-based pseudo-random 31 // number generator. If BoringSSL was built in FIPS mode then this is a FIPS 32 // Approved algorithm. 33 34 // CTR_DRBG_ENTROPY_LEN is the number of bytes of input entropy. See SP 35 // 800-90Ar1, table 3. 36 #define CTR_DRBG_ENTROPY_LEN 48 37 38 // CTR_DRBG_MAX_GENERATE_LENGTH is the maximum number of bytes that can be 39 // generated in a single call to |CTR_DRBG_generate|. 40 #define CTR_DRBG_MAX_GENERATE_LENGTH 65536 41 42 // CTR_DRBG_new returns an initialized |CTR_DRBG_STATE|, or NULL if either 43 // allocation failed or if |personalization_len| is invalid. 44 OPENSSL_EXPORT CTR_DRBG_STATE *CTR_DRBG_new( 45 const uint8_t entropy[CTR_DRBG_ENTROPY_LEN], const uint8_t *personalization, 46 size_t personalization_len); 47 48 // CTR_DRBG_free frees |state| if non-NULL, or else does nothing. 49 OPENSSL_EXPORT void CTR_DRBG_free(CTR_DRBG_STATE* state); 50 51 // CTR_DRBG_reseed reseeds |drbg| given |CTR_DRBG_ENTROPY_LEN| bytes of entropy 52 // in |entropy| and, optionally, up to |CTR_DRBG_ENTROPY_LEN| bytes of 53 // additional data. It returns one on success or zero on error. 54 OPENSSL_EXPORT int CTR_DRBG_reseed(CTR_DRBG_STATE *drbg, 55 const uint8_t entropy[CTR_DRBG_ENTROPY_LEN], 56 const uint8_t *additional_data, 57 size_t additional_data_len); 58 59 // CTR_DRBG_generate processes to up |CTR_DRBG_ENTROPY_LEN| bytes of additional 60 // data (if any) and then writes |out_len| random bytes to |out|, where 61 // |out_len| <= |CTR_DRBG_MAX_GENERATE_LENGTH|. It returns one on success or 62 // zero on error. 63 OPENSSL_EXPORT int CTR_DRBG_generate(CTR_DRBG_STATE *drbg, uint8_t *out, 64 size_t out_len, 65 const uint8_t *additional_data, 66 size_t additional_data_len); 67 68 // CTR_DRBG_clear zeroises the state of |drbg|. 69 OPENSSL_EXPORT void CTR_DRBG_clear(CTR_DRBG_STATE *drbg); 70 71 72 #if defined(__cplusplus) 73 } // extern C 74 75 extern "C++" { 76 BSSL_NAMESPACE_BEGIN 77 BORINGSSL_MAKE_DELETER(CTR_DRBG_STATE, CTR_DRBG_free) 78 BSSL_NAMESPACE_END 79 } // extern C++ 80 #endif 81 82 #endif // OPENSSL_HEADER_CTRDRBG_H