From 7cb7a93de4f6f5e741bc5129e3d928e44f050930 Mon Sep 17 00:00:00 2001 From: vnugent Date: Tue, 23 Apr 2024 18:19:31 -0400 Subject: refactor!: MbedTLS on Windows, switch to uint32 --- src/internal/impl/bcrypt.c | 297 --------------------------------------------- 1 file changed, 297 deletions(-) delete mode 100644 src/internal/impl/bcrypt.c (limited to 'src/internal/impl/bcrypt.c') diff --git a/src/internal/impl/bcrypt.c b/src/internal/impl/bcrypt.c deleted file mode 100644 index 8ae6c5a..0000000 --- a/src/internal/impl/bcrypt.c +++ /dev/null @@ -1,297 +0,0 @@ -/* -* Copyright (c) 2024 Vaughn Nugent -* -* Package: noscrypt -* File: impl/bcrypt.c -* -* This library is free software; you can redistribute it and/or -* modify it under the terms of the GNU Lesser General Public License -* as published by the Free Software Foundation; either version 2.1 -* of the License, or (at your option) any later version. -* -* This library is distributed in the hope that it will be useful, -* but WITHOUT ANY WARRANTY; without even the implied warranty of -* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU -* Lesser General Public License for more details. -* -* You should have received a copy of the GNU Lesser General Public License -* along with noscrypt. If not, see http://www.gnu.org/licenses/. -*/ - - -/* -* This file provides as many fallback implementations on Windows plaforms -* as possible using the bcrypt library. This file should be included behind -* other libarry implementations, as it is a fallback. -*/ - -#ifdef _NC_IS_WINDOWS - -#define WIN32_LEAN_AND_MEAN -#include -#include - -#include "../../platform.h" -#include "../nc-util.h" - -#define IF_BC_FAIL(x) if(!BCRYPT_SUCCESS(x)) - -struct _bcrypt_ctx -{ - BCRYPT_ALG_HANDLE hAlg; - BCRYPT_HASH_HANDLE hHash; -}; - -_IMPLSTB NTSTATUS _bcInitSha256(struct _bcrypt_ctx* ctx, DWORD flags) -{ - NTSTATUS result; - - result = BCryptOpenAlgorithmProvider( - &ctx->hAlg, - BCRYPT_SHA256_ALGORITHM, - NULL, - flags - ); - - /* - * If operation failed, ensure the algorithm handle is null - * to make free code easier to cleanup - */ - if (!BCRYPT_SUCCESS(result)) - { - ctx->hAlg = NULL; - } - - return result; -} - -_IMPLSTB NTSTATUS _bcCreateHmac(struct _bcrypt_ctx* ctx, const cspan_t* key) -{ - /* - * NOTE: - * I am not explicitly managing the hash object buffer. By setting - * the hash object to NULL, and length to 0, the buffer will be - * managed by the bcrypt library. - * - * See: https://learn.microsoft.com/en-us/windows/win32/api/bcrypt/nf-bcrypt-bcryptcreatehash - */ - - return BCryptCreateHash( - ctx->hAlg, - &ctx->hHash, - NULL, - 0, - (uint8_t*)key->data, - key->size, - BCRYPT_HASH_REUSABLE_FLAG /* Enable reusable for expand function */ - ); -} - -_IMPLSTB NTSTATUS _bcCreate(struct _bcrypt_ctx* ctx) -{ - cspan_t key; - - /* Zero out key span for 0 size and NULL data ptr */ - SecureZeroMemory(&key, sizeof(cspan_t)); - - return _bcCreateHmac(ctx, &key); -} - -_IMPLSTB NTSTATUS _bcHashDataRaw(const struct _bcrypt_ctx* ctx, const uint8_t* data, uint64_t len) -{ - return BCryptHashData(ctx->hHash, (uint8_t*)data, len, 0); -} - -_IMPLSTB NTSTATUS _bcHashData(const struct _bcrypt_ctx* ctx, const cspan_t* data) -{ - return _bcHashDataRaw(ctx, data->data, data->size); -} - -_IMPLSTB NTSTATUS _bcFinishHash(const struct _bcrypt_ctx* ctx, sha256_t digestOut32) -{ - return BCryptFinishHash(ctx->hHash, digestOut32, sizeof(sha256_t), 0); -} - -_IMPLSTB void _bcDestroyCtx(struct _bcrypt_ctx* ctx) -{ - /* Free the hash memory if it was allocated */ - if(ctx->hHash) BCryptDestroyHash(ctx->hHash); - - /* Close the algorithm provider */ - if (ctx->hAlg) BCryptCloseAlgorithmProvider(ctx->hAlg, 0); - - ctx->hAlg = NULL; - ctx->hHash = NULL; -} - -#ifndef _IMPL_SECURE_ZERO_MEMSET - /* - * On Windows, we can use SecureZeroMemory - * as platform zeroing function. - * - * NOTE: - * SecureZeroMemory2 uses volitle function argument - * pointers, which is a contested mehtod of compiler - * optimization prevention. GNU seems to oppose this method - * - * https://learn.microsoft.com/en-us/windows/win32/memory/winbase-securezeromemory2 - */ - #define _IMPL_SECURE_ZERO_MEMSET SecureZeroMemory -#endif /* !_IMPL_SECURE_ZERO_MEMSET */ - -/* -* Provide win32 fallback for sha256 digest if needed -*/ - -#ifndef _IMPL_CRYPTO_SHA256_DIGEST - - /* Export function fallack */ - #define _IMPL_CRYPTO_SHA256_DIGEST _bcrypt_sha256_digest - - _IMPLSTB cstatus_t _bcrypt_sha256_digest(const cspan_t* data, sha256_t digestOut32) - { - cstatus_t result; - struct _bcrypt_ctx ctx; - - result = CSTATUS_FAIL; /* Start in fail state */ - - IF_BC_FAIL(_bcInitSha256(&ctx, 0)) goto Exit; - - IF_BC_FAIL(_bcCreate(&ctx)) goto Exit; - - IF_BC_FAIL(_bcHashData(&ctx, data)) goto Exit; - - IF_BC_FAIL(_bcFinishHash(&ctx, digestOut32)) goto Exit; - - result = CSTATUS_OK; /* Hash operation completed, so set success */ - - Exit: - - _bcDestroyCtx(&ctx); - - return result; - } - -#endif /* !_IMPL_CRYPTO_SHA256_DIGEST */ - -#ifndef _IMPL_CRYPTO_SHA256_HMAC - - /* Export function */ - #define _IMPL_CRYPTO_SHA256_HMAC _bcrypt_hmac_sha256 - - _IMPLSTB cstatus_t _bcrypt_hmac_sha256(const cspan_t* key, const cspan_t* data, sha256_t hmacOut32) - { - cstatus_t result; - struct _bcrypt_ctx ctx; - - result = CSTATUS_FAIL; /* Start in fail state */ - - /* Init context with hmac flag set */ - IF_BC_FAIL(_bcInitSha256(&ctx, BCRYPT_ALG_HANDLE_HMAC_FLAG)) goto Exit; - - IF_BC_FAIL(_bcCreateHmac(&ctx, key)) goto Exit; - - IF_BC_FAIL(_bcHashData(&ctx, data)) goto Exit; - - IF_BC_FAIL(_bcFinishHash(&ctx, hmacOut32)) goto Exit; - - result = CSTATUS_OK; /* HMAC operation completed, so set success */ - - Exit: - - _bcDestroyCtx(&ctx); - - return result; - } - -#endif /* !_IMPL_CRYPTO_SHA256_HMAC */ - -/* -* Provide a fallback HKDF expand function using the -* HMAC function as a base. -*/ - -#ifndef _IMPL_CRYPTO_SHA256_HKDF_EXPAND - - #define _IMPL_CRYPTO_SHA256_HKDF_EXPAND _fallbackHkdfExpand - - /* Include string for memmove */ - #include - - static void ncWriteSpanS(span_t* span, uint64_t offset, const uint8_t* data, uint64_t size) - { - DEBUG_ASSERT2(span != NULL, "Expected span to be non-null") - DEBUG_ASSERT2(data != NULL, "Expected data to be non-null") - DEBUG_ASSERT2(offset + size <= span->size, "Expected offset + size to be less than span size") - - /* Copy data to span */ - memmove(span->data + offset, data, size); - } - - STATIC_ASSERT(HKDF_IN_BUF_SIZE > SHA256_DIGEST_SIZE, "HDK Buffer must be at least the size of the underlying hashing alg output") - - /* - * The following functions implements the HKDF expand function using an existing - * HMAC function. This is a fallback implementation for Windows platforms at the moment. - * - * This follows the guidence from RFC 5869: https://tools.ietf.org/html/rfc5869 - */ - - #define _BC_MIN(a, b) (a < b ? a : b) - - _IMPLSTB cstatus_t _fallbackHkdfExpand(const cspan_t* prk, const cspan_t* info, span_t* okm) - { - cstatus_t result; - struct _bcrypt_ctx ctx; - - uint8_t counter; - uint64_t tLen, okmOffset; - uint8_t t[HKDF_IN_BUF_SIZE]; - - _IMPL_SECURE_ZERO_MEMSET(t, sizeof(t)); - - tLen = 0; /* T(0) is an empty string(zero length) */ - okmOffset = 0; - result = CSTATUS_FAIL; /* Start in fail state */ - - /* Init context with hmac flag set, it will be reused */ - IF_BC_FAIL(_bcInitSha256(&ctx, BCRYPT_ALG_HANDLE_HMAC_FLAG)) goto Exit; - - /* Set hmac key to the prk, alg is set to reusable */ - IF_BC_FAIL(_bcCreateHmac(&ctx, prk)) goto Exit; - - /* Compute T(N) = HMAC(prk, T(n-1) | info | n) */ - for (counter = 1; okmOffset < okm->size; counter++) - { - IF_BC_FAIL(_bcHashDataRaw(&ctx, t, tLen)) goto Exit; - IF_BC_FAIL(_bcHashData(&ctx, info)) goto Exit; - IF_BC_FAIL(_bcHashDataRaw(&ctx, &counter, sizeof(counter))) goto Exit; - - /* Write current hash state to t buffer */ - IF_BC_FAIL(_bcFinishHash(&ctx, t)) goto Exit; - - /* Set the length of the current hash state */ - tLen = _BC_MIN(okm->size - okmOffset, SHA256_DIGEST_SIZE); - - DEBUG_ASSERT(tLen <= sizeof(t)); - DEBUG_ASSERT((tLen + okmOffset) < okm->size); - - /* write the T buffer back to okm */ - ncWriteSpanS(okm, okmOffset, t, tLen); - - /* shift base okm pointer by T */ - okmOffset += tLen; - } - - result = CSTATUS_OK; /* HMAC operation completed, so set success */ - - Exit: - - _bcDestroyCtx(&ctx); - - return result; - } - -#endif /* !_IMPL_CRYPTO_SHA256_HKDF_EXPAND */ - -#endif /* _NC_IS_WINDOWS */ \ No newline at end of file -- cgit