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authorLibravatar vnugent <public@vaughnnugent.com>2024-05-04 14:06:06 -0400
committerLibravatar vnugent <public@vaughnnugent.com>2024-05-04 14:06:06 -0400
commite7375560d465f6da71aae0483c0e7a72535ccc10 (patch)
treebbdfcb275ec0b66cfe84b7f8024258eef6c7aa5a /src/crypto
parent7485aa5a43476c47d54ec51fb96751a14e0ed629 (diff)
Squashed commit of the following:
commit 0a40e209d03e8ff9b6f81cd5969d3e845c633bfc Author: vnugent <public@vaughnnugent.com> Date: Sat May 4 13:55:19 2024 -0400 ci: Force disable testing for win ci builds commit 55fae189fffc86f07a3448370f0a746670819712 Author: vnugent <public@vaughnnugent.com> Date: Thu May 2 21:54:35 2024 -0400 feat: Working and tested openssl impl & defaults commit 6ff8bb11774c51fd341b7699a3938fd894995fbf Author: vnugent <public@vaughnnugent.com> Date: Thu Apr 25 17:45:42 2024 -0400 refactor: Finish support and testing for mbedtls commit 7cb7a93de4f6f5e741bc5129e3d928e44f050930 Author: vnugent <public@vaughnnugent.com> Date: Tue Apr 23 18:19:31 2024 -0400 refactor!: MbedTLS on Windows, switch to uint32 commit 30e8dda6cbea86bdee6d5dfe48514385d3b9f81b Author: vnugent <public@vaughnnugent.com> Date: Tue Apr 23 14:48:05 2024 -0400 refactor: Crypto dep redesign working on Windows commit d09c6c1bd5da3e2d79351daeba304ca99976a726 Author: vnugent <public@vaughnnugent.com> Date: Thu Apr 18 00:28:51 2024 -0400 refactor!: Pushing what I have to dev commit 54e06ada7d624ed0d28c6a6db04a149708841bf8 Author: vnugent <public@vaughnnugent.com> Date: Sat Apr 13 01:24:00 2024 -0400 fix: convert constants to hex, inline macro, ParseErrorCode commit 4215e3100d9a0d23119080d09638fa5b60d0c6d4 Merge: d3328f4 7485aa5 Author: vnugent <public@vaughnnugent.com> Date: Wed Apr 3 18:26:30 2024 -0400 Merge branch 'master' into develop commit d3328f4152b22b28f24c43dda62464287f1efff5 Author: vnugent <public@vaughnnugent.com> Date: Wed Apr 3 18:22:56 2024 -0400 build: Included dependency and versions in client builds commit b11bc0bac955fd5c6db65f0da48456bf5e748805 Author: vnugent <public@vaughnnugent.com> Date: Wed Apr 3 18:10:08 2024 -0400 fix: Fix c89 compatabilty comments and struct assignment commit 9915bd41799a72413e6b400e150aa9f5fa797e25 Merge: 8e3d6ea 5184d7d Author: vnugent <public@vaughnnugent.com> Date: Sat Mar 30 09:57:30 2024 -0400 Merge branch 'master' into develop commit 8e3d6ea5e3c83fe42cb904b6ccc4fe2b73f76aae Author: vnugent <public@vaughnnugent.com> Date: Sat Mar 30 09:52:55 2024 -0400 refactor!: Some api (struct) changes and updated tests commit e88e8420520204e20802516f01d4488bb0b1d6ea Merge: 490dfee 21f6c0a Author: vnugent <public@vaughnnugent.com> Date: Sun Mar 3 15:02:34 2024 -0500 Merge branch 'master' into develop commit 490dfee4ef22479009627435c6ad728c3cbbab54 Author: vnugent <public@vaughnnugent.com> Date: Sun Mar 3 14:59:25 2024 -0500 test: #3 tests for encryption/description and Macs commit efa97490b7ed47f4e2f05bee52e2b33e14e439e6 Merge: 1b84e3c 120022a Author: vnugent <public@vaughnnugent.com> Date: Sun Mar 3 14:55:48 2024 -0500 merge master commit 1b84e3c7c2e55b1ff9ffdd09b66873e11c131441 Author: vnugent <public@vaughnnugent.com> Date: Sat Mar 2 22:57:36 2024 -0500 fix: #2 constent usage of sizeof() operator on struct types commit 9de5a214c66adea0ef2d0bac63c59449de202a88 Author: vnugent <public@vaughnnugent.com> Date: Fri Mar 1 14:30:36 2024 -0500 perf: avoid nc_key struct copy, cast and verify instead commit b917b761120ed684af28d0707673ffadcf14b8fe Author: vnugent <public@vaughnnugent.com> Date: Mon Feb 12 22:06:50 2024 -0500 fix: found the constant time memcompare function commit 9f85fff3b9f25da7410569ea94f994b88feb3910 Author: vnugent <public@vaughnnugent.com> Date: Fri Feb 9 22:48:35 2024 -0500 feat: added/update MAC functions to sign or verify nip44 payload commit aa5113741bb419b02d6ea416bba571fa3d65db46 Author: vnugent <public@vaughnnugent.com> Date: Wed Feb 7 01:37:53 2024 -0500 add missing hmac-key output buffer commit 55f47d22cc9ce4d1e22b70814d608c7ef3b1bbc9 Author: vnugent <public@vaughnnugent.com> Date: Sun Feb 4 21:08:13 2024 -0500 simple bug fixes, and public api argument validation tests commit 73c5a713fb164ae8b4ac8a891a8020e08eae0a3b Author: vnugent <public@vaughnnugent.com> Date: Fri Feb 2 23:05:48 2024 -0500 update api to return secpvalidate return code instead of internal return codes commit 06c73004e1a39a7ea4ea3a89c22dee0f66adb236 Author: vnugent <public@vaughnnugent.com> Date: Fri Feb 2 19:25:17 2024 -0500 change to lgpl license commit 6e79fdb3b6b6739fc7797d47e55a7691306cf736 Author: vnugent <public@vaughnnugent.com> Date: Wed Jan 31 21:30:49 2024 -0500 move validation macros, and optionally disable them commit ac1e58837f1ba687939f78b5c03cadd346c10ddd Author: vnugent <public@vaughnnugent.com> Date: Tue Jan 30 12:25:05 2024 -0500 couple more tests, renable range checks, set flags for all projects
Diffstat (limited to 'src/crypto')
-rw-r--r--src/crypto/hkdf.c131
-rw-r--r--src/crypto/impl/bcrypt.c263
-rw-r--r--src/crypto/impl/mbedtls.c172
-rw-r--r--src/crypto/impl/monocypher.c80
-rw-r--r--src/crypto/impl/openssl.c180
-rw-r--r--src/crypto/nc-crypto.c283
6 files changed, 1109 insertions, 0 deletions
diff --git a/src/crypto/hkdf.c b/src/crypto/hkdf.c
new file mode 100644
index 0000000..0d91d14
--- /dev/null
+++ b/src/crypto/hkdf.c
@@ -0,0 +1,131 @@
+/*
+* Copyright (c) 2024 Vaughn Nugent
+*
+* Package: noscrypt
+* File: hkdf.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/.
+*/
+
+
+#include "hkdf.h"
+
+/* Include string for memmove */
+#include <string.h>
+
+#define HKDF_MIN(a, b) (a < b ? a : b)
+
+STATIC_ASSERT(HKDF_IN_BUF_SIZE > SHA256_DIGEST_SIZE, "HDK Buffer must be at least the size of the underlying hashing alg output")
+
+static _nc_fn_inline void ncWriteSpanS(span_t* span, uint32_t offset, const uint8_t* data, uint32_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 _nc_fn_inline void debugValidateHandler(const struct nc_hkdf_fn_cb_struct* handler)
+{
+ DEBUG_ASSERT(handler != NULL)
+ DEBUG_ASSERT(handler->update != NULL)
+ DEBUG_ASSERT(handler->finish != NULL)
+}
+
+/*
+* The following functions implements the HKDF expand function using an existing
+* HMAC function.
+*
+* This follows the guidence from RFC 5869: https://tools.ietf.org/html/rfc5869
+*/
+
+cstatus_t hkdfExpandProcess(
+ const struct nc_hkdf_fn_cb_struct* handler,
+ void* ctx,
+ const cspan_t* info,
+ span_t* okm
+)
+{
+ cstatus_t result;
+
+ uint8_t counter;
+ uint32_t tLen, okmOffset;
+ uint8_t t[HKDF_IN_BUF_SIZE];
+ cspan_t tSpan, counterSpan;
+
+ debugValidateHandler(handler);
+
+ ncCryptoSecureZero(t, sizeof(t));
+
+ tLen = 0; /* T(0) is an empty string(zero length) */
+ okmOffset = 0;
+ counter = 1; /* counter is offset by 1 for init */
+ result = CSTATUS_FAIL; /* Start in fail state */
+
+ /* counter as a span */
+ ncSpanInitC(&counterSpan, &counter, sizeof(counter));
+
+ /* Compute T(N) = HMAC(prk, T(n-1) | info | n) */
+ while (okmOffset < okm->size)
+ {
+ ncSpanInitC(&tSpan, t, tLen);
+
+ if (handler->update(ctx, &tSpan) != CSTATUS_OK)
+ {
+ goto Exit;
+ }
+
+ if (handler->update(ctx, info) != CSTATUS_OK)
+ {
+ goto Exit;
+ }
+
+ if (handler->update(ctx, &counterSpan) != CSTATUS_OK)
+ {
+ goto Exit;
+ }
+
+ /*
+ * Write current hash state to t buffer. It is known
+ * that the t buffer must be at least the size of the
+ * underlying hash function output.
+ */
+ if (handler->finish(ctx, t) != CSTATUS_OK)
+ {
+ goto Exit;
+ }
+
+ /* tlen becomes the hash size or remaining okm size */
+ tLen = HKDF_MIN(okm->size - okmOffset, SHA256_DIGEST_SIZE);
+
+ DEBUG_ASSERT(tLen <= sizeof(t));
+
+ /* write the T buffer back to okm */
+ ncWriteSpanS(okm, okmOffset, t, tLen);
+
+ /* shift base okm pointer by T */
+ okmOffset += tLen;
+
+ /* increment counter */
+ counter++;
+ }
+
+ result = CSTATUS_OK; /* HMAC operation completed, so set success */
+
+Exit:
+
+ return result;
+}
diff --git a/src/crypto/impl/bcrypt.c b/src/crypto/impl/bcrypt.c
new file mode 100644
index 0000000..9b01cac
--- /dev/null
+++ b/src/crypto/impl/bcrypt.c
@@ -0,0 +1,263 @@
+/*
+* 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 <Windows.h>
+#include <bcrypt.h>
+
+#include "nc-util.h"
+#include "hkdf.h"
+
+#define IF_BC_FAIL(x) if(!BCRYPT_SUCCESS(x))
+#define BC_FAIL(x) if(!BCRYPT_SUCCESS(x)) return CSTATUS_FAIL;
+
+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 update object buffer. By setting
+ * the update 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, uint32_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 update 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 _bcrypt_fallback_hkdf_expand
+
+ cstatus_t _bcrypt_hkdf_update(void* ctx, const cspan_t* data)
+ {
+ DEBUG_ASSERT(ctx != NULL)
+
+ BC_FAIL(_bcHashData((struct _bcrypt_ctx*)ctx, data))
+ return CSTATUS_OK;
+ }
+
+ cstatus_t _bcrypt_hkdf_finish(void* ctx, sha256_t hmacOut32)
+ {
+ DEBUG_ASSERT(ctx != NULL)
+
+ BC_FAIL(_bcFinishHash((struct _bcrypt_ctx*)ctx, hmacOut32))
+ return CSTATUS_OK;
+ }
+
+ _IMPLSTB cstatus_t _bcrypt_fallback_hkdf_expand(const cspan_t* prk, const cspan_t* info, span_t* okm)
+ {
+ cstatus_t result;
+ struct _bcrypt_ctx ctx;
+ struct nc_hkdf_fn_cb_struct handler;
+
+ handler.update = _bcrypt_hkdf_update;
+ handler.finish = _bcrypt_hkdf_finish;
+
+ /* Init bcrypt */
+ BC_FAIL(_bcInitSha256(&ctx, BCRYPT_ALG_HANDLE_HMAC_FLAG))
+
+ BC_FAIL(_bcCreateHmac(&ctx, prk))
+
+ /*
+ * NOTE! Hmac reusable flag must be set to allow for multiple
+ * calls to the finish function without losing the context.
+ */
+
+ result = hkdfExpandProcess(&handler, &ctx, info, okm);
+
+ _bcDestroyCtx(&ctx);
+
+ return result;
+ }
+
+#endif /* !_IMPL_CRYPTO_SHA256_HKDF_EXPAND */
+
+#endif /* _NC_IS_WINDOWS */ \ No newline at end of file
diff --git a/src/crypto/impl/mbedtls.c b/src/crypto/impl/mbedtls.c
new file mode 100644
index 0000000..057e7b4
--- /dev/null
+++ b/src/crypto/impl/mbedtls.c
@@ -0,0 +1,172 @@
+/*
+* Copyright (c) 2024 Vaughn Nugent
+*
+* Package: noscrypt
+* File: mbedtls.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 contains implemntation functions for the required
+* cryptography primitives of noscrypt. This file stubs functionality
+* using the Mbed-TLS library, if the builder desires to link against
+* it.
+*/
+
+#ifdef MBEDTLS_CRYPTO_LIB
+
+/* Inline errors on linux in header files on linux */
+#ifndef inline
+ #define inline __inline
+#endif
+
+#include <mbedtls/md.h>
+#include <mbedtls/hkdf.h>
+#include <mbedtls/hmac_drbg.h>
+#include <mbedtls/sha256.h>
+#include <mbedtls/chacha20.h>
+#include <mbedtls/constant_time.h>
+
+#ifndef inline
+ #undef inline
+#endif
+
+
+_IMPLSTB const mbedtls_md_info_t* _mbed_sha256_alg(void)
+{
+ const mbedtls_md_info_t* info;
+ /* Get sha256 md info for hdkf operations */
+ info = mbedtls_md_info_from_type(MBEDTLS_MD_SHA256);
+ DEBUG_ASSERT2(info != NULL, "Expected SHA256 md info pointer to be valid")
+ return info;
+}
+
+#if SIZE_MAX < UINT64_MAX
+ #define _ssize_guard_int(x) if(x > SIZE_MAX) return 1;
+#else
+ #define _ssize_guard_int(x)
+#endif
+
+#ifndef _IMPL_CHACHA20_CRYPT
+
+ /* Export chacha20 computation */
+ #define _IMPL_CHACHA20_CRYPT _mbed_chacha20_encrypt
+
+ _IMPLSTB cstatus_t _mbed_chacha20_encrypt(
+ const uint8_t* key,
+ const uint8_t* nonce,
+ const uint8_t* input,
+ uint8_t* output,
+ uint32_t dataLen
+ )
+ {
+ _overflow_check(dataLen)
+
+ /* Counter always starts at 0 */
+ return mbedtls_chacha20_crypt(
+ key,
+ nonce,
+ 0x00u, /* nip-44 counter version */
+ dataLen,
+ input,
+ output
+ ) == 0 ? CSTATUS_OK : CSTATUS_FAIL;
+ }
+
+#endif
+
+/* Export sha256 if not already defined */
+#ifndef _IMPL_CRYPTO_SHA256_DIGEST
+
+ #define _IMPL_CRYPTO_SHA256_DIGEST _mbed_sha256_digest
+
+ _IMPLSTB cstatus_t _mbed_sha256_digest(const cspan_t* data, sha256_t digestOut32)
+ {
+ _overflow_check(data->size)
+
+ return mbedtls_sha256(
+ data->data,
+ data->size,
+ digestOut32,
+ 0 /* Set 0 for sha256 mode */
+ ) == 0 ? CSTATUS_OK : CSTATUS_FAIL;
+ }
+
+#endif
+
+/* Export Sha256 hmac if not already defined by other libs */
+#ifndef _IMPL_CRYPTO_SHA256_HMAC
+
+ #define _IMPL_CRYPTO_SHA256_HMAC _mbed_sha256_hmac
+
+ _IMPLSTB cstatus_t _mbed_sha256_hmac(const cspan_t* key, const cspan_t* data, sha256_t hmacOut32)
+ {
+ _overflow_check(data->size)
+
+ /* Keys should never be large enough for this to matter, but sanity check. */
+ DEBUG_ASSERT2(key->size < SIZE_MAX, "Expected key size to be less than SIZE_MAX")
+
+ return mbedtls_md_hmac(
+ _mbed_sha256_alg(),
+ key->data,
+ key->size,
+ data->data,
+ data->size,
+ hmacOut32
+ ) == 0 ? CSTATUS_OK : CSTATUS_FAIL;
+ }
+#endif
+
+/* Export hkdf expand if not already defined */
+#ifndef _IMPL_CRYPTO_SHA256_HKDF_EXPAND
+
+ #define _IMPL_CRYPTO_SHA256_HKDF_EXPAND _mbed_sha256_hkdf_expand
+
+ _IMPLSTB cstatus_t _mbed_sha256_hkdf_expand(const cspan_t* prk, const cspan_t* info, span_t* okm)
+ {
+ /* These sizes should never be large enough to overflow on <64bit platforms, but sanity check */
+ DEBUG_ASSERT(okm->size < SIZE_MAX)
+ DEBUG_ASSERT(prk->size < SIZE_MAX)
+ DEBUG_ASSERT(info->size < SIZE_MAX)
+
+ return mbedtls_hkdf_expand(
+ _mbed_sha256_alg(),
+ prk->data,
+ prk->size,
+ info->data,
+ info->size,
+ okm->data,
+ okm->size
+ ) == 0 ? CSTATUS_OK : CSTATUS_FAIL;
+ }
+
+#endif
+
+/* Export fixed-time compare if not already defined */
+#ifndef _IMPL_CRYPTO_FIXED_TIME_COMPARE
+
+ #define _IMPL_CRYPTO_FIXED_TIME_COMPARE _mbed_fixed_time_compare
+
+ /* fixed-time memcmp */
+ _IMPLSTB uint32_t _mbed_fixed_time_compare(const uint8_t* a, const uint8_t* b, uint32_t size)
+ {
+ _ssize_guard_int(size)
+
+ return (uint32_t)mbedtls_ct_memcmp(a, b, size);
+ }
+#endif
+
+#endif \ No newline at end of file
diff --git a/src/crypto/impl/monocypher.c b/src/crypto/impl/monocypher.c
new file mode 100644
index 0000000..7c9faea
--- /dev/null
+++ b/src/crypto/impl/monocypher.c
@@ -0,0 +1,80 @@
+/*
+* Copyright (c) 2024 Vaughn Nugent
+*
+* Package: noscrypt
+* File: impl/monocypher.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 handles some fallbacks that may not be available on
+* some platforms. More specifically:
+* - Secure memset 0
+* - Chacha20 cipher
+*
+*/
+
+#ifdef NC_ENABLE_MONOCYPHER
+
+#include <monocypher.h>
+
+#include "nc-util.h"
+
+/* Export secure memse0 */
+#ifndef _IMPL_SECURE_ZERO_MEMSET
+
+ /* export cytpo wipe function as is */
+ #define _IMPL_SECURE_ZERO_MEMSET crypto_wipe
+#endif
+
+/* Export Chacha20 */
+#ifndef _IMPL_CHACHA20_CRYPT
+
+ #define _IMPL_CHACHA20_CRYPT _mc_chacha20_crypt
+
+ _IMPLSTB cstatus_t _mc_chacha20_crypt(
+ const uint8_t* key,
+ const uint8_t* nonce,
+ const uint8_t* input,
+ uint8_t* output,
+ uint32_t dataLen
+ )
+ {
+ _overflow_check(dataLen)
+
+ /*
+ * Function returns the next counter value which is not
+ * needed for noscrypt as encryptions are one-shot, and
+ * require a new nonce for each encryption.
+ *
+ * ITEF function uses a 12byte nonce which is required for
+ * nip-44 compliant encryption.
+ */
+ crypto_chacha20_ietf(
+ output,
+ input,
+ (size_t)dataLen,
+ key,
+ nonce,
+ 0x00 /* Counter always starts at 0 */
+ );
+
+ return CSTATUS_OK;
+ }
+
+#endif
+
+#endif /* !NC_ENABLE_MONOCYPHER */ \ No newline at end of file
diff --git a/src/crypto/impl/openssl.c b/src/crypto/impl/openssl.c
new file mode 100644
index 0000000..fd3b4e6
--- /dev/null
+++ b/src/crypto/impl/openssl.c
@@ -0,0 +1,180 @@
+/*
+* Copyright (c) 2024 Vaughn Nugent
+*
+* Package: noscrypt
+* File: impl/openssl.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/.
+*/
+
+
+/* Setup openssl */
+#ifdef OPENSSL_CRYPTO_LIB
+
+#include "nc-util.h"
+#include <openssl/crypto.h>
+
+#define _OSSL_FAIL(x) if(!(x)) return CSTATUS_FAIL;
+
+#ifndef _IMPL_SECURE_ZERO_MEMSET
+
+ #define _IMPL_SECURE_ZERO_MEMSET _ossl_secure_zero_memset
+
+ _IMPLSTB void _ossl_secure_zero_memset(void* ptr, size_t size)
+ {
+ _overflow_check(size)
+
+ OPENSSL_cleanse(ptr, size);
+ }
+#endif
+
+#ifndef _IMPL_CRYPTO_FIXED_TIME_COMPARE
+
+ #define _IMPL_CRYPTO_FIXED_TIME_COMPARE _ossl_fixed_time_compare
+
+ _IMPLSTB uint32_t _ossl_fixed_time_compare(const uint8_t* a, const uint8_t* b, uint32_t size)
+ {
+ int result;
+
+ /* Size checks are required for platforms that have integer sizes under 32bit */
+ _overflow_check(size)
+
+ result = CRYPTO_memcmp(a, b, size);
+
+ return (uint32_t)result;
+ }
+
+#endif /* _IMPL_CRYPTO_FIXED_TIME_COMPARE */
+
+
+#ifndef _IMPL_CRYPTO_SHA256_DIGEST
+
+ #include <openssl/sha.h>
+
+ #define _IMPL_CRYPTO_SHA256_DIGEST _ossl_sha256_digest
+
+ _IMPLSTB cstatus_t _ossl_sha256_digest(const cspan_t* data, sha256_t digestOut32)
+ {
+ _overflow_check(data->size)
+
+ _OSSL_FAIL(SHA256(data->data, data->size, digestOut32))
+
+ return CSTATUS_OK;
+ }
+
+#endif
+
+#ifndef _IMPL_CRYPTO_SHA256_HMAC
+
+ #include <openssl/hmac.h>
+
+ /* Export function */
+ #define _IMPL_CRYPTO_SHA256_HMAC _ossl_hmac_sha256
+
+ _IMPLSTB cstatus_t _ossl_hmac_sha256(const cspan_t* key, const cspan_t* data, sha256_t hmacOut32)
+ {
+ unsigned int hmacLen;
+
+ _overflow_check(key->size)
+ _overflow_check(data->size)
+
+ hmacLen = sizeof(sha256_t);
+
+ _OSSL_FAIL(
+ HMAC(
+ EVP_sha256(),
+ key->data,
+ key->size,
+ data->data,
+ data->size,
+ hmacOut32,
+ &hmacLen
+ )
+ )
+
+ /* digest length should match the actual digest size */
+ DEBUG_ASSERT(hmacLen == sizeof(sha256_t))
+
+ return CSTATUS_OK;
+ }
+
+#endif /* !_IMPL_CRYPTO_SHA256_HMAC */
+
+#ifndef _IMPL_CRYPTO_SHA256_HKDF_EXPAND
+
+ #include <openssl/hmac.h>
+ #include "hkdf.h"
+
+ #define _IMPL_CRYPTO_SHA256_HKDF_EXPAND _ossl_sha256_hkdf_expand
+
+ cstatus_t _ossl_hkdf_update(void* ctx, const cspan_t* data)
+ {
+ DEBUG_ASSERT(ctx != NULL)
+
+ _overflow_check(data->size)
+
+ _OSSL_FAIL(EVP_DigestUpdate((EVP_MD_CTX*)ctx, data->data, data->size))
+
+ return CSTATUS_OK;
+ }
+
+ cstatus_t _ossl_hkdf_finish(void* ctx, sha256_t hmacOut32)
+ {
+ unsigned int hmacSize;
+
+ DEBUG_ASSERT(ctx != NULL)
+
+ hmacSize = sizeof(sha256_t);
+
+ _OSSL_FAIL(EVP_DigestFinal_ex((EVP_MD_CTX*)ctx, hmacOut32, &hmacSize))
+
+ /* When configured for sha256, should always be the same size in/out */
+ DEBUG_ASSERT(hmacSize == sizeof(sha256_t))
+
+ return CSTATUS_OK;
+ }
+
+ _IMPLSTB cstatus_t _ossl_sha256_hkdf_expand(const cspan_t* prk, const cspan_t* info, span_t* okm)
+ {
+ EVP_MD_CTX* ctx;
+ cstatus_t result;
+ struct nc_hkdf_fn_cb_struct handler;
+
+ /*
+ * NOTE! Hmac reusable flag must be set to allow for multiple
+ * calls to the finish function without losing the context.
+ */
+
+ if ((ctx = EVP_MD_CTX_create()) == NULL)
+ {
+ return CSTATUS_FAIL;
+ }
+
+ _OSSL_FAIL(EVP_DigestInit_ex2(ctx, EVP_sha256(), NULL))
+
+ _OSSL_FAIL(EVP_DigestUpdate(ctx, prk->data, prk->size));
+
+ handler.update = _ossl_hkdf_update;
+ handler.finish = _ossl_hkdf_finish;
+
+ result = hkdfExpandProcess(&handler, ctx, info, okm);
+
+ EVP_MD_CTX_destroy(ctx);
+
+ return result;
+ }
+
+#endif /* !_IMPL_CRYPTO_SHA256_HKDF_EXPAND */
+
+#endif /*!OPENSSL_CRYPTO_LIB */ \ No newline at end of file
diff --git a/src/crypto/nc-crypto.c b/src/crypto/nc-crypto.c
new file mode 100644
index 0000000..587d59d
--- /dev/null
+++ b/src/crypto/nc-crypto.c
@@ -0,0 +1,283 @@
+/*
+* Copyright (c) 2024 Vaughn Nugent
+*
+* Package: noscrypt
+* File: nc-crypto.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/.
+*/
+
+#include "nc-util.h"
+#include "nc-crypto.h"
+
+/*
+* Functions are not forced inline, just suggested.
+* So unless it becomes a performance issue, I will leave
+* most/all impl functions inline and let the compiler
+* decide.
+*/
+
+#define _IMPLSTB static _nc_fn_inline
+
+/*
+* Impl .c files may define the following macros for function implementations:
+*
+* _IMPL_SECURE_ZERO_MEMSET secure memset 0 function
+* _IMPL_CHACHA20_CRYPT chacha20 cipher function
+* _IMPL_CRYPTO_FIXED_TIME_COMPARE fixed time compare function
+* _IMPL_CRYPTO_SHA256_HMAC sha256 hmac function
+* _IMPL_CRYPTO_SHA256_DIGEST standard sha256 digest function
+* _IMPL_CRYPTO_SHA256_HKDF_EXPAND hkdf expand function
+* _IMPL_CRYPTO_SHA256_HKDF_EXTRACT hkdf extract function
+*
+* Macros are used to allow the preprocessor to select the correct implementation
+* or raise errors if no implementation is defined.
+*
+* Implementation functions can assume inputs have been checked/sanitized by the
+* calling function, and should return CSTATUS_OK on success, CSTATUS_FAIL on failure.
+*/
+
+
+/*
+* Prioritize embedded builds with mbedtls
+*/
+#include "impl/mbedtls.c"
+
+/*
+* Include openssl as an alternative default
+* implementation
+*/
+#include "impl/openssl.c"
+
+/*
+* Include win32 platform specific fallback support
+* using bcrypt.
+*/
+#include "impl/bcrypt.c"
+
+/*
+* Handle default implementations of secure
+* memset 0 functions for each platform.
+*/
+#ifndef _IMPL_SECURE_ZERO_MEMSET
+ /* only incude bzero if libc version greater than 2.25 */
+ #if defined(__GLIBC__) && defined(__GLIBC_MINOR__) && __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 25
+ /*
+ * When using libc, we can use explicit_bzero
+ * as secure memset implementation.
+ *
+ * https://sourceware.org/glibc/manual/2.39/html_mono/libc.html#Erasing-Sensitive-Data
+ */
+ #include <string.h>
+ extern void explicit_bzero(void* block, size_t len);
+ #define _IMPL_SECURE_ZERO_MEMSET explicit_bzero
+ #endif
+#endif
+
+/*
+* Finally fall back to monocipher to handle some
+* that are not provided by other libraries.
+*
+* Platform specific opimizations are considered
+* "better" than monocypher options, so this is
+* added as a last resort. Momocypher is "correct"
+* and portable, but not optimized for any specific
+* platform.
+*/
+#include "impl/monocypher.c"
+
+
+#ifdef _IMPL_CRYPTO_SHA256_HMAC
+
+ /*
+ * If a library does not provide a HKDF extract function,
+ * we can just use the HMAC function as a fallback.
+ *
+ * This is a fallback because another library may provide
+ * a more optimized implementation.
+ */
+
+ #ifndef _IMPL_CRYPTO_SHA256_HKDF_EXTRACT
+
+ #define _IMPL_CRYPTO_SHA256_HKDF_EXTRACT _fallbackHkdfExtract
+
+ _IMPLSTB cstatus_t _fallbackHkdfExtract(const cspan_t* salt, const cspan_t* ikm, sha256_t prk)
+ {
+ return _IMPL_CRYPTO_SHA256_HMAC(salt, ikm, prk);
+ }
+
+ #endif /* !_IMPL_CRYPTO_SHA256_HKDF_EXTRACT */
+
+#endif /* _IMPL_CRYPTO_SHA256_HMAC */
+
+/* Fallback for fixed time comparison for all platforms */
+#ifndef _IMPL_CRYPTO_FIXED_TIME_COMPARE
+
+ #pragma message("Warning: No fixed time compare implementation defined, using fallback. This may not be secure on all platforms")
+
+ #define _IMPL_CRYPTO_FIXED_TIME_COMPARE _fallbackFixedTimeCompare
+
+ /*
+ * This implemntation is a slightly simplified version of
+ * MBed TLS constant time memcmp function, knowm to be a 32bit
+ * integer size
+ */
+
+ static uint32_t _fallbackFixedTimeCompare(const uint8_t* a, const uint8_t* b, uint32_t size)
+ {
+ size_t i;
+ uint32_t result;
+ uint8_t O;
+ volatile const uint8_t* A, * B;
+
+ result = 0;
+ O = 0;
+ A = (volatile const uint8_t*)a;
+ B = (volatile const uint8_t*)b;
+
+ /* Compare each byte */
+ for(i = 0; i < size; i++)
+ {
+ /* Handle volatile read */
+ O |= (A[i] ^ B[i]);
+
+ result |= O;
+ }
+
+ return result;
+ }
+
+#endif /* !_IMPL_CRYPTO_FIXED_TIME_COMPARE */
+
+
+/*
+* Internal function implementations that perform
+* basic checking and call the correct implementation
+* for the desired crypto impl.
+*
+* The following functions MUST be assumed to
+* perform basic input validation. Since these apis are
+* internal, debug asserts are used to ensure the
+* function has been used correctly.
+*/
+
+void ncCryptoSecureZero(void* ptr, uint32_t size)
+{
+ DEBUG_ASSERT2(ptr != NULL, "Expected ptr to be non-null")
+
+#ifndef _IMPL_SECURE_ZERO_MEMSET
+ #error "No secure memset implementation defined"
+#endif /* _IMPL_SECURE_ZERO_MEMSET */
+
+ _IMPL_SECURE_ZERO_MEMSET(ptr, size);
+}
+
+uint32_t ncCryptoFixedTimeComp(const uint8_t* a, const uint8_t* b, uint32_t size)
+{
+ DEBUG_ASSERT2(a != NULL, "Expected a to be non-null")
+ DEBUG_ASSERT2(b != NULL, "Expected b to be non-null")
+
+#ifndef _IMPL_CRYPTO_FIXED_TIME_COMPARE
+ #error "No fixed time compare implementation defined"
+#endif /* !_IMPL_CRYPTO_FIXED_TIME_COMPARE */
+
+ return _IMPL_CRYPTO_FIXED_TIME_COMPARE(a, b, size);
+}
+
+cstatus_t ncCryptoDigestSha256(const cspan_t* data, sha256_t digestOut32)
+{
+ /* Debug arg validate */
+ DEBUG_ASSERT2(data != NULL && data->data != NULL, "Expected data to be non-null")
+ DEBUG_ASSERT2(digestOut32 != NULL, "Expected digestOut32 to be non-null")
+
+#ifndef _IMPL_CRYPTO_SHA256_DIGEST
+ #error "No SHA256 implementation defined"
+#endif /* !_IMPL_CRYPTO_SHA256_DIGEST */
+
+ return _IMPL_CRYPTO_SHA256_DIGEST(data, digestOut32);
+}
+
+cstatus_t ncCryptoHmacSha256(const cspan_t* key, const cspan_t* data, sha256_t hmacOut32)
+{
+ /* Debug arg validate */
+ DEBUG_ASSERT2(key != NULL && key->data != NULL, "Expected key to be non-null")
+ DEBUG_ASSERT2(data != NULL && data->data != NULL, "Expected data to be non-null")
+ DEBUG_ASSERT2(hmacOut32 != NULL && data->data != NULL, "Expected hmacOut32 to be non-null")
+
+#ifndef _IMPL_CRYPTO_SHA256_HMAC
+ #error "No SHA256 HMAC implementation defined"
+#endif /* !_IMPL_CRYPTO_SHA256_HMAC */
+
+ return _IMPL_CRYPTO_SHA256_HMAC(key, data, hmacOut32);
+}
+
+cstatus_t ncCryptoSha256HkdfExpand(const cspan_t* prk, const cspan_t* info, span_t* okm)
+{
+ /* Debug arg validate */
+ DEBUG_ASSERT2(prk != NULL && prk->data != NULL, "Expected prk to be non-null")
+ DEBUG_ASSERT2(info != NULL && info->data != NULL, "Expected info to be non-null")
+ DEBUG_ASSERT2(okm != NULL && okm->data != NULL, "Expected okm to be non-null")
+
+ /*
+ * RFC 5869: 2.3
+ * "length of output keying material in octets (<= 255 * HashLen)"
+ *
+ * important as the counter is 1 byte, so it cannot overflow
+ */
+
+ if(okm->size > (uint32_t)(0xFFu * SHA256_DIGEST_SIZE))
+ {
+ return CSTATUS_FAIL;
+ }
+
+#ifndef _IMPL_CRYPTO_SHA256_HKDF_EXPAND
+ #error "No SHA256 HKDF expand implementation defined"
+#endif /* !_IMPL_CRYPTO_SHA256_HKDF_EXPAND */
+
+ return _IMPL_CRYPTO_SHA256_HKDF_EXPAND(prk, info, okm);
+}
+
+cstatus_t ncCryptoSha256HkdfExtract(const cspan_t* salt, const cspan_t* ikm, sha256_t prk)
+{
+ /* Debug arg validate */
+ DEBUG_ASSERT2(salt != NULL, "Expected salt to be non-null")
+ DEBUG_ASSERT2(ikm != NULL, "Expected ikm to be non-null")
+ DEBUG_ASSERT2(prk != NULL, "Expected prk to be non-null")
+
+#ifndef _IMPL_CRYPTO_SHA256_HKDF_EXTRACT
+ #error "No SHA256 HKDF extract implementation defined"
+#endif /* !_IMPL_CRYPTO_SHA256_HKDF_EXTRACT */
+
+ return _IMPL_CRYPTO_SHA256_HKDF_EXTRACT(salt, ikm, prk);
+}
+
+cstatus_t ncCryptoChacha20(
+ const uint8_t key[CHACHA_KEY_SIZE],
+ const uint8_t nonce[CHACHA_NONCE_SIZE],
+ const uint8_t* input,
+ uint8_t* output,
+ uint32_t dataSize
+)
+{
+ DEBUG_ASSERT2(key != NULL, "Expected key to be non-null")
+ DEBUG_ASSERT2(nonce != NULL, "Expected nonce to be non-null")
+ DEBUG_ASSERT2(input != NULL, "Expected input to be non-null")
+ DEBUG_ASSERT2(output != NULL, "Expected output to be non-null")
+
+#ifndef _IMPL_CHACHA20_CRYPT
+ #error "No chacha20 implementation defined"
+#endif /* !_IMPL_CHACHA20_CRYPT */
+
+ return _IMPL_CHACHA20_CRYPT(key, nonce, input, output, dataSize);
+}