/* * fast-pbkdf2 - Optimal PBKDF2-HMAC calculation * Written in 2015 by Joseph Birr-Pixton * * To the extent possible under law, the author(s) have dedicated all * copyright and related and neighboring rights to this software to the * public domain worldwide. This software is distributed without any * warranty. * * You should have received a copy of the CC0 Public Domain Dedication * along with this software. If not, see * . */ /* librist. Copyright © 2019 SipRadius LLC. All right reserved. * Author: Kuldeep Singh Dhaka * Author: Sergio Ammirata, Ph.D. * * Changes: * - Removed SHA1 and SHA512 as the functions are not available * - Moved to self hosted SHA256 instead of OpenSSL */ #include "fastpbkdf2.h" #include #include #if defined(__linux__) || defined(__GLIBC__) #include #elif defined(__APPLE__) || defined(__GLIBC__) #include #define __LITTLE_ENDIAN __DARWIN_LITTLE_ENDIAN #define __BYTE_ORDER __DARWIN_BYTE_ORDER #elif defined(__FreeBSD__) #include #define __LITTLE_ENDIAN _LITTLE_ENDIAN #define __BYTE_ORDER _BYTE_ORDER #endif /* __MacOS__ */ #include "sha256.h" /* --- MSVC doesn't support C99 --- */ #ifdef _MSC_VER #define restrict #define _Pragma __pragma #endif /* --- Common useful things --- */ #define MIN(a, b) ((a) > (b)) ? (b) : (a) static inline void write32_be(uint32_t n, uint8_t out[4]) { #if defined(__GNUC__) && __GNUC__ >= 4 && __BYTE_ORDER == __LITTLE_ENDIAN *(uint32_t *)(out) = __builtin_bswap32(n); #else out[0] = (n >> 24) & 0xff; out[1] = (n >> 16) & 0xff; out[2] = (n >> 8) & 0xff; out[3] = n & 0xff; #endif } /* * NOTE: This function is unused currently, but it is left incase it is needed in the * future */ /* static inline void write64_be(uint64_t n, uint8_t out[8]) * { * #if defined(__GNUC__) && __GNUC__ >= 4 && __BYTE_ORDER == __LITTLE_ENDIAN * *(uint64_t *)(out) = __builtin_bswap64(n); * #else * write32_be((n >> 32) & 0xffffffff, out); * write32_be(n & 0xffffffff, out + 4); * #endif * } */ /* --- Optional OpenMP parallelisation of consecutive blocks --- */ #ifdef WITH_OPENMP # define OPENMP_PARALLEL_FOR _Pragma("omp parallel for") #else # define OPENMP_PARALLEL_FOR #endif /* Prepare block (of blocksz bytes) to contain md padding denoting a msg-size * message (in bytes). block has a prefix of used bytes. * * Message length is expressed in 32 bits (so suitable for sha1, sha256, sha512). */ static inline void md_pad(uint8_t *block, size_t blocksz, size_t used, size_t msg) { memset(block + used, 0, blocksz - used - 4); block[used] = 0x80; block += blocksz - 4; write32_be((uint32_t) (msg * 8), block); } /* Internal function/type names for hash-specific things. */ #define HMAC_CTX(_name) HMAC_ ## _name ## _ctx #define HMAC_INIT(_name) HMAC_ ## _name ## _init #define HMAC_UPDATE(_name) HMAC_ ## _name ## _update #define HMAC_FINAL(_name) HMAC_ ## _name ## _final #define PBKDF2_F(_name) pbkdf2_f_ ## _name #define PBKDF2(_name) pbkdf2_ ## _name /* This macro expands to decls for the whole implementation for a given * hash function. Arguments are: * * _name like 'sha1', added to symbol names * _blocksz block size, in bytes * _hashsz digest output, in bytes * _ctx hash context type * _init hash context initialisation function * args: (_ctx *c) * _update hash context update function * args: (_ctx *c, const void *data, size_t ndata) * _final hash context finish function * args: (void *out, _ctx *c) * _xform hash context raw block update function * args: (_ctx *c, const void *data) * _xcpy hash context raw copy function (only need copy hash state) * args: (_ctx * restrict out, const _ctx *restrict in) * _xtract hash context state extraction * args: args (_ctx *restrict c, uint8_t *restrict out) * _xxor hash context xor function (only need xor hash state) * args: (_ctx *restrict out, const _ctx *restrict in) * * The resulting function is named PBKDF2(_name). */ #define DECL_PBKDF2(_name, _blocksz, _hashsz, _ctx, \ _init, _update, _xform, _final, _xcpy, _xtract, _xxor) \ typedef struct { \ _ctx inner; \ _ctx outer; \ } HMAC_CTX(_name); \ \ static inline void HMAC_INIT(_name)(HMAC_CTX(_name) *ctx, \ const uint8_t *key, size_t nkey) \ { \ /* Prepare key: */ \ uint8_t k[_blocksz]; \ \ /* Shorten long keys. */ \ if (nkey > _blocksz) \ { \ _init(&ctx->inner); \ _update(&ctx->inner, key, nkey); \ _final(&ctx->inner, k); \ \ key = k; \ nkey = _hashsz; \ } \ \ /* Standard doesn't cover case where blocksz < hashsz. */ \ assert(nkey <= _blocksz); \ \ /* Right zero-pad short keys. */ \ if (k != key) \ memcpy(k, key, nkey); \ if (_blocksz > nkey) \ memset(k + nkey, 0, _blocksz - nkey); \ \ /* Start inner hash computation */ \ uint8_t blk_inner[_blocksz]; \ uint8_t blk_outer[_blocksz]; \ \ for (size_t i = 0; i < _blocksz; i++) \ { \ blk_inner[i] = 0x36 ^ k[i]; \ blk_outer[i] = 0x5c ^ k[i]; \ } \ \ _init(&ctx->inner); \ _update(&ctx->inner, blk_inner, sizeof blk_inner); \ \ /* And outer. */ \ _init(&ctx->outer); \ _update(&ctx->outer, blk_outer, sizeof blk_outer); \ } \ \ static inline void HMAC_UPDATE(_name)(HMAC_CTX(_name) *ctx, \ const void *data, size_t ndata) \ { \ _update(&ctx->inner, data, ndata); \ } \ \ static inline void HMAC_FINAL(_name)(HMAC_CTX(_name) *ctx, \ uint8_t out[_hashsz]) \ { \ _final(&ctx->inner, out); \ _update(&ctx->outer, out, _hashsz); \ _final(&ctx->outer, out); \ } \ \ \ /* --- PBKDF2 --- */ \ static inline void PBKDF2_F(_name)(const HMAC_CTX(_name) *startctx, \ uint32_t counter, \ const uint8_t *salt, size_t nsalt, \ uint32_t iterations, \ uint8_t *out) \ { \ uint8_t countbuf[4]; \ write32_be(counter, countbuf); \ \ /* Prepare loop-invariant padding block. */ \ uint8_t Ublock[_blocksz]; \ md_pad(Ublock, _blocksz, _hashsz, _blocksz + _hashsz); \ \ /* First iteration: \ * U_1 = PRF(P, S || INT_32_BE(i)) \ */ \ HMAC_CTX(_name) ctx = *startctx; \ HMAC_UPDATE(_name)(&ctx, salt, nsalt); \ HMAC_UPDATE(_name)(&ctx, countbuf, sizeof countbuf); \ HMAC_FINAL(_name)(&ctx, Ublock); \ _ctx result = ctx.outer; \ \ /* Subsequent iterations: \ * U_c = PRF(P, U_{c-1}) \ */ \ for (uint32_t i = 1; i < iterations; i++) \ { \ /* Complete inner hash with previous U */ \ _xcpy(&ctx.inner, &startctx->inner); \ _xform(&ctx.inner, Ublock); \ _xtract(&ctx.inner, Ublock); \ /* Complete outer hash with inner output */ \ _xcpy(&ctx.outer, &startctx->outer); \ _xform(&ctx.outer, Ublock); \ _xtract(&ctx.outer, Ublock); \ _xxor(&result, &ctx.outer); \ } \ \ /* Reform result into output buffer. */ \ _xtract(&result, out); \ } \ \ static inline void PBKDF2(_name)(const uint8_t *pw, size_t npw, \ const uint8_t *salt, size_t nsalt, \ uint32_t iterations, \ uint8_t *out, size_t nout) \ { \ assert(iterations); \ assert(out && nout); \ \ /* Starting point for inner loop. */ \ HMAC_CTX(_name) ctx; \ HMAC_INIT(_name)(&ctx, pw, npw); \ \ /* How many blocks do we need? */ \ uint32_t blocks_needed = (uint32_t)(nout + _hashsz - 1) / _hashsz; \ \ OPENMP_PARALLEL_FOR \ for (uint32_t counter = 1; counter <= blocks_needed; counter++) \ { \ uint8_t block[_hashsz]; \ PBKDF2_F(_name)(&ctx, counter, salt, nsalt, iterations, block); \ \ size_t offset = (counter - 1) * _hashsz; \ size_t taken = MIN(nout - offset, _hashsz); \ memcpy(out + offset, block, taken); \ } \ } static inline void sha256_extract(SHA256_CTX *restrict ctx, uint8_t *restrict out) { write32_be(ctx->state[0], out); write32_be(ctx->state[1], out + 4); write32_be(ctx->state[2], out + 8); write32_be(ctx->state[3], out + 12); write32_be(ctx->state[4], out + 16); write32_be(ctx->state[5], out + 20); write32_be(ctx->state[6], out + 24); write32_be(ctx->state[7], out + 28); } static inline void sha256_cpy(SHA256_CTX *restrict out, const SHA256_CTX *restrict in) { out->state[0] = in->state[0]; out->state[1] = in->state[1]; out->state[2] = in->state[2]; out->state[3] = in->state[3]; out->state[4] = in->state[4]; out->state[5] = in->state[5]; out->state[6] = in->state[6]; out->state[7] = in->state[7]; } static inline void sha256_xor(SHA256_CTX *restrict out, const SHA256_CTX *restrict in) { out->state[0] ^= in->state[0]; out->state[1] ^= in->state[1]; out->state[2] ^= in->state[2]; out->state[3] ^= in->state[3]; out->state[4] ^= in->state[4]; out->state[5] ^= in->state[5]; out->state[6] ^= in->state[6]; out->state[7] ^= in->state[7]; } DECL_PBKDF2(sha256, 64, 32, SHA256_CTX, _librist_SHA256_Init, _librist_SHA256_Update, _librist_SHA256_Transform, _librist_SHA256_Final, sha256_cpy, sha256_extract, sha256_xor) void fastpbkdf2_hmac_sha256(const uint8_t *pw, size_t npw, const uint8_t *salt, size_t nsalt, uint32_t iterations, uint8_t *out, size_t nout) { PBKDF2(sha256)(pw, npw, salt, nsalt, iterations, out, nout); }