From 8356a34d2ce9bf390030942f3fa537cc0f8aec4b Mon Sep 17 00:00:00 2001 From: Stefan Berger Date: Tue, 21 Jan 2020 15:01:44 -0500 Subject: tpm: Add sha256 implementation The following patch adds a SHA256 implementation based on the algorithm description in NIST FIPS PUB 180-4. The patch includes test cases that test the sha256 implementation and pass on big and little endian ppc64 hosts. Signed-off-by: Stefan Berger Signed-off-by: Alexey Kardashevskiy --- lib/libtpm/Makefile | 2 +- lib/libtpm/sha256.c | 214 ++++++++++++++++++++++++++++++++++++++++++++++++++++ lib/libtpm/sha256.h | 20 +++++ 3 files changed, 235 insertions(+), 1 deletion(-) create mode 100644 lib/libtpm/sha256.c create mode 100644 lib/libtpm/sha256.h (limited to 'lib') diff --git a/lib/libtpm/Makefile b/lib/libtpm/Makefile index 47fc5d0..8fa781e 100644 --- a/lib/libtpm/Makefile +++ b/lib/libtpm/Makefile @@ -23,7 +23,7 @@ TARGET = ../libtpm.a all: $(TARGET) -SRCS = tpm_drivers.c +SRCS = tpm_drivers.c sha256.c OBJS = $(SRCS:%.c=%.o) diff --git a/lib/libtpm/sha256.c b/lib/libtpm/sha256.c new file mode 100644 index 0000000..fb67e19 --- /dev/null +++ b/lib/libtpm/sha256.c @@ -0,0 +1,214 @@ +/***************************************************************************** + * Copyright (c) 2015-2020 IBM Corporation + * All rights reserved. + * This program and the accompanying materials + * are made available under the terms of the BSD License + * which accompanies this distribution, and is available at + * http://www.opensource.org/licenses/bsd-license.php + * + * Contributors: + * IBM Corporation - initial implementation + *****************************************************************************/ + +/* + * See: NIST standard for SHA-256 in FIPS PUB 180-4 + */ + +#include "byteorder.h" +#include "sha256.h" +#include "string.h" + +typedef struct _sha256_ctx { + uint32_t h[8]; +} sha256_ctx; + +static inline uint32_t rotr(uint32_t x, uint8_t n) +{ + return (x >> n) | (x << (32 - n)); +} + +static inline uint32_t Ch(uint32_t x, uint32_t y, uint32_t z) +{ + return (x & y) | ((x ^ 0xffffffff) & z); +} + +static inline uint32_t Maj(uint32_t x, uint32_t y, uint32_t z) +{ + return (x & y) | (x & z) | (y & z); +} + +static inline uint32_t sum0(uint32_t x) +{ + return rotr(x, 2) ^ rotr(x, 13) ^ rotr(x, 22); +} + +static inline uint32_t sum1(uint32_t x) +{ + return rotr(x, 6) ^ rotr(x, 11) ^ rotr(x, 25); +} + +static inline uint32_t sigma0(uint32_t x) +{ + return rotr(x, 7) ^ rotr(x, 18) ^ (x >> 3); +} + +static inline uint32_t sigma1(uint32_t x) +{ + return rotr(x, 17) ^ rotr(x, 19) ^ (x >> 10); +} + +static void sha256_block(uint32_t *w, sha256_ctx *ctx) +{ + uint32_t t; + uint32_t a, b, c, d, e, f, g, h; + uint32_t T1, T2; + + /* + * FIPS 180-4 4.2.2: SHA256 Constants + */ + static const uint32_t sha_ko[64] = { + 0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, + 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5, + 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, + 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174, + 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, + 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da, + 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, + 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967, + 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, + 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, + 0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, + 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070, + 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, + 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3, + 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, + 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2 + }; + + /* + * FIPS 180-4 6.2.2: step 1 + * + * 0 <= i <= 15: + * W(t) = M(t) + * 16 <= i <= 79: + * W(t) = sigma1(W(t-2)) + W(t-7) + sigma0(W(t-15)) + W(t-16) + */ + + /* w(0)..w(15) are in big endian format */ + for (t = 0; t <= 15; t++) + w[t] = be32_to_cpu(w[t]); + + for (t = 16; t <= 63; t++) + w[t] = sigma1(w[t-2]) + w[t-7] + sigma0(w[t-15]) + w[t-16]; + + /* + * step 2: a = H0, b = H1, c = H2, d = H3, e = H4, f = H5, g = H6, h = H7 + */ + a = ctx->h[0]; + b = ctx->h[1]; + c = ctx->h[2]; + d = ctx->h[3]; + e = ctx->h[4]; + f = ctx->h[5]; + g = ctx->h[6]; + h = ctx->h[7]; + + /* + * step 3: For i = 0 to 63: + * T1 = h + sum1(e) + Ch(e,f,g) + K(t) + W(t); + * T2 = sum0(a) + Maj(a,b,c) + * h = g; g = f; f = e; e = d + T1; d = c; c = b; b = a; a + T1 + T2 + */ + for (t = 0; t <= 63; t++) { + T1 = h + sum1(e) + Ch(e, f, g) + sha_ko[t] + w[t]; + T2 = sum0(a) + Maj(a, b, c); + h = g; + g = f; + f = e; + e = d + T1; + d = c; + c = b; + b = a; + a = T1 + T2; + } + + /* + * step 4: + * H0 = a + H0, H1 = b + H1, H2 = c + H2, H3 = d + H3, H4 = e + H4 + */ + ctx->h[0] += a; + ctx->h[1] += b; + ctx->h[2] += c; + ctx->h[3] += d; + ctx->h[4] += e; + ctx->h[5] += f; + ctx->h[6] += g; + ctx->h[7] += h; +} + +static void sha256_do(sha256_ctx *ctx, const uint8_t *data32, uint32_t length) +{ + uint32_t offset; + uint16_t num; + uint32_t bits = 0; + uint32_t w[64]; + uint64_t tmp; + + /* treat data in 64-byte chunks */ + for (offset = 0; length - offset >= 64; offset += 64) { + memcpy(w, data32 + offset, 64); + sha256_block((uint32_t *)w, ctx); + bits += (64 * 8); + } + + /* last block with less than 64 bytes */ + num = length - offset; + bits += (num << 3); + + memcpy(w, data32 + offset, num); + /* + * FIPS 180-4 5.1: Padding the Message + */ + ((uint8_t *)w)[num] = 0x80; + if (64 - (num + 1) > 0) + memset( &((uint8_t *)w)[num + 1], 0, 64 - (num + 1)); + + if (num >= 56) { + /* cannot append number of bits here */ + sha256_block((uint32_t *)w, ctx); + memset(w, 0, 60); + } + + /* write number of bits to end of block */ + tmp = cpu_to_be64(bits); + memcpy(&w[14], &tmp, 8); + + sha256_block(w, ctx); + + /* need to switch result's endianness */ + for (num = 0; num < 8; num++) + ctx->h[num] = cpu_to_be32(ctx->h[num]); +} + +void sha256(const uint8_t *data, uint32_t length, uint8_t *hash) +{ + sha256_ctx ctx = { + .h = { + /* + * FIPS 180-4: 6.2.1 + * -> 5.3.3: initial hash value + */ + 0x6a09e667, + 0xbb67ae85, + 0x3c6ef372, + 0xa54ff53a, + 0x510e527f, + 0x9b05688c, + 0x1f83d9ab, + 0x5be0cd19 + } + }; + + sha256_do(&ctx, data, length); + memcpy(hash, ctx.h, sizeof(ctx.h)); +} diff --git a/lib/libtpm/sha256.h b/lib/libtpm/sha256.h new file mode 100644 index 0000000..04b774b --- /dev/null +++ b/lib/libtpm/sha256.h @@ -0,0 +1,20 @@ +/***************************************************************************** + * Copyright (c) 2015-2020 IBM Corporation + * All rights reserved. + * This program and the accompanying materials + * are made available under the terms of the BSD License + * which accompanies this distribution, and is available at + * http://www.opensource.org/licenses/bsd-license.php + * + * Contributors: + * IBM Corporation - initial implementation + *****************************************************************************/ + +#ifndef __SHA256_H +#define __SHA256_H + +#include "types.h" + +void sha256(const uint8_t *data, uint32_t length, uint8_t *hash); + +#endif /* __SHA256_H */ -- cgit v1.1