RSA signature verification and SHA-1/256/512 reference implementation for verified boot.

src/platform/vboot_reference/crypto/sha1.c

+/* Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/* SHA-1 implementation largely based on libmincrypt in the the Android
+ * Open Source Project (platorm/system/core.git/libmincrypt/sha.c
+ */
+
+#include "sha.h"
+
+/* Some machines lack byteswap.h and endian.h. These have to use the
+ * slower code, even if they're little-endian.
+ */
+
+#if defined(HAVE_ENDIAN_H) && defined(HAVE_LITTLE_ENDIAN)
+
+#include <byteswap.h>
+#include <memory.h>
+
+/* This version is about 28% faster than the generic version below,
+ * but assumes little-endianness.
+ */
+static inline uint32_t ror27(uint32_t val) {
+  return (val >> 27) | (val << 5);
+}
+static inline uint32_t ror2(uint32_t val) {
+  return (val >> 2) | (val << 30);
+}
+static inline uint32_t ror31(uint32_t val) {
+  return (val >> 31) | (val << 1);
+}
+
+static void SHA1_Transform(SHA_CTX* ctx) {
+  uint32_t W[80];
+  register uint32_t A, B, C, D, E;
+  int t;
+
+  A = ctx->state[0];
+  B = ctx->state[1];
+  C = ctx->state[2];
+  D = ctx->state[3];
+  E = ctx->state[4];
+
+#define SHA_F1(A,B,C,D,E,t)                     \
+  E += ror27(A) +                               \
+      (W[t] = bswap_32(ctx->buf.w[t])) +        \
+      (D^(B&(C^D))) + 0x5A827999;               \
+  B = ror2(B);
+
+  for (t = 0; t < 15; t += 5) {
+    SHA_F1(A,B,C,D,E,t + 0);
+    SHA_F1(E,A,B,C,D,t + 1);
+    SHA_F1(D,E,A,B,C,t + 2);
+    SHA_F1(C,D,E,A,B,t + 3);
+    SHA_F1(B,C,D,E,A,t + 4);
+  }
+  SHA_F1(A,B,C,D,E,t + 0);  /* 16th one, t == 15 */
+
+#undef SHA_F1
+
+#define SHA_F1(A,B,C,D,E,t)                                     \
+  E += ror27(A) +                                               \
+      (W[t] = ror31(W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16])) +     \
+      (D^(B&(C^D))) + 0x5A827999;                               \
+  B = ror2(B);
+
+  SHA_F1(E,A,B,C,D,t + 1);
+  SHA_F1(D,E,A,B,C,t + 2);
+  SHA_F1(C,D,E,A,B,t + 3);
+  SHA_F1(B,C,D,E,A,t + 4);
+
+#undef SHA_F1
+
+#define SHA_F2(A,B,C,D,E,t)                                     \
+  E += ror27(A) +                                               \
+      (W[t] = ror31(W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16])) +     \
+      (B^C^D) + 0x6ED9EBA1;                                     \
+  B = ror2(B);
+
+  for (t = 20; t < 40; t += 5) {
+    SHA_F2(A,B,C,D,E,t + 0);
+    SHA_F2(E,A,B,C,D,t + 1);
+    SHA_F2(D,E,A,B,C,t + 2);
+    SHA_F2(C,D,E,A,B,t + 3);
+    SHA_F2(B,C,D,E,A,t + 4);
+  }
+
+#undef SHA_F2
+
+#define SHA_F3(A,B,C,D,E,t)                                     \
+  E += ror27(A) +                                               \
+      (W[t] = ror31(W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16])) +     \
+      ((B&C)|(D&(B|C))) + 0x8F1BBCDC;                           \
+  B = ror2(B);
+
+  for (; t < 60; t += 5) {
+    SHA_F3(A,B,C,D,E,t + 0);
+    SHA_F3(E,A,B,C,D,t + 1);
+    SHA_F3(D,E,A,B,C,t + 2);
+    SHA_F3(C,D,E,A,B,t + 3);
+    SHA_F3(B,C,D,E,A,t + 4);
+  }
+
+#undef SHA_F3
+
+#define SHA_F4(A,B,C,D,E,t)                                     \
+  E += ror27(A) +                                               \
+      (W[t] = ror31(W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16])) +     \
+      (B^C^D) + 0xCA62C1D6;                                     \
+  B = ror2(B);
+
+  for (; t < 80; t += 5) {
+    SHA_F4(A,B,C,D,E,t + 0);
+    SHA_F4(E,A,B,C,D,t + 1);
+    SHA_F4(D,E,A,B,C,t + 2);
+    SHA_F4(C,D,E,A,B,t + 3);
+    SHA_F4(B,C,D,E,A,t + 4);
+  }
+
+#undef SHA_F4
+
+  ctx->state[0] += A;
+  ctx->state[1] += B;
+  ctx->state[2] += C;
+  ctx->state[3] += D;
+  ctx->state[4] += E;
+}
+
+void SHA1_update(SHA1_CTX* ctx, const uint8_t* data, size_t len) {
+  int i = ctx->count % sizeof(ctx->buf);
+  const uint8_t* p = (const uint8_t*)data;
+
+  ctx->count += len;
+
+  while (len > sizeof(ctx->buf) - i) {
+    memcpy(&ctx->buf.b[i], p, sizeof(ctx->buf) - i);
+    len -= sizeof(ctx->buf) - i;
+    p += sizeof(ctx->buf) - i;
+    SHA1_Transform(ctx);
+    i = 0;
+  }
+
+  while (len--) {
+    ctx->buf.b[i++] = *p++;
+    if (i == sizeof(ctx->buf)) {
+      SHA1_Transform(ctx);
+      i = 0;
+    }
+  }
+}
+
+
+uint8_t* SHA1_final(SHA_CTX* ctx) {
+  uint64_t cnt = ctx->count * 8;
+  int i;
+
+  SHA1_update(ctx, (uint8_t*)"\x80", 1);
+  while ((ctx->count % sizeof(ctx->buf)) != (sizeof(ctx->buf) - 8)) {
+    SHA1_update(ctx, (uint8_t*)"\0", 1);
+  }
+  for (i = 0; i < 8; ++i) {
+    uint8_t tmp = cnt >> ((7 - i) * 8);
+    SHA1_update(ctx, &tmp, 1);
+  }
+
+  for (i = 0; i < 5; i++) {
+    ctx->buf.w[i] = bswap_32(ctx->state[i]);
+  }
+
+  return ctx->buf.b;
+}
+
+#else   /* #if defined(HAVE_ENDIAN_H) && defined(HAVE_LITTLE_ENDIAN) */
+
+#define rol(bits, value) (((value) << (bits)) | ((value) >> (32 - (bits))))
+
+static void SHA1_transform(SHA1_CTX *ctx) {
+  uint32_t W[80];
+  uint32_t A, B, C, D, E;
+  uint8_t *p = ctx->buf;
+  int t;
+
+  for(t = 0; t < 16; ++t) {
+    uint32_t tmp =  *p++ << 24;
+    tmp |= *p++ << 16;
+    tmp |= *p++ << 8;
+    tmp |= *p++;
+    W[t] = tmp;
+  }
+
+  for(; t < 80; t++) {
+    W[t] = rol(1,W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16]);
+  }
+
+  A = ctx->state[0];
+  B = ctx->state[1];
+  C = ctx->state[2];
+  D = ctx->state[3];
+  E = ctx->state[4];
+
+  for(t = 0; t < 80; t++) {
+    uint32_t tmp = rol(5,A) + E + W[t];
+
+    if (t < 20)
+      tmp += (D^(B&(C^D))) + 0x5A827999;
+    else if ( t < 40)
+      tmp += (B^C^D) + 0x6ED9EBA1;
+    else if ( t < 60)
+      tmp += ((B&C)|(D&(B|C))) + 0x8F1BBCDC;
+    else
+      tmp += (B^C^D) + 0xCA62C1D6;
+
+    E = D;
+    D = C;
+    C = rol(30,B);
+    B = A;
+    A = tmp;
+  }
+
+  ctx->state[0] += A;
+  ctx->state[1] += B;
+  ctx->state[2] += C;
+  ctx->state[3] += D;
+  ctx->state[4] += E;
+}
+
+void SHA1_update(SHA1_CTX *ctx, const uint8_t *data, int len) {
+  int i = ctx->count % sizeof(ctx->buf);
+  const uint8_t* p = (const uint8_t*) data;
+
+  ctx->count += len;
+
+  while (len--) {
+    ctx->buf[i++] = *p++;
+    if (i == sizeof(ctx->buf)) {
+      SHA1_transform(ctx);
+      i = 0;
+    }
+  }
+}
+uint8_t* SHA1_final(SHA1_CTX *ctx) {
+  uint8_t *p = ctx->buf;
+  uint64_t cnt = ctx->count * 8;
+  int i;
+
+  SHA1_update(ctx, (uint8_t*)"\x80", 1);
+  while ((ctx->count % sizeof(ctx->buf)) != (sizeof(ctx->buf) - 8)) {
+    SHA1_update(ctx, (uint8_t*)"\0", 1);
+  }
+  for (i = 0; i < 8; ++i) {
+    uint8_t tmp = cnt >> ((7 - i) * 8);
+    SHA1_update(ctx, &tmp, 1);
+  }
+
+  for (i = 0; i < 5; i++) {
+    uint32_t tmp = ctx->state[i];
+    *p++ = tmp >> 24;
+    *p++ = tmp >> 16;
+    *p++ = tmp >> 8;
+    *p++ = tmp >> 0;
+  }
+
+  return ctx->buf;
+}
+
+#endif /* endianness */
+
+void SHA1_init(SHA1_CTX* ctx) {
+  ctx->state[0] = 0x67452301;
+  ctx->state[1] = 0xEFCDAB89;
+  ctx->state[2] = 0x98BADCFE;
+  ctx->state[3] = 0x10325476;
+  ctx->state[4] = 0xC3D2E1F0;
+  ctx->count = 0;
+}
+
+uint8_t* SHA1(const void *data, int len, uint8_t *digest) {
+  const uint8_t *p;
+  int i;
+  SHA1_CTX ctx;
+  SHA1_init(&ctx);
+  SHA1_update(&ctx, data, len);
+  p = SHA1_final(&ctx);
+  for (i = 0; i < SHA1_DIGEST_SIZE; ++i) {
+    digest[i] = *p++;
+  }
+  return digest;
+}