diff options
Diffstat (limited to 'common/rsa.c')
| -rw-r--r-- | common/rsa.c | 56 |
1 files changed, 24 insertions, 32 deletions
diff --git a/common/rsa.c b/common/rsa.c index 10f0afa4b4..4df6fc136a 100644 --- a/common/rsa.c +++ b/common/rsa.c @@ -1,4 +1,4 @@ -/* Copyright 2014 The Chromium OS Authors. All rights reserved. +/* Copyright 2014 The ChromiumOS Authors * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. */ @@ -39,16 +39,14 @@ static int ge_mod(const struct rsa_public_key *key, const uint32_t *a) if (a[i] > key->n[i]) return 1; } - return 1; /* equal */ + return 1; /* equal */ } /** * Montgomery c[] += a * b[] / R % mod */ -static void mont_mul_add(const struct rsa_public_key *key, - uint32_t *c, - const uint32_t a, - const uint32_t *b) +static void mont_mul_add(const struct rsa_public_key *key, uint32_t *c, + const uint32_t a, const uint32_t *b) { uint64_t A = mula32(a, b[0], c[0]); uint32_t d0 = (uint32_t)A * key->n0inv; @@ -73,9 +71,8 @@ static void mont_mul_add(const struct rsa_public_key *key, /** * Montgomery c[] += 0 * b[] / R % mod */ -static void mont_mul_add_0(const struct rsa_public_key *key, - uint32_t *c, - const uint32_t *b) +static void mont_mul_add_0(const struct rsa_public_key *key, uint32_t *c, + const uint32_t *b) { uint32_t d0 = c[0] * key->n0inv; uint64_t B = mula32(d0, key->n[0], c[0]); @@ -90,8 +87,7 @@ static void mont_mul_add_0(const struct rsa_public_key *key, } /* Montgomery c[] = a[] * 1 / R % key. */ -static void mont_mul_1(const struct rsa_public_key *key, - uint32_t *c, +static void mont_mul_1(const struct rsa_public_key *key, uint32_t *c, const uint32_t *a) { int i; @@ -108,10 +104,8 @@ static void mont_mul_1(const struct rsa_public_key *key, /** * Montgomery c[] = a[] * b[] / R % mod */ -static void mont_mul(const struct rsa_public_key *key, - uint32_t *c, - const uint32_t *a, - const uint32_t *b) +static void mont_mul(const struct rsa_public_key *key, uint32_t *c, + const uint32_t *a, const uint32_t *b) { uint32_t i; for (i = 0; i < RSANUMWORDS; ++i) @@ -136,21 +130,20 @@ static void mod_pow(const struct rsa_public_key *key, uint8_t *inout, uint32_t *a = workbuf32; uint32_t *a_r = a + RSANUMWORDS; uint32_t *aa_r = a_r + RSANUMWORDS; - uint32_t *aaa = aa_r; /* Re-use location. */ + uint32_t *aaa = aa_r; /* Re-use location. */ int i; /* Convert from big endian byte array to little endian word array. */ for (i = 0; i < RSANUMWORDS; ++i) { - uint32_t tmp = - (inout[((RSANUMWORDS - 1 - i) * 4) + 0] << 24) | - (inout[((RSANUMWORDS - 1 - i) * 4) + 1] << 16) | - (inout[((RSANUMWORDS - 1 - i) * 4) + 2] << 8) | - (inout[((RSANUMWORDS - 1 - i) * 4) + 3] << 0); + uint32_t tmp = (inout[((RSANUMWORDS - 1 - i) * 4) + 0] << 24) | + (inout[((RSANUMWORDS - 1 - i) * 4) + 1] << 16) | + (inout[((RSANUMWORDS - 1 - i) * 4) + 2] << 8) | + (inout[((RSANUMWORDS - 1 - i) * 4) + 3] << 0); a[i] = tmp; } /* TODO(drinkcat): This operation could be precomputed to save time. */ - mont_mul(key, a_r, a, key->rr); /* a_r = a * RR / R mod M */ + mont_mul(key, a_r, a, key->rr); /* a_r = a * RR / R mod M */ #ifdef CONFIG_RSA_EXPONENT_3 mont_mul(key, aa_r, a_r, a_r); mont_mul(key, a, aa_r, a_r); @@ -159,9 +152,10 @@ static void mod_pow(const struct rsa_public_key *key, uint8_t *inout, /* Exponent 65537 */ for (i = 0; i < 16; i += 2) { mont_mul(key, aa_r, a_r, a_r); /* aa_r = a_r * a_r / R mod M */ - mont_mul(key, a_r, aa_r, aa_r);/* a_r = aa_r * aa_r / R mod M */ + mont_mul(key, a_r, aa_r, aa_r); /* a_r = aa_r * aa_r / R mod M + */ } - mont_mul(key, aaa, a_r, a); /* aaa = a_r * a / R mod M */ + mont_mul(key, aaa, a_r, a); /* aaa = a_r * a / R mod M */ #endif /* Make sure aaa < mod; aaa is at most 1x mod too large. */ @@ -173,8 +167,8 @@ static void mod_pow(const struct rsa_public_key *key, uint8_t *inout, uint32_t tmp = aaa[i]; *inout++ = (uint8_t)(tmp >> 24); *inout++ = (uint8_t)(tmp >> 16); - *inout++ = (uint8_t)(tmp >> 8); - *inout++ = (uint8_t)(tmp >> 0); + *inout++ = (uint8_t)(tmp >> 8); + *inout++ = (uint8_t)(tmp >> 0); } } @@ -192,11 +186,9 @@ static void mod_pow(const struct rsa_public_key *key, uint8_t *inout, * * PS: octet string consisting of {Length(RSA Key) - Length(T) - 3} 0xFF */ -static const uint8_t sha256_tail[] = { - 0x00, 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, - 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, - 0x05, 0x00, 0x04, 0x20 -}; +static const uint8_t sha256_tail[] = { 0x00, 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, + 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, + 0x02, 0x01, 0x05, 0x00, 0x04, 0x20 }; #define PKCS_PAD_SIZE (RSANUMBYTES - SHA256_DIGEST_SIZE) @@ -255,5 +247,5 @@ int rsa_verify(const struct rsa_public_key *key, const uint8_t *signature, if (memcmp(buf + PKCS_PAD_SIZE, sha, SHA256_DIGEST_SIZE) != 0) return 0; - return 1; /* All checked out OK. */ + return 1; /* All checked out OK. */ } |