diff options
author | nagendra modadugu <ngm@google.com> | 2016-02-04 18:03:01 -0800 |
---|---|---|
committer | chrome-bot <chrome-bot@chromium.org> | 2016-02-08 13:47:49 -0800 |
commit | e68019e3492a62980d5303cecb9cc29cf96cc170 (patch) | |
tree | abb6d3f966f7070d37438e031b3a82358ec88b9d /chip | |
parent | cb663d93a27702f247fc798e4d0a7068c82dcd0f (diff) | |
download | chrome-ec-e68019e3492a62980d5303cecb9cc29cf96cc170.tar.gz |
CR50: enable the bignum library to handle word un-aligned keys
The TPM2 api does not require keys to be word-aligned,
so have the compiler generate alignment-safe reads where
necessary.
BRANCH=none
BUG=chrome-os-partner:43025,chrome-os-partner:47524
TEST=tests under test/tpm2/ pass, more TCG tests pass.
Change-Id: I247e29f2bec139ab7ed4010ffb58cdae77ba9e0b
Signed-off-by: nagendra modadugu <ngm@google.com>
Reviewed-on: https://chromium-review.googlesource.com/326201
Commit-Ready: Nagendra Modadugu <ngm@google.com>
Tested-by: Nagendra Modadugu <ngm@google.com>
Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>
Diffstat (limited to 'chip')
-rw-r--r-- | chip/g/dcrypto/bn.c | 51 | ||||
-rw-r--r-- | chip/g/dcrypto/internal.h | 6 | ||||
-rw-r--r-- | chip/g/dcrypto/rsa.c | 4 |
3 files changed, 31 insertions, 30 deletions
diff --git a/chip/g/dcrypto/bn.c b/chip/g/dcrypto/bn.c index 829d10e602..f4aaf11912 100644 --- a/chip/g/dcrypto/bn.c +++ b/chip/g/dcrypto/bn.c @@ -18,16 +18,14 @@ void bn_init(struct BIGNUM *b, void *buf, size_t len) { /* Only word-multiple sized buffers accepted. */ assert((len & 0x3) == 0); - /* Only word-aligned buffers accepted. */ - assert(((uintptr_t) buf & 0x3) == 0); b->dmax = len / BN_BYTES; dcrypto_memset(buf, 0x00, len); - b->d = (uint32_t *) buf; + b->d = (struct access_helper *) buf; } int bn_check_topbit(const struct BIGNUM *N) { - return N->d[N->dmax - 1] >> 31; + return BN_DIGIT(N, N->dmax - 1) >> 31; } /* a[n]. */ @@ -43,7 +41,7 @@ static int bn_is_bit_set(const struct BIGNUM *a, int n) if (a->dmax <= i) return 0; - return (a->d[i] >> j) & 1; + return (BN_DIGIT(a, i) >> j) & 1; } /* a[] >= b[]. */ @@ -52,9 +50,9 @@ static int bn_gte(const struct BIGNUM *a, const struct BIGNUM *b) { int i; - for (i = a->dmax - 1; a->d[i] == b->d[i] && i > 0; --i) + for (i = a->dmax - 1; BN_DIGIT(a, i) == BN_DIGIT(b, i) && i > 0; --i) ; - return a->d[i] >= b->d[i]; + return BN_DIGIT(a, i) >= BN_DIGIT(b, i); } /* c[] = c[] - a[], assumes c > a. */ @@ -64,8 +62,8 @@ static uint32_t bn_sub(struct BIGNUM *c, const struct BIGNUM *a) int i; for (i = 0; i < a->dmax; i++) { - A += (uint64_t) c->d[i] - a->d[i]; - c->d[i] = (uint32_t) A; + A += (uint64_t) BN_DIGIT(c, i) - BN_DIGIT(a, i); + BN_DIGIT(c, i) = (uint32_t) A; A >>= 32; } return (uint32_t) A; /* 0 or -1. */ @@ -78,8 +76,8 @@ static uint32_t bn_add(struct BIGNUM *c, const struct BIGNUM *a) int i; for (i = 0; i < a->dmax; ++i) { - A += (uint64_t) c->d[i] + a->d[i]; - c->d[i] = (uint32_t) A; + A += (uint64_t) BN_DIGIT(c, i) + BN_DIGIT(a, i); + BN_DIGIT(c, i) = (uint32_t) A; A >>= 32; } @@ -94,9 +92,9 @@ static uint32_t bn_lshift(struct BIGNUM *r) uint32_t carry = 0; for (i = 0; i < r->dmax; i++) { - w = (r->d[i] << 1) | carry; - carry = r->d[i] >> 31; - r->d[i] = w; + w = (BN_DIGIT(r, i) << 1) | carry; + carry = BN_DIGIT(r, i) >> 31; + BN_DIGIT(r, i) = w; } return carry; } @@ -113,20 +111,21 @@ static void bn_mont_mul_add(struct BIGNUM *c, const uint32_t a, { register uint64_t tmp; - tmp = c->d[0] + (uint64_t) a * b->d[0]; + tmp = BN_DIGIT(c, 0) + (uint64_t) a * BN_DIGIT(b, 0); A = tmp >> 32; d0 = (uint32_t) tmp * (uint32_t) nprime; - tmp = (uint32_t)tmp + (uint64_t) d0 * N->d[0]; + tmp = (uint32_t)tmp + (uint64_t) d0 * BN_DIGIT(N, 0); B = tmp >> 32; } for (i = 0; i < N->dmax - 1;) { register uint64_t tmp; - tmp = A + (uint64_t) a * b->d[i + 1] + c->d[i + 1]; + tmp = A + (uint64_t) a * BN_DIGIT(b, i + 1) + + BN_DIGIT(c, i + 1); A = tmp >> 32; - tmp = B + (uint64_t) d0 * N->d[i + 1] + (uint32_t) tmp; - c->d[i] = (uint32_t) tmp; + tmp = B + (uint64_t) d0 * BN_DIGIT(N, i + 1) + (uint32_t) tmp; + BN_DIGIT(c, i) = (uint32_t) tmp; B = tmp >> 32; ++i; } @@ -134,7 +133,7 @@ static void bn_mont_mul_add(struct BIGNUM *c, const uint32_t a, { uint64_t tmp = (uint64_t) A + B; - c->d[i] = (uint32_t) tmp; + BN_DIGIT(c, i) = (uint32_t) tmp; A = tmp >> 32; /* 0 or 1. */ if (A) bn_sub(c, N); @@ -149,11 +148,11 @@ static void bn_mont_mul(struct BIGNUM *c, const struct BIGNUM *a, int i; for (i = 0; i < N->dmax; i++) - c->d[i] = 0; + BN_DIGIT(c, i) = 0; - bn_mont_mul_add(c, a ? a->d[0] : 1, b, nprime, N); + bn_mont_mul_add(c, a ? BN_DIGIT(a, 0) : 1, b, nprime, N); for (i = 1; i < N->dmax; i++) - bn_mont_mul_add(c, a ? a->d[i] : 0, b, nprime, N); + bn_mont_mul_add(c, a ? BN_DIGIT(a, i) : 0, b, nprime, N); } /* Mongomery R * R % N, R = 1 << (1 + log2N). */ @@ -206,11 +205,11 @@ void bn_mont_modexp(struct BIGNUM *output, const struct BIGNUM *input, bn_init(&acc, acc_buf, bn_size(N)); bn_init(&aR, aR_buf, bn_size(N)); - nprime = bn_compute_nprime(N->d[0]); + nprime = bn_compute_nprime(BN_DIGIT(N, 0)); bn_compute_RR(&RR, N); bn_mont_mul(&acc, NULL, &RR, nprime, N); /* R = 1 * RR / R % N */ bn_mont_mul(&aR, input, &RR, nprime, N); /* aR = a * RR / R % N */ - output->d[0] = 1; + BN_DIGIT(output, 0) = 1; /* TODO(ngm): burn stack space and use windowing. */ for (i = exp->dmax * BN_BITS2 - 1; i >= 0; i--) { @@ -232,7 +231,7 @@ void bn_mont_modexp(struct BIGNUM *output, const struct BIGNUM *input, bn_mont_mul(output, NULL, &acc, nprime, N); /* Convert out. */ /* Copy to output buffer if necessary. */ - if (acc.d != acc_buf) { + if (acc.d != (struct access_helper *) acc_buf) { memcpy(acc.d, acc_buf, bn_size(output)); *output = acc; } diff --git a/chip/g/dcrypto/internal.h b/chip/g/dcrypto/internal.h index 61db833a53..36aa35f6bf 100644 --- a/chip/g/dcrypto/internal.h +++ b/chip/g/dcrypto/internal.h @@ -89,10 +89,12 @@ void dcrypto_sha_wait(enum sha_mode mode, uint32_t *digest); #define BN_BYTES 4 struct BIGNUM { - uint32_t dmax; /* Size of d, in 32-bit words. */ - uint32_t *d; /* Word array, little endian format ... */ + uint32_t dmax; /* Size of d, in 32-bit words. */ + struct access_helper *d; /* Word array, little endian format ... */ }; +#define BN_DIGIT(b, i) ((b)->d[(i)].udata) + void bn_init(struct BIGNUM *bn, void *buf, size_t len); #define bn_size(b) ((b)->dmax * BN_BYTES) int bn_check_topbit(const struct BIGNUM *N); diff --git a/chip/g/dcrypto/rsa.c b/chip/g/dcrypto/rsa.c index d9774a2101..b6128923ef 100644 --- a/chip/g/dcrypto/rsa.c +++ b/chip/g/dcrypto/rsa.c @@ -339,7 +339,7 @@ int DCRYPTO_rsa_encrypt(struct RSA *rsa, uint8_t *out, uint32_t *out_len, bn_init(&padded, padded_buf, bn_size(&rsa->N)); bn_init(&encrypted, out, bn_size(&rsa->N)); bn_init(&e, e_buf, sizeof(e_buf)); - *e.d = rsa->e; + BN_DIGIT(&e, 0) = rsa->e; switch (padding) { case PADDING_MODE_OAEP: @@ -479,7 +479,7 @@ int DCRYPTO_rsa_verify(struct RSA *rsa, const uint8_t *digest, memcpy(signature_buf, sig, bn_size(&rsa->N)); bn_init(&padded, padded_buf, bn_size(&rsa->N)); bn_init(&e, e_buf, sizeof(e_buf)); - *e.d = rsa->e; + BN_DIGIT(&e, 0) = rsa->e; /* Reverse from big-endian to little-endian notation. */ reverse((uint8_t *) signature.d, signature.dmax * BN_BYTES); |