diff options
| author | Ulf Möller <ulf@openssl.org> | 2001-02-07 22:24:35 +0000 |
|---|---|---|
| committer | Ulf Möller <ulf@openssl.org> | 2001-02-07 22:24:35 +0000 |
| commit | 57e7d3ce1546fc6026ffe3f1f243c54d0bb59d3e (patch) | |
| tree | 0145db13ba92d21247ffa1de25a4202603515f91 /crypto | |
| parent | a8ebe4697e99ac642fa73b20f5698091b7976f63 (diff) | |
Bleichenbacher's DSA attack
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/bn/bn.h | 1 | ||||
| -rw-r--r-- | crypto/bn/bn_rand.c | 11 | ||||
| -rw-r--r-- | crypto/dsa/dsa_ossl.c | 8 |
3 files changed, 13 insertions, 7 deletions
diff --git a/crypto/bn/bn.h b/crypto/bn/bn.h index 47e355ea9d..be4e7ae2ba 100644 --- a/crypto/bn/bn.h +++ b/crypto/bn/bn.h @@ -329,6 +329,7 @@ BIGNUM *BN_CTX_get(BN_CTX *ctx); void BN_CTX_end(BN_CTX *ctx); int BN_rand(BIGNUM *rnd, int bits, int top,int bottom); int BN_pseudo_rand(BIGNUM *rnd, int bits, int top,int bottom); +int BN_rand_range(BIGNUM *rnd, BIGNUM *min, BIGNUM *max); int BN_num_bits(const BIGNUM *a); int BN_num_bits_word(BN_ULONG); BIGNUM *BN_new(void); diff --git a/crypto/bn/bn_rand.c b/crypto/bn/bn_rand.c index bab4510345..f2c79b5e31 100644 --- a/crypto/bn/bn_rand.c +++ b/crypto/bn/bn_rand.c @@ -168,3 +168,14 @@ int BN_bntest_rand(BIGNUM *rnd, int bits, int top, int bottom) return bnrand(2, rnd, bits, top, bottom); } #endif + +/* random number r: min <= r < max */ +int BN_rand_range(BIGNUM *r, BIGNUM *min, BIGNUM *max) + { + int n = BN_num_bits(max); + do + { + if (!BN_rand(r, n, 0, 0)) return 0; + } while ((min && BN_cmp(r, min) < 0) || BN_cmp(r, max) >= 0); + return 1; + } diff --git a/crypto/dsa/dsa_ossl.c b/crypto/dsa/dsa_ossl.c index 4b600fa731..7304037947 100644 --- a/crypto/dsa/dsa_ossl.c +++ b/crypto/dsa/dsa_ossl.c @@ -180,13 +180,7 @@ static int dsa_sign_setup(DSA *dsa, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM **rp) kinv=NULL; /* Get random k */ - for (;;) - { - if (!BN_rand(&k, BN_num_bits(dsa->q), 0, 0)) goto err; - if (BN_cmp(&k,dsa->q) >= 0) - BN_sub(&k,&k,dsa->q); - if (!BN_is_zero(&k)) break; - } + if (!BN_rand_range(&k, BN_value_one(), dsa->q)) goto err; if ((dsa->method_mont_p == NULL) && (dsa->flags & DSA_FLAG_CACHE_MONT_P)) { |