diff options
| author |   jsing <jsing@openbsd.org> | 2018-06-14 17:15:41 +0000 |
|---|---|---|
| committer | jsing <jsing@openbsd.org> | 2018-06-14 17:15:41 +0000 |
| commit | 2a4f1d4f204a8f70216dd79e5f3747e32998ea7b (patch) | |
| tree | bc406f5c088951808f358e330f1f0d6ee556ca99 /lib/libcrypto/dsa/dsa_ossl.c | |
| parent | Fix a potential leak/incorrect return value in DSA signature generation. (diff) | |
| download | wireguard-openbsd-2a4f1d4f204a8f70216dd79e5f3747e32998ea7b.tar.xz wireguard-openbsd-2a4f1d4f204a8f70216dd79e5f3747e32998ea7b.zip | |
Pull up the code that converts the digest to a BIGNUM - this only needs
to occur once and not be repeated if the signature generation has to be
repeated.
ok tb@
Diffstat (limited to 'lib/libcrypto/dsa/dsa_ossl.c')
| -rw-r--r-- | lib/libcrypto/dsa/dsa_ossl.c | 20 |
1 files changed, 10 insertions, 10 deletions
diff --git a/lib/libcrypto/dsa/dsa_ossl.c b/lib/libcrypto/dsa/dsa_ossl.c index d864875266e..9545cff5f8e 100644 --- a/lib/libcrypto/dsa/dsa_ossl.c +++ b/lib/libcrypto/dsa/dsa_ossl.c @@ -1,4 +1,4 @@ -/* $OpenBSD: dsa_ossl.c,v 1.34 2018/06/14 17:14:12 jsing Exp $ */ +/* $OpenBSD: dsa_ossl.c,v 1.35 2018/06/14 17:15:41 jsing Exp $ */ /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) * All rights reserved. * @@ -117,6 +117,15 @@ dsa_do_sign(const unsigned char *dgst, int dlen, DSA *dsa) if (ctx == NULL) goto err; + /* + * If the digest length is greater than the size of q use the + * BN_num_bits(dsa->q) leftmost bits of the digest, see FIPS 186-3, 4.2. + */ + if (dlen > BN_num_bytes(dsa->q)) + dlen = BN_num_bytes(dsa->q); + if (BN_bin2bn(dgst, dlen, &m) == NULL) + goto err; + redo: if (dsa->kinv == NULL || dsa->r == NULL) { if (!DSA_sign_setup(dsa, ctx, &kinv, &r)) @@ -129,15 +138,6 @@ dsa_do_sign(const unsigned char *dgst, int dlen, DSA *dsa) noredo = 1; } - /* - * If the digest length is greater than the size of q use the - * BN_num_bits(dsa->q) leftmost bits of the digest, see FIPS 186-3, 4.2. - */ - if (dlen > BN_num_bytes(dsa->q)) - dlen = BN_num_bytes(dsa->q); - if (BN_bin2bn(dgst,dlen,&m) == NULL) - goto err; - /* Compute s = inv(k) (m + xr) mod q */ if (!BN_mod_mul(&xr, dsa->priv_key, r, dsa->q, ctx)) /* s = xr */ goto err; |