diff options
Diffstat (limited to 'crypto/openssh/schnorr.c')
| -rw-r--r-- | crypto/openssh/schnorr.c | 57 |
1 files changed, 24 insertions, 33 deletions
diff --git a/crypto/openssh/schnorr.c b/crypto/openssh/schnorr.c index c14ec94..7714182 100644 --- a/crypto/openssh/schnorr.c +++ b/crypto/openssh/schnorr.c @@ -1,4 +1,4 @@ -/* $OpenBSD: schnorr.c,v 1.8 2013/11/08 00:39:15 djm Exp $ */ +/* $OpenBSD: schnorr.c,v 1.9 2014/01/09 23:20:00 djm Exp $ */ /* $FreeBSD$ */ /* * Copyright (c) 2008 Damien Miller. All rights reserved. @@ -42,6 +42,7 @@ #include "log.h" #include "schnorr.h" +#include "digest.h" #ifdef JPAKE @@ -60,12 +61,12 @@ /* * Calculate hash component of Schnorr signature H(g || g^v || g^x || id) - * using the hash function defined by "evp_md". Returns signature as + * using the hash function defined by "hash_alg". Returns signature as * bignum or NULL on error. */ static BIGNUM * schnorr_hash(const BIGNUM *p, const BIGNUM *q, const BIGNUM *g, - const EVP_MD *evp_md, const BIGNUM *g_v, const BIGNUM *g_x, + int hash_alg, const BIGNUM *g_v, const BIGNUM *g_x, const u_char *id, u_int idlen) { u_char *digest; @@ -91,7 +92,7 @@ schnorr_hash(const BIGNUM *p, const BIGNUM *q, const BIGNUM *g, SCHNORR_DEBUG_BUF((buffer_ptr(&b), buffer_len(&b), "%s: hashblob", __func__)); - if (hash_buffer(buffer_ptr(&b), buffer_len(&b), evp_md, + if (hash_buffer(buffer_ptr(&b), buffer_len(&b), hash_alg, &digest, &digest_len) != 0) { error("%s: hash_buffer", __func__); goto out; @@ -116,7 +117,7 @@ schnorr_hash(const BIGNUM *p, const BIGNUM *q, const BIGNUM *g, /* * Generate Schnorr signature to prove knowledge of private value 'x' used * in public exponent g^x, under group defined by 'grp_p', 'grp_q' and 'grp_g' - * using the hash function "evp_md". + * using the hash function "hash_alg". * 'idlen' bytes from 'id' will be included in the signature hash as an anti- * replay salt. * @@ -126,7 +127,7 @@ schnorr_hash(const BIGNUM *p, const BIGNUM *q, const BIGNUM *g, */ int schnorr_sign(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g, - const EVP_MD *evp_md, const BIGNUM *x, const BIGNUM *g_x, + int hash_alg, const BIGNUM *x, const BIGNUM *g_x, const u_char *id, u_int idlen, BIGNUM **r_p, BIGNUM **e_p) { int success = -1; @@ -176,7 +177,7 @@ schnorr_sign(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g, SCHNORR_DEBUG_BN((g_v, "%s: g_v = ", __func__)); /* h = H(g || g^v || g^x || id) */ - if ((h = schnorr_hash(grp_p, grp_q, grp_g, evp_md, g_v, g_x, + if ((h = schnorr_hash(grp_p, grp_q, grp_g, hash_alg, g_v, g_x, id, idlen)) == NULL) { error("%s: schnorr_hash failed", __func__); goto out; @@ -226,7 +227,7 @@ schnorr_sign_buf(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g, Buffer b; BIGNUM *r, *e; - if (schnorr_sign(grp_p, grp_q, grp_g, EVP_sha256(), + if (schnorr_sign(grp_p, grp_q, grp_g, SSH_DIGEST_SHA256, x, g_x, id, idlen, &r, &e) != 0) return -1; @@ -251,13 +252,13 @@ schnorr_sign_buf(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g, /* * Verify Schnorr signature { r (v - xh mod q), e (g^v mod p) } against * public exponent g_x (g^x) under group defined by 'grp_p', 'grp_q' and - * 'grp_g' using hash "evp_md". + * 'grp_g' using hash "hash_alg". * Signature hash will be salted with 'idlen' bytes from 'id'. * Returns -1 on failure, 0 on incorrect signature or 1 on matching signature. */ int schnorr_verify(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g, - const EVP_MD *evp_md, const BIGNUM *g_x, const u_char *id, u_int idlen, + int hash_alg, const BIGNUM *g_x, const u_char *id, u_int idlen, const BIGNUM *r, const BIGNUM *e) { int success = -1; @@ -305,7 +306,7 @@ schnorr_verify(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g, SCHNORR_DEBUG_BN((g_xh, "%s: g_xh = ", __func__)); /* h = H(g || g^v || g^x || id) */ - if ((h = schnorr_hash(grp_p, grp_q, grp_g, evp_md, e, g_x, + if ((h = schnorr_hash(grp_p, grp_q, grp_g, hash_alg, e, g_x, id, idlen)) == NULL) { error("%s: schnorr_hash failed", __func__); goto out; @@ -388,7 +389,7 @@ schnorr_verify_buf(const BIGNUM *grp_p, const BIGNUM *grp_q, goto out; } - ret = schnorr_verify(grp_p, grp_q, grp_g, EVP_sha256(), + ret = schnorr_verify(grp_p, grp_q, grp_g, SSH_DIGEST_SHA256, g_x, id, idlen, r, e); out: BN_clear_free(e); @@ -446,43 +447,33 @@ bn_rand_range_gt_one(const BIGNUM *high) return NULL; } +/* XXX convert all callers of this to use ssh_digest_memory() directly */ /* * Hash contents of buffer 'b' with hash 'md'. Returns 0 on success, * with digest via 'digestp' (caller to free) and length via 'lenp'. * Returns -1 on failure. */ int -hash_buffer(const u_char *buf, u_int len, const EVP_MD *md, +hash_buffer(const u_char *buf, u_int len, int hash_alg, u_char **digestp, u_int *lenp) { - u_char digest[EVP_MAX_MD_SIZE]; - u_int digest_len; - EVP_MD_CTX evp_md_ctx; - int success = -1; + u_char digest[SSH_DIGEST_MAX_LENGTH]; + u_int digest_len = ssh_digest_bytes(hash_alg); - EVP_MD_CTX_init(&evp_md_ctx); - - if (EVP_DigestInit_ex(&evp_md_ctx, md, NULL) != 1) { - error("%s: EVP_DigestInit_ex", __func__); - goto out; - } - if (EVP_DigestUpdate(&evp_md_ctx, buf, len) != 1) { - error("%s: EVP_DigestUpdate", __func__); - goto out; + if (digest_len == 0) { + error("%s: invalid hash", __func__); + return -1; } - if (EVP_DigestFinal_ex(&evp_md_ctx, digest, &digest_len) != 1) { - error("%s: EVP_DigestFinal_ex", __func__); - goto out; + if (ssh_digest_memory(hash_alg, buf, len, digest, digest_len) != 0) { + error("%s: digest_memory failed", __func__); + return -1; } *digestp = xmalloc(digest_len); *lenp = digest_len; memcpy(*digestp, digest, *lenp); - success = 0; - out: - EVP_MD_CTX_cleanup(&evp_md_ctx); bzero(digest, sizeof(digest)); digest_len = 0; - return success; + return 0; } /* print formatted string followed by bignum */ |
