1 files changed, 24 insertions, 33 deletions

diff --git a/schnorr.c b/schnorr.c
index 93822fed4..aa3a57770 100644
--- a/schnorr.c
+++ b/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 $ */
 /*
  * Copyright (c) 2008 Damien Miller.  All rights reserved.
  *
@@ -41,6 +41,7 @@
 #include "log.h"
 
 #include "schnorr.h"
+#include "digest.h"
 
 #include "openbsd-compat/openssl-compat.h"
 
@@ -57,12 +58,12 @@
 
 /*
  * 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;
@@ -88,7 +89,7 @@ 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;
@@ -113,7 +114,7 @@ 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.
  * 
@@ -123,7 +124,7 @@ 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;
@@ -173,7 +174,7 @@ 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;
@@ -223,7 +224,7 @@ 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;
 
@@ -248,13 +249,13 @@ 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;
@@ -302,7 +303,7 @@ 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;
@@ -385,7 +386,7 @@ 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);
@@ -443,43 +444,33 @@ 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 */