- markus@cvs.openbsd.org 2002/01/25 21:42:11

     [ssh-dss.c ssh-rsa.c]
     use static EVP_MAX_MD_SIZE buffers for EVP_DigestFinal; ok stevesk@
     don't use evp_md->md_size, it's not public.

1 files changed, 7 insertions, 13 deletions

diff --git a/ssh-dss.c b/ssh-dss.c
index bd709a226..b81b8347d 100644
--- a/ssh-dss.c
+++ b/ssh-dss.c
@@ -23,7 +23,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: ssh-dss.c,v 1.11 2001/12/27 18:22:16 markus Exp $");
+RCSID("$OpenBSD: ssh-dss.c,v 1.12 2002/01/25 21:42:11 markus Exp $");
 
 #include <openssl/bn.h>
 #include <openssl/evp.h>
@@ -48,7 +48,7 @@ ssh_dss_sign(
         DSA_SIG *sig;
         EVP_MD *evp_md = EVP_sha1();
         EVP_MD_CTX md;
-        u_char *digest, *ret, sigblob[SIGBLOB_LEN];
+        u_char *ret, digest[EVP_MAX_MD_SIZE], sigblob[SIGBLOB_LEN];
         u_int rlen, slen, len, dlen;
         Buffer b;
 
@@ -56,16 +56,13 @@ ssh_dss_sign(
                 error("ssh_dss_sign: no DSA key");
                 return -1;
         }
-        dlen = evp_md->md_size;
-        digest = xmalloc(dlen);
         EVP_DigestInit(&md, evp_md);
         EVP_DigestUpdate(&md, data, datalen);
-        EVP_DigestFinal(&md, digest, NULL);
+        EVP_DigestFinal(&md, digest, &dlen);
 
         sig = DSA_do_sign(digest, dlen, key->dsa);
+        memset(digest, 'd', sizeof(digest));
 
-        memset(digest, 0, dlen);
-        xfree(digest);
         if (sig == NULL) {
                 error("ssh_dss_sign: sign failed");
                 return -1;
@@ -115,7 +112,7 @@ ssh_dss_verify(
         DSA_SIG *sig;
         EVP_MD *evp_md = EVP_sha1();
         EVP_MD_CTX md;
-        u_char *digest, *sigblob;
+        u_char digest[EVP_MAX_MD_SIZE], *sigblob;
         u_int len, dlen;
         int rlen, ret;
         Buffer b;
@@ -173,16 +170,13 @@ ssh_dss_verify(
         }
 
         /* sha1 the data */
-        dlen = evp_md->md_size;
-        digest = xmalloc(dlen);
         EVP_DigestInit(&md, evp_md);
         EVP_DigestUpdate(&md, data, datalen);
-        EVP_DigestFinal(&md, digest, NULL);
+        EVP_DigestFinal(&md, digest, &dlen);
 
         ret = DSA_do_verify(digest, dlen, sig, key->dsa);
+        memset(digest, 'd', sizeof(digest));
 
-        memset(digest, 0, dlen);
-        xfree(digest);
         DSA_SIG_free(sig);
 
         debug("ssh_dss_verify: signature %s",