X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/714954dcea40f414494c6527df6d62d2295b4fd6..HEAD:/ssh-dss.c

diff --git a/ssh-dss.c b/ssh-dss.c
index 02403f55..51a06e98 100644
--- a/ssh-dss.c
+++ b/ssh-dss.c
@@ -1,3 +1,4 @@
+/* $OpenBSD: ssh-dss.c,v 1.24 2006/11/06 21:25:28 markus Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  *
@@ -23,32 +24,32 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: ssh-dss.c,v 1.14 2002/02/28 15:46:33 markus Exp $");
+
+#include <sys/types.h>
 
 #include <openssl/bn.h>
 #include <openssl/evp.h>
 
+#include <stdarg.h>
+#include <string.h>
+
 #include "xmalloc.h"
 #include "buffer.h"
-#include "bufaux.h"
 #include "compat.h"
 #include "log.h"
 #include "key.h"
-#include "ssh-dss.h"
 
 #define INTBLOB_LEN	20
 #define SIGBLOB_LEN	(2*INTBLOB_LEN)
 
 int
-ssh_dss_sign(
-    Key *key,
-    u_char **sigp, u_int *lenp,
-    u_char *data, u_int datalen)
+ssh_dss_sign(const Key *key, u_char **sigp, u_int *lenp,
+    const u_char *data, u_int datalen)
 {
 	DSA_SIG *sig;
 	const EVP_MD *evp_md = EVP_sha1();
 	EVP_MD_CTX md;
-	u_char *ret, digest[EVP_MAX_MD_SIZE], sigblob[SIGBLOB_LEN];
+	u_char digest[EVP_MAX_MD_SIZE], sigblob[SIGBLOB_LEN];
 	u_int rlen, slen, len, dlen;
 	Buffer b;
 
@@ -71,7 +72,7 @@ ssh_dss_sign(
 	rlen = BN_num_bytes(sig->r);
 	slen = BN_num_bytes(sig->s);
 	if (rlen > INTBLOB_LEN || slen > INTBLOB_LEN) {
-		error("bad sig size %d %d", rlen, slen);
+		error("bad sig size %u %u", rlen, slen);
 		DSA_SIG_free(sig);
 		return -1;
 	}
@@ -81,33 +82,31 @@ ssh_dss_sign(
 	DSA_SIG_free(sig);
 
 	if (datafellows & SSH_BUG_SIGBLOB) {
-		ret = xmalloc(SIGBLOB_LEN);
-		memcpy(ret, sigblob, SIGBLOB_LEN);
 		if (lenp != NULL)
 			*lenp = SIGBLOB_LEN;
-		if (sigp != NULL)
-			*sigp = ret;
+		if (sigp != NULL) {
+			*sigp = xmalloc(SIGBLOB_LEN);
+			memcpy(*sigp, sigblob, SIGBLOB_LEN);
+		}
 	} else {
 		/* ietf-drafts */
 		buffer_init(&b);
 		buffer_put_cstring(&b, "ssh-dss");
 		buffer_put_string(&b, sigblob, SIGBLOB_LEN);
 		len = buffer_len(&b);
-		ret = xmalloc(len);
-		memcpy(ret, buffer_ptr(&b), len);
-		buffer_free(&b);
 		if (lenp != NULL)
 			*lenp = len;
-		if (sigp != NULL)
-			*sigp = ret;
+		if (sigp != NULL) {
+			*sigp = xmalloc(len);
+			memcpy(*sigp, buffer_ptr(&b), len);
+		}
+		buffer_free(&b);
 	}
 	return 0;
 }
 int
-ssh_dss_verify(
-    Key *key,
-    u_char *signature, u_int signaturelen,
-    u_char *data, u_int datalen)
+ssh_dss_verify(const Key *key, const u_char *signature, u_int signaturelen,
+    const u_char *data, u_int datalen)
 {
 	DSA_SIG *sig;
 	const EVP_MD *evp_md = EVP_sha1();
@@ -124,7 +123,8 @@ ssh_dss_verify(
 
 	/* fetch signature */
 	if (datafellows & SSH_BUG_SIGBLOB) {
-		sigblob = signature;
+		sigblob = xmalloc(signaturelen);
+		memcpy(sigblob, signature, signaturelen);
 		len = signaturelen;
 	} else {
 		/* ietf-drafts */
@@ -151,7 +151,7 @@ ssh_dss_verify(
 	}
 
 	if (len != SIGBLOB_LEN) {
-		fatal("bad sigbloblen %d != SIGBLOB_LEN", len);
+		fatal("bad sigbloblen %u != SIGBLOB_LEN", len);
 	}
 
 	/* parse signature */
@@ -161,13 +161,13 @@ ssh_dss_verify(
 		fatal("ssh_dss_verify: BN_new failed");
 	if ((sig->s = BN_new()) == NULL)
 		fatal("ssh_dss_verify: BN_new failed");
-	BN_bin2bn(sigblob, INTBLOB_LEN, sig->r);
-	BN_bin2bn(sigblob+ INTBLOB_LEN, INTBLOB_LEN, sig->s);
+	if ((BN_bin2bn(sigblob, INTBLOB_LEN, sig->r) == NULL) ||
+	    (BN_bin2bn(sigblob+ INTBLOB_LEN, INTBLOB_LEN, sig->s) == NULL))
+		fatal("ssh_dss_verify: BN_bin2bn failed");
 
-	if (!(datafellows & SSH_BUG_SIGBLOB)) {
-		memset(sigblob, 0, len);
-		xfree(sigblob);
-	}
+	/* clean up */
+	memset(sigblob, 0, len);
+	xfree(sigblob);
 
 	/* sha1 the data */
 	EVP_DigestInit(&md, evp_md);