Merge upstream-master into master

Commit ecb2c02d994b3e21994f31a70ff911667c262f1f upstream

This nearly (but not quite) corresponds to V_8_3_P1; subsequent
cherry-picks will correct this.

Bug: 162492243
Change-Id: I3c079d86435b7c25aefff4538dc89a3002b1e25b

1 files changed, 27 insertions, 19 deletions

diff --git a/ssh-ecdsa.c b/ssh-ecdsa.c
index 2c76f8b4..599c7199 100644
--- a/ssh-ecdsa.c
+++ b/ssh-ecdsa.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-ecdsa.c,v 1.11 2014/06/24 01:13:21 djm Exp $ */
+/* $OpenBSD: ssh-ecdsa.c,v 1.16 2019/01/21 09:54:11 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -43,12 +43,15 @@
 #define SSHKEY_INTERNAL
 #include "sshkey.h"
 
+#include "openbsd-compat/openssl-compat.h"
+
 /* ARGSUSED */
 int
 ssh_ecdsa_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
     const u_char *data, size_t datalen, u_int compat)
 {
 	ECDSA_SIG *sig = NULL;
+	const BIGNUM *sig_r, *sig_s;
 	int hash_alg;
 	u_char digest[SSH_DIGEST_MAX_LENGTH];
 	size_t len, dlen;
@@ -80,8 +83,9 @@ ssh_ecdsa_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
 		ret = SSH_ERR_ALLOC_FAIL;
 		goto out;
 	}
-	if ((ret = sshbuf_put_bignum2(bb, sig->r)) != 0 ||
-	    (ret = sshbuf_put_bignum2(bb, sig->s)) != 0)
+	ECDSA_SIG_get0(sig, &sig_r, &sig_s);
+	if ((ret = sshbuf_put_bignum2(bb, sig_r)) != 0 ||
+	    (ret = sshbuf_put_bignum2(bb, sig_s)) != 0)
 		goto out;
 	if ((ret = sshbuf_put_cstring(b, sshkey_ssh_name_plain(key))) != 0 ||
 	    (ret = sshbuf_put_stringb(b, bb)) != 0)
@@ -99,12 +103,9 @@ ssh_ecdsa_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
 	ret = 0;
  out:
 	explicit_bzero(digest, sizeof(digest));
-	if (b != NULL)
-		sshbuf_free(b);
-	if (bb != NULL)
-		sshbuf_free(bb);
-	if (sig != NULL)
-		ECDSA_SIG_free(sig);
+	sshbuf_free(b);
+	sshbuf_free(bb);
+	ECDSA_SIG_free(sig);
 	return ret;
 }
 
@@ -115,6 +116,7 @@ ssh_ecdsa_verify(const struct sshkey *key,
     const u_char *data, size_t datalen, u_int compat)
 {
 	ECDSA_SIG *sig = NULL;
+	BIGNUM *sig_r = NULL, *sig_s = NULL;
 	int hash_alg;
 	u_char digest[SSH_DIGEST_MAX_LENGTH];
 	size_t dlen;
@@ -123,7 +125,8 @@ ssh_ecdsa_verify(const struct sshkey *key,
 	char *ktype = NULL;
 
 	if (key == NULL || key->ecdsa == NULL ||
-	    sshkey_type_plain(key->type) != KEY_ECDSA)
+	    sshkey_type_plain(key->type) != KEY_ECDSA ||
+	    signature == NULL || signaturelen == 0)
 		return SSH_ERR_INVALID_ARGUMENT;
 
 	if ((hash_alg = sshkey_ec_nid_to_hash_alg(key->ecdsa_nid)) == -1 ||
@@ -148,15 +151,21 @@ ssh_ecdsa_verify(const struct sshkey *key,
 	}
 
 	/* parse signature */
+	if (sshbuf_get_bignum2(sigbuf, &sig_r) != 0 ||
+	    sshbuf_get_bignum2(sigbuf, &sig_s) != 0) {
+		ret = SSH_ERR_INVALID_FORMAT;
+		goto out;
+	}
 	if ((sig = ECDSA_SIG_new()) == NULL) {
 		ret = SSH_ERR_ALLOC_FAIL;
 		goto out;
 	}
-	if (sshbuf_get_bignum2(sigbuf, sig->r) != 0 ||
-	    sshbuf_get_bignum2(sigbuf, sig->s) != 0) {
-		ret = SSH_ERR_INVALID_FORMAT;
+	if (!ECDSA_SIG_set0(sig, sig_r, sig_s)) {
+		ret = SSH_ERR_LIBCRYPTO_ERROR;
 		goto out;
 	}
+	sig_r = sig_s = NULL; /* transferred */
+
 	if (sshbuf_len(sigbuf) != 0) {
 		ret = SSH_ERR_UNEXPECTED_TRAILING_DATA;
 		goto out;
@@ -179,12 +188,11 @@ ssh_ecdsa_verify(const struct sshkey *key,
 
  out:
 	explicit_bzero(digest, sizeof(digest));
-	if (sigbuf != NULL)
-		sshbuf_free(sigbuf);
-	if (b != NULL)
-		sshbuf_free(b);
-	if (sig != NULL)
-		ECDSA_SIG_free(sig);
+	sshbuf_free(sigbuf);
+	sshbuf_free(b);
+	ECDSA_SIG_free(sig);
+	BN_clear_free(sig_r);
+	BN_clear_free(sig_s);
 	free(ktype);
 	return ret;
 }