Adding upstream version 1:7.9p1.upstream/1%7.9p1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 265 insertions, 0 deletions

diff --git a/mac.c b/mac.c
new file mode 100644
index 0000000..51dc11d
--- /dev/null
+++ b/mac.c
@@ -0,0 +1,265 @@
+/* $OpenBSD: mac.c,v 1.34 2017/05/08 22:57:38 djm Exp $ */
+/*
+ * Copyright (c) 2001 Markus Friedl.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "includes.h"
+
+#include <sys/types.h>
+
+#include <string.h>
+#include <stdio.h>
+
+#include "digest.h"
+#include "hmac.h"
+#include "umac.h"
+#include "mac.h"
+#include "misc.h"
+#include "ssherr.h"
+#include "sshbuf.h"
+
+#include "openbsd-compat/openssl-compat.h"
+
+#define SSH_DIGEST	1	/* SSH_DIGEST_XXX */
+#define SSH_UMAC	2	/* UMAC (not integrated with OpenSSL) */
+#define SSH_UMAC128	3
+
+struct macalg {
+	char		*name;
+	int		type;
+	int		alg;
+	int		truncatebits;	/* truncate digest if != 0 */
+	int		key_len;	/* just for UMAC */
+	int		len;		/* just for UMAC */
+	int		etm;		/* Encrypt-then-MAC */
+};
+
+static const struct macalg macs[] = {
+	/* Encrypt-and-MAC (encrypt-and-authenticate) variants */
+	{ "hmac-sha1",				SSH_DIGEST, SSH_DIGEST_SHA1, 0, 0, 0, 0 },
+	{ "hmac-sha1-96",			SSH_DIGEST, SSH_DIGEST_SHA1, 96, 0, 0, 0 },
+#ifdef HAVE_EVP_SHA256
+	{ "hmac-sha2-256",			SSH_DIGEST, SSH_DIGEST_SHA256, 0, 0, 0, 0 },
+	{ "hmac-sha2-512",			SSH_DIGEST, SSH_DIGEST_SHA512, 0, 0, 0, 0 },
+#endif
+	{ "hmac-md5",				SSH_DIGEST, SSH_DIGEST_MD5, 0, 0, 0, 0 },
+	{ "hmac-md5-96",			SSH_DIGEST, SSH_DIGEST_MD5, 96, 0, 0, 0 },
+	{ "umac-64@openssh.com",		SSH_UMAC, 0, 0, 128, 64, 0 },
+	{ "umac-128@openssh.com",		SSH_UMAC128, 0, 0, 128, 128, 0 },
+
+	/* Encrypt-then-MAC variants */
+	{ "hmac-sha1-etm@openssh.com",		SSH_DIGEST, SSH_DIGEST_SHA1, 0, 0, 0, 1 },
+	{ "hmac-sha1-96-etm@openssh.com",	SSH_DIGEST, SSH_DIGEST_SHA1, 96, 0, 0, 1 },
+#ifdef HAVE_EVP_SHA256
+	{ "hmac-sha2-256-etm@openssh.com",	SSH_DIGEST, SSH_DIGEST_SHA256, 0, 0, 0, 1 },
+	{ "hmac-sha2-512-etm@openssh.com",	SSH_DIGEST, SSH_DIGEST_SHA512, 0, 0, 0, 1 },
+#endif
+	{ "hmac-md5-etm@openssh.com",		SSH_DIGEST, SSH_DIGEST_MD5, 0, 0, 0, 1 },
+	{ "hmac-md5-96-etm@openssh.com",	SSH_DIGEST, SSH_DIGEST_MD5, 96, 0, 0, 1 },
+	{ "umac-64-etm@openssh.com",		SSH_UMAC, 0, 0, 128, 64, 1 },
+	{ "umac-128-etm@openssh.com",		SSH_UMAC128, 0, 0, 128, 128, 1 },
+
+	{ NULL,					0, 0, 0, 0, 0, 0 }
+};
+
+/* Returns a list of supported MACs separated by the specified char. */
+char *
+mac_alg_list(char sep)
+{
+	char *ret = NULL, *tmp;
+	size_t nlen, rlen = 0;
+	const struct macalg *m;
+
+	for (m = macs; m->name != NULL; m++) {
+		if (ret != NULL)
+			ret[rlen++] = sep;
+		nlen = strlen(m->name);
+		if ((tmp = realloc(ret, rlen + nlen + 2)) == NULL) {
+			free(ret);
+			return NULL;
+		}
+		ret = tmp;
+		memcpy(ret + rlen, m->name, nlen + 1);
+		rlen += nlen;
+	}
+	return ret;
+}
+
+static int
+mac_setup_by_alg(struct sshmac *mac, const struct macalg *macalg)
+{
+	mac->type = macalg->type;
+	if (mac->type == SSH_DIGEST) {
+		if ((mac->hmac_ctx = ssh_hmac_start(macalg->alg)) == NULL)
+			return SSH_ERR_ALLOC_FAIL;
+		mac->key_len = mac->mac_len = ssh_hmac_bytes(macalg->alg);
+	} else {
+		mac->mac_len = macalg->len / 8;
+		mac->key_len = macalg->key_len / 8;
+		mac->umac_ctx = NULL;
+	}
+	if (macalg->truncatebits != 0)
+		mac->mac_len = macalg->truncatebits / 8;
+	mac->etm = macalg->etm;
+	return 0;
+}
+
+int
+mac_setup(struct sshmac *mac, char *name)
+{
+	const struct macalg *m;
+
+	for (m = macs; m->name != NULL; m++) {
+		if (strcmp(name, m->name) != 0)
+			continue;
+		if (mac != NULL)
+			return mac_setup_by_alg(mac, m);
+		return 0;
+	}
+	return SSH_ERR_INVALID_ARGUMENT;
+}
+
+int
+mac_init(struct sshmac *mac)
+{
+	if (mac->key == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+	switch (mac->type) {
+	case SSH_DIGEST:
+		if (mac->hmac_ctx == NULL ||
+		    ssh_hmac_init(mac->hmac_ctx, mac->key, mac->key_len) < 0)
+			return SSH_ERR_INVALID_ARGUMENT;
+		return 0;
+	case SSH_UMAC:
+		if ((mac->umac_ctx = umac_new(mac->key)) == NULL)
+			return SSH_ERR_ALLOC_FAIL;
+		return 0;
+	case SSH_UMAC128:
+		if ((mac->umac_ctx = umac128_new(mac->key)) == NULL)
+			return SSH_ERR_ALLOC_FAIL;
+		return 0;
+	default:
+		return SSH_ERR_INVALID_ARGUMENT;
+	}
+}
+
+int
+mac_compute(struct sshmac *mac, u_int32_t seqno,
+    const u_char *data, int datalen,
+    u_char *digest, size_t dlen)
+{
+	static union {
+		u_char m[SSH_DIGEST_MAX_LENGTH];
+		u_int64_t for_align;
+	} u;
+	u_char b[4];
+	u_char nonce[8];
+
+	if (mac->mac_len > sizeof(u))
+		return SSH_ERR_INTERNAL_ERROR;
+
+	switch (mac->type) {
+	case SSH_DIGEST:
+		put_u32(b, seqno);
+		/* reset HMAC context */
+		if (ssh_hmac_init(mac->hmac_ctx, NULL, 0) < 0 ||
+		    ssh_hmac_update(mac->hmac_ctx, b, sizeof(b)) < 0 ||
+		    ssh_hmac_update(mac->hmac_ctx, data, datalen) < 0 ||
+		    ssh_hmac_final(mac->hmac_ctx, u.m, sizeof(u.m)) < 0)
+			return SSH_ERR_LIBCRYPTO_ERROR;
+		break;
+	case SSH_UMAC:
+		POKE_U64(nonce, seqno);
+		umac_update(mac->umac_ctx, data, datalen);
+		umac_final(mac->umac_ctx, u.m, nonce);
+		break;
+	case SSH_UMAC128:
+		put_u64(nonce, seqno);
+		umac128_update(mac->umac_ctx, data, datalen);
+		umac128_final(mac->umac_ctx, u.m, nonce);
+		break;
+	default:
+		return SSH_ERR_INVALID_ARGUMENT;
+	}
+	if (digest != NULL) {
+		if (dlen > mac->mac_len)
+			dlen = mac->mac_len;
+		memcpy(digest, u.m, dlen);
+	}
+	return 0;
+}
+
+int
+mac_check(struct sshmac *mac, u_int32_t seqno,
+    const u_char *data, size_t dlen,
+    const u_char *theirmac, size_t mlen)
+{
+	u_char ourmac[SSH_DIGEST_MAX_LENGTH];
+	int r;
+
+	if (mac->mac_len > mlen)
+		return SSH_ERR_INVALID_ARGUMENT;
+	if ((r = mac_compute(mac, seqno, data, dlen,
+	    ourmac, sizeof(ourmac))) != 0)
+		return r;
+	if (timingsafe_bcmp(ourmac, theirmac, mac->mac_len) != 0)
+		return SSH_ERR_MAC_INVALID;
+	return 0;
+}
+
+void
+mac_clear(struct sshmac *mac)
+{
+	if (mac->type == SSH_UMAC) {
+		if (mac->umac_ctx != NULL)
+			umac_delete(mac->umac_ctx);
+	} else if (mac->type == SSH_UMAC128) {
+		if (mac->umac_ctx != NULL)
+			umac128_delete(mac->umac_ctx);
+	} else if (mac->hmac_ctx != NULL)
+		ssh_hmac_free(mac->hmac_ctx);
+	mac->hmac_ctx = NULL;
+	mac->umac_ctx = NULL;
+}
+
+/* XXX copied from ciphers_valid */
+#define	MAC_SEP	","
+int
+mac_valid(const char *names)
+{
+	char *maclist, *cp, *p;
+
+	if (names == NULL || strcmp(names, "") == 0)
+		return 0;
+	if ((maclist = cp = strdup(names)) == NULL)
+		return 0;
+	for ((p = strsep(&cp, MAC_SEP)); p && *p != '\0';
+	    (p = strsep(&cp, MAC_SEP))) {
+		if (mac_setup(NULL, p) < 0) {
+			free(maclist);
+			return 0;
+		}
+	}
+	free(maclist);
+	return 1;
+}