- djm@cvs.openbsd.org 2014/06/24 01:13:21
     [Makefile.in auth-bsdauth.c auth-chall.c auth-options.c auth-rsa.c
     [auth2-none.c auth2-pubkey.c authfile.c authfile.h cipher-3des1.c
     [cipher-chachapoly.c cipher-chachapoly.h cipher.c cipher.h
     [digest-libc.c digest-openssl.c digest.h dns.c entropy.c hmac.h
     [hostfile.c key.c key.h krl.c monitor.c packet.c rsa.c rsa.h
     [ssh-add.c ssh-agent.c ssh-dss.c ssh-ecdsa.c ssh-ed25519.c
     [ssh-keygen.c ssh-pkcs11-client.c ssh-pkcs11-helper.c ssh-pkcs11.c
     [ssh-rsa.c sshbuf-misc.c sshbuf.h sshconnect.c sshconnect1.c
     [sshconnect2.c sshd.c sshkey.c sshkey.h
     [openbsd-compat/openssl-compat.c openbsd-compat/openssl-compat.h]
     New key API: refactor key-related functions to be more library-like,
     existing API is offered as a set of wrappers.

     with and ok markus@

     Thanks also to Ben Hawkes, David Tomaschik, Ivan Fratric, Matthew
     Dempsky and Ron Bowes for a detailed review a few months ago.

     NB. This commit also removes portable OpenSSH support for OpenSSL
     <0.9.8e.
diff --git a/ssh-ed25519.c b/ssh-ed25519.c
index 160d1f2..cb87d47 100644
--- a/ssh-ed25519.c
+++ b/ssh-ed25519.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-ed25519.c,v 1.3 2014/02/23 20:03:42 djm Exp $ */
+/* $OpenBSD: ssh-ed25519.c,v 1.4 2014/06/24 01:13:21 djm Exp $ */
 /*
  * Copyright (c) 2013 Markus Friedl <markus@openbsd.org>
  *
@@ -18,132 +18,149 @@
 #include "includes.h"
 
 #include <sys/types.h>
+#include <limits.h>
 
 #include "crypto_api.h"
 
-#include <limits.h>
 #include <string.h>
 #include <stdarg.h>
 
 #include "xmalloc.h"
 #include "log.h"
 #include "buffer.h"
-#include "key.h"
+#define SSHKEY_INTERNAL
+#include "sshkey.h"
+#include "ssherr.h"
 #include "ssh.h"
 
 int
-ssh_ed25519_sign(const Key *key, u_char **sigp, u_int *lenp,
-    const u_char *data, u_int datalen)
+ssh_ed25519_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
+    const u_char *data, size_t datalen, u_int compat)
 {
-	u_char *sig;
-	u_int slen, len;
+	u_char *sig = NULL;
+	size_t slen = 0, len;
 	unsigned long long smlen;
-	int ret;
-	Buffer b;
+	int r, ret;
+	struct sshbuf *b = NULL;
 
-	if (key == NULL || key_type_plain(key->type) != KEY_ED25519 ||
-	    key->ed25519_sk == NULL) {
-		error("%s: no ED25519 key", __func__);
-		return -1;
-	}
+	if (lenp != NULL)
+		*lenp = 0;
+	if (sigp != NULL)
+		*sigp = NULL;
 
-	if (datalen >= UINT_MAX - crypto_sign_ed25519_BYTES) {
-		error("%s: datalen %u too long", __func__, datalen);
-		return -1;
-	}
+	if (key == NULL ||
+	    sshkey_type_plain(key->type) != KEY_ED25519 ||
+	    key->ed25519_sk == NULL ||
+	    datalen >= INT_MAX - crypto_sign_ed25519_BYTES)
+		return SSH_ERR_INVALID_ARGUMENT;
 	smlen = slen = datalen + crypto_sign_ed25519_BYTES;
-	sig = xmalloc(slen);
+	if ((sig = malloc(slen)) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
 
 	if ((ret = crypto_sign_ed25519(sig, &smlen, data, datalen,
 	    key->ed25519_sk)) != 0 || smlen <= datalen) {
-		error("%s: crypto_sign_ed25519 failed: %d", __func__, ret);
-		free(sig);
-		return -1;
+		r = SSH_ERR_INVALID_ARGUMENT; /* XXX better error? */
+		goto out;
 	}
 	/* encode signature */
-	buffer_init(&b);
-	buffer_put_cstring(&b, "ssh-ed25519");
-	buffer_put_string(&b, sig, smlen - datalen);
-	len = buffer_len(&b);
+	if ((b = sshbuf_new()) == NULL) {
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	if ((r = sshbuf_put_cstring(b, "ssh-ed25519")) != 0 ||
+	    (r = sshbuf_put_string(b, sig, smlen - datalen)) != 0)
+		goto out;
+	len = sshbuf_len(b);
+	if (sigp != NULL) {
+		if ((*sigp = malloc(len)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		memcpy(*sigp, sshbuf_ptr(b), len);
+	}
 	if (lenp != NULL)
 		*lenp = len;
-	if (sigp != NULL) {
-		*sigp = xmalloc(len);
-		memcpy(*sigp, buffer_ptr(&b), len);
+	/* success */
+	r = 0;
+ out:
+	sshbuf_free(b);
+	if (sig != NULL) {
+		explicit_bzero(sig, slen);
+		free(sig);
 	}
-	buffer_free(&b);
-	explicit_bzero(sig, slen);
-	free(sig);
 
-	return 0;
+	return r;
 }
 
 int
-ssh_ed25519_verify(const Key *key, const u_char *signature, u_int signaturelen,
-    const u_char *data, u_int datalen)
+ssh_ed25519_verify(const struct sshkey *key,
+    const u_char *signature, size_t signaturelen,
+    const u_char *data, size_t datalen, u_int compat)
 {
-	Buffer b;
-	char *ktype;
-	u_char *sigblob, *sm, *m;
-	u_int len;
-	unsigned long long smlen, mlen;
-	int rlen, ret;
+	struct sshbuf *b = NULL;
+	char *ktype = NULL;
+	const u_char *sigblob;
+	u_char *sm = NULL, *m = NULL;
+	size_t len;
+	unsigned long long smlen = 0, mlen = 0;
+	int r, ret;
 
-	if (key == NULL || key_type_plain(key->type) != KEY_ED25519 ||
-	    key->ed25519_pk == NULL) {
-		error("%s: no ED25519 key", __func__);
-		return -1;
-	}
-	buffer_init(&b);
-	buffer_append(&b, signature, signaturelen);
-	ktype = buffer_get_cstring(&b, NULL);
+	if (key == NULL ||
+	    sshkey_type_plain(key->type) != KEY_ED25519 ||
+	    key->ed25519_pk == NULL ||
+	    datalen >= INT_MAX - crypto_sign_ed25519_BYTES)
+		return SSH_ERR_INVALID_ARGUMENT;
+
+	if ((b = sshbuf_from(signature, signaturelen)) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+	if ((r = sshbuf_get_cstring(b, &ktype, NULL)) != 0 ||
+	    (r = sshbuf_get_string_direct(b, &sigblob, &len)) != 0)
+		goto out;
 	if (strcmp("ssh-ed25519", ktype) != 0) {
-		error("%s: cannot handle type %s", __func__, ktype);
-		buffer_free(&b);
-		free(ktype);
-		return -1;
+		r = SSH_ERR_KEY_TYPE_MISMATCH;
+		goto out;
 	}
-	free(ktype);
-	sigblob = buffer_get_string(&b, &len);
-	rlen = buffer_len(&b);
-	buffer_free(&b);
-	if (rlen != 0) {
-		error("%s: remaining bytes in signature %d", __func__, rlen);
-		free(sigblob);
-		return -1;
+	if (sshbuf_len(b) != 0) {
+		r = SSH_ERR_UNEXPECTED_TRAILING_DATA;
+		goto out;
 	}
 	if (len > crypto_sign_ed25519_BYTES) {
-		error("%s: len %u > crypto_sign_ed25519_BYTES %u", __func__,
-		    len, crypto_sign_ed25519_BYTES);
-		free(sigblob);
-		return -1;
+		r = SSH_ERR_INVALID_FORMAT;
+		goto out;
 	}
+	if (datalen >= SIZE_MAX - len)
+		return SSH_ERR_INVALID_ARGUMENT;
 	smlen = len + datalen;
-	sm = xmalloc(smlen);
+	mlen = smlen;
+	if ((sm = malloc(smlen)) == NULL || (m = xmalloc(mlen)) == NULL) {
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
 	memcpy(sm, sigblob, len);
 	memcpy(sm+len, data, datalen);
-	mlen = smlen;
-	m = xmalloc(mlen);
 	if ((ret = crypto_sign_ed25519_open(m, &mlen, sm, smlen,
 	    key->ed25519_pk)) != 0) {
 		debug2("%s: crypto_sign_ed25519_open failed: %d",
 		    __func__, ret);
 	}
-	if (ret == 0 && mlen != datalen) {
-		debug2("%s: crypto_sign_ed25519_open "
-		    "mlen != datalen (%llu != %u)", __func__, mlen, datalen);
-		ret = -1;
+	if (ret != 0 || mlen != datalen) {
+		r = SSH_ERR_SIGNATURE_INVALID;
+		goto out;
 	}
 	/* XXX compare 'm' and 'data' ? */
-
-	explicit_bzero(sigblob, len);
-	explicit_bzero(sm, smlen);
-	explicit_bzero(m, smlen); /* NB. mlen may be invalid if ret != 0 */
-	free(sigblob);
-	free(sm);
-	free(m);
-	debug("%s: signature %scorrect", __func__, (ret != 0) ? "in" : "");
-
-	/* translate return code carefully */
-	return (ret == 0) ? 1 : -1;
+	/* success */
+	r = 0;
+ out:
+	if (sm != NULL) {
+		explicit_bzero(sm, smlen);
+		free(sm);
+	}
+	if (m != NULL) {
+		explicit_bzero(m, smlen); /* NB mlen may be invalid if r != 0 */
+		free(m);
+	}
+	sshbuf_free(b);
+	free(ktype);
+	return r;
 }
+