upstream commit
adapt kex to sshbuf and struct ssh; ok djm@
diff --git a/kexdhs.c b/kexdhs.c
index 34a215f..182657a 100644
--- a/kexdhs.c
+++ b/kexdhs.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexdhs.c,v 1.19 2015/01/19 19:52:16 markus Exp $ */
+/* $OpenBSD: kexdhs.c,v 1.20 2015/01/19 20:16:15 markus Exp $ */
/*
* Copyright (c) 2001 Markus Friedl. All rights reserved.
*
@@ -35,55 +35,88 @@
#include <openssl/dh.h>
-#include "xmalloc.h"
-#include "buffer.h"
-#include "key.h"
+#include "sshkey.h"
#include "cipher.h"
+#include "digest.h"
#include "kex.h"
#include "log.h"
#include "packet.h"
#include "dh.h"
#include "ssh2.h"
-void
-kexdh_server(Kex *kex)
+#include "dispatch.h"
+#include "compat.h"
+#include "ssherr.h"
+#include "sshbuf.h"
+
+static int input_kex_dh_init(int, u_int32_t, void *);
+
+int
+kexdh_server(struct ssh *ssh)
{
- BIGNUM *shared_secret = NULL, *dh_client_pub = NULL;
- DH *dh;
- Key *server_host_public, *server_host_private;
- u_char *kbuf, *hash, *signature = NULL, *server_host_key_blob = NULL;
- u_int sbloblen, klen, hashlen, slen;
- int kout;
+ struct kex *kex = ssh->kex;
+ int r;
/* generate server DH public key */
switch (kex->kex_type) {
case KEX_DH_GRP1_SHA1:
- dh = dh_new_group1();
+ kex->dh = dh_new_group1();
break;
case KEX_DH_GRP14_SHA1:
- dh = dh_new_group14();
+ kex->dh = dh_new_group14();
break;
default:
- fatal("%s: Unexpected KEX type %d", __func__, kex->kex_type);
+ r = SSH_ERR_INVALID_ARGUMENT;
+ goto out;
}
- dh_gen_key(dh, kex->we_need * 8);
+ if (kex->dh == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto out;
+ }
+ if ((r = dh_gen_key(kex->dh, kex->we_need * 8)) != 0)
+ goto out;
debug("expecting SSH2_MSG_KEXDH_INIT");
- packet_read_expect(SSH2_MSG_KEXDH_INIT);
+ ssh_dispatch_set(ssh, SSH2_MSG_KEXDH_INIT, &input_kex_dh_init);
+ r = 0;
+ out:
+ return r;
+}
+
+int
+input_kex_dh_init(int type, u_int32_t seq, void *ctxt)
+{
+ struct ssh *ssh = ctxt;
+ struct kex *kex = ssh->kex;
+ BIGNUM *shared_secret = NULL, *dh_client_pub = NULL;
+ struct sshkey *server_host_public, *server_host_private;
+ u_char *kbuf = NULL, *signature = NULL, *server_host_key_blob = NULL;
+ u_char hash[SSH_DIGEST_MAX_LENGTH];
+ size_t sbloblen, slen;
+ size_t klen = 0, hashlen;
+ int kout, r;
if (kex->load_host_public_key == NULL ||
- kex->load_host_private_key == NULL)
- fatal("Cannot load hostkey");
- server_host_public = kex->load_host_public_key(kex->hostkey_type);
- if (server_host_public == NULL)
- fatal("Unsupported hostkey type %d", kex->hostkey_type);
- server_host_private = kex->load_host_private_key(kex->hostkey_type);
+ kex->load_host_private_key == NULL) {
+ r = SSH_ERR_INVALID_ARGUMENT;
+ goto out;
+ }
+ if ((server_host_public = kex->load_host_public_key(kex->hostkey_type,
+ ssh)) == NULL ||
+ (server_host_private = kex->load_host_private_key(kex->hostkey_type,
+ ssh)) == NULL) {
+ r = SSH_ERR_NO_HOSTKEY_LOADED;
+ goto out;
+ }
/* key, cert */
- if ((dh_client_pub = BN_new()) == NULL)
- fatal("dh_client_pub == NULL");
- packet_get_bignum2(dh_client_pub);
- packet_check_eom();
+ if ((dh_client_pub = BN_new()) == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto out;
+ }
+ if ((r = sshpkt_get_bignum2(ssh, dh_client_pub)) != 0 ||
+ (r = sshpkt_get_end(ssh)) != 0)
+ goto out;
#ifdef DEBUG_KEXDH
fprintf(stderr, "dh_client_pub= ");
@@ -93,71 +126,90 @@
#endif
#ifdef DEBUG_KEXDH
- DHparams_print_fp(stderr, dh);
+ DHparams_print_fp(stderr, kex->dh);
fprintf(stderr, "pub= ");
- BN_print_fp(stderr, dh->pub_key);
+ BN_print_fp(stderr, kex->dh->pub_key);
fprintf(stderr, "\n");
#endif
- if (!dh_pub_is_valid(dh, dh_client_pub))
- packet_disconnect("bad client public DH value");
+ if (!dh_pub_is_valid(kex->dh, dh_client_pub)) {
+ sshpkt_disconnect(ssh, "bad client public DH value");
+ r = SSH_ERR_MESSAGE_INCOMPLETE;
+ goto out;
+ }
- klen = DH_size(dh);
- kbuf = xmalloc(klen);
- if ((kout = DH_compute_key(kbuf, dh_client_pub, dh)) < 0)
- fatal("DH_compute_key: failed");
+ klen = DH_size(kex->dh);
+ if ((kbuf = malloc(klen)) == NULL ||
+ (shared_secret = BN_new()) == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto out;
+ }
+ if ((kout = DH_compute_key(kbuf, dh_client_pub, kex->dh)) < 0 ||
+ BN_bin2bn(kbuf, kout, shared_secret) == NULL) {
+ r = SSH_ERR_LIBCRYPTO_ERROR;
+ goto out;
+ }
#ifdef DEBUG_KEXDH
dump_digest("shared secret", kbuf, kout);
#endif
- if ((shared_secret = BN_new()) == NULL)
- fatal("kexdh_server: BN_new failed");
- if (BN_bin2bn(kbuf, kout, shared_secret) == NULL)
- fatal("kexdh_server: BN_bin2bn failed");
- explicit_bzero(kbuf, klen);
- free(kbuf);
-
- key_to_blob(server_host_public, &server_host_key_blob, &sbloblen);
-
+ if ((r = sshkey_to_blob(server_host_public, &server_host_key_blob,
+ &sbloblen)) != 0)
+ goto out;
/* calc H */
- kex_dh_hash(
+ hashlen = sizeof(hash);
+ if ((r = kex_dh_hash(
kex->client_version_string,
kex->server_version_string,
- buffer_ptr(kex->peer), buffer_len(kex->peer),
- buffer_ptr(kex->my), buffer_len(kex->my),
+ sshbuf_ptr(kex->peer), sshbuf_len(kex->peer),
+ sshbuf_ptr(kex->my), sshbuf_len(kex->my),
server_host_key_blob, sbloblen,
dh_client_pub,
- dh->pub_key,
+ kex->dh->pub_key,
shared_secret,
- &hash, &hashlen
- );
- BN_clear_free(dh_client_pub);
+ hash, &hashlen)) != 0)
+ goto out;
/* save session id := H */
if (kex->session_id == NULL) {
kex->session_id_len = hashlen;
- kex->session_id = xmalloc(kex->session_id_len);
+ kex->session_id = malloc(kex->session_id_len);
+ if (kex->session_id == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto out;
+ }
memcpy(kex->session_id, hash, kex->session_id_len);
}
/* sign H */
- kex->sign(server_host_private, server_host_public, &signature, &slen,
- hash, hashlen);
+ if ((r = kex->sign(server_host_private, server_host_public,
+ &signature, &slen, hash, hashlen, ssh->compat)) < 0)
+ goto out;
/* destroy_sensitive_data(); */
/* send server hostkey, DH pubkey 'f' and singed H */
- packet_start(SSH2_MSG_KEXDH_REPLY);
- packet_put_string(server_host_key_blob, sbloblen);
- packet_put_bignum2(dh->pub_key); /* f */
- packet_put_string(signature, slen);
- packet_send();
+ if ((r = sshpkt_start(ssh, SSH2_MSG_KEXDH_REPLY)) != 0 ||
+ (r = sshpkt_put_string(ssh, server_host_key_blob, sbloblen)) != 0 ||
+ (r = sshpkt_put_bignum2(ssh, kex->dh->pub_key)) != 0 || /* f */
+ (r = sshpkt_put_string(ssh, signature, slen)) != 0 ||
+ (r = sshpkt_send(ssh)) != 0)
+ goto out;
- free(signature);
+ if ((r = kex_derive_keys_bn(ssh, hash, hashlen, shared_secret)) == 0)
+ r = kex_send_newkeys(ssh);
+ out:
+ explicit_bzero(hash, sizeof(hash));
+ DH_free(kex->dh);
+ kex->dh = NULL;
+ if (dh_client_pub)
+ BN_clear_free(dh_client_pub);
+ if (kbuf) {
+ explicit_bzero(kbuf, klen);
+ free(kbuf);
+ }
+ if (shared_secret)
+ BN_clear_free(shared_secret);
free(server_host_key_blob);
- /* have keys, free DH */
- DH_free(dh);
-
- kex_derive_keys_bn(kex, hash, hashlen, shared_secret);
- BN_clear_free(shared_secret);
- kex_finish(kex);
+ free(signature);
+ return r;
}
#endif /* WITH_OPENSSL */