- markus@cvs.openbsd.org 2002/01/13 17:57:37

[openssh.git] / kexdh.c

diff --git a/kexdh.c b/kexdh.c
index 7b6a22040a3e33016817ecec1e0d76dcc0c7aee0..bc4700a2e38449d5ad2dac33169bdefec413ea1e 100644 (file)
--- a/kexdh.c
+++ b/kexdh.c
@@ -23,7 +23,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: kexdh.c,v 1.3 2001/04/04 09:48:34 markus Exp $");
+RCSID("$OpenBSD: kexdh.c,v 1.12 2001/12/28 14:50:54 markus Exp $");
 
 #include <openssl/crypto.h>
 #include <openssl/bn.h>
@@ -38,13 +38,13 @@ RCSID("$OpenBSD: kexdh.c,v 1.3 2001/04/04 09:48:34 markus Exp $");
 #include "dh.h"
 #include "ssh2.h"
 
-u_char *
+static u_char *
 kex_dh_hash(
     char *client_version_string,
     char *server_version_string,
     char *ckexinit, int ckexinitlen,
     char *skexinit, int skexinitlen,
-    char *serverhostkeyblob, int sbloblen,
+    u_char *serverhostkeyblob, int sbloblen,
     BIGNUM *client_dh_pub,
     BIGNUM *server_dh_pub,
     BIGNUM *shared_secret)
@@ -55,8 +55,8 @@ kex_dh_hash(
        EVP_MD_CTX md;
 
        buffer_init(&b);
-       buffer_put_string(&b, client_version_string, strlen(client_version_string));
-       buffer_put_string(&b, server_version_string, strlen(server_version_string));
+       buffer_put_cstring(&b, client_version_string);
+       buffer_put_cstring(&b, server_version_string);
 
        /* kexinit messages: fake header: len+SSH2_MSG_KEXINIT */
        buffer_put_int(&b, ckexinitlen+1);
@@ -88,16 +88,15 @@ kex_dh_hash(
 
 /* client */
 
-void
+static void
 kexdh_client(Kex *kex)
 {
        BIGNUM *dh_server_pub = NULL, *shared_secret = NULL;
        DH *dh;
        Key *server_host_key;
-       char *server_host_key_blob = NULL, *signature = NULL;
+       u_char *server_host_key_blob = NULL, *signature = NULL;
        u_char *kbuf, *hash;
        u_int klen, kout, slen, sbloblen;
-       int dlen, plen;
 
        /* generate and send 'e', client DH public key */
        dh = dh_new_group1();
@@ -115,7 +114,7 @@ kexdh_client(Kex *kex)
 #endif
 
        debug("expecting SSH2_MSG_KEXDH_REPLY");
-       packet_read_expect(&plen, SSH2_MSG_KEXDH_REPLY);
+       packet_read_expect(SSH2_MSG_KEXDH_REPLY);
 
        /* key, cert */
        server_host_key_blob = packet_get_string(&sbloblen);
@@ -123,15 +122,15 @@ kexdh_client(Kex *kex)
        if (server_host_key == NULL)
                fatal("cannot decode server_host_key_blob");
 
-       if (kex->check_host_key == NULL)
-               fatal("cannot check server_host_key");
-       kex->check_host_key(server_host_key);
+       if (kex->verify_host_key == NULL)
+               fatal("cannot verify server_host_key");
+       if (kex->verify_host_key(server_host_key) == -1)
+               fatal("server_host_key verification failed");
 
        /* DH paramter f, server public DH key */
-       dh_server_pub = BN_new();
-       if (dh_server_pub == NULL)
+       if ((dh_server_pub = BN_new()) == NULL)
                fatal("dh_server_pub == NULL");
-       packet_get_bignum2(dh_server_pub, &dlen);
+       packet_get_bignum2(dh_server_pub);
 
 #ifdef DEBUG_KEXDH
        fprintf(stderr, "dh_server_pub= ");
@@ -142,7 +141,7 @@ kexdh_client(Kex *kex)
 
        /* signed H */
        signature = packet_get_string(&slen);
-       packet_done();
+       packet_check_eom();
 
        if (!dh_pub_is_valid(dh, dh_server_pub))
                packet_disconnect("bad server public DH value");
@@ -153,7 +152,8 @@ kexdh_client(Kex *kex)
 #ifdef DEBUG_KEXDH
        dump_digest("shared secret", kbuf, kout);
 #endif
-       shared_secret = BN_new();
+       if ((shared_secret = BN_new()) == NULL)
+               fatal("kexdh_client: BN_new failed");
        BN_bin2bn(kbuf, kout, shared_secret);
        memset(kbuf, 0, klen);
        xfree(kbuf);
@@ -170,10 +170,10 @@ kexdh_client(Kex *kex)
            shared_secret
        );
        xfree(server_host_key_blob);
-       BN_free(dh_server_pub);
+       BN_clear_free(dh_server_pub);
        DH_free(dh);
 
-       if (key_verify(server_host_key, (u_char *)signature, slen, hash, 20) != 1)
+       if (key_verify(server_host_key, signature, slen, hash, 20) != 1)
                fatal("key_verify failed for server_host_key");
        key_free(server_host_key);
        xfree(signature);
@@ -192,7 +192,7 @@ kexdh_client(Kex *kex)
 
 /* server */
 
-void
+static void
 kexdh_server(Kex *kex)
 {
        BIGNUM *shared_secret = NULL, *dh_client_pub = NULL;
@@ -200,14 +200,14 @@ kexdh_server(Kex *kex)
        Key *server_host_key;
        u_char *kbuf, *hash, *signature = NULL, *server_host_key_blob = NULL;
        u_int sbloblen, klen, kout;
-       int dlen, slen, plen;
+       int slen;
 
        /* generate server DH public key */
        dh = dh_new_group1();
        dh_gen_key(dh, kex->we_need * 8);
 
        debug("expecting SSH2_MSG_KEXDH_INIT");
-       packet_read_expect(&plen, SSH2_MSG_KEXDH_INIT);
+       packet_read_expect(SSH2_MSG_KEXDH_INIT);
 
        if (kex->load_host_key == NULL)
                fatal("Cannot load hostkey");
@@ -216,10 +216,9 @@ kexdh_server(Kex *kex)
                fatal("Unsupported hostkey type %d", kex->hostkey_type);
 
        /* key, cert */
-       dh_client_pub = BN_new();
-       if (dh_client_pub == NULL)
+       if ((dh_client_pub = BN_new()) == NULL)
                fatal("dh_client_pub == NULL");
-       packet_get_bignum2(dh_client_pub, &dlen);
+       packet_get_bignum2(dh_client_pub);
 
 #ifdef DEBUG_KEXDH
        fprintf(stderr, "dh_client_pub= ");
@@ -243,7 +242,8 @@ kexdh_server(Kex *kex)
 #ifdef DEBUG_KEXDH
        dump_digest("shared secret", kbuf, kout);
 #endif
-       shared_secret = BN_new();
+       if ((shared_secret = BN_new()) == NULL)
+               fatal("kexdh_server: BN_new failed");
        BN_bin2bn(kbuf, kout, shared_secret);
        memset(kbuf, 0, klen);
        xfree(kbuf);
@@ -256,12 +256,12 @@ kexdh_server(Kex *kex)
            kex->server_version_string,
            buffer_ptr(&kex->peer), buffer_len(&kex->peer),
            buffer_ptr(&kex->my), buffer_len(&kex->my),
-           (char *)server_host_key_blob, sbloblen,
+           server_host_key_blob, sbloblen,
            dh_client_pub,
            dh->pub_key,
            shared_secret
        );
-       BN_free(dh_client_pub);
+       BN_clear_free(dh_client_pub);
 
        /* save session id := H */
        /* XXX hashlen depends on KEX */
@@ -279,9 +279,9 @@ kexdh_server(Kex *kex)
 
        /* send server hostkey, DH pubkey 'f' and singed H */
        packet_start(SSH2_MSG_KEXDH_REPLY);
-       packet_put_string((char *)server_host_key_blob, sbloblen);
+       packet_put_string(server_host_key_blob, sbloblen);
        packet_put_bignum2(dh->pub_key);        /* f */
-       packet_put_string((char *)signature, slen);
+       packet_put_string(signature, slen);
        packet_send();
 
        xfree(signature);