- markus@cvs.openbsd.org 2003/02/16 17:09:57

     [kex.c kexdh.c kexgex.c kex.h sshconnect2.c sshd.c ssh-keyscan.c]
     split kex into client and server code, no need to link
     server code into the client; ok provos@

1 files changed, 4 insertions, 230 deletions

diff --git a/kexdh.c b/kexdh.c
index 1e91e2550..4bbb7d1db 100644
--- a/kexdh.c
+++ b/kexdh.c
@@ -23,23 +23,16 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: kexdh.c,v 1.18 2002/03/18 17:50:31 provos Exp $");
+RCSID("$OpenBSD: kexdh.c,v 1.19 2003/02/16 17:09:57 markus Exp $");
 
-#include <openssl/crypto.h>
-#include <openssl/bn.h>
+#include <openssl/evp.h>
 
-#include "xmalloc.h"
 #include "buffer.h"
 #include "bufaux.h"
-#include "key.h"
-#include "kex.h"
-#include "log.h"
-#include "packet.h"
-#include "dh.h"
 #include "ssh2.h"
-#include "monitor_wrap.h"
+#include "kex.h"
 
-static u_char *
+u_char *
 kex_dh_hash(
     char *client_version_string,
     char *server_version_string,
@@ -86,222 +79,3 @@ kex_dh_hash(
 #endif
         return digest;
 }
-
-/* client */
-
-static void
-kexdh_client(Kex *kex)
-{
-        BIGNUM *dh_server_pub = NULL, *shared_secret = NULL;
-        DH *dh;
-        Key *server_host_key;
-        u_char *server_host_key_blob = NULL, *signature = NULL;
-        u_char *kbuf, *hash;
-        u_int klen, kout, slen, sbloblen;
-
-        /* generate and send 'e', client DH public key */
-        dh = dh_new_group1();
-        dh_gen_key(dh, kex->we_need * 8);
-        packet_start(SSH2_MSG_KEXDH_INIT);
-        packet_put_bignum2(dh->pub_key);
-        packet_send();
-
-        debug("sending SSH2_MSG_KEXDH_INIT");
-#ifdef DEBUG_KEXDH
-        DHparams_print_fp(stderr, dh);
-        fprintf(stderr, "pub= ");
-        BN_print_fp(stderr, dh->pub_key);
-        fprintf(stderr, "\n");
-#endif
-
-        debug("expecting SSH2_MSG_KEXDH_REPLY");
-        packet_read_expect(SSH2_MSG_KEXDH_REPLY);
-
-        /* key, cert */
-        server_host_key_blob = packet_get_string(&sbloblen);
-        server_host_key = key_from_blob(server_host_key_blob, sbloblen);
-        if (server_host_key == NULL)
-                fatal("cannot decode server_host_key_blob");
-        if (server_host_key->type != kex->hostkey_type)
-                fatal("type mismatch for decoded server_host_key_blob");
-        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 */
-        if ((dh_server_pub = BN_new()) == NULL)
-                fatal("dh_server_pub == NULL");
-        packet_get_bignum2(dh_server_pub);
-
-#ifdef DEBUG_KEXDH
-        fprintf(stderr, "dh_server_pub= ");
-        BN_print_fp(stderr, dh_server_pub);
-        fprintf(stderr, "\n");
-        debug("bits %d", BN_num_bits(dh_server_pub));
-#endif
-
-        /* signed H */
-        signature = packet_get_string(&slen);
-        packet_check_eom();
-
-        if (!dh_pub_is_valid(dh, dh_server_pub))
-                packet_disconnect("bad server public DH value");
-
-        klen = DH_size(dh);
-        kbuf = xmalloc(klen);
-        kout = DH_compute_key(kbuf, dh_server_pub, dh);
-#ifdef DEBUG_KEXDH
-        dump_digest("shared secret", kbuf, kout);
-#endif
-        if ((shared_secret = BN_new()) == NULL)
-                fatal("kexdh_client: BN_new failed");
-        BN_bin2bn(kbuf, kout, shared_secret);
-        memset(kbuf, 0, klen);
-        xfree(kbuf);
-
-        /* calc and verify H */
-        hash = kex_dh_hash(
-            kex->client_version_string,
-            kex->server_version_string,
-            buffer_ptr(&kex->my), buffer_len(&kex->my),
-            buffer_ptr(&kex->peer), buffer_len(&kex->peer),
-            server_host_key_blob, sbloblen,
-            dh->pub_key,
-            dh_server_pub,
-            shared_secret
-        );
-        xfree(server_host_key_blob);
-        BN_clear_free(dh_server_pub);
-        DH_free(dh);
-
-        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);
-
-        /* save session id */
-        if (kex->session_id == NULL) {
-                kex->session_id_len = 20;
-                kex->session_id = xmalloc(kex->session_id_len);
-                memcpy(kex->session_id, hash, kex->session_id_len);
-        }
-
-        kex_derive_keys(kex, hash, shared_secret);
-        BN_clear_free(shared_secret);
-        kex_finish(kex);
-}
-
-/* server */
-
-static void
-kexdh_server(Kex *kex)
-{
-        BIGNUM *shared_secret = NULL, *dh_client_pub = NULL;
-        DH *dh;
-        Key *server_host_key;
-        u_char *kbuf, *hash, *signature = NULL, *server_host_key_blob = NULL;
-        u_int sbloblen, klen, kout;
-        u_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(SSH2_MSG_KEXDH_INIT);
-
-        if (kex->load_host_key == NULL)
-                fatal("Cannot load hostkey");
-        server_host_key = kex->load_host_key(kex->hostkey_type);
-        if (server_host_key == NULL)
-                fatal("Unsupported hostkey type %d", kex->hostkey_type);
-
-        /* key, cert */
-        if ((dh_client_pub = BN_new()) == NULL)
-                fatal("dh_client_pub == NULL");
-        packet_get_bignum2(dh_client_pub);
-        packet_check_eom();
-
-#ifdef DEBUG_KEXDH
-        fprintf(stderr, "dh_client_pub= ");
-        BN_print_fp(stderr, dh_client_pub);
-        fprintf(stderr, "\n");
-        debug("bits %d", BN_num_bits(dh_client_pub));
-#endif
-
-#ifdef DEBUG_KEXDH
-        DHparams_print_fp(stderr, dh);
-        fprintf(stderr, "pub= ");
-        BN_print_fp(stderr, dh->pub_key);
-        fprintf(stderr, "\n");
-#endif
-        if (!dh_pub_is_valid(dh, dh_client_pub))
-                packet_disconnect("bad client public DH value");
-
-        klen = DH_size(dh);
-        kbuf = xmalloc(klen);
-        kout = DH_compute_key(kbuf, dh_client_pub, dh);
-#ifdef DEBUG_KEXDH
-        dump_digest("shared secret", kbuf, kout);
-#endif
-        if ((shared_secret = BN_new()) == NULL)
-                fatal("kexdh_server: BN_new failed");
-        BN_bin2bn(kbuf, kout, shared_secret);
-        memset(kbuf, 0, klen);
-        xfree(kbuf);
-
-        key_to_blob(server_host_key, &server_host_key_blob, &sbloblen);
-
-        /* calc H */
-        hash = 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),
-            server_host_key_blob, sbloblen,
-            dh_client_pub,
-            dh->pub_key,
-            shared_secret
-        );
-        BN_clear_free(dh_client_pub);
-
-        /* save session id := H */
-        /* XXX hashlen depends on KEX */
-        if (kex->session_id == NULL) {
-                kex->session_id_len = 20;
-                kex->session_id = xmalloc(kex->session_id_len);
-                memcpy(kex->session_id, hash, kex->session_id_len);
-        }
-
-        /* sign H */
-        /* XXX hashlen depends on KEX */
-        PRIVSEP(key_sign(server_host_key, &signature, &slen, hash, 20));
-
-        /* 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();
-
-        xfree(signature);
-        xfree(server_host_key_blob);
-        /* have keys, free DH */
-        DH_free(dh);
-
-        kex_derive_keys(kex, hash, shared_secret);
-        BN_clear_free(shared_secret);
-        kex_finish(kex);
-}
-
-void
-kexdh(Kex *kex)
-{
-        if (kex->server)
-                kexdh_server(kex);
-        else
-                kexdh_client(kex);
-}