- OpenBSD CVS updates:

  - markus@cvs.openbsd.org
    [session.c]
    make x11-fwd work w/ localhost (xauth add host/unix:11)
    [cipher.c compat.c readconf.c servconf.c]
    check strtok() != NULL; ok niels@
    [key.c]
    fix key_read() for uuencoded keys w/o '='
    [serverloop.c]
    group ssh1 vs. ssh2 in serverloop
    [kex.c kex.h myproposal.h sshconnect2.c sshd.c]
    split kexinit/kexdh, factor out common code
    [readconf.c ssh.1 ssh.c]
    forwardagent defaults to no, add ssh -A
  - theo@cvs.openbsd.org
    [session.c]
    just some line shortening

1 files changed, 57 insertions, 80 deletions

diff --git a/sshconnect2.c b/sshconnect2.c
index 99ffb2c47..0abcf89a0 100644
--- a/sshconnect2.c
+++ b/sshconnect2.c
@@ -28,7 +28,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: sshconnect2.c,v 1.10 2000/05/08 17:42:25 markus Exp $");
+RCSID("$OpenBSD: sshconnect2.c,v 1.11 2000/05/25 20:45:20 markus Exp $");
 
 #include <openssl/bn.h>
 #include <openssl/rsa.h>
@@ -68,16 +68,12 @@ unsigned char *session_id2 = NULL;
 int session_id2_len = 0;
 
 void
-ssh_kex2(char *host, struct sockaddr *hostaddr)
+ssh_kex_dh(Kex *kex, char *host, struct sockaddr *hostaddr,
+    Buffer *client_kexinit, Buffer *server_kexinit)
 {
-        Kex *kex;
-        char *cprop[PROPOSAL_MAX];
-        char *sprop[PROPOSAL_MAX];
-        Buffer *client_kexinit;
-        Buffer *server_kexinit;
-        int payload_len, dlen;
+        int i;
+        int plen, dlen;
         unsigned int klen, kout;
-        char *ptr;
         char *signature = NULL;
         unsigned int slen;
         char *server_host_key_blob = NULL;
@@ -86,72 +82,10 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
         DH *dh;
         BIGNUM *dh_server_pub = 0;
         BIGNUM *shared_secret = 0;
-        int i;
         unsigned char *kbuf;
         unsigned char *hash;
 
-/* KEXINIT */
-
-        debug("Sending KEX init.");
-        if (options.ciphers != NULL) {
-                myproposal[PROPOSAL_ENC_ALGS_CTOS] =
-                myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers;
-        } else if (options.cipher == SSH_CIPHER_3DES) {
-                myproposal[PROPOSAL_ENC_ALGS_CTOS] =
-                myproposal[PROPOSAL_ENC_ALGS_STOC] =
-                    cipher_name(SSH_CIPHER_3DES_CBC);
-        } else if (options.cipher == SSH_CIPHER_BLOWFISH) {
-                myproposal[PROPOSAL_ENC_ALGS_CTOS] =
-                myproposal[PROPOSAL_ENC_ALGS_STOC] =
-                    cipher_name(SSH_CIPHER_BLOWFISH_CBC);
-        }
-        if (options.compression) {
-                myproposal[PROPOSAL_COMP_ALGS_CTOS] = "zlib";
-                myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib";
-        } else {
-                myproposal[PROPOSAL_COMP_ALGS_CTOS] = "none";
-                myproposal[PROPOSAL_COMP_ALGS_STOC] = "none";
-        }
-        for (i = 0; i < PROPOSAL_MAX; i++)
-                cprop[i] = xstrdup(myproposal[i]);
-
-        client_kexinit = kex_init(cprop);
-        packet_start(SSH2_MSG_KEXINIT);
-        packet_put_raw(buffer_ptr(client_kexinit), buffer_len(client_kexinit)); 
-        packet_send();
-        packet_write_wait();
-
-        debug("done");
-
-        packet_read_expect(&payload_len, SSH2_MSG_KEXINIT);
-
-        /* save payload for session_id */
-        server_kexinit = xmalloc(sizeof(*server_kexinit));
-        buffer_init(server_kexinit);
-        ptr = packet_get_raw(&payload_len);
-        buffer_append(server_kexinit, ptr, payload_len);
-
-        /* skip cookie */
-        for (i = 0; i < 16; i++)
-                (void) packet_get_char();
-        /* kex init proposal strings */
-        for (i = 0; i < PROPOSAL_MAX; i++) {
-                sprop[i] = packet_get_string(NULL);
-                debug("got kexinit string: %s", sprop[i]);
-        }
-        i = (int) packet_get_char();
-        debug("first kex follow == %d", i);
-        i = packet_get_int();
-        debug("reserved == %d", i);
-        packet_done();
-
-        debug("done read kexinit");
-        kex = kex_choose_conf(cprop, sprop, 0);
-
-/* KEXDH */
-
         debug("Sending SSH2_MSG_KEXDH_INIT.");
-
         /* generate and send 'e', client DH public key */
         dh = dh_new_group1();
         packet_start(SSH2_MSG_KEXDH_INIT);
@@ -172,7 +106,7 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
 
         debug("Wait SSH2_MSG_KEXDH_REPLY.");
 
-        packet_read_expect(&payload_len, SSH2_MSG_KEXDH_REPLY);
+        packet_read_expect(&plen, SSH2_MSG_KEXDH_REPLY);
 
         debug("Got SSH2_MSG_KEXDH_REPLY.");
 
@@ -233,10 +167,7 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
             shared_secret
         );
         xfree(server_host_key_blob);
-        buffer_free(client_kexinit);
-        buffer_free(server_kexinit);
-        xfree(client_kexinit);
-        xfree(server_kexinit);
+        DH_free(dh);
 #ifdef DEBUG_KEXDH
         fprintf(stderr, "hash == ");
         for (i = 0; i< 20; i++)
@@ -250,16 +181,61 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
         kex_derive_keys(kex, hash, shared_secret);
         packet_set_kex(kex);
 
-        /* have keys, free DH */
-        DH_free(dh);
-
         /* save session id */
         session_id2_len = 20;
         session_id2 = xmalloc(session_id2_len);
         memcpy(session_id2, hash, session_id2_len);
+}
+
+void
+ssh_kex2(char *host, struct sockaddr *hostaddr)
+{
+        int i, plen;
+        Kex *kex;
+        Buffer *client_kexinit, *server_kexinit;
+        char *sprop[PROPOSAL_MAX];
+
+        if (options.ciphers != NULL) {
+                myproposal[PROPOSAL_ENC_ALGS_CTOS] =
+                myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers;
+        } else if (options.cipher == SSH_CIPHER_3DES) {
+                myproposal[PROPOSAL_ENC_ALGS_CTOS] =
+                myproposal[PROPOSAL_ENC_ALGS_STOC] =
+                    (char *) cipher_name(SSH_CIPHER_3DES_CBC);
+        } else if (options.cipher == SSH_CIPHER_BLOWFISH) {
+                myproposal[PROPOSAL_ENC_ALGS_CTOS] =
+                myproposal[PROPOSAL_ENC_ALGS_STOC] =
+                    (char *) cipher_name(SSH_CIPHER_BLOWFISH_CBC);
+        }
+        if (options.compression) {
+                myproposal[PROPOSAL_COMP_ALGS_CTOS] = "zlib";
+                myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib";
+        } else {
+                myproposal[PROPOSAL_COMP_ALGS_CTOS] = "none";
+                myproposal[PROPOSAL_COMP_ALGS_STOC] = "none";
+        }
+
+        /* buffers with raw kexinit messages */
+        server_kexinit = xmalloc(sizeof(*server_kexinit));
+        buffer_init(server_kexinit);
+        client_kexinit = kex_init(myproposal);
+
+        /* algorithm negotiation */
+        kex_exchange_kexinit(client_kexinit, server_kexinit, sprop);
+        kex = kex_choose_conf(myproposal, sprop, 0);
+        for (i = 0; i < PROPOSAL_MAX; i++)
+                xfree(sprop[i]);
+
+        /* server authentication and session key agreement */
+        ssh_kex_dh(kex, host, hostaddr, client_kexinit, server_kexinit);
+
+        buffer_free(client_kexinit);
+        buffer_free(server_kexinit);
+        xfree(client_kexinit);
+        xfree(server_kexinit);
 
         debug("Wait SSH2_MSG_NEWKEYS.");
-        packet_read_expect(&payload_len, SSH2_MSG_NEWKEYS);
+        packet_read_expect(&plen, SSH2_MSG_NEWKEYS);
         packet_done();
         debug("GOT SSH2_MSG_NEWKEYS.");
 
@@ -278,6 +254,7 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
 #endif
         debug("done: KEX2.");
 }
+
 /*
  * Authenticate user
  */