- 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, 70 insertions, 26 deletions

diff --git a/kex.c b/kex.c
index 221e03041..199e04264 100644
--- a/kex.c
+++ b/kex.c
@@ -28,13 +28,14 @@
  */
 
 #include "includes.h"
-RCSID("$Id: kex.c,v 1.8 2000/05/09 01:03:01 damien Exp $");
+RCSID("$Id: kex.c,v 1.9 2000/05/30 03:44:53 damien Exp $");
 
 #include "ssh.h"
 #include "ssh2.h"
 #include "xmalloc.h"
 #include "buffer.h"
 #include "bufaux.h"
+#include "packet.h"
 #include "cipher.h"
 #include "compat.h"
 
@@ -49,15 +50,17 @@ RCSID("$Id: kex.c,v 1.8 2000/05/09 01:03:01 damien Exp $");
 
 #include "kex.h"
 
+#define KEX_COOKIE_LEN  16
+
 Buffer *
 kex_init(char *myproposal[PROPOSAL_MAX])
 {
-        char c = 0;
-        unsigned char cookie[16];
+        int first_kex_packet_follows = 0;
+        unsigned char cookie[KEX_COOKIE_LEN];
         u_int32_t rand = 0;
         int i;
         Buffer *ki = xmalloc(sizeof(*ki));
-        for (i = 0; i < 16; i++) {
+        for (i = 0; i < KEX_COOKIE_LEN; i++) {
                 if (i % 4 == 0)
                         rand = arc4random();
                 cookie[i] = rand & 0xff;
@@ -67,11 +70,55 @@ kex_init(char *myproposal[PROPOSAL_MAX])
         buffer_append(ki, (char *)cookie, sizeof cookie);
         for (i = 0; i < PROPOSAL_MAX; i++)
                 buffer_put_cstring(ki, myproposal[i]);
-        buffer_append(ki, &c, 1); /* boolean   first_kex_packet_follows */
-        buffer_put_int(ki, 0);    /* uint32    0 (reserved for future extension) */
+        buffer_put_char(ki, first_kex_packet_follows);
+        buffer_put_int(ki, 0);                          /* uint32 reserved */
         return ki;
 }
 
+/* send kexinit, parse and save reply */
+void
+kex_exchange_kexinit(
+    Buffer *my_kexinit, Buffer *peer_kexint,
+    char *peer_proposal[PROPOSAL_MAX])
+{
+        int i;
+        char *ptr;
+        int plen;
+
+        debug("send KEXINIT");
+        packet_start(SSH2_MSG_KEXINIT);
+        packet_put_raw(buffer_ptr(my_kexinit), buffer_len(my_kexinit)); 
+        packet_send();
+        packet_write_wait();
+        debug("done");
+
+        /*
+         * read and save raw KEXINIT payload in buffer. this is used during
+         * computation of the session_id and the session keys.
+         */
+        debug("wait KEXINIT");
+        packet_read_expect(&plen, SSH2_MSG_KEXINIT);
+        ptr = packet_get_raw(&plen);
+        buffer_append(peer_kexint, ptr, plen);
+
+        /* parse packet and save algorithm proposal */
+        /* skip cookie */
+        for (i = 0; i < KEX_COOKIE_LEN; i++)
+                packet_get_char();
+        /* extract kex init proposal strings */
+        for (i = 0; i < PROPOSAL_MAX; i++) {
+                peer_proposal[i] = packet_get_string(NULL);
+                debug("got kexinit: %s", peer_proposal[i]);
+        }
+        /* first kex follow / reserved */
+        i = packet_get_char();
+        debug("first kex follow: %d ", i);
+        i = packet_get_int();
+        debug("reserved: %d ", i);
+        packet_done();
+        debug("done");
+}
+
 /* diffie-hellman-group1-sha1 */
 
 int
@@ -134,12 +181,6 @@ dh_new_group1()
 }
 
 void
-bignum_print(BIGNUM *b)
-{
-        BN_print_fp(stderr,b);
-}
-
-void
 dump_digest(unsigned char *digest, int len)
 {
         int i;
@@ -246,10 +287,13 @@ char *
 get_match(char *client, char *server)
 {
         char *sproposals[MAX_PROP];
-        char *p;
+        char *c, *s, *p, *ret;
         int i, j, nproposals;
 
-        for ((p = strtok(server, SEP)), i=0; p; (p = strtok(NULL, SEP)), i++) {
+        c = xstrdup(client);
+        s = xstrdup(server);
+
+        for ((p = strtok(s, SEP)), i=0; p; (p = strtok(NULL, SEP)), i++) {
                 if (i < MAX_PROP)
                         sproposals[i] = p;
                 else
@@ -257,11 +301,18 @@ get_match(char *client, char *server)
         }
         nproposals = i;
 
-        for ((p = strtok(client, SEP)), i=0; p; (p = strtok(NULL, SEP)), i++) {
-                for (j = 0; j < nproposals; j++)
-                        if (strcmp(p, sproposals[j]) == 0)
-                                return xstrdup(p);
+        for ((p = strtok(c, SEP)), i=0; p; (p = strtok(NULL, SEP)), i++) {
+                for (j = 0; j < nproposals; j++) {
+                        if (strcmp(p, sproposals[j]) == 0) {
+                                ret = xstrdup(p);
+                                xfree(c);
+                                xfree(s);
+                                return ret;
+                        }
+                }
         }
+        xfree(c);
+        xfree(s);
         return NULL;
 }
 void
@@ -355,7 +406,6 @@ choose_hostkeyalg(Kex *k, char *client, char *server)
 Kex *
 kex_choose_conf(char *cprop[PROPOSAL_MAX], char *sprop[PROPOSAL_MAX], int server)
 {
-        int i;
         int mode;
         int ctos;                               /* direction: if true client-to-server */
         int need;
@@ -383,10 +433,6 @@ kex_choose_conf(char *cprop[PROPOSAL_MAX], char *sprop[PROPOSAL_MAX], int server
         choose_kex(k, cprop[PROPOSAL_KEX_ALGS], sprop[PROPOSAL_KEX_ALGS]);
         choose_hostkeyalg(k, cprop[PROPOSAL_SERVER_HOST_KEY_ALGS],
             sprop[PROPOSAL_SERVER_HOST_KEY_ALGS]);
-        for (i = 0; i < PROPOSAL_MAX; i++) {
-                xfree(cprop[i]);
-                xfree(sprop[i]);
-        }
         need = 0;
         for (mode = 0; mode < MODE_MAX; mode++) {
             if (need < k->enc[mode].key_len)
@@ -396,9 +442,7 @@ kex_choose_conf(char *cprop[PROPOSAL_MAX], char *sprop[PROPOSAL_MAX], int server
             if (need < k->mac[mode].key_len)
                     need = k->mac[mode].key_len;
         }
-        /* need runden? */
-#define WE_NEED 32
-        k->we_need = WE_NEED;
+        /* XXX need runden? */
         k->we_need = need;
         return k;
 }