- OpenBSD CVS updates:

[openssh.git] / kex.c

diff --git a/kex.c b/kex.c
index 9c41b5123e1d2c8b1e7e71a5a3ff5525d59caabd..3a925f94e64826641f7715784155db376036a8ec 100644 (file)
--- a/kex.c
+++ b/kex.c
@@ -35,6 +35,7 @@ RCSID("$Id$");
 #include "xmalloc.h"
 #include "buffer.h"
 #include "bufaux.h"
+#include "packet.h"
 #include "cipher.h"
 #include "compat.h"
 
@@ -49,15 +50,17 @@ RCSID("$Id$");
 
 #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
@@ -133,12 +180,6 @@ dh_new_group1()
        return dh;
 }
 
-void
-bignum_print(BIGNUM *b)
-{
-       BN_print_fp(stderr,b);
-}
-
 void
 dump_digest(unsigned char *digest, int len)
 {
@@ -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;
 }