]> andersk Git - openssh.git/blobdiff - sshconnect2.c
- markus@cvs.openbsd.org 2001/04/11 10:59:01
[openssh.git] / sshconnect2.c
index 046d746a4ec14429a37309378fa55d0b4e923d82..da5b71478470657e28be3cba67702774602c6114 100644 (file)
@@ -23,7 +23,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: sshconnect2.c,v 1.54 2001/03/12 22:02:02 markus Exp $");
+RCSID("$OpenBSD: sshconnect2.c,v 1.67 2001/04/05 10:42:56 markus Exp $");
 
 #include <openssl/bn.h>
 #include <openssl/md5.h>
@@ -46,15 +46,13 @@ RCSID("$OpenBSD: sshconnect2.c,v 1.54 2001/03/12 22:02:02 markus Exp $");
 #include "sshconnect.h"
 #include "authfile.h"
 #include "cli.h"
-#include "dispatch.h"
+#include "dh.h"
 #include "authfd.h"
 #include "log.h"
 #include "readconf.h"
 #include "readpass.h"
 #include "match.h"
-
-void ssh_dh1_client(Kex *, char *, struct sockaddr *, Buffer *, Buffer *);
-void ssh_dhgex_client(Kex *, char *, struct sockaddr *, Buffer *, Buffer *);
+#include "dispatch.h"
 
 /* import */
 extern char *client_version_string;
@@ -68,13 +66,26 @@ extern Options options;
 u_char *session_id2 = NULL;
 int session_id2_len = 0;
 
+char *xxx_host;
+struct sockaddr *xxx_hostaddr;
+
+Kex *xxx_kex = NULL;
+
+int
+check_host_key_callback(Key *hostkey)
+{
+       check_host_key(xxx_host, xxx_hostaddr, hostkey,
+           options.user_hostfile2, options.system_hostfile2);
+       return 0;
+}
+
 void
 ssh_kex2(char *host, struct sockaddr *hostaddr)
 {
-       int i, plen;
        Kex *kex;
-       Buffer *client_kexinit, *server_kexinit;
-       char *sprop[PROPOSAL_MAX];
+
+       xxx_host = host;
+       xxx_hostaddr = hostaddr;
 
        if (options.ciphers == (char *)-1) {
                log("No valid ciphers for protocol version 2 given, using defaults.");
@@ -84,6 +95,10 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
                myproposal[PROPOSAL_ENC_ALGS_CTOS] =
                myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers;
        }
+       myproposal[PROPOSAL_ENC_ALGS_CTOS] =
+           compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_CTOS]);
+       myproposal[PROPOSAL_ENC_ALGS_STOC] =
+           compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_STOC]);
        if (options.compression) {
                myproposal[PROPOSAL_COMP_ALGS_CTOS] =
                myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib";
@@ -96,46 +111,18 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
                myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
        }
 
-       /* 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 */
-       switch(kex->kex_type) {
-       case DH_GRP1_SHA1:
-               ssh_dh1_client(kex, host, hostaddr,
-                              client_kexinit, server_kexinit);
-               break;
-       case DH_GEX_SHA1:
-               ssh_dhgex_client(kex, host, hostaddr, client_kexinit,
-                                server_kexinit);
-               break;
-       default:
-               fatal("Unsupported key exchange %d", kex->kex_type);
-       }
+       /* start key exchange */
+       kex = kex_setup(myproposal);
+       kex->client_version_string=client_version_string;
+       kex->server_version_string=server_version_string;
+       kex->check_host_key=&check_host_key_callback;
 
-       buffer_free(client_kexinit);
-       buffer_free(server_kexinit);
-       xfree(client_kexinit);
-       xfree(server_kexinit);
+       xxx_kex = kex;
 
-       debug("Wait SSH2_MSG_NEWKEYS.");
-       packet_read_expect(&plen, SSH2_MSG_NEWKEYS);
-       packet_done();
-       debug("GOT SSH2_MSG_NEWKEYS.");
+       dispatch_run(DISPATCH_BLOCK, &kex->done, kex);
 
-       debug("send SSH2_MSG_NEWKEYS.");
-       packet_start(SSH2_MSG_NEWKEYS);
-       packet_send();
-       packet_write_wait();
-       debug("done: send SSH2_MSG_NEWKEYS.");
+       session_id2 = kex->session_id;
+       session_id2_len = kex->session_id_len;
 
 #ifdef DEBUG_KEXDH
        /* send 1st encrypted/maced/compressed message */
@@ -144,310 +131,7 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
        packet_send();
        packet_write_wait();
 #endif
-       debug("done: KEX2.");
-}
-
-/* diffie-hellman-group1-sha1 */
-
-void
-ssh_dh1_client(Kex *kex, char *host, struct sockaddr *hostaddr,
-              Buffer *client_kexinit, Buffer *server_kexinit)
-{
-#ifdef DEBUG_KEXDH
-       int i;
-#endif
-       int plen, dlen;
-       u_int klen, kout;
-       char *signature = NULL;
-       u_int slen;
-       char *server_host_key_blob = NULL;
-       Key *server_host_key;
-       u_int sbloblen;
-       DH *dh;
-       BIGNUM *dh_server_pub = 0;
-       BIGNUM *shared_secret = 0;
-       u_char *kbuf;
-       u_char *hash;
-
-       debug("Sending SSH2_MSG_KEXDH_INIT.");
-       /* 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();
-       packet_write_wait();
-
-#ifdef DEBUG_KEXDH
-       fprintf(stderr, "\np= ");
-       BN_print_fp(stderr, dh->p);
-       fprintf(stderr, "\ng= ");
-       BN_print_fp(stderr, dh->g);
-       fprintf(stderr, "\npub= ");
-       BN_print_fp(stderr, dh->pub_key);
-       fprintf(stderr, "\n");
-       DHparams_print_fp(stderr, dh);
-#endif
-
-       debug("Wait SSH2_MSG_KEXDH_REPLY.");
-
-       packet_read_expect(&plen, SSH2_MSG_KEXDH_REPLY);
-
-       debug("Got 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");
-
-       check_host_key(host, hostaddr, server_host_key,
-                      options.user_hostfile2, options.system_hostfile2);
-
-       /* DH paramter f, server public DH key */
-       dh_server_pub = BN_new();
-       if (dh_server_pub == NULL)
-               fatal("dh_server_pub == NULL");
-       packet_get_bignum2(dh_server_pub, &dlen);
-
-#ifdef DEBUG_KEXDH
-       fprintf(stderr, "\ndh_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_done();
-
-       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
-       debug("shared secret: len %d/%d", klen, kout);
-       fprintf(stderr, "shared secret == ");
-       for (i = 0; i< kout; i++)
-               fprintf(stderr, "%02x", (kbuf[i])&0xff);
-       fprintf(stderr, "\n");
-#endif
-       shared_secret = BN_new();
-
-       BN_bin2bn(kbuf, kout, shared_secret);
-       memset(kbuf, 0, klen);
-       xfree(kbuf);
-
-       /* calc and verify H */
-       hash = kex_hash(
-           client_version_string,
-           server_version_string,
-           buffer_ptr(client_kexinit), buffer_len(client_kexinit),
-           buffer_ptr(server_kexinit), buffer_len(server_kexinit),
-           server_host_key_blob, sbloblen,
-           dh->pub_key,
-           dh_server_pub,
-           shared_secret
-       );
-       xfree(server_host_key_blob);
-       DH_free(dh);
-       BN_free(dh_server_pub);
-#ifdef DEBUG_KEXDH
-       fprintf(stderr, "hash == ");
-       for (i = 0; i< 20; i++)
-               fprintf(stderr, "%02x", (hash[i])&0xff);
-       fprintf(stderr, "\n");
-#endif
-       if (key_verify(server_host_key, (u_char *)signature, slen, hash, 20) != 1)
-               fatal("key_verify failed for server_host_key");
-       key_free(server_host_key);
-       xfree(signature);
-
-       kex_derive_keys(kex, hash, shared_secret);
-       BN_clear_free(shared_secret);
-       packet_set_kex(kex);
-
-       /* save session id */
-       session_id2_len = 20;
-       session_id2 = xmalloc(session_id2_len);
-       memcpy(session_id2, hash, session_id2_len);
-}
-
-/* diffie-hellman-group-exchange-sha1 */
-
-/*
- * Estimates the group order for a Diffie-Hellman group that has an
- * attack complexity approximately the same as O(2**bits).  Estimate
- * with:  O(exp(1.9223 * (ln q)^(1/3) (ln ln q)^(2/3)))
- */
-
-int
-dh_estimate(int bits)
-{
-
-       if (bits < 64)
-               return (512);   /* O(2**63) */
-       if (bits < 128)
-               return (1024);  /* O(2**86) */
-       if (bits < 192)
-               return (2048);  /* O(2**116) */
-       return (4096);          /* O(2**156) */
-}
-
-void
-ssh_dhgex_client(Kex *kex, char *host, struct sockaddr *hostaddr,
-                Buffer *client_kexinit, Buffer *server_kexinit)
-{
-#ifdef DEBUG_KEXDH
-       int i;
-#endif
-       int plen, dlen;
-       u_int klen, kout;
-       char *signature = NULL;
-       u_int slen, nbits;
-       char *server_host_key_blob = NULL;
-       Key *server_host_key;
-       u_int sbloblen;
-       DH *dh;
-       BIGNUM *dh_server_pub = 0;
-       BIGNUM *shared_secret = 0;
-       BIGNUM *p = 0, *g = 0;
-       u_char *kbuf;
-       u_char *hash;
-
-       nbits = dh_estimate(kex->we_need * 8);
-
-       debug("Sending SSH2_MSG_KEX_DH_GEX_REQUEST.");
-       packet_start(SSH2_MSG_KEX_DH_GEX_REQUEST);
-       packet_put_int(nbits);
-       packet_send();
-       packet_write_wait();
-
-#ifdef DEBUG_KEXDH
-       fprintf(stderr, "\nnbits = %d", nbits);
-#endif
-
-       debug("Wait SSH2_MSG_KEX_DH_GEX_GROUP.");
-
-       packet_read_expect(&plen, SSH2_MSG_KEX_DH_GEX_GROUP);
-
-       debug("Got SSH2_MSG_KEX_DH_GEX_GROUP.");
-
-       if ((p = BN_new()) == NULL)
-               fatal("BN_new");
-       packet_get_bignum2(p, &dlen);
-       if ((g = BN_new()) == NULL)
-               fatal("BN_new");
-       packet_get_bignum2(g, &dlen);
-       dh = dh_new_group(g, p);
-
-       dh_gen_key(dh, kex->we_need * 8);
-
-#ifdef DEBUG_KEXDH
-       fprintf(stderr, "\np= ");
-       BN_print_fp(stderr, dh->p);
-       fprintf(stderr, "\ng= ");
-       BN_print_fp(stderr, dh->g);
-       fprintf(stderr, "\npub= ");
-       BN_print_fp(stderr, dh->pub_key);
-       fprintf(stderr, "\n");
-       DHparams_print_fp(stderr, dh);
-#endif
-
-       debug("Sending SSH2_MSG_KEX_DH_GEX_INIT.");
-       /* generate and send 'e', client DH public key */
-       packet_start(SSH2_MSG_KEX_DH_GEX_INIT);
-       packet_put_bignum2(dh->pub_key);
-       packet_send();
-       packet_write_wait();
-
-       debug("Wait SSH2_MSG_KEX_DH_GEX_REPLY.");
-
-       packet_read_expect(&plen, SSH2_MSG_KEX_DH_GEX_REPLY);
-
-       debug("Got 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");
-
-       check_host_key(host, hostaddr, server_host_key,
-                      options.user_hostfile2, options.system_hostfile2);
-
-       /* DH paramter f, server public DH key */
-       dh_server_pub = BN_new();
-       if (dh_server_pub == NULL)
-               fatal("dh_server_pub == NULL");
-       packet_get_bignum2(dh_server_pub, &dlen);
-
-#ifdef DEBUG_KEXDH
-       fprintf(stderr, "\ndh_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_done();
-
-       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
-       debug("shared secret: len %d/%d", klen, kout);
-       fprintf(stderr, "shared secret == ");
-       for (i = 0; i< kout; i++)
-               fprintf(stderr, "%02x", (kbuf[i])&0xff);
-       fprintf(stderr, "\n");
-#endif
-       shared_secret = BN_new();
-
-       BN_bin2bn(kbuf, kout, shared_secret);
-       memset(kbuf, 0, klen);
-       xfree(kbuf);
-
-       /* calc and verify H */
-       hash = kex_hash_gex(
-           client_version_string,
-           server_version_string,
-           buffer_ptr(client_kexinit), buffer_len(client_kexinit),
-           buffer_ptr(server_kexinit), buffer_len(server_kexinit),
-           server_host_key_blob, sbloblen,
-           nbits, dh->p, dh->g,
-           dh->pub_key,
-           dh_server_pub,
-           shared_secret
-       );
-       xfree(server_host_key_blob);
-       DH_free(dh);
-       BN_free(dh_server_pub);
-#ifdef DEBUG_KEXDH
-       fprintf(stderr, "hash == ");
-       for (i = 0; i< 20; i++)
-               fprintf(stderr, "%02x", (hash[i])&0xff);
-       fprintf(stderr, "\n");
-#endif
-       if (key_verify(server_host_key, (u_char *)signature, slen, hash, 20) != 1)
-               fatal("key_verify failed for server_host_key");
-       key_free(server_host_key);
-       xfree(signature);
-
-       kex_derive_keys(kex, hash, shared_secret);
-       BN_clear_free(shared_secret);
-       packet_set_kex(kex);
-
-       /* save session id */
-       session_id2_len = 20;
-       session_id2 = xmalloc(session_id2_len);
-       memcpy(session_id2, hash, session_id2_len);
+       debug("done: ssh_kex2.");
 }
 
 /*
@@ -898,26 +582,24 @@ load_identity_file(char *filename)
 {
        Key *private;
        char prompt[300], *passphrase;
-       int success = 0, quit, i;
+       int quit, i;
        struct stat st;
 
        if (stat(filename, &st) < 0) {
                debug3("no such identity: %s", filename);
                return NULL;
        }
-       private = key_new(KEY_UNSPEC);
-       if (!load_private_key(filename, "", private, NULL)) {
-               if (options.batch_mode) {
-                       key_free(private);
+       private = key_load_private_type(KEY_UNSPEC, filename, "", NULL);
+       if (private == NULL) {
+               if (options.batch_mode)
                        return NULL;
-               }
                snprintf(prompt, sizeof prompt,
                     "Enter passphrase for key '%.100s': ", filename);
                for (i = 0; i < options.number_of_password_prompts; i++) {
                        passphrase = read_passphrase(prompt, 0);
                        if (strcmp(passphrase, "") != 0) {
-                               success = load_private_key(filename,
-                                   passphrase, private, NULL);
+                               private = key_load_private_type(KEY_UNSPEC, filename,
+                                   passphrase, NULL);
                                quit = 0;
                        } else {
                                debug2("no passphrase given, try next key");
@@ -925,14 +607,10 @@ load_identity_file(char *filename)
                        }
                        memset(passphrase, 0, strlen(passphrase));
                        xfree(passphrase);
-                       if (success || quit)
+                       if (private != NULL || quit)
                                break;
                        debug2("bad passphrase given, try again...");
                }
-               if (!success) {
-                       key_free(private);
-                       return NULL;
-               }
        }
        return private;
 }
@@ -964,7 +642,7 @@ int agent_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, int *lenp,
 int key_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, int *lenp,
     u_char *data, int datalen)
 {
-        return key_sign(key, sigp, lenp, data, datalen);
+       return key_sign(key, sigp, lenp, data, datalen);
 }
 
 int
@@ -1147,7 +825,7 @@ static char *preferred = NULL;
 /*
  * Given the authentication method list sent by the server, return the
  * next method we should try.  If the server initially sends a nil list,
- * use a built-in default list. 
+ * use a built-in default list.
  */
 Authmethod *
 authmethod_get(char *authlist)
This page took 0.104292 seconds and 4 git commands to generate.