]> andersk Git - openssh.git/blobdiff - sshconnect2.c
- (bal) Missed msg.[ch] in merge. Required for ssh-keysign.
[openssh.git] / sshconnect2.c
index 81e1aef930725436da7682971c43efd7f1ecb09a..6950c5ee66d55866548d0d8be9868fb8e890a6ef 100644 (file)
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: sshconnect2.c,v 1.51 2001/03/08 21:42:33 markus Exp $");
-
-#include <openssl/bn.h>
-#include <openssl/md5.h>
-#include <openssl/dh.h>
-#include <openssl/hmac.h>
+RCSID("$OpenBSD: sshconnect2.c,v 1.103 2002/05/31 10:30:33 markus Exp $");
 
 #include "ssh.h"
 #include "ssh2.h"
 #include "xmalloc.h"
-#include "rsa.h"
 #include "buffer.h"
 #include "packet.h"
-#include "uidswap.h"
 #include "compat.h"
 #include "bufaux.h"
 #include "cipher.h"
 #include "kex.h"
 #include "myproposal.h"
-#include "key.h"
 #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"
-
-void ssh_dh1_client(Kex *, char *, struct sockaddr *, Buffer *, Buffer *);
-void ssh_dhgex_client(Kex *, char *, struct sockaddr *, Buffer *, Buffer *);
+#include "match.h"
+#include "dispatch.h"
+#include "canohost.h"
+#include "msg.h"
+#include "pathnames.h"
 
 /* import */
 extern char *client_version_string;
@@ -67,13 +60,26 @@ extern Options options;
 u_char *session_id2 = NULL;
 int session_id2_len = 0;
 
+char *xxx_host;
+struct sockaddr *xxx_hostaddr;
+
+Kex *xxx_kex = NULL;
+
+static int
+verify_host_key_callback(Key *hostkey)
+{
+       if (verify_host_key(xxx_host, xxx_hostaddr, hostkey) == -1)
+               fatal("Host key verification failed.");
+       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.");
@@ -83,6 +89,10 @@ 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";
@@ -94,47 +104,22 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
                myproposal[PROPOSAL_MAC_ALGS_CTOS] =
                myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
        }
+       if (options.hostkeyalgorithms != NULL)
+               myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
+                   options.hostkeyalgorithms;
 
-       /* 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->verify_host_key=&verify_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 */
@@ -143,310 +128,7 @@ 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.");
 }
 
 /*
@@ -458,19 +140,25 @@ typedef struct Authmethod Authmethod;
 
 typedef int sign_cb_fn(
     Authctxt *authctxt, Key *key,
-    u_char **sigp, int *lenp, u_char *data, int datalen);
+    u_char **sigp, u_int *lenp, u_char *data, u_int datalen);
 
 struct Authctxt {
        const char *server_user;
+       const char *local_user;
        const char *host;
        const char *service;
-       AuthenticationConnection *agent;
        Authmethod *method;
        int success;
        char *authlist;
+       /* pubkey */
        Key *last_key;
        sign_cb_fn *last_key_sign;
        int last_key_hint;
+       AuthenticationConnection *agent;
+       /* hostbased */
+       Sensitive *sensitive;
+       /* kbd-interactive */
+       int info_req_seen;
 };
 struct Authmethod {
        char    *name;          /* string to compare against server's list */
@@ -479,42 +167,46 @@ struct Authmethod {
        int     *batch_flag;    /* flag in option struct that disables method */
 };
 
-void   input_userauth_success(int type, int plen, void *ctxt);
-void   input_userauth_failure(int type, int plen, void *ctxt);
-void   input_userauth_banner(int type, int plen, void *ctxt);
-void   input_userauth_error(int type, int plen, void *ctxt);
-void   input_userauth_info_req(int type, int plen, void *ctxt);
-void   input_userauth_pk_ok(int type, int plen, void *ctxt);
+void   input_userauth_success(int, u_int32_t, void *);
+void   input_userauth_failure(int, u_int32_t, void *);
+void   input_userauth_banner(int, u_int32_t, void *);
+void   input_userauth_error(int, u_int32_t, void *);
+void   input_userauth_info_req(int, u_int32_t, void *);
+void   input_userauth_pk_ok(int, u_int32_t, void *);
+void   input_userauth_passwd_changereq(int, u_int32_t, void *);
 
-int    userauth_none(Authctxt *authctxt);
-int    userauth_pubkey(Authctxt *authctxt);
-int    userauth_passwd(Authctxt *authctxt);
-int    userauth_kbdint(Authctxt *authctxt);
+int    userauth_none(Authctxt *);
+int    userauth_pubkey(Authctxt *);
+int    userauth_passwd(Authctxt *);
+int    userauth_kbdint(Authctxt *);
+int    userauth_hostbased(Authctxt *);
 
-void   userauth(Authctxt *authctxt, char *authlist);
+void   userauth(Authctxt *, char *);
 
-int
-sign_and_send_pubkey(Authctxt *authctxt, Key *k,
-    sign_cb_fn *sign_callback);
-void   clear_auth_state(Authctxt *authctxt);
+static int sign_and_send_pubkey(Authctxt *, Key *, sign_cb_fn *);
+static void clear_auth_state(Authctxt *);
 
-void   authmethod_clear(void);
-Authmethod *authmethod_get(char *authlist);
-Authmethod *authmethod_lookup(const char *name);
+static Authmethod *authmethod_get(char *authlist);
+static Authmethod *authmethod_lookup(const char *name);
+static char *authmethods_get(void);
 
 Authmethod authmethods[] = {
+       {"hostbased",
+               userauth_hostbased,
+               &options.hostbased_authentication,
+               NULL},
        {"publickey",
                userauth_pubkey,
                &options.pubkey_authentication,
                NULL},
-       {"password",
-               userauth_passwd,
-               &options.password_authentication,
-               &options.batch_mode},
        {"keyboard-interactive",
                userauth_kbdint,
                &options.kbd_interactive_authentication,
                &options.batch_mode},
+       {"password",
+               userauth_passwd,
+               &options.password_authentication,
+               &options.batch_mode},
        {"none",
                userauth_none,
                NULL,
@@ -523,13 +215,13 @@ Authmethod authmethods[] = {
 };
 
 void
-ssh_userauth2(const char *server_user, char *host)
+ssh_userauth2(const char *local_user, const char *server_user, char *host,
+    Sensitive *sensitive)
 {
        Authctxt authctxt;
        int type;
-       int plen;
 
-       if (options.challenge_reponse_authentication)
+       if (options.challenge_response_authentication)
                options.kbd_interactive_authentication = 1;
 
        debug("send SSH2_MSG_SERVICE_REQUEST");
@@ -537,31 +229,37 @@ ssh_userauth2(const char *server_user, char *host)
        packet_put_cstring("ssh-userauth");
        packet_send();
        packet_write_wait();
-       type = packet_read(&plen);
+       type = packet_read();
        if (type != SSH2_MSG_SERVICE_ACCEPT) {
                fatal("denied SSH2_MSG_SERVICE_ACCEPT: %d", type);
        }
        if (packet_remaining() > 0) {
-               char *reply = packet_get_string(&plen);
+               char *reply = packet_get_string(NULL);
                debug("service_accept: %s", reply);
                xfree(reply);
        } else {
                debug("buggy server: service_accept w/o service");
        }
-       packet_done();
+       packet_check_eom();
        debug("got SSH2_MSG_SERVICE_ACCEPT");
 
+       if (options.preferred_authentications == NULL)
+               options.preferred_authentications = authmethods_get();
+
        /* setup authentication context */
+       memset(&authctxt, 0, sizeof(authctxt));
        authctxt.agent = ssh_get_authentication_connection();
        authctxt.server_user = server_user;
+       authctxt.local_user = local_user;
        authctxt.host = host;
        authctxt.service = "ssh-connection";            /* service name */
        authctxt.success = 0;
        authctxt.method = authmethod_lookup("none");
        authctxt.authlist = NULL;
+       authctxt.sensitive = sensitive;
+       authctxt.info_req_seen = 0;
        if (authctxt.method == NULL)
                fatal("ssh_userauth2: internal error: cannot send userauth none request");
-       authmethod_clear();
 
        /* initial userauth request */
        userauth_none(&authctxt);
@@ -602,13 +300,13 @@ userauth(Authctxt *authctxt, char *authlist)
        }
 }
 void
-input_userauth_error(int type, int plen, void *ctxt)
+input_userauth_error(int type, u_int32_t seq, void *ctxt)
 {
        fatal("input_userauth_error: bad message during authentication: "
           "type %d", type);
 }
 void
-input_userauth_banner(int type, int plen, void *ctxt)
+input_userauth_banner(int type, u_int32_t seq, void *ctxt)
 {
        char *msg, *lang;
        debug3("input_userauth_banner");
@@ -619,7 +317,7 @@ input_userauth_banner(int type, int plen, void *ctxt)
        xfree(lang);
 }
 void
-input_userauth_success(int type, int plen, void *ctxt)
+input_userauth_success(int type, u_int32_t seq, void *ctxt)
 {
        Authctxt *authctxt = ctxt;
        if (authctxt == NULL)
@@ -630,7 +328,7 @@ input_userauth_success(int type, int plen, void *ctxt)
        authctxt->success = 1;                  /* break out */
 }
 void
-input_userauth_failure(int type, int plen, void *ctxt)
+input_userauth_failure(int type, u_int32_t seq, void *ctxt)
 {
        Authctxt *authctxt = ctxt;
        char *authlist = NULL;
@@ -641,7 +339,7 @@ input_userauth_failure(int type, int plen, void *ctxt)
 
        authlist = packet_get_string(NULL);
        partial = packet_get_char();
-       packet_done();
+       packet_check_eom();
 
        if (partial != 0)
                log("Authenticated with partial success.");
@@ -651,13 +349,15 @@ input_userauth_failure(int type, int plen, void *ctxt)
        userauth(authctxt, authlist);
 }
 void
-input_userauth_pk_ok(int type, int plen, void *ctxt)
+input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt)
 {
        Authctxt *authctxt = ctxt;
        Key *key = NULL;
        Buffer b;
-       int alen, blen, pktype, sent = 0;
-       char *pkalg, *pkblob;
+       int pktype, sent = 0;
+       u_int alen, blen;
+       char *pkalg, *fp;
+       u_char *pkblob;
 
        if (authctxt == NULL)
                fatal("input_userauth_pk_ok: no authentication context");
@@ -673,7 +373,7 @@ input_userauth_pk_ok(int type, int plen, void *ctxt)
                pkalg = packet_get_string(&alen);
                pkblob = packet_get_string(&blen);
        }
-       packet_done();
+       packet_check_eom();
 
        debug("input_userauth_pk_ok: pkalg %s blen %d lastkey %p hint %d",
            pkalg, blen, authctxt->last_key, authctxt->last_key_hint);
@@ -684,7 +384,6 @@ input_userauth_pk_ok(int type, int plen, void *ctxt)
                        debug("no last key or no sign cb");
                        break;
                }
-               debug2("last_key %s", key_fingerprint(authctxt->last_key));
                if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
                        debug("unknown pkalg %s", pkalg);
                        break;
@@ -693,14 +392,22 @@ input_userauth_pk_ok(int type, int plen, void *ctxt)
                        debug("no key from blob. pkalg %s", pkalg);
                        break;
                }
-               debug2("input_userauth_pk_ok: fp %s", key_fingerprint(key));
+               if (key->type != pktype) {
+                       error("input_userauth_pk_ok: type mismatch "
+                           "for decoded key (received %d, expected %d)",
+                            key->type, pktype);
+                       break;
+               }
+               fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
+               debug2("input_userauth_pk_ok: fp %s", fp);
+               xfree(fp);
                if (!key_equal(key, authctxt->last_key)) {
                        debug("key != last_key");
                        break;
                }
                sent = sign_and_send_pubkey(authctxt, key,
                   authctxt->last_key_sign);
-       } while(0);
+       } while (0);
 
        if (key != NULL)
                key_free(key);
@@ -733,13 +440,13 @@ int
 userauth_passwd(Authctxt *authctxt)
 {
        static int attempt = 0;
-       char prompt[80];
+       char prompt[150];
        char *password;
 
        if (attempt++ >= options.number_of_password_prompts)
                return 0;
 
-       if(attempt != 1)
+       if (attempt != 1)
                error("Permission denied, please try again.");
 
        snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
@@ -753,15 +460,87 @@ userauth_passwd(Authctxt *authctxt)
        packet_put_cstring(password);
        memset(password, 0, strlen(password));
        xfree(password);
-       packet_inject_ignore(64);
+       packet_add_padding(64);
        packet_send();
+
+       dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, 
+           &input_userauth_passwd_changereq);
+
        return 1;
 }
-
+/*
+ * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
+ */
 void
+input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
+{
+       Authctxt *authctxt = ctxt;
+       char *info, *lang, *password = NULL, *retype = NULL;
+       char prompt[150];
+
+       debug2("input_userauth_passwd_changereq");
+
+       if (authctxt == NULL)
+               fatal("input_userauth_passwd_changereq: "
+                   "no authentication context");
+
+       info = packet_get_string(NULL);
+       lang = packet_get_string(NULL);
+       if (strlen(info) > 0)
+               log("%s", info);
+       xfree(info);
+       xfree(lang);
+       packet_start(SSH2_MSG_USERAUTH_REQUEST);
+       packet_put_cstring(authctxt->server_user);
+       packet_put_cstring(authctxt->service);
+       packet_put_cstring(authctxt->method->name);
+       packet_put_char(1);                     /* additional info */
+       snprintf(prompt, sizeof(prompt), 
+           "Enter %.30s@%.128s's old password: ",
+           authctxt->server_user, authctxt->host);
+       password = read_passphrase(prompt, 0);
+       packet_put_cstring(password);
+       memset(password, 0, strlen(password));
+       xfree(password);
+       password = NULL;
+       while (password == NULL) {
+               snprintf(prompt, sizeof(prompt), 
+                   "Enter %.30s@%.128s's new password: ",
+                   authctxt->server_user, authctxt->host);
+               password = read_passphrase(prompt, RP_ALLOW_EOF);
+               if (password == NULL) {
+                       /* bail out */
+                       return;
+               }
+               snprintf(prompt, sizeof(prompt), 
+                   "Retype %.30s@%.128s's new password: ",
+                   authctxt->server_user, authctxt->host);
+               retype = read_passphrase(prompt, 0);
+               if (strcmp(password, retype) != 0) {
+                       memset(password, 0, strlen(password));
+                       xfree(password);
+                       log("Mismatch; try again, EOF to quit.");
+                       password = NULL;
+               }
+               memset(retype, 0, strlen(retype));
+               xfree(retype);
+       }
+       packet_put_cstring(password);
+       memset(password, 0, strlen(password));
+       xfree(password);
+       packet_add_padding(64);
+       packet_send();
+       
+       dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, 
+           &input_userauth_passwd_changereq);
+}
+
+static void
 clear_auth_state(Authctxt *authctxt)
 {
        /* XXX clear authentication state */
+       dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, NULL);
+
        if (authctxt->last_key != NULL && authctxt->last_key_hint == -1) {
                debug3("clear_auth_state: key_free %p", authctxt->last_key);
                key_free(authctxt->last_key);
@@ -771,12 +550,12 @@ clear_auth_state(Authctxt *authctxt)
        authctxt->last_key_sign = NULL;
 }
 
-int
+static int
 sign_and_send_pubkey(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback)
 {
        Buffer b;
        u_char *blob, *signature;
-       int bloblen, slen;
+       u_int bloblen, slen;
        int skip = 0;
        int ret = -1;
        int have_sig = 1;
@@ -856,12 +635,12 @@ sign_and_send_pubkey(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback)
        return 1;
 }
 
-int
+static int
 send_pubkey_test(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback,
     int hint)
 {
        u_char *blob;
-       int bloblen, have_sig = 0;
+       u_int bloblen, have_sig = 0;
 
        debug3("send_pubkey_test");
 
@@ -889,26 +668,29 @@ send_pubkey_test(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback,
        return 1;
 }
 
-Key *
+static Key *
 load_identity_file(char *filename)
 {
        Key *private;
        char prompt[300], *passphrase;
-       int success = 0, quit, i;
+       int quit, i;
+       struct stat st;
 
-       private = key_new(KEY_UNSPEC);
-       if (!load_private_key(filename, "", private, NULL)) {
-               if (options.batch_mode) {
-                       key_free(private);
+       if (stat(filename, &st) < 0) {
+               debug3("no such identity: %s", filename);
+               return NULL;
+       }
+       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);
+                   "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");
@@ -916,21 +698,17 @@ 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;
 }
 
-int
-identity_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, int *lenp,
-    u_char *data, int datalen)
+static int
+identity_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, u_int *lenp,
+    u_char *data, u_int datalen)
 {
        Key *private;
        int idx, ret;
@@ -938,6 +716,11 @@ identity_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, int *lenp,
        idx = authctxt->last_key_hint;
        if (idx < 0)
                return -1;
+
+       /* private key is stored in external hardware */
+       if (options.identity_keys[idx]->flags & KEY_FLAG_EXT)
+               return key_sign(options.identity_keys[idx], sigp, lenp, data, datalen);
+
        private = load_identity_file(options.identity_files[idx]);
        if (private == NULL)
                return -1;
@@ -946,19 +729,21 @@ identity_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, int *lenp,
        return ret;
 }
 
-int agent_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, int *lenp,
-    u_char *data, int datalen)
+static int
+agent_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, u_int *lenp,
+    u_char *data, u_int datalen)
 {
        return ssh_agent_sign(authctxt->agent, key, sigp, lenp, data, datalen);
 }
 
-int key_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, int *lenp,
-    u_char *data, int datalen)
+static int
+key_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, u_int *lenp,
+    u_char *data, u_int datalen)
 {
-        return key_sign(key, sigp, lenp, data, datalen);
+       return key_sign(key, sigp, lenp, data, datalen);
 }
 
-int
+static int
 userauth_pubkey_agent(Authctxt *authctxt)
 {
        static int called = 0;
@@ -997,7 +782,7 @@ userauth_pubkey(Authctxt *authctxt)
        if (authctxt->agent != NULL) {
                do {
                        sent = userauth_pubkey_agent(authctxt);
-               } while(!sent && authctxt->agent->howmany > 0);
+               } while (!sent && authctxt->agent->howmany > 0);
        }
        while (!sent && idx < options.num_identity_files) {
                key = options.identity_keys[idx];
@@ -1030,6 +815,12 @@ userauth_kbdint(Authctxt *authctxt)
 
        if (attempt++ >= options.number_of_password_prompts)
                return 0;
+       /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
+       if (attempt > 1 && !authctxt->info_req_seen) {
+               debug3("userauth_kbdint: disable: no info_req_seen");
+               dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
+               return 0;
+       }
 
        debug2("userauth_kbdint");
        packet_start(SSH2_MSG_USERAUTH_REQUEST);
@@ -1049,7 +840,7 @@ userauth_kbdint(Authctxt *authctxt)
  * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
  */
 void
-input_userauth_info_req(int type, int plen, void *ctxt)
+input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
 {
        Authctxt *authctxt = ctxt;
        char *name, *inst, *lang, *prompt, *response;
@@ -1061,13 +852,15 @@ input_userauth_info_req(int type, int plen, void *ctxt)
        if (authctxt == NULL)
                fatal("input_userauth_info_req: no authentication context");
 
+       authctxt->info_req_seen = 1;
+
        name = packet_get_string(NULL);
        inst = packet_get_string(NULL);
        lang = packet_get_string(NULL);
        if (strlen(name) > 0)
-               cli_mesg(name);
+               log("%s", name);
        if (strlen(inst) > 0)
-               cli_mesg(inst);
+               log("%s", inst);
        xfree(name);
        xfree(inst);
        xfree(lang);
@@ -1082,63 +875,200 @@ input_userauth_info_req(int type, int plen, void *ctxt)
        packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
        packet_put_int(num_prompts);
 
+       debug2("input_userauth_info_req: num_prompts %d", num_prompts);
        for (i = 0; i < num_prompts; i++) {
                prompt = packet_get_string(NULL);
                echo = packet_get_char();
 
-               response = cli_prompt(prompt, echo);
+               response = read_passphrase(prompt, echo ? RP_ECHO : 0);
 
                packet_put_cstring(response);
                memset(response, 0, strlen(response));
                xfree(response);
                xfree(prompt);
        }
-       packet_done(); /* done with parsing incoming message. */
+       packet_check_eom(); /* done with parsing incoming message. */
 
-       packet_inject_ignore(64);
+       packet_add_padding(64);
        packet_send();
 }
 
-/* find auth method */
+static int
+ssh_keysign(
+    Key *key,
+    u_char **sigp, u_int *lenp,
+    u_char *data, u_int datalen)
+{
+       Buffer b;
+       struct stat st;
+       pid_t pid;
+       int to[2], from[2], status, version = 2;
 
-#define        DELIM   ","
+       debug("ssh_keysign called");
 
-static char *def_authlist = "publickey,password";
-static char *authlist_current = NULL;   /* clean copy used for comparison */
-static char *authname_current = NULL;   /* last used auth method */
-static char *authlist_working = NULL;   /* copy that gets modified by strtok_r() */
-static char *authlist_state = NULL;     /* state variable for strtok_r() */
+       if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) {
+               error("ssh_keysign: no installed: %s", strerror(errno));
+               return -1;
+       }
+       if (fflush(stdout) != 0)
+               error("ssh_keysign: fflush: %s", strerror(errno));
+       if (pipe(to) < 0) {
+               error("ssh_keysign: pipe: %s", strerror(errno));
+               return -1;
+       }
+       if (pipe(from) < 0) {
+               error("ssh_keysign: pipe: %s", strerror(errno));
+               return -1;
+       }
+       if ((pid = fork()) < 0) {
+               error("ssh_keysign: fork: %s", strerror(errno));
+               return -1;
+       }
+       if (pid == 0) {
+               seteuid(getuid());
+               setuid(getuid());
+               close(from[0]);
+               if (dup2(from[1], STDOUT_FILENO) < 0)
+                       fatal("ssh_keysign: dup2: %s", strerror(errno));
+               close(to[1]);
+               if (dup2(to[0], STDIN_FILENO) < 0)
+                       fatal("ssh_keysign: dup2: %s", strerror(errno));
+               close(from[1]);
+               close(to[0]);
+               execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0);
+               fatal("ssh_keysign: exec(%s): %s", _PATH_SSH_KEY_SIGN,
+                   strerror(errno));
+       }
+       close(from[1]);
+       close(to[0]);
 
-/*
- * Before starting to use a new authentication method list sent by the
- * server, reset internal variables.  This should also be called when
- * finished processing server list to free resources.
- */
-void
-authmethod_clear(void)
+       buffer_init(&b);
+       buffer_put_int(&b, packet_get_connection_in()); /* send # of socket */
+       buffer_put_string(&b, data, datalen);
+       msg_send(to[1], version, &b);
+
+       if (msg_recv(from[0], &b) < 0) {
+               error("ssh_keysign: no reply");
+               buffer_clear(&b);
+               return -1;
+       }
+       close(from[0]);
+       close(to[1]);
+
+       while (waitpid(pid, &status, 0) < 0)
+               if (errno != EINTR)
+                       break;
+
+       if (buffer_get_char(&b) != version) {
+               error("ssh_keysign: bad version");
+               buffer_clear(&b);
+               return -1;
+       }
+       *sigp = buffer_get_string(&b, lenp);
+       buffer_clear(&b);
+
+       return 0;
+}
+
+int
+userauth_hostbased(Authctxt *authctxt)
 {
-       if (authlist_current != NULL) {
-               xfree(authlist_current);
-               authlist_current = NULL;
+       Key *private = NULL;
+       Sensitive *sensitive = authctxt->sensitive;
+       Buffer b;
+       u_char *signature, *blob;
+       char *chost, *pkalg, *p;
+       const char *service;
+       u_int blen, slen;
+       int ok, i, len, found = 0;
+
+       /* check for a useful key */
+       for (i = 0; i < sensitive->nkeys; i++) {
+               private = sensitive->keys[i];
+               if (private && private->type != KEY_RSA1) {
+                       found = 1;
+                       /* we take and free the key */
+                       sensitive->keys[i] = NULL;
+                       break;
+               }
        }
-       if (authlist_working != NULL) {
-               xfree(authlist_working);
-               authlist_working = NULL;
+       if (!found) {
+               debug("userauth_hostbased: no more client hostkeys");
+               return 0;
        }
-       if (authname_current != NULL) {
-               xfree(authname_current);
-               authname_current = NULL;
+       if (key_to_blob(private, &blob, &blen) == 0) {
+               key_free(private);
+               return 0;
        }
-       if (authlist_state != NULL)
-               authlist_state = NULL;
-       return;
+       /* figure out a name for the client host */
+       p = get_local_name(packet_get_connection_in());
+       if (p == NULL) {
+               error("userauth_hostbased: cannot get local ipaddr/name");
+               key_free(private);
+               return 0;
+       }
+       len = strlen(p) + 2;
+       chost = xmalloc(len);
+       strlcpy(chost, p, len);
+       strlcat(chost, ".", len);
+       debug2("userauth_hostbased: chost %s", chost);
+
+       service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
+           authctxt->service;
+       pkalg = xstrdup(key_ssh_name(private));
+       buffer_init(&b);
+       /* construct data */
+       buffer_put_string(&b, session_id2, session_id2_len);
+       buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
+       buffer_put_cstring(&b, authctxt->server_user);
+       buffer_put_cstring(&b, service);
+       buffer_put_cstring(&b, authctxt->method->name);
+       buffer_put_cstring(&b, pkalg);
+       buffer_put_string(&b, blob, blen);
+       buffer_put_cstring(&b, chost);
+       buffer_put_cstring(&b, authctxt->local_user);
+#ifdef DEBUG_PK
+       buffer_dump(&b);
+#endif
+       if (sensitive->external_keysign)
+               ok = ssh_keysign(private, &signature, &slen,
+                   buffer_ptr(&b), buffer_len(&b));
+       else
+               ok = key_sign(private, &signature, &slen,
+                   buffer_ptr(&b), buffer_len(&b));
+       key_free(private);
+       buffer_free(&b);
+       if (ok != 0) {
+               error("key_sign failed");
+               xfree(chost);
+               xfree(pkalg);
+               return 0;
+       }
+       packet_start(SSH2_MSG_USERAUTH_REQUEST);
+       packet_put_cstring(authctxt->server_user);
+       packet_put_cstring(authctxt->service);
+       packet_put_cstring(authctxt->method->name);
+       packet_put_cstring(pkalg);
+       packet_put_string(blob, blen);
+       packet_put_cstring(chost);
+       packet_put_cstring(authctxt->local_user);
+       packet_put_string(signature, slen);
+       memset(signature, 's', slen);
+       xfree(signature);
+       xfree(chost);
+       xfree(pkalg);
+
+       packet_send();
+       return 1;
 }
 
+/* find auth method */
+
 /*
  * given auth method name, if configurable options permit this method fill
  * in auth_ident field and return true, otherwise return false.
  */
-int
+static int
 authmethod_is_enabled(Authmethod *method)
 {
        if (method == NULL)
@@ -1152,7 +1082,7 @@ authmethod_is_enabled(Authmethod *method)
        return 1;
 }
 
-Authmethod *
+static Authmethod *
 authmethod_lookup(const char *name)
 {
        Authmethod *method = NULL;
@@ -1164,62 +1094,72 @@ authmethod_lookup(const char *name)
        return NULL;
 }
 
+/* XXX internal state */
+static Authmethod *current = NULL;
+static char *supported = NULL;
+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.  If the server sends a nil list after
- * previously sending a valid list, continue using the list originally
- * sent.
+ * use a built-in default list.
  */
-
-Authmethod *
+static Authmethod *
 authmethod_get(char *authlist)
 {
-       char *name = NULL, *authname_old;
-       Authmethod *method = NULL;
+
+       char *name = NULL;
+       u_int next;
 
        /* Use a suitable default if we're passed a nil list.  */
        if (authlist == NULL || strlen(authlist) == 0)
-               authlist = def_authlist;
-
-       if (authlist_current == NULL || strcmp(authlist, authlist_current) != 0) {
-               /* start over if passed a different list */
-               debug3("start over, passed a different list");
-               authmethod_clear();
-               authlist_current = xstrdup(authlist);
-               authlist_working = xstrdup(authlist);
-               name = strtok_r(authlist_working, DELIM, &authlist_state);
-       } else {
-               /*
-                * try to use previously used authentication method
-                * or continue to use previously passed list
-                */
-               name = (authname_current != NULL) ?
-                   authname_current : strtok_r(NULL, DELIM, &authlist_state);
-       }
+               authlist = options.preferred_authentications;
+
+       if (supported == NULL || strcmp(authlist, supported) != 0) {
+               debug3("start over, passed a different list %s", authlist);
+               if (supported != NULL)
+                       xfree(supported);
+               supported = xstrdup(authlist);
+               preferred = options.preferred_authentications;
+               debug3("preferred %s", preferred);
+               current = NULL;
+       } else if (current != NULL && authmethod_is_enabled(current))
+               return current;
 
-       while (name != NULL) {
+       for (;;) {
+               if ((name = match_list(preferred, supported, &next)) == NULL) {
+                       debug("no more auth methods to try");
+                       current = NULL;
+                       return NULL;
+               }
+               preferred += next;
                debug3("authmethod_lookup %s", name);
-               method = authmethod_lookup(name);
-               if (method != NULL && authmethod_is_enabled(method)) {
+               debug3("remaining preferred: %s", preferred);
+               if ((current = authmethod_lookup(name)) != NULL &&
+                   authmethod_is_enabled(current)) {
                        debug3("authmethod_is_enabled %s", name);
-                       break;
+                       debug("next auth method to try is %s", name);
+                       return current;
                }
-               name = strtok_r(NULL, DELIM, &authlist_state);
-               method = NULL;
-       }
-
-       authname_old = authname_current;
-       if (method != NULL) {
-               debug("next auth method to try is %s", name);
-               authname_current = xstrdup(name);
-       } else {
-               debug("no more auth methods to try");
-               authname_current = NULL;
        }
+}
 
-       if (authname_old != NULL)
-               xfree(authname_old);
+static char *
+authmethods_get(void)
+{
+       Authmethod *method = NULL;
+       Buffer b;
+       char *list;
 
-       return (method);
+       buffer_init(&b);
+       for (method = authmethods; method->name != NULL; method++) {
+               if (authmethod_is_enabled(method)) {
+                       if (buffer_len(&b) > 0)
+                               buffer_append(&b, ",", 1);
+                       buffer_append(&b, method->name, strlen(method->name));
+               }
+       }
+       buffer_append(&b, "\0", 1);
+       list = xstrdup(buffer_ptr(&b));
+       buffer_free(&b);
+       return list;
 }
This page took 0.097777 seconds and 4 git commands to generate.