=================================================================== RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/ssh/sshconnect2.c,v retrieving revision 1.99 retrieving revision 1.99.2.3 diff -u -r1.99 -r1.99.2.3 --- src/usr.bin/ssh/sshconnect2.c 2002/03/26 15:58:46 1.99 +++ src/usr.bin/ssh/sshconnect2.c 2003/04/03 22:35:18 1.99.2.3 @@ -23,7 +23,7 @@ */ #include "includes.h" -RCSID("$OpenBSD: sshconnect2.c,v 1.99 2002/03/26 15:58:46 markus Exp $"); +RCSID("$OpenBSD: sshconnect2.c,v 1.99.2.3 2003/04/03 22:35:18 miod Exp $"); #include "ssh.h" #include "ssh2.h" @@ -45,6 +45,8 @@ #include "match.h" #include "dispatch.h" #include "canohost.h" +#include "msg.h" +#include "pathnames.h" /* import */ extern char *client_version_string; @@ -93,10 +95,10 @@ compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_STOC]); if (options.compression) { myproposal[PROPOSAL_COMP_ALGS_CTOS] = - myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib"; + myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib,none"; } else { myproposal[PROPOSAL_COMP_ALGS_CTOS] = - myproposal[PROPOSAL_COMP_ALGS_STOC] = "none"; + myproposal[PROPOSAL_COMP_ALGS_STOC] = "none,zlib"; } if (options.macs != NULL) { myproposal[PROPOSAL_MAC_ALGS_CTOS] = @@ -108,6 +110,8 @@ /* start key exchange */ kex = kex_setup(myproposal); + kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client; + kex->kex[KEX_DH_GEX_SHA1] = kexgex_client; kex->client_version_string=client_version_string; kex->server_version_string=server_version_string; kex->verify_host_key=&verify_host_key_callback; @@ -126,7 +130,6 @@ packet_send(); packet_write_wait(); #endif - debug("done: ssh_kex2."); } /* @@ -154,8 +157,7 @@ int last_key_hint; AuthenticationConnection *agent; /* hostbased */ - Key **keys; - int nkeys; + Sensitive *sensitive; /* kbd-interactive */ int info_req_seen; }; @@ -215,7 +217,7 @@ void ssh_userauth2(const char *local_user, const char *server_user, char *host, - Key **keys, int nkeys) + Sensitive *sensitive) { Authctxt authctxt; int type; @@ -223,24 +225,23 @@ if (options.challenge_response_authentication) options.kbd_interactive_authentication = 1; - debug("send SSH2_MSG_SERVICE_REQUEST"); packet_start(SSH2_MSG_SERVICE_REQUEST); packet_put_cstring("ssh-userauth"); packet_send(); + debug("SSH2_MSG_SERVICE_REQUEST sent"); packet_write_wait(); type = packet_read(); - if (type != SSH2_MSG_SERVICE_ACCEPT) { - fatal("denied SSH2_MSG_SERVICE_ACCEPT: %d", type); - } + if (type != SSH2_MSG_SERVICE_ACCEPT) + fatal("Server denied authentication request: %d", type); if (packet_remaining() > 0) { char *reply = packet_get_string(NULL); - debug("service_accept: %s", reply); + debug2("service_accept: %s", reply); xfree(reply); } else { - debug("buggy server: service_accept w/o service"); + debug2("buggy server: service_accept w/o service"); } packet_check_eom(); - debug("got SSH2_MSG_SERVICE_ACCEPT"); + debug("SSH2_MSG_SERVICE_ACCEPT received"); if (options.preferred_authentications == NULL) options.preferred_authentications = authmethods_get(); @@ -255,8 +256,7 @@ authctxt.success = 0; authctxt.method = authmethod_lookup("none"); authctxt.authlist = NULL; - authctxt.keys = keys; - authctxt.nkeys = nkeys; + authctxt.sensitive = sensitive; authctxt.info_req_seen = 0; if (authctxt.method == NULL) fatal("ssh_userauth2: internal error: cannot send userauth none request"); @@ -273,7 +273,7 @@ if (authctxt.agent != NULL) ssh_close_authentication_connection(authctxt.agent); - debug("ssh-userauth2 successful: method %s", authctxt.method->name); + debug("Authentication succeeded (%s).", authctxt.method->name); } void userauth(Authctxt *authctxt, char *authlist) @@ -299,12 +299,14 @@ } } } + void 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, u_int32_t seq, void *ctxt) { @@ -316,6 +318,7 @@ xfree(msg); xfree(lang); } + void input_userauth_success(int type, u_int32_t seq, void *ctxt) { @@ -327,6 +330,7 @@ clear_auth_state(authctxt); authctxt->success = 1; /* break out */ } + void input_userauth_failure(int type, u_int32_t seq, void *ctxt) { @@ -343,7 +347,7 @@ if (partial != 0) log("Authenticated with partial success."); - debug("authentications that can continue: %s", authlist); + debug("Authentications that can continue: %s", authlist); clear_auth_state(authctxt); userauth(authctxt, authlist); @@ -375,7 +379,7 @@ } packet_check_eom(); - debug("input_userauth_pk_ok: pkalg %s blen %d lastkey %p hint %d", + debug("Server accepts key: pkalg %s blen %u lastkey %p hint %d", pkalg, blen, authctxt->last_key, authctxt->last_key_hint); do { @@ -395,7 +399,7 @@ if (key->type != pktype) { error("input_userauth_pk_ok: type mismatch " "for decoded key (received %d, expected %d)", - key->type, pktype); + key->type, pktype); break; } fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX); @@ -418,7 +422,7 @@ clear_auth_state(authctxt); dispatch_set(SSH2_MSG_USERAUTH_PK_OK, NULL); - /* try another method if we did not send a packet*/ + /* try another method if we did not send a packet */ if (sent == 0) userauth(authctxt, NULL); @@ -463,7 +467,7 @@ packet_add_padding(64); packet_send(); - dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, + dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, &input_userauth_passwd_changereq); return 1; @@ -495,7 +499,7 @@ packet_put_cstring(authctxt->service); packet_put_cstring(authctxt->method->name); packet_put_char(1); /* additional info */ - snprintf(prompt, sizeof(prompt), + snprintf(prompt, sizeof(prompt), "Enter %.30s@%.128s's old password: ", authctxt->server_user, authctxt->host); password = read_passphrase(prompt, 0); @@ -504,7 +508,7 @@ xfree(password); password = NULL; while (password == NULL) { - snprintf(prompt, sizeof(prompt), + snprintf(prompt, sizeof(prompt), "Enter %.30s@%.128s's new password: ", authctxt->server_user, authctxt->host); password = read_passphrase(prompt, RP_ALLOW_EOF); @@ -512,7 +516,7 @@ /* bail out */ return; } - snprintf(prompt, sizeof(prompt), + snprintf(prompt, sizeof(prompt), "Retype %.30s@%.128s's new password: ", authctxt->server_user, authctxt->host); retype = read_passphrase(prompt, 0); @@ -530,8 +534,8 @@ xfree(password); packet_add_padding(64); packet_send(); - - dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, + + dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, &input_userauth_passwd_changereq); } @@ -760,7 +764,7 @@ if (k == NULL) { debug2("userauth_pubkey_agent: no more keys"); } else { - debug("userauth_pubkey_agent: testing agent key %s", comment); + debug("Offering agent key: %s", comment); xfree(comment); ret = send_pubkey_test(authctxt, k, agent_sign_cb, -1); if (ret == 0) @@ -788,7 +792,7 @@ key = options.identity_keys[idx]; filename = options.identity_files[idx]; if (key == NULL) { - debug("try privkey: %s", filename); + debug("Trying private key: %s", filename); key = load_identity_file(filename); if (key != NULL) { sent = sign_and_send_pubkey(authctxt, key, @@ -796,7 +800,7 @@ key_free(key); } } else if (key->type != KEY_RSA1) { - debug("try pubkey: %s", filename); + debug("Offering public key: %s", filename); sent = send_pubkey_test(authctxt, key, identity_sign_cb, idx); } @@ -893,14 +897,86 @@ packet_send(); } -/* - * this will be move to an external program (ssh-keysign) ASAP. ssh-keysign - * will be setuid-root and the sbit can be removed from /usr/bin/ssh. - */ +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; + + debug2("ssh_keysign called"); + + 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]); + + buffer_init(&b); + buffer_put_int(&b, packet_get_connection_in()); /* send # of socket */ + buffer_put_string(&b, data, datalen); + ssh_msg_send(to[1], version, &b); + + if (ssh_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) { Key *private = NULL; + Sensitive *sensitive = authctxt->sensitive; Buffer b; u_char *signature, *blob; char *chost, *pkalg, *p; @@ -909,17 +985,17 @@ int ok, i, len, found = 0; /* check for a useful key */ - for (i = 0; i < authctxt->nkeys; i++) { - private = authctxt->keys[i]; + 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 */ - authctxt->keys[i] = NULL; + sensitive->keys[i] = NULL; break; } } if (!found) { - debug("userauth_hostbased: no more client hostkeys"); + debug("No more client hostkeys for hostbased authentication."); return 0; } if (key_to_blob(private, &blob, &blen) == 0) { @@ -938,6 +1014,7 @@ strlcpy(chost, p, len); strlcat(chost, ".", len); debug2("userauth_hostbased: chost %s", chost); + xfree(p); service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" : authctxt->service; @@ -956,7 +1033,12 @@ #ifdef DEBUG_PK buffer_dump(&b); #endif - ok = key_sign(private, &signature, &slen, buffer_ptr(&b), buffer_len(&b)); + 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) { @@ -1019,6 +1101,7 @@ 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, @@ -1027,7 +1110,6 @@ static Authmethod * authmethod_get(char *authlist) { - char *name = NULL; u_int next; @@ -1048,7 +1130,7 @@ for (;;) { if ((name = match_list(preferred, supported, &next)) == NULL) { - debug("no more auth methods to try"); + debug("No more authentication methods to try."); current = NULL; return NULL; } @@ -1058,7 +1140,7 @@ if ((current = authmethod_lookup(name)) != NULL && authmethod_is_enabled(current)) { debug3("authmethod_is_enabled %s", name); - debug("next auth method to try is %s", name); + debug("Next authentication method: %s", name); return current; } }