X-Git-Url: http://andersk.mit.edu/gitweb/gssapi-openssh.git/blobdiff_plain/996d5e62b203304a38c5c400d764db9ff9121b48..799ae497fc1f308e76517858d866bdd27b56cdd8:/openssh/session.c diff --git a/openssh/session.c b/openssh/session.c index b32c9e2..4c97c4a 100644 --- a/openssh/session.c +++ b/openssh/session.c @@ -1,3 +1,4 @@ +/* $OpenBSD: session.c,v 1.221 2007/01/21 01:41:54 stevesk Exp $ */ /* * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland * All rights reserved @@ -33,12 +34,35 @@ */ #include "includes.h" -RCSID("$OpenBSD: session.c,v 1.181 2004/12/23 17:35:48 markus Exp $"); +#include +#include +#ifdef HAVE_SYS_STAT_H +# include +#endif +#include +#include +#include + +#include + +#include +#include +#ifdef HAVE_PATHS_H +#include +#endif +#include +#include +#include +#include +#include +#include +#include + +#include "xmalloc.h" #include "ssh.h" #include "ssh1.h" #include "ssh2.h" -#include "xmalloc.h" #include "sshpty.h" #include "packet.h" #include "buffer.h" @@ -46,7 +70,12 @@ RCSID("$OpenBSD: session.c,v 1.181 2004/12/23 17:35:48 markus Exp $"); #include "uidswap.h" #include "compat.h" #include "channels.h" -#include "bufaux.h" +#include "key.h" +#include "cipher.h" +#ifdef GSSAPI +#include "ssh-gss.h" +#endif +#include "hostfile.h" #include "auth.h" #include "auth-options.h" #include "pathnames.h" @@ -56,16 +85,13 @@ RCSID("$OpenBSD: session.c,v 1.181 2004/12/23 17:35:48 markus Exp $"); #include "serverloop.h" #include "canohost.h" #include "session.h" +#include "kex.h" #include "monitor_wrap.h" #if defined(KRB5) && defined(USE_AFS) #include #endif -#ifdef GSSAPI -#include "ssh-gss.h" -#endif - /* func */ Session *session_new(void); @@ -174,7 +200,7 @@ auth_input_request_forwarding(struct passwd * pw) sunaddr.sun_family = AF_UNIX; strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path)); - if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) + if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) < 0) packet_disconnect("bind: %.100s", strerror(errno)); /* Restore the privileged uid. */ @@ -196,11 +222,11 @@ auth_input_request_forwarding(struct passwd * pw) static void display_loginmsg(void) { - if (buffer_len(&loginmsg) > 0) { - buffer_append(&loginmsg, "\0", 1); - printf("%s", (char *)buffer_ptr(&loginmsg)); - buffer_clear(&loginmsg); - } + if (buffer_len(&loginmsg) > 0) { + buffer_append(&loginmsg, "\0", 1); + printf("%s", (char *)buffer_ptr(&loginmsg)); + buffer_clear(&loginmsg); + } } void @@ -208,15 +234,6 @@ do_authenticated(Authctxt *authctxt) { setproctitle("%s", authctxt->pw->pw_name); - /* - * Cancel the alarm we set to limit the time taken for - * authentication. - */ - alarm(0); - if (startup_pipe != -1) { - close(startup_pipe); - startup_pipe = -1; - } /* setup the channel layer */ if (!no_port_forwarding_flag && options.allow_tcp_forwarding) channel_permit_all_opens(); @@ -272,7 +289,7 @@ do_authenticated1(Authctxt *authctxt) compression_level); break; } - if (!options.compression) { + if (options.compression == COMP_NONE) { debug2("compression disabled"); break; } @@ -330,7 +347,11 @@ do_authenticated1(Authctxt *authctxt) break; } debug("Received TCP/IP port forwarding request."); - channel_input_port_forward_request(s->pw->pw_uid == 0, options.gateway_ports); + if (channel_input_port_forward_request(s->pw->pw_uid == 0, + options.gateway_ports) < 0) { + debug("Port forwarding failed."); + break; + } success = 1; break; @@ -640,7 +661,7 @@ do_pre_login(Session *s) fromlen = sizeof(from); if (packet_connection_is_on_socket()) { if (getpeername(packet_get_connection_in(), - (struct sockaddr *) & from, &fromlen) < 0) { + (struct sockaddr *)&from, &fromlen) < 0) { debug("getpeername: %.100s", strerror(errno)); cleanup_exit(255); } @@ -659,10 +680,14 @@ do_pre_login(Session *s) void do_exec(Session *s, const char *command) { - if (forced_command) { + if (options.adm_forced_command) { + original_command = command; + command = options.adm_forced_command; + debug("Forced command (config) '%.900s'", command); + } else if (forced_command) { original_command = command; command = forced_command; - debug("Forced command '%.900s'", command); + debug("Forced command (key option) '%.900s'", command); } #ifdef SSH_AUDIT_EVENTS @@ -834,7 +859,7 @@ child_set_env(char ***envp, u_int *envsizep, const char *name, if (envsize >= 1000) fatal("child_set_env: too many env vars"); envsize += 50; - env = (*envp) = xrealloc(env, envsize * sizeof(char *)); + env = (*envp) = xrealloc(env, envsize, sizeof(char *)); *envsizep = envsize; } /* Need to set the NULL pointer at end of array beyond the new slot. */ @@ -946,7 +971,8 @@ read_etc_default_login(char ***env, u_int *envsize, uid_t uid) } #endif /* HAVE_ETC_DEFAULT_LOGIN */ -void copy_environment(char **source, char ***env, u_int *envsize) +void +copy_environment(char **source, char ***env, u_int *envsize) { char *var_name, *var_val; int i; @@ -974,12 +1000,15 @@ do_setup_env(Session *s, const char *shell) { char buf[256]; u_int i, envsize; - char **env, *laddr, *path = NULL; + char **env, *laddr; struct passwd *pw = s->pw; +#ifndef HAVE_LOGIN_CAP + char *path = NULL; +#endif /* Initialize the environment. */ envsize = 100; - env = xmalloc(envsize * sizeof(char *)); + env = xcalloc(envsize, sizeof(char *)); env[0] = NULL; #ifdef HAVE_CYGWIN @@ -1332,6 +1361,11 @@ do_setusercontext(struct passwd *pw) # ifdef _AIX aix_usrinfo(pw); # endif /* _AIX */ +#if defined(HAVE_LIBIAF) && !defined(BROKEN_LIBIAF) + if (set_id(pw->pw_name) != 0) { + exit(1); + } +#endif /* HAVE_LIBIAF && !BROKEN_LIBIAF */ /* Permanently switch to the desired uid. */ permanently_set_uid(pw); #endif @@ -1342,6 +1376,10 @@ do_setusercontext(struct passwd *pw) #endif if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid) fatal("Failed to set uids to %u.", (u_int) pw->pw_uid); + +#ifdef WITH_SELINUX + ssh_selinux_setup_exec_context(pw->pw_name); +#endif } static void @@ -1412,7 +1450,7 @@ child_close_fds(void) endpwent(); /* - * Close any extra open file descriptors so that we don\'t have them + * Close any extra open file descriptors so that we don't have them * hanging around in clients. Note that we want to do this after * initgroups, because at least on Solaris 2.3 it leaves file * descriptors open. @@ -1464,7 +1502,9 @@ do_child(Session *s, const char *command) if (!check_quietlogin(s, command)) do_motd(); #else /* HAVE_OSF_SIA */ - do_nologin(pw); + /* When PAM is enabled we rely on it to do the nologin check */ + if (!options.use_pam) + do_nologin(pw); do_setusercontext(pw); /* * PAM session modules in do_setusercontext may have @@ -1477,7 +1517,8 @@ do_child(Session *s, const char *command) } #ifdef USE_PAM - if (options.use_pam && !is_pam_session_open()) { + if (options.use_pam && !options.use_login && !is_pam_session_open()) { + debug3("PAM session not opened, exiting"); display_loginmsg(); exit(254); } @@ -1528,7 +1569,7 @@ do_child(Session *s, const char *command) */ if (options.kerberos_get_afs_token && k_hasafs() && - (s->authctxt->krb5_ctx != NULL)) { + (s->authctxt->krb5_ctx != NULL)) { char cell[64]; debug("Getting AFS token"); @@ -1544,7 +1585,7 @@ do_child(Session *s, const char *command) } #endif - /* Change current directory to the user\'s home directory. */ + /* Change current directory to the user's home directory. */ if (chdir(pw->pw_dir) < 0) { fprintf(stderr, "Could not chdir to home directory %s: %s\n", pw->pw_dir, strerror(errno)); @@ -1558,7 +1599,7 @@ do_child(Session *s, const char *command) do_rc_files(s, shell); /* restore SIGPIPE for child */ - signal(SIGPIPE, SIG_DFL); + signal(SIGPIPE, SIG_DFL); if (options.use_login) { launch_login(pw, hostname); @@ -1632,6 +1673,7 @@ session_new(void) s->ttyfd = -1; s->used = 1; s->self = i; + s->x11_chanids = NULL; debug("session_new: session %d", i); return s; } @@ -1704,6 +1746,29 @@ session_by_channel(int id) return NULL; } +static Session * +session_by_x11_channel(int id) +{ + int i, j; + + for (i = 0; i < MAX_SESSIONS; i++) { + Session *s = &sessions[i]; + + if (s->x11_chanids == NULL || !s->used) + continue; + for (j = 0; s->x11_chanids[j] != -1; j++) { + if (s->x11_chanids[j] == id) { + debug("session_by_x11_channel: session %d " + "channel %d", s->self, id); + return s; + } + } + } + debug("session_by_x11_channel: unknown channel %d", id); + session_dump(); + return NULL; +} + static Session * session_by_pid(pid_t pid) { @@ -1798,17 +1863,18 @@ session_subsystem_req(Session *s) struct stat st; u_int len; int success = 0; - char *cmd, *subsys = packet_get_string(&len); - int i; + char *prog, *cmd, *subsys = packet_get_string(&len); + u_int i; packet_check_eom(); logit("subsystem request for %.100s", subsys); for (i = 0; i < options.num_subsystems; i++) { if (strcmp(subsys, options.subsystem_name[i]) == 0) { - cmd = options.subsystem_command[i]; - if (stat(cmd, &st) < 0) { - error("subsystem: cannot stat %s: %s", cmd, + prog = options.subsystem_command[i]; + cmd = options.subsystem_args[i]; + if (stat(prog, &st) < 0) { + error("subsystem: cannot stat %s: %s", prog, strerror(errno)); break; } @@ -1833,6 +1899,11 @@ session_x11_req(Session *s) { int success; + if (s->auth_proto != NULL || s->auth_data != NULL) { + error("session_x11_req: session %d: " + "x11 forwarding already active", s->self); + return 0; + } s->single_connection = packet_get_char(); s->auth_proto = packet_get_string(NULL); s->auth_data = packet_get_string(NULL); @@ -1900,8 +1971,8 @@ session_env_req(Session *s) for (i = 0; i < options.num_accept_env; i++) { if (match_pattern(name, options.accept_env[i])) { debug2("Setting env %d: %s=%s", s->num_env, name, val); - s->env = xrealloc(s->env, sizeof(*s->env) * - (s->num_env + 1)); + s->env = xrealloc(s->env, s->num_env + 1, + sizeof(*s->env)); s->env[s->num_env].name = name; s->env[s->num_env].val = val; s->num_env++; @@ -1956,7 +2027,7 @@ session_input_channel_req(Channel *c, const char *rtype) } else if (strcmp(rtype, "exec") == 0) { success = session_exec_req(s); } else if (strcmp(rtype, "pty-req") == 0) { - success = session_pty_req(s); + success = session_pty_req(s); } else if (strcmp(rtype, "x11-req") == 0) { success = session_x11_req(s); } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) { @@ -2057,6 +2128,62 @@ sig2name(int sig) return "SIG@openssh.com"; } +static void +session_close_x11(int id) +{ + Channel *c; + + if ((c = channel_by_id(id)) == NULL) { + debug("session_close_x11: x11 channel %d missing", id); + } else { + /* Detach X11 listener */ + debug("session_close_x11: detach x11 channel %d", id); + channel_cancel_cleanup(id); + if (c->ostate != CHAN_OUTPUT_CLOSED) + chan_mark_dead(c); + } +} + +static void +session_close_single_x11(int id, void *arg) +{ + Session *s; + u_int i; + + debug3("session_close_single_x11: channel %d", id); + channel_cancel_cleanup(id); + if ((s = session_by_x11_channel(id)) == NULL) + fatal("session_close_single_x11: no x11 channel %d", id); + for (i = 0; s->x11_chanids[i] != -1; i++) { + debug("session_close_single_x11: session %d: " + "closing channel %d", s->self, s->x11_chanids[i]); + /* + * The channel "id" is already closing, but make sure we + * close all of its siblings. + */ + if (s->x11_chanids[i] != id) + session_close_x11(s->x11_chanids[i]); + } + xfree(s->x11_chanids); + s->x11_chanids = NULL; + if (s->display) { + xfree(s->display); + s->display = NULL; + } + if (s->auth_proto) { + xfree(s->auth_proto); + s->auth_proto = NULL; + } + if (s->auth_data) { + xfree(s->auth_data); + s->auth_data = NULL; + } + if (s->auth_display) { + xfree(s->auth_display); + s->auth_display = NULL; + } +} + static void session_exit_message(Session *s, int status) { @@ -2090,7 +2217,14 @@ session_exit_message(Session *s, int status) /* disconnect channel */ debug("session_exit_message: release channel %d", s->chanid); - channel_cancel_cleanup(s->chanid); + + /* + * Adjust cleanup callback attachment to send close messages when + * the channel gets EOF. The session will be then be closed + * by session_close_by_channel when the childs close their fds. + */ + channel_register_cleanup(c->self, session_close_by_channel, 1); + /* * emulate a write failure with 'chan_write_failed', nobody will be * interested in data we write. @@ -2099,13 +2233,12 @@ session_exit_message(Session *s, int status) */ if (c->ostate != CHAN_OUTPUT_CLOSED) chan_write_failed(c); - s->chanid = -1; } void session_close(Session *s) { - int i; + u_int i; debug("session_close: session %d pid %ld", s->self, (long)s->pid); if (s->ttyfd != -1) @@ -2114,6 +2247,8 @@ session_close(Session *s) xfree(s->term); if (s->display) xfree(s->display); + if (s->x11_chanids) + xfree(s->x11_chanids); if (s->auth_display) xfree(s->auth_display); if (s->auth_data) @@ -2121,12 +2256,13 @@ session_close(Session *s) if (s->auth_proto) xfree(s->auth_proto); s->used = 0; - for (i = 0; i < s->num_env; i++) { - xfree(s->env[i].name); - xfree(s->env[i].val); - } - if (s->env != NULL) + if (s->env != NULL) { + for (i = 0; i < s->num_env; i++) { + xfree(s->env[i].name); + xfree(s->env[i].val); + } xfree(s->env); + } session_proctitle(s); } @@ -2141,7 +2277,9 @@ session_close_by_pid(pid_t pid, int status) } if (s->chanid != -1) session_exit_message(s, status); - session_close(s); + if (s->ttyfd != -1) + session_pty_cleanup(s); + s->pid = 0; } /* @@ -2152,6 +2290,8 @@ void session_close_by_channel(int id, void *arg) { Session *s = session_by_channel(id); + u_int i; + if (s == NULL) { debug("session_close_by_channel: no session for id %d", id); return; @@ -2170,6 +2310,15 @@ session_close_by_channel(int id, void *arg) } /* detach by removing callback */ channel_cancel_cleanup(s->chanid); + + /* Close any X11 listeners associated with this session */ + if (s->x11_chanids != NULL) { + for (i = 0; s->x11_chanids[i] != -1; i++) { + session_close_x11(s->x11_chanids[i]); + s->x11_chanids[i] = -1; + } + } + s->chanid = -1; session_close(s); } @@ -2232,6 +2381,7 @@ session_setup_x11fwd(Session *s) struct stat st; char display[512], auth_display[512]; char hostname[MAXHOSTNAMELEN]; + u_int i; if (no_x11_forwarding_flag) { packet_send_debug("X11 forwarding disabled in user configuration file."); @@ -2257,10 +2407,14 @@ session_setup_x11fwd(Session *s) } if (x11_create_display_inet(options.x11_display_offset, options.x11_use_localhost, s->single_connection, - &s->display_number) == -1) { + &s->display_number, &s->x11_chanids) == -1) { debug("x11_create_display_inet failed."); return 0; } + for (i = 0; s->x11_chanids[i] != -1; i++) { + channel_register_cleanup(s->x11_chanids[i], + session_close_single_x11, 0); + } /* Set up a suitable value for the DISPLAY variable. */ if (gethostname(hostname, sizeof(hostname)) < 0) @@ -2324,7 +2478,7 @@ do_cleanup(Authctxt *authctxt) return; called = 1; - if (authctxt == NULL) + if (authctxt == NULL || !authctxt->authenticated) return; #ifdef KRB5 if (options.kerberos_ticket_cleanup &&