X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/2e73a022769fe8381d733b1ad00d8a106708216f..c95add71a6006659751a44208b4ec0cedc82c0b0:/session.c diff --git a/session.c b/session.c index 82096c3a..fbdc419e 100644 --- a/session.c +++ b/session.c @@ -1,44 +1,80 @@ /* * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland * All rights reserved - */ -/* + * + * As far as I am concerned, the code I have written for this software + * can be used freely for any purpose. Any derived versions of this + * software must be clearly marked as such, and if the derived work is + * incompatible with the protocol description in the RFC file, it must be + * called by a name other than "ssh" or "Secure Shell". + * * SSH2 support by Markus Friedl. - * Copyright (c) 2000 Markus Friedl. All rights reserved. + * Copyright (c) 2000 Markus Friedl. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include "includes.h" -RCSID("$OpenBSD: session.c,v 1.29 2000/08/21 16:23:31 millert Exp $"); +RCSID("$OpenBSD: session.c,v 1.92 2001/06/19 15:40:45 markus Exp $"); -#include "xmalloc.h" #include "ssh.h" -#include "pty.h" +#include "ssh1.h" +#include "ssh2.h" +#include "xmalloc.h" +#include "sshpty.h" #include "packet.h" #include "buffer.h" -#include "cipher.h" #include "mpaux.h" -#include "servconf.h" #include "uidswap.h" #include "compat.h" #include "channels.h" -#include "nchan.h" - #include "bufaux.h" -#include "ssh2.h" #include "auth.h" #include "auth-options.h" +#include "pathnames.h" +#include "log.h" +#include "servconf.h" +#include "sshlogin.h" +#include "serverloop.h" +#include "canohost.h" +#include "session.h" #ifdef WITH_IRIX_PROJECT #include #endif /* WITH_IRIX_PROJECT */ +#ifdef WITH_IRIX_JOBS +#include +#endif +#ifdef WITH_IRIX_AUDIT +#include +#endif /* WITH_IRIX_AUDIT */ #if defined(HAVE_USERSEC_H) #include #endif -#ifdef HAVE_OSF_SIA -# include -# include +#ifdef HAVE_CYGWIN +#include +#include +#define is_winnt (GetVersion() < 0x80000000) #endif /* AIX limits */ @@ -52,8 +88,8 @@ RCSID("$OpenBSD: session.c,v 1.29 2000/08/21 16:23:31 millert Exp $"); # define S_UNOFILE_HARD S_UNOFILE "_hard" #endif -#ifdef HAVE_LOGIN_CAP -#include +#ifdef _AIX +# include #endif /* types */ @@ -63,7 +99,6 @@ typedef struct Session Session; struct Session { int used; int self; - int extended; struct passwd *pw; pid_t pid; /* tty */ @@ -79,43 +114,48 @@ struct Session { int single_connection; /* proto 2 */ int chanid; + int is_subsystem; }; /* func */ Session *session_new(void); void session_set_fds(Session *s, int fdin, int fdout, int fderr); -void session_pty_cleanup(Session *s); +void session_pty_cleanup(void *session); +int session_pty_req(Session *s); void session_proctitle(Session *s); -void do_exec_pty(Session *s, const char *command, struct passwd * pw); -void do_exec_no_pty(Session *s, const char *command, struct passwd * pw); -void do_login(Session *s); +int session_setup_x11fwd(Session *s); +void session_close(Session *s); +void do_exec_pty(Session *s, const char *command); +void do_exec_no_pty(Session *s, const char *command); +void do_exec(Session *s, const char *command); +void do_login(Session *s, const char *command); +#ifdef LOGIN_NEEDS_UTMPX +void do_pre_login(Session *s); +#endif +void do_child(Session *s, const char *command); +void do_motd(void); +int check_quietlogin(Session *s, const char *command); -void -do_child(const char *command, struct passwd * pw, const char *term, - const char *display, const char *auth_proto, - const char *auth_data, const char *ttyname); +void do_authenticated1(Authctxt *authctxt); +void do_authenticated2(Authctxt *authctxt); /* import */ extern ServerOptions options; -#ifdef HAVE___PROGNAME extern char *__progname; -#else /* HAVE___PROGNAME */ -static const char *__progname = "sshd"; -#endif /* HAVE___PROGNAME */ - extern int log_stderr; extern int debug_flag; -extern unsigned int utmp_len; - +extern u_int utmp_len; extern int startup_pipe; +extern void destroy_sensitive_data(void); -/* Local Xauthority file. */ -static char *xauthfile; +/* original command from peer. */ +const char *original_command = NULL; /* data */ #define MAX_SESSIONS 10 Session sessions[MAX_SESSIONS]; + #ifdef WITH_AIXAUTHENTICATE /* AIX's lastlogin message, set in auth1.c */ char *aixloginmsg; @@ -125,46 +165,42 @@ char *aixloginmsg; static login_cap_t *lc; #endif -/* - * Remove local Xauthority file. - */ void -xauthfile_cleanup_proc(void *ignore) +do_authenticated(Authctxt *authctxt) { - debug("xauthfile_cleanup_proc called"); - - if (xauthfile != NULL) { - char *p; - unlink(xauthfile); - p = strrchr(xauthfile, '/'); - if (p != NULL) { - *p = '\0'; - rmdir(xauthfile); - } - xfree(xauthfile); - xauthfile = NULL; + /* + * Cancel the alarm we set to limit the time taken for + * authentication. + */ + alarm(0); + if (startup_pipe != -1) { + close(startup_pipe); + startup_pipe = -1; } -} - -/* - * Function to perform cleanup if we get aborted abnormally (e.g., due to a - * dropped connection). - */ -void -pty_cleanup_proc(void *session) -{ - Session *s=session; - if (s == NULL) - fatal("pty_cleanup_proc: no session"); - debug("pty_cleanup_proc: %s", s->tty); - - if (s->pid != 0) { - /* Record that the user has logged out. */ - record_logout(s->pid, s->tty); +#if defined(HAVE_LOGIN_CAP) && defined(HAVE_PW_CLASS_IN_PASSWD) + if ((lc = login_getclass(authctxt->pw->pw_class)) == NULL) { + error("unable to get login class"); + return; + } +#ifdef BSD_AUTH + if (auth_approval(NULL, lc, authctxt->pw->pw_name, "ssh") <= 0) { + packet_disconnect("Approval failure for %s", + authctxt->pw->pw_name); } +#endif +#endif + /* setup the channel layer */ + if (!no_port_forwarding_flag && options.allow_tcp_forwarding) + channel_permit_all_opens(); - /* Release the pseudo-tty. */ - pty_release(s->tty); + if (compat20) + do_authenticated2(authctxt); + else + do_authenticated1(authctxt); + + /* remove agent socket */ + if (auth_get_socket_name()) + auth_sock_cleanup_proc(authctxt->pw); } /* @@ -174,53 +210,23 @@ pty_cleanup_proc(void *session) * are requested, etc. */ void -do_authenticated(struct passwd * pw) +do_authenticated1(Authctxt *authctxt) { Session *s; - int type; - int compression_level = 0, enable_compression_after_reply = 0; - int have_pty = 0; char *command; - int n_bytes; - int plen; - unsigned int proto_len, data_len, dlen; - - /* - * Cancel the alarm we set to limit the time taken for - * authentication. - */ - alarm(0); - if (startup_pipe != -1) { - close(startup_pipe); - startup_pipe = -1; - } - - /* - * Inform the channel mechanism that we are the server side and that - * the client may request to connect to any port at all. (The user - * could do it anyway, and we wouldn\'t know what is permitted except - * by the client telling us, so we can equally well trust the client - * not to request anything bogus.) - */ - if (!no_port_forwarding_flag) - channel_permit_all_opens(); + int success, type, plen, screen_flag; + int compression_level = 0, enable_compression_after_reply = 0; + u_int proto_len, data_len, dlen; s = session_new(); - s->pw = pw; - -#ifdef HAVE_LOGIN_CAP - if ((lc = login_getclass(pw->pw_class)) == NULL) { - error("unable to get login class"); - return; - } -#endif + s->pw = authctxt->pw; /* * We stay in this loop until the client requests to execute a shell * or a command. */ for (;;) { - int success = 0; + success = 0; /* Get a packet from the client. */ type = packet_read(&plen); @@ -241,101 +247,33 @@ do_authenticated(struct passwd * pw) break; case SSH_CMSG_REQUEST_PTY: - if (no_pty_flag) { - debug("Allocating a pty not permitted for this authentication."); - break; - } - if (have_pty) - packet_disconnect("Protocol error: you already have a pty."); - - debug("Allocating pty."); - - /* Allocate a pty and open it. */ - if (!pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, - sizeof(s->tty))) { - error("Failed to allocate pty."); - break; - } - fatal_add_cleanup(pty_cleanup_proc, (void *)s); - pty_setowner(pw, s->tty); - - /* Get TERM from the packet. Note that the value may be of arbitrary length. */ - s->term = packet_get_string(&dlen); - packet_integrity_check(dlen, strlen(s->term), type); - /* packet_integrity_check(plen, 4 + dlen + 4*4 + n_bytes, type); */ - /* Remaining bytes */ - n_bytes = plen - (4 + dlen + 4 * 4); - - if (strcmp(s->term, "") == 0) { - xfree(s->term); - s->term = NULL; - } - /* Get window size from the packet. */ - s->row = packet_get_int(); - s->col = packet_get_int(); - s->xpixel = packet_get_int(); - s->ypixel = packet_get_int(); - pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel); - - /* Get tty modes from the packet. */ - tty_parse_modes(s->ttyfd, &n_bytes); - packet_integrity_check(plen, 4 + dlen + 4 * 4 + n_bytes, type); - - session_proctitle(s); - - /* Indicate that we now have a pty. */ - success = 1; - have_pty = 1; + success = session_pty_req(s); break; case SSH_CMSG_X11_REQUEST_FORWARDING: - if (!options.x11_forwarding) { - packet_send_debug("X11 forwarding disabled in server configuration file."); - break; - } - if (!options.xauth_location) { - packet_send_debug("No xauth program; cannot forward with spoofing."); - break; - } - if (no_x11_forwarding_flag) { - packet_send_debug("X11 forwarding not permitted for this authentication."); - break; - } - debug("Received request for X11 forwarding with auth spoofing."); - if (s->display != NULL) - packet_disconnect("Protocol error: X11 display already set."); - s->auth_proto = packet_get_string(&proto_len); s->auth_data = packet_get_string(&data_len); - packet_integrity_check(plen, 4 + proto_len + 4 + data_len + 4, type); - if (packet_get_protocol_flags() & SSH_PROTOFLAG_SCREEN_NUMBER) + screen_flag = packet_get_protocol_flags() & + SSH_PROTOFLAG_SCREEN_NUMBER; + debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag); + + if (packet_remaining() == 4) { + if (!screen_flag) + debug2("Buggy client: " + "X11 screen flag missing"); s->screen = packet_get_int(); - else + } else { s->screen = 0; - s->display = x11_create_display_inet(s->screen, options.x11_display_offset); - - if (s->display == NULL) - break; - - /* Setup to always have a local .Xauthority. */ - xauthfile = xmalloc(MAXPATHLEN); - strlcpy(xauthfile, "/tmp/ssh-XXXXXXXX", MAXPATHLEN); - temporarily_use_uid(pw->pw_uid); - if (mkdtemp(xauthfile) == NULL) { - restore_uid(); - error("private X11 dir: mkdtemp %s failed: %s", - xauthfile, strerror(errno)); - xfree(xauthfile); - xauthfile = NULL; - /* XXXX remove listening channels */ - break; } - strlcat(xauthfile, "/cookies", MAXPATHLEN); - open(xauthfile, O_RDWR|O_CREAT|O_EXCL, 0600); - restore_uid(); - fatal_add_cleanup(xauthfile_cleanup_proc, NULL); - success = 1; + packet_done(); + success = session_setup_x11fwd(s); + if (!success) { + xfree(s->auth_proto); + xfree(s->auth_data); + s->auth_proto = NULL; + s->auth_data = NULL; + } break; case SSH_CMSG_AGENT_REQUEST_FORWARDING: @@ -344,7 +282,7 @@ do_authenticated(struct passwd * pw) break; } debug("Received authentication agent forwarding request."); - success = auth_input_request_forwarding(pw); + success = auth_input_request_forwarding(s->pw); break; case SSH_CMSG_PORT_FORWARD_REQUEST: @@ -352,8 +290,12 @@ do_authenticated(struct passwd * pw) debug("Port forwarding not permitted for this authentication."); break; } + if (!options.allow_tcp_forwarding) { + debug("Port forwarding not permitted."); + break; + } debug("Received TCP/IP port forwarding request."); - channel_input_port_forward_request(pw->pw_uid == 0, options.gateway_ports); + channel_input_port_forward_request(s->pw->pw_uid == 0, options.gateway_ports); success = 1; break; @@ -364,32 +306,16 @@ do_authenticated(struct passwd * pw) case SSH_CMSG_EXEC_SHELL: case SSH_CMSG_EXEC_CMD: - /* Set interactive/non-interactive mode. */ - packet_set_interactive(have_pty || s->display != NULL, - options.keepalives); - if (type == SSH_CMSG_EXEC_CMD) { command = packet_get_string(&dlen); debug("Exec command '%.500s'", command); - packet_integrity_check(plen, 4 + dlen, type); + do_exec(s, command); + xfree(command); } else { - command = NULL; - packet_integrity_check(plen, 0, type); - } - if (forced_command != NULL) { - command = forced_command; - debug("Forced command '%.500s'", forced_command); + do_exec(s, NULL); } - if (have_pty) - do_exec_pty(s, command, pw); - else - do_exec_no_pty(s, command, pw); - - if (command != NULL) - xfree(command); - /* Cleanup user's local Xauthority file. */ - if (xauthfile) - xauthfile_cleanup_proc(NULL); + packet_done(); + session_close(s); return; default: @@ -417,7 +343,7 @@ do_authenticated(struct passwd * pw) * setting up file descriptors and such. */ void -do_exec_no_pty(Session *s, const char *command, struct passwd * pw) +do_exec_no_pty(Session *s, const char *command) { int pid; @@ -440,8 +366,8 @@ do_exec_no_pty(Session *s, const char *command, struct passwd * pw) session_proctitle(s); -#ifdef USE_PAM - do_pam_setcred(); +#if defined(USE_PAM) + do_pam_setcred(1); #endif /* USE_PAM */ /* Fork the child. */ @@ -494,12 +420,18 @@ do_exec_no_pty(Session *s, const char *command, struct passwd * pw) #endif /* USE_PIPES */ /* Do processing for the child (exec command etc). */ - do_child(command, pw, NULL, s->display, s->auth_proto, s->auth_data, NULL); + do_child(s, command); /* NOTREACHED */ } +#ifdef HAVE_CYGWIN + if (is_winnt) + cygwin_set_impersonation_token(INVALID_HANDLE_VALUE); +#endif if (pid < 0) packet_disconnect("fork failed: %.100s", strerror(errno)); s->pid = pid; + /* Set interactive/non-interactive mode. */ + packet_set_interactive(s->display != NULL); #ifdef USE_PIPES /* We are the parent. Close the child sides of the pipes. */ close(pin[0]); @@ -507,11 +439,11 @@ do_exec_no_pty(Session *s, const char *command, struct passwd * pw) close(perr[1]); if (compat20) { - session_set_fds(s, pin[1], pout[0], s->extended ? perr[0] : -1); + session_set_fds(s, pin[1], pout[0], s->is_subsystem ? -1 : perr[0]); } else { /* Enter the interactive session. */ server_loop(pid, pin[1], pout[0], perr[0]); - /* server_loop has closed pin[1], pout[1], and perr[1]. */ + /* server_loop has closed pin[1], pout[0], and perr[0]. */ } #else /* USE_PIPES */ /* We are the parent. Close the child sides of the socket pairs. */ @@ -523,7 +455,7 @@ do_exec_no_pty(Session *s, const char *command, struct passwd * pw) * handle the case that fdin and fdout are the same. */ if (compat20) { - session_set_fds(s, inout[1], inout[1], s->extended ? err[1] : -1); + session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]); } else { server_loop(pid, inout[1], inout[1], err[1]); /* server_loop has closed inout[1] and err[1]. */ @@ -538,7 +470,7 @@ do_exec_no_pty(Session *s, const char *command, struct passwd * pw) * lastlog, and other such operations. */ void -do_exec_pty(Session *s, const char *command, struct passwd * pw) +do_exec_pty(Session *s, const char *command) { int fdout, ptyfd, ttyfd, ptymaster; pid_t pid; @@ -548,10 +480,10 @@ do_exec_pty(Session *s, const char *command, struct passwd * pw) ptyfd = s->ptyfd; ttyfd = s->ttyfd; -#ifdef USE_PAM - do_pam_session(pw->pw_name, s->tty); - do_pam_setcred(); -#endif /* USE_PAM */ +#if defined(USE_PAM) + do_pam_session(s->pw->pw_name, s->tty); + do_pam_setcred(1); +#endif /* Fork the child. */ if ((pid = fork()) == 0) { @@ -580,14 +512,23 @@ do_exec_pty(Session *s, const char *command, struct passwd * pw) close(ttyfd); /* record login, etc. similar to login(1) */ - if (command == NULL && !options.use_login) - do_login(s); +#ifndef HAVE_OSF_SIA + if (!(options.use_login && command == NULL)) + do_login(s, command); +# ifdef LOGIN_NEEDS_UTMPX + else + do_pre_login(s); +# endif +#endif /* Do common processing for the child, such as execing the command. */ - do_child(command, pw, s->term, s->display, s->auth_proto, - s->auth_data, s->tty); + do_child(s, command); /* NOTREACHED */ } +#ifdef HAVE_CYGWIN + if (is_winnt) + cygwin_set_impersonation_token(INVALID_HANDLE_VALUE); +#endif if (pid < 0) packet_disconnect("fork failed: %.100s", strerror(errno)); s->pid = pid; @@ -611,36 +552,74 @@ do_exec_pty(Session *s, const char *command, struct passwd * pw) s->ptymaster = ptymaster; /* Enter interactive session. */ + packet_set_interactive(1); if (compat20) { session_set_fds(s, ptyfd, fdout, -1); } else { server_loop(pid, ptyfd, fdout, -1); /* server_loop _has_ closed ptyfd and fdout. */ - session_pty_cleanup(s); } } -const char * -get_remote_name_or_ip(void) +#ifdef LOGIN_NEEDS_UTMPX +void +do_pre_login(Session *s) +{ + socklen_t fromlen; + struct sockaddr_storage from; + pid_t pid = getpid(); + + /* + * Get IP address of client. If the connection is not a socket, let + * the address be 0.0.0.0. + */ + memset(&from, 0, sizeof(from)); + if (packet_connection_is_on_socket()) { + fromlen = sizeof(from); + if (getpeername(packet_get_connection_in(), + (struct sockaddr *) & from, &fromlen) < 0) { + debug("getpeername: %.100s", strerror(errno)); + fatal_cleanup(); + } + } + + record_utmp_only(pid, s->tty, s->pw->pw_name, + get_remote_name_or_ip(utmp_len, options.reverse_mapping_check), + (struct sockaddr *)&from); +} +#endif + +/* + * This is called to fork and execute a command. If another command is + * to be forced, execute that instead. + */ +void +do_exec(Session *s, const char *command) { - static const char *remote = ""; - if (utmp_len > 0) - remote = get_canonical_hostname(); - if (utmp_len == 0 || strlen(remote) > utmp_len) - remote = get_remote_ipaddr(); - return remote; + if (forced_command) { + original_command = command; + command = forced_command; + forced_command = NULL; + debug("Forced command '%.900s'", command); + } + + if (s->ttyfd != -1) + do_exec_pty(s, command); + else + do_exec_no_pty(s, command); + + original_command = NULL; } + /* administrative, login(1)-like work */ void -do_login(Session *s) +do_login(Session *s, const char *command) { - FILE *f; char *time_string; - char buf[256]; + char hostname[MAXHOSTNAMELEN]; socklen_t fromlen; struct sockaddr_storage from; - struct stat st; time_t last_login_time; struct passwd * pw = s->pw; pid_t pid = getpid(); @@ -659,42 +638,63 @@ do_login(Session *s) } } + /* Get the time and hostname when the user last logged in. */ + if (options.print_lastlog) { + hostname[0] = '\0'; + last_login_time = get_last_login_time(pw->pw_uid, pw->pw_name, + hostname, sizeof(hostname)); + } + /* Record that there was a login on that tty from the remote host. */ record_login(pid, s->tty, pw->pw_name, pw->pw_uid, - get_remote_name_or_ip(), (struct sockaddr *)&from); + get_remote_name_or_ip(utmp_len, options.reverse_mapping_check), + (struct sockaddr *)&from); - /* Done if .hushlogin exists. */ - snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir); -#ifdef HAVE_LOGIN_CAP - if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0) -#else - if (stat(buf, &st) >= 0) +#ifdef USE_PAM + /* + * If password change is needed, do it now. + * This needs to occur before the ~/.hushlogin check. + */ + if (is_pam_password_change_required()) { + print_pam_messages(); + do_pam_chauthtok(); + } #endif + + if (check_quietlogin(s, command)) return; #ifdef USE_PAM - print_pam_messages(); + if (!is_pam_password_change_required()) + print_pam_messages(); #endif /* USE_PAM */ #ifdef WITH_AIXAUTHENTICATE if (aixloginmsg && *aixloginmsg) printf("%s\n", aixloginmsg); #endif /* WITH_AIXAUTHENTICATE */ - /* - * Get the time when the user last logged in. 'buf' will be set - * to contain the hostname the last login was from. - */ - last_login_time = get_last_login_time(pw->pw_uid, pw->pw_name, - buf, sizeof(buf)); - if (last_login_time != 0) { + if (options.print_lastlog && last_login_time != 0) { time_string = ctime(&last_login_time); if (strchr(time_string, '\n')) *strchr(time_string, '\n') = 0; - if (strcmp(buf, "") == 0) + if (strcmp(hostname, "") == 0) printf("Last login: %s\r\n", time_string); else - printf("Last login: %s from %s\r\n", time_string, buf); + printf("Last login: %s from %s\r\n", time_string, hostname); } + + do_motd(); +} + +/* + * Display the message of the day. + */ +void +do_motd(void) +{ + FILE *f; + char buf[256]; + if (options.print_motd) { #ifdef HAVE_LOGIN_CAP f = fopen(login_getcapstr(lc, "welcome", "/etc/motd", @@ -710,15 +710,40 @@ do_login(Session *s) } } + +/* + * Check for quiet login, either .hushlogin or command given. + */ +int +check_quietlogin(Session *s, const char *command) +{ + char buf[256]; + struct passwd * pw = s->pw; + struct stat st; + + /* Return 1 if .hushlogin exists or a command given. */ + if (command != NULL) + return 1; + snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir); +#ifdef HAVE_LOGIN_CAP + if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0) + return 1; +#else + if (stat(buf, &st) >= 0) + return 1; +#endif + return 0; +} + /* * Sets the value of the given variable in the environment. If the variable * already exists, its value is overriden. */ void -child_set_env(char ***envp, unsigned int *envsizep, const char *name, +child_set_env(char ***envp, u_int *envsizep, const char *name, const char *value) { - unsigned int i, namelen; + u_int i, namelen; char **env; /* @@ -756,7 +781,7 @@ child_set_env(char ***envp, unsigned int *envsizep, const char *name, * and assignments of the form name=value. No other forms are allowed. */ void -read_environment_file(char ***env, unsigned int *envsize, +read_environment_file(char ***env, u_int *envsize, const char *filename) { FILE *f; @@ -802,11 +827,11 @@ void do_pam_environment(char ***env, int *envsize) if ((pam_env = fetch_pam_environment()) == NULL) return; - + for(i = 0; pam_env[i] != NULL; i++) { if ((equals = strstr(pam_env[i], "=")) == NULL) continue; - + if (strlen(pam_env[i]) < (sizeof(var_name) - 1)) { memset(var_name, '\0', sizeof(var_name)); memset(var_val, '\0', sizeof(var_val)); @@ -814,7 +839,7 @@ void do_pam_environment(char ***env, int *envsize) strncpy(var_name, pam_env[i], equals - pam_env[i]); strcpy(var_val, equals + 1); - debug("PAM environment: %s=%s", var_name, var_val); + debug3("PAM environment: %s=%s", var_name, var_val); child_set_env(env, envsize, var_name, var_val); } @@ -822,6 +847,31 @@ void do_pam_environment(char ***env, int *envsize) } #endif /* USE_PAM */ +#ifdef HAVE_CYGWIN +void copy_environment(char ***env, int *envsize) +{ + char *equals, var_name[512], var_val[512]; + int i; + + for(i = 0; environ[i] != NULL; i++) { + if ((equals = strstr(environ[i], "=")) == NULL) + continue; + + if (strlen(environ[i]) < (sizeof(var_name) - 1)) { + memset(var_name, '\0', sizeof(var_name)); + memset(var_val, '\0', sizeof(var_val)); + + strncpy(var_name, environ[i], equals - environ[i]); + strcpy(var_val, equals + 1); + + debug3("Copy environment: %s=%s", var_name, var_val); + + child_set_env(env, envsize, var_name, var_val); + } + } +} +#endif + #if defined(HAVE_GETUSERATTR) /* * AIX-specific login initialisation @@ -907,28 +957,41 @@ void set_limits_from_userattr(char *user) * ids, and executing the command or shell. */ void -do_child(const char *command, struct passwd * pw, const char *term, - const char *display, const char *auth_proto, - const char *auth_data, const char *ttyname) +do_child(Session *s, const char *command) { - const char *shell, *hostname, *cp = NULL; + const char *shell, *hostname = NULL, *cp = NULL; + struct passwd * pw = s->pw; char buf[256]; char cmd[1024]; FILE *f = NULL; - unsigned int envsize, i; + u_int envsize, i; char **env; extern char **environ; struct stat st; char *argv[10]; + int do_xauth; #ifdef WITH_IRIX_PROJECT prid_t projid; #endif /* WITH_IRIX_PROJECT */ +#ifdef WITH_IRIX_JOBS + jid_t jid = 0; +#else +#ifdef WITH_IRIX_ARRAY + int jid = 0; +#endif /* WITH_IRIX_ARRAY */ +#endif /* WITH_IRIX_JOBS */ + + do_xauth = + s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL; + + /* remove hostkey from the child's memory */ + destroy_sensitive_data(); /* login(1) is only called if we execute the login shell */ if (options.use_login && command != NULL) options.use_login = 0; -#ifndef USE_PAM /* pam_nologin handles this */ +#if !defined(USE_PAM) && !defined(HAVE_OSF_SIA) if (!options.use_login) { # ifdef HAVE_LOGIN_CAP if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid) @@ -946,29 +1009,22 @@ do_child(const char *command, struct passwd * pw, const char *term, exit(254); } } -#endif /* USE_PAM */ +#endif /* USE_PAM || HAVE_OSF_SIA */ /* Set login name, uid, gid, and groups. */ /* Login(1) does this as well, and it needs uid 0 for the "-h" switch, so we let login(1) to this for us. */ if (!options.use_login) { #ifdef HAVE_OSF_SIA - extern char **saved_argv; - extern int saved_argc; - char *host = get_canonical_hostname (); - - if (sia_become_user(NULL, saved_argc, saved_argv, host, - pw->pw_name, ttyname, 0, NULL, NULL, SIA_BEU_SETLUID) != - SIASUCCESS) { - perror("sia_become_user"); - exit(1); - } - if (setreuid(geteuid(), geteuid()) < 0) { - perror("setreuid"); - exit(1); - } + session_setup_sia(pw->pw_name, s->ttyfd == -1 ? NULL : s->tty); + if (!check_quietlogin(s, command)) + do_motd(); #else /* HAVE_OSF_SIA */ +#ifdef HAVE_CYGWIN + if (is_winnt) { +#else if (getuid() == 0 || geteuid() == 0) { +#endif # ifdef HAVE_GETUSERATTR set_limits_from_userattr(pw->pw_name); # endif /* HAVE_GETUSERATTR */ @@ -979,6 +1035,12 @@ do_child(const char *command, struct passwd * pw, const char *term, exit(1); } # else /* HAVE_LOGIN_CAP */ +#if defined(HAVE_GETLUID) && defined(HAVE_SETLUID) + /* Sets login uid for accounting */ + if (getluid() == -1 && setluid(pw->pw_uid) == -1) + error("setluid: %s", strerror(errno)); +#endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */ + if (setlogin(pw->pw_name) < 0) error("setlogin failed: %s", strerror(errno)); if (setgid(pw->pw_gid) < 0) { @@ -991,11 +1053,29 @@ do_child(const char *command, struct passwd * pw, const char *term, exit(1); } endgrent(); +# ifdef USE_PAM + /* + * PAM credentials may take the form of + * supplementary groups. These will have been + * wiped by the above initgroups() call. + * Reestablish them here. + */ + do_pam_setcred(0); +# endif /* USE_PAM */ +# ifdef WITH_IRIX_JOBS + jid = jlimit_startjob(pw->pw_name, pw->pw_uid, "interactive"); + if (jid == -1) { + fatal("Failed to create job container: %.100s", + strerror(errno)); + } +# endif /* WITH_IRIX_JOBS */ # ifdef WITH_IRIX_ARRAY /* initialize array session */ - if (newarraysess() != 0) - fatal("Failed to set up new array session: %.100s", - strerror(errno)); + if (jid == 0) { + if (newarraysess() != 0) + fatal("Failed to set up new array session: %.100s", + strerror(errno)); + } # endif /* WITH_IRIX_ARRAY */ # ifdef WITH_IRIX_PROJECT /* initialize irix project info */ @@ -1007,14 +1087,44 @@ do_child(const char *command, struct passwd * pw, const char *term, fatal("Failed to initialize project %d for %s: %.100s", (int)projid, pw->pw_name, strerror(errno)); # endif /* WITH_IRIX_PROJECT */ +#ifdef WITH_IRIX_AUDIT + if (sysconf(_SC_AUDIT)) { + debug("Setting sat id to %d", (int) pw->pw_uid); + if (satsetid(pw->pw_uid)) + debug("error setting satid: %.100s", strerror(errno)); + } +#endif /* WITH_IRIX_AUDIT */ + +#ifdef _AIX + /* + * AIX has a "usrinfo" area where logname and + * other stuff is stored - a few applications + * actually use this and die if it's not set + */ + if (s->ttyfd == -1) + s->tty[0] = '\0'; + cp = xmalloc(22 + strlen(s->tty) + + 2 * strlen(pw->pw_name)); + i = sprintf(cp, "LOGNAME=%s%cNAME=%s%cTTY=%s%c%c", + pw->pw_name, 0, pw->pw_name, 0, s->tty, 0, 0); + if (usrinfo(SETUINFO, cp, i) == -1) + fatal("Couldn't set usrinfo: %s", + strerror(errno)); + debug3("AIX/UsrInfo: set len %d", i); + xfree(cp); +#endif + /* Permanently switch to the desired uid. */ - permanently_set_uid(pw->pw_uid); + permanently_set_uid(pw); # endif /* HAVE_LOGIN_CAP */ } #endif /* HAVE_OSF_SIA */ +#ifdef HAVE_CYGWIN + if (is_winnt) +#endif if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid) - fatal("Failed to set uids to %d.", (int) pw->pw_uid); + fatal("Failed to set uids to %u.", (u_int) pw->pw_uid); } /* * Get the shell from the password data. An empty shell field is @@ -1042,6 +1152,14 @@ do_child(const char *command, struct passwd * pw, const char *term, env = xmalloc(envsize * sizeof(char *)); env[0] = NULL; +#ifdef HAVE_CYGWIN + /* + * The Windows environment contains some setting which are + * important for a running system. They must not be dropped. + */ + copy_environment(&env, &envsize); +#endif + if (!options.use_login) { /* Set basic environment. */ child_set_env(&env, &envsize, "USER", pw->pw_name); @@ -1050,9 +1168,17 @@ do_child(const char *command, struct passwd * pw, const char *term, #ifdef HAVE_LOGIN_CAP (void) setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH); child_set_env(&env, &envsize, "PATH", getenv("PATH")); -#else +#else /* HAVE_LOGIN_CAP */ +# ifndef HAVE_CYGWIN + /* + * There's no standard path on Windows. The path contains + * important components pointing to the system directories, + * needed for loading shared libraries. So the path better + * remains intact here. + */ child_set_env(&env, &envsize, "PATH", _PATH_STDPATH); -#endif +# endif /* HAVE_CYGWIN */ +#endif /* HAVE_LOGIN_CAP */ snprintf(buf, sizeof buf, "%.200s/%.50s", _PATH_MAILDIR, pw->pw_name); @@ -1083,23 +1209,22 @@ do_child(const char *command, struct passwd * pw, const char *term, get_remote_ipaddr(), get_remote_port(), get_local_port()); child_set_env(&env, &envsize, "SSH_CLIENT", buf); - if (ttyname) - child_set_env(&env, &envsize, "SSH_TTY", ttyname); - if (term) - child_set_env(&env, &envsize, "TERM", term); - if (display) - child_set_env(&env, &envsize, "DISPLAY", display); + if (s->ttyfd != -1) + child_set_env(&env, &envsize, "SSH_TTY", s->tty); + if (s->term) + child_set_env(&env, &envsize, "TERM", s->term); + if (s->display) + child_set_env(&env, &envsize, "DISPLAY", s->display); + if (original_command) + child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND", + original_command); #ifdef _AIX - { - char *authstate,*krb5cc; - - if ((authstate = getenv("AUTHSTATE")) != NULL) - child_set_env(&env,&envsize,"AUTHSTATE",authstate); - - if ((krb5cc = getenv("KRB5CCNAME")) != NULL) - child_set_env(&env,&envsize,"KRB5CCNAME",krb5cc); - } + if ((cp = getenv("AUTHSTATE")) != NULL) + child_set_env(&env, &envsize, "AUTHSTATE", cp); + if ((cp = getenv("KRB5CCNAME")) != NULL) + child_set_env(&env, &envsize, "KRB5CCNAME", cp); + read_environment_file(&env, &envsize, "/etc/environment"); #endif #ifdef KRB4 @@ -1116,10 +1241,6 @@ do_child(const char *command, struct passwd * pw, const char *term, do_pam_environment(&env, &envsize); #endif /* USE_PAM */ - read_environment_file(&env,&envsize,"/etc/environment"); - - if (xauthfile) - child_set_env(&env, &envsize, "XAUTHORITY", xauthfile); if (auth_get_socket_name() != NULL) child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME, auth_get_socket_name()); @@ -1138,7 +1259,8 @@ do_child(const char *command, struct passwd * pw, const char *term, } /* we have to stash the hostname before we close our socket. */ if (options.use_login) - hostname = get_remote_name_or_ip(); + hostname = get_remote_name_or_ip(utmp_len, + options.reverse_mapping_check); /* * Close the connection descriptors; note that this is the child, and * the server will still have the socket open, and it is important @@ -1195,58 +1317,67 @@ do_child(const char *command, struct passwd * pw, const char *term, * in this order). */ if (!options.use_login) { - if (stat(SSH_USER_RC, &st) >= 0) { + /* ignore _PATH_SSH_USER_RC for subsystems */ + if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) { + snprintf(cmd, sizeof cmd, "%s -c '%s %s'", + shell, _PATH_BSHELL, _PATH_SSH_USER_RC); if (debug_flag) - fprintf(stderr, "Running "_PATH_BSHELL" %s\n", SSH_USER_RC); - - f = popen(_PATH_BSHELL " " SSH_USER_RC, "w"); + fprintf(stderr, "Running %s\n", cmd); + f = popen(cmd, "w"); if (f) { - if (auth_proto != NULL && auth_data != NULL) - fprintf(f, "%s %s\n", auth_proto, auth_data); + if (do_xauth) + fprintf(f, "%s %s\n", s->auth_proto, + s->auth_data); pclose(f); } else - fprintf(stderr, "Could not run %s\n", SSH_USER_RC); - } else if (stat(SSH_SYSTEM_RC, &st) >= 0) { + fprintf(stderr, "Could not run %s\n", + _PATH_SSH_USER_RC); + } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) { if (debug_flag) - fprintf(stderr, "Running "_PATH_BSHELL" %s\n", SSH_SYSTEM_RC); - - f = popen(_PATH_BSHELL " " SSH_SYSTEM_RC, "w"); + fprintf(stderr, "Running %s %s\n", _PATH_BSHELL, + _PATH_SSH_SYSTEM_RC); + f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w"); if (f) { - if (auth_proto != NULL && auth_data != NULL) - fprintf(f, "%s %s\n", auth_proto, auth_data); + if (do_xauth) + fprintf(f, "%s %s\n", s->auth_proto, + s->auth_data); pclose(f); } else - fprintf(stderr, "Could not run %s\n", SSH_SYSTEM_RC); - } else if (options.xauth_location != NULL) { + fprintf(stderr, "Could not run %s\n", + _PATH_SSH_SYSTEM_RC); + } else if (do_xauth && options.xauth_location != NULL) { /* Add authority data to .Xauthority if appropriate. */ - if (auth_proto != NULL && auth_data != NULL) { - char *screen = strchr(display, ':'); - if (debug_flag) { + char *screen = strchr(s->display, ':'); + + if (debug_flag) { + fprintf(stderr, + "Running %.100s add " + "%.100s %.100s %.100s\n", + options.xauth_location, s->display, + s->auth_proto, s->auth_data); + if (screen != NULL) fprintf(stderr, - "Running %.100s add %.100s %.100s %.100s\n", - options.xauth_location, display, - auth_proto, auth_data); - if (screen != NULL) - fprintf(stderr, - "Adding %.*s/unix%s %s %s\n", - screen-display, display, - screen, auth_proto, auth_data); - } - snprintf(cmd, sizeof cmd, "%s -q -", - options.xauth_location); - f = popen(cmd, "w"); - if (f) { - fprintf(f, "add %s %s %s\n", display, - auth_proto, auth_data); - if (screen != NULL) - fprintf(f, "add %.*s/unix%s %s %s\n", - screen-display, display, - screen, auth_proto, auth_data); - pclose(f); - } else { - fprintf(stderr, "Could not run %s\n", - cmd); - } + "Adding %.*s/unix%s %s %s\n", + (int)(screen - s->display), + s->display, screen, + s->auth_proto, s->auth_data); + } + snprintf(cmd, sizeof cmd, "%s -q -", + options.xauth_location); + f = popen(cmd, "w"); + if (f) { + fprintf(f, "add %s %s %s\n", s->display, + s->auth_proto, s->auth_data); + if (screen != NULL) + fprintf(f, "add %.*s/unix%s %s %s\n", + (int)(screen - s->display), + s->display, screen, + s->auth_proto, + s->auth_data); + pclose(f); + } else { + fprintf(stderr, "Could not run %s\n", + cmd); } } /* Get the last component of the shell name. */ @@ -1256,6 +1387,10 @@ do_child(const char *command, struct passwd * pw, const char *term, else cp = shell; } + + /* restore SIGPIPE for child */ + signal(SIGPIPE, SIG_DFL); + /* * If we have no command, execute the shell. In this case, the shell * name to be passed in argv[0] is preceded by '-' to indicate that @@ -1269,9 +1404,10 @@ do_child(const char *command, struct passwd * pw, const char *term, * Check for mail if we have a tty and it was enabled * in server options. */ - if (ttyname && options.check_mail) { + if (s->ttyfd != -1 && options.check_mail) { char *mailbox; struct stat mailstat; + mailbox = getenv("MAIL"); if (mailbox != NULL) { if (stat(mailbox, &mailstat) != 0 || @@ -1301,6 +1437,9 @@ do_child(const char *command, struct passwd * pw, const char *term, /* Launch login(1). */ execl(LOGIN_PROGRAM, "login", "-h", hostname, +#ifdef LOGIN_NEEDS_TERM + s->term? s->term : "unknown", +#endif "-p", "-f", "--", pw->pw_name, NULL); /* Login couldn't be executed, die. */ @@ -1331,26 +1470,18 @@ session_new(void) debug("session_new: init"); for(i = 0; i < MAX_SESSIONS; i++) { sessions[i].used = 0; - sessions[i].self = i; } did_init = 1; } for(i = 0; i < MAX_SESSIONS; i++) { Session *s = &sessions[i]; if (! s->used) { - s->pid = 0; - s->extended = 0; + memset(s, 0, sizeof(*s)); s->chanid = -1; s->ptyfd = -1; s->ttyfd = -1; - s->term = NULL; - s->pw = NULL; - s->display = NULL; - s->screen = 0; - s->auth_data = NULL; - s->auth_proto = NULL; s->used = 1; - s->pw = NULL; + s->self = i; debug("session_new: session %d", i); return s; } @@ -1384,7 +1515,7 @@ session_open(int chanid) } s->pw = auth_get_user(); if (s->pw == NULL) - fatal("no user for session %i", s->self); + fatal("no user for session %d", s->self); debug("session_open: session %d: link with channel %d", s->self, chanid); s->chanid = chanid; return 1; @@ -1436,56 +1567,72 @@ session_window_change_req(Session *s) int session_pty_req(Session *s) { - unsigned int len; - char *term_modes; /* encoded terminal modes */ + u_int len; + int n_bytes; - if (no_pty_flag) + if (no_pty_flag) { + debug("Allocating a pty not permitted for this authentication."); return 0; - if (s->ttyfd != -1) + } + if (s->ttyfd != -1) { + packet_disconnect("Protocol error: you already have a pty."); return 0; + } + s->term = packet_get_string(&len); - s->col = packet_get_int(); - s->row = packet_get_int(); + + if (compat20) { + s->col = packet_get_int(); + s->row = packet_get_int(); + } else { + s->row = packet_get_int(); + s->col = packet_get_int(); + } s->xpixel = packet_get_int(); s->ypixel = packet_get_int(); - term_modes = packet_get_string(&len); - packet_done(); if (strcmp(s->term, "") == 0) { xfree(s->term); s->term = NULL; } + /* Allocate a pty and open it. */ + debug("Allocating pty."); if (!pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty))) { - xfree(s->term); + if (s->term) + xfree(s->term); s->term = NULL; s->ptyfd = -1; s->ttyfd = -1; error("session_pty_req: session %d alloc failed", s->self); - xfree(term_modes); return 0; } debug("session_pty_req: session %d alloc %s", s->self, s->tty); + + /* for SSH1 the tty modes length is not given */ + if (!compat20) + n_bytes = packet_remaining(); + tty_parse_modes(s->ttyfd, &n_bytes); + /* * Add a cleanup function to clear the utmp entry and record logout * time in case we call fatal() (e.g., the connection gets closed). */ - fatal_add_cleanup(pty_cleanup_proc, (void *)s); + fatal_add_cleanup(session_pty_cleanup, (void *)s); pty_setowner(s->pw, s->tty); - /* Get window size from the packet. */ + + /* Set window size from the packet. */ pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel); + packet_done(); session_proctitle(s); - - /* XXX parse and set terminal modes */ - xfree(term_modes); return 1; } int session_subsystem_req(Session *s) { - unsigned int len; + u_int len; int success = 0; char *subsys = packet_get_string(&len); int i; @@ -1496,7 +1643,8 @@ session_subsystem_req(Session *s) for (i = 0; i < options.num_subsystems; i++) { if(strcmp(subsys, options.subsystem_name[i]) == 0) { debug("subsystem: exec() %s", options.subsystem_command[i]); - do_exec_no_pty(s, options.subsystem_command[i], s->pw); + s->is_subsystem = 1; + do_exec_no_pty(s, options.subsystem_command[i]); success = 1; } } @@ -1511,22 +1659,7 @@ session_subsystem_req(Session *s) int session_x11_req(Session *s) { - if (no_x11_forwarding_flag) { - debug("X11 forwarding disabled in user configuration file."); - return 0; - } - if (!options.x11_forwarding) { - debug("X11 forwarding disabled in server configuration file."); - return 0; - } - if (xauthfile != NULL) { - debug("X11 fwd already started."); - return 0; - } - - debug("Received request for X11 forwarding with auth spoofing."); - if (s->display != NULL) - packet_disconnect("Protocol error: X11 display already set."); + int success; s->single_connection = packet_get_char(); s->auth_proto = packet_get_string(NULL); @@ -1534,72 +1667,56 @@ session_x11_req(Session *s) s->screen = packet_get_int(); packet_done(); - s->display = x11_create_display_inet(s->screen, options.x11_display_offset); - if (s->display == NULL) { - xfree(s->auth_proto); - xfree(s->auth_data); - return 0; - } - xauthfile = xmalloc(MAXPATHLEN); - strlcpy(xauthfile, "/tmp/ssh-XXXXXXXX", MAXPATHLEN); - temporarily_use_uid(s->pw->pw_uid); - if (mkdtemp(xauthfile) == NULL) { - restore_uid(); - error("private X11 dir: mkdtemp %s failed: %s", - xauthfile, strerror(errno)); - xfree(xauthfile); - xauthfile = NULL; + success = session_setup_x11fwd(s); + if (!success) { xfree(s->auth_proto); xfree(s->auth_data); - /* XXXX remove listening channels */ - return 0; + s->auth_proto = NULL; + s->auth_data = NULL; } - strlcat(xauthfile, "/cookies", MAXPATHLEN); - open(xauthfile, O_RDWR|O_CREAT|O_EXCL, 0600); - restore_uid(); - fatal_add_cleanup(xauthfile_cleanup_proc, s); - return 1; + return success; } int session_shell_req(Session *s) { - /* if forced_command == NULL, the shell is execed */ - char *shell = forced_command; packet_done(); - s->extended = 1; - if (s->ttyfd == -1) - do_exec_no_pty(s, shell, s->pw); - else - do_exec_pty(s, shell, s->pw); + do_exec(s, NULL); return 1; } int session_exec_req(Session *s) { - unsigned int len; + u_int len; char *command = packet_get_string(&len); packet_done(); - if (forced_command) { - xfree(command); - command = forced_command; - debug("Forced command '%.500s'", forced_command); - } - s->extended = 1; - if (s->ttyfd == -1) - do_exec_no_pty(s, command, s->pw); - else - do_exec_pty(s, command, s->pw); - if (forced_command == NULL) - xfree(command); + do_exec(s, command); + xfree(command); return 1; } +int +session_auth_agent_req(Session *s) +{ + static int called = 0; + packet_done(); + if (no_agent_forwarding_flag) { + debug("session_auth_agent_req: no_agent_forwarding_flag"); + return 0; + } + if (called) { + return 0; + } else { + called = 1; + return auth_input_request_forwarding(s->pw); + } +} + void session_input_channel_req(int id, void *arg) { - unsigned int len; + u_int len; int reply; int success = 0; char *rtype; @@ -1620,8 +1737,8 @@ session_input_channel_req(int id, void *arg) s->self, id, rtype, reply); /* - * a session is in LARVAL state until a shell - * or programm is executed + * a session is in LARVAL state until a shell, a command + * or a subsystem is executed */ if (c->type == SSH_CHANNEL_LARVAL) { if (strcmp(rtype, "shell") == 0) { @@ -1632,6 +1749,8 @@ session_input_channel_req(int id, void *arg) 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) { + success = session_auth_agent_req(s); } else if (strcmp(rtype, "subsystem") == 0) { success = session_subsystem_req(s); } @@ -1662,22 +1781,31 @@ session_set_fds(Session *s, int fdin, int fdout, int fderr) fatal("no channel for session %d", s->self); channel_set_fds(s->chanid, fdout, fdin, fderr, - fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ); + fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ, + 1); } +/* + * Function to perform pty cleanup. Also called if we get aborted abnormally + * (e.g., due to a dropped connection). + */ void -session_pty_cleanup(Session *s) +session_pty_cleanup(void *session) { - if (s == NULL || s->ttyfd == -1) - return; + Session *s = session; - debug("session_pty_cleanup: session %i release %s", s->self, s->tty); + if (s == NULL) { + error("session_pty_cleanup: no session"); + return; + } + if (s->ttyfd == -1) + return; - /* Cancel the cleanup function. */ - fatal_remove_cleanup(pty_cleanup_proc, (void *)s); + debug("session_pty_cleanup: session %d release %s", s->self, s->tty); /* Record that the user has logged out. */ - record_logout(s->pid, s->tty); + if (s->pid != 0) + record_logout(s->pid, s->tty); /* Release the pseudo-tty. */ pty_release(s->tty); @@ -1699,7 +1827,7 @@ session_exit_message(Session *s, int status) fatal("session_close: no session"); c = channel_lookup(s->chanid); if (c == NULL) - fatal("session_close: session %d: no channel %d", + fatal("session_exit_message: session %d: no channel %d", s->self, s->chanid); debug("session_exit_message: session %d channel %d pid %d", s->self, s->chanid, s->pid); @@ -1741,9 +1869,13 @@ session_exit_message(Session *s, int status) } void -session_free(Session *s) +session_close(Session *s) { - debug("session_free: session %d pid %d", s->self, s->pid); + debug("session_close: session %d pid %d", s->self, s->pid); + if (s->ttyfd != -1) { + fatal_remove_cleanup(session_pty_cleanup, (void *)s); + session_pty_cleanup(s); + } if (s->term) xfree(s->term); if (s->display) @@ -1753,13 +1885,6 @@ session_free(Session *s) if (s->auth_proto) xfree(s->auth_proto); s->used = 0; -} - -void -session_close(Session *s) -{ - session_pty_cleanup(s); - session_free(s); session_proctitle(s); } @@ -1768,7 +1893,7 @@ session_close_by_pid(pid_t pid, int status) { Session *s = session_by_pid(pid); if (s == NULL) { - debug("session_close_by_pid: no session for pid %d", s->pid); + debug("session_close_by_pid: no session for pid %d", pid); return; } if (s->chanid != -1) @@ -1798,8 +1923,6 @@ session_close_by_channel(int id, void *arg) session_close(s); } else { /* notify child, delay session cleanup */ - if (s->pid <= 1) - fatal("session_close_by_channel: Unsafe s->pid = %d", s->pid); if (kill(s->pid, (s->ttyfd == -1) ? SIGTERM : SIGHUP) < 0) error("session_close_by_channel: kill %d: %s", s->pid, strerror(errno)); @@ -1834,28 +1957,43 @@ session_proctitle(Session *s) setproctitle("%s@%s", s->pw->pw_name, session_tty_list()); } -void -do_authenticated2(void) +int +session_setup_x11fwd(Session *s) { - struct passwd *pw; + struct stat st; - /* - * Cancel the alarm we set to limit the time taken for - * authentication. - */ - alarm(0); - if (startup_pipe != -1) { - close(startup_pipe); - startup_pipe = -1; + if (no_x11_forwarding_flag) { + packet_send_debug("X11 forwarding disabled in user configuration file."); + return 0; } -#ifdef HAVE_LOGIN_CAP - pw = auth_get_user(); - if ((lc = login_getclass(pw->pw_class)) == NULL) { - error("unable to get login class"); - return; + if (!options.x11_forwarding) { + debug("X11 forwarding disabled in server configuration file."); + return 0; } -#endif + if (!options.xauth_location || + (stat(options.xauth_location, &st) == -1)) { + packet_send_debug("No xauth program; cannot forward with spoofing."); + return 0; + } + if (options.use_login) { + packet_send_debug("X11 forwarding disabled; " + "not compatible with UseLogin=yes."); + return 0; + } + if (s->display != NULL) { + debug("X11 display already set."); + return 0; + } + s->display = x11_create_display_inet(s->screen, options.x11_display_offset); + if (s->display == NULL) { + debug("x11_create_display_inet failed."); + return 0; + } + return 1; +} + +void +do_authenticated2(Authctxt *authctxt) +{ server_loop2(); - if (xauthfile) - xauthfile_cleanup_proc(NULL); }