]> andersk Git - openssh.git/blobdiff - session.c
- djm@cvs.openbsd.org 2004/05/09 01:19:28
[openssh.git] / session.c
index 5b445f93b17da9ee3db468d72ff68c400b0cf68d..2ecf637f987ac4da3b3ffd00ea4d7d025f80561f 100644 (file)
--- a/session.c
+++ b/session.c
@@ -33,7 +33,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: session.c,v 1.156 2003/05/11 20:30:25 markus Exp $");
+RCSID("$OpenBSD: session.c,v 1.174 2004/05/09 01:19:28 djm Exp $");
 
 #include "ssh.h"
 #include "ssh1.h"
@@ -42,7 +42,7 @@ RCSID("$OpenBSD: session.c,v 1.156 2003/05/11 20:30:25 markus Exp $");
 #include "sshpty.h"
 #include "packet.h"
 #include "buffer.h"
-#include "mpaux.h"
+#include "match.h"
 #include "uidswap.h"
 #include "compat.h"
 #include "channels.h"
@@ -58,17 +58,19 @@ RCSID("$OpenBSD: session.c,v 1.156 2003/05/11 20:30:25 markus Exp $");
 #include "session.h"
 #include "monitor_wrap.h"
 
-#ifdef HAVE_CYGWIN
-#include <windows.h>
-#include <sys/cygwin.h>
-#define is_winnt       (GetVersion() < 0x80000000)
+#if defined(KRB5) && defined(USE_AFS)
+#include <kafs.h>
+#endif
+
+#ifdef GSSAPI
+#include "ssh-gss.h"
 #endif
 
 /* func */
 
 Session *session_new(void);
 void   session_set_fds(Session *, int, int, int);
-void   session_pty_cleanup(void *);
+void   session_pty_cleanup(Session *);
 void   session_proctitle(Session *);
 int    session_setup_x11fwd(Session *);
 void   do_exec_pty(Session *, const char *);
@@ -95,6 +97,7 @@ extern int debug_flag;
 extern u_int utmp_len;
 extern int startup_pipe;
 extern void destroy_sensitive_data(void);
+extern Buffer loginmsg;
 
 /* original command from peer. */
 const char *original_command = NULL;
@@ -103,14 +106,12 @@ const char *original_command = NULL;
 #define MAX_SESSIONS 10
 Session        sessions[MAX_SESSIONS];
 
-#ifdef WITH_AIXAUTHENTICATE
-char *aixloginmsg;
-#endif /* WITH_AIXAUTHENTICATE */
-
 #ifdef HAVE_LOGIN_CAP
 login_cap_t *lc;
 #endif
 
+static int is_child = 0;
+
 /* Name and directory of socket for authentication agent forwarding. */
 static char *auth_sock_name = NULL;
 static char *auth_sock_dir = NULL;
@@ -118,10 +119,8 @@ static char *auth_sock_dir = NULL;
 /* removes the agent forwarding socket */
 
 static void
-auth_sock_cleanup_proc(void *_pw)
+auth_sock_cleanup_proc(struct passwd *pw)
 {
-       struct passwd *pw = _pw;
-
        if (auth_sock_name != NULL) {
                temporarily_use_uid(pw);
                unlink(auth_sock_name);
@@ -149,7 +148,7 @@ auth_input_request_forwarding(struct passwd * pw)
        /* Allocate a buffer for the socket name, and format the name. */
        auth_sock_name = xmalloc(MAXPATHLEN);
        auth_sock_dir = xmalloc(MAXPATHLEN);
-       strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
+       strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN);
 
        /* Create private directory for socket */
        if (mkdtemp(auth_sock_dir) == NULL) {
@@ -165,9 +164,6 @@ auth_input_request_forwarding(struct passwd * pw)
        snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%ld",
                 auth_sock_dir, (long) getpid());
 
-       /* delete agent socket on fatal() */
-       fatal_add_cleanup(auth_sock_cleanup_proc, pw);
-
        /* Create the socket. */
        sock = socket(AF_UNIX, SOCK_STREAM, 0);
        if (sock < 0)
@@ -185,7 +181,7 @@ auth_input_request_forwarding(struct passwd * pw)
        restore_uid();
 
        /* Start listening on the socket. */
-       if (listen(sock, 5) < 0)
+       if (listen(sock, SSH_LISTEN_BACKLOG) < 0)
                packet_disconnect("listen: %.100s", strerror(errno));
 
        /* Allocate a channel for the authentication agent socket. */
@@ -197,6 +193,16 @@ auth_input_request_forwarding(struct passwd * pw)
        return 1;
 }
 
+static void
+display_loginmsg(void)
+{
+       if (buffer_len(&loginmsg) > 0) {
+               buffer_append(&loginmsg, "\0", 1);
+               printf("%s\n", (char *)buffer_ptr(&loginmsg));
+               buffer_clear(&loginmsg);
+       }
+       fflush(stdout);
+}
 
 void
 do_authenticated(Authctxt *authctxt)
@@ -212,7 +218,6 @@ do_authenticated(Authctxt *authctxt)
                close(startup_pipe);
                startup_pipe = -1;
        }
-
        /* setup the channel layer */
        if (!no_port_forwarding_flag && options.allow_tcp_forwarding)
                channel_permit_all_opens();
@@ -222,17 +227,7 @@ do_authenticated(Authctxt *authctxt)
        else
                do_authenticated1(authctxt);
 
-       /* remove agent socket */
-       if (auth_sock_name != NULL)
-               auth_sock_cleanup_proc(authctxt->pw);
-#ifdef KRB4
-       if (options.kerberos_ticket_cleanup)
-               krb4_cleanup_proc(authctxt);
-#endif
-#ifdef KRB5
-       if (options.kerberos_ticket_cleanup)
-               krb5_cleanup_proc(authctxt);
-#endif
+       do_cleanup(authctxt);
 }
 
 /*
@@ -341,58 +336,6 @@ do_authenticated1(Authctxt *authctxt)
                                success = 1;
                        break;
 
-#if defined(AFS) || defined(KRB5)
-               case SSH_CMSG_HAVE_KERBEROS_TGT:
-                       if (!options.kerberos_tgt_passing) {
-                               verbose("Kerberos TGT passing disabled.");
-                       } else {
-                               char *kdata = packet_get_string(&dlen);
-                               packet_check_eom();
-
-                               /* XXX - 0x41, see creds_to_radix version */
-                               if (kdata[0] != 0x41) {
-#ifdef KRB5
-                                       krb5_data tgt;
-                                       tgt.data = kdata;
-                                       tgt.length = dlen;
-
-                                       if (auth_krb5_tgt(s->authctxt, &tgt))
-                                               success = 1;
-                                       else
-                                               verbose("Kerberos v5 TGT refused for %.100s", s->authctxt->user);
-#endif /* KRB5 */
-                               } else {
-#ifdef AFS
-                                       if (auth_krb4_tgt(s->authctxt, kdata))
-                                               success = 1;
-                                       else
-                                               verbose("Kerberos v4 TGT refused for %.100s", s->authctxt->user);
-#endif /* AFS */
-                               }
-                               xfree(kdata);
-                       }
-                       break;
-#endif /* AFS || KRB5 */
-
-#ifdef AFS
-               case SSH_CMSG_HAVE_AFS_TOKEN:
-                       if (!options.afs_token_passing || !k_hasafs()) {
-                               verbose("AFS token passing disabled.");
-                       } else {
-                               /* Accept AFS token. */
-                               char *token = packet_get_string(&dlen);
-                               packet_check_eom();
-
-                               if (auth_afs_token(s->authctxt, token))
-                                       success = 1;
-                               else
-                                       verbose("AFS token refused for %.100s",
-                                           s->authctxt->user);
-                               xfree(token);
-                       }
-                       break;
-#endif /* AFS */
-
                case SSH_CMSG_EXEC_SHELL:
                case SSH_CMSG_EXEC_CMD:
                        if (type == SSH_CMSG_EXEC_CMD) {
@@ -456,18 +399,13 @@ do_exec_no_pty(Session *s, const char *command)
        session_proctitle(s);
 
 #if defined(USE_PAM)
-       if (options.use_pam) {
-               do_pam_session(s->pw->pw_name, NULL);
+       if (options.use_pam && !use_privsep)
                do_pam_setcred(1);
-               if (is_pam_password_change_required())
-                       packet_disconnect("Password change required but no "
-                           "TTY available");
-       }
 #endif /* USE_PAM */
 
        /* Fork the child. */
        if ((pid = fork()) == 0) {
-               fatal_remove_all_cleanups();
+               is_child = 1;
 
                /* Child.  Reinitialize the log since the pid has changed. */
                log_init(__progname, options.log_level, options.log_facility, log_stderr);
@@ -554,6 +492,13 @@ do_exec_no_pty(Session *s, const char *command)
        close(inout[0]);
        close(err[0]);
 
+       /*
+        * Clear loginmsg, since it's the child's responsibility to display
+        * it to the user, otherwise multiple sessions may accumulate
+        * multiple copies of the login messages.
+        */
+       buffer_clear(&loginmsg);
+
        /*
         * Enter the interactive session.  Note: server_loop must be able to
         * handle the case that fdin and fdout are the same.
@@ -586,14 +531,15 @@ do_exec_pty(Session *s, const char *command)
 
 #if defined(USE_PAM)
        if (options.use_pam) {
-               do_pam_session(s->pw->pw_name, s->tty);
-               do_pam_setcred(1);
+               do_pam_set_tty(s->tty);
+               if (!use_privsep)
+                       do_pam_setcred(1);
        }
 #endif
 
        /* Fork the child. */
        if ((pid = fork()) == 0) {
-               fatal_remove_all_cleanups();
+               is_child = 1;
 
                /* Child.  Reinitialize the log because the pid has changed. */
                log_init(__progname, options.log_level, options.log_facility, log_stderr);
@@ -689,12 +635,12 @@ do_pre_login(Session *s)
                if (getpeername(packet_get_connection_in(),
                    (struct sockaddr *) & from, &fromlen) < 0) {
                        debug("getpeername: %.100s", strerror(errno));
-                       fatal_cleanup();
+                       cleanup_exit(255);
                }
        }
 
        record_utmp_only(pid, s->tty, s->pw->pw_name,
-           get_remote_name_or_ip(utmp_len, options.verify_reverse_mapping),
+           get_remote_name_or_ip(utmp_len, options.use_dns),
            (struct sockaddr *)&from, fromlen);
 }
 #endif
@@ -712,6 +658,14 @@ do_exec(Session *s, const char *command)
                debug("Forced command '%.900s'", command);
        }
 
+#ifdef GSSAPI
+       if (options.gss_authentication) {
+               temporarily_use_uid(s->pw);
+               ssh_gssapi_storecreds();
+               restore_uid();
+       }
+#endif
+
        if (s->ttyfd != -1)
                do_exec_pty(s, command);
        else
@@ -741,7 +695,7 @@ do_login(Session *s, const char *command)
                if (getpeername(packet_get_connection_in(),
                    (struct sockaddr *) & from, &fromlen) < 0) {
                        debug("getpeername: %.100s", strerror(errno));
-                       fatal_cleanup();
+                       cleanup_exit(255);
                }
        }
 
@@ -749,7 +703,7 @@ do_login(Session *s, const char *command)
        if (!use_privsep)
                record_login(pid, s->tty, pw->pw_name, pw->pw_uid,
                    get_remote_name_or_ip(utmp_len,
-                   options.verify_reverse_mapping),
+                   options.use_dns),
                    (struct sockaddr *)&from, fromlen);
 
 #ifdef USE_PAM
@@ -757,23 +711,18 @@ do_login(Session *s, const char *command)
         * If password change is needed, do it now.
         * This needs to occur before the ~/.hushlogin check.
         */
-       if (options.use_pam && is_pam_password_change_required()) {
-               print_pam_messages();
+       if (options.use_pam && !use_privsep && s->authctxt->force_pwchange) {
+               display_loginmsg();
                do_pam_chauthtok();
+               s->authctxt->force_pwchange = 0;
+               /* XXX - signal [net] parent to enable forwardings */
        }
 #endif
 
        if (check_quietlogin(s, command))
                return;
 
-#ifdef USE_PAM
-       if (options.use_pam && !is_pam_password_change_required())
-               print_pam_messages();
-#endif /* USE_PAM */
-#ifdef WITH_AIXAUTHENTICATE
-       if (aixloginmsg && *aixloginmsg)
-               printf("%s\n", aixloginmsg);
-#endif /* WITH_AIXAUTHENTICATE */
+       display_loginmsg();
 
 #ifndef NO_SSH_LASTLOG
        if (options.print_lastlog && s->last_login_time != 0) {
@@ -844,12 +793,23 @@ check_quietlogin(Session *s, const char *command)
  * Sets the value of the given variable in the environment.  If the variable
  * already exists, its value is overriden.
  */
-static void
+void
 child_set_env(char ***envp, u_int *envsizep, const char *name,
        const char *value)
 {
-       u_int i, namelen;
        char **env;
+       u_int envsize;
+       u_int i, namelen;
+
+       /*
+        * If we're passed an uninitialized list, allocate a single null
+        * entry before continuing.
+        */
+       if (*envp == NULL && *envsizep == 0) {
+               *envp = xmalloc(sizeof(char *));
+               *envp[0] = NULL;
+               *envsizep = 1;
+       }
 
        /*
         * Find the slot where the value should be stored.  If the variable
@@ -866,12 +826,13 @@ child_set_env(char ***envp, u_int *envsizep, const char *name,
                xfree(env[i]);
        } else {
                /* New variable.  Expand if necessary. */
-               if (i >= (*envsizep) - 1) {
-                       if (*envsizep >= 1000)
-                               fatal("child_set_env: too many env vars,"
-                                   " skipping: %.100s", name);
-                       (*envsizep) += 50;
-                       env = (*envp) = xrealloc(env, (*envsizep) * sizeof(char *));
+               envsize = *envsizep;
+               if (i >= envsize - 1) {
+                       if (envsize >= 1000)
+                               fatal("child_set_env: too many env vars");
+                       envsize += 50;
+                       env = (*envp) = xrealloc(env, envsize * sizeof(char *));
+                       *envsizep = envsize;
                }
                /* Need to set the NULL pointer at end of array beyond the new slot. */
                env[i + 1] = NULL;
@@ -927,6 +888,61 @@ read_environment_file(char ***env, u_int *envsize,
        fclose(f);
 }
 
+#ifdef HAVE_ETC_DEFAULT_LOGIN
+/*
+ * Return named variable from specified environment, or NULL if not present.
+ */
+static char *
+child_get_env(char **env, const char *name)
+{
+       int i;
+       size_t len;
+
+       len = strlen(name);
+       for (i=0; env[i] != NULL; i++)
+               if (strncmp(name, env[i], len) == 0 && env[i][len] == '=')
+                       return(env[i] + len + 1);
+       return NULL;
+}
+
+/*
+ * Read /etc/default/login.
+ * We pick up the PATH (or SUPATH for root) and UMASK.
+ */
+static void
+read_etc_default_login(char ***env, u_int *envsize, uid_t uid)
+{
+       char **tmpenv = NULL, *var;
+       u_int i, tmpenvsize = 0;
+       u_long mask;
+
+       /*
+        * We don't want to copy the whole file to the child's environment,
+        * so we use a temporary environment and copy the variables we're
+        * interested in.
+        */
+       read_environment_file(&tmpenv, &tmpenvsize, "/etc/default/login");
+
+       if (tmpenv == NULL)
+               return;
+
+       if (uid == 0)
+               var = child_get_env(tmpenv, "SUPATH");
+       else
+               var = child_get_env(tmpenv, "PATH");
+       if (var != NULL)
+               child_set_env(env, envsize, "PATH", var);
+
+       if ((var = child_get_env(tmpenv, "UMASK")) != NULL)
+               if (sscanf(var, "%5lo", &mask) == 1)
+                       umask((mode_t)mask);
+
+       for (i = 0; tmpenv[i] != NULL; i++)
+               xfree(tmpenv[i]);
+       xfree(tmpenv);
+}
+#endif /* HAVE_ETC_DEFAULT_LOGIN */
+
 void copy_environment(char **source, char ***env, u_int *envsize)
 {
        char *var_name, *var_val;
@@ -945,7 +961,7 @@ void copy_environment(char **source, char ***env, u_int *envsize)
 
                debug3("Copy environment: %s=%s", var_name, var_val);
                child_set_env(env, envsize, var_name, var_val);
-               
+
                xfree(var_name);
        }
 }
@@ -955,7 +971,7 @@ do_setup_env(Session *s, const char *shell)
 {
        char buf[256];
        u_int i, envsize;
-       char **env, *laddr;
+       char **env, *laddr, *path = NULL;
        struct passwd *pw = s->pw;
 
        /* Initialize the environment. */
@@ -971,8 +987,19 @@ do_setup_env(Session *s, const char *shell)
        copy_environment(environ, &env, &envsize);
 #endif
 
+#ifdef GSSAPI
+       /* Allow any GSSAPI methods that we've used to alter
+        * the childs environment as they see fit
+        */
+       ssh_gssapi_do_child(&env, &envsize);
+#endif
+
        if (!options.use_login) {
                /* Set basic environment. */
+               for (i = 0; i < s->num_env; i++)
+                       child_set_env(&env, &envsize, s->env[i].name, 
+                           s->env[i].val);
+
                child_set_env(&env, &envsize, "USER", pw->pw_name);
                child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
 #ifdef _AIX
@@ -992,12 +1019,15 @@ do_setup_env(Session *s, const char *shell)
                 * needed for loading shared libraries. So the path better
                 * remains intact here.
                 */
-#  ifdef SUPERUSER_PATH
-               child_set_env(&env, &envsize, "PATH", 
-                   s->pw->pw_uid == 0 ? SUPERUSER_PATH : _PATH_STDPATH);
-#  else 
-               child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
-#  endif /* SUPERUSER_PATH */
+#  ifdef HAVE_ETC_DEFAULT_LOGIN
+               read_etc_default_login(&env, &envsize, pw->pw_uid);
+               path = child_get_env(env, "PATH");
+#  endif /* HAVE_ETC_DEFAULT_LOGIN */
+               if (path == NULL || *path == '\0') {
+                       child_set_env(&env, &envsize, "PATH",
+                           s->pw->pw_uid == 0 ?
+                               SUPERUSER_PATH : _PATH_STDPATH);
+               }
 # endif /* HAVE_CYGWIN */
 #endif /* HAVE_LOGIN_CAP */
 
@@ -1066,15 +1096,10 @@ do_setup_env(Session *s, const char *shell)
                read_environment_file(&env, &envsize, "/etc/environment");
        }
 #endif
-#ifdef KRB4
-       if (s->authctxt->krb4_ticket_file)
-               child_set_env(&env, &envsize, "KRBTKFILE",
-                   s->authctxt->krb4_ticket_file);
-#endif
 #ifdef KRB5
-       if (s->authctxt->krb5_ticket_file)
+       if (s->authctxt->krb5_ccname)
                child_set_env(&env, &envsize, "KRB5CCNAME",
-                   s->authctxt->krb5_ticket_file);
+                   s->authctxt->krb5_ccname);
 #endif
 #ifdef USE_PAM
        /*
@@ -1082,8 +1107,13 @@ do_setup_env(Session *s, const char *shell)
         * been set by PAM.
         */
        if (options.use_pam) {
-               char **p = fetch_pam_environment();
+               char **p;
 
+               p = fetch_pam_child_environment();
+               copy_environment(p, &env, &envsize);
+               free_pam_environment(p);
+
+               p = fetch_pam_environment();
                copy_environment(p, &env, &envsize);
                free_pam_environment(p);
        }
@@ -1156,7 +1186,7 @@ do_rc_files(Session *s, const char *shell)
                if (debug_flag) {
                        fprintf(stderr,
                            "Running %.500s remove %.100s\n",
-                           options.xauth_location, s->auth_display);
+                           options.xauth_location, s->auth_display);
                        fprintf(stderr,
                            "%.500s add %.100s %.100s %.100s\n",
                            options.xauth_location, s->auth_display,
@@ -1215,12 +1245,19 @@ do_setusercontext(struct passwd *pw)
        {
 
 #ifdef HAVE_SETPCRED
-               setpcred(pw->pw_name);
+               if (setpcred(pw->pw_name, (char **)NULL) == -1)
+                       fatal("Failed to set process credentials");
 #endif /* HAVE_SETPCRED */
 #ifdef HAVE_LOGIN_CAP
 # ifdef __bsdi__
                setpgid(0, 0);
 # endif
+# ifdef USE_PAM
+               if (options.use_pam) {
+                       do_pam_session();
+                       do_pam_setcred(0);
+               }
+# endif /* USE_PAM */
                if (setusercontext(lc, pw, pw->pw_uid,
                    (LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) {
                        perror("unable to set user context");
@@ -1247,12 +1284,14 @@ do_setusercontext(struct passwd *pw)
                endgrent();
 # ifdef USE_PAM
                /*
-                * PAM credentials may take the form of supplementary groups. 
+                * PAM credentials may take the form of supplementary groups.
                 * These will have been wiped by the above initgroups() call.
                 * Reestablish them here.
                 */
-               if (options.use_pam)
+               if (options.use_pam) {
+                       do_pam_session();
                        do_pam_setcred(0);
+               }
 # endif /* USE_PAM */
 # if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY)
                irix_setusercontext(pw);
@@ -1272,6 +1311,22 @@ do_setusercontext(struct passwd *pw)
                fatal("Failed to set uids to %u.", (u_int) pw->pw_uid);
 }
 
+static void
+do_pwchange(Session *s)
+{
+       fprintf(stderr, "WARNING: Your password has expired.\n");
+       if (s->ttyfd != -1) {
+               fprintf(stderr,
+                   "You must change your password now and login again!\n");
+               execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL);
+               perror("passwd");
+       } else {
+               fprintf(stderr,
+                   "Password change required but no TTY available.\n");
+       }
+       exit(1);
+}
+
 static void
 launch_login(struct passwd *pw, const char *hostname)
 {
@@ -1293,6 +1348,40 @@ launch_login(struct passwd *pw, const char *hostname)
        exit(1);
 }
 
+static void
+child_close_fds(void)
+{
+       int i;
+
+       if (packet_get_connection_in() == packet_get_connection_out())
+               close(packet_get_connection_in());
+       else {
+               close(packet_get_connection_in());
+               close(packet_get_connection_out());
+       }
+       /*
+        * Close all descriptors related to channels.  They will still remain
+        * open in the parent.
+        */
+       /* XXX better use close-on-exec? -markus */
+       channel_close_all();
+
+       /*
+        * Close any extra file descriptors.  Note that there may still be
+        * descriptors left by system functions.  They will be closed later.
+        */
+       endpwent();
+
+       /*
+        * 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.
+        */
+       for (i = 3; i < 64; i++)
+               close(i);
+}
+
 /*
  * Performs common processing for the child, such as setting up the
  * environment, closing extra file descriptors, setting the user and group
@@ -1306,11 +1395,18 @@ do_child(Session *s, const char *command)
        char *argv[10];
        const char *shell, *shell0, *hostname = NULL;
        struct passwd *pw = s->pw;
-       u_int i;
 
        /* remove hostkey from the child's memory */
        destroy_sensitive_data();
 
+       /* Force a password change */
+       if (s->authctxt->force_pwchange) {
+               do_setusercontext(pw);
+               child_close_fds();
+               do_pwchange(s);
+               exit(1);
+       }
+
        /* login(1) is only called if we execute the login shell */
        if (options.use_login && command != NULL)
                options.use_login = 0;
@@ -1353,7 +1449,7 @@ do_child(Session *s, const char *command)
        /* we have to stash the hostname before we close our socket. */
        if (options.use_login)
                hostname = get_remote_name_or_ip(utmp_len,
-                   options.verify_reverse_mapping);
+                   options.use_dns);
        /*
         * Close the connection descriptors; note that this is the child, and
         * the server will still have the socket open, and it is important
@@ -1361,33 +1457,7 @@ do_child(Session *s, const char *command)
         * closed before building the environment, as we call
         * get_remote_ipaddr there.
         */
-       if (packet_get_connection_in() == packet_get_connection_out())
-               close(packet_get_connection_in());
-       else {
-               close(packet_get_connection_in());
-               close(packet_get_connection_out());
-       }
-       /*
-        * Close all descriptors related to channels.  They will still remain
-        * open in the parent.
-        */
-       /* XXX better use close-on-exec? -markus */
-       channel_close_all();
-
-       /*
-        * Close any extra file descriptors.  Note that there may still be
-        * descriptors left by system functions.  They will be closed later.
-        */
-       endpwent();
-
-       /*
-        * 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.
-        */
-       for (i = 3; i < 64; i++)
-               close(i);
+       child_close_fds();
 
        /*
         * Must take new environment into use so that .ssh/rc,
@@ -1395,17 +1465,31 @@ do_child(Session *s, const char *command)
         */
        environ = env;
 
-#ifdef AFS
-       /* Try to get AFS tokens for the local cell. */
-       if (k_hasafs()) {
+#if defined(KRB5) && defined(USE_AFS)
+       /*
+        * At this point, we check to see if AFS is active and if we have
+        * a valid Kerberos 5 TGT. If so, it seems like a good idea to see
+        * if we can (and need to) extend the ticket into an AFS token. If
+        * we don't do this, we run into potential problems if the user's
+        * home directory is in AFS and it's not world-readable.
+        */
+
+       if (options.kerberos_get_afs_token && k_hasafs() &&
+            (s->authctxt->krb5_ctx != NULL)) {
                char cell[64];
 
+               debug("Getting AFS token");
+
+               k_setpag();
+
                if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
-                       krb_afslog(cell, 0);
+                       krb5_afslog(s->authctxt->krb5_ctx,
+                           s->authctxt->krb5_fwd_ccache, cell, NULL);
 
-               krb_afslog(0, 0);
+               krb5_afslog_home(s->authctxt->krb5_ctx,
+                   s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir);
        }
-#endif /* AFS */
+#endif
 
        /* Change current directory to the user\'s home directory. */
        if (chdir(pw->pw_dir) < 0) {
@@ -1528,7 +1612,7 @@ session_open(Authctxt *authctxt, int chanid)
        }
        s->authctxt = authctxt;
        s->pw = authctxt->pw;
-       if (s->pw == NULL)
+       if (s->pw == NULL || !authctxt->valid)
                fatal("no user for session %d", s->self);
        debug("session_open: session %d: link with channel %d", s->self, chanid);
        s->chanid = chanid;
@@ -1650,11 +1734,6 @@ session_pty_req(Session *s)
                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(session_pty_cleanup, (void *)s);
        if (!use_privsep)
                pty_setowner(s->pw, s->tty);
 
@@ -1742,6 +1821,55 @@ session_exec_req(Session *s)
        return 1;
 }
 
+static int
+session_break_req(Session *s)
+{
+       u_int break_length;
+
+       break_length = packet_get_int();        /* ignored */
+       packet_check_eom();
+
+       if (s->ttyfd == -1 ||
+           tcsendbreak(s->ttyfd, 0) < 0)
+               return 0;
+       return 1;
+}
+
+static int
+session_env_req(Session *s)
+{
+       char *name, *val;
+       u_int name_len, val_len, i;
+
+       name = packet_get_string(&name_len);
+       val = packet_get_string(&val_len);
+       packet_check_eom();
+
+       /* Don't set too many environment variables */
+       if (s->num_env > 128) {
+               debug2("Ignoring env request %s: too many env vars", name);
+               goto fail;
+       }
+
+       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[s->num_env].name = name;
+                       s->env[s->num_env].val = val;
+                       s->num_env++;
+                       return (1);
+               }
+       }
+       debug2("Ignoring env request %s: disallowed name", name);
+
+ fail:
+       xfree(name);
+       xfree(val);
+       return (0);
+}
+
 static int
 session_auth_agent_req(Session *s)
 {
@@ -1789,6 +1917,10 @@ session_input_channel_req(Channel *c, const char *rtype)
                        success = session_auth_agent_req(s);
                } else if (strcmp(rtype, "subsystem") == 0) {
                        success = session_subsystem_req(s);
+               } else if (strcmp(rtype, "break") == 0) {
+                       success = session_break_req(s);
+               } else if (strcmp(rtype, "env") == 0) {
+                       success = session_env_req(s);
                }
        }
        if (strcmp(rtype, "window-change") == 0) {
@@ -1820,10 +1952,8 @@ session_set_fds(Session *s, int fdin, int fdout, int fderr)
  * (e.g., due to a dropped connection).
  */
 void
-session_pty_cleanup2(void *session)
+session_pty_cleanup2(Session *s)
 {
-       Session *s = session;
-
        if (s == NULL) {
                error("session_pty_cleanup: no session");
                return;
@@ -1854,9 +1984,9 @@ session_pty_cleanup2(void *session)
 }
 
 void
-session_pty_cleanup(void *session)
+session_pty_cleanup(Session *s)
 {
-       PRIVSEP(session_pty_cleanup2(session));
+       PRIVSEP(session_pty_cleanup2(s));
 }
 
 static char *
@@ -1928,11 +2058,11 @@ session_exit_message(Session *s, int status)
 void
 session_close(Session *s)
 {
+       int i;
+
        debug("session_close: session %d pid %ld", s->self, (long)s->pid);
-       if (s->ttyfd != -1) {
-               fatal_remove_cleanup(session_pty_cleanup, (void *)s);
+       if (s->ttyfd != -1)
                session_pty_cleanup(s);
-       }
        if (s->term)
                xfree(s->term);
        if (s->display)
@@ -1944,6 +2074,12 @@ 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)
+               xfree(s->env);
        session_proctitle(s);
 }
 
@@ -1981,10 +2117,8 @@ session_close_by_channel(int id, void *arg)
                 * delay detach of session, but release pty, since
                 * the fd's to the child are already closed
                 */
-               if (s->ttyfd != -1) {
-                       fatal_remove_cleanup(session_pty_cleanup, (void *)s);
+               if (s->ttyfd != -1)
                        session_pty_cleanup(s);
-               }
                return;
        }
        /* detach by removing callback */
@@ -2019,13 +2153,13 @@ session_tty_list(void)
        for (i = 0; i < MAX_SESSIONS; i++) {
                Session *s = &sessions[i];
                if (s->used && s->ttyfd != -1) {
-                       
+
                        if (strncmp(s->tty, "/dev/", 5) != 0) {
                                cp = strrchr(s->tty, '/');
                                cp = (cp == NULL) ? s->tty : cp + 1;
                        } else
                                cp = s->tty + 5;
-                       
+
                        if (buf[0] != '\0')
                                strlcat(buf, ",", sizeof buf);
                        strlcat(buf, cp, sizeof buf);
@@ -2126,3 +2260,50 @@ do_authenticated2(Authctxt *authctxt)
 {
        server_loop2(authctxt);
 }
+
+void
+do_cleanup(Authctxt *authctxt)
+{
+       static int called = 0;
+
+       debug("do_cleanup");
+
+       /* no cleanup if we're in the child for login shell */
+       if (is_child)
+               return;
+
+       /* avoid double cleanup */
+       if (called)
+               return;
+       called = 1;
+
+       if (authctxt == NULL)
+               return;
+#ifdef KRB5
+       if (options.kerberos_ticket_cleanup &&
+           authctxt->krb5_ctx)
+               krb5_cleanup_proc(authctxt);
+#endif
+
+#ifdef GSSAPI
+       if (compat20 && options.gss_cleanup_creds)
+               ssh_gssapi_cleanup_creds();
+#endif
+
+#ifdef USE_PAM
+       if (options.use_pam) {
+               sshpam_cleanup();
+               sshpam_thread_cleanup();
+       }
+#endif
+
+       /* remove agent socket */
+       auth_sock_cleanup_proc(authctxt->pw);
+
+       /*
+        * Cleanup ptys/utmp only if privsep is disabled,
+        * or if running in monitor.
+        */
+       if (!use_privsep || mm_is_monitor())
+               session_destroy_all(session_pty_cleanup2);
+}
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