1 files changed, 157 insertions, 126 deletions

diff --git a/session.c b/session.c
index ec4a23ac5..4497f5c0b 100644
--- a/session.c
+++ b/session.c
@@ -33,7 +33,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: session.c,v 1.154 2003/03/05 22:33:43 markus Exp $");
+RCSID("$OpenBSD: session.c,v 1.163 2003/08/31 13:29:05 markus Exp $");
 
 #include "ssh.h"
 #include "ssh1.h"
@@ -58,10 +58,8 @@ RCSID("$OpenBSD: session.c,v 1.154 2003/03/05 22:33:43 markus Exp $");
 #include "session.h"
 #include "monitor_wrap.h"
 
-#ifdef HAVE_CYGWIN
-#include <windows.h>
-#include <sys/cygwin.h>
-#define is_winnt       (GetVersion() < 0x80000000)
+#ifdef GSSAPI
+#include "ssh-gss.h"
 #endif
 
 /* func */
@@ -95,6 +93,7 @@ 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;
@@ -103,10 +102,6 @@ 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
@@ -192,7 +187,7 @@ auth_input_request_forwarding(struct passwd * pw)
         nc = channel_new("auth socket",
             SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
             CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
-            0, xstrdup("auth socket"), 1);
+            0, "auth socket", 1);
         strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
         return 1;
 }
@@ -225,10 +220,6 @@ do_authenticated(Authctxt *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);
@@ -341,58 +332,6 @@ 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) {
@@ -412,7 +351,7 @@ do_authenticated1(Authctxt *authctxt)
                          * Any unknown messages in this phase are ignored,
                          * and a failure message is returned.
                          */
-                        log("Unknown packet type received after authentication: %d", type);
+                        logit("Unknown packet type received after authentication: %d", type);
                 }
                 packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE);
                 packet_send();
@@ -456,11 +395,12 @@ do_exec_no_pty(Session *s, const char *command)
         session_proctitle(s);
 
 #if defined(USE_PAM)
-        do_pam_session(s->pw->pw_name, NULL);
-        do_pam_setcred(1);
-        if (is_pam_password_change_required())
-                packet_disconnect("Password change required but no "
-                    "TTY available");
+        if (options.use_pam) {
+                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. */
@@ -583,8 +523,10 @@ do_exec_pty(Session *s, const char *command)
         ttyfd = s->ttyfd;
 
 #if defined(USE_PAM)
-        do_pam_session(s->pw->pw_name, s->tty);
-        do_pam_setcred(1);
+        if (options.use_pam) {
+                do_pam_set_tty(s->tty);
+                do_pam_setcred(1);
+        }
 #endif
 
         /* Fork the child. */
@@ -690,7 +632,7 @@ do_pre_login(Session *s)
         }
 
         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
@@ -708,6 +650,14 @@ 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
@@ -745,7 +695,7 @@ 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
@@ -753,9 +703,10 @@ do_login(Session *s, const char *command)
          * If password change is needed, do it now.
          * This needs to occur before the ~/.hushlogin check.
          */
-        if (is_pam_password_change_required()) {
+        if (options.use_pam && is_pam_password_change_required()) {
                 print_pam_messages();
                 do_pam_chauthtok();
+                /* XXX - signal [net] parent to enable forwardings */
         }
 #endif
 
@@ -763,13 +714,16 @@ do_login(Session *s, const char *command)
                 return;
 
 #ifdef USE_PAM
-        if (!is_pam_password_change_required())
+        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 post-login message */
+        if (buffer_len(&loginmsg) > 0) {
+                buffer_append(&loginmsg, "\0", 1);
+                printf("%s\n", (char *)buffer_ptr(&loginmsg));
+        }
+        buffer_free(&loginmsg);
 
 #ifndef NO_SSH_LASTLOG
         if (options.print_lastlog && s->last_login_time != 0) {
@@ -840,13 +794,22 @@ 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)
 {
-        char **env;
-        u_int envsize;
         u_int i, namelen;
+        char **env;
+
+        /*
+         * 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
@@ -863,13 +826,12 @@ child_set_env(char ***envp, u_int *envsizep, const char *name,
                 xfree(env[i]);
         } else {
                 /* New variable.  Expand if necessary. */
-                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;
+                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 *));
                 }
                 /* Need to set the NULL pointer at end of array beyond the new slot. */
                 env[i + 1] = NULL;
@@ -925,6 +887,59 @@ 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;
+        size_t tmpenvsize = 0;
+        mode_t 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 (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(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;
@@ -953,7 +968,7 @@ 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. */
@@ -969,6 +984,13 @@ 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. */
                 child_set_env(&env, &envsize, "USER", pw->pw_name);
@@ -990,12 +1012,15 @@ 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 */
 
@@ -1064,11 +1089,6 @@ 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)
                 child_set_env(&env, &envsize, "KRB5CCNAME",
@@ -1079,10 +1099,9 @@ do_setup_env(Session *s, const char *shell)
          * Pull in any environment variables that may have
          * been set by PAM.
          */
-        {
-                char **p;
+        if (options.use_pam) {
+                char **p = fetch_pam_environment();
 
-                p = fetch_pam_environment();
                 copy_environment(p, &env, &envsize);
                 free_pam_environment(p);
         }
@@ -1194,7 +1213,7 @@ do_nologin(struct passwd *pw)
 #endif
         if (f) {
                 /* /etc/nologin exists.  Print its contents and exit. */
-                log("User %.100s not allowed because %s exists",
+                logit("User %.100s not allowed because %s exists",
                     pw->pw_name, _PATH_NOLOGIN);
                 while (fgets(buf, sizeof(buf), f))
                         fputs(buf, stderr);
@@ -1214,7 +1233,8 @@ 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__
@@ -1250,7 +1270,10 @@ do_setusercontext(struct passwd *pw)
                  * These will have been wiped by the above initgroups() call.
                  * Reestablish them here.
                  */
-                do_pam_setcred(0);
+                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);
@@ -1351,7 +1374,7 @@ 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
@@ -1393,18 +1416,6 @@ do_child(Session *s, const char *command)
          */
         environ = env;
 
-#ifdef AFS
-        /* Try to get AFS tokens for the local cell. */
-        if (k_hasafs()) {
-                char cell[64];
-
-                if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
-                        krb_afslog(cell, 0);
-
-                krb_afslog(0, 0);
-        }
-#endif /* AFS */
-
         /* 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",
@@ -1674,7 +1685,7 @@ session_subsystem_req(Session *s)
         int i;
 
         packet_check_eom();
-        log("subsystem request for %.100s", subsys);
+        logit("subsystem request for %.100s", subsys);
 
         for (i = 0; i < options.num_subsystems; i++) {
                 if (strcmp(subsys, options.subsystem_name[i]) == 0) {
@@ -1693,7 +1704,7 @@ session_subsystem_req(Session *s)
         }
 
         if (!success)
-                log("subsystem request for %.100s failed, subsystem not found",
+                logit("subsystem request for %.100s failed, subsystem not found",
                     subsys);
 
         xfree(subsys);
@@ -1741,6 +1752,20 @@ session_exec_req(Session *s)
 }
 
 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_auth_agent_req(Session *s)
 {
         static int called = 0;
@@ -1764,7 +1789,7 @@ session_input_channel_req(Channel *c, const char *rtype)
         Session *s;
 
         if ((s = session_by_channel(c->self)) == NULL) {
-                log("session_input_channel_req: no session %d req %.100s",
+                logit("session_input_channel_req: no session %d req %.100s",
                     c->self, rtype);
                 return 0;
         }
@@ -1787,6 +1812,8 @@ 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);
                 }
         }
         if (strcmp(rtype, "window-change") == 0) {
@@ -2123,4 +2150,8 @@ static void
 do_authenticated2(Authctxt *authctxt)
 {
         server_loop2(authctxt);
+#if defined(GSSAPI)
+        if (options.gss_cleanup_creds)
+                ssh_gssapi_cleanup_creds(NULL);
+#endif
 }