- (bal) OpenBSD CVS Sync

   - markus@cvs.openbsd.org 2002/02/15 23:11:26
     [session.c]
     split do_child(), ok mouring@

Compiles under Redhat 7.2.. I cannot give any promises.. but I spent a
good hour and half ensure all the right bits are in the right spots.. and
it does seem to help out quite a bit for readiblity.

2 files changed, 253 insertions, 217 deletions

diff --git a/ChangeLog b/ChangeLog
index a7ef8510f..03dd380b5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -48,6 +48,11 @@
  - (bal) Migrated AIX getuserattr and usrinfo code to 
    openbsd-compat/port-aix.[c] to improve readilbity of do_child() and
    simplify our diffs against upstream source.
+ - (bal) OpenBSD CVS Sync
+   - markus@cvs.openbsd.org 2002/02/15 23:11:26
+     [session.c]
+     split do_child(), ok mouring@
+
 
 20020218
  - (tim) newer config.guess from ftp://ftp.gnu.org/gnu/config/config.guess
@@ -7645,4 +7650,4 @@
  - Wrote replacements for strlcpy and mkdtemp
  - Released 1.0pre1
 
-$Id: ChangeLog,v 1.1867 2002/02/19 20:27:55 mouring Exp $
+$Id: ChangeLog,v 1.1868 2002/02/19 21:50:43 mouring Exp $
diff --git a/session.c b/session.c
index 2134d917a..e4934a415 100644
--- a/session.c
+++ b/session.c
@@ -33,7 +33,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: session.c,v 1.126 2002/02/14 23:28:00 markus Exp $");
+RCSID("$OpenBSD: session.c,v 1.127 2002/02/15 23:11:26 markus Exp $");
 
 #include "ssh.h"
 #include "ssh1.h"
@@ -657,6 +657,7 @@ do_exec(Session *s, const char *command)
         original_command = NULL;
 }
 
+
 /* administrative, login(1)-like work */
 void
 do_login(Session *s, const char *command)
@@ -677,7 +678,7 @@ do_login(Session *s, const char *command)
         if (packet_connection_is_on_socket()) {
                 fromlen = sizeof(from);
                 if (getpeername(packet_get_connection_in(),
-                     (struct sockaddr *) & from, &fromlen) < 0) {
+                    (struct sockaddr *) & from, &fromlen) < 0) {
                         debug("getpeername: %.100s", strerror(errno));
                         fatal_cleanup();
                 }
@@ -883,134 +884,13 @@ void copy_environment(char **source, char ***env, u_int *envsize)
         }
 }
 
-/*
- * Performs common processing for the child, such as setting up the
- * environment, closing extra file descriptors, setting the user and group
- * ids, and executing the command or shell.
- */
-void
-do_child(Session *s, const char *command)
+static char **
+do_setup_env(Session *s, const char *shell)
 {
-        const char *shell, *hostname = NULL, *cp = NULL;
-        struct passwd *pw = s->pw;
         char buf[256];
-        char cmd[1024];
-        FILE *f = NULL;
-        u_int envsize, i;
+        u_int i, envsize;
         char **env;
-        extern char **environ;
-        struct stat st;
-        char *argv[10];
-        int do_xauth;
-
-        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;
-
-#if !defined(HAVE_OSF_SIA)
-        if (!options.use_login) {
-# ifdef HAVE_LOGIN_CAP
-                if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid)
-                        f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN,
-                            _PATH_NOLOGIN), "r");
-# else /* HAVE_LOGIN_CAP */
-                if (pw->pw_uid)
-                        f = fopen(_PATH_NOLOGIN, "r");
-# endif /* HAVE_LOGIN_CAP */
-                if (f) {
-                        /* /etc/nologin exists.  Print its contents and exit. */
-                        while (fgets(buf, sizeof(buf), f))
-                                fputs(buf, stderr);
-                        fclose(f);
-                        exit(254);
-                }
-        }
-#endif /* 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
-                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 */
-# ifdef HAVE_LOGIN_CAP
-                        if (setusercontext(lc, pw, pw->pw_uid,
-                            (LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) {
-                                perror("unable to set user context");
-                                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) {
-                                perror("setgid");
-                                exit(1);
-                        }
-                        /* Initialize the group list. */
-                        if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
-                                perror("initgroups");
-                                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 */
-#  if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY)
-                        irix_setusercontext(pw);
-#  endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */
-#ifdef _AIX
-                        aix_usrinfo(s)
-#endif
-
-                        /* Permanently switch to the desired 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 %u.", (u_int) pw->pw_uid);
-        }
-        /*
-         * Get the shell from the password data.  An empty shell field is
-         * legal, and means /bin/sh.
-         */
-        shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
-#ifdef HAVE_LOGIN_CAP
-        shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell);
-#endif
+        struct passwd *pw = s->pw;
 
         /* Initialize the environment. */
         envsize = 100;
@@ -1060,7 +940,7 @@ do_child(Session *s, const char *command)
                 while (custom_environment) {
                         struct envstring *ce = custom_environment;
                         char *s = ce->s;
-                        int i;
+
                         for (i = 0; s[i] != '=' && s[i]; i++)
                                 ;
                         if (s[i] == '=') {
@@ -1074,7 +954,7 @@ do_child(Session *s, const char *command)
         }
 
         snprintf(buf, sizeof buf, "%.50s %d %d",
-                 get_remote_ipaddr(), get_remote_port(), get_local_port());
+            get_remote_ipaddr(), get_remote_port(), get_local_port());
         child_set_env(&env, &envsize, "SSH_CLIENT", buf);
 
         if (s->ttyfd != -1)
@@ -1125,6 +1005,206 @@ do_child(Session *s, const char *command)
                 for (i = 0; env[i]; i++)
                         fprintf(stderr, "  %.200s\n", env[i]);
         }
+        return env;
+}
+
+/*
+ * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found
+ * first in this order).
+ */
+static void
+do_rc_files(Session *s, const char *shell)
+{
+        FILE *f = NULL;
+        char cmd[1024];
+        int do_xauth;
+        struct stat st;
+
+        do_xauth =
+            s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL;
+
+        /* 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 %s\n", cmd);
+                f = popen(cmd, "w");
+                if (f) {
+                        if (do_xauth)
+                                fprintf(f, "%s %s\n", s->auth_proto,
+                                    s->auth_data);
+                        pclose(f);
+                } else
+                        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 %s %s\n", _PATH_BSHELL,
+                            _PATH_SSH_SYSTEM_RC);
+                f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w");
+                if (f) {
+                        if (do_xauth)
+                                fprintf(f, "%s %s\n", s->auth_proto,
+                                    s->auth_data);
+                        pclose(f);
+                } else
+                        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 (debug_flag) {
+                        fprintf(stderr,
+                            "Running %.100s add "
+                            "%.100s %.100s %.100s\n",
+                            options.xauth_location, s->auth_display,
+                            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->auth_display, s->auth_proto,
+                            s->auth_data);
+                        pclose(f);
+                } else {
+                        fprintf(stderr, "Could not run %s\n",
+                            cmd);
+                }
+        }
+}
+
+static void
+do_nologin(struct passwd *pw)
+{
+        FILE *f = NULL;
+        char buf[1024];
+
+#ifdef HAVE_LOGIN_CAP
+        if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid)
+                f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN,
+                    _PATH_NOLOGIN), "r");
+#else
+        if (pw->pw_uid)
+                f = fopen(_PATH_NOLOGIN, "r");
+#endif
+        if (f) {
+                /* /etc/nologin exists.  Print its contents and exit. */
+                while (fgets(buf, sizeof(buf), f))
+                        fputs(buf, stderr);
+                fclose(f);
+                exit(254);
+        }
+}
+
+/* Set login name, uid, gid, and groups. */
+static void
+do_setusercontext(struct passwd *pw)
+{
+#ifdef HAVE_CYGWIN
+        if (iswinnt) {
+#else /* HAVE_CYGWIN */
+        if (getuid() == 0 || geteuid() == 0) {
+#endif /* HAVE_CYGWIN */
+#ifdef HAVE_GETUSERATTR
+                set_limits_from_userattr(pw->pw_name);
+#endif /* HAVE_GETUSERATTR */
+#ifdef HAVE_LOGIN_CAP
+                if (setusercontext(lc, pw, pw->pw_uid,
+                    (LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) {
+                        perror("unable to set user context");
+                        exit(1);
+                }
+#else
+# 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) {
+                        perror("setgid");
+                        exit(1);
+                }
+                /* Initialize the group list. */
+                if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
+                        perror("initgroups");
+                        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 */
+# if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY)
+                irix_setusercontext(pw);
+#  endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */
+#ifdef _AIX
+                aix_usrinfo(s)
+#endif
+                /* Permanently switch to the desired uid. */
+                permanently_set_uid(pw);
+#endif
+        }
+        if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
+                fatal("Failed to set uids to %u.", (u_int) pw->pw_uid);
+}
+
+/*
+ * Performs common processing for the child, such as setting up the
+ * environment, closing extra file descriptors, setting the user and group
+ * ids, and executing the command or shell.
+ */
+void
+do_child(Session *s, const char *command)
+{
+        extern char **environ;
+        char **env;
+        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();
+
+        /* login(1) is only called if we execute the login shell */
+        if (options.use_login && command != NULL)
+                options.use_login = 0;
+
+        /*
+         * 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
+                session_setup_sia(pw->pw_name, s->ttyfd == -1 ? NULL : s->tty);
+                if (!check_quietlogin(s, command))
+                        do_motd();
+#else /* HAVE_OSF_SIA */
+                do_nologin(pw);
+                do_setusercontext(pw);
+#endif /* HAVE_OSF_SIA */
+        }
+
+        /*
+         * Get the shell from the password data.  An empty shell field is
+         * legal, and means /bin/sh.
+         */
+        shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
+#ifdef HAVE_LOGIN_CAP
+        shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell);
+#endif
+
+        env = do_setup_env(s, shell);
+
         /* we have to stash the hostname before we close our socket. */
         if (options.use_login)
                 hostname = get_remote_name_or_ip(utmp_len,
@@ -1192,114 +1272,65 @@ do_child(Session *s, const char *command)
 #endif
         }
 
-        /*
-         * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found
-         * first in this order).
-         */
-        if (!options.use_login) {
-                /* 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 %s\n", cmd);
-                        f = popen(cmd, "w");
-                        if (f) {
-                                if (do_xauth)
-                                        fprintf(f, "%s %s\n", s->auth_proto,
-                                            s->auth_data);
-                                pclose(f);
-                        } else
-                                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 %s %s\n", _PATH_BSHELL,
-                                    _PATH_SSH_SYSTEM_RC);
-                        f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w");
-                        if (f) {
-                                if (do_xauth)
-                                        fprintf(f, "%s %s\n", s->auth_proto,
-                                            s->auth_data);
-                                pclose(f);
-                        } else
-                                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 (debug_flag) {
-                                fprintf(stderr,
-                                    "Running %.100s add "
-                                    "%.100s %.100s %.100s\n",
-                                    options.xauth_location, s->auth_display,
-                                    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->auth_display, 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. */
-                cp = strrchr(shell, '/');
-                if (cp)
-                        cp++;
-                else
-                        cp = shell;
-        }
+        if (!options.use_login)
+                do_rc_files(s, shell);
 
         /* restore SIGPIPE for child */
         signal(SIGPIPE,  SIG_DFL);
 
+        if (options.use_login) {
+                /* Launch login(1). */
+
+                execl(LOGIN_PROGRAM, "login", "-h", hostname,
+#ifdef LOGIN_NEEDS_TERM
+                    (s->term ? s->term : "unknown"),
+#endif /* LOGIN_NEEDS_TERM */
+                    "-p", "-f", "--", pw->pw_name, (char *)NULL);
+
+                /* Login couldn't be executed, die. */
+
+                perror("login");
+                exit(1);
+        }
+
+        /* Get the last component of the shell name. */
+        if ((shell0 = strrchr(shell, '/')) != NULL)
+                shell0++;
+        else
+                shell0 = shell;
+
         /*
          * 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
          * this is a login shell.
          */
         if (!command) {
-                if (!options.use_login) {
-                        char buf[256];
+                char argv0[256];
 
-                        /* Start the shell.  Set initial character to '-'. */
-                        buf[0] = '-';
-                        strlcpy(buf + 1, cp, sizeof(buf) - 1);
+                /* Start the shell.  Set initial character to '-'. */
+                argv0[0] = '-';
 
-                        /* Execute the shell. */
-                        argv[0] = buf;
-                        argv[1] = NULL;
-                        execve(shell, argv, env);
-
-                        /* Executing the shell failed. */
+                if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1)
+                    >= sizeof(argv0) - 1) {
+                        errno = EINVAL;
                         perror(shell);
                         exit(1);
+                }
 
-                } else {
-                        /* Launch login(1). */
-
-                        execl(LOGIN_PROGRAM, "login", "-h", hostname,
-#ifdef LOGIN_NEEDS_TERM
-                            s->term? s->term : "unknown",
-#endif
-                            "-p", "-f", "--", pw->pw_name, (char *)NULL);
-
-                        /* Login couldn't be executed, die. */
+                /* Execute the shell. */
+                argv[0] = argv0;
+                argv[1] = NULL;
+                execve(shell, argv, env);
 
-                        perror("login");
-                        exit(1);
-                }
+                /* Executing the shell failed. */
+                perror(shell);
+                exit(1);
         }
         /*
          * Execute the command using the user's shell.  This uses the -c
          * option to execute the command.
          */
-        argv[0] = (char *) cp;
+        argv[0] = (char *) shell0;
         argv[1] = "-c";
         argv[2] = (char *) command;
         argv[3] = NULL;