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-rw-r--r--usr.bin/login/login.c594
1 files changed, 594 insertions, 0 deletions
diff --git a/usr.bin/login/login.c b/usr.bin/login/login.c
new file mode 100644
index 0000000..ef75733
--- /dev/null
+++ b/usr.bin/login/login.c
@@ -0,0 +1,594 @@
+/*-
+ * Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994
+ * The Regents of the University of California. 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.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
+ */
+
+#ifndef lint
+static char copyright[] =
+"@(#) Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994\n\
+ The Regents of the University of California. All rights reserved.\n";
+#endif /* not lint */
+
+#ifndef lint
+static char sccsid[] = "@(#)login.c 8.4 (Berkeley) 4/2/94";
+#endif /* not lint */
+
+/*
+ * login [ name ]
+ * login -h hostname (for telnetd, etc.)
+ * login -f name (for pre-authenticated login: datakit, xterm, etc.)
+ */
+
+#include <sys/param.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <sys/file.h>
+
+#include <err.h>
+#include <errno.h>
+#include <grp.h>
+#include <pwd.h>
+#include <setjmp.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <syslog.h>
+#include <ttyent.h>
+#include <tzfile.h>
+#include <unistd.h>
+#include <utmp.h>
+
+#include "pathnames.h"
+
+void badlogin __P((char *));
+void checknologin __P((void));
+void dolastlog __P((int));
+void getloginname __P((void));
+void motd __P((void));
+int rootterm __P((char *));
+void sigint __P((int));
+void sleepexit __P((int));
+char *stypeof __P((char *));
+void timedout __P((int));
+#ifdef KERBEROS
+int klogin __P((struct passwd *, char *, char *, char *));
+#endif
+
+extern void login __P((struct utmp *));
+
+#define TTYGRPNAME "tty" /* name of group to own ttys */
+
+/*
+ * This bounds the time given to login. Not a define so it can
+ * be patched on machines where it's too small.
+ */
+u_int timeout = 300;
+
+#ifdef KERBEROS
+int notickets = 1;
+char *instance;
+char *krbtkfile_env;
+int authok;
+#endif
+
+struct passwd *pwd;
+int failures;
+char term[64], *envinit[1], *hostname, *username, *tty;
+
+int
+main(argc, argv)
+ int argc;
+ char *argv[];
+{
+ extern char **environ;
+ struct group *gr;
+ struct stat st;
+ struct timeval tp;
+ struct utmp utmp;
+ int ask, ch, cnt, fflag, hflag, pflag, quietlog, rootlogin, rval;
+ uid_t uid;
+ char *domain, *p, *salt, *ttyn;
+ char tbuf[MAXPATHLEN + 2], tname[sizeof(_PATH_TTY) + 10];
+ char localhost[MAXHOSTNAMELEN];
+
+ (void)signal(SIGALRM, timedout);
+ (void)alarm(timeout);
+ (void)signal(SIGQUIT, SIG_IGN);
+ (void)signal(SIGINT, SIG_IGN);
+ (void)setpriority(PRIO_PROCESS, 0, 0);
+
+ openlog("login", LOG_ODELAY, LOG_AUTH);
+
+ /*
+ * -p is used by getty to tell login not to destroy the environment
+ * -f is used to skip a second login authentication
+ * -h is used by other servers to pass the name of the remote
+ * host to login so that it may be placed in utmp and wtmp
+ */
+ domain = NULL;
+ if (gethostname(localhost, sizeof(localhost)) < 0)
+ syslog(LOG_ERR, "couldn't get local hostname: %m");
+ else
+ domain = strchr(localhost, '.');
+
+ fflag = hflag = pflag = 0;
+ uid = getuid();
+ while ((ch = getopt(argc, argv, "fh:p")) != EOF)
+ switch (ch) {
+ case 'f':
+ fflag = 1;
+ break;
+ case 'h':
+ if (uid)
+ errx(1, "-h option: %s", strerror(EPERM));
+ hflag = 1;
+ if (domain && (p = strchr(optarg, '.')) &&
+ strcasecmp(p, domain) == 0)
+ *p = 0;
+ hostname = optarg;
+ break;
+ case 'p':
+ pflag = 1;
+ break;
+ case '?':
+ default:
+ if (!uid)
+ syslog(LOG_ERR, "invalid flag %c", ch);
+ (void)fprintf(stderr,
+ "usage: login [-fp] [-h hostname] [username]\n");
+ exit(1);
+ }
+ argc -= optind;
+ argv += optind;
+
+ if (*argv) {
+ username = *argv;
+ ask = 0;
+ } else
+ ask = 1;
+
+ for (cnt = getdtablesize(); cnt > 2; cnt--)
+ (void)close(cnt);
+
+ ttyn = ttyname(STDIN_FILENO);
+ if (ttyn == NULL || *ttyn == '\0') {
+ (void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY);
+ ttyn = tname;
+ }
+ if (tty = strrchr(ttyn, '/'))
+ ++tty;
+ else
+ tty = ttyn;
+
+ for (cnt = 0;; ask = 1) {
+ if (ask) {
+ fflag = 0;
+ getloginname();
+ }
+ rootlogin = 0;
+#ifdef KERBEROS
+ if ((instance = strchr(username, '.')) != NULL) {
+ if (strncmp(instance, ".root", 5) == 0)
+ rootlogin = 1;
+ *instance++ = '\0';
+ } else
+ instance = "";
+#endif
+ if (strlen(username) > UT_NAMESIZE)
+ username[UT_NAMESIZE] = '\0';
+
+ /*
+ * Note if trying multiple user names; log failures for
+ * previous user name, but don't bother logging one failure
+ * for nonexistent name (mistyped username).
+ */
+ if (failures && strcmp(tbuf, username)) {
+ if (failures > (pwd ? 0 : 1))
+ badlogin(tbuf);
+ failures = 0;
+ }
+ (void)strcpy(tbuf, username);
+
+ if (pwd = getpwnam(username))
+ salt = pwd->pw_passwd;
+ else
+ salt = "xx";
+
+ /*
+ * if we have a valid account name, and it doesn't have a
+ * password, or the -f option was specified and the caller
+ * is root or the caller isn't changing their uid, don't
+ * authenticate.
+ */
+ if (pwd && (*pwd->pw_passwd == '\0' ||
+ fflag && (uid == 0 || uid == pwd->pw_uid)))
+ break;
+ fflag = 0;
+ if (pwd && pwd->pw_uid == 0)
+ rootlogin = 1;
+
+ (void)setpriority(PRIO_PROCESS, 0, -4);
+
+ p = getpass("Password:");
+
+ if (pwd) {
+#ifdef KERBEROS
+ rval = klogin(pwd, instance, localhost, p);
+ if (rval != 0 && rootlogin && pwd->pw_uid != 0)
+ rootlogin = 0;
+ if (rval == 0)
+ authok = 1;
+ else if (rval == 1)
+ rval = strcmp(crypt(p, salt), pwd->pw_passwd);
+#else
+ rval = strcmp(crypt(p, salt), pwd->pw_passwd);
+#endif
+ }
+ memset(p, 0, strlen(p));
+
+ (void)setpriority(PRIO_PROCESS, 0, 0);
+
+ /*
+ * If trying to log in as root without Kerberos,
+ * but with insecure terminal, refuse the login attempt.
+ */
+#ifdef KERBEROS
+ if (authok == 0)
+#endif
+ if (pwd && rootlogin && !rootterm(tty)) {
+ (void)fprintf(stderr,
+ "%s login refused on this terminal.\n",
+ pwd->pw_name);
+ if (hostname)
+ syslog(LOG_NOTICE,
+ "LOGIN %s REFUSED FROM %s ON TTY %s",
+ pwd->pw_name, hostname, tty);
+ else
+ syslog(LOG_NOTICE,
+ "LOGIN %s REFUSED ON TTY %s",
+ pwd->pw_name, tty);
+ continue;
+ }
+
+ if (pwd && !rval)
+ break;
+
+ (void)printf("Login incorrect\n");
+ failures++;
+ /* we allow 10 tries, but after 3 we start backing off */
+ if (++cnt > 3) {
+ if (cnt >= 10) {
+ badlogin(username);
+ sleepexit(1);
+ }
+ sleep((u_int)((cnt - 3) * 5));
+ }
+ }
+
+ /* committed to login -- turn off timeout */
+ (void)alarm((u_int)0);
+
+ endpwent();
+
+ /* if user not super-user, check for disabled logins */
+ if (!rootlogin)
+ checknologin();
+
+ if (chdir(pwd->pw_dir) < 0) {
+ (void)printf("No home directory %s!\n", pwd->pw_dir);
+ if (chdir("/"))
+ exit(0);
+ pwd->pw_dir = "/";
+ (void)printf("Logging in with home = \"/\".\n");
+ }
+
+ quietlog = access(_PATH_HUSHLOGIN, F_OK) == 0;
+
+ if (pwd->pw_change || pwd->pw_expire)
+ (void)gettimeofday(&tp, (struct timezone *)NULL);
+ if (pwd->pw_change)
+ if (tp.tv_sec >= pwd->pw_change) {
+ (void)printf("Sorry -- your password has expired.\n");
+ sleepexit(1);
+ } else if (pwd->pw_change - tp.tv_sec <
+ 2 * DAYSPERWEEK * SECSPERDAY && !quietlog)
+ (void)printf("Warning: your password expires on %s",
+ ctime(&pwd->pw_change));
+ if (pwd->pw_expire)
+ if (tp.tv_sec >= pwd->pw_expire) {
+ (void)printf("Sorry -- your account has expired.\n");
+ sleepexit(1);
+ } else if (pwd->pw_expire - tp.tv_sec <
+ 2 * DAYSPERWEEK * SECSPERDAY && !quietlog)
+ (void)printf("Warning: your account expires on %s",
+ ctime(&pwd->pw_expire));
+
+ /* Nothing else left to fail -- really log in. */
+ memset((void *)&utmp, 0, sizeof(utmp));
+ (void)time(&utmp.ut_time);
+ (void)strncpy(utmp.ut_name, username, sizeof(utmp.ut_name));
+ if (hostname)
+ (void)strncpy(utmp.ut_host, hostname, sizeof(utmp.ut_host));
+ (void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line));
+ login(&utmp);
+
+ dolastlog(quietlog);
+
+ (void)chown(ttyn, pwd->pw_uid,
+ (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid);
+ (void)setgid(pwd->pw_gid);
+
+ initgroups(username, pwd->pw_gid);
+
+ if (*pwd->pw_shell == '\0')
+ pwd->pw_shell = _PATH_BSHELL;
+
+ /* Destroy environment unless user has requested its preservation. */
+ if (!pflag)
+ environ = envinit;
+ (void)setenv("HOME", pwd->pw_dir, 1);
+ (void)setenv("SHELL", pwd->pw_shell, 1);
+ if (term[0] == '\0')
+ (void)strncpy(term, stypeof(tty), sizeof(term));
+ (void)setenv("TERM", term, 0);
+ (void)setenv("LOGNAME", pwd->pw_name, 1);
+ (void)setenv("USER", pwd->pw_name, 1);
+ (void)setenv("PATH", _PATH_DEFPATH, 0);
+#ifdef KERBEROS
+ if (krbtkfile_env)
+ (void)setenv("KRBTKFILE", krbtkfile_env, 1);
+#endif
+
+ if (tty[sizeof("tty")-1] == 'd')
+ syslog(LOG_INFO, "DIALUP %s, %s", tty, pwd->pw_name);
+
+ /* If fflag is on, assume caller/authenticator has logged root login. */
+ if (rootlogin && fflag == 0)
+ if (hostname)
+ syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s FROM %s",
+ username, tty, hostname);
+ else
+ syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s", username, tty);
+
+#ifdef KERBEROS
+ if (!quietlog && notickets == 1)
+ (void)printf("Warning: no Kerberos tickets issued.\n");
+#endif
+
+ if (!quietlog) {
+ (void)printf("%s\n\t%s %s\n\n",
+ "Copyright (c) 1980, 1983, 1986, 1988, 1990, 1991, 1993, 1994",
+ "The Regents of the University of California. ",
+ "All rights reserved.");
+ motd();
+ (void)snprintf(tbuf,
+ sizeof(tbuf), "%s/%s", _PATH_MAILDIR, pwd->pw_name);
+ if (stat(tbuf, &st) == 0 && st.st_size != 0)
+ (void)printf("You have %smail.\n",
+ (st.st_mtime > st.st_atime) ? "new " : "");
+ }
+
+ (void)signal(SIGALRM, SIG_DFL);
+ (void)signal(SIGQUIT, SIG_DFL);
+ (void)signal(SIGINT, SIG_DFL);
+ (void)signal(SIGTSTP, SIG_IGN);
+
+ tbuf[0] = '-';
+ (void)strcpy(tbuf + 1, (p = strrchr(pwd->pw_shell, '/')) ?
+ p + 1 : pwd->pw_shell);
+
+ if (setlogin(pwd->pw_name) < 0)
+ syslog(LOG_ERR, "setlogin() failure: %m");
+
+ /* Discard permissions last so can't get killed and drop core. */
+ if (rootlogin)
+ (void) setuid(0);
+ else
+ (void) setuid(pwd->pw_uid);
+
+ execlp(pwd->pw_shell, tbuf, 0);
+ err(1, "%s", pwd->pw_shell);
+}
+
+#ifdef KERBEROS
+#define NBUFSIZ (UT_NAMESIZE + 1 + 5) /* .root suffix */
+#else
+#define NBUFSIZ (UT_NAMESIZE + 1)
+#endif
+
+void
+getloginname()
+{
+ int ch;
+ char *p;
+ static char nbuf[NBUFSIZ];
+
+ for (;;) {
+ (void)printf("login: ");
+ for (p = nbuf; (ch = getchar()) != '\n'; ) {
+ if (ch == EOF) {
+ badlogin(username);
+ exit(0);
+ }
+ if (p < nbuf + (NBUFSIZ - 1))
+ *p++ = ch;
+ }
+ if (p > nbuf)
+ if (nbuf[0] == '-')
+ (void)fprintf(stderr,
+ "login names may not start with '-'.\n");
+ else {
+ *p = '\0';
+ username = nbuf;
+ break;
+ }
+ }
+}
+
+int
+rootterm(ttyn)
+ char *ttyn;
+{
+ struct ttyent *t;
+
+ return ((t = getttynam(ttyn)) && t->ty_status & TTY_SECURE);
+}
+
+jmp_buf motdinterrupt;
+
+void
+motd()
+{
+ int fd, nchars;
+ sig_t oldint;
+ char tbuf[8192];
+
+ if ((fd = open(_PATH_MOTDFILE, O_RDONLY, 0)) < 0)
+ return;
+ oldint = signal(SIGINT, sigint);
+ if (setjmp(motdinterrupt) == 0)
+ while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0)
+ (void)write(fileno(stdout), tbuf, nchars);
+ (void)signal(SIGINT, oldint);
+ (void)close(fd);
+}
+
+/* ARGSUSED */
+void
+sigint(signo)
+ int signo;
+{
+
+ longjmp(motdinterrupt, 1);
+}
+
+/* ARGSUSED */
+void
+timedout(signo)
+ int signo;
+{
+
+ (void)fprintf(stderr, "Login timed out after %d seconds\n", timeout);
+ exit(0);
+}
+
+void
+checknologin()
+{
+ int fd, nchars;
+ char tbuf[8192];
+
+ if ((fd = open(_PATH_NOLOGIN, O_RDONLY, 0)) >= 0) {
+ while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0)
+ (void)write(fileno(stdout), tbuf, nchars);
+ sleepexit(0);
+ }
+}
+
+void
+dolastlog(quiet)
+ int quiet;
+{
+ struct lastlog ll;
+ int fd;
+
+ if ((fd = open(_PATH_LASTLOG, O_RDWR, 0)) >= 0) {
+ (void)lseek(fd, (off_t)pwd->pw_uid * sizeof(ll), L_SET);
+ if (!quiet) {
+ if (read(fd, (char *)&ll, sizeof(ll)) == sizeof(ll) &&
+ ll.ll_time != 0) {
+ (void)printf("Last login: %.*s ",
+ 24-5, (char *)ctime(&ll.ll_time));
+ if (*ll.ll_host != '\0')
+ (void)printf("from %.*s\n",
+ (int)sizeof(ll.ll_host),
+ ll.ll_host);
+ else
+ (void)printf("on %.*s\n",
+ (int)sizeof(ll.ll_line),
+ ll.ll_line);
+ }
+ (void)lseek(fd, (off_t)pwd->pw_uid * sizeof(ll), L_SET);
+ }
+ memset((void *)&ll, 0, sizeof(ll));
+ (void)time(&ll.ll_time);
+ (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line));
+ if (hostname)
+ (void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host));
+ (void)write(fd, (char *)&ll, sizeof(ll));
+ (void)close(fd);
+ }
+}
+
+void
+badlogin(name)
+ char *name;
+{
+
+ if (failures == 0)
+ return;
+ if (hostname) {
+ syslog(LOG_NOTICE, "%d LOGIN FAILURE%s FROM %s",
+ failures, failures > 1 ? "S" : "", hostname);
+ syslog(LOG_AUTHPRIV|LOG_NOTICE,
+ "%d LOGIN FAILURE%s FROM %s, %s",
+ failures, failures > 1 ? "S" : "", hostname, name);
+ } else {
+ syslog(LOG_NOTICE, "%d LOGIN FAILURE%s ON %s",
+ failures, failures > 1 ? "S" : "", tty);
+ syslog(LOG_AUTHPRIV|LOG_NOTICE,
+ "%d LOGIN FAILURE%s ON %s, %s",
+ failures, failures > 1 ? "S" : "", tty, name);
+ }
+}
+
+#undef UNKNOWN
+#define UNKNOWN "su"
+
+char *
+stypeof(ttyid)
+ char *ttyid;
+{
+ struct ttyent *t;
+
+ return (ttyid && (t = getttynam(ttyid)) ? t->ty_type : UNKNOWN);
+}
+
+void
+sleepexit(eval)
+ int eval;
+{
+
+ (void)sleep(5);
+ exit(eval);
+}
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