5ee7cd2107
Approved by: re (kensmith)
852 lines
21 KiB
C
852 lines
21 KiB
C
/* $OpenBSD: authpf.c,v 1.104 2007/02/24 17:35:08 beck Exp $ */
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/*
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* Copyright (C) 1998 - 2007 Bob Beck (beck@openbsd.org).
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*
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* Permission to use, copy, modify, and distribute this software for any
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* purpose with or without fee is hereby granted, provided that the above
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* copyright notice and this permission notice appear in all copies.
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*
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* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
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* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
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* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include <sys/param.h>
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#include <sys/file.h>
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#include <sys/ioctl.h>
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#include <sys/socket.h>
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#include <sys/stat.h>
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#include <sys/time.h>
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#include <sys/wait.h>
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#include <net/if.h>
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#include <net/pfvar.h>
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#include <arpa/inet.h>
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#include <err.h>
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#include <errno.h>
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#ifdef __FreeBSD__
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#include <inttypes.h>
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#endif
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#include <login_cap.h>
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#include <pwd.h>
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#include <signal.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <syslog.h>
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#include <unistd.h>
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#include "pathnames.h"
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static int read_config(FILE *);
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static void print_message(char *);
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static int allowed_luser(char *);
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static int check_luser(char *, char *);
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static int remove_stale_rulesets(void);
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static int change_filter(int, const char *, const char *);
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static int change_table(int, const char *);
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static void authpf_kill_states(void);
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int dev; /* pf device */
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char anchorname[PF_ANCHOR_NAME_SIZE] = "authpf";
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char rulesetname[MAXPATHLEN - PF_ANCHOR_NAME_SIZE - 2];
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char tablename[PF_TABLE_NAME_SIZE] = "authpf_users";
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FILE *pidfp;
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char luser[MAXLOGNAME]; /* username */
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char ipsrc[256]; /* ip as a string */
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char pidfile[MAXPATHLEN]; /* we save pid in this file. */
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struct timeval Tstart, Tend; /* start and end times of session */
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volatile sig_atomic_t want_death;
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static void need_death(int signo);
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#ifdef __FreeBSD__
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static __dead2 void do_death(int);
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#else
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static __dead void do_death(int);
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#endif
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/*
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* User shell for authenticating gateways. Sole purpose is to allow
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* a user to ssh to a gateway, and have the gateway modify packet
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* filters to allow access, then remove access when the user finishes
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* up. Meant to be used only from ssh(1) connections.
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*/
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int
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main(int argc, char *argv[])
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{
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int lockcnt = 0, n, pidfd;
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FILE *config;
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struct in6_addr ina;
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struct passwd *pw;
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char *cp;
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gid_t gid;
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uid_t uid;
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char *shell;
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login_cap_t *lc;
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config = fopen(PATH_CONFFILE, "r");
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if (config == NULL) {
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syslog(LOG_ERR, "can not open %s (%m)", PATH_CONFFILE);
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exit(1);
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}
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if ((cp = getenv("SSH_TTY")) == NULL) {
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syslog(LOG_ERR, "non-interactive session connection for authpf");
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exit(1);
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}
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if ((cp = getenv("SSH_CLIENT")) == NULL) {
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syslog(LOG_ERR, "cannot determine connection source");
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exit(1);
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}
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if (strlcpy(ipsrc, cp, sizeof(ipsrc)) >= sizeof(ipsrc)) {
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syslog(LOG_ERR, "SSH_CLIENT variable too long");
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exit(1);
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}
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cp = strchr(ipsrc, ' ');
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if (!cp) {
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syslog(LOG_ERR, "corrupt SSH_CLIENT variable %s", ipsrc);
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exit(1);
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}
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*cp = '\0';
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if (inet_pton(AF_INET, ipsrc, &ina) != 1 &&
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inet_pton(AF_INET6, ipsrc, &ina) != 1) {
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syslog(LOG_ERR,
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"cannot determine IP from SSH_CLIENT %s", ipsrc);
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exit(1);
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}
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/* open the pf device */
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dev = open(PATH_DEVFILE, O_RDWR);
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if (dev == -1) {
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syslog(LOG_ERR, "cannot open packet filter device (%m)");
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goto die;
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}
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uid = getuid();
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pw = getpwuid(uid);
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if (pw == NULL) {
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syslog(LOG_ERR, "cannot find user for uid %u", uid);
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goto die;
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}
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if ((lc = login_getclass(pw->pw_class)) != NULL)
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shell = (char *)login_getcapstr(lc, "shell", pw->pw_shell,
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pw->pw_shell);
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else
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shell = pw->pw_shell;
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login_close(lc);
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if (strcmp(shell, PATH_AUTHPF_SHELL)) {
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syslog(LOG_ERR, "wrong shell for user %s, uid %u",
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pw->pw_name, pw->pw_uid);
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if (shell != pw->pw_shell)
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free(shell);
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goto die;
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}
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if (shell != pw->pw_shell)
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free(shell);
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/*
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* Paranoia, but this data _does_ come from outside authpf, and
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* truncation would be bad.
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*/
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if (strlcpy(luser, pw->pw_name, sizeof(luser)) >= sizeof(luser)) {
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syslog(LOG_ERR, "username too long: %s", pw->pw_name);
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goto die;
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}
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if ((n = snprintf(rulesetname, sizeof(rulesetname), "%s(%ld)",
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luser, (long)getpid())) < 0 || (u_int)n >= sizeof(rulesetname)) {
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syslog(LOG_INFO, "%s(%ld) too large, ruleset name will be %ld",
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luser, (long)getpid(), (long)getpid());
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if ((n = snprintf(rulesetname, sizeof(rulesetname), "%ld",
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(long)getpid())) < 0 || (u_int)n >= sizeof(rulesetname)) {
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syslog(LOG_ERR, "pid too large for ruleset name");
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goto die;
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}
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}
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/* Make our entry in /var/authpf as /var/authpf/ipaddr */
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n = snprintf(pidfile, sizeof(pidfile), "%s/%s", PATH_PIDFILE, ipsrc);
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if (n < 0 || (u_int)n >= sizeof(pidfile)) {
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syslog(LOG_ERR, "path to pidfile too long");
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goto die;
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}
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/*
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* If someone else is already using this ip, then this person
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* wants to switch users - so kill the old process and exit
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* as well.
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*
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* Note, we could print a message and tell them to log out, but the
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* usual case of this is that someone has left themselves logged in,
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* with the authenticated connection iconized and someone else walks
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* up to use and automatically logs in before using. If this just
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* gets rid of the old one silently, the new user never knows they
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* could have used someone else's old authentication. If we
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* tell them to log out before switching users it is an invitation
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* for abuse.
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*/
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do {
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int save_errno, otherpid = -1;
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char otherluser[MAXLOGNAME];
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if ((pidfd = open(pidfile, O_RDWR|O_CREAT, 0644)) == -1 ||
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(pidfp = fdopen(pidfd, "r+")) == NULL) {
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if (pidfd != -1)
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close(pidfd);
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syslog(LOG_ERR, "cannot open or create %s: %s", pidfile,
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strerror(errno));
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goto die;
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}
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if (flock(fileno(pidfp), LOCK_EX|LOCK_NB) == 0)
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break;
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save_errno = errno;
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/* Mark our pid, and username to our file. */
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rewind(pidfp);
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/* 31 == MAXLOGNAME - 1 */
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if (fscanf(pidfp, "%d\n%31s\n", &otherpid, otherluser) != 2)
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otherpid = -1;
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syslog(LOG_DEBUG, "tried to lock %s, in use by pid %d: %s",
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pidfile, otherpid, strerror(save_errno));
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if (otherpid > 0) {
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syslog(LOG_INFO,
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"killing prior auth (pid %d) of %s by user %s",
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otherpid, ipsrc, otherluser);
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if (kill((pid_t) otherpid, SIGTERM) == -1) {
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syslog(LOG_INFO,
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"could not kill process %d: (%m)",
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otherpid);
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}
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}
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/*
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* we try to kill the previous process and acquire the lock
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* for 10 seconds, trying once a second. if we can't after
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* 10 attempts we log an error and give up
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*/
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if (++lockcnt > 10) {
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syslog(LOG_ERR, "cannot kill previous authpf (pid %d)",
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otherpid);
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fclose(pidfp);
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pidfp = NULL;
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goto dogdeath;
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}
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sleep(1);
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/* re-open, and try again. The previous authpf process
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* we killed above should unlink the file and release
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* it's lock, giving us a chance to get it now
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*/
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fclose(pidfp);
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pidfp = NULL;
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} while (1);
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/* whack the group list */
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gid = getegid();
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if (setgroups(1, &gid) == -1) {
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syslog(LOG_INFO, "setgroups: %s", strerror(errno));
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do_death(0);
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}
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/* revoke privs */
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uid = getuid();
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if (setresuid(uid, uid, uid) == -1) {
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syslog(LOG_INFO, "setresuid: %s", strerror(errno));
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do_death(0);
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}
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openlog("authpf", LOG_PID | LOG_NDELAY, LOG_DAEMON);
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if (!check_luser(PATH_BAN_DIR, luser) || !allowed_luser(luser)) {
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syslog(LOG_INFO, "user %s prohibited", luser);
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do_death(0);
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}
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if (read_config(config)) {
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syslog(LOG_ERR, "invalid config file %s", PATH_CONFFILE);
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do_death(0);
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}
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if (remove_stale_rulesets()) {
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syslog(LOG_INFO, "error removing stale rulesets");
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do_death(0);
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}
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/* We appear to be making headway, so actually mark our pid */
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rewind(pidfp);
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fprintf(pidfp, "%ld\n%s\n", (long)getpid(), luser);
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fflush(pidfp);
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(void) ftruncate(fileno(pidfp), ftello(pidfp));
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if (change_filter(1, luser, ipsrc) == -1) {
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printf("Unable to modify filters\r\n");
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do_death(0);
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}
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if (change_table(1, ipsrc) == -1) {
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printf("Unable to modify table\r\n");
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change_filter(0, luser, ipsrc);
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do_death(0);
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}
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signal(SIGTERM, need_death);
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signal(SIGINT, need_death);
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signal(SIGALRM, need_death);
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signal(SIGPIPE, need_death);
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signal(SIGHUP, need_death);
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signal(SIGQUIT, need_death);
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signal(SIGTSTP, need_death);
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while (1) {
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printf("\r\nHello %s. ", luser);
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printf("You are authenticated from host \"%s\"\r\n", ipsrc);
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setproctitle("%s@%s", luser, ipsrc);
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print_message(PATH_MESSAGE);
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while (1) {
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sleep(10);
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if (want_death)
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do_death(1);
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}
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}
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/* NOTREACHED */
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dogdeath:
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printf("\r\n\r\nSorry, this service is currently unavailable due to ");
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printf("technical difficulties\r\n\r\n");
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print_message(PATH_PROBLEM);
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printf("\r\nYour authentication process (pid %ld) was unable to run\n",
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(long)getpid());
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sleep(180); /* them lusers read reaaaaal slow */
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die:
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do_death(0);
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/* NOTREACHED */
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}
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/*
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* reads config file in PATH_CONFFILE to set optional behaviours up
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*/
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static int
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read_config(FILE *f)
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{
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char buf[1024];
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int i = 0;
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do {
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char **ap;
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char *pair[4], *cp, *tp;
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int len;
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if (fgets(buf, sizeof(buf), f) == NULL) {
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fclose(f);
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return (0);
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}
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i++;
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len = strlen(buf);
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if (buf[len - 1] != '\n' && !feof(f)) {
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syslog(LOG_ERR, "line %d too long in %s", i,
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PATH_CONFFILE);
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return (1);
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}
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buf[len - 1] = '\0';
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for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
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; /* nothing */
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if (!*cp || *cp == '#' || *cp == '\n')
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continue;
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for (ap = pair; ap < &pair[3] &&
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(*ap = strsep(&cp, "=")) != NULL; ) {
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if (**ap != '\0')
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ap++;
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}
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if (ap != &pair[2])
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goto parse_error;
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tp = pair[1] + strlen(pair[1]);
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while ((*tp == ' ' || *tp == '\t') && tp >= pair[1])
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*tp-- = '\0';
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if (strcasecmp(pair[0], "anchor") == 0) {
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if (!pair[1][0] || strlcpy(anchorname, pair[1],
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sizeof(anchorname)) >= sizeof(anchorname))
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goto parse_error;
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}
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if (strcasecmp(pair[0], "table") == 0) {
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if (!pair[1][0] || strlcpy(tablename, pair[1],
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sizeof(tablename)) >= sizeof(tablename))
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goto parse_error;
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}
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} while (!feof(f) && !ferror(f));
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fclose(f);
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return (0);
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parse_error:
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fclose(f);
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syslog(LOG_ERR, "parse error, line %d of %s", i, PATH_CONFFILE);
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return (1);
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}
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/*
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* splatter a file to stdout - max line length of 1024,
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* used for spitting message files at users to tell them
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* they've been bad or we're unavailable.
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*/
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static void
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print_message(char *filename)
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{
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char buf[1024];
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FILE *f;
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if ((f = fopen(filename, "r")) == NULL)
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return; /* fail silently, we don't care if it isn't there */
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do {
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if (fgets(buf, sizeof(buf), f) == NULL) {
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fflush(stdout);
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fclose(f);
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return;
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}
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} while (fputs(buf, stdout) != EOF && !feof(f));
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fflush(stdout);
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fclose(f);
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}
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/*
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* allowed_luser checks to see if user "luser" is allowed to
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* use this gateway by virtue of being listed in an allowed
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* users file, namely /etc/authpf/authpf.allow .
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*
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* If /etc/authpf/authpf.allow does not exist, then we assume that
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* all users who are allowed in by sshd(8) are permitted to
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* use this gateway. If /etc/authpf/authpf.allow does exist, then a
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* user must be listed if the connection is to continue, else
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* the session terminates in the same manner as being banned.
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*/
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static int
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allowed_luser(char *luser)
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{
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char *buf, *lbuf;
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int matched;
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size_t len;
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FILE *f;
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if ((f = fopen(PATH_ALLOWFILE, "r")) == NULL) {
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if (errno == ENOENT) {
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/*
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* allowfile doesn't exist, thus this gateway
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* isn't restricted to certain users...
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*/
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return (1);
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}
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/*
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* luser may in fact be allowed, but we can't open
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* the file even though it's there. probably a config
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* problem.
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*/
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syslog(LOG_ERR, "cannot open allowed users file %s (%s)",
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PATH_ALLOWFILE, strerror(errno));
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return (0);
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} else {
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/*
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* /etc/authpf/authpf.allow exists, thus we do a linear
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* search to see if they are allowed.
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* also, if username "*" exists, then this is a
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* "public" gateway, such as it is, so let
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* everyone use it.
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*/
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lbuf = NULL;
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while ((buf = fgetln(f, &len))) {
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if (buf[len - 1] == '\n')
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buf[len - 1] = '\0';
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else {
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if ((lbuf = (char *)malloc(len + 1)) == NULL)
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err(1, NULL);
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memcpy(lbuf, buf, len);
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lbuf[len] = '\0';
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buf = lbuf;
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}
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matched = strcmp(luser, buf) == 0 || strcmp("*", buf) == 0;
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if (lbuf != NULL) {
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free(lbuf);
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lbuf = NULL;
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}
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if (matched)
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return (1); /* matched an allowed username */
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}
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syslog(LOG_INFO, "denied access to %s: not listed in %s",
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luser, PATH_ALLOWFILE);
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/* reuse buf */
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buf = "\n\nSorry, you are not allowed to use this facility!\n";
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fputs(buf, stdout);
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}
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fflush(stdout);
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return (0);
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}
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/*
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* check_luser checks to see if user "luser" has been banned
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* from using us by virtue of having an file of the same name
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* in the "luserdir" directory.
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|
*
|
|
* If the user has been banned, we copy the contents of the file
|
|
* to the user's screen. (useful for telling the user what to
|
|
* do to get un-banned, or just to tell them they aren't
|
|
* going to be un-banned.)
|
|
*/
|
|
static int
|
|
check_luser(char *luserdir, char *luser)
|
|
{
|
|
FILE *f;
|
|
int n;
|
|
char tmp[MAXPATHLEN];
|
|
|
|
n = snprintf(tmp, sizeof(tmp), "%s/%s", luserdir, luser);
|
|
if (n < 0 || (u_int)n >= sizeof(tmp)) {
|
|
syslog(LOG_ERR, "provided banned directory line too long (%s)",
|
|
luserdir);
|
|
return (0);
|
|
}
|
|
if ((f = fopen(tmp, "r")) == NULL) {
|
|
if (errno == ENOENT) {
|
|
/*
|
|
* file or dir doesn't exist, so therefore
|
|
* this luser isn't banned.. all is well
|
|
*/
|
|
return (1);
|
|
} else {
|
|
/*
|
|
* luser may in fact be banned, but we can't open the
|
|
* file even though it's there. probably a config
|
|
* problem.
|
|
*/
|
|
syslog(LOG_ERR, "cannot open banned file %s (%s)",
|
|
tmp, strerror(errno));
|
|
return (0);
|
|
}
|
|
} else {
|
|
/*
|
|
* luser is banned - spit the file at them to
|
|
* tell what they can do and where they can go.
|
|
*/
|
|
syslog(LOG_INFO, "denied access to %s: %s exists",
|
|
luser, tmp);
|
|
|
|
/* reuse tmp */
|
|
strlcpy(tmp, "\n\n-**- Sorry, you have been banned! -**-\n\n",
|
|
sizeof(tmp));
|
|
while (fputs(tmp, stdout) != EOF && !feof(f)) {
|
|
if (fgets(tmp, sizeof(tmp), f) == NULL) {
|
|
fflush(stdout);
|
|
fclose(f);
|
|
return (0);
|
|
}
|
|
}
|
|
fclose(f);
|
|
}
|
|
fflush(stdout);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Search for rulesets left by other authpf processes (either because they
|
|
* died ungracefully or were terminated) and remove them.
|
|
*/
|
|
static int
|
|
remove_stale_rulesets(void)
|
|
{
|
|
struct pfioc_ruleset prs;
|
|
u_int32_t nr, mnr;
|
|
|
|
memset(&prs, 0, sizeof(prs));
|
|
strlcpy(prs.path, anchorname, sizeof(prs.path));
|
|
if (ioctl(dev, DIOCGETRULESETS, &prs)) {
|
|
if (errno == EINVAL)
|
|
return (0);
|
|
else
|
|
return (1);
|
|
}
|
|
|
|
mnr = prs.nr;
|
|
nr = 0;
|
|
while (nr < mnr) {
|
|
char *s, *t;
|
|
pid_t pid;
|
|
|
|
prs.nr = nr;
|
|
if (ioctl(dev, DIOCGETRULESET, &prs))
|
|
return (1);
|
|
errno = 0;
|
|
if ((t = strchr(prs.name, '(')) == NULL)
|
|
t = prs.name;
|
|
else
|
|
t++;
|
|
pid = strtoul(t, &s, 10);
|
|
if (!prs.name[0] || errno ||
|
|
(*s && (t == prs.name || *s != ')')))
|
|
return (1);
|
|
if (kill(pid, 0) && errno != EPERM) {
|
|
int i;
|
|
struct pfioc_trans_e t_e[PF_RULESET_MAX+1];
|
|
struct pfioc_trans t;
|
|
|
|
bzero(&t, sizeof(t));
|
|
bzero(t_e, sizeof(t_e));
|
|
t.size = PF_RULESET_MAX+1;
|
|
t.esize = sizeof(t_e[0]);
|
|
t.array = t_e;
|
|
for (i = 0; i < PF_RULESET_MAX+1; ++i) {
|
|
t_e[i].rs_num = i;
|
|
snprintf(t_e[i].anchor, sizeof(t_e[i].anchor),
|
|
"%s/%s", anchorname, prs.name);
|
|
}
|
|
t_e[PF_RULESET_MAX].rs_num = PF_RULESET_TABLE;
|
|
if ((ioctl(dev, DIOCXBEGIN, &t) ||
|
|
ioctl(dev, DIOCXCOMMIT, &t)) &&
|
|
errno != EINVAL)
|
|
return (1);
|
|
mnr--;
|
|
} else
|
|
nr++;
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Add/remove filter entries for user "luser" from ip "ipsrc"
|
|
*/
|
|
static int
|
|
change_filter(int add, const char *luser, const char *ipsrc)
|
|
{
|
|
char *pargv[13] = {
|
|
"pfctl", "-p", "/dev/pf", "-q", "-a", "anchor/ruleset",
|
|
"-D", "user_ip=X", "-D", "user_id=X", "-f",
|
|
"file", NULL
|
|
};
|
|
char *fdpath = NULL, *userstr = NULL, *ipstr = NULL;
|
|
char *rsn = NULL, *fn = NULL;
|
|
pid_t pid;
|
|
gid_t gid;
|
|
int s;
|
|
|
|
if (luser == NULL || !luser[0] || ipsrc == NULL || !ipsrc[0]) {
|
|
syslog(LOG_ERR, "invalid luser/ipsrc");
|
|
goto error;
|
|
}
|
|
|
|
if (asprintf(&rsn, "%s/%s", anchorname, rulesetname) == -1)
|
|
goto no_mem;
|
|
if (asprintf(&fdpath, "/dev/fd/%d", dev) == -1)
|
|
goto no_mem;
|
|
if (asprintf(&ipstr, "user_ip=%s", ipsrc) == -1)
|
|
goto no_mem;
|
|
if (asprintf(&userstr, "user_id=%s", luser) == -1)
|
|
goto no_mem;
|
|
|
|
if (add) {
|
|
struct stat sb;
|
|
|
|
if (asprintf(&fn, "%s/%s/authpf.rules", PATH_USER_DIR, luser)
|
|
== -1)
|
|
goto no_mem;
|
|
if (stat(fn, &sb) == -1) {
|
|
free(fn);
|
|
if ((fn = strdup(PATH_PFRULES)) == NULL)
|
|
goto no_mem;
|
|
}
|
|
}
|
|
pargv[2] = fdpath;
|
|
pargv[5] = rsn;
|
|
pargv[7] = userstr;
|
|
pargv[9] = ipstr;
|
|
if (!add)
|
|
pargv[11] = "/dev/null";
|
|
else
|
|
pargv[11] = fn;
|
|
|
|
switch (pid = fork()) {
|
|
case -1:
|
|
syslog(LOG_ERR, "fork failed");
|
|
goto error;
|
|
case 0:
|
|
/* revoke group privs before exec */
|
|
gid = getgid();
|
|
if (setregid(gid, gid) == -1) {
|
|
err(1, "setregid");
|
|
}
|
|
execvp(PATH_PFCTL, pargv);
|
|
warn("exec of %s failed", PATH_PFCTL);
|
|
_exit(1);
|
|
}
|
|
|
|
/* parent */
|
|
waitpid(pid, &s, 0);
|
|
if (s != 0) {
|
|
syslog(LOG_ERR, "pfctl exited abnormally");
|
|
goto error;
|
|
}
|
|
|
|
if (add) {
|
|
gettimeofday(&Tstart, NULL);
|
|
syslog(LOG_INFO, "allowing %s, user %s", ipsrc, luser);
|
|
} else {
|
|
gettimeofday(&Tend, NULL);
|
|
#ifdef __FreeBSD__
|
|
syslog(LOG_INFO, "removed %s, user %s - duration %jd seconds",
|
|
ipsrc, luser, (intmax_t)(Tend.tv_sec - Tstart.tv_sec));
|
|
#else
|
|
syslog(LOG_INFO, "removed %s, user %s - duration %ld seconds",
|
|
ipsrc, luser, Tend.tv_sec - Tstart.tv_sec);
|
|
#endif
|
|
}
|
|
return (0);
|
|
no_mem:
|
|
syslog(LOG_ERR, "malloc failed");
|
|
error:
|
|
free(fdpath);
|
|
free(rsn);
|
|
free(userstr);
|
|
free(ipstr);
|
|
free(fn);
|
|
return (-1);
|
|
}
|
|
|
|
/*
|
|
* Add/remove this IP from the "authpf_users" table.
|
|
*/
|
|
static int
|
|
change_table(int add, const char *ipsrc)
|
|
{
|
|
struct pfioc_table io;
|
|
struct pfr_addr addr;
|
|
|
|
bzero(&io, sizeof(io));
|
|
strlcpy(io.pfrio_table.pfrt_name, tablename,
|
|
sizeof(io.pfrio_table.pfrt_name));
|
|
io.pfrio_buffer = &addr;
|
|
io.pfrio_esize = sizeof(addr);
|
|
io.pfrio_size = 1;
|
|
|
|
bzero(&addr, sizeof(addr));
|
|
if (ipsrc == NULL || !ipsrc[0])
|
|
return (-1);
|
|
if (inet_pton(AF_INET, ipsrc, &addr.pfra_ip4addr) == 1) {
|
|
addr.pfra_af = AF_INET;
|
|
addr.pfra_net = 32;
|
|
} else if (inet_pton(AF_INET6, ipsrc, &addr.pfra_ip6addr) == 1) {
|
|
addr.pfra_af = AF_INET6;
|
|
addr.pfra_net = 128;
|
|
} else {
|
|
syslog(LOG_ERR, "invalid ipsrc");
|
|
return (-1);
|
|
}
|
|
|
|
if (ioctl(dev, add ? DIOCRADDADDRS : DIOCRDELADDRS, &io) &&
|
|
errno != ESRCH) {
|
|
syslog(LOG_ERR, "cannot %s %s from table %s: %s",
|
|
add ? "add" : "remove", ipsrc, tablename,
|
|
strerror(errno));
|
|
return (-1);
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* This is to kill off states that would otherwise be left behind stateful
|
|
* rules. This means we don't need to allow in more traffic than we really
|
|
* want to, since we don't have to worry about any luser sessions lasting
|
|
* longer than their ssh session. This function is based on
|
|
* pfctl_kill_states from pfctl.
|
|
*/
|
|
static void
|
|
authpf_kill_states(void)
|
|
{
|
|
struct pfioc_state_kill psk;
|
|
struct pf_addr target;
|
|
|
|
memset(&psk, 0, sizeof(psk));
|
|
memset(&target, 0, sizeof(target));
|
|
|
|
if (inet_pton(AF_INET, ipsrc, &target.v4) == 1)
|
|
psk.psk_af = AF_INET;
|
|
else if (inet_pton(AF_INET6, ipsrc, &target.v6) == 1)
|
|
psk.psk_af = AF_INET6;
|
|
else {
|
|
syslog(LOG_ERR, "inet_pton(%s) failed", ipsrc);
|
|
return;
|
|
}
|
|
|
|
/* Kill all states from ipsrc */
|
|
memcpy(&psk.psk_src.addr.v.a.addr, &target,
|
|
sizeof(psk.psk_src.addr.v.a.addr));
|
|
memset(&psk.psk_src.addr.v.a.mask, 0xff,
|
|
sizeof(psk.psk_src.addr.v.a.mask));
|
|
if (ioctl(dev, DIOCKILLSTATES, &psk))
|
|
syslog(LOG_ERR, "DIOCKILLSTATES failed (%m)");
|
|
|
|
/* Kill all states to ipsrc */
|
|
memset(&psk.psk_src, 0, sizeof(psk.psk_src));
|
|
memcpy(&psk.psk_dst.addr.v.a.addr, &target,
|
|
sizeof(psk.psk_dst.addr.v.a.addr));
|
|
memset(&psk.psk_dst.addr.v.a.mask, 0xff,
|
|
sizeof(psk.psk_dst.addr.v.a.mask));
|
|
if (ioctl(dev, DIOCKILLSTATES, &psk))
|
|
syslog(LOG_ERR, "DIOCKILLSTATES failed (%m)");
|
|
}
|
|
|
|
/* signal handler that makes us go away properly */
|
|
static void
|
|
need_death(int signo)
|
|
{
|
|
want_death = 1;
|
|
}
|
|
|
|
/*
|
|
* function that removes our stuff when we go away.
|
|
*/
|
|
#ifdef __FreeBSD__
|
|
static __dead2 void
|
|
#else
|
|
static __dead void
|
|
#endif
|
|
do_death(int active)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (active) {
|
|
change_filter(0, luser, ipsrc);
|
|
change_table(0, ipsrc);
|
|
authpf_kill_states();
|
|
remove_stale_rulesets();
|
|
}
|
|
if (pidfile[0] && (pidfp != NULL))
|
|
if (unlink(pidfile) == -1)
|
|
syslog(LOG_ERR, "cannot unlink %s (%m)", pidfile);
|
|
exit(ret);
|
|
}
|