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-rw-r--r--modules/pam_filter/pam_filter.c744
1 files changed, 0 insertions, 744 deletions
diff --git a/modules/pam_filter/pam_filter.c b/modules/pam_filter/pam_filter.c
deleted file mode 100644
index 86bc172b..00000000
--- a/modules/pam_filter/pam_filter.c
+++ /dev/null
@@ -1,744 +0,0 @@
-/*
- * $Id$
- *
- * written by Andrew Morgan <morgan@transmeta.com> with much help from
- * Richard Stevens' UNIX Network Programming book.
- */
-
-#include "config.h"
-
-#include <stdlib.h>
-#include <syslog.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <string.h>
-
-#include <stdio.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <sys/time.h>
-#include <sys/file.h>
-#include <sys/stat.h>
-#include <sys/socket.h>
-#include <sys/ioctl.h>
-#include <termios.h>
-
-#include <signal.h>
-
-#define PAM_SM_AUTH
-#define PAM_SM_ACCOUNT
-#define PAM_SM_SESSION
-#define PAM_SM_PASSWORD
-
-#include <security/pam_modules.h>
-#include <security/pam_ext.h>
-#include "pam_filter.h"
-
-/* ------ some tokens used for convenience throughout this file ------- */
-
-#define FILTER_DEBUG 01
-#define FILTER_RUN1 02
-#define FILTER_RUN2 04
-#define NEW_TERM 010
-#define NON_TERM 020
-
-/* -------------------------------------------------------------------- */
-
-/* log errors */
-
-#include <stdarg.h>
-
-#define TERMINAL_LEN 12
-
-static int
-master (const pam_handle_t *pamh, char *terminal)
-/*
- * try to open all of the terminals in sequence return first free one,
- * or -1
- */
-{
- const char ptys[] = "pqrs", *pty = ptys;
- const char hexs[] = "0123456789abcdef", *hex;
- struct stat tstat;
- int fd;
-
- strcpy(terminal, "/dev/pty??");
-
- while (*pty) { /* step through four types */
- terminal[8] = *pty++;
- terminal[9] = '0';
- if (stat(terminal,&tstat) < 0) {
- pam_syslog(pamh, LOG_WARNING,
- "unknown pseudo terminal: %s", terminal);
- break;
- }
- for (hex = hexs; *hex; ) { /* step through 16 of these */
- terminal[9] = *hex++;
- if ((fd = open(terminal, O_RDWR)) >= 0) {
- return fd;
- }
- }
- }
-
- /* no terminal found */
-
- return -1;
-}
-
-static int process_args(pam_handle_t *pamh
- , int argc, const char **argv, const char *type
- , char ***evp, const char **filtername)
-{
- int ctrl=0;
-
- while (argc-- > 0) {
- if (strcmp("debug",*argv) == 0) {
- ctrl |= FILTER_DEBUG;
- } else if (strcmp("new_term",*argv) == 0) {
- ctrl |= NEW_TERM;
- } else if (strcmp("non_term",*argv) == 0) {
- ctrl |= NON_TERM;
- } else if (strcmp("run1",*argv) == 0) {
- ctrl |= FILTER_RUN1;
- if (argc <= 0) {
- pam_syslog(pamh, LOG_ALERT, "no run filter supplied");
- } else
- break;
- } else if (strcmp("run2",*argv) == 0) {
- ctrl |= FILTER_RUN2;
- if (argc <= 0) {
- pam_syslog(pamh, LOG_ALERT, "no run filter supplied");
- } else
- break;
- } else {
- pam_syslog(pamh, LOG_ERR, "unrecognized option: %s", *argv);
- }
- ++argv; /* step along list */
- }
-
- if (argc < 0) {
- /* there was no reference to a filter */
- *filtername = NULL;
- *evp = NULL;
- } else {
- char **levp;
- const char *user = NULL;
- const void *tmp;
- int i,size, retval;
-
- *filtername = *++argv;
- if (ctrl & FILTER_DEBUG) {
- pam_syslog(pamh, LOG_DEBUG, "will run filter %s", *filtername);
- }
-
- levp = (char **) malloc(5*sizeof(char *));
- if (levp == NULL) {
- pam_syslog(pamh, LOG_CRIT, "no memory for environment of filter");
- return -1;
- }
-
- for (size=i=0; i<argc; ++i) {
- size += strlen(argv[i])+1;
- }
-
- /* the "ARGS" variable */
-
-#define ARGS_OFFSET 5 /* strlen('ARGS='); */
-#define ARGS_NAME "ARGS="
-
- size += ARGS_OFFSET;
-
- levp[0] = (char *) malloc(size);
- if (levp[0] == NULL) {
- pam_syslog(pamh, LOG_CRIT, "no memory for filter arguments");
- if (levp) {
- free(levp);
- }
- return -1;
- }
-
- strncpy(levp[0],ARGS_NAME,ARGS_OFFSET);
- for (i=0,size=ARGS_OFFSET; i<argc; ++i) {
- strcpy(levp[0]+size, argv[i]);
- size += strlen(argv[i]);
- levp[0][size++] = ' ';
- }
- levp[0][--size] = '\0'; /* <NUL> terminate */
-
- /* the "SERVICE" variable */
-
-#define SERVICE_OFFSET 8 /* strlen('SERVICE='); */
-#define SERVICE_NAME "SERVICE="
-
- retval = pam_get_item(pamh, PAM_SERVICE, &tmp);
- if (retval != PAM_SUCCESS || tmp == NULL) {
- pam_syslog(pamh, LOG_CRIT, "service name not found");
- if (levp) {
- free(levp[0]);
- free(levp);
- }
- return -1;
- }
- size = SERVICE_OFFSET+strlen(tmp);
-
- levp[1] = (char *) malloc(size+1);
- if (levp[1] == NULL) {
- pam_syslog(pamh, LOG_CRIT, "no memory for service name");
- if (levp) {
- free(levp[0]);
- free(levp);
- }
- return -1;
- }
-
- strncpy(levp[1],SERVICE_NAME,SERVICE_OFFSET);
- strcpy(levp[1]+SERVICE_OFFSET, tmp);
- levp[1][size] = '\0'; /* <NUL> terminate */
-
- /* the "USER" variable */
-
-#define USER_OFFSET 5 /* strlen('USER='); */
-#define USER_NAME "USER="
-
- pam_get_user(pamh, &user, NULL);
- if (user == NULL) {
- user = "<unknown>";
- }
- size = USER_OFFSET+strlen(user);
-
- levp[2] = (char *) malloc(size+1);
- if (levp[2] == NULL) {
- pam_syslog(pamh, LOG_CRIT, "no memory for user's name");
- if (levp) {
- free(levp[1]);
- free(levp[0]);
- free(levp);
- }
- return -1;
- }
-
- strncpy(levp[2],USER_NAME,USER_OFFSET);
- strcpy(levp[2]+USER_OFFSET, user);
- levp[2][size] = '\0'; /* <NUL> terminate */
-
- /* the "USER" variable */
-
-#define TYPE_OFFSET 5 /* strlen('TYPE='); */
-#define TYPE_NAME "TYPE="
-
- size = TYPE_OFFSET+strlen(type);
-
- levp[3] = (char *) malloc(size+1);
- if (levp[3] == NULL) {
- pam_syslog(pamh, LOG_CRIT, "no memory for type");
- if (levp) {
- free(levp[2]);
- free(levp[1]);
- free(levp[0]);
- free(levp);
- }
- return -1;
- }
-
- strncpy(levp[3],TYPE_NAME,TYPE_OFFSET);
- strcpy(levp[3]+TYPE_OFFSET, type);
- levp[3][size] = '\0'; /* <NUL> terminate */
-
- levp[4] = NULL; /* end list */
-
- *evp = levp;
- }
-
- if ((ctrl & FILTER_DEBUG) && *filtername) {
- char **e;
-
- pam_syslog(pamh, LOG_DEBUG, "filter[%s]: %s", type, *filtername);
- pam_syslog(pamh, LOG_DEBUG, "environment:");
- for (e=*evp; e && *e; ++e) {
- pam_syslog(pamh, LOG_DEBUG, " %s", *e);
- }
- }
-
- return ctrl;
-}
-
-static void free_evp(char *evp[])
-{
- int i;
-
- if (evp)
- for (i=0; i<4; ++i) {
- if (evp[i])
- free(evp[i]);
- }
- free(evp);
-}
-
-static int
-set_filter (pam_handle_t *pamh, int flags UNUSED, int ctrl,
- const char **evp, const char *filtername)
-{
- int status=-1;
- char terminal[TERMINAL_LEN];
- struct termios stored_mode; /* initial terminal mode settings */
- int fd[2], child=0, child2=0, aterminal;
-
- if (filtername == NULL || *filtername != '/') {
- pam_syslog(pamh, LOG_ALERT,
- "filtername not permitted; full pathname required");
- return PAM_ABORT;
- }
-
- if (!isatty(STDIN_FILENO) || !isatty(STDOUT_FILENO)) {
- aterminal = 0;
- } else {
- aterminal = 1;
- }
-
- if (aterminal) {
-
- /* open the master pseudo terminal */
-
- fd[0] = master(pamh,terminal);
- if (fd[0] < 0) {
- pam_syslog(pamh, LOG_CRIT, "no master terminal");
- return PAM_AUTH_ERR;
- }
-
- /* set terminal into raw mode.. remember old mode so that we can
- revert to it after the child has quit. */
-
- /* this is termios terminal handling... */
-
- if ( tcgetattr(STDIN_FILENO, &stored_mode) < 0 ) {
- pam_syslog(pamh, LOG_CRIT, "couldn't copy terminal mode: %m");
- /* in trouble, so close down */
- close(fd[0]);
- return PAM_ABORT;
- } else {
- struct termios t_mode = stored_mode;
-
- t_mode.c_iflag = 0; /* no input control */
- t_mode.c_oflag &= ~OPOST; /* no ouput post processing */
-
- /* no signals, canonical input, echoing, upper/lower output */
-#ifdef XCASE
- t_mode.c_lflag &= ~(XCASE);
-#endif
- t_mode.c_lflag &= ~(ISIG|ICANON|ECHO);
- t_mode.c_cflag &= ~(CSIZE|PARENB); /* no parity */
- t_mode.c_cflag |= CS8; /* 8 bit chars */
-
- t_mode.c_cc[VMIN] = 1; /* number of chars to satisfy a read */
- t_mode.c_cc[VTIME] = 0; /* 0/10th second for chars */
-
- if ( tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_mode) < 0 ) {
- pam_syslog(pamh, LOG_WARNING,
- "couldn't put terminal in RAW mode: %m");
- close(fd[0]);
- return PAM_ABORT;
- }
-
- /*
- * NOTE: Unlike the stream socket case here the child
- * opens the slave terminal as fd[1] *after* the fork...
- */
- }
- } else {
-
- /*
- * not a terminal line so just open a stream socket fd[0-1]
- * both set...
- */
-
- if ( socketpair(AF_UNIX, SOCK_STREAM, 0, fd) < 0 ) {
- pam_syslog(pamh, LOG_CRIT, "couldn't open a stream pipe: %m");
- return PAM_ABORT;
- }
- }
-
- /* start child process */
-
- if ( (child = fork()) < 0 ) {
-
- pam_syslog(pamh, LOG_WARNING, "first fork failed: %m");
- if (aterminal) {
- (void) tcsetattr(STDIN_FILENO, TCSAFLUSH, &stored_mode);
- }
-
- return PAM_AUTH_ERR;
- }
-
- if ( child == 0 ) { /* child process *is* application */
-
- if (aterminal) {
-
- /* close the controlling tty */
-
-#if defined(__hpux) && defined(O_NOCTTY)
- int t = open("/dev/tty", O_RDWR|O_NOCTTY);
-#else
- int t = open("/dev/tty",O_RDWR);
- if (t > 0) {
- (void) ioctl(t, TIOCNOTTY, NULL);
- close(t);
- }
-#endif /* defined(__hpux) && defined(O_NOCTTY) */
-
- /* make this process it's own process leader */
- if (setsid() == -1) {
- pam_syslog(pamh, LOG_WARNING,
- "child cannot become new session: %m");
- return PAM_ABORT;
- }
-
- /* find slave's name */
- terminal[5] = 't'; /* want to open slave terminal */
- fd[1] = open(terminal, O_RDWR);
- close(fd[0]); /* process is the child -- uses line fd[1] */
-
- if (fd[1] < 0) {
- pam_syslog(pamh, LOG_WARNING,
- "cannot open slave terminal: %s: %m", terminal);
- return PAM_ABORT;
- }
-
- /* initialize the child's terminal to be the way the
- parent's was before we set it into RAW mode */
-
- if ( tcsetattr(fd[1], TCSANOW, &stored_mode) < 0 ) {
- pam_syslog(pamh, LOG_WARNING,
- "cannot set slave terminal mode: %s: %m", terminal);
- close(fd[1]);
- return PAM_ABORT;
- }
-
- } else {
-
- /* nothing to do for a simple stream socket */
-
- }
-
- /* re-assign the stdin/out to fd[1] <- (talks to filter). */
-
- if ( dup2(fd[1],STDIN_FILENO) != STDIN_FILENO ||
- dup2(fd[1],STDOUT_FILENO) != STDOUT_FILENO ||
- dup2(fd[1],STDERR_FILENO) != STDERR_FILENO ) {
- pam_syslog(pamh, LOG_WARNING,
- "unable to re-assign STDIN/OUT/ERR: %m");
- close(fd[1]);
- return PAM_ABORT;
- }
-
- /* make sure that file descriptors survive 'exec's */
-
- if ( fcntl(STDIN_FILENO, F_SETFD, 0) ||
- fcntl(STDOUT_FILENO,F_SETFD, 0) ||
- fcntl(STDERR_FILENO,F_SETFD, 0) ) {
- pam_syslog(pamh, LOG_WARNING,
- "unable to re-assign STDIN/OUT/ERR: %m");
- return PAM_ABORT;
- }
-
- /* now the user input is read from the parent/filter: forget fd */
-
- close(fd[1]);
-
- /* the current process is now aparently working with filtered
- stdio/stdout/stderr --- success! */
-
- return PAM_SUCCESS;
- }
-
- /*
- * process is the parent here. So we can close the application's
- * input/output
- */
-
- close(fd[1]);
-
- /* Clear out passwords... there is a security problem here in
- * that this process never executes pam_end. Consequently, any
- * other sensitive data in this process is *not* explicitly
- * overwritten, before the process terminates */
-
- (void) pam_set_item(pamh, PAM_AUTHTOK, NULL);
- (void) pam_set_item(pamh, PAM_OLDAUTHTOK, NULL);
-
- /* fork a copy of process to run the actual filter executable */
-
- if ( (child2 = fork()) < 0 ) {
-
- pam_syslog(pamh, LOG_WARNING, "filter fork failed: %m");
- child2 = 0;
-
- } else if ( child2 == 0 ) { /* exec the child filter */
-
- if ( dup2(fd[0],APPIN_FILENO) != APPIN_FILENO ||
- dup2(fd[0],APPOUT_FILENO) != APPOUT_FILENO ||
- dup2(fd[0],APPERR_FILENO) != APPERR_FILENO ) {
- pam_syslog(pamh, LOG_WARNING,
- "unable to re-assign APPIN/OUT/ERR: %m");
- close(fd[0]);
- exit(1);
- }
-
- /* make sure that file descriptors survive 'exec's */
-
- if ( fcntl(APPIN_FILENO, F_SETFD, 0) == -1 ||
- fcntl(APPOUT_FILENO,F_SETFD, 0) == -1 ||
- fcntl(APPERR_FILENO,F_SETFD, 0) == -1 ) {
- pam_syslog(pamh, LOG_WARNING,
- "unable to retain APPIN/OUT/ERR: %m");
- close(APPIN_FILENO);
- close(APPOUT_FILENO);
- close(APPERR_FILENO);
- exit(1);
- }
-
- /* now the user input is read from the parent through filter */
-
- execle(filtername, "<pam_filter>", NULL, evp);
-
- /* getting to here is an error */
-
- pam_syslog(pamh, LOG_ALERT, "filter: %s: %m", filtername);
-
- } else { /* wait for either of the two children to exit */
-
- while (child && child2) { /* loop if there are two children */
- int lstatus=0;
- int chid;
-
- chid = wait(&lstatus);
- if (chid == child) {
-
- if (WIFEXITED(lstatus)) { /* exited ? */
- status = WEXITSTATUS(lstatus);
- } else if (WIFSIGNALED(lstatus)) { /* killed ? */
- status = -1;
- } else
- continue; /* just stopped etc.. */
- child = 0; /* the child has exited */
-
- } else if (chid == child2) {
- /*
- * if the filter has exited. Let the child die
- * naturally below
- */
- if (WIFEXITED(lstatus) || WIFSIGNALED(lstatus))
- child2 = 0;
- } else {
-
- pam_syslog(pamh, LOG_ALERT,
- "programming error <chid=%d,lstatus=%x> "
- "in file %s at line %d",
- chid, lstatus, __FILE__, __LINE__);
- child = child2 = 0;
- status = -1;
-
- }
- }
- }
-
- close(fd[0]);
-
- /* if there is something running, wait for it to exit */
-
- while (child || child2) {
- int lstatus=0;
- int chid;
-
- chid = wait(&lstatus);
-
- if (child && chid == child) {
-
- if (WIFEXITED(lstatus)) { /* exited ? */
- status = WEXITSTATUS(lstatus);
- } else if (WIFSIGNALED(lstatus)) { /* killed ? */
- status = -1;
- } else
- continue; /* just stopped etc.. */
- child = 0; /* the child has exited */
-
- } else if (child2 && chid == child2) {
-
- if (WIFEXITED(lstatus) || WIFSIGNALED(lstatus))
- child2 = 0;
-
- } else {
-
- pam_syslog(pamh, LOG_ALERT,
- "programming error <chid=%d,lstatus=%x> "
- "in file %s at line %d",
- chid, lstatus, __FILE__, __LINE__);
- child = child2 = 0;
- status = -1;
-
- }
- }
-
- if (aterminal) {
- /* reset to initial terminal mode */
- (void) tcsetattr(STDIN_FILENO, TCSANOW, &stored_mode);
- }
-
- if (ctrl & FILTER_DEBUG) {
- pam_syslog(pamh, LOG_DEBUG, "parent process exited"); /* clock off */
- }
-
- /* quit the parent process, returning the child's exit status */
-
- exit(status);
- return status; /* never reached, to make gcc happy */
-}
-
-static int set_the_terminal(pam_handle_t *pamh)
-{
- const void *tty;
-
- if (pam_get_item(pamh, PAM_TTY, &tty) != PAM_SUCCESS
- || tty == NULL) {
- tty = ttyname(STDIN_FILENO);
- if (tty == NULL) {
- pam_syslog(pamh, LOG_ERR, "couldn't get the tty name");
- return PAM_ABORT;
- }
- if (pam_set_item(pamh, PAM_TTY, tty) != PAM_SUCCESS) {
- pam_syslog(pamh, LOG_ERR, "couldn't set tty name");
- return PAM_ABORT;
- }
- }
- return PAM_SUCCESS;
-}
-
-static int need_a_filter(pam_handle_t *pamh
- , int flags, int argc, const char **argv
- , const char *name, int which_run)
-{
- int ctrl;
- char **evp;
- const char *filterfile;
- int retval;
-
- ctrl = process_args(pamh, argc, argv, name, &evp, &filterfile);
- if (ctrl == -1) {
- return PAM_AUTHINFO_UNAVAIL;
- }
-
- /* set the tty to the old or the new one? */
-
- if (!(ctrl & NON_TERM) && !(ctrl & NEW_TERM)) {
- retval = set_the_terminal(pamh);
- if (retval != PAM_SUCCESS) {
- pam_syslog(pamh, LOG_ERR, "tried and failed to set PAM_TTY");
- }
- } else {
- retval = PAM_SUCCESS; /* nothing to do which is always a success */
- }
-
- if (retval == PAM_SUCCESS && (ctrl & which_run)) {
- retval = set_filter(pamh, flags, ctrl
- , (const char **)evp, filterfile);
- }
-
- if (retval == PAM_SUCCESS
- && !(ctrl & NON_TERM) && (ctrl & NEW_TERM)) {
- retval = set_the_terminal(pamh);
- if (retval != PAM_SUCCESS) {
- pam_syslog(pamh, LOG_ERR,
- "tried and failed to set new terminal as PAM_TTY");
- }
- }
-
- free_evp(evp);
-
- if (ctrl & FILTER_DEBUG) {
- pam_syslog(pamh, LOG_DEBUG, "filter/%s, returning %d", name, retval);
- pam_syslog(pamh, LOG_DEBUG, "[%s]", pam_strerror(pamh, retval));
- }
-
- return retval;
-}
-
-/* ----------------- public functions ---------------- */
-
-/*
- * here are the advertised access points ...
- */
-
-/* ------------------ authentication ----------------- */
-
-PAM_EXTERN int pam_sm_authenticate(pam_handle_t *pamh
- , int flags, int argc, const char **argv)
-{
- return need_a_filter(pamh, flags, argc, argv
- , "authenticate", FILTER_RUN1);
-}
-
-PAM_EXTERN int pam_sm_setcred(pam_handle_t *pamh, int flags
- , int argc, const char **argv)
-{
- return need_a_filter(pamh, flags, argc, argv, "setcred", FILTER_RUN2);
-}
-
-/* --------------- account management ---------------- */
-
-PAM_EXTERN int pam_sm_acct_mgmt(pam_handle_t *pamh, int flags, int argc,
- const char **argv)
-{
- return need_a_filter(pamh, flags, argc, argv
- , "setcred", FILTER_RUN1|FILTER_RUN2 );
-}
-
-/* --------------- session management ---------------- */
-
-PAM_EXTERN int pam_sm_open_session(pam_handle_t *pamh, int flags
- , int argc, const char **argv)
-{
- return need_a_filter(pamh, flags, argc, argv
- , "open_session", FILTER_RUN1);
-}
-
-PAM_EXTERN int pam_sm_close_session(pam_handle_t *pamh, int flags
- , int argc, const char **argv)
-{
- return need_a_filter(pamh, flags, argc, argv
- , "close_session", FILTER_RUN2);
-}
-
-/* --------- updating authentication tokens --------- */
-
-
-PAM_EXTERN int pam_sm_chauthtok(pam_handle_t *pamh, int flags
- , int argc, const char **argv)
-{
- int runN;
-
- if (flags & PAM_PRELIM_CHECK)
- runN = FILTER_RUN1;
- else if (flags & PAM_UPDATE_AUTHTOK)
- runN = FILTER_RUN2;
- else {
- pam_syslog(pamh, LOG_ERR, "unknown flags for chauthtok (0x%X)", flags);
- return PAM_TRY_AGAIN;
- }
-
- return need_a_filter(pamh, flags, argc, argv, "chauthtok", runN);
-}
-
-#ifdef PAM_STATIC
-
-/* ------------ stuff for static modules ------------ */
-
-struct pam_module _pam_filter_modstruct = {
- "pam_filter",
- pam_sm_authenticate,
- pam_sm_setcred,
- pam_sm_acct_mgmt,
- pam_sm_open_session,
- pam_sm_close_session,
- pam_sm_chauthtok,
-};
-
-#endif
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