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-rw-r--r--modules/pam_unix/lckpwdf.-c117
1 files changed, 0 insertions, 117 deletions
diff --git a/modules/pam_unix/lckpwdf.-c b/modules/pam_unix/lckpwdf.-c
deleted file mode 100644
index b5ff4585..00000000
--- a/modules/pam_unix/lckpwdf.-c
+++ /dev/null
@@ -1,117 +0,0 @@
-/*
- * This is a hack, but until libc and glibc both include this function
- * by default (libc only includes it if nys is not being used, at the
- * moment, and glibc doesn't appear to have it at all) we need to have
- * it here, too. :-(
- *
- * This should not become an official part of PAM.
- *
- * BEGIN_HACK
- */
-
-/*
- * lckpwdf.c -- prevent simultaneous updates of password files
- *
- * Before modifying any of the password files, call lckpwdf(). It may block
- * for up to 15 seconds trying to get the lock. Return value is 0 on success
- * or -1 on failure. When you are done, call ulckpwdf() to release the lock.
- * The lock is also released automatically when the process exits. Only one
- * process at a time may hold the lock.
- *
- * These functions are supposed to be conformant with AT&T SVID Issue 3.
- *
- * Written by Marek Michalkiewicz <marekm@i17linuxb.ists.pwr.wroc.pl>,
- * public domain.
- */
-
-#include <fcntl.h>
-#include <signal.h>
-
-#define LOCKFILE "/etc/.pwd.lock"
-#define TIMEOUT 15
-
-static int lockfd = -1;
-
-static int set_close_on_exec(int fd)
-{
- int flags = fcntl(fd, F_GETFD, 0);
- if (flags == -1)
- return -1;
- flags |= FD_CLOEXEC;
- return fcntl(fd, F_SETFD, flags);
-}
-
-static int do_lock(int fd)
-{
- struct flock fl;
-
- memset(&fl, 0, sizeof fl);
- fl.l_type = F_WRLCK;
- fl.l_whence = SEEK_SET;
- return fcntl(fd, F_SETLKW, &fl);
-}
-
-static void alarm_catch(int sig)
-{
-/* does nothing, but fcntl F_SETLKW will fail with EINTR */
-}
-
-static int lckpwdf(void)
-{
- struct sigaction act, oldact;
- sigset_t set, oldset;
-
- if (lockfd != -1)
- return -1;
-
- lockfd = open(LOCKFILE, O_CREAT | O_WRONLY, 0600);
- if (lockfd == -1)
- return -1;
- if (set_close_on_exec(lockfd) == -1)
- goto cleanup_fd;
-
- memset(&act, 0, sizeof act);
- act.sa_handler = alarm_catch;
- act.sa_flags = 0;
- sigfillset(&act.sa_mask);
- if (sigaction(SIGALRM, &act, &oldact) == -1)
- goto cleanup_fd;
-
- sigemptyset(&set);
- sigaddset(&set, SIGALRM);
- if (sigprocmask(SIG_UNBLOCK, &set, &oldset) == -1)
- goto cleanup_sig;
-
- alarm(TIMEOUT);
- if (do_lock(lockfd) == -1)
- goto cleanup_alarm;
- alarm(0);
- sigprocmask(SIG_SETMASK, &oldset, NULL);
- sigaction(SIGALRM, &oldact, NULL);
- return 0;
-
- cleanup_alarm:
- alarm(0);
- sigprocmask(SIG_SETMASK, &oldset, NULL);
- cleanup_sig:
- sigaction(SIGALRM, &oldact, NULL);
- cleanup_fd:
- close(lockfd);
- lockfd = -1;
- return -1;
-}
-
-static int ulckpwdf(void)
-{
- unlink(LOCKFILE);
- if (lockfd == -1)
- return -1;
-
- if (close(lockfd) == -1) {
- lockfd = -1;
- return -1;
- }
- lockfd = -1;
- return 0;
-}
-/* END_HACK */