[src/trunk]: src/libexec/utmp_update log to both syslog and stderr.

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/a1a3cc359fd8
branches:  trunk
changeset: 769653:a1a3cc359fd8
user:      christos <christos%NetBSD.org@localhost>
date:      Sat Sep 17 01:50:54 2011 +0000

description:
log to both syslog and stderr.

diffstat:

 libexec/utmp_update/Makefile      |   4 +-
 libexec/utmp_update/utmp_update.c |  76 ++++++++++++++++++++++++++------------
 2 files changed, 55 insertions(+), 25 deletions(-)

diffs (170 lines):

diff -r 257f8e073b0b -r a1a3cc359fd8 libexec/utmp_update/Makefile
--- a/libexec/utmp_update/Makefile      Sat Sep 17 01:50:08 2011 +0000
+++ b/libexec/utmp_update/Makefile      Sat Sep 17 01:50:54 2011 +0000
@@ -1,8 +1,10 @@
-#      $NetBSD: Makefile,v 1.3 2002/12/16 22:45:15 wiz Exp $
+#      $NetBSD: Makefile,v 1.4 2011/09/17 01:50:54 christos Exp $
 
 PROG=  utmp_update
 MAN=   utmp_update.8
 BINOWN=        root
 BINMODE=4555
 
+COPTS.utmp_update.c += -Wno-format-nonliteral
+
 .include <bsd.prog.mk>
diff -r 257f8e073b0b -r a1a3cc359fd8 libexec/utmp_update/utmp_update.c
--- a/libexec/utmp_update/utmp_update.c Sat Sep 17 01:50:08 2011 +0000
+++ b/libexec/utmp_update/utmp_update.c Sat Sep 17 01:50:54 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: utmp_update.c,v 1.9 2009/04/13 03:38:15 christos Exp $  */
+/*     $NetBSD: utmp_update.c,v 1.10 2011/09/17 01:50:54 christos Exp $         */
 
 /*-
  * Copyright (c) 2002 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 #include <sys/cdefs.h>
 
-__RCSID("$NetBSD: utmp_update.c,v 1.9 2009/04/13 03:38:15 christos Exp $");
+__RCSID("$NetBSD: utmp_update.c,v 1.10 2011/09/17 01:50:54 christos Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -46,8 +46,28 @@
 #include <string.h>
 #include <unistd.h>
 #include <paths.h>
+#include <stdarg.h>
+#include <errno.h>
+#include <syslog.h>
 
-int main(int, char *[]);
+static __dead void
+logerr(int e, const char *fmt, ...)
+{
+       va_list sap, eap;
+       char *s = NULL;
+       
+       if (e)
+               (void)asprintf(&s, "%s (%s)", fmt, strerror(e));
+       if (s)
+               fmt = s;
+
+       va_start(sap, fmt);
+       va_copy(eap, sap);
+       vsyslog(LOG_ERR, fmt, sap);
+       va_end(sap);
+       errx(1, fmt, eap);
+       va_end(eap);
+}
 
 int
 main(int argc, char *argv[])
@@ -63,42 +83,45 @@
 
        euid = geteuid();
        ruid = getuid();
-       if (seteuid(ruid) == -1)
-               err(1, "seteuid");
 
        if (argc != 2) {
                (void)fprintf(stderr, "Usage: %s <vis-utmpx-entry>\n",
-                       getprogname());
-               exit(1);
+                   getprogname());
+               return 1;
        }
 
+       openlog(getprogname(), LOG_PID | LOG_NDELAY, LOG_AUTH);
+       if (seteuid(ruid) == -1)
+               logerr(errno, "Can't setuid %ld", (long)ruid);
+
        len = strlen(argv[1]);
 
        if (len > sizeof(*utx) * 4 + 1 || len < sizeof(*utx))
-               errx(1, "Bad argument");
+               logerr(0, "Bad argument size %zu", len);
 
        if ((utx = malloc(len)) == NULL)
-               err(1, NULL);
+               logerr(errno, "Can't allocate %zu", len);
 
        res = strunvis((char *)utx, argv[1]);
        if (res != (int)sizeof(*utx))
-               errx(1, "Decoding error %s %d != %zu", argv[1], res, sizeof(*utx));
+               logerr(0, "Decoding error %s %d != %zu", argv[1], res,
+                   sizeof(*utx));
 
        switch (utx->ut_type) {
        case USER_PROCESS:
        case DEAD_PROCESS:
                break;
        default:
-               errx(1, "Invalid utmpx type %d", (int)utx->ut_type);
+               logerr(0, "Invalid utmpx type %d", (int)utx->ut_type);
        }
 
        if (ruid != 0) {
                if ((pwd = getpwuid(ruid)) == NULL)
-                       errx(1, "User %lu does not exist in password database",
-                           (long)ruid);
+                       logerr(0, "User %ld does not exist in password"
+                           " database", (long)ruid);
 
                if (strcmp(pwd->pw_name, utx->ut_name) != 0)
-                       errx(1, "Current user `%s' does not match "
+                       logerr(0, "Current user `%s' does not match "
                            "`%s' in utmpx entry", pwd->pw_name, utx->ut_name);
        }
 
@@ -106,34 +129,39 @@
        fd = open(tty, O_RDONLY|O_NONBLOCK, 0);
        if (fd != -1) {
                if (fstat(fd, &st) == -1)
-                       err(1, "Cannot stat `%s'", tty);
+                       logerr(errno, "Cannot stat `%s'", tty);
                if (ruid != 0 && st.st_uid != ruid)
-                       errx(1, "%s: Is not owned by you", tty);
+                       logerr(0, "%s: Is not owned by you", tty);
                if (!isatty(fd))
-                       errx(1, "%s: Not a tty device", tty);
+                       logerr(0, "%s: Not a tty device", tty);
                (void)close(fd);
                if (access(tty, W_OK|R_OK) == -1)
-                       err(1, "%s", tty);
+                       logerr(errno, "Can't access `%s'", tty);
        } else {
                struct utmpx utold, *utoldp;
+               pid_t ppid;
+
                /*
                 * A daemon like ftpd that does not use a tty line? 
                 * We only allow it to kill its own existing entries 
                 */
                if (utx->ut_type != DEAD_PROCESS)
-                       err(1, "Cannot open `%s'", tty);
+                       logerr(errno, "Cannot open `%s'", tty);
 
                (void)memcpy(utold.ut_line, utx->ut_line, sizeof(utx->ut_line));
                if ((utoldp = getutxline(&utold)) == NULL)
-                       err(1, "Cannot find existing entry for `%s'",
+                       logerr(0, "Cannot find existing entry for `%s'",
                            utx->ut_line);
-               if (utoldp->ut_pid != getppid())
-                       err(1, "Cannot modify entry for `%s'", tty);
+               if (utoldp->ut_pid != (ppid = getppid()))
+                       logerr(0, "Cannot modify entry for `%s' "
+                           "utmp pid %ld != parent %ld", tty,
+                           (long)utoldp->ut_pid, (long)ppid);
        }
 
-       (void)seteuid(euid);
+       if (seteuid(euid) == 1)
+               logerr(errno, "Can't setuid %ld", (long)euid);
        if (pututxline(utx) == NULL)
-               err(1, "Cannot update utmp entry");
+               logerr(errno, "Cannot update utmp entry");
 
        return 0;
 }