Replace my "inane" usage of snprintf to copy strings with strncpy as

used by OpenBSD.  (Quite frankly, I think it's perfectly reasonable to
use snprintf to copy strings, given that the semantics for strncpy()
are utterly idiotic and there is no POSIX sstrncpy().)

While I'm at it, incorporate some of OpenBSD's bugfixes to cron.

NOT for 2.2

1 files changed, 20 insertions, 8 deletions

diff --git a/usr.sbin/cron/crontab/crontab.c b/usr.sbin/cron/crontab/crontab.c
index 12e7b93..6b4b9dc 100644
--- a/usr.sbin/cron/crontab/crontab.c
+++ b/usr.sbin/cron/crontab/crontab.c
@@ -17,7 +17,7 @@
  */
 
 #if !defined(lint) && !defined(LINT)
-static char rcsid[] = "$Id: crontab.c,v 1.5 1996/08/05 00:31:27 pst Exp $";
+static char rcsid[] = "$Id: crontab.c,v 1.6 1996/08/05 00:50:02 pst Exp $";
 #endif
 
 /* crontab - install and manage per-user crontab files
@@ -142,7 +142,8 @@ parse_args(argc, argv)
 		fprintf(stderr, "bailing out.\n");
 		exit(ERROR_EXIT);
 	}
-	strcpy(User, pw->pw_name);
+	(void) strncpy(User, pw->pw_name, (sizeof User)-1);
+	User[(sizeof User)-1] = '\0';
 	strcpy(RealUser, User);
 	Filename[0] = '\0';
 	Option = opt_unknown;
@@ -165,7 +166,8 @@ parse_args(argc, argv)
 					ProgramName, optarg);
 				exit(ERROR_EXIT);
 			}
-			(void) snprintf(User, sizeof(user), "%s", optarg);
+			(void) strncpy(User, pw->pw_name, (sizeof User)-1);
+			User[(sizeof User)-1] = '\0';
 			break;
 		case 'l':
 			if (Option != opt_unknown)
@@ -196,8 +198,9 @@ parse_args(argc, argv)
 	} else {
 		if (argv[optind] != NULL) {
 			Option = opt_replace;
-			(void) snprintf(Filename, sizeof(Filename), "%s",
-					argv[optind]);
+			(void) strncpy (Filename, argv[optind], (sizeof Filename)-1);
+			Filename[(sizeof Filename)-1] = '\0';
+
 		} else {
 			usage("file name must be specified for replace");
 		}
@@ -299,6 +302,7 @@ edit_cmd() {
 	time_t		mtime;
 	WAIT_T		waiter;
 	PID_T		pid, xpid;
+	mode_t		um;
 
 	log_it(RealUser, Pid, "BEGIN EDIT", User);
 	(void) sprintf(n, CRON_TAB(User));
@@ -315,11 +319,14 @@ edit_cmd() {
 		}
 	}
 
-	(void) sprintf(Filename, "/tmp/crontab.%d", Pid);
-	if (-1 == (t = open(Filename, O_CREAT|O_EXCL|O_RDWR, 0600))) {
+	um = umask(077);
+	(void) sprintf(Filename, "/tmp/crontab.XXXXXXXXXX");
+	if ((t = mkstemp(Filename)) == -1) {
 		perror(Filename);
+		(void) umask(um);
 		goto fatal;
 	}
+	(void) umask(um);
 #ifdef HAS_FCHOWN
 	if (fchown(t, getuid(), getgid()) < 0) {
 #else
@@ -480,7 +487,7 @@ edit_cmd() {
 		goto done;
 	default:
 		fprintf(stderr, "%s: panic: bad switch() in replace_cmd()\n",
-			ProgramName);
+		    ProgramName);
 		goto fatal;
 	}
  remove:
@@ -503,6 +510,11 @@ replace_cmd() {
 	time_t	now = time(NULL);
 	char	**envp = env_init();
 
+	if (envp == NULL) {
+		fprintf(stderr, "%s: Cannot allocate memory.\n", ProgramName);
+		return (-2);
+	}
+
 	(void) sprintf(n, "tmp.%d", Pid);
 	(void) sprintf(tn, CRON_TAB(n));
 	if (!(tmp = fopen(tn, "w+"))) {