From: Evan Hunt <each@isc.org>
Date: Tue, 10 Mar 2020 01:52:33 +0000 (-0700)
Subject: replace unsafe ctime() and gmtime() function calls
X-Git-Tag: v9.11.18~21^2~2
X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=c16c095b32d57a484abd2a0918ef36f65c64cbbc;p=thirdparty%2Fbind9.git

replace unsafe ctime() and gmtime() function calls

This silences LGTM warnings that these functions are not thread-safe.

(cherry picked from commit 5703f704273955f6c54627b6e05d8eb009b81337)
---

diff --git a/bin/dnssec/dnssec-settime.c b/bin/dnssec/dnssec-settime.c
index 7afcaee0965..62ef8422c74 100644
--- a/bin/dnssec/dnssec-settime.c
+++ b/bin/dnssec/dnssec-settime.c
@@ -28,6 +28,7 @@
 #include <isc/mem.h>
 #include <isc/print.h>
 #include <isc/string.h>
+#include <isc/time.h>
 #include <isc/util.h>
 
 #include <dns/keyvalues.h>
@@ -109,7 +110,6 @@ printtime(dst_key_t *key, int type, const char *tag, bool epoch,
 	  FILE *stream)
 {
 	isc_result_t result;
-	const char *output = NULL;
 	isc_stdtime_t when;
 
 	if (tag != NULL)
@@ -121,9 +121,19 @@ printtime(dst_key_t *key, int type, const char *tag, bool epoch,
 	} else if (epoch) {
 		fprintf(stream, "%d\n", (int) when);
 	} else {
-		time_t timet = when;
-		output = ctime(&timet);
-		fprintf(stream, "%s", output);
+		time_t now = (time_t)when;
+#ifdef _MSC_VER
+		struct tm *tm = localtime(&now); /* Thread specific. */
+#else
+		struct tm t, *tm = localtime_r(&now, &t);
+#endif
+		unsigned int flen;
+		char timebuf[80];
+
+		flen = strftime(timebuf, sizeof(timebuf),
+				"%a %b %e %H:%M:%S %Y", tm);
+		INSIST(flen > 0U && flen < sizeof(timebuf));
+		fprintf(stream, "%s\n", timebuf);
 	}
 }
 
diff --git a/bin/dnssec/dnssec-signzone.c b/bin/dnssec/dnssec-signzone.c
index 319a8050bd4..8d93be83fa3 100644
--- a/bin/dnssec/dnssec-signzone.c
+++ b/bin/dnssec/dnssec-signzone.c
@@ -2954,13 +2954,21 @@ writeset(const char *prefix, dns_rdatatype_t type) {
 
 static void
 print_time(FILE *fp) {
-	time_t currenttime;
+	time_t currenttime = time(NULL);
+#ifdef _MSC_VER
+	struct tm *tm = localtime(&currenttime); /* Thread specific. */
+#else
+	struct tm t, *tm = localtime_r(&currenttime, &t);
+#endif
+	unsigned int flen;
+	char timebuf[80];
 
 	if (outputformat != dns_masterformat_text)
 		return;
 
-	currenttime = time(NULL);
-	fprintf(fp, "; File written on %s", ctime(&currenttime));
+	flen = strftime(timebuf, sizeof(timebuf), "%a %b %e %H:%M:%S %Y", tm);
+	INSIST(flen > 0U && flen < sizeof(timebuf));
+	fprintf(fp, "; File written on %s\n", timebuf);
 }
 
 static void
diff --git a/lib/dns/gen.c b/lib/dns/gen.c
index 5fbdc3bfd3f..589cd205265 100644
--- a/lib/dns/gen.c
+++ b/lib/dns/gen.c
@@ -689,7 +689,12 @@ main(int argc, char **argv) {
 	}
 
 	if (now != -1) {
-		struct tm *tm = gmtime(&now);
+#ifdef _MSC_VER
+		struct tm *tm = gmtime(&now); /* Thread specific. */
+#else
+		struct tm t, *tm = gmtime_r(&now, &t);
+#endif
+
 		if (tm != NULL && tm->tm_year > 104) {
 			n = snprintf(year, sizeof(year), "-%d",
 				     tm->tm_year + 1900);