From d08424384b643e6de7ef82e8d7550259e48dcc4a Mon Sep 17 00:00:00 2001
From: Andrey Volk <andywolk@gmail.com>
Date: Thu, 5 Oct 2023 18:03:32 +0300
Subject: [PATCH] [Core] Coverity: 1024552 Logically dead code

---
 src/switch_utils.c       | 23 ++++++++-------
 tests/unit/switch_core.c | 60 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 71 insertions(+), 12 deletions(-)

diff --git a/src/switch_utils.c b/src/switch_utils.c
index df7a507920..faffc1cc04 100644
--- a/src/switch_utils.c
+++ b/src/switch_utils.c
@@ -747,7 +747,7 @@ SWITCH_DECLARE(int) switch_parse_cidr(const char *string, ip_t *ip, ip_t *mask,
 	ip_t *maskv = mask;
 	ip_t *ipv = ip;
 
-	switch_copy_string(host, string, sizeof(host)-1);
+	switch_copy_string(host, string, sizeof(host) - 1);
 	bit_str = strchr(host, '/');
 
 	if (!bit_str) {
@@ -758,22 +758,20 @@ SWITCH_DECLARE(int) switch_parse_cidr(const char *string, ip_t *ip, ip_t *mask,
 	bits = atoi(bit_str);
 	ipv6 = strchr(string, ':');
 	if (ipv6) {
-		int i,n;
+		int32_t i, n;
+		uint32_t k;
+
 		if (bits < 0 || bits > 128) {
 			return -2;
 		}
+
 		bits = atoi(bit_str);
 		switch_inet_pton(AF_INET6, host, (unsigned char *)ip);
-		for (n=bits,i=0 ;i < 16; i++){
-			if (n >= 8) {
-				maskv->v6.s6_addr[i] = 0xFF;
-				n -= 8;
-			} else if (n < 8) {
-				maskv->v6.s6_addr[i] = 0xFF & ~(0xFF >> n);
-				n -= n;
-			} else if (n == 0) {
-				maskv->v6.s6_addr[i] = 0x00;
-			}
+
+		for (n = bits, i = 0; i < 16; i++) {
+			k = (n > 8) ? 8 : n;
+			maskv->v6.s6_addr[i] = 0xFF & ~(0xFF >> k);	/* k = 0 gives 0x00, k = 8 gives 0xFF */
+			n -= k;
 		}
 	} else {
 		if (bits < 0 || bits > 32) {
@@ -786,6 +784,7 @@ SWITCH_DECLARE(int) switch_parse_cidr(const char *string, ip_t *ip, ip_t *mask,
 
 		maskv->v4 = 0xFFFFFFFF & ~(0xFFFFFFFF >> bits);
 	}
+
 	*bitp = bits;
 
 	return 0;
diff --git a/tests/unit/switch_core.c b/tests/unit/switch_core.c
index da93fbdef4..1159017571 100644
--- a/tests/unit/switch_core.c
+++ b/tests/unit/switch_core.c
@@ -53,6 +53,66 @@ FST_CORE_BEGIN("./conf")
 		}
 		FST_TEARDOWN_END()
 
+		FST_TEST_BEGIN(test_switch_parse_cidr_v6)
+		{
+			ip_t ip, mask;
+			uint32_t bits;
+
+			fst_check(!switch_parse_cidr("fe80::/10", &ip, &mask, &bits));
+			fst_check_int_equals(bits, 10);
+			fst_check_int_equals(ip.v6.s6_addr[0], 0xfe);
+			fst_check_int_equals(ip.v6.s6_addr[1], 0x80);
+			fst_check_int_equals(ip.v6.s6_addr[2], 0);
+			fst_check_int_equals(mask.v6.s6_addr[0], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[1], 0xc0);
+			fst_check_int_equals(mask.v6.s6_addr[2], 0);
+
+			fst_check(!switch_parse_cidr("::/0", &ip, &mask, &bits));
+			fst_check_int_equals(bits, 0);
+			fst_check_int_equals(ip.v6.s6_addr[0], 0);
+			fst_check_int_equals(ip.v6.s6_addr[1], 0);
+			fst_check_int_equals(ip.v6.s6_addr[2], 0);
+			fst_check_int_equals(mask.v6.s6_addr[0], 0);
+			fst_check_int_equals(mask.v6.s6_addr[1], 0);
+			fst_check_int_equals(mask.v6.s6_addr[2], 0);
+
+			fst_check(!switch_parse_cidr("::1/128", &ip, &mask, &bits));
+			fst_check_int_equals(bits, 128);
+			fst_check_int_equals(ip.v6.s6_addr[0], 0);
+			fst_check_int_equals(ip.v6.s6_addr[1], 0);
+			fst_check_int_equals(ip.v6.s6_addr[2], 0);
+			fst_check_int_equals(ip.v6.s6_addr[3], 0);
+			fst_check_int_equals(ip.v6.s6_addr[4], 0);
+			fst_check_int_equals(ip.v6.s6_addr[5], 0);
+			fst_check_int_equals(ip.v6.s6_addr[6], 0);
+			fst_check_int_equals(ip.v6.s6_addr[7], 0);
+			fst_check_int_equals(ip.v6.s6_addr[8], 0);
+			fst_check_int_equals(ip.v6.s6_addr[9], 0);
+			fst_check_int_equals(ip.v6.s6_addr[10], 0);
+			fst_check_int_equals(ip.v6.s6_addr[11], 0);
+			fst_check_int_equals(ip.v6.s6_addr[12], 0);
+			fst_check_int_equals(ip.v6.s6_addr[13], 0);
+			fst_check_int_equals(ip.v6.s6_addr[14], 0);
+			fst_check_int_equals(ip.v6.s6_addr[15], 1);
+			fst_check_int_equals(mask.v6.s6_addr[0], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[1], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[2], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[3], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[4], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[5], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[6], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[7], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[8], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[9], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[10], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[11], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[12], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[13], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[14], 0xff);
+			fst_check_int_equals(mask.v6.s6_addr[15], 0xff);
+		}
+		FST_TEST_END()
+
 #if ENABLE_SNPRINTFV_TESTS
 		FST_TEST_BEGIN(test_snprintfv_1)
 		{