libsystemd-network: Export checksum function to test case

Remove identical checksum function implementation from the test
case code.

3 files changed, 10 insertions, 32 deletions

diff --git a/src/libsystemd-network/dhcp-internal.h b/src/libsystemd-network/dhcp-internal.h
index 3c3e1f649f..064b13b59f 100644
--- a/src/libsystemd-network/dhcp-internal.h
+++ b/src/libsystemd-network/dhcp-internal.h
@@ -48,6 +48,8 @@ int dhcp_option_parse(DHCPMessage *message, size_t len,
 int dhcp_message_init(DHCPMessage *message, uint8_t op, uint32_t xid, uint8_t type,
                       uint8_t **opt, size_t *optlen);
 
+uint16_t dhcp_packet_checksum(void *buf, int len);
+
 void dhcp_packet_append_ip_headers(DHCPPacket *packet, be32_t source_addr,
                                    uint16_t source, be32_t destination_addr,
                                    uint16_t destination, uint16_t len);
diff --git a/src/libsystemd-network/dhcp-packet.c b/src/libsystemd-network/dhcp-packet.c
index 418a9773f2..bed942fd84 100644
--- a/src/libsystemd-network/dhcp-packet.c
+++ b/src/libsystemd-network/dhcp-packet.c
@@ -69,7 +69,7 @@ int dhcp_message_init(DHCPMessage *message, uint8_t op, uint32_t xid,
         return 0;
 }
 
-static uint16_t dhcp_checksum(void *buf, int len) {
+uint16_t dhcp_packet_checksum(void *buf, int len) {
         uint32_t sum;
         uint16_t *check;
         int i;
@@ -109,11 +109,11 @@ void dhcp_packet_append_ip_headers(DHCPPacket *packet, be32_t source_addr,
         packet->udp.len = htobe16(len - DHCP_IP_SIZE);
 
         packet->ip.check = packet->udp.len;
-        packet->udp.check = dhcp_checksum(&packet->ip.ttl, len - 8);
+        packet->udp.check = dhcp_packet_checksum(&packet->ip.ttl, len - 8);
 
         packet->ip.ttl = IPDEFTTL;
         packet->ip.check = 0;
-        packet->ip.check = dhcp_checksum(&packet->ip, DHCP_IP_SIZE);
+        packet->ip.check = dhcp_packet_checksum(&packet->ip, DHCP_IP_SIZE);
 }
 
 int dhcp_packet_verify_headers(DHCPPacket *packet, size_t len, bool checksum) {
@@ -150,7 +150,7 @@ int dhcp_packet_verify_headers(DHCPPacket *packet, size_t len, bool checksum) {
                 return -EINVAL;
         }
 
-        if (dhcp_checksum(&packet->ip, hdrlen)) {
+        if (dhcp_packet_checksum(&packet->ip, hdrlen)) {
                 log_dhcp_client(client, "ignoring packet: invalid IP checksum");
                 return -EINVAL;
         }
@@ -175,7 +175,7 @@ int dhcp_packet_verify_headers(DHCPPacket *packet, size_t len, bool checksum) {
                 packet->ip.check = packet->udp.len;
                 packet->ip.ttl = 0;
 
-                if (dhcp_checksum(&packet->ip.ttl,
+                if (dhcp_packet_checksum(&packet->ip.ttl,
                                   be16toh(packet->udp.len) + 12)) {
                         log_dhcp_client(client, "ignoring packet: invalid UDP checksum");
                         return -EINVAL;
diff --git a/src/libsystemd-network/test-dhcp-client.c b/src/libsystemd-network/test-dhcp-client.c
index 8061e5fa83..cfc75ae0a7 100644
--- a/src/libsystemd-network/test-dhcp-client.c
+++ b/src/libsystemd-network/test-dhcp-client.c
@@ -102,30 +102,6 @@ static void test_request_basic(sd_event *e)
         assert_se(sd_dhcp_client_set_request_option(client, 33) == -EEXIST);
 }
 
-static uint16_t client_checksum(void *buf, int len)
-{
-        uint32_t sum;
-        uint16_t *check;
-        int i;
-        uint8_t *odd;
-
-        sum = 0;
-        check = buf;
-
-        for (i = 0; i < len / 2 ; i++)
-                sum += check[i];
-
-        if (len & 0x01) {
-                odd = buf;
-                sum += odd[len - 1];
-        }
-
-        while (sum >> 16)
-                sum = (sum & 0xffff) + (sum >> 16);
-
-        return ~sum;
-}
-
 static void test_checksum(void)
 {
         uint8_t buf[20] = {
@@ -137,7 +113,7 @@ static void test_checksum(void)
         if (verbose)
                 printf("* %s\n", __FUNCTION__);
 
-        assert_se(client_checksum(&buf, 20) == be16toh(0x78ae));
+        assert_se(dhcp_packet_checksum(&buf, 20) == be16toh(0x78ae));
 }
 
 static int check_options(uint8_t code, uint8_t len, const uint8_t *option,
@@ -173,13 +149,13 @@ int dhcp_network_send_raw_socket(int s, const union sockaddr_union *link,
         discover->ip.ttl = 0;
         discover->ip.check = discover->udp.len;
 
-        udp_check = ~client_checksum(&discover->ip.ttl, len - 8);
+        udp_check = ~dhcp_packet_checksum(&discover->ip.ttl, len - 8);
         assert_se(udp_check == 0xffff);
 
         discover->ip.ttl = IPDEFTTL;
         discover->ip.check = ip_check;
 
-        ip_check = ~client_checksum(&discover->ip, sizeof(discover->ip));
+        ip_check = ~dhcp_packet_checksum(&discover->ip, sizeof(discover->ip));
         assert_se(ip_check == 0xffff);
 
         assert_se(discover->dhcp.xid);