continue work

srcs/main.c

@@ -10,9 +10,9 @@ static char args_doc[] = "HOST ...";
 #define ARG_TTL 256
 
 static struct argp_option options[] = {
-    {0, 0, 0, 0, "Options valid for all request types:\n"},
-    {"verbose", 'v', 0, 0, "verbose output"},
-    {"ttl", ARG_TTL, "N", 0, "specify N as time-to-live"},
+    {0, 0, 0, 0, "Options valid for all request types:\n", 0},
+    {"verbose", 'v', 0, 0, "verbose output", 0},
+    {"ttl", ARG_TTL, "N", 0, "specify N as time-to-live", 0},
     {0},
 };
 
@@ -46,7 +46,42 @@ static bool stop = false;
 
 int sock = 0;
 
-void send_ping() {}
+static struct sockaddr_in destination;
+
+unsigned long xmit = 0;
+unsigned long recvd = 0;
+
+double min = 0;
+double max = 0;
+double avg = 0;
+
+uint16_t calc_checksum(void * b, const size_t l) {
+    uint16_t sum = 0;
+
+    for (int i = 0; i < l; i++) {
+        sum += *((uint16_t*)b + i);
+    }
+
+    return ~sum;
+}
+
+void send_ping() {
+    struct ping_pkt packet = {0};
+
+    packet.hdr.type = ICMP_ECHO;
+    packet.hdr.un.echo.id = getpid();
+    packet.hdr.un.echo.sequence = xmit++;
+
+    for (int i = 0; i < sizeof(packet.msg) - 1; ++i) {
+        packet.msg[i] = (char)i;
+    }
+    packet.msg[sizeof(packet.msg) - 1] = '\0';
+
+    packet.hdr.checksum = calc_checksum(&packet, sizeof(packet));
+
+    sendto(sock, &packet, sizeof(packet), 0, (struct sockaddr*)&destination, sizeof(destination));
+    alarm(1);
+}
 
 void sig_handler(int sig) {
     if (sig == SIGINT) {
@@ -62,6 +97,16 @@ int main(int argc, char** argv) {
     arguments.ttl = 64;
     argp_parse(&argp, argc, argv, 0, 0, &arguments);
 
+    memset(&destination, 0, sizeof(destination));
+
+    destination.sin_family = AF_INET;
+    destination.sin_addr.s_addr = inet_addr(arguments.args[0]);
+    if (destination.sin_addr.s_addr == INADDR_NONE) {
+        dprintf(sock, "%s: unknown host\n", argv[0]);
+        exit(1);
+    }
+    destination.sin_port = htons(IPPORT_ECHO);
+
     sock = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
 
     if (sock < 0) {
@@ -74,7 +119,7 @@ int main(int argc, char** argv) {
         close(sock);
         exit(1);
     }
-    
+
     struct sigaction sig_handle;
 
     sig_handle.sa_handler = sig_handler;
@@ -82,10 +127,7 @@ int main(int argc, char** argv) {
     sigaction(SIGINT, &sig_handle, 0);
     sigaction(SIGALRM, &sig_handle, 0);
 
-    // alarm(1);
-
-    unsigned long xmit = 0;
-    unsigned long recv = 0;
+    alarm(1);
 
     while (true) {
 
@@ -95,7 +137,7 @@ int main(int argc, char** argv) {
     }
     printf("---- %s ping statistics ----\n", arguments.args[0]);
     printf("%zu packets transmitted, %zu packets received, %%zu%% packet loss\n", xmit,
-           recv /*, (xmit - recv) / xmit * 100*/);
+           recvd /*, (xmit - recv) / xmit * 100*/);
     // printf("round-trip min/avg/max/stddev = %f/%f/%f/%f ms\n");
     close(sock);
 }