stddev

Makefile

@@ -2,7 +2,7 @@
 
 # Project Meta Settings
 NAME = ft_ping
-RELEASE_TYPE = Release
+RELEASE_TYPE = Debug
 CURRENT_DIR = ${CURDIR}
 
 # Project Build Output Settings

includes/main.h

@@ -13,6 +13,7 @@
 #include <errno.h>
 #include <string.h>
 #include <netinet/ip_icmp.h>
+#include <netinet/ip.h>
 #include <poll.h>
 #include <time.h>
 #include <sys/time.h>

srcs/main.c

@@ -1,5 +1,21 @@
 #include <main.h>
 
+// ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿
+// ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡟⠉⠀⢻⣿⣿⣿⣿⣿⣿⡿⠁⠀⠙⢿⣿⣿
+// ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⠏⠀⠀⠀⣾⣿⣿⣿⣿⣿⣿⠇⠀⠀⠀⠈⣿⣿
+// ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⠀⠀⠀⠀⠿⠛⠛⠛⠛⠿⣿⠀⠀⠀⠀⢀⣿⣿
+// ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⠀⣀⣤⡀⠀⠀⠀⠀⣀⡀⠀⠀⠀⢀⠀⢸⣿⣿
+// ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡿⣴⣿⣿⠇⠀⠀⢠⣾⣿⣿⣆⠀⠀⠀⠀⣿⣿⣿
+// ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡿⢡⣿⣿⣿⠀⠀⢀⣿⣿⣿⣿⣿⠀⠀⠀⢸⣿⣿⣿
+// ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⠁⢸⣿⡿⠃⠀⠀⢸⣿⣿⣿⣿⠏⠀⠀⠀⡘⣿⣿⣿
+// ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡀⠀⠈⠀⠈⠭⠀⠈⠛⠿⠛⠋⠀⠀⠀⠀⠠⣿⣿⣿
+// ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣷⡑⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢸⣿⣿
+// ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣷⠈⠂⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢸⣿⣿
+// ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡏⠀⢣⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢸⣿⣿
+// ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡿⠀⠀⠈⢃⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣼⣿⣿
+// ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⠁⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣿⣿⣿
+// ⣿⣿⣿⣿⣿⣿⣿⣿⡿⠃⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢸⣿⣿⣿
+
 const char* argp_program_version = "ft_ping 1.0";
 const char* argp_program_bug_address = "<jrathelo@student.42nice.fr>";
 static char doc[] = "Send ICMP ECHO_REQUEST packets to network hosts.\vMandatory or optional arguments to long options "
@@ -54,10 +70,6 @@ struct timespec sendt;
 unsigned long xmit = 0;
 unsigned long recvd = 0;
 
-double min = 0;
-double max = 0;
-double avg = 0;
-
 uint16_t calc_checksum(void* b, size_t len) {
     unsigned short* buf = b;
     unsigned int sum = 0;
@@ -88,7 +100,7 @@ void send_ping() {
     struct timeval tmp_tv;
     gettimeofday(&tmp_tv, NULL);
 
-    memcpy(packet.msg, &tmp_tv, sizeof(tmp_tv));
+    memcpy(packet.msg, &tmp_tv, sizeof(struct timeval));
     for (long unsigned i = 0; i < sizeof(packet.msg) - sizeof(tmp_tv); ++i) {
         packet.msg[sizeof(tmp_tv) + i] = (char)i;
     }
@@ -108,18 +120,36 @@ void sig_handler(int sig) {
     }
 }
 
+double nabs(double a) { return (a < 0) ? -a : a; }
+
+double nsqrt(double a, double prec) {
+    double b;
+    double c;
+
+    if (a < 0) {
+        return 0;
+    }
+    if (a < prec) {
+        return 0;
+    }
+    c = a / 2;
+    do {
+        b = c;
+        c = (b + a / b) / 2;
+    } while (nabs(c - b) > prec);
+
+    return c;
+}
+
 int main(int argc, char** argv) {
     struct arguments arguments;
     int timeout = 3000;
     struct timespec recvt;
     struct pollfd fds[1];
-    float min;
-    float max;
-    float avg;
-
-    min = INT32_MAX;
-    max = 0;
-    avg = 0;
+    double min = INT32_MAX;
+    double max = 0;
+    double avg = 0;
+    double stddev = 0;
 
     arguments.verbose = 0;
     arguments.ttl = 64;
@@ -151,20 +181,22 @@ int main(int argc, char** argv) {
     fds[0].fd = sock;
     fds[0].events = POLLIN;
 
-    struct sigaction sig_handle;
+    struct sigaction sig_handle = {0};
 
     sig_handle.sa_handler = sig_handler;
 
     sigaction(SIGINT, &sig_handle, 0);
     sigaction(SIGALRM, &sig_handle, 0);
 
+    printf("PING %s (%s): %ld data bytes\n", arguments.args[0], arguments.args[0], 64 - sizeof(struct icmphdr));
+
     send_ping();
 
     while (!stop) {
         int ret = poll(fds, 1, timeout);
         if (ret > 0) {
             if (fds[0].revents & POLLIN) {
-                char buf[100];
+                char buf[100] = {0};
 
                 long int bytes_received = recvfrom(sock, buf, 100, 0, NULL, NULL);
 
@@ -173,34 +205,56 @@ int main(int argc, char** argv) {
                     return 1;
                 }
 
+                if ((size_t)bytes_received < sizeof(struct ip) + sizeof(struct icmphdr) + 8) {
+                    dprintf(STDERR_FILENO, "packet too short (%ld bytes) from %s\n", bytes_received, arguments.args[0]);
+                    pause();
+                    continue;
+                }
+
                 clock_gettime(CLOCK_MONOTONIC, &recvt);
 
                 struct ip* ip_header = (struct ip*)buf;
                 struct icmphdr* icmp_reply = (struct icmphdr*)(buf + (ip_header->ip_hl << 2));
 
+                int old_checksum = icmp_reply->checksum;
+                icmp_reply->checksum = 0;
+
+                if (old_checksum != calc_checksum(icmp_reply, bytes_received - (ip_header->ip_hl << 2))) {
+                    dprintf(STDERR_FILENO, "checksum mismatch from %s\n", arguments.args[0]);
+                    pause();
+                    continue;
+                }
+
+                icmp_reply->checksum = old_checksum;
+
                 float tmp =
                     ((recvt.tv_sec * 1000 + recvt.tv_nsec / 1000000) - (sendt.tv_sec * 1000 + sendt.tv_nsec / 1000000));
-                tmp += ((float) ((recvt.tv_nsec - sendt.tv_nsec) % 1000000) / 1000000.0);
+                tmp += ((float)((recvt.tv_nsec - sendt.tv_nsec) % 1000000) / 1000000.0);
 
-                printf("%zd bytes from %s: icmp_seq=%d ttl=%d time=%.3f ms \n", bytes_received, arguments.args[0],
-                       icmp_reply->un.echo.sequence, ip_header->ip_ttl, tmp);
+                printf("%zd bytes from %s: icmp_seq=%d ttl=%d time=%.3f ms \n", bytes_received - sizeof(struct ip),
+                       arguments.args[0], icmp_reply->un.echo.sequence + 1, ip_header->ip_ttl, tmp);
 
                 min = (((min) < (tmp)) ? (min) : (tmp));
                 max = (((max) > (tmp)) ? (max) : (tmp));
                 avg += tmp;
+                stddev += tmp * tmp;
                 recvd++;
             }
         } else if (ret == 0) {
             printf("No reply received within the timeout period\n");
-        } else {
-            perror("Poll failed");
         }
+        // else {
+        // perror("Poll failed");
+        // }
 
         pause();
     }
+    fflush(stdout);
     printf("---- %s ping statistics ----\n", arguments.args[0]);
     printf("%zu packets transmitted, %zu packets received, %zu%% packet loss\n", xmit, recvd,
            (xmit - recvd) / xmit * 100);
-    printf("round-trip min/avg/max/stddev = %.3f/%.3f/%.3f/%%.3f ms\n", min, max, avg / recvd);
+    avg /= recvd;
+    stddev = stddev / recvd - avg * avg;
+    printf("round-trip min/avg/max/stddev = %.3f/%.3f/%.3f/%.3f ms\n", min, max, avg, nsqrt(stddev, 0.0005));
     close(sock);
 }