ipv6 + misc

client/main.cpp

@@ -1,5 +1,10 @@
 #include "../common/defines.h"
 #include <arpa/inet.h>
+#include <cerrno>
+#include <cstdlib>
+#include <cstring>
+#include <iostream>
+#include <netdb.h>
 #include <netinet/in.h>
 #include <openssl/err.h>
 #include <openssl/ssl.h>
@@ -54,23 +59,47 @@ int main(int argc, char *argv[]) {
     error("Error setting cipher list");
   }
 
-  // Create a TCP socket
+  // Socket creation will be handled in the connection loop
   int sockfd = socket(AF_INET, SOCK_STREAM, 0);
   if (sockfd < 0)
     error("Socket creation failed");
 
   // Set up server address
-  struct sockaddr_in serv_addr;
+  struct sockaddr_storage serv_addr;
   memset(&serv_addr, 0, sizeof(serv_addr));
-  serv_addr.sin_family = AF_INET;
-  serv_addr.sin_port = htons(atoi(argv[2]));
-  if (inet_pton(AF_INET, argv[1], &serv_addr.sin_addr) <= 0)
-    error("Invalid address/address not supported");
 
-  // Connect to server
-  if (connect(sockfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0)
+  struct addrinfo hints, *res;
+  memset(&hints, 0, sizeof(hints));
+  hints.ai_family = AF_UNSPEC; // Enable IPv4/IPv6 dual support
+  hints.ai_socktype = SOCK_STREAM;
+
+  // Resolve hostname and port together
+  int status = getaddrinfo(argv[1], argv[2], &hints, &res);
+  if (status != 0) {
+    std::cerr << "Resolution failed: " << gai_strerror(status) << "\n";
+    std::exit(EINVAL);
+  }
+
+  // Try all addresses until successful connection
+  struct addrinfo *rp;
+  for (rp = res; rp != NULL; rp = rp->ai_next) {
+    sockfd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
+    if (sockfd == -1)
+      continue;
+
+    if (connect(sockfd, rp->ai_addr, rp->ai_addrlen) == 0)
+      break; // Success
+
+    close(sockfd);
+    sockfd = -1;
+  }
+  freeaddrinfo(res); // Free after connection attempts
+
+  if (sockfd == -1) {
+    std::cerr << "Failed to connect to all resolved addresses\n";
+    freeaddrinfo(res);
     error("Connection failed");
-
+  }
   printf("Connected to %s:%s\n", argv[1], argv[2]);
 
   // Create an SSL object