ipv6

src/main.cpp

@@ -45,24 +45,29 @@ uint16_t csum(uint16_t *packet, int packlen) {
 }
 
 class Secret {
-    private:
-        char* key;
-        size_t length;
-    public:
-        Secret(char* key): key(key), length(strlen(key)) {}
-        void encrypt(unsigned char* data, size_t length) {
-            for (size_t i = 0; i < length; i++) {
-                data[i] ^= key[i % this->length];
-            }
-        }
-        void decrypt(unsigned char* data, size_t length) {
-            encrypt(data, length);
+private:
+    char *key;
+    size_t length;
+public:
+    Secret(char *key) : key(key), length(strlen(key)) {}
+
+    void encrypt(unsigned char *data, size_t length) {
+        for (size_t i = 0; i < length; i++) {
+            data[i] ^= key[i % this->length];
         }
+    }
+
+    void decrypt(unsigned char *data, size_t length) {
+        encrypt(data, length);
+    }
 };
 
 Secret *localSecret;
 Secret *remoteSecret;
 
+#include <linux/ipv6.h>
+
+
 // internet -> tun
 void inbound(int raw, int tun) {
     unsigned char buffer[ETH_DATA_LEN];
@@ -75,11 +80,20 @@ void inbound(int raw, int tun) {
         auto payload = buffer + overhead;
         auto meta = (Meta *) payload;
         if (!(meta->src_id == remote_id && meta->dst_id == local_id && meta->reversed == 0)) continue;
-        auto inner = (iphdr *) (payload + sizeof(Meta));
+        auto inner = (payload + sizeof(Meta));
         auto payload_length = packet_length - overhead - sizeof(Meta);
-        remoteSecret->decrypt((unsigned char *) inner, payload_length);
+        remoteSecret->decrypt(inner, payload_length);
+        switch (((ipv6hdr *) inner)->version) {
+            case 4:
+                if (csum((uint16_t *) inner, ((iphdr *) inner)->ihl * 4)) continue;
+                break;
+            case 6:
+                // ipv6 don't have checksum, do nothing
+                break;
+            default:
+                continue;
+        }
 //        if (ip_fast_csum(inner, inner->ihl)) continue;
-        if (csum((uint16_t *) inner, inner->ihl * 4)) continue;
 //        std::cout << "packet_length " << packet_length
 //                  << " tot_len " << ntohs(packet->tot_len)
 //                  << " inner->tot_len " << ntohs(inner->tot_len)
@@ -116,7 +130,7 @@ void outbound(int raw, int tun) {
     perror("outbound read");
 }
 
-auto get_var(const char* varname, bool required = false) {
+auto get_var(const char *varname, bool required = false) {
     auto value = getenv(varname);
     if (value == nullptr && required) {
         std::cerr << "missing required environment variable: " << varname << std::endl;
@@ -125,7 +139,7 @@ auto get_var(const char* varname, bool required = false) {
     return value;
 }
 
-auto get_var_number(const char* varname, bool required = false) {
+auto get_var_number(const char *varname, bool required = false) {
     auto value = get_var(varname, required);
     if (value == nullptr) return 0;
     return atoi(value);