float ip

CMakeLists.txt

@@ -5,11 +5,11 @@ set(CMAKE_CXX_STANDARD 23)
 
 add_executable(tun main.cpp)
 
-target_link_libraries(tun -static)
+target_link_libraries(tun)
 
 find_package(Threads REQUIRED)
 target_link_libraries(tun Threads::Threads)
 
-set(Boost_USE_STATIC_LIBS ON)
-find_package(Boost COMPONENTS program_options REQUIRED)
-target_link_libraries(tun Boost::program_options)
+#set(Boost_USE_STATIC_LIBS ON)
+#find_package(Boost COMPONENTS program_options REQUIRED)
+#target_link_libraries(tun Boost::program_options)

Dockerfile

@@ -3,10 +3,11 @@ RUN apk --no-cache add build-base cmake linux-headers boost-dev boost-static
 
 WORKDIR /usr/src/app
 COPY . .
-RUN cmake -DCMAKE_BUILD_TYPE=Release .
+RUN cmake -DCMAKE_BUILD_TYPE=Debug .
 RUN make
 
 FROM alpine
+RUN apk --no-cache add libgcc libstdc++
 COPY --from=builder /usr/src/app/tun .
 
 ENTRYPOINT ["./tun"]

main.cpp

@@ -60,7 +60,7 @@ void encrypt_package(unsigned char *buffer, size_t length) {
 void inbound(int raw, int tun) {
     unsigned char buffer[ETH_DATA_LEN];
     sockaddr_in address{.sin_family = AF_INET};
-    socklen_t address_length;
+    socklen_t address_length = sizeof(address);
     size_t packet_length;
     while ((packet_length = recvfrom(raw, buffer, sizeof(buffer), 0, (sockaddr *) &address, &address_length)) >= 0) {
         auto *packet = (iphdr *) buffer;
@@ -77,6 +77,9 @@ void inbound(int raw, int tun) {
 //                  << " tot_len " << ntohs(packet->tot_len)
 //                  << " inner->tot_len " << ntohs(inner->tot_len)
 //                  << " from " << inet_ntoa(address.sin_addr) << std::endl;
+        if (remote_addr.sin_addr.s_addr != address.sin_addr.s_addr) {
+            std::cout << "float ip: " << inet_ntoa(address.sin_addr) << std::endl;
+        }
         remote_addr = address;
 
         if (write(tun, inner, payload_length) < 0) {
@@ -95,7 +98,8 @@ void outbound(int raw, int tun) {
     meta->reversed = 0;
     auto inner = buffer + sizeof(Meta);
     size_t packet_length;
-    while ((packet_length = read(tun, inner, sizeof(buffer) - sizeof(Meta))) >= 0) {
+    while ((packet_length = read(tun, inner, sizeof(buffer) + sizeof(Meta))) >= 0) {
+//        std::cout << "sendto: " << inet_ntoa(remote_addr.sin_addr) << std::endl;
         if (!remote_addr.sin_addr.s_addr) continue;
         encrypt_package(inner, packet_length);
         if (sendto(raw, buffer, packet_length + sizeof(Meta), 0, (sockaddr *) &remote_addr, sizeof(remote_addr)) < 0) {
@@ -116,7 +120,15 @@ int main(int argc, char *argv[]) {
     auto up = getenv("up");
 
     if (endpoint != nullptr) {
-        remote_addr.sin_addr.s_addr = ((in_addr *) gethostbyname(endpoint)->h_name)->s_addr;
+        auto he = gethostbyname(endpoint);
+        if (he == nullptr) {
+            perror("gethostbyname");
+            return -1;
+        }
+        if (he->h_addr_list[0] == nullptr) {
+            perror("gethostbyname 2");
+        }
+        remote_addr.sin_addr.s_addr = *(in_addr_t *) he->h_addr_list[0];
     }
 
     secret_length = strlen(secret);
@@ -135,6 +147,7 @@ int main(int argc, char *argv[]) {
         perror("tun init error");
         return -1;
     }
+    std::cout << dev << std::endl;
 
     if (ioctl(tun, TUNSETIFF, &ifr) < 0) {
         perror("ioctl error");