#11 basic support for multiple users. some work left
This commit is contained in:
Erik Ekman
parent
7994402806
commit
8d766e2857
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@ -43,9 +43,16 @@ struct query {
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};
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struct user {
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int id;
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char id;
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int active;
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time_t last_pkt;
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int seed;
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in_addr_t tun_ip;
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struct sockaddr host;
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int addrlen;
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struct query q;
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struct packet inpacket;
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struct packet outpacket;
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};
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int open_dns(int, in_addr_t);
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36
src/iodine.c
36
src/iodine.c
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@ -54,6 +54,7 @@ uint16_t rand_seed;
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/* Current IP packet */
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static char activepacket[4096];
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static char userid;
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static int lastlen;
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static int packetpos;
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static int packetlen;
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@ -223,10 +224,12 @@ tunnel(int tun_fd, int dns_fd)
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static void
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send_chunk(int fd)
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{
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char hex[] = "0123456789ABCDEF";
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char packet[4096];
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struct query q;
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char buf[4096];
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int avail;
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int code;
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char *p;
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int len;
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@ -238,11 +241,14 @@ send_chunk(int fd)
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avail = packetlen - packetpos;
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lastlen = dns_build_hostname(buf + 1, sizeof(buf) - 1, p, avail, topdomain);
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if (lastlen == avail)
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buf[0] = '1';
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code = 1;
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else
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buf[0] = '0';
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code = 0;
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code |= (userid << 1);
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buf[0] = hex[code];
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len = dns_encode(packet, sizeof(packet), &q, QR_QUERY, buf, strlen(buf));
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sendto(fd, packet, len, 0, (struct sockaddr*)&peer, sizeof(peer));
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@ -251,13 +257,14 @@ send_chunk(int fd)
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void
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send_login(int fd, char *login, int len)
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{
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char data[18];
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char data[19];
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memset(data, 0, sizeof(data));
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memcpy(data, login, MIN(len, 16));
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data[0] = userid;
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memcpy(&data[1], login, MIN(len, 16));
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data[16] = (rand_seed >> 8) & 0xff;
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data[17] = (rand_seed >> 0) & 0xff;
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data[17] = (rand_seed >> 8) & 0xff;
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data[18] = (rand_seed >> 0) & 0xff;
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rand_seed++;
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@ -267,7 +274,7 @@ send_login(int fd, char *login, int len)
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static void
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send_ping(int fd)
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{
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char data[2];
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char data[3];
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if (is_sending()) {
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lastlen = 0;
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@ -275,8 +282,9 @@ send_ping(int fd)
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packetlen = 0;
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}
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data[0] = (rand_seed >> 8) & 0xff;
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data[1] = (rand_seed >> 0) & 0xff;
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data[0] = userid;
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data[1] = (rand_seed >> 8) & 0xff;
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data[2] = (rand_seed >> 0) & 0xff;
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rand_seed++;
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@ -336,7 +344,7 @@ handshake(int dns_fd)
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continue;
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}
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if (read >= 8) {
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if (read >= 9) {
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payload = (((in[4] & 0xff) << 24) |
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((in[5] & 0xff) << 16) |
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((in[6] & 0xff) << 8) |
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@ -344,13 +352,17 @@ handshake(int dns_fd)
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if (strncmp("VACK", in, 4) == 0) {
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seed = payload;
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userid = in[8];
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printf("Version ok, both running 0x%08x\n", VERSION);
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printf("Version ok, both running 0x%08x. You are user #%d\n", VERSION, userid);
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goto perform_login;
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} else {
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} else if (strncmp("VACK", in, 4) == 0) {
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errx(1, "you run 0x%08x, server runs 0x%08x. giving up\n",
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VERSION, payload);
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/* NOTREACHED */
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} else if (strncmp("VFUL", in, 4) == 0) {
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errx(1, "server full, all %d slots are taken. try again later\n", payload);
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/* NOTREACHED */
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}
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} else
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warnx("did not receive proper login challenge\n");
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228
src/iodined.c
228
src/iodined.c
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@ -30,6 +30,7 @@
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#include <pwd.h>
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#include <arpa/inet.h>
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#include <netinet/in.h>
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#include <netinet/ip.h>
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#include <zlib.h>
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#include "common.h"
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@ -41,15 +42,10 @@
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int running = 1;
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struct packet packetbuf;
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struct packet outpacket;
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int outid;
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char *topdomain;
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struct query q;
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struct user u;
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#define USERS 8
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struct user users[USERS];
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char password[33];
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int my_mtu;
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@ -64,34 +60,96 @@ sigint(int sig)
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running = 0;
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}
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static void
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init_users()
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{
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int i;
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char newip[16];
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memset(users, 0, USERS * sizeof(struct user));
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for (i = 0; i < USERS; i++) {
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users[i].id = i;
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snprintf(newip, sizeof(newip), "0.0.0.%d", i + 1);
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users[i].tun_ip = my_ip + inet_addr(newip);;
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users[i].inpacket.len = 0;
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users[i].inpacket.offset = 0;
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users[i].outpacket.len = 0;
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users[i].q.id = 0;
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}
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}
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static int
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find_user_by_ip(uint32_t ip)
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{
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int ret = -1;
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int i;
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for (i = 0; i < USERS; i++) {
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/* Not used at all or not used in one minute */
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if (users[i].active && users[i].last_pkt + 60 > time(NULL) &&
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ip == users[i].tun_ip) {
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ret = i;
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break;
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}
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}
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return ret;
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}
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static int
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find_available_user()
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{
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int ret = -1;
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int i;
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for (i = 0; i < USERS; i++) {
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/* Not used at all or not used in one minute */
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if (!users[i].active || users[i].last_pkt + 60 < time(NULL)) {
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users[i].active = 1;
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users[i].last_pkt = time(NULL);
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ret = i;
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break;
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}
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}
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return ret;
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}
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static int
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tunnel_tun(int tun_fd, int dns_fd)
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{
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unsigned long outlen;
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struct iphdr *header;
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char out[64*1024];
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char in[64*1024];
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int userid;
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int read;
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if ((read = read_tun(tun_fd, in, sizeof(in))) <= 0)
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return 0;
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/* find target ip in packet, in is padded with 4 bytes TUN header */
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header = (struct iphdr*) (in + 4);
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userid = find_user_by_ip(header->daddr);
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if (userid < 0)
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return 0;
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outlen = sizeof(out);
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compress2((uint8_t*)out, &outlen, (uint8_t*)in, read, 9);
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memcpy(outpacket.data, out, outlen);
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outpacket.len = outlen;
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memcpy(users[userid].outpacket.data, out, outlen);
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users[userid].outpacket.len = outlen;
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return outlen;
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}
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typedef enum {
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VERSION_ACK,
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VERSION_NACK
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VERSION_NACK,
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VERSION_FULL
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} version_ack_t;
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static void
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send_version_response(int fd, version_ack_t ack, uint32_t payload)
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send_version_response(int fd, version_ack_t ack, uint32_t payload, struct user *u)
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{
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char out[8];
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char out[9];
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switch (ack) {
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case VERSION_ACK:
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@ -100,31 +158,37 @@ send_version_response(int fd, version_ack_t ack, uint32_t payload)
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case VERSION_NACK:
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strncpy(out, "VNAK", sizeof(out));
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break;
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case VERSION_FULL:
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strncpy(out, "VFUL", sizeof(out));
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break;
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}
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out[4] = ((payload >> 24) & 0xff);
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out[5] = ((payload >> 16) & 0xff);
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out[6] = ((payload >> 8) & 0xff);
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out[7] = ((payload) & 0xff);
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out[8] = u->id;
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write_dns(fd, &q, out, 8);
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write_dns(fd, &u->q, out, sizeof(out));
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}
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static int
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tunnel_dns(int tun_fd, int dns_fd)
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{
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struct in_addr clientip;
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struct in_addr tempip;
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struct query q;
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unsigned long outlen;
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struct in_addr myip;
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char logindata[16];
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char out[64*1024];
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char in[64*1024];
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static int seed;
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char *tmp[2];
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int userid;
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int version;
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int read;
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int code;
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userid = -1;
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if ((read = read_dns(dns_fd, &q, in, sizeof(in))) <= 0)
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return 0;
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@ -139,41 +203,63 @@ tunnel_dns(int tun_fd, int dns_fd)
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((in[4] & 0xff)));
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if (version == VERSION) {
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seed = rand();
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send_version_response(dns_fd, VERSION_ACK, seed);
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userid = find_available_user();
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if (userid >= 0) {
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users[userid].seed = rand();
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memcpy(&(users[userid].host), &(q.from), q.fromlen);
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memcpy(&(users[userid].q), &q, sizeof(struct query));
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users[userid].addrlen = q.fromlen;
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send_version_response(dns_fd, VERSION_ACK, users[userid].seed, &users[userid]);
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} else {
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/* No space for another user */
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send_version_response(dns_fd, VERSION_FULL, USERS, NULL);
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}
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} else {
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send_version_response(dns_fd, VERSION_NACK, VERSION);
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send_version_response(dns_fd, VERSION_NACK, VERSION, NULL);
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}
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} else {
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send_version_response(dns_fd, VERSION_NACK, VERSION);
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send_version_response(dns_fd, VERSION_NACK, VERSION, NULL);
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}
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} else if(in[0] == 'L' || in[0] == 'l') {
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/* Login phase, handle auth */
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login_calculate(logindata, 16, password, seed);
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userid = in[1];
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if (userid < 0 || userid >= USERS) {
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write_dns(dns_fd, &q, "BADIP", 5);
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return 0; /* illegal id */
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}
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users[userid].last_pkt = time(NULL);
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login_calculate(logindata, 16, password, users[userid].seed);
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if (read >= 17 && (memcmp(logindata, in+1, 16) == 0)) {
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/* Login ok, send ip/mtu info */
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myip.s_addr = my_ip;
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clientip.s_addr = my_ip + inet_addr("0.0.0.1");
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tmp[0] = strdup(inet_ntoa(myip));
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tmp[1] = strdup(inet_ntoa(clientip));
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read = snprintf(out, sizeof(out), "%s-%s-%d",
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tmp[0], tmp[1], my_mtu);
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/* Store user ip */
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memcpy(&(u.host), &(q.from), q.fromlen);
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u.addrlen = q.fromlen;
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write_dns(dns_fd, &q, out, read);
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q.id = 0;
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free(tmp[1]);
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free(tmp[0]);
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if (q.fromlen != users[userid].addrlen ||
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memcmp(&(users[userid].host), &(q.from), q.fromlen) != 0) {
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write_dns(dns_fd, &q, "BADIP", 5);
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} else {
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write_dns(dns_fd, &q, "LNAK", 4);
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if (read >= 18 && (memcmp(logindata, in+2, 16) == 0)) {
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/* Login ok, send ip/mtu info */
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tempip.s_addr = my_ip;
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tmp[0] = strdup(inet_ntoa(tempip));
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tempip.s_addr = users[userid].tun_ip;
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tmp[1] = strdup(inet_ntoa(tempip));
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read = snprintf(out, sizeof(out), "%s-%s-%d",
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tmp[0], tmp[1], my_mtu);
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write_dns(dns_fd, &q, out, read);
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q.id = 0;
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free(tmp[1]);
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free(tmp[0]);
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} else {
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write_dns(dns_fd, &q, "LNAK", 4);
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}
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}
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} else if(in[0] == 'P' || in[0] == 'p') {
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/* Ping packet, store userid */
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userid = in[1];
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if (userid < 0 || userid >= USERS) {
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write_dns(dns_fd, &q, "BADIP", 5);
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return 0; /* illegal id */
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}
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} else if((in[0] >= '0' && in[0] <= '9')
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|| (in[0] >= 'a' && in[0] <= 'f')
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@ -185,32 +271,40 @@ tunnel_dns(int tun_fd, int dns_fd)
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if ((in[0] >= 'A' && in[0] <= 'F'))
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code = in[0] - 'A' + 10;
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userid = code >> 1;
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if (userid < 0 || userid >= USERS) {
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write_dns(dns_fd, &q, "BADIP", 5);
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return 0; /* illegal id */
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}
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users[userid].last_pkt = time(NULL);
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/* Check sending ip number */
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if (q.fromlen != u.addrlen ||
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memcmp(&(u.host), &(q.from), q.fromlen) != 0) {
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if (q.fromlen != users[userid].addrlen ||
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memcmp(&(users[userid].host), &(q.from), q.fromlen) != 0) {
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write_dns(dns_fd, &q, "BADIP", 5);
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} else {
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memcpy(packetbuf.data + packetbuf.offset, in + 1, read - 1);
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packetbuf.len += read - 1;
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packetbuf.offset += read - 1;
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memcpy(users[userid].inpacket.data + users[userid].inpacket.offset, in + 1, read - 1);
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users[userid].inpacket.len += read - 1;
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users[userid].inpacket.offset += read - 1;
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if (code & 1) {
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outlen = sizeof(out);
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uncompress((uint8_t*)out, &outlen,
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(uint8_t*)packetbuf.data, packetbuf.len);
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(uint8_t*)users[userid].inpacket.data, users[userid].inpacket.len);
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write_tun(tun_fd, out, outlen);
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packetbuf.len = packetbuf.offset = 0;
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users[userid].inpacket.len = users[userid].inpacket.offset = 0;
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}
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}
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}
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if (q.fromlen == u.addrlen &&
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memcmp(&(u.host), &(q.from), q.fromlen) == 0 &&
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outpacket.len > 0) {
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/* userid must be set for a reply to be sent */
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if (userid >= 0 && userid < USERS && q.fromlen == users[userid].addrlen &&
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memcmp(&(users[userid].host), &(q.from), q.fromlen) == 0 &&
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users[userid].outpacket.len > 0) {
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write_dns(dns_fd, &q, outpacket.data, outpacket.len);
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outpacket.len = 0;
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write_dns(dns_fd, &q, users[userid].outpacket.data, users[userid].outpacket.len);
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users[userid].outpacket.len = 0;
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q.id = 0;
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}
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@ -223,18 +317,19 @@ tunnel(int tun_fd, int dns_fd)
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struct timeval tv;
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fd_set fds;
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int i;
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int j;
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while (running) {
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if (q.id != 0) {
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//if (q.id != 0) {
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tv.tv_sec = 0;
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tv.tv_usec = 5000;
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} else {
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/*} else {
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tv.tv_sec = 1;
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tv.tv_usec = 0;
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}
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}*/
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FD_ZERO(&fds);
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if(outpacket.len == 0)
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//if(outpacket.len == 0) TODO fix this
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FD_SET(tun_fd, &fds);
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FD_SET(dns_fd, &fds);
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|
|
@ -247,10 +342,12 @@ tunnel(int tun_fd, int dns_fd)
|
|||
}
|
||||
|
||||
if (i==0) {
|
||||
if (q.id != 0) {
|
||||
write_dns(dns_fd, &q, outpacket.data, outpacket.len);
|
||||
outpacket.len = 0;
|
||||
q.id = 0;
|
||||
for (j = 0; j < USERS; j++) {
|
||||
if (users[j].q.id != 0) {
|
||||
write_dns(dns_fd, &(users[j].q), users[j].outpacket.data, users[j].outpacket.len);
|
||||
users[j].outpacket.len = 0;
|
||||
users[j].q.id = 0;
|
||||
}
|
||||
}
|
||||
} else {
|
||||
if(FD_ISSET(tun_fd, &fds)) {
|
||||
|
|
@ -370,10 +467,6 @@ main(int argc, char **argv)
|
|||
listen_ip = INADDR_ANY;
|
||||
port = 53;
|
||||
|
||||
packetbuf.len = 0;
|
||||
packetbuf.offset = 0;
|
||||
outpacket.len = 0;
|
||||
q.id = 0;
|
||||
memset(password, 0, 33);
|
||||
srand(time(NULL));
|
||||
|
||||
|
|
@ -466,6 +559,7 @@ main(int argc, char **argv)
|
|||
|
||||
my_ip = inet_addr(argv[0]);
|
||||
my_mtu = mtu;
|
||||
init_users();
|
||||
|
||||
printf("Listening to dns for domain %s\n", argv[1]);
|
||||
|
||||
|
|
|
|||
|
|
@ -19,7 +19,7 @@
|
|||
|
||||
// This is the version of the network protocol
|
||||
// It is usually equal to the latest iodine version number
|
||||
#define VERSION 0x00000305
|
||||
#define VERSION 0x00000400
|
||||
|
||||
#endif /* _VERSION_H_ */
|
||||
|
||||
|
|
|
|||
Loading…
Reference in New Issue