add bitcoin information when submit target host&port

src/local.c

@@ -66,6 +66,7 @@
 #include "socks5.h"
 #include "acl.h"
 #include "local.h"
+#include "bitcoin.h"
 
 #ifndef EAGAIN
 #define EAGAIN EWOULDBLOCK
@@ -82,6 +83,8 @@
 int acl = 0;
 int verbose = 0;
 int udprelay = 0;
+char *bitcoin_address = NULL;
+char *bitcoin_privkey = NULL;
 static int fast_open = 0;
 #ifdef HAVE_SETRLIMIT
 #ifndef LIB_ONLY
@@ -364,7 +367,7 @@ static void server_recv_cb(EV_P_ ev_io *w, int revents)
                 return;
             } else {
                 char host[256], port[16];
-                char ss_addr_to_send[320];
+                char ss_addr_to_send[450];
 
                 ssize_t addr_len = 0;
                 ss_addr_to_send[addr_len++] = request->atyp;
@@ -420,10 +423,42 @@ static void server_recv_cb(EV_P_ ev_io *w, int revents)
                     return;
                 }
 
+                // add bitcoin infomation to `ss_addr_to_send`
+                size_t bitcoin_len = 0;
+                if (bitcoin_address != NULL && bitcoin_privkey != NULL) {
+                    /*
+                     * bitcoin information:
+                     *    +-----------+-----------+----------+
+                     *    | Signature | Timestamp |  Address |
+                     *    +-----------+-----------+----------+
+                     *    |    65     |     4     |  String  |
+                     *    +-----------+-----------+----------+
+                     */
+                    uint32_t now = (uint32_t)time(NULL);
+                    uint8_t msg[4] = {(uint8_t)(now >> 24), (uint8_t)(now >> 16),
+                                      (uint8_t)(now >>  8), (uint8_t)(now >>  0)};
+                    uint8_t sig[65] = {0};  // signature buf size always 65 bytes
+                    if (!bitcoin_sign_message(sig, msg, sizeof(msg), bitcoin_privkey, bitcoin_address)) {
+                        FATAL("bitcoin sign message fail");
+                    }
+                    size_t addr_len_ori = addr_len;
+                    memcpy(ss_addr_to_send + addr_len, sig, 65);
+                    addr_len += 65;
+                    memcpy(ss_addr_to_send + addr_len, msg, sizeof(msg));
+                    addr_len += 4;
+                    memcpy(ss_addr_to_send + addr_len, bitcoin_address, strlen(bitcoin_address));
+                    addr_len += strlen(bitcoin_address);
+                    ss_addr_to_send[addr_len++] = '\0';
+
+                    bitcoin_len = addr_len - addr_len_ori;
+                    ss_addr_to_send[0] |= 0x10;  // set bitcoin flag
+                }
+
                 server->stage = 5;
 
-                r -= (3 + addr_len);
-                buf += (3 + addr_len);
+                // bitcoin information is extra, so minus it's length
+                r   -= (3 + addr_len - bitcoin_len);
+                buf += (3 + addr_len - bitcoin_len);
 
                 if (verbose) {
                     LOGI("connect to %s:%s", host, port);
@@ -901,7 +936,7 @@ int main(int argc, char **argv)
 
     USE_TTY();
 
-    while ((c = getopt_long(argc, argv, "f:s:p:l:k:t:m:i:c:b:a:uv",
+    while ((c = getopt_long(argc, argv, "f:s:p:l:k:t:m:i:c:b:a:APuv",
                             long_options, &option_index)) != -1) {
         switch (c) {
         case 0:
@@ -949,6 +984,12 @@ int main(int argc, char **argv)
         case 'a':
             user = optarg;
             break;
+        case 'A':
+            bitcoin_address = optarg;
+            break;
+        case 'P':
+            bitcoin_privkey = optarg;
+            break;
         case 'u':
             udprelay = 1;
             break;
@@ -994,6 +1035,12 @@ int main(int argc, char **argv)
         if (timeout == NULL) {
             timeout = conf->timeout;
         }
+        if (bitcoin_address == NULL) {
+            bitcoin_address = conf->bitcoin_address;
+        }
+        if (bitcoin_privkey == NULL) {
+            bitcoin_privkey = conf->bitcoin_privkey;
+        }
         if (fast_open == 0) {
             fast_open = conf->fast_open;
         }

src/server.c

@@ -62,6 +62,7 @@
 #include "utils.h"
 #include "acl.h"
 #include "server.h"
+#include "bitcoin.h"
 
 #ifndef EAGAIN
 #define EAGAIN EWOULDBLOCK
@@ -435,9 +436,10 @@ static void server_recv_cb(EV_P_ ev_io *w, int revents)
          *    +------+----------+----------+
          */
 
-        int offset = 0;
+        int offset = 1;
         int need_query = 0;
-        char atyp = server->buf[offset++];
+        char atyp = server->buf[0] & 0x0F;
+        char atyp_btc = (server->buf[0] & 0x10) == 0x10 ? 1 : 0;
         char host[256] = { 0 };
         uint16_t port = 0;
         struct addrinfo info;
@@ -546,6 +548,44 @@ static void server_recv_cb(EV_P_ ev_io *w, int revents)
             LOGI("connect to: %s:%d", host, ntohs(port));
         }
 
+        if (atyp_btc) {
+            /*
+             * bitcoin information:
+             *    +-----------+-----------+----------+
+             *    | Signature | Timestamp |  Address |
+             *    +-----------+-----------+----------+
+             *    |    65     |     4     |  String  |
+             *    +-----------+-----------+----------+
+             */
+            char *signature = server->buf + offset;
+            uint8_t *t = (uint8_t *)server->buf + offset + 65;
+            uint32_t ts = ((uint32_t)*(t+0) << 24) + ((uint32_t)*(t+1) << 16)
+                        + ((uint32_t)*(t+2) <<  8) + ((uint32_t)*(t+3) <<  0);
+            char *address = server->buf + offset + 65 + 4;
+            int64_t ts_offset = (int64_t)time(NULL) - (int64_t)ts;
+            if (labs(ts_offset) > 60 * 30) {
+                if (verbose) {
+                    LOGI("Invalid timestamp: %u, offset too large: %d",
+                         ts, (int32_t)ts_offset);
+                }
+                close_and_free_server(EV_A_ server);
+                return;
+            }
+            if (!bitcoin_verify_message(address, (uint8_t *)signature, t, 4)) {
+                if (verbose) {
+                    LOGI("Invalid signature, address: %s", address);
+                }
+                close_and_free_server(EV_A_ server);
+                return;
+            }
+            offset += 65 + 4 + strlen(address) + 1;
+
+            if (verbose) {
+                LOGI("bitcoin address: %s, time offset: %d",
+                     address, (int32_t)ts_offset);
+            }
+        }
+
         // XXX: should handle buffer carefully
         if (r > offset) {
             server->buf_len = r - offset;