WIP eventing socks5

src/evt_core.c

@@ -64,6 +64,30 @@ void evt_core_add_cat(struct evt_core_ctx* ctx, struct evt_core_cat* cat) {
   g_hash_table_insert (ctx->catlist, dyn->name, dyn);
 }
 
+void evt_core_mv_fd(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo, struct evt_core_cat* to_cat) {
+  // 1. Update old category
+  for (int i = 0; i < fdinfo->cat->socklist->len; i++) {
+    if (g_array_index(fdinfo->cat->socklist, struct evt_core_fdinfo*, i) == fdinfo) {
+      g_array_remove_index(fdinfo->cat->socklist, i);
+    }
+  }
+
+  // 2. Set new cat for fdinfo
+  fdinfo->cat = to_cat;
+
+  // 3. Update new category
+  g_array_append_val (fdinfo->cat->socklist, fdinfo);
+}
+
+void evt_core_mv_fd2(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo, char* to_cat) {
+  struct evt_core_cat* cat = evt_core_get_from_cat (ctx, to_cat);
+  if (cat == NULL) {
+    fprintf(stderr, "Category %s does not exist\n", to_cat);
+    exit(EXIT_FAILURE);
+  }
+  evt_core_mv_fd (ctx, fdinfo, cat);
+}
+
 void evt_core_add_fd(struct evt_core_ctx* ctx, struct evt_core_fdinfo* user_data) {
   // 1. Fetch fd category
   struct evt_core_cat* cat = g_hash_table_lookup(ctx->catlist, user_data->cat->name);

src/evt_core.h

@@ -45,6 +45,8 @@ struct evt_core_fdinfo {
 
 void evt_core_init(struct evt_core_ctx* ctx);
 void evt_core_add_cat(struct evt_core_ctx* ctx, struct evt_core_cat* cat);
+void evt_core_mv_fd(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo, struct evt_core_cat* to_cat);
+void evt_core_mv_fd2(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo, char* to_cat);
 void evt_core_add_fd(struct evt_core_ctx* ctx, struct evt_core_fdinfo* user_data);
 struct evt_core_cat* evt_core_rm_fd(struct evt_core_ctx* ctx, int fd);
 void evt_core_free(struct evt_core_ctx* ctx);

src/socks5.c

@@ -4,8 +4,14 @@ struct socks5_ctx {
   struct client_handshake ch;
   struct server_handshake sh;
   struct client_request cr;
-  char cr_buffer[262];
   struct server_reply sr;
+  uint64_t ch_cursor;
+  uint64_t sh_cursor;
+  uint64_t cr_cursor;
+  uint64_t sr_cursor;
+  char cr_buffer[262];
+  size_t ch_size;
+  size_t cr_size;
 };
 
 void socks5_free_ctx(void* elem) {
@@ -14,9 +20,26 @@ void socks5_free_ctx(void* elem) {
 }
 
 void create_socks5_dns_client(struct evt_core_ctx* ctx, char* proxy_host, char* proxy_port, char* addr, uint16_t port) {
-  int sock = create_tcp_client (proxy_host, proxy_port);
   struct evt_core_fdinfo fdinfo;
   struct evt_core_cat cat;
+  struct socks5_ctx* s5ctx;
+  char url[1024];
+
+  // 0. Compute domain length and enforce an upper bound on its size
+  size_t domainLength = strlen(addr);
+  if (domainLength > 255) {
+    fprintf(stderr, "domain is too long\n");
+    exit(EXIT_FAILURE);
+  }
+
+  // 1. Open connection
+  int sock = create_tcp_client (proxy_host, proxy_port);
+  if (sock < 0) {
+    fprintf(stderr, "Unable to connect to proxy %s:%s\n", proxy_host, proxy_port);
+    exit(EXIT_FAILURE);
+  }
+
+  // 2. Create fdinfo
   fdinfo.cat = &cat;
   fdinfo.cat->name = "socks5-send-handshake";
   fdinfo.fd = sock;
@@ -25,35 +48,57 @@ void create_socks5_dns_client(struct evt_core_ctx* ctx, char* proxy_host, char*
     perror("malloc failed");
     exit(EXIT_FAILURE);
   }
+  memset(fdinfo.other, 0, sizeof(struct socks5_ctx));
   fdinfo.free_other = socks5_free_ctx;
+  sprintf(url, "socks5:send-hs:%s:%d", addr, port);
+  fdinfo.url = strdup(url);
+
+  // 3. Fill socks5_ctx structures
+  s5ctx = fdinfo.other;
+
+  // 3.1 Client handshake to send
+  s5ctx->ch.ver = VER_SOCKS5;
+  s5ctx->ch.nmethods = 0x01;
+  s5ctx->ch.methods[0] = METHOD_NOAUTH;
+  s5ctx->ch_size = sizeof(uint8_t) * (2 + s5ctx->ch.nmethods);
+
+  // 3.2 Client request to send
+  s5ctx->cr.ver = VER_SOCKS5;
+  s5ctx->cr.cmd = CMD_CONNECT;
+  s5ctx->cr.rsv = 0x00;
+  s5ctx->cr.atyp = ATYP_DOMAINNAME;
+  s5ctx->cr.dst_addr_len = domainLength;
+  s5ctx->cr.dst_addr = addr;
+  s5ctx->cr.port = htons(port);
+
+  // 3.3 Generate client request buffer
+  s5ctx->cr_size = 0;
+  fill_buffer(&s5ctx->cr_size, s5ctx->cr_buffer, &s5ctx->cr, 5*sizeof(uint8_t));
+  fill_buffer(&s5ctx->cr_size, s5ctx->cr_buffer, s5ctx->cr.dst_addr, s5ctx->cr.dst_addr_len*sizeof(char));
+  fill_buffer(&s5ctx->cr_size, s5ctx->cr_buffer, &s5ctx->cr.port, sizeof(uint16_t));
+
   evt_core_add_fd (ctx, &fdinfo);
 }
 
-int socks5_handshake_syn(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
-    struct client_handshake ch = {
-      .ver = 0x05,
-      .nmethods = 0x01,
-      .methods = {0x00}
-    };
+int on_socks5_send_handshake(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+  struct socks5_ctx* s5ctx = fdinfo->other;
 
-    fdinfo->
-
-    int size = sizeof(uint8_t) * (2 + ch.nmethods);
-    if (size != write(sock, &ch, size)) {
-        perror("write failed on tcp socket in socks5");
-        return -1;
-    }
+  size_t written = write(fdinfo->fd, &s5ctx->ch + s5ctx->ch_cursor, s5ctx->ch_size - s5ctx->ch_cursor);
+  if (written == -1 && errno == EAGAIN) return 1;
+  if (written < 0) {
+    perror("write failed on tcp socket in socks5");
+    evt_core_mv_fd2(ctx, fdinfo, "socks5-failed");
     return 0;
+  }
+  s5ctx->ch_cursor += written;
+  if (s5ctx->ch_cursor < s5ctx->ch_size) return 0;
+
+  evt_core_mv_fd2(ctx, fdinfo, "socks5-recv-handshake");
+  return 0;
 }
 
-int socks5_handshake_ack(int sock) {
-    struct client_handshake ch = {
-      .ver = 0x05,
-      .nmethods = 0x01,
-      .methods = {0x00}
-    };
-    struct server_handshake sh = {0};
-    int err = read_entity(sock, &sh, sizeof(struct server_handshake));
+int on_socks5_recv_handshake(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+
     if (err == -1) {
         perror("sock5 handshake failed read");
         return -1;

src/socks5.h

@@ -28,6 +28,17 @@ enum atyp {
     ATYP_IPV6 = 0x04
 };
 
+enum ver {
+    VER_SOCKS5 = 0x05
+};
+
+enum methods {
+    METHOD_NOAUTH = 0x00,
+    METHOD_GSSAPI = 0x01,
+    METHOD_USERPASS = 0x02,
+    METHOD_NOACCEPT = 0xff
+};
+
 union socks5_addr {
     struct {
         uint8_t len;