diff --git a/src/algo_naive.c b/src/algo_naive.c
index 2ae0af9..744aa35 100644
--- a/src/algo_naive.c
+++ b/src/algo_naive.c
@@ -19,6 +19,7 @@ int on_tcp_co(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
   in_len = sizeof(addr);
   conn_sock1 = accept(fdinfo->fd, (struct sockaddr*)&addr, &in_len);
 
+  if (conn_sock1 == -1 && errno == EAGAIN) return 1;
   if (conn_sock1 == -1) goto co_error;
   conn_sock2 = dup(conn_sock1);
   if (conn_sock2 == -1) goto co_error;
@@ -36,7 +37,7 @@ int on_tcp_co(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
   sprintf(to_fdinfo.url, "tcp:write:127.0.0.1:%s", port);
   evt_core_add_fd (ctx, &to_fdinfo);
 
-  return 1;
+  return 0;
 
 co_error:
   perror("Failed to handle new connection");
diff --git a/src/algo_rr.c b/src/algo_rr.c
index 65fc13f..3872012 100644
--- a/src/algo_rr.c
+++ b/src/algo_rr.c
@@ -47,6 +47,7 @@ int rr_on_tcp_co(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
   in_len = sizeof(addr);
   conn_sock1 = accept(fdinfo->fd, (struct sockaddr*)&addr, &in_len);
 
+  if (conn_sock1 == -1 && errno == EAGAIN) return 1;
   if (conn_sock1 == -1) goto co_error;
   conn_sock2 = dup(conn_sock1);
   if (conn_sock2 == -1) goto co_error;
@@ -64,7 +65,7 @@ int rr_on_tcp_co(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
   sprintf(to_fdinfo.url, "tcp:write:127.0.0.1:%s", port);
   evt_core_add_fd (ctx, &to_fdinfo);
 
-  return 1;
+  return 0;
 
 co_error:
   perror("Failed to handle new connection");
diff --git a/src/donar_client.c b/src/donar_client.c
index bc93276..3fd089c 100644
--- a/src/donar_client.c
+++ b/src/donar_client.c
@@ -5,121 +5,68 @@ void load_onion_services(struct donar_client_ctx* ctx, char* onion_file, int por
   tor_os_read (&(ctx->tos));
 }
 
-void init_tcp_client(struct donar_client_ctx* ctx, int i) {
-  struct evt_core_cat cat = {0};
-  struct evt_core_fdinfo fdinfo = {0};
-  char url_buf[255];
-  int err;
-
-  ctx->ports[i] = 7500 + i;
-  cat.name = "configure-socks5";
-  fdinfo.cat = &cat;
-  fdinfo.url = url_buf;
-
-  while (1) {
-    fdinfo.fd = create_tcp_client("127.0.0.1", "9050");
-    if (fdinfo.fd < 0) goto failed_socks5;
-    ctx->client_sock[i].fd = fdinfo.fd;
-    ctx->client_sock[i].state = SOCKS5_STATE_NEW;
-    sprintf(url_buf, "socks5:dist:%d", i);
-    evt_core_add_fd (&(ctx->evts), &fdinfo);
-    //@FIXME: We suppose that we will be able to do the whole write at once which is wrong
-    err = socks5_handshake_syn(fdinfo.fd);
-    if (err) goto failed_socks5;
-
-    break;
-failed_socks5:
-    fprintf(stderr, "Failed connection for socket %d/%d. Sleeping 2 seconds...\n",i+1, CLIENT_PORT_SIZE);
-    close(fdinfo.fd);
-    sleep(2);
-  }
-}
-
-int configure_tcp_clients(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
-    int err, pos;
-    struct donar_client_ctx* app_ctx = (struct donar_client_ctx*) fdinfo->cat->app_ctx;
-
-    pos = -1;
-    for (int i = 0; i < CLIENT_PORT_SIZE; i++) {
-      if (app_ctx->client_sock[i].fd == fdinfo->fd) {
-        pos = i;
-      }
-    }
-
-    char target_host[255];
+void init_socks5_client(struct donar_client_ctx* app_ctx, int pos) {
+  char target_host[255];
     if (strlen(app_ctx->tos.keys[pos].pub) > 254) {
       fprintf(stderr, "Domain name is too long\n");
       exit(EXIT_FAILURE);
     }
     sprintf(target_host, "%s.onion", app_ctx->tos.keys[pos].pub);
 
-    switch (app_ctx->client_sock[pos].state) {
-    case SOCKS5_STATE_NEW:
-      //@FIXME: We suppose that we will be able to do the whole read at once which is wrong
-      err = socks5_handshake_ack (fdinfo->fd);
-      if (err < 0) goto on_socks5_err;
-      //@FIXME: We suppose that we will be able to do the whole write at once which is wrong too
-      err = socks5_connect_dns(fdinfo->fd, target_host, app_ctx->ports[pos]);
-      if (err < 0) goto on_socks5_err;
-      app_ctx->client_sock[pos].state = SOCKS5_STATE_ACK;
-      printf("Socket %d/%d %s:%d is connecting...\n", pos+1, CLIENT_PORT_SIZE, target_host, app_ctx->ports[pos]);
-      break;
-    case SOCKS5_STATE_ACK:
-      //@FIXME: We suppose that we will be able to do the whole read at once which is wrong too
-      err = socks5_reply (fdinfo->fd);
-      if (err == -SOCKS5_REP_GENERAL_FAILURE || err == -SOCKS5_REP_TTLEXP || err == -SOCKS5_REP_HOSTUNREACH) {
-        fprintf(stderr, "%s is not ready, received %s\n", fdinfo->url, socks5_rep(-err));
-        goto on_socks5_err;
-      } else if (err < 0) {
-        fprintf(stderr, "An other error occured on %s\n", fdinfo->url);
-        exit(EXIT_FAILURE);
-      }
-      app_ctx->client_sock[pos].state = SOCKS5_STATE_RDY;
-      int sock1, sock2;
-      sock1 = dup(fdinfo->fd);
-      sock2 = dup(fdinfo->fd);
-      if (sock1 < 0 || sock2 < 0) {
-        exit(EXIT_FAILURE);
-      }
-      void* fdcat = evt_core_rm_fd (ctx, fdinfo->fd);
-      if (fdcat == NULL) {
-        exit(EXIT_FAILURE);
-      }
 
-      struct evt_core_fdinfo fdinfo = {0};
-      struct evt_core_cat cat = {0};
-      char url[1024];
-      fdinfo.cat = &cat;
-      fdinfo.url = url;
+  app_ctx->ports[pos] = 7500 + pos;
+  socks5_create_dns_client (&app_ctx->evts, "127.0.0.1", "9050", target_host, app_ctx->ports[pos]);
+}
 
-      fdinfo.cat->name = "tcp-write";
-      fdinfo.fd = sock1;
-      sprintf(fdinfo.url, "tcp:write:127.0.0.1:%d", app_ctx->ports[pos]);
-      evt_core_add_fd (ctx, &fdinfo);
+int on_socks5_success(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+  struct evt_core_fdinfo fdinfo_n = {0};
+  struct evt_core_cat cat_n = {0};
+  char url[1024];
+  struct socks5_ctx* s5ctx = fdinfo->other;
+  fdinfo_n.cat = &cat_n;
+  fdinfo_n.url = url;
 
-      fdinfo.cat->name = "tcp-read";
-      fdinfo.fd = sock2;
-      sprintf(fdinfo.url, "tcp:read:127.0.0.1:%d", app_ctx->ports[pos]);
-      evt_core_add_fd (ctx, &fdinfo);
+  fdinfo_n.fd = dup(fdinfo->fd);
+  fdinfo_n.cat->name = "tcp-write";
+  sprintf(fdinfo_n.url, "tcp:write:127.0.0.1:%d", s5ctx->port);
+  evt_core_add_fd (ctx, &fdinfo_n);
 
-      printf("Socket %d/%d %s:%d has been added to the pool!\n", pos+1, CLIENT_PORT_SIZE, target_host, app_ctx->ports[pos]);
-      break;
-    case SOCKS5_STATE_RDY:
-      goto on_socks5_err;
-      break;
-    case SOCKS5_STATE_ERR:
-      goto on_socks5_err;
-      break;
-    }
+  fdinfo_n.fd = dup(fdinfo->fd);
+  fdinfo_n.cat->name = "tcp-read";
+  sprintf(fdinfo_n.url, "tcp:read:127.0.0.1:%d", s5ctx->port);
+  evt_core_add_fd (ctx, &fdinfo_n);
 
-    return 1;
-on_socks5_err:
-    //perror("An error occured while connecting to an Onion Service");
-    app_ctx->client_sock[pos].state = SOCKS5_STATE_ERR;
-    evt_core_rm_fd (ctx, fdinfo->fd);
-    sleep(2);
-    init_tcp_client (app_ctx, pos);
-    return 1;
+  evt_core_rm_fd (ctx, fdinfo->fd);
+  return 1;
+
+failed:
+  fprintf(stderr, "Memory allocation failed\n");
+  exit(EXIT_FAILURE);
+}
+
+int on_socks5_failed(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+  struct donar_client_ctx* app_ctx = fdinfo->cat->app_ctx;
+  struct socks5_ctx* s5ctx = fdinfo->other;
+  int pos = 7500 - s5ctx->port;
+
+  evt_core_rm_fd (ctx, fdinfo->fd);
+  init_socks5_client (app_ctx, pos);
+  return 1;
+}
+
+void init_socks5_sinks(struct donar_client_ctx* app_ctx) {
+  struct evt_core_cat template = { 0 };
+
+  template.cb = on_socks5_success;
+  template.name = "socks5-success";
+  template.flags = EPOLLET;
+  evt_core_add_cat(&app_ctx->evts, &template);
+
+  template.cb = on_socks5_failed;
+  template.app_ctx = app_ctx;
+  template.name = "socks5-failed";
+  template.flags = EPOLLET;
+  evt_core_add_cat(&app_ctx->evts, &template);
 }
 
 void donar_client(struct donar_client_ctx* ctx, char* algoname,
@@ -128,16 +75,8 @@ void donar_client(struct donar_client_ctx* ctx, char* algoname,
 
   evt_core_init (&(ctx->evts));
   init_algo(&ctx->evts, &algo, algoname);
-  struct evt_core_cat init_socks5 = {
-    .app_ctx = ctx,
-    .free_app_ctx = NULL,
-    .cb = configure_tcp_clients,
-    .err_cb = NULL,
-    .name = "configure-socks5",
-    .flags = EPOLLIN | EPOLLET,
-    .socklist = NULL
-  };
-  evt_core_add_cat (&(ctx->evts), &init_socks5);
+  socks5_init (&ctx->evts);
+  init_socks5_sinks(ctx);
   evt_core_add_cat (&(ctx->evts), &(algo.on_tcp_co));
   evt_core_add_cat (&(ctx->evts), &(algo.on_udp_read));
   evt_core_add_cat (&(ctx->evts), &(algo.on_tcp_read));
@@ -149,7 +88,7 @@ void donar_client(struct donar_client_ctx* ctx, char* algoname,
   printf("--- Onion services loaded\n");
 
   for (int i = 0; i < CLIENT_PORT_SIZE; i++) {
-    init_tcp_client(ctx, i);
+    init_socks5_client(ctx, i);
   }
   printf("--- TCP Clients Connected\n");
 
diff --git a/src/evt_core.c b/src/evt_core.c
index ffe547a..1e7b728 100644
--- a/src/evt_core.c
+++ b/src/evt_core.c
@@ -64,7 +64,39 @@ 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_add_fd(struct evt_core_ctx* ctx, struct evt_core_fdinfo* user_data) {
+void evt_core_mv_fd(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo, struct evt_core_cat* to_cat) {
+  printf("Moving fd=%d from cat=%s to cat=%s\n",fdinfo->fd, fdinfo->cat->name, to_cat->name);
+
+  // 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);
+
+  // 4. Update epoll flags
+  update_fd_epoll (ctx->epollfd, fdinfo->fd, fdinfo->cat->flags);
+
+  // 5. Handle cases where data arrived before registering the file descriptor
+  fdinfo->cat->cb(ctx, 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);
+}
+
+struct evt_core_fdinfo* 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);
   if (cat == NULL) {
@@ -99,6 +131,11 @@ void evt_core_add_fd(struct evt_core_ctx* ctx, struct evt_core_fdinfo* user_data
   // 5. Add file descriptor to epoll
   add_fd_to_epoll(ctx->epollfd, user_data->fd, cat->flags);
   printf("Added fd=%d with url=%s in cat=%s\n", fdinfo->fd, fdinfo->url, fdinfo->cat->name);
+
+  // 6. Ensure that events arrived before epoll registering are handled
+  fdinfo->cat->cb(ctx, fdinfo);
+
+  return fdinfo;
 }
 
 struct evt_core_cat* evt_core_rm_fd(struct evt_core_ctx* ctx, int fd) {
@@ -108,14 +145,11 @@ struct evt_core_cat* evt_core_rm_fd(struct evt_core_ctx* ctx, int fd) {
   struct evt_core_fdinfo* fdinfo = g_hash_table_lookup (ctx->socklist, &fd);
   if (fdinfo == NULL) return NULL;
   cat = fdinfo->cat;
+  printf("Closing fd=%d from cat=%s\n",fdinfo->fd, fdinfo->cat->name);
 
   // 2. Update category
   for (int i = 0; i < cat->socklist->len; i++) {
     if (g_array_index(cat->socklist, struct evt_core_fdinfo*, i) == fdinfo) {
-      if (fdinfo->fd != fd) {
-        fprintf(stderr, "Logic error in updating file descriptor list\n");
-        exit(EXIT_FAILURE);
-      }
       g_array_remove_index(cat->socklist, i);
     }
   }
diff --git a/src/evt_core.h b/src/evt_core.h
index 2f6d96a..0b5b2ac 100644
--- a/src/evt_core.h
+++ b/src/evt_core.h
@@ -45,7 +45,9 @@ 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_add_fd(struct evt_core_ctx* ctx, struct evt_core_fdinfo* user_data);
+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);
+struct evt_core_fdinfo* 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);
 void evt_core_loop(struct evt_core_ctx* ctx);
diff --git a/src/meas_lat.c b/src/meas_lat.c
index e65064f..ebf39be 100644
--- a/src/meas_lat.c
+++ b/src/meas_lat.c
@@ -8,6 +8,11 @@
 #include "net_tools.h"
 #include "socks5.h"
 
+struct measlat_ctx {
+  int count, size, interval;
+  char *host, *port, *transport;
+};
+
 struct measure_conf {
   uint64_t max_measure;
   uint64_t payload_size;
@@ -79,12 +84,19 @@ int on_udp(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
   return 0;
 }
 
+void free_timer_conf(void* v) {
+  struct measure_conf* mc = v;
+  free(mc->payload);
+  free(mc);
+}
+
 int on_timer(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
   ssize_t s;
   uint64_t ticks;
   struct measure_conf* mc = fdinfo->other;
 
   s = read(fdinfo->fd, &ticks, sizeof(uint64_t));
+  if (s == -1 && errno == EAGAIN) return 0;
   if (s != sizeof(uint64_t)) {
     perror("Read error");
     exit(EXIT_FAILURE);
@@ -113,112 +125,9 @@ int on_timer(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
     perror("Send error");
     //exit(EXIT_FAILURE);
   }
-  return 1;
+  return 0;
 }
 
-void free_timer_conf(void* v) {
-  struct measure_conf* mc = v;
-  free(mc->payload);
-  free(mc);
-}
-
-void register_categories(struct evt_core_ctx* evts) {
-    struct evt_core_cat tcp_read = {
-    .app_ctx = NULL,
-    .free_app_ctx = NULL,
-    .cb = on_udp,
-    .err_cb = on_udp_err,
-    .name = "tcp-read",
-    .flags = EPOLLIN | EPOLLET,
-    .socklist = NULL
-  };
-  struct evt_core_cat udp_read = {
-    .app_ctx = NULL,
-    .free_app_ctx = NULL,
-    .cb = on_udp,
-    .err_cb = on_udp_err,
-    .name = "udp-read",
-    .flags = EPOLLIN | EPOLLET,
-    .socklist = NULL
-  };
-  struct evt_core_cat timer = {
-    .app_ctx = NULL,
-    .free_app_ctx = NULL,
-    .cb = on_timer,
-    .err_cb = NULL,
-    .name = "timer",
-    .flags = EPOLLIN | EPOLLET,
-    .socklist = NULL
-  };
-
-  evt_core_init(evts);
-  evt_core_add_cat (evts, &udp_read);
-  evt_core_add_cat (evts, &tcp_read);
-  evt_core_add_cat(evts, &timer);
-  printf("--- Categories registered\n");
-
-}
-
-int register_tor_socket(struct evt_core_ctx* evts, char* host, char* port, int count, int size) {
-  int socks5_sock = -1, err = 0;
-  for (int i = 120; i > 0; i--) {
-    sleep(2);
-    printf("Remaining try %d/120 to connect to %s:%s\n", i, host, port);
-    if (socks5_sock >= 0) {
-      close(socks5_sock);
-      socks5_sock = -1;
-    }
-    socks5_sock = create_tcp_client ("127.0.0.1", "9050");
-    err = socks5_handshake_syn (socks5_sock);
-    if (err < 0) continue;
-    err = socks5_handshake_ack (socks5_sock);
-    if (err < 0) continue;
-    err = socks5_connect_dns (socks5_sock, host, atoi(port));
-    if (err < 0) continue;
-    err = socks5_reply (socks5_sock);
-    if (err < 0) {
-      fprintf(stderr, "Socks5 error %s\n", socks5_rep(-err));
-      continue;
-    }
-    else break;
-  }
-  if (socks5_sock < 0 || err < 0) {
-    exit(EXIT_FAILURE);
-  }
-
-  char url[1024];
-  struct evt_core_cat cat = {0};
-  struct evt_core_fdinfo fdinfo = {0};
-  fdinfo.cat = &cat;
-  fdinfo.url = url;
-
-  fdinfo.fd = socks5_sock;
-  fdinfo.cat->name = "tcp-read";
-  fdinfo.other = create_measure_conf (count, size);
-  fdinfo.free_other = free_mesure_conf;
-  sprintf(fdinfo.url, "tcp:read:%s:%s", host, port);
-  evt_core_add_fd (evts, &fdinfo);
-  printf("--- Tor socket registered\n");
-  return fdinfo.fd;
-}
-
-int register_udp_socket(struct evt_core_ctx* evts, char* host, char* port, int count, int size) {
-  int udp_sock = create_udp_client (host, port);
-  char url[1024];
-  struct evt_core_cat cat = {0};
-  struct evt_core_fdinfo fdinfo = {0};
-  fdinfo.cat = &cat;
-  fdinfo.url = url;
-
-  fdinfo.fd = udp_sock;
-  fdinfo.cat->name = "udp-read";
-  fdinfo.other = create_measure_conf (count, size);
-  fdinfo.free_other = free_mesure_conf;
-  sprintf(fdinfo.url, "udp:read:%s:%s", host, port);
-  evt_core_add_fd (evts, &fdinfo);
-  printf("--- UDP socket registered\n");
-  return fdinfo.fd;
-}
 
 void register_timer(struct evt_core_ctx* evts, int udp, int interval, int count, int size) {
   struct timespec now;
@@ -256,34 +165,144 @@ void register_timer(struct evt_core_ctx* evts, int udp, int interval, int count,
   printf("--- Timer registered\n");
 }
 
+int on_socks5_success_measlat(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+  char url[1024];
+  struct evt_core_cat cat = {0};
+  struct evt_core_fdinfo fdinfo_n = {0};
+  struct socks5_ctx* s5ctx = fdinfo->other;
+  fdinfo_n.cat = &cat;
+  fdinfo_n.url = url;
+
+  struct evt_core_cat* ucat = evt_core_get_from_cat (ctx, "tcp-read");
+  if (ucat == NULL) {
+    fprintf(stderr, "Category udp-read not found\n");
+    exit(EXIT_FAILURE);
+  }
+  struct measlat_ctx* mctx = ucat->app_ctx;
+
+  fdinfo_n.fd = dup(fdinfo->fd);
+  fdinfo_n.cat->name = "tcp-read";
+  fdinfo_n.other = create_measure_conf (mctx->count, mctx->size);
+  fdinfo_n.free_other = free_mesure_conf;
+  sprintf(fdinfo_n.url, "tcp:read:%s:%d", s5ctx->addr, s5ctx->port);
+
+  evt_core_add_fd (ctx, &fdinfo_n);
+  printf("--- Tor socket registered\n");
+
+  register_timer(ctx, fdinfo->fd, mctx->interval, mctx->count, mctx->size);
+  return 1;
+}
+
+void spawn_tor_socket(struct evt_core_ctx* evts) {
+  struct evt_core_cat* ucat = evt_core_get_from_cat (evts, "tcp-read");
+  if (ucat == NULL) {
+    fprintf(stderr, "Category udp-read not found\n");
+    exit(EXIT_FAILURE);
+  }
+  struct measlat_ctx* mctx = ucat->app_ctx;
+
+  socks5_create_dns_client (evts, "127.0.0.1", "9050", mctx->host, atoi(mctx->port));
+}
+
+int on_socks5_failed_measlat(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+  evt_core_rm_fd (ctx, fdinfo->fd);
+  sleep(1);
+  spawn_tor_socket(ctx);
+
+  return 1;
+}
+
+void register_categories(struct evt_core_ctx* evts, struct measlat_ctx* mctx) {
+  struct evt_core_cat template = {0};
+  template.app_ctx = mctx;
+  evt_core_init(evts);
+
+  template.cb = on_timer;
+  template.name = "timer";
+  template.flags = EPOLLIN | EPOLLET;
+  evt_core_add_cat(evts, &template);
+
+  template.cb = on_udp; // intended but not elegant
+  template.err_cb = on_udp_err; // intended but not elegant
+  template.name = "tcp-read";
+  template.flags = EPOLLIN | EPOLLET;
+  evt_core_add_cat(evts, &template);
+
+  template.cb = on_udp;
+  template.err_cb = on_udp_err;
+  template.name = "udp-read";
+  template.flags = EPOLLIN | EPOLLET;
+  evt_core_add_cat(evts, &template);
+
+  template.cb = on_socks5_success_measlat;
+  template.err_cb = on_socks5_failed_measlat;
+  template.name = "socks5-success";
+  template.flags = EPOLLET;
+
+  template.cb = on_socks5_failed_measlat;
+  template.err_cb = on_socks5_failed_measlat;
+  template.name = "socks5-failed";
+  template.flags = EPOLLET;
+
+  socks5_init(evts);
+  printf("--- Categories registered\n");
+
+}
+
+void spawn_udp_socket(struct evt_core_ctx* evts) {
+  struct evt_core_cat* ucat = evt_core_get_from_cat (evts, "udp-read");
+  if (ucat == NULL) {
+    fprintf(stderr, "Category udp-read not found\n");
+    exit(EXIT_FAILURE);
+  }
+  struct measlat_ctx* mctx = ucat->app_ctx;
+
+  int udp_sock = create_udp_client (mctx->host, mctx->port);
+  char url[1024];
+  struct evt_core_cat cat = {0};
+  struct evt_core_fdinfo fdinfo = {0};
+  fdinfo.cat = &cat;
+  fdinfo.url = url;
+
+  fdinfo.fd = udp_sock;
+  fdinfo.cat->name = "udp-read";
+  fdinfo.other = create_measure_conf (mctx->count, mctx->size);
+  fdinfo.free_other = free_mesure_conf;
+  sprintf(fdinfo.url, "udp:read:%s:%s", mctx->host, mctx->port);
+  evt_core_add_fd (evts, &fdinfo);
+  printf("--- UDP socket registered\n");
+
+  register_timer(evts, fdinfo.fd, mctx->interval, mctx->count, mctx->size);
+}
+
 int main(int argc, char** argv) {
   setvbuf(stdout, NULL, _IONBF, 0);
   printf("~ measlat ~\n");
 
-  int opt, udp_fd, count = 0, size = 0, interval = 0;
-  char *host = NULL, *port = NULL, *transport = NULL;
+  int opt;
+  struct measlat_ctx mctx = {0};
   struct evt_core_ctx evts = {0};
 
   // 1. Parse parameters
   while ((opt = getopt(argc, argv, "h:p:c:s:i:t:")) != -1) {
       switch(opt) {
       case 'h': // host
-        host = optarg;
+        mctx.host = optarg;
         break;
       case 'p': // port
-        port = optarg;
+        mctx.port = optarg;
         break;
       case 't': // transport
-        transport = optarg;
+        mctx.transport = optarg;
         break;
       case 'c': // count
-        count = atoi(optarg);
+        mctx.count = atoi(optarg);
         break;
       case 's': // size - payload in bytes
-        size = atoi(optarg);
+        mctx.size = atoi(optarg);
         break;
       case 'i': // interval - every ms
-        interval = atoi(optarg);
+        mctx.interval = atoi(optarg);
         break;
       default:
         goto usage;
@@ -292,17 +311,16 @@ int main(int argc, char** argv) {
 
   // 2. Check and fix parameters
   size_t header_size = sizeof(struct packet_header);
-  if (interval <= 0) interval = 1000;
-  if (count <= 0) count = 1;
-  if (size < header_size) size = header_size;
-  if (transport == NULL) transport = "udp";
-  if (host == NULL || port == NULL) goto usage;
+  if (mctx.interval <= 0) mctx.interval = 1000;
+  if (mctx.count <= 0) mctx.count = 1;
+  if (mctx.size < header_size) mctx.size = header_size;
+  if (mctx.transport == NULL) mctx.transport = "udp";
+  if (mctx.host == NULL || mctx.port == NULL) goto usage;
 
   // 3. Bind events
-  register_categories(&evts);
-  if (strcmp(transport, "udp") == 0) udp_fd = register_udp_socket(&evts, host, port, count, size);
-  else if (strcmp(transport, "tor") == 0) udp_fd = register_tor_socket(&evts, host, port, count, size);
-  register_timer(&evts, udp_fd, interval, count, size);
+  register_categories(&evts, &mctx);
+  if (strcmp(mctx.transport, "udp") == 0) spawn_udp_socket(&evts);
+  else if (strcmp(mctx.transport, "tor") == 0) spawn_tor_socket(&evts);
 
   // 4. Run main loop
   evt_core_loop(&evts);
diff --git a/src/net_tools.c b/src/net_tools.c
index dbee61d..cf1c419 100644
--- a/src/net_tools.c
+++ b/src/net_tools.c
@@ -165,3 +165,13 @@ void add_fd_to_epoll(int epollfd, int fd, uint32_t flags) {
     exit(EXIT_FAILURE);
   }
 }
+
+void update_fd_epoll(int epollfd, int fd, uint32_t flags) {
+  struct epoll_event current_event = {0};
+  current_event.events = flags;
+  current_event.data.fd = fd;
+  if (epoll_ctl (epollfd, EPOLL_CTL_MOD, fd, &current_event) == -1) {
+    perror("Failed to update a file descriptor to epoll with epoll_ctl");
+    exit(EXIT_FAILURE);
+  }
+}
diff --git a/src/net_tools.h b/src/net_tools.h
index 9756c12..a847b9a 100644
--- a/src/net_tools.h
+++ b/src/net_tools.h
@@ -14,5 +14,6 @@ int create_tcp_server(char* host, char* service);
 int create_udp_server(char* host, char* service);
 int make_socket_non_blocking(int fd);
 void add_fd_to_epoll(int epollfd, int fd, uint32_t flags);
+void update_fd_epoll(int epollfd, int fd, uint32_t flags);
 int read_entity(int fd, void* entity, int size);
 void fill_buffer(size_t* written, char* dest, void *src, size_t n);
diff --git a/src/socks5.c b/src/socks5.c
index 1351cc4..a129cd4 100644
--- a/src/socks5.c
+++ b/src/socks5.c
@@ -1,105 +1,315 @@
 #include "socks5.h"
 
-int socks5_handshake_syn(int sock) {
-    //@TODO: Refactor the client handshake management
-    struct client_handshake ch = {
-      .ver = 0x05,
-      .nmethods = 0x01,
-      .methods = {0x00}
-    };
-
-    int size = sizeof(uint8_t) * (2 + ch.nmethods);
-    if (size != write(sock, &ch, size)) {
-        perror("write failed on tcp socket in socks5");
-        return -1;
-    }
-    return 0;
+void socks5_free_ctx(void* elem) {
+  struct socks5_ctx* ctx = elem;
+  free(ctx);
 }
 
-int socks5_handshake_ack(int sock) {
-    //@TODO: Refactor the client handshake management
-    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));
-    if (err == -1) {
-        perror("sock5 handshake failed read");
-        return -1;
-    }
-    if (ch.ver != sh.ver || sh.method != ch.methods[0]) {
-      fprintf(stderr, "Protocol error: client asks for ver=%d, method=%d and server answers with ver=%d, method=%d\n",
-              ch.ver, ch.methods[0], sh.ver, sh.method);
-      return -1;
-    }
-    printf("[server_handshake] ver=%d, method=%d\n", sh.ver, sh.method);
-    return 0;
+void socks5_create_dns_client(struct evt_core_ctx* ctx, char* proxy_host, char* proxy_port, char* addr, uint16_t port) {
+  struct evt_core_fdinfo fdinfo;
+  struct evt_core_cat cat;
+  struct socks5_ctx* s5ctx;
+  struct evt_core_fdinfo* reg_fdinfo;
+  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;
+  fdinfo.other = malloc(sizeof(struct socks5_ctx));
+  if (fdinfo.other == NULL) {
+    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;
+  s5ctx->port = port;
+  s5ctx->addr = strdup(addr);
+
+  // 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));
+
+  reg_fdinfo = evt_core_add_fd (ctx, &fdinfo);
 }
 
-int socks5_reply(int sock) {
-    int res;
-    struct server_reply sr = {0};
-    res = read_entity(sock, &sr, sizeof(uint8_t) * 4);
-    if (res == -1) goto read_error;
+int on_socks5_send_handshake(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+  struct socks5_ctx* s5ctx = fdinfo->other;
 
-    switch(sr.atyp) {
-        case ATYP_IPV4:
-            if (read_entity(sock, sr.bind_addr.ipv4, sizeof(uint8_t) * 4) == -1)
-                goto read_error;
-            break;
-        case ATYP_DOMAINNAME:
-            if (read_entity(sock, &sr.bind_addr.dns.len, sizeof(uint8_t) * 4) == -1)
-                goto read_error;
-            if (read_entity(sock, sr.bind_addr.dns.str, sizeof(char) * sr.bind_addr.dns.len) == -1)
-                goto read_error;
-            break;
-        case ATYP_IPV6:
-            if (read_entity(sock, sr.bind_addr.ipv6, sizeof(uint8_t) * 16) == -1)
-                goto read_error;
-            break;
-        default:
-            fprintf(stderr, "Unsupported ATYP in server reply\n");
-            return -128;
-    }
-    res = read_entity(sock, &sr.port, sizeof(uint16_t));
-    if (res == -1) {
-      perror("read_entity");
-      exit(EXIT_FAILURE);
-    }
+  size_t written = write(fdinfo->fd, (char*)&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 1;
+  }
+  s5ctx->ch_cursor += written;
+  if (s5ctx->ch_cursor < s5ctx->ch_size) return 0;
 
-    if (sr.rep < 0 || sr.rep > 0x08) {
-      fprintf(stderr, "Invalid reply field\n");
-      return -128;
-    }
-
-    printf("[server_reply] ver=%d, rep=%s, atyp=%d, port=%d\n", sr.ver, rep_msg[sr.rep], sr.atyp, sr.port);
-    return -sr.rep;
-
-read_error:
-    fprintf(stderr, "Unable to read ATYP\n");
-    return -128;
+  evt_core_mv_fd2(ctx, fdinfo, "socks5-recv-handshake");
+  return 1;
 }
 
-int socks5_connect_dns(int sock, char* addr, uint16_t port) {
-    char buffer[262];
-    size_t domainLength = strlen(addr);
-    if (domainLength > 255) {
-        fprintf(stderr, "domain is too long\n");
-        exit(EXIT_FAILURE);
-    }
-    struct client_request cr = { 0x05, CMD_CONNECT, 0x00, ATYP_DOMAINNAME, (uint8_t)domainLength, addr, htons(port) };
-    size_t written = 0;
-    fill_buffer(&written, buffer, &cr, 5*sizeof(uint8_t));
-    fill_buffer(&written, buffer, cr.dst_addr, cr.dst_addr_len*sizeof(char));
-    fill_buffer(&written, buffer, &cr.port, sizeof(uint16_t));
+int on_socks5_recv_handshake(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+  struct socks5_ctx* s5ctx = fdinfo->other;
+  int readn = 0;
 
-    if (written != write(sock, buffer, written)) {
-        fprintf(stderr, "partial/failed write\n");
-        return -1;
+  readn = read(fdinfo->fd, (char*)&s5ctx->sh + s5ctx->sh_cursor, sizeof(s5ctx->sh) - s5ctx->sh_cursor);
+  if (readn == -1 && errno == EAGAIN) return 1;
+  if (readn < 0) {
+    perror("sock5 handshake failed read");
+    evt_core_mv_fd2(ctx, fdinfo, "socks5-failed");
+    return 1;
+  }
+
+  s5ctx->sh_cursor += readn;
+  if (s5ctx->sh_cursor < sizeof(s5ctx->sh)) return 0;
+
+  if (s5ctx->ch.ver != s5ctx->sh.ver || s5ctx->sh.method != s5ctx->ch.methods[0]) {
+    fprintf(stderr, "Protocol error: client asks for ver=%d, method=%d and server answers with ver=%d, method=%d\n",
+              s5ctx->ch.ver, s5ctx->ch.methods[0], s5ctx->sh.ver, s5ctx->sh.method);
+    evt_core_mv_fd2(ctx, fdinfo, "socks5-failed");
+    return 1;
+  }
+  printf("[socks5_server_handshake] fd=%d, ver=%d, method=%d\n", fdinfo->fd, s5ctx->sh.ver, s5ctx->sh.method);
+  evt_core_mv_fd2(ctx, fdinfo, "socks5-send-client-req");
+  return 1;
+}
+
+int on_socks5_send_client_req(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+  struct socks5_ctx* s5ctx = fdinfo->other;
+  int written = 0;
+
+  written = write(fdinfo->fd, (char*)s5ctx->cr_buffer + s5ctx->cr_cursor, s5ctx->cr_size - s5ctx->cr_cursor);
+  if (written == -1 && errno == EAGAIN) return 1;
+  if (written < 0) {
+    fprintf(stderr, "socks5 send client request failed\n");
+    evt_core_mv_fd2 (ctx, fdinfo, "socks5-failed");
+    return 1;
+  }
+  s5ctx->cr_cursor += written;
+  if (s5ctx->cr_cursor < s5ctx->cr_size) return 0;
+
+  evt_core_mv_fd2 (ctx, fdinfo, "socks5-recv-server-reply");
+  return 1;
+}
+
+int socks5_server_reply_atyp_ipv4(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+  struct socks5_ctx* s5ctx = fdinfo->other;
+  size_t fixed_headers_size = (char*)&s5ctx->sr.bind_addr.ipv4 - (char*)&s5ctx->sr;
+  size_t host_size = sizeof(s5ctx->sr.bind_addr.ipv4);
+  uint64_t relative_cursor = (s5ctx->sr_cursor - fixed_headers_size);
+  int nread = 0;
+
+  nread = read(fdinfo->fd,
+       (char*)s5ctx->sr.bind_addr.ipv4 + relative_cursor,
+       host_size - relative_cursor);
+
+  if (nread == -1 && errno == EAGAIN) return 1;
+  if (nread < 0) {
+    perror("write failed on tcp socket in socks5");
+    evt_core_mv_fd2(ctx, fdinfo, "socks5-failed");
+    return 1;
+  }
+
+  s5ctx->sr_cursor += nread;
+  if (s5ctx->sr_cursor < fixed_headers_size + host_size) return 0;
+
+  s5ctx->sr_host_read = 1;
+  return 0;
+}
+
+int socks5_server_reply_atyp_ipv6(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+  struct socks5_ctx* s5ctx = fdinfo->other;
+  size_t fixed_headers_size = (char*)&s5ctx->sr.bind_addr.ipv6 - (char*)&s5ctx->sr;
+  size_t host_size = sizeof(s5ctx->sr.bind_addr.ipv6);
+  uint64_t relative_cursor = (s5ctx->sr_cursor - fixed_headers_size);
+  int nread = 0;
+
+  nread = read(fdinfo->fd,
+       (char*)s5ctx->sr.bind_addr.ipv6 + relative_cursor,
+       host_size - relative_cursor);
+
+  if (nread == -1 && errno == EAGAIN) return 1;
+  if (nread < 0) {
+    perror("write failed on tcp socket in socks5");
+    evt_core_mv_fd2(ctx, fdinfo, "socks5-failed");
+    return 1;
+  }
+  s5ctx->sr_cursor += nread;
+  if (s5ctx->sr_cursor < fixed_headers_size + host_size) return 0;
+
+  s5ctx->sr_host_read = 1;
+  return 0;
+}
+
+int socks5_server_reply_atyp_dn(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+  struct socks5_ctx* s5ctx = fdinfo->other;
+  size_t fixed_headers_size = (char*)&s5ctx->sr.bind_addr.ipv6 - (char*)&s5ctx->sr;
+  size_t dn_size_size = sizeof(s5ctx->sr.bind_addr.dns.len);
+  uint64_t relative_cursor = 0;
+  int nread = 0;
+
+  if (s5ctx->sr_cursor < fixed_headers_size + dn_size_size) {
+    relative_cursor = (s5ctx->sr_cursor - fixed_headers_size);
+    nread = read(fdinfo->fd, (char*)&s5ctx->sr.bind_addr.dns.len + relative_cursor, dn_size_size - relative_cursor);
+    if (nread == -1 && errno == EAGAIN) return 1;
+    if (nread < 0) {
+      perror("write failed on tcp socket in socks5");
+      evt_core_mv_fd2(ctx, fdinfo, "socks5-failed");
+      return 1;
     }
+    s5ctx->sr_cursor += nread;
     return 0;
+  }
+
+  relative_cursor = s5ctx->sr_cursor - fixed_headers_size - sizeof(s5ctx->sr.bind_addr.dns.len);
+  nread = read(fdinfo->fd, (char*)&s5ctx->sr.bind_addr.dns.str + relative_cursor, s5ctx->sr.bind_addr.dns.len - relative_cursor);
+  if (nread == -1 && errno == EAGAIN) return 1;
+  if (nread < 0) {
+    perror("write failed on tcp socket in socks5");
+    evt_core_mv_fd2(ctx, fdinfo, "socks5-failed");
+    return 1;
+  }
+  s5ctx->sr_cursor += nread;
+  if (s5ctx->sr_cursor < fixed_headers_size + dn_size_size + s5ctx->sr.bind_addr.dns.len) return 0;
+
+  s5ctx->sr_host_read = 1;
+  return 0;
+}
+
+size_t socks5_server_reply_size(struct server_reply* sr) {
+  size_t fixed_headers_size = (char*)&sr->bind_addr - (char*)sr;
+  size_t fixed_tail_size = (char*)(sr + 1) - (char*)&sr->port;
+  size_t host_size = 0;
+
+  if (sr->atyp == ATYP_IPV4) {
+    host_size = sizeof(sr->bind_addr.ipv4);
+  } else if (sr->atyp == ATYP_IPV6) {
+    host_size = sizeof(sr->bind_addr.ipv6);
+  } else if (sr->atyp == ATYP_DOMAINNAME) {
+    host_size = sizeof(sr->bind_addr.dns.len) + sr->bind_addr.dns.len;
+  } else {
+    fprintf(stderr, "Unsupported ATYP for SOCK5\n");
+    exit(EXIT_FAILURE);
+  }
+
+  return fixed_headers_size + host_size + fixed_tail_size;
+}
+
+int on_socks5_recv_server_reply(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+  struct socks5_ctx* s5ctx = fdinfo->other;
+  int readn = 0;
+  size_t fixed_headers_size = (char*)&s5ctx->sr.bind_addr - (char*)&s5ctx->sr;
+
+  // Read headers
+  if (s5ctx->sr_cursor < fixed_headers_size) {
+    readn = read(fdinfo->fd, (char*)&s5ctx->sr + s5ctx->sr_cursor, fixed_headers_size - s5ctx->sr_cursor);
+    if (readn == -1 && errno == EAGAIN) return 1;
+    if (readn < 0) goto move_to_failed;
+    s5ctx->sr_cursor += readn;
+    return 0; // Needed as we might have not read enough bytes and free us from writing a loop
+  }
+
+  // Read host
+  if (!s5ctx->sr_host_read) {
+    if (s5ctx->sr.atyp == ATYP_IPV4) return socks5_server_reply_atyp_ipv4(ctx, fdinfo);
+    else if (s5ctx->sr.atyp == ATYP_IPV6) return socks5_server_reply_atyp_ipv6(ctx, fdinfo);
+    else if (s5ctx->sr.atyp == ATYP_DOMAINNAME) return socks5_server_reply_atyp_dn(ctx, fdinfo);
+    else goto move_to_failed;
+  }
+
+  // Read port
+  size_t final_size = socks5_server_reply_size(&s5ctx->sr);
+  if (s5ctx->sr_cursor < final_size) {
+    size_t relative_cursor = s5ctx->sr_cursor - (final_size - sizeof(s5ctx->sr.port));
+    readn = read(fdinfo->fd, (char*)&s5ctx->sr.port + relative_cursor, sizeof(s5ctx->sr.port) - relative_cursor);
+    if (readn == -1 && errno == EAGAIN) return 1;
+    if (readn < 0) goto move_to_failed;
+    s5ctx->sr_cursor += readn;
+    return 0; // Needed as we might have not read enough bytes and free us from writing a loop
+  }
+
+  // Do some checks
+  if (s5ctx->sr.rep > 0x08) goto move_to_failed;
+  printf("[socks5_server_reply] fd=%d, ver=%d, rep=%s, atyp=%d, port=%d\n", fdinfo->fd, s5ctx->sr.ver, rep_msg[s5ctx->sr.rep], s5ctx->sr.atyp, s5ctx->sr.port);
+
+  if (s5ctx->sr.rep != SOCKS5_REP_SUCCESS) goto move_to_failed;
+
+  evt_core_mv_fd2 (ctx, fdinfo, "socks5-success");
+  return 1;
+move_to_failed:
+  evt_core_mv_fd2 (ctx, fdinfo, "socks5-failed");
+  return 1;
+}
+
+int on_socks5_err(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+  evt_core_mv_fd2 (ctx, fdinfo, "socks5-failed");
+  return 1;
+}
+
+void socks5_init(struct evt_core_ctx* ctx) {
+  struct evt_core_cat template = {0};
+
+  template.cb = on_socks5_send_handshake;
+  template.err_cb = on_socks5_err;
+  template.name = "socks5-send-handshake";
+  template.flags = EPOLLOUT | EPOLLET;
+  evt_core_add_cat (ctx, &template);
+
+  template.cb = on_socks5_recv_handshake;
+  template.err_cb = on_socks5_err;
+  template.name = "socks5-recv-handshake";
+  template.flags = EPOLLIN | EPOLLET;
+  evt_core_add_cat (ctx, &template);
+
+  template.cb = on_socks5_send_client_req;
+  template.err_cb = on_socks5_err;
+  template.name = "socks5-send-client-req";
+  template.flags = EPOLLOUT | EPOLLET;
+  evt_core_add_cat(ctx, &template);
+
+  template.cb = on_socks5_recv_server_reply;
+  template.err_cb = on_socks5_err;
+  template.name =  "socks5-recv-server-reply";
+  template.flags = EPOLLIN | EPOLLET;
+  evt_core_add_cat(ctx, &template);
 }
 
 char* socks5_rep (enum socks5_rep rep) {
diff --git a/src/socks5.h b/src/socks5.h
index 742f663..1d84a14 100644
--- a/src/socks5.h
+++ b/src/socks5.h
@@ -7,6 +7,7 @@
 #include <netdb.h>
 #include <string.h>
 #include "net_tools.h"
+#include "evt_core.h"
 
 enum socks5_state {
   SOCKS5_STATE_NEW,
@@ -27,10 +28,21 @@ 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;
-        char* str;
+        char str[256];
     } dns;
     uint8_t ipv4[4];
     uint8_t ipv6[16];
@@ -95,8 +107,24 @@ struct server_reply {
     uint16_t port;
 };
 
-int socks5_handshake_syn(int sock);
-int socks5_handshake_ack(int sock);
-int socks5_connect_dns(int sock, char* addr, uint16_t port);
-int socks5_reply(int sock);
+struct socks5_ctx {
+  uint16_t port;
+  char* addr;
+
+  struct client_handshake ch;
+  struct server_handshake sh;
+  struct client_request cr;
+  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;
+  uint8_t sr_host_read;
+};
+
+void socks5_init(struct evt_core_ctx* ctx);
+void socks5_create_dns_client(struct evt_core_ctx* ctx, char* proxy_host, char* proxy_port, char* addr, uint16_t port);
 char* socks5_rep (enum socks5_rep rep);
diff --git a/src/tor_echo.c b/src/tor_echo.c
index 6457576..2436b4c 100644
--- a/src/tor_echo.c
+++ b/src/tor_echo.c
@@ -37,6 +37,7 @@ int te_on_tcp_co(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
   in_len = sizeof(addr);
   conn_sock1 = accept(fdinfo->fd, (struct sockaddr*)&addr, &in_len);
 
+  if (conn_sock1 == -1 && errno == EAGAIN) return 1;
   if (conn_sock1 == -1) goto co_error;
 
   url_get_port(port, fdinfo->url);
@@ -46,7 +47,7 @@ int te_on_tcp_co(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
   sprintf(to_fdinfo.url, "tcp:all:127.0.0.1:%s", port);
   evt_core_add_fd (ctx, &to_fdinfo);
 
-  return 1;
+  return 0;
 
 co_error:
   perror("Failed to handle new connection");