Migrate from callbacks to sockopts

Changes in main.c, remove the callback functions. Change the structure
in on_conn() function. Use setsockopt() and getsockopt() to set or get
handshake parameters.

This is a series of commits that are related to issue:enarx-archive#33, enarx-archive#34

bin/main.c

@@ -120,29 +120,6 @@ keydup(const options_t *o, uint8_t **key)
   return size;
 }
 
-static ssize_t
-srv_psk_cb(void *m, const char *username, uint8_t **key)
-{
-  const options_t *o = m;
-
-  if (strcmp(username, o->psku) != 0)
-    return -1;
-
-  return keydup(o, key);
-}
-
-static ssize_t
-clt_psk_cb(void *m, char **username, uint8_t **key)
-{
-  const options_t *o = m;
-
-  *username = strdup(o->psku);
-  if (!*username)
-    return -1;
-
-  return keydup(o, key);
-}
-
 static status_t
 on_conn(options_t *opts, int con, int in, int out, const struct addrinfo *ai)
 {
@@ -154,31 +131,91 @@ on_conn(options_t *opts, int con, int in, int out, const struct addrinfo *ai)
 
   if (ai->ai_protocol == IPPROTO_TLS) {
     int ret;
+    int true_indicator = 1;
+    int false_indicator = 0;
+    socklen_t *val_len = NULL;
+    size_t size;
+    const char *user = NULL;
+    uint8_t **key = NULL;
 
     if (opts->listen) {
-      tls_srv_handshake_t srv = { .misc = opts };
-
-      if (opts->psku)
-        srv.psk = srv_psk_cb;
-
       ret = non_setsockopt(con, IPPROTO_TLS,
-                           TLS_SRV_HANDSHAKE, &srv, sizeof(srv));
+                           TLS_IS_SERVER, &true_indicator, sizeof(true_indicator));
+
+      if (ret != 0)
+      goto fail;
+
+      if (opts->psku) {
+        ret = non_setsockopt(con, IPPROTO_TLS,
+                             TLS_PSK, &true_indicator, sizeof(true_indicator));
+        }
+
+      if (ret != 0)
+        goto fail;
+
+      while (handshake(con) == -1) {
+        fprintf(stderr, "Entering server handshake function.\nErrno is %d\n", errno);
+        switch (errno) {
+          case ENOKEY:
+            ret = getsockopt(con, IPPROTO_TLS,
+                             TLS_PSK_USER, &user, val_len);
+
+            if (ret != 0 || *val_len != strlen(user))
+              goto fail;
+            else {
+              if (strcmp(user, opts->psku) == 0) {
+                size = keydup(opts, key);
+                ret = non_setsockopt(con, IPPROTO_TLS,
+                                     TLS_PSK_KEY, key, size);
+                if (ret != 0)
+                  goto fail;
+              }
+            }
+            break;
+        }
+      }
     } else {
-      tls_clt_handshake_t clt = { .misc = opts };
-
-      if (opts->psku)
-        clt.psk = clt_psk_cb;
-
       ret = non_setsockopt(con, IPPROTO_TLS,
-                           TLS_CLT_HANDSHAKE, &clt, sizeof(clt));
+                           TLS_IS_SERVER, &false_indicator, sizeof(false_indicator));
+
+      if (ret != 0)
+      goto fail;
+
+      while (handshake(con) == -1) {
+        int val;
+        fprintf(stderr, "Entering client handshake function.\nErrno is %d.\n", errno);
+        switch (errno) {
+          case ENOKEY:
+            ret = getsockopt(con, IPPROTO_TLS,
+                             TLS_PSK, &val, val_len);
+
+            if (ret != 0)
+              goto fail;
+
+            if (val) {
+              ret = non_setsockopt(con, IPPROTO_TLS, TLS_PSK_USER,
+                                   opts->psku, strlen(opts->psku));
+              if (ret != 0)
+                goto fail;
+
+              size = keydup(opts, key);
+              ret = non_setsockopt(con, IPPROTO_TLS,
+                                   TLS_PSK_KEY, key, size);
+              if (ret != 0)
+                goto fail;
+            }
+            break;
+        }
+      }
     }
 
-    if (ret != 0) {
+  fail:
       fprintf(stderr, "%m: Unable to complete TLS handshake!\n");
       shutdown(con, SHUT_RDWR);
       return STATUS_FAILURE;
     }
-  }
+
+  //fprintf(stderr, "Complete TLS handshake!\n");
 
   while (poll(pfds, 2, -1) >= 0) {
     char buffer[64 * 1024] = {};