Merge pull request #100 from painless-security/milestone/monitoring

[trust_router.git] / common / tr_gss_client.c

diff --git a/common/tr_gss_client.c b/common/tr_gss_client.c
new file mode 100644 (file)
index 0000000..f45af3a
--- /dev/null
+++ b/common/tr_gss_client.c
@@ -0,0 +1,140 @@
+/*
+ * Copyright (c) 2012, 2014-2018, JANET(UK)
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of JANET(UK) nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <talloc.h>
+
+#include <trust_router/tr_dh.h>
+#include <tr_msg.h>
+#include <gsscon.h>
+#include <tr_debug.h>
+#include <tr_gss_client.h>
+
+TR_GSSC_INSTANCE *tr_gssc_instance_new(TALLOC_CTX *mem_ctx)
+{
+  TR_GSSC_INSTANCE *gssc=talloc(NULL, TR_GSSC_INSTANCE);
+  if (gssc != NULL) {
+    gssc->service_name = NULL;
+    gssc->conn = -1;
+    gssc->gss_ctx = talloc(gssc, gss_ctx_id_t);
+    if (gssc->gss_ctx == NULL) {
+      talloc_free(gssc);
+      return NULL;
+    }
+  }
+  return gssc;
+}
+
+void tr_gssc_instance_free(TR_GSSC_INSTANCE *tr_gssc)
+{
+  talloc_free(tr_gssc);
+}
+
+/**
+ * Open a connection to the requested server:port
+ *
+ * @param gssc client instance
+ * @param server server name/address
+ * @param port TCP port to connect
+ * @return 0 on success, -1 on failure
+ */
+int tr_gssc_open_connection(TR_GSSC_INSTANCE *gssc, const char *server, int port)
+{
+  if ((port <= 0) || (port > 65535)) {
+    tr_err("tr_gssc_open_connection: invalid port requested (%d)", port);
+    return -1;
+  }
+
+  tr_debug("tr_gssc_open_connection: opening connection to %s:%d", server, port);
+  if (0 != gsscon_connect(server, (unsigned int) port, gssc->service_name, &(gssc->conn), gssc->gss_ctx))
+    return -1;
+
+  return 0; /* success */
+}
+
+/**
+ * Send a request message and retrieve a response message
+ *
+ * @param mem_ctx
+ * @param gssc
+ * @param req_msg
+ * @return decoded message, or null on error
+ */
+TR_MSG *tr_gssc_exchange_msgs(TALLOC_CTX *mem_ctx, TR_GSSC_INSTANCE *gssc, TR_MSG *req_msg)
+{
+  TALLOC_CTX *tmp_ctx = talloc_new(NULL);
+  char *req_buf = NULL;
+  char *resp_buf = NULL;
+  size_t resp_buflen = 0;
+  TR_MSG *resp_msg = NULL; /* this is the return value */
+  int err;
+
+  /* Validate inputs */
+  if ((gssc == NULL) || (req_msg == NULL))
+    goto cleanup;
+
+  /* Encode the request into a json string */
+  if (!(req_buf = tr_msg_encode(tmp_ctx, req_msg))) {
+    tr_err("tr_gssc_exchange_msgs: Error encoding request message.\n");
+    goto cleanup;
+  }
+
+  tr_debug( "tr_gssc_exchange_msgs: Sending request message:\n%s\n", req_buf);
+
+  /* Send the request over the connection */
+  err = gsscon_write_encrypted_token(gssc->conn, *(gssc->gss_ctx), req_buf, strlen(req_buf));
+  if (err) {
+    tr_err( "tr_gssc_exchange_msgs: Error sending request.\n");
+    goto cleanup;
+  }
+
+  /* Read the response from the connection */
+  /* TBD -- timeout? */
+  if (gsscon_read_encrypted_token(gssc->conn, *(gssc->gss_ctx), &resp_buf, &resp_buflen))
+    goto cleanup;
+
+  tr_debug( "tr_gssc_exchange_msgs: Response Received (%u bytes).\n%s\n", (unsigned) resp_buflen, resp_buf);
+  resp_msg = tr_msg_decode(mem_ctx, resp_buf, resp_buflen);
+  free(resp_buf);
+
+  if (resp_msg == NULL) {
+    tr_err( "tr_gssc_exchange_msgs: Error decoding response.\n");
+    goto cleanup;
+  }
+
+  /* If we get here, then we decoded the message and resp_msg is not null. Nothing more to do. */
+
+cleanup:
+  talloc_free(tmp_ctx);
+  return resp_msg;
+}