Implement serverConnect

1 files changed, 71 insertions, 0 deletions

diff --git a/server.c b/server.c
new file mode 100644
index 0000000..b86d769
--- /dev/null
+++ b/server.c
@@ -0,0 +1,71 @@
+/* Copyright (C) 2019  C. McEnroe <june@causal.agency>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <err.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <stdlib.h>
+#include <sys/socket.h>
+#include <sysexits.h>
+#include <tls.h>
+#include <unistd.h>
+
+#include "bounce.h"
+
+static struct tls *client;
+
+int serverConnect(const char *host, const char *port) {
+	int error;
+
+	struct tls_config *config = tls_config_new();
+	error = tls_config_set_ciphers(config, "compat");
+	if (error) errx(EX_SOFTWARE, "tls_config");
+
+	client = tls_client();
+	if (!client) errx(EX_SOFTWARE, "tls_client");
+
+	error = tls_configure(client, config);
+	if (error) errx(EX_SOFTWARE, "tls_configure: %s", tls_error(client));
+	tls_config_free(config);
+
+	struct addrinfo *head;
+	struct addrinfo hints = {
+		.ai_family = AF_UNSPEC,
+		.ai_socktype = SOCK_STREAM,
+		.ai_protocol = IPPROTO_TCP,
+	};
+	error = getaddrinfo(host, port, &hints, &head);
+	if (error) errx(EX_NOHOST, "%s:%s: %s", host, port, gai_strerror(error));
+
+	int sock = -1;
+	for (struct addrinfo *ai = head; ai; ai = ai->ai_next) {
+		sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
+		if (sock < 0) err(EX_OSERR, "socket");
+
+		error = connect(sock, ai->ai_addr, ai->ai_addrlen);
+		if (!error) break;
+
+		close(sock);
+		sock = -1;
+	}
+	if (sock < 0) err(EX_UNAVAILABLE, "%s:%s", host, port);
+	freeaddrinfo(head);
+
+	error = tls_connect_socket(client, sock, host);
+	if (error) errx(EX_PROTOCOL, "tls_connect: %s", tls_error(client));
+
+	return sock;
+}