From f50a654323bbfeb0de53aa2178755b282bcc9d22 Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@openwrt.org>
Date: Mon, 25 Jan 2016 00:18:33 +0100
Subject: [PATCH] http: add support for specifying ipv4/ipv6 preference

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
---
 uclient-fetch.c | 17 +++++++++++++++--
 uclient-http.c  | 27 ++++++++++++++++++++++++++-
 uclient.h       |  1 +
 3 files changed, 42 insertions(+), 3 deletions(-)

diff --git a/uclient-fetch.c b/uclient-fetch.c
index 851994f..f65fab2 100644
--- a/uclient-fetch.c
+++ b/uclient-fetch.c
@@ -18,6 +18,7 @@
 
 #define _GNU_SOURCE
 #include <sys/stat.h>
+#include <sys/socket.h>
 #include <unistd.h>
 #include <stdio.h>
 #include <dlfcn.h>
@@ -439,6 +440,8 @@ static int usage(const char *progname)
 	fprintf(stderr,
 		"Usage: %s [options] <URL>\n"
 		"Options:\n"
+		"	-4:				Use IPv4 only\n"
+		"	-6:				Use IPv6 only\n"
 		"	-q:                             Turn off status messages\n"
 		"	-O <file>:                      Redirect output to file (use \"-\" for stdout)\n"
 		"	-P <dir>:			Set directory for output files\n"
@@ -530,11 +533,12 @@ int main(int argc, char **argv)
 	bool has_cert = false;
 	int i, ch;
 	int rc;
+	int af = -1;
 
 	signal(SIGPIPE, SIG_IGN);
 	init_ustream_ssl();
 
-	while ((ch = getopt_long(argc, argv, "cO:P:qsT:U:Y:", longopts, &longopt_idx)) != -1) {
+	while ((ch = getopt_long(argc, argv, "46cO:P:qsT:U:Y:", longopts, &longopt_idx)) != -1) {
 		switch(ch) {
 		case 0:
 			switch (longopt_idx) {
@@ -584,6 +588,12 @@ int main(int argc, char **argv)
 				return usage(progname);
 			}
 			break;
+		case '4':
+			af = AF_INET;
+			break;
+		case '6':
+			af = AF_INET6;
+			break;
 		case 'c':
 			resume = true;
 			break;
@@ -652,7 +662,8 @@ int main(int argc, char **argv)
 	proxy_url = get_proxy_url(argv[0]);
 	if (proxy_url) {
 		cl = uclient_new(proxy_url, auth_str, &cb);
-		uclient_set_proxy_url(cl, argv[0], NULL);
+		if (cl)
+		    uclient_set_proxy_url(cl, argv[0], NULL);
 	} else {
 		cl = uclient_new(argv[0], auth_str, &cb);
 	}
@@ -660,6 +671,8 @@ int main(int argc, char **argv)
 		fprintf(stderr, "Failed to allocate uclient context\n");
 		return 1;
 	}
+	if (af >= 0)
+	    uclient_http_set_address_family(cl, af);
 
 	if (ssl_ctx && default_certs)
 		init_ca_cert();
diff --git a/uclient-http.c b/uclient-http.c
index 5e5f996..f080e41 100644
--- a/uclient-http.c
+++ b/uclient-http.c
@@ -15,6 +15,7 @@
  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
+#include <sys/socket.h>
 #include <stdio.h>
 #include <ctype.h>
 #include <unistd.h>
@@ -90,6 +91,8 @@ struct uclient_http {
 	long read_chunked;
 	long content_length;
 
+	int usock_flags;
+
 	uint32_t nc;
 
 	struct blob_buf headers;
@@ -120,7 +123,7 @@ static int uclient_do_connect(struct uclient_http *uh, const char *port)
 
 	memset(&uh->uc.remote_addr, 0, sizeof(uh->uc.remote_addr));
 
-	fd = usock_inet(USOCK_TCP, uh->uc.url->host, port, &uh->uc.remote_addr);
+	fd = usock_inet(USOCK_TCP | uh->usock_flags, uh->uc.url->host, port, &uh->uc.remote_addr);
 	if (fd < 0)
 		return -1;
 
@@ -1129,6 +1132,28 @@ int uclient_http_set_ssl_ctx(struct uclient *cl, const struct ustream_ssl_ops *o
 	return 0;
 }
 
+int uclient_http_set_address_family(struct uclient *cl, int af)
+{
+	struct uclient_http *uh = container_of(cl, struct uclient_http, uc);
+
+	if (cl->backend != &uclient_backend_http)
+		return -1;
+
+	switch (af) {
+	case AF_INET:
+		uh->usock_flags = USOCK_IPV4ONLY;
+		break;
+	case AF_INET6:
+		uh->usock_flags = USOCK_IPV6ONLY;
+		break;
+	default:
+		uh->usock_flags = 0;
+		break;
+	}
+
+	return 0;
+}
+
 const struct uclient_backend uclient_backend_http = {
 	.prefix = uclient_http_prefix,
 
diff --git a/uclient.h b/uclient.h
index 504fc35..e3695db 100644
--- a/uclient.h
+++ b/uclient.h
@@ -125,5 +125,6 @@ int uclient_http_redirect(struct uclient *cl);
 
 int uclient_http_set_ssl_ctx(struct uclient *cl, const struct ustream_ssl_ops *ops,
 			     struct ustream_ssl_ctx *ctx, bool require_validation);
+int uclient_http_set_address_family(struct uclient *cl, int af);
 
 #endif
-- 
2.25.1