add a utility function to detect redirects and handle them

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

4 files changed, 50 insertions, 5 deletions

diff --git a/uclient-backend.h b/uclient-backend.h
index abbfbc6..fdebf26 100644
--- a/uclient-backend.h
+++ b/uclient-backend.h
@@ -31,5 +31,6 @@ struct uclient_url {
 void uclient_backend_set_error(struct uclient *cl);
 void uclient_backend_set_eof(struct uclient *cl);
 void uclient_backend_reset_state(struct uclient *cl);
+struct uclient_url *uclient_get_url(const char *url_str, const char *auth_str);
 
 #endif
diff --git a/uclient-http.c b/uclient-http.c
index b6f28e1..0ce43c2 100644
--- a/uclient-http.c
+++ b/uclient-http.c
@@ -850,6 +850,44 @@ uclient_http_read(struct uclient *cl, char *buf, unsigned int len)
 	return len;
 }
 
+bool uclient_http_redirect(struct uclient *cl)
+{
+	struct uclient_http *uh = container_of(cl, struct uclient_http, uc);
+	struct blobmsg_policy location = {
+		.name = "location",
+		.type = BLOBMSG_TYPE_STRING,
+	};
+	struct uclient_url *url = cl->url;
+	struct blob_attr *tb;
+
+	if (cl->backend != &uclient_backend_http)
+		return false;
+
+	switch (cl->status_code) {
+	case 301:
+	case 302:
+	case 307:
+		break;
+	default:
+		return false;
+	}
+
+	blobmsg_parse(&location, 1, &tb, blob_data(uh->meta.head), blob_len(uh->meta.head));
+	if (!tb)
+		return false;
+
+	url = uclient_get_url(blobmsg_data(tb), url->auth);
+	if (!url)
+		return false;
+
+	free(cl->url);
+	cl->url = url;
+	uclient_http_connect(cl);
+	uclient_http_request_done(cl);
+
+	return true;
+}
+
 const struct uclient_backend uclient_backend_http = {
 	.prefix = uclient_http_prefix,
 
diff --git a/uclient.c b/uclient.c
index 9453365..e7213a1 100644
--- a/uclient.c
+++ b/uclient.c
@@ -3,7 +3,8 @@
 #include "uclient-utils.h"
 #include "uclient-backend.h"
 
-static struct uclient_url *uclient_get_url(const char *url_str)
+struct uclient_url * __hidden
+uclient_get_url(const char *url_str, const char *auth_str)
 {
 	static const struct uclient_backend *backends[] = {
 		&uclient_backend_http,
@@ -13,7 +14,7 @@ static struct uclient_url *uclient_get_url(const char *url_str)
 	const char * const *prefix = NULL;
 	struct uclient_url *url;
 	const char *location;
-	char *host_buf, *uri_buf, *next;
+	char *host_buf, *uri_buf, *auth_buf, *next;
 	int i, host_len;
 
 	for (i = 0; i < ARRAY_SIZE(backends); i++) {
@@ -48,7 +49,8 @@ static struct uclient_url *uclient_get_url(const char *url_str)
 
 	url = calloc_a(sizeof(*url),
 		&host_buf, host_len + 1,
-		&uri_buf, strlen(location) + 1);
+		&uri_buf, strlen(location) + 1,
+		&auth_buf, auth_str ? strlen(auth_str) + 1 : 0);
 
 	url->backend = backend;
 	url->location = strcpy(uri_buf, location);
@@ -66,6 +68,9 @@ static struct uclient_url *uclient_get_url(const char *url_str)
 		url->auth = host_buf;
 	}
 
+	if (!url->auth && auth_str)
+		url->auth = strcpy(auth_buf, auth_str);
+
 	/* Literal IPv6 address */
 	if (*url->host == '[') {
 		url->host++;
@@ -94,7 +99,7 @@ struct uclient *uclient_new(const char *url_str, const struct uclient_cb *cb)
 	struct uclient *cl;
 	struct uclient_url *url;
 
-	url = uclient_get_url(url_str);
+	url = uclient_get_url(url_str, NULL);
 	if (!url)
 		return NULL;
 
@@ -115,7 +120,7 @@ int uclient_connect_url(struct uclient *cl, const char *url_str)
 	const struct uclient_backend *backend = cl->backend;
 
 	if (url_str) {
-		url = uclient_get_url(url_str);
+		url = uclient_get_url(url_str, NULL);
 		if (!url)
 			return -1;
 
diff --git a/uclient.h b/uclient.h
index f4009e0..e3d168a 100644
--- a/uclient.h
+++ b/uclient.h
@@ -52,5 +52,6 @@ extern const struct uclient_backend uclient_backend_http;
 int uclient_http_set_header(struct uclient *cl, const char *name, const char *value);
 int uclient_http_reset_headers(struct uclient *cl, const char *name, const char *value);
 int uclient_http_set_request_type(struct uclient *cl, const char *type);
+bool uclient_http_redirect(struct uclient *cl);
 
 #endif