http: support sending custom HTTP headers
We introduce a way to send custom HTTP headers with all requests.
This allows us, for example, to send an extra token from build agents
for temporary access to private repositories. (This is the use case that
triggered this patch.)
This feature can be used like this:
git -c http.extraheader='Secret: sssh!' fetch $URL $REF
Note that `curl_easy_setopt(..., CURLOPT_HTTPHEADER, ...)` takes only
a single list, overriding any previous call. This means we have to
collect _all_ of the headers we want to use into a single list, and
feed it to cURL in one shot. Since we already unconditionally set a
"pragma" header when initializing the curl handles, we can add our new
headers to that list.
For callers which override the default header list (like probe_rpc),
we provide `http_copy_default_headers()` so they can do the same
trick.
Big thanks to Jeff King and Junio Hamano for their outstanding help and
patient reviews.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/http.c b/http.c
index 69da445..aae9944 100644
--- a/http.c
+++ b/http.c
@@ -114,6 +114,7 @@
static struct curl_slist *pragma_header;
static struct curl_slist *no_pragma_header;
+static struct curl_slist *extra_http_headers;
static struct active_request_slot *active_queue_head;
@@ -323,6 +324,19 @@
#endif
}
+ if (!strcmp("http.extraheader", var)) {
+ if (!value) {
+ return config_error_nonbool(var);
+ } else if (!*value) {
+ curl_slist_free_all(extra_http_headers);
+ extra_http_headers = NULL;
+ } else {
+ extra_http_headers =
+ curl_slist_append(extra_http_headers, value);
+ }
+ return 0;
+ }
+
/* Fall back on the default ones */
return git_default_config(var, value, cb);
}
@@ -675,8 +689,10 @@
if (remote)
var_override(&http_proxy_authmethod, remote->http_proxy_authmethod);
- pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
- no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
+ pragma_header = curl_slist_append(http_copy_default_headers(),
+ "Pragma: no-cache");
+ no_pragma_header = curl_slist_append(http_copy_default_headers(),
+ "Pragma:");
#ifdef USE_CURL_MULTI
{
@@ -762,6 +778,9 @@
#endif
curl_global_cleanup();
+ curl_slist_free_all(extra_http_headers);
+ extra_http_headers = NULL;
+
curl_slist_free_all(pragma_header);
pragma_header = NULL;
@@ -1160,6 +1179,16 @@
return handle_curl_result(results);
}
+struct curl_slist *http_copy_default_headers(void)
+{
+ struct curl_slist *headers = NULL, *h;
+
+ for (h = extra_http_headers; h; h = h->next)
+ headers = curl_slist_append(headers, h->data);
+
+ return headers;
+}
+
static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
{
char *ptr;
@@ -1377,7 +1406,7 @@
{
struct active_request_slot *slot;
struct slot_results results;
- struct curl_slist *headers = NULL;
+ struct curl_slist *headers = http_copy_default_headers();
struct strbuf buf = STRBUF_INIT;
const char *accept_language;
int ret;
