http: hoist credential request out of handle_curl_result

When we are handling a curl response code in http_request or
in the remote-curl RPC code, we use the handle_curl_result
helper to translate curl's response into an easy-to-use
code. When we see an HTTP 401, we do one of two things:

1. If we already had a filled-in credential, we mark it as
rejected, and then return HTTP_NOAUTH to indicate to
the caller that we failed.

2. If we didn't, then we ask for a new credential and tell
the caller HTTP_REAUTH to indicate that they may want
to try again.

Rejecting in the first case makes sense; it is the natural
result of the request we just made. However, prompting for
more credentials in the second step does not always make
sense. We do not know for sure that the caller is going to
make a second request, and nor are we sure that it will be
to the same URL. Logically, the prompt belongs not to the
request we just finished, but to the request we are (maybe)
about to make.

In practice, it is very hard to trigger any bad behavior.
Currently, if we make a second request, it will always be to
the same URL (even in the face of redirects, because curl
handles the redirects internally). And we almost always
retry on HTTP_REAUTH these days. The one exception is if we
are streaming a large RPC request to the server (e.g., a
pushed packfile), in which case we cannot restart. It's
extremely unlikely to see a 401 response at this stage,
though, as we would typically have seen it when we sent a
probe request, before streaming the data.

This patch drops the automatic prompt out of case 2, and
instead requires the caller to do it. This is a few extra
lines of code, and the bug it fixes is unlikely to come up
in practice. But it is conceptually cleaner, and paves the
way for better handling of credentials across redirects.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>

diff --git a/http.c b/http.c
index 6bb2e456ff7a26f33038bde8acc4dd9089cbb858..5703074d95d1e1782c754b28921ccde9d7b28c57 100644 (file)
--- a/http.c
+++ b/http.c
@@ -45,7 +45,7 @@ static long curl_low_speed_time = -1;
 static int curl_ftp_no_epsv;
 static const char *curl_http_proxy;
 static const char *curl_cookie_file;
-static struct credential http_auth = CREDENTIAL_INIT;
+struct credential http_auth = CREDENTIAL_INIT;
 static int http_proactive_auth;
 static const char *user_agent;
 
@@ -806,7 +806,6 @@ int handle_curl_result(struct slot_results *results)
                        credential_reject(&http_auth);
                        return HTTP_NOAUTH;
                } else {
-                       credential_fill(&http_auth);
                        return HTTP_REAUTH;
                }
        } else {
@@ -924,6 +923,9 @@ static int http_request_reauth(const char *url,
                        die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
                }
        }
+
+       credential_fill(&http_auth);
+
        return http_request(url, result, target, options);
 }
 

diff --git a/http.h b/http.h
index 40404b4836b5599bff75badc9e762d6e8594665f..17116abc570bf3d5577051420d88d839a9603e80 100644 (file)
--- a/http.h
+++ b/http.h
@@ -102,6 +102,7 @@ extern void http_cleanup(void);
 extern int active_requests;
 extern int http_is_verbose;
 extern size_t http_post_buffer;
+extern struct credential http_auth;
 
 extern char curl_errorstr[CURL_ERROR_SIZE];
 

diff --git a/remote-curl.c b/remote-curl.c
index ed1499b62cbf76001cdaa6db0595d613862ee3c1..8ffd7ff7a7189ce2022a49ef808b43024b04dcc2 100644 (file)
--- a/remote-curl.c
+++ b/remote-curl.c
@@ -8,6 +8,7 @@
 #include "pkt-line.h"
 #include "sideband.h"
 #include "argv-array.h"
+#include "credential.h"
 
 static struct remote *remote;
 static const char *url; /* always ends with a trailing slash */
@@ -449,6 +450,8 @@ static int post_rpc(struct rpc_state *rpc)
        if (large_request) {
                do {
                        err = probe_rpc(rpc);
+                       if (err == HTTP_REAUTH)
+                               credential_fill(&http_auth);
                } while (err == HTTP_REAUTH);
                if (err != HTTP_OK)
                        return -1;
@@ -548,8 +551,10 @@ static int post_rpc(struct rpc_state *rpc)
        curl_easy_setopt(slot->curl, CURLOPT_FILE, rpc);
 
        err = run_slot(slot);
-       if (err == HTTP_REAUTH && !large_request)
+       if (err == HTTP_REAUTH && !large_request) {
+               credential_fill(&http_auth);
                goto retry;
+       }
        if (err != HTTP_OK)
                err = -1;