From 467e2cb1d71b9ec01878e05f71d50e87f110ec89 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Carlos=20Mart=C3=ADn=20Nieto?= <cmn@dwim.me>
Date: Fri, 2 Oct 2015 10:11:43 +0200
Subject: [PATCH] curl: ask for proxy credentials

---
 src/curl_stream.c | 85 ++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 81 insertions(+), 4 deletions(-)

diff --git a/src/curl_stream.c b/src/curl_stream.c
index f48dd2249..98de187dd 100644
--- a/src/curl_stream.c
+++ b/src/curl_stream.c
@@ -23,6 +23,7 @@ typedef struct {
 	git_cert_x509 cert_info;
 	git_strarray cert_info_strings;
 	git_proxy_options proxy;
+	git_cred *proxy_cred;
 } curl_stream;
 
 static int seterr_curl(curl_stream *s)
@@ -31,21 +32,94 @@ static int seterr_curl(curl_stream *s)
 	return -1;
 }
 
+GIT_INLINE(int) error_no_credentials(void)
+{
+	giterr_set(GITERR_NET, "proxy authentication required, but no callback provided");
+	return GIT_EAUTH;
+}
+
+static int apply_proxy_creds(curl_stream *s)
+{
+	CURLcode res;
+	git_cred_userpass_plaintext *userpass;
+
+	if (!s->proxy_cred)
+		return GIT_ENOTFOUND;
+
+	userpass = (git_cred_userpass_plaintext *) s->proxy_cred;
+	if ((res = curl_easy_setopt(s->handle, CURLOPT_PROXYUSERNAME, userpass->username)) != CURLE_OK)
+		return seterr_curl(s);
+	if ((res = curl_easy_setopt(s->handle, CURLOPT_PROXYPASSWORD, userpass->password)) != CURLE_OK)
+		return seterr_curl(s);
+
+	return 0;
+}
+
+static int ask_and_apply_proxy_creds(curl_stream *s)
+{
+	int error;
+	git_proxy_options *opts = &s->proxy;
+
+	if (!opts->credentials)
+		return error_no_credentials();
+
+	/* TODO: see if PROXYAUTH_AVAIL helps us here */
+	git_cred_free(s->proxy_cred);
+	s->proxy_cred = NULL;
+	giterr_clear();
+	error = opts->credentials(&s->proxy_cred, opts->url, NULL, GIT_CREDTYPE_USERPASS_PLAINTEXT, opts->payload);
+	if (error == GIT_PASSTHROUGH)
+		return error_no_credentials();
+	if (error < 0) {
+		if (!giterr_last())
+			giterr_set(GITERR_NET, "proxy authentication was aborted by the user");
+		return error;
+	}
+
+	if (s->proxy_cred->credtype != GIT_CREDTYPE_USERPASS_PLAINTEXT) {
+		giterr_set(GITERR_NET, "credentials callback returned invalid credential type");
+		return -1;
+	}
+
+	return apply_proxy_creds(s);
+}
+
 static int curls_connect(git_stream *stream)
 {
 	curl_stream *s = (curl_stream *) stream;
-	long sockextr;
-	int failed_cert = 0;
+	long sockextr, connect_last = 0;
+	int failed_cert = 0, error;
+	bool retry_connect;
 	CURLcode res;
-	res = curl_easy_perform(s->handle);
+
+	/* Apply any credentials we've already established */
+	error = apply_proxy_creds(s);
+	if (error < 0 && error != GIT_ENOTFOUND)
+		return seterr_curl(s);
+
+	do {
+		retry_connect = 0;
+		res = curl_easy_perform(s->handle);
+
+		curl_easy_getinfo(s->handle, CURLINFO_HTTP_CONNECTCODE, &connect_last);
+
+		/* HTTP 407 Proxy Authentication Required */
+		if (connect_last == 407) {
+			if ((error = ask_and_apply_proxy_creds(s)) < 0)
+				return error;
+
+			retry_connect = true;
+		}
+	} while (retry_connect);
 
 	if (res != CURLE_OK && res != CURLE_PEER_FAILED_VERIFICATION)
 		return seterr_curl(s);
 	if (res == CURLE_PEER_FAILED_VERIFICATION)
 		failed_cert = 1;
 
-	if ((res = curl_easy_getinfo(s->handle, CURLINFO_LASTSOCKET, &sockextr)) != CURLE_OK)
+	if ((res = curl_easy_getinfo(s->handle, CURLINFO_LASTSOCKET, &sockextr)) != CURLE_OK) {
 		return seterr_curl(s);
+	}
 
 	s->socket = sockextr;
 
@@ -109,6 +183,9 @@ static int curls_set_proxy(git_stream *stream, const git_proxy_options *proxy_op
 	if ((res = curl_easy_setopt(s->handle, CURLOPT_PROXY, s->proxy.url)) != CURLE_OK)
 		return seterr_curl(s);
 
+	if ((res = curl_easy_setopt(s->handle, CURLOPT_PROXYAUTH, CURLAUTH_ANY)) != CURLE_OK)
+		return seterr_curl(s);
+
 	return 0;
 }