From: Amos Jeffries <squid3@treenet.co.nz>
Date: Wed, 3 Dec 2014 12:06:59 +0000 (-0800)
Subject: Alternate-Protocol is a hop-by-hop header
X-Git-Tag: SQUID_3_4_10~3
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d8a44dfbd20a87f61bb9dea122d53c30654389ca;p=thirdparty%2Fsquid.git

Alternate-Protocol is a hop-by-hop header

Google are pushing Alternate-Protocol header to arbitrarily move clients
from HTTP to their experimental and proprietary protocols.

When relayed through a proxy this can cause traffic bifurcation with
side effects ranging from client visible failures, to traffic increase
on the network as proxy caching is bypassed, to security vulnerabilities
or privacy information leaks over the experimental protocol.

By treating the Alternate-Protocol header as a hop-by-hop header only
relevant on client->origin connections we can both prevent the above
issues occuring on networks utilizing a proxy, and also participate in
the protocol exprimentation process ourselves.
---

diff --git a/src/HttpHeader.cc b/src/HttpHeader.cc
index 8105063ef4..27c4f8535c 100644
--- a/src/HttpHeader.cc
+++ b/src/HttpHeader.cc
@@ -87,6 +87,7 @@ static const HttpHeaderFieldAttrs HeadersAttrs[] = {
     {"Accept-Ranges", HDR_ACCEPT_RANGES, ftStr},
     {"Age", HDR_AGE, ftInt},
     {"Allow", HDR_ALLOW, ftStr},
+    {"Alternate-Protocol", HDR_ALTERNATE_PROTOCOL, ftStr},
     {"Authorization", HDR_AUTHORIZATION, ftStr},	/* for now */
     {"Cache-Control", HDR_CACHE_CONTROL, ftPCc},
     {"Connection", HDR_CONNECTION, ftStr},
@@ -266,6 +267,7 @@ static http_hdr_type RequestHeadersArr[] = {
 
 static HttpHeaderMask HopByHopHeadersMask;
 static http_hdr_type HopByHopHeadersArr[] = {
+    HDR_ALTERNATE_PROTOCOL,
     HDR_CONNECTION, HDR_HTTP2_SETTINGS, HDR_KEEP_ALIVE, /*HDR_PROXY_AUTHENTICATE,*/ HDR_PROXY_AUTHORIZATION,
     HDR_TE, HDR_TRAILER, HDR_TRANSFER_ENCODING, HDR_UPGRADE, HDR_PROXY_CONNECTION
 };
diff --git a/src/HttpHeader.h b/src/HttpHeader.h
index 8681d1aaca..c86d17cf1d 100644
--- a/src/HttpHeader.h
+++ b/src/HttpHeader.h
@@ -57,6 +57,7 @@ typedef enum {
     HDR_ACCEPT_RANGES,                  /**< RFC 2608, 2616 */
     HDR_AGE,                            /**< RFC 2608, 2616 */
     HDR_ALLOW,                          /**< RFC 2608, 2616 */
+    HDR_ALTERNATE_PROTOCOL,             /**< GFE custom header we may have to erase */
     /*HDR_ALTERNATES,*/                 /* deprecated RFC 2068, 2295 */
     HDR_AUTHORIZATION,                  /**< RFC 2608, 2616, 4559 */
     HDR_CACHE_CONTROL,                  /**< RFC 2608, 2616 */