Forward/reverse proxy chain losing headers

Question

I have the following setup:
user(browser) -> proxy1 -> proxy2 -> webserver
This has both forward and reverse mappings. In proxy 1, I have an NSAPI plugin that appends a name/value(uid:userid) pair into the HTTP headers, at the end of my current header string . I use
const char *HEADERS = "full-headers"; //HEADER NAME
pblock_findval((char *)HEADERS, request->reqpb))
pblock_remove((char *)HEADERS, request->reqpb);
pblock_nvinsert((char *)HEADERS, (char*)"current list of NV pairs, uid: user123", request->reqpb);
In the previous proxy versions to 3.63, the second proxy and teh webserver receive my entire header string(full-headers) without any issue and just as I sent it.
With version 3.63, my UID is missing from the "
Protocol Request PB (rq->reqpb)" section along with some other info in my header string. I use sdump to view the headers, plus my backend app is not receiving the uid.
Has anyone else had the issue of their headers getting mangled, and or missing in Proxy 3.63 ?Or does anyone have any ideas to the issue?

Answer 1

Yep, good catch
There is a bug in the proxy : Proxy 3.6 SP3 removes "Proxy-authenticate:" HTTP header when forwarding requests to other proxies.
This is basically in adherence to RFC2616 clause
13.5.1 End-to-end and Hop-by-hop Headers:
For the purpose of defining the behavior of caches and non-caching
proxies, we divide HTTP headers into two categories:
- End-to-end headers, which are transmitted to the ultimate
recipient of a request or response. End-to-end headers in
responses MUST be stored as part of a cache entry and MUST be
transmitted in any response formed from a cache entry.
- Hop-by-hop headers, which are meaningful only for a single
transport-level connection, and are not stored by caches or
forwarded by proxies.
The following HTTP/1.1 headers are hop-by-hop headers:
- Connection
- Keep-Alive
- Proxy-Authenticate
- Proxy-Authorization
- TE
- Trailers
- Transfer-Encoding
- Upgrade
All other headers defined by HTTP/1.1 are end-to-end headers.
This somehow messed up the proxy chain configurations
This has been fixed in SP4 which will be released in a week or two
Thx
Maneesh