I get the same result in 2.2.x and 2.4.x. I don't think HttpProtocolOptions was meant to revert every strict processing change.

Hi Eric,

can you clarify, what the same result means?

Do you get the same results as I did:
apache 2.4.x works and apache 2.2.x does not?

Or did apache 2.4.25 and 2.2.32 behave the same and work / do not work both?

Michael

(In reply to Michael from comment #2)
> Hi Eric,
> 
> can you clarify, what the same result means?
> 
> Do you get the same results as I did:
> apache 2.4.x works and apache 2.2.x does not?
> 
> Or did apache 2.4.25 and 2.2.32 behave the same and work / do not work both?
> 

sorry, both rejected the underscore and HTTPProtocolOptions didn't change either behavior.

I tested again on two different servers, same result again:

Apache 2.2.32 and 2.4.25 both configured with on vHost which has a ServerAlias bad_request_hostname and HttpProtocolOptions Unsafe LenientMethods Allow0.9 in server (not vHost!) context.

curl -v -H "Host: bad_request_hostname" http://127.0.0.1/

Apache 2.2.32: HTTP/1.1 400 Bad Request

Apache 2.4.25: HTTP/1.1 200 OK

I'm a little confused ..

Michael

Today I faced another issue, that's confusing me even more. Testcase is apache 2.4.25, HttpProtocolOptions set to "Unsafe LenientMethods Allow0.9".

1) curl -H "Host: my_invalid_hostname" -v http://localhost/
   Returns: HTTP/1.1 200 OK
   OK - Unsafe mode allows a Host header containing a underline.

2) curl -H "Accept<TAB>: application/xml" -v http://localhost/
   Returns: HTTP/1.1 400 Bad Request
   Debug output: Request header field name is malformed: Accept\t: application/xml

Looking into the sourcecode (server/protocol.c, line 1130) the message "Request header field name is malformed" only will be logged in strict mode, but not in unsafe mode ..

Best regards,
Michael

I have the same behaviour. Even with 
HttpProtocolOptions  Unsafe LenientMethods Allow0.9

requests may still be blocked, and I have the following log-entry:

[Thu Mar 09 11:02:51 2017] [debug] protocol.c(828): [client 10.0.209.5] HTTP Request Line; Excess whitespace (disallowed by HttpProtocolOptions Strict


I compared the code with httpd/2.4.25 (where the request is not blocked), and the functions merge_core_server_configs (core.c) do slightly differ:

in 2.2.32:
static void *merge_core_server_configs(apr_pool_t *p, void *basev, void *virtv)
{
    core_server_config *base = (core_server_config *)basev;
    core_server_config *virt = (core_server_config *)virtv;
    core_server_config *conf;

    conf = (core_server_config *)apr_pmemdup(p, base, sizeof(core_server_config));

in 2.4.25:
static void *merge_core_server_configs(apr_pool_t *p, void *basev, void *virtv)
{
    core_server_config *base = (core_server_config *)basev;
    core_server_config *virt = (core_server_config *)virtv;
    core_server_config *conf = (core_server_config *)
                               apr_pmemdup(p, base, sizeof(core_server_config));

As you can see, in 2.4.25 the 'conf' is taken from 'base' and not from 'virtv' like in 2.2.32.
I changed the code in 2.2.32. and then the request is not blocked any more.
I have no idea if this is the right solution, because of the other parameters that are used.

In the above snippets I see conf being copied from base in both cases...

(In reply to Jim Jagielski from comment #7)
> In the above snippets I see conf being copied from base in both cases...
This is already fixed in 2.2.x HEAD

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