tree 7760e53d9e62fcdede9f32234c2eeb00f375359d
parent 9705ba2981016dd6b3b8d690bb8935a396cc0994
author Willy Tarreau <w@1wt.eu> 1477055265 +0200
committer Willy Tarreau <w@1wt.eu> 1477055720 +0200
encoding latin1

MINOR: tcp: make set-src/set-src-port and set-dst/set-dst-port commutative

When the tcp/http actions above were introduced in 1.7-dev4, we used to
proceed like this :

  - set-src/set-dst would force the port to zero
  - set-src-port/set-dst-port would not do anything if the address family is
    neither AF_INET nor AF_INET6.

It was a stupid idea of mine to request this behaviour because it ensures
that these functions cannot be used in a wide number of situations. Because
of the first rule, it is necessary to save the source port one way or
another if only the address has to be changed (so you have to use an
variable). Due to the second rule, there's no way to set the source port
on a unix socket without first overwriting the address. And sometimes it's
really not convenient, especially when there's no way to guarantee that all
fields will properly be set.

In order to fix all this, this small change does the following :
  - set-src/set-dst always preserve the original port even if the address
    family changes. If the previous address family didn't have a port (eg:
    AF_UNIX), then the port is set to zero ;

  - set-src-port/set-dst-port always preserve the original address. If the
    address doesn't have a port, then the family is forced to IPv4 and the
    address to "0.0.0.0".

Thanks to this it now becomes possible to perform one action, the other or
both in any order.