[asterisk-dev] [Code Review] SIP URI comparison test (plus some bug fixes)

[Olle E. Johansson]

21 jul 2010 kl. 16.56 skrev Rod Dorman:

> On Wednesday, July 21, 2010, 04:18:43, Kevin P. Fleming wrote:
>> On 07/21/2010 10:00 AM, Olle E. Johansson wrote:
>>> 20 jul 2010 kl. 15.15 skrev Simon Perreault:
>>>> /trunk/channels/sip/reqresp_parser.c
>>>> <https://reviewboard.asterisk.org/r/792/#comment5354>
>>>> 
>>>>   There's a subtle but important bug here: glibc's strcasecmp() is locale-dependent. SIP URI domains are limited to the ASCII character set. So we want ASCII-based case-insensitive comparison, not something that depends on the current locale.
>>>> 
>>>>   This could be solved by using strcasecmp_l() and passing the "C" locale (I think). Or just roll your own ASCII-based strcasecmp().
>>> 
>>> That is a huge issue and possibly affects many different parts of asterisk.
>>> 
>>> While writing the bug report I forgot to mention that the string comparision of IP also affects IPv4.
>>> 
>>> 192.02.68.01 == 192.02.68.1
>>> 192.2.068.1 != 192.2.68.1
>>> 
>>> The zero prefix indicates that the group is written in octal notation...
> 
>> Are you sure about that? The ABNF that Mark already posted shows that
>> each group is limited to three digits, and three digits is not adequate
>> to allow for the range 0-255 to be expressed on octal, only in decimal.
> 
> Not only that, in RFC 3986 "Uniform Resource Identifier (URI): Generic
> Syntax" under section "7.4 Rare IP Address Formats" it explicitly states
>    These additional IP address formats are not allowed in the URI
>    syntax due to differences between platform implementations.
> 

Right. That's the theory. Then you have what happens out there in the wild... 

The new draft points out in very detail that you should compare the ip address in binary. Period.

/O