[Varnish] #896: Strings longer than 256 characters are bad handled in VCL

[Varnish]

#896: Strings longer than 256 characters are bad handled in VCL
-----------------------------------+----------------------------------------
 Reporter:  tmagnien               |        Type:  defect  
   Status:  new                    |    Priority:  normal  
Milestone:                         |   Component:  varnishd
  Version:  trunk                  |    Severity:  normal  
 Keywords:  string regexp vcl 256  |  
-----------------------------------+----------------------------------------
 Hi,

 While trying my 2.1.5 VCL file on a trunk version, I got errors related to
 regexps : Regexp compilation error: missing ).

 I made some tests and found that any regexp longer that 256 characters was
 failing to compile.

 For example, the following line :


 {{{
 if (req.http.host ~ "^(www.abc.fr|www.def.com|...)$") {
 --- do something ---
 }
 }}}


 was failing with a domain list longer than 256 characters.

 After investigation, it seems that the problem is in vcc_decstr function :
 the length of a string is calculated using an unsigned char, which may not
 be enough... This affects all strings in the VCL.

 Here is a simple match proposal :





 {{{
 diff --git a/lib/libvcl/vcc_token.c b/lib/libvcl/vcc_token.c
 index 6818777..56c9672 100644
 --- a/lib/libvcl/vcc_token.c
 +++ b/lib/libvcl/vcc_token.c
 @@ -350,7 +350,7 @@ static int
  vcc_decstr(struct vcc *tl)
  {
         char *q;
 -       unsigned char l;
 +       unsigned int l;

         assert(tl->t->tok == CSTR);
         l = (tl->t->e - tl->t->b) - 2;

 }}}


 Regards,
 Thierry

-- 
Ticket URL: <http://www.varnish-cache.org/trac/ticket/896>
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