Re: [Exim] create_file = belowhome: unexpected behaviour

Only a little while ago, On Fri, 1 Oct 1999, I wrote:

> On Fri, 1 Oct 1999, Ray Miller wrote:
>
> > But if I specify "save /home/ray/../../tmp/foo" in the filter,
>
> Oh dear. I really don't have a devious enough mind! I will add a check
> to the code to forbid .. components when that check is set. Thanks for
> pointing out the problem.

Here's a patch for Exim 3.03 that fixes this problem. Please don't get
to rely on such fast service. :-)

-- 
Philip Hazel            University of Cambridge Computing Service,
ph10@???      Cambridge, England. Phone: +44 1223 334714.

*** exim-3.03/src/transports/appendfile.c   Mon Aug  2 16:43:08 1999
--- src/transports/appendfile.c     Fri Oct  1 15:49:29 1999
***************
*** 1240,1247 ****
      char *file = filename;
            while (file[0] == '/' && file[1] == '/') file++;
            if (strncmp(file, deliver_home, len) == 0 && file[len] == '/' &&
!             (ob->create_file == create_belowhome ||
!               strchr(file+len+2, '/') == NULL)) OK = TRUE;
            }

          if (!OK)
--- 1373,1381 ----
      char *file = filename;
            while (file[0] == '/' && file[1] == '/') file++;
            if (strncmp(file, deliver_home, len) == 0 && file[len] == '/' &&
!             ((ob->create_file == create_belowhome &&
!              strstr(file+len, "/../") == NULL) ||
!              strchr(file+len+2, '/') == NULL)) OK = TRUE;
            }

          if (!OK)