[stunnel-users] stunnel-4.15 doesn't work on Mac OS X 10.4.6

Mon Apr 17 20:49:55 CEST 2006

Thank you.  Here is the patch:
ftp://ftp.mirt.net/stunnel/fdputline.patch

Best regards,
     Mike

On 2006-04-17, at 14:47, SUENAGA Hiroki wrote:

> Dear all,
>
> I found a problem that the stunnel-4.15 doesn't work on
> the Mac OS X 10.4.6. I think this is a BUG.
>
> My environment is:
>
>   - OS: Mac OS X 10.4.6/Intel
>   - Compiler: gcc 4.0.1 (from XCode 2.2)
>   - OpenSSL: 0.9.7i (Mac OS X original version)
>   - Usage: connect to the submission port.
>
> The detail of BUG is the following:
>
> In protocol.c::smtp_client() line 138, fdputline() called with
> argument line = "EHLO localhost." This is a string literal.
>
>   130 static void smtp_client(CLI *c) {
>   ...
>   138     fdputline(c, c->remote_fd.fd, "EHLO localhost");
>   ...
>
> In network.c::fdputline() line 565, the literal is passed to
> 1st argument of safeconcat().
>
>   556 void fdputline(CLI *c, int fd, char *line) {
>   ....
>   565     safeconcat(line, crlf);
>   ...
>
> In common.h line 311, safeconcat() is #define'ed as:
>
>   311 #define safeconcat(dst, src) \
>   312     (dst[STRLEN-1]='\0', strncat((dst), (src), \
>            STRLEN-strlen(dst)-1))
>
> This means the macro safeconcat() write to string literal.
> This is the BUG. In Mac OS X envoronment, string literal is
> NOT writable. So protection fault occurs at this code.
> On the other environment, this breaks somewhere in the heap
> or in the stack. This may also cause a crash.
>
> In stunnel-4.14, fdprintf() is used instead of fdputline().
> fdprint() have own writable buffers on stack, and the string
> literal is copied to the stack. This works fine.
>
> The work around is using own writable buffers in fdputline()
> like fdprint() in stunnel-4.14. But it seems to be a performance
> tuning why fdputline() is used. So I don't know what is the
> correct way to fix this BUG....
>
> I hope this BUG is fixed in the future release.
> If this was already reported,  please ignore this mail.
> Thank you.
>
> Rgards,
>
> ----------
> Internet Initiative Japan Inc.
> Research & Development Section,
> Product Development Division,
> SEIL Business Unit
>
> SUENAGA Hiroki <hsuenaga at iij.ad.jp>
> _______________________________________________
> stunnel-users mailing list
> stunnel-users at mirt.net
> http://stunnel.mirt.net/mailman/listinfo/stunnel-users