[stunnel-users] Duplicate 220 in protocol.c, smtp_server

Hans Werner Strube strube at physik3.gwdg.de
Fri Sep 1 11:03:27 CEST 2006

At least since stunnel 4.15 - but not yet in 4.09 (don't know about the
intermediate versions) - there is a (cosmetic only?) bug in the "welcome"
forwarding of the smtp_server in protocol.c (lines 177-187 in 4.16):
    fdgetline(c, c->remote_fd.fd, line); 
    if(!isprefix(line, "220")) {
        s_log(LOG_ERR, "Unknown server welcome");
        longjmp(c->err, 1);
    fdprintf(c, c->local_wfd.fd, "220%s + stunnel", line);
    fdgetline(c, c->local_rfd.fd, line); 
    if(!isprefix(line, "EHLO ")) {
        s_log(LOG_ERR, "Unknown client EHLO");
        longjmp(c->err, 1);
Although the line read from remote_fd.fd already starts with "220", another
220 is prepended in forwarding to local_wfd.fd, line 182. This seems to haveno adverse effects, but this line should better be changed to:
    fdprintf(c, c->local_wfd.fd, "%s + stunnel", line);

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