static const response* check_fqdn(str* s)
{
int at;
int dot;
const char* name;
if ((at = str_findlast(s, '@')) <= 0) {
if ((name = session_getenv("DEFAULTHOST")) != 0) {
at = s->len;
if (!str_catc(s, '@')
|| !str_cats(s, name))
return &resp_oom;
}
else
return &resp_nodomain;
}
if ((dot = str_findlast(s, '.')) < at) {
if ((name = session_getenv("DEFAULTDOMAIN")) != 0) {
if (!str_catc(s, '.')
|| !str_cats(s, name))
return &resp_oom;
}
else
return &resp_nofqdn;
}
return 0;
}
static const response* check_domains(const str* s, const char* domains)
{
unsigned int at;
unsigned int i;
int atend;
if ((at = str_findlast(s, '@')) == (unsigned)-1) {
return &resp_notemptysender;
}
++at;
for (;;) {
/* Skip any leading or doubled colons */
while (*domains == ':')
++domains;
/* Hit end of string without a match */
if (*domains == 0)
return &resp_wrongdomain;
for (atend = 0, i = 0; !atend && at+i < s->len; ++i) {
if (tolower(s->s[at+i]) != tolower(*domains))
break;
++domains;
atend = *domains == ':' || *domains == 0;
}
if (atend && at+i == s->len)
return 0;
/* Skip to next domain in list */
while (*domains != ':' && *domains != 0)
++domains;
}
}
static void copy_addr(const str* addr,
str* saved, str* domain)
{
int at;
str_copy(saved, addr);
str_lower(saved);
if ((at = str_findlast(saved, '@')) != -1)
str_copyb(domain, saved->s + at, saved->len - at);
else
str_truncate(domain, 0);
}
static const response* chkdns_sender(str* sender, str* params)
{
str domstr, dbltxt;
int i;
unsigned char ansbuf[512];
if(sender->len == 0) return 0; /* bounce */
i = str_findlast(sender, '@');
if(i < 0) {
return &resp_badfrom; /* no domain */
}
str_init(&domstr);
str_copyb(&domstr, sender->s+i+1, sender->len-i-1);
if(domstr.len == 0) { /* null domain */
str_free(&domstr);
return &resp_badfrom;
}
/* first check dbl */
if(dblchk(&domstr, &dbltxt)) {
session_setenv("RBLSMTPD", dbltxt.s, 0);
session_setnum("dblfrom", 1);
session_setnum("sump", 1);
msg2("MAIL FROM in DBL ",dbltxt.s);
str_free(&domstr);
if(getenv("DBLREJECT")) {
resp_baddbl.message = dbltxt.s;
return &resp_baddbl;
}
return 0;
}
i = res_query(domstr.s, C_IN, T_MX, ansbuf, sizeof(ansbuf));
if(i > 0 && ((HEADER *)ansbuf)->ancount != 0) { /* has an MX */
str_free(&domstr);
return 0;
}
i = res_query(domstr.s, C_IN, T_A, ansbuf, sizeof(ansbuf));
if(i > 0 && ((HEADER *)ansbuf)->ancount != 0) { /* has an A */
str_free(&domstr);
return 0;
}
i = res_query(domstr.s, C_IN, T_AAAA, ansbuf, sizeof(ansbuf));
str_free(&domstr);
if(i > 0 && ((HEADER *)ansbuf)->ancount != 0) return 0; /* has an AAAA */
return &resp_badfrom;
(void)params;
}
