ref: e4af9bc39296b6e1080e905151aa8f981770e49e
parent: 4908ea43d7603c435038de6739dd4589585b071b
author: cinap_lenrek <cinap_lenrek@felloff.net>
date: Sat Nov 8 04:00:04 EST 2014
smtpd: cleanup hello() domain check code theres no point in doing domain checks on literal ip addresses, so handle that case early.
--- a/sys/src/cmd/upas/smtp/smtpd.c
+++ b/sys/src/cmd/upas/smtp/smtpd.c
@@ -335,6 +335,7 @@
{char **mynames;
char *ldot, *rdot;
+ char *p;
him = s_to_c(himp);
syslog(0, "smtpd", "%s from %s as %s", extended? "ehlo": "helo",
@@ -342,89 +343,81 @@
if(rejectcheck())
return;
- if (strchr(him, '.') && nci && !trusted && fflag &&
- strcmp(nci->rsys, nci->lsys) != 0){+ if (him[0] == '[') {/*
- * We don't care if he lies about who he is, but it is
- * not okay to pretend to be us. Many viruses do this,
- * just parroting back what we say in the greeting.
+ * reject literal ip addresses when not trusted.
*/
- if(strcmp(him, dom) == 0)
+ if (!trusted)
goto Liarliar;
- for(mynames = sysnames_read(); mynames && *mynames; mynames++){- if(cistrcmp(*mynames, him) == 0){-Liarliar:
- syslog(0, "smtpd",
- "Hung up on %s; claimed to be %s",
- nci->rsys, him);
- if(Dflag)
- sleep(delaysecs()*1000);
- reply("554 5.7.0 Liar!\r\n");- exits("client pretended to be us");- return;
- }
+ him = nci->rsys;
+ } else {+ if (!trusted && fflag && nci && strcmp(nci->rsys, nci->lsys) != 0){+ /*
+ * We don't care if he lies about who he is, but it is
+ * not okay to pretend to be us. Many viruses do this,
+ * just parroting back what we say in the greeting.
+ */
+ if(cistrcmp(him, dom) == 0)
+ goto Liarliar;
+ for(mynames = sysnames_read(); mynames && *mynames; mynames++)
+ if(cistrcmp(*mynames, him) == 0)
+ goto Liarliar;
}
- }
- /*
- * it is unacceptable to claim any string that doesn't look like
- * a domain name (e.g., has at least one dot in it), but
- * Microsoft mail client software gets this wrong, so let trusted
- * (local) clients omit the dot.
- */
- rdot = strrchr(him, '.');
- if (rdot && rdot[1] == '\0') {- *rdot = '\0'; /* clobber trailing dot */
- rdot = strrchr(him, '.'); /* try again */
- }
- if (!trusted && rdot == nil)
- goto Liarliar;
- /*
- * Reject obviously bogus domains and those reserved by RFC 2606.
- */
- if (rdot == nil)
- rdot = him;
- else
- rdot++;
- if (cistrcmp(rdot, "localdomain") == 0 ||
- cistrcmp(rdot, "localhost") == 0 ||
- cistrcmp(rdot, "example") == 0 ||
- cistrcmp(rdot, "invalid") == 0 ||
- cistrcmp(rdot, "test") == 0)
- goto Liarliar; /* bad top-level domain */
- /* check second-level RFC 2606 domains: example\.(com|net|org) */
- if (rdot != him)
- *--rdot = '\0';
- ldot = strrchr(him, '.');
- if (rdot != him)
- *rdot = '.';
- if (ldot == nil)
- ldot = him;
- else
- ldot++;
- if (cistrcmp(ldot, "example.com") == 0 ||
- cistrcmp(ldot, "example.net") == 0 ||
- cistrcmp(ldot, "example.org") == 0)
- goto Liarliar;
-
- /*
- * similarly, if the claimed domain is not an address-literal,
- * require at least one letter, which there will be in
- * at least the last component (e.g., .com, .net) if it's real.
- * this rejects non-address-literal IP addresses,
- * among other bogosities.
- */
- if (!trusted && him[0] != '[') {- char *p;
-
+ /*
+ * require at least one letter, which there will be in
+ * at least the last component (e.g., .com, .net) if it's real.
+ * this rejects non-address-literal IP addresses,
+ * among other bogosities.
+ */
for (p = him; *p != '\0'; p++)
if (isascii(*p) && isalpha(*p))
break;
if (*p == '\0')
goto Liarliar;
+
+ /*
+ * it is unacceptable to claim any string that doesn't look like
+ * a domain name (e.g., has at least one dot in it), but
+ * Microsoft mail client software gets this wrong, so let trusted
+ * (local) clients omit the dot.
+ */
+ rdot = strrchr(him, '.');
+ if (rdot && rdot[1] == '\0') {+ *rdot = '\0'; /* clobber trailing dot */
+ rdot = strrchr(him, '.'); /* try again */
+ }
+ if (!trusted && rdot == nil)
+ goto Liarliar;
+
+ /*
+ * Reject obviously bogus domains and those reserved by RFC 2606.
+ */
+ if (rdot == nil)
+ rdot = him;
+ else
+ rdot++;
+ if (cistrcmp(rdot, "localdomain") == 0 ||
+ cistrcmp(rdot, "localhost") == 0 ||
+ cistrcmp(rdot, "example") == 0 ||
+ cistrcmp(rdot, "invalid") == 0 ||
+ cistrcmp(rdot, "test") == 0)
+ goto Liarliar; /* bad top-level domain */
+ /* check second-level RFC 2606 domains: example\.(com|net|org) */
+ if (rdot != him)
+ *--rdot = '\0';
+ ldot = strrchr(him, '.');
+ if (rdot != him)
+ *rdot = '.';
+ if (ldot == nil)
+ ldot = him;
+ else
+ ldot++;
+ if (cistrcmp(ldot, "example.com") == 0 ||
+ cistrcmp(ldot, "example.net") == 0 ||
+ cistrcmp(ldot, "example.org") == 0)
+ goto Liarliar;
}
- if(strchr(him, '.') == 0 && nci != nil && strchr(nci->rsys, '.') != nil)
- him = nci->rsys;
if(Dflag)
sleep(delaysecs()*1000);
@@ -438,6 +431,15 @@
else
reply("250 AUTH CRAM-MD5\r\n");}
+ return;
+
+Liarliar:
+ syslog(0, "smtpd", "Hung up on %s; claimed to be %s",
+ nci->rsys, him);
+ if(Dflag)
+ sleep(delaysecs()*1000);
+ reply("554 5.7.0 Liar!\r\n");+ exits("client pretended to be us");}
void