allow authentication over STARTTLS (not just SMTPS)

1 files changed, 16 insertions, 2 deletions

diff --git a/qmail-smtpd.c b/qmail-smtpd.c
index 103d4b5..aaf65e8 100644
--- a/qmail-smtpd.c
+++ b/qmail-smtpd.c
@@ -39,6 +39,15 @@ int timeout = 1200;
 
 const char *protocol = "SMTP";
 
+/*
+ There is an inconsistency in the design that we have to work around.
+ When using stunnel to implement SMTPS, the password checker is runtime
+ configurable, since stunnel passes it to us as a cmdline argument.
+ However, STARTTLS has no idea how stunnel is configured (if it exists
+ at all), so we have to use a compiled-in pwchecker.
+ */
+char *pwchecker[] = {"/var/qmail/rbin/checkpassword",  "-", 0};
+
 #ifdef TLS
 #include <sys/stat.h>
 #include "tls.h"
@@ -323,7 +332,7 @@ void smtp_ehlo(arg) char *arg;
     out("250-AUTH LOGIN PLAIN\r\n");
     out("250-AUTH=LOGIN PLAIN\r\n");
 #endif
-  }
+  }  /* else auth not available;  channel lacks privacy */
   out("250-PIPELINING\r\n");
   out("250 8BITMIME\r\n");      /* last one has a space, not a dash */
   seenmail = 0; dohelo(arg);
@@ -683,7 +692,7 @@ char *arg;
 
   if (!hostname || !childargs)
   {
-    out("503 auth not available (#5.3.3)\r\n");
+    out("503 auth not available; channel lacks privacy (#5.3.3)\r\n");
     return;
   }
   if (authd) { err_authd(); return; }
@@ -940,6 +949,11 @@ void tls_init()
     ssl_free(myssl); tls_out("connection failed", err); die_read();
   }
   ssl = myssl;
+/* The following are a kludgey way of indicating that the channel is
+   sufficiently private to allow the sending of passwords:
+ */
+  if (!hostname) hostname = "0";
+  if (!childargs) childargs = pwchecker;
 
   /* populate the protocol string, used in Received */
   if (!stralloc_copys(&proto, "ESMTPS (")