Raise smtp_cmd_buffer_size to 16384.

Needed to interoperate with SASL commands containing a large
initial-response; in practice, GSSAPI with authorisation data, such as
in a Windows domain.

Patch from Paul Fisher.

fixes bug 879

diff --git a/doc/doc-txt/ChangeLog b/doc/doc-txt/ChangeLog
index 2db30fed7af8de2b1aa07b5e694c46373be538c3..0441c326e56330a4fe81a75932e4c40a83e6fc48 100644 (file)
--- a/doc/doc-txt/ChangeLog
+++ b/doc/doc-txt/ChangeLog
@@ -88,6 +88,9 @@ TF/06 Removed a few PCRE remnants.
 TF/07 Automatically extract Exim's version number from tags in the git
       repository when doing development or release builds.
 
+PP/02 Raise smtp_cmd_buffer_size to 16kB. Patch from Paul Fisher.
+      Bugzilla 879.
+
 
 Exim version 4.76
 -----------------

diff --git a/src/src/smtp_in.c b/src/src/smtp_in.c
index f1c7aec3451f825de2db8d32d2fd37310e4fbc40..7ca56e25527cb2747cedfd6a35b3596c6b533e00 100644 (file)
--- a/src/src/smtp_in.c
+++ b/src/src/smtp_in.c
@@ -36,9 +36,14 @@ uschar *tcp_wrappers_name;
 /* Size of buffer for reading SMTP commands. We used to use 512, as defined
 by RFC 821. However, RFC 1869 specifies that this must be increased for SMTP
 commands that accept arguments, and this in particular applies to AUTH, where
-the data can be quite long. */
+the data can be quite long.  More recently this value was 2048 in Exim; 
+however, RFC 4954 (circa 2007) recommends 12288 bytes to handle AUTH.  Clients
+such as Thunderbird will send an AUTH with an initial-response for GSSAPI. 
+The maximum size of a Kerberos ticket under Windows 2003 is 12000 bytes, and 
+we need room to handle large base64-encoded AUTHs for GSSAPI.
+*/
 
-#define smtp_cmd_buffer_size  2048
+#define smtp_cmd_buffer_size  16384
 
 /* Size of buffer for reading SMTP incoming packets */