From 545ff7783cebddc2ca5b2af67a6f13b1a01a4d03 Mon Sep 17 00:00:00 2001
From: Anders Svensson <anders@erlang.org>
Date: Wed, 25 Mar 2015 07:21:46 +0100
Subject: Add service_opt() incoming_maxlen

To bound the length of incoming messages that will be decoded. A message
longer than the specified number of bytes is discarded. An
incoming_maxlen_exceeded counter is incremented to make note of the
occurrence.

The motivation is to prevent a sufficiently malicious peer from
generating significant load by sending long messages with many AVPs for
diameter to decode. The 24-bit message length header accomodates

  (16#FFFFFF - 20) div 12 = 1398099

Unsigned32 AVPs for example, which the current record-valued decode is
too slow with in practice. A bound of 16#FFFF bytes allows for 5461
small AVPs, which is probably more than enough for the majority of
applications, but the default is the full 16#FFFFFF.
---
 lib/diameter/doc/src/diameter.xml | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

(limited to 'lib/diameter/doc/src')

diff --git a/lib/diameter/doc/src/diameter.xml b/lib/diameter/doc/src/diameter.xml
index 37e67d8630..6e41b01c44 100644
--- a/lib/diameter/doc/src/diameter.xml
+++ b/lib/diameter/doc/src/diameter.xml
@@ -783,6 +783,27 @@ be matched by corresponding &capability; configuration, of
 
 </item>
 
+<marker id="incoming_maxlen"/>
+<tag><c>{incoming_maxlen, 0..16777215}</c></tag>
+<item>
+<p>
+Bound on the expected size of incoming Diameter messages.
+Messages larger than the specified number of bytes are discarded.</p>
+
+<p>
+Defaults to <c>16777215</c>, the maximum value of the 24-bit Message
+Length field in a Diameter Header.</p>
+
+<warning>
+<p>
+This option should be set to as low a value as is sufficient for the
+Diameter applications and peers in question, since decoding incoming
+messages from a malicious peer can otherwise generate significant
+load.</p>
+</warning>
+
+</item>
+
 <tag><c>{restrict_connections, false
                              | node
                              | nodes
-- 
cgit v1.2.3


From 7edb0dd681b09df8865855eda1150e4a92b54a0a Mon Sep 17 00:00:00 2001
From: Anders Svensson <anders@erlang.org>
Date: Thu, 26 Mar 2015 12:52:04 +0100
Subject: Limit FQDN in DiameterURI to 255 octets

As for the port number in the parent commit, a FQDN can't be arbitrarily
long, at most 255 octets. Make decode fail if it's more.
---
 lib/diameter/doc/src/diameter_dict.xml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'lib/diameter/doc/src')

diff --git a/lib/diameter/doc/src/diameter_dict.xml b/lib/diameter/doc/src/diameter_dict.xml
index 9db9bcffde..5cf1b174a0 100644
--- a/lib/diameter/doc/src/diameter_dict.xml
+++ b/lib/diameter/doc/src/diameter_dict.xml
@@ -529,7 +529,7 @@ answer record and passed to a &app_handle_request;
 callback upon reception of an incoming request.</p>
 
 <p>
-In cases in which there is a choice between list() and binary() types
+In cases in which there is a choice between string() and binary() types
 for OctetString() and derived types, the representation is determined
 by the value of &mod_string_decode;.</p>
 
-- 
cgit v1.2.3