From e3826f1e946e7d2354943232f1457be1455a29e2 Mon Sep 17 00:00:00 2001 From: Amerigo Wang Date: Wed, 5 May 2010 00:27:06 +0000 Subject: net: reserve ports for applications using fixed port numbers (Dropped the infiniband part, because Tetsuo modified the related code, I will send a separate patch for it once this is accepted.) This patch introduces /proc/sys/net/ipv4/ip_local_reserved_ports which allows users to reserve ports for third-party applications. The reserved ports will not be used by automatic port assignments (e.g. when calling connect() or bind() with port number 0). Explicit port allocation behavior is unchanged. Signed-off-by: Octavian Purdila Signed-off-by: WANG Cong Cc: Neil Horman Cc: Eric Dumazet Cc: Eric W. Biederman Signed-off-by: David S. Miller --- Documentation/networking/ip-sysctl.txt | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) (limited to 'Documentation/networking') diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 8b72c88ba213..d0536b5a4e01 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -588,6 +588,37 @@ ip_local_port_range - 2 INTEGERS (i.e. by default) range 1024-4999 is enough to issue up to 2000 connections per second to systems supporting timestamps. +ip_local_reserved_ports - list of comma separated ranges + Specify the ports which are reserved for known third-party + applications. These ports will not be used by automatic port + assignments (e.g. when calling connect() or bind() with port + number 0). Explicit port allocation behavior is unchanged. + + The format used for both input and output is a comma separated + list of ranges (e.g. "1,2-4,10-10" for ports 1, 2, 3, 4 and + 10). Writing to the file will clear all previously reserved + ports and update the current list with the one given in the + input. + + Note that ip_local_port_range and ip_local_reserved_ports + settings are independent and both are considered by the kernel + when determining which ports are available for automatic port + assignments. + + You can reserve ports which are not in the current + ip_local_port_range, e.g.: + + $ cat /proc/sys/net/ipv4/ip_local_port_range + 32000 61000 + $ cat /proc/sys/net/ipv4/ip_local_reserved_ports + 8080,9148 + + although this is redundant. However such a setting is useful + if later the port range is changed to a value that will + include the reserved ports. + + Default: Empty + ip_nonlocal_bind - BOOLEAN If set, allows processes to bind() to non-local IP addresses, which can be quite useful - but may break some applications. -- cgit v1.2.3