Re: PF_NETLINK support in glibc

[Philip Blundell <philb@gnu.org>]

>The glibc CVS tree doesn't seem to have support for the new PF_NETLINK  
>& rtnetlink socket family in Linux 2.1. Unfortunately the linux/* include
>file conflicts partly with glibc.

Here's a patch I cooked up to add support for netlink sockets.  Can you (and
anybody else who's interested) take a look and let me know if it seems OK.
  
I don't have any applications here that use AF_NETLINK so I haven't tested 
it myself.

p.

1998-11-12  Philip Blundell  <philb@gnu.org>

	* sysdeps/unix/sysv/linux/netlink/netlink.h: New file, support for 
	Linux AF_NETLINK sockets (needed since the kernel version is
	unusable).
	* sysdeps/unix/sysv/linux/Makefile: Install it.
	* sysdeps/unix/sysv/linux/Dist: Distribute it.

--- libc/sysdeps/unix/sysv/linux/Makefile~	Thu Oct 29 03:07:00 1998
+++ libc/sysdeps/unix/sysv/linux/Makefile	Thu Nov 12 19:18:52 1998
@@ -84,7 +84,7 @@
 		  netinet/if_fddi.h netinet/if_tr.h netinet/igmp.h \
 		  netipx/ipx.h netash/ash.h netax25/ax25.h netatalk/at.h \
 		  netrom/netrom.h netpacket/packet.h netrose/rose.h \
-		  neteconet/ec.h
+		  neteconet/ec.h netlink/netlink.h
 endif
 
 # Don't compile the ctype glue code, since there is no old non-GNU C library.
--- libc/sysdeps/unix/sysv/linux/Dist~	Thu Oct 29 03:07:00 1998
+++ libc/sysdeps/unix/sysv/linux/Dist	Thu Nov 12 19:18:47 1998
@@ -35,6 +35,7 @@
 netinet/igmp.h
 netinet/in_systm.h
 netinet/ip_fw.h
+netlink/netlink.h
 netpacket/packet.h
 netipx/ipx.h
 netrom/netrom.h
--- /dev/null	Sun Oct 12 19:38:15 1997
+++ libc/sysdeps/unix/sysv/linux/netlink/netlink.h	Thu Nov 12 19:17:20 1998
@@ -0,0 +1,125 @@
+/* Definitions for use with Linux AF_NETLINK sockets.
+   Copyright (C) 1998 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#ifndef __NETLINK_NETLINK_H
+#define __NETLINK_NETLINK_H	1
+
+#include <features.h>
+
+#include <sys/types.h>
+#include <bits/sockaddr.h>
+
+__BEGIN_DECLS
+
+struct sockaddr_nl
+  {
+    __SOCKADDR_COMMON (nl_);
+    unsigned short nl_pad;		/* zero.  */
+    uint32_t nl_pid;			/* process pid.  */
+    uint32_t nl_groups;			/* multicast groups mask.  */
+  };
+
+#define NETLINK_ROUTE		0	/* Routing/device hook.  */
+#define NETLINK_SKIP		1	/* Reserved for ENskip.  */
+#define NETLINK_USERSOCK	2	/* Reserved for user mode 
+					   socket protocolss.  */
+#define NETLINK_FIREWALL	3	/* Firewalling hook.  */
+#define NETLINK_ARPD		8
+#define NETLINK_ROUTE6		11	/* AF_INET6 route comm channel */
+#define NETLINK_IP6_FW		13
+#define NETLINK_TAPBASE		16	/* 16 to 31 are ethertap */
+
+#define MAX_LINKS 32		
+
+struct nlmsghdr
+  {
+    uint32_t nlmsg_len;		/* Length of message including header */
+    uint16_t nlmsg_type;	/* Message content */
+    uint16_t nlmsg_flags;	/* Additional flags */
+    uint32_t nlmsg_seq;		/* Sequence number */
+    uint32_t nlmsg_pid;		/* Sending process PID */
+  };
+
+/* Flag bits */
+#define NLM_F_REQUEST	1	/* Message is a request.  */
+#define NLM_F_MULTI	2	/* Multipart message, terminated by 
+				   NLMSG_DONE.  */
+#define NLM_F_ACK	4	/* If operation succeeds, reply with ack.  */
+#define NLM_F_ECHO	8	/* Echo this request.  */
+
+/* Modifiers to GET request */
+#define NLM_F_ROOT	0x100	/* specify tree	root.  */
+#define NLM_F_MATCH	0x200	/* return all matching.  */
+#define NLM_F_ATOMIC	0x400	/* atomic GET.  */
+#define NLM_F_DUMP	(NLM_F_ROOT|NLM_F_MATCH)
+
+/* Modifiers to NEW request */
+#define NLM_F_REPLACE	0x100	/* Override existing.  */
+#define NLM_F_EXCL	0x200	/* Do not touch, if it exists.  */
+#define NLM_F_CREATE	0x400	/* Create, if it does not exist.  */
+#define NLM_F_APPEND	0x800	/* Add to end of list.  */
+
+/*
+   4.4BSD ADD		NLM_F_CREATE|NLM_F_EXCL
+   4.4BSD CHANGE	NLM_F_REPLACE
+
+   True CHANGE		NLM_F_CREATE|NLM_F_REPLACE
+   Append		NLM_F_CREATE
+   Check		NLM_F_EXCL
+ */
+
+#define NLMSG_ALIGNTO	4
+
+#define NLMSG_ALIGN(len)		\
+	(((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
+
+#define NLMSG_LENGTH(len)		\
+	((len)+NLMSG_ALIGN(sizeof(struct nlmsghdr)))
+
+#define NLMSG_SPACE(len)		\
+	NLMSG_ALIGN(NLMSG_LENGTH(len))
+
+#define NLMSG_DATA(nlh)			\
+	((void*)(((char*)nlh) + NLMSG_LENGTH(0)))
+
+#define NLMSG_NEXT(nlh,len)		\
+	 ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \
+	  (struct nlmsghdr*)(((char*)(nlh)) + NLMSG_ALIGN((nlh)->nlmsg_len)))
+
+#define NLMSG_OK(nlh,len)		\
+	((len) > 0 && (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) 
+		&& (nlh)->nlmsg_len <= (len))
+
+#define NLMSG_PAYLOAD(nlh,len)		\
+	((nlh)->nlmsg_len - NLMSG_SPACE((len)))
+
+#define NLMSG_NOOP		0x1	/* Nothing.  */
+#define NLMSG_ERROR		0x2	/* Error.  */
+#define NLMSG_DONE		0x3	/* End of a dump.  */
+#define NLMSG_OVERRUN		0x4	/* Data lost.  */
+
+struct nlmsgerr
+  {
+    int	error;
+    struct nlmsghdr msg;
+  };
+
+#define NET_MAJOR 36		/* Major 36 is reserved for networking 						*/
+
+#endif