libmnl: other OS support

libmnl: other OS support

[Jan Engelhardt]

The following changes since commit 30923494424b604b1d59087e06fccf0637c0c2c5:

  doxygen: exclude EXPORT_SYMBOL and skip .git files (2011-02-08 15:19:19 +0100)

are available in the git repository at:
  git://dev.medozas.de/libmnl master

Jan Engelhardt (3):
      src: use limits.h header
      include: use sanitized header from headers_install
      build: support compilation on non-Linuxes

 configure.ac                    |   13 ++--
 include/generic/linux/netlink.h |  152 +++++++++++++++++++++++++++++++++++++++
 include/linux/netlink.h         |  128 +--------------------------------
 src/attr.c                      |    3 +-
 4 files changed, 162 insertions(+), 134 deletions(-)
 create mode 100644 include/generic/linux/netlink.h

[PATCH 1/3] src: use limits.h header

[Jan Engelhardt]

values.h is not present on other systems, and the glibc copy reads
right away: Old compatibility names for <limits.h> and <float.h>
constants.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
---
 src/attr.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/src/attr.c b/src/attr.c
index c0ba938..55a80d6 100644
--- a/src/attr.c
+++ b/src/attr.c
@@ -6,10 +6,9 @@
  * by the Free Software Foundation; either version 2.1 of the License, or
  * (at your option) any later version.
  */
-
+#include <limits.h>	/* for INT_MAX */
 #include <libmnl/libmnl.h>
 #include <string.h>
-#include <values.h>	/* for INT_MAX */
 #include <errno.h>
 #include "internal.h"
 
-- 
1.7.1

[PATCH 2/3] include: use sanitized header from headers_install

[Jan Engelhardt]

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
---
 include/linux/netlink.h |  128 +----------------------------------------------
 1 files changed, 1 insertions(+), 127 deletions(-)

diff --git a/include/linux/netlink.h b/include/linux/netlink.h
index 1235669..f55ed8c 100644
--- a/include/linux/netlink.h
+++ b/include/linux/netlink.h
@@ -70,7 +70,7 @@ struct nlmsghdr {
    Check		NLM_F_EXCL
  */
 
-#define NLMSG_ALIGNTO	4
+#define NLMSG_ALIGNTO	4U
 #define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
 #define NLMSG_HDRLEN	 ((int) NLMSG_ALIGN(sizeof(struct nlmsghdr)))
 #define NLMSG_LENGTH(len) ((len)+NLMSG_ALIGN(NLMSG_HDRLEN))
@@ -144,131 +144,5 @@ struct nlattr {
 #define NLA_ALIGN(len)		(((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1))
 #define NLA_HDRLEN		((int) NLA_ALIGN(sizeof(struct nlattr)))
 
-#ifdef __KERNEL__
-
-#include <linux/capability.h>
-#include <linux/skbuff.h>
-
-struct net;
-
-static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb)
-{
-	return (struct nlmsghdr *)skb->data;
-}
-
-struct netlink_skb_parms {
-	struct ucred		creds;		/* Skb credentials	*/
-	__u32			pid;
-	__u32			dst_group;
-	kernel_cap_t		eff_cap;
-	__u32			loginuid;	/* Login (audit) uid */
-	__u32			sessionid;	/* Session id (audit) */
-	__u32			sid;		/* SELinux security id */
-};
-
-#define NETLINK_CB(skb)		(*(struct netlink_skb_parms*)&((skb)->cb))
-#define NETLINK_CREDS(skb)	(&NETLINK_CB((skb)).creds)
-
-
-extern void netlink_table_grab(void);
-extern void netlink_table_ungrab(void);
-
-extern struct sock *netlink_kernel_create(struct net *net,
-					  int unit,unsigned int groups,
-					  void (*input)(struct sk_buff *skb),
-					  struct mutex *cb_mutex,
-					  struct module *module);
-extern void netlink_kernel_release(struct sock *sk);
-extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
-extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
-extern void __netlink_clear_multicast_users(struct sock *sk, unsigned int group);
-extern void netlink_clear_multicast_users(struct sock *sk, unsigned int group);
-extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
-extern int netlink_has_listeners(struct sock *sk, unsigned int group);
-extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock);
-extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 pid,
-			     __u32 group, gfp_t allocation);
-extern int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb,
-	__u32 pid, __u32 group, gfp_t allocation,
-	int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data),
-	void *filter_data);
-extern int netlink_set_err(struct sock *ssk, __u32 pid, __u32 group, int code);
-extern int netlink_register_notifier(struct notifier_block *nb);
-extern int netlink_unregister_notifier(struct notifier_block *nb);
-
-/* finegrained unicast helpers: */
-struct sock *netlink_getsockbyfilp(struct file *filp);
-int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
-		      long *timeo, struct sock *ssk);
-void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
-int netlink_sendskb(struct sock *sk, struct sk_buff *skb);
-
-/*
- *	skb should fit one page. This choice is good for headerless malloc.
- *	But we should limit to 8K so that userspace does not have to
- *	use enormous buffer sizes on recvmsg() calls just to avoid
- *	MSG_TRUNC when PAGE_SIZE is very large.
- */
-#if PAGE_SIZE < 8192UL
-#define NLMSG_GOODSIZE	SKB_WITH_OVERHEAD(PAGE_SIZE)
-#else
-#define NLMSG_GOODSIZE	SKB_WITH_OVERHEAD(8192UL)
-#endif
-
-#define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN)
-
-
-struct netlink_callback {
-	struct sk_buff		*skb;
-	const struct nlmsghdr	*nlh;
-	int			(*dump)(struct sk_buff * skb,
-					struct netlink_callback *cb);
-	int			(*done)(struct netlink_callback *cb);
-	int			family;
-	long			args[6];
-};
-
-struct netlink_notify {
-	struct net *net;
-	int pid;
-	int protocol;
-};
-
-static __inline__ struct nlmsghdr *
-__nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags)
-{
-	struct nlmsghdr *nlh;
-	int size = NLMSG_LENGTH(len);
-
-	nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size));
-	nlh->nlmsg_type = type;
-	nlh->nlmsg_len = size;
-	nlh->nlmsg_flags = flags;
-	nlh->nlmsg_pid = pid;
-	nlh->nlmsg_seq = seq;
-	if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0)
-		memset(NLMSG_DATA(nlh) + len, 0, NLMSG_ALIGN(size) - size);
-	return nlh;
-}
-
-#define NLMSG_NEW(skb, pid, seq, type, len, flags) \
-({	if (unlikely(skb_tailroom(skb) < (int)NLMSG_SPACE(len))) \
-		goto nlmsg_failure; \
-	__nlmsg_put(skb, pid, seq, type, len, flags); })
-
-#define NLMSG_PUT(skb, pid, seq, type, len) \
-	NLMSG_NEW(skb, pid, seq, type, len, 0)
-
-extern int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
-			      const struct nlmsghdr *nlh,
-			      int (*dump)(struct sk_buff *skb, struct netlink_callback*),
-			      int (*done)(struct netlink_callback*));
-
-
-#define NL_NONROOT_RECV 0x1
-#define NL_NONROOT_SEND 0x2
-extern void netlink_set_nonroot(int protocol, unsigned flag);
-
-#endif /* __KERNEL__ */
 
 #endif	/* __LINUX_NETLINK_H */
-- 
1.7.1

[PATCH 3/3] build: support compilation on non-Linuxes

[Jan Engelhardt]

Netlink is a usable TLV protocol for IPC (e.g. over AF_LOCAL sockets)
in itself even if other operating systems do not have kernel support
for it.
This tested on FreeBSD 8.2.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
---
 configure.ac                    |   13 ++--
 include/generic/linux/netlink.h |  152 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 160 insertions(+), 5 deletions(-)
 create mode 100644 include/generic/linux/netlink.h

diff --git a/configure.ac b/configure.ac
index a9fde6c..6b351a0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -12,15 +12,18 @@ AC_EXEEXT
 AC_DISABLE_STATIC
 LT_INIT
 CHECK_GCC_FVISIBILITY
-case "$host" in
-*-*-linux*) ;;
-*) AC_MSG_ERROR([Linux only, dude!]);;
-esac
-
 regular_CPPFLAGS="-D_FILE_OFFSET_BITS=64 -D_REENTRANT"
 regular_CFLAGS="-Wall -Waggregate-return -Wmissing-declarations \
 	-Wmissing-prototypes -Wshadow -Wstrict-prototypes \
 	-Wformat=2 -pipe"
+
+case "$host" in
+*-*-linux*)
+	;;
+*)
+	regular_CPPFLAGS="$regular_CPPFLAGS "'-I${top_srcdir}/include/generic';;
+esac;
+
 AC_SUBST([regular_CPPFLAGS])
 AC_SUBST([regular_CFLAGS])
 AC_CONFIG_FILES([Makefile src/Makefile include/Makefile include/libmnl/Makefile include/linux/Makefile examples/Makefile examples/genl/Makefile examples/netfilter/Makefile examples/rtnl/Makefile libmnl.pc doxygen.cfg])
diff --git a/include/generic/linux/netlink.h b/include/generic/linux/netlink.h
new file mode 100644
index 0000000..0988284
--- /dev/null
+++ b/include/generic/linux/netlink.h
@@ -0,0 +1,152 @@
+#ifndef __LINUX_NETLINK_H
+#define __LINUX_NETLINK_H
+
+#include <stdint.h>
+#include <sys/socket.h> /* for sa_family_t */
+
+#ifndef AF_NETLINK
+#	define AF_NETLINK 0
+#endif
+
+#define NETLINK_ROUTE		0	/* Routing/device hook				*/
+#define NETLINK_UNUSED		1	/* Unused number				*/
+#define NETLINK_USERSOCK	2	/* Reserved for user mode socket protocols 	*/
+#define NETLINK_FIREWALL	3	/* Firewalling hook				*/
+#define NETLINK_INET_DIAG	4	/* INET socket monitoring			*/
+#define NETLINK_NFLOG		5	/* netfilter/iptables ULOG */
+#define NETLINK_XFRM		6	/* ipsec */
+#define NETLINK_SELINUX		7	/* SELinux event notifications */
+#define NETLINK_ISCSI		8	/* Open-iSCSI */
+#define NETLINK_AUDIT		9	/* auditing */
+#define NETLINK_FIB_LOOKUP	10	
+#define NETLINK_CONNECTOR	11
+#define NETLINK_NETFILTER	12	/* netfilter subsystem */
+#define NETLINK_IP6_FW		13
+#define NETLINK_DNRTMSG		14	/* DECnet routing messages */
+#define NETLINK_KOBJECT_UEVENT	15	/* Kernel messages to userspace */
+#define NETLINK_GENERIC		16
+/* leave room for NETLINK_DM (DM Events) */
+#define NETLINK_SCSITRANSPORT	18	/* SCSI Transports */
+#define NETLINK_ECRYPTFS	19
+
+#define MAX_LINKS 32		
+
+struct sockaddr_nl {
+	sa_family_t	nl_family;	/* AF_NETLINK	*/
+	unsigned short	nl_pad;		/* zero		*/
+	uint32_t		nl_pid;		/* port ID	*/
+       	uint32_t		nl_groups;	/* multicast groups mask */
+};
+
+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 port ID */
+};
+
+/* Flags values */
+
+#define NLM_F_REQUEST		1	/* It is request message. 	*/
+#define NLM_F_MULTI		2	/* Multipart message, terminated by NLMSG_DONE */
+#define NLM_F_ACK		4	/* Reply with ack, with zero or error code */
+#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	4U
+#define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
+#define NLMSG_HDRLEN	 ((int) NLMSG_ALIGN(sizeof(struct nlmsghdr)))
+#define NLMSG_LENGTH(len) ((len)+NLMSG_ALIGN(NLMSG_HDRLEN))
+#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) >= (int)sizeof(struct nlmsghdr) && \
+			   (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		*/
+
+#define NLMSG_MIN_TYPE		0x10	/* < 0x10: reserved control messages */
+
+struct nlmsgerr {
+	int		error;
+	struct nlmsghdr msg;
+};
+
+#define NETLINK_ADD_MEMBERSHIP	1
+#define NETLINK_DROP_MEMBERSHIP	2
+#define NETLINK_PKTINFO		3
+#define NETLINK_BROADCAST_ERROR	4
+#define NETLINK_NO_ENOBUFS	5
+
+struct nl_pktinfo {
+	uint32_t	group;
+};
+
+#define NET_MAJOR 36		/* Major 36 is reserved for networking 						*/
+
+enum {
+	NETLINK_UNCONNECTED = 0,
+	NETLINK_CONNECTED,
+};
+
+/*
+ *  <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)-->
+ * +---------------------+- - -+- - - - - - - - - -+- - -+
+ * |        Header       | Pad |     Payload       | Pad |
+ * |   (struct nlattr)   | ing |                   | ing |
+ * +---------------------+- - -+- - - - - - - - - -+- - -+
+ *  <-------------- nlattr->nla_len -------------->
+ */
+
+struct nlattr {
+	uint16_t           nla_len;
+	uint16_t           nla_type;
+};
+
+/*
+ * nla_type (16 bits)
+ * +---+---+-------------------------------+
+ * | N | O | Attribute Type                |
+ * +---+---+-------------------------------+
+ * N := Carries nested attributes
+ * O := Payload stored in network byte order
+ *
+ * Note: The N and O flag are mutually exclusive.
+ */
+#define NLA_F_NESTED		(1 << 15)
+#define NLA_F_NET_BYTEORDER	(1 << 14)
+#define NLA_TYPE_MASK		~(NLA_F_NESTED | NLA_F_NET_BYTEORDER)
+
+#define NLA_ALIGNTO		4
+#define NLA_ALIGN(len)		(((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1))
+#define NLA_HDRLEN		((int) NLA_ALIGN(sizeof(struct nlattr)))
+
+
+#endif	/* __LINUX_NETLINK_H */
-- 
1.7.1

Re: [PATCH 1/3] src: use limits.h header

[Pablo Neira Ayuso]

On 05/03/11 13:31, Jan Engelhardt wrote:
> values.h is not present on other systems, and the glibc copy reads
> right away: Old compatibility names for <limits.h> and <float.h>
> constants.

Applied, thanks Jan.

Re: [PATCH 2/3] include: use sanitized header from headers_install

[Pablo Neira Ayuso]

On 05/03/11 13:31, Jan Engelhardt wrote:
> Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
> ---
>  include/linux/netlink.h |  128 +----------------------------------------------
>  1 files changed, 1 insertions(+), 127 deletions(-)

Also applied, thanks

Re: [PATCH 3/3] build: support compilation on non-Linuxes

[Pablo Neira Ayuso]

On 05/03/11 13:31, Jan Engelhardt wrote:
> Netlink is a usable TLV protocol for IPC (e.g. over AF_LOCAL sockets)
> in itself even if other operating systems do not have kernel support
> for it.
> This tested on FreeBSD 8.2.

Interesting, I'll apply some example file to the tree if you have it.

One comment:

> ---
>  configure.ac                    |   13 ++--
>  include/generic/linux/netlink.h |  152 +++++++++++++++++++++++++++++++++++++++

This duplicates the header that it's in include/linux/netlink.h, the
only difference that I see at a quick glance is:

+#ifndef AF_NETLINK
+#	define AF_NETLINK 0
+#endif

right?

I have kept this patch until we've got some discussion.

Re: [PATCH 3/3] build: support compilation on non-Linuxes

[Jan Engelhardt]

On Wednesday 2011-03-09 14:53, Pablo Neira Ayuso wrote:
>
>One comment:
>
>> ---
>>  configure.ac                    |   13 ++--
>>  include/generic/linux/netlink.h |  152 +++++++++++++++++++++++++++++++++++++++
>
>This duplicates the header that it's in include/linux/netlink.h, the
>only difference that I see at a quick glance is:
>
>+#ifndef AF_NETLINK
>+#	define AF_NETLINK 0
>+#endif
>
>right?
>
>I have kept this patch until we've got some discussion.

And replacing __u16/32 by uint16_t/32_t plus #include <stdint.h>
because Other OS don't have linux/types.h (and all the other linux/ 
includes that will be pulled in as a result of it).