Commit 44ba0698 authored by David Howells's avatar David Howells
Browse files

RxRPC: Handle VERSION Rx protocol packets 



Handle VERSION Rx protocol packets.  We should respond to a VERSION packet
with a string indicating the Rx version.  This is a maximum of 64 characters
and is padded out to 65 chars with NUL bytes.

Note that other AFS clients use the version request as a NAT keepalive so we
need to handle it rather than returning an abort.

The standard formulation seems to be:

	<project> <version> built <yyyy>-<mm>-<dd>

for example:

	" OpenAFS 1.6.2 built  2013-05-07 "

(note the three extra spaces) as obtained with:

	rxdebug grand.mit.edu -version

from the openafs package.

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
parent bfd4e956

include/rxrpc/packet.h

+2 −1
Original line number Diff line number Diff line
@@ -47,7 +47,8 @@ struct rxrpc_header { 
#define RXRPC_PACKET_TYPE_CHALLENGE	6	/* connection security challenge (SRVR->CLNT) */

#define RXRPC_PACKET_TYPE_RESPONSE	7	/* connection secutity response (CLNT->SRVR) */

#define RXRPC_PACKET_TYPE_DEBUG		8	/* debug info request */

#define RXRPC_N_PACKET_TYPES		9	/* number of packet types (incl type 0) */

#define RXRPC_PACKET_TYPE_VERSION	13	/* version string request */

#define RXRPC_N_PACKET_TYPES		14	/* number of packet types (incl type 0) */



	uint8_t		flags;		/* packet flags */

#define RXRPC_CLIENT_INITIATED	0x01		/* signifies a packet generated by a client */

net/rxrpc/ar-input.c

+22 −1
Original line number Diff line number Diff line
@@ -28,7 +28,7 @@ 
const char *rxrpc_pkts[] = {

	"?00",

	"DATA", "ACK", "BUSY", "ABORT", "ACKALL", "CHALL", "RESP", "DEBUG",

	"?09", "?10", "?11", "?12", "?13", "?14", "?15"

	"?09", "?10", "?11", "?12", "VERSION", "?14", "?15"

};



/*
@@ -593,6 +593,20 @@ static void rxrpc_post_packet_to_conn(struct rxrpc_connection *conn, 
	rxrpc_queue_conn(conn);

}



/*

 * post endpoint-level events to the local endpoint

 * - this includes debug and version messages

 */

static void rxrpc_post_packet_to_local(struct rxrpc_local *local,

				       struct sk_buff *skb)

{

	_enter("%p,%p", local, skb);



	atomic_inc(&local->usage);

	skb_queue_tail(&local->event_queue, skb);

	rxrpc_queue_work(&local->event_processor);

}



static struct rxrpc_connection *rxrpc_conn_from_local(struct rxrpc_local *local,

					       struct sk_buff *skb,

					       struct rxrpc_skb_priv *sp)
@@ -699,6 +713,11 @@ void rxrpc_data_ready(struct sock *sk) 
		goto bad_message;

	}



	if (sp->hdr.type == RXRPC_PACKET_TYPE_VERSION) {

		rxrpc_post_packet_to_local(local, skb);

		goto out;

	}

	

	if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA &&

	    (sp->hdr.callNumber == 0 || sp->hdr.seq == 0))

		goto bad_message;
@@ -731,6 +750,8 @@ void rxrpc_data_ready(struct sock *sk) 
		else

			goto cant_route_call;

	}



out:

	rxrpc_put_local(local);

	return;

net/rxrpc/ar-internal.h

+2 −0
Original line number Diff line number Diff line
@@ -152,11 +152,13 @@ struct rxrpc_local { 
	struct work_struct	destroyer;	/* endpoint destroyer */

	struct work_struct	acceptor;	/* incoming call processor */

	struct work_struct	rejecter;	/* packet reject writer */

	struct work_struct	event_processor; /* endpoint event processor */

	struct list_head	services;	/* services listening on this endpoint */

	struct list_head	link;		/* link in endpoint list */

	struct rw_semaphore	defrag_sem;	/* control re-enablement of IP DF bit */

	struct sk_buff_head	accept_queue;	/* incoming calls awaiting acceptance */

	struct sk_buff_head	reject_queue;	/* packets awaiting rejection */

	struct sk_buff_head	event_queue;	/* endpoint event packets awaiting processing */

	spinlock_t		lock;		/* access lock */

	rwlock_t		services_lock;	/* lock for services list */

	atomic_t		usage;

net/rxrpc/ar-local.c

+98 −0
Original line number Diff line number Diff line
@@ -13,16 +13,22 @@ 
#include <linux/net.h>

#include <linux/skbuff.h>

#include <linux/slab.h>

#include <linux/udp.h>

#include <linux/ip.h>

#include <net/sock.h>

#include <net/af_rxrpc.h>

#include <generated/utsrelease.h>

#include "ar-internal.h"



static const char rxrpc_version_string[65] = "linux-" UTS_RELEASE " AF_RXRPC";



static LIST_HEAD(rxrpc_locals);

DEFINE_RWLOCK(rxrpc_local_lock);

static DECLARE_RWSEM(rxrpc_local_sem);

static DECLARE_WAIT_QUEUE_HEAD(rxrpc_local_wq);



static void rxrpc_destroy_local(struct work_struct *work);

static void rxrpc_process_local_events(struct work_struct *work);



/*

 * allocate a new local
@@ -37,11 +43,13 @@ struct rxrpc_local *rxrpc_alloc_local(struct sockaddr_rxrpc *srx) 
		INIT_WORK(&local->destroyer, &rxrpc_destroy_local);

		INIT_WORK(&local->acceptor, &rxrpc_accept_incoming_calls);

		INIT_WORK(&local->rejecter, &rxrpc_reject_packets);

		INIT_WORK(&local->event_processor, &rxrpc_process_local_events);

		INIT_LIST_HEAD(&local->services);

		INIT_LIST_HEAD(&local->link);

		init_rwsem(&local->defrag_sem);

		skb_queue_head_init(&local->accept_queue);

		skb_queue_head_init(&local->reject_queue);

		skb_queue_head_init(&local->event_queue);

		spin_lock_init(&local->lock);

		rwlock_init(&local->services_lock);

		atomic_set(&local->usage, 1);
@@ -264,10 +272,12 @@ static void rxrpc_destroy_local(struct work_struct *work) 
	ASSERT(list_empty(&local->services));

	ASSERT(!work_pending(&local->acceptor));

	ASSERT(!work_pending(&local->rejecter));

	ASSERT(!work_pending(&local->event_processor));



	/* finish cleaning up the local descriptor */

	rxrpc_purge_queue(&local->accept_queue);

	rxrpc_purge_queue(&local->reject_queue);

	rxrpc_purge_queue(&local->event_queue);

	kernel_sock_shutdown(local->socket, SHUT_RDWR);

	sock_release(local->socket);
@@ -308,3 +318,91 @@ void __exit rxrpc_destroy_all_locals(void) 


	_leave("");

}



/*

 * Reply to a version request

 */

static void rxrpc_send_version_request(struct rxrpc_local *local,

				       struct rxrpc_header *hdr,

				       struct sk_buff *skb)

{

	struct sockaddr_in sin;

	struct msghdr msg;

	struct kvec iov[2];

	size_t len;

	int ret;



	_enter("");



	sin.sin_family = AF_INET;

	sin.sin_port = udp_hdr(skb)->source;

	sin.sin_addr.s_addr = ip_hdr(skb)->saddr;



	msg.msg_name	= &sin;

	msg.msg_namelen	= sizeof(sin);

	msg.msg_control	= NULL;

	msg.msg_controllen = 0;

	msg.msg_flags	= 0;



	hdr->seq	= 0;

	hdr->serial	= 0;

	hdr->type	= RXRPC_PACKET_TYPE_VERSION;

	hdr->flags	= RXRPC_LAST_PACKET | (~hdr->flags & RXRPC_CLIENT_INITIATED);

	hdr->userStatus	= 0;

	hdr->_rsvd	= 0;



	iov[0].iov_base	= hdr;

	iov[0].iov_len	= sizeof(*hdr);

	iov[1].iov_base	= (char *)rxrpc_version_string;

	iov[1].iov_len	= sizeof(rxrpc_version_string);



	len = iov[0].iov_len + iov[1].iov_len;



	_proto("Tx VERSION (reply)");



	ret = kernel_sendmsg(local->socket, &msg, iov, 2, len);

	if (ret < 0)

		_debug("sendmsg failed: %d", ret);



	_leave("");

}



/*

 * Process event packets targetted at a local endpoint.

 */

static void rxrpc_process_local_events(struct work_struct *work)

{

	struct rxrpc_local *local = container_of(work, struct rxrpc_local, event_processor);

	struct sk_buff *skb;

	char v;



	_enter("");



	atomic_inc(&local->usage);

	

	while ((skb = skb_dequeue(&local->event_queue))) {

		struct rxrpc_skb_priv *sp = rxrpc_skb(skb);



		kdebug("{%d},{%u}", local->debug_id, sp->hdr.type);



		switch (sp->hdr.type) {

		case RXRPC_PACKET_TYPE_VERSION:

			if (skb_copy_bits(skb, 0, &v, 1) < 0)

				return;

			_proto("Rx VERSION { %02x }", v);

			if (v == 0)

				rxrpc_send_version_request(local, &sp->hdr, skb);

			break;



		default:

			/* Just ignore anything we don't understand */

			break;

		}



		rxrpc_put_local(local);

		rxrpc_free_skb(skb);

	}



	rxrpc_put_local(local);

	_leave("");

}

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