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: David Howells <dhowells@redhat.com>
This commit is contained in:
David Howells 2015-04-01 16:31:26 +01:00
parent bfd4e9562c
commit 44ba06987c
4 changed files with 124 additions and 2 deletions

View File

@ -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 */

View File

@ -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;

View File

@ -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;

View File

@ -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("");
}