1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* AF_RXRPC local endpoint management
3  *
4  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
5  * Written by David Howells (dhowells@redhat.com)
6  */
7 
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9 
10 #include <linux/module.h>
11 #include <linux/net.h>
12 #include <linux/skbuff.h>
13 #include <linux/slab.h>
14 #include <net/sock.h>
15 #include <net/af_rxrpc.h>
16 #include <generated/utsrelease.h>
17 #include "ar-internal.h"
18 
19 static char rxrpc_version_string[65]; // "linux-" UTS_RELEASE " AF_RXRPC";
20 
21 /*
22  * Generate the VERSION packet string.
23  */
rxrpc_gen_version_string(void)24 void rxrpc_gen_version_string(void)
25 {
26 	snprintf(rxrpc_version_string, sizeof(rxrpc_version_string),
27 		 "linux-%.49s AF_RXRPC", UTS_RELEASE);
28 }
29 
30 /*
31  * Reply to a version request
32  */
rxrpc_send_version_request(struct rxrpc_local * local,struct rxrpc_host_header * hdr,struct sk_buff * skb)33 void rxrpc_send_version_request(struct rxrpc_local *local,
34 				struct rxrpc_host_header *hdr,
35 				struct sk_buff *skb)
36 {
37 	struct rxrpc_wire_header whdr;
38 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
39 	struct sockaddr_rxrpc srx;
40 	struct msghdr msg;
41 	struct kvec iov[2];
42 	size_t len;
43 	int ret;
44 
45 	_enter("");
46 
47 	if (rxrpc_extract_addr_from_skb(&srx, skb) < 0)
48 		return;
49 
50 	msg.msg_name	= &srx.transport;
51 	msg.msg_namelen	= srx.transport_len;
52 	msg.msg_control	= NULL;
53 	msg.msg_controllen = 0;
54 	msg.msg_flags	= 0;
55 
56 	whdr.epoch	= htonl(sp->hdr.epoch);
57 	whdr.cid	= htonl(sp->hdr.cid);
58 	whdr.callNumber	= htonl(sp->hdr.callNumber);
59 	whdr.seq	= 0;
60 	whdr.serial	= 0;
61 	whdr.type	= RXRPC_PACKET_TYPE_VERSION;
62 	whdr.flags	= RXRPC_LAST_PACKET | (~hdr->flags & RXRPC_CLIENT_INITIATED);
63 	whdr.userStatus	= 0;
64 	whdr.securityIndex = 0;
65 	whdr._rsvd	= 0;
66 	whdr.serviceId	= htons(sp->hdr.serviceId);
67 
68 	iov[0].iov_base	= &whdr;
69 	iov[0].iov_len	= sizeof(whdr);
70 	iov[1].iov_base	= (char *)rxrpc_version_string;
71 	iov[1].iov_len	= sizeof(rxrpc_version_string);
72 
73 	len = iov[0].iov_len + iov[1].iov_len;
74 
75 	ret = kernel_sendmsg(local->socket, &msg, iov, 2, len);
76 	if (ret < 0)
77 		trace_rxrpc_tx_fail(local->debug_id, 0, ret,
78 				    rxrpc_tx_point_version_reply);
79 	else
80 		trace_rxrpc_tx_packet(local->debug_id, &whdr,
81 				      rxrpc_tx_point_version_reply);
82 
83 	_leave("");
84 }
85