xref: /linux/net/rxrpc/local_event.c (revision 87c9c16317882dd6dbbc07e349bc3223e14f3244)
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 const char rxrpc_version_string[65] = "linux-" UTS_RELEASE " AF_RXRPC";
20 
21 /*
22  * Reply to a version request
23  */
24 static void rxrpc_send_version_request(struct rxrpc_local *local,
25 				       struct rxrpc_host_header *hdr,
26 				       struct sk_buff *skb)
27 {
28 	struct rxrpc_wire_header whdr;
29 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
30 	struct sockaddr_rxrpc srx;
31 	struct msghdr msg;
32 	struct kvec iov[2];
33 	size_t len;
34 	int ret;
35 
36 	_enter("");
37 
38 	if (rxrpc_extract_addr_from_skb(&srx, skb) < 0)
39 		return;
40 
41 	msg.msg_name	= &srx.transport;
42 	msg.msg_namelen	= srx.transport_len;
43 	msg.msg_control	= NULL;
44 	msg.msg_controllen = 0;
45 	msg.msg_flags	= 0;
46 
47 	whdr.epoch	= htonl(sp->hdr.epoch);
48 	whdr.cid	= htonl(sp->hdr.cid);
49 	whdr.callNumber	= htonl(sp->hdr.callNumber);
50 	whdr.seq	= 0;
51 	whdr.serial	= 0;
52 	whdr.type	= RXRPC_PACKET_TYPE_VERSION;
53 	whdr.flags	= RXRPC_LAST_PACKET | (~hdr->flags & RXRPC_CLIENT_INITIATED);
54 	whdr.userStatus	= 0;
55 	whdr.securityIndex = 0;
56 	whdr._rsvd	= 0;
57 	whdr.serviceId	= htons(sp->hdr.serviceId);
58 
59 	iov[0].iov_base	= &whdr;
60 	iov[0].iov_len	= sizeof(whdr);
61 	iov[1].iov_base	= (char *)rxrpc_version_string;
62 	iov[1].iov_len	= sizeof(rxrpc_version_string);
63 
64 	len = iov[0].iov_len + iov[1].iov_len;
65 
66 	_proto("Tx VERSION (reply)");
67 
68 	ret = kernel_sendmsg(local->socket, &msg, iov, 2, len);
69 	if (ret < 0)
70 		trace_rxrpc_tx_fail(local->debug_id, 0, ret,
71 				    rxrpc_tx_point_version_reply);
72 	else
73 		trace_rxrpc_tx_packet(local->debug_id, &whdr,
74 				      rxrpc_tx_point_version_reply);
75 
76 	_leave("");
77 }
78 
79 /*
80  * Process event packets targetted at a local endpoint.
81  */
82 void rxrpc_process_local_events(struct rxrpc_local *local)
83 {
84 	struct sk_buff *skb;
85 	char v;
86 
87 	_enter("");
88 
89 	skb = skb_dequeue(&local->event_queue);
90 	if (skb) {
91 		struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
92 
93 		rxrpc_see_skb(skb, rxrpc_skb_seen);
94 		_debug("{%d},{%u}", local->debug_id, sp->hdr.type);
95 
96 		switch (sp->hdr.type) {
97 		case RXRPC_PACKET_TYPE_VERSION:
98 			if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
99 					  &v, 1) < 0)
100 				return;
101 			_proto("Rx VERSION { %02x }", v);
102 			if (v == 0)
103 				rxrpc_send_version_request(local, &sp->hdr, skb);
104 			break;
105 
106 		default:
107 			/* Just ignore anything we don't understand */
108 			break;
109 		}
110 
111 		rxrpc_free_skb(skb, rxrpc_skb_freed);
112 	}
113 
114 	_leave("");
115 }
116