1 /* connection-level event handling
2 *
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12 #include <linux/module.h>
13 #include <linux/net.h>
14 #include <linux/skbuff.h>
15 #include <linux/errqueue.h>
16 #include <linux/udp.h>
17 #include <linux/in.h>
18 #include <linux/in6.h>
19 #include <linux/icmp.h>
20 #include <net/sock.h>
21 #include <net/af_rxrpc.h>
22 #include <net/ip.h>
23 #include "ar-internal.h"
24
25 /*
26 * pass a connection-level abort onto all calls on that connection
27 */
rxrpc_abort_calls(struct rxrpc_connection * conn,int state,u32 abort_code)28 static void rxrpc_abort_calls(struct rxrpc_connection *conn, int state,
29 u32 abort_code)
30 {
31 struct rxrpc_call *call;
32 struct rb_node *p;
33
34 _enter("{%d},%x", conn->debug_id, abort_code);
35
36 read_lock_bh(&conn->lock);
37
38 for (p = rb_first(&conn->calls); p; p = rb_next(p)) {
39 call = rb_entry(p, struct rxrpc_call, conn_node);
40 write_lock(&call->state_lock);
41 if (call->state <= RXRPC_CALL_COMPLETE) {
42 call->state = state;
43 call->abort_code = abort_code;
44 if (state == RXRPC_CALL_LOCALLY_ABORTED)
45 set_bit(RXRPC_CALL_CONN_ABORT, &call->events);
46 else
47 set_bit(RXRPC_CALL_RCVD_ABORT, &call->events);
48 rxrpc_queue_call(call);
49 }
50 write_unlock(&call->state_lock);
51 }
52
53 read_unlock_bh(&conn->lock);
54 _leave("");
55 }
56
57 /*
58 * generate a connection-level abort
59 */
rxrpc_abort_connection(struct rxrpc_connection * conn,u32 error,u32 abort_code)60 static int rxrpc_abort_connection(struct rxrpc_connection *conn,
61 u32 error, u32 abort_code)
62 {
63 struct rxrpc_header hdr;
64 struct msghdr msg;
65 struct kvec iov[2];
66 __be32 word;
67 size_t len;
68 int ret;
69
70 _enter("%d,,%u,%u", conn->debug_id, error, abort_code);
71
72 /* generate a connection-level abort */
73 spin_lock_bh(&conn->state_lock);
74 if (conn->state < RXRPC_CONN_REMOTELY_ABORTED) {
75 conn->state = RXRPC_CONN_LOCALLY_ABORTED;
76 conn->error = error;
77 spin_unlock_bh(&conn->state_lock);
78 } else {
79 spin_unlock_bh(&conn->state_lock);
80 _leave(" = 0 [already dead]");
81 return 0;
82 }
83
84 rxrpc_abort_calls(conn, RXRPC_CALL_LOCALLY_ABORTED, abort_code);
85
86 msg.msg_name = &conn->trans->peer->srx.transport.sin;
87 msg.msg_namelen = sizeof(conn->trans->peer->srx.transport.sin);
88 msg.msg_control = NULL;
89 msg.msg_controllen = 0;
90 msg.msg_flags = 0;
91
92 hdr.epoch = conn->epoch;
93 hdr.cid = conn->cid;
94 hdr.callNumber = 0;
95 hdr.seq = 0;
96 hdr.type = RXRPC_PACKET_TYPE_ABORT;
97 hdr.flags = conn->out_clientflag;
98 hdr.userStatus = 0;
99 hdr.securityIndex = conn->security_ix;
100 hdr._rsvd = 0;
101 hdr.serviceId = conn->service_id;
102
103 word = htonl(abort_code);
104
105 iov[0].iov_base = &hdr;
106 iov[0].iov_len = sizeof(hdr);
107 iov[1].iov_base = &word;
108 iov[1].iov_len = sizeof(word);
109
110 len = iov[0].iov_len + iov[1].iov_len;
111
112 hdr.serial = htonl(atomic_inc_return(&conn->serial));
113 _proto("Tx CONN ABORT %%%u { %d }", ntohl(hdr.serial), abort_code);
114
115 ret = kernel_sendmsg(conn->trans->local->socket, &msg, iov, 2, len);
116 if (ret < 0) {
117 _debug("sendmsg failed: %d", ret);
118 return -EAGAIN;
119 }
120
121 _leave(" = 0");
122 return 0;
123 }
124
125 /*
126 * mark a call as being on a now-secured channel
127 * - must be called with softirqs disabled
128 */
rxrpc_call_is_secure(struct rxrpc_call * call)129 static void rxrpc_call_is_secure(struct rxrpc_call *call)
130 {
131 _enter("%p", call);
132 if (call) {
133 read_lock(&call->state_lock);
134 if (call->state < RXRPC_CALL_COMPLETE &&
135 !test_and_set_bit(RXRPC_CALL_SECURED, &call->events))
136 rxrpc_queue_call(call);
137 read_unlock(&call->state_lock);
138 }
139 }
140
141 /*
142 * connection-level Rx packet processor
143 */
rxrpc_process_event(struct rxrpc_connection * conn,struct sk_buff * skb,u32 * _abort_code)144 static int rxrpc_process_event(struct rxrpc_connection *conn,
145 struct sk_buff *skb,
146 u32 *_abort_code)
147 {
148 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
149 __be32 tmp;
150 u32 serial;
151 int loop, ret;
152
153 if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED)
154 return -ECONNABORTED;
155
156 serial = ntohl(sp->hdr.serial);
157
158 switch (sp->hdr.type) {
159 case RXRPC_PACKET_TYPE_ABORT:
160 if (skb_copy_bits(skb, 0, &tmp, sizeof(tmp)) < 0)
161 return -EPROTO;
162 _proto("Rx ABORT %%%u { ac=%d }", serial, ntohl(tmp));
163
164 conn->state = RXRPC_CONN_REMOTELY_ABORTED;
165 rxrpc_abort_calls(conn, RXRPC_CALL_REMOTELY_ABORTED,
166 ntohl(tmp));
167 return -ECONNABORTED;
168
169 case RXRPC_PACKET_TYPE_CHALLENGE:
170 if (conn->security)
171 return conn->security->respond_to_challenge(
172 conn, skb, _abort_code);
173 return -EPROTO;
174
175 case RXRPC_PACKET_TYPE_RESPONSE:
176 if (!conn->security)
177 return -EPROTO;
178
179 ret = conn->security->verify_response(conn, skb, _abort_code);
180 if (ret < 0)
181 return ret;
182
183 ret = conn->security->init_connection_security(conn);
184 if (ret < 0)
185 return ret;
186
187 conn->security->prime_packet_security(conn);
188 read_lock_bh(&conn->lock);
189 spin_lock(&conn->state_lock);
190
191 if (conn->state == RXRPC_CONN_SERVER_CHALLENGING) {
192 conn->state = RXRPC_CONN_SERVER;
193 for (loop = 0; loop < RXRPC_MAXCALLS; loop++)
194 rxrpc_call_is_secure(conn->channels[loop]);
195 }
196
197 spin_unlock(&conn->state_lock);
198 read_unlock_bh(&conn->lock);
199 return 0;
200
201 default:
202 return -EPROTO;
203 }
204 }
205
206 /*
207 * set up security and issue a challenge
208 */
rxrpc_secure_connection(struct rxrpc_connection * conn)209 static void rxrpc_secure_connection(struct rxrpc_connection *conn)
210 {
211 u32 abort_code;
212 int ret;
213
214 _enter("{%d}", conn->debug_id);
215
216 ASSERT(conn->security_ix != 0);
217
218 if (!conn->key) {
219 _debug("set up security");
220 ret = rxrpc_init_server_conn_security(conn);
221 switch (ret) {
222 case 0:
223 break;
224 case -ENOENT:
225 abort_code = RX_CALL_DEAD;
226 goto abort;
227 default:
228 abort_code = RXKADNOAUTH;
229 goto abort;
230 }
231 }
232
233 ASSERT(conn->security != NULL);
234
235 if (conn->security->issue_challenge(conn) < 0) {
236 abort_code = RX_CALL_DEAD;
237 ret = -ENOMEM;
238 goto abort;
239 }
240
241 _leave("");
242 return;
243
244 abort:
245 _debug("abort %d, %d", ret, abort_code);
246 rxrpc_abort_connection(conn, -ret, abort_code);
247 _leave(" [aborted]");
248 }
249
250 /*
251 * connection-level event processor
252 */
rxrpc_process_connection(struct work_struct * work)253 void rxrpc_process_connection(struct work_struct *work)
254 {
255 struct rxrpc_connection *conn =
256 container_of(work, struct rxrpc_connection, processor);
257 struct rxrpc_skb_priv *sp;
258 struct sk_buff *skb;
259 u32 abort_code = RX_PROTOCOL_ERROR;
260 int ret;
261
262 _enter("{%d}", conn->debug_id);
263
264 atomic_inc(&conn->usage);
265
266 if (test_and_clear_bit(RXRPC_CONN_CHALLENGE, &conn->events)) {
267 rxrpc_secure_connection(conn);
268 rxrpc_put_connection(conn);
269 }
270
271 /* go through the conn-level event packets, releasing the ref on this
272 * connection that each one has when we've finished with it */
273 while ((skb = skb_dequeue(&conn->rx_queue))) {
274 sp = rxrpc_skb(skb);
275
276 ret = rxrpc_process_event(conn, skb, &abort_code);
277 switch (ret) {
278 case -EPROTO:
279 case -EKEYEXPIRED:
280 case -EKEYREJECTED:
281 goto protocol_error;
282 case -EAGAIN:
283 goto requeue_and_leave;
284 case -ECONNABORTED:
285 default:
286 rxrpc_put_connection(conn);
287 rxrpc_free_skb(skb);
288 break;
289 }
290 }
291
292 out:
293 rxrpc_put_connection(conn);
294 _leave("");
295 return;
296
297 requeue_and_leave:
298 skb_queue_head(&conn->rx_queue, skb);
299 goto out;
300
301 protocol_error:
302 if (rxrpc_abort_connection(conn, -ret, abort_code) < 0)
303 goto requeue_and_leave;
304 rxrpc_put_connection(conn);
305 rxrpc_free_skb(skb);
306 _leave(" [EPROTO]");
307 goto out;
308 }
309
310 /*
311 * put a packet up for transport-level abort
312 */
rxrpc_reject_packet(struct rxrpc_local * local,struct sk_buff * skb)313 void rxrpc_reject_packet(struct rxrpc_local *local, struct sk_buff *skb)
314 {
315 CHECK_SLAB_OKAY(&local->usage);
316
317 if (!atomic_inc_not_zero(&local->usage)) {
318 printk("resurrected on reject\n");
319 BUG();
320 }
321
322 skb_queue_tail(&local->reject_queue, skb);
323 rxrpc_queue_work(&local->rejecter);
324 }
325
326 /*
327 * reject packets through the local endpoint
328 */
rxrpc_reject_packets(struct work_struct * work)329 void rxrpc_reject_packets(struct work_struct *work)
330 {
331 union {
332 struct sockaddr sa;
333 struct sockaddr_in sin;
334 } sa;
335 struct rxrpc_skb_priv *sp;
336 struct rxrpc_header hdr;
337 struct rxrpc_local *local;
338 struct sk_buff *skb;
339 struct msghdr msg;
340 struct kvec iov[2];
341 size_t size;
342 __be32 code;
343
344 local = container_of(work, struct rxrpc_local, rejecter);
345 rxrpc_get_local(local);
346
347 _enter("%d", local->debug_id);
348
349 iov[0].iov_base = &hdr;
350 iov[0].iov_len = sizeof(hdr);
351 iov[1].iov_base = &code;
352 iov[1].iov_len = sizeof(code);
353 size = sizeof(hdr) + sizeof(code);
354
355 msg.msg_name = &sa;
356 msg.msg_control = NULL;
357 msg.msg_controllen = 0;
358 msg.msg_flags = 0;
359
360 memset(&sa, 0, sizeof(sa));
361 sa.sa.sa_family = local->srx.transport.family;
362 switch (sa.sa.sa_family) {
363 case AF_INET:
364 msg.msg_namelen = sizeof(sa.sin);
365 break;
366 default:
367 msg.msg_namelen = 0;
368 break;
369 }
370
371 memset(&hdr, 0, sizeof(hdr));
372 hdr.type = RXRPC_PACKET_TYPE_ABORT;
373
374 while ((skb = skb_dequeue(&local->reject_queue))) {
375 sp = rxrpc_skb(skb);
376 switch (sa.sa.sa_family) {
377 case AF_INET:
378 sa.sin.sin_port = udp_hdr(skb)->source;
379 sa.sin.sin_addr.s_addr = ip_hdr(skb)->saddr;
380 code = htonl(skb->priority);
381
382 hdr.epoch = sp->hdr.epoch;
383 hdr.cid = sp->hdr.cid;
384 hdr.callNumber = sp->hdr.callNumber;
385 hdr.serviceId = sp->hdr.serviceId;
386 hdr.flags = sp->hdr.flags;
387 hdr.flags ^= RXRPC_CLIENT_INITIATED;
388 hdr.flags &= RXRPC_CLIENT_INITIATED;
389
390 kernel_sendmsg(local->socket, &msg, iov, 2, size);
391 break;
392
393 default:
394 break;
395 }
396
397 rxrpc_free_skb(skb);
398 rxrpc_put_local(local);
399 }
400
401 rxrpc_put_local(local);
402 _leave("");
403 }
404