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Commit | Line | Data |
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17926a79 DH |
1 | /* RxRPC packet reception |
2 | * | |
248f219c | 3 | * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved. |
17926a79 DH |
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 | ||
9b6d5398 JP |
12 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
13 | ||
17926a79 DH |
14 | #include <linux/module.h> |
15 | #include <linux/net.h> | |
16 | #include <linux/skbuff.h> | |
17 | #include <linux/errqueue.h> | |
18 | #include <linux/udp.h> | |
19 | #include <linux/in.h> | |
20 | #include <linux/in6.h> | |
21 | #include <linux/icmp.h> | |
5a0e3ad6 | 22 | #include <linux/gfp.h> |
17926a79 DH |
23 | #include <net/sock.h> |
24 | #include <net/af_rxrpc.h> | |
25 | #include <net/ip.h> | |
1781f7f5 | 26 | #include <net/udp.h> |
0283328e | 27 | #include <net/net_namespace.h> |
17926a79 DH |
28 | #include "ar-internal.h" |
29 | ||
248f219c DH |
30 | static void rxrpc_proto_abort(const char *why, |
31 | struct rxrpc_call *call, rxrpc_seq_t seq) | |
32 | { | |
33 | if (rxrpc_abort_call(why, call, seq, RX_PROTOCOL_ERROR, EBADMSG)) { | |
34 | set_bit(RXRPC_CALL_EV_ABORT, &call->events); | |
35 | rxrpc_queue_call(call); | |
36 | } | |
37 | } | |
38 | ||
8e83134d DH |
39 | /* |
40 | * Ping the other end to fill our RTT cache and to retrieve the rwind | |
41 | * and MTU parameters. | |
42 | */ | |
43 | static void rxrpc_send_ping(struct rxrpc_call *call, struct sk_buff *skb, | |
44 | int skew) | |
45 | { | |
46 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); | |
fc943f67 | 47 | ktime_t now = skb->tstamp; |
8e83134d | 48 | |
fc943f67 DH |
49 | if (call->peer->rtt_usage < 3 || |
50 | ktime_before(ktime_add_ms(call->peer->rtt_last_req, 1000), now)) | |
51 | rxrpc_propose_ACK(call, RXRPC_ACK_PING, skew, sp->hdr.serial, | |
52 | true, true); | |
8e83134d DH |
53 | } |
54 | ||
17926a79 | 55 | /* |
248f219c | 56 | * Apply a hard ACK by advancing the Tx window. |
17926a79 | 57 | */ |
248f219c | 58 | static void rxrpc_rotate_tx_window(struct rxrpc_call *call, rxrpc_seq_t to) |
17926a79 | 59 | { |
248f219c DH |
60 | struct sk_buff *skb, *list = NULL; |
61 | int ix; | |
17926a79 | 62 | |
248f219c | 63 | spin_lock(&call->lock); |
17926a79 | 64 | |
248f219c DH |
65 | while (before(call->tx_hard_ack, to)) { |
66 | call->tx_hard_ack++; | |
67 | ix = call->tx_hard_ack & RXRPC_RXTX_BUFF_MASK; | |
68 | skb = call->rxtx_buffer[ix]; | |
71f3ca40 | 69 | rxrpc_see_skb(skb, rxrpc_skb_tx_rotated); |
248f219c DH |
70 | call->rxtx_buffer[ix] = NULL; |
71 | call->rxtx_annotations[ix] = 0; | |
72 | skb->next = list; | |
73 | list = skb; | |
74 | } | |
17926a79 | 75 | |
248f219c | 76 | spin_unlock(&call->lock); |
17926a79 | 77 | |
a124fe3e | 78 | trace_rxrpc_transmit(call, rxrpc_transmit_rotate); |
bc4abfcf DH |
79 | wake_up(&call->waitq); |
80 | ||
248f219c DH |
81 | while (list) { |
82 | skb = list; | |
83 | list = skb->next; | |
84 | skb->next = NULL; | |
71f3ca40 | 85 | rxrpc_free_skb(skb, rxrpc_skb_tx_freed); |
17926a79 | 86 | } |
248f219c | 87 | } |
17926a79 | 88 | |
248f219c DH |
89 | /* |
90 | * End the transmission phase of a call. | |
91 | * | |
92 | * This occurs when we get an ACKALL packet, the first DATA packet of a reply, | |
93 | * or a final ACK packet. | |
94 | */ | |
95 | static bool rxrpc_end_tx_phase(struct rxrpc_call *call, const char *abort_why) | |
96 | { | |
97 | _enter(""); | |
17926a79 | 98 | |
248f219c DH |
99 | switch (call->state) { |
100 | case RXRPC_CALL_CLIENT_RECV_REPLY: | |
101 | return true; | |
102 | case RXRPC_CALL_CLIENT_AWAIT_REPLY: | |
103 | case RXRPC_CALL_SERVER_AWAIT_ACK: | |
104 | break; | |
105 | default: | |
106 | rxrpc_proto_abort(abort_why, call, call->tx_top); | |
107 | return false; | |
17926a79 DH |
108 | } |
109 | ||
248f219c | 110 | rxrpc_rotate_tx_window(call, call->tx_top); |
17926a79 | 111 | |
248f219c | 112 | write_lock(&call->state_lock); |
651350d1 | 113 | |
248f219c DH |
114 | switch (call->state) { |
115 | default: | |
116 | break; | |
117 | case RXRPC_CALL_CLIENT_AWAIT_REPLY: | |
71f3ca40 | 118 | call->tx_phase = false; |
248f219c DH |
119 | call->state = RXRPC_CALL_CLIENT_RECV_REPLY; |
120 | break; | |
121 | case RXRPC_CALL_SERVER_AWAIT_ACK: | |
122 | __rxrpc_call_completed(call); | |
123 | rxrpc_notify_socket(call); | |
124 | break; | |
17926a79 | 125 | } |
17926a79 | 126 | |
248f219c | 127 | write_unlock(&call->state_lock); |
a124fe3e | 128 | trace_rxrpc_transmit(call, rxrpc_transmit_end); |
248f219c DH |
129 | _leave(" = ok"); |
130 | return true; | |
131 | } | |
132 | ||
133 | /* | |
134 | * Scan a jumbo packet to validate its structure and to work out how many | |
135 | * subpackets it contains. | |
136 | * | |
137 | * A jumbo packet is a collection of consecutive packets glued together with | |
138 | * little headers between that indicate how to change the initial header for | |
139 | * each subpacket. | |
140 | * | |
141 | * RXRPC_JUMBO_PACKET must be set on all but the last subpacket - and all but | |
142 | * the last are RXRPC_JUMBO_DATALEN in size. The last subpacket may be of any | |
143 | * size. | |
144 | */ | |
145 | static bool rxrpc_validate_jumbo(struct sk_buff *skb) | |
146 | { | |
147 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); | |
148 | unsigned int offset = sp->offset; | |
89a80ed4 | 149 | unsigned int len = skb->len; |
248f219c DH |
150 | int nr_jumbo = 1; |
151 | u8 flags = sp->hdr.flags; | |
152 | ||
153 | do { | |
154 | nr_jumbo++; | |
155 | if (len - offset < RXRPC_JUMBO_SUBPKTLEN) | |
156 | goto protocol_error; | |
157 | if (flags & RXRPC_LAST_PACKET) | |
158 | goto protocol_error; | |
159 | offset += RXRPC_JUMBO_DATALEN; | |
160 | if (skb_copy_bits(skb, offset, &flags, 1) < 0) | |
161 | goto protocol_error; | |
162 | offset += sizeof(struct rxrpc_jumbo_header); | |
163 | } while (flags & RXRPC_JUMBO_PACKET); | |
164 | ||
165 | sp->nr_jumbo = nr_jumbo; | |
166 | return true; | |
17926a79 | 167 | |
248f219c DH |
168 | protocol_error: |
169 | return false; | |
17926a79 DH |
170 | } |
171 | ||
172 | /* | |
248f219c DH |
173 | * Handle reception of a duplicate packet. |
174 | * | |
175 | * We have to take care to avoid an attack here whereby we're given a series of | |
176 | * jumbograms, each with a sequence number one before the preceding one and | |
177 | * filled up to maximum UDP size. If they never send us the first packet in | |
178 | * the sequence, they can cause us to have to hold on to around 2MiB of kernel | |
179 | * space until the call times out. | |
180 | * | |
181 | * We limit the space usage by only accepting three duplicate jumbo packets per | |
182 | * call. After that, we tell the other side we're no longer accepting jumbos | |
183 | * (that information is encoded in the ACK packet). | |
17926a79 | 184 | */ |
248f219c | 185 | static void rxrpc_input_dup_data(struct rxrpc_call *call, rxrpc_seq_t seq, |
75e42126 | 186 | u8 annotation, bool *_jumbo_bad) |
17926a79 | 187 | { |
248f219c DH |
188 | /* Discard normal packets that are duplicates. */ |
189 | if (annotation == 0) | |
190 | return; | |
17926a79 | 191 | |
248f219c DH |
192 | /* Skip jumbo subpackets that are duplicates. When we've had three or |
193 | * more partially duplicate jumbo packets, we refuse to take any more | |
194 | * jumbos for this call. | |
195 | */ | |
75e42126 DH |
196 | if (!*_jumbo_bad) { |
197 | call->nr_jumbo_bad++; | |
198 | *_jumbo_bad = true; | |
248f219c DH |
199 | } |
200 | } | |
17926a79 | 201 | |
248f219c DH |
202 | /* |
203 | * Process a DATA packet, adding the packet to the Rx ring. | |
204 | */ | |
205 | static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb, | |
206 | u16 skew) | |
207 | { | |
208 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); | |
209 | unsigned int offset = sp->offset; | |
210 | unsigned int ix; | |
211 | rxrpc_serial_t serial = sp->hdr.serial, ack_serial = 0; | |
212 | rxrpc_seq_t seq = sp->hdr.seq, hard_ack; | |
75e42126 | 213 | bool immediate_ack = false, jumbo_bad = false, queued; |
248f219c DH |
214 | u16 len; |
215 | u8 ack = 0, flags, annotation = 0; | |
17926a79 | 216 | |
248f219c | 217 | _enter("{%u,%u},{%u,%u}", |
89a80ed4 | 218 | call->rx_hard_ack, call->rx_top, skb->len, seq); |
17926a79 | 219 | |
248f219c DH |
220 | _proto("Rx DATA %%%u { #%u f=%02x }", |
221 | sp->hdr.serial, seq, sp->hdr.flags); | |
17926a79 | 222 | |
248f219c DH |
223 | if (call->state >= RXRPC_CALL_COMPLETE) |
224 | return; | |
17926a79 | 225 | |
248f219c DH |
226 | /* Received data implicitly ACKs all of the request packets we sent |
227 | * when we're acting as a client. | |
228 | */ | |
229 | if (call->state == RXRPC_CALL_CLIENT_AWAIT_REPLY && | |
230 | !rxrpc_end_tx_phase(call, "ETD")) | |
231 | return; | |
17926a79 | 232 | |
248f219c | 233 | call->ackr_prev_seq = seq; |
17926a79 | 234 | |
248f219c DH |
235 | hard_ack = READ_ONCE(call->rx_hard_ack); |
236 | if (after(seq, hard_ack + call->rx_winsize)) { | |
17926a79 | 237 | ack = RXRPC_ACK_EXCEEDS_WINDOW; |
248f219c DH |
238 | ack_serial = serial; |
239 | goto ack; | |
17926a79 DH |
240 | } |
241 | ||
248f219c DH |
242 | flags = sp->hdr.flags; |
243 | if (flags & RXRPC_JUMBO_PACKET) { | |
75e42126 | 244 | if (call->nr_jumbo_bad > 3) { |
248f219c DH |
245 | ack = RXRPC_ACK_NOSPACE; |
246 | ack_serial = serial; | |
247 | goto ack; | |
17926a79 | 248 | } |
248f219c | 249 | annotation = 1; |
17926a79 DH |
250 | } |
251 | ||
248f219c DH |
252 | next_subpacket: |
253 | queued = false; | |
254 | ix = seq & RXRPC_RXTX_BUFF_MASK; | |
89a80ed4 | 255 | len = skb->len; |
248f219c DH |
256 | if (flags & RXRPC_JUMBO_PACKET) |
257 | len = RXRPC_JUMBO_DATALEN; | |
258 | ||
259 | if (flags & RXRPC_LAST_PACKET) { | |
816c9fce | 260 | if (test_bit(RXRPC_CALL_RX_LAST, &call->flags) && |
248f219c DH |
261 | seq != call->rx_top) |
262 | return rxrpc_proto_abort("LSN", call, seq); | |
263 | } else { | |
264 | if (test_bit(RXRPC_CALL_RX_LAST, &call->flags) && | |
265 | after_eq(seq, call->rx_top)) | |
266 | return rxrpc_proto_abort("LSA", call, seq); | |
17926a79 DH |
267 | } |
268 | ||
248f219c DH |
269 | if (before_eq(seq, hard_ack)) { |
270 | ack = RXRPC_ACK_DUPLICATE; | |
271 | ack_serial = serial; | |
272 | goto skip; | |
273 | } | |
274 | ||
275 | if (flags & RXRPC_REQUEST_ACK && !ack) { | |
276 | ack = RXRPC_ACK_REQUESTED; | |
277 | ack_serial = serial; | |
278 | } | |
279 | ||
280 | if (call->rxtx_buffer[ix]) { | |
75e42126 | 281 | rxrpc_input_dup_data(call, seq, annotation, &jumbo_bad); |
248f219c DH |
282 | if (ack != RXRPC_ACK_DUPLICATE) { |
283 | ack = RXRPC_ACK_DUPLICATE; | |
284 | ack_serial = serial; | |
17926a79 | 285 | } |
248f219c DH |
286 | immediate_ack = true; |
287 | goto skip; | |
17926a79 DH |
288 | } |
289 | ||
248f219c DH |
290 | /* Queue the packet. We use a couple of memory barriers here as need |
291 | * to make sure that rx_top is perceived to be set after the buffer | |
292 | * pointer and that the buffer pointer is set after the annotation and | |
293 | * the skb data. | |
294 | * | |
295 | * Barriers against rxrpc_recvmsg_data() and rxrpc_rotate_rx_window() | |
296 | * and also rxrpc_fill_out_ack(). | |
297 | */ | |
71f3ca40 | 298 | rxrpc_get_skb(skb, rxrpc_skb_rx_got); |
248f219c DH |
299 | call->rxtx_annotations[ix] = annotation; |
300 | smp_wmb(); | |
301 | call->rxtx_buffer[ix] = skb; | |
302 | if (after(seq, call->rx_top)) | |
303 | smp_store_release(&call->rx_top, seq); | |
58dc63c9 | 304 | if (flags & RXRPC_LAST_PACKET) { |
816c9fce | 305 | set_bit(RXRPC_CALL_RX_LAST, &call->flags); |
58dc63c9 DH |
306 | trace_rxrpc_receive(call, rxrpc_receive_queue_last, serial, seq); |
307 | } else { | |
308 | trace_rxrpc_receive(call, rxrpc_receive_queue, serial, seq); | |
309 | } | |
248f219c DH |
310 | queued = true; |
311 | ||
312 | if (after_eq(seq, call->rx_expect_next)) { | |
313 | if (after(seq, call->rx_expect_next)) { | |
314 | _net("OOS %u > %u", seq, call->rx_expect_next); | |
315 | ack = RXRPC_ACK_OUT_OF_SEQUENCE; | |
316 | ack_serial = serial; | |
317 | } | |
318 | call->rx_expect_next = seq + 1; | |
17926a79 DH |
319 | } |
320 | ||
248f219c DH |
321 | skip: |
322 | offset += len; | |
323 | if (flags & RXRPC_JUMBO_PACKET) { | |
324 | if (skb_copy_bits(skb, offset, &flags, 1) < 0) | |
325 | return rxrpc_proto_abort("XJF", call, seq); | |
326 | offset += sizeof(struct rxrpc_jumbo_header); | |
327 | seq++; | |
328 | serial++; | |
329 | annotation++; | |
330 | if (flags & RXRPC_JUMBO_PACKET) | |
331 | annotation |= RXRPC_RX_ANNO_JLAST; | |
75e42126 DH |
332 | if (after(seq, hard_ack + call->rx_winsize)) { |
333 | ack = RXRPC_ACK_EXCEEDS_WINDOW; | |
334 | ack_serial = serial; | |
335 | if (!jumbo_bad) { | |
336 | call->nr_jumbo_bad++; | |
337 | jumbo_bad = true; | |
338 | } | |
339 | goto ack; | |
340 | } | |
248f219c DH |
341 | |
342 | _proto("Rx DATA Jumbo %%%u", serial); | |
343 | goto next_subpacket; | |
344 | } | |
17926a79 | 345 | |
248f219c DH |
346 | if (queued && flags & RXRPC_LAST_PACKET && !ack) { |
347 | ack = RXRPC_ACK_DELAY; | |
348 | ack_serial = serial; | |
349 | } | |
17926a79 | 350 | |
248f219c DH |
351 | ack: |
352 | if (ack) | |
353 | rxrpc_propose_ACK(call, ack, skew, ack_serial, | |
354 | immediate_ack, true); | |
17926a79 | 355 | |
248f219c DH |
356 | if (sp->hdr.seq == READ_ONCE(call->rx_hard_ack) + 1) |
357 | rxrpc_notify_socket(call); | |
358 | _leave(" [queued]"); | |
17926a79 DH |
359 | } |
360 | ||
50235c4b DH |
361 | /* |
362 | * Process a requested ACK. | |
363 | */ | |
364 | static void rxrpc_input_requested_ack(struct rxrpc_call *call, | |
365 | ktime_t resp_time, | |
366 | rxrpc_serial_t orig_serial, | |
367 | rxrpc_serial_t ack_serial) | |
368 | { | |
369 | struct rxrpc_skb_priv *sp; | |
370 | struct sk_buff *skb; | |
371 | ktime_t sent_at; | |
372 | int ix; | |
373 | ||
374 | for (ix = 0; ix < RXRPC_RXTX_BUFF_SIZE; ix++) { | |
375 | skb = call->rxtx_buffer[ix]; | |
376 | if (!skb) | |
377 | continue; | |
378 | ||
379 | sp = rxrpc_skb(skb); | |
380 | if (sp->hdr.serial != orig_serial) | |
381 | continue; | |
382 | smp_rmb(); | |
383 | sent_at = skb->tstamp; | |
384 | goto found; | |
385 | } | |
386 | return; | |
387 | ||
388 | found: | |
389 | rxrpc_peer_add_rtt(call, rxrpc_rtt_rx_requested_ack, | |
390 | orig_serial, ack_serial, sent_at, resp_time); | |
391 | } | |
392 | ||
8e83134d DH |
393 | /* |
394 | * Process a ping response. | |
395 | */ | |
396 | static void rxrpc_input_ping_response(struct rxrpc_call *call, | |
397 | ktime_t resp_time, | |
398 | rxrpc_serial_t orig_serial, | |
399 | rxrpc_serial_t ack_serial) | |
400 | { | |
401 | rxrpc_serial_t ping_serial; | |
402 | ktime_t ping_time; | |
403 | ||
404 | ping_time = call->ackr_ping_time; | |
405 | smp_rmb(); | |
406 | ping_serial = call->ackr_ping; | |
407 | ||
408 | if (!test_bit(RXRPC_CALL_PINGING, &call->flags) || | |
409 | before(orig_serial, ping_serial)) | |
410 | return; | |
411 | clear_bit(RXRPC_CALL_PINGING, &call->flags); | |
412 | if (after(orig_serial, ping_serial)) | |
413 | return; | |
414 | ||
415 | rxrpc_peer_add_rtt(call, rxrpc_rtt_rx_ping_response, | |
416 | orig_serial, ack_serial, ping_time, resp_time); | |
417 | } | |
418 | ||
17926a79 | 419 | /* |
248f219c | 420 | * Process the extra information that may be appended to an ACK packet |
17926a79 | 421 | */ |
248f219c DH |
422 | static void rxrpc_input_ackinfo(struct rxrpc_call *call, struct sk_buff *skb, |
423 | struct rxrpc_ackinfo *ackinfo) | |
17926a79 | 424 | { |
248f219c DH |
425 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); |
426 | struct rxrpc_peer *peer; | |
427 | unsigned int mtu; | |
01fd0742 | 428 | u32 rwind = ntohl(ackinfo->rwind); |
248f219c DH |
429 | |
430 | _proto("Rx ACK %%%u Info { rx=%u max=%u rwin=%u jm=%u }", | |
431 | sp->hdr.serial, | |
432 | ntohl(ackinfo->rxMTU), ntohl(ackinfo->maxMTU), | |
01fd0742 | 433 | rwind, ntohl(ackinfo->jumbo_max)); |
248f219c | 434 | |
01fd0742 DH |
435 | if (rwind > RXRPC_RXTX_BUFF_SIZE - 1) |
436 | rwind = RXRPC_RXTX_BUFF_SIZE - 1; | |
437 | call->tx_winsize = rwind; | |
248f219c DH |
438 | |
439 | mtu = min(ntohl(ackinfo->rxMTU), ntohl(ackinfo->maxMTU)); | |
440 | ||
441 | peer = call->peer; | |
442 | if (mtu < peer->maxdata) { | |
443 | spin_lock_bh(&peer->lock); | |
444 | peer->maxdata = mtu; | |
445 | peer->mtu = mtu + peer->hdrsize; | |
446 | spin_unlock_bh(&peer->lock); | |
447 | _net("Net MTU %u (maxdata %u)", peer->mtu, peer->maxdata); | |
448 | } | |
449 | } | |
17926a79 | 450 | |
248f219c DH |
451 | /* |
452 | * Process individual soft ACKs. | |
453 | * | |
454 | * Each ACK in the array corresponds to one packet and can be either an ACK or | |
455 | * a NAK. If we get find an explicitly NAK'd packet we resend immediately; | |
456 | * packets that lie beyond the end of the ACK list are scheduled for resend by | |
457 | * the timer on the basis that the peer might just not have processed them at | |
458 | * the time the ACK was sent. | |
459 | */ | |
460 | static void rxrpc_input_soft_acks(struct rxrpc_call *call, u8 *acks, | |
461 | rxrpc_seq_t seq, int nr_acks) | |
462 | { | |
463 | bool resend = false; | |
464 | int ix; | |
f07373ea | 465 | u8 annotation, anno_type; |
248f219c DH |
466 | |
467 | for (; nr_acks > 0; nr_acks--, seq++) { | |
468 | ix = seq & RXRPC_RXTX_BUFF_MASK; | |
f07373ea DH |
469 | annotation = call->rxtx_annotations[ix]; |
470 | anno_type = annotation & RXRPC_TX_ANNO_MASK; | |
471 | annotation &= ~RXRPC_TX_ANNO_MASK; | |
d01dc4c3 | 472 | switch (*acks++) { |
248f219c | 473 | case RXRPC_ACK_TYPE_ACK: |
f07373ea DH |
474 | if (anno_type == RXRPC_TX_ANNO_ACK) |
475 | continue; | |
476 | call->rxtx_annotations[ix] = | |
477 | RXRPC_TX_ANNO_ACK | annotation; | |
248f219c DH |
478 | break; |
479 | case RXRPC_ACK_TYPE_NACK: | |
f07373ea | 480 | if (anno_type == RXRPC_TX_ANNO_NAK) |
248f219c | 481 | continue; |
be8aa338 DH |
482 | if (anno_type == RXRPC_TX_ANNO_RETRANS) |
483 | continue; | |
f07373ea DH |
484 | call->rxtx_annotations[ix] = |
485 | RXRPC_TX_ANNO_NAK | annotation; | |
248f219c DH |
486 | resend = true; |
487 | break; | |
488 | default: | |
489 | return rxrpc_proto_abort("SFT", call, 0); | |
17926a79 | 490 | } |
17926a79 | 491 | } |
248f219c DH |
492 | |
493 | if (resend && | |
494 | !test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events)) | |
495 | rxrpc_queue_call(call); | |
17926a79 DH |
496 | } |
497 | ||
498 | /* | |
248f219c DH |
499 | * Process an ACK packet. |
500 | * | |
501 | * ack.firstPacket is the sequence number of the first soft-ACK'd/NAK'd packet | |
502 | * in the ACK array. Anything before that is hard-ACK'd and may be discarded. | |
503 | * | |
504 | * A hard-ACK means that a packet has been processed and may be discarded; a | |
505 | * soft-ACK means that the packet may be discarded and retransmission | |
506 | * requested. A phase is complete when all packets are hard-ACK'd. | |
17926a79 | 507 | */ |
248f219c DH |
508 | static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb, |
509 | u16 skew) | |
17926a79 DH |
510 | { |
511 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); | |
248f219c DH |
512 | union { |
513 | struct rxrpc_ackpacket ack; | |
514 | struct rxrpc_ackinfo info; | |
515 | u8 acks[RXRPC_MAXACKS]; | |
516 | } buf; | |
8e83134d | 517 | rxrpc_serial_t acked_serial; |
248f219c DH |
518 | rxrpc_seq_t first_soft_ack, hard_ack; |
519 | int nr_acks, offset; | |
520 | ||
521 | _enter(""); | |
522 | ||
523 | if (skb_copy_bits(skb, sp->offset, &buf.ack, sizeof(buf.ack)) < 0) { | |
524 | _debug("extraction failure"); | |
525 | return rxrpc_proto_abort("XAK", call, 0); | |
17926a79 | 526 | } |
248f219c DH |
527 | sp->offset += sizeof(buf.ack); |
528 | ||
8e83134d | 529 | acked_serial = ntohl(buf.ack.serial); |
248f219c DH |
530 | first_soft_ack = ntohl(buf.ack.firstPacket); |
531 | hard_ack = first_soft_ack - 1; | |
532 | nr_acks = buf.ack.nAcks; | |
533 | ||
ec71eb9a DH |
534 | trace_rxrpc_rx_ack(call, first_soft_ack, buf.ack.reason, nr_acks); |
535 | ||
248f219c DH |
536 | _proto("Rx ACK %%%u { m=%hu f=#%u p=#%u s=%%%u r=%s n=%u }", |
537 | sp->hdr.serial, | |
538 | ntohs(buf.ack.maxSkew), | |
539 | first_soft_ack, | |
540 | ntohl(buf.ack.previousPacket), | |
8e83134d | 541 | acked_serial, |
248f219c DH |
542 | rxrpc_acks(buf.ack.reason), |
543 | buf.ack.nAcks); | |
544 | ||
8e83134d DH |
545 | if (buf.ack.reason == RXRPC_ACK_PING_RESPONSE) |
546 | rxrpc_input_ping_response(call, skb->tstamp, acked_serial, | |
547 | sp->hdr.serial); | |
50235c4b DH |
548 | if (buf.ack.reason == RXRPC_ACK_REQUESTED) |
549 | rxrpc_input_requested_ack(call, skb->tstamp, acked_serial, | |
550 | sp->hdr.serial); | |
8e83134d | 551 | |
248f219c DH |
552 | if (buf.ack.reason == RXRPC_ACK_PING) { |
553 | _proto("Rx ACK %%%u PING Request", sp->hdr.serial); | |
554 | rxrpc_propose_ACK(call, RXRPC_ACK_PING_RESPONSE, | |
555 | skew, sp->hdr.serial, true, true); | |
556 | } else if (sp->hdr.flags & RXRPC_REQUEST_ACK) { | |
563ea7d5 | 557 | rxrpc_propose_ACK(call, RXRPC_ACK_REQUESTED, |
248f219c | 558 | skew, sp->hdr.serial, true, true); |
17926a79 DH |
559 | } |
560 | ||
248f219c | 561 | offset = sp->offset + nr_acks + 3; |
89a80ed4 | 562 | if (skb->len >= offset + sizeof(buf.info)) { |
248f219c DH |
563 | if (skb_copy_bits(skb, offset, &buf.info, sizeof(buf.info)) < 0) |
564 | return rxrpc_proto_abort("XAI", call, 0); | |
565 | rxrpc_input_ackinfo(call, skb, &buf.info); | |
566 | } | |
17926a79 | 567 | |
248f219c DH |
568 | if (first_soft_ack == 0) |
569 | return rxrpc_proto_abort("AK0", call, 0); | |
17926a79 | 570 | |
248f219c DH |
571 | /* Ignore ACKs unless we are or have just been transmitting. */ |
572 | switch (call->state) { | |
573 | case RXRPC_CALL_CLIENT_SEND_REQUEST: | |
574 | case RXRPC_CALL_CLIENT_AWAIT_REPLY: | |
575 | case RXRPC_CALL_SERVER_SEND_REPLY: | |
576 | case RXRPC_CALL_SERVER_AWAIT_ACK: | |
577 | break; | |
17926a79 | 578 | default: |
248f219c DH |
579 | return; |
580 | } | |
17926a79 | 581 | |
248f219c | 582 | /* Discard any out-of-order or duplicate ACKs. */ |
98dafac5 | 583 | if (before_eq(sp->hdr.serial, call->acks_latest)) { |
248f219c DH |
584 | _debug("discard ACK %d <= %d", |
585 | sp->hdr.serial, call->acks_latest); | |
586 | return; | |
587 | } | |
588 | call->acks_latest = sp->hdr.serial; | |
17926a79 | 589 | |
248f219c DH |
590 | if (test_bit(RXRPC_CALL_TX_LAST, &call->flags) && |
591 | hard_ack == call->tx_top) { | |
592 | rxrpc_end_tx_phase(call, "ETA"); | |
593 | return; | |
594 | } | |
17926a79 | 595 | |
248f219c DH |
596 | if (before(hard_ack, call->tx_hard_ack) || |
597 | after(hard_ack, call->tx_top)) | |
598 | return rxrpc_proto_abort("AKW", call, 0); | |
17926a79 | 599 | |
248f219c DH |
600 | if (after(hard_ack, call->tx_hard_ack)) |
601 | rxrpc_rotate_tx_window(call, hard_ack); | |
17926a79 | 602 | |
248f219c DH |
603 | if (after(first_soft_ack, call->tx_top)) |
604 | return; | |
17926a79 | 605 | |
248f219c DH |
606 | if (nr_acks > call->tx_top - first_soft_ack + 1) |
607 | nr_acks = first_soft_ack - call->tx_top + 1; | |
608 | if (skb_copy_bits(skb, sp->offset, buf.acks, nr_acks) < 0) | |
609 | return rxrpc_proto_abort("XSA", call, 0); | |
610 | rxrpc_input_soft_acks(call, buf.acks, first_soft_ack, nr_acks); | |
17926a79 DH |
611 | } |
612 | ||
613 | /* | |
248f219c | 614 | * Process an ACKALL packet. |
17926a79 | 615 | */ |
248f219c | 616 | static void rxrpc_input_ackall(struct rxrpc_call *call, struct sk_buff *skb) |
17926a79 | 617 | { |
248f219c | 618 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); |
17926a79 | 619 | |
248f219c | 620 | _proto("Rx ACKALL %%%u", sp->hdr.serial); |
17926a79 | 621 | |
248f219c DH |
622 | rxrpc_end_tx_phase(call, "ETL"); |
623 | } | |
17926a79 | 624 | |
248f219c DH |
625 | /* |
626 | * Process an ABORT packet. | |
627 | */ | |
628 | static void rxrpc_input_abort(struct rxrpc_call *call, struct sk_buff *skb) | |
629 | { | |
630 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); | |
631 | __be32 wtmp; | |
632 | u32 abort_code = RX_CALL_DEAD; | |
17926a79 | 633 | |
248f219c | 634 | _enter(""); |
17926a79 | 635 | |
248f219c DH |
636 | if (skb->len >= 4 && |
637 | skb_copy_bits(skb, sp->offset, &wtmp, sizeof(wtmp)) >= 0) | |
638 | abort_code = ntohl(wtmp); | |
17926a79 | 639 | |
248f219c | 640 | _proto("Rx ABORT %%%u { %x }", sp->hdr.serial, abort_code); |
17926a79 | 641 | |
248f219c DH |
642 | if (rxrpc_set_call_completion(call, RXRPC_CALL_REMOTELY_ABORTED, |
643 | abort_code, ECONNABORTED)) | |
644 | rxrpc_notify_socket(call); | |
17926a79 DH |
645 | } |
646 | ||
647 | /* | |
248f219c | 648 | * Process an incoming call packet. |
17926a79 | 649 | */ |
248f219c DH |
650 | static void rxrpc_input_call_packet(struct rxrpc_call *call, |
651 | struct sk_buff *skb, u16 skew) | |
17926a79 | 652 | { |
248f219c | 653 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); |
17926a79 | 654 | |
7727640c | 655 | _enter("%p,%p", call, skb); |
17926a79 | 656 | |
248f219c DH |
657 | switch (sp->hdr.type) { |
658 | case RXRPC_PACKET_TYPE_DATA: | |
659 | rxrpc_input_data(call, skb, skew); | |
660 | break; | |
f5c17aae | 661 | |
248f219c DH |
662 | case RXRPC_PACKET_TYPE_ACK: |
663 | rxrpc_input_ack(call, skb, skew); | |
17926a79 | 664 | break; |
17926a79 | 665 | |
248f219c DH |
666 | case RXRPC_PACKET_TYPE_BUSY: |
667 | _proto("Rx BUSY %%%u", sp->hdr.serial); | |
17926a79 | 668 | |
248f219c DH |
669 | /* Just ignore BUSY packets from the server; the retry and |
670 | * lifespan timers will take care of business. BUSY packets | |
671 | * from the client don't make sense. | |
672 | */ | |
673 | break; | |
17926a79 | 674 | |
248f219c DH |
675 | case RXRPC_PACKET_TYPE_ABORT: |
676 | rxrpc_input_abort(call, skb); | |
677 | break; | |
17926a79 | 678 | |
248f219c DH |
679 | case RXRPC_PACKET_TYPE_ACKALL: |
680 | rxrpc_input_ackall(call, skb); | |
681 | break; | |
f5c17aae | 682 | |
248f219c DH |
683 | default: |
684 | _proto("Rx %s %%%u", rxrpc_pkts[sp->hdr.type], sp->hdr.serial); | |
685 | break; | |
17926a79 | 686 | } |
248f219c | 687 | |
17926a79 DH |
688 | _leave(""); |
689 | } | |
690 | ||
691 | /* | |
692 | * post connection-level events to the connection | |
18bfeba5 DH |
693 | * - this includes challenges, responses, some aborts and call terminal packet |
694 | * retransmission. | |
17926a79 | 695 | */ |
2e7e9758 | 696 | static void rxrpc_post_packet_to_conn(struct rxrpc_connection *conn, |
17926a79 DH |
697 | struct sk_buff *skb) |
698 | { | |
699 | _enter("%p,%p", conn, skb); | |
700 | ||
17926a79 | 701 | skb_queue_tail(&conn->rx_queue, skb); |
2e7e9758 | 702 | rxrpc_queue_conn(conn); |
17926a79 DH |
703 | } |
704 | ||
44ba0698 DH |
705 | /* |
706 | * post endpoint-level events to the local endpoint | |
707 | * - this includes debug and version messages | |
708 | */ | |
709 | static void rxrpc_post_packet_to_local(struct rxrpc_local *local, | |
710 | struct sk_buff *skb) | |
711 | { | |
712 | _enter("%p,%p", local, skb); | |
713 | ||
44ba0698 | 714 | skb_queue_tail(&local->event_queue, skb); |
5acbee46 | 715 | rxrpc_queue_local(local); |
44ba0698 DH |
716 | } |
717 | ||
248f219c DH |
718 | /* |
719 | * put a packet up for transport-level abort | |
720 | */ | |
721 | static void rxrpc_reject_packet(struct rxrpc_local *local, struct sk_buff *skb) | |
722 | { | |
723 | CHECK_SLAB_OKAY(&local->usage); | |
724 | ||
725 | skb_queue_tail(&local->reject_queue, skb); | |
726 | rxrpc_queue_local(local); | |
727 | } | |
728 | ||
0d12f8a4 DH |
729 | /* |
730 | * Extract the wire header from a packet and translate the byte order. | |
731 | */ | |
732 | static noinline | |
733 | int rxrpc_extract_header(struct rxrpc_skb_priv *sp, struct sk_buff *skb) | |
734 | { | |
735 | struct rxrpc_wire_header whdr; | |
736 | ||
737 | /* dig out the RxRPC connection details */ | |
4d0fc73e | 738 | if (skb_copy_bits(skb, 0, &whdr, sizeof(whdr)) < 0) |
0d12f8a4 | 739 | return -EBADMSG; |
0d12f8a4 DH |
740 | |
741 | memset(sp, 0, sizeof(*sp)); | |
742 | sp->hdr.epoch = ntohl(whdr.epoch); | |
743 | sp->hdr.cid = ntohl(whdr.cid); | |
744 | sp->hdr.callNumber = ntohl(whdr.callNumber); | |
745 | sp->hdr.seq = ntohl(whdr.seq); | |
746 | sp->hdr.serial = ntohl(whdr.serial); | |
747 | sp->hdr.flags = whdr.flags; | |
748 | sp->hdr.type = whdr.type; | |
749 | sp->hdr.userStatus = whdr.userStatus; | |
750 | sp->hdr.securityIndex = whdr.securityIndex; | |
751 | sp->hdr._rsvd = ntohs(whdr._rsvd); | |
752 | sp->hdr.serviceId = ntohs(whdr.serviceId); | |
248f219c | 753 | sp->offset = sizeof(whdr); |
0d12f8a4 DH |
754 | return 0; |
755 | } | |
756 | ||
17926a79 DH |
757 | /* |
758 | * handle data received on the local endpoint | |
759 | * - may be called in interrupt context | |
4f95dd78 DH |
760 | * |
761 | * The socket is locked by the caller and this prevents the socket from being | |
762 | * shut down and the local endpoint from going away, thus sk_user_data will not | |
763 | * be cleared until this function returns. | |
17926a79 | 764 | */ |
248f219c | 765 | void rxrpc_data_ready(struct sock *udp_sk) |
17926a79 | 766 | { |
8496af50 | 767 | struct rxrpc_connection *conn; |
248f219c DH |
768 | struct rxrpc_channel *chan; |
769 | struct rxrpc_call *call; | |
17926a79 | 770 | struct rxrpc_skb_priv *sp; |
248f219c | 771 | struct rxrpc_local *local = udp_sk->sk_user_data; |
17926a79 | 772 | struct sk_buff *skb; |
248f219c | 773 | unsigned int channel; |
563ea7d5 | 774 | int ret, skew; |
17926a79 | 775 | |
248f219c | 776 | _enter("%p", udp_sk); |
17926a79 DH |
777 | |
778 | ASSERT(!irqs_disabled()); | |
779 | ||
248f219c | 780 | skb = skb_recv_datagram(udp_sk, 0, 1, &ret); |
17926a79 | 781 | if (!skb) { |
17926a79 DH |
782 | if (ret == -EAGAIN) |
783 | return; | |
784 | _debug("UDP socket error %d", ret); | |
785 | return; | |
786 | } | |
787 | ||
71f3ca40 | 788 | rxrpc_new_skb(skb, rxrpc_skb_rx_received); |
17926a79 DH |
789 | |
790 | _net("recv skb %p", skb); | |
791 | ||
792 | /* we'll probably need to checksum it (didn't call sock_recvmsg) */ | |
793 | if (skb_checksum_complete(skb)) { | |
71f3ca40 | 794 | rxrpc_free_skb(skb, rxrpc_skb_rx_freed); |
02c22347 | 795 | __UDP_INC_STATS(&init_net, UDP_MIB_INERRORS, 0); |
17926a79 DH |
796 | _leave(" [CSUM failed]"); |
797 | return; | |
798 | } | |
799 | ||
02c22347 | 800 | __UDP_INC_STATS(&init_net, UDP_MIB_INDATAGRAMS, 0); |
1781f7f5 | 801 | |
0d12f8a4 DH |
802 | /* The socket buffer we have is owned by UDP, with UDP's data all over |
803 | * it, but we really want our own data there. | |
804 | */ | |
17926a79 DH |
805 | skb_orphan(skb); |
806 | sp = rxrpc_skb(skb); | |
17926a79 | 807 | |
8a681c36 DH |
808 | if (IS_ENABLED(CONFIG_AF_RXRPC_INJECT_LOSS)) { |
809 | static int lose; | |
810 | if ((lose++ & 7) == 7) { | |
811 | rxrpc_lose_skb(skb, rxrpc_skb_rx_lost); | |
812 | return; | |
813 | } | |
814 | } | |
815 | ||
17926a79 DH |
816 | _net("Rx UDP packet from %08x:%04hu", |
817 | ntohl(ip_hdr(skb)->saddr), ntohs(udp_hdr(skb)->source)); | |
818 | ||
819 | /* dig out the RxRPC connection details */ | |
0d12f8a4 | 820 | if (rxrpc_extract_header(sp, skb) < 0) |
17926a79 | 821 | goto bad_message; |
49e19ec7 | 822 | trace_rxrpc_rx_packet(sp); |
17926a79 DH |
823 | |
824 | _net("Rx RxRPC %s ep=%x call=%x:%x", | |
825 | sp->hdr.flags & RXRPC_CLIENT_INITIATED ? "ToServer" : "ToClient", | |
0d12f8a4 | 826 | sp->hdr.epoch, sp->hdr.cid, sp->hdr.callNumber); |
17926a79 | 827 | |
351c1e64 DH |
828 | if (sp->hdr.type >= RXRPC_N_PACKET_TYPES || |
829 | !((RXRPC_SUPPORTED_PACKET_TYPES >> sp->hdr.type) & 1)) { | |
17926a79 DH |
830 | _proto("Rx Bad Packet Type %u", sp->hdr.type); |
831 | goto bad_message; | |
832 | } | |
833 | ||
248f219c DH |
834 | switch (sp->hdr.type) { |
835 | case RXRPC_PACKET_TYPE_VERSION: | |
44ba0698 DH |
836 | rxrpc_post_packet_to_local(local, skb); |
837 | goto out; | |
bc6e1ea3 | 838 | |
248f219c DH |
839 | case RXRPC_PACKET_TYPE_BUSY: |
840 | if (sp->hdr.flags & RXRPC_CLIENT_INITIATED) | |
841 | goto discard; | |
842 | ||
843 | case RXRPC_PACKET_TYPE_DATA: | |
844 | if (sp->hdr.callNumber == 0) | |
845 | goto bad_message; | |
846 | if (sp->hdr.flags & RXRPC_JUMBO_PACKET && | |
847 | !rxrpc_validate_jumbo(skb)) | |
848 | goto bad_message; | |
849 | break; | |
850 | } | |
17926a79 | 851 | |
8496af50 DH |
852 | rcu_read_lock(); |
853 | ||
8496af50 | 854 | conn = rxrpc_find_connection_rcu(local, skb); |
248f219c DH |
855 | if (conn) { |
856 | if (sp->hdr.securityIndex != conn->security_ix) | |
857 | goto wrong_security; | |
563ea7d5 | 858 | |
248f219c DH |
859 | if (sp->hdr.callNumber == 0) { |
860 | /* Connection-level packet */ | |
861 | _debug("CONN %p {%d}", conn, conn->debug_id); | |
862 | rxrpc_post_packet_to_conn(conn, skb); | |
863 | goto out_unlock; | |
864 | } | |
865 | ||
866 | /* Note the serial number skew here */ | |
867 | skew = (int)sp->hdr.serial - (int)conn->hi_serial; | |
868 | if (skew >= 0) { | |
869 | if (skew > 0) | |
870 | conn->hi_serial = sp->hdr.serial; | |
871 | } else { | |
872 | skew = -skew; | |
873 | skew = min(skew, 65535); | |
874 | } | |
17926a79 | 875 | |
8496af50 | 876 | /* Call-bound packets are routed by connection channel. */ |
248f219c DH |
877 | channel = sp->hdr.cid & RXRPC_CHANNELMASK; |
878 | chan = &conn->channels[channel]; | |
18bfeba5 DH |
879 | |
880 | /* Ignore really old calls */ | |
881 | if (sp->hdr.callNumber < chan->last_call) | |
882 | goto discard_unlock; | |
883 | ||
884 | if (sp->hdr.callNumber == chan->last_call) { | |
248f219c DH |
885 | /* For the previous service call, if completed successfully, we |
886 | * discard all further packets. | |
18bfeba5 | 887 | */ |
2266ffde | 888 | if (rxrpc_conn_is_service(conn) && |
18bfeba5 DH |
889 | (chan->last_type == RXRPC_PACKET_TYPE_ACK || |
890 | sp->hdr.type == RXRPC_PACKET_TYPE_ABORT)) | |
891 | goto discard_unlock; | |
892 | ||
248f219c DH |
893 | /* But otherwise we need to retransmit the final packet from |
894 | * data cached in the connection record. | |
18bfeba5 DH |
895 | */ |
896 | rxrpc_post_packet_to_conn(conn, skb); | |
897 | goto out_unlock; | |
898 | } | |
0d12f8a4 | 899 | |
18bfeba5 | 900 | call = rcu_dereference(chan->call); |
248f219c DH |
901 | } else { |
902 | skew = 0; | |
903 | call = NULL; | |
904 | } | |
8496af50 | 905 | |
248f219c DH |
906 | if (!call || atomic_read(&call->usage) == 0) { |
907 | if (!(sp->hdr.type & RXRPC_CLIENT_INITIATED) || | |
908 | sp->hdr.callNumber == 0 || | |
909 | sp->hdr.type != RXRPC_PACKET_TYPE_DATA) | |
910 | goto bad_message_unlock; | |
911 | if (sp->hdr.seq != 1) | |
912 | goto discard_unlock; | |
913 | call = rxrpc_new_incoming_call(local, conn, skb); | |
914 | if (!call) { | |
915 | rcu_read_unlock(); | |
916 | goto reject_packet; | |
917 | } | |
8e83134d | 918 | rxrpc_send_ping(call, skb, skew); |
7727640c | 919 | } |
44ba0698 | 920 | |
248f219c DH |
921 | rxrpc_input_call_packet(call, skb, skew); |
922 | goto discard_unlock; | |
923 | ||
18bfeba5 | 924 | discard_unlock: |
8496af50 | 925 | rcu_read_unlock(); |
248f219c | 926 | discard: |
71f3ca40 | 927 | rxrpc_free_skb(skb, rxrpc_skb_rx_freed); |
44ba0698 | 928 | out: |
49e19ec7 | 929 | trace_rxrpc_rx_done(0, 0); |
17926a79 DH |
930 | return; |
931 | ||
248f219c | 932 | out_unlock: |
8496af50 | 933 | rcu_read_unlock(); |
248f219c | 934 | goto out; |
8496af50 | 935 | |
248f219c DH |
936 | wrong_security: |
937 | rcu_read_unlock(); | |
938 | trace_rxrpc_abort("SEC", sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq, | |
939 | RXKADINCONSISTENCY, EBADMSG); | |
940 | skb->priority = RXKADINCONSISTENCY; | |
941 | goto post_abort; | |
17926a79 | 942 | |
248f219c DH |
943 | bad_message_unlock: |
944 | rcu_read_unlock(); | |
17926a79 | 945 | bad_message: |
248f219c DH |
946 | trace_rxrpc_abort("BAD", sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq, |
947 | RX_PROTOCOL_ERROR, EBADMSG); | |
17926a79 | 948 | skb->priority = RX_PROTOCOL_ERROR; |
248f219c DH |
949 | post_abort: |
950 | skb->mark = RXRPC_SKB_MARK_LOCAL_ABORT; | |
49e19ec7 DH |
951 | reject_packet: |
952 | trace_rxrpc_rx_done(skb->mark, skb->priority); | |
17926a79 | 953 | rxrpc_reject_packet(local, skb); |
17926a79 DH |
954 | _leave(" [badmsg]"); |
955 | } |