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Commit | Line | Data |
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17926a79 DH |
1 | /* RxRPC recvmsg() implementation |
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 | ||
9b6d5398 JP |
12 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
13 | ||
17926a79 DH |
14 | #include <linux/net.h> |
15 | #include <linux/skbuff.h> | |
bc3b2d7f | 16 | #include <linux/export.h> |
174cd4b1 IM |
17 | #include <linux/sched/signal.h> |
18 | ||
17926a79 DH |
19 | #include <net/sock.h> |
20 | #include <net/af_rxrpc.h> | |
21 | #include "ar-internal.h" | |
22 | ||
17926a79 | 23 | /* |
248f219c DH |
24 | * Post a call for attention by the socket or kernel service. Further |
25 | * notifications are suppressed by putting recvmsg_link on a dummy queue. | |
17926a79 | 26 | */ |
248f219c | 27 | void rxrpc_notify_socket(struct rxrpc_call *call) |
17926a79 | 28 | { |
248f219c DH |
29 | struct rxrpc_sock *rx; |
30 | struct sock *sk; | |
17926a79 | 31 | |
248f219c | 32 | _enter("%d", call->debug_id); |
17926a79 | 33 | |
248f219c DH |
34 | if (!list_empty(&call->recvmsg_link)) |
35 | return; | |
36 | ||
37 | rcu_read_lock(); | |
38 | ||
39 | rx = rcu_dereference(call->socket); | |
40 | sk = &rx->sk; | |
41 | if (rx && sk->sk_state < RXRPC_CLOSE) { | |
42 | if (call->notify_rx) { | |
43 | call->notify_rx(sk, call, call->user_call_ID); | |
44 | } else { | |
45 | write_lock_bh(&rx->recvmsg_lock); | |
46 | if (list_empty(&call->recvmsg_link)) { | |
47 | rxrpc_get_call(call, rxrpc_call_got); | |
48 | list_add_tail(&call->recvmsg_link, &rx->recvmsg_q); | |
49 | } | |
50 | write_unlock_bh(&rx->recvmsg_lock); | |
17926a79 | 51 | |
248f219c DH |
52 | if (!sock_flag(sk, SOCK_DEAD)) { |
53 | _debug("call %ps", sk->sk_data_ready); | |
54 | sk->sk_data_ready(sk); | |
55 | } | |
56 | } | |
57 | } | |
17926a79 | 58 | |
248f219c DH |
59 | rcu_read_unlock(); |
60 | _leave(""); | |
61 | } | |
17926a79 | 62 | |
248f219c DH |
63 | /* |
64 | * Pass a call terminating message to userspace. | |
65 | */ | |
66 | static int rxrpc_recvmsg_term(struct rxrpc_call *call, struct msghdr *msg) | |
67 | { | |
68 | u32 tmp = 0; | |
69 | int ret; | |
17926a79 | 70 | |
248f219c DH |
71 | switch (call->completion) { |
72 | case RXRPC_CALL_SUCCEEDED: | |
73 | ret = 0; | |
74 | if (rxrpc_is_service_call(call)) | |
75 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ACK, 0, &tmp); | |
76 | break; | |
77 | case RXRPC_CALL_REMOTELY_ABORTED: | |
78 | tmp = call->abort_code; | |
79 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ABORT, 4, &tmp); | |
80 | break; | |
81 | case RXRPC_CALL_LOCALLY_ABORTED: | |
82 | tmp = call->abort_code; | |
83 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ABORT, 4, &tmp); | |
84 | break; | |
85 | case RXRPC_CALL_NETWORK_ERROR: | |
86 | tmp = call->error; | |
87 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_NET_ERROR, 4, &tmp); | |
88 | break; | |
89 | case RXRPC_CALL_LOCAL_ERROR: | |
90 | tmp = call->error; | |
91 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_LOCAL_ERROR, 4, &tmp); | |
92 | break; | |
93 | default: | |
94 | pr_err("Invalid terminal call state %u\n", call->state); | |
95 | BUG(); | |
96 | break; | |
97 | } | |
17926a79 | 98 | |
84997905 DH |
99 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_terminal, call->rx_hard_ack, |
100 | call->rx_pkt_offset, call->rx_pkt_len, ret); | |
248f219c DH |
101 | return ret; |
102 | } | |
17926a79 | 103 | |
248f219c DH |
104 | /* |
105 | * Pass back notification of a new call. The call is added to the | |
106 | * to-be-accepted list. This means that the next call to be accepted might not | |
107 | * be the last call seen awaiting acceptance, but unless we leave this on the | |
108 | * front of the queue and block all other messages until someone gives us a | |
109 | * user_ID for it, there's not a lot we can do. | |
110 | */ | |
111 | static int rxrpc_recvmsg_new_call(struct rxrpc_sock *rx, | |
112 | struct rxrpc_call *call, | |
113 | struct msghdr *msg, int flags) | |
114 | { | |
115 | int tmp = 0, ret; | |
17926a79 | 116 | |
248f219c | 117 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_NEW_CALL, 0, &tmp); |
17926a79 | 118 | |
248f219c DH |
119 | if (ret == 0 && !(flags & MSG_PEEK)) { |
120 | _debug("to be accepted"); | |
121 | write_lock_bh(&rx->recvmsg_lock); | |
122 | list_del_init(&call->recvmsg_link); | |
123 | write_unlock_bh(&rx->recvmsg_lock); | |
17926a79 | 124 | |
3432a757 | 125 | rxrpc_get_call(call, rxrpc_call_got); |
248f219c DH |
126 | write_lock(&rx->call_lock); |
127 | list_add_tail(&call->accept_link, &rx->to_be_accepted); | |
128 | write_unlock(&rx->call_lock); | |
129 | } | |
17926a79 | 130 | |
84997905 | 131 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_to_be_accepted, 1, 0, 0, ret); |
248f219c DH |
132 | return ret; |
133 | } | |
17926a79 | 134 | |
248f219c DH |
135 | /* |
136 | * End the packet reception phase. | |
137 | */ | |
b69d94d7 | 138 | static void rxrpc_end_rx_phase(struct rxrpc_call *call, rxrpc_serial_t serial) |
248f219c DH |
139 | { |
140 | _enter("%d,%s", call->debug_id, rxrpc_call_states[call->state]); | |
17926a79 | 141 | |
58dc63c9 | 142 | trace_rxrpc_receive(call, rxrpc_receive_end, 0, call->rx_top); |
816c9fce DH |
143 | ASSERTCMP(call->rx_hard_ack, ==, call->rx_top); |
144 | ||
248f219c | 145 | if (call->state == RXRPC_CALL_CLIENT_RECV_REPLY) { |
b69d94d7 | 146 | rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, 0, serial, true, false, |
9c7ad434 | 147 | rxrpc_propose_ack_terminal_ack); |
a5af7e1f | 148 | rxrpc_send_ack_packet(call, false); |
248f219c | 149 | } |
17926a79 | 150 | |
248f219c | 151 | write_lock_bh(&call->state_lock); |
17926a79 | 152 | |
248f219c DH |
153 | switch (call->state) { |
154 | case RXRPC_CALL_CLIENT_RECV_REPLY: | |
155 | __rxrpc_call_completed(call); | |
9749fd2b | 156 | write_unlock_bh(&call->state_lock); |
248f219c | 157 | break; |
17926a79 | 158 | |
248f219c | 159 | case RXRPC_CALL_SERVER_RECV_REQUEST: |
71f3ca40 | 160 | call->tx_phase = true; |
248f219c | 161 | call->state = RXRPC_CALL_SERVER_ACK_REQUEST; |
9749fd2b DH |
162 | call->ack_at = call->expire_at; |
163 | write_unlock_bh(&call->state_lock); | |
164 | rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial, false, true, | |
165 | rxrpc_propose_ack_processing_op); | |
248f219c DH |
166 | break; |
167 | default: | |
9749fd2b | 168 | write_unlock_bh(&call->state_lock); |
248f219c DH |
169 | break; |
170 | } | |
248f219c | 171 | } |
17926a79 | 172 | |
248f219c DH |
173 | /* |
174 | * Discard a packet we've used up and advance the Rx window by one. | |
175 | */ | |
176 | static void rxrpc_rotate_rx_window(struct rxrpc_call *call) | |
177 | { | |
816c9fce | 178 | struct rxrpc_skb_priv *sp; |
248f219c | 179 | struct sk_buff *skb; |
58dc63c9 | 180 | rxrpc_serial_t serial; |
248f219c | 181 | rxrpc_seq_t hard_ack, top; |
816c9fce | 182 | u8 flags; |
248f219c DH |
183 | int ix; |
184 | ||
185 | _enter("%d", call->debug_id); | |
186 | ||
187 | hard_ack = call->rx_hard_ack; | |
188 | top = smp_load_acquire(&call->rx_top); | |
189 | ASSERT(before(hard_ack, top)); | |
190 | ||
191 | hard_ack++; | |
192 | ix = hard_ack & RXRPC_RXTX_BUFF_MASK; | |
193 | skb = call->rxtx_buffer[ix]; | |
71f3ca40 | 194 | rxrpc_see_skb(skb, rxrpc_skb_rx_rotated); |
816c9fce DH |
195 | sp = rxrpc_skb(skb); |
196 | flags = sp->hdr.flags; | |
58dc63c9 DH |
197 | serial = sp->hdr.serial; |
198 | if (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO) | |
199 | serial += (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO) - 1; | |
200 | ||
248f219c DH |
201 | call->rxtx_buffer[ix] = NULL; |
202 | call->rxtx_annotations[ix] = 0; | |
203 | /* Barrier against rxrpc_input_data(). */ | |
204 | smp_store_release(&call->rx_hard_ack, hard_ack); | |
17926a79 | 205 | |
71f3ca40 | 206 | rxrpc_free_skb(skb, rxrpc_skb_rx_freed); |
17926a79 | 207 | |
816c9fce | 208 | _debug("%u,%u,%02x", hard_ack, top, flags); |
58dc63c9 | 209 | trace_rxrpc_receive(call, rxrpc_receive_rotate, serial, hard_ack); |
805b21b9 | 210 | if (flags & RXRPC_LAST_PACKET) { |
b69d94d7 | 211 | rxrpc_end_rx_phase(call, serial); |
805b21b9 DH |
212 | } else { |
213 | /* Check to see if there's an ACK that needs sending. */ | |
214 | if (after_eq(hard_ack, call->ackr_consumed + 2) || | |
215 | after_eq(top, call->ackr_seen + 2) || | |
216 | (hard_ack == top && after(hard_ack, call->ackr_consumed))) | |
217 | rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial, | |
218 | true, false, | |
219 | rxrpc_propose_ack_rotate_rx); | |
220 | if (call->ackr_reason) | |
a5af7e1f | 221 | rxrpc_send_ack_packet(call, false); |
805b21b9 | 222 | } |
248f219c DH |
223 | } |
224 | ||
225 | /* | |
226 | * Decrypt and verify a (sub)packet. The packet's length may be changed due to | |
227 | * padding, but if this is the case, the packet length will be resident in the | |
228 | * socket buffer. Note that we can't modify the master skb info as the skb may | |
229 | * be the home to multiple subpackets. | |
230 | */ | |
231 | static int rxrpc_verify_packet(struct rxrpc_call *call, struct sk_buff *skb, | |
232 | u8 annotation, | |
233 | unsigned int offset, unsigned int len) | |
234 | { | |
235 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); | |
236 | rxrpc_seq_t seq = sp->hdr.seq; | |
237 | u16 cksum = sp->hdr.cksum; | |
238 | ||
239 | _enter(""); | |
240 | ||
241 | /* For all but the head jumbo subpacket, the security checksum is in a | |
242 | * jumbo header immediately prior to the data. | |
243 | */ | |
244 | if ((annotation & RXRPC_RX_ANNO_JUMBO) > 1) { | |
245 | __be16 tmp; | |
246 | if (skb_copy_bits(skb, offset - 2, &tmp, 2) < 0) | |
247 | BUG(); | |
248 | cksum = ntohs(tmp); | |
249 | seq += (annotation & RXRPC_RX_ANNO_JUMBO) - 1; | |
250 | } | |
251 | ||
252 | return call->conn->security->verify_packet(call, skb, offset, len, | |
253 | seq, cksum); | |
254 | } | |
255 | ||
256 | /* | |
257 | * Locate the data within a packet. This is complicated by: | |
258 | * | |
259 | * (1) An skb may contain a jumbo packet - so we have to find the appropriate | |
260 | * subpacket. | |
261 | * | |
262 | * (2) The (sub)packets may be encrypted and, if so, the encrypted portion | |
263 | * contains an extra header which includes the true length of the data, | |
264 | * excluding any encrypted padding. | |
265 | */ | |
266 | static int rxrpc_locate_data(struct rxrpc_call *call, struct sk_buff *skb, | |
267 | u8 *_annotation, | |
268 | unsigned int *_offset, unsigned int *_len) | |
269 | { | |
775e5b71 | 270 | unsigned int offset = sizeof(struct rxrpc_wire_header); |
248f219c DH |
271 | unsigned int len = *_len; |
272 | int ret; | |
273 | u8 annotation = *_annotation; | |
274 | ||
248f219c | 275 | /* Locate the subpacket */ |
775e5b71 | 276 | len = skb->len - offset; |
248f219c DH |
277 | if ((annotation & RXRPC_RX_ANNO_JUMBO) > 0) { |
278 | offset += (((annotation & RXRPC_RX_ANNO_JUMBO) - 1) * | |
279 | RXRPC_JUMBO_SUBPKTLEN); | |
280 | len = (annotation & RXRPC_RX_ANNO_JLAST) ? | |
281 | skb->len - offset : RXRPC_JUMBO_SUBPKTLEN; | |
282 | } | |
283 | ||
284 | if (!(annotation & RXRPC_RX_ANNO_VERIFIED)) { | |
285 | ret = rxrpc_verify_packet(call, skb, annotation, offset, len); | |
17926a79 | 286 | if (ret < 0) |
248f219c DH |
287 | return ret; |
288 | *_annotation |= RXRPC_RX_ANNO_VERIFIED; | |
289 | } | |
17926a79 | 290 | |
248f219c DH |
291 | *_offset = offset; |
292 | *_len = len; | |
293 | call->conn->security->locate_data(call, skb, _offset, _len); | |
294 | return 0; | |
295 | } | |
17926a79 | 296 | |
248f219c DH |
297 | /* |
298 | * Deliver messages to a call. This keeps processing packets until the buffer | |
299 | * is filled and we find either more DATA (returns 0) or the end of the DATA | |
300 | * (returns 1). If more packets are required, it returns -EAGAIN. | |
301 | */ | |
302 | static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call, | |
303 | struct msghdr *msg, struct iov_iter *iter, | |
304 | size_t len, int flags, size_t *_offset) | |
305 | { | |
306 | struct rxrpc_skb_priv *sp; | |
307 | struct sk_buff *skb; | |
308 | rxrpc_seq_t hard_ack, top, seq; | |
309 | size_t remain; | |
310 | bool last; | |
311 | unsigned int rx_pkt_offset, rx_pkt_len; | |
816c9fce | 312 | int ix, copy, ret = -EAGAIN, ret2; |
248f219c | 313 | |
248f219c DH |
314 | rx_pkt_offset = call->rx_pkt_offset; |
315 | rx_pkt_len = call->rx_pkt_len; | |
316 | ||
816c9fce DH |
317 | if (call->state >= RXRPC_CALL_SERVER_ACK_REQUEST) { |
318 | seq = call->rx_hard_ack; | |
319 | ret = 1; | |
320 | goto done; | |
321 | } | |
322 | ||
248f219c DH |
323 | /* Barriers against rxrpc_input_data(). */ |
324 | hard_ack = call->rx_hard_ack; | |
d7e15835 DH |
325 | seq = hard_ack + 1; |
326 | while (top = smp_load_acquire(&call->rx_top), | |
327 | before_eq(seq, top) | |
328 | ) { | |
248f219c DH |
329 | ix = seq & RXRPC_RXTX_BUFF_MASK; |
330 | skb = call->rxtx_buffer[ix]; | |
84997905 DH |
331 | if (!skb) { |
332 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_hole, seq, | |
333 | rx_pkt_offset, rx_pkt_len, 0); | |
248f219c | 334 | break; |
84997905 | 335 | } |
248f219c | 336 | smp_rmb(); |
71f3ca40 | 337 | rxrpc_see_skb(skb, rxrpc_skb_rx_seen); |
248f219c | 338 | sp = rxrpc_skb(skb); |
17926a79 | 339 | |
58dc63c9 DH |
340 | if (!(flags & MSG_PEEK)) |
341 | trace_rxrpc_receive(call, rxrpc_receive_front, | |
342 | sp->hdr.serial, seq); | |
343 | ||
248f219c DH |
344 | if (msg) |
345 | sock_recv_timestamp(msg, sock->sk, skb); | |
346 | ||
2e2ea51d | 347 | if (rx_pkt_offset == 0) { |
816c9fce DH |
348 | ret2 = rxrpc_locate_data(call, skb, |
349 | &call->rxtx_annotations[ix], | |
350 | &rx_pkt_offset, &rx_pkt_len); | |
84997905 DH |
351 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_next, seq, |
352 | rx_pkt_offset, rx_pkt_len, ret2); | |
816c9fce DH |
353 | if (ret2 < 0) { |
354 | ret = ret2; | |
2e2ea51d | 355 | goto out; |
816c9fce | 356 | } |
84997905 DH |
357 | } else { |
358 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_cont, seq, | |
359 | rx_pkt_offset, rx_pkt_len, 0); | |
2e2ea51d | 360 | } |
248f219c DH |
361 | |
362 | /* We have to handle short, empty and used-up DATA packets. */ | |
363 | remain = len - *_offset; | |
364 | copy = rx_pkt_len; | |
365 | if (copy > remain) | |
366 | copy = remain; | |
367 | if (copy > 0) { | |
816c9fce DH |
368 | ret2 = skb_copy_datagram_iter(skb, rx_pkt_offset, iter, |
369 | copy); | |
370 | if (ret2 < 0) { | |
371 | ret = ret2; | |
248f219c | 372 | goto out; |
816c9fce | 373 | } |
248f219c DH |
374 | |
375 | /* handle piecemeal consumption of data packets */ | |
248f219c DH |
376 | rx_pkt_offset += copy; |
377 | rx_pkt_len -= copy; | |
378 | *_offset += copy; | |
379 | } | |
17926a79 | 380 | |
248f219c | 381 | if (rx_pkt_len > 0) { |
84997905 DH |
382 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_full, seq, |
383 | rx_pkt_offset, rx_pkt_len, 0); | |
248f219c | 384 | ASSERTCMP(*_offset, ==, len); |
816c9fce | 385 | ret = 0; |
17926a79 DH |
386 | break; |
387 | } | |
388 | ||
248f219c DH |
389 | /* The whole packet has been transferred. */ |
390 | last = sp->hdr.flags & RXRPC_LAST_PACKET; | |
372ee163 | 391 | if (!(flags & MSG_PEEK)) |
248f219c DH |
392 | rxrpc_rotate_rx_window(call); |
393 | rx_pkt_offset = 0; | |
394 | rx_pkt_len = 0; | |
17926a79 | 395 | |
816c9fce DH |
396 | if (last) { |
397 | ASSERTCMP(seq, ==, READ_ONCE(call->rx_top)); | |
248f219c | 398 | ret = 1; |
816c9fce DH |
399 | goto out; |
400 | } | |
d7e15835 DH |
401 | |
402 | seq++; | |
248f219c | 403 | } |
816c9fce | 404 | |
248f219c DH |
405 | out: |
406 | if (!(flags & MSG_PEEK)) { | |
407 | call->rx_pkt_offset = rx_pkt_offset; | |
408 | call->rx_pkt_len = rx_pkt_len; | |
409 | } | |
816c9fce | 410 | done: |
84997905 DH |
411 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_data_return, seq, |
412 | rx_pkt_offset, rx_pkt_len, ret); | |
248f219c DH |
413 | return ret; |
414 | } | |
17926a79 | 415 | |
248f219c DH |
416 | /* |
417 | * Receive a message from an RxRPC socket | |
418 | * - we need to be careful about two or more threads calling recvmsg | |
419 | * simultaneously | |
420 | */ | |
421 | int rxrpc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, | |
422 | int flags) | |
423 | { | |
424 | struct rxrpc_call *call; | |
425 | struct rxrpc_sock *rx = rxrpc_sk(sock->sk); | |
426 | struct list_head *l; | |
427 | size_t copied = 0; | |
428 | long timeo; | |
429 | int ret; | |
430 | ||
431 | DEFINE_WAIT(wait); | |
432 | ||
84997905 | 433 | trace_rxrpc_recvmsg(NULL, rxrpc_recvmsg_enter, 0, 0, 0, 0); |
248f219c DH |
434 | |
435 | if (flags & (MSG_OOB | MSG_TRUNC)) | |
436 | return -EOPNOTSUPP; | |
437 | ||
438 | timeo = sock_rcvtimeo(&rx->sk, flags & MSG_DONTWAIT); | |
439 | ||
440 | try_again: | |
441 | lock_sock(&rx->sk); | |
442 | ||
443 | /* Return immediately if a client socket has no outstanding calls */ | |
444 | if (RB_EMPTY_ROOT(&rx->calls) && | |
445 | list_empty(&rx->recvmsg_q) && | |
446 | rx->sk.sk_state != RXRPC_SERVER_LISTENING) { | |
447 | release_sock(&rx->sk); | |
448 | return -ENODATA; | |
17926a79 DH |
449 | } |
450 | ||
248f219c DH |
451 | if (list_empty(&rx->recvmsg_q)) { |
452 | ret = -EWOULDBLOCK; | |
84997905 DH |
453 | if (timeo == 0) { |
454 | call = NULL; | |
248f219c | 455 | goto error_no_call; |
84997905 | 456 | } |
248f219c DH |
457 | |
458 | release_sock(&rx->sk); | |
459 | ||
460 | /* Wait for something to happen */ | |
461 | prepare_to_wait_exclusive(sk_sleep(&rx->sk), &wait, | |
462 | TASK_INTERRUPTIBLE); | |
463 | ret = sock_error(&rx->sk); | |
464 | if (ret) | |
465 | goto wait_error; | |
466 | ||
467 | if (list_empty(&rx->recvmsg_q)) { | |
468 | if (signal_pending(current)) | |
469 | goto wait_interrupted; | |
84997905 DH |
470 | trace_rxrpc_recvmsg(NULL, rxrpc_recvmsg_wait, |
471 | 0, 0, 0, 0); | |
248f219c | 472 | timeo = schedule_timeout(timeo); |
17926a79 | 473 | } |
248f219c DH |
474 | finish_wait(sk_sleep(&rx->sk), &wait); |
475 | goto try_again; | |
17926a79 DH |
476 | } |
477 | ||
248f219c DH |
478 | /* Find the next call and dequeue it if we're not just peeking. If we |
479 | * do dequeue it, that comes with a ref that we will need to release. | |
480 | */ | |
481 | write_lock_bh(&rx->recvmsg_lock); | |
482 | l = rx->recvmsg_q.next; | |
483 | call = list_entry(l, struct rxrpc_call, recvmsg_link); | |
484 | if (!(flags & MSG_PEEK)) | |
485 | list_del_init(&call->recvmsg_link); | |
486 | else | |
487 | rxrpc_get_call(call, rxrpc_call_got); | |
488 | write_unlock_bh(&rx->recvmsg_lock); | |
17926a79 | 489 | |
84997905 | 490 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_dequeue, 0, 0, 0, 0); |
248f219c DH |
491 | |
492 | if (test_bit(RXRPC_CALL_RELEASED, &call->flags)) | |
17926a79 | 493 | BUG(); |
248f219c DH |
494 | |
495 | if (test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) { | |
496 | if (flags & MSG_CMSG_COMPAT) { | |
497 | unsigned int id32 = call->user_call_ID; | |
498 | ||
499 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID, | |
500 | sizeof(unsigned int), &id32); | |
501 | } else { | |
502 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID, | |
503 | sizeof(unsigned long), | |
504 | &call->user_call_ID); | |
f5c17aae | 505 | } |
248f219c DH |
506 | if (ret < 0) |
507 | goto error; | |
508 | } | |
509 | ||
510 | if (msg->msg_name) { | |
511 | size_t len = sizeof(call->conn->params.peer->srx); | |
512 | memcpy(msg->msg_name, &call->conn->params.peer->srx, len); | |
513 | msg->msg_namelen = len; | |
514 | } | |
515 | ||
516 | switch (call->state) { | |
517 | case RXRPC_CALL_SERVER_ACCEPTING: | |
518 | ret = rxrpc_recvmsg_new_call(rx, call, msg, flags); | |
17926a79 | 519 | break; |
248f219c DH |
520 | case RXRPC_CALL_CLIENT_RECV_REPLY: |
521 | case RXRPC_CALL_SERVER_RECV_REQUEST: | |
522 | case RXRPC_CALL_SERVER_ACK_REQUEST: | |
523 | ret = rxrpc_recvmsg_data(sock, call, msg, &msg->msg_iter, len, | |
524 | flags, &copied); | |
525 | if (ret == -EAGAIN) | |
526 | ret = 0; | |
33b603fd DH |
527 | |
528 | if (after(call->rx_top, call->rx_hard_ack) && | |
529 | call->rxtx_buffer[(call->rx_hard_ack + 1) & RXRPC_RXTX_BUFF_MASK]) | |
530 | rxrpc_notify_socket(call); | |
17926a79 DH |
531 | break; |
532 | default: | |
248f219c | 533 | ret = 0; |
17926a79 DH |
534 | break; |
535 | } | |
536 | ||
537 | if (ret < 0) | |
248f219c | 538 | goto error; |
17926a79 | 539 | |
248f219c DH |
540 | if (call->state == RXRPC_CALL_COMPLETE) { |
541 | ret = rxrpc_recvmsg_term(call, msg); | |
542 | if (ret < 0) | |
543 | goto error; | |
544 | if (!(flags & MSG_PEEK)) | |
545 | rxrpc_release_call(rx, call); | |
546 | msg->msg_flags |= MSG_EOR; | |
547 | ret = 1; | |
17926a79 DH |
548 | } |
549 | ||
248f219c DH |
550 | if (ret == 0) |
551 | msg->msg_flags |= MSG_MORE; | |
552 | else | |
553 | msg->msg_flags &= ~MSG_MORE; | |
554 | ret = copied; | |
17926a79 | 555 | |
248f219c | 556 | error: |
fff72429 | 557 | rxrpc_put_call(call, rxrpc_call_put); |
248f219c DH |
558 | error_no_call: |
559 | release_sock(&rx->sk); | |
84997905 | 560 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_return, 0, 0, 0, ret); |
17926a79 DH |
561 | return ret; |
562 | ||
17926a79 DH |
563 | wait_interrupted: |
564 | ret = sock_intr_errno(timeo); | |
565 | wait_error: | |
4a4771a5 | 566 | finish_wait(sk_sleep(&rx->sk), &wait); |
84997905 DH |
567 | call = NULL; |
568 | goto error_no_call; | |
d001648e | 569 | } |
651350d1 DH |
570 | |
571 | /** | |
d001648e DH |
572 | * rxrpc_kernel_recv_data - Allow a kernel service to receive data/info |
573 | * @sock: The socket that the call exists on | |
574 | * @call: The call to send data through | |
575 | * @buf: The buffer to receive into | |
576 | * @size: The size of the buffer, including data already read | |
577 | * @_offset: The running offset into the buffer. | |
578 | * @want_more: True if more data is expected to be read | |
579 | * @_abort: Where the abort code is stored if -ECONNABORTED is returned | |
580 | * | |
581 | * Allow a kernel service to receive data and pick up information about the | |
582 | * state of a call. Returns 0 if got what was asked for and there's more | |
583 | * available, 1 if we got what was asked for and we're at the end of the data | |
584 | * and -EAGAIN if we need more data. | |
585 | * | |
586 | * Note that we may return -EAGAIN to drain empty packets at the end of the | |
587 | * data, even if we've already copied over the requested data. | |
651350d1 | 588 | * |
d001648e DH |
589 | * This function adds the amount it transfers to *_offset, so this should be |
590 | * precleared as appropriate. Note that the amount remaining in the buffer is | |
591 | * taken to be size - *_offset. | |
592 | * | |
593 | * *_abort should also be initialised to 0. | |
651350d1 | 594 | */ |
d001648e DH |
595 | int rxrpc_kernel_recv_data(struct socket *sock, struct rxrpc_call *call, |
596 | void *buf, size_t size, size_t *_offset, | |
597 | bool want_more, u32 *_abort) | |
651350d1 | 598 | { |
d001648e DH |
599 | struct iov_iter iter; |
600 | struct kvec iov; | |
601 | int ret; | |
651350d1 | 602 | |
248f219c DH |
603 | _enter("{%d,%s},%zu/%zu,%d", |
604 | call->debug_id, rxrpc_call_states[call->state], | |
605 | *_offset, size, want_more); | |
d001648e DH |
606 | |
607 | ASSERTCMP(*_offset, <=, size); | |
608 | ASSERTCMP(call->state, !=, RXRPC_CALL_SERVER_ACCEPTING); | |
651350d1 | 609 | |
d001648e DH |
610 | iov.iov_base = buf + *_offset; |
611 | iov.iov_len = size - *_offset; | |
612 | iov_iter_kvec(&iter, ITER_KVEC | READ, &iov, 1, size - *_offset); | |
613 | ||
614 | lock_sock(sock->sk); | |
615 | ||
616 | switch (call->state) { | |
617 | case RXRPC_CALL_CLIENT_RECV_REPLY: | |
618 | case RXRPC_CALL_SERVER_RECV_REQUEST: | |
619 | case RXRPC_CALL_SERVER_ACK_REQUEST: | |
248f219c DH |
620 | ret = rxrpc_recvmsg_data(sock, call, NULL, &iter, size, 0, |
621 | _offset); | |
d001648e DH |
622 | if (ret < 0) |
623 | goto out; | |
624 | ||
625 | /* We can only reach here with a partially full buffer if we | |
626 | * have reached the end of the data. We must otherwise have a | |
627 | * full buffer or have been given -EAGAIN. | |
628 | */ | |
629 | if (ret == 1) { | |
630 | if (*_offset < size) | |
631 | goto short_data; | |
632 | if (!want_more) | |
633 | goto read_phase_complete; | |
634 | ret = 0; | |
635 | goto out; | |
636 | } | |
637 | ||
638 | if (!want_more) | |
639 | goto excess_data; | |
640 | goto out; | |
641 | ||
642 | case RXRPC_CALL_COMPLETE: | |
643 | goto call_complete; | |
644 | ||
645 | default: | |
d001648e DH |
646 | ret = -EINPROGRESS; |
647 | goto out; | |
648 | } | |
649 | ||
650 | read_phase_complete: | |
651 | ret = 1; | |
652 | out: | |
653 | release_sock(sock->sk); | |
654 | _leave(" = %d [%zu,%d]", ret, *_offset, *_abort); | |
655 | return ret; | |
656 | ||
657 | short_data: | |
658 | ret = -EBADMSG; | |
659 | goto out; | |
660 | excess_data: | |
661 | ret = -EMSGSIZE; | |
662 | goto out; | |
663 | call_complete: | |
664 | *_abort = call->abort_code; | |
cf69207a | 665 | ret = -call->error; |
d001648e DH |
666 | if (call->completion == RXRPC_CALL_SUCCEEDED) { |
667 | ret = 1; | |
668 | if (size > 0) | |
669 | ret = -ECONNRESET; | |
670 | } | |
671 | goto out; | |
672 | } | |
673 | EXPORT_SYMBOL(rxrpc_kernel_recv_data); |