Loading...
1/*
2 * An implementation of key value pair (KVP) functionality for Linux.
3 *
4 *
5 * Copyright (C) 2010, Novell, Inc.
6 * Author : K. Y. Srinivasan <ksrinivasan@novell.com>
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 as published
10 * by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
15 * NON INFRINGEMENT. See the GNU General Public License for more
16 * details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21 *
22 */
23#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
24
25#include <linux/net.h>
26#include <linux/nls.h>
27#include <linux/connector.h>
28#include <linux/workqueue.h>
29#include <linux/hyperv.h>
30#include <asm/hyperv-tlfs.h>
31
32#include "hyperv_vmbus.h"
33#include "hv_utils_transport.h"
34
35/*
36 * Pre win8 version numbers used in ws2008 and ws 2008 r2 (win7)
37 */
38#define WS2008_SRV_MAJOR 1
39#define WS2008_SRV_MINOR 0
40#define WS2008_SRV_VERSION (WS2008_SRV_MAJOR << 16 | WS2008_SRV_MINOR)
41
42#define WIN7_SRV_MAJOR 3
43#define WIN7_SRV_MINOR 0
44#define WIN7_SRV_VERSION (WIN7_SRV_MAJOR << 16 | WIN7_SRV_MINOR)
45
46#define WIN8_SRV_MAJOR 4
47#define WIN8_SRV_MINOR 0
48#define WIN8_SRV_VERSION (WIN8_SRV_MAJOR << 16 | WIN8_SRV_MINOR)
49
50#define KVP_VER_COUNT 3
51static const int kvp_versions[] = {
52 WIN8_SRV_VERSION,
53 WIN7_SRV_VERSION,
54 WS2008_SRV_VERSION
55};
56
57#define FW_VER_COUNT 2
58static const int fw_versions[] = {
59 UTIL_FW_VERSION,
60 UTIL_WS2K8_FW_VERSION
61};
62
63/*
64 * Global state maintained for transaction that is being processed. For a class
65 * of integration services, including the "KVP service", the specified protocol
66 * is a "request/response" protocol which means that there can only be single
67 * outstanding transaction from the host at any given point in time. We use
68 * this to simplify memory management in this driver - we cache and process
69 * only one message at a time.
70 *
71 * While the request/response protocol is guaranteed by the host, we further
72 * ensure this by serializing packet processing in this driver - we do not
73 * read additional packets from the VMBUS until the current packet is fully
74 * handled.
75 */
76
77static struct {
78 int state; /* hvutil_device_state */
79 int recv_len; /* number of bytes received. */
80 struct hv_kvp_msg *kvp_msg; /* current message */
81 struct vmbus_channel *recv_channel; /* chn we got the request */
82 u64 recv_req_id; /* request ID. */
83} kvp_transaction;
84
85/*
86 * This state maintains the version number registered by the daemon.
87 */
88static int dm_reg_value;
89
90static void kvp_send_key(struct work_struct *dummy);
91
92
93static void kvp_respond_to_host(struct hv_kvp_msg *msg, int error);
94static void kvp_timeout_func(struct work_struct *dummy);
95static void kvp_host_handshake_func(struct work_struct *dummy);
96static void kvp_register(int);
97
98static DECLARE_DELAYED_WORK(kvp_timeout_work, kvp_timeout_func);
99static DECLARE_DELAYED_WORK(kvp_host_handshake_work, kvp_host_handshake_func);
100static DECLARE_WORK(kvp_sendkey_work, kvp_send_key);
101
102static const char kvp_devname[] = "vmbus/hv_kvp";
103static u8 *recv_buffer;
104static struct hvutil_transport *hvt;
105/*
106 * Register the kernel component with the user-level daemon.
107 * As part of this registration, pass the LIC version number.
108 * This number has no meaning, it satisfies the registration protocol.
109 */
110#define HV_DRV_VERSION "3.1"
111
112static void kvp_poll_wrapper(void *channel)
113{
114 /* Transaction is finished, reset the state here to avoid races. */
115 kvp_transaction.state = HVUTIL_READY;
116 tasklet_schedule(&((struct vmbus_channel *)channel)->callback_event);
117}
118
119static void kvp_register_done(void)
120{
121 /*
122 * If we're still negotiating with the host cancel the timeout
123 * work to not poll the channel twice.
124 */
125 pr_debug("KVP: userspace daemon registered\n");
126 cancel_delayed_work_sync(&kvp_host_handshake_work);
127 hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper);
128}
129
130static void
131kvp_register(int reg_value)
132{
133
134 struct hv_kvp_msg *kvp_msg;
135 char *version;
136
137 kvp_msg = kzalloc(sizeof(*kvp_msg), GFP_KERNEL);
138
139 if (kvp_msg) {
140 version = kvp_msg->body.kvp_register.version;
141 kvp_msg->kvp_hdr.operation = reg_value;
142 strcpy(version, HV_DRV_VERSION);
143
144 hvutil_transport_send(hvt, kvp_msg, sizeof(*kvp_msg),
145 kvp_register_done);
146 kfree(kvp_msg);
147 }
148}
149
150static void kvp_timeout_func(struct work_struct *dummy)
151{
152 /*
153 * If the timer fires, the user-mode component has not responded;
154 * process the pending transaction.
155 */
156 kvp_respond_to_host(NULL, HV_E_FAIL);
157
158 hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper);
159}
160
161static void kvp_host_handshake_func(struct work_struct *dummy)
162{
163 tasklet_schedule(&kvp_transaction.recv_channel->callback_event);
164}
165
166static int kvp_handle_handshake(struct hv_kvp_msg *msg)
167{
168 switch (msg->kvp_hdr.operation) {
169 case KVP_OP_REGISTER:
170 dm_reg_value = KVP_OP_REGISTER;
171 pr_info("KVP: IP injection functionality not available\n");
172 pr_info("KVP: Upgrade the KVP daemon\n");
173 break;
174 case KVP_OP_REGISTER1:
175 dm_reg_value = KVP_OP_REGISTER1;
176 break;
177 default:
178 pr_info("KVP: incompatible daemon\n");
179 pr_info("KVP: KVP version: %d, Daemon version: %d\n",
180 KVP_OP_REGISTER1, msg->kvp_hdr.operation);
181 return -EINVAL;
182 }
183
184 /*
185 * We have a compatible daemon; complete the handshake.
186 */
187 pr_debug("KVP: userspace daemon ver. %d connected\n",
188 msg->kvp_hdr.operation);
189 kvp_register(dm_reg_value);
190
191 return 0;
192}
193
194
195/*
196 * Callback when data is received from user mode.
197 */
198
199static int kvp_on_msg(void *msg, int len)
200{
201 struct hv_kvp_msg *message = (struct hv_kvp_msg *)msg;
202 struct hv_kvp_msg_enumerate *data;
203 int error = 0;
204
205 if (len < sizeof(*message))
206 return -EINVAL;
207
208 /*
209 * If we are negotiating the version information
210 * with the daemon; handle that first.
211 */
212
213 if (kvp_transaction.state < HVUTIL_READY) {
214 return kvp_handle_handshake(message);
215 }
216
217 /* We didn't send anything to userspace so the reply is spurious */
218 if (kvp_transaction.state < HVUTIL_USERSPACE_REQ)
219 return -EINVAL;
220
221 kvp_transaction.state = HVUTIL_USERSPACE_RECV;
222
223 /*
224 * Based on the version of the daemon, we propagate errors from the
225 * daemon differently.
226 */
227
228 data = &message->body.kvp_enum_data;
229
230 switch (dm_reg_value) {
231 case KVP_OP_REGISTER:
232 /*
233 * Null string is used to pass back error condition.
234 */
235 if (data->data.key[0] == 0)
236 error = HV_S_CONT;
237 break;
238
239 case KVP_OP_REGISTER1:
240 /*
241 * We use the message header information from
242 * the user level daemon to transmit errors.
243 */
244 error = message->error;
245 break;
246 }
247
248 /*
249 * Complete the transaction by forwarding the key value
250 * to the host. But first, cancel the timeout.
251 */
252 if (cancel_delayed_work_sync(&kvp_timeout_work)) {
253 kvp_respond_to_host(message, error);
254 hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper);
255 }
256
257 return 0;
258}
259
260
261static int process_ob_ipinfo(void *in_msg, void *out_msg, int op)
262{
263 struct hv_kvp_msg *in = in_msg;
264 struct hv_kvp_ip_msg *out = out_msg;
265 int len;
266
267 switch (op) {
268 case KVP_OP_GET_IP_INFO:
269 /*
270 * Transform all parameters into utf16 encoding.
271 */
272 len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.ip_addr,
273 strlen((char *)in->body.kvp_ip_val.ip_addr),
274 UTF16_HOST_ENDIAN,
275 (wchar_t *)out->kvp_ip_val.ip_addr,
276 MAX_IP_ADDR_SIZE);
277 if (len < 0)
278 return len;
279
280 len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.sub_net,
281 strlen((char *)in->body.kvp_ip_val.sub_net),
282 UTF16_HOST_ENDIAN,
283 (wchar_t *)out->kvp_ip_val.sub_net,
284 MAX_IP_ADDR_SIZE);
285 if (len < 0)
286 return len;
287
288 len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.gate_way,
289 strlen((char *)in->body.kvp_ip_val.gate_way),
290 UTF16_HOST_ENDIAN,
291 (wchar_t *)out->kvp_ip_val.gate_way,
292 MAX_GATEWAY_SIZE);
293 if (len < 0)
294 return len;
295
296 len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.dns_addr,
297 strlen((char *)in->body.kvp_ip_val.dns_addr),
298 UTF16_HOST_ENDIAN,
299 (wchar_t *)out->kvp_ip_val.dns_addr,
300 MAX_IP_ADDR_SIZE);
301 if (len < 0)
302 return len;
303
304 len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.adapter_id,
305 strlen((char *)in->body.kvp_ip_val.adapter_id),
306 UTF16_HOST_ENDIAN,
307 (wchar_t *)out->kvp_ip_val.adapter_id,
308 MAX_ADAPTER_ID_SIZE);
309 if (len < 0)
310 return len;
311
312 out->kvp_ip_val.dhcp_enabled =
313 in->body.kvp_ip_val.dhcp_enabled;
314 out->kvp_ip_val.addr_family =
315 in->body.kvp_ip_val.addr_family;
316 }
317
318 return 0;
319}
320
321static void process_ib_ipinfo(void *in_msg, void *out_msg, int op)
322{
323 struct hv_kvp_ip_msg *in = in_msg;
324 struct hv_kvp_msg *out = out_msg;
325
326 switch (op) {
327 case KVP_OP_SET_IP_INFO:
328 /*
329 * Transform all parameters into utf8 encoding.
330 */
331 utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.ip_addr,
332 MAX_IP_ADDR_SIZE,
333 UTF16_LITTLE_ENDIAN,
334 (__u8 *)out->body.kvp_ip_val.ip_addr,
335 MAX_IP_ADDR_SIZE);
336
337 utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.sub_net,
338 MAX_IP_ADDR_SIZE,
339 UTF16_LITTLE_ENDIAN,
340 (__u8 *)out->body.kvp_ip_val.sub_net,
341 MAX_IP_ADDR_SIZE);
342
343 utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.gate_way,
344 MAX_GATEWAY_SIZE,
345 UTF16_LITTLE_ENDIAN,
346 (__u8 *)out->body.kvp_ip_val.gate_way,
347 MAX_GATEWAY_SIZE);
348
349 utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.dns_addr,
350 MAX_IP_ADDR_SIZE,
351 UTF16_LITTLE_ENDIAN,
352 (__u8 *)out->body.kvp_ip_val.dns_addr,
353 MAX_IP_ADDR_SIZE);
354
355 out->body.kvp_ip_val.dhcp_enabled = in->kvp_ip_val.dhcp_enabled;
356
357 fallthrough;
358
359 case KVP_OP_GET_IP_INFO:
360 utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.adapter_id,
361 MAX_ADAPTER_ID_SIZE,
362 UTF16_LITTLE_ENDIAN,
363 (__u8 *)out->body.kvp_ip_val.adapter_id,
364 MAX_ADAPTER_ID_SIZE);
365
366 out->body.kvp_ip_val.addr_family = in->kvp_ip_val.addr_family;
367 }
368}
369
370
371
372
373static void
374kvp_send_key(struct work_struct *dummy)
375{
376 struct hv_kvp_msg *message;
377 struct hv_kvp_msg *in_msg;
378 __u8 operation = kvp_transaction.kvp_msg->kvp_hdr.operation;
379 __u8 pool = kvp_transaction.kvp_msg->kvp_hdr.pool;
380 __u32 val32;
381 __u64 val64;
382 int rc;
383
384 /* The transaction state is wrong. */
385 if (kvp_transaction.state != HVUTIL_HOSTMSG_RECEIVED)
386 return;
387
388 message = kzalloc(sizeof(*message), GFP_KERNEL);
389 if (!message)
390 return;
391
392 message->kvp_hdr.operation = operation;
393 message->kvp_hdr.pool = pool;
394 in_msg = kvp_transaction.kvp_msg;
395
396 /*
397 * The key/value strings sent from the host are encoded
398 * in utf16; convert it to utf8 strings.
399 * The host assures us that the utf16 strings will not exceed
400 * the max lengths specified. We will however, reserve room
401 * for the string terminating character - in the utf16s_utf8s()
402 * function we limit the size of the buffer where the converted
403 * string is placed to HV_KVP_EXCHANGE_MAX_*_SIZE -1 to guarantee
404 * that the strings can be properly terminated!
405 */
406
407 switch (message->kvp_hdr.operation) {
408 case KVP_OP_SET_IP_INFO:
409 process_ib_ipinfo(in_msg, message, KVP_OP_SET_IP_INFO);
410 break;
411 case KVP_OP_GET_IP_INFO:
412 /*
413 * We only need to pass on the info of operation, adapter_id
414 * and addr_family to the userland kvp daemon.
415 */
416 process_ib_ipinfo(in_msg, message, KVP_OP_GET_IP_INFO);
417 break;
418 case KVP_OP_SET:
419 switch (in_msg->body.kvp_set.data.value_type) {
420 case REG_SZ:
421 /*
422 * The value is a string - utf16 encoding.
423 */
424 message->body.kvp_set.data.value_size =
425 utf16s_to_utf8s(
426 (wchar_t *)in_msg->body.kvp_set.data.value,
427 in_msg->body.kvp_set.data.value_size,
428 UTF16_LITTLE_ENDIAN,
429 message->body.kvp_set.data.value,
430 HV_KVP_EXCHANGE_MAX_VALUE_SIZE - 1) + 1;
431 break;
432
433 case REG_U32:
434 /*
435 * The value is a 32 bit scalar.
436 * We save this as a utf8 string.
437 */
438 val32 = in_msg->body.kvp_set.data.value_u32;
439 message->body.kvp_set.data.value_size =
440 sprintf(message->body.kvp_set.data.value,
441 "%u", val32) + 1;
442 break;
443
444 case REG_U64:
445 /*
446 * The value is a 64 bit scalar.
447 * We save this as a utf8 string.
448 */
449 val64 = in_msg->body.kvp_set.data.value_u64;
450 message->body.kvp_set.data.value_size =
451 sprintf(message->body.kvp_set.data.value,
452 "%llu", val64) + 1;
453 break;
454
455 }
456
457 /*
458 * The key is always a string - utf16 encoding.
459 */
460 message->body.kvp_set.data.key_size =
461 utf16s_to_utf8s(
462 (wchar_t *)in_msg->body.kvp_set.data.key,
463 in_msg->body.kvp_set.data.key_size,
464 UTF16_LITTLE_ENDIAN,
465 message->body.kvp_set.data.key,
466 HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1) + 1;
467
468 break;
469
470 case KVP_OP_GET:
471 message->body.kvp_get.data.key_size =
472 utf16s_to_utf8s(
473 (wchar_t *)in_msg->body.kvp_get.data.key,
474 in_msg->body.kvp_get.data.key_size,
475 UTF16_LITTLE_ENDIAN,
476 message->body.kvp_get.data.key,
477 HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1) + 1;
478 break;
479
480 case KVP_OP_DELETE:
481 message->body.kvp_delete.key_size =
482 utf16s_to_utf8s(
483 (wchar_t *)in_msg->body.kvp_delete.key,
484 in_msg->body.kvp_delete.key_size,
485 UTF16_LITTLE_ENDIAN,
486 message->body.kvp_delete.key,
487 HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1) + 1;
488 break;
489
490 case KVP_OP_ENUMERATE:
491 message->body.kvp_enum_data.index =
492 in_msg->body.kvp_enum_data.index;
493 break;
494 }
495
496 kvp_transaction.state = HVUTIL_USERSPACE_REQ;
497 rc = hvutil_transport_send(hvt, message, sizeof(*message), NULL);
498 if (rc) {
499 pr_debug("KVP: failed to communicate to the daemon: %d\n", rc);
500 if (cancel_delayed_work_sync(&kvp_timeout_work)) {
501 kvp_respond_to_host(message, HV_E_FAIL);
502 kvp_transaction.state = HVUTIL_READY;
503 }
504 }
505
506 kfree(message);
507}
508
509/*
510 * Send a response back to the host.
511 */
512
513static void
514kvp_respond_to_host(struct hv_kvp_msg *msg_to_host, int error)
515{
516 struct hv_kvp_msg *kvp_msg;
517 struct hv_kvp_exchg_msg_value *kvp_data;
518 char *key_name;
519 char *value;
520 struct icmsg_hdr *icmsghdrp;
521 int keylen = 0;
522 int valuelen = 0;
523 u32 buf_len;
524 struct vmbus_channel *channel;
525 u64 req_id;
526 int ret;
527
528 /*
529 * Copy the global state for completing the transaction. Note that
530 * only one transaction can be active at a time.
531 */
532
533 buf_len = kvp_transaction.recv_len;
534 channel = kvp_transaction.recv_channel;
535 req_id = kvp_transaction.recv_req_id;
536
537 icmsghdrp = (struct icmsg_hdr *)
538 &recv_buffer[sizeof(struct vmbuspipe_hdr)];
539
540 if (channel->onchannel_callback == NULL)
541 /*
542 * We have raced with util driver being unloaded;
543 * silently return.
544 */
545 return;
546
547 icmsghdrp->status = error;
548
549 /*
550 * If the error parameter is set, terminate the host's enumeration
551 * on this pool.
552 */
553 if (error) {
554 /*
555 * Something failed or we have timed out;
556 * terminate the current host-side iteration.
557 */
558 goto response_done;
559 }
560
561 kvp_msg = (struct hv_kvp_msg *)
562 &recv_buffer[sizeof(struct vmbuspipe_hdr) +
563 sizeof(struct icmsg_hdr)];
564
565 switch (kvp_transaction.kvp_msg->kvp_hdr.operation) {
566 case KVP_OP_GET_IP_INFO:
567 ret = process_ob_ipinfo(msg_to_host,
568 (struct hv_kvp_ip_msg *)kvp_msg,
569 KVP_OP_GET_IP_INFO);
570 if (ret < 0)
571 icmsghdrp->status = HV_E_FAIL;
572
573 goto response_done;
574 case KVP_OP_SET_IP_INFO:
575 goto response_done;
576 case KVP_OP_GET:
577 kvp_data = &kvp_msg->body.kvp_get.data;
578 goto copy_value;
579
580 case KVP_OP_SET:
581 case KVP_OP_DELETE:
582 goto response_done;
583
584 default:
585 break;
586 }
587
588 kvp_data = &kvp_msg->body.kvp_enum_data.data;
589 key_name = msg_to_host->body.kvp_enum_data.data.key;
590
591 /*
592 * The windows host expects the key/value pair to be encoded
593 * in utf16. Ensure that the key/value size reported to the host
594 * will be less than or equal to the MAX size (including the
595 * terminating character).
596 */
597 keylen = utf8s_to_utf16s(key_name, strlen(key_name), UTF16_HOST_ENDIAN,
598 (wchar_t *) kvp_data->key,
599 (HV_KVP_EXCHANGE_MAX_KEY_SIZE / 2) - 2);
600 kvp_data->key_size = 2*(keylen + 1); /* utf16 encoding */
601
602copy_value:
603 value = msg_to_host->body.kvp_enum_data.data.value;
604 valuelen = utf8s_to_utf16s(value, strlen(value), UTF16_HOST_ENDIAN,
605 (wchar_t *) kvp_data->value,
606 (HV_KVP_EXCHANGE_MAX_VALUE_SIZE / 2) - 2);
607 kvp_data->value_size = 2*(valuelen + 1); /* utf16 encoding */
608
609 /*
610 * If the utf8s to utf16s conversion failed; notify host
611 * of the error.
612 */
613 if ((keylen < 0) || (valuelen < 0))
614 icmsghdrp->status = HV_E_FAIL;
615
616 kvp_data->value_type = REG_SZ; /* all our values are strings */
617
618response_done:
619 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
620
621 vmbus_sendpacket(channel, recv_buffer, buf_len, req_id,
622 VM_PKT_DATA_INBAND, 0);
623}
624
625/*
626 * This callback is invoked when we get a KVP message from the host.
627 * The host ensures that only one KVP transaction can be active at a time.
628 * KVP implementation in Linux needs to forward the key to a user-mde
629 * component to retrieve the corresponding value. Consequently, we cannot
630 * respond to the host in the context of this callback. Since the host
631 * guarantees that at most only one transaction can be active at a time,
632 * we stash away the transaction state in a set of global variables.
633 */
634
635void hv_kvp_onchannelcallback(void *context)
636{
637 struct vmbus_channel *channel = context;
638 u32 recvlen;
639 u64 requestid;
640
641 struct hv_kvp_msg *kvp_msg;
642
643 struct icmsg_hdr *icmsghdrp;
644 int kvp_srv_version;
645 static enum {NEGO_NOT_STARTED,
646 NEGO_IN_PROGRESS,
647 NEGO_FINISHED} host_negotiatied = NEGO_NOT_STARTED;
648
649 if (kvp_transaction.state < HVUTIL_READY) {
650 /*
651 * If userspace daemon is not connected and host is asking
652 * us to negotiate we need to delay to not lose messages.
653 * This is important for Failover IP setting.
654 */
655 if (host_negotiatied == NEGO_NOT_STARTED) {
656 host_negotiatied = NEGO_IN_PROGRESS;
657 schedule_delayed_work(&kvp_host_handshake_work,
658 HV_UTIL_NEGO_TIMEOUT * HZ);
659 }
660 return;
661 }
662 if (kvp_transaction.state > HVUTIL_READY)
663 return;
664
665 if (vmbus_recvpacket(channel, recv_buffer, HV_HYP_PAGE_SIZE * 4, &recvlen, &requestid)) {
666 pr_err_ratelimited("KVP request received. Could not read into recv buf\n");
667 return;
668 }
669
670 if (!recvlen)
671 return;
672
673 /* Ensure recvlen is big enough to read header data */
674 if (recvlen < ICMSG_HDR) {
675 pr_err_ratelimited("KVP request received. Packet length too small: %d\n",
676 recvlen);
677 return;
678 }
679
680 icmsghdrp = (struct icmsg_hdr *)&recv_buffer[sizeof(struct vmbuspipe_hdr)];
681
682 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
683 if (vmbus_prep_negotiate_resp(icmsghdrp,
684 recv_buffer, recvlen,
685 fw_versions, FW_VER_COUNT,
686 kvp_versions, KVP_VER_COUNT,
687 NULL, &kvp_srv_version)) {
688 pr_info("KVP IC version %d.%d\n",
689 kvp_srv_version >> 16,
690 kvp_srv_version & 0xFFFF);
691 }
692 } else if (icmsghdrp->icmsgtype == ICMSGTYPE_KVPEXCHANGE) {
693 /*
694 * recvlen is not checked against sizeof(struct kvp_msg) because kvp_msg contains
695 * a union of structs and the msg type received is not known. Code using this
696 * struct should provide validation when accessing its fields.
697 */
698 kvp_msg = (struct hv_kvp_msg *)&recv_buffer[ICMSG_HDR];
699
700 /*
701 * Stash away this global state for completing the
702 * transaction; note transactions are serialized.
703 */
704
705 kvp_transaction.recv_len = recvlen;
706 kvp_transaction.recv_req_id = requestid;
707 kvp_transaction.kvp_msg = kvp_msg;
708
709 if (kvp_transaction.state < HVUTIL_READY) {
710 /* Userspace is not registered yet */
711 kvp_respond_to_host(NULL, HV_E_FAIL);
712 return;
713 }
714 kvp_transaction.state = HVUTIL_HOSTMSG_RECEIVED;
715
716 /*
717 * Get the information from the
718 * user-mode component.
719 * component. This transaction will be
720 * completed when we get the value from
721 * the user-mode component.
722 * Set a timeout to deal with
723 * user-mode not responding.
724 */
725 schedule_work(&kvp_sendkey_work);
726 schedule_delayed_work(&kvp_timeout_work,
727 HV_UTIL_TIMEOUT * HZ);
728
729 return;
730
731 } else {
732 pr_err_ratelimited("KVP request received. Invalid msg type: %d\n",
733 icmsghdrp->icmsgtype);
734 return;
735 }
736
737 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
738 | ICMSGHDRFLAG_RESPONSE;
739
740 vmbus_sendpacket(channel, recv_buffer,
741 recvlen, requestid,
742 VM_PKT_DATA_INBAND, 0);
743
744 host_negotiatied = NEGO_FINISHED;
745 hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper);
746}
747
748static void kvp_on_reset(void)
749{
750 if (cancel_delayed_work_sync(&kvp_timeout_work))
751 kvp_respond_to_host(NULL, HV_E_FAIL);
752 kvp_transaction.state = HVUTIL_DEVICE_INIT;
753}
754
755int
756hv_kvp_init(struct hv_util_service *srv)
757{
758 recv_buffer = srv->recv_buffer;
759 kvp_transaction.recv_channel = srv->channel;
760 kvp_transaction.recv_channel->max_pkt_size = HV_HYP_PAGE_SIZE * 4;
761
762 /*
763 * When this driver loads, the user level daemon that
764 * processes the host requests may not yet be running.
765 * Defer processing channel callbacks until the daemon
766 * has registered.
767 */
768 kvp_transaction.state = HVUTIL_DEVICE_INIT;
769
770 hvt = hvutil_transport_init(kvp_devname, CN_KVP_IDX, CN_KVP_VAL,
771 kvp_on_msg, kvp_on_reset);
772 if (!hvt)
773 return -EFAULT;
774
775 return 0;
776}
777
778static void hv_kvp_cancel_work(void)
779{
780 cancel_delayed_work_sync(&kvp_host_handshake_work);
781 cancel_delayed_work_sync(&kvp_timeout_work);
782 cancel_work_sync(&kvp_sendkey_work);
783}
784
785int hv_kvp_pre_suspend(void)
786{
787 struct vmbus_channel *channel = kvp_transaction.recv_channel;
788
789 tasklet_disable(&channel->callback_event);
790
791 /*
792 * If there is a pending transtion, it's unnecessary to tell the host
793 * that the transaction will fail, because that is implied when
794 * util_suspend() calls vmbus_close() later.
795 */
796 hv_kvp_cancel_work();
797
798 /*
799 * Forece the state to READY to handle the ICMSGTYPE_NEGOTIATE message
800 * later. The user space daemon may go out of order and its write()
801 * may fail with EINVAL: this doesn't matter since the daemon will
802 * reset the device by closing and re-opening it.
803 */
804 kvp_transaction.state = HVUTIL_READY;
805 return 0;
806}
807
808int hv_kvp_pre_resume(void)
809{
810 struct vmbus_channel *channel = kvp_transaction.recv_channel;
811
812 tasklet_enable(&channel->callback_event);
813
814 return 0;
815}
816
817void hv_kvp_deinit(void)
818{
819 kvp_transaction.state = HVUTIL_DEVICE_DYING;
820
821 hv_kvp_cancel_work();
822
823 hvutil_transport_destroy(hvt);
824}
1/*
2 * An implementation of key value pair (KVP) functionality for Linux.
3 *
4 *
5 * Copyright (C) 2010, Novell, Inc.
6 * Author : K. Y. Srinivasan <ksrinivasan@novell.com>
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 as published
10 * by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
15 * NON INFRINGEMENT. See the GNU General Public License for more
16 * details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21 *
22 */
23#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
24
25#include <linux/net.h>
26#include <linux/nls.h>
27#include <linux/connector.h>
28#include <linux/workqueue.h>
29#include <linux/hyperv.h>
30
31
32
33/*
34 * Global state maintained for transaction that is being processed.
35 * Note that only one transaction can be active at any point in time.
36 *
37 * This state is set when we receive a request from the host; we
38 * cleanup this state when the transaction is completed - when we respond
39 * to the host with the key value.
40 */
41
42static struct {
43 bool active; /* transaction status - active or not */
44 int recv_len; /* number of bytes received. */
45 struct hv_kvp_msg *kvp_msg; /* current message */
46 struct vmbus_channel *recv_channel; /* chn we got the request */
47 u64 recv_req_id; /* request ID. */
48 void *kvp_context; /* for the channel callback */
49} kvp_transaction;
50
51static void kvp_send_key(struct work_struct *dummy);
52
53#define TIMEOUT_FIRED 1
54
55static void kvp_respond_to_host(char *key, char *value, int error);
56static void kvp_work_func(struct work_struct *dummy);
57static void kvp_register(void);
58
59static DECLARE_DELAYED_WORK(kvp_work, kvp_work_func);
60static DECLARE_WORK(kvp_sendkey_work, kvp_send_key);
61
62static struct cb_id kvp_id = { CN_KVP_IDX, CN_KVP_VAL };
63static const char kvp_name[] = "kvp_kernel_module";
64static u8 *recv_buffer;
65/*
66 * Register the kernel component with the user-level daemon.
67 * As part of this registration, pass the LIC version number.
68 */
69
70static void
71kvp_register(void)
72{
73
74 struct cn_msg *msg;
75 struct hv_kvp_msg *kvp_msg;
76 char *version;
77
78 msg = kzalloc(sizeof(*msg) + sizeof(struct hv_kvp_msg), GFP_ATOMIC);
79
80 if (msg) {
81 kvp_msg = (struct hv_kvp_msg *)msg->data;
82 version = kvp_msg->body.kvp_register.version;
83 msg->id.idx = CN_KVP_IDX;
84 msg->id.val = CN_KVP_VAL;
85
86 kvp_msg->kvp_hdr.operation = KVP_OP_REGISTER;
87 strcpy(version, HV_DRV_VERSION);
88 msg->len = sizeof(struct hv_kvp_msg);
89 cn_netlink_send(msg, 0, GFP_ATOMIC);
90 kfree(msg);
91 }
92}
93static void
94kvp_work_func(struct work_struct *dummy)
95{
96 /*
97 * If the timer fires, the user-mode component has not responded;
98 * process the pending transaction.
99 */
100 kvp_respond_to_host("Unknown key", "Guest timed out", TIMEOUT_FIRED);
101}
102
103/*
104 * Callback when data is received from user mode.
105 */
106
107static void
108kvp_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
109{
110 struct hv_kvp_msg *message;
111 struct hv_kvp_msg_enumerate *data;
112
113 message = (struct hv_kvp_msg *)msg->data;
114 switch (message->kvp_hdr.operation) {
115 case KVP_OP_REGISTER:
116 pr_info("KVP: user-mode registering done.\n");
117 kvp_register();
118 kvp_transaction.active = false;
119 hv_kvp_onchannelcallback(kvp_transaction.kvp_context);
120 break;
121
122 default:
123 data = &message->body.kvp_enum_data;
124 /*
125 * Complete the transaction by forwarding the key value
126 * to the host. But first, cancel the timeout.
127 */
128 if (cancel_delayed_work_sync(&kvp_work))
129 kvp_respond_to_host(data->data.key,
130 data->data.value,
131 !strlen(data->data.key));
132 }
133}
134
135static void
136kvp_send_key(struct work_struct *dummy)
137{
138 struct cn_msg *msg;
139 struct hv_kvp_msg *message;
140 struct hv_kvp_msg *in_msg;
141 __u8 operation = kvp_transaction.kvp_msg->kvp_hdr.operation;
142 __u8 pool = kvp_transaction.kvp_msg->kvp_hdr.pool;
143 __u32 val32;
144 __u64 val64;
145
146 msg = kzalloc(sizeof(*msg) + sizeof(struct hv_kvp_msg) , GFP_ATOMIC);
147 if (!msg)
148 return;
149
150 msg->id.idx = CN_KVP_IDX;
151 msg->id.val = CN_KVP_VAL;
152
153 message = (struct hv_kvp_msg *)msg->data;
154 message->kvp_hdr.operation = operation;
155 message->kvp_hdr.pool = pool;
156 in_msg = kvp_transaction.kvp_msg;
157
158 /*
159 * The key/value strings sent from the host are encoded in
160 * in utf16; convert it to utf8 strings.
161 * The host assures us that the utf16 strings will not exceed
162 * the max lengths specified. We will however, reserve room
163 * for the string terminating character - in the utf16s_utf8s()
164 * function we limit the size of the buffer where the converted
165 * string is placed to HV_KVP_EXCHANGE_MAX_*_SIZE -1 to gaurantee
166 * that the strings can be properly terminated!
167 */
168
169 switch (message->kvp_hdr.operation) {
170 case KVP_OP_SET:
171 switch (in_msg->body.kvp_set.data.value_type) {
172 case REG_SZ:
173 /*
174 * The value is a string - utf16 encoding.
175 */
176 message->body.kvp_set.data.value_size =
177 utf16s_to_utf8s(
178 (wchar_t *)in_msg->body.kvp_set.data.value,
179 in_msg->body.kvp_set.data.value_size,
180 UTF16_LITTLE_ENDIAN,
181 message->body.kvp_set.data.value,
182 HV_KVP_EXCHANGE_MAX_VALUE_SIZE - 1) + 1;
183 break;
184
185 case REG_U32:
186 /*
187 * The value is a 32 bit scalar.
188 * We save this as a utf8 string.
189 */
190 val32 = in_msg->body.kvp_set.data.value_u32;
191 message->body.kvp_set.data.value_size =
192 sprintf(message->body.kvp_set.data.value,
193 "%d", val32) + 1;
194 break;
195
196 case REG_U64:
197 /*
198 * The value is a 64 bit scalar.
199 * We save this as a utf8 string.
200 */
201 val64 = in_msg->body.kvp_set.data.value_u64;
202 message->body.kvp_set.data.value_size =
203 sprintf(message->body.kvp_set.data.value,
204 "%llu", val64) + 1;
205 break;
206
207 }
208 case KVP_OP_GET:
209 message->body.kvp_set.data.key_size =
210 utf16s_to_utf8s(
211 (wchar_t *)in_msg->body.kvp_set.data.key,
212 in_msg->body.kvp_set.data.key_size,
213 UTF16_LITTLE_ENDIAN,
214 message->body.kvp_set.data.key,
215 HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1) + 1;
216 break;
217
218 case KVP_OP_DELETE:
219 message->body.kvp_delete.key_size =
220 utf16s_to_utf8s(
221 (wchar_t *)in_msg->body.kvp_delete.key,
222 in_msg->body.kvp_delete.key_size,
223 UTF16_LITTLE_ENDIAN,
224 message->body.kvp_delete.key,
225 HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1) + 1;
226 break;
227
228 case KVP_OP_ENUMERATE:
229 message->body.kvp_enum_data.index =
230 in_msg->body.kvp_enum_data.index;
231 break;
232 }
233
234 msg->len = sizeof(struct hv_kvp_msg);
235 cn_netlink_send(msg, 0, GFP_ATOMIC);
236 kfree(msg);
237
238 return;
239}
240
241/*
242 * Send a response back to the host.
243 */
244
245static void
246kvp_respond_to_host(char *key, char *value, int error)
247{
248 struct hv_kvp_msg *kvp_msg;
249 struct hv_kvp_exchg_msg_value *kvp_data;
250 char *key_name;
251 struct icmsg_hdr *icmsghdrp;
252 int keylen = 0;
253 int valuelen = 0;
254 u32 buf_len;
255 struct vmbus_channel *channel;
256 u64 req_id;
257
258 /*
259 * If a transaction is not active; log and return.
260 */
261
262 if (!kvp_transaction.active) {
263 /*
264 * This is a spurious call!
265 */
266 pr_warn("KVP: Transaction not active\n");
267 return;
268 }
269 /*
270 * Copy the global state for completing the transaction. Note that
271 * only one transaction can be active at a time.
272 */
273
274 buf_len = kvp_transaction.recv_len;
275 channel = kvp_transaction.recv_channel;
276 req_id = kvp_transaction.recv_req_id;
277
278 kvp_transaction.active = false;
279
280 icmsghdrp = (struct icmsg_hdr *)
281 &recv_buffer[sizeof(struct vmbuspipe_hdr)];
282
283 if (channel->onchannel_callback == NULL)
284 /*
285 * We have raced with util driver being unloaded;
286 * silently return.
287 */
288 return;
289
290
291 /*
292 * If the error parameter is set, terminate the host's enumeration
293 * on this pool.
294 */
295 if (error) {
296 /*
297 * Something failed or the we have timedout;
298 * terminate the current host-side iteration.
299 */
300 icmsghdrp->status = HV_S_CONT;
301 goto response_done;
302 }
303
304 icmsghdrp->status = HV_S_OK;
305
306 kvp_msg = (struct hv_kvp_msg *)
307 &recv_buffer[sizeof(struct vmbuspipe_hdr) +
308 sizeof(struct icmsg_hdr)];
309
310 switch (kvp_transaction.kvp_msg->kvp_hdr.operation) {
311 case KVP_OP_GET:
312 kvp_data = &kvp_msg->body.kvp_get.data;
313 goto copy_value;
314
315 case KVP_OP_SET:
316 case KVP_OP_DELETE:
317 goto response_done;
318
319 default:
320 break;
321 }
322
323 kvp_data = &kvp_msg->body.kvp_enum_data.data;
324 key_name = key;
325
326 /*
327 * The windows host expects the key/value pair to be encoded
328 * in utf16. Ensure that the key/value size reported to the host
329 * will be less than or equal to the MAX size (including the
330 * terminating character).
331 */
332 keylen = utf8s_to_utf16s(key_name, strlen(key_name), UTF16_HOST_ENDIAN,
333 (wchar_t *) kvp_data->key,
334 (HV_KVP_EXCHANGE_MAX_KEY_SIZE / 2) - 2);
335 kvp_data->key_size = 2*(keylen + 1); /* utf16 encoding */
336
337copy_value:
338 valuelen = utf8s_to_utf16s(value, strlen(value), UTF16_HOST_ENDIAN,
339 (wchar_t *) kvp_data->value,
340 (HV_KVP_EXCHANGE_MAX_VALUE_SIZE / 2) - 2);
341 kvp_data->value_size = 2*(valuelen + 1); /* utf16 encoding */
342
343 /*
344 * If the utf8s to utf16s conversion failed; notify host
345 * of the error.
346 */
347 if ((keylen < 0) || (valuelen < 0))
348 icmsghdrp->status = HV_E_FAIL;
349
350 kvp_data->value_type = REG_SZ; /* all our values are strings */
351
352response_done:
353 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
354
355 vmbus_sendpacket(channel, recv_buffer, buf_len, req_id,
356 VM_PKT_DATA_INBAND, 0);
357
358}
359
360/*
361 * This callback is invoked when we get a KVP message from the host.
362 * The host ensures that only one KVP transaction can be active at a time.
363 * KVP implementation in Linux needs to forward the key to a user-mde
364 * component to retrive the corresponding value. Consequently, we cannot
365 * respond to the host in the conext of this callback. Since the host
366 * guarantees that at most only one transaction can be active at a time,
367 * we stash away the transaction state in a set of global variables.
368 */
369
370void hv_kvp_onchannelcallback(void *context)
371{
372 struct vmbus_channel *channel = context;
373 u32 recvlen;
374 u64 requestid;
375
376 struct hv_kvp_msg *kvp_msg;
377
378 struct icmsg_hdr *icmsghdrp;
379 struct icmsg_negotiate *negop = NULL;
380
381 if (kvp_transaction.active) {
382 /*
383 * We will defer processing this callback once
384 * the current transaction is complete.
385 */
386 kvp_transaction.kvp_context = context;
387 return;
388 }
389
390 vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE, &recvlen, &requestid);
391
392 if (recvlen > 0) {
393 icmsghdrp = (struct icmsg_hdr *)&recv_buffer[
394 sizeof(struct vmbuspipe_hdr)];
395
396 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
397 vmbus_prep_negotiate_resp(icmsghdrp, negop,
398 recv_buffer, MAX_SRV_VER, MAX_SRV_VER);
399 } else {
400 kvp_msg = (struct hv_kvp_msg *)&recv_buffer[
401 sizeof(struct vmbuspipe_hdr) +
402 sizeof(struct icmsg_hdr)];
403
404 /*
405 * Stash away this global state for completing the
406 * transaction; note transactions are serialized.
407 */
408
409 kvp_transaction.recv_len = recvlen;
410 kvp_transaction.recv_channel = channel;
411 kvp_transaction.recv_req_id = requestid;
412 kvp_transaction.active = true;
413 kvp_transaction.kvp_msg = kvp_msg;
414
415 /*
416 * Get the information from the
417 * user-mode component.
418 * component. This transaction will be
419 * completed when we get the value from
420 * the user-mode component.
421 * Set a timeout to deal with
422 * user-mode not responding.
423 */
424 schedule_work(&kvp_sendkey_work);
425 schedule_delayed_work(&kvp_work, 5*HZ);
426
427 return;
428
429 }
430
431 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
432 | ICMSGHDRFLAG_RESPONSE;
433
434 vmbus_sendpacket(channel, recv_buffer,
435 recvlen, requestid,
436 VM_PKT_DATA_INBAND, 0);
437 }
438
439}
440
441int
442hv_kvp_init(struct hv_util_service *srv)
443{
444 int err;
445
446 err = cn_add_callback(&kvp_id, kvp_name, kvp_cn_callback);
447 if (err)
448 return err;
449 recv_buffer = srv->recv_buffer;
450
451 /*
452 * When this driver loads, the user level daemon that
453 * processes the host requests may not yet be running.
454 * Defer processing channel callbacks until the daemon
455 * has registered.
456 */
457 kvp_transaction.active = true;
458
459 return 0;
460}
461
462void hv_kvp_deinit(void)
463{
464 cn_del_callback(&kvp_id);
465 cancel_delayed_work_sync(&kvp_work);
466 cancel_work_sync(&kvp_sendkey_work);
467}