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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#include "hyperv_vmbus.h"
32#include "hv_utils_transport.h"
33
34/*
35 * Pre win8 version numbers used in ws2008 and ws 2008 r2 (win7)
36 */
37#define WS2008_SRV_MAJOR 1
38#define WS2008_SRV_MINOR 0
39#define WS2008_SRV_VERSION (WS2008_SRV_MAJOR << 16 | WS2008_SRV_MINOR)
40
41#define WIN7_SRV_MAJOR 3
42#define WIN7_SRV_MINOR 0
43#define WIN7_SRV_VERSION (WIN7_SRV_MAJOR << 16 | WIN7_SRV_MINOR)
44
45#define WIN8_SRV_MAJOR 4
46#define WIN8_SRV_MINOR 0
47#define WIN8_SRV_VERSION (WIN8_SRV_MAJOR << 16 | WIN8_SRV_MINOR)
48
49/*
50 * Global state maintained for transaction that is being processed. For a class
51 * of integration services, including the "KVP service", the specified protocol
52 * is a "request/response" protocol which means that there can only be single
53 * outstanding transaction from the host at any given point in time. We use
54 * this to simplify memory management in this driver - we cache and process
55 * only one message at a time.
56 *
57 * While the request/response protocol is guaranteed by the host, we further
58 * ensure this by serializing packet processing in this driver - we do not
59 * read additional packets from the VMBUs until the current packet is fully
60 * handled.
61 */
62
63static struct {
64 int state; /* hvutil_device_state */
65 int recv_len; /* number of bytes received. */
66 struct hv_kvp_msg *kvp_msg; /* current message */
67 struct vmbus_channel *recv_channel; /* chn we got the request */
68 u64 recv_req_id; /* request ID. */
69} kvp_transaction;
70
71/*
72 * This state maintains the version number registered by the daemon.
73 */
74static int dm_reg_value;
75
76static void kvp_send_key(struct work_struct *dummy);
77
78
79static void kvp_respond_to_host(struct hv_kvp_msg *msg, int error);
80static void kvp_timeout_func(struct work_struct *dummy);
81static void kvp_register(int);
82
83static DECLARE_DELAYED_WORK(kvp_timeout_work, kvp_timeout_func);
84static DECLARE_WORK(kvp_sendkey_work, kvp_send_key);
85
86static const char kvp_devname[] = "vmbus/hv_kvp";
87static u8 *recv_buffer;
88static struct hvutil_transport *hvt;
89/*
90 * Register the kernel component with the user-level daemon.
91 * As part of this registration, pass the LIC version number.
92 * This number has no meaning, it satisfies the registration protocol.
93 */
94#define HV_DRV_VERSION "3.1"
95
96static void kvp_poll_wrapper(void *channel)
97{
98 /* Transaction is finished, reset the state here to avoid races. */
99 kvp_transaction.state = HVUTIL_READY;
100 hv_kvp_onchannelcallback(channel);
101}
102
103static void
104kvp_register(int reg_value)
105{
106
107 struct hv_kvp_msg *kvp_msg;
108 char *version;
109
110 kvp_msg = kzalloc(sizeof(*kvp_msg), GFP_KERNEL);
111
112 if (kvp_msg) {
113 version = kvp_msg->body.kvp_register.version;
114 kvp_msg->kvp_hdr.operation = reg_value;
115 strcpy(version, HV_DRV_VERSION);
116
117 hvutil_transport_send(hvt, kvp_msg, sizeof(*kvp_msg));
118 kfree(kvp_msg);
119 }
120}
121
122static void kvp_timeout_func(struct work_struct *dummy)
123{
124 /*
125 * If the timer fires, the user-mode component has not responded;
126 * process the pending transaction.
127 */
128 kvp_respond_to_host(NULL, HV_E_FAIL);
129
130 hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper);
131}
132
133static int kvp_handle_handshake(struct hv_kvp_msg *msg)
134{
135 switch (msg->kvp_hdr.operation) {
136 case KVP_OP_REGISTER:
137 dm_reg_value = KVP_OP_REGISTER;
138 pr_info("KVP: IP injection functionality not available\n");
139 pr_info("KVP: Upgrade the KVP daemon\n");
140 break;
141 case KVP_OP_REGISTER1:
142 dm_reg_value = KVP_OP_REGISTER1;
143 break;
144 default:
145 pr_info("KVP: incompatible daemon\n");
146 pr_info("KVP: KVP version: %d, Daemon version: %d\n",
147 KVP_OP_REGISTER1, msg->kvp_hdr.operation);
148 return -EINVAL;
149 }
150
151 /*
152 * We have a compatible daemon; complete the handshake.
153 */
154 pr_debug("KVP: userspace daemon ver. %d registered\n",
155 KVP_OP_REGISTER);
156 kvp_register(dm_reg_value);
157 hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper);
158
159 return 0;
160}
161
162
163/*
164 * Callback when data is received from user mode.
165 */
166
167static int kvp_on_msg(void *msg, int len)
168{
169 struct hv_kvp_msg *message = (struct hv_kvp_msg *)msg;
170 struct hv_kvp_msg_enumerate *data;
171 int error = 0;
172
173 if (len < sizeof(*message))
174 return -EINVAL;
175
176 /*
177 * If we are negotiating the version information
178 * with the daemon; handle that first.
179 */
180
181 if (kvp_transaction.state < HVUTIL_READY) {
182 return kvp_handle_handshake(message);
183 }
184
185 /* We didn't send anything to userspace so the reply is spurious */
186 if (kvp_transaction.state < HVUTIL_USERSPACE_REQ)
187 return -EINVAL;
188
189 kvp_transaction.state = HVUTIL_USERSPACE_RECV;
190
191 /*
192 * Based on the version of the daemon, we propagate errors from the
193 * daemon differently.
194 */
195
196 data = &message->body.kvp_enum_data;
197
198 switch (dm_reg_value) {
199 case KVP_OP_REGISTER:
200 /*
201 * Null string is used to pass back error condition.
202 */
203 if (data->data.key[0] == 0)
204 error = HV_S_CONT;
205 break;
206
207 case KVP_OP_REGISTER1:
208 /*
209 * We use the message header information from
210 * the user level daemon to transmit errors.
211 */
212 error = message->error;
213 break;
214 }
215
216 /*
217 * Complete the transaction by forwarding the key value
218 * to the host. But first, cancel the timeout.
219 */
220 if (cancel_delayed_work_sync(&kvp_timeout_work)) {
221 kvp_respond_to_host(message, error);
222 hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper);
223 }
224
225 return 0;
226}
227
228
229static int process_ob_ipinfo(void *in_msg, void *out_msg, int op)
230{
231 struct hv_kvp_msg *in = in_msg;
232 struct hv_kvp_ip_msg *out = out_msg;
233 int len;
234
235 switch (op) {
236 case KVP_OP_GET_IP_INFO:
237 /*
238 * Transform all parameters into utf16 encoding.
239 */
240 len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.ip_addr,
241 strlen((char *)in->body.kvp_ip_val.ip_addr),
242 UTF16_HOST_ENDIAN,
243 (wchar_t *)out->kvp_ip_val.ip_addr,
244 MAX_IP_ADDR_SIZE);
245 if (len < 0)
246 return len;
247
248 len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.sub_net,
249 strlen((char *)in->body.kvp_ip_val.sub_net),
250 UTF16_HOST_ENDIAN,
251 (wchar_t *)out->kvp_ip_val.sub_net,
252 MAX_IP_ADDR_SIZE);
253 if (len < 0)
254 return len;
255
256 len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.gate_way,
257 strlen((char *)in->body.kvp_ip_val.gate_way),
258 UTF16_HOST_ENDIAN,
259 (wchar_t *)out->kvp_ip_val.gate_way,
260 MAX_GATEWAY_SIZE);
261 if (len < 0)
262 return len;
263
264 len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.dns_addr,
265 strlen((char *)in->body.kvp_ip_val.dns_addr),
266 UTF16_HOST_ENDIAN,
267 (wchar_t *)out->kvp_ip_val.dns_addr,
268 MAX_IP_ADDR_SIZE);
269 if (len < 0)
270 return len;
271
272 len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.adapter_id,
273 strlen((char *)in->body.kvp_ip_val.adapter_id),
274 UTF16_HOST_ENDIAN,
275 (wchar_t *)out->kvp_ip_val.adapter_id,
276 MAX_IP_ADDR_SIZE);
277 if (len < 0)
278 return len;
279
280 out->kvp_ip_val.dhcp_enabled =
281 in->body.kvp_ip_val.dhcp_enabled;
282 out->kvp_ip_val.addr_family =
283 in->body.kvp_ip_val.addr_family;
284 }
285
286 return 0;
287}
288
289static void process_ib_ipinfo(void *in_msg, void *out_msg, int op)
290{
291 struct hv_kvp_ip_msg *in = in_msg;
292 struct hv_kvp_msg *out = out_msg;
293
294 switch (op) {
295 case KVP_OP_SET_IP_INFO:
296 /*
297 * Transform all parameters into utf8 encoding.
298 */
299 utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.ip_addr,
300 MAX_IP_ADDR_SIZE,
301 UTF16_LITTLE_ENDIAN,
302 (__u8 *)out->body.kvp_ip_val.ip_addr,
303 MAX_IP_ADDR_SIZE);
304
305 utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.sub_net,
306 MAX_IP_ADDR_SIZE,
307 UTF16_LITTLE_ENDIAN,
308 (__u8 *)out->body.kvp_ip_val.sub_net,
309 MAX_IP_ADDR_SIZE);
310
311 utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.gate_way,
312 MAX_GATEWAY_SIZE,
313 UTF16_LITTLE_ENDIAN,
314 (__u8 *)out->body.kvp_ip_val.gate_way,
315 MAX_GATEWAY_SIZE);
316
317 utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.dns_addr,
318 MAX_IP_ADDR_SIZE,
319 UTF16_LITTLE_ENDIAN,
320 (__u8 *)out->body.kvp_ip_val.dns_addr,
321 MAX_IP_ADDR_SIZE);
322
323 out->body.kvp_ip_val.dhcp_enabled = in->kvp_ip_val.dhcp_enabled;
324
325 default:
326 utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.adapter_id,
327 MAX_ADAPTER_ID_SIZE,
328 UTF16_LITTLE_ENDIAN,
329 (__u8 *)out->body.kvp_ip_val.adapter_id,
330 MAX_ADAPTER_ID_SIZE);
331
332 out->body.kvp_ip_val.addr_family = in->kvp_ip_val.addr_family;
333 }
334}
335
336
337
338
339static void
340kvp_send_key(struct work_struct *dummy)
341{
342 struct hv_kvp_msg *message;
343 struct hv_kvp_msg *in_msg;
344 __u8 operation = kvp_transaction.kvp_msg->kvp_hdr.operation;
345 __u8 pool = kvp_transaction.kvp_msg->kvp_hdr.pool;
346 __u32 val32;
347 __u64 val64;
348 int rc;
349
350 /* The transaction state is wrong. */
351 if (kvp_transaction.state != HVUTIL_HOSTMSG_RECEIVED)
352 return;
353
354 message = kzalloc(sizeof(*message), GFP_KERNEL);
355 if (!message)
356 return;
357
358 message->kvp_hdr.operation = operation;
359 message->kvp_hdr.pool = pool;
360 in_msg = kvp_transaction.kvp_msg;
361
362 /*
363 * The key/value strings sent from the host are encoded in
364 * in utf16; convert it to utf8 strings.
365 * The host assures us that the utf16 strings will not exceed
366 * the max lengths specified. We will however, reserve room
367 * for the string terminating character - in the utf16s_utf8s()
368 * function we limit the size of the buffer where the converted
369 * string is placed to HV_KVP_EXCHANGE_MAX_*_SIZE -1 to gaurantee
370 * that the strings can be properly terminated!
371 */
372
373 switch (message->kvp_hdr.operation) {
374 case KVP_OP_SET_IP_INFO:
375 process_ib_ipinfo(in_msg, message, KVP_OP_SET_IP_INFO);
376 break;
377 case KVP_OP_GET_IP_INFO:
378 process_ib_ipinfo(in_msg, message, KVP_OP_GET_IP_INFO);
379 break;
380 case KVP_OP_SET:
381 switch (in_msg->body.kvp_set.data.value_type) {
382 case REG_SZ:
383 /*
384 * The value is a string - utf16 encoding.
385 */
386 message->body.kvp_set.data.value_size =
387 utf16s_to_utf8s(
388 (wchar_t *)in_msg->body.kvp_set.data.value,
389 in_msg->body.kvp_set.data.value_size,
390 UTF16_LITTLE_ENDIAN,
391 message->body.kvp_set.data.value,
392 HV_KVP_EXCHANGE_MAX_VALUE_SIZE - 1) + 1;
393 break;
394
395 case REG_U32:
396 /*
397 * The value is a 32 bit scalar.
398 * We save this as a utf8 string.
399 */
400 val32 = in_msg->body.kvp_set.data.value_u32;
401 message->body.kvp_set.data.value_size =
402 sprintf(message->body.kvp_set.data.value,
403 "%d", val32) + 1;
404 break;
405
406 case REG_U64:
407 /*
408 * The value is a 64 bit scalar.
409 * We save this as a utf8 string.
410 */
411 val64 = in_msg->body.kvp_set.data.value_u64;
412 message->body.kvp_set.data.value_size =
413 sprintf(message->body.kvp_set.data.value,
414 "%llu", val64) + 1;
415 break;
416
417 }
418 case KVP_OP_GET:
419 message->body.kvp_set.data.key_size =
420 utf16s_to_utf8s(
421 (wchar_t *)in_msg->body.kvp_set.data.key,
422 in_msg->body.kvp_set.data.key_size,
423 UTF16_LITTLE_ENDIAN,
424 message->body.kvp_set.data.key,
425 HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1) + 1;
426 break;
427
428 case KVP_OP_DELETE:
429 message->body.kvp_delete.key_size =
430 utf16s_to_utf8s(
431 (wchar_t *)in_msg->body.kvp_delete.key,
432 in_msg->body.kvp_delete.key_size,
433 UTF16_LITTLE_ENDIAN,
434 message->body.kvp_delete.key,
435 HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1) + 1;
436 break;
437
438 case KVP_OP_ENUMERATE:
439 message->body.kvp_enum_data.index =
440 in_msg->body.kvp_enum_data.index;
441 break;
442 }
443
444 kvp_transaction.state = HVUTIL_USERSPACE_REQ;
445 rc = hvutil_transport_send(hvt, message, sizeof(*message));
446 if (rc) {
447 pr_debug("KVP: failed to communicate to the daemon: %d\n", rc);
448 if (cancel_delayed_work_sync(&kvp_timeout_work)) {
449 kvp_respond_to_host(message, HV_E_FAIL);
450 kvp_transaction.state = HVUTIL_READY;
451 }
452 }
453
454 kfree(message);
455
456 return;
457}
458
459/*
460 * Send a response back to the host.
461 */
462
463static void
464kvp_respond_to_host(struct hv_kvp_msg *msg_to_host, int error)
465{
466 struct hv_kvp_msg *kvp_msg;
467 struct hv_kvp_exchg_msg_value *kvp_data;
468 char *key_name;
469 char *value;
470 struct icmsg_hdr *icmsghdrp;
471 int keylen = 0;
472 int valuelen = 0;
473 u32 buf_len;
474 struct vmbus_channel *channel;
475 u64 req_id;
476 int ret;
477
478 /*
479 * Copy the global state for completing the transaction. Note that
480 * only one transaction can be active at a time.
481 */
482
483 buf_len = kvp_transaction.recv_len;
484 channel = kvp_transaction.recv_channel;
485 req_id = kvp_transaction.recv_req_id;
486
487 icmsghdrp = (struct icmsg_hdr *)
488 &recv_buffer[sizeof(struct vmbuspipe_hdr)];
489
490 if (channel->onchannel_callback == NULL)
491 /*
492 * We have raced with util driver being unloaded;
493 * silently return.
494 */
495 return;
496
497 icmsghdrp->status = error;
498
499 /*
500 * If the error parameter is set, terminate the host's enumeration
501 * on this pool.
502 */
503 if (error) {
504 /*
505 * Something failed or we have timedout;
506 * terminate the current host-side iteration.
507 */
508 goto response_done;
509 }
510
511 kvp_msg = (struct hv_kvp_msg *)
512 &recv_buffer[sizeof(struct vmbuspipe_hdr) +
513 sizeof(struct icmsg_hdr)];
514
515 switch (kvp_transaction.kvp_msg->kvp_hdr.operation) {
516 case KVP_OP_GET_IP_INFO:
517 ret = process_ob_ipinfo(msg_to_host,
518 (struct hv_kvp_ip_msg *)kvp_msg,
519 KVP_OP_GET_IP_INFO);
520 if (ret < 0)
521 icmsghdrp->status = HV_E_FAIL;
522
523 goto response_done;
524 case KVP_OP_SET_IP_INFO:
525 goto response_done;
526 case KVP_OP_GET:
527 kvp_data = &kvp_msg->body.kvp_get.data;
528 goto copy_value;
529
530 case KVP_OP_SET:
531 case KVP_OP_DELETE:
532 goto response_done;
533
534 default:
535 break;
536 }
537
538 kvp_data = &kvp_msg->body.kvp_enum_data.data;
539 key_name = msg_to_host->body.kvp_enum_data.data.key;
540
541 /*
542 * The windows host expects the key/value pair to be encoded
543 * in utf16. Ensure that the key/value size reported to the host
544 * will be less than or equal to the MAX size (including the
545 * terminating character).
546 */
547 keylen = utf8s_to_utf16s(key_name, strlen(key_name), UTF16_HOST_ENDIAN,
548 (wchar_t *) kvp_data->key,
549 (HV_KVP_EXCHANGE_MAX_KEY_SIZE / 2) - 2);
550 kvp_data->key_size = 2*(keylen + 1); /* utf16 encoding */
551
552copy_value:
553 value = msg_to_host->body.kvp_enum_data.data.value;
554 valuelen = utf8s_to_utf16s(value, strlen(value), UTF16_HOST_ENDIAN,
555 (wchar_t *) kvp_data->value,
556 (HV_KVP_EXCHANGE_MAX_VALUE_SIZE / 2) - 2);
557 kvp_data->value_size = 2*(valuelen + 1); /* utf16 encoding */
558
559 /*
560 * If the utf8s to utf16s conversion failed; notify host
561 * of the error.
562 */
563 if ((keylen < 0) || (valuelen < 0))
564 icmsghdrp->status = HV_E_FAIL;
565
566 kvp_data->value_type = REG_SZ; /* all our values are strings */
567
568response_done:
569 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
570
571 vmbus_sendpacket(channel, recv_buffer, buf_len, req_id,
572 VM_PKT_DATA_INBAND, 0);
573}
574
575/*
576 * This callback is invoked when we get a KVP message from the host.
577 * The host ensures that only one KVP transaction can be active at a time.
578 * KVP implementation in Linux needs to forward the key to a user-mde
579 * component to retrive the corresponding value. Consequently, we cannot
580 * respond to the host in the conext of this callback. Since the host
581 * guarantees that at most only one transaction can be active at a time,
582 * we stash away the transaction state in a set of global variables.
583 */
584
585void hv_kvp_onchannelcallback(void *context)
586{
587 struct vmbus_channel *channel = context;
588 u32 recvlen;
589 u64 requestid;
590
591 struct hv_kvp_msg *kvp_msg;
592
593 struct icmsg_hdr *icmsghdrp;
594 struct icmsg_negotiate *negop = NULL;
595 int util_fw_version;
596 int kvp_srv_version;
597
598 if (kvp_transaction.state > HVUTIL_READY)
599 return;
600
601 vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 4, &recvlen,
602 &requestid);
603
604 if (recvlen > 0) {
605 icmsghdrp = (struct icmsg_hdr *)&recv_buffer[
606 sizeof(struct vmbuspipe_hdr)];
607
608 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
609 /*
610 * Based on the host, select appropriate
611 * framework and service versions we will
612 * negotiate.
613 */
614 switch (vmbus_proto_version) {
615 case (VERSION_WS2008):
616 util_fw_version = UTIL_WS2K8_FW_VERSION;
617 kvp_srv_version = WS2008_SRV_VERSION;
618 break;
619 case (VERSION_WIN7):
620 util_fw_version = UTIL_FW_VERSION;
621 kvp_srv_version = WIN7_SRV_VERSION;
622 break;
623 default:
624 util_fw_version = UTIL_FW_VERSION;
625 kvp_srv_version = WIN8_SRV_VERSION;
626 }
627 vmbus_prep_negotiate_resp(icmsghdrp, negop,
628 recv_buffer, util_fw_version,
629 kvp_srv_version);
630
631 } else {
632 kvp_msg = (struct hv_kvp_msg *)&recv_buffer[
633 sizeof(struct vmbuspipe_hdr) +
634 sizeof(struct icmsg_hdr)];
635
636 /*
637 * Stash away this global state for completing the
638 * transaction; note transactions are serialized.
639 */
640
641 kvp_transaction.recv_len = recvlen;
642 kvp_transaction.recv_req_id = requestid;
643 kvp_transaction.kvp_msg = kvp_msg;
644
645 if (kvp_transaction.state < HVUTIL_READY) {
646 /* Userspace is not registered yet */
647 kvp_respond_to_host(NULL, HV_E_FAIL);
648 return;
649 }
650 kvp_transaction.state = HVUTIL_HOSTMSG_RECEIVED;
651
652 /*
653 * Get the information from the
654 * user-mode component.
655 * component. This transaction will be
656 * completed when we get the value from
657 * the user-mode component.
658 * Set a timeout to deal with
659 * user-mode not responding.
660 */
661 schedule_work(&kvp_sendkey_work);
662 schedule_delayed_work(&kvp_timeout_work,
663 HV_UTIL_TIMEOUT * HZ);
664
665 return;
666
667 }
668
669 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
670 | ICMSGHDRFLAG_RESPONSE;
671
672 vmbus_sendpacket(channel, recv_buffer,
673 recvlen, requestid,
674 VM_PKT_DATA_INBAND, 0);
675 }
676
677}
678
679static void kvp_on_reset(void)
680{
681 if (cancel_delayed_work_sync(&kvp_timeout_work))
682 kvp_respond_to_host(NULL, HV_E_FAIL);
683 kvp_transaction.state = HVUTIL_DEVICE_INIT;
684}
685
686int
687hv_kvp_init(struct hv_util_service *srv)
688{
689 recv_buffer = srv->recv_buffer;
690 kvp_transaction.recv_channel = srv->channel;
691
692 /*
693 * When this driver loads, the user level daemon that
694 * processes the host requests may not yet be running.
695 * Defer processing channel callbacks until the daemon
696 * has registered.
697 */
698 kvp_transaction.state = HVUTIL_DEVICE_INIT;
699
700 hvt = hvutil_transport_init(kvp_devname, CN_KVP_IDX, CN_KVP_VAL,
701 kvp_on_msg, kvp_on_reset);
702 if (!hvt)
703 return -EFAULT;
704
705 return 0;
706}
707
708void hv_kvp_deinit(void)
709{
710 kvp_transaction.state = HVUTIL_DEVICE_DYING;
711 cancel_delayed_work_sync(&kvp_timeout_work);
712 cancel_work_sync(&kvp_sendkey_work);
713 hvutil_transport_destroy(hvt);
714}
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}