1 // SPDX-License-Identifier: GPL-2.0
3 * Witness Service client for CIFS
5 * Copyright (c) 2020 Samuel Cabrero <scabrero@suse.de>
8 #include <linux/kref.h>
9 #include <net/genetlink.h>
10 #include <uapi/linux/cifs/cifs_netlink.h>
14 #include "cifsproto.h"
16 #include "cifs_debug.h"
19 static DEFINE_IDR(cifs_swnreg_idr);
20 static DEFINE_MUTEX(cifs_swnreg_idr_mutex);
24 struct kref ref_count;
27 const char *share_name;
29 bool share_name_notify;
32 struct cifs_tcon *tcon;
35 static int cifs_swn_auth_info_krb(struct cifs_tcon *tcon, struct sk_buff *skb)
39 ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_KRB_AUTH);
46 static int cifs_swn_auth_info_ntlm(struct cifs_tcon *tcon, struct sk_buff *skb)
50 if (tcon->ses->user_name != NULL) {
51 ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_USER_NAME, tcon->ses->user_name);
56 if (tcon->ses->password != NULL) {
57 ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_PASSWORD, tcon->ses->password);
62 if (tcon->ses->domainName != NULL) {
63 ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_DOMAIN_NAME, tcon->ses->domainName);
72 * Sends a register message to the userspace daemon based on the registration.
73 * The authentication information to connect to the witness service is bundled
76 static int cifs_swn_send_register_message(struct cifs_swn_reg *swnreg)
79 struct genlmsghdr *hdr;
80 enum securityEnum authtype;
81 struct sockaddr_storage *addr;
84 skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
90 hdr = genlmsg_put(skb, 0, 0, &cifs_genl_family, 0, CIFS_GENL_CMD_SWN_REGISTER);
96 ret = nla_put_u32(skb, CIFS_GENL_ATTR_SWN_REGISTRATION_ID, swnreg->id);
100 ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_NET_NAME, swnreg->net_name);
104 ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_SHARE_NAME, swnreg->share_name);
109 * If there is an address stored use it instead of the server address, because we are
110 * in the process of reconnecting to it after a share has been moved or we have been
111 * told to switch to it (client move message). In these cases we unregister from the
112 * server address and register to the new address when we receive the notification.
114 if (swnreg->tcon->ses->server->use_swn_dstaddr)
115 addr = &swnreg->tcon->ses->server->swn_dstaddr;
117 addr = &swnreg->tcon->ses->server->dstaddr;
119 ret = nla_put(skb, CIFS_GENL_ATTR_SWN_IP, sizeof(struct sockaddr_storage), addr);
123 if (swnreg->net_name_notify) {
124 ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_NET_NAME_NOTIFY);
129 if (swnreg->share_name_notify) {
130 ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_SHARE_NAME_NOTIFY);
135 if (swnreg->ip_notify) {
136 ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_IP_NOTIFY);
141 authtype = cifs_select_sectype(swnreg->tcon->ses->server, swnreg->tcon->ses->sectype);
144 ret = cifs_swn_auth_info_krb(swnreg->tcon, skb);
146 cifs_dbg(VFS, "%s: Failed to get kerberos auth info: %d\n", __func__, ret);
154 ret = cifs_swn_auth_info_ntlm(swnreg->tcon, skb);
156 cifs_dbg(VFS, "%s: Failed to get NTLM auth info: %d\n", __func__, ret);
161 cifs_dbg(VFS, "%s: secType %d not supported!\n", __func__, authtype);
166 genlmsg_end(skb, hdr);
167 genlmsg_multicast(&cifs_genl_family, skb, 0, CIFS_GENL_MCGRP_SWN, GFP_ATOMIC);
169 cifs_dbg(FYI, "%s: Message to register for network name %s with id %d sent\n", __func__,
170 swnreg->net_name, swnreg->id);
175 genlmsg_cancel(skb, hdr);
182 * Sends an uregister message to the userspace daemon based on the registration
184 static int cifs_swn_send_unregister_message(struct cifs_swn_reg *swnreg)
187 struct genlmsghdr *hdr;
190 skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
194 hdr = genlmsg_put(skb, 0, 0, &cifs_genl_family, 0, CIFS_GENL_CMD_SWN_UNREGISTER);
200 ret = nla_put_u32(skb, CIFS_GENL_ATTR_SWN_REGISTRATION_ID, swnreg->id);
204 ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_NET_NAME, swnreg->net_name);
208 ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_SHARE_NAME, swnreg->share_name);
212 ret = nla_put(skb, CIFS_GENL_ATTR_SWN_IP, sizeof(struct sockaddr_storage),
213 &swnreg->tcon->ses->server->dstaddr);
217 if (swnreg->net_name_notify) {
218 ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_NET_NAME_NOTIFY);
223 if (swnreg->share_name_notify) {
224 ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_SHARE_NAME_NOTIFY);
229 if (swnreg->ip_notify) {
230 ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_IP_NOTIFY);
235 genlmsg_end(skb, hdr);
236 genlmsg_multicast(&cifs_genl_family, skb, 0, CIFS_GENL_MCGRP_SWN, GFP_ATOMIC);
238 cifs_dbg(FYI, "%s: Message to unregister for network name %s with id %d sent\n", __func__,
239 swnreg->net_name, swnreg->id);
244 genlmsg_cancel(skb, hdr);
250 * Try to find a matching registration for the tcon's server name and share name.
251 * Calls to this funciton must be protected by cifs_swnreg_idr_mutex.
252 * TODO Try to avoid memory allocations
254 static struct cifs_swn_reg *cifs_find_swn_reg(struct cifs_tcon *tcon)
256 struct cifs_swn_reg *swnreg;
258 const char *share_name;
259 const char *net_name;
261 net_name = extract_hostname(tcon->treeName);
262 if (IS_ERR(net_name)) {
265 ret = PTR_ERR(net_name);
266 cifs_dbg(VFS, "%s: failed to extract host name from target '%s': %d\n",
267 __func__, tcon->treeName, ret);
268 return ERR_PTR(-EINVAL);
271 share_name = extract_sharename(tcon->treeName);
272 if (IS_ERR(share_name)) {
275 ret = PTR_ERR(net_name);
276 cifs_dbg(VFS, "%s: failed to extract share name from target '%s': %d\n",
277 __func__, tcon->treeName, ret);
279 return ERR_PTR(-EINVAL);
282 idr_for_each_entry(&cifs_swnreg_idr, swnreg, id) {
283 if (strcasecmp(swnreg->net_name, net_name) != 0
284 || strcasecmp(swnreg->share_name, share_name) != 0) {
288 mutex_unlock(&cifs_swnreg_idr_mutex);
290 cifs_dbg(FYI, "Existing swn registration for %s:%s found\n", swnreg->net_name,
302 return ERR_PTR(-EEXIST);
306 * Get a registration for the tcon's server and share name, allocating a new one if it does not
309 static struct cifs_swn_reg *cifs_get_swn_reg(struct cifs_tcon *tcon)
311 struct cifs_swn_reg *reg = NULL;
314 mutex_lock(&cifs_swnreg_idr_mutex);
316 /* Check if we are already registered for this network and share names */
317 reg = cifs_find_swn_reg(tcon);
319 kref_get(®->ref_count);
320 mutex_unlock(&cifs_swnreg_idr_mutex);
322 } else if (PTR_ERR(reg) != -EEXIST) {
323 mutex_unlock(&cifs_swnreg_idr_mutex);
327 reg = kmalloc(sizeof(struct cifs_swn_reg), GFP_ATOMIC);
329 mutex_unlock(&cifs_swnreg_idr_mutex);
330 return ERR_PTR(-ENOMEM);
333 kref_init(®->ref_count);
335 reg->id = idr_alloc(&cifs_swnreg_idr, reg, 1, 0, GFP_ATOMIC);
337 cifs_dbg(FYI, "%s: failed to allocate registration id\n", __func__);
342 reg->net_name = extract_hostname(tcon->treeName);
343 if (IS_ERR(reg->net_name)) {
344 ret = PTR_ERR(reg->net_name);
345 cifs_dbg(VFS, "%s: failed to extract host name from target: %d\n", __func__, ret);
349 reg->share_name = extract_sharename(tcon->treeName);
350 if (IS_ERR(reg->share_name)) {
351 ret = PTR_ERR(reg->share_name);
352 cifs_dbg(VFS, "%s: failed to extract share name from target: %d\n", __func__, ret);
356 reg->net_name_notify = true;
357 reg->share_name_notify = true;
358 reg->ip_notify = (tcon->capabilities & SMB2_SHARE_CAP_SCALEOUT);
362 mutex_unlock(&cifs_swnreg_idr_mutex);
367 kfree(reg->net_name);
369 idr_remove(&cifs_swnreg_idr, reg->id);
372 mutex_unlock(&cifs_swnreg_idr_mutex);
376 static void cifs_swn_reg_release(struct kref *ref)
378 struct cifs_swn_reg *swnreg = container_of(ref, struct cifs_swn_reg, ref_count);
381 ret = cifs_swn_send_unregister_message(swnreg);
383 cifs_dbg(VFS, "%s: Failed to send unregister message: %d\n", __func__, ret);
385 idr_remove(&cifs_swnreg_idr, swnreg->id);
386 kfree(swnreg->net_name);
387 kfree(swnreg->share_name);
391 static void cifs_put_swn_reg(struct cifs_swn_reg *swnreg)
393 mutex_lock(&cifs_swnreg_idr_mutex);
394 kref_put(&swnreg->ref_count, cifs_swn_reg_release);
395 mutex_unlock(&cifs_swnreg_idr_mutex);
398 static int cifs_swn_resource_state_changed(struct cifs_swn_reg *swnreg, const char *name, int state)
403 case CIFS_SWN_RESOURCE_STATE_UNAVAILABLE:
404 cifs_dbg(FYI, "%s: resource name '%s' become unavailable\n", __func__, name);
405 for (i = 0; i < swnreg->tcon->ses->chan_count; i++) {
406 spin_lock(&GlobalMid_Lock);
407 if (swnreg->tcon->ses->chans[i].server->tcpStatus != CifsExiting)
408 swnreg->tcon->ses->chans[i].server->tcpStatus = CifsNeedReconnect;
409 spin_unlock(&GlobalMid_Lock);
412 case CIFS_SWN_RESOURCE_STATE_AVAILABLE:
413 cifs_dbg(FYI, "%s: resource name '%s' become available\n", __func__, name);
414 for (i = 0; i < swnreg->tcon->ses->chan_count; i++) {
415 spin_lock(&GlobalMid_Lock);
416 if (swnreg->tcon->ses->chans[i].server->tcpStatus != CifsExiting)
417 swnreg->tcon->ses->chans[i].server->tcpStatus = CifsNeedReconnect;
418 spin_unlock(&GlobalMid_Lock);
421 case CIFS_SWN_RESOURCE_STATE_UNKNOWN:
422 cifs_dbg(FYI, "%s: resource name '%s' changed to unknown state\n", __func__, name);
428 static bool cifs_sockaddr_equal(struct sockaddr_storage *addr1, struct sockaddr_storage *addr2)
430 if (addr1->ss_family != addr2->ss_family)
433 if (addr1->ss_family == AF_INET) {
434 return (memcmp(&((const struct sockaddr_in *)addr1)->sin_addr,
435 &((const struct sockaddr_in *)addr2)->sin_addr,
436 sizeof(struct in_addr)) == 0);
439 if (addr1->ss_family == AF_INET6) {
440 return (memcmp(&((const struct sockaddr_in6 *)addr1)->sin6_addr,
441 &((const struct sockaddr_in6 *)addr2)->sin6_addr,
442 sizeof(struct in6_addr)) == 0);
448 static int cifs_swn_store_swn_addr(const struct sockaddr_storage *new,
449 const struct sockaddr_storage *old,
450 struct sockaddr_storage *dst)
454 if (old->ss_family == AF_INET) {
455 struct sockaddr_in *ipv4 = (struct sockaddr_in *)old;
457 port = ipv4->sin_port;
460 if (old->ss_family == AF_INET6) {
461 struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)old;
463 port = ipv6->sin6_port;
466 if (new->ss_family == AF_INET) {
467 struct sockaddr_in *ipv4 = (struct sockaddr_in *)new;
469 ipv4->sin_port = port;
472 if (new->ss_family == AF_INET6) {
473 struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)new;
475 ipv6->sin6_port = port;
483 static int cifs_swn_reconnect(struct cifs_tcon *tcon, struct sockaddr_storage *addr)
485 /* Store the reconnect address */
486 mutex_lock(&tcon->ses->server->srv_mutex);
487 if (!cifs_sockaddr_equal(&tcon->ses->server->dstaddr, addr)) {
490 ret = cifs_swn_store_swn_addr(addr, &tcon->ses->server->dstaddr,
491 &tcon->ses->server->swn_dstaddr);
493 cifs_dbg(VFS, "%s: failed to store address: %d\n", __func__, ret);
496 tcon->ses->server->use_swn_dstaddr = true;
499 * Unregister to stop receiving notifications for the old IP address.
501 ret = cifs_swn_unregister(tcon);
503 cifs_dbg(VFS, "%s: Failed to unregister for witness notifications: %d\n",
509 * And register to receive notifications for the new IP address now that we have
510 * stored the new address.
512 ret = cifs_swn_register(tcon);
514 cifs_dbg(VFS, "%s: Failed to register for witness notifications: %d\n",
519 spin_lock(&GlobalMid_Lock);
520 if (tcon->ses->server->tcpStatus != CifsExiting)
521 tcon->ses->server->tcpStatus = CifsNeedReconnect;
522 spin_unlock(&GlobalMid_Lock);
524 mutex_unlock(&tcon->ses->server->srv_mutex);
529 static int cifs_swn_client_move(struct cifs_swn_reg *swnreg, struct sockaddr_storage *addr)
531 struct sockaddr_in *ipv4 = (struct sockaddr_in *)addr;
532 struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)addr;
534 if (addr->ss_family == AF_INET)
535 cifs_dbg(FYI, "%s: move to %pI4\n", __func__, &ipv4->sin_addr);
536 else if (addr->ss_family == AF_INET6)
537 cifs_dbg(FYI, "%s: move to %pI6\n", __func__, &ipv6->sin6_addr);
539 return cifs_swn_reconnect(swnreg->tcon, addr);
542 int cifs_swn_notify(struct sk_buff *skb, struct genl_info *info)
544 struct cifs_swn_reg *swnreg;
548 if (info->attrs[CIFS_GENL_ATTR_SWN_REGISTRATION_ID]) {
551 swnreg_id = nla_get_u32(info->attrs[CIFS_GENL_ATTR_SWN_REGISTRATION_ID]);
552 mutex_lock(&cifs_swnreg_idr_mutex);
553 swnreg = idr_find(&cifs_swnreg_idr, swnreg_id);
554 mutex_unlock(&cifs_swnreg_idr_mutex);
555 if (swnreg == NULL) {
556 cifs_dbg(FYI, "%s: registration id %d not found\n", __func__, swnreg_id);
560 cifs_dbg(FYI, "%s: missing registration id attribute\n", __func__);
564 if (info->attrs[CIFS_GENL_ATTR_SWN_NOTIFICATION_TYPE]) {
565 type = nla_get_u32(info->attrs[CIFS_GENL_ATTR_SWN_NOTIFICATION_TYPE]);
567 cifs_dbg(FYI, "%s: missing notification type attribute\n", __func__);
572 case CIFS_SWN_NOTIFICATION_RESOURCE_CHANGE: {
575 if (info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_NAME]) {
576 nla_strscpy(name, info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_NAME],
579 cifs_dbg(FYI, "%s: missing resource name attribute\n", __func__);
582 if (info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_STATE]) {
583 state = nla_get_u32(info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_STATE]);
585 cifs_dbg(FYI, "%s: missing resource state attribute\n", __func__);
588 return cifs_swn_resource_state_changed(swnreg, name, state);
590 case CIFS_SWN_NOTIFICATION_CLIENT_MOVE: {
591 struct sockaddr_storage addr;
593 if (info->attrs[CIFS_GENL_ATTR_SWN_IP]) {
594 nla_memcpy(&addr, info->attrs[CIFS_GENL_ATTR_SWN_IP], sizeof(addr));
596 cifs_dbg(FYI, "%s: missing IP address attribute\n", __func__);
599 return cifs_swn_client_move(swnreg, &addr);
602 cifs_dbg(FYI, "%s: unknown notification type %d\n", __func__, type);
609 int cifs_swn_register(struct cifs_tcon *tcon)
611 struct cifs_swn_reg *swnreg;
614 swnreg = cifs_get_swn_reg(tcon);
616 return PTR_ERR(swnreg);
618 ret = cifs_swn_send_register_message(swnreg);
620 cifs_dbg(VFS, "%s: Failed to send swn register message: %d\n", __func__, ret);
621 /* Do not put the swnreg or return error, the echo task will retry */
627 int cifs_swn_unregister(struct cifs_tcon *tcon)
629 struct cifs_swn_reg *swnreg;
631 mutex_lock(&cifs_swnreg_idr_mutex);
633 swnreg = cifs_find_swn_reg(tcon);
634 if (IS_ERR(swnreg)) {
635 mutex_unlock(&cifs_swnreg_idr_mutex);
636 return PTR_ERR(swnreg);
639 mutex_unlock(&cifs_swnreg_idr_mutex);
641 cifs_put_swn_reg(swnreg);
646 void cifs_swn_dump(struct seq_file *m)
648 struct cifs_swn_reg *swnreg;
649 struct sockaddr_in *sa;
650 struct sockaddr_in6 *sa6;
653 seq_puts(m, "Witness registrations:");
655 mutex_lock(&cifs_swnreg_idr_mutex);
656 idr_for_each_entry(&cifs_swnreg_idr, swnreg, id) {
657 seq_printf(m, "\nId: %u Refs: %u Network name: '%s'%s Share name: '%s'%s Ip address: ",
658 id, kref_read(&swnreg->ref_count),
659 swnreg->net_name, swnreg->net_name_notify ? "(y)" : "(n)",
660 swnreg->share_name, swnreg->share_name_notify ? "(y)" : "(n)");
661 switch (swnreg->tcon->ses->server->dstaddr.ss_family) {
663 sa = (struct sockaddr_in *) &swnreg->tcon->ses->server->dstaddr;
664 seq_printf(m, "%pI4", &sa->sin_addr.s_addr);
667 sa6 = (struct sockaddr_in6 *) &swnreg->tcon->ses->server->dstaddr;
668 seq_printf(m, "%pI6", &sa6->sin6_addr.s6_addr);
669 if (sa6->sin6_scope_id)
670 seq_printf(m, "%%%u", sa6->sin6_scope_id);
673 seq_puts(m, "(unknown)");
675 seq_printf(m, "%s", swnreg->ip_notify ? "(y)" : "(n)");
677 mutex_unlock(&cifs_swnreg_idr_mutex);
681 void cifs_swn_check(void)
683 struct cifs_swn_reg *swnreg;
687 mutex_lock(&cifs_swnreg_idr_mutex);
688 idr_for_each_entry(&cifs_swnreg_idr, swnreg, id) {
689 ret = cifs_swn_send_register_message(swnreg);
691 cifs_dbg(FYI, "%s: Failed to send register message: %d\n", __func__, ret);
693 mutex_unlock(&cifs_swnreg_idr_mutex);