[linux-block.git] / fs / cifs / cifs_swn.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Witness Service client for CIFS
 *
 * Copyright (c) 2020 Samuel Cabrero <scabrero@suse.de>
 */

#include <linux/kref.h>
#include <net/genetlink.h>
#include <uapi/linux/cifs/cifs_netlink.h>

#include "cifs_swn.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "fscache.h"
#include "cifs_debug.h"
#include "netlink.h"

static DEFINE_IDR(cifs_swnreg_idr);
static DEFINE_MUTEX(cifs_swnreg_idr_mutex);

struct cifs_swn_reg {
	int id;
	struct kref ref_count;

	const char *net_name;
	const char *share_name;
	bool net_name_notify;
	bool share_name_notify;
	bool ip_notify;

	struct cifs_tcon *tcon;
};

static int cifs_swn_auth_info_krb(struct cifs_tcon *tcon, struct sk_buff *skb)
{
	int ret;

	ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_KRB_AUTH);
	if (ret < 0)
		return ret;

	return 0;
}

static int cifs_swn_auth_info_ntlm(struct cifs_tcon *tcon, struct sk_buff *skb)
{
	int ret;

	if (tcon->ses->user_name != NULL) {
		ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_USER_NAME, tcon->ses->user_name);
		if (ret < 0)
			return ret;
	}

	if (tcon->ses->password != NULL) {
		ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_PASSWORD, tcon->ses->password);
		if (ret < 0)
			return ret;
	}

	if (tcon->ses->domainName != NULL) {
		ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_DOMAIN_NAME, tcon->ses->domainName);
		if (ret < 0)
			return ret;
	}

	return 0;
}

/*
 * Sends a register message to the userspace daemon based on the registration.
 * The authentication information to connect to the witness service is bundled
 * into the message.
 */
static int cifs_swn_send_register_message(struct cifs_swn_reg *swnreg)
{
	struct sk_buff *skb;
	struct genlmsghdr *hdr;
	enum securityEnum authtype;
	int ret;

	skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
	if (skb == NULL) {
		ret = -ENOMEM;
		goto fail;
	}

	hdr = genlmsg_put(skb, 0, 0, &cifs_genl_family, 0, CIFS_GENL_CMD_SWN_REGISTER);
	if (hdr == NULL) {
		ret = -ENOMEM;
		goto nlmsg_fail;
	}

	ret = nla_put_u32(skb, CIFS_GENL_ATTR_SWN_REGISTRATION_ID, swnreg->id);
	if (ret < 0)
		goto nlmsg_fail;

	ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_NET_NAME, swnreg->net_name);
	if (ret < 0)
		goto nlmsg_fail;

	ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_SHARE_NAME, swnreg->share_name);
	if (ret < 0)
		goto nlmsg_fail;

	ret = nla_put(skb, CIFS_GENL_ATTR_SWN_IP, sizeof(struct sockaddr_storage),
			&swnreg->tcon->ses->server->dstaddr);
	if (ret < 0)
		goto nlmsg_fail;

	if (swnreg->net_name_notify) {
		ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_NET_NAME_NOTIFY);
		if (ret < 0)
			goto nlmsg_fail;
	}

	if (swnreg->share_name_notify) {
		ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_SHARE_NAME_NOTIFY);
		if (ret < 0)
			goto nlmsg_fail;
	}

	if (swnreg->ip_notify) {
		ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_IP_NOTIFY);
		if (ret < 0)
			goto nlmsg_fail;
	}

	authtype = cifs_select_sectype(swnreg->tcon->ses->server, swnreg->tcon->ses->sectype);
	switch (authtype) {
	case Kerberos:
		ret = cifs_swn_auth_info_krb(swnreg->tcon, skb);
		if (ret < 0) {
			cifs_dbg(VFS, "%s: Failed to get kerberos auth info: %d\n", __func__, ret);
			goto nlmsg_fail;
		}
		break;
	case LANMAN:
	case NTLM:
	case NTLMv2:
	case RawNTLMSSP:
		ret = cifs_swn_auth_info_ntlm(swnreg->tcon, skb);
		if (ret < 0) {
			cifs_dbg(VFS, "%s: Failed to get NTLM auth info: %d\n", __func__, ret);
			goto nlmsg_fail;
		}
		break;
	default:
		cifs_dbg(VFS, "%s: secType %d not supported!\n", __func__, authtype);
		ret = -EINVAL;
		goto nlmsg_fail;
	}

	genlmsg_end(skb, hdr);
	genlmsg_multicast(&cifs_genl_family, skb, 0, CIFS_GENL_MCGRP_SWN, GFP_ATOMIC);

	cifs_dbg(FYI, "%s: Message to register for network name %s with id %d sent\n", __func__,
			swnreg->net_name, swnreg->id);

	return 0;

nlmsg_fail:
	genlmsg_cancel(skb, hdr);
	nlmsg_free(skb);
fail:
	return ret;
}

/*
 * Sends an uregister message to the userspace daemon based on the registration
 */
static int cifs_swn_send_unregister_message(struct cifs_swn_reg *swnreg)
{
	struct sk_buff *skb;
	struct genlmsghdr *hdr;
	int ret;

	skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
	if (skb == NULL)
		return -ENOMEM;

	hdr = genlmsg_put(skb, 0, 0, &cifs_genl_family, 0, CIFS_GENL_CMD_SWN_UNREGISTER);
	if (hdr == NULL) {
		ret = -ENOMEM;
		goto nlmsg_fail;
	}

	ret = nla_put_u32(skb, CIFS_GENL_ATTR_SWN_REGISTRATION_ID, swnreg->id);
	if (ret < 0)
		goto nlmsg_fail;

	ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_NET_NAME, swnreg->net_name);
	if (ret < 0)
		goto nlmsg_fail;

	ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_SHARE_NAME, swnreg->share_name);
	if (ret < 0)
		goto nlmsg_fail;

	ret = nla_put(skb, CIFS_GENL_ATTR_SWN_IP, sizeof(struct sockaddr_storage),
			&swnreg->tcon->ses->server->dstaddr);
	if (ret < 0)
		goto nlmsg_fail;

	if (swnreg->net_name_notify) {
		ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_NET_NAME_NOTIFY);
		if (ret < 0)
			goto nlmsg_fail;
	}

	if (swnreg->share_name_notify) {
		ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_SHARE_NAME_NOTIFY);
		if (ret < 0)
			goto nlmsg_fail;
	}

	if (swnreg->ip_notify) {
		ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_IP_NOTIFY);
		if (ret < 0)
			goto nlmsg_fail;
	}

	genlmsg_end(skb, hdr);
	genlmsg_multicast(&cifs_genl_family, skb, 0, CIFS_GENL_MCGRP_SWN, GFP_ATOMIC);

	cifs_dbg(FYI, "%s: Message to unregister for network name %s with id %d sent\n", __func__,
			swnreg->net_name, swnreg->id);

	return 0;

nlmsg_fail:
	genlmsg_cancel(skb, hdr);
	nlmsg_free(skb);
	return ret;
}

/*
 * Try to find a matching registration for the tcon's server name and share name.
 * Calls to this funciton must be protected by cifs_swnreg_idr_mutex.
 * TODO Try to avoid memory allocations
 */
static struct cifs_swn_reg *cifs_find_swn_reg(struct cifs_tcon *tcon)
{
	struct cifs_swn_reg *swnreg;
	int id;
	const char *share_name;
	const char *net_name;

	net_name = extract_hostname(tcon->treeName);
	if (IS_ERR_OR_NULL(net_name)) {
		int ret;

		ret = PTR_ERR(net_name);
		cifs_dbg(VFS, "%s: failed to extract host name from target '%s': %d\n",
				__func__, tcon->treeName, ret);
		return NULL;
	}

	share_name = extract_sharename(tcon->treeName);
	if (IS_ERR_OR_NULL(share_name)) {
		int ret;

		ret = PTR_ERR(net_name);
		cifs_dbg(VFS, "%s: failed to extract share name from target '%s': %d\n",
				__func__, tcon->treeName, ret);
		kfree(net_name);
		return NULL;
	}

	idr_for_each_entry(&cifs_swnreg_idr, swnreg, id) {
		if (strcasecmp(swnreg->net_name, net_name) != 0
		    || strcasecmp(swnreg->share_name, share_name) != 0) {
			continue;
		}

		mutex_unlock(&cifs_swnreg_idr_mutex);

		cifs_dbg(FYI, "Existing swn registration for %s:%s found\n", swnreg->net_name,
				swnreg->share_name);

		kfree(net_name);
		kfree(share_name);

		return swnreg;
	}

	kfree(net_name);
	kfree(share_name);

	return NULL;
}

/*
 * Get a registration for the tcon's server and share name, allocating a new one if it does not
 * exists
 */
static struct cifs_swn_reg *cifs_get_swn_reg(struct cifs_tcon *tcon)
{
	struct cifs_swn_reg *reg = NULL;
	int ret;

	mutex_lock(&cifs_swnreg_idr_mutex);

	/* Check if we are already registered for this network and share names */
	reg = cifs_find_swn_reg(tcon);
	if (IS_ERR(reg)) {
		return reg;
	} else if (reg != NULL) {
		kref_get(&reg->ref_count);
		mutex_unlock(&cifs_swnreg_idr_mutex);
		return reg;
	}

	reg = kmalloc(sizeof(struct cifs_swn_reg), GFP_ATOMIC);
	if (reg == NULL) {
		mutex_unlock(&cifs_swnreg_idr_mutex);
		return ERR_PTR(-ENOMEM);
	}

	kref_init(&reg->ref_count);

	reg->id = idr_alloc(&cifs_swnreg_idr, reg, 1, 0, GFP_ATOMIC);
	if (reg->id < 0) {
		cifs_dbg(FYI, "%s: failed to allocate registration id\n", __func__);
		ret = reg->id;
		goto fail;
	}

	reg->net_name = extract_hostname(tcon->treeName);
	if (IS_ERR(reg->net_name)) {
		ret = PTR_ERR(reg->net_name);
		cifs_dbg(VFS, "%s: failed to extract host name from target: %d\n", __func__, ret);
		goto fail_idr;
	}

	reg->share_name = extract_sharename(tcon->treeName);
	if (IS_ERR(reg->share_name)) {
		ret = PTR_ERR(reg->share_name);
		cifs_dbg(VFS, "%s: failed to extract share name from target: %d\n", __func__, ret);
		goto fail_net_name;
	}

	reg->net_name_notify = true;
	reg->share_name_notify = true;
	reg->ip_notify = (tcon->capabilities & SMB2_SHARE_CAP_SCALEOUT);

	reg->tcon = tcon;

	mutex_unlock(&cifs_swnreg_idr_mutex);

	return reg;

fail_net_name:
	kfree(reg->net_name);
fail_idr:
	idr_remove(&cifs_swnreg_idr, reg->id);
fail:
	kfree(reg);
	mutex_unlock(&cifs_swnreg_idr_mutex);
	return ERR_PTR(ret);
}

static void cifs_swn_reg_release(struct kref *ref)
{
	struct cifs_swn_reg *swnreg = container_of(ref, struct cifs_swn_reg, ref_count);
	int ret;

	ret = cifs_swn_send_unregister_message(swnreg);
	if (ret < 0)
		cifs_dbg(VFS, "%s: Failed to send unregister message: %d\n", __func__, ret);

	idr_remove(&cifs_swnreg_idr, swnreg->id);
	kfree(swnreg->net_name);
	kfree(swnreg->share_name);
	kfree(swnreg);
}

static void cifs_put_swn_reg(struct cifs_swn_reg *swnreg)
{
	mutex_lock(&cifs_swnreg_idr_mutex);
	kref_put(&swnreg->ref_count, cifs_swn_reg_release);
	mutex_unlock(&cifs_swnreg_idr_mutex);
}

static int cifs_swn_resource_state_changed(struct cifs_swn_reg *swnreg, const char *name, int state)
{
	int i;

	switch (state) {
	case CIFS_SWN_RESOURCE_STATE_UNAVAILABLE:
		cifs_dbg(FYI, "%s: resource name '%s' become unavailable\n", __func__, name);
		for (i = 0; i < swnreg->tcon->ses->chan_count; i++) {
			spin_lock(&GlobalMid_Lock);
			if (swnreg->tcon->ses->chans[i].server->tcpStatus != CifsExiting)
				swnreg->tcon->ses->chans[i].server->tcpStatus = CifsNeedReconnect;
			spin_unlock(&GlobalMid_Lock);
		}
		break;
	case CIFS_SWN_RESOURCE_STATE_AVAILABLE:
		cifs_dbg(FYI, "%s: resource name '%s' become available\n", __func__, name);
		for (i = 0; i < swnreg->tcon->ses->chan_count; i++) {
			spin_lock(&GlobalMid_Lock);
			if (swnreg->tcon->ses->chans[i].server->tcpStatus != CifsExiting)
				swnreg->tcon->ses->chans[i].server->tcpStatus = CifsNeedReconnect;
			spin_unlock(&GlobalMid_Lock);
		}
		break;
	case CIFS_SWN_RESOURCE_STATE_UNKNOWN:
		cifs_dbg(FYI, "%s: resource name '%s' changed to unknown state\n", __func__, name);
		break;
	}
	return 0;
}

int cifs_swn_notify(struct sk_buff *skb, struct genl_info *info)
{
	struct cifs_swn_reg *swnreg;
	char name[256];
	int type;

	if (info->attrs[CIFS_GENL_ATTR_SWN_REGISTRATION_ID]) {
		int swnreg_id;

		swnreg_id = nla_get_u32(info->attrs[CIFS_GENL_ATTR_SWN_REGISTRATION_ID]);
		mutex_lock(&cifs_swnreg_idr_mutex);
		swnreg = idr_find(&cifs_swnreg_idr, swnreg_id);
		mutex_unlock(&cifs_swnreg_idr_mutex);
		if (swnreg == NULL) {
			cifs_dbg(FYI, "%s: registration id %d not found\n", __func__, swnreg_id);
			return -EINVAL;
		}
	} else {
		cifs_dbg(FYI, "%s: missing registration id attribute\n", __func__);
		return -EINVAL;
	}

	if (info->attrs[CIFS_GENL_ATTR_SWN_NOTIFICATION_TYPE]) {
		type = nla_get_u32(info->attrs[CIFS_GENL_ATTR_SWN_NOTIFICATION_TYPE]);
	} else {
		cifs_dbg(FYI, "%s: missing notification type attribute\n", __func__);
		return -EINVAL;
	}

	switch (type) {
	case CIFS_SWN_NOTIFICATION_RESOURCE_CHANGE: {
		int state;

		if (info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_NAME]) {
			nla_strlcpy(name, info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_NAME],
					sizeof(name));
		} else {
			cifs_dbg(FYI, "%s: missing resource name attribute\n", __func__);
			return -EINVAL;
		}
		if (info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_STATE]) {
			state = nla_get_u32(info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_STATE]);
		} else {
			cifs_dbg(FYI, "%s: missing resource state attribute\n", __func__);
			return -EINVAL;
		}
		return cifs_swn_resource_state_changed(swnreg, name, state);
	}
	default:
		cifs_dbg(FYI, "%s: unknown notification type %d\n", __func__, type);
		break;
	}

	return 0;
}

int cifs_swn_register(struct cifs_tcon *tcon)
{
	struct cifs_swn_reg *swnreg;
	int ret;

	swnreg = cifs_get_swn_reg(tcon);
	if (IS_ERR(swnreg))
		return PTR_ERR(swnreg);

	ret = cifs_swn_send_register_message(swnreg);
	if (ret < 0) {
		cifs_dbg(VFS, "%s: Failed to send swn register message: %d\n", __func__, ret);
		/* Do not put the swnreg or return error, the echo task will retry */
	}

	return 0;
}

int cifs_swn_unregister(struct cifs_tcon *tcon)
{
	struct cifs_swn_reg *swnreg;

	mutex_lock(&cifs_swnreg_idr_mutex);

	swnreg = cifs_find_swn_reg(tcon);
	if (swnreg == NULL) {
		mutex_unlock(&cifs_swnreg_idr_mutex);
		return -EEXIST;
	}

	mutex_unlock(&cifs_swnreg_idr_mutex);

	cifs_put_swn_reg(swnreg);

	return 0;
}

void cifs_swn_dump(struct seq_file *m)
{
	struct cifs_swn_reg *swnreg;
	struct sockaddr_in *sa;
	struct sockaddr_in6 *sa6;
	int id;

	seq_puts(m, "Witness registrations:");

	mutex_lock(&cifs_swnreg_idr_mutex);
	idr_for_each_entry(&cifs_swnreg_idr, swnreg, id) {
		seq_printf(m, "\nId: %u Refs: %u Network name: '%s'%s Share name: '%s'%s Ip address: ",
				id, kref_read(&swnreg->ref_count),
				swnreg->net_name, swnreg->net_name_notify ? "(y)" : "(n)",
				swnreg->share_name, swnreg->share_name_notify ? "(y)" : "(n)");
		switch (swnreg->tcon->ses->server->dstaddr.ss_family) {
		case AF_INET:
			sa = (struct sockaddr_in *) &swnreg->tcon->ses->server->dstaddr;
			seq_printf(m, "%pI4", &sa->sin_addr.s_addr);
			break;
		case AF_INET6:
			sa6 = (struct sockaddr_in6 *) &swnreg->tcon->ses->server->dstaddr;
			seq_printf(m, "%pI6", &sa6->sin6_addr.s6_addr);
			if (sa6->sin6_scope_id)
				seq_printf(m, "%%%u", sa6->sin6_scope_id);
			break;
		default:
			seq_puts(m, "(unknown)");
		}
		seq_printf(m, "%s", swnreg->ip_notify ? "(y)" : "(n)");
	}
	mutex_unlock(&cifs_swnreg_idr_mutex);
	seq_puts(m, "\n");
}

void cifs_swn_check(void)
{
	struct cifs_swn_reg *swnreg;
	int id;
	int ret;

	mutex_lock(&cifs_swnreg_idr_mutex);
	idr_for_each_entry(&cifs_swnreg_idr, swnreg, id) {
		ret = cifs_swn_send_register_message(swnreg);
		if (ret < 0)
			cifs_dbg(FYI, "%s: Failed to send register message: %d\n", __func__, ret);
	}
	mutex_unlock(&cifs_swnreg_idr_mutex);
}
Commit	Line	Data
bf80e5d4 SC	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	* Witness Service client for CIFS
	4	*
	5	* Copyright (c) 2020 Samuel Cabrero <scabrero@suse.de>
	6	*/
	7
	8	#include <linux/kref.h>
	9	#include <net/genetlink.h>
	10	#include <uapi/linux/cifs/cifs_netlink.h>
	11
	12	#include "cifs_swn.h"
	13	#include "cifsglob.h"
	14	#include "cifsproto.h"
	15	#include "fscache.h"
	16	#include "cifs_debug.h"
	17	#include "netlink.h"
	18
	19	static DEFINE_IDR(cifs_swnreg_idr);
	20	static DEFINE_MUTEX(cifs_swnreg_idr_mutex);
	21
	22	struct cifs_swn_reg {
	23	int id;
	24	struct kref ref_count;
	25
	26	const char *net_name;
	27	const char *share_name;
	28	bool net_name_notify;
	29	bool share_name_notify;
	30	bool ip_notify;
	31
	32	struct cifs_tcon *tcon;
	33	};
	34
	35	static int cifs_swn_auth_info_krb(struct cifs_tcon tcon, struct sk_buff skb)
	36	{
	37	int ret;
	38
	39	ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_KRB_AUTH);
	40	if (ret < 0)
	41	return ret;
	42
	43	return 0;
	44	}
	45
	46	static int cifs_swn_auth_info_ntlm(struct cifs_tcon tcon, struct sk_buff skb)
	47	{
	48	int ret;
	49
	50	if (tcon->ses->user_name != NULL) {
	51	ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_USER_NAME, tcon->ses->user_name);
	52	if (ret < 0)
	53	return ret;
	54	}
	55
	56	if (tcon->ses->password != NULL) {
	57	ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_PASSWORD, tcon->ses->password);
	58	if (ret < 0)
	59	return ret;
	60	}
	61
	62	if (tcon->ses->domainName != NULL) {
	63	ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_DOMAIN_NAME, tcon->ses->domainName);
	64	if (ret < 0)
65	return ret;
66	}
67
68	return 0;
69	}
70
71	/*
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
74	* into the message.
75	*/
76	static int cifs_swn_send_register_message(struct cifs_swn_reg *swnreg)
77	{
78	struct sk_buff *skb;
79	struct genlmsghdr *hdr;
80	enum securityEnum authtype;
81	int ret;
82
83	skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
84	if (skb == NULL) {
85	ret = -ENOMEM;
86	goto fail;
87	}
88
89	hdr = genlmsg_put(skb, 0, 0, &cifs_genl_family, 0, CIFS_GENL_CMD_SWN_REGISTER);
90	if (hdr == NULL) {
91	ret = -ENOMEM;
92	goto nlmsg_fail;
93	}
94
95	ret = nla_put_u32(skb, CIFS_GENL_ATTR_SWN_REGISTRATION_ID, swnreg->id);
96	if (ret < 0)
97	goto nlmsg_fail;
98
99	ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_NET_NAME, swnreg->net_name);
100	if (ret < 0)
101	goto nlmsg_fail;
102
103	ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_SHARE_NAME, swnreg->share_name);
104	if (ret < 0)
105	goto nlmsg_fail;
106
107	ret = nla_put(skb, CIFS_GENL_ATTR_SWN_IP, sizeof(struct sockaddr_storage),
108	&swnreg->tcon->ses->server->dstaddr);
109	if (ret < 0)
110	goto nlmsg_fail;
111
112	if (swnreg->net_name_notify) {
113	ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_NET_NAME_NOTIFY);
114	if (ret < 0)
115	goto nlmsg_fail;
116	}
117
118	if (swnreg->share_name_notify) {
119	ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_SHARE_NAME_NOTIFY);
120	if (ret < 0)
121	goto nlmsg_fail;
122	}
123
124	if (swnreg->ip_notify) {
125	ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_IP_NOTIFY);
126	if (ret < 0)
127	goto nlmsg_fail;
128	}
129
130	authtype = cifs_select_sectype(swnreg->tcon->ses->server, swnreg->tcon->ses->sectype);
131	switch (authtype) {
132	case Kerberos:
133	ret = cifs_swn_auth_info_krb(swnreg->tcon, skb);
134	if (ret < 0) {
135	cifs_dbg(VFS, "%s: Failed to get kerberos auth info: %d\n", __func__, ret);
136	goto nlmsg_fail;
137	}
138	break;
139	case LANMAN:
140	case NTLM:
141	case NTLMv2:
142	case RawNTLMSSP:
143	ret = cifs_swn_auth_info_ntlm(swnreg->tcon, skb);
144	if (ret < 0) {
145	cifs_dbg(VFS, "%s: Failed to get NTLM auth info: %d\n", __func__, ret);
146	goto nlmsg_fail;
147	}
148	break;
149	default:
150	cifs_dbg(VFS, "%s: secType %d not supported!\n", __func__, authtype);
151	ret = -EINVAL;
152	goto nlmsg_fail;
153	}
154
155	genlmsg_end(skb, hdr);
156	genlmsg_multicast(&cifs_genl_family, skb, 0, CIFS_GENL_MCGRP_SWN, GFP_ATOMIC);
157
158	cifs_dbg(FYI, "%s: Message to register for network name %s with id %d sent\n", __func__,
159	swnreg->net_name, swnreg->id);
160
161	return 0;
162
163	nlmsg_fail:
164	genlmsg_cancel(skb, hdr);
165	nlmsg_free(skb);
166	fail:
167	return ret;
168	}
169
170	/*
171	* Sends an uregister message to the userspace daemon based on the registration
172	*/
173	static int cifs_swn_send_unregister_message(struct cifs_swn_reg *swnreg)
174	{
175	struct sk_buff *skb;
176	struct genlmsghdr *hdr;
177	int ret;
178
179	skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
180	if (skb == NULL)
181	return -ENOMEM;
182
183	hdr = genlmsg_put(skb, 0, 0, &cifs_genl_family, 0, CIFS_GENL_CMD_SWN_UNREGISTER);
184	if (hdr == NULL) {
185	ret = -ENOMEM;
186	goto nlmsg_fail;
187	}
188
189	ret = nla_put_u32(skb, CIFS_GENL_ATTR_SWN_REGISTRATION_ID, swnreg->id);
190	if (ret < 0)
191	goto nlmsg_fail;
192
193	ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_NET_NAME, swnreg->net_name);
194	if (ret < 0)
195	goto nlmsg_fail;
196
197	ret = nla_put_string(skb, CIFS_GENL_ATTR_SWN_SHARE_NAME, swnreg->share_name);
198	if (ret < 0)
199	goto nlmsg_fail;
200
201	ret = nla_put(skb, CIFS_GENL_ATTR_SWN_IP, sizeof(struct sockaddr_storage),
202	&swnreg->tcon->ses->server->dstaddr);
203	if (ret < 0)
204	goto nlmsg_fail;
205
206	if (swnreg->net_name_notify) {
207	ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_NET_NAME_NOTIFY);
208	if (ret < 0)
209	goto nlmsg_fail;
210	}
211
212	if (swnreg->share_name_notify) {
213	ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_SHARE_NAME_NOTIFY);
214	if (ret < 0)
215	goto nlmsg_fail;
216	}
217
218	if (swnreg->ip_notify) {
219	ret = nla_put_flag(skb, CIFS_GENL_ATTR_SWN_IP_NOTIFY);
220	if (ret < 0)
221	goto nlmsg_fail;
222	}
223
224	genlmsg_end(skb, hdr);
225	genlmsg_multicast(&cifs_genl_family, skb, 0, CIFS_GENL_MCGRP_SWN, GFP_ATOMIC);
226
227	cifs_dbg(FYI, "%s: Message to unregister for network name %s with id %d sent\n", __func__,
228	swnreg->net_name, swnreg->id);
229
230	return 0;
231
232	nlmsg_fail:
233	genlmsg_cancel(skb, hdr);
234	nlmsg_free(skb);
235	return ret;
236	}
237
238	/*
239	* Try to find a matching registration for the tcon's server name and share name.
240	* Calls to this funciton must be protected by cifs_swnreg_idr_mutex.
241	* TODO Try to avoid memory allocations
242	*/
243	static struct cifs_swn_reg cifs_find_swn_reg(struct cifs_tcon tcon)
244	{
245	struct cifs_swn_reg *swnreg;
246	int id;
247	const char *share_name;
248	const char *net_name;
249
250	net_name = extract_hostname(tcon->treeName);
251	if (IS_ERR_OR_NULL(net_name)) {
252	int ret;
253
254	ret = PTR_ERR(net_name);
255	cifs_dbg(VFS, "%s: failed to extract host name from target '%s': %d\n",
256	__func__, tcon->treeName, ret);
257	return NULL;
258	}
259
260	share_name = extract_sharename(tcon->treeName);
261	if (IS_ERR_OR_NULL(share_name)) {
262	int ret;
263
264	ret = PTR_ERR(net_name);
265	cifs_dbg(VFS, "%s: failed to extract share name from target '%s': %d\n",
266	__func__, tcon->treeName, ret);
267	kfree(net_name);
268	return NULL;
269	}
270
271	idr_for_each_entry(&cifs_swnreg_idr, swnreg, id) {
272	if (strcasecmp(swnreg->net_name, net_name) != 0
273	\|\| strcasecmp(swnreg->share_name, share_name) != 0) {
274	continue;
275	}
276
277	mutex_unlock(&cifs_swnreg_idr_mutex);
278
279	cifs_dbg(FYI, "Existing swn registration for %s:%s found\n", swnreg->net_name,
280	swnreg->share_name);
281
282	kfree(net_name);
283	kfree(share_name);
284
285	return swnreg;
286	}
287
288	kfree(net_name);
289	kfree(share_name);
290
291	return NULL;
292	}
293
294	/*
295	* Get a registration for the tcon's server and share name, allocating a new one if it does not
296	* exists
297	*/
298	static struct cifs_swn_reg cifs_get_swn_reg(struct cifs_tcon tcon)
299	{
300	struct cifs_swn_reg *reg = NULL;
301	int ret;
302
303	mutex_lock(&cifs_swnreg_idr_mutex);
304
305	/* Check if we are already registered for this network and share names */
306	reg = cifs_find_swn_reg(tcon);
307	if (IS_ERR(reg)) {
308	return reg;
309	} else if (reg != NULL) {
310	kref_get(&reg->ref_count);
311	mutex_unlock(&cifs_swnreg_idr_mutex);
312	return reg;
313	}
314
315	reg = kmalloc(sizeof(struct cifs_swn_reg), GFP_ATOMIC);
316	if (reg == NULL) {
317	mutex_unlock(&cifs_swnreg_idr_mutex);
318	return ERR_PTR(-ENOMEM);
319	}
320
321	kref_init(&reg->ref_count);
322
323	reg->id = idr_alloc(&cifs_swnreg_idr, reg, 1, 0, GFP_ATOMIC);
324	if (reg->id < 0) {
325	cifs_dbg(FYI, "%s: failed to allocate registration id\n", __func__);
326	ret = reg->id;
327	goto fail;
328	}
329
330	reg->net_name = extract_hostname(tcon->treeName);
331	if (IS_ERR(reg->net_name)) {
332	ret = PTR_ERR(reg->net_name);
333	cifs_dbg(VFS, "%s: failed to extract host name from target: %d\n", __func__, ret);
334	goto fail_idr;
335	}
336
337	reg->share_name = extract_sharename(tcon->treeName);
338	if (IS_ERR(reg->share_name)) {
339	ret = PTR_ERR(reg->share_name);
340	cifs_dbg(VFS, "%s: failed to extract share name from target: %d\n", __func__, ret);
341	goto fail_net_name;
342	}
343
344	reg->net_name_notify = true;
345	reg->share_name_notify = true;
346	reg->ip_notify = (tcon->capabilities & SMB2_SHARE_CAP_SCALEOUT);
347
348	reg->tcon = tcon;
349
350	mutex_unlock(&cifs_swnreg_idr_mutex);
351
352	return reg;
353
354	fail_net_name:
355	kfree(reg->net_name);
356	fail_idr:
357	idr_remove(&cifs_swnreg_idr, reg->id);
358	fail:
359	kfree(reg);
360	mutex_unlock(&cifs_swnreg_idr_mutex);
361	return ERR_PTR(ret);
362	}
363
364	static void cifs_swn_reg_release(struct kref *ref)
365	{
366	struct cifs_swn_reg *swnreg = container_of(ref, struct cifs_swn_reg, ref_count);
367	int ret;
368
369	ret = cifs_swn_send_unregister_message(swnreg);
370	if (ret < 0)
371	cifs_dbg(VFS, "%s: Failed to send unregister message: %d\n", __func__, ret);
372
373	idr_remove(&cifs_swnreg_idr, swnreg->id);
374	kfree(swnreg->net_name);
375	kfree(swnreg->share_name);
376	kfree(swnreg);
377	}
378
379	static void cifs_put_swn_reg(struct cifs_swn_reg *swnreg)
380	{
381	mutex_lock(&cifs_swnreg_idr_mutex);
382	kref_put(&swnreg->ref_count, cifs_swn_reg_release);
383	mutex_unlock(&cifs_swnreg_idr_mutex);
384	}
385
fed979a7 SC	386	static int cifs_swn_resource_state_changed(struct cifs_swn_reg swnreg, const char name, int state)
	387	{
	388	int i;
	389
	390	switch (state) {
	391	case CIFS_SWN_RESOURCE_STATE_UNAVAILABLE:
	392	cifs_dbg(FYI, "%s: resource name '%s' become unavailable\n", __func__, name);
	393	for (i = 0; i < swnreg->tcon->ses->chan_count; i++) {
	394	spin_lock(&GlobalMid_Lock);
	395	if (swnreg->tcon->ses->chans[i].server->tcpStatus != CifsExiting)
	396	swnreg->tcon->ses->chans[i].server->tcpStatus = CifsNeedReconnect;
	397	spin_unlock(&GlobalMid_Lock);
	398	}
	399	break;
	400	case CIFS_SWN_RESOURCE_STATE_AVAILABLE:
	401	cifs_dbg(FYI, "%s: resource name '%s' become available\n", __func__, name);
	402	for (i = 0; i < swnreg->tcon->ses->chan_count; i++) {
	403	spin_lock(&GlobalMid_Lock);
	404	if (swnreg->tcon->ses->chans[i].server->tcpStatus != CifsExiting)
	405	swnreg->tcon->ses->chans[i].server->tcpStatus = CifsNeedReconnect;
	406	spin_unlock(&GlobalMid_Lock);
	407	}
	408	break;
	409	case CIFS_SWN_RESOURCE_STATE_UNKNOWN:
	410	cifs_dbg(FYI, "%s: resource name '%s' changed to unknown state\n", __func__, name);
	411	break;
	412	}
	413	return 0;
	414	}
	415
	416	int cifs_swn_notify(struct sk_buff skb, struct genl_info info)
	417	{
	418	struct cifs_swn_reg *swnreg;
	419	char name[256];
	420	int type;
	421
	422	if (info->attrs[CIFS_GENL_ATTR_SWN_REGISTRATION_ID]) {
	423	int swnreg_id;
	424
	425	swnreg_id = nla_get_u32(info->attrs[CIFS_GENL_ATTR_SWN_REGISTRATION_ID]);
	426	mutex_lock(&cifs_swnreg_idr_mutex);
	427	swnreg = idr_find(&cifs_swnreg_idr, swnreg_id);
	428	mutex_unlock(&cifs_swnreg_idr_mutex);
	429	if (swnreg == NULL) {
	430	cifs_dbg(FYI, "%s: registration id %d not found\n", __func__, swnreg_id);
	431	return -EINVAL;
	432	}
	433	} else {
	434	cifs_dbg(FYI, "%s: missing registration id attribute\n", __func__);
	435	return -EINVAL;
	436	}
	437
	438	if (info->attrs[CIFS_GENL_ATTR_SWN_NOTIFICATION_TYPE]) {
	439	type = nla_get_u32(info->attrs[CIFS_GENL_ATTR_SWN_NOTIFICATION_TYPE]);
	440	} else {
	441	cifs_dbg(FYI, "%s: missing notification type attribute\n", __func__);
	442	return -EINVAL;
	443	}
	444
	445	switch (type) {
	446	case CIFS_SWN_NOTIFICATION_RESOURCE_CHANGE: {
	447	int state;
	448
	449	if (info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_NAME]) {
450	nla_strlcpy(name, info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_NAME],
451	sizeof(name));
452	} else {
453	cifs_dbg(FYI, "%s: missing resource name attribute\n", __func__);
454	return -EINVAL;
455	}
456	if (info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_STATE]) {
457	state = nla_get_u32(info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_STATE]);
458	} else {
459	cifs_dbg(FYI, "%s: missing resource state attribute\n", __func__);
460	return -EINVAL;
461	}
462	return cifs_swn_resource_state_changed(swnreg, name, state);
463	}
464	default:
465	cifs_dbg(FYI, "%s: unknown notification type %d\n", __func__, type);
466	break;
467	}
468
469	return 0;
470	}
471
bf80e5d4 SC	472	int cifs_swn_register(struct cifs_tcon *tcon)
	473	{
	474	struct cifs_swn_reg *swnreg;
	475	int ret;
	476
	477	swnreg = cifs_get_swn_reg(tcon);
	478	if (IS_ERR(swnreg))
	479	return PTR_ERR(swnreg);
	480
	481	ret = cifs_swn_send_register_message(swnreg);
	482	if (ret < 0) {
	483	cifs_dbg(VFS, "%s: Failed to send swn register message: %d\n", __func__, ret);
	484	/* Do not put the swnreg or return error, the echo task will retry */
	485	}
	486
	487	return 0;
	488	}
	489
	490	int cifs_swn_unregister(struct cifs_tcon *tcon)
	491	{
	492	struct cifs_swn_reg *swnreg;
	493
	494	mutex_lock(&cifs_swnreg_idr_mutex);
	495
	496	swnreg = cifs_find_swn_reg(tcon);
	497	if (swnreg == NULL) {
	498	mutex_unlock(&cifs_swnreg_idr_mutex);
	499	return -EEXIST;
	500	}
	501
	502	mutex_unlock(&cifs_swnreg_idr_mutex);
	503
	504	cifs_put_swn_reg(swnreg);
	505
	506	return 0;
	507	}
20fab0da SC	508
	509	void cifs_swn_dump(struct seq_file *m)
	510	{
	511	struct cifs_swn_reg *swnreg;
	512	struct sockaddr_in *sa;
	513	struct sockaddr_in6 *sa6;
	514	int id;
	515
	516	seq_puts(m, "Witness registrations:");
	517
	518	mutex_lock(&cifs_swnreg_idr_mutex);
	519	idr_for_each_entry(&cifs_swnreg_idr, swnreg, id) {
	520	seq_printf(m, "\nId: %u Refs: %u Network name: '%s'%s Share name: '%s'%s Ip address: ",
	521	id, kref_read(&swnreg->ref_count),
	522	swnreg->net_name, swnreg->net_name_notify ? "(y)" : "(n)",
	523	swnreg->share_name, swnreg->share_name_notify ? "(y)" : "(n)");
	524	switch (swnreg->tcon->ses->server->dstaddr.ss_family) {
	525	case AF_INET:
	526	sa = (struct sockaddr_in *) &swnreg->tcon->ses->server->dstaddr;
	527	seq_printf(m, "%pI4", &sa->sin_addr.s_addr);
	528	break;
	529	case AF_INET6:
	530	sa6 = (struct sockaddr_in6 *) &swnreg->tcon->ses->server->dstaddr;
	531	seq_printf(m, "%pI6", &sa6->sin6_addr.s6_addr);
	532	if (sa6->sin6_scope_id)
	533	seq_printf(m, "%%%u", sa6->sin6_scope_id);
	534	break;
	535	default:
	536	seq_puts(m, "(unknown)");
	537	}
	538	seq_printf(m, "%s", swnreg->ip_notify ? "(y)" : "(n)");
	539	}
	540	mutex_unlock(&cifs_swnreg_idr_mutex);
	541	seq_puts(m, "\n");
	542	}
21077c62 SC	543
	544	void cifs_swn_check(void)
	545	{
	546	struct cifs_swn_reg *swnreg;
	547	int id;
	548	int ret;
	549
	550	mutex_lock(&cifs_swnreg_idr_mutex);
	551	idr_for_each_entry(&cifs_swnreg_idr, swnreg, id) {
	552	ret = cifs_swn_send_register_message(swnreg);
	553	if (ret < 0)
	554	cifs_dbg(FYI, "%s: Failed to send register message: %d\n", __func__, ret);
	555	}
	556	mutex_unlock(&cifs_swnreg_idr_mutex);
	557	}