[GitHub/LineageOS/android_kernel_motorola_exynos9610.git] / tools / hv / hv_vss_daemon.c

/*
 * An implementation of the host initiated guest snapshot for Hyper-V.
 *
 *
 * Copyright (C) 2013, Microsoft, Inc.
 * Author : K. Y. Srinivasan <kys@microsoft.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 * NON INFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 */


#include <sys/types.h>
#include <sys/socket.h>
#include <sys/poll.h>
#include <linux/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <arpa/inet.h>
#include <linux/connector.h>
#include <linux/hyperv.h>
#include <linux/netlink.h>
#include <syslog.h>

static char vss_recv_buffer[4096];
static char vss_send_buffer[4096];
static struct sockaddr_nl addr;

#ifndef SOL_NETLINK
#define SOL_NETLINK 270
#endif


static int vss_operate(int operation)
{
	char *fs_op;
	char cmd[512];
	char buf[512];
	FILE *file;
	char *p;
	char *x;
	int error;

	switch (operation) {
	case VSS_OP_FREEZE:
		fs_op = "-f ";
		break;
	case VSS_OP_THAW:
		fs_op = "-u ";
		break;
	}

	file = popen("mount | awk '/^\/dev\// { print $3}'", "r");
	if (file == NULL)
		return;

	while ((p = fgets(buf, sizeof(buf), file)) != NULL) {
		x = strchr(p, '\n');
		*x = '\0';
		if (!strncmp(p, "/", sizeof("/")))
			continue;

		sprintf(cmd, "%s %s %s", "fsfreeze ", fs_op, p);
		syslog(LOG_INFO, "VSS cmd is %s\n", cmd);
		error = system(cmd);
	}
	pclose(file);

	sprintf(cmd, "%s %s %s", "fsfreeze ", fs_op, "/");
	syslog(LOG_INFO, "VSS cmd is %s\n", cmd);
	error = system(cmd);

	return error;
}

static int netlink_send(int fd, struct cn_msg *msg)
{
	struct nlmsghdr *nlh;
	unsigned int size;
	struct msghdr message;
	char buffer[64];
	struct iovec iov[2];

	size = NLMSG_SPACE(sizeof(struct cn_msg) + msg->len);

	nlh = (struct nlmsghdr *)buffer;
	nlh->nlmsg_seq = 0;
	nlh->nlmsg_pid = getpid();
	nlh->nlmsg_type = NLMSG_DONE;
	nlh->nlmsg_len = NLMSG_LENGTH(size - sizeof(*nlh));
	nlh->nlmsg_flags = 0;

	iov[0].iov_base = nlh;
	iov[0].iov_len = sizeof(*nlh);

	iov[1].iov_base = msg;
	iov[1].iov_len = size;

	memset(&message, 0, sizeof(message));
	message.msg_name = &addr;
	message.msg_namelen = sizeof(addr);
	message.msg_iov = iov;
	message.msg_iovlen = 2;

	return sendmsg(fd, &message, 0);
}

int main(void)
{
	int fd, len, nl_group;
	int error;
	struct cn_msg *message;
	struct pollfd pfd;
	struct nlmsghdr *incoming_msg;
	struct cn_msg	*incoming_cn_msg;
	int	op;
	struct hv_vss_msg *vss_msg;

	daemon(1, 0);
	openlog("Hyper-V VSS", 0, LOG_USER);
	syslog(LOG_INFO, "VSS starting; pid is:%d", getpid());

	fd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_CONNECTOR);
	if (fd < 0) {
		syslog(LOG_ERR, "netlink socket creation failed; error:%d", fd);
		exit(EXIT_FAILURE);
	}
	addr.nl_family = AF_NETLINK;
	addr.nl_pad = 0;
	addr.nl_pid = 0;
	addr.nl_groups = 0;


	error = bind(fd, (struct sockaddr *)&addr, sizeof(addr));
	if (error < 0) {
		syslog(LOG_ERR, "bind failed; error:%d", error);
		close(fd);
		exit(EXIT_FAILURE);
	}
	nl_group = CN_VSS_IDX;
	setsockopt(fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &nl_group, sizeof(nl_group));
	/*
	 * Register ourselves with the kernel.
	 */
	message = (struct cn_msg *)vss_send_buffer;
	message->id.idx = CN_VSS_IDX;
	message->id.val = CN_VSS_VAL;
	message->ack = 0;
	vss_msg = (struct hv_vss_msg *)message->data;
	vss_msg->vss_hdr.operation = VSS_OP_REGISTER;

	message->len = sizeof(struct hv_vss_msg);

	len = netlink_send(fd, message);
	if (len < 0) {
		syslog(LOG_ERR, "netlink_send failed; error:%d", len);
		close(fd);
		exit(EXIT_FAILURE);
	}

	pfd.fd = fd;

	while (1) {
		struct sockaddr *addr_p = (struct sockaddr *) &addr;
		socklen_t addr_l = sizeof(addr);
		pfd.events = POLLIN;
		pfd.revents = 0;
		poll(&pfd, 1, -1);

		len = recvfrom(fd, vss_recv_buffer, sizeof(vss_recv_buffer), 0,
				addr_p, &addr_l);

		if (len < 0 || addr.nl_pid) {
			syslog(LOG_ERR, "recvfrom failed; pid:%u error:%d %s",
					addr.nl_pid, errno, strerror(errno));
			close(fd);
			return -1;
		}

		incoming_msg = (struct nlmsghdr *)vss_recv_buffer;

		if (incoming_msg->nlmsg_type != NLMSG_DONE)
			continue;

		incoming_cn_msg = (struct cn_msg *)NLMSG_DATA(incoming_msg);
		vss_msg = (struct hv_vss_msg *)incoming_cn_msg->data;
		op = vss_msg->vss_hdr.operation;
		error =  HV_S_OK;

		switch (op) {
		case VSS_OP_FREEZE:
		case VSS_OP_THAW:
			error = vss_operate(op);
			if (error)
				error = HV_E_FAIL;
			break;
		default:
			syslog(LOG_ERR, "Illegal op:%d\n", op);
		}
		vss_msg->error = error;
		len = netlink_send(fd, incoming_cn_msg);
		if (len < 0) {
			syslog(LOG_ERR, "net_link send failed; error:%d", len);
			exit(EXIT_FAILURE);
		}
	}

}
Commit	Line	Data
96dd86fa S	1	/*
	2	* An implementation of the host initiated guest snapshot for Hyper-V.
	3	*
	4	*
	5	* Copyright (C) 2013, Microsoft, Inc.
	6	* Author : K. Y. Srinivasan <kys@microsoft.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	*/
	19
	20
	21	#include <sys/types.h>
	22	#include <sys/socket.h>
	23	#include <sys/poll.h>
	24	#include <linux/types.h>
	25	#include <stdio.h>
	26	#include <stdlib.h>
	27	#include <unistd.h>
	28	#include <string.h>
	29	#include <ctype.h>
	30	#include <errno.h>
	31	#include <arpa/inet.h>
	32	#include <linux/connector.h>
	33	#include <linux/hyperv.h>
	34	#include <linux/netlink.h>
	35	#include <syslog.h>
	36
	37	static char vss_recv_buffer[4096];
	38	static char vss_send_buffer[4096];
	39	static struct sockaddr_nl addr;
	40
	41	#ifndef SOL_NETLINK
	42	#define SOL_NETLINK 270
	43	#endif
	44
	45
	46	static int vss_operate(int operation)
	47	{
	48	char *fs_op;
	49	char cmd[512];
	50	char buf[512];
	51	FILE *file;
	52	char *p;
	53	char *x;
	54	int error;
	55
	56	switch (operation) {
	57	case VSS_OP_FREEZE:
	58	fs_op = "-f ";
	59	break;
	60	case VSS_OP_THAW:
	61	fs_op = "-u ";
	62	break;
	63	}
	64
65	file = popen("mount \| awk '/^\/dev\// { print $3}'", "r");
66	if (file == NULL)
67	return;
68
69	while ((p = fgets(buf, sizeof(buf), file)) != NULL) {
70	x = strchr(p, '\n');
71	*x = '\0';
72	if (!strncmp(p, "/", sizeof("/")))
73	continue;
74
75	sprintf(cmd, "%s %s %s", "fsfreeze ", fs_op, p);
76	syslog(LOG_INFO, "VSS cmd is %s\n", cmd);
77	error = system(cmd);
78	}
79	pclose(file);
80
81	sprintf(cmd, "%s %s %s", "fsfreeze ", fs_op, "/");
82	syslog(LOG_INFO, "VSS cmd is %s\n", cmd);
83	error = system(cmd);
84
85	return error;
86	}
87
88	static int netlink_send(int fd, struct cn_msg *msg)
89	{
90	struct nlmsghdr *nlh;
91	unsigned int size;
92	struct msghdr message;
93	char buffer[64];
94	struct iovec iov[2];
95
96	size = NLMSG_SPACE(sizeof(struct cn_msg) + msg->len);
97
98	nlh = (struct nlmsghdr *)buffer;
99	nlh->nlmsg_seq = 0;
100	nlh->nlmsg_pid = getpid();
101	nlh->nlmsg_type = NLMSG_DONE;
102	nlh->nlmsg_len = NLMSG_LENGTH(size - sizeof(*nlh));
103	nlh->nlmsg_flags = 0;
104
105	iov[0].iov_base = nlh;
106	iov[0].iov_len = sizeof(*nlh);
107
108	iov[1].iov_base = msg;
109	iov[1].iov_len = size;
110
111	memset(&message, 0, sizeof(message));
112	message.msg_name = &addr;
113	message.msg_namelen = sizeof(addr);
114	message.msg_iov = iov;
115	message.msg_iovlen = 2;
116
117	return sendmsg(fd, &message, 0);
118	}
119
120	int main(void)
121	{
122	int fd, len, nl_group;
123	int error;
124	struct cn_msg *message;
125	struct pollfd pfd;
126	struct nlmsghdr *incoming_msg;
127	struct cn_msg *incoming_cn_msg;
128	int op;
129	struct hv_vss_msg *vss_msg;
130
131	daemon(1, 0);
132	openlog("Hyper-V VSS", 0, LOG_USER);
133	syslog(LOG_INFO, "VSS starting; pid is:%d", getpid());
134
135	fd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_CONNECTOR);
136	if (fd < 0) {
137	syslog(LOG_ERR, "netlink socket creation failed; error:%d", fd);
138	exit(EXIT_FAILURE);
139	}
140	addr.nl_family = AF_NETLINK;
141	addr.nl_pad = 0;
142	addr.nl_pid = 0;
143	addr.nl_groups = 0;
144
145
146	error = bind(fd, (struct sockaddr *)&addr, sizeof(addr));
147	if (error < 0) {
148	syslog(LOG_ERR, "bind failed; error:%d", error);
149	close(fd);
150	exit(EXIT_FAILURE);
151	}
152	nl_group = CN_VSS_IDX;
153	setsockopt(fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &nl_group, sizeof(nl_group));
154	/*
155	* Register ourselves with the kernel.
156	*/
157	message = (struct cn_msg *)vss_send_buffer;
158	message->id.idx = CN_VSS_IDX;
159	message->id.val = CN_VSS_VAL;
160	message->ack = 0;
161	vss_msg = (struct hv_vss_msg *)message->data;
162	vss_msg->vss_hdr.operation = VSS_OP_REGISTER;
163
164	message->len = sizeof(struct hv_vss_msg);
165
166	len = netlink_send(fd, message);
167	if (len < 0) {
168	syslog(LOG_ERR, "netlink_send failed; error:%d", len);
169	close(fd);
170	exit(EXIT_FAILURE);
171	}
172
173	pfd.fd = fd;
174
175	while (1) {
176	struct sockaddr addr_p = (struct sockaddr ) &addr;
177	socklen_t addr_l = sizeof(addr);
178	pfd.events = POLLIN;
179	pfd.revents = 0;
180	poll(&pfd, 1, -1);
181
182	len = recvfrom(fd, vss_recv_buffer, sizeof(vss_recv_buffer), 0,
183	addr_p, &addr_l);
184
185	if (len < 0 \|\| addr.nl_pid) {
186	syslog(LOG_ERR, "recvfrom failed; pid:%u error:%d %s",
187	addr.nl_pid, errno, strerror(errno));
188	close(fd);
189	return -1;
190	}
191
192	incoming_msg = (struct nlmsghdr *)vss_recv_buffer;
193
194	if (incoming_msg->nlmsg_type != NLMSG_DONE)
195	continue;
196
197	incoming_cn_msg = (struct cn_msg *)NLMSG_DATA(incoming_msg);
198	vss_msg = (struct hv_vss_msg *)incoming_cn_msg->data;
199	op = vss_msg->vss_hdr.operation;
200	error = HV_S_OK;
201
202	switch (op) {
203	case VSS_OP_FREEZE:
204	case VSS_OP_THAW:
205	error = vss_operate(op);
206	if (error)
207	error = HV_E_FAIL;
208	break;
209	default:
210	syslog(LOG_ERR, "Illegal op:%d\n", op);
211	}
212	vss_msg->error = error;
213	len = netlink_send(fd, incoming_cn_msg);
214	if (len < 0) {
215	syslog(LOG_ERR, "net_link send failed; error:%d", len);
216	exit(EXIT_FAILURE);
217	}
218	}
219
220	}