[deliverable/linux.git] / tools / hv / hv_fcopy_daemon.c

/*
 * An implementation of host to guest copy functionality for Linux.
 *
 * Copyright (C) 2014, 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 <linux/kdev_t.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <linux/hyperv.h>
#include <syslog.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <dirent.h>
#include <getopt.h>

static int target_fd;
static char target_fname[W_MAX_PATH];

static int hv_start_fcopy(struct hv_start_fcopy *smsg)
{
	int error = HV_E_FAIL;
	char *q, *p;

	p = (char *)smsg->path_name;
	snprintf(target_fname, sizeof(target_fname), "%s/%s",
		 (char *)smsg->path_name, (char *)smsg->file_name);

	syslog(LOG_INFO, "Target file name: %s", target_fname);
	/*
	 * Check to see if the path is already in place; if not,
	 * create if required.
	 */
	while ((q = strchr(p, '/')) != NULL) {
		if (q == p) {
			p++;
			continue;
		}
		*q = '\0';
		if (access((char *)smsg->path_name, F_OK)) {
			if (smsg->copy_flags & CREATE_PATH) {
				if (mkdir((char *)smsg->path_name, 0755)) {
					syslog(LOG_ERR, "Failed to create %s",
						(char *)smsg->path_name);
					goto done;
				}
			} else {
				syslog(LOG_ERR, "Invalid path: %s",
					(char *)smsg->path_name);
				goto done;
			}
		}
		p = q + 1;
		*q = '/';
	}

	if (!access(target_fname, F_OK)) {
		syslog(LOG_INFO, "File: %s exists", target_fname);
		if (!(smsg->copy_flags & OVER_WRITE)) {
			error = HV_ERROR_ALREADY_EXISTS;
			goto done;
		}
	}

	target_fd = open(target_fname,
			 O_RDWR | O_CREAT | O_TRUNC | O_CLOEXEC, 0744);
	if (target_fd == -1) {
		syslog(LOG_INFO, "Open Failed: %s", strerror(errno));
		goto done;
	}

	error = 0;
done:
	return error;
}

static int hv_copy_data(struct hv_do_fcopy *cpmsg)
{
	ssize_t bytes_written;

	bytes_written = pwrite(target_fd, cpmsg->data, cpmsg->size,
				cpmsg->offset);

	if (bytes_written != cpmsg->size)
		return HV_E_FAIL;

	return 0;
}

static int hv_copy_finished(void)
{
	close(target_fd);
	return 0;
}
static int hv_copy_cancel(void)
{
	close(target_fd);
	unlink(target_fname);
	return 0;

}

void print_usage(char *argv[])
{
	fprintf(stderr, "Usage: %s [options]\n"
		"Options are:\n"
		"  -n, --no-daemon        stay in foreground, don't daemonize\n"
		"  -h, --help             print this help\n", argv[0]);
}

int main(int argc, char *argv[])
{
	int fcopy_fd, len;
	int error;
	int daemonize = 1, long_index = 0, opt;
	int version = FCOPY_CURRENT_VERSION;
	char *buffer[4096 * 2];
	struct hv_fcopy_hdr *in_msg;
	int in_handshake = 1;
	__u32 kernel_modver;

	static struct option long_options[] = {
		{"help",	no_argument,	   0,  'h' },
		{"no-daemon",	no_argument,	   0,  'n' },
		{0,		0,		   0,  0   }
	};

	while ((opt = getopt_long(argc, argv, "hn", long_options,
				  &long_index)) != -1) {
		switch (opt) {
		case 'n':
			daemonize = 0;
			break;
		case 'h':
		default:
			print_usage(argv);
			exit(EXIT_FAILURE);
		}
	}

	if (daemonize && daemon(1, 0)) {
		syslog(LOG_ERR, "daemon() failed; error: %s", strerror(errno));
		exit(EXIT_FAILURE);
	}

	openlog("HV_FCOPY", 0, LOG_USER);
	syslog(LOG_INFO, "HV_FCOPY starting; pid is:%d", getpid());

	fcopy_fd = open("/dev/vmbus/hv_fcopy", O_RDWR);

	if (fcopy_fd < 0) {
		syslog(LOG_ERR, "open /dev/vmbus/hv_fcopy failed; error: %d %s",
			errno, strerror(errno));
		exit(EXIT_FAILURE);
	}

	/*
	 * Register with the kernel.
	 */
	if ((write(fcopy_fd, &version, sizeof(int))) != sizeof(int)) {
		syslog(LOG_ERR, "Registration failed: %s", strerror(errno));
		exit(EXIT_FAILURE);
	}

	while (1) {
		/*
		 * In this loop we process fcopy messages after the
		 * handshake is complete.
		 */
		len = pread(fcopy_fd, buffer, (4096 * 2), 0);
		if (len < 0) {
			syslog(LOG_ERR, "pread failed: %s", strerror(errno));
			exit(EXIT_FAILURE);
		}

		if (in_handshake) {
			if (len != sizeof(kernel_modver)) {
				syslog(LOG_ERR, "invalid version negotiation");
				exit(EXIT_FAILURE);
			}
			kernel_modver = *(__u32 *)buffer;
			in_handshake = 0;
			syslog(LOG_INFO, "HV_FCOPY: kernel module version: %d",
			       kernel_modver);
			continue;
		}

		in_msg = (struct hv_fcopy_hdr *)buffer;

		switch (in_msg->operation) {
		case START_FILE_COPY:
			error = hv_start_fcopy((struct hv_start_fcopy *)in_msg);
			break;
		case WRITE_TO_FILE:
			error = hv_copy_data((struct hv_do_fcopy *)in_msg);
			break;
		case COMPLETE_FCOPY:
			error = hv_copy_finished();
			break;
		case CANCEL_FCOPY:
			error = hv_copy_cancel();
			break;

		default:
			syslog(LOG_ERR, "Unknown operation: %d",
				in_msg->operation);

		}

		if (pwrite(fcopy_fd, &error, sizeof(int), 0) != sizeof(int)) {
			syslog(LOG_ERR, "pwrite failed: %s", strerror(errno));
			exit(EXIT_FAILURE);
		}
	}
}
Commit	Line	Data
01325476 S	1	/*
	2	* An implementation of host to guest copy functionality for Linux.
	3	*
	4	* Copyright (C) 2014, Microsoft, Inc.
	5	*
	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	#include <sys/types.h>
	21	#include <sys/socket.h>
	22	#include <sys/poll.h>
	23	#include <linux/types.h>
	24	#include <linux/kdev_t.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 <linux/hyperv.h>
	32	#include <syslog.h>
	33	#include <sys/stat.h>
	34	#include <fcntl.h>
	35	#include <dirent.h>
170f4bea	36	#include <getopt.h>
01325476 S	37
	38	static int target_fd;
	39	static char target_fname[W_MAX_PATH];
	40
	41	static int hv_start_fcopy(struct hv_start_fcopy *smsg)
	42	{
	43	int error = HV_E_FAIL;
	44	char q, p;
	45
01325476 S	46	p = (char *)smsg->path_name;
01325476 S	47	snprintf(target_fname, sizeof(target_fname), "%s/%s",
aba474b8	48	(char )smsg->path_name, (char )smsg->file_name);
01325476 S	49
	50	syslog(LOG_INFO, "Target file name: %s", target_fname);
	51	/*
	52	* Check to see if the path is already in place; if not,
	53	* create if required.
	54	*/
	55	while ((q = strchr(p, '/')) != NULL) {
	56	if (q == p) {
	57	p++;
	58	continue;
	59	}
	60	*q = '\0';
	61	if (access((char *)smsg->path_name, F_OK)) {
	62	if (smsg->copy_flags & CREATE_PATH) {
	63	if (mkdir((char *)smsg->path_name, 0755)) {
	64	syslog(LOG_ERR, "Failed to create %s",
	65	(char *)smsg->path_name);
	66	goto done;
	67	}
	68	} else {
	69	syslog(LOG_ERR, "Invalid path: %s",
	70	(char *)smsg->path_name);
	71	goto done;
	72	}
	73	}
	74	p = q + 1;
	75	*q = '/';
	76	}
	77
	78	if (!access(target_fname, F_OK)) {
	79	syslog(LOG_INFO, "File: %s exists", target_fname);
314672a2 S	80	if (!(smsg->copy_flags & OVER_WRITE)) {
314672a2 S	81	error = HV_ERROR_ALREADY_EXISTS;
01325476	82	goto done;
314672a2	83	}
01325476 S	84	}
01325476 S	85
e013ac31 YZ	86	target_fd = open(target_fname,
e013ac31 YZ	87	O_RDWR \| O_CREAT \| O_TRUNC \| O_CLOEXEC, 0744);
01325476 S	88	if (target_fd == -1) {
	89	syslog(LOG_INFO, "Open Failed: %s", strerror(errno));
	90	goto done;
	91	}
	92
	93	error = 0;
	94	done:
	95	return error;
	96	}
	97
	98	static int hv_copy_data(struct hv_do_fcopy *cpmsg)
	99	{
	100	ssize_t bytes_written;
	101
	102	bytes_written = pwrite(target_fd, cpmsg->data, cpmsg->size,
	103	cpmsg->offset);
	104
	105	if (bytes_written != cpmsg->size)
	106	return HV_E_FAIL;
	107
	108	return 0;
	109	}
	110
	111	static int hv_copy_finished(void)
	112	{
	113	close(target_fd);
	114	return 0;
	115	}
	116	static int hv_copy_cancel(void)
	117	{
	118	close(target_fd);
	119	unlink(target_fname);
	120	return 0;
	121
	122	}
	123
170f4bea VK	124	void print_usage(char *argv[])
	125	{
	126	fprintf(stderr, "Usage: %s [options]\n"
	127	"Options are:\n"
	128	" -n, --no-daemon stay in foreground, don't daemonize\n"
	129	" -h, --help print this help\n", argv[0]);
	130	}
	131
	132	int main(int argc, char *argv[])
01325476	133	{
aba474b8	134	int fcopy_fd, len;
01325476	135	int error;
170f4bea	136	int daemonize = 1, long_index = 0, opt;
01325476 S	137	int version = FCOPY_CURRENT_VERSION;
	138	char buffer[4096 2];
	139	struct hv_fcopy_hdr *in_msg;
a4d1ee5b VK	140	int in_handshake = 1;
a4d1ee5b VK	141	__u32 kernel_modver;
01325476	142
170f4bea VK	143	static struct option long_options[] = {
	144	{"help", no_argument, 0, 'h' },
	145	{"no-daemon", no_argument, 0, 'n' },
	146	{0, 0, 0, 0 }
	147	};
	148
	149	while ((opt = getopt_long(argc, argv, "hn", long_options,
	150	&long_index)) != -1) {
	151	switch (opt) {
	152	case 'n':
	153	daemonize = 0;
	154	break;
	155	case 'h':
	156	default:
	157	print_usage(argv);
	158	exit(EXIT_FAILURE);
	159	}
	160	}
	161
	162	if (daemonize && daemon(1, 0)) {
01325476 S	163	syslog(LOG_ERR, "daemon() failed; error: %s", strerror(errno));
	164	exit(EXIT_FAILURE);
	165	}
	166
	167	openlog("HV_FCOPY", 0, LOG_USER);
	168	syslog(LOG_INFO, "HV_FCOPY starting; pid is:%d", getpid());
	169
	170	fcopy_fd = open("/dev/vmbus/hv_fcopy", O_RDWR);
	171
	172	if (fcopy_fd < 0) {
	173	syslog(LOG_ERR, "open /dev/vmbus/hv_fcopy failed; error: %d %s",
	174	errno, strerror(errno));
	175	exit(EXIT_FAILURE);
	176	}
	177
	178	/*
	179	* Register with the kernel.
	180	*/
	181	if ((write(fcopy_fd, &version, sizeof(int))) != sizeof(int)) {
	182	syslog(LOG_ERR, "Registration failed: %s", strerror(errno));
	183	exit(EXIT_FAILURE);
	184	}
	185
	186	while (1) {
	187	/*
	188	* In this loop we process fcopy messages after the
	189	* handshake is complete.
	190	*/
	191	len = pread(fcopy_fd, buffer, (4096 * 2), 0);
	192	if (len < 0) {
	193	syslog(LOG_ERR, "pread failed: %s", strerror(errno));
	194	exit(EXIT_FAILURE);
	195	}
a4d1ee5b VK	196
	197	if (in_handshake) {
	198	if (len != sizeof(kernel_modver)) {
	199	syslog(LOG_ERR, "invalid version negotiation");
	200	exit(EXIT_FAILURE);
	201	}
	202	kernel_modver = (__u32 )buffer;
	203	in_handshake = 0;
	204	syslog(LOG_INFO, "HV_FCOPY: kernel module version: %d",
	205	kernel_modver);
	206	continue;
	207	}
	208
01325476 S	209	in_msg = (struct hv_fcopy_hdr *)buffer;
	210
	211	switch (in_msg->operation) {
	212	case START_FILE_COPY:
	213	error = hv_start_fcopy((struct hv_start_fcopy *)in_msg);
	214	break;
	215	case WRITE_TO_FILE:
	216	error = hv_copy_data((struct hv_do_fcopy *)in_msg);
	217	break;
	218	case COMPLETE_FCOPY:
	219	error = hv_copy_finished();
	220	break;
	221	case CANCEL_FCOPY:
	222	error = hv_copy_cancel();
	223	break;
	224
	225	default:
	226	syslog(LOG_ERR, "Unknown operation: %d",
	227	in_msg->operation);
	228
	229	}
	230
	231	if (pwrite(fcopy_fd, &error, sizeof(int), 0) != sizeof(int)) {
	232	syslog(LOG_ERR, "pwrite failed: %s", strerror(errno));
	233	exit(EXIT_FAILURE);
	234	}
	235	}
	236	}