[mirror_ubuntu-artful-kernel.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;

	/*
	 * If possile append a path seperator to the path.
	 */
	if (strlen((char *)smsg->path_name) < (W_MAX_PATH - 2))
		strcat((char *)smsg->path_name, "/");

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

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