iscsi_config.c

iscsi源代码 UNH的progect 有initiator端和target端的源码

/*	initiator/iscsi_config.c

	vi: set autoindent tabstop=4 shiftwidth=4 :

	This file contains the core functions to initiate session to the target.
	The file when compiled generates a user-level program which calls
	iscsi_initiator.c functions through /proc filesystem interface.

*/
/*
	Copyright (C) 2001-2003 InterOperability Lab (IOL)
	University of New Hampshier (UNH)
	Durham, NH 03824

	This program is free software; you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation; either version 2, or (at your option)
	any later version.

	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.  See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to the Free Software
	Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
	USA.

	The name of IOL and/or UNH may not be used to endorse or promote products
	derived from this software without specific prior written permission.
*/

#define	_POSIX_C_SOURCE	199506L

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <ctype.h>
#include <string.h>
#include <errno.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <asm/param.h>
#include <asm/types.h>
#include <sys/param.h>
#include <scsi/scsi.h>
#include <sys/stat.h>

#include "iscsi_common.h"
#include "debug.h"

extern int ioctl(int, int, ...);

#define DEFAULT_HOST_NO		0
#define DEFAULT_TARGET_NO	0
#define DEFAULT_LUN_NO		-1
#define DEFAULT_CID_NO		0
#define WHITE_SPACE	" \t\v\f\n\r"

#define UNH_ISCSI_DEV_DIR	"/opt/unh/iscsi/dev"
#define MAX_LUNS			8

char server_node[MAXHOSTNAMELEN];
char target_dir[MAXPATHLEN];
char target_node[MAXPATHLEN];
char cmd[MAXPATHLEN];

int
create_device_nodes(char *target_dir, int host_no, int target_no, int lun_no)
{
	char disk_fmt[] = "/dev/sd%c";
	char tape_fmt[] = "/dev/st%d";
	char cd_fmt[] = "/dev/scd%d";
	char disk_name[10], disk_part[10];
	char tape_name[10], tape_subname[10];
	char cd_name[10];
	char tape_types[] = { 'a', 'l', 'm', 0 };
	int fd, ret = 0, id_buf[2], found = 0;
	int host, chan, lun, id, i = 0, p = 0;

	/* First do the disks */
	for (i = 'a'; i <= 'z'; i++) {
		sprintf(disk_name, disk_fmt, i);

		fd = open(disk_name, O_RDONLY);
		if (fd <= 0)
			continue;

		ret = ioctl(fd, SCSI_IOCTL_GET_IDLUN, &id_buf);
		close(fd);
		if (ret) {
			continue;
		}

		TRACE(TRACE_DEBUG,
			  "create_device_nodes disk_name: %s, id_buf: 0x%08x\n",
			  disk_name, id_buf[0]);

		host = (id_buf[0] >> 24) & 0xff;
		chan = (id_buf[0] >> 16) & 0xff;
		lun = (id_buf[0] >> 8) & 0xff;
		id = (id_buf[0] & 0xff);

		if (host != host_no || chan != 0 ||
				id != target_no || lun != lun_no) {
			continue;
		}

		found++;

		TRACE(TRACE_DEBUG,
			  "create_device_nodes found %d, target_dir: %s, "
			  "lun_no %d\n", found, target_dir, lun_no);

		sprintf(target_node, "%s/l%d", target_dir, lun_no);
		ret = link(disk_name, target_node);
		if (ret) {
			printf("Unable to link %s to %s \n", target_node,
				disk_name);
			goto out;
		}

		TRACE(TRACE_DEBUG, "Able to link %s to %s \n", target_node,
			disk_name);

		for (p = 1; p <= 15; p++) {
			sprintf(target_node, "%s/l%dp%d", target_dir,
				lun_no, p);
			sprintf(disk_part, "%s%d", disk_name, p);
			ret = link(disk_part, target_node);
			if (ret) {
				printf("Unable to link %s to %s \n",
					target_node, disk_part);
				goto out;
			}
		}
	}

	if (found)
		goto out;

	/* Check for SCSI tapes */
	for (i = 0; i <= 9; i++) {
		sprintf(tape_name, tape_fmt, i);

		fd = open(tape_name, O_RDONLY);
		if (fd <= 0)
			continue;

		ret = ioctl(fd, SCSI_IOCTL_GET_IDLUN, &id_buf);
		close(fd);
		if (ret) {
			continue;
		}

		TRACE(TRACE_DEBUG,
			  "create_device_nodes tape_name: %s, id_buf: 0x%08x\n",
			  tape_name, id_buf[0]);

		host = (id_buf[0] >> 24) & 0xff;
		chan = (id_buf[0] >> 16) & 0xff;
		lun = (id_buf[0] >> 8) & 0xff;
		id = (id_buf[0] & 0xff);

		if (host != host_no || chan != 0 || id != target_no ||
			lun != lun_no) {
			continue;
		}

		found++;

		TRACE(TRACE_DEBUG,
			  "create_device_nodes found %d, target_dir: %s, "
			  "lun_no %d\n", found, target_dir, lun_no);

		sprintf(target_node, "%s/l%d", target_dir, lun_no);
		ret = link(tape_name, target_node);
		if (ret) {
			printf("Unable to link %s to %s \n",
				target_node, tape_name);
			goto out;
		}

		TRACE(TRACE_DEBUG, "Able to link %s to %s \n", target_node,
			tape_name);

		for (p = 0; tape_types[p]; p++) {
			TRACE(TRACE_DEBUG, "p: %d, tape_types[p]: %c\n", p,
				tape_types[p]);
			sprintf(tape_subname, "%s%c", tape_name, tape_types[p]);
			sprintf(target_node, "%s/l%d%c", target_dir,
				lun_no, tape_types[p]);
			ret = link(tape_subname, target_node);
			if (ret) {
				printf("Unable to link %s to %s \n",
					target_node, tape_subname);
				goto out;
			}
			TRACE(TRACE_DEBUG, "Able to link %s to %s \n",
				  target_node, tape_subname);
		}
	}

	if (found)
		goto out;

	/* Check for SCSI CD-ROMs */
	for (i = 0; i <= 9; i++) {
		sprintf(cd_name, cd_fmt, i);

		fd = open(cd_name, O_RDONLY);
		if (fd <= 0)
			continue;

		ret = ioctl(fd, SCSI_IOCTL_GET_IDLUN, &id_buf);
		close(fd);
		if (ret) {
			continue;
		}

		TRACE(TRACE_DEBUG,
			  "create_device_nodes cd_name: %s, id_buf: 0x%08x\n",
			  cd_name, id_buf[0]);

		host = (id_buf[0] >> 24) & 0xff;
		chan = (id_buf[0] >> 16) & 0xff;
		lun = (id_buf[0] >> 8) & 0xff;
		id = (id_buf[0] & 0xff);

		if (host != host_no || chan != 0 || id != target_no ||
				lun != lun_no) {
			continue;
		}

		found++;

		TRACE(TRACE_DEBUG,
			  "create_device_nodes found %d, target_dir: %s, "
			  "lun_no %d\n", found, target_dir, lun_no);

		sprintf(target_node, "%s/l%d", target_dir, lun_no);
		ret = link(cd_name, target_node);
		if (ret) {
			printf("Unable to link %s to %s \n", target_node,
				cd_name);
			goto out;
		}
	}

  out:
	TRACE(TRACE_DEBUG, "create_device_nodes exiting\n");

	return (ret);
}

/*	creates the directory given by path, including all
 * 	directories in path
 *	path must be an absolute path name
 *	returns 0 on success, -1 on error
 */
int
make_full_path_dir(char *path)
{
	char *ptr, *partial_path = NULL;
	int len, mode;
	int retval = -1;			/* assume this function fails */

	if (path == NULL || (len = strlen(path)) <= 0) {
		/* path is bogus */
		goto early_out;
	}

	if (*path != '/') {
		/* path is relative, not absolute */
		goto early_out;
	}
	/* else path is absolute */

	if ((ptr = partial_path = malloc(len + 1)) == NULL)
		goto early_out;

	/* we need a copy of path because we are going to mess it up */
	strcpy(partial_path, path);

	mode = X_OK;	/* only need x access to intermediate directories */
	if (len == 1) {
		mode |= R_OK | W_OK;	/* need rwx access to final directory */
	}

	if (access("/", mode)) {
		/* we do not have proper access to root, leave with error */
		goto out;
	}

	if (len == 1) {
		/* the entire path is just "/" and we have rwx access to it */
		goto ok;
	}

	do {
		/* repair any previous damage to partial-path */
		*ptr++ = '/';
		if ((ptr = strchr(ptr, '/')) == NULL) {
			/* have last component in string, ptr is
				now NULL to exit loop */
			/* need rwx access to final directory */
			mode |= R_OK | W_OK;
		} else {
			/* still have subdirectories to follow,
				isolate this subdir */
			*ptr = '\0';
		}
		if (access(partial_path, mode)) {
			/* don't have desired access to this subdirectory */
			if (mkdir(partial_path, 0744)) {
				/* can't create this subdirectory,
					return an error */
				printf("Unable to create directory %s: %s\n",
					   partial_path, strerror(errno));
				goto out;
			}
		}
	}
	while (ptr);

  ok:
	retval = 0;

  out:
	free(partial_path);

  early_out:
	return retval;
}

/*	write a magic line to the proc file system to cause the scsi
 *	mid-level to redo the inquiry for our device
 */
void
do_inquiry(int add, int host_no, int target_no, int lun_no)
{
	int fd, n, len, ret = 0;
	static char *file_name = "/proc/scsi/scsi";
	char text_line[128];

	TRACE(TRACE_DEBUG, "Entering do_inquiry\n");

	if ((fd = open(file_name, O_RDWR)) < 0) {
		perror(file_name);
		return;
	}

	TRACE(TRACE_DEBUG, "do_inquiry file_name: %s\n", file_name);

	len = sprintf(text_line, "scsi %s-single-device %d 0 %d %d",
				  add ? "add" : "remove", host_no,
				  target_no, lun_no);

	len++;	/* for writing the last null character */

	TRACE(TRACE_DEBUG, "write to scsi: %s\n", text_line);

	if ((n = write(fd, text_line, len)) < 0) {
#ifdef CONF_ISCSI_DEBUG
		perror(file_name);
#endif							/* CONF_ISCSI_DEBUG */
	} else if (n != len && n != 0)
		printf("%s: wrote %d bytes, expected %d\n", file_name, n, len);
	/* FEATURE - ADD DEVICE ENTRY */
	else {
		if (add) {
			if (access(UNH_ISCSI_DEV_DIR, R_OK | W_OK | X_OK)) {
				ret = make_full_path_dir(UNH_ISCSI_DEV_DIR);
				//ret = mkdir(UNH_ISCSI_DEV_DIR, 0744);
				if (ret) {
					goto out;
				}
			}

			sprintf(target_dir, "%s/%d", UNH_ISCSI_DEV_DIR,
				target_no);
			if (access(target_dir, R_OK | W_OK | X_OK)) {
				ret = make_full_path_dir(target_dir);
				//ret = mkdir(target_dir, 0744);
				if (ret) {
					goto out;
				}
			}

			/* Remove old device files */
			sprintf(cmd, "/bin/rm -rf %s/%d/l%d*",
					UNH_ISCSI_DEV_DIR, target_no, lun_no);
			ret = system(cmd);
			if (ret) {
				printf("Unable to remove old device files.\n");