iscsi-network-boot.c

ISCSI user client software.Client would be used to access the IPSAN server.

/*
 * iSCSI driver for Linux
 * Copyright (C) 2002 Cisco Systems, Inc.
 * maintained by [e-mail]
 *
 * 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 of the License, 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.
 *
 * See the file COPYING included with this distribution for more details.
 *
 * $Id: iscsi-network-boot.c,v 1.17 2005/02/14 09:14:02 smithan Exp $
 *
 */
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <sys/stat.h>
#include <net/route.h>

#include "iscsi-sfnet.h"
#include "iscsi-ioctl.h"
#include "iscsid.h"
#include "iscsi-login.h"
#include "iscsi-network-boot.h"

#define ISCSI_DEVICE "/dev/iscsictl"
#define NETDEV_BOOT_SETUP_MAX 8

static int control_fd = -1;
static char inbp_interface_name[IFNAMSIZ];

static int
open_control_device(void)
{
	FILE *f = NULL;
	char devname[256], buf[256];
	int devn, ctlfd;

	/*
	 * Establish the control path to the driver
	 */
	f = fopen("/proc/devices", "r");
	if (!f) {
		perror("Cannot open control path to the driver");
		return -1;
	}
	devn = 0;
	while (!feof(f)) {
		if (!fgets(buf, sizeof (buf), f)) {
			break;
		}
		if (sscanf(buf, "%d %s", &devn, devname) != 2) {
			continue;
		}
		if (!strcmp(devname, "iscsictl")) {
			break;
		}
		devn = 0;
	}
	fclose(f);
	if (!devn) {
		printf
		    ("cannot find iscsictl in /proc/devices - make "
		     "sure the module is loaded");
		return -1;
	}
	unlink(ISCSI_DEVICE);
	if (mknod(ISCSI_DEVICE, (S_IFCHR | 0600), (devn << 8))) {
		printf("cannot create %s ", ISCSI_DEVICE);
		return -1;
	}
	ctlfd = open(ISCSI_DEVICE, O_RDWR);
	if (ctlfd < 0) {
		printf("cannot open %s", ISCSI_DEVICE);
		return -1;
	}
	return ctlfd;
}

static char *
get_initiatorname(char *pathname)
{
	FILE *f = NULL;
	int c;
	char *line, buffer[1024], *name = NULL;

	if (!pathname) {
		printf("No pathname to load InitiatorName from");
		return NULL;
	}

	/* get the InitiatorName */
	if ((f = fopen(pathname, "r"))) {
		while ((line = fgets(buffer, sizeof (buffer), f))) {

			while (line && isspace(c = *line))
				line++;

			if (strncmp(line, "InitiatorName=", 14) == 0) {
				char *end = line + 14;

				/* the name is everything up to the first bit
				 * of whitespace
				 */
				while (*end && (!isspace(c = *end)))
					end++;

				if (isspace(c = *end))
					*end = '\0';

				if (end > line + 14)
					name = strdup(line + 14);
			}
		}
		fclose(f);
		if (!name) {
			printf
			    ("an InitiatorName is required, but was not "
			     "found in %s",
			     pathname);
			return NULL;
		} else {
			printf("InitiatorName=%s\n", name);
		}
		return name;
	} else {
		printf("cannot open InitiatorName configuration file %s",
		       pathname);
		return NULL;
	}
}

/*
 * Assumptions for network boot:
 * 1. Only one portal available which comes from nbp structure 
 * 2. No authentication is used.
 * 3. Digest values are not configurable on initiator side, user can set it on
 *    target if required.
 * 4. Tag is always 1, as there is no value in nbp specifying portal tag.
 * 5. Initiator name for boot and normal sessions will be different(FIXME).
 */

/* Returns 0 on success, non zero on failure */
static int
ioctl_establish_session(struct sapiNBP *nbp)
{
	int rc, ret = 0;
	struct iscsi_session_ioctl *ioctld = NULL;
	struct sockaddr_in *addr;

	/* allocate an ioctl structure with enough space
	 * for all of the portal info
	 */
	ioctld =
	    calloc(1, sizeof (*ioctld) + sizeof (struct iscsi_portal_info));
	if (ioctld == NULL) {
		printf("failed to allocate %d bytes for ioctl data structure",
		       sizeof (*ioctld) + sizeof (struct iscsi_portal_info));
		return 1;
	}

	ioctld->ioctl_version = ISCSI_SESSION_IOCTL_VERSION;
	ioctld->config_number = 1;
	ioctld->update = 0;

	ioctld->portal.login_timeout = 15;
	ioctld->portal.auth_timeout = 45;
	ioctld->portal.active_timeout = 5;
	ioctld->portal.idle_timeout = 60;
	ioctld->portal.ping_timeout = 5;
	ioctld->portal.replacement_timeout = 0;

	ioctld->portal.abort_timeout = 10;
	ioctld->portal.reset_timeout = 30;

	ioctld->portal.initial_r2t = 0;
	ioctld->portal.immediate_data = 0;
	ioctld->portal.max_recv_data_segment_len = 128 * 1024;
	ioctld->portal.first_burst_len = 256 * 1024;
	ioctld->portal.max_burst_len = (16 * 1024 * 1024) - 1024;
	ioctld->portal.def_time2wait = 0;
	ioctld->portal.def_time2retain = 0;
	ioctld->portal.data_digest = ISCSI_DIGEST_NONE_CRC32C;
	ioctld->portal.header_digest = ISCSI_DIGEST_NONE_CRC32C;
	ioctld->portal.tcp_window_size = 256 * 1024;

	addr = (struct sockaddr_in *)&ioctld->portal.addr;
	addr->sin_family = AF_INET;
	memcpy(&addr->sin_addr.s_addr, (char *)(&nbp->targetipaddr),
	       sizeof(nbp->targetipaddr));

	addr->sin_port = htons(nbp->tcpport);
	ioctld->portal.tag = PORTAL_GROUP_TAG_UNKNOWN;

	ioctld->password_length = 0;
	ioctld->password_length_in = 0;
	printf("authentication not configured for target");

	strcpy(ioctld->initiator_name,
	       get_initiatorname("/etc/initiatorname.iscsi"));
	strcpy(ioctld->target_name, nbp->targetstring);

	ioctld->isid[0] = DRIVER_ISID_0;
	ioctld->isid[1] = DRIVER_ISID_1;
	ioctld->isid[2] = DRIVER_ISID_2;
	ioctld->isid[3] = 0;
	ioctld->isid[4] = 0;
	ioctld->isid[5] = 1;


	/*
	 * Tell the kernel to establish a session.
	 */
	do {
		rc = ioctl(control_fd, ISCSI_ESTABLISH_SESSION,
			   (char *) ioctld);
		if (rc < 0) {
			printf("iSCSI session ioctl failed for %s, errno = %d",
			       nbp->targetstring, errno);
			printf
			    ("\nRetrying session establishment with "
			     "the boot disk ...\n");
			sleep(2);
		} else {
			printf
			    ("iSCSI session ioctl for %s returned from "
			     "kernel with rc %d",
			     nbp->targetstring, rc);
		}
	       
	} while (rc < 0);

	memset(&ioctld, 0, sizeof (ioctld));

	return ret;
}

static int
find_pxe_sig(char *buf, int iter, struct sapiNBP *nbp)
{
	int len, i = 0;
	char *p = buf, *sig = SIGNATURE;

	len = strlen(sig);
	while (INBP_BUF_SIZE - i >= len) {
		if (strncmp(p, sig, len) == 0) {
			printf("\nGot the signature at 0x%x\n",
			       iter * INBP_BUF_SIZE + i);
			memcpy(nbp, p, sizeof (struct sapiNBP));
			printf("targetname: %s\n\n", nbp->targetstring);
			return 1;
		}
		p++;
		i++;
	}
	return 0;
}

void
get_inbp_info(struct sapiNBP *nbp)
{
	int fd, i = 0;
	char buf[1024];

	if ((fd = open("/dev/mem", O_RDONLY)) < 0) {
		perror("open mem");
		return;
	}
	while (i < SCANAREA) {
		if (read(fd, buf, INBP_BUF_SIZE) < 0) {
			printf("Read error at 0x%x\n", i * INBP_BUF_SIZE);
			perror("read");
			return;
		}
		i++;
		/* printf("Reading %dk area..\n", i); */
		if (find_pxe_sig(buf, i, nbp))
			break;
	}

	if (i > SCANAREA) {
		printf("\n%s not found, iscsi boot will fail !!!\n", SIGNATURE);
		sleep(10);
	}

}


/* Returns 0 on success, non zero on error */
static int
iscsi_add_route(struct sapiNBP *nbp)
{
	struct rtentry rt;
	struct sockaddr_in *dst = (struct sockaddr_in *) &rt.rt_dst;
	struct sockaddr_in *gw = (struct sockaddr_in *) &rt.rt_gateway;
	char dev[IFNAMSIZ], ip[16];
	int ret, fd;

	memset((char *) &rt, 0, sizeof (struct rtentry));
	memset(ip, 0, 16);
	memset(dev, 0, IFNAMSIZ);

	dst->sin_family = AF_INET;
	dst->sin_addr.s_addr = INADDR_ANY;

	strcpy(ip, (char *) (&nbp->ripaddr));
	strcpy(dev, inbp_interface_name);

	gw->sin_family = AF_INET;
	memcpy(&gw->sin_addr.s_addr, ip, 4);

	rt.rt_flags = (RTF_UP | RTF_GATEWAY);
	rt.rt_dev = dev;

	fd = socket(AF_INET,SOCK_STREAM,0);
	if (fd == -1) {
		printf("\nFailed to create socket with errno %d\n", errno);
		return 1;
	}

	ret = ioctl(fd, SIOCADDRT, &rt);

	if(ret != 0)
		printf("iSCSI: error in setting the route, ioctl returned "
		       "with value: %d\n", ret);

	return ret;
}


/* Returns 1 on success 0 on failure */
static int
iscsi_set_if_addr(struct sapiNBP *nbp)
{
	struct ifreq ifr;
	struct sockaddr sa;
	struct sockaddr_in *sin = (struct sockaddr_in *) &sa;
	int dev_ret = 0, fd;

	memset(&ifr, 0, sizeof (struct ifreq));
	memset(&sa, 0, sizeof (struct sockaddr));

	if (nbp->myipaddr != 0) {
		memcpy(&sin->sin_addr,
		       (char *)&nbp->myipaddr, 4);
	} else {
		printf("\nERROR !!! Not setting ip from inbp !!!\n");
		return 0;
	}
	if (inbp_interface_name != NULL) {
		strcpy(ifr.ifr_name, inbp_interface_name);
	} else {
		printf("\nERROR !!! Not setting interface from inbp !!!\n");
		return 0;
	}

	fd = socket(AF_INET,SOCK_STREAM,0);
	if (fd == -1) {
		printf("\nFailed to create socket with errno %d\n", errno);
		return 0;
	}

	/* Check if the interface is already up or not */
	if (ioctl(fd, SIOCGIFFLAGS, &ifr) == 0) {
		if ((ifr.ifr_flags & IFF_UP) != 0) {
			printf
			    ("\nInterface %s has IFF_UP flag already set\n",
			     ifr.ifr_name);
			return 1;
		}
	} else {
		printf
		    ("\niSCSI: ERROR in getting interface FLAGS for "
		     "interface %s\n",
		     ifr.ifr_name);
		return 0;
	}

	memset(&ifr, 0, sizeof (struct ifreq));
	strcpy(ifr.ifr_name, inbp_interface_name);

	sin->sin_family = AF_INET;
	sin->sin_port = 0;

	memcpy(&ifr.ifr_addr, &sa, sizeof (struct sockaddr));

	if ((dev_ret = ioctl(fd, SIOCSIFADDR, (void *) &ifr)) != 0) {
		printf
		    ("\niSCSI: ERROR in setting ip address for interface %s\n",
		     ifr.ifr_name);
		return 0;
	}

	memset(&ifr, 0, sizeof (struct ifreq));

	if (inbp_interface_name != NULL) {
		strcpy(ifr.ifr_name, inbp_interface_name);
	} else {
		printf("\nERROR !!! Not setting interface from inbp !!!\n");
		return 0;
	}

	ifr.ifr_flags |= IFF_UP | IFF_BROADCAST | IFF_RUNNING | IFF_MULTICAST;

	if ((dev_ret = ioctl(fd, SIOCSIFFLAGS, (void *) &ifr)) != 0) {
		printf("\niSCSI: ERROR in setting flags for interface %s\n",
		       ifr.ifr_name);
		return 0;
	}

	memset(&ifr, 0, sizeof (struct ifreq));

	strcpy(ifr.ifr_name, inbp_interface_name);
	memcpy(&sin->sin_addr, &nbp->myipmask,
	       4);
	memcpy(&ifr.ifr_netmask, &sa,
	       sizeof (struct sockaddr));

	if ((dev_ret = ioctl(fd, SIOCSIFNETMASK, (void *) &ifr)) != 0) {
		printf
		    ("\niSCSI: ERROR in setting network mask "
		     "for interface %s\n",
		     ifr.ifr_name);
		return 0;
	}

	while (iscsi_add_route(nbp)) {
		printf("\niSCSI: iscsi_set_if_addr: iscsi_add_route failed\n");
		sleep(2);
	}

	return 1;
}


/* Return 1 on sucess, 0 on error.*/
int
bring_up_network(struct sapiNBP *nbp)
{
	int fd, tmp_index;
	struct ifreq req;

	fd = socket(AF_INET,SOCK_STREAM,0);
	if (fd == -1) {
		printf("/n failed to create socket with errno %d\n", errno);
		return 0;
    	}

    	for (tmp_index = 1; tmp_index < NETDEV_BOOT_SETUP_MAX; tmp_index++) {
		memset(&req,0,sizeof(req));
		req.ifr_ifindex = tmp_index;
		if (ioctl(fd, SIOCGIFNAME, &req) < 0) {
			printf("iSCSI: error in getting interface name\n");
			return 0;
		}
		req.ifr_ifindex = 0;

		if (ioctl(fd, SIOCGIFHWADDR, &req) < 0) {
			printf("iSCSI: error in getting hardware address\n");
			return 0;
		}

		if (!memcmp(nbp->myethaddr, req.ifr_hwaddr.sa_data,
			    IFHWADDRLEN)){
			strcpy(inbp_interface_name, req.ifr_name);
			break;
		}
	}

	while(!iscsi_set_if_addr(nbp)) {
		printf("\niSCSI: iscsi_set_if_addr failed\n");
	}

	return 1;
}

void
establish_iscsi_network_boot_session(struct sapiNBP *nbp)
{
	int rv = 0;

	/* ensure the control device exists, and open it for all of
	 * the child processes to use
	 */
	for (;;) {
		control_fd = open_control_device();
		if (control_fd >= 0)
			break;
		printf
		    ("could not open control device %s. Make sure "
		     "iscsi is loaded",
		     ISCSI_DEVICE);
		sleep(5);
	}

	do {
		rv = ioctl_establish_session(nbp);
		if (rv != 0) {
			printf("ISCSI_ESTABLISH_SESSION ioctl for %s failed, "
			       "returned from kernel with rv %d",
			       nbp->targetstring, rv);
		}
	} while (rv != 0);
}