second/file.c - yaboot - Rivoreo Source Code Repositories

 /*
  *  file.c - Filesystem related interfaces
  *
  *  Copyright (C) 2001, 2002 Ethan Benson
  *
  *  parse_device_path()
  *
  *  Copyright (C) 2001 Colin Walters
  *
  *  Copyright (C) 1999 Benjamin Herrenschmidt
  *
  *  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.
  *
  *  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.
  */

 #include "ctype.h"
 #include "types.h"
 #include "stddef.h"
 #include "stdlib.h"
 #include "file.h"
 #include "prom.h"
 #include "string.h"
 #include "partition.h"
 #include "fs.h"
 #include "errors.h"
 #include "debug.h"

 extern char bootdevice[];

 /* Convert __u32 into std, dotted quad string, leaks like a sive :( */
 static char *
 ipv4_to_str(__u32 ip)
 {
      char *buf = malloc(sizeof("000.000.000.000"));

      sprintf(buf,"%u.%u.%u.%u",
              (ip & 0xff000000) >> 24, (ip & 0x00ff0000) >> 16,
              (ip & 0x0000ff00) >>  8, (ip & 0x000000ff));

      return buf;
 }

 /* Ensure the string arg is a plausible IPv4 address */
 static char * is_valid_ipv4_str(char *str)
 {
      int i;
      long tmp;
      __u32 ip = 0;
      char *ptr=str, *endptr;

      if (str == NULL)
           return NULL;

      for (i=0; i<4; i++, ptr = ++endptr) {
           tmp = strtol(ptr, &endptr, 10);
           if ((tmp & 0xff) != tmp)
                return NULL;

           /* If we reach the end of the string but we're not in the 4th octet
            * we have an invalid IP */
           if (*endptr == '\x0' && i!=3)
                return NULL;

           /* If we have anything other than a NULL or '.' we have an invlaid
            * IP */
           if (*endptr != '\x0' && *endptr != '.')
                return NULL;

           ip += (tmp << (24-(i*8)));
      }

      if (ip == 0 || ip == ~0u)
           return NULL;

      return str;
 }


 /*
  * Copy the string from source to dest until the end of string or comma is seen
  * in the source.
  * Move source and dest pointers respectively.
  * Returns pointer to the start of the string that has just been copied.
  */
 static char *
 scopy(char **dest, char **source)
 {
      char *ret = *dest;

      if (!**source)
 	  return NULL;

      while (**source != ',' && **source != '\0')
 	  *(*dest)++ = *(*source)++;
      if (**source != '\0')
 	  (void)*(*source)++;
      **dest = '\0';
      (void)*(*dest)++;
      return ret;
 }

 /*
  * Extract all the ipv4 arguments from the bootpath provided and fill result
  * Returns 1 on success, 0 on failure.
  */
 static int
 extract_ipv4_args(char *imagepath, struct boot_fspec_t *result)
 {
      char *tmp, *args, *str, *start;

      args = strrchr(imagepath, ':');
      if (!args)
 	  return 1;

      start = args; /* used to see if we read any optional parameters */

      /* The obp-tftp device arguments should be at the end of
       * the argument list.  Skip over any extra arguments (promiscuous,
       * speed, duplex, bootp, rarp).
       */

      tmp = strstr(args, "promiscuous");
      if (tmp && tmp > args)
 	  args = tmp + strlen("promiscuous");

      tmp = strstr(args, "speed=");
      if (tmp && tmp > args)
 	  args = tmp + strlen("speed=");

      tmp = strstr(args, "duplex=");
      if (tmp && tmp > args)
 	  args = tmp + strlen("duplex=");

      tmp = strstr(args, "bootp");
      if (tmp && tmp > args)
 	  args = tmp + strlen("bootp");

      tmp = strstr(args, "rarp");
      if (tmp && tmp > args)
 	  args = tmp + strlen("rarp");

      if (args != start) /* we read some parameters, so go past the next comma(,) */
 	  args = strchr(args, ',');
      if (!args)
 	  return 1;

      str = malloc(strlen(args) + 1); /*long enough to hold all strings */
      if (!str)
 	  return 0;

      if (args[-1] != ':')
 	  args++; /* If comma(,) is not immediately followed by ':' then go past the , */

      /*
       * read the arguments in order: siaddr,filename,ciaddr,giaddr,
       * bootp-retries,tftp-retries,addl_prameters
       */
      result->siaddr = is_valid_ipv4_str(scopy(&str, &args));
      result->file = scopy(&str, &args);
      result->ciaddr = is_valid_ipv4_str(scopy(&str, &args));
      result->giaddr = is_valid_ipv4_str(scopy(&str, &args));
      result->bootp_retries = scopy(&str, &args);
      result->tftp_retries = scopy(&str, &args);
      result->subnetmask = is_valid_ipv4_str(scopy(&str, &args));
      if (*args) {
 	  result->addl_params = strdup(args);
 	  if (!result->addl_params)
 		return 0;
      }
      return 1;
 }

 /* DHCP options */
 enum dhcp_options {
      DHCP_PAD = 0,
      DHCP_NETMASK = 1,
      DHCP_ROUTERS = 3,
      DHCP_END = 255,
 };

 #define DHCP_COOKIE        0x63825363
 #define DHCP_COOKIE_SIZE   4

 /*
  * Process the bootp reply packet's vendor extensions.
  * Vendor extensions are detailed in: http://www.faqs.org/rfcs/rfc1084.html
  */
 static void
 extract_vendor_options(struct bootp_packet *packet, struct boot_fspec_t *result)
 {
      int i = 0;
      __u32 cookie;
      __u8 *options = &packet->options[0];

      memcpy(&cookie, &options[i], DHCP_COOKIE_SIZE);

      if (cookie != DHCP_COOKIE) {
           prom_printf("EEEK! cookie is fubar got %08x expected %08x\n",
                       cookie, DHCP_COOKIE);
           return;
      }

      i += DHCP_COOKIE_SIZE;

      /* FIXME: It may be possible to run off the end of a packet here /if/
       *         it's malformed. :( */
      while (options[i] != DHCP_END) {
           __u8 tag = options[i++], len;
           __u32 value = 0;

           if (tag == DHCP_PAD)
                continue;

           len = options[i++];
           /* Clamp the maxium length of the memcpy() to the right size for
            * value. */
           if (len > sizeof(value))
                memcpy(&value, &options[i], sizeof(value));
           else
                memcpy(&value, &options[i], len);

 #if DEBUG
 {
      DEBUG_F("tag=%2d, len=%2d, data=", tag, len);
      int j;
      for (j=0; j<len; j++)
           prom_printf("%02x", options[i+j]);
      prom_printf("\n");
 }
 #endif

           switch (tag) {
                case DHCP_NETMASK:
                     if ((result->subnetmask == NULL ||
                          *(result->subnetmask) == '\x0') && value != 0) {
                          result->subnetmask = ipv4_to_str(value);
                          DEBUG_F("Storing %s as subnetmask from options\n",
                                  result->subnetmask);
                     }
                     break;
                case DHCP_ROUTERS:
                     if ((result->giaddr == NULL || *(result->giaddr) == '\x0')
                         && value != 0) {
                          result->giaddr = ipv4_to_str(value);
                          DEBUG_F("Storing %s as gateway from options\n",
                                  result->giaddr);
                     }
                     break;
                }
           i += len;
      }
 }

 /*
  * Check netinfo for ipv4 parameters and add them to the fspec iff the
  * fspec has no existing value.
  */
 static void
 extract_netinfo_args(struct boot_fspec_t *result)
 {
      struct bootp_packet *packet;

      /* Check to see if we can get the [scyg]iaddr fields from netinfo */
      packet = prom_get_netinfo();
      if (!packet)
           return;

      DEBUG_F("We have a boot packet\n");
      DEBUG_F(" siaddr = <%x>\n", packet->siaddr);
      DEBUG_F(" ciaddr = <%x>\n", packet->ciaddr);
      DEBUG_F(" yiaddr = <%x>\n", packet->yiaddr);
      DEBUG_F(" giaddr = <%x>\n", packet->giaddr);

      /* Try to fallback to yiaddr if ciaddr is empty. Broken? */
      if (packet->ciaddr == 0 && packet->yiaddr != 0)
           packet->ciaddr = packet->yiaddr;

      if ((result->siaddr == NULL || *(result->siaddr) == '\x0')
          && packet->siaddr != 0)
           result->siaddr = ipv4_to_str(packet->siaddr);
      if ((result->ciaddr == NULL || *(result->ciaddr) == '\x0')
          && packet->ciaddr != 0)
           result->ciaddr = ipv4_to_str(packet->ciaddr);
      if ((result->giaddr == NULL || *(result->giaddr) == '\x0')
          && packet->giaddr != 0)
           result->giaddr = ipv4_to_str(packet->giaddr);

      extract_vendor_options(packet, result);

      /* FIXME: Yck! if we /still/ do not have a gateway then "cheat" and use
       *        the server.  This will be okay if the client and server are on
       *        the same IP network, if not then lets hope the server does ICMP
       *        redirections */
      if (result->giaddr == NULL) {
           result->giaddr = ipv4_to_str(packet->siaddr);
           DEBUG_F("Forcing giaddr to siaddr <%s>\n", result->giaddr);
      }
 }

 /*
  * Extract all the ipv6 arguments from the bootpath provided and fill result
  * Syntax: ipv6,[dhcpv6[=diaddr,]]ciaddr=c_iaddr,giaddr=g_iaddr,siaddr=s_iaddr,
  *      filename=file_name,tftp-retries=tftp_retries,blksize=block_size
  * Returns 1 on success, 0 on failure.
  */
 static int
 extract_ipv6_args(char *imagepath, struct boot_fspec_t *result)
 {
      char *str, *tmp;
      int total_len;

      result->is_ipv6 = 1;

      /* Just allocate the max required size */
      total_len = strlen(imagepath) + 1;
      str = malloc(total_len);
      if (!str)
 	return 0;

      if ((tmp = strstr(imagepath, "dhcpv6=")) != NULL)
 	result->dhcpv6 = scopy(&str, &tmp);

      if ((tmp = strstr(imagepath, "ciaddr=")) != NULL)
 	result->ciaddr = scopy(&str, &tmp);

      if ((tmp = strstr(imagepath, "giaddr=")) != NULL)
 	result->giaddr = scopy(&str, &tmp);

      if ((tmp = strstr(imagepath, "siaddr=")) != NULL)
 	result->siaddr = scopy(&str, &tmp);

      if ((tmp = strstr(imagepath, "filename=")) != NULL)
 	result->file = scopy(&str, &tmp);

      if ((tmp = strstr(imagepath, "tftp-retries=")) != NULL)
 	result->tftp_retries = scopy(&str, &tmp);

      if ((tmp = strstr(imagepath, "blksize=")) != NULL)
 	result->blksize = scopy(&str, &tmp);

      return 1;
 }

 /*
  * Extract all the arguments provided in the imagepath and fill it in result.
  * Returns 1 on success, 0 on failure.
  */
 static int
 extract_netboot_args(char *imagepath, struct boot_fspec_t *result)
 {
      int ret;

      DEBUG_F("imagepath = %s\n", imagepath);

      if (!imagepath)
 	  return 1;

      if (strstr(imagepath, TOK_IPV6))
 	  ret = extract_ipv6_args(imagepath, result);
      else
 	  ret = extract_ipv4_args(imagepath, result);
      extract_netinfo_args(result);

      DEBUG_F("ipv6 = <%d>\n", result->is_ipv6);
      DEBUG_F("siaddr = <%s>\n", result->siaddr);
      DEBUG_F("file = <%s>\n", result->file);
      DEBUG_F("ciaddr = <%s>\n", result->ciaddr);
      DEBUG_F("giaddr = <%s>\n", result->giaddr);
      DEBUG_F("bootp_retries = <%s>\n", result->bootp_retries);
      DEBUG_F("tftp_retries = <%s>\n", result->tftp_retries);
      DEBUG_F("addl_params = <%s>\n", result->addl_params);
      DEBUG_F("dhcpv6 = <%s>\n", result->dhcpv6);
      DEBUG_F("blksize = <%s>\n", result->blksize);

      return ret;
 }

 static char *netdev_path_to_dev(const char *path)
 {
      char *dev, *tmp;
      size_t len;

      DEBUG_F("path = %s\n", path);

      if (!path)
 	  return NULL;

      tmp = strchr(path, ':');
      if (!tmp)
 	  return strdup(path);
      tmp++;

      len = tmp - path + 1;

      dev = malloc(len);
      if (dev) {
 	  strncpy(dev, path, len);
 	  dev[len - 1] = '\0';
      }
      return dev;
 }

 /* This function follows the device path in the devtree and separates
    the device name, partition number, and other datas (mostly file name)
    the string passed in parameters is changed since 0 are put in place
    of some separators to terminate the various strings.

    when a default device is supplied imagepath will be assumed to be a
    plain filename unless it contains a : otherwise if defaultdev is
    NULL imagepath will be assumed to be a device path.

    returns 1 on success 0 on failure.

    Supported examples:
     - /pci@80000000/pci-bridge@d/ADPT,2930CU@2/@1:4
     - /pci@80000000/pci-bridge@d/ADPT,2930CU@2/@1:4,/boot/vmlinux
     - hd:3,/boot/vmlinux
     - enet:10.0.0.1,/tftpboot/vmlinux
     - enet:,/tftpboot/vmlinux
     - enet:bootp
     - enet:0
     - arguments for obp-tftp open as specified in section 4.1 of
       http://playground.sun.com/1275/practice/obp-tftp/tftp1_0.pdf
       [bootp,]siaddr,filename,ciaddr,giaddr,bootp-retries,tftp-retries
       ex: enet:bootp,10.0.0.11,bootme,10.0.0.12,10.0.0.1,5,5
    Supported only if defdevice == NULL
     - disc
     - any other device path lacking a :
    Unsupported examples:
     - hd:2,\\:tbxi <- no filename will be detected due to the extra :
     - enet:192.168.2.1,bootme,c-iaddr,g-iaddr,subnet-mask,bootp-retries,tftp-retries */

 int
 parse_device_path(char *imagepath, char *defdevice, int defpart,
 		  char *deffile, struct boot_fspec_t *result)
 {
      char *ptr;
      char *ipath = NULL;
      char *defdev = NULL;
      int device_kind = -1;

      DEBUG_F("imagepath = %s; defdevice %s; defpart %d, deffile %s\n",
 		imagepath, defdevice, defpart, deffile);

      result->dev = NULL;
      result->part = -1;
      result->file = NULL;

      if (!imagepath)
 	  return 0;

       /*
        * Do preliminary checking for an iscsi device; it may appear as
        * pure a network device (device_type == "network") if this is
        * ISWI.  This is the case on IBM systems doing an iscsi OFW
        * boot.
        */
      if (strstr(imagepath, TOK_ISCSI)) {
  	  /*
 	   * get the virtual device information from the
 	   * "nas-bootdevice" property.
 	   */
  	  if (prom_get_chosen("nas-bootdevice", bootdevice, BOOTDEVSZ)) {
 	       DEBUG_F("reset boot-device to"
 		       " /chosen/nas-bootdevice = %s\n", bootdevice);
 	       device_kind = FILE_DEVICE_ISCSI;
 	       ipath = strdup(bootdevice);
 	       if (!ipath)
 		    return 0;
  	  }
  	  else
  	       return 0;
      }
      else if (!(ipath = strdup(imagepath)))
 	  return 0;

      if (defdevice) {
 	  defdev = strdup(defdevice);
 	  device_kind = prom_get_devtype(defdev);
      } else if (device_kind == -1)
 	  device_kind = prom_get_devtype(ipath);

      /*
       * When an iscsi iqn is present, it may have embedded colons, so
       * don't parse off anything.
       */
      if (device_kind != FILE_DEVICE_NET &&
 	 device_kind != FILE_DEVICE_ISCSI &&
 	 strchr(defdev, ':') != NULL) {
            if ((ptr = strrchr(defdev, ':')) != NULL)
                 *ptr = 0; /* remove trailing : from defdevice if necessary */
      }

      /* This will not properly handle an obp-tftp argument list
       * with elements after the filename; that is handled below.
       */
      if (device_kind != FILE_DEVICE_NET &&
 	 device_kind != FILE_DEVICE_ISCSI &&
 	 strchr(ipath, ':') != NULL) {
 	  if ((ptr = strrchr(ipath, ',')) != NULL) {
 	       char *colon = strrchr(ipath, ':');
 	       /* If a ':' occurs *after* a ',', then we assume that there is
 		  no filename */
 	       if (!colon || colon < ptr) {
 		    result->file = strdup(ptr+1);
 		    /* Trim the filename off */
 		    *ptr = 0;
 	       }
 	  }
      }

      if (device_kind == FILE_DEVICE_NET) {
 	  if (strchr(ipath, ':')) {
 	       if (extract_netboot_args(ipath, result) == 0)
 		   return 0;
 	  } else {
                /* If we didn't get a ':' then look only in netinfo */
 	       extract_netinfo_args(result);
 	       result->file = strdup(ipath);
           }

 	  if (!defdev)
 	       result->dev = netdev_path_to_dev(ipath);
      } else if (device_kind != FILE_DEVICE_ISCSI &&
 		(ptr = strrchr(ipath, ':')) != NULL) {
 	  *ptr = 0;
 	  result->dev = strdup(ipath);
 	  if (*(ptr+1))
 	       result->part = simple_strtol(ptr+1, NULL, 10);
      } else if (!defdev) {
 	  result->dev = strdup(ipath);
      } else if (strlen(ipath)) {
           result->file = strdup(ipath);
      } else {
 	  free(defdev);
 	  return 0;
      }

      if (!result->dev && defdev)
 	  result->dev = strdup(defdev);

      if (result->part < 0)
 	  result->part = defpart;

      if (!result->file)
 	  result->file = strdup(deffile);

      free(ipath);
      if (defdev)
           free(defdev);
      return 1;
 }


 static int
 file_block_open(	struct boot_file_t*	file,
 			struct boot_fspec_t*	fspec,
 			int			partition)
 {
      struct partition_t*	parts;
      struct partition_t*	p;
      struct partition_t*	found;

      parts = partitions_lookup(fspec->dev);
      found = NULL;

 #if DEBUG
      if (parts)
 	  prom_printf("partitions:\n");
      else
 	  prom_printf("no partitions found.\n");
 #endif
      for (p = parts; p && !found; p=p->next) {
 	  DEBUG_F("number: %02d, start: 0x%08lx, length: 0x%08lx\n",
 		  p->part_number, p->part_start, p->part_size );
 	  if (partition == -1) {
 	       file->fs = fs_open( file, p, fspec );
 	       if (file->fs == NULL || fserrorno != FILE_ERR_OK)
 		    continue;
 	       else {
 		    partition = p->part_number;
 		    goto done;
 	       }
 	  }
 	  if ((partition >= 0) && (partition == p->part_number))
 	       found = p;
 #if DEBUG
 	  if (found)
 	       prom_printf(" (match)\n");
 #endif
      }

      /* Note: we don't skip when found is NULL since we can, in some
       * cases, let OF figure out a default partition.
       */
      DEBUG_F( "Using OF defaults.. (found = %p)\n", found );
      file->fs = fs_open( file, found, fspec );

 done:
      if (parts)
 	  partitions_free(parts);

      return fserrorno;
 }

 static int
 file_net_open(struct boot_file_t* file, struct boot_fspec_t *fspec)
 {
      file->fs = fs_of_netboot;
      return fs_of_netboot->open(file, NULL, fspec);
 }

 static int
 default_read(	struct boot_file_t*	file,
 		unsigned int		size,
 		void*			buffer)
 {
      prom_printf("WARNING ! default_read called !\n");
      return FILE_ERR_EOF;
 }

 static int
 default_seek(	struct boot_file_t*	file,
 		unsigned int		newpos)
 {
      prom_printf("WARNING ! default_seek called !\n");
      return FILE_ERR_EOF;
 }

 static int
 default_close(	struct boot_file_t*	file)
 {
      prom_printf("WARNING ! default_close called !\n");
      return FILE_ERR_OK;
 }

 static struct fs_t fs_default =
 {
      "defaults",
      NULL,
      default_read,
      default_seek,
      default_close
 };


 int open_file(struct boot_fspec_t* spec, struct boot_file_t* file)
 {
      int result;

      memset(file, 0, sizeof(struct boot_file_t*));
      file->fs        = &fs_default;

      DEBUG_F("dev_path = %s\nfile_name = %s\npartition = %d\n",
 	     spec->dev, spec->file, spec->part);

      result = prom_get_devtype(spec->dev);
      if (result > 0)
 	  file->device_kind = result;
      else
 	  return result;

      switch(file->device_kind) {
      case FILE_DEVICE_BLOCK:
 	  DEBUG_F("device is a block device\n");
 	  return file_block_open(file, spec, spec->part);
      case FILE_DEVICE_ISCSI:
 	  DEBUG_F("device is a iSCSI device\n");
 	  return file_block_open(file, spec, spec->part);
      case FILE_DEVICE_NET:
 	  DEBUG_F("device is a network device\n");
 	  return file_net_open(file, spec);
      }
      return 0;
 }

 /*
  * Local variables:
  * c-file-style: "k&r"
  * c-basic-offset: 5
  * End:
  */
	/*
	* file.c - Filesystem related interfaces
	*
	* Copyright (C) 2001, 2002 Ethan Benson
	*
	* parse_device_path()
	*
	* Copyright (C) 2001 Colin Walters
	*
	* Copyright (C) 1999 Benjamin Herrenschmidt
	*
	* 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.
	*
	* 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.
	*/

	#include "ctype.h"
	#include "types.h"
	#include "stddef.h"
	#include "stdlib.h"
	#include "file.h"
	#include "prom.h"
	#include "string.h"
	#include "partition.h"
	#include "fs.h"
	#include "errors.h"
	#include "debug.h"

	extern char bootdevice[];

	/* Convert __u32 into std, dotted quad string, leaks like a sive :( */
	static char *
	ipv4_to_str(__u32 ip)
	{
	char *buf = malloc(sizeof("000.000.000.000"));

	sprintf(buf,"%u.%u.%u.%u",
	(ip & 0xff000000) >> 24, (ip & 0x00ff0000) >> 16,
	(ip & 0x0000ff00) >> 8, (ip & 0x000000ff));

	return buf;
	}

	/* Ensure the string arg is a plausible IPv4 address */
	static char * is_valid_ipv4_str(char *str)
	{
	int i;
	long tmp;
	__u32 ip = 0;
	char ptr=str, endptr;

	if (str == NULL)
	return NULL;

	for (i=0; i<4; i++, ptr = ++endptr) {
	tmp = strtol(ptr, &endptr, 10);
	if ((tmp & 0xff) != tmp)
	return NULL;

	/* If we reach the end of the string but we're not in the 4th octet
	* we have an invalid IP */
	if (*endptr == '\x0' && i!=3)
	return NULL;

	/* If we have anything other than a NULL or '.' we have an invlaid
	* IP */
	if (endptr != '\x0' && endptr != '.')
	return NULL;

	ip += (tmp << (24-(i*8)));
	}

	if (ip == 0 \|\| ip == ~0u)
	return NULL;

	return str;
	}


	/*
	* Copy the string from source to dest until the end of string or comma is seen
	* in the source.
	* Move source and dest pointers respectively.
	* Returns pointer to the start of the string that has just been copied.
	*/
	static char *
	scopy(char dest, char source)
	{
	char ret = dest;

	if (!**source)
	return NULL;

	while (source != ',' && source != '\0')
	(dest)++ = (source)++;
	if (**source != '\0')
	(void)(source)++;
	**dest = '\0';
	(void)(dest)++;
	return ret;
	}

	/*
	* Extract all the ipv4 arguments from the bootpath provided and fill result
	* Returns 1 on success, 0 on failure.
	*/
	static int
	extract_ipv4_args(char imagepath, struct boot_fspec_t result)
	{
	char tmp, args, str, start;

	args = strrchr(imagepath, ':');
	if (!args)
	return 1;

	start = args; /* used to see if we read any optional parameters */

	/* The obp-tftp device arguments should be at the end of
	* the argument list. Skip over any extra arguments (promiscuous,
	* speed, duplex, bootp, rarp).
	*/

	tmp = strstr(args, "promiscuous");
	if (tmp && tmp > args)
	args = tmp + strlen("promiscuous");

	tmp = strstr(args, "speed=");
	if (tmp && tmp > args)
	args = tmp + strlen("speed=");

	tmp = strstr(args, "duplex=");
	if (tmp && tmp > args)
	args = tmp + strlen("duplex=");

	tmp = strstr(args, "bootp");
	if (tmp && tmp > args)
	args = tmp + strlen("bootp");

	tmp = strstr(args, "rarp");
	if (tmp && tmp > args)
	args = tmp + strlen("rarp");

	if (args != start) /* we read some parameters, so go past the next comma(,) */
	args = strchr(args, ',');
	if (!args)
	return 1;

	str = malloc(strlen(args) + 1); /long enough to hold all strings /
	if (!str)
	return 0;

	if (args[-1] != ':')
	args++; /* If comma(,) is not immediately followed by ':' then go past the , */

	/*
	* read the arguments in order: siaddr,filename,ciaddr,giaddr,
	* bootp-retries,tftp-retries,addl_prameters
	*/
	result->siaddr = is_valid_ipv4_str(scopy(&str, &args));
	result->file = scopy(&str, &args);
	result->ciaddr = is_valid_ipv4_str(scopy(&str, &args));
	result->giaddr = is_valid_ipv4_str(scopy(&str, &args));
	result->bootp_retries = scopy(&str, &args);
	result->tftp_retries = scopy(&str, &args);
	result->subnetmask = is_valid_ipv4_str(scopy(&str, &args));
	if (*args) {
	result->addl_params = strdup(args);
	if (!result->addl_params)
	return 0;
	}
	return 1;
	}

	/* DHCP options */
	enum dhcp_options {
	DHCP_PAD = 0,
	DHCP_NETMASK = 1,
	DHCP_ROUTERS = 3,
	DHCP_END = 255,
	};

	#define DHCP_COOKIE 0x63825363
	#define DHCP_COOKIE_SIZE 4

	/*
	* Process the bootp reply packet's vendor extensions.
	* Vendor extensions are detailed in: http://www.faqs.org/rfcs/rfc1084.html
	*/
	static void
	extract_vendor_options(struct bootp_packet packet, struct boot_fspec_t result)
	{
	int i = 0;
	__u32 cookie;
	__u8 *options = &packet->options[0];

	memcpy(&cookie, &options[i], DHCP_COOKIE_SIZE);

	if (cookie != DHCP_COOKIE) {
	prom_printf("EEEK! cookie is fubar got %08x expected %08x\n",
	cookie, DHCP_COOKIE);
	return;
	}

	i += DHCP_COOKIE_SIZE;

	/* FIXME: It may be possible to run off the end of a packet here /if/
	* it's malformed. :( */
	while (options[i] != DHCP_END) {
	__u8 tag = options[i++], len;
	__u32 value = 0;

	if (tag == DHCP_PAD)
	continue;

	len = options[i++];
	/* Clamp the maxium length of the memcpy() to the right size for
	* value. */
	if (len > sizeof(value))
	memcpy(&value, &options[i], sizeof(value));
	else
	memcpy(&value, &options[i], len);

	#if DEBUG
	{
	DEBUG_F("tag=%2d, len=%2d, data=", tag, len);
	int j;
	for (j=0; j<len; j++)
	prom_printf("%02x", options[i+j]);
	prom_printf("\n");
	}
	#endif

	switch (tag) {
	case DHCP_NETMASK:
	if ((result->subnetmask == NULL \|\|
	*(result->subnetmask) == '\x0') && value != 0) {
	result->subnetmask = ipv4_to_str(value);
	DEBUG_F("Storing %s as subnetmask from options\n",
	result->subnetmask);
	}
	break;
	case DHCP_ROUTERS:
	if ((result->giaddr == NULL \|\| *(result->giaddr) == '\x0')
	&& value != 0) {
	result->giaddr = ipv4_to_str(value);
	DEBUG_F("Storing %s as gateway from options\n",
	result->giaddr);
	}
	break;
	}
	i += len;
	}
	}

	/*
	* Check netinfo for ipv4 parameters and add them to the fspec iff the
	* fspec has no existing value.
	*/
	static void
	extract_netinfo_args(struct boot_fspec_t *result)
	{
	struct bootp_packet *packet;

	/* Check to see if we can get the [scyg]iaddr fields from netinfo */
	packet = prom_get_netinfo();
	if (!packet)
	return;

	DEBUG_F("We have a boot packet\n");
	DEBUG_F(" siaddr = <%x>\n", packet->siaddr);
	DEBUG_F(" ciaddr = <%x>\n", packet->ciaddr);
	DEBUG_F(" yiaddr = <%x>\n", packet->yiaddr);
	DEBUG_F(" giaddr = <%x>\n", packet->giaddr);

	/* Try to fallback to yiaddr if ciaddr is empty. Broken? */
	if (packet->ciaddr == 0 && packet->yiaddr != 0)
	packet->ciaddr = packet->yiaddr;

	if ((result->siaddr == NULL \|\| *(result->siaddr) == '\x0')
	&& packet->siaddr != 0)
	result->siaddr = ipv4_to_str(packet->siaddr);
	if ((result->ciaddr == NULL \|\| *(result->ciaddr) == '\x0')
	&& packet->ciaddr != 0)
	result->ciaddr = ipv4_to_str(packet->ciaddr);
	if ((result->giaddr == NULL \|\| *(result->giaddr) == '\x0')
	&& packet->giaddr != 0)
	result->giaddr = ipv4_to_str(packet->giaddr);

	extract_vendor_options(packet, result);

	/* FIXME: Yck! if we /still/ do not have a gateway then "cheat" and use
	* the server. This will be okay if the client and server are on
	* the same IP network, if not then lets hope the server does ICMP
	* redirections */
	if (result->giaddr == NULL) {
	result->giaddr = ipv4_to_str(packet->siaddr);
	DEBUG_F("Forcing giaddr to siaddr <%s>\n", result->giaddr);
	}
	}

	/*
	* Extract all the ipv6 arguments from the bootpath provided and fill result
	* Syntax: ipv6,[dhcpv6[=diaddr,]]ciaddr=c_iaddr,giaddr=g_iaddr,siaddr=s_iaddr,
	* filename=file_name,tftp-retries=tftp_retries,blksize=block_size
	* Returns 1 on success, 0 on failure.
	*/
	static int
	extract_ipv6_args(char imagepath, struct boot_fspec_t result)
	{
	char str, tmp;
	int total_len;

	result->is_ipv6 = 1;

	/* Just allocate the max required size */
	total_len = strlen(imagepath) + 1;
	str = malloc(total_len);
	if (!str)
	return 0;

	if ((tmp = strstr(imagepath, "dhcpv6=")) != NULL)
	result->dhcpv6 = scopy(&str, &tmp);

	if ((tmp = strstr(imagepath, "ciaddr=")) != NULL)
	result->ciaddr = scopy(&str, &tmp);

	if ((tmp = strstr(imagepath, "giaddr=")) != NULL)
	result->giaddr = scopy(&str, &tmp);

	if ((tmp = strstr(imagepath, "siaddr=")) != NULL)
	result->siaddr = scopy(&str, &tmp);

	if ((tmp = strstr(imagepath, "filename=")) != NULL)
	result->file = scopy(&str, &tmp);

	if ((tmp = strstr(imagepath, "tftp-retries=")) != NULL)
	result->tftp_retries = scopy(&str, &tmp);

	if ((tmp = strstr(imagepath, "blksize=")) != NULL)
	result->blksize = scopy(&str, &tmp);

	return 1;
	}

	/*
	* Extract all the arguments provided in the imagepath and fill it in result.
	* Returns 1 on success, 0 on failure.
	*/
	static int
	extract_netboot_args(char imagepath, struct boot_fspec_t result)
	{
	int ret;

	DEBUG_F("imagepath = %s\n", imagepath);

	if (!imagepath)
	return 1;

	if (strstr(imagepath, TOK_IPV6))
	ret = extract_ipv6_args(imagepath, result);
	else
	ret = extract_ipv4_args(imagepath, result);
	extract_netinfo_args(result);

	DEBUG_F("ipv6 = <%d>\n", result->is_ipv6);
	DEBUG_F("siaddr = <%s>\n", result->siaddr);
	DEBUG_F("file = <%s>\n", result->file);
	DEBUG_F("ciaddr = <%s>\n", result->ciaddr);
	DEBUG_F("giaddr = <%s>\n", result->giaddr);
	DEBUG_F("bootp_retries = <%s>\n", result->bootp_retries);
	DEBUG_F("tftp_retries = <%s>\n", result->tftp_retries);
	DEBUG_F("addl_params = <%s>\n", result->addl_params);
	DEBUG_F("dhcpv6 = <%s>\n", result->dhcpv6);
	DEBUG_F("blksize = <%s>\n", result->blksize);

	return ret;
	}

	static char netdev_path_to_dev(const char path)
	{
	char dev, tmp;
	size_t len;

	DEBUG_F("path = %s\n", path);

	if (!path)
	return NULL;

	tmp = strchr(path, ':');
	if (!tmp)
	return strdup(path);
	tmp++;

	len = tmp - path + 1;

	dev = malloc(len);
	if (dev) {
	strncpy(dev, path, len);
	dev[len - 1] = '\0';
	}
	return dev;
	}

	/* This function follows the device path in the devtree and separates
	the device name, partition number, and other datas (mostly file name)
	the string passed in parameters is changed since 0 are put in place
	of some separators to terminate the various strings.

	when a default device is supplied imagepath will be assumed to be a
	plain filename unless it contains a : otherwise if defaultdev is
	NULL imagepath will be assumed to be a device path.

	returns 1 on success 0 on failure.

	Supported examples:
	- /pci@80000000/pci-bridge@d/ADPT,2930CU@2/@1:4
	- /pci@80000000/pci-bridge@d/ADPT,2930CU@2/@1:4,/boot/vmlinux
	- hd:3,/boot/vmlinux
	- enet:10.0.0.1,/tftpboot/vmlinux
	- enet:,/tftpboot/vmlinux
	- enet:bootp
	- enet:0
	- arguments for obp-tftp open as specified in section 4.1 of
	http://playground.sun.com/1275/practice/obp-tftp/tftp1_0.pdf
	[bootp,]siaddr,filename,ciaddr,giaddr,bootp-retries,tftp-retries
	ex: enet:bootp,10.0.0.11,bootme,10.0.0.12,10.0.0.1,5,5
	Supported only if defdevice == NULL
	- disc
	- any other device path lacking a :
	Unsupported examples:
	- hd:2,\\:tbxi <- no filename will be detected due to the extra :
	- enet:192.168.2.1,bootme,c-iaddr,g-iaddr,subnet-mask,bootp-retries,tftp-retries */

	int
	parse_device_path(char imagepath, char defdevice, int defpart,
	char deffile, struct boot_fspec_t result)
	{
	char *ptr;
	char *ipath = NULL;
	char *defdev = NULL;
	int device_kind = -1;

	DEBUG_F("imagepath = %s; defdevice %s; defpart %d, deffile %s\n",
	imagepath, defdevice, defpart, deffile);

	result->dev = NULL;
	result->part = -1;
	result->file = NULL;

	if (!imagepath)
	return 0;

	/*
	* Do preliminary checking for an iscsi device; it may appear as
	* pure a network device (device_type == "network") if this is
	* ISWI. This is the case on IBM systems doing an iscsi OFW
	* boot.
	*/
	if (strstr(imagepath, TOK_ISCSI)) {
	/*
	* get the virtual device information from the
	* "nas-bootdevice" property.
	*/
	if (prom_get_chosen("nas-bootdevice", bootdevice, BOOTDEVSZ)) {
	DEBUG_F("reset boot-device to"
	" /chosen/nas-bootdevice = %s\n", bootdevice);
	device_kind = FILE_DEVICE_ISCSI;
	ipath = strdup(bootdevice);
	if (!ipath)
	return 0;
	}
	else
	return 0;
	}
	else if (!(ipath = strdup(imagepath)))
	return 0;

	if (defdevice) {
	defdev = strdup(defdevice);
	device_kind = prom_get_devtype(defdev);
	} else if (device_kind == -1)
	device_kind = prom_get_devtype(ipath);

	/*
	* When an iscsi iqn is present, it may have embedded colons, so
	* don't parse off anything.
	*/
	if (device_kind != FILE_DEVICE_NET &&
	device_kind != FILE_DEVICE_ISCSI &&
	strchr(defdev, ':') != NULL) {
	if ((ptr = strrchr(defdev, ':')) != NULL)
	ptr = 0; / remove trailing : from defdevice if necessary */
	}

	/* This will not properly handle an obp-tftp argument list
	* with elements after the filename; that is handled below.
	*/
	if (device_kind != FILE_DEVICE_NET &&
	device_kind != FILE_DEVICE_ISCSI &&
	strchr(ipath, ':') != NULL) {
	if ((ptr = strrchr(ipath, ',')) != NULL) {
	char *colon = strrchr(ipath, ':');
	/* If a ':' occurs after a ',', then we assume that there is
	no filename */
	if (!colon \|\| colon < ptr) {
	result->file = strdup(ptr+1);
	/* Trim the filename off */
	*ptr = 0;
	}
	}
	}

	if (device_kind == FILE_DEVICE_NET) {
	if (strchr(ipath, ':')) {
	if (extract_netboot_args(ipath, result) == 0)
	return 0;
	} else {
	/* If we didn't get a ':' then look only in netinfo */
	extract_netinfo_args(result);
	result->file = strdup(ipath);
	}

	if (!defdev)
	result->dev = netdev_path_to_dev(ipath);
	} else if (device_kind != FILE_DEVICE_ISCSI &&
	(ptr = strrchr(ipath, ':')) != NULL) {
	*ptr = 0;
	result->dev = strdup(ipath);
	if (*(ptr+1))
	result->part = simple_strtol(ptr+1, NULL, 10);
	} else if (!defdev) {
	result->dev = strdup(ipath);
	} else if (strlen(ipath)) {
	result->file = strdup(ipath);
	} else {
	free(defdev);
	return 0;
	}

	if (!result->dev && defdev)
	result->dev = strdup(defdev);

	if (result->part < 0)
	result->part = defpart;

	if (!result->file)
	result->file = strdup(deffile);

	free(ipath);
	if (defdev)
	free(defdev);
	return 1;
	}


	static int
	file_block_open( struct boot_file_t* file,
	struct boot_fspec_t* fspec,
	int partition)
	{
	struct partition_t* parts;
	struct partition_t* p;
	struct partition_t* found;

	parts = partitions_lookup(fspec->dev);
	found = NULL;

	#if DEBUG
	if (parts)
	prom_printf("partitions:\n");
	else
	prom_printf("no partitions found.\n");
	#endif
	for (p = parts; p && !found; p=p->next) {
	DEBUG_F("number: %02d, start: 0x%08lx, length: 0x%08lx\n",
	p->part_number, p->part_start, p->part_size );
	if (partition == -1) {
	file->fs = fs_open( file, p, fspec );
	if (file->fs == NULL \|\| fserrorno != FILE_ERR_OK)
	continue;
	else {
	partition = p->part_number;
	goto done;
	}
	}
	if ((partition >= 0) && (partition == p->part_number))
	found = p;
	#if DEBUG
	if (found)
	prom_printf(" (match)\n");
	#endif
	}

	/* Note: we don't skip when found is NULL since we can, in some
	* cases, let OF figure out a default partition.
	*/
	DEBUG_F( "Using OF defaults.. (found = %p)\n", found );
	file->fs = fs_open( file, found, fspec );

	done:
	if (parts)
	partitions_free(parts);

	return fserrorno;
	}

	static int
	file_net_open(struct boot_file_t* file, struct boot_fspec_t *fspec)
	{
	file->fs = fs_of_netboot;
	return fs_of_netboot->open(file, NULL, fspec);
	}

	static int
	default_read( struct boot_file_t* file,
	unsigned int size,
	void* buffer)
	{
	prom_printf("WARNING ! default_read called !\n");
	return FILE_ERR_EOF;
	}

	static int
	default_seek( struct boot_file_t* file,
	unsigned int newpos)
	{
	prom_printf("WARNING ! default_seek called !\n");
	return FILE_ERR_EOF;
	}

	static int
	default_close( struct boot_file_t* file)
	{
	prom_printf("WARNING ! default_close called !\n");
	return FILE_ERR_OK;
	}

	static struct fs_t fs_default =
	{
	"defaults",
	NULL,
	default_read,
	default_seek,
	default_close
	};


	int open_file(struct boot_fspec_t* spec, struct boot_file_t* file)
	{
	int result;

	memset(file, 0, sizeof(struct boot_file_t*));
	file->fs = &fs_default;

	DEBUG_F("dev_path = %s\nfile_name = %s\npartition = %d\n",
	spec->dev, spec->file, spec->part);

	result = prom_get_devtype(spec->dev);
	if (result > 0)
	file->device_kind = result;
	else
	return result;

	switch(file->device_kind) {
	case FILE_DEVICE_BLOCK:
	DEBUG_F("device is a block device\n");
	return file_block_open(file, spec, spec->part);
	case FILE_DEVICE_ISCSI:
	DEBUG_F("device is a iSCSI device\n");
	return file_block_open(file, spec, spec->part);
	case FILE_DEVICE_NET:
	DEBUG_F("device is a network device\n");
	return file_net_open(file, spec);
	}
	return 0;
	}

	/*
	* Local variables:
	* c-file-style: "k&r"
	* c-basic-offset: 5
	* End:
	*/