grub-core/commands/legacycfg.c

/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 2000, 2001, 2010  Free Software Foundation, Inc.
 *
 *  GRUB 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 3 of the License, or
 *  (at your option) any later version.
 *
 *  GRUB 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 GRUB.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <grub/types.h>
#include <grub/misc.h>
#include <grub/command.h>
#include <grub/mm.h>
#include <grub/err.h>
#include <grub/dl.h>
#include <grub/file.h>
#include <grub/normal.h>
#include <grub/script_sh.h>
#include <grub/i18n.h>
#include <grub/term.h>
#include <grub/legacy_parse.h>
#include <grub/crypto.h>
#include <grub/auth.h>
#include <grub/disk.h>
#include <grub/partition.h>

GRUB_MOD_LICENSE ("GPLv3+");

static grub_err_t
legacy_file (const char *filename)
{
  grub_file_t file;
  char *entryname = NULL, *entrysrc = NULL;
  grub_menu_t menu;
  char *suffix = grub_strdup ("");

  auto grub_err_t getline (char **line, int cont);
  grub_err_t getline (char **line,
              int cont __attribute__ ((unused)))
  {
    *line = 0;
    return GRUB_ERR_NONE;
  }

  if (!suffix)
    return grub_errno;

  file = grub_file_open (filename);
  if (! file)
    return grub_errno;

  menu = grub_env_get_menu ();
  if (! menu)
    {
      menu = grub_zalloc (sizeof (*menu));
      if (! menu)
    return grub_errno;

      grub_env_set_menu (menu);
    }

  while (1)
    {
      char *buf = grub_file_getline (file);
      char *parsed = NULL;

      if (!buf && grub_errno)
    {
      grub_file_close (file);
      return grub_errno;
    }

      if (!buf)
    break;

      {
    char *oldname = NULL;
    char *newsuffix;
    char *ptr;

    for (ptr = buf; *ptr && grub_isspace (*ptr); ptr++);

    oldname = entryname;
    parsed = grub_legacy_parse (ptr, &entryname, &newsuffix);
    grub_free (buf);
    buf = NULL;
    if (newsuffix)
      {
        char *t;

        t = suffix;
        suffix = grub_realloc (suffix, grub_strlen (suffix)
                   + grub_strlen (newsuffix) + 1);
        if (!suffix)
          {
        grub_free (t);
        grub_free (entrysrc);
        grub_free (parsed);
        grub_free (newsuffix);
        grub_free (suffix);
        return grub_errno;
          }
        grub_memcpy (suffix + grub_strlen (suffix), newsuffix,
             grub_strlen (newsuffix) + 1);
        grub_free (newsuffix);
        newsuffix = NULL;
      }
    if (oldname != entryname && oldname)
      {
        const char **args = grub_malloc (sizeof (args[0]));
        if (!args)
          {
        grub_file_close (file);
        return grub_errno;
          }
        args[0] = oldname;
        grub_normal_add_menu_entry (1, args, NULL, NULL, NULL, NULL,
                    entrysrc, 0);
        grub_free (args);
        entrysrc[0] = 0;
        grub_free (oldname);
      }
      }

      if (parsed && !entryname)
    {
      grub_normal_parse_line (parsed, getline);
      grub_print_error ();
      grub_free (parsed);
      parsed = NULL;
    }
      else if (parsed)
    {
      if (!entrysrc)
        entrysrc = parsed;
      else
        {
          char *t;

          t = entrysrc;
          entrysrc = grub_realloc (entrysrc, grub_strlen (entrysrc)
                       + grub_strlen (parsed) + 1);
          if (!entrysrc)
        {
          grub_free (t);
          grub_free (parsed);
          grub_free (suffix);
          return grub_errno;
        }
          grub_memcpy (entrysrc + grub_strlen (entrysrc), parsed,
               grub_strlen (parsed) + 1);
          grub_free (parsed);
          parsed = NULL;
        }
    }
    }
  grub_file_close (file);

  if (entryname)
    {
      const char **args = grub_malloc (sizeof (args[0]));
      if (!args)
    {
      grub_file_close (file);
      return grub_errno;
    }
      args[0] = entryname;
      grub_normal_add_menu_entry (1, args, NULL, NULL, NULL, NULL, entrysrc, 0);
      grub_free (args);
    }

  grub_normal_parse_line (suffix, getline);
  grub_print_error ();
  grub_free (suffix);
  grub_free (entrysrc);

  return GRUB_ERR_NONE;
}

static grub_err_t
grub_cmd_legacy_source (struct grub_command *cmd,
            int argc, char **args)
{
  int new_env, extractor;
  grub_err_t ret;

  if (argc != 1)
    return grub_error (GRUB_ERR_BAD_ARGUMENT, "file name required");

  extractor = (cmd->name[0] == 'e');
  new_env = (cmd->name[extractor ? (sizeof ("extract_legacy_entries_") - 1)
               : (sizeof ("legacy_") - 1)] == 'c');

  if (new_env)
    grub_cls ();

  if (new_env && !extractor)
    grub_env_context_open ();
  if (extractor)
    grub_env_extractor_open (!new_env);

  ret = legacy_file (args[0]);

  if (new_env)
    {
      grub_menu_t menu;
      menu = grub_env_get_menu ();
      if (menu && menu->size)
    grub_show_menu (menu, 1, 0);
      if (!extractor)
    grub_env_context_close ();
    }
  if (extractor)
    grub_env_extractor_close (!new_env);

  return ret;
}

static enum
  {
    GUESS_IT, LINUX, MULTIBOOT, KFREEBSD, KNETBSD, KOPENBSD
  } kernel_type;

static grub_err_t
grub_cmd_legacy_kernel (struct grub_command *mycmd __attribute__ ((unused)),
            int argc, char **args)
{
  int i;
#ifdef TODO
  int no_mem_option = 0;
#endif
  struct grub_command *cmd;
  char **cutargs;
  int cutargc;

  for (i = 0; i < 2; i++)
    {
      /* FIXME: really support this.  */
      if (argc >= 1 && grub_strcmp (args[0], "--no-mem-option") == 0)
    {
#ifdef TODO
      no_mem_option = 1;
#endif
      argc--;
      args++;
      continue;
    }

      /* linux16 handles both zImages and bzImages.   */
      if (argc >= 1 && (grub_strcmp (args[0], "--type=linux") == 0
            || grub_strcmp (args[0], "--type=biglinux") == 0))
    {
      kernel_type = LINUX;
      argc--;
      args++;
      continue;
    }

      if (argc >= 1 && grub_strcmp (args[0], "--type=multiboot") == 0)
    {
      kernel_type = MULTIBOOT;
      argc--;
      args++;
      continue;
    }

      if (argc >= 1 && grub_strcmp (args[0], "--type=freebsd") == 0)
    {
      kernel_type = KFREEBSD;
      argc--;
      args++;
      continue;
    }

      if (argc >= 1 && grub_strcmp (args[0], "--type=openbsd") == 0)
    {
      kernel_type = KOPENBSD;
      argc--;
      args++;
      continue;
    }

      if (argc >= 1 && grub_strcmp (args[0], "--type=netbsd") == 0)
    {
      kernel_type = KNETBSD;
      argc--;
      args++;
      continue;
    }
    }

  if (argc < 2)
    return grub_error (GRUB_ERR_BAD_ARGUMENT, "filename required");

  cutargs = grub_malloc (sizeof (cutargs[0]) * (argc - 1));
  cutargc = argc - 1;
  grub_memcpy (cutargs + 1, args + 2, sizeof (cutargs[0]) * (argc - 2));
  cutargs[0] = args[0];

  do
    {
      /* First try Linux.  */
      if (kernel_type == GUESS_IT || kernel_type == LINUX)
    {
      cmd = grub_command_find ("linux16");
      if (cmd)
        {
          if (!(cmd->func) (cmd, cutargc, cutargs))
        {
          kernel_type = LINUX;
          return GRUB_ERR_NONE;
        }
        }
      grub_errno = GRUB_ERR_NONE;
    }

      /* Then multiboot.  */
      if (kernel_type == GUESS_IT || kernel_type == MULTIBOOT)
    {
      cmd = grub_command_find ("multiboot");
      if (cmd)
        {
          if (!(cmd->func) (cmd, argc, args))
        {
          kernel_type = MULTIBOOT;
          return GRUB_ERR_NONE;
        }
        }
      grub_errno = GRUB_ERR_NONE;
    }

      {
    int bsd_device = -1;
    int bsd_slice = -1;
    int bsd_part = -1;
    {
      grub_device_t dev;
      const char *hdbiasstr;
      int hdbias = 0;
      hdbiasstr = grub_env_get ("legacy_hdbias");
      if (hdbiasstr)
        {
          hdbias = grub_strtoul (hdbiasstr, 0, 0);
          grub_errno = GRUB_ERR_NONE;
        }
      dev = grub_device_open (0);
      if (dev && dev->disk
          && dev->disk->dev->id == GRUB_DISK_DEVICE_BIOSDISK_ID
          && dev->disk->dev->id >= 0x80 && dev->disk->dev->id <= 0x90)
        {
          struct grub_partition *part = dev->disk->partition;
          bsd_device = dev->disk->id - 0x80 - hdbias;
          if (part && (grub_strcmp (part->partmap->name, "netbsd") == 0
               || grub_strcmp (part->partmap->name, "openbsd") == 0
               || grub_strcmp (part->partmap->name, "bsd") == 0))
        {
          bsd_part = part->number;
          part = part->parent;
        }
          if (part && grub_strcmp (part->partmap->name, "msdos") == 0)
        bsd_slice = part->number;
        }
    }

    /* k*BSD didn't really work well with grub-legacy.  */
    if (kernel_type == GUESS_IT || kernel_type == KFREEBSD)
      {
        char buf[sizeof("adXXXXXXXXXXXXsXXXXXXXXXXXXYYY")];
        if (bsd_device != -1)
          {
        if (bsd_slice != -1 && bsd_part != -1)
          grub_snprintf(buf, sizeof(buf), "ad%ds%d%c", bsd_device,
                bsd_slice, 'a' + bsd_part);
        else if (bsd_slice != -1)
          grub_snprintf(buf, sizeof(buf), "ad%ds%d", bsd_device,
                bsd_slice);
        else
          grub_snprintf(buf, sizeof(buf), "ad%d", bsd_device);
        grub_env_set ("kFreeBSD.vfs.root.mountfrom", buf);
          }
        else
          grub_env_unset ("kFreeBSD.vfs.root.mountfrom");
        cmd = grub_command_find ("kfreebsd");
        if (cmd)
          {
        if (!(cmd->func) (cmd, cutargc, cutargs))
          {
            kernel_type = KFREEBSD;
            return GRUB_ERR_NONE;
          }
          }
        grub_errno = GRUB_ERR_NONE;
      }
    {
      char **bsdargs;
      int bsdargc;
      char bsddevname[sizeof ("wdXXXXXXXXXXXXY")];
      if (bsd_device == -1)
        {
          bsdargs = cutargs;
          bsdargc = cutargc;
        }
      else
        {
          bsdargc = cutargc + 2;
          bsdargs = grub_malloc (sizeof (bsdargs[0]) * bsdargc);
          grub_memcpy (bsdargs, args, argc * sizeof (bsdargs[0]));
          bsdargs[argc] = "-r";
          bsdargs[argc + 1] = bsddevname;
          grub_snprintf (bsddevname, sizeof (bsddevname),
                 "wd%d%c", bsd_device,
                 bsd_part != -1 ? bsd_part + 'a' : 'c');
        }
      if (kernel_type == GUESS_IT || kernel_type == KNETBSD)
        {
          cmd = grub_command_find ("knetbsd");
          if (cmd)
        {
          if (!(cmd->func) (cmd, bsdargc, bsdargs))
            {
              kernel_type = KNETBSD;
              return GRUB_ERR_NONE;
            }
        }
          grub_errno = GRUB_ERR_NONE;
        }
      if (kernel_type == GUESS_IT || kernel_type == KOPENBSD)
        {
          cmd = grub_command_find ("kopenbsd");
          if (cmd)
        {
          if (!(cmd->func) (cmd, bsdargc, bsdargs))
            {
              kernel_type = KOPENBSD;
              return GRUB_ERR_NONE;
            }
        }
          grub_errno = GRUB_ERR_NONE;
        }
      if (bsdargs != cutargs)
        grub_free (bsdargs);
    }
      }
    }
  while (0);

  return grub_error (GRUB_ERR_BAD_OS, "couldn't load file %s\n",
             args[0]);
}

static grub_err_t
grub_cmd_legacy_initrd (struct grub_command *mycmd __attribute__ ((unused)),
            int argc, char **args)
{
  struct grub_command *cmd;

  if (kernel_type == LINUX)
    {
      cmd = grub_command_find ("initrd16");
      if (!cmd)
    return grub_error (GRUB_ERR_BAD_ARGUMENT, "command initrd16 not found");

      return cmd->func (cmd, argc, args);
    }
  if (kernel_type == MULTIBOOT)
    {
      cmd = grub_command_find ("module");
      if (!cmd)
    return grub_error (GRUB_ERR_BAD_ARGUMENT, "command module not found");

      return cmd->func (cmd, argc, args);
    }

  return grub_error (GRUB_ERR_BAD_ARGUMENT,
             "no kernel with module support is loaded in legacy way");
}

static grub_err_t
grub_cmd_legacy_initrdnounzip (struct grub_command *mycmd __attribute__ ((unused)),
                   int argc, char **args)
{
  struct grub_command *cmd;

  if (kernel_type == LINUX)
    {
      cmd = grub_command_find ("initrd16");
      if (!cmd)
    return grub_error (GRUB_ERR_BAD_ARGUMENT, "command initrd16 not found");

      return cmd->func (cmd, argc, args);
    }
  if (kernel_type == MULTIBOOT)
    {
      char **newargs;
      grub_err_t err;
      newargs = grub_malloc ((argc + 1) * sizeof (newargs[0]));
      if (!newargs)
    return grub_errno;
      grub_memcpy (newargs + 1, args, argc * sizeof (newargs[0]));
      newargs[0] = "--nounzip";
      cmd = grub_command_find ("module");
      if (!cmd)
    return grub_error (GRUB_ERR_BAD_ARGUMENT, "command module not found");

      err = cmd->func (cmd, argc + 1, newargs);
      grub_free (newargs);
      return err;
    }

  return grub_error (GRUB_ERR_BAD_ARGUMENT,
             "no kernel with module support is loaded in legacy way");
}

static grub_err_t
check_password_deny (const char *user __attribute__ ((unused)),
             const char *entered  __attribute__ ((unused)),
             void *password __attribute__ ((unused)))
{
  return GRUB_ACCESS_DENIED;
}

#define MD5_HASHLEN 16

struct legacy_md5_password
{
  grub_uint8_t *salt;
  int saltlen;
  grub_uint8_t hash[MD5_HASHLEN];
};

static int
check_password_md5_real (const char *entered,
             struct legacy_md5_password *pw)
{
  int enteredlen = grub_strlen (entered);
  unsigned char alt_result[MD5_HASHLEN];
  unsigned char *digest;
  grub_uint8_t ctx[GRUB_MD_MD5->contextsize];
  int i;

  GRUB_MD_MD5->init (ctx);
  GRUB_MD_MD5->write (ctx, entered, enteredlen);
  GRUB_MD_MD5->write (ctx, pw->salt + 3, pw->saltlen - 3);
  GRUB_MD_MD5->write (ctx, entered, enteredlen);
  digest = GRUB_MD_MD5->read (ctx);
  GRUB_MD_MD5->final (ctx);
  memcpy (alt_result, digest, MD5_HASHLEN);

  GRUB_MD_MD5->init (ctx);
  GRUB_MD_MD5->write (ctx, entered, enteredlen);
  GRUB_MD_MD5->write (ctx, pw->salt, pw->saltlen); /* include the $1$ header */
  for (i = enteredlen; i > 16; i -= 16)
    GRUB_MD_MD5->write (ctx, alt_result, 16);
  GRUB_MD_MD5->write (ctx, alt_result, i);

  for (i = enteredlen; i > 0; i >>= 1)
    GRUB_MD_MD5->write (ctx, entered + ((i & 1) ? enteredlen : 0), 1);
  digest = GRUB_MD_MD5->read (ctx);
  GRUB_MD_MD5->final (ctx);

  for (i = 0; i < 1000; i++)
    {
      memcpy (alt_result, digest, 16);

      GRUB_MD_MD5->init (ctx);
      if ((i & 1) != 0)
    GRUB_MD_MD5->write (ctx, entered, enteredlen);
      else
    GRUB_MD_MD5->write (ctx, alt_result, 16);

      if (i % 3 != 0)
    GRUB_MD_MD5->write (ctx, pw->salt + 3, pw->saltlen - 3);

      if (i % 7 != 0)
    GRUB_MD_MD5->write (ctx, entered, enteredlen);

      if ((i & 1) != 0)
    GRUB_MD_MD5->write (ctx, alt_result, 16);
      else
    GRUB_MD_MD5->write (ctx, entered, enteredlen);
      digest = GRUB_MD_MD5->read (ctx);
      GRUB_MD_MD5->final (ctx);
    }

  return (grub_crypto_memcmp (digest, pw->hash, MD5_HASHLEN) == 0);
}

static grub_err_t
check_password_md5 (const char *user,
            const char *entered,
            void *password)
{
  if (!check_password_md5_real (entered, password))
    return GRUB_ACCESS_DENIED;

  grub_auth_authenticate (user);

  return GRUB_ERR_NONE;
}

static inline int
ib64t (char c)
{
  if (c == '.')
    return 0;
  if (c == '/')
    return 1;
  if (c >= '0' && c <= '9')
    return c - '0' + 2;
  if (c >= 'A' && c <= 'Z')
    return c - 'A' + 12;
  if (c >= 'a' && c <= 'z')
    return c - 'a' + 38;
  return -1;
}

static struct legacy_md5_password *
parse_legacy_md5 (int argc, char **args)
{
  const char *salt, *saltend;
  struct legacy_md5_password *pw = NULL;
  int i;
  const char *p;

  if (grub_memcmp (args[0], "--md5", sizeof ("--md5")) != 0)
    goto fail;
  if (argc == 1)
    goto fail;
  if (grub_strlen(args[1]) <= 3)
    goto fail;
  salt = args[1];
  saltend = grub_strchr (salt + 3, '$');
  if (!saltend)
    goto fail;
  pw = grub_malloc (sizeof (*pw));
  if (!pw)
    goto fail;

  p = saltend + 1;
  for (i = 0; i < 5; i++)
    {
      int n;
      grub_uint32_t w = 0;

      for (n = 0; n < 4; n++)
    {
      int ww = ib64t(*p++);
      if (ww == -1)
        goto fail;
      w |= ww << (n * 6);
    }
      pw->hash[i == 4 ? 5 : 12+i] = w & 0xff;
      pw->hash[6+i] = (w >> 8) & 0xff;
      pw->hash[i] = (w >> 16) & 0xff;
    }
  {
    int n;
    grub_uint32_t w = 0;
    for (n = 0; n < 2; n++)
      {
    int ww = ib64t(*p++);
    if (ww == -1)
      goto fail;
    w |= ww << (6 * n);
      }
    if (w >= 0x100)
      goto fail;
    pw->hash[11] = w;
  }

  pw->saltlen = saltend - salt;
  pw->salt = (grub_uint8_t *) grub_strndup (salt, pw->saltlen);
  if (!pw->salt)
    goto fail;

  return pw;

 fail:
  grub_free (pw);
  return NULL;
}

static grub_err_t
grub_cmd_legacy_password (struct grub_command *mycmd __attribute__ ((unused)),
              int argc, char **args)
{
  struct legacy_md5_password *pw = NULL;

  if (argc == 0)
    return grub_error (GRUB_ERR_BAD_ARGUMENT, "arguments expected");
  if (args[0][0] != '-' || args[0][1] != '-')
    return grub_normal_set_password ("legacy", args[0]);

  pw = parse_legacy_md5 (argc, args);

  if (pw)
    return grub_auth_register_authentication ("legacy", check_password_md5, pw);
  else
    /* This is to imitate minor difference between grub-legacy in GRUB2.
       If 2 password commands are executed in a row and second one fails
       on GRUB2 the password of first one is used, whereas in grub-legacy
       authenthication is denied. In case of no password command was executed
       early both versions deny any access.  */
    return grub_auth_register_authentication ("legacy", check_password_deny,
                          NULL);
}

static grub_err_t
grub_cmd_legacy_check_password (struct grub_command *mycmd __attribute__ ((unused)),
                int argc, char **args)
{
  struct legacy_md5_password *pw = NULL;
  char entered[GRUB_AUTH_MAX_PASSLEN];

  if (argc == 0)
    return grub_error (GRUB_ERR_BAD_ARGUMENT, "arguments expected");
  grub_puts_ (N_("Enter password: "));
  if (!grub_password_get (entered, GRUB_AUTH_MAX_PASSLEN))
    return GRUB_ACCESS_DENIED;

  if (args[0][0] != '-' || args[0][1] != '-')
    {
      char correct[GRUB_AUTH_MAX_PASSLEN];

      grub_memset (correct, 0, sizeof (correct));
      grub_strncpy (correct, args[0], sizeof (correct));

      if (grub_crypto_memcmp (entered, correct, GRUB_AUTH_MAX_PASSLEN) != 0)
    return GRUB_ACCESS_DENIED;
      return GRUB_ERR_NONE;
    }

  pw = parse_legacy_md5 (argc, args);

  if (!pw)
    return GRUB_ACCESS_DENIED;

  if (!check_password_md5_real (entered, pw))
    return GRUB_ACCESS_DENIED;

  return GRUB_ERR_NONE;
}

static grub_command_t cmd_source, cmd_configfile;
static grub_command_t cmd_source_extract, cmd_configfile_extract;
static grub_command_t cmd_kernel, cmd_initrd, cmd_initrdnounzip;
static grub_command_t cmd_password, cmd_check_password;

GRUB_MOD_INIT(legacycfg)
{
  cmd_source
    = grub_register_command ("legacy_source",
                 grub_cmd_legacy_source,
                 N_("FILE"),
                 N_("Parse legacy config in same context"));
  cmd_configfile
    = grub_register_command ("legacy_configfile",
                 grub_cmd_legacy_source,
                 N_("FILE"),
                 N_("Parse legacy config in new context"));
  cmd_source_extract
    = grub_register_command ("extract_legacy_entries_source",
                 grub_cmd_legacy_source,
                 N_("FILE"),
                 N_("Parse legacy config in same context taking only menu entries"));
  cmd_configfile_extract
    = grub_register_command ("extract_legacy_entries_configfile",
                 grub_cmd_legacy_source,
                 N_("FILE"),
                 N_("Parse legacy config in new context taking only menu entries"));

  cmd_kernel = grub_register_command ("legacy_kernel",
                      grub_cmd_legacy_kernel,
                      N_("[--no-mem-option] [--type=TYPE] FILE [ARG ...]"),
                      N_("Simulate grub-legacy kernel command"));

  cmd_initrd = grub_register_command ("legacy_initrd",
                      grub_cmd_legacy_initrd,
                      N_("FILE [ARG ...]"),
                      N_("Simulate grub-legacy initrd command"));
  cmd_initrdnounzip = grub_register_command ("legacy_initrd_nounzip",
                         grub_cmd_legacy_initrdnounzip,
                         N_("FILE [ARG ...]"),
                         N_("Simulate grub-legacy modulenounzip command"));

  cmd_password = grub_register_command ("legacy_password",
                    grub_cmd_legacy_password,
                    N_("[--md5] PASSWD [FILE]"),
                    N_("Simulate grub-legacy password command"));

  cmd_check_password = grub_register_command ("legacy_check_password",
                          grub_cmd_legacy_check_password,
                          N_("[--md5] PASSWD [FILE]"),
                          N_("Simulate grub-legacy password command in menuentry mode"));

}

GRUB_MOD_FINI(legacycfg)
{
  grub_unregister_command (cmd_source);
  grub_unregister_command (cmd_configfile);
  grub_unregister_command (cmd_source_extract);
  grub_unregister_command (cmd_configfile_extract);

  grub_unregister_command (cmd_kernel);
  grub_unregister_command (cmd_initrd);
  grub_unregister_command (cmd_initrdnounzip);

  grub_unregister_command (cmd_password);
  grub_unregister_command (cmd_check_password);
}