From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001

From: Peter Jones <pjones@redhat.com>

Date: Fri, 9 Dec 2016 15:40:58 -0500

Subject: [PATCH] Add blscfg command support to parse BootLoaderSpec config

 fragments

The BootLoaderSpec (BLS) defines a scheme where different bootloaders can

share a format for boot items and a configuration directory that accepts

these common configurations as drop-in files.

GRUB2 already has a blscfg modle that can parse the config snippets using

the bls_import command, change it to blscfg and improve the BLS support.

---

 grub-core/Makefile.core.def  |   4 +-

 grub-core/commands/blscfg.c  | 796 ++++++++++++++++++++++++++++++++++++++++---

 grub-core/commands/loadenv.c |  77 +----

 grub-core/commands/loadenv.h |  93 +++++

 include/grub/compiler.h      |   2 +

 5 files changed, 840 insertions(+), 132 deletions(-)

 create mode 100644 grub-core/commands/loadenv.h

diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def

index 27563743b..96ccb4021 100644

--- a/grub-core/Makefile.core.def

+++ b/grub-core/Makefile.core.def

@@ -129,6 +129,7 @@ kernel = {

   common = kern/rescue_parser.c;

   common = kern/rescue_reader.c;

   common = kern/term.c;

+  common = kern/qsort.c;

   noemu = kern/compiler-rt.c;

   noemu = kern/mm.c;

@@ -774,8 +775,7 @@ module = {

 module = {

   name = blscfg;

   common = commands/blscfg.c;

-  enable = i386_efi;

-  enable = x86_64_efi;

+  enable = efi;

   enable = i386_pc;

 };

diff --git a/grub-core/commands/blscfg.c b/grub-core/commands/blscfg.c

index 4274aca5a..86796c8cd 100644

--- a/grub-core/commands/blscfg.c

+++ b/grub-core/commands/blscfg.c

@@ -30,32 +30,405 @@

 #include <grub/env.h>

 #include <grub/file.h>

 #include <grub/normal.h>

+#include <grub/lib/envblk.h>

 GRUB_MOD_LICENSE ("GPLv3+");

+#include "loadenv.h"

+

+#define GRUB_BLS_CONFIG_PATH "/loader/entries/"

+#define GRUB_BOOT_DEVICE "($root)"

 #ifdef GRUB_MACHINE_EFI

 #define GRUB_LINUX_CMD "linuxefi"

 #define GRUB_INITRD_CMD "initrdefi"

-#define GRUB_BLS_CONFIG_PATH "/EFI/fedora/loader/entries/"

-#define GRUB_BOOT_DEVICE "($boot)"

 #else

 #define GRUB_LINUX_CMD "linux"

 #define GRUB_INITRD_CMD "initrd"

-#define GRUB_BLS_CONFIG_PATH "/loader/entries/"

-#define GRUB_BOOT_DEVICE "($root)"

 #endif

-static int parse_entry (

+#define grub_free(x) ({grub_dprintf("blscfg", "%s freeing %p\n", __func__, x); grub_free(x); })

+

+struct keyval

+{

+  const char *key;

+  char *val;

+};

+

+struct bls_entry

+{

+  struct keyval **keyvals;

+  int nkeyvals;

+};

+

+static struct bls_entry **entries;

+static int nentries;

+

+static struct bls_entry *bls_new_entry(void)

+{

+  struct bls_entry **new_entries;

+  struct bls_entry *entry;

+  int new_n = nentries + 1;

+

+  new_entries = grub_realloc (entries,  new_n * sizeof (struct bls_entry *));

+  if (!new_entries)

+    {

+      grub_error (GRUB_ERR_OUT_OF_MEMORY,

+		  "couldn't find space for BLS entry list");

+      return NULL;

+    }

+

+  entries = new_entries;

+

+  entry = grub_malloc (sizeof (*entry));

+  if (!entry)

+    {

+      grub_error (GRUB_ERR_OUT_OF_MEMORY,

+		  "couldn't find space for BLS entry list");

+      return NULL;

+    }

+

+  grub_memset (entry, 0, sizeof (*entry));

+  entries[nentries] = entry;

+

+  nentries = new_n;

+

+  return entry;

+}

+

+static int bls_add_keyval(struct bls_entry *entry, char *key, char *val)

+{

+  char *k, *v;

+  struct keyval **kvs, *kv;

+  int new_n = entry->nkeyvals + 1;

+

+  kvs = grub_realloc (entry->keyvals, new_n * sizeof (struct keyval *));

+  if (!kvs)

+    return grub_error (GRUB_ERR_OUT_OF_MEMORY,

+		       "couldn't find space for BLS entry");

+  entry->keyvals = kvs;

+

+  kv = grub_malloc (sizeof (struct keyval));

+  if (!kv)

+    return grub_error (GRUB_ERR_OUT_OF_MEMORY,

+		       "couldn't find space for BLS entry");

+

+  k = grub_strdup (key);

+  if (!k)

+    {

+      grub_free (kv);

+      return grub_error (GRUB_ERR_OUT_OF_MEMORY,

+			 "couldn't find space for BLS entry");

+    }

+

+  v = grub_strdup (val);

+  if (!v)

+    {

+      grub_free (k);

+      grub_free (kv);

+      return grub_error (GRUB_ERR_OUT_OF_MEMORY,

+			 "couldn't find space for BLS entry");

+    }

+

+  kv->key = k;

+  kv->val = v;

+

+  entry->keyvals[entry->nkeyvals] = kv;

+  grub_dprintf("blscfg", "new keyval at %p:%p:%p\n", entry->keyvals[entry->nkeyvals], k, v);

+  entry->nkeyvals = new_n;

+

+  return 0;

+}

+

+static void bls_free_entry(struct bls_entry *entry)

+{

+  int i;

+

+  grub_dprintf("blscfg", "%s got here\n", __func__);

+  for (i = 0; i < entry->nkeyvals; i++)

+    {

+      struct keyval *kv = entry->keyvals[i];

+      grub_free ((void *)kv->key);

+      grub_free (kv->val);

+      grub_free (kv);

+    }

+

+  grub_free (entry->keyvals);

+  grub_memset (entry, 0, sizeof (*entry));

+  grub_free (entry);

+}

+

+static int keyval_cmp (const void *p0, const void *p1,

+		       void *state UNUSED)

+{

+  const struct keyval *kv0 = *(struct keyval * const *)p0;

+  const struct keyval *kv1 = *(struct keyval * const *)p1;

+  int rc;

+

+  rc = grub_strcmp(kv0->key, kv1->key);

+

+  return rc;

+}

+

+/* Find they value of the key named by keyname.  If there are allowed to be

+ * more than one, pass a pointer to an int set to -1 the first time, and pass

+ * the same pointer through each time after, and it'll return them in sorted

+ * order. */

+static char *bls_get_val(struct bls_entry *entry, const char *keyname, int *last)

+{

+  char *foo = (char *)"";

+  struct keyval *kv = NULL, **kvp, key = {keyname, foo}, *keyp = &ke;;

+

+  /* if we've already found an entry that matches, just iterate */

+  if (last && *last >= 0)

+    {

+      int next = ++last[0];

+

+      if (next == entry->nkeyvals)

+	{

+done:

+	  *last = -1;

+	  return NULL;

+	}

+

+      kv = entry->keyvals[next];

+      if (grub_strcmp (keyname, kv->key))

+	goto done;

+

+      return kv->val;

+    }

+

+  kvp = grub_bsearch(&keyp, &entry->keyvals[0], entry->nkeyvals,

+		    sizeof (struct keyval *), keyval_cmp, NULL);

+  if (kvp)

+    kv = *kvp;

+

+  if (kv)

+    {

+      /* if we've got uninitialized but present state, track back until we find

+       * the first match */

+      if (last)

+	{

+	  grub_dprintf("blscfg", "%s trying to find another entry because last was set\n", __func__);

+	  /* figure out the position of this entry in the array */

+	  int idx;

+	  for (idx = 0 ; idx < entry->nkeyvals; idx++)

+	    if (entry->keyvals[idx] == kv)

+	      break;

+	  *last = idx;

+

+	  while (idx > 0)

+	    {

+	      struct keyval *kvtmp = entry->keyvals[idx-1];

+	      if (idx == 0 || grub_strcmp (keyname, kvtmp->key))

+		{

+		  /* if we're at the start, or if the previous entry doesn't

+		   * match, then we're done */

+		  *last = idx;

+		  break;

+		}

+	      else

+		/* but if it does match, keep going backwards */

+		idx--;

+	    }

+	}

+

+      return kv->val;

+    }

+  return NULL;

+}

+

+#define goto_return(x) ({ ret = (x); goto finish; })

+

+/* compare alpha and numeric segments of two versions */

+/* return 1: a is newer than b */

+/*        0: a and b are the same version */

+/*       -1: b is newer than a */

+static int vercmp(const char * a, const char * b)

+{

+    char oldch1, oldch2;

+    char *abuf, *bbuf;

+    char *str1, *str2;

+    char * one, * two;

+    int rc;

+    int isnum;

+    int ret = 0;

+

+  grub_dprintf("blscfg", "%s got here\n", __func__);

+    if (!grub_strcmp(a, b))

+	    return 0;

+

+    abuf = grub_malloc(grub_strlen(a) + 1);

+    bbuf = grub_malloc(grub_strlen(b) + 1);

+    str1 = abuf;

+    str2 = bbuf;

+    grub_strcpy(str1, a);

+    grub_strcpy(str2, b);

+

+    one = str1;

+    two = str2;

+

+    /* loop through each version segment of str1 and str2 and compare them */

+    while (*one || *two) {

+	while (*one && !grub_isalnum(*one) && *one != '~') one++;

+	while (*two && !grub_isalnum(*two) && *two != '~') two++;

+

+	/* handle the tilde separator, it sorts before everything else */

+	if (*one == '~' || *two == '~') {

+	    if (*one != '~') goto_return (1);

+	    if (*two != '~') goto_return (-1);

+	    one++;

+	    two++;

+	    continue;

+	}

+

+	/* If we ran to the end of either, we are finished with the loop */

+	if (!(*one && *two)) break;

+

+	str1 = one;

+	str2 = two;

+

+	/* grab first completely alpha or completely numeric segment */

+	/* leave one and two pointing to the start of the alpha or numeric */

+	/* segment and walk str1 and str2 to end of segment */

+	if (grub_isdigit(*str1)) {

+	    while (*str1 && grub_isdigit(*str1)) str1++;

+	    while (*str2 && grub_isdigit(*str2)) str2++;

+	    isnum = 1;

+	} else {

+	    while (*str1 && grub_isalpha(*str1)) str1++;

+	    while (*str2 && grub_isalpha(*str2)) str2++;

+	    isnum = 0;

+	}

+

+	/* save character at the end of the alpha or numeric segment */

+	/* so that they can be restored after the comparison */

+	oldch1 = *str1;

+	*str1 = '\0';

+	oldch2 = *str2;

+	*str2 = '\0';

+

+	/* this cannot happen, as we previously tested to make sure that */

+	/* the first string has a non-null segment */

+	if (one == str1) goto_return(-1);	/* arbitrary */

+

+	/* take care of the case where the two version segments are */

+	/* different types: one numeric, the other alpha (i.e. empty) */

+	/* numeric segments are always newer than alpha segments */

+	/* XXX See patch #60884 (and details) from bugzilla #50977. */

+	if (two == str2) goto_return (isnum ? 1 : -1);

+

+	if (isnum) {

+	    grub_size_t onelen, twolen;

+	    /* this used to be done by converting the digit segments */

+	    /* to ints using atoi() - it's changed because long  */

+	    /* digit segments can overflow an int - this should fix that. */

+

+	    /* throw away any leading zeros - it's a number, right? */

+	    while (*one == '0') one++;

+	    while (*two == '0') two++;

+

+	    /* whichever number has more digits wins */

+	    onelen = grub_strlen(one);

+	    twolen = grub_strlen(two);

+	    if (onelen > twolen) goto_return (1);

+	    if (twolen > onelen) goto_return (-1);

+	}

+

+	/* grub_strcmp will return which one is greater - even if the two */

+	/* segments are alpha or if they are numeric.  don't return  */

+	/* if they are equal because there might be more segments to */

+	/* compare */

+	rc = grub_strcmp(one, two);

+	if (rc) goto_return (rc < 1 ? -1 : 1);

+

+	/* restore character that was replaced by null above */

+	*str1 = oldch1;

+	one = str1;

+	*str2 = oldch2;

+	two = str2;

+    }

+

+    /* this catches the case where all numeric and alpha segments have */

+    /* compared identically but the segment sepparating characters were */

+    /* different */

+    if ((!*one) && (!*two)) goto_return (0);

+

+    /* whichever version still has characters left over wins */

+    if (!*one) goto_return (-1); else goto_return (1);

+

+finish:

+    grub_free (abuf);

+    grub_free (bbuf);

+    return ret;

+}

+

+typedef int (*void_cmp_t)(void *, void *);

+

+static int nulcmp(char *s0, char *s1, void_cmp_t cmp)

+{

+  grub_dprintf("blscfg", "%s got here\n", __func__);

+  if (s1 && !s0)

+    return 1;

+  if (s0 && !s1)

+    return -1;

+  if (!s0 && !s1)

+    return 0;

+  if (cmp)

+    return cmp(s0, s1);

+  return grub_strcmp(s0, s1);

+}

+

+static int

+bls_keyval_cmp(struct bls_entry *e0, struct bls_entry *e1, const char *keyname)

+{

+  char *val0, *val1;

+

+  val0 = bls_get_val (e0, keyname, NULL);

+  val1 = bls_get_val (e1, keyname, NULL);

+

+  if (val1 && !val0)

+    return 1;

+

+  if (val0 && !val1)

+    return -1;

+

+  if (!val0 && !val1)

+    return 0;

+

+  return nulcmp(val0, val1, (void_cmp_t)vercmp);

+}

+

+static int bls_cmp(const void *p0, const void *p1, void *state UNUSED)

+{

+  struct bls_entry * e0 = *(struct bls_entry **)p0;

+  struct bls_entry * e1 = *(struct bls_entry **)p1;

+  int rc = 0;

+

+  rc = bls_keyval_cmp (e0, e1, "id");

+

+  if (rc == 0)

+    rc = bls_keyval_cmp (e0, e1, "title");

+

+  if (rc == 0)

+    rc = bls_keyval_cmp (e0, e1, "linux");

+

+  return rc;

+}

+

+static int read_entry (

     const char *filename,

-    const struct grub_dirhook_info *info __attribute__ ((unused)),

-    void *data __attribute__ ((unused)))

+    const struct grub_dirhook_info *info UNUSED,

+    void *data)

 {

   grub_size_t n;

   char *p;

   grub_file_t f = NULL;

   grub_off_t sz;

-  char *title = NULL, *options = NULL, *clinux = NULL, *initrd = NULL, *src = NULL;

-  const char *args[2] = { NULL, NULL };

+  struct bls_entry *entry;

+  const char *dirname= (const char *)data;

+  const char *devid = grub_env_get ("boot");

+

+  grub_dprintf ("blscfg", "filename: \"%s\"\n", filename);

   if (filename[0] == '.')

     return 0;

@@ -67,7 +440,7 @@ static int parse_entry (

   if (grub_strcmp (filename + n - 5, ".conf") != 0)

     return 0;

-  p = grub_xasprintf (GRUB_BLS_CONFIG_PATH "%s", filename);

+  p = grub_xasprintf ("(%s)%s/%s", devid, dirname, filename);

   f = grub_file_open (p);

   if (!f)

@@ -77,54 +450,169 @@ static int parse_entry (

   if (sz == GRUB_FILE_SIZE_UNKNOWN || sz > 1024*1024)

     goto finish;

+  entry = bls_new_entry();

+  if (!entry)

+    goto finish;

+

   for (;;)

     {

       char *buf;

+      char *separator;

+      int rc;

       buf = grub_file_getline (f);

       if (!buf)

 	break;

-      if (grub_strncmp (buf, "title ", 6) == 0)

-	{

-	  grub_free (title);

-	  title = grub_strdup (buf + 6);

-	  if (!title)

-	    goto finish;

-	}

-      else if (grub_strncmp (buf, "options ", 8) == 0)

-	{

-	  grub_free (options);

-	  options = grub_strdup (buf + 8);

-	  if (!options)

-	    goto finish;

-	}

-      else if (grub_strncmp (buf, "linux ", 6) == 0)

-	{

-	  grub_free (clinux);

-	  clinux = grub_strdup (buf + 6);

-	  if (!clinux)

-	    goto finish;

-	}

-      else if (grub_strncmp (buf, "initrd ", 7) == 0)

+      while (buf && buf[0] && (buf[0] == ' ' || buf[0] == '\t'))

+	buf++;

+      if (buf[0] == '#')

+	continue;

+

+      separator = grub_strchr (buf, ' ');

+

+      if (!separator)

+	separator = grub_strchr (buf, '\t');

+

+      if (!separator || separator[1] == '\0')

 	{

-	  grub_free (initrd);

-	  initrd = grub_strdup (buf + 7);

-	  if (!initrd)

-	    goto finish;

+	  grub_free (buf);

+	  break;

 	}

-      grub_free(buf);

+      separator[0] = '\0';

+

+      rc = bls_add_keyval (entry, buf, separator+1);

+      grub_free (buf);

+      if (rc < 0)

+	break;

+    }

+

+  grub_qsort(&entry->keyvals[0], entry->nkeyvals, sizeof (struct keyval *),

+	     keyval_cmp, NULL);

+

+finish:

+  grub_free (p);

+

+  if (f)

+    grub_file_close (f);

+

+  return 0;

+}

+

+static grub_envblk_t saved_env = NULL;

+

+static int

+save_var (const char *name, const char *value, void *whitelist UNUSED)

+{

+  const char *val = grub_env_get (name);

+  grub_dprintf("blscfg", "saving \"%s\"\n", name);

+

+  if (val)

+    grub_envblk_set (saved_env, name, value);

+

+  return 0;

+}

+

+static int

+unset_var (const char *name, const char *value UNUSED, void *whitelist)

+{

+  grub_dprintf("blscfg", "restoring \"%s\"\n", name);

+  if (! whitelist)

+    {

+      grub_env_unset (name);

+      return 0;

     }

-  if (!linux)

+  if (test_whitelist_membership (name,

+				 (const grub_env_whitelist_t *) whitelist))

+    grub_env_unset (name);

+

+  return 0;

+}

+

+static char **bls_make_list (struct bls_entry *entry, const char *key, int *num)

+{

+  int last = -1;

+  char *val;

+

+  int nlist = 0;

+  char **list = NULL;

+

+  list = grub_malloc (sizeof (char *));

+  if (!list)

+    return NULL;

+  list[0] = NULL;

+

+  while (1)

+    {

+      char **new;

+

+      val = bls_get_val (entry, key, &last);

+      if (!val)

+	break;

+

+      new = grub_realloc (list, (nlist + 2) * sizeof (char *));

+      if (!new)

+	break;

+

+      list = new;

+      list[nlist++] = val;

+      list[nlist] = NULL;

+  }

+

+  if (num)

+    *num = nlist;

+

+  return list;

+}

+

+static void create_entry (struct bls_entry *entry, const char *cfgfile)

+{

+  int argc = 0;

+  const char **argv = NULL;

+

+  char *title = NULL;

+  char *clinux = NULL;

+  char *options = NULL;

+  char *initrd = NULL;

+  char *id = NULL;

+  char *hotkey = NULL;

+

+  char *users = NULL;

+  char **classes = NULL;

+

+  char **args = NULL;

+

+  char *src = NULL;

+  int i;

+

+  grub_dprintf("blscfg", "%s got here\n", __func__);

+  clinux = bls_get_val (entry, "linux", NULL);

+  if (!clinux)

     {

-      grub_printf ("Skipping file %s with no 'linux' key.", p);

+      grub_dprintf ("blscfg", "Skipping file %s with no 'linux' key.\n", cfgfile);

       goto finish;

     }

-  args[0] = title ? title : filename;

+  title = bls_get_val (entry, "title", NULL);

+  options = bls_get_val (entry, "options", NULL);

+  initrd = bls_get_val (entry, "initrd", NULL);

+  id = bls_get_val (entry, "id", NULL);

+  hotkey = bls_get_val (entry, "grub_hotkey", NULL);

+  users = bls_get_val (entry, "grub_users", NULL);

+  classes = bls_make_list (entry, "grub_class", NULL);

+  args = bls_make_list (entry, "grub_arg", &argc);

+

+  argc += 1;

+  argv = grub_malloc ((argc + 1) * sizeof (char *));

+  argv[0] = title ? title : clinux;

+  for (i = 1; i < argc; i++)

+    argv[i] = args[i-1];

+  argv[argc] = NULL;

+

+  grub_dprintf("blscfg", "adding menu entry for \"%s\"\n", title);

   src = grub_xasprintf ("load_video\n"

 			"set gfx_payload=keep\n"

 			"insmod gzio\n"

@@ -133,40 +621,219 @@ static int parse_entry (

 			GRUB_BOOT_DEVICE, clinux, options ? " " : "", options ? options : "",

 			initrd ? GRUB_INITRD_CMD " " : "", initrd ? GRUB_BOOT_DEVICE : "", initrd ? initrd : "", initrd ? "\n" : "");

-  grub_normal_add_menu_entry (1, args, NULL, NULL, "bls", NULL, NULL, src, 0);

+  grub_normal_add_menu_entry (argc, argv, classes, id, users, hotkey, NULL, src, 0);

 finish:

-  grub_free (p);

-  grub_free (title);

-  grub_free (options);

-  grub_free (clinux);

-  grub_free (initrd);

-  grub_free (src);

+  if (classes)

+      grub_free (classes);

+  grub_dprintf("blscfg", "%s got here\n", __func__);

+  if (args)

+      grub_free (args);

+

+  if (argv)

+      grub_free (argv);

+

+  if (src)

+      grub_free (src);

+  grub_dprintf("blscfg", "%s got here\n", __func__);

+}

+

+struct find_entry_info {

+	grub_device_t dev;

+	grub_fs_t fs;

+	int efi;

+};

+

+/*

+ * filename: if the directory is /EFI/something/ , filename is "something"

+ * info: unused

+ * data: the filesystem object the file is on.

+ */

+static int find_entry (const char *filename,

+		       const struct grub_dirhook_info *dirhook_info UNUSED,

+		       void *data)

+{

+  struct find_entry_info *info = (struct find_entry_info *)data;

+  grub_file_t f = NULL;

+  char *grubenv_path = NULL;

+  grub_envblk_t env = NULL;

+  char *default_blsdir = NULL;