From bf43c6f1b92a5c97edbd2541b67cf2e794fff074 Mon Sep 17 00:00:00 2001
From: Peter Jones <pjones@redhat.com>
Date: Mon, 1 Oct 2012 13:24:37 -0400
Subject: [PATCH] Pass "\x[[:hex:]][[:hex:]]" straight through unmolested.

---
 grub-core/commands/wildcard.c | 16 +++++++++++++++-
 grub-core/lib/cmdline.c       | 34 ++++++++++++++++++++++++++++++++--
 grub-core/script/execute.c    | 43 +++++++++++++++++++++++++++++++++++++------
 3 files changed, 84 insertions(+), 9 deletions(-)

diff --git a/grub-core/commands/wildcard.c b/grub-core/commands/wildcard.c
index 9b4e72766ff..02c46f9fdfa 100644
--- a/grub-core/commands/wildcard.c
+++ b/grub-core/commands/wildcard.c
@@ -462,6 +462,12 @@ check_file (const char *dir, const char *basename)
   return ctx.found;
 }
 
+static int
+is_hex(char c)
+{
+  return ((c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F'));
+}
+
 static void
 unescape (char *out, const char *in, const char *end)
 {
@@ -470,7 +476,15 @@ unescape (char *out, const char *in, const char *end)
 
   for (optr = out, iptr = in; iptr < end;)
     {
-      if (*iptr == '\\' && iptr + 1 < end)
+      if (*iptr == '\\' && iptr + 3 < end && iptr[1] == 'x' && is_hex(iptr[2]) && is_hex(iptr[3]))
+	{
+	  *optr++ = *iptr++;
+	  *optr++ = *iptr++;
+	  *optr++ = *iptr++;
+	  *optr++ = *iptr++;
+	  continue;
+	}
+      else if (*iptr == '\\' && iptr + 1 < end)
 	{
 	  *optr++ = iptr[1];
 	  iptr += 2;
diff --git a/grub-core/lib/cmdline.c b/grub-core/lib/cmdline.c
index d5e10ee8798..0a5b2afb94b 100644
--- a/grub-core/lib/cmdline.c
+++ b/grub-core/lib/cmdline.c
@@ -20,6 +20,12 @@
 #include <grub/lib/cmdline.h>
 #include <grub/misc.h>
 
+static int
+is_hex(char c)
+{
+  return ((c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F'));
+}
+
 static unsigned int check_arg (char *c, int *has_space)
 {
   int space = 0;
@@ -27,7 +33,13 @@ static unsigned int check_arg (char *c, int *has_space)
 
   while (*c)
     {
-      if (*c == '\\' || *c == '\'' || *c == '"')
+      if (*c == '\\' && *(c+1) == 'x' && is_hex(*(c+2)) && is_hex(*(c+3)))
+	{
+	  size += 4;
+	  c += 4;
+	  continue;
+	}
+      else if (*c == '\\' || *c == '\'' || *c == '"')
 	size++;
       else if (*c == ' ')
 	space = 1;
@@ -85,7 +97,25 @@ int grub_create_loader_cmdline (int argc, char *argv[], char *buf,
 
       while (*c)
 	{
-	  if (*c == '\\' || *c == '\'' || *c == '"')
+	  if (*c == ' ')
+	    {
+	      *buf++ = '\\';
+	      *buf++ = 'x';
+	      *buf++ = '2';
+	      *buf++ = '0';
+	      c++;
+	      continue;
+	    }
+	  else if (*c == '\\' && *(c+1) == 'x' &&
+		   is_hex(*(c+2)) && is_hex(*(c+3)))
+	    {
+	      *buf++ = *c++;
+	      *buf++ = *c++;
+	      *buf++ = *c++;
+	      *buf++ = *c++;
+	      continue;
+	    }
+	  else if (*c == '\\' || *c == '\'' || *c == '"')
 	    *buf++ = '\\';
 
 	  *buf++ = *c;
diff --git a/grub-core/script/execute.c b/grub-core/script/execute.c
index ab78ca87f90..cf6cd6601d6 100644
--- a/grub-core/script/execute.c
+++ b/grub-core/script/execute.c
@@ -55,6 +55,12 @@ static struct grub_script_scope *scope = 0;
 /* Wildcard translator for GRUB script.  */
 struct grub_script_wildcard_translator *grub_wildcard_translator;
 
+static int
+is_hex(char c)
+{
+  return ((c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F'));
+}
+
 static char*
 wildcard_escape (const char *s)
 {
@@ -71,7 +77,15 @@ wildcard_escape (const char *s)
   i = 0;
   while ((ch = *s++))
     {
-      if (ch == '*' || ch == '\\' || ch == '?')
+      if (ch == '\\' && s[0] == 'x' && is_hex(s[1]) && is_hex(s[2]))
+	{
+	  p[i++] = ch;
+	  p[i++] = *s++;
+	  p[i++] = *s++;
+	  p[i++] = *s++;
+	  continue;
+	}
+      else if (ch == '*' || ch == '\\' || ch == '?')
 	p[i++] = '\\';
       p[i++] = ch;
     }
@@ -95,7 +109,14 @@ wildcard_unescape (const char *s)
   i = 0;
   while ((ch = *s++))
     {
-      if (ch == '\\')
+      if (ch == '\\' && s[0] == 'x' && is_hex(s[1]) && is_hex(s[2]))
+	{
+	  p[i++] = '\\';
+	  p[i++] = *s++;
+	  p[i++] = *s++;
+	  p[i++] = *s++;
+	}
+      else if (ch == '\\')
 	p[i++] = *s++;
       else
 	p[i++] = ch;
@@ -397,10 +418,20 @@ parse_string (const char *str,
     switch (*ptr)
       {
       case '\\':
-	escaped = !escaped;
-	if (!escaped && put)
-	  *(put++) = '\\';
-	ptr++;
+	if (!escaped && put && *(ptr+1) == 'x' && is_hex(*(ptr+2)) && is_hex(*(ptr+3)))
+	  {
+	    *(put++) = *ptr++;
+	    *(put++) = *ptr++;
+	    *(put++) = *ptr++;
+	    *(put++) = *ptr++;
+	  }
+	else
+	  {
+	    escaped = !escaped;
+	    if (!escaped && put)
+	      *(put++) = '\\';
+	    ptr++;
+	  }
 	break;
       case '$':
 	if (escaped)