xnu-7195.101.1.tar.gz

[apple/xnu.git] / bsd / sys / linker_set.h

diff --git a/bsd/sys/linker_set.h b/bsd/sys/linker_set.h
index 1aea008487a9be3cc5963709dc1a9e97434053cf..23b3a38a31e5a985e924a176a864327ba23fb579 100644 (file)
--- a/bsd/sys/linker_set.h
+++ b/bsd/sys/linker_set.h
@@ -2,7 +2,7 @@
  * Copyright (c) 2006-2008 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * Copyright (c) 2006-2008 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@

- * 
+ *

  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in


@@ -11,10 +11,10 @@
  * unlawful or unlicensed copies of an Apple operating system, or to
  * circumvent, violate, or enable the circumvention or violation of, any
  * terms of an Apple operating system software license agreement.
  * unlawful or unlicensed copies of an Apple operating system, or to
  * circumvent, violate, or enable the circumvention or violation of, any
  * terms of an Apple operating system software license agreement.

- * 
+ *

  * Please obtain a copy of the License at
  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  * Please obtain a copy of the License at
  * http://www.opensource.apple.com/apsl/ and read it before using this file.

- * 
+ *

  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,


@@ -22,7 +22,7 @@
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.

- * 
+ *

  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  *
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  *
  *


@@ -62,9 +62,9 @@
  * The following macros are used to declare global sets of objects, which
  * are collected by the linker into a `linker set' as defined below.
  * For Mach-O, this is done by constructing a separate segment inside the
  * The following macros are used to declare global sets of objects, which
  * are collected by the linker into a `linker set' as defined below.
  * For Mach-O, this is done by constructing a separate segment inside the

- * __DATA section for each set.  The contents of this segment are an array
+ * __DATA_CONST section for each set.  The contents of this segment are an array

  * of pointers to the objects in the set.
  * of pointers to the objects in the set.

- * 
+ *

  * Note that due to limitations of the Mach-O format, there cannot
  * be more than 255 sections in a segment, so linker set usage should be
  * conserved.  Set names may not exceed 16 characters.
  * Note that due to limitations of the Mach-O format, there cannot
  * be more than 255 sections in a segment, so linker set usage should be
  * conserved.  Set names may not exceed 16 characters.


@@ -73,12 +73,41 @@
 #ifdef KERNEL
 # include <mach-o/loader.h>
 # include <libkern/kernel_mach_header.h>
 #ifdef KERNEL
 # include <mach-o/loader.h>
 # include <libkern/kernel_mach_header.h>

+
+# define MACH_HEADER_TYPE kernel_mach_header_t
+# define GETSECTIONDATA_VARIANT getsectdatafromheader
+# define SECTDATA_SIZE_TYPE unsigned long
+# define MH_EXECUTE_HEADER &_mh_execute_header
+# define IMAGE_SLIDE_CORRECT 0

 #else
 # include <mach-o/ldsyms.h>
 # include <mach-o/getsect.h>
 # include <mach-o/loader.h>
 #else
 # include <mach-o/ldsyms.h>
 # include <mach-o/getsect.h>
 # include <mach-o/loader.h>

+# include <mach-o/dyld.h>
+# include <crt_externs.h>
+
+# if __LP64__
+#  define MACH_HEADER_TYPE struct mach_header_64
+#  define GETSECTIONDATA_VARIANT getsectdatafromheader_64
+#  define SECTDATA_SIZE_TYPE uint64_t
+#  define MH_EXECUTE_HEADER _NSGetMachExecuteHeader()
+# else
+#  define MACH_HEADER_TYPE struct mach_header
+#  define GETSECTIONDATA_VARIANT getsectdatafromheader
+#  define SECTDATA_SIZE_TYPE uint32_t
+#  define MH_EXECUTE_HEADER _NSGetMachExecuteHeader()
+# endif

 #endif
 
 #endif
 

+#if __LP64__
+# define LINKER_SET_ENTRY_PACKED
+# define LINKER_SET_SEGMENT __DATA_CONST
+# define LINKER_SET_SEGMENT_CSTR "__DATA_CONST"
+#else
+# define LINKER_SET_ENTRY_PACKED __attribute__((packed))
+# define LINKER_SET_SEGMENT __DATA
+# define LINKER_SET_SEGMENT_CSTR "__DATA"
+#endif

 
 /*
  * Private macros, not to be used outside this header file.
 
 /*
  * Private macros, not to be used outside this header file.


@@ -86,36 +115,42 @@
  * The objective of this macro stack is to produce the following output,
  * given SET and SYM as arguments:
  *
  * The objective of this macro stack is to produce the following output,
  * given SET and SYM as arguments:
  *

- *  void const * __set_SET_sym_SYM __attribute__((section("__DATA,SET"))) = & SYM
+ *  void const * __set_SET_sym_SYM __attribute__((section("__DATA_CONST,SET"))) = & SYM

  */
  */

+
+/* Wrap entries in a type that can be blacklisted from KASAN */
+struct linker_set_entry {
+       void *ptr;
+} LINKER_SET_ENTRY_PACKED;
+

 #ifdef __LS_VA_STRINGIFY__
 #  undef __LS_VA_STRINGIFY__
 #endif
 #ifdef __LS_VA_STRCONCAT__
 #  undef __LS_VA_STRCONCAT__
 #endif
 #ifdef __LS_VA_STRINGIFY__
 #  undef __LS_VA_STRINGIFY__
 #endif
 #ifdef __LS_VA_STRCONCAT__
 #  undef __LS_VA_STRCONCAT__
 #endif

-#define __LS_VA_STRINGIFY(_x...)       #_x
-#define __LS_VA_STRCONCAT(_x,_y)       __LS_VA_STRINGIFY(_x,_y)
-#define __LINKER_MAKE_SET(_set, _sym)                                  \
-       /*__unused*/ /*static*/ void const * /*const*/ __set_##_set##_sym_##_sym                \
-       __attribute__ ((section(__LS_VA_STRCONCAT(__DATA,_set)),used)) = (void *)&_sym
+#define __LS_VA_STRINGIFY(_x ...)        #_x
+#define __LS_VA_STRCONCAT(_x, _y)        __LS_VA_STRINGIFY(_x,_y)
+#define __LINKER_MAKE_SET(_set, _sym)                                   \
+       /*__unused*/ /*static*/ const struct linker_set_entry /*const*/ __set_##_set##_sym_##_sym               \
+       __attribute__ ((section(__LS_VA_STRCONCAT(LINKER_SET_SEGMENT,_set)),used)) = { (void *)&_sym }

 /* the line above is very fragile - if your compiler breaks linker sets,
 /* the line above is very fragile - if your compiler breaks linker sets,

-   just play around with "static", "const", "used" etc. :-) */
+ *  just play around with "static", "const", "used" etc. :-) */

 
 /*
  * Public macros.
  */
 
 /*
  * Public macros.
  */

-#define LINKER_SET_ENTRY(_set, _sym)   __LINKER_MAKE_SET(_set, _sym)
+#define LINKER_SET_ENTRY(_set, _sym)    __LINKER_MAKE_SET(_set, _sym)

 
 /*
  * FreeBSD compatibility.
  */
 #ifdef __APPLE_API_OBSOLETE
 
 /*
  * FreeBSD compatibility.
  */
 #ifdef __APPLE_API_OBSOLETE

-# define TEXT_SET(_set, _sym)  __LINKER_MAKE_SET(_set, _sym)
-# define DATA_SET(_set, _sym)  __LINKER_MAKE_SET(_set, _sym)
-# define BSS_SET(_set, _sym)   __LINKER_MAKE_SET(_set, _sym)
-# define ABS_SET(_set, _sym)   __LINKER_MAKE_SET(_set, _sym)
-# define SET_ENTRY(_set, _sym) __LINKER_MAKE_SET(_set, _sym)
+# define TEXT_SET(_set, _sym)   __LINKER_MAKE_SET(_set, _sym)
+# define DATA_SET(_set, _sym)   __LINKER_MAKE_SET(_set, _sym)
+# define BSS_SET(_set, _sym)    __LINKER_MAKE_SET(_set, _sym)
+# define ABS_SET(_set, _sym)    __LINKER_MAKE_SET(_set, _sym)
+# define SET_ENTRY(_set, _sym)  __LINKER_MAKE_SET(_set, _sym)

 #endif /* __APPLE_API_OBSOLETE */
 
 /*
 #endif /* __APPLE_API_OBSOLETE */
 
 /*


@@ -140,39 +175,26 @@
  *     Iterates over the members of _set within _object.  Since the set contains
  *     pointers to its elements, for a set of elements of type etyp, _pvar must
  *     be (etyp **).
  *     Iterates over the members of _set within _object.  Since the set contains
  *     pointers to its elements, for a set of elements of type etyp, _pvar must
  *     be (etyp **).

- * set_member_type **LINKER_SET_OBJECT_ITEM(_object, _set, _i)
- *     Returns a pointer to the _i'th element of _set within _object.
- *
- * void **LINKER_SET_BEGIN(_set)
- * void **LINKER_SET_LIMINT(_set)

  * LINKER_SET_FOREACH((set_member_type **)_pvar, _cast, _set)
  * LINKER_SET_FOREACH((set_member_type **)_pvar, _cast, _set)

- * set_member_type **LINKER_SET_ITEM(_set, _i)
- *     These versions implicitly reference the kernel/application object.
- * 
+ *

  * Example of _cast: For the _pvar "struct sysctl_oid **oidpp", _cast would be
  * Example of _cast: For the _pvar "struct sysctl_oid **oidpp", _cast would be

- *                  "struct sysctl_oid **"
+ *                   "struct sysctl_oid **"

  *
  */
 
  *
  */
 

-#define LINKER_SET_OBJECT_BEGIN(_object, _set) __linker_set_object_begin(_object, _set)
-#define LINKER_SET_OBJECT_LIMIT(_object, _set) __linker_set_object_limit(_object, _set)
+#define LINKER_SET_OBJECT_BEGIN(_object, _set)  __linker_set_object_begin(_object, _set)
+#define LINKER_SET_OBJECT_LIMIT(_object, _set)  __linker_set_object_limit(_object, _set)

 
 

-#define LINKER_SET_OBJECT_FOREACH(_object, _pvar, _cast, _set)         \
-       for (_pvar = (_cast) LINKER_SET_OBJECT_BEGIN(_object, _set);    \
-            _pvar < (_cast) LINKER_SET_OBJECT_LIMIT(_object, _set);    \
+#define LINKER_SET_OBJECT_FOREACH(_object, _pvar, _cast, _set)          \
+       for (_pvar = (_cast) LINKER_SET_OBJECT_BEGIN(_object, _set);    \
+            _pvar < (_cast) LINKER_SET_OBJECT_LIMIT(_object, _set);    \

             _pvar++)
 
             _pvar++)
 

-#define LINKER_SET_OBJECT_ITEM(_object, _set, _i)                      \
-       ((LINKER_SET_OBJECT_BEGIN(_object, _set))[_i])
+#define LINKER_SET_OBJECT_ITEM(_object, _cast, _set, _i)                \
+       (((_cast)(LINKER_SET_OBJECT_BEGIN(_object, _set)))[_i])

 
 

-#define LINKER_SET_BEGIN(_set)                                         \
-               LINKER_SET_OBJECT_BEGIN((kernel_mach_header_t *)&_mh_execute_header, _set)
-#define LINKER_SET_LIMIT(_set)                                         \
-               LINKER_SET_OBJECT_LIMIT((kernel_mach_header_t *)&_mh_execute_header, _set)
-#define LINKER_SET_FOREACH(_pvar, _cast, _set)                                 \
-       LINKER_SET_OBJECT_FOREACH((kernel_mach_header_t *)&_mh_execute_header, _pvar, _cast, _set)
-#define LINKER_SET_ITEM(_set, _i)                                      \
-       LINKER_SET_OBJECT_ITEM((kernel_mach_header_t *)&_mh_execute_header, _set, _i)
+#define LINKER_SET_FOREACH(_pvar, _cast, _set)                                  \
+       LINKER_SET_OBJECT_FOREACH((MACH_HEADER_TYPE *)MH_EXECUTE_HEADER, _pvar, _cast, _set)

 
 /*
  * Implementation.
 
 /*
  * Implementation.


@@ -183,35 +205,59 @@
  *     Returns an upper bound to the linker set (base + size).
  */
 
  *     Returns an upper bound to the linker set (base + size).
  */
 

+static __inline intptr_t
+__linker_get_slide(struct mach_header *_header)
+{
+#ifndef KERNEL
+       /*
+        * Gross.
+        *
+        * We cannot get the image slide directly from the header, so we need to
+        * determine the image's index and ask for the slide of that index.
+        */
+       uint32_t i = 0;
+       for (i = 0; i < _dyld_image_count(); i++) {
+               const struct mach_header *hdr = _dyld_get_image_header(i);
+               if (_header == hdr) {
+                       return _dyld_get_image_vmaddr_slide(i);
+               }
+       }
+       return 0;
+#else
+       (void)_header;
+       return 0;
+#endif
+}
+

 static __inline void **
 static __inline void **

-__linker_set_object_begin(kernel_mach_header_t *_header, const char *_set)
-     __attribute__((__const__));
+__linker_set_object_begin(MACH_HEADER_TYPE *_header, const char *_set)
+__attribute__((__const__));

 static __inline void **
 static __inline void **

-__linker_set_object_begin(kernel_mach_header_t *_header, const char *_set)
+__linker_set_object_begin(MACH_HEADER_TYPE *_header, const char *_set)

 {
 {

-       void *_set_begin;
-       unsigned long _size;
+       char *_set_begin;
+       SECTDATA_SIZE_TYPE _size;

 
 

-       _set_begin = getsectdatafromheader(_header, "__DATA", _set, &_size);
-       return( (void **) _set_begin );
+       _set_begin = (char *)GETSECTIONDATA_VARIANT(_header, LINKER_SET_SEGMENT_CSTR, _set, &_size);
+       _set_begin += __linker_get_slide((struct mach_header *)_header);
+       return (void **)(uintptr_t)_set_begin;

 }
 
 static __inline void **
 }
 
 static __inline void **

-__linker_set_object_limit(kernel_mach_header_t *_header, const char *_set)
-     __attribute__((__const__));
+__linker_set_object_limit(MACH_HEADER_TYPE *_header, const char *_set)
+__attribute__((__const__));

 static __inline void **
 static __inline void **

-__linker_set_object_limit(kernel_mach_header_t *_header, const char *_set)
+__linker_set_object_limit(MACH_HEADER_TYPE *_header, const char *_set)

 {
 {

-       void *_set_begin;
-       unsigned long _size;
+       char *_set_begin;
+       SECTDATA_SIZE_TYPE _size;
+
+       _set_begin = (char *)GETSECTIONDATA_VARIANT(_header, LINKER_SET_SEGMENT_CSTR, _set, &_size);
+       _set_begin += __linker_get_slide((struct mach_header *)_header);

 
 

-       _set_begin = getsectdatafromheader(_header, "__DATA", _set, &_size);
-       
-       return ((void **) ((uintptr_t) _set_begin + _size));
+       return (void **) ((uintptr_t) _set_begin + _size);

 }
 
 #endif /* !KERNEL || __APPLE_API_PRIVATE */
 
 #endif /* _SYS_LINKER_SET_H_ */
 }
 
 #endif /* !KERNEL || __APPLE_API_PRIVATE */
 
 #endif /* _SYS_LINKER_SET_H_ */

-
-