Merge upstream 0.165 SHA '203f0a3'

* git merge 203f0a3
* See all upstream changes since the previous merge
  in branch aosp/upstream-master:
    git diff 9d1e236..203f0a3
* Android relevant upstream changes:
  * Version number changed from 0.164 to 0.165
  * libelf now depends on zlib
* Changed version number in generated files:
    version.h, config.h
* No change to generated files:
    libdw/known-dwarf.h
* Updated libelf/Android.mk:
  * added new source files:
     gelf_getchdr.c elf{32,64}_getchdr.c elf_compress.c
  * added LOCAL_STATIC_LIBRARIES := libz

Change-Id: Ieb306d84ffcaf680ad6e74da28fcc8efbf00592a

25 files changed, 1361 insertions, 35 deletions

diff --git a/libelf/Android.mk b/libelf/Android.mk
index 1c0195c4..53d47be4 100755
--- a/libelf/Android.mk
+++ b/libelf/Android.mk
@@ -17,6 +17,7 @@ LOCAL_PATH := $(call my-dir)
 LIBELF_SRC_FILES := \
 	elf32_checksum.c \
 	elf32_fsize.c \
+	elf32_getchdr.c \
 	elf32_getehdr.c \
 	elf32_getphdr.c \
 	elf32_getshdr.c \
@@ -29,6 +30,7 @@ LIBELF_SRC_FILES := \
 	elf32_xlatetom.c \
 	elf64_checksum.c \
 	elf64_fsize.c \
+	elf64_getchdr.c \
 	elf64_getehdr.c \
 	elf64_getphdr.c \
 	elf64_getshdr.c \
@@ -42,6 +44,7 @@ LIBELF_SRC_FILES := \
 	elf_begin.c \
 	elf_clone.c \
 	elf_cntl.c \
+	elf_compress.c \
 	elf_end.c \
 	elf_error.c \
 	elf_fill.c \
@@ -82,6 +85,7 @@ LIBELF_SRC_FILES := \
 	gelf_checksum.c \
 	gelf_fsize.c \
 	gelf_getauxv.c \
+	gelf_getchdr.c \
 	gelf_getclass.c \
 	gelf_getdyn.c \
 	gelf_getehdr.c \
@@ -148,6 +152,8 @@ LOCAL_CFLAGS += -Wno-pointer-arith
 
 LOCAL_MODULE := libelf
 
+LOCAL_STATIC_LIBRARIES := libz
+
 LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)
 
 include $(BUILD_HOST_STATIC_LIBRARY)
@@ -171,6 +177,8 @@ LOCAL_C_INCLUDES := \
 
 LOCAL_C_INCLUDES += $(LOCAL_PATH)/../bionic-fixup
 
+LOCAL_STATIC_LIBRARIES := libz
+
 LOCAL_CFLAGS += -DHAVE_CONFIG_H -std=gnu99 -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64
 
 # to suppress the "pointer of type ‘void *’ used in arithmetic" warning
diff --git a/libelf/ChangeLog b/libelf/ChangeLog
index fbe8e3ae..afe6a6a5 100644
--- a/libelf/ChangeLog
+++ b/libelf/ChangeLog
@@ -1,3 +1,83 @@
+2016-01-22  Chih-Hung Hsieh <chh@google.com>
+
+	* elf_compress.c (__libelf_compress): Move nested function
+	'do_deflate_cleanup' to file scope to compile with clang.
+	* elf_strptr.c (elf_strptr): Move nested function 'get_zdata'
+	to file scope to compile with clang.
+
+2016-01-13  Mark Wielaard  <mjw@redhat.com>
+
+	* libelf.h: Check SHF_COMPRESSED is defined. If not define it and the
+	associated ELF compression types/defines.
+
+2015-11-26  Mark Wielaard  <mjw@redhat.com>
+
+	* elf_compress.c (__libelf_decompress_elf): New function, extracted
+	from...
+	(elf_compress): here. Check zdata_base use __libelf_decompress_elf.
+	* elf_strptr.c (elf_strptr): If SHF_COMPRESSED check, uncompress and
+	use zdata.
+	* libelfP.h (struct Elf_Scn): Add zdata_size and zdata_align.
+	(__libelf_decompress_elf): New internal function definition.
+
+2015-10-21  Mark Wielaard  <mjw@redhat.com>
+
+	* Makefile.am (libelf_a_SOURCES): Add elf_compress.c and
+	elf_compress_gnu.c.
+	* elf_compress.c: New file.
+	* elf_compress_gnu.c: Likewise.
+	* elf_begin.c (file_read_elf): Make a writable copy of the shdrs
+	for ELF_C_READ_MMAP.
+	* elf_end.c (elf_end): Free zdata_base.
+	* elf_error.c: Add ELF_E_ALREADY_COMPRESSED,
+	ELF_E_UNKNOWN_COMPRESSION_TYPE, ELF_E_COMPRESS_ERROR and
+	ELF_E_DECOMPRESS_ERROR.
+	* elf_data.c (__libelf_data_type): New internal function extracted
+	from convert_data.
+	(convert_data): Handle SHF_COMPRESSED.
+	* elf32_updatenull.c (updatenull_wrlock): Check sh_entsize against
+	uncompressed section data size if SHF_COMPRESSED.
+	* elf32_getshdr.c (load_shdr_wrlock): Adjust assert to account for
+	ELF_C_READ_MMAP.
+	* libelf.h: Define elf_compress and elf_compress_gnu.
+	* libelf.map (ELFUTILS_1.7): Add elf_compress and elf_compress_gnu.
+	* libelfP.h: Add ELF_E_ALREADY_COMPRESSED,
+	ELF_E_UNKNOWN_COMPRESSION_TYPE, ELF_E_COMPRESS_ERROR and
+	ELF_E_DECOMPRESS_ERROR. Define __libelf_data_type.
+	(__libelf_compress): New internal function definition.
+	(__libelf_decompress): Likewise.
+	(__libelf_reset_rawdata): Likewise.
+	(__libelf_data_type): Likewise.
+	(struct Elf_Scn): Add zdata_base.
+
+2015-11-19  Mark Wielaard  <mjw@redhat.com>
+
+	* Makefile.am (libelf_a_SOURCES): Add elf32_getchdr.c,
+	elf64_getchdr.c and gelf_getchdr.c.
+	(noinst_HEADERS): Add chdr_xlate.h.
+	* abstract.h: Define Chdr32 and Chdr64.
+	* chdr_xlate.h: New file.
+	* elf32_getchdr.c: New file.
+	* elf64_getchdr.c: New file.
+	* elf_error.c: Add ELF_E_NOT_COMPRESSED, ELF_E_INVALID_SECTION_TYPE
+	and ELF_E_INVALID_SECTION_FLAGS.
+	* elf_getdata.c (__libelf_set_rawdata_wrlock): Set d_type to
+	ELF_T_CHDR for SHF_COMPRESSED sections.
+	* exttypes.h: Add Chdr32 and Chdr64.
+	* gelf.h (GElf_Chdr): New typedef.
+	(gelf_getchdr): New function definition.
+	* gelf_fsize.c (__libelf_type_sizes): Add ELF_T_CHDR.
+	* gelf_getchdr.c: New file.
+	* gelf_xlate.c (__elf_xfctstom): Add ELF_T_CHDR cvt_chdr.
+	* gelf_xlate.h: Add Chdr.
+	* libelf.h (Elf_Type): Add ELF_T_CHDR.
+	(elf32_getchdr): New function definition.
+	(elf64_getchdr): Likewise.
+	* libelf.map (ELFUTILS_1.7): New sections add elf32_getchdr,
+	elf64_getchdr and gelf_getchdr.
+	* libelfP.h: Add ELF_E_NOT_COMPRESSED, ELF_E_INVALID_SECTION_TYPE
+	and ELF_E_INVALID_SECTION_FLAGS.
+
 2015-10-16  Mark Wielaard  <mjw@redhat.com>
 
 	* Makefile.am (libelf_so_LDLIBS): Add -lz.
diff --git a/libelf/Makefile.am b/libelf/Makefile.am
index 4a4131c1..167a8322 100644
--- a/libelf/Makefile.am
+++ b/libelf/Makefile.am
@@ -1,6 +1,6 @@
 ## Process this file with automake to create Makefile.in
 ##
-## Copyright (C) 1996-2010 Red Hat, Inc.
+## Copyright (C) 1996-2010, 2015 Red Hat, Inc.
 ## This file is part of elfutils.
 ##
 ## This file is free software; you can redistribute it and/or modify
@@ -88,7 +88,9 @@ libelf_a_SOURCES = elf_version.c elf_hash.c elf_error.c elf_fill.c \
 		   elf32_offscn.c elf64_offscn.c gelf_offscn.c \
 		   elf_getaroff.c \
 		   elf_gnu_hash.c \
-		   elf_scnshndx.c
+		   elf_scnshndx.c \
+		   elf32_getchdr.c elf64_getchdr.c gelf_getchdr.c \
+		   elf_compress.c elf_compress_gnu.c
 
 libelf_pic_a_SOURCES =
 am_libelf_pic_a_OBJECTS = $(libelf_a_SOURCES:.c=.os)
@@ -118,7 +120,8 @@ uninstall: uninstall-am
 	rm -f $(DESTDIR)$(libdir)/libelf.so
 
 noinst_HEADERS = elf.h abstract.h common.h exttypes.h gelf_xlate.h libelfP.h \
-		 version_xlate.h gnuhash_xlate.h note_xlate.h dl-hash.h
+		 version_xlate.h gnuhash_xlate.h note_xlate.h dl-hash.h \
+		 chdr_xlate.h
 EXTRA_DIST = libelf.map
 
 CLEANFILES += $(am_libelf_pic_a_OBJECTS) libelf.so.$(VERSION)
diff --git a/libelf/abstract.h b/libelf/abstract.h
index 53713eec..d4515f27 100644
--- a/libelf/abstract.h
+++ b/libelf/abstract.h
@@ -1,5 +1,5 @@
 /* Abstract description of component ELF types.
-   Copyright (C) 1998, 1999, 2000, 2002, 2004, 2007 Red Hat, Inc.
+   Copyright (C) 1998, 1999, 2000, 2002, 2004, 2007, 2015 Red Hat, Inc.
    This file is part of elfutils.
    Written by Ulrich Drepper <drepper@redhat.com>, 1998.
 
@@ -310,3 +310,21 @@ START (64, auxv_t, Ext##auxv_t)						      \
   TYPE_XLATE (Elf64_cvt_Addr1 (&tdest->a_un.a_val, &tsrc->a_un.a_val);)	      \
   TYPE_EXTRA (} a_un;)							      \
 END (64, Ext##auxv_t)
+
+/* Note that there is actual compression data right after the Chdr.
+   So we also have a separate conversion function for the whole
+   section.  */
+#define Chdr32(Ext) \
+START (32, Chdr, Ext##Chdr)						\
+  TYPE_NAME (ElfW2(32, Ext##Word), ch_type)				\
+  TYPE_NAME (ElfW2(32, Ext##Word), ch_size)				\
+  TYPE_NAME (ElfW2(32, Ext##Word), ch_addralign)			\
+END (32, Ext##Chdr)
+
+#define Chdr64(Ext) \
+START (64, Chdr, Ext##Chdr)						\
+  TYPE_NAME (ElfW2(64, Ext##Word), ch_type)				\
+  TYPE_NAME (ElfW2(64, Ext##Word), ch_reserved)				\
+  TYPE_NAME (ElfW2(64, Ext##Xword), ch_size)				\
+  TYPE_NAME (ElfW2(64, Ext##Xword), ch_addralign)			\
+END (64, Ext##Chdr)
diff --git a/libelf/chdr_xlate.h b/libelf/chdr_xlate.h
new file mode 100644
index 00000000..70782b43
--- /dev/null
+++ b/libelf/chdr_xlate.h
@@ -0,0 +1,33 @@
+#include "common.h"
+
+/* These functions convert a while section, one Chdr plus compression data.  */
+
+static void
+Elf32_cvt_chdr (void *dest, const void *src, size_t len, int encode)
+{
+  if (len == 0)
+    return;
+
+  /* Move everything over, if necessary, we only need to xlate the
+     header, not the compressed data following it.  */
+  if (dest != src)
+    memmove (dest, src, len);
+
+  if (len >= sizeof (Elf32_Chdr))
+    Elf32_cvt_Chdr (dest, src, sizeof (Elf32_Chdr), encode);
+}
+
+static void
+Elf64_cvt_chdr (void *dest, const void *src, size_t len, int encode)
+{
+  if (len == 0)
+    return;
+
+  /* Move everything over, if necessary, we only need to xlate the
+     header, not the compressed data following it.  */
+  if (dest != src)
+    memmove (dest, src, len);
+
+  if (len >= sizeof (Elf64_Chdr))
+    Elf64_cvt_Chdr (dest, src, sizeof (Elf64_Chdr), encode);
+}
diff --git a/libelf/elf32_getchdr.c b/libelf/elf32_getchdr.c
new file mode 100644
index 00000000..982a614c
--- /dev/null
+++ b/libelf/elf32_getchdr.c
@@ -0,0 +1,83 @@
+/* Return section compression header.
+   Copyright (C) 2015 Red Hat, Inc.
+   This file is part of elfutils.
+
+   This file is free software; you can redistribute it and/or modify
+   it under the terms of either
+
+     * the GNU Lesser General Public License as published by the Free
+       Software Foundation; either version 3 of the License, or (at
+       your option) any later version
+
+   or
+
+     * 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
+
+   or both in parallel, as here.
+
+   elfutils 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 copies of the GNU General Public License and
+   the GNU Lesser General Public License along with this program.  If
+   not, see <http://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <libelf.h>
+#include "libelfP.h"
+#include "common.h"
+
+#ifndef LIBELFBITS
+# define LIBELFBITS 32
+#endif
+
+
+ElfW2(LIBELFBITS,Chdr) *
+elfw2(LIBELFBITS,getchdr) (Elf_Scn *scn)
+{
+  ElfW2(LIBELFBITS,Shdr) *shdr = elfw2(LIBELFBITS,getshdr) (scn);
+  if (shdr == NULL)
+    return NULL;
+
+  /* Must have SHF_COMPRESSED flag set.  Allocated or no bits sections
+     can never be compressed.  */
+  if ((shdr->sh_flags & SHF_ALLOC) != 0)
+    {
+      __libelf_seterrno (ELF_E_INVALID_SECTION_FLAGS);
+      return NULL;
+    }
+
+  if (shdr->sh_type == SHT_NULL
+      || shdr->sh_type == SHT_NOBITS)
+    {
+      __libelf_seterrno (ELF_E_INVALID_SECTION_TYPE);
+      return NULL;
+    }
+
+  if ((shdr->sh_flags & SHF_COMPRESSED) == 0)
+    {
+      __libelf_seterrno (ELF_E_NOT_COMPRESSED);
+      return NULL;
+    }
+
+  /* This makes sure the data is in the correct format, so we don't
+     need to swap fields. */
+  Elf_Data *d  = elf_getdata (scn, NULL);
+  if (d == NULL)
+    return NULL;
+
+  if (d->d_size < sizeof (ElfW2(LIBELFBITS,Chdr)) || d->d_buf == NULL)
+    {
+      __libelf_seterrno (ELF_E_INVALID_DATA);
+      return NULL;
+    }
+
+  return (ElfW2(LIBELFBITS,Chdr) *) d->d_buf;
+}
diff --git a/libelf/elf32_getshdr.c b/libelf/elf32_getshdr.c
index 3a6375c1..237d9122 100644
--- a/libelf/elf32_getshdr.c
+++ b/libelf/elf32_getshdr.c
@@ -99,6 +99,7 @@ load_shdr_wrlock (Elf_Scn *scn)
 
       assert ((elf->flags & ELF_F_MALLOCED)
 	      || ehdr->e_ident[EI_DATA] != MY_ELFDATA
+	      || elf->cmd == ELF_C_READ_MMAP
 	      || (! ALLOW_UNALIGNED
 		  && ((uintptr_t) file_shdr
 		      & (__alignof__ (ElfW2(LIBELFBITS,Shdr)) - 1)) != 0));
@@ -106,7 +107,9 @@ load_shdr_wrlock (Elf_Scn *scn)
       /* Now copy the data and at the same time convert the byte order.  */
       if (ehdr->e_ident[EI_DATA] == MY_ELFDATA)
 	{
-	  assert ((elf->flags & ELF_F_MALLOCED) || ! ALLOW_UNALIGNED);
+	  assert ((elf->flags & ELF_F_MALLOCED)
+		  || elf->cmd == ELF_C_READ_MMAP
+		  || ! ALLOW_UNALIGNED);
 	  memcpy (shdr, file_shdr, size);
 	}
       else
diff --git a/libelf/elf32_updatenull.c b/libelf/elf32_updatenull.c
index d3754d32..03de0321 100644
--- a/libelf/elf32_updatenull.c
+++ b/libelf/elf32_updatenull.c
@@ -382,12 +382,27 @@ __elfw2(LIBELFBITS,updatenull_wrlock) (Elf *elf, int *change_bop, size_t shnum)
 
 	      /* Check that the section size is actually a multiple of
 		 the entry size.  */
-	      if (shdr->sh_entsize != 0
-		  && unlikely (shdr->sh_size % shdr->sh_entsize != 0)
+	      if (shdr->sh_entsize != 0 && shdr->sh_entsize != 1
 		  && (elf->flags & ELF_F_PERMISSIVE) == 0)
 		{
-		  __libelf_seterrno (ELF_E_INVALID_SHENTSIZE);
-		  return -1;
+		  /* For compressed sections check the uncompressed size.  */
+		  ElfW2(LIBELFBITS,Word) sh_size;
+		  if ((shdr->sh_flags & SHF_COMPRESSED) == 0)
+		    sh_size = shdr->sh_size;
+		  else
+		    {
+		      ElfW2(LIBELFBITS,Chdr) *chdr;
+		      chdr = elfw2(LIBELFBITS,getchdr) (scn);
+		      if (unlikely (chdr == NULL))
+			return -1;
+		      sh_size = chdr->ch_size;
+		    }
+
+		  if (unlikely (sh_size % shdr->sh_entsize != 0))
+		    {
+		      __libelf_seterrno (ELF_E_INVALID_SHENTSIZE);
+		      return -1;
+		    }
 		}
 	    }
 
diff --git a/libelf/elf64_getchdr.c b/libelf/elf64_getchdr.c
new file mode 100644
index 00000000..6588b791
--- /dev/null
+++ b/libelf/elf64_getchdr.c
@@ -0,0 +1,30 @@
+/* Return section compression header.
+   Copyright (C) 2015 Red Hat, Inc.
+   This file is part of elfutils.
+
+   This file is free software; you can redistribute it and/or modify
+   it under the terms of either
+
+     * the GNU Lesser General Public License as published by the Free
+       Software Foundation; either version 3 of the License, or (at
+       your option) any later version
+
+   or
+
+     * 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
+
+   or both in parallel, as here.
+
+   elfutils 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 copies of the GNU General Public License and
+   the GNU Lesser General Public License along with this program.  If
+   not, see <http://www.gnu.org/licenses/>.  */
+
+#define LIBELFBITS 64
+#include "elf32_getchdr.c"
diff --git a/libelf/elf_begin.c b/libelf/elf_begin.c
index d2920c4e..147f5f4b 100644
--- a/libelf/elf_begin.c
+++ b/libelf/elf_begin.c
@@ -340,6 +340,7 @@ file_read_elf (int fildes, void *map_address, unsigned char *e_ident,
 
       Elf32_Off e_shoff = elf->state.elf32.ehdr->e_shoff;
       if (map_address != NULL && e_ident[EI_DATA] == MY_ELFDATA
+	  && cmd != ELF_C_READ_MMAP /* We need a copy to be able to write.  */
 	  && (ALLOW_UNALIGNED
 	      || (((uintptr_t) ((char *) ehdr + e_shoff)
 		   & (__alignof__ (Elf32_Shdr) - 1)) == 0)))
@@ -441,6 +442,7 @@ file_read_elf (int fildes, void *map_address, unsigned char *e_ident,
 
       Elf64_Off e_shoff = elf->state.elf64.ehdr->e_shoff;
       if (map_address != NULL && e_ident[EI_DATA] == MY_ELFDATA
+	  && cmd != ELF_C_READ_MMAP /* We need a copy to be able to write.  */
 	  && (ALLOW_UNALIGNED
 	      || (((uintptr_t) ((char *) ehdr + e_shoff)
 		   & (__alignof__ (Elf64_Shdr) - 1)) == 0)))
diff --git a/libelf/elf_compress.c b/libelf/elf_compress.c
new file mode 100644
index 00000000..4c7c35e1
--- /dev/null
+++ b/libelf/elf_compress.c
@@ -0,0 +1,516 @@
+/* Compress or decompress a section.
+   Copyright (C) 2015 Red Hat, Inc.
+   This file is part of elfutils.
+
+   This file is free software; you can redistribute it and/or modify
+   it under the terms of either
+
+     * the GNU Lesser General Public License as published by the Free
+       Software Foundation; either version 3 of the License, or (at
+       your option) any later version
+
+   or
+
+     * 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
+
+   or both in parallel, as here.
+
+   elfutils 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 copies of the GNU General Public License and
+   the GNU Lesser General Public License along with this program.  If
+   not, see <http://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <libelf.h>
+#include "libelfP.h"
+#include "common.h"
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/param.h>
+#include <unistd.h>
+#include <zlib.h>
+
+#ifndef MAX
+# define MAX(a, b) ((a) > (b) ? (a) : (b))
+#endif
+
+/* Cleanup and return result.  Don't leak memory.  */
+static void *
+do_deflate_cleanup (void *result, z_stream *z, void *out_buf,
+                    int ei_data, Elf_Data *cdatap)
+{
+  deflateEnd (z);
+  free (out_buf);
+  if (ei_data != MY_ELFDATA)
+    free (cdatap->d_buf);
+  return result;
+}
+
+#define deflate_cleanup(result) \
+    do_deflate_cleanup(result, &z, out_buf, ei_data, &cdata)
+
+/* Given a section, uses the (in-memory) Elf_Data to extract the
+   original data size (including the given header size) and data
+   alignment.  Returns a buffer that has at least hsize bytes (for the
+   caller to fill in with a header) plus zlib compressed date.  Also
+   returns the new buffer size in new_size (hsize + compressed data
+   size).  Returns (void *) -1 when FORCE is false and the compressed
+   data would be bigger than the original data.  */
+void *
+internal_function
+__libelf_compress (Elf_Scn *scn, size_t hsize, int ei_data,
+		   size_t *orig_size, size_t *orig_addralign,
+		   size_t *new_size, bool force)
+{
+  /* The compressed data is the on-disk data.  We simplify the
+     implementation a bit by asking for the (converted) in-memory
+     data (which might be all there is if the user created it with
+     elf_newdata) and then convert back to raw if needed before
+     compressing.  Should be made a bit more clever to directly
+     use raw if that is directly available.  */
+  Elf_Data *data = elf_getdata (scn, NULL);
+  if (data == NULL)
+    return NULL;
+
+  /* When not forced and we immediately know we would use more data by
+     compressing, because of the header plus zlib overhead (five bytes
+     per 16 KB block, plus a one-time overhead of six bytes for the
+     entire stream), don't do anything.  */
+  Elf_Data *next_data = elf_getdata (scn, data);
+  if (next_data == NULL && !force
+      && data->d_size <= hsize + 5 + 6)
+    return (void *) -1;
+
+  *orig_addralign = data->d_align;
+  *orig_size = data->d_size;
+
+  /* Guess an output block size. 1/8th of the original Elf_Data plus
+     hsize.  Make the first chunk twice that size (25%), then increase
+     by a block (12.5%) when necessary.  */
+  size_t block = (data->d_size / 8) + hsize;
+  size_t out_size = 2 * block;
+  void *out_buf = malloc (out_size);
+  if (out_buf == NULL)
+    {
+      __libelf_seterrno (ELF_E_NOMEM);
+      return NULL;
+    }
+
+  /* Caller gets to fill in the header at the start.  Just skip it here.  */
+  size_t used = hsize;
+
+  z_stream z;
+  z.zalloc = Z_NULL;
+  z.zfree = Z_NULL;
+  z.opaque = Z_NULL;
+  int zrc = deflateInit (&z, Z_BEST_COMPRESSION);
+  if (zrc != Z_OK)
+    {
+      __libelf_seterrno (ELF_E_COMPRESS_ERROR);
+      return NULL;
+    }
+
+  Elf_Data cdata;
+  cdata.d_buf = NULL;
+
+  /* Loop over data buffers.  */
+  int flush = Z_NO_FLUSH;
+  do
+    {
+      /* Convert to raw if different endianess.  */
+      cdata = *data;
+      if (ei_data != MY_ELFDATA)
+	{
+	  /* Don't do this conversion in place, we might want to keep
+	     the original data around, caller decides.  */
+	  cdata.d_buf = malloc (data->d_size);
+	  if (cdata.d_buf == NULL)
+	    {
+	      __libelf_seterrno (ELF_E_NOMEM);
+	      return deflate_cleanup (NULL);
+	    }
+	  if (gelf_xlatetof (scn->elf, &cdata, data, ei_data) == NULL)
+	    return deflate_cleanup (NULL);
+	}
+
+      z.avail_in = cdata.d_size;
+      z.next_in = cdata.d_buf;
+
+      /* Get next buffer to see if this is the last one.  */
+      data = next_data;
+      if (data != NULL)
+	{
+	  *orig_addralign = MAX (*orig_addralign, data->d_align);
+	  *orig_size += data->d_size;
+	  next_data = elf_getdata (scn, data);
+	}
+      else
+	flush = Z_FINISH;
+
+      /* Flush one data buffer.  */
+      do
+	{
+	  z.avail_out = out_size - used;
+	  z.next_out = out_buf + used;
+	  zrc = deflate (&z, flush);
+	  if (zrc == Z_STREAM_ERROR)
+	    {
+	      __libelf_seterrno (ELF_E_COMPRESS_ERROR);
+	      return deflate_cleanup (NULL);
+	    }
+	  used += (out_size - used) - z.avail_out;
+
+	  /* Bail out if we are sure the user doesn't want the
+	     compression forced and we are using more compressed data
+	     than original data.  */
+	  if (!force && flush == Z_FINISH && used >= *orig_size)
+	    return deflate_cleanup ((void *) -1);
+
+	  if (z.avail_out == 0)
+	    {
+	      void *bigger = realloc (out_buf, out_size + block);
+	      if (bigger == NULL)
+		{
+		  __libelf_seterrno (ELF_E_NOMEM);
+		  return deflate_cleanup (NULL);
+		}
+	      out_buf = bigger;
+	      out_size += block;
+	    }
+	}
+      while (z.avail_out == 0); /* Need more output buffer.  */
+
+      if (ei_data != MY_ELFDATA)
+	{
+	  free (cdata.d_buf);
+	  cdata.d_buf = NULL;
+	}
+    }
+  while (flush != Z_FINISH); /* More data blocks.  */
+
+  zrc = deflateEnd (&z);
+  if (zrc != Z_OK)
+    {
+      __libelf_seterrno (ELF_E_COMPRESS_ERROR);
+      return deflate_cleanup (NULL);
+    }
+
+  *new_size = used;
+  return out_buf;
+}
+
+void *
+internal_function
+__libelf_decompress (void *buf_in, size_t size_in, size_t size_out)
+{
+  void *buf_out = malloc (size_out);
+  if (unlikely (buf_out == NULL))
+    {
+      __libelf_seterrno (ELF_E_NOMEM);
+      return NULL;
+    }
+
+  z_stream z =
+    {
+      .next_in = buf_in,
+      .avail_in = size_in,
+      .next_out = buf_out,
+      .avail_out = size_out
+    };
+  int zrc = inflateInit (&z);
+  while (z.avail_in > 0 && likely (zrc == Z_OK))
+    {
+      z.next_out = buf_out + (size_out - z.avail_out);
+      zrc = inflate (&z, Z_FINISH);
+      if (unlikely (zrc != Z_STREAM_END))
+	{
+	  zrc = Z_DATA_ERROR;
+	  break;
+	}
+      zrc = inflateReset (&z);
+    }
+  if (likely (zrc == Z_OK))
+    zrc = inflateEnd (&z);
+
+  if (unlikely (zrc != Z_OK) || unlikely (z.avail_out != 0))
+    {
+      free (buf_out);
+      __libelf_seterrno (ELF_E_DECOMPRESS_ERROR);
+      return NULL;
+    }
+
+  return buf_out;
+}
+
+void *
+internal_function
+__libelf_decompress_elf (Elf_Scn *scn, size_t *size_out, size_t *addralign)
+{
+  GElf_Chdr chdr;
+  if (gelf_getchdr (scn, &chdr) == NULL)
+    return NULL;
+
+  if (chdr.ch_type != ELFCOMPRESS_ZLIB)
+    {
+      __libelf_seterrno (ELF_E_UNKNOWN_COMPRESSION_TYPE);
+      return NULL;
+    }
+
+  if (! powerof2 (chdr.ch_addralign))
+    {
+      __libelf_seterrno (ELF_E_INVALID_ALIGN);
+      return NULL;
+    }
+
+  /* Take the in-memory representation, so we can even handle a
+     section that has just been constructed (maybe it was copied
+     over from some other ELF file first with elf_newdata).  This
+     is slightly inefficient when the raw data needs to be
+     converted since then we'll be converting the whole buffer and
+     not just Chdr.  */
+  Elf_Data *data = elf_getdata (scn, NULL);
+  if (data == NULL)
+    return NULL;
+
+  int elfclass = scn->elf->class;
+  size_t hsize = (elfclass == ELFCLASS32
+		  ? sizeof (Elf32_Chdr) : sizeof (Elf64_Chdr));
+  size_t size_in = data->d_size - hsize;
+  void *buf_in = data->d_buf + hsize;
+  void *buf_out = __libelf_decompress (buf_in, size_in, chdr.ch_size);
+  *size_out = chdr.ch_size;
+  *addralign = chdr.ch_addralign;
+  return buf_out;
+}
+
+void
+internal_function
+__libelf_reset_rawdata (Elf_Scn *scn, void *buf, size_t size, size_t align,
+			Elf_Type type)
+{
+  /* This is the new raw data, replace and possibly free old data.  */
+  scn->rawdata.d.d_off = 0;
+  scn->rawdata.d.d_version = __libelf_version;
+  scn->rawdata.d.d_buf = buf;
+  scn->rawdata.d.d_size = size;
+  scn->rawdata.d.d_align = align;
+  scn->rawdata.d.d_type = type;
+
+  /* Existing existing data is no longer valid.  */
+  scn->data_list_rear = NULL;
+  if (scn->data_base != scn->rawdata_base)
+    free (scn->data_base);
+  scn->data_base = NULL;
+  if (scn->elf->map_address == NULL
+      || scn->rawdata_base == scn->zdata_base)
+    free (scn->rawdata_base);
+
+  scn->rawdata_base = buf;
+}
+
+int
+elf_compress (Elf_Scn *scn, int type, unsigned int flags)
+{
+  if (scn == NULL)
+    return -1;
+
+  if ((flags & ~ELF_CHF_FORCE) != 0)
+    {
+      __libelf_seterrno (ELF_E_INVALID_OPERAND);
+      return -1;
+    }
+
+  bool force = (flags & ELF_CHF_FORCE) != 0;
+
+  Elf *elf = scn->elf;
+  GElf_Ehdr ehdr;
+  if (gelf_getehdr (elf, &ehdr) == NULL)
+    return -1;
+
+  int elfclass = elf->class;
+  int elfdata = ehdr.e_ident[EI_DATA];
+
+  Elf64_Xword sh_flags;
+  Elf64_Word sh_type;
+  Elf64_Xword sh_addralign;
+  if (elfclass == ELFCLASS32)
+    {
+      Elf32_Shdr *shdr = elf32_getshdr (scn);
+      if (shdr == NULL)
+	return -1;
+
+      sh_flags = shdr->sh_flags;
+      sh_type = shdr->sh_type;
+      sh_addralign = shdr->sh_addralign;
+    }
+  else
+    {
+      Elf64_Shdr *shdr = elf64_getshdr (scn);
+      if (shdr == NULL)
+	return -1;
+
+      sh_flags = shdr->sh_flags;
+      sh_type = shdr->sh_type;
+      sh_addralign = shdr->sh_addralign;
+    }
+
+  if ((sh_flags & SHF_ALLOC) != 0)
+    {
+      __libelf_seterrno (ELF_E_INVALID_SECTION_FLAGS);
+      return -1;
+    }
+
+  if (sh_type == SHT_NULL || sh_type == SHT_NOBITS)
+    {
+      __libelf_seterrno (ELF_E_INVALID_SECTION_TYPE);
+      return -1;
+    }
+
+  int compressed = (sh_flags & SHF_COMPRESSED);
+  if (type == ELFCOMPRESS_ZLIB)
+    {
+      /* Compress/Deflate.  */
+      if (compressed == 1)
+	{
+	  __libelf_seterrno (ELF_E_ALREADY_COMPRESSED);
+	  return -1;
+	}
+
+      size_t hsize = (elfclass == ELFCLASS32
+		      ? sizeof (Elf32_Chdr) : sizeof (Elf64_Chdr));
+      size_t orig_size, orig_addralign, new_size;
+      void *out_buf = __libelf_compress (scn, hsize, elfdata,
+					 &orig_size, &orig_addralign,
+					 &new_size, force);
+
+      /* Compression would make section larger, don't change anything.  */
+      if (out_buf == (void *) -1)
+	return 0;
+
+      /* Compression failed, return error.  */
+      if (out_buf == NULL)
+	return -1;
+
+      /* Put the header in front of the data.  */
+      if (elfclass == ELFCLASS32)
+	{
+	  Elf32_Chdr chdr;
+	  chdr.ch_type = ELFCOMPRESS_ZLIB;
+	  chdr.ch_size = orig_size;
+	  chdr.ch_addralign = orig_addralign;
+	  if (elfdata != MY_ELFDATA)
+	    {
+	      CONVERT (chdr.ch_type);
+	      CONVERT (chdr.ch_size);
+	      CONVERT (chdr.ch_addralign);
+	    }
+	  memcpy (out_buf, &chdr, sizeof (Elf32_Chdr));
+	}
+      else
+	{
+	  Elf64_Chdr chdr;
+	  chdr.ch_type = ELFCOMPRESS_ZLIB;
+	  chdr.ch_reserved = 0;
+	  chdr.ch_size = orig_size;
+	  chdr.ch_addralign = sh_addralign;
+	  if (elfdata != MY_ELFDATA)
+	    {
+	      CONVERT (chdr.ch_type);
+	      CONVERT (chdr.ch_reserved);
+	      CONVERT (chdr.ch_size);
+	      CONVERT (chdr.ch_addralign);
+	    }
+	  memcpy (out_buf, &chdr, sizeof (Elf64_Chdr));
+	}
+
+      /* Note we keep the sh_entsize as is, we assume it is setup
+	 correctly and ignored when SHF_COMPRESSED is set.  */
+      if (elfclass == ELFCLASS32)
+	{
+	  Elf32_Shdr *shdr = elf32_getshdr (scn);
+	  shdr->sh_size = new_size;
+	  shdr->sh_addralign = 1;
+	  shdr->sh_flags |= SHF_COMPRESSED;
+	}
+      else
+	{
+	  Elf64_Shdr *shdr = elf64_getshdr (scn);
+	  shdr->sh_size = new_size;
+	  shdr->sh_addralign = 1;
+	  shdr->sh_flags |= SHF_COMPRESSED;
+	}
+
+      __libelf_reset_rawdata (scn, out_buf, new_size, 1, ELF_T_CHDR);
+
+      /* The section is now compressed, we could keep the uncompressed
+	 data around, but since that might have been multiple Elf_Data
+	 buffers let the user uncompress it explicitly again if they
+	 want it to simplify bookkeeping.  */
+      scn->zdata_base = NULL;
+
+      return 1;
+    }
+  else if (type == 0)
+    {
+      /* Decompress/Inflate.  */
+      if (compressed == 0)
+	{
+	  __libelf_seterrno (ELF_E_NOT_COMPRESSED);
+	  return -1;
+	}
+
+      /* If the data is already decompressed (by elf_strptr), then we
+	 only need to setup the rawdata and section header. XXX what
+	 about elf_newdata?  */
+      if (scn->zdata_base == NULL)
+	{
+	  size_t size_out, addralign;
+	  void *buf_out = __libelf_decompress_elf (scn, &size_out, &addralign);
+	  if (buf_out == NULL)
+	    return -1;
+
+	  scn->zdata_base = buf_out;
+	  scn->zdata_size = size_out;
+	  scn->zdata_align = addralign;
+	}
+
+      /* Note we keep the sh_entsize as is, we assume it is setup
+	 correctly and ignored when SHF_COMPRESSED is set.  */
+      if (elfclass == ELFCLASS32)
+	{
+	  Elf32_Shdr *shdr = elf32_getshdr (scn);
+	  shdr->sh_size = scn->zdata_size;
+	  shdr->sh_addralign = scn->zdata_align;
+	  shdr->sh_flags &= ~SHF_COMPRESSED;
+	}
+      else
+	{
+	  Elf64_Shdr *shdr = elf64_getshdr (scn);
+	  shdr->sh_size = scn->zdata_size;
+	  shdr->sh_addralign = scn->zdata_align;
+	  shdr->sh_flags &= ~SHF_COMPRESSED;
+	}
+
+      __libelf_reset_rawdata (scn, scn->zdata_base,
+			      scn->zdata_size, scn->zdata_align,
+			      __libelf_data_type (elf, sh_type));
+
+      return 1;
+    }
+  else
+    {
+      __libelf_seterrno (ELF_E_UNKNOWN_COMPRESSION_TYPE);
+      return -1;
+    }
+}
diff --git a/libelf/elf_compress_gnu.c b/libelf/elf_compress_gnu.c
new file mode 100644
index 00000000..c35dc395
--- /dev/null
+++ b/libelf/elf_compress_gnu.c
@@ -0,0 +1,208 @@
+/* Compress or decompress a section.
+   Copyright (C) 2015 Red Hat, Inc.
+   This file is part of elfutils.
+
+   This file is free software; you can redistribute it and/or modify
+   it under the terms of either
+
+     * the GNU Lesser General Public License as published by the Free
+       Software Foundation; either version 3 of the License, or (at
+       your option) any later version
+
+   or
+
+     * 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
+
+   or both in parallel, as here.
+
+   elfutils 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 copies of the GNU General Public License and
+   the GNU Lesser General Public License along with this program.  If
+   not, see <http://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <libelf.h>
+#include "libelfP.h"
+#include "common.h"
+
+int
+elf_compress_gnu (Elf_Scn *scn, int inflate, unsigned int flags)
+{
+  if (scn == NULL)
+    return -1;
+
+  if ((flags & ~ELF_CHF_FORCE) != 0)
+    {
+      __libelf_seterrno (ELF_E_INVALID_OPERAND);
+      return -1;
+    }
+
+  bool force = (flags & ELF_CHF_FORCE) != 0;
+
+  Elf *elf = scn->elf;
+  GElf_Ehdr ehdr;
+  if (gelf_getehdr (elf, &ehdr) == NULL)
+    return -1;
+
+  int elfclass = elf->class;
+  int elfdata = ehdr.e_ident[EI_DATA];
+
+  Elf64_Xword sh_flags;
+  Elf64_Word sh_type;
+  Elf64_Xword sh_addralign;
+  if (elfclass == ELFCLASS32)
+    {
+      Elf32_Shdr *shdr = elf32_getshdr (scn);
+      if (shdr == NULL)
+	return -1;
+
+      sh_flags = shdr->sh_flags;
+      sh_type = shdr->sh_type;
+      sh_addralign = shdr->sh_addralign;
+    }
+  else
+    {
+      Elf64_Shdr *shdr = elf64_getshdr (scn);
+      if (shdr == NULL)
+	return -1;
+
+      sh_flags = shdr->sh_flags;
+      sh_type = shdr->sh_type;
+      sh_addralign = shdr->sh_addralign;
+    }
+
+  if ((sh_flags & SHF_ALLOC) != 0)
+    {
+      __libelf_seterrno (ELF_E_INVALID_SECTION_FLAGS);
+      return -1;
+    }
+
+  if (sh_type == SHT_NULL || sh_type == SHT_NOBITS)
+    {
+      __libelf_seterrno (ELF_E_INVALID_SECTION_TYPE);
+      return -1;
+    }
+
+  /* For GNU compression we cannot really know whether the section is
+     already compressed or not.  Just try and see what happens...  */
+  // int compressed = (sh_flags & SHF_COMPRESSED);
+  if (inflate == 1)
+    {
+      size_t hsize = 4 + 8; /* GNU "ZLIB" + 8 byte size.  */
+      size_t orig_size, new_size, orig_addralign;
+      void *out_buf = __libelf_compress (scn, hsize, elfdata,
+					 &orig_size, &orig_addralign,
+					 &new_size, force);
+
+      /* Compression would make section larger, don't change anything.  */
+      if (out_buf == (void *) -1)
+	return 0;
+
+      /* Compression failed, return error.  */
+      if (out_buf == NULL)
+	return -1;
+
+      uint64_t be64_size = htobe64 (orig_size);
+      memmove (out_buf, "ZLIB", 4);
+      memmove (out_buf + 4, &be64_size, sizeof (be64_size));
+
+      /* We don't know anything about sh_entsize, sh_addralign and
+	 sh_flags won't have a SHF_COMPRESSED hint in the GNU format.
+	 Just adjust the sh_size.  */
+      if (elfclass == ELFCLASS32)
+	{
+	  Elf32_Shdr *shdr = elf32_getshdr (scn);
+	  shdr->sh_size = new_size;
+	}
+      else
+	{
+	  Elf64_Shdr *shdr = elf64_getshdr (scn);
+	  shdr->sh_size = new_size;
+	}
+
+      __libelf_reset_rawdata (scn, out_buf, new_size, 1, ELF_T_BYTE);
+
+      /* The section is now compressed, we could keep the uncompressed
+	 data around, but since that might have been multiple Elf_Data
+	 buffers let the user uncompress it explicitly again if they
+	 want it to simplify bookkeeping.  */
+      scn->zdata_base = NULL;
+
+      return 1;
+    }
+  else if (inflate == 0)
+    {
+      /* In theory the user could have constucted a compressed section
+	 by hand.  But we always just take the rawdata directly and
+	 decompress that.  */
+      Elf_Data *data = elf_rawdata (scn, NULL);
+      if (data == NULL)
+	return -1;
+
+      size_t hsize = 4 + 8; /* GNU "ZLIB" + 8 byte size.  */
+      if (data->d_size < hsize || memcmp (data->d_buf, "ZLIB", 4) != 0)
+	{
+          __libelf_seterrno (ELF_E_NOT_COMPRESSED);
+	  return -1;
+	}
+
+      /* There is a 12-byte header of "ZLIB" followed by
+	 an 8-byte big-endian size.  There is only one type and
+	 Alignment isn't preserved separately.  */
+      uint64_t gsize;
+      memcpy (&gsize, data->d_buf + 4, sizeof gsize);
+      gsize = be64toh (gsize);
+
+      /* One more sanity check, size should be bigger than original
+	 data size plus some overhead (4 chars ZLIB + 8 bytes size + 6
+	 bytes zlib stream overhead + 5 bytes overhead max for one 16K
+	 block) and should fit into a size_t.  */
+      if (gsize + 4 + 8 + 6 + 5 < data->d_size || gsize > SIZE_MAX)
+	{
+	  __libelf_seterrno (ELF_E_NOT_COMPRESSED);
+	  return -1;
+	}
+
+      size_t size = gsize;
+      size_t size_in = data->d_size - hsize;
+      void *buf_in = data->d_buf + hsize;
+      void *buf_out = __libelf_decompress (buf_in, size_in, size);
+      if (buf_out == NULL)
+	return -1;
+
+      /* We don't know anything about sh_entsize, sh_addralign and
+	 sh_flags won't have a SHF_COMPRESSED hint in the GNU format.
+	 Just adjust the sh_size.  */
+      if (elfclass == ELFCLASS32)
+	{
+	  Elf32_Shdr *shdr = elf32_getshdr (scn);
+	  shdr->sh_size = size;
+	}
+      else
+	{
+	  Elf64_Shdr *shdr = elf64_getshdr (scn);
+	  shdr->sh_size = size;
+	}
+
+      __libelf_reset_rawdata (scn, buf_out, size, sh_addralign,
+			      __libelf_data_type (elf, sh_type));
+
+      scn->zdata_base = buf_out;
+
+      return 1;
+    }
+  else
+    {
+      __libelf_seterrno (ELF_E_UNKNOWN_COMPRESSION_TYPE);
+      return -1;
+    }
+}
diff --git a/libelf/elf_end.c b/libelf/elf_end.c
index 7ea876c3..fde17b50 100644
--- a/libelf/elf_end.c
+++ b/libelf/elf_end.c
@@ -150,6 +150,12 @@ elf_end (Elf *elf)
 		  /* It doesn't matter which pointer.  */
 		  free (scn->shdr.e32);
 
+		/* Free zdata if uncompressed, but not yet used as
+		   rawdata_base.  If it is already used it will be
+		   freed below.  */
+		if (scn->zdata_base != scn->rawdata_base)
+		  free (scn->zdata_base);
+
 		/* If the file has the same byte order and the
 		   architecture doesn't require overly stringent
 		   alignment the raw data buffer is the same as the
@@ -158,8 +164,9 @@ elf_end (Elf *elf)
 		  free (scn->data_base);
 
 		/* The section data is allocated if we couldn't mmap
-		   the file.  */
-		if (elf->map_address == NULL)
+		   the file.  Or if we had to decompress.  */
+		if (elf->map_address == NULL
+		    || scn->rawdata_base == scn->zdata_base)
 		  free (scn->rawdata_base);
 
 		/* Free the list of data buffers for the section.
diff --git a/libelf/elf_error.c b/libelf/elf_error.c
index d6bdaab0..888b389a 100644
--- a/libelf/elf_error.c
+++ b/libelf/elf_error.c
@@ -230,6 +230,41 @@ core files")
   (ELF_E_NO_PHDR_IDX \
    + sizeof "file has no program header")
   N_("invalid offset")
+  "\0"
+#define ELF_E_INVALID_SECTION_TYPE_IDX \
+  (ELF_E_INVALID_OFFSET_IDX \
+   + sizeof "invalid offset")
+  N_("invalid section type")
+  "\0"
+#define ELF_E_INVALID_SECTION_FLAGS_IDX \
+  (ELF_E_INVALID_SECTION_TYPE_IDX \
+   + sizeof "invalid section type")
+  N_("invalid section flags")
+  "\0"
+#define ELF_E_NOT_COMPRESSED_IDX		\
+  (ELF_E_INVALID_SECTION_FLAGS_IDX			\
+   + sizeof "invalid section flags")
+  N_("section does not contain compressed data")
+  "\0"
+#define ELF_E_ALREADY_COMPRESSED_IDX \
+  (ELF_E_NOT_COMPRESSED_IDX \
+   + sizeof "section does not contain compressed data")
+  N_("section contains compressed data")
+  "\0"
+#define ELF_E_UNKNOWN_COMPRESSION_TYPE_IDX \
+  (ELF_E_ALREADY_COMPRESSED_IDX \
+   + sizeof "section contains compressed data")
+  N_("unknown compression type")
+  "\0"
+#define ELF_E_COMPRESS_ERROR_IDX \
+  (ELF_E_UNKNOWN_COMPRESSION_TYPE_IDX \
+   + sizeof "unknown compression type")
+  N_("cannot compress data")
+  "\0"
+#define ELF_E_DECOMPRESS_ERROR_IDX \
+  (ELF_E_COMPRESS_ERROR_IDX \
+   + sizeof "cannot compress data")
+  N_("cannot decompress data")
 };
 
 
@@ -277,7 +312,14 @@ static const uint_fast16_t msgidx[ELF_E_NUM] =
   [ELF_E_GROUP_NOT_REL] = ELF_E_GROUP_NOT_REL_IDX,
   [ELF_E_INVALID_PHDR] = ELF_E_INVALID_PHDR_IDX,
   [ELF_E_NO_PHDR] = ELF_E_NO_PHDR_IDX,
-  [ELF_E_INVALID_OFFSET] = ELF_E_INVALID_OFFSET_IDX
+  [ELF_E_INVALID_OFFSET] = ELF_E_INVALID_OFFSET_IDX,
+  [ELF_E_INVALID_SECTION_TYPE] = ELF_E_INVALID_SECTION_TYPE_IDX,
+  [ELF_E_INVALID_SECTION_FLAGS] = ELF_E_INVALID_SECTION_FLAGS_IDX,
+  [ELF_E_NOT_COMPRESSED] = ELF_E_NOT_COMPRESSED_IDX,
+  [ELF_E_ALREADY_COMPRESSED] = ELF_E_ALREADY_COMPRESSED_IDX,
+  [ELF_E_UNKNOWN_COMPRESSION_TYPE] = ELF_E_UNKNOWN_COMPRESSION_TYPE_IDX,
+  [ELF_E_COMPRESS_ERROR] = ELF_E_COMPRESS_ERROR_IDX,
+  [ELF_E_DECOMPRESS_ERROR] = ELF_E_DECOMPRESS_ERROR_IDX
 };
 #define nmsgidx ((int) (sizeof (msgidx) / sizeof (msgidx[0])))
 
diff --git a/libelf/elf_getdata.c b/libelf/elf_getdata.c
index 9a567e51..4ec94b98 100644
--- a/libelf/elf_getdata.c
+++ b/libelf/elf_getdata.c
@@ -106,6 +106,7 @@ const uint_fast8_t __libelf_type_aligns[EV_NUM - 1][ELFCLASSNUM - 1][ELF_T_NUM]
       [ELF_T_NHDR] = __alignof__ (ElfW2(Bits,Nhdr)),			      \
       [ELF_T_GNUHASH] = __alignof__ (Elf32_Word),			      \
       [ELF_T_AUXV] = __alignof__ (ElfW2(Bits,auxv_t)),			      \
+      [ELF_T_CHDR] = __alignof__ (ElfW2(Bits,Chdr)),			      \
     }
     [EV_CURRENT - 1] =
     {
@@ -117,6 +118,22 @@ const uint_fast8_t __libelf_type_aligns[EV_NUM - 1][ELFCLASSNUM - 1][ELF_T_NUM]
 #endif
 
 
+Elf_Type
+internal_function
+__libelf_data_type (Elf *elf, int sh_type)
+{
+  /* Some broken ELF ABI for 64-bit machines use the wrong hash table
+     entry size.  See elf-knowledge.h for more information.  */
+  if (sh_type == SHT_HASH && elf->class == ELFCLASS64)
+    {
+      GElf_Ehdr ehdr_mem;
+      GElf_Ehdr *ehdr = __gelf_getehdr_rdlock (elf, &ehdr_mem);
+      return (SH_ENTSIZE_HASH (ehdr) == 4 ? ELF_T_WORD : ELF_T_XWORD);
+    }
+  else
+    return shtype_map[LIBELF_EV_IDX][TYPEIDX (sh_type)];
+}
+
 /* Convert the data in the current section.  */
 static void
 convert_data (Elf_Scn *scn, int version __attribute__ ((unused)), int eclass,
@@ -204,6 +221,7 @@ __libelf_set_rawdata_wrlock (Elf_Scn *scn)
   Elf64_Off offset;
   Elf64_Xword size;
   Elf64_Xword align;
+  Elf64_Xword flags;
   int type;
   Elf *elf = scn->elf;
 
@@ -220,6 +238,7 @@ __libelf_set_rawdata_wrlock (Elf_Scn *scn)
       size = shdr->sh_size;
       type = shdr->sh_type;
       align = shdr->sh_addralign;
+      flags = shdr->sh_flags;
     }
   else
     {
@@ -234,6 +253,7 @@ __libelf_set_rawdata_wrlock (Elf_Scn *scn)
       size = shdr->sh_size;
       type = shdr->sh_type;
       align = shdr->sh_addralign;
+      flags = shdr->sh_flags;
     }
 
   /* If the section has no data (for whatever reason), leave the `d_buf'
@@ -243,7 +263,10 @@ __libelf_set_rawdata_wrlock (Elf_Scn *scn)
       /* First a test whether the section is valid at all.  */
       size_t entsize;
 
-      if (type == SHT_HASH)
+      /* Compressed data has a header, but then compressed data.  */
+      if ((flags & SHF_COMPRESSED) != 0)
+	entsize = 1;
+      else if (type == SHT_HASH)
 	{
 	  GElf_Ehdr ehdr_mem;
 	  GElf_Ehdr *ehdr = __gelf_getehdr_rdlock (elf, &ehdr_mem);
@@ -320,17 +343,13 @@ __libelf_set_rawdata_wrlock (Elf_Scn *scn)
     }
 
   scn->rawdata.d.d_size = size;
-  /* Some broken ELF ABI for 64-bit machines use the wrong hash table
-     entry size.  See elf-knowledge.h for more information.  */
-  if (type == SHT_HASH && elf->class == ELFCLASS64)
-    {
-      GElf_Ehdr ehdr_mem;
-      GElf_Ehdr *ehdr = __gelf_getehdr_rdlock (elf, &ehdr_mem);
-      scn->rawdata.d.d_type
-	= (SH_ENTSIZE_HASH (ehdr) == 4 ? ELF_T_WORD : ELF_T_XWORD);
-    }
+
+  /* Compressed data always has type ELF_T_CHDR regardless of the
+     section type.  */
+  if ((flags & SHF_COMPRESSED) != 0)
+    scn->rawdata.d.d_type = ELF_T_CHDR;
   else
-    scn->rawdata.d.d_type = shtype_map[LIBELF_EV_IDX][TYPEIDX (type)];
+    scn->rawdata.d.d_type = __libelf_data_type (elf, type);
   scn->rawdata.d.d_off = 0;
 
   /* Make sure the alignment makes sense.  d_align should be aligned both
diff --git a/libelf/elf_strptr.c b/libelf/elf_strptr.c
index c5138dc6..ea210459 100644
--- a/libelf/elf_strptr.c
+++ b/libelf/elf_strptr.c
@@ -37,6 +37,21 @@
 #include "libelfP.h"
 
 
+static void *
+get_zdata (Elf_Scn *strscn)
+{
+  size_t zsize, zalign;
+  void *zdata = __libelf_decompress_elf (strscn, &zsize, &zalign);
+  if (zdata == NULL)
+    return NULL;
+
+  strscn->zdata_base = zdata;
+  strscn->zdata_size = zsize;
+  strscn->zdata_align = zalign;
+
+  return zdata;
+}
+
 char *
 elf_strptr (Elf *elf, size_t idx, size_t offset)
 {
@@ -94,8 +109,16 @@ elf_strptr (Elf *elf, size_t idx, size_t offset)
 	  goto out;
 	}
 
-      sh_size = shdr->sh_size;
-      if (unlikely (offset >= shdr->sh_size))
+      if ((shdr->sh_flags & SHF_COMPRESSED) == 0)
+	sh_size = shdr->sh_size;
+      else
+	{
+	  if (strscn->zdata_base == NULL && get_zdata (strscn) == NULL)
+	    goto out;
+	  sh_size = strscn->zdata_size;
+	}
+
+      if (unlikely (offset >= sh_size))
 	{
 	  /* The given offset is too big, it is beyond this section.  */
 	  __libelf_seterrno (ELF_E_OFFSET_RANGE);
@@ -112,8 +135,16 @@ elf_strptr (Elf *elf, size_t idx, size_t offset)
 	  goto out;
 	}
 
-      sh_size = shdr->sh_size;
-      if (unlikely (offset >= shdr->sh_size))
+      if ((shdr->sh_flags & SHF_COMPRESSED) == 0)
+	sh_size = shdr->sh_size;
+      else
+	{
+	  if (strscn->zdata_base == NULL && get_zdata (strscn) == NULL)
+	    goto out;
+	  sh_size = strscn->zdata_size;
+	}
+
+      if (unlikely (offset >= sh_size))
 	{
 	  /* The given offset is too big, it is beyond this section.  */
 	  __libelf_seterrno (ELF_E_OFFSET_RANGE);
@@ -131,7 +162,17 @@ elf_strptr (Elf *elf, size_t idx, size_t offset)
 	goto out;
     }
 
-  if (likely (strscn->data_list_rear == NULL))
+  if (unlikely (strscn->zdata_base != NULL))
+    {
+      /* Make sure the string is NUL terminated.  Start from the end,
+         which very likely is a NUL char.  */
+      if (likely (memrchr (&strscn->zdata_base[offset],
+			   '\0', sh_size - offset) != NULL))
+        result = &strscn->zdata_base[offset];
+      else
+        __libelf_seterrno (ELF_E_INVALID_INDEX);
+    }
+  else if (likely (strscn->data_list_rear == NULL))
     {
       // XXX The above is currently correct since elf_newdata will
       // make sure to convert the rawdata into the datalist if
diff --git a/libelf/exttypes.h b/libelf/exttypes.h
index 8cb2aaec..7bacd654 100644
--- a/libelf/exttypes.h
+++ b/libelf/exttypes.h
@@ -1,5 +1,5 @@
 /* External ELF types.
-   Copyright (C) 1998-2010 Red Hat, Inc.
+   Copyright (C) 1998-2010, 2015 Red Hat, Inc.
    This file is part of elfutils.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 1998.
 
@@ -75,6 +75,7 @@ Syminfo32 (Ext_);
 Move32 (Ext_);
 Lib32 (Ext_);
 auxv_t32 (Ext_);
+Chdr32 (Ext_);
 
 Ehdr64 (Ext_);
 Phdr64 (Ext_);
@@ -92,6 +93,7 @@ Syminfo64 (Ext_);
 Move64 (Ext_);
 Lib64 (Ext_);
 auxv_t64 (Ext_);
+Chdr64 (Ext_);
 
 #undef START
 #undef END
diff --git a/libelf/gelf.h b/libelf/gelf.h
index e3f07404..1bc7ee72 100644
--- a/libelf/gelf.h
+++ b/libelf/gelf.h
@@ -1,5 +1,5 @@
 /* This file defines generic ELF types, structures, and macros.
-   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2007 Red Hat, Inc.
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2007, 2015 Red Hat, Inc.
    This file is part of elfutils.
 
    This file is free software; you can redistribute it and/or modify
@@ -85,6 +85,9 @@ typedef Elf64_Rela GElf_Rela;
 /* Program segment header.  */
 typedef Elf64_Phdr GElf_Phdr;
 
+/* Header of a compressed section.  */
+typedef Elf64_Chdr GElf_Chdr;
+
 /* Dynamic section entry.  */
 typedef Elf64_Dyn GElf_Dyn;
 
@@ -183,6 +186,9 @@ extern int gelf_update_phdr (Elf *__elf, int __ndx, GElf_Phdr *__src);
 /* Create new program header with PHNUM entries.  */
 extern unsigned long int gelf_newphdr (Elf *__elf, size_t __phnum);
 
+/* Get compression header of section if any.  Returns NULL and sets
+   elf_errno if the section isn't compressed or an error occurred.  */
+extern GElf_Chdr *gelf_getchdr (Elf_Scn *__scn, GElf_Chdr *__dst);
 
 /* Convert data structure from the representation in the file represented
    by ELF to their memory representation.  */
diff --git a/libelf/gelf_fsize.c b/libelf/gelf_fsize.c
index a124fa84..0c509265 100644
--- a/libelf/gelf_fsize.c
+++ b/libelf/gelf_fsize.c
@@ -68,6 +68,7 @@ const size_t __libelf_type_sizes[EV_NUM - 1][ELFCLASSNUM - 1][ELF_T_NUM] =
       [ELF_T_MOVE]	= sizeof (ElfW2(LIBELFBITS, Ext_Move)),		      \
       [ELF_T_LIB]	= sizeof (ElfW2(LIBELFBITS, Ext_Lib)),		      \
       [ELF_T_AUXV]	= sizeof (ElfW2(LIBELFBITS, Ext_auxv_t)),	      \
+      [ELF_T_CHDR]	= sizeof (ElfW2(LIBELFBITS, Ext_Chdr)),		      \
       [ELF_T_GNUHASH]	= ELFW2(LIBELFBITS, FSZ_WORD)
       TYPE_SIZES (32)
     },
diff --git a/libelf/gelf_getchdr.c b/libelf/gelf_getchdr.c
new file mode 100644
index 00000000..394bf4b3
--- /dev/null
+++ b/libelf/gelf_getchdr.c
@@ -0,0 +1,69 @@
+/* Return section compression header.
+   Copyright (C) 2015 Red Hat, Inc.
+   This file is part of elfutils.
+
+   This file is free software; you can redistribute it and/or modify
+   it under the terms of either
+
+     * the GNU Lesser General Public License as published by the Free
+       Software Foundation; either version 3 of the License, or (at
+       your option) any later version
+
+   or
+
+     * 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
+
+   or both in parallel, as here.
+
+   elfutils 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 copies of the GNU General Public License and
+   the GNU Lesser General Public License along with this program.  If
+   not, see <http://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "libelfP.h"
+#include <gelf.h>
+#include <stddef.h>
+
+
+GElf_Chdr *
+gelf_getchdr (Elf_Scn *scn, GElf_Chdr *dest)
+{
+  if (scn == NULL)
+    return NULL;
+
+  if (dest == NULL)
+    {
+      __libelf_seterrno (ELF_E_INVALID_OPERAND);
+      return NULL;
+    }
+
+  if (scn->elf->class == ELFCLASS32)
+    {
+      Elf32_Chdr *chdr = elf32_getchdr (scn);
+      if (chdr == NULL)
+	return NULL;
+      dest->ch_type = chdr->ch_type;
+      dest->ch_size = chdr->ch_size;
+      dest->ch_addralign = chdr->ch_addralign;
+    }
+  else
+    {
+      Elf64_Chdr *chdr = elf64_getchdr (scn);
+      if (chdr == NULL)
+	return NULL;
+      *dest = *chdr;
+    }
+
+  return dest;
+}
+INTDEF(gelf_getchdr)
diff --git a/libelf/gelf_xlate.c b/libelf/gelf_xlate.c
index c5805e73..f3d3b7a0 100644
--- a/libelf/gelf_xlate.c
+++ b/libelf/gelf_xlate.c
@@ -166,6 +166,7 @@ union unaligned
 #include "version_xlate.h"
 #include "gnuhash_xlate.h"
 #include "note_xlate.h"
+#include "chdr_xlate.h"
 
 
 /* Now the externally visible table with the function pointers.  */
@@ -198,7 +199,8 @@ const xfct_t __elf_xfctstom[EV_NUM - 1][EV_NUM - 1][ELFCLASSNUM - 1][ELF_T_NUM]
 	[ELF_T_SYMINFO] = ElfW2(Bits, cvt_Syminfo),			      \
 	[ELF_T_MOVE]	= ElfW2(Bits, cvt_Move),			      \
 	[ELF_T_LIB]	= ElfW2(Bits, cvt_Lib),				      \
-	[ELF_T_AUXV]	= ElfW2(Bits, cvt_auxv_t)
+	[ELF_T_AUXV]	= ElfW2(Bits, cvt_auxv_t),			      \
+	[ELF_T_CHDR]	= ElfW2(Bits, cvt_chdr)
         define_xfcts (32),
 	[ELF_T_GNUHASH] = Elf32_cvt_Word
       },
diff --git a/libelf/gelf_xlate.h b/libelf/gelf_xlate.h
index f11eb90b..3c0e4bf6 100644
--- a/libelf/gelf_xlate.h
+++ b/libelf/gelf_xlate.h
@@ -50,6 +50,7 @@ TYPE (Syminfo, LIBELFBITS)
 TYPE (Move, LIBELFBITS)
 TYPE (Lib, LIBELFBITS)
 TYPE (auxv_t, LIBELFBITS)
+TYPE (Chdr, LIBELFBITS)
 
 
 /* Prepare for the next round.  */
diff --git a/libelf/libelf.h b/libelf/libelf.h
index 54f7c29b..c0d6389f 100644
--- a/libelf/libelf.h
+++ b/libelf/libelf.h
@@ -1,5 +1,5 @@
 /* Interface for libelf.
-   Copyright (C) 1998-2010 Red Hat, Inc.
+   Copyright (C) 1998-2010, 2015 Red Hat, Inc.
    This file is part of elfutils.
 
    This file is free software; you can redistribute it and/or modify
@@ -35,6 +35,34 @@
 /* Get the ELF types.  */
 #include <elf.h>
 
+#ifndef SHF_COMPRESSED
+ /* Older glibc elf.h might not yet define the ELF compression types.  */
+ #define SHF_COMPRESSED      (1 << 11)  /* Section with compressed data. */
+
+ /* Section compression header.  Used when SHF_COMPRESSED is set.  */
+
+ typedef struct
+ {
+   Elf32_Word   ch_type;        /* Compression format.  */
+   Elf32_Word   ch_size;        /* Uncompressed data size.  */
+   Elf32_Word   ch_addralign;   /* Uncompressed data alignment.  */
+ } Elf32_Chdr;
+
+ typedef struct
+ {
+   Elf64_Word   ch_type;        /* Compression format.  */
+   Elf64_Word   ch_reserved;
+   Elf64_Xword  ch_size;        /* Uncompressed data size.  */
+   Elf64_Xword  ch_addralign;   /* Uncompressed data alignment.  */
+ } Elf64_Chdr;
+
+ /* Legal values for ch_type (compression algorithm).  */
+ #define ELFCOMPRESS_ZLIB       1          /* ZLIB/DEFLATE algorithm.  */
+ #define ELFCOMPRESS_LOOS       0x60000000 /* Start of OS-specific.  */
+ #define ELFCOMPRESS_HIOS       0x6fffffff /* End of OS-specific.  */
+ #define ELFCOMPRESS_LOPROC     0x70000000 /* Start of processor-specific.  */
+ #define ELFCOMPRESS_HIPROC     0x7fffffff /* End of processor-specific.  */
+#endif
 
 /* Known translation types.  */
 typedef enum
@@ -64,6 +92,7 @@ typedef enum
   ELF_T_LIB,			/* Elf32_Lib, Elf64_Lib, ... */
   ELF_T_GNUHASH,		/* GNU-style hash section.  */
   ELF_T_AUXV,			/* Elf32_auxv_t, Elf64_auxv_t, ... */
+  ELF_T_CHDR,			/* Compressed, Elf32_Chdr, Elf64_Chdr, ... */
   /* Keep this the last entry.  */
   ELF_T_NUM
 } Elf_Type;
@@ -116,6 +145,12 @@ enum
 #define ELF_F_PERMISSIVE	ELF_F_PERMISSIVE
 };
 
+/* Flags for elf_compress[_gnu].  */
+enum
+{
+  ELF_CHF_FORCE = 0x1
+#define ELF_CHF_FORCE ELF_CHF_FORCE
+};
 
 /* Identification values for recognized object files.  */
 typedef enum
@@ -267,6 +302,62 @@ extern Elf32_Shdr *elf32_getshdr (Elf_Scn *__scn);
 /* Similar for ELFCLASS64.  */
 extern Elf64_Shdr *elf64_getshdr (Elf_Scn *__scn);
 
+/* Returns compression header for a section if section data is
+   compressed.  Returns NULL and sets elf_errno if the section isn't
+   compressed or an error occurred.  */
+extern Elf32_Chdr *elf32_getchdr (Elf_Scn *__scn);
+extern Elf64_Chdr *elf64_getchdr (Elf_Scn *__scn);
+
+/* Compress or decompress the data of a section and adjust the section
+   header.
+
+   elf_compress works by setting or clearing the SHF_COMPRESS flag
+   from the section Shdr and will encode or decode a Elf32_Chdr or
+   Elf64_Chdr at the start of the section data.  elf_compress_gnu will
+   encode or decode any section, but is traditionally only used for
+   sections that have a name starting with ".debug" when
+   uncompressed or ".zdebug" when compressed and stores just the
+   uncompressed size.  The GNU compression method is deprecated and
+   should only be used for legacy support.
+
+   elf_compress takes a compression type that should be either zero to
+   decompress or an ELFCOMPRESS algorithm to use for compression.
+   Currently only ELFCOMPRESS_ZLIB is supported.  elf_compress_gnu
+   will compress in the traditional GNU compression format when
+   compress is one and decompress the section data when compress is
+   zero.
+
+   The FLAGS argument can be zero or ELF_CHF_FORCE.  If FLAGS contains
+   ELF_CHF_FORCE then it will always compress the section, even if
+   that would not reduce the size of the data section (including the
+   header).  Otherwise elf_compress and elf_compress_gnu will compress
+   the section only if the total data size is reduced.
+
+   On successful compression or decompression the function returns
+   one.  If (not forced) compression is requested and the data section
+   would not actually reduce in size, the section is not actually
+   compressed and zero is returned.  Otherwise -1 is returned and
+   elf_errno is set.
+
+   It is an error to request compression for a section that already
+   has SHF_COMPRESSED set, or (for elf_compress) to request
+   decompression for an section that doesn't have SHF_COMPRESSED set.
+   It is always an error to call these functions on SHT_NOBITS
+   sections or if the section has the SHF_ALLOC flag set.
+   elf_compress_gnu will not check whether the section name starts
+   with ".debug" or .zdebug".  It is the responsibilty of the caller
+   to make sure the deprecated GNU compression method is only called
+   on correctly named sections (and to change the name of the section
+   when using elf_compress_gnu).
+
+   All previous returned Shdrs and Elf_Data buffers are invalidated by
+   this call and should no longer be accessed.
+
+   Note that although this changes the header and data returned it
+   doesn't mark the section as dirty.  To keep the changes when
+   calling elf_update the section has to be flagged ELF_F_DIRTY.  */
+extern int elf_compress (Elf_Scn *scn, int type, unsigned int flags);
+extern int elf_compress_gnu (Elf_Scn *scn, int compress, unsigned int flags);
 
 /* Set or clear flags for ELF file.  */
 extern unsigned int elf_flagelf (Elf *__elf, Elf_Cmd __cmd,
@@ -288,8 +379,11 @@ extern unsigned int elf_flagshdr (Elf_Scn *__scn, Elf_Cmd __cmd,
 				  unsigned int __flags);
 
 
-/* Get data from section while translating from file representation
-   to memory representation.  */
+/* Get data from section while translating from file representation to
+   memory representation.  The Elf_Data d_type is set based on the
+   section type if known.  Otherwise d_type is set to ELF_T_BYTE.  If
+   the section contains compressed data then d_type is always set to
+   ELF_T_CHDR.  */
 extern Elf_Data *elf_getdata (Elf_Scn *__scn, Elf_Data *__data);
 
 /* Get uninterpreted section content.  */
diff --git a/libelf/libelf.map b/libelf/libelf.map
index de6d912a..10dc5059 100644
--- a/libelf/libelf.map
+++ b/libelf/libelf.map
@@ -138,3 +138,13 @@ ELFUTILS_1.6 {
   global:
     elf_getphdrnum;
 } ELFUTILS_1.5;
+
+ELFUTILS_1.7 {
+  global:
+    elf32_getchdr;
+    elf64_getchdr;
+    gelf_getchdr;
+
+    elf_compress;
+    elf_compress_gnu;
+} ELFUTILS_1.6;
diff --git a/libelf/libelfP.h b/libelf/libelfP.h
index 993c6556..57ccbce4 100644
--- a/libelf/libelfP.h
+++ b/libelf/libelfP.h
@@ -1,5 +1,5 @@
 /* Internal interfaces for libelf.
-   Copyright (C) 1998-2010 Red Hat, Inc.
+   Copyright (C) 1998-2010, 2015 Red Hat, Inc.
    This file is part of elfutils.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 1998.
 
@@ -38,6 +38,7 @@
 #include <gelf.h>
 
 #include <errno.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <string.h>
@@ -138,6 +139,13 @@ enum
   ELF_E_INVALID_PHDR,
   ELF_E_NO_PHDR,
   ELF_E_INVALID_OFFSET,
+  ELF_E_INVALID_SECTION_TYPE,
+  ELF_E_INVALID_SECTION_FLAGS,
+  ELF_E_NOT_COMPRESSED,
+  ELF_E_ALREADY_COMPRESSED,
+  ELF_E_UNKNOWN_COMPRESSION_TYPE,
+  ELF_E_COMPRESS_ERROR,
+  ELF_E_DECOMPRESS_ERROR,
   /* Keep this as the last entry.  */
   ELF_E_NUM
 };
@@ -230,6 +238,10 @@ struct Elf_Scn
   char *rawdata_base;		/* The unmodified data of the section.  */
   char *data_base;		/* The converted data of the section.  */
 
+  char *zdata_base;		/* The uncompressed data of the section.  */
+  size_t zdata_size;		/* If zdata_base != NULL, the size of data.  */
+  size_t zdata_align;		/* If zdata_base != NULL, the addralign.  */
+
   struct Elf_ScnList *list;	/* Pointer to the section list element the
 				   data is in.  */
 };
@@ -438,6 +450,11 @@ extern const uint_fast8_t __libelf_type_aligns[EV_NUM - 1][ELFCLASSNUM - 1][ELF_
 # define __libelf_type_align(class, type)	1
 #endif
 
+/* Given an Elf handle and a section type returns the Elf_Data d_type.
+   Should not be called when SHF_COMPRESSED is set, the d_type should
+   be ELF_T_BYTE.  */
+extern Elf_Type __libelf_data_type (Elf *elf, int sh_type) internal_function;
+
 /* The libelf API does not have such a function but it is still useful.
    Get the memory size for the given type.
 
@@ -578,6 +595,22 @@ extern GElf_Sym *__gelf_getsym_internal (Elf_Data *__data, int __ndx,
 extern uint32_t __libelf_crc32 (uint32_t crc, unsigned char *buf, size_t len)
      attribute_hidden;
 
+extern void * __libelf_compress (Elf_Scn *scn, size_t hsize, int ei_data,
+				 size_t *orig_size, size_t *orig_addralign,
+				 size_t *size, bool force)
+     internal_function;
+
+extern void * __libelf_decompress (void *buf_in, size_t size_in,
+				   size_t size_out) internal_function;
+extern void * __libelf_decompress_elf (Elf_Scn *scn,
+				       size_t *size_out, size_t *addralign)
+     internal_function;
+
+
+extern void __libelf_reset_rawdata (Elf_Scn *scn, void *buf, size_t size,
+				    size_t align, Elf_Type type)
+     internal_function;
+
 
 /* We often have to update a flag iff a value changed.  Make this
    convenient.  */