Squashed 'third_party/elfutils/' content from commit 555e15e
Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/libelf/elf32_checksum.c b/libelf/elf32_checksum.c
new file mode 100644
index 0000000..f9dfccb
--- /dev/null
+++ b/libelf/elf32_checksum.c
@@ -0,0 +1,168 @@
+/* Compute simple checksum from permanent parts of the ELF file.
+ Copyright (C) 2002, 2003, 2004, 2005, 2009, 2015 Red Hat, Inc.
+ This file is part of elfutils.
+ Written by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+ 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 <assert.h>
+#include <endian.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <string.h>
+
+#include "gelf.h"
+#include "libelfP.h"
+#include "elf-knowledge.h"
+
+#ifndef LIBELFBITS
+# define LIBELFBITS 32
+#endif
+
+
+#define process_block(crc, data) \
+ __libelf_crc32 (crc, data->d_buf, data->d_size)
+
+
+long int
+elfw2(LIBELFBITS,checksum) (Elf *elf)
+{
+ size_t shstrndx;
+ Elf_Scn *scn;
+ long int result = 0;
+ unsigned char *ident;
+ bool same_byte_order;
+
+ if (elf == NULL)
+ return -1l;
+
+ /* Find the section header string table. */
+ if (INTUSE(elf_getshdrstrndx) (elf, &shstrndx) < 0)
+ {
+ /* This can only happen if the ELF handle is not for real. */
+ __libelf_seterrno (ELF_E_INVALID_HANDLE);
+ return -1l;
+ }
+
+ /* Determine whether the byte order of the file and that of the host
+ is the same. */
+ ident = elf->state.ELFW(elf,LIBELFBITS).ehdr->e_ident;
+ same_byte_order = ((ident[EI_DATA] == ELFDATA2LSB
+ && __BYTE_ORDER == __LITTLE_ENDIAN)
+ || (ident[EI_DATA] == ELFDATA2MSB
+ && __BYTE_ORDER == __BIG_ENDIAN));
+
+ /* If we don't have native byte order, we will likely need to
+ convert the data with xlate functions. We do it upfront instead
+ of relocking mid-iteration. */
+ if (!likely (same_byte_order))
+ rwlock_wrlock (elf->lock);
+ else
+ rwlock_rdlock (elf->lock);
+
+ /* Iterate over all sections to find those which are not strippable. */
+ scn = NULL;
+ while ((scn = INTUSE(elf_nextscn) (elf, scn)) != NULL)
+ {
+ GElf_Shdr shdr_mem;
+ GElf_Shdr *shdr;
+ Elf_Data *data;
+
+ /* Get the section header. */
+ shdr = INTUSE(gelf_getshdr) (scn, &shdr_mem);
+ if (shdr == NULL)
+ {
+ __libelf_seterrno (ELF_E_INVALID_SECTION_HEADER);
+ result = -1l;
+ goto out;
+ }
+
+ if (SECTION_STRIP_P (shdr,
+ INTUSE(elf_strptr) (elf, shstrndx, shdr->sh_name),
+ true))
+ /* The section can be stripped. Don't use it. */
+ continue;
+
+ /* Do not look at NOBITS sections. */
+ if (shdr->sh_type == SHT_NOBITS)
+ continue;
+
+ /* To compute the checksum we need to get to the data. For
+ repeatable results we must use the external format. The data
+ we get with 'elf'getdata' might be changed for endianess
+ reasons. Therefore we use 'elf_rawdata' if possible. But
+ this function can fail if the data was constructed by the
+ program. In this case we have to use 'elf_getdata' and
+ eventually convert the data to the external format. */
+ data = INTUSE(elf_rawdata) (scn, NULL);
+ if (data != NULL)
+ {
+ /* The raw data is available. */
+ result = process_block (result, data);
+
+ /* Maybe the user added more data. These blocks cannot be
+ read using 'elf_rawdata'. Simply proceed with looking
+ for more data block with 'elf_getdata'. */
+ }
+
+ /* Iterate through the list of data blocks. */
+ while ((data = INTUSE(elf_getdata) (scn, data)) != NULL)
+ /* If the file byte order is the same as the host byte order
+ process the buffer directly. If the data is just a stream
+ of bytes which the library will not convert we can use it
+ as well. */
+ if (likely (same_byte_order) || data->d_type == ELF_T_BYTE)
+ result = process_block (result, data);
+ else
+ {
+ /* Convert the data to file byte order. */
+ if (INTUSE(elfw2(LIBELFBITS,xlatetof)) (data, data, ident[EI_DATA])
+ == NULL)
+ {
+ result = -1l;
+ goto out;
+ }
+
+ result = process_block (result, data);
+
+ /* And convert it back. */
+ if (INTUSE(elfw2(LIBELFBITS,xlatetom)) (data, data, ident[EI_DATA])
+ == NULL)
+ {
+ result = -1l;
+ goto out;
+ }
+ }
+ }
+
+ out:
+ rwlock_unlock (elf->lock);
+ return result;
+}
+INTDEF(elfw2(LIBELFBITS,checksum))