2013-12-30 22:16:18 +01:00
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/*
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* elf header parsing.
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*
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* Copyright (C) 2013 Google, Inc.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; version 2 of the License.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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2014-03-05 19:12:09 +01:00
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#include "elfparsing.h"
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2013-12-30 22:16:18 +01:00
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#include "common.h"
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#include "cbfs.h"
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/*
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* Short form: this is complicated, but we've tried making it simple
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* and we keep hitting problems with our ELF parsing.
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*
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* The ELF parsing situation has always been a bit tricky. In fact,
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* we (and most others) have been getting it wrong in small ways for
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* years. Recently this has caused real trouble for the ARM V8 build.
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* In this file we attempt to finally get it right for all variations
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* of endian-ness and word size and target architectures and
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* architectures we might get run on. Phew!. To do this we borrow a
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* page from the FreeBSD NFS xdr model (see elf_ehdr and elf_phdr),
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* the Plan 9 endianness functions (see xdr.c), and Go interfaces (see
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* how we use buffer structs in this file). This ends up being a bit
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* wordy at the lowest level, but greatly simplifies the elf parsing
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* code and removes a common source of bugs, namely, forgetting to
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* flip type endianness when referencing a struct member.
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*
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* ELF files can have four combinations of data layout: 32/64, and
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* big/little endian. Further, to add to the fun, depending on the
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* word size, the size of the ELF structs varies. The coreboot SELF
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* format is simpler in theory: it's supposed to be always BE, and the
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* various struct members allow room for growth: the entry point is
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* always 64 bits, for example, so the size of a SELF struct is
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* constant, regardless of target architecture word size. Hence, we
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* need to do some transformation of the ELF files.
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*
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* A given architecture, realistically, only supports one of the four
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* combinations at a time as the 'native' format. Hence, our code has
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* been sprinkled with every variation of [nh]to[hn][sll] over the
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* years. We've never quite gotten it all right, however, and a quick
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* pass over this code revealed another bug. It's all worked because,
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* until now, all the working platforms that had CBFS were 32 LE. Even then,
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* however, bugs crept in: we recently realized that we're not
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* transforming the entry point to big format when we store into the
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* SELF image.
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*
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* The problem is essentially an XDR operation:
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* we have something in a foreign format and need to transform it.
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* It's most like XDR because:
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* 1) the byte order can be wrong
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* 2) the word size can be wrong
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* 3) the size of elements in the stream depends on the value
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* of other elements in the stream
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* it's not like XDR because:
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* 1) the byte order can be right
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* 2) the word size can be right
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* 3) the struct members are all on a natural alignment
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*
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* Hence, this new approach. To cover word size issues, we *always*
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* transform the two structs we care about, the file header and
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* program header, into a native struct in the 64 bit format:
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*
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* [32,little] -> [Elf64_Ehdr, Elf64_Phdr]
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* [64,little] -> [Elf64_Ehdr, Elf64_Phdr]
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* [32,big] -> [Elf64_Ehdr, Elf64_Phdr]
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* [64,big] -> [Elf64_Ehdr, Elf64_Phdr]
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* Then we just use those structs, and all the need for inline ntoh* goes away,
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* as well as all the chances for error.
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* This works because all the SELF structs have fields large enough for
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* the largest ELF 64 struct members, and all the Elf64 struct members
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* are at least large enough for all ELF 32 struct members.
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* We end up with one function to do all our ELF parsing, and two functions
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* to transform the headers. For the put case, we also have
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* XDR functions, and hopefully we'll never again spend 5 years with the
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* wrong endian-ness on an output value :-)
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* This should work for all word sizes and endianness we hope to target.
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* I *really* don't want to be here for 128 bit addresses.
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*
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* The parse functions are called with a pointer to an input buffer
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* struct. One might ask: are there enough bytes in the input buffer?
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* We know there need to be at *least* sizeof(Elf32_Ehdr) +
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* sizeof(Elf32_Phdr) bytes. Realistically, there has to be some data
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* too. If we start to worry, though we have not in the past, we
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* might apply the simple test: the input buffer needs to be at least
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* sizeof(Elf64_Ehdr) + sizeof(Elf64_Phdr) bytes because, even if it's
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* ELF 32, there's got to be *some* data! This is not theoretically
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* accurate but it is actually good enough in practice. It allows the
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* header transformation code to ignore the possibility of underrun.
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*
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* We also must accomodate different ELF files, and hence formats,
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* in the same cbfs invocation. We might load a 64-bit payload
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* on a 32-bit machine; we might even have a mixed armv7/armv8
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* SOC or even a system with an x86/ARM!
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*
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* A possibly problematic (though unlikely to be so) assumption
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* is that we expect the BIOS to remain in the lowest 32 bits
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* of the physical address space. Since ARMV8 has standardized
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* on that, and x86_64 also has, this seems a safe assumption.
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*
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* To repeat, ELF structs are different sizes because ELF struct
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* members are different sizes, depending on values in the ELF file
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* header. For this we use the functions defined in xdr.c, which
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* consume bytes, convert the endianness, and advance the data pointer
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* in the buffer struct.
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*/
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2014-03-05 19:01:36 +01:00
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static int iself(const void *input)
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{
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const Elf32_Ehdr *ehdr = input;
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return !memcmp(ehdr->e_ident, ELFMAG, 4);
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}
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2013-12-30 22:16:18 +01:00
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/* Get the ident array, so we can figure out
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* endian-ness, word size, and in future other useful
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* parameters
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*/
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static void
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elf_eident(struct buffer *input, Elf64_Ehdr *ehdr)
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{
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2014-03-05 05:08:05 +01:00
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bgets(input, ehdr->e_ident, sizeof(ehdr->e_ident));
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2013-12-30 22:16:18 +01:00
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}
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2014-03-05 05:08:05 +01:00
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static int
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check_size(const struct buffer *b, size_t offset, size_t size, const char *desc)
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{
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if (size == 0)
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return 0;
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if (offset >= buffer_size(b) || (offset + size) > buffer_size(b)) {
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ERROR("The file is not large enough for the '%s'. "
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2014-03-16 00:15:57 +01:00
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"%zu bytes @ offset %zu, input %zu bytes.\n",
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2014-03-05 05:08:05 +01:00
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desc, size, offset, buffer_size(b));
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return -1;
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}
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return 0;
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}
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2013-12-30 22:16:18 +01:00
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static void
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elf_ehdr(struct buffer *input, Elf64_Ehdr *ehdr, struct xdr *xdr, int bit64)
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{
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ehdr->e_type = xdr->get16(input);
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ehdr->e_machine = xdr->get16(input);
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ehdr->e_version = xdr->get32(input);
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if (bit64){
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ehdr->e_entry = xdr->get64(input);
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ehdr->e_phoff = xdr->get64(input);
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ehdr->e_shoff = xdr->get64(input);
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} else {
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ehdr->e_entry = xdr->get32(input);
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ehdr->e_phoff = xdr->get32(input);
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ehdr->e_shoff = xdr->get32(input);
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}
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ehdr->e_flags = xdr->get32(input);
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ehdr->e_ehsize = xdr->get16(input);
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ehdr->e_phentsize = xdr->get16(input);
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ehdr->e_phnum = xdr->get16(input);
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ehdr->e_shentsize = xdr->get16(input);
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ehdr->e_shnum = xdr->get16(input);
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ehdr->e_shstrndx = xdr->get16(input);
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}
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static void
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elf_phdr(struct buffer *pinput, Elf64_Phdr *phdr,
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int entsize, struct xdr *xdr, int bit64)
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{
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/*
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* The entsize need not be sizeof(*phdr).
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* Hence, it is easier to keep a copy of the input,
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* as the xdr functions may not advance the input
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* pointer the full entsize; rather than get tricky
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* we just advance it below.
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*/
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2014-03-05 05:08:05 +01:00
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struct buffer input;
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buffer_clone(&input, pinput);
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2013-12-30 22:16:18 +01:00
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if (bit64){
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phdr->p_type = xdr->get32(&input);
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phdr->p_flags = xdr->get32(&input);
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phdr->p_offset = xdr->get64(&input);
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phdr->p_vaddr = xdr->get64(&input);
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phdr->p_paddr = xdr->get64(&input);
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phdr->p_filesz = xdr->get64(&input);
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phdr->p_memsz = xdr->get64(&input);
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phdr->p_align = xdr->get64(&input);
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} else {
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phdr->p_type = xdr->get32(&input);
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phdr->p_offset = xdr->get32(&input);
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phdr->p_vaddr = xdr->get32(&input);
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phdr->p_paddr = xdr->get32(&input);
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phdr->p_filesz = xdr->get32(&input);
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phdr->p_memsz = xdr->get32(&input);
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phdr->p_flags = xdr->get32(&input);
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phdr->p_align = xdr->get32(&input);
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}
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2014-03-05 05:08:05 +01:00
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buffer_seek(pinput, entsize);
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2013-12-30 22:16:18 +01:00
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}
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static void
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elf_shdr(struct buffer *pinput, Elf64_Shdr *shdr,
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int entsize, struct xdr *xdr, int bit64)
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{
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/*
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* The entsize need not be sizeof(*shdr).
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* Hence, it is easier to keep a copy of the input,
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* as the xdr functions may not advance the input
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* pointer the full entsize; rather than get tricky
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* we just advance it below.
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*/
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struct buffer input = *pinput;
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if (bit64){
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shdr->sh_name = xdr->get32(&input);
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shdr->sh_type = xdr->get32(&input);
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shdr->sh_flags = xdr->get64(&input);
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shdr->sh_addr = xdr->get64(&input);
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shdr->sh_offset = xdr->get64(&input);
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shdr->sh_size= xdr->get64(&input);
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shdr->sh_link = xdr->get32(&input);
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shdr->sh_info = xdr->get32(&input);
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shdr->sh_addralign = xdr->get64(&input);
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shdr->sh_entsize = xdr->get64(&input);
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} else {
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shdr->sh_name = xdr->get32(&input);
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shdr->sh_type = xdr->get32(&input);
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shdr->sh_flags = xdr->get32(&input);
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shdr->sh_addr = xdr->get32(&input);
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shdr->sh_offset = xdr->get32(&input);
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shdr->sh_size = xdr->get32(&input);
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shdr->sh_link = xdr->get32(&input);
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shdr->sh_info = xdr->get32(&input);
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shdr->sh_addralign = xdr->get32(&input);
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shdr->sh_entsize = xdr->get32(&input);
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}
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2014-03-05 05:08:05 +01:00
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buffer_seek(pinput, entsize);
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}
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2014-03-05 20:09:55 +01:00
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static int
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phdr_read(const struct buffer *in, struct parsed_elf *pelf,
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struct xdr *xdr, int bit64)
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2014-03-05 05:08:05 +01:00
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{
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struct buffer b;
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Elf64_Phdr *phdr;
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2014-03-05 20:09:55 +01:00
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Elf64_Ehdr *ehdr;
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2014-03-05 05:08:05 +01:00
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int i;
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2014-03-05 20:09:55 +01:00
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ehdr = &pelf->ehdr;
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2014-03-05 05:08:05 +01:00
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/* cons up an input buffer for the headers.
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* Note that the program headers can be anywhere,
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* per the ELF spec, You'd be surprised how many ELF
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* readers miss this little detail.
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*/
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buffer_splice(&b, in, ehdr->e_phoff, ehdr->e_phentsize * ehdr->e_phnum);
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if (check_size(in, ehdr->e_phoff, buffer_size(&b), "program headers"))
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2014-03-05 20:09:55 +01:00
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return -1;
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2014-03-05 05:08:05 +01:00
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/* gather up all the phdrs.
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* We do them all at once because there is more
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* than one loop over all the phdrs.
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*/
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2014-03-05 21:54:13 +01:00
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phdr = calloc(ehdr->e_phnum, sizeof(*phdr));
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2014-03-07 22:23:05 +01:00
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for (i = 0; i < ehdr->e_phnum; i++) {
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DEBUG("Parsing segment %d\n", i);
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2014-03-05 05:08:05 +01:00
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elf_phdr(&b, &phdr[i], ehdr->e_phentsize, xdr, bit64);
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2014-03-07 22:23:05 +01:00
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/* Ensure the contents are valid within the elf file. */
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if (check_size(in, phdr[i].p_offset, phdr[i].p_filesz,
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2014-08-09 16:58:00 +02:00
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"segment contents")) {
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free(phdr);
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2014-03-05 20:09:55 +01:00
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return -1;
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2014-08-09 16:58:00 +02:00
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}
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2014-03-07 22:23:05 +01:00
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}
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2014-03-05 20:09:55 +01:00
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pelf->phdr = phdr;
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return 0;
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2014-03-05 05:08:05 +01:00
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}
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2014-03-05 20:09:55 +01:00
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static int
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shdr_read(const struct buffer *in, struct parsed_elf *pelf,
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struct xdr *xdr, int bit64)
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2014-03-05 05:08:05 +01:00
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{
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struct buffer b;
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Elf64_Shdr *shdr;
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2014-03-05 20:09:55 +01:00
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Elf64_Ehdr *ehdr;
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2014-03-05 05:08:05 +01:00
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int i;
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2014-03-05 20:09:55 +01:00
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ehdr = &pelf->ehdr;
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2014-03-05 05:08:05 +01:00
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/* cons up an input buffer for the section headers.
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* Note that the section headers can be anywhere,
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|
|
* per the ELF spec, You'd be surprised how many ELF
|
|
|
|
* readers miss this little detail.
|
|
|
|
*/
|
|
|
|
buffer_splice(&b, in, ehdr->e_shoff, ehdr->e_shentsize * ehdr->e_shnum);
|
|
|
|
if (check_size(in, ehdr->e_shoff, buffer_size(&b), "section headers"))
|
2014-03-05 20:09:55 +01:00
|
|
|
return -1;
|
2014-03-05 05:08:05 +01:00
|
|
|
|
|
|
|
/* gather up all the shdrs. */
|
2014-03-05 21:54:13 +01:00
|
|
|
shdr = calloc(ehdr->e_shnum, sizeof(*shdr));
|
2014-03-07 22:23:05 +01:00
|
|
|
for (i = 0; i < ehdr->e_shnum; i++) {
|
|
|
|
DEBUG("Parsing section %d\n", i);
|
2014-03-05 05:08:05 +01:00
|
|
|
elf_shdr(&b, &shdr[i], ehdr->e_shentsize, xdr, bit64);
|
2014-03-07 22:23:05 +01:00
|
|
|
}
|
|
|
|
|
2014-03-05 20:09:55 +01:00
|
|
|
pelf->shdr = shdr;
|
|
|
|
|
|
|
|
return 0;
|
2013-12-30 22:16:18 +01:00
|
|
|
}
|
|
|
|
|
2014-03-05 20:57:30 +01:00
|
|
|
static int
|
|
|
|
reloc_read(const struct buffer *in, struct parsed_elf *pelf,
|
|
|
|
struct xdr *xdr, int bit64)
|
|
|
|
{
|
|
|
|
struct buffer b;
|
|
|
|
Elf64_Word i;
|
|
|
|
Elf64_Ehdr *ehdr;
|
|
|
|
|
|
|
|
ehdr = &pelf->ehdr;
|
|
|
|
pelf->relocs = calloc(ehdr->e_shnum, sizeof(Elf64_Rela *));
|
|
|
|
|
|
|
|
/* Allocate array for each section that contains relocation entries. */
|
|
|
|
for (i = 0; i < ehdr->e_shnum; i++) {
|
|
|
|
Elf64_Shdr *shdr;
|
|
|
|
Elf64_Rela *rela;
|
|
|
|
Elf64_Xword j;
|
|
|
|
Elf64_Xword nrelocs;
|
|
|
|
int is_rela;
|
|
|
|
|
|
|
|
shdr = &pelf->shdr[i];
|
|
|
|
|
|
|
|
/* Only process REL and RELA sections. */
|
|
|
|
if (shdr->sh_type != SHT_REL && shdr->sh_type != SHT_RELA)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
DEBUG("Checking relocation section %u\n", i);
|
|
|
|
|
|
|
|
/* Ensure the section that relocations apply is a valid. */
|
|
|
|
if (shdr->sh_info >= ehdr->e_shnum ||
|
|
|
|
shdr->sh_info == SHN_UNDEF) {
|
|
|
|
ERROR("Relocations apply to an invalid section: %u\n",
|
|
|
|
shdr[i].sh_info);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
is_rela = shdr->sh_type == SHT_RELA;
|
|
|
|
|
|
|
|
/* Determine the number relocations in this section. */
|
|
|
|
nrelocs = shdr->sh_size / shdr->sh_entsize;
|
|
|
|
|
|
|
|
pelf->relocs[i] = calloc(nrelocs, sizeof(Elf64_Rela));
|
|
|
|
|
|
|
|
buffer_splice(&b, in, shdr->sh_offset, shdr->sh_size);
|
|
|
|
if (check_size(in, shdr->sh_offset, buffer_size(&b),
|
|
|
|
"relocation section")) {
|
|
|
|
ERROR("Relocation section %u failed.\n", i);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
rela = pelf->relocs[i];
|
|
|
|
for (j = 0; j < nrelocs; j++) {
|
|
|
|
if (bit64) {
|
|
|
|
rela->r_offset = xdr->get64(&b);
|
|
|
|
rela->r_info = xdr->get64(&b);
|
|
|
|
if (is_rela)
|
|
|
|
rela->r_addend = xdr->get64(&b);
|
|
|
|
} else {
|
|
|
|
uint32_t r_info;
|
|
|
|
|
|
|
|
rela->r_offset = xdr->get32(&b);
|
|
|
|
r_info = xdr->get32(&b);
|
|
|
|
rela->r_info = ELF64_R_INFO(ELF32_R_SYM(r_info),
|
|
|
|
ELF32_R_TYPE(r_info));
|
|
|
|
if (is_rela)
|
|
|
|
rela->r_addend = xdr->get32(&b);
|
|
|
|
}
|
|
|
|
rela++;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2014-03-05 21:33:42 +01:00
|
|
|
static int strtab_read(const struct buffer *in, struct parsed_elf *pelf)
|
|
|
|
{
|
|
|
|
Elf64_Ehdr *ehdr;
|
|
|
|
Elf64_Word i;
|
|
|
|
|
|
|
|
ehdr = &pelf->ehdr;
|
|
|
|
|
|
|
|
if (ehdr->e_shstrndx >= ehdr->e_shnum) {
|
|
|
|
ERROR("Section header string table index out of range: %d\n",
|
|
|
|
ehdr->e_shstrndx);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* For each section of type SHT_STRTAB create a symtab buffer. */
|
|
|
|
pelf->strtabs = calloc(ehdr->e_shnum, sizeof(struct buffer *));
|
|
|
|
|
|
|
|
for (i = 0; i < ehdr->e_shnum; i++) {
|
|
|
|
struct buffer *b;
|
|
|
|
Elf64_Shdr *shdr = &pelf->shdr[i];
|
|
|
|
|
|
|
|
if (shdr->sh_type != SHT_STRTAB)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
b = calloc(1, sizeof(*b));
|
|
|
|
buffer_splice(b, in, shdr->sh_offset, shdr->sh_size);
|
|
|
|
if (check_size(in, shdr->sh_offset, buffer_size(b), "strtab")) {
|
|
|
|
ERROR("STRTAB section not within bounds: %d\n", i);
|
2014-08-09 16:58:00 +02:00
|
|
|
free(b);
|
2014-03-05 21:33:42 +01:00
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
pelf->strtabs[i] = b;
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2014-03-05 23:41:27 +01:00
|
|
|
static int
|
|
|
|
symtab_read(const struct buffer *in, struct parsed_elf *pelf,
|
|
|
|
struct xdr *xdr, int bit64)
|
|
|
|
{
|
|
|
|
Elf64_Ehdr *ehdr;
|
|
|
|
Elf64_Shdr *shdr;
|
|
|
|
Elf64_Half i;
|
|
|
|
Elf64_Xword nsyms;
|
|
|
|
Elf64_Sym *sym;
|
|
|
|
struct buffer b;
|
|
|
|
|
|
|
|
ehdr = &pelf->ehdr;
|
|
|
|
|
|
|
|
shdr = NULL;
|
|
|
|
for (i = 0; i < ehdr->e_shnum; i++) {
|
|
|
|
if (pelf->shdr[i].sh_type != SHT_SYMTAB)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
if (shdr != NULL) {
|
|
|
|
ERROR("Multiple symbol sections found. %u and %u\n",
|
|
|
|
(unsigned int)(shdr - pelf->shdr), i);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
shdr = &pelf->shdr[i];
|
|
|
|
}
|
|
|
|
|
|
|
|
if (shdr == NULL) {
|
|
|
|
ERROR("No symbol table found.\n");
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
buffer_splice(&b, in, shdr->sh_offset, shdr->sh_size);
|
|
|
|
if (check_size(in, shdr->sh_offset, buffer_size(&b), "symtab"))
|
|
|
|
return -1;
|
|
|
|
|
|
|
|
nsyms = shdr->sh_size / shdr->sh_entsize;
|
|
|
|
|
|
|
|
pelf->syms = calloc(nsyms, sizeof(Elf64_Sym));
|
|
|
|
|
|
|
|
for (i = 0; i < nsyms; i++) {
|
|
|
|
sym = &pelf->syms[i];
|
|
|
|
|
|
|
|
if (bit64) {
|
|
|
|
sym->st_name = xdr->get32(&b);
|
|
|
|
sym->st_info = xdr->get8(&b);
|
|
|
|
sym->st_other = xdr->get8(&b);
|
|
|
|
sym->st_shndx = xdr->get16(&b);
|
|
|
|
sym->st_value = xdr->get64(&b);
|
|
|
|
sym->st_size = xdr->get64(&b);
|
|
|
|
} else {
|
|
|
|
sym->st_name = xdr->get32(&b);
|
|
|
|
sym->st_value = xdr->get32(&b);
|
|
|
|
sym->st_size = xdr->get32(&b);
|
|
|
|
sym->st_info = xdr->get8(&b);
|
|
|
|
sym->st_other = xdr->get8(&b);
|
|
|
|
sym->st_shndx = xdr->get16(&b);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2014-03-05 20:09:55 +01:00
|
|
|
int parse_elf(const struct buffer *pinput, struct parsed_elf *pelf, int flags)
|
2013-12-30 22:16:18 +01:00
|
|
|
{
|
|
|
|
struct xdr *xdr = &xdr_le;
|
|
|
|
int bit64 = 0;
|
2014-03-05 05:08:05 +01:00
|
|
|
struct buffer input;
|
2014-03-05 20:09:55 +01:00
|
|
|
Elf64_Ehdr *ehdr;
|
2014-03-05 05:08:05 +01:00
|
|
|
|
2014-03-05 20:09:55 +01:00
|
|
|
/* Zero out the parsed elf structure. */
|
|
|
|
memset(pelf, 0, sizeof(*pelf));
|
2013-12-30 22:16:18 +01:00
|
|
|
|
2014-03-05 05:08:05 +01:00
|
|
|
if (!iself(buffer_get(pinput))) {
|
2013-12-30 22:16:18 +01:00
|
|
|
ERROR("The stage file is not in ELF format!\n");
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
2014-03-05 20:09:55 +01:00
|
|
|
buffer_clone(&input, pinput);
|
|
|
|
ehdr = &pelf->ehdr;
|
2013-12-30 22:16:18 +01:00
|
|
|
elf_eident(&input, ehdr);
|
|
|
|
bit64 = ehdr->e_ident[EI_CLASS] == ELFCLASS64;
|
|
|
|
/* Assume LE unless we are sure otherwise.
|
|
|
|
* We're not going to take on the task of
|
|
|
|
* fully validating the ELF file. That way
|
|
|
|
* lies madness.
|
|
|
|
*/
|
|
|
|
if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB)
|
|
|
|
xdr = &xdr_be;
|
|
|
|
|
|
|
|
elf_ehdr(&input, ehdr, xdr, bit64);
|
|
|
|
|
2014-03-05 20:57:30 +01:00
|
|
|
/* Relocation processing requires section header parsing. */
|
|
|
|
if (flags & ELF_PARSE_RELOC)
|
|
|
|
flags |= ELF_PARSE_SHDR;
|
|
|
|
|
2014-03-05 21:33:42 +01:00
|
|
|
/* String table processing requires section header parsing. */
|
|
|
|
if (flags & ELF_PARSE_STRTAB)
|
|
|
|
flags |= ELF_PARSE_SHDR;
|
|
|
|
|
2014-03-05 23:41:27 +01:00
|
|
|
/* Symbole table processing requires section header parsing. */
|
|
|
|
if (flags & ELF_PARSE_SYMTAB)
|
|
|
|
flags |= ELF_PARSE_SHDR;
|
|
|
|
|
2014-03-05 20:09:55 +01:00
|
|
|
if ((flags & ELF_PARSE_PHDR) && phdr_read(pinput, pelf, xdr, bit64))
|
|
|
|
goto fail;
|
|
|
|
|
|
|
|
if ((flags & ELF_PARSE_SHDR) && shdr_read(pinput, pelf, xdr, bit64))
|
|
|
|
goto fail;
|
|
|
|
|
2014-03-05 20:57:30 +01:00
|
|
|
if ((flags & ELF_PARSE_RELOC) && reloc_read(pinput, pelf, xdr, bit64))
|
|
|
|
goto fail;
|
|
|
|
|
2014-03-05 21:33:42 +01:00
|
|
|
if ((flags & ELF_PARSE_STRTAB) && strtab_read(pinput, pelf))
|
|
|
|
goto fail;
|
|
|
|
|
2014-03-05 23:41:27 +01:00
|
|
|
if ((flags & ELF_PARSE_SYMTAB) && symtab_read(pinput, pelf, xdr, bit64))
|
|
|
|
goto fail;
|
|
|
|
|
2014-03-05 20:09:55 +01:00
|
|
|
return 0;
|
|
|
|
|
|
|
|
fail:
|
|
|
|
parsed_elf_destroy(pelf);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
void parsed_elf_destroy(struct parsed_elf *pelf)
|
|
|
|
{
|
2014-03-05 21:33:42 +01:00
|
|
|
Elf64_Half i;
|
|
|
|
|
2014-03-05 20:09:55 +01:00
|
|
|
free(pelf->phdr);
|
|
|
|
free(pelf->shdr);
|
2014-03-05 20:57:30 +01:00
|
|
|
if (pelf->relocs != NULL) {
|
|
|
|
for (i = 0; i < pelf->ehdr.e_shnum; i++)
|
|
|
|
free(pelf->relocs[i]);
|
|
|
|
}
|
|
|
|
free(pelf->relocs);
|
2014-03-05 21:33:42 +01:00
|
|
|
|
|
|
|
if (pelf->strtabs != NULL) {
|
|
|
|
for (i = 0; i < pelf->ehdr.e_shnum; i++)
|
|
|
|
free(pelf->strtabs[i]);
|
|
|
|
}
|
|
|
|
free(pelf->strtabs);
|
2014-03-05 23:41:27 +01:00
|
|
|
free(pelf->syms);
|
2014-03-05 20:09:55 +01:00
|
|
|
}
|
|
|
|
|
|
|
|
/* Get the headers from the buffer.
|
|
|
|
* Return -1 in the event of an error.
|
|
|
|
* The section headers are optional; if NULL
|
|
|
|
* is passed in for pshdr they won't be parsed.
|
|
|
|
* We don't (yet) make payload parsing optional
|
|
|
|
* because we've never seen a use case.
|
|
|
|
*/
|
|
|
|
int
|
|
|
|
elf_headers(const struct buffer *pinput,
|
|
|
|
uint32_t arch,
|
|
|
|
Elf64_Ehdr *ehdr,
|
|
|
|
Elf64_Phdr **pphdr,
|
|
|
|
Elf64_Shdr **pshdr)
|
|
|
|
{
|
|
|
|
|
|
|
|
struct parsed_elf pelf;
|
|
|
|
int flags;
|
|
|
|
|
|
|
|
flags = ELF_PARSE_PHDR;
|
|
|
|
|
|
|
|
if (pshdr != NULL)
|
|
|
|
flags |= ELF_PARSE_SHDR;
|
|
|
|
|
|
|
|
if (parse_elf(pinput, &pelf, flags))
|
|
|
|
return -1;
|
|
|
|
|
|
|
|
/* Copy out the parsed elf header. */
|
|
|
|
memcpy(ehdr, &pelf.ehdr, sizeof(*ehdr));
|
|
|
|
|
2013-12-30 22:16:18 +01:00
|
|
|
// The tool may work in architecture-independent way.
|
|
|
|
if (arch != CBFS_ARCHITECTURE_UNKNOWN &&
|
ARM: Generalize armv7 as arm.
There are ARM systems which are essentially heterogeneous multicores where
some cores implement a different ARM architecture version than other cores. A
specific example is the tegra124 which boots on an ARMv4 coprocessor while
most code, including most of the firmware, runs on the main ARMv7 core. To
support SOCs like this, the plan is to generalize the ARM architecture so that
all versions are available, and an SOC/CPU can then select what architecture
variant should be used for each component of the firmware; bootblock,
romstage, and ramstage.
Old-Change-Id: I22e048c3bc72bd56371e14200942e436c1e312c2
Signed-off-by: Gabe Black <gabeblack@google.com>
Reviewed-on: https://chromium-review.googlesource.com/171338
Reviewed-by: Gabe Black <gabeblack@chromium.org>
Commit-Queue: Gabe Black <gabeblack@chromium.org>
Tested-by: Gabe Black <gabeblack@chromium.org>
(cherry picked from commit 8423a41529da0ff67fb9873be1e2beb30b09ae2d)
Signed-off-by: Isaac Christensen <isaac.christensen@se-eng.com>
ARM: Split out ARMv7 code and make it possible to have other arch versions.
We don't always want to use ARMv7 code when building for ARM, so we should
separate out the ARMv7 code so it can be excluded, and also make it possible
to include code for some other version of the architecture instead, all per
build component for cases where we need more than one architecture version
at a time.
The tegra124 bootblock will ultimately need to be ARMv4, but until we have
some ARMv4 code to switch over to we can leave it set to ARMv7.
Old-Change-Id: Ia982c91057fac9c252397b7c866224f103761cc7
Reviewed-on: https://chromium-review.googlesource.com/171400
Reviewed-by: Gabe Black <gabeblack@chromium.org>
Tested-by: Gabe Black <gabeblack@chromium.org>
Commit-Queue: Gabe Black <gabeblack@chromium.org>
(cherry picked from commit 799514e6060aa97acdcf081b5c48f965be134483)
Squashed two related patches for splitting ARM support into general
ARM support and ARMv7 specific pieces.
Change-Id: Ic6511507953a2223c87c55f90252c4a4e1dd6010
Signed-off-by: Isaac Christensen <isaac.christensen@se-eng.com>
Reviewed-on: http://review.coreboot.org/6782
Tested-by: build bot (Jenkins)
2013-10-01 08:00:33 +02:00
|
|
|
!((ehdr->e_machine == EM_ARM) && (arch == CBFS_ARCHITECTURE_ARM)) &&
|
2013-12-30 22:16:18 +01:00
|
|
|
!((ehdr->e_machine == EM_386) && (arch == CBFS_ARCHITECTURE_X86))) {
|
|
|
|
ERROR("The stage file has the wrong architecture\n");
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
2014-03-05 20:09:55 +01:00
|
|
|
*pphdr = calloc(ehdr->e_phnum, sizeof(Elf64_Phdr));
|
|
|
|
memcpy(*pphdr, pelf.phdr, ehdr->e_phnum * sizeof(Elf64_Phdr));
|
2013-12-30 22:16:18 +01:00
|
|
|
|
2014-03-05 20:09:55 +01:00
|
|
|
if (pshdr != NULL) {
|
|
|
|
*pshdr = calloc(ehdr->e_shnum, sizeof(Elf64_Shdr));
|
|
|
|
memcpy(*pshdr, pelf.shdr, ehdr->e_shnum * sizeof(Elf64_Shdr));
|
|
|
|
}
|
2013-12-30 22:16:18 +01:00
|
|
|
|
2014-03-05 20:09:55 +01:00
|
|
|
parsed_elf_destroy(&pelf);
|
2013-12-30 22:16:18 +01:00
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
2014-03-11 17:48:56 +01:00
|
|
|
|
|
|
|
/* ELF Writing Support
|
|
|
|
*
|
|
|
|
* The ELF file is written according to the following layout:
|
|
|
|
* +------------------+
|
|
|
|
* | ELF Header |
|
|
|
|
* +------------------+
|
|
|
|
* | Section Headers |
|
|
|
|
* +------------------+
|
|
|
|
* | Program Headers |
|
|
|
|
* +------------------+
|
|
|
|
* | String table |
|
|
|
|
* +------------------+ <- 4KiB Aligned
|
|
|
|
* | Code/Data |
|
|
|
|
* +------------------+
|
|
|
|
*/
|
|
|
|
|
|
|
|
/* Arbitray maximum number of sections. */
|
|
|
|
#define MAX_SECTIONS 16
|
|
|
|
struct elf_writer_section {
|
|
|
|
Elf64_Shdr shdr;
|
|
|
|
struct buffer content;
|
|
|
|
const char *name;
|
|
|
|
};
|
|
|
|
|
|
|
|
struct elf_writer
|
|
|
|
{
|
|
|
|
Elf64_Ehdr ehdr;
|
|
|
|
struct xdr *xdr;
|
|
|
|
size_t num_secs;
|
|
|
|
struct elf_writer_section sections[MAX_SECTIONS];
|
|
|
|
Elf64_Phdr *phdrs;
|
|
|
|
struct elf_writer_section *shstrtab;
|
|
|
|
int bit64;
|
|
|
|
};
|
|
|
|
|
|
|
|
struct elf_writer *elf_writer_init(const Elf64_Ehdr *ehdr)
|
|
|
|
{
|
|
|
|
struct elf_writer *ew;
|
|
|
|
Elf64_Shdr shdr;
|
|
|
|
struct buffer empty_buffer;
|
|
|
|
|
|
|
|
if (!iself(ehdr))
|
|
|
|
return NULL;
|
|
|
|
|
|
|
|
ew = calloc(1, sizeof(*ew));
|
|
|
|
|
|
|
|
memcpy(&ew->ehdr, ehdr, sizeof(ew->ehdr));
|
|
|
|
|
|
|
|
ew->bit64 = ew->ehdr.e_ident[EI_CLASS] == ELFCLASS64;
|
|
|
|
|
|
|
|
/* Set the endinan ops. */
|
|
|
|
if (ew->ehdr.e_ident[EI_DATA] == ELFDATA2MSB)
|
|
|
|
ew->xdr = &xdr_be;
|
|
|
|
else
|
|
|
|
ew->xdr = &xdr_le;
|
|
|
|
|
|
|
|
/* Reset count and offsets */
|
|
|
|
ew->ehdr.e_phoff = 0;
|
|
|
|
ew->ehdr.e_shoff = 0;
|
|
|
|
ew->ehdr.e_shnum = 0;
|
|
|
|
ew->ehdr.e_phnum = 0;
|
|
|
|
|
|
|
|
memset(&empty_buffer, 0, sizeof(empty_buffer));
|
|
|
|
memset(&shdr, 0, sizeof(shdr));
|
|
|
|
|
|
|
|
/* Add SHT_NULL section header. */
|
|
|
|
shdr.sh_type = SHT_NULL;
|
|
|
|
elf_writer_add_section(ew, &shdr, &empty_buffer, NULL);
|
|
|
|
|
|
|
|
/* Add section header string table and maintain reference to it. */
|
|
|
|
shdr.sh_type = SHT_STRTAB;
|
|
|
|
elf_writer_add_section(ew, &shdr, &empty_buffer, ".shstrtab");
|
|
|
|
ew->ehdr.e_shstrndx = ew->num_secs - 1;
|
|
|
|
ew->shstrtab = &ew->sections[ew->ehdr.e_shstrndx];
|
|
|
|
|
|
|
|
return ew;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Clean up any internal state represented by ew. Aftewards the elf_writer
|
|
|
|
* is invalid.
|
|
|
|
*/
|
|
|
|
void elf_writer_destroy(struct elf_writer *ew)
|
|
|
|
{
|
|
|
|
if (ew->phdrs != NULL)
|
|
|
|
free(ew->phdrs);
|
|
|
|
free(ew);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Add a section to the ELF file. Section type, flags, and memsize are
|
|
|
|
* maintained from the passed in Elf64_Shdr. The buffer represents the
|
|
|
|
* content of the section while the name is the name of section itself.
|
|
|
|
* Returns < 0 on error, 0 on success.
|
|
|
|
*/
|
|
|
|
int elf_writer_add_section(struct elf_writer *ew, const Elf64_Shdr *shdr,
|
|
|
|
struct buffer *contents, const char *name)
|
|
|
|
{
|
|
|
|
struct elf_writer_section *newsh;
|
|
|
|
|
|
|
|
if (ew->num_secs == MAX_SECTIONS)
|
|
|
|
return -1;
|
|
|
|
|
|
|
|
newsh = &ew->sections[ew->num_secs];
|
|
|
|
ew->num_secs++;
|
|
|
|
|
|
|
|
memcpy(&newsh->shdr, shdr, sizeof(newsh->shdr));
|
|
|
|
newsh->shdr.sh_offset = 0;
|
|
|
|
|
|
|
|
newsh->name = name;
|
|
|
|
if (contents != NULL)
|
|
|
|
buffer_clone(&newsh->content, contents);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void ehdr_write(struct elf_writer *ew, struct buffer *m)
|
|
|
|
{
|
|
|
|
int i;
|
|
|
|
|
|
|
|
for (i = 0; i < EI_NIDENT; i++)
|
|
|
|
ew->xdr->put8(m, ew->ehdr.e_ident[i]);
|
|
|
|
ew->xdr->put16(m, ew->ehdr.e_type);
|
|
|
|
ew->xdr->put16(m, ew->ehdr.e_machine);
|
|
|
|
ew->xdr->put32(m, ew->ehdr.e_version);
|
|
|
|
if (ew->bit64) {
|
|
|
|
ew->xdr->put64(m, ew->ehdr.e_entry);
|
|
|
|
ew->xdr->put64(m, ew->ehdr.e_phoff);
|
|
|
|
ew->xdr->put64(m, ew->ehdr.e_shoff);
|
|
|
|
} else {
|
|
|
|
ew->xdr->put32(m, ew->ehdr.e_entry);
|
|
|
|
ew->xdr->put32(m, ew->ehdr.e_phoff);
|
|
|
|
ew->xdr->put32(m, ew->ehdr.e_shoff);
|
|
|
|
}
|
|
|
|
ew->xdr->put32(m, ew->ehdr.e_flags);
|
|
|
|
ew->xdr->put16(m, ew->ehdr.e_ehsize);
|
|
|
|
ew->xdr->put16(m, ew->ehdr.e_phentsize);
|
|
|
|
ew->xdr->put16(m, ew->ehdr.e_phnum);
|
|
|
|
ew->xdr->put16(m, ew->ehdr.e_shentsize);
|
|
|
|
ew->xdr->put16(m, ew->ehdr.e_shnum);
|
|
|
|
ew->xdr->put16(m, ew->ehdr.e_shstrndx);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void shdr_write(struct elf_writer *ew, size_t n, struct buffer *m)
|
|
|
|
{
|
|
|
|
struct xdr *xdr = ew->xdr;
|
|
|
|
int bit64 = ew->bit64;
|
|
|
|
struct elf_writer_section *sec = &ew->sections[n];
|
|
|
|
Elf64_Shdr *shdr = &sec->shdr;
|
|
|
|
|
|
|
|
xdr->put32(m, shdr->sh_name);
|
|
|
|
xdr->put32(m, shdr->sh_type);
|
|
|
|
if (bit64) {
|
2014-08-22 21:05:00 +02:00
|
|
|
xdr->put64(m, shdr->sh_flags);
|
2014-03-11 17:48:56 +01:00
|
|
|
xdr->put64(m, shdr->sh_addr);
|
|
|
|
xdr->put64(m, shdr->sh_offset);
|
|
|
|
xdr->put64(m, shdr->sh_size);
|
|
|
|
xdr->put32(m, shdr->sh_link);
|
|
|
|
xdr->put32(m, shdr->sh_info);
|
|
|
|
xdr->put64(m, shdr->sh_addralign);
|
|
|
|
xdr->put64(m, shdr->sh_entsize);
|
|
|
|
} else {
|
2014-08-22 21:05:00 +02:00
|
|
|
xdr->put32(m, shdr->sh_flags);
|
2014-03-11 17:48:56 +01:00
|
|
|
xdr->put32(m, shdr->sh_addr);
|
|
|
|
xdr->put32(m, shdr->sh_offset);
|
|
|
|
xdr->put32(m, shdr->sh_size);
|
|
|
|
xdr->put32(m, shdr->sh_link);
|
|
|
|
xdr->put32(m, shdr->sh_info);
|
|
|
|
xdr->put32(m, shdr->sh_addralign);
|
|
|
|
xdr->put32(m, shdr->sh_entsize);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static void
|
|
|
|
phdr_write(struct elf_writer *ew, struct buffer *m, Elf64_Phdr *phdr)
|
|
|
|
{
|
|
|
|
if (ew->bit64) {
|
|
|
|
ew->xdr->put32(m, phdr->p_type);
|
|
|
|
ew->xdr->put32(m, phdr->p_flags);
|
|
|
|
ew->xdr->put64(m, phdr->p_offset);
|
|
|
|
ew->xdr->put64(m, phdr->p_vaddr);
|
|
|
|
ew->xdr->put64(m, phdr->p_paddr);
|
|
|
|
ew->xdr->put64(m, phdr->p_filesz);
|
|
|
|
ew->xdr->put64(m, phdr->p_memsz);
|
|
|
|
ew->xdr->put64(m, phdr->p_align);
|
|
|
|
} else {
|
|
|
|
ew->xdr->put32(m, phdr->p_type);
|
|
|
|
ew->xdr->put32(m, phdr->p_offset);
|
|
|
|
ew->xdr->put32(m, phdr->p_vaddr);
|
|
|
|
ew->xdr->put32(m, phdr->p_paddr);
|
|
|
|
ew->xdr->put32(m, phdr->p_filesz);
|
|
|
|
ew->xdr->put32(m, phdr->p_memsz);
|
|
|
|
ew->xdr->put32(m, phdr->p_flags);
|
|
|
|
ew->xdr->put32(m, phdr->p_align);
|
|
|
|
}
|
|
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Serialize the ELF file to the output buffer. Return < 0 on error,
|
|
|
|
* 0 on success.
|
|
|
|
*/
|
|
|
|
int elf_writer_serialize(struct elf_writer *ew, struct buffer *out)
|
|
|
|
{
|
|
|
|
Elf64_Half i;
|
|
|
|
Elf64_Xword metadata_size;
|
|
|
|
Elf64_Xword program_size;
|
|
|
|
Elf64_Off shstroffset;
|
|
|
|
size_t shstrlen;
|
|
|
|
struct buffer metadata;
|
|
|
|
struct buffer phdrs;
|
|
|
|
struct buffer data;
|
|
|
|
struct buffer *strtab;
|
|
|
|
|
|
|
|
INFO("Writing %zu sections.\n", ew->num_secs);
|
|
|
|
|
|
|
|
/* Determine size of sections to be written. */
|
|
|
|
program_size = 0;
|
|
|
|
/* Start with 1 byte for first byte of section header string table. */
|
|
|
|
shstrlen = 1;
|
|
|
|
for (i = 0; i < ew->num_secs; i++) {
|
|
|
|
struct elf_writer_section *sec = &ew->sections[i];
|
|
|
|
|
|
|
|
if (sec->shdr.sh_flags & SHF_ALLOC)
|
|
|
|
ew->ehdr.e_phnum++;
|
|
|
|
|
|
|
|
program_size += buffer_size(&sec->content);
|
|
|
|
|
|
|
|
/* Keep track of the length sections' names. */
|
|
|
|
if (sec->name != NULL) {
|
|
|
|
sec->shdr.sh_name = shstrlen;
|
|
|
|
shstrlen += strlen(sec->name) + 1;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
ew->ehdr.e_shnum = ew->num_secs;
|
|
|
|
metadata_size = 0;
|
|
|
|
metadata_size += ew->ehdr.e_ehsize;
|
|
|
|
metadata_size += ew->ehdr.e_shnum * ew->ehdr.e_shentsize;
|
|
|
|
metadata_size += ew->ehdr.e_phnum * ew->ehdr.e_phentsize;
|
|
|
|
shstroffset = metadata_size;
|
|
|
|
/* Align up section header string size and metadata size to 4KiB */
|
|
|
|
metadata_size = ALIGN(metadata_size + shstrlen, 4096);
|
|
|
|
|
|
|
|
if (buffer_create(out, metadata_size + program_size, "elfout")) {
|
|
|
|
ERROR("Could not create output buffer for ELF.\n");
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
INFO("Created %zu output buffer for ELF file.\n", buffer_size(out));
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Write out ELF header. Section headers come right after ELF header
|
|
|
|
* followed by the program headers. Buffers need to be created first
|
|
|
|
* to do the writing.
|
|
|
|
*/
|
|
|
|
ew->ehdr.e_shoff = ew->ehdr.e_ehsize;
|
|
|
|
ew->ehdr.e_phoff = ew->ehdr.e_shoff +
|
|
|
|
ew->ehdr.e_shnum * ew->ehdr.e_shentsize;
|
|
|
|
|
|
|
|
buffer_splice(&metadata, out, 0, metadata_size);
|
|
|
|
buffer_splice(&phdrs, out, ew->ehdr.e_phoff,
|
|
|
|
ew->ehdr.e_phnum * ew->ehdr.e_phentsize);
|
|
|
|
buffer_splice(&data, out, metadata_size, program_size);
|
|
|
|
/* Set up the section header string table contents. */
|
|
|
|
strtab = &ew->shstrtab->content;
|
|
|
|
buffer_splice(strtab, out, shstroffset, shstrlen);
|
|
|
|
ew->shstrtab->shdr.sh_size = shstrlen;
|
|
|
|
|
|
|
|
/* Reset current locations. */
|
|
|
|
buffer_set_size(&metadata, 0);
|
|
|
|
buffer_set_size(&data, 0);
|
|
|
|
buffer_set_size(&phdrs, 0);
|
|
|
|
buffer_set_size(strtab, 0);
|
|
|
|
|
|
|
|
/* ELF Header */
|
|
|
|
ehdr_write(ew, &metadata);
|
|
|
|
|
|
|
|
/* Write out section headers, section strings, section content, and
|
|
|
|
* program headers. */
|
|
|
|
ew->xdr->put8(strtab, 0);
|
|
|
|
for (i = 0; i < ew->num_secs; i++) {
|
|
|
|
Elf64_Phdr phdr;
|
|
|
|
struct elf_writer_section *sec = &ew->sections[i];
|
|
|
|
|
|
|
|
/* Update section offsets. Be sure to not update SHT_NULL. */
|
|
|
|
if (sec == ew->shstrtab)
|
|
|
|
sec->shdr.sh_offset = shstroffset;
|
|
|
|
else if (i != 0)
|
|
|
|
sec->shdr.sh_offset = buffer_size(&data) +
|
|
|
|
metadata_size;
|
|
|
|
shdr_write(ew, i, &metadata);
|
|
|
|
|
|
|
|
/* Add section name to string table. */
|
|
|
|
if (sec->name != NULL)
|
|
|
|
bputs(strtab, sec->name, strlen(sec->name) + 1);
|
|
|
|
|
|
|
|
if (!(sec->shdr.sh_flags & SHF_ALLOC))
|
|
|
|
continue;
|
|
|
|
|
|
|
|
bputs(&data, buffer_get(&sec->content),
|
|
|
|
buffer_size(&sec->content));
|
|
|
|
|
|
|
|
phdr.p_type = PT_LOAD;
|
|
|
|
phdr.p_offset = sec->shdr.sh_offset;
|
|
|
|
phdr.p_vaddr = sec->shdr.sh_addr;
|
|
|
|
phdr.p_paddr = sec->shdr.sh_addr;
|
|
|
|
phdr.p_filesz = buffer_size(&sec->content);
|
|
|
|
phdr.p_memsz = sec->shdr.sh_size;
|
|
|
|
phdr.p_flags = 0;
|
|
|
|
if (sec->shdr.sh_flags & SHF_EXECINSTR)
|
|
|
|
phdr.p_flags |= PF_X | PF_R;
|
|
|
|
if (sec->shdr.sh_flags & SHF_WRITE)
|
|
|
|
phdr.p_flags |= PF_W;
|
|
|
|
phdr.p_align = sec->shdr.sh_addralign;
|
|
|
|
phdr_write(ew, &phdrs, &phdr);
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|