coreboot-kgpe-d16/util/cbfstool/elfheaders.c

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Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
2013-12-30 22:16:18 +01:00
/*
* elf header parsing.
*
* Copyright (C) 2013 Google, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program 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 a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "elfparsing.h"
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
2013-12-30 22:16:18 +01:00
#include "common.h"
#include "cbfs.h"
/*
* Short form: this is complicated, but we've tried making it simple
* and we keep hitting problems with our ELF parsing.
*
* The ELF parsing situation has always been a bit tricky. In fact,
* we (and most others) have been getting it wrong in small ways for
* years. Recently this has caused real trouble for the ARM V8 build.
* In this file we attempt to finally get it right for all variations
* of endian-ness and word size and target architectures and
* architectures we might get run on. Phew!. To do this we borrow a
* page from the FreeBSD NFS xdr model (see elf_ehdr and elf_phdr),
* the Plan 9 endianness functions (see xdr.c), and Go interfaces (see
* how we use buffer structs in this file). This ends up being a bit
* wordy at the lowest level, but greatly simplifies the elf parsing
* code and removes a common source of bugs, namely, forgetting to
* flip type endianness when referencing a struct member.
*
* ELF files can have four combinations of data layout: 32/64, and
* big/little endian. Further, to add to the fun, depending on the
* word size, the size of the ELF structs varies. The coreboot SELF
* format is simpler in theory: it's supposed to be always BE, and the
* various struct members allow room for growth: the entry point is
* always 64 bits, for example, so the size of a SELF struct is
* constant, regardless of target architecture word size. Hence, we
* need to do some transformation of the ELF files.
*
* A given architecture, realistically, only supports one of the four
* combinations at a time as the 'native' format. Hence, our code has
* been sprinkled with every variation of [nh]to[hn][sll] over the
* years. We've never quite gotten it all right, however, and a quick
* pass over this code revealed another bug. It's all worked because,
* until now, all the working platforms that had CBFS were 32 LE. Even then,
* however, bugs crept in: we recently realized that we're not
* transforming the entry point to big format when we store into the
* SELF image.
*
* The problem is essentially an XDR operation:
* we have something in a foreign format and need to transform it.
* It's most like XDR because:
* 1) the byte order can be wrong
* 2) the word size can be wrong
* 3) the size of elements in the stream depends on the value
* of other elements in the stream
* it's not like XDR because:
* 1) the byte order can be right
* 2) the word size can be right
* 3) the struct members are all on a natural alignment
*
* Hence, this new approach. To cover word size issues, we *always*
* transform the two structs we care about, the file header and
* program header, into a native struct in the 64 bit format:
*
* [32,little] -> [Elf64_Ehdr, Elf64_Phdr]
* [64,little] -> [Elf64_Ehdr, Elf64_Phdr]
* [32,big] -> [Elf64_Ehdr, Elf64_Phdr]
* [64,big] -> [Elf64_Ehdr, Elf64_Phdr]
* Then we just use those structs, and all the need for inline ntoh* goes away,
* as well as all the chances for error.
* This works because all the SELF structs have fields large enough for
* the largest ELF 64 struct members, and all the Elf64 struct members
* are at least large enough for all ELF 32 struct members.
* We end up with one function to do all our ELF parsing, and two functions
* to transform the headers. For the put case, we also have
* XDR functions, and hopefully we'll never again spend 5 years with the
* wrong endian-ness on an output value :-)
* This should work for all word sizes and endianness we hope to target.
* I *really* don't want to be here for 128 bit addresses.
*
* The parse functions are called with a pointer to an input buffer
* struct. One might ask: are there enough bytes in the input buffer?
* We know there need to be at *least* sizeof(Elf32_Ehdr) +
* sizeof(Elf32_Phdr) bytes. Realistically, there has to be some data
* too. If we start to worry, though we have not in the past, we
* might apply the simple test: the input buffer needs to be at least
* sizeof(Elf64_Ehdr) + sizeof(Elf64_Phdr) bytes because, even if it's
* ELF 32, there's got to be *some* data! This is not theoretically
* accurate but it is actually good enough in practice. It allows the
* header transformation code to ignore the possibility of underrun.
*
* We also must accomodate different ELF files, and hence formats,
* in the same cbfs invocation. We might load a 64-bit payload
* on a 32-bit machine; we might even have a mixed armv7/armv8
* SOC or even a system with an x86/ARM!
*
* A possibly problematic (though unlikely to be so) assumption
* is that we expect the BIOS to remain in the lowest 32 bits
* of the physical address space. Since ARMV8 has standardized
* on that, and x86_64 also has, this seems a safe assumption.
*
* To repeat, ELF structs are different sizes because ELF struct
* members are different sizes, depending on values in the ELF file
* header. For this we use the functions defined in xdr.c, which
* consume bytes, convert the endianness, and advance the data pointer
* in the buffer struct.
*/
static int iself(const void *input)
{
const Elf32_Ehdr *ehdr = input;
return !memcmp(ehdr->e_ident, ELFMAG, 4);
}
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
2013-12-30 22:16:18 +01:00
/* Get the ident array, so we can figure out
* endian-ness, word size, and in future other useful
* parameters
*/
static void
elf_eident(struct buffer *input, Elf64_Ehdr *ehdr)
{
bgets(input, ehdr->e_ident, sizeof(ehdr->e_ident));
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
2013-12-30 22:16:18 +01:00
}
static int
check_size(const struct buffer *b, size_t offset, size_t size, const char *desc)
{
if (size == 0)
return 0;
if (offset >= buffer_size(b) || (offset + size) > buffer_size(b)) {
ERROR("The file is not large enough for the '%s'. "
"%zu bytes @ offset %zu, input %zu bytes.\n",
desc, size, offset, buffer_size(b));
return -1;
}
return 0;
}
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
2013-12-30 22:16:18 +01:00
static void
elf_ehdr(struct buffer *input, Elf64_Ehdr *ehdr, struct xdr *xdr, int bit64)
{
ehdr->e_type = xdr->get16(input);
ehdr->e_machine = xdr->get16(input);
ehdr->e_version = xdr->get32(input);
if (bit64){
ehdr->e_entry = xdr->get64(input);
ehdr->e_phoff = xdr->get64(input);
ehdr->e_shoff = xdr->get64(input);
} else {
ehdr->e_entry = xdr->get32(input);
ehdr->e_phoff = xdr->get32(input);
ehdr->e_shoff = xdr->get32(input);
}
ehdr->e_flags = xdr->get32(input);
ehdr->e_ehsize = xdr->get16(input);
ehdr->e_phentsize = xdr->get16(input);
ehdr->e_phnum = xdr->get16(input);
ehdr->e_shentsize = xdr->get16(input);
ehdr->e_shnum = xdr->get16(input);
ehdr->e_shstrndx = xdr->get16(input);
}
static void
elf_phdr(struct buffer *pinput, Elf64_Phdr *phdr,
int entsize, struct xdr *xdr, int bit64)
{
/*
* The entsize need not be sizeof(*phdr).
* Hence, it is easier to keep a copy of the input,
* as the xdr functions may not advance the input
* pointer the full entsize; rather than get tricky
* we just advance it below.
*/
struct buffer input;
buffer_clone(&input, pinput);
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
2013-12-30 22:16:18 +01:00
if (bit64){
phdr->p_type = xdr->get32(&input);
phdr->p_flags = xdr->get32(&input);
phdr->p_offset = xdr->get64(&input);
phdr->p_vaddr = xdr->get64(&input);
phdr->p_paddr = xdr->get64(&input);
phdr->p_filesz = xdr->get64(&input);
phdr->p_memsz = xdr->get64(&input);
phdr->p_align = xdr->get64(&input);
} else {
phdr->p_type = xdr->get32(&input);
phdr->p_offset = xdr->get32(&input);
phdr->p_vaddr = xdr->get32(&input);
phdr->p_paddr = xdr->get32(&input);
phdr->p_filesz = xdr->get32(&input);
phdr->p_memsz = xdr->get32(&input);
phdr->p_flags = xdr->get32(&input);
phdr->p_align = xdr->get32(&input);
}
buffer_seek(pinput, entsize);
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
2013-12-30 22:16:18 +01:00
}
static void
elf_shdr(struct buffer *pinput, Elf64_Shdr *shdr,
int entsize, struct xdr *xdr, int bit64)
{
/*
* The entsize need not be sizeof(*shdr).
* Hence, it is easier to keep a copy of the input,
* as the xdr functions may not advance the input
* pointer the full entsize; rather than get tricky
* we just advance it below.
*/
struct buffer input = *pinput;
if (bit64){
shdr->sh_name = xdr->get32(&input);
shdr->sh_type = xdr->get32(&input);
shdr->sh_flags = xdr->get64(&input);
shdr->sh_addr = xdr->get64(&input);
shdr->sh_offset = xdr->get64(&input);
shdr->sh_size= xdr->get64(&input);
shdr->sh_link = xdr->get32(&input);
shdr->sh_info = xdr->get32(&input);
shdr->sh_addralign = xdr->get64(&input);
shdr->sh_entsize = xdr->get64(&input);
} else {
shdr->sh_name = xdr->get32(&input);
shdr->sh_type = xdr->get32(&input);
shdr->sh_flags = xdr->get32(&input);
shdr->sh_addr = xdr->get32(&input);
shdr->sh_offset = xdr->get32(&input);
shdr->sh_size = xdr->get32(&input);
shdr->sh_link = xdr->get32(&input);
shdr->sh_info = xdr->get32(&input);
shdr->sh_addralign = xdr->get32(&input);
shdr->sh_entsize = xdr->get32(&input);
}
buffer_seek(pinput, entsize);
}
static int
phdr_read(const struct buffer *in, struct parsed_elf *pelf,
struct xdr *xdr, int bit64)
{
struct buffer b;
Elf64_Phdr *phdr;
Elf64_Ehdr *ehdr;
int i;
ehdr = &pelf->ehdr;
/* cons up an input buffer for the headers.
* Note that the program headers can be anywhere,
* per the ELF spec, You'd be surprised how many ELF
* readers miss this little detail.
*/
buffer_splice(&b, in, ehdr->e_phoff, ehdr->e_phentsize * ehdr->e_phnum);
if (check_size(in, ehdr->e_phoff, buffer_size(&b), "program headers"))
return -1;
/* gather up all the phdrs.
* We do them all at once because there is more
* than one loop over all the phdrs.
*/
phdr = calloc(ehdr->e_phnum, sizeof(*phdr));
for (i = 0; i < ehdr->e_phnum; i++) {
DEBUG("Parsing segment %d\n", i);
elf_phdr(&b, &phdr[i], ehdr->e_phentsize, xdr, bit64);
/* Ensure the contents are valid within the elf file. */
if (check_size(in, phdr[i].p_offset, phdr[i].p_filesz,
"segment contents")) {
free(phdr);
return -1;
}
}
pelf->phdr = phdr;
return 0;
}
static int
shdr_read(const struct buffer *in, struct parsed_elf *pelf,
struct xdr *xdr, int bit64)
{
struct buffer b;
Elf64_Shdr *shdr;
Elf64_Ehdr *ehdr;
int i;
ehdr = &pelf->ehdr;
/* cons up an input buffer for the section headers.
* Note that the section headers can be anywhere,
* 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"))
return -1;
/* gather up all the shdrs. */
shdr = calloc(ehdr->e_shnum, sizeof(*shdr));
for (i = 0; i < ehdr->e_shnum; i++) {
DEBUG("Parsing section %d\n", i);
elf_shdr(&b, &shdr[i], ehdr->e_shentsize, xdr, bit64);
}
pelf->shdr = shdr;
return 0;
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
2013-12-30 22:16:18 +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;
}
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);
free(b);
return -1;
}
pelf->strtabs[i] = b;
}
return 0;
}
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;
}
int parse_elf(const struct buffer *pinput, struct parsed_elf *pelf, int flags)
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
2013-12-30 22:16:18 +01:00
{
struct xdr *xdr = &xdr_le;
int bit64 = 0;
struct buffer input;
Elf64_Ehdr *ehdr;
/* Zero out the parsed elf structure. */
memset(pelf, 0, sizeof(*pelf));
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
2013-12-30 22:16:18 +01:00
if (!iself(buffer_get(pinput))) {
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
2013-12-30 22:16:18 +01:00
ERROR("The stage file is not in ELF format!\n");
return -1;
}
buffer_clone(&input, pinput);
ehdr = &pelf->ehdr;
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
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);
/* Relocation processing requires section header parsing. */
if (flags & ELF_PARSE_RELOC)
flags |= ELF_PARSE_SHDR;
/* String table processing requires section header parsing. */
if (flags & ELF_PARSE_STRTAB)
flags |= ELF_PARSE_SHDR;
/* Symbole table processing requires section header parsing. */
if (flags & ELF_PARSE_SYMTAB)
flags |= ELF_PARSE_SHDR;
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;
if ((flags & ELF_PARSE_RELOC) && reloc_read(pinput, pelf, xdr, bit64))
goto fail;
if ((flags & ELF_PARSE_STRTAB) && strtab_read(pinput, pelf))
goto fail;
if ((flags & ELF_PARSE_SYMTAB) && symtab_read(pinput, pelf, xdr, bit64))
goto fail;
return 0;
fail:
parsed_elf_destroy(pelf);
return -1;
}
void parsed_elf_destroy(struct parsed_elf *pelf)
{
Elf64_Half i;
free(pelf->phdr);
free(pelf->shdr);
if (pelf->relocs != NULL) {
for (i = 0; i < pelf->ehdr.e_shnum; i++)
free(pelf->relocs[i]);
}
free(pelf->relocs);
if (pelf->strtabs != NULL) {
for (i = 0; i < pelf->ehdr.e_shnum; i++)
free(pelf->strtabs[i]);
}
free(pelf->strtabs);
free(pelf->syms);
}
/* 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));
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
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)) &&
!((ehdr->e_machine == EM_RISCV) && (arch == CBFS_ARCHITECTURE_RISCV)) &&
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
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;
}
*pphdr = calloc(ehdr->e_phnum, sizeof(Elf64_Phdr));
memcpy(*pphdr, pelf.phdr, ehdr->e_phnum * sizeof(Elf64_Phdr));
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
2013-12-30 22:16:18 +01:00
if (pshdr != NULL) {
*pshdr = calloc(ehdr->e_shnum, sizeof(Elf64_Shdr));
memcpy(*pshdr, pelf.shdr, ehdr->e_shnum * sizeof(Elf64_Shdr));
}
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
2013-12-30 22:16:18 +01:00
parsed_elf_destroy(&pelf);
Add section header parsing and use it in the mk-payload step This completes the improvements to the ELF file parsing code. We can now parse section headers too, across all 4 combinations of word size and endianness. I had hoped to completely remove the use of htonl until I found it in cbfs_image.c. That's a battle for another day. There's now a handy macro to create magic numbers in host byte order. I'm using it for all the PAYLOAD_SEGMENT_* constants and maybe we can use it for the others too, but this is sensitive code and I'd rather change one thing at a time. To maximize the ease of use for users, elf parsing is accomplished with just one function: int elf_headers(const struct buffer *pinput, Elf64_Ehdr *ehdr, Elf64_Phdr **pphdr, Elf64_Shdr **pshdr) which requires the ehdr and pphdr pointers to be non-NULL, but allows the pshdr to be NULL. If pshdr is NULL, the code will not try to read in section headers. To satisfy our powerful scripts, I had to remove the ^M from an unrelated microcode file. BUG=None TEST=Build a peppy image (known to boot) with old and new versions and verify they are bit-for-bit the same. This was also fully tested across all chromebooks for building and booting and running chromeos. BRANCH=None Change-Id: I54dad887d922428b6175fdb6a9cdfadd8a6bb889 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/181272 Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: http://review.coreboot.org/5098 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
2013-12-30 22:16:18 +01:00
return 0;
}
/* 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) {
xdr->put64(m, shdr->sh_flags);
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 {
xdr->put32(m, shdr->sh_flags);
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;
}