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/*
* cbfs-mkstage
*
* Copyright (C) 2008 Jordan Crouse <jordan@cosmicpenguin.net>
* 2009 coresystems GmbH
* written by Patrick Georgi <patrick.georgi@coresystems.de>
* Copyright (C) 2012 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"
#include "common.h"
#include "cbfs.h"
/* returns size of result, or -1 if error.
* Note that, with the new code, this function
* works for all elf files, not just the restricted set.
*/
int parse_elf_to_stage(const struct buffer *input, struct buffer *output,
uint32_t arch, comp_algo algo, uint32_t *location)
{
Elf64_Phdr *phdr;
Elf64_Ehdr ehdr;
char *buffer;
struct buffer outheader;
int headers;
int i, outlen;
uint32_t data_start, data_end, mem_end;
comp_func_ptr compress = compression_function(algo);
if (!compress)
return -1;
DEBUG("start: parse_elf_to_stage(location=0x%x)\n", *location);
if (elf_headers(input, arch, &ehdr, &phdr, NULL) < 0)
return -1;
headers = ehdr.e_phnum;
data_start = ~0;
data_end = 0;
mem_end = 0;
for (i = 0; i < headers; i++) {
unsigned int start, mend, rend;
if (phdr[i].p_type != PT_LOAD)
continue;
/* Empty segments are never interesting */
if (phdr[i].p_memsz == 0)
continue;
/* BSS */
start = phdr[i].p_paddr;
mend = start + phdr[i].p_memsz;
rend = start + phdr[i].p_filesz;
if (start < data_start)
data_start = start;
if (rend > data_end)
data_end = rend;
if (mend > mem_end)
mem_end = mend;
}
if (data_start < *location) {
data_start = *location;
}
if (data_end <= data_start) {
ERROR("data ends (%08lx) before it starts (%08lx). Make sure "
"the ELF file is correct and resides in ROM space.\n",
(unsigned long)data_end, (unsigned long)data_start);
exit(1);
}
/* allocate an intermediate buffer for the data */
buffer = calloc(data_end - data_start, 1);
if (buffer == NULL) {
ERROR("Unable to allocate memory: %m\n");
return -1;
}
/* Copy the file data into the buffer */
for (i = 0; i < headers; i++) {
unsigned int l_start, l_offset = 0;
if (phdr[i].p_type != PT_LOAD)
continue;
if (phdr[i].p_memsz == 0)
continue;
l_start = phdr[i].p_paddr;
if (l_start < *location) {
l_offset = *location - l_start;
l_start = *location;
}
/* A legal ELF file can have a program header with
* non-zero length but zero-length file size and a
* non-zero offset which, added together, are > than
* input->size (i.e. the total file size). So we need
* to not even test in the case that p_filesz is zero.
*/
if (! phdr[i].p_filesz)
continue;
if (input->size < (phdr[i].p_offset + phdr[i].p_filesz)){
ERROR("Underflow copying out the segment."
"File has %zu bytes left, segment end is %zu\n",
input->size, (size_t)(phdr[i].p_offset + phdr[i].p_filesz));
free(buffer);
return -1;
}
memcpy(buffer + (l_start - data_start),
&input->data[phdr[i].p_offset + l_offset],
phdr[i].p_filesz - l_offset);
}
/* Now make the output buffer */
if (buffer_create(output, sizeof(struct cbfs_stage) + data_end - data_start,
input->name) != 0) {
ERROR("Unable to allocate memory: %m\n");
free(buffer);
return -1;
}
memset(output->data, 0, output->size);
/* Compress the data, at which point we'll know information
* to fill out the header. This seems backward but it works because
* - the output header is a known size (not always true in many xdr's)
* - we do need to know the compressed output size first
*/
compress(buffer, data_end - data_start,
(output->data + sizeof(struct cbfs_stage)),
&outlen);
free(buffer);
/* Set up for output marshaling. */
outheader.data = output->data;
outheader.size = 0;
/* N.B. The original plan was that SELF data was B.E.
* but: this is all L.E.
* Maybe we should just change the spec.
*/
xdr_le.put32(&outheader, algo);
xdr_le.put64(&outheader, ehdr.e_entry);
xdr_le.put64(&outheader, data_start);
xdr_le.put32(&outheader, outlen);
xdr_le.put32(&outheader, mem_end - data_start);
if (*location)
*location -= sizeof(struct cbfs_stage);
output->size = sizeof(struct cbfs_stage) + outlen;
return 0;
}
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