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/*
* cbfs-mkpayload
*
* Copyright (C) 2008 Jordan Crouse <jordan@cosmicpenguin.net>
* 2009 coresystems GmbH
* written by Patrick Georgi <patrick.georgi@coresystems.de>
*
* 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 <unistd.h>
#include "elf.h"
#include <fcntl.h>
#include <getopt.h>
#include <sys/stat.h>
#include "common.h"
#include "cbfs.h"
int parse_elf_to_payload(unsigned char *input, unsigned char **output,
comp_algo algo)
{
Elf32_Phdr *phdr;
Elf32_Ehdr *ehdr;
Elf32_Shdr *shdr;
char *header;
char *strtab;
unsigned char *sptr;
int headers;
int segments = 1;
int isize = 0, osize = 0;
int doffset = 0;
struct cbfs_payload_segment *segs;
int i;
if(!iself(input)){
printf("Fatal error: the payload file is not in ELF format!\n");
exit(1);
}
comp_func_ptr compress = compression_function(algo);
if (!compress)
return -1;
ehdr = (Elf32_Ehdr *) input;
headers = ehdr->e_phnum;
header = (char *)ehdr;
phdr = (Elf32_Phdr *) & (header[ehdr->e_phoff]);
shdr = (Elf32_Shdr *) & (header[ehdr->e_shoff]);
strtab = &header[shdr[ehdr->e_shstrndx].sh_offset];
/* Count the number of headers - look for the .notes.pinfo
* section */
for (i = 0; i < ehdr->e_shnum; i++) {
char *name;
if (i == ehdr->e_shstrndx)
continue;
if (shdr[i].sh_size == 0)
continue;
name = (char *)(strtab + shdr[i].sh_name);
if (!strcmp(name, ".note.pinfo")) {
segments++;
isize += (unsigned int)shdr[i].sh_size;
}
}
/* Now, regular headers - we only care about PT_LOAD headers,
* because thats what we're actually going to load
*/
for (i = 0; i < headers; i++) {
if (phdr[i].p_type != PT_LOAD)
continue;
/* Empty segments are never interesting */
if (phdr[i].p_memsz == 0)
continue;
isize += phdr[i].p_filesz;
segments++;
}
/* Allocate a block of memory to store the data in */
sptr =
calloc((segments * sizeof(struct cbfs_payload_segment)) + isize, 1);
doffset = (segments * sizeof(struct cbfs_payload_segment));
if (sptr == NULL)
goto err;
segs = (struct cbfs_payload_segment *)sptr;
segments = 0;
for (i = 0; i < ehdr->e_shnum; i++) {
char *name;
if (i == ehdr->e_shstrndx)
continue;
if (shdr[i].sh_size == 0)
continue;
name = (char *)(strtab + shdr[i].sh_name);
if (!strcmp(name, ".note.pinfo")) {
segs[segments].type = PAYLOAD_SEGMENT_PARAMS;
segs[segments].load_addr = 0;
segs[segments].len = (unsigned int)shdr[i].sh_size;
segs[segments].offset = doffset;
memcpy((unsigned long *)(sptr + doffset),
&header[shdr[i].sh_offset], shdr[i].sh_size);
doffset += segs[segments].len;
osize += segs[segments].len;
segments++;
}
}
for (i = 0; i < headers; i++) {
if (phdr[i].p_type != PT_LOAD)
continue;
if (phdr[i].p_memsz == 0)
continue;
if (phdr[i].p_filesz == 0) {
segs[segments].type = PAYLOAD_SEGMENT_BSS;
segs[segments].load_addr =
(uint64_t)htonll(phdr[i].p_paddr);
segs[segments].mem_len =
(uint32_t)htonl(phdr[i].p_memsz);
segs[segments].offset = htonl(doffset);
segments++;
continue;
}
if (phdr[i].p_flags & PF_X)
segs[segments].type = PAYLOAD_SEGMENT_CODE;
else
segs[segments].type = PAYLOAD_SEGMENT_DATA;
segs[segments].load_addr = (uint64_t)htonll(phdr[i].p_paddr);
segs[segments].mem_len = (uint32_t)htonl(phdr[i].p_memsz);
segs[segments].compression = htonl(algo);
segs[segments].offset = htonl(doffset);
int len;
compress((char *)&header[phdr[i].p_offset],
phdr[i].p_filesz, (char *)(sptr + doffset), &len);
segs[segments].len = htonl(len);
/* If the compressed section is larger, then use the
original stuff */
if ((unsigned int)len > phdr[i].p_filesz) {
segs[segments].compression = 0;
segs[segments].len = htonl(phdr[i].p_filesz);
memcpy((char *)(sptr + doffset),
&header[phdr[i].p_offset], phdr[i].p_filesz);
}
doffset += ntohl(segs[segments].len);
osize += ntohl(segs[segments].len);
segments++;
}
segs[segments].type = PAYLOAD_SEGMENT_ENTRY;
segs[segments++].load_addr = (uint64_t)htonll(ehdr->e_entry);
*output = sptr;
return (segments * sizeof(struct cbfs_payload_segment)) + osize;
err:
return -1;
}
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