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/*
* cbfs-mkstage
*
* Copyright (C) 2008 Jordan Crouse <jordan@cosmicpenguin.net>
*
* 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"
unsigned int idemp(unsigned int x)
{
return x;
}
unsigned int swap32(unsigned int x)
{
return ((x>>24) | ((x>>8) & 0xff00) | ((x<<8) & 0xff0000) | (x<<24));
}
unsigned int (*elf32_to_native)(unsigned int)=idemp;
int parse_elf(unsigned char *input, unsigned char **output,
int mode, void (*compress) (char *, int, char *, int *))
{
Elf32_Phdr *phdr;
Elf32_Ehdr *ehdr = (Elf32_Ehdr *) input;
char *header, *buffer;
unsigned char *out;
int headers;
int i;
struct cbfs_stage *stage;
unsigned int data_start, data_end, mem_end;
int elf_bigendian = 0;
int host_bigendian = 0;
if (ehdr->e_ident[EI_DATA]==ELFDATA2MSB) {
elf_bigendian = 1;
}
if ((unsigned int)"1234"==0x31323334) {
host_bigendian = 1;
}
if (elf_bigendian != host_bigendian) {
elf32_to_native = swap32;
}
headers = ehdr->e_phnum;
header = (char *)ehdr;
phdr = (Elf32_Phdr *) & header[elf32_to_native(ehdr->e_phoff)];
/* Now, regular headers - we only care about PT_LOAD headers,
* because thats what we're actually going to load
*/
data_start = 0xFFFFFFFF;
data_end = 0;
mem_end = 0;
for (i = 0; i < headers; i++) {
unsigned int start, mend, rend;
if (elf32_to_native(phdr[i].p_type) != PT_LOAD)
continue;
/* Empty segments are never interesting */
if (elf32_to_native(phdr[i].p_memsz) == 0)
continue;
/* BSS */
start = elf32_to_native(phdr[i].p_paddr);
mend = start + elf32_to_native(phdr[i].p_memsz);
rend = start + elf32_to_native(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;
}
/* allocate an intermediate buffer for the data */
buffer = calloc(data_end - data_start, 1);
if (buffer == NULL) {
fprintf(stderr, "E: Unable to allocate memory: %m\n");
return -1;
}
/* Copy the file data into the buffer */
for (i = 0; i < headers; i++) {
if (elf32_to_native(phdr[i].p_type) != PT_LOAD)
continue;
if (elf32_to_native(phdr[i].p_memsz) == 0)
continue;
memcpy(buffer + (elf32_to_native(phdr[i].p_paddr) - data_start),
&header[elf32_to_native(phdr[i].p_offset)], elf32_to_native(phdr[i].p_filesz));
}
/* Now make the output buffer */
out = calloc(sizeof(struct cbfs_stage) + data_end - data_start, 1);
if (out == NULL) {
fprintf(stderr, "E: Unable to allocate memory: %m\n");
return -1;
}
stage = (struct cbfs_stage *)out;
stage->load = data_start;
stage->memlen = mem_end - data_start;
stage->compression = mode;
stage->entry = ehdr->e_entry;
compress(buffer, data_end - data_start,
(char *)(out + sizeof(struct cbfs_stage)),
(int *)&stage->len);
*output = out;
return sizeof(struct cbfs_stage) + stage->len;
}
int main(int argc, char **argv)
{
void (*compress) (char *, int, char *, int *);
int algo = CBFS_COMPRESS_LZMA;
char *output = NULL;
char *input = NULL;
unsigned char *buffer, *obuffer;
int size, osize;
while (1) {
int option_index;
static struct option longopt[] = {
{"output", 1, 0, 'o'},
{"lzma", 0, 0, 'l'},
{"nocompress", 0, 0, 'n'},
};
signed char ch = getopt_long(argc, argv, "o:ln",
longopt, &option_index);
if (ch == -1)
break;
switch (ch) {
case 'o':
output = optarg;
break;
case 'l':
algo = CBFS_COMPRESS_LZMA;
break;
case 'n':
algo = CBFS_COMPRESS_NONE;
break;
default:
//usage();
return -1;
}
}
if (optind < argc)
input = argv[optind];
if (input == NULL || !strcmp(input, "-"))
buffer = file_read_to_buffer(STDIN_FILENO, &size);
else
buffer = file_read(input, &size);
if (!iself(buffer)) {
fprintf(stderr, "E: The incoming file is not an ELF\n");
return -1;
}
switch (algo) {
case CBFS_COMPRESS_NONE:
compress = none_compress;
break;
case CBFS_COMPRESS_LZMA:
compress = lzma_compress;
break;
}
osize = parse_elf(buffer, &obuffer, algo, compress);
if (osize == -1) {
fprintf(stderr, "E: Error while converting the ELF\n");
return -1;
}
if (output == NULL || !strcmp(output, "-"))
file_write_from_buffer(STDOUT_FILENO, obuffer, osize);
else
file_write(output, obuffer, osize);
return 0;
}
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