u-boot/tools/dumpimage.c
Guilherme Maciel Ferreira a804b5ce2d Add dumpimage, a tool to extract data from U-Boot images
Given a multi-file image created through the mkimage's -d option:

  $ mkimage -A x86 -O linux -T multi -n x86 -d vmlinuz:initrd.img:System.map \
  multi.img

  Image Name:   x86
  Created:      Thu Jul 25 10:29:13 2013
  Image Type:   Intel x86 Linux Multi-File Image (gzip compressed)
  Data Size:    13722956 Bytes = 13401.32 kB = 13.09 MB
  Load Address: 00000000
  Entry Point:  00000000
  Contents:
     Image 0: 4040128 Bytes = 3945.44 kB = 3.85 MB
     Image 1: 7991719 Bytes = 7804.41 kB = 7.62 MB
     Image 2: 1691092 Bytes = 1651.46 kB = 1.61 MB

It is possible to perform the innverse operation -- extracting any file from
the image -- by using the dumpimage's -i option:

  $ dumpimage -i multi.img -p 2 System.map

Although it's feasible to retrieve "data files" from image through scripting,
the requirement to embed tools such 'dd', 'awk' and 'sed' for this sole purpose
is cumbersome and unreliable -- once you must keep track of file sizes inside
the image. Furthermore, extracting data files using "dumpimage" tool is faster
than through scripting.

Signed-off-by: Guilherme Maciel Ferreira <guilherme.maciel.ferreira@gmail.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
2013-12-13 09:15:32 -05:00

305 lines
7.3 KiB
C

/*
* Based on mkimage.c.
*
* Written by Guilherme Maciel Ferreira <guilherme.maciel.ferreira@gmail.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include "dumpimage.h"
#include <image.h>
#include <version.h>
static void usage(void);
/* image_type_params linked list to maintain registered image types supports */
static struct image_type_params *dumpimage_tparams;
/* parameters initialized by core will be used by the image type code */
static struct image_tool_params params = {
.type = IH_TYPE_KERNEL,
};
/**
* dumpimage_register() - register respective image generation/list support
*
* the input struct image_type_params is checked and appended to the link
* list, if the input structure is already registered, issue an error
*
* @tparams: Image type parameters
*/
static void dumpimage_register(struct image_type_params *tparams)
{
struct image_type_params **tp;
if (!tparams) {
fprintf(stderr, "%s: %s: Null input\n", params.cmdname,
__func__);
exit(EXIT_FAILURE);
}
/* scan the linked list, check for registry and point the last one */
for (tp = &dumpimage_tparams; *tp != NULL; tp = &(*tp)->next) {
if (!strcmp((*tp)->name, tparams->name)) {
fprintf(stderr, "%s: %s already registered\n",
params.cmdname, tparams->name);
return;
}
}
/* add input struct entry at the end of link list */
*tp = tparams;
/* mark input entry as last entry in the link list */
tparams->next = NULL;
debug("Registered %s\n", tparams->name);
}
/**
* dumpimage_get_type() - find the image type params for a given image type
*
* Scan all registered image types and check the input type_id for each
* supported image type
*
* @return respective image_type_params pointer. If the input type is not
* supported by any of registered image types, returns NULL
*/
static struct image_type_params *dumpimage_get_type(int type)
{
struct image_type_params *curr;
for (curr = dumpimage_tparams; curr != NULL; curr = curr->next) {
if (curr->check_image_type) {
if (!curr->check_image_type(type))
return curr;
}
}
return NULL;
}
/*
* dumpimage_verify_print_header() - verifies the image header
*
* Scan registered image types and verify the image_header for each
* supported image type. If verification is successful, this prints
* the respective header.
*
* @return 0 on success, negative if input image format does not match with
* any of supported image types
*/
static int dumpimage_verify_print_header(void *ptr, struct stat *sbuf)
{
int retval = -1;
struct image_type_params *curr;
for (curr = dumpimage_tparams; curr != NULL; curr = curr->next) {
if (curr->verify_header) {
retval = curr->verify_header((unsigned char *)ptr,
sbuf->st_size, &params);
if (retval != 0)
continue;
/*
* Print the image information if verify is
* successful
*/
if (curr->print_header) {
curr->print_header(ptr);
} else {
fprintf(stderr,
"%s: print_header undefined for %s\n",
params.cmdname, curr->name);
}
break;
}
}
return retval;
}
/*
* dumpimage_extract_datafile -
*
* It scans all registered image types,
* verifies image_header for each supported image type
* if verification is successful, it extracts the desired file,
* indexed by pflag, from the image
*
* returns negative if input image format does not match with any of
* supported image types
*/
static int dumpimage_extract_datafile(void *ptr, struct stat *sbuf)
{
int retval = -1;
struct image_type_params *curr;
for (curr = dumpimage_tparams; curr != NULL; curr = curr->next) {
if (curr->verify_header) {
retval = curr->verify_header((unsigned char *)ptr,
sbuf->st_size, &params);
if (retval != 0)
continue;
/*
* Extract the file from the image
* if verify is successful
*/
if (curr->extract_datafile) {
curr->extract_datafile(ptr, &params);
} else {
fprintf(stderr,
"%s: extract_datafile undefined for %s\n",
params.cmdname, curr->name);
break;
}
}
}
return retval;
}
int main(int argc, char **argv)
{
int opt;
int ifd = -1;
struct stat sbuf;
char *ptr;
int retval = 0;
struct image_type_params *tparams = NULL;
/* Init all image generation/list support */
register_image_tool(dumpimage_register);
params.cmdname = *argv;
while ((opt = getopt(argc, argv, "li:o:p:V")) != -1) {
switch (opt) {
case 'l':
params.lflag = 1;
break;
case 'i':
params.imagefile = optarg;
params.iflag = 1;
break;
case 'o':
params.outfile = optarg;
break;
case 'p':
params.pflag = strtoul(optarg, &ptr, 10);
if (*ptr) {
fprintf(stderr,
"%s: invalid file position %s\n",
params.cmdname, *argv);
exit(EXIT_FAILURE);
}
break;
case 'V':
printf("dumpimage version %s\n", PLAIN_VERSION);
exit(EXIT_SUCCESS);
default:
usage();
}
}
if (optind >= argc)
usage();
/* set tparams as per input type_id */
tparams = dumpimage_get_type(params.type);
if (tparams == NULL) {
fprintf(stderr, "%s: unsupported type %s\n",
params.cmdname, genimg_get_type_name(params.type));
exit(EXIT_FAILURE);
}
/*
* check the passed arguments parameters meets the requirements
* as per image type to be generated/listed
*/
if (tparams->check_params) {
if (tparams->check_params(&params))
usage();
}
if (params.iflag)
params.datafile = argv[optind];
else
params.imagefile = argv[optind];
if (!params.outfile)
params.outfile = params.datafile;
ifd = open(params.imagefile, O_RDONLY|O_BINARY);
if (ifd < 0) {
fprintf(stderr, "%s: Can't open \"%s\": %s\n",
params.cmdname, params.imagefile,
strerror(errno));
exit(EXIT_FAILURE);
}
if (params.lflag || params.iflag) {
if (fstat(ifd, &sbuf) < 0) {
fprintf(stderr, "%s: Can't stat \"%s\": %s\n",
params.cmdname, params.imagefile,
strerror(errno));
exit(EXIT_FAILURE);
}
if ((unsigned)sbuf.st_size < tparams->header_size) {
fprintf(stderr,
"%s: Bad size: \"%s\" is not valid image\n",
params.cmdname, params.imagefile);
exit(EXIT_FAILURE);
}
ptr = mmap(0, sbuf.st_size, PROT_READ, MAP_SHARED, ifd, 0);
if (ptr == MAP_FAILED) {
fprintf(stderr, "%s: Can't read \"%s\": %s\n",
params.cmdname, params.imagefile,
strerror(errno));
exit(EXIT_FAILURE);
}
/*
* Both calls bellow scan through dumpimage registry for all
* supported image types and verify the input image file
* header for match
*/
if (params.iflag) {
/*
* Extract the data files from within the matched
* image type. Returns the error code if not matched
*/
retval = dumpimage_extract_datafile(ptr, &sbuf);
} else {
/*
* Print the image information for matched image type
* Returns the error code if not matched
*/
retval = dumpimage_verify_print_header(ptr, &sbuf);
}
(void)munmap((void *)ptr, sbuf.st_size);
(void)close(ifd);
return retval;
}
(void)close(ifd);
return EXIT_SUCCESS;
}
static void usage(void)
{
fprintf(stderr, "Usage: %s -l image\n"
" -l ==> list image header information\n",
params.cmdname);
fprintf(stderr,
" %s -i image [-p position] [-o outfile] data_file\n"
" -i ==> extract from the 'image' a specific 'data_file'"
", indexed by 'position' (starting at 0)\n",
params.cmdname);
fprintf(stderr,
" %s -V ==> print version information and exit\n",
params.cmdname);
exit(EXIT_FAILURE);
}