Improved size estimation and property assessment of El Torito hidden boot images

This commit is contained in:
Thomas Schmitt 2023-11-20 11:42:41 +01:00
parent 8a8439768c
commit 405f0f04d4

View File

@ -1,6 +1,6 @@
/*
* Copyright (c) 2007 Vreixo Formoso
* Copyright (c) 2009 - 2022 Thomas Schmitt
* Copyright (c) 2009 - 2023 Thomas Schmitt
*
* This file is part of the libisofs project; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version 2
@ -550,6 +550,10 @@ struct image_fs_data
};
static int iso_impsysa_reduce_next_above(IsoImage *image, uint32_t block,
uint32_t *next_above, int flag);
struct child_list
{
IsoFileSource *file;
@ -3598,6 +3602,8 @@ int create_boot_img_filesrc(IsoImageFilesystem *fs, IsoImage *image, int idx,
_ImageFsData *fsdata;
IsoFileSource *ifsrc = NULL;
ImageFileSourceData *ifsdata = NULL;
IsoNode *node;
uint32_t size, next_above = 0, start_block;
if (fs == NULL || fs->data == NULL || src == NULL) {
return ISO_NULL_POINTER;
@ -3611,12 +3617,32 @@ int create_boot_img_filesrc(IsoImageFilesystem *fs, IsoImage *image, int idx,
atts.st_nlink = 1;
/*
* Old comment from Vreixo Formoso:
* this is the greater problem. We don't know the size. For now, we
* just use a single block of data. In a future, maybe we could figure out
* a better idea. Another alternative is to use several blocks, that way
* is less probable that we throw out valid data.
*/
atts.st_size = (off_t)BLOCK_SIZE;
/* ts C31112 : Make use of size estimation "El Torito img blks :" */
/* (Code from iso_impsysa_report_blockpath() ) */
size = 1;
start_block = fsdata->bootblocks[idx];
iso_tree_get_node_of_block(image, NULL, start_block, &node, &next_above,
0);
ret = iso_impsysa_reduce_next_above(image, start_block, &next_above, 0);
if (ret >= 0) {
if (next_above != 0) {
/* It has to fit in a single extent */
if ((off_t) (next_above - start_block) * BLOCK_SIZE <
(off_t) 0xffffffff) {
size = next_above - start_block;
} else {
size = 0xffffffff / BLOCK_SIZE;
}
}
}
atts.st_size = (off_t) size * BLOCK_SIZE;
/* Fill last entries */
atts.st_dev = fsdata->id;
@ -3648,7 +3674,7 @@ int create_boot_img_filesrc(IsoImageFilesystem *fs, IsoImage *image, int idx,
ifsdata->info = atts;
ifsdata->name = NULL;
ifsdata->sections[0].block = fsdata->bootblocks[idx];
ifsdata->sections[0].size = BLOCK_SIZE;
ifsdata->sections[0].size = size * BLOCK_SIZE;
ifsdata->nsections = 1;
ifsrc->class = &ifs_class;
@ -3665,7 +3691,7 @@ boot_fs_cleanup: ;
}
/** ??? >>> ts B00428 : should the max size become public ? */
#define Libisofs_boot_image_max_sizE (4096*1024)
#define Libisofs_boot_info_image_max_sizE (4096*1024)
/** Guess which of the loaded boot images contain boot information tables.
Set boot->seems_boot_info_table accordingly.
@ -3693,7 +3719,7 @@ int iso_image_eval_boot_info_table(IsoImage *image, struct iso_read_opts *opts,
boot->seems_grub2_boot_info = 0;
boot->seems_isohybrid_capable = 0;
img_size = iso_file_get_size(boot_file);
if (img_size > Libisofs_boot_image_max_sizE || img_size < 64)
if (img_size > Libisofs_boot_info_image_max_sizE || img_size < 64)
continue;
img_lba = 0;
sections = NULL;
@ -4112,6 +4138,8 @@ ex:;
return ret;
}
/* @param flag bit0= Pre-run: Only assess partition table.
*/
static
int iso_analyze_mbr(IsoImage *image, IsoDataSource *src, int flag)
{
@ -4134,6 +4162,11 @@ int iso_analyze_mbr(IsoImage *image, IsoDataSource *src, int flag)
if (ret <= 0)
goto ex;
if((flag & 1)) {
ret= 1;
goto ex;
}
ret = iso_analyze_isohybrid(image, 0);
if (ret < 0)
goto ex;
@ -4443,6 +4476,9 @@ ex:
return ret;
}
/* @param flag bit0= Pre-run: Only assess partition table.
(Yet without effect, because nothing else is done)
*/
static
int iso_analyze_gpt(IsoImage *image, IsoDataSource *src, int flag)
{
@ -4555,6 +4591,9 @@ int iso_analyze_apm_head(IsoImage *image, IsoDataSource *src, int flag)
return 1;
}
/* @param flag bit0= Pre-run: Only assess partition table.
(Yet without effect, because nothing else is done)
*/
static
int iso_analyze_apm(IsoImage *image, IsoDataSource *src, int flag)
{
@ -4609,6 +4648,8 @@ int iso_analyze_apm(IsoImage *image, IsoDataSource *src, int flag)
return 1;
}
/* @param flag bit0= Pre-run: Only assess partition table.
*/
static
int iso_analyze_mips(IsoImage *image, IsoDataSource *src, int flag)
{
@ -4677,12 +4718,14 @@ int iso_analyze_mips(IsoImage *image, IsoDataSource *src, int flag)
sai->mips_vd_entries[idx]->name[8] = 0;
sai->mips_vd_entries[idx]->boot_block = iso_read_msb(upart + 8, 4);
sai->mips_vd_entries[idx]->boot_bytes = iso_read_msb(upart + 12, 4);
ret = iso_tree_get_node_of_block(image, NULL,
if (!(flag & 1)) {
ret = iso_tree_get_node_of_block(image, NULL,
sai->mips_vd_entries[idx]->boot_block / 4,
&node, NULL, 0);
if (ret > 0)
sai->mips_boot_file_paths[idx] = iso_tree_get_node_path(node);
sai->num_mips_boot_files++;
if (ret > 0)
sai->mips_boot_file_paths[idx] = iso_tree_get_node_path(node);
sai->num_mips_boot_files++;
}
}
if (sai->num_mips_boot_files > 0)
sai->system_area_options = (1 << 2);/* MIPS Big Endian Volume Header */
@ -4690,6 +4733,8 @@ int iso_analyze_mips(IsoImage *image, IsoDataSource *src, int flag)
return ret;
}
/* @param flag bit0= Pre-run: Only assess partition table.
*/
static
int iso_analyze_mipsel(IsoImage *image, IsoDataSource *src, int flag)
{
@ -4717,19 +4762,22 @@ int iso_analyze_mipsel(IsoImage *image, IsoDataSource *src, int flag)
sai->mipsel_e_entry = iso_read_lsb(usad + 20, 4);
sai->mipsel_p_filesz = iso_read_lsb(usad + 24, 4) * 512;
sai->mipsel_seg_start = iso_read_lsb(usad + 28, 4);
ret = iso_tree_get_node_of_block(image, NULL, sai->mipsel_seg_start / 4,
&node, NULL, 0);
if (ret > 0) {
sai->mipsel_boot_file_path = iso_tree_get_node_path(node);
file = (IsoFile *) node;
ret = iso_file_get_old_image_sections(file, &section_count,
&sections, 0);
if (ret > 0 && section_count > 0) {
if (sections[0].block < (1 << 30) &&
sections[0].block * 4 < sai->mipsel_seg_start)
sai->mipsel_p_offset = sai->mipsel_seg_start -
sections[0].block * 4;
free(sections);
if(!(flag & 1)) {
ret = iso_tree_get_node_of_block(image, NULL,
sai->mipsel_seg_start / 4, &node,
NULL, 0);
if (ret > 0) {
sai->mipsel_boot_file_path = iso_tree_get_node_path(node);
file = (IsoFile *) node;
ret = iso_file_get_old_image_sections(file, &section_count,
&sections, 0);
if (ret > 0 && section_count > 0) {
if (sections[0].block < (1 << 30) &&
sections[0].block * 4 < sai->mipsel_seg_start)
sai->mipsel_p_offset = sai->mipsel_seg_start -
sections[0].block * 4;
free(sections);
}
}
}
/* DEC Boot Block for MIPS Little Endian */
@ -4738,6 +4786,8 @@ int iso_analyze_mipsel(IsoImage *image, IsoDataSource *src, int flag)
return 1;
}
/* @param flag bit0= Pre-run: Only assess partition table.
*/
static
int iso_analyze_sun(IsoImage *image, IsoDataSource *src, int flag)
{
@ -4810,7 +4860,8 @@ int iso_analyze_sun(IsoImage *image, IsoDataSource *src, int flag)
sai->sparc_grub2_core_size + 2047) / 2048;
if (last_core_block > 0)
last_core_block--;
if (last_core_block > 17 && last_core_block < sai->image_size) {
if (last_core_block > 17 && last_core_block < sai->image_size &&
!(flag & 1)) {
ret = iso_tree_get_node_of_block(image, NULL,
(uint32_t) last_core_block, &node,
NULL, 0);
@ -4829,6 +4880,8 @@ int iso_analyze_sun(IsoImage *image, IsoDataSource *src, int flag)
return 1;
}
/* @param flag bit0= Pre-run: Only assess partition table.
*/
static
int iso_analyze_hppa(IsoImage *image, IsoDataSource *src, int flag)
{
@ -4870,17 +4923,19 @@ int iso_analyze_hppa(IsoImage *image, IsoDataSource *src, int flag)
sai->hppa_ramdisk_len = iso_read_msb(usad + 20, 4);
adrs[3] = sai->hppa_bootloader_adr = iso_read_msb(usad + 240, 4);
sai->hppa_bootloader_len = iso_read_msb(usad + 244, 4);
for (i = 0; i < 4; i++) {
paths[i] = NULL;
ret = iso_tree_get_node_of_block(image, NULL, adrs[i] / 2048,
&node, NULL, 0);
if (ret > 0)
paths[i] = iso_tree_get_node_path(node);
if(!(flag & 1)) {
for (i = 0; i < 4; i++) {
paths[i] = NULL;
ret = iso_tree_get_node_of_block(image, NULL, adrs[i] / 2048,
&node, NULL, 0);
if (ret > 0)
paths[i] = iso_tree_get_node_path(node);
}
sai->hppa_kernel_32 = paths[0];
sai->hppa_kernel_64 = paths[1];
sai->hppa_ramdisk = paths[2];
sai->hppa_bootloader = paths[3];
}
sai->hppa_kernel_32 = paths[0];
sai->hppa_kernel_64 = paths[1];
sai->hppa_ramdisk = paths[2];
sai->hppa_bootloader = paths[3];
if (sai->hppa_hdrversion == 5)
sai->hppa_ipl_entry = iso_read_msb(usad + 248, 4);
@ -4891,6 +4946,8 @@ int iso_analyze_hppa(IsoImage *image, IsoDataSource *src, int flag)
return 1;
}
/* @param flag bit0= Pre-run: Only assess partition table.
*/
static
int iso_analyze_alpha_boot(IsoImage *image, IsoDataSource *src, int flag)
{
@ -4915,25 +4972,27 @@ int iso_analyze_alpha_boot(IsoImage *image, IsoDataSource *src, int flag)
sai->alpha_boot_image = NULL;
sai->alpha_boot_image_size = (uint64_t) iso_read_lsb64(usad + 480);
sai->alpha_boot_image_adr = (uint64_t) iso_read_lsb64(usad + 488);
ret = iso_tree_get_node_of_block(image, NULL,
if (!(flag & 1)) {
ret = iso_tree_get_node_of_block(image, NULL,
(uint32_t) (sai->alpha_boot_image_adr / 4),
&node, NULL, 0);
if (ret > 0) {
if (iso_node_get_type(node) != LIBISO_FILE)
return 0;
file = (IsoFile *) node;
ret = iso_file_get_old_image_sections(file, &section_count,
&sections, 0);
if (ret > 0 && section_count > 0) {
size = sections[0].size / 512 + !!(sections[0].size % 512);
free(sections);
if (size != sai->alpha_boot_image_size)
return 0;
}
sai->alpha_boot_image = iso_tree_get_node_path(node);
} else if (strncmp(sad, "Linux/Alpha aboot for ISO filesystem.", 37) != 0
|| sad[37] != 0) {
return 0; /* Want to see either boot file or genisoimage string */
if (ret > 0) {
if (iso_node_get_type(node) != LIBISO_FILE)
return 0;
file = (IsoFile *) node;
ret = iso_file_get_old_image_sections(file, &section_count,
&sections, 0);
if (ret > 0 && section_count > 0) {
size = sections[0].size / 512 + !!(sections[0].size % 512);
free(sections);
if (size != sai->alpha_boot_image_size)
return 0;
}
sai->alpha_boot_image = iso_tree_get_node_path(node);
} else if (strncmp(sad, "Linux/Alpha aboot for ISO filesystem.", 37)
!= 0 || sad[37] != 0) {
return 0; /* Want to see either boot file or genisoimage string */
}
}
sai->system_area_options = (6 << 2);
return 1;
@ -5016,6 +5075,8 @@ int iso_impsysa_reduce_next_above(IsoImage *image, uint32_t block,
struct iso_file_section *sections = NULL;
sai = image->imported_sa_info;
if (sai == NULL)
return 0;
/* PVD, path table, root directory of active and of first session */
for (i = 0; i < sai->num_meta_struct_blocks; i++)
@ -5066,7 +5127,7 @@ int iso_impsysa_reduce_next_above(IsoImage *image, uint32_t block,
iso_impsysa_reduce_na(block, next_above, sai->image_size);
return ISO_SUCCESS;
return 1;
}
/* @param flag bit0= try to estimate the size if no path is found
@ -5804,6 +5865,9 @@ ex:
return ret;
}
/* @param flag bit0= Pre-run: Only assess partition tables. Do not refer to
loaded tree or El Torito boot equipment.
*/
static
int iso_analyze_system_area(IsoImage *image, IsoDataSource *src,
struct iso_read_opts *opts, uint32_t image_size,
@ -5825,48 +5889,50 @@ int iso_analyze_system_area(IsoImage *image, IsoDataSource *src,
image->imported_sa_info->image_size = image_size;
image->imported_sa_info->pvd_block = opts->block + 16;
ret = iso_analyze_mbr(image, src, 0);
ret = iso_analyze_mbr(image, src, flag & 1);
if (ret < 0)
goto ex;
ret = iso_analyze_gpt(image, src, 0);
ret = iso_analyze_gpt(image, src, flag & 1);
if (ret < 0)
goto ex;
ret = iso_analyze_apm(image, src, 0);
ret = iso_analyze_apm(image, src, flag & 1);
if (ret < 0)
goto ex;
sao = image->imported_sa_info->system_area_options;
sa_type = (sao >> 2) & 0x3f;
sa_sub = (sao >> 10) & 0xf;
if (sa_type == 0 && !((sao & 3) || sa_sub == 1 || sa_sub == 2)) {
ret = iso_analyze_mips(image, src, 0);
ret = iso_analyze_mips(image, src, flag & 1);
if (ret < 0)
goto ex;
if (ret == 0) {
ret = iso_analyze_mipsel(image, src, 0);
ret = iso_analyze_mipsel(image, src, flag & 1);
if (ret < 0)
goto ex;
}
if (ret == 0) {
ret = iso_analyze_sun(image, src, 0);
ret = iso_analyze_sun(image, src, flag & 1);
if (ret < 0)
goto ex;
}
}
if (sa_type == 0 && !((sao & 3) || sa_sub == 1)) {
/* HP-PA PALO v5 can look like generic MBR */
ret = iso_analyze_hppa(image, src, 0);
ret = iso_analyze_hppa(image, src, flag & 1);
if (ret < 0)
goto ex;
/* DEC Alpha has checksum bytes where MBR has its magic number */
if (ret == 0) {
ret = iso_analyze_alpha_boot(image, src, 0);
ret = iso_analyze_alpha_boot(image, src, flag & 1);
if (ret < 0)
goto ex;
}
}
ret = iso_record_meta_struct_blocks(image, src, 0);
if (ret < 0)
goto ex;
if (!(flag & 1)) {
ret = iso_record_meta_struct_blocks(image, src, 0);
if (ret < 0)
goto ex;
}
ret = ISO_SUCCESS;
ex:;
@ -6392,6 +6458,7 @@ int iso_image_import(IsoImage *image, IsoDataSource *src,
int features_allocated = 0;
static char *tree_loaded_names[3]= {"ISO9660", "Joliet", "ISO9660:1999"};
int root_has_aaip = 0, rrip_version_1_10;
unsigned long img_size;
if (image == NULL || src == NULL || opts == NULL) {
return ISO_NULL_POINTER;
@ -6546,6 +6613,27 @@ int iso_image_import(IsoImage *image, IsoDataSource *src,
}
}
/* Pre-assessment of System Area because image->imported_sa_info with
assessed partitions is needed in create_boot_img_filesrc().
Nevertheless, some properties can only be determined later, when
other image properties have been assessed. So there will be another
run of iso_analyze_system_area() without flag bit0 when more of the
imported image is known.
*/
if (opts->load_system_area && image->system_area_data != NULL &&
!(opts->read_features & 4)) {
/* Preliminary assessment. Not complete because some aspects of the
filesystem have not been loaded yet.
*/
ret = iso_analyze_system_area(image, src, opts, data->nblocks, 1);
if (ret < 0) {
iso_msg_submit(-1, ISO_SYSAREA_PROBLEMS, 0,
"Problem encountered during inspection of System Area:");
iso_msg_submit(-1, ISO_SYSAREA_PROBLEMS, 0,
iso_error_to_msg(ret));
}
}
/* if old image has el-torito, add a new catalog */
if (data->eltorito) {
@ -6668,20 +6756,28 @@ int iso_image_import(IsoImage *image, IsoDataSource *src,
/* warn about hidden images */
if (!(opts->read_features & 4)) {
img_size = iso_file_get_size((IsoFile *) node);
if (image->bootcat->bootimages[idx]->platform_id == 0xef) {
iso_msg_submit(image->id, ISO_ELTO_EFI_HIDDEN, 0,
"Found hidden El-Torito image for EFI.");
iso_msg_submit(image->id, ISO_GENERAL_NOTE, 0,
"EFI image start and size: %lu * 2048 , %lu * 512",
"EFI image start and load size: %lu * 2048 , %lu * 512",
(unsigned long int)
image->bootcat->bootimages[idx]->appended_start,
(unsigned long int)
image->bootcat->bootimages[idx]->load_size);
iso_msg_submit(image->id, ISO_GENERAL_NOTE, 0,
"Roughly estimated EFI image size: %lu bytes",
img_size);
} else {
iso_msg_submit(image->id, ISO_EL_TORITO_HIDDEN, 0,
"Found hidden El-Torito image. Its size could not "
"be figured out, so image modify or boot image "
"patching may lead to bad results.");
"Found hidden El-Torito image for Non-EFI platform.",
img_size);
iso_msg_submit(image->id, ISO_EL_TORITO_HIDDEN, 0,
"Roughly estimated image size: %lu bytes",
img_size);
iso_msg_submit(image->id, ISO_EL_TORITO_HIDDEN, 0,
"Image modification or boot image patching may lead to bad results.");
}
}
}
@ -6926,6 +7022,9 @@ int iso_image_import(IsoImage *image, IsoDataSource *src,
if (ret < 0)
goto import_revert;
/* Second run of iso_analyze_system_area() after El Torito equipment and
file tree have been assessed
*/
if (opts->load_system_area && image->system_area_data != NULL &&
!(opts->read_features & 4)) {
ret = iso_analyze_system_area(image, src, opts, data->nblocks, 0);