First cut support for extracting from ISO9660 disk images.

This seems to be able to extract a TOC and extract files from
the couple of ISO images I've tested it with.

Treat this as experimental proof-of-concept code for the
moment.  There are still a bunch of debug messages (there
are a few oddities in ISO9660 that I haven't yet figured
out how to handle), a lot of bugs to be addressed (this
code leaks memory very badly), and a lot of missing features (no
Rockridge support, in particular).  I'd appreciate
feedback from anyone who understands ISO9660 format
better than I do. ;-)

Suggested by: Robert Watson
This commit is contained in:
Tim Kientzle 2005-01-02 05:21:15 +00:00
parent 5d3ec186d5
commit 5d9e84da87
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=139565
3 changed files with 524 additions and 1 deletions

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@ -7,7 +7,7 @@
LIB= archive
VERSION= 1.01.015
VERSION= 1.01.022
ARCHIVE_API_FEATURE= 2
ARCHIVE_API_VERSION= 1
SHLIB_MAJOR= ${ARCHIVE_API_VERSION}
@ -40,6 +40,7 @@ SRCS= archive.h \
archive_read_support_compression_none.c \
archive_read_support_format_all.c \
archive_read_support_format_cpio.c \
archive_read_support_format_iso9660.c \
archive_read_support_format_tar.c \
archive_string.c \
archive_string_sprintf.c \

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@ -159,6 +159,7 @@ int archive_read_support_compression_none(struct archive *);
int archive_read_support_format_all(struct archive *);
int archive_read_support_format_cpio(struct archive *);
int archive_read_support_format_gnutar(struct archive *);
int archive_read_support_format_iso9660(struct archive *);
int archive_read_support_format_tar(struct archive *);

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@ -0,0 +1,521 @@
/*-
* Copyright (c) 2003-2004 Tim Kientzle
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer
* in this position and unchanged.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "archive_platform.h"
__FBSDID("$FreeBSD$");
#include <sys/stat.h>
#include <errno.h>
/* #include <stdint.h> */ /* See archive_platform.h */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "archive.h"
#include "archive_entry.h"
#include "archive_private.h"
#include "archive_string.h"
/*
* An overview of ISO 9660 format:
*
* Each disk is laid out as follows:
* * 32k reserved for private use
* * Volume descriptor table. Each volume descriptor
* is 2k and specifies basic format information.
* The "Primary Volume Descriptor" (PVD) is defined by the
* standard and should always be present; other volume
* descriptors include various vendor-specific extensions.
* * Files and directories. Each file/dir is specified by
* an "extent" (starting sector and length in bytes).
* Dirs are just files with directory records packed one
* after another. The PVD contains a single dir entry
* specifying the location of the root directory. Everything
* else follows from there.
*
* This module works by first reading the volume descriptors, then
* building a heap of directory entries, sorted by starting
* sector. At each step, I look for the earliest dir entry that
* hasn't yet been read, seek forward to that location and read
* that entry. If it's a dir, I slurp in the new dir entries and
* add them to the heap; if it's a regular file, I return the
* corresponding archive_entry and wait for the client to request
* the file body. This strategy allows us to read most compliant
* CDs with a single pass through the data, as required by libarchive.
*/
/* Structure of on-disk PVD. */
struct primary_volume_descriptor {
unsigned char type[1];
char id[5];
unsigned char version[1];
char reserved1[1];
char system_id[32];
char volume_id[32];
char reserved2[8];
char volume_space_size[8];
char reserved3[32];
char volume_set_size[4];
char volume_sequence_number[4];
char logical_block_size[4];
char path_table_size[8];
char type_1_path_table[4];
char opt_type_1_path_table[4];
char type_m_path_table[4];
char opt_type_m_path_table[4];
char root_directory_record[34];
char volume_set_id[128];
char publisher_id[128];
char preparer_id[128];
char application_id[128];
char copyright_file_id[37];
char abstract_file_id[37];
char bibliographic_file_id[37];
char creation_date[17];
char modification_date[17];
char expiration_date[17];
char effective_date[17];
char file_structure_version[1];
char reserved4[1];
char application_data[512];
};
/* Structure of an on-disk directory record. */
struct directory_record {
unsigned char length[1];
unsigned char ext_attr_length[1];
unsigned char extent[8];
unsigned char size[8];
char date[7];
unsigned char flags[1];
unsigned char file_unit_size[1];
unsigned char interleave[1];
unsigned char volume_sequence_number[4];
unsigned char name_len[1];
char name[1];
};
/*
* Our private data.
*/
/* In-memory storage for a directory record. */
struct dir_rec {
struct dir_rec *parent;
unsigned char flags;
uint64_t offset; /* Offset on disk. */
uint64_t size; /* File size in bytes. */
time_t mtime; /* File last modified time. */
char name[1]; /* Null-terminated filename. */
};
struct iso9660 {
int magic;
#define ISO9660_MAGIC 0x96609660
int bid; /* If non-zero, return this as our bid. */
struct archive_string pathname;
/* TODO: Make this a heap for fast inserts and deletions. */
struct dir_rec **pending_files;
int pending_files_allocated;
int pending_files_used;
uint64_t current_position;
ssize_t logical_block_size;
off_t entry_offset;
ssize_t entry_padding;
ssize_t entry_bytes_remaining;
};
static int archive_read_format_iso9660_bid(struct archive *);
static int archive_read_format_iso9660_cleanup(struct archive *);
static int archive_read_format_iso9660_read_data(struct archive *,
const void **, size_t *, off_t *);
static int archive_read_format_iso9660_read_header(struct archive *,
struct archive_entry *);
static const char *build_pathname(struct archive_string *, struct dir_rec *);
static time_t isodate(const void *);
static int isPVD(struct iso9660 *, const char *);
static struct dir_rec *next_entry(struct iso9660 *);
static int store_pending(struct iso9660 *, struct dir_rec *parent,
const struct directory_record *);
static int toi(const void *p, int n);
int
archive_read_support_format_iso9660(struct archive *a)
{
struct iso9660 *iso9660;
int r;
iso9660 = malloc(sizeof(*iso9660));
memset(iso9660, 0, sizeof(*iso9660));
iso9660->magic = ISO9660_MAGIC;
iso9660->bid = -1; /* We haven't yet bid. */
r = __archive_read_register_format(a,
iso9660,
archive_read_format_iso9660_bid,
archive_read_format_iso9660_read_header,
archive_read_format_iso9660_read_data,
archive_read_format_iso9660_cleanup);
if (r != ARCHIVE_OK) {
free(iso9660);
return (r);
}
return (ARCHIVE_OK);
}
static int
archive_read_format_iso9660_bid(struct archive *a)
{
struct iso9660 *iso9660;
ssize_t bytes_read;
const void *h;
const char *p;
iso9660 = *(a->pformat_data);
if (iso9660->bid >= 0)
return (iso9660->bid);
/*
* Skip the first 32k (reserved area) and get the first
* 8 sectors of the volume descriptor table. Of course,
* if the I/O layer gives us more, we'll take it.
*/
bytes_read = (a->compression_read_ahead)(a, &h, 32768 + 8*2048);
if (bytes_read < 32768 + 8*2048)
return (iso9660->bid = -1);
p = (const char *)h;
/* Skip the reserved area. */
bytes_read -= 32768;
p += 32768;
/* Check each volume descriptor to locate the PVD. */
for (; bytes_read > 2048; bytes_read -= 2048, p += 2048) {
iso9660->bid = isPVD(iso9660, p);
if (iso9660->bid > 0)
return (iso9660->bid);
}
/* We didn't find a valid PVD; return a bid of zero. */
iso9660->bid = 0;
return (iso9660->bid);
}
static int
isPVD(struct iso9660 *iso9660, const char *h)
{
const struct primary_volume_descriptor *voldesc;
if (h[0] != 1)
return (0);
if (memcmp(h+1, "CD001", 5) != 0)
return (0);
voldesc = (const struct primary_volume_descriptor *)h;
iso9660->logical_block_size = toi(&voldesc->logical_block_size, 2);
/* Store the root directory in the pending list. */
store_pending(iso9660, NULL,
(struct directory_record *)&voldesc->root_directory_record);
return (48);
}
static int
archive_read_format_iso9660_read_header(struct archive *a,
struct archive_entry *entry)
{
struct stat st;
struct iso9660 *iso9660;
struct dir_rec *dirrec;
ssize_t bytes_read;
const void *buff;
iso9660 = *(a->pformat_data);
/* Get the next entry that appears after the current offset. */
dirrec = next_entry(iso9660);
if (dirrec == NULL)
return (ARCHIVE_EOF);
while (dirrec->offset < iso9660->current_position) {
archive_string_empty(&iso9660->pathname);
fprintf(stderr, "\n ** Ignoring out-of-order file `%s' (offset 0x%0x/size %d) current offset 0x%x\n", build_pathname(&iso9660->pathname, dirrec), (unsigned int)dirrec->offset, (int)dirrec->size, (unsigned int)iso9660->current_position);
dirrec = next_entry(iso9660);
if (dirrec == NULL)
return (ARCHIVE_EOF);
}
/* Seek forward to the start of that entry. */
while (iso9660->current_position < dirrec->offset) {
ssize_t step = dirrec->offset - iso9660->current_position;
if (step > iso9660->logical_block_size)
step = iso9660->logical_block_size;
bytes_read = (a->compression_read_ahead)(a, &buff, step);
if (bytes_read <= 0)
return (ARCHIVE_FATAL);
if (bytes_read > step)
bytes_read = step;
iso9660->current_position += bytes_read;
(a->compression_read_consume)(a, bytes_read);
}
/* Set up the entry structure with information about this entry. */
memset(&st, 0, sizeof(st));
iso9660->entry_bytes_remaining = dirrec->size;
/* The following assumes the logical block size is a power of 2. */
iso9660->entry_padding = (iso9660->logical_block_size - 1 )
& (-iso9660->entry_bytes_remaining);
iso9660->entry_offset = 0;
st.st_mode = 0444;
if (dirrec->flags & 0x02)
st.st_mode |= S_IFDIR;
else
st.st_mode |= S_IFREG;
st.st_mtime = dirrec->mtime;
st.st_size = iso9660->entry_bytes_remaining;
archive_entry_copy_stat(entry, &st);
archive_string_empty(&iso9660->pathname);
archive_entry_set_pathname(entry,
build_pathname(&iso9660->pathname, dirrec));
/* If this is a directory, read in all of the entries right now. */
if (S_ISDIR(st.st_mode)) {
while(iso9660->entry_bytes_remaining > 0) {
const void *block;
const char *p;
ssize_t step = iso9660->logical_block_size;
if (step > iso9660->entry_bytes_remaining)
step = iso9660->entry_bytes_remaining;
bytes_read = (a->compression_read_ahead)(a, &block, step);
if (bytes_read < step) {
archive_set_error(a, -1,
"Failed to read full block when scanning ISO9660 directory list");
return (ARCHIVE_FATAL);
}
if (bytes_read > step)
bytes_read = step;
if (bytes_read > iso9660->entry_bytes_remaining)
bytes_read = iso9660->entry_bytes_remaining;
(a->compression_read_consume)(a, bytes_read);
iso9660->current_position += bytes_read;
iso9660->entry_bytes_remaining -= bytes_read;
for (p = block; *p != 0; p += *p) {
const struct directory_record *dr
= (const struct directory_record *)p;
/* Skip '.' entry. */
if (dr->name_len[0] == 1
&& dr->name[0] == '\0')
continue;
/* Skip '..' entry. */
if (dr->name_len[0] == 1
&& dr->name[0] == '\001')
continue;
store_pending(iso9660, dirrec, dr);
}
}
}
return (ARCHIVE_OK);
}
static int
archive_read_format_iso9660_read_data(struct archive *a,
const void **buff, size_t *size, off_t *offset)
{
ssize_t bytes_read;
struct iso9660 *iso9660;
iso9660 = *(a->pformat_data);
if (iso9660->entry_bytes_remaining > 0) {
bytes_read = (a->compression_read_ahead)(a, buff, 1);
if (bytes_read <= 0)
return (ARCHIVE_FATAL);
if (bytes_read > iso9660->entry_bytes_remaining)
bytes_read = iso9660->entry_bytes_remaining;
*size = bytes_read;
*offset = iso9660->entry_offset;
iso9660->entry_offset += bytes_read;
iso9660->entry_bytes_remaining -= bytes_read;
iso9660->current_position += bytes_read;
(a->compression_read_consume)(a, bytes_read);
return (ARCHIVE_OK);
} else {
while (iso9660->entry_padding > 0) {
bytes_read = (a->compression_read_ahead)(a, buff, 1);
if (bytes_read <= 0)
return (ARCHIVE_FATAL);
if (bytes_read > iso9660->entry_padding)
bytes_read = iso9660->entry_padding;
iso9660->current_position += bytes_read;
(a->compression_read_consume)(a, bytes_read);
iso9660->entry_padding -= bytes_read;
}
*buff = NULL;
*size = 0;
*offset = iso9660->entry_offset;
return (ARCHIVE_EOF);
}
}
static int
archive_read_format_iso9660_cleanup(struct archive *a)
{
struct iso9660 *iso9660;
iso9660 = *(a->pformat_data);
free(iso9660);
*(a->pformat_data) = NULL;
return (ARCHIVE_OK);
}
static int
store_pending(struct iso9660 *iso9660, struct dir_rec *parent,
const struct directory_record *isodirent)
{
struct dir_rec *new_dirent;
if (iso9660->pending_files_used >= iso9660->pending_files_allocated) {
struct dir_rec **new_pending_files;
int new_size = iso9660->pending_files_allocated * 2;
if (new_size < 1024)
new_size = 1024;
new_pending_files = malloc(new_size * sizeof(new_pending_files[0]));
memcpy(new_pending_files, iso9660->pending_files,
iso9660->pending_files_allocated * sizeof(new_pending_files[0]));
if (iso9660->pending_files != NULL)
free(iso9660->pending_files);
iso9660->pending_files = new_pending_files;
iso9660->pending_files_allocated = new_size;
}
new_dirent = malloc(sizeof(*new_dirent) + isodirent->name_len[0] + 1);
new_dirent->parent = parent;
new_dirent->flags = isodirent->flags[0];
new_dirent->offset = toi(isodirent->extent, 4)
* iso9660->logical_block_size;
new_dirent->size = toi(isodirent->size, 4);
new_dirent->mtime = isodate(isodirent->date);
memcpy(new_dirent->name, isodirent->name, isodirent->name_len[0]);
new_dirent->name[(int)isodirent->name_len[0]] = '\0';
iso9660->pending_files[iso9660->pending_files_used++] = new_dirent;
/* DEBUGGING */
if ((isodirent->flags[0] & ~0x02) != 0) {
archive_string_empty(&iso9660->pathname);
fprintf(stderr, "\n ** Unrecognized flag 0x%x in file %s\n",
new_dirent->flags,
build_pathname(&iso9660->pathname, new_dirent));
}
if (toi(isodirent->volume_sequence_number,2) != 1
|| isodirent->file_unit_size[0] != 0
|| isodirent->interleave[0] != 0
|| isodirent->ext_attr_length[0] != 0) {
fprintf(stderr, "\n ** Unhandled ISO9660 directory attribute:");
fprintf(stderr, " l %d, a %d, ext 0x%x, s %d, f 0x%02x, unt %d, ilv %d, seq %d: `%.*s' (%d)\n", isodirent->length[0], isodirent->ext_attr_length[0], toi(isodirent->extent, 4) * 2048, toi(isodirent->size, 4), isodirent->flags[0], isodirent->file_unit_size[0], isodirent->interleave[0], toi(isodirent->volume_sequence_number,2), isodirent->name_len[0], isodirent->name, isodirent->name_len[0]);
}
return (ARCHIVE_OK);
}
static struct dir_rec *
next_entry(struct iso9660 *iso9660)
{
int least_index = 0;
uint64_t least_offset = iso9660->pending_files[0]->offset;
int i;
struct dir_rec *r;
if (iso9660->pending_files_used < 1)
return (NULL);
for(i = 0; i < iso9660->pending_files_used; i++) {
if (iso9660->pending_files[i]->offset < least_offset) {
least_offset = iso9660->pending_files[i]->offset;
least_index = i;
}
}
r = iso9660->pending_files[least_index];
iso9660->pending_files[least_index]
= iso9660->pending_files[--iso9660->pending_files_used];
return (r);
}
static int
toi(const void *p, int n)
{
const unsigned char *v = (const unsigned char *)p;
if (n > 1)
return v[0] + 256 * toi(v + 1, n - 1);
if (n == 1)
return v[0];
return (0);
}
static time_t
isodate(const void *p)
{
struct tm tm;
const unsigned char *v = (const unsigned char *)p;
int offset;
tm.tm_year = v[0];
tm.tm_mon = v[1] - 1;
tm.tm_mday = v[2];
tm.tm_hour = v[3];
tm.tm_min = v[4];
tm.tm_sec = v[5];
/* v[6] is the timezone offset, in 1/4-hour increments. */
offset = ((const signed char *)p)[6];
tm.tm_hour += offset / 4;
tm.tm_min += (offset % 4) * 15;
return (timegm(&tm));
}
static const char *
build_pathname(struct archive_string *as, struct dir_rec *dr)
{
if (dr->parent != NULL && dr->parent->name[0] != '\0') {
build_pathname(as, dr->parent);
archive_strcat(as, "/");
}
archive_strcat(as, dr->name);
return (as->s);
}