mirror of
https://github.com/sheumann/hush.git
synced 2024-07-04 21:29:34 +00:00
Modified so that it "works" for archs other than i386... arm in particular.
Also tried to clean up the logic a little, and ensure that read errors or invalid archives resulted in error returns. This could use a lot more work... Volunteers?
This commit is contained in:
Manuel Novoa III
parent
60943c5d5c
commit
6c32a8add4
@ -19,92 +19,153 @@
|
||||
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
||||
*/
|
||||
|
||||
#include <stddef.h>
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
#include <string.h>
|
||||
#include "unarchive.h"
|
||||
#include "libbb.h"
|
||||
|
||||
#define ZIP_FILEHEADER_MAGIC 0x04034b50
|
||||
#define ZIP_CDS_MAGIC 0x02014b50
|
||||
#define ZIP_CDS_END_MAGIC 0x06054b50
|
||||
#define ZIP_DD_MAGIC 0x8074b50
|
||||
#define ZIP_FILEHEADER_MAGIC 0x04034b50
|
||||
#define ZIP_CDS_MAGIC 0x02014b50
|
||||
#define ZIP_CDS_END_MAGIC 0x06054b50
|
||||
#define ZIP_DD_MAGIC 0x08074b50
|
||||
|
||||
|
||||
enum {
|
||||
zh_version,
|
||||
zh_flags,
|
||||
zh_method,
|
||||
zh_modtime,
|
||||
zh_moddate,
|
||||
zh_crc32,
|
||||
zh_cmpsize,
|
||||
zh_ucmpsize,
|
||||
zh_filename_len,
|
||||
zh_extra_len
|
||||
};
|
||||
|
||||
static const char fail_msg[] = "Invalid file or read error";
|
||||
|
||||
static int le_read_int(FILE *fp, int n)
|
||||
{
|
||||
int r = 0;
|
||||
int s = 1;
|
||||
int c;
|
||||
|
||||
archive_offset += n;
|
||||
|
||||
do {
|
||||
if ((c = fgetc(fp)) == EOF) {
|
||||
error_msg_and_die(fail_msg);
|
||||
}
|
||||
r += s * c;
|
||||
s <<= 8;
|
||||
} while (--n);
|
||||
|
||||
return r;
|
||||
}
|
||||
|
||||
static void read_header(FILE *fp, int *zh)
|
||||
{
|
||||
static const char s[] = { 2, 2, 2, 2, 2, 4, 4, 4, 2, 2, 0 };
|
||||
int i = 0;
|
||||
|
||||
do {
|
||||
zh[i] = le_read_int(fp, s[i]);
|
||||
} while (s[++i]);
|
||||
}
|
||||
|
||||
file_header_t *get_header_zip(FILE *zip_stream)
|
||||
{
|
||||
struct {
|
||||
short version __attribute__ ((packed));
|
||||
short flags __attribute__ ((packed));
|
||||
short method __attribute__ ((packed));
|
||||
short modtime __attribute__ ((packed));
|
||||
short moddate __attribute__ ((packed));
|
||||
int crc32 __attribute__ ((packed));
|
||||
int cmpsize __attribute__ ((packed));
|
||||
int ucmpsize __attribute__ ((packed));
|
||||
short filename_len __attribute__ ((packed));
|
||||
short extra_len __attribute__ ((packed));
|
||||
} zip_header;
|
||||
int zip_header[10];
|
||||
file_header_t *zip_entry = NULL;
|
||||
int magic;
|
||||
static int dd_ahead = 0; // If this is true, the we didn't know how long the last extraced file was
|
||||
int magic, tmpmagic;
|
||||
/* If dd_ahead is true, we didn't know the last extracted file's length. */
|
||||
static int dd_ahead = 0;
|
||||
|
||||
fread (&magic, 4, 1, zip_stream);
|
||||
archive_offset += 4;
|
||||
magic = le_read_int(zip_stream, 4);
|
||||
|
||||
if (feof(zip_stream)) return(NULL);
|
||||
checkmagic:
|
||||
checkmagic:
|
||||
switch (magic) {
|
||||
case ZIP_FILEHEADER_MAGIC:
|
||||
zip_entry = xcalloc(1, sizeof(file_header_t));
|
||||
fread (&zip_header, sizeof(zip_header), 1, zip_stream);
|
||||
archive_offset += sizeof(zip_header);
|
||||
if (!(zip_header.method == 8 || zip_header.method == 0)) { printf("Unsupported compression method %d\n", zip_header.method); return(NULL); }
|
||||
zip_entry->name = calloc(zip_header.filename_len + 1, sizeof(char));
|
||||
fread (zip_entry->name, sizeof(char), zip_header.filename_len, zip_stream);
|
||||
archive_offset += zip_header.filename_len;
|
||||
seek_sub_file(zip_stream, zip_header.extra_len);
|
||||
zip_entry->size = zip_header.cmpsize;
|
||||
if (zip_header.method == 8) zip_entry->extract_func = &inflate;
|
||||
|
||||
read_header(zip_stream, zip_header);
|
||||
|
||||
if (zip_header[zh_method] == 8) {
|
||||
zip_entry->extract_func = &inflate;
|
||||
} else if (zip_header[zh_method] != 0) {
|
||||
error_msg_and_die("Unsupported compression method %d\n",
|
||||
zip_header[zh_method]);
|
||||
}
|
||||
|
||||
zip_entry->name = xmalloc(zip_header[zh_filename_len] + 1);
|
||||
if (!fread(zip_entry->name, zip_header[zh_filename_len], 1, zip_stream)) {
|
||||
error_msg_and_die(fail_msg);
|
||||
}
|
||||
archive_offset += zip_header[zh_filename_len];
|
||||
|
||||
seek_sub_file(zip_stream, zip_header[zh_extra_len]);
|
||||
|
||||
zip_entry->size = zip_header[zh_cmpsize];
|
||||
|
||||
zip_entry->mode = S_IFREG | 0777;
|
||||
// Time/Date?
|
||||
if (*(zip_entry->name + strlen(zip_entry->name) - 1) == '/') { // Files that end in a / are directories
|
||||
|
||||
/* Time/Date? */
|
||||
|
||||
zip_entry->name[zip_header[zh_filename_len]] = 0;
|
||||
if (*(zip_entry->name + zip_header[zh_filename_len] - 1) == '/') {
|
||||
/* Files that end in a / are directories */
|
||||
/* Remove trailing / so unarchive doesn't get confused */
|
||||
*(zip_entry->name + zip_header[zh_filename_len] - 1) = '\0';
|
||||
zip_entry->mode ^= S_IFREG;
|
||||
zip_entry->mode |= S_IFDIR;
|
||||
*(zip_entry->name + strlen(zip_entry->name) - 1) = '\0'; // Remove trailing / so unarchive doesn't get confused
|
||||
}
|
||||
//printf("cmpsize: %d, ucmpsize: %d, method: %d\n", zip_header.cmpsize, zip_header.ucmpsize, zip_header.method);
|
||||
if (zip_header.flags & 0x8) { // crc32, and sizes are in the data description _after_ the file
|
||||
if (zip_header.cmpsize == 0) dd_ahead = 1; // As we don't know how long this file it is difficult to skip! but it is compressed, so normally its ok
|
||||
if (zip_header.ucmpsize != 0) dd_ahead = 2; // Humm... we would otherwise skip this twice - not good!
|
||||
|
||||
if (zip_header[zh_flags] & 0x8) {
|
||||
/* crc32, and sizes are in the data description _after_ the file */
|
||||
if (zip_header[zh_cmpsize] == 0) {
|
||||
/* As we don't know how long this file it is difficult to skip!
|
||||
* but it is compressed, so normally its ok */
|
||||
dd_ahead = 1;
|
||||
}
|
||||
if (zip_header[zh_ucmpsize] != 0) {
|
||||
/* Humm... we would otherwise skip this twice - not good! */
|
||||
dd_ahead = 2;
|
||||
}
|
||||
}
|
||||
break;
|
||||
|
||||
case ZIP_CDS_MAGIC: /* FALLTHRU */
|
||||
case ZIP_CDS_END_MAGIC:
|
||||
return(NULL);
|
||||
break;
|
||||
|
||||
case ZIP_DD_MAGIC: {
|
||||
int cmpsize;
|
||||
seek_sub_file(zip_stream, 4); // Skip crc32
|
||||
fread(&cmpsize, 4, 1, zip_stream);
|
||||
archive_offset += 4;
|
||||
cmpsize = le_read_int(zip_stream, 4);
|
||||
if (dd_ahead == 1) archive_offset += cmpsize;
|
||||
seek_sub_file(zip_stream, 4); // Skip uncompressed size
|
||||
dd_ahead = 0;
|
||||
return (get_header_zip(zip_stream));
|
||||
break; }
|
||||
|
||||
default:
|
||||
if (!dd_ahead) error_msg("Invalid magic (%#x): Trying to skip junk", magic);
|
||||
dd_ahead = 0;
|
||||
while (!feof(zip_stream)) {
|
||||
int tmpmagic;
|
||||
tmpmagic = fgetc(zip_stream);
|
||||
while ((tmpmagic = fgetc(zip_stream)) != EOF) {
|
||||
archive_offset++;
|
||||
magic = ((magic >> 8) & 0x00ffffff) | ((tmpmagic << 24) & 0xff000000);
|
||||
if (magic == ZIP_FILEHEADER_MAGIC || magic == ZIP_CDS_MAGIC || magic == ZIP_CDS_END_MAGIC) goto checkmagic;
|
||||
if (magic == ZIP_FILEHEADER_MAGIC
|
||||
|| magic == ZIP_CDS_MAGIC
|
||||
|| magic == ZIP_CDS_END_MAGIC) {
|
||||
goto checkmagic;
|
||||
}
|
||||
}
|
||||
error_msg("End of archive reached: Bad archive");
|
||||
return(NULL);
|
||||
error_msg_and_die(fail_msg);
|
||||
}
|
||||
//if (archive_offset != ftell(zip_stream)) printf("Archive offset out of sync (%d,%d)\n", (int) archive_offset, (int) ftell(zip_stream));
|
||||
|
||||
return(zip_entry);
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user