emo/busybox
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Modified so that it "works" for archs other than i386... arm in particular.

Browse Source 
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 2002-09-17 21:02:16 +00:00
parent 60943c5d5c
commit 6c32a8add4
1 changed files with 108 additions and 47 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

155
archival/libunarchive/get_header_zip.c
View File

@ -19,92 +19,153 @@
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/ */
#include <stddef.h>
#include <stdio.h> #include <stdio.h>
#include <stdlib.h> #include <stdlib.h>
#include <string.h> #include <string.h>
#include "unarchive.h" #include "unarchive.h"
#include "libbb.h" #include "libbb.h"
#define ZIP_FILEHEADER_MAGIC 0x04034b50 #define ZIP_FILEHEADER_MAGIC 0x04034b50
#define ZIP_CDS_MAGIC 0x02014b50 #define ZIP_CDS_MAGIC 0x02014b50
#define ZIP_CDS_END_MAGIC 0x06054b50 #define ZIP_CDS_END_MAGIC 0x06054b50
#define ZIP_DD_MAGIC 0x8074b50 #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) file_header_t *get_header_zip(FILE *zip_stream)
{ {
struct { int zip_header[10];
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;
file_header_t *zip_entry = NULL; file_header_t *zip_entry = NULL;
int magic; int magic, tmpmagic;
static int dd_ahead = 0; // If this is true, the we didn't know how long the last extraced file was /* 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); magic = le_read_int(zip_stream, 4);
archive_offset += 4;
if (feof(zip_stream)) return(NULL); checkmagic:
checkmagic:
switch (magic) { switch (magic) {
case ZIP_FILEHEADER_MAGIC: case ZIP_FILEHEADER_MAGIC:
zip_entry = xcalloc(1, sizeof(file_header_t)); zip_entry = xcalloc(1, sizeof(file_header_t));
fread (&zip_header, sizeof(zip_header), 1, zip_stream);
archive_offset += sizeof(zip_header); read_header(zip_stream, 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)); if (zip_header[zh_method] == 8) {
fread (zip_entry->name, sizeof(char), zip_header.filename_len, zip_stream); zip_entry->extract_func = &inflate;
archive_offset += zip_header.filename_len; } else if (zip_header[zh_method] != 0) {
seek_sub_file(zip_stream, zip_header.extra_len); error_msg_and_die("Unsupported compression method %d\n",
zip_entry->size = zip_header.cmpsize; zip_header[zh_method]);
if (zip_header.method == 8) zip_entry->extract_func = &inflate; }
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; 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_IFREG;
zip_entry->mode |= S_IFDIR; 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[zh_flags] & 0x8) {
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 /* crc32, and sizes are in the data description _after_ the file */
if (zip_header.ucmpsize != 0) dd_ahead = 2; // Humm... we would otherwise skip this twice - not good! 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; break;
case ZIP_CDS_MAGIC: /* FALLTHRU */ case ZIP_CDS_MAGIC: /* FALLTHRU */
case ZIP_CDS_END_MAGIC: case ZIP_CDS_END_MAGIC:
return(NULL); return(NULL);
break; break;
case ZIP_DD_MAGIC: { case ZIP_DD_MAGIC: {
int cmpsize; int cmpsize;
seek_sub_file(zip_stream, 4); // Skip crc32 seek_sub_file(zip_stream, 4); // Skip crc32
fread(&cmpsize, 4, 1, zip_stream); cmpsize = le_read_int(zip_stream, 4);
archive_offset += 4;
if (dd_ahead == 1) archive_offset += cmpsize; if (dd_ahead == 1) archive_offset += cmpsize;
seek_sub_file(zip_stream, 4); // Skip uncompressed size seek_sub_file(zip_stream, 4); // Skip uncompressed size
dd_ahead = 0; dd_ahead = 0;
return (get_header_zip(zip_stream)); return (get_header_zip(zip_stream));
break; } break; }
default: default:
if (!dd_ahead) error_msg("Invalid magic (%#x): Trying to skip junk", magic); if (!dd_ahead) error_msg("Invalid magic (%#x): Trying to skip junk", magic);
dd_ahead = 0; dd_ahead = 0;
while (!feof(zip_stream)) { while ((tmpmagic = fgetc(zip_stream)) != EOF) {
int tmpmagic;
tmpmagic = fgetc(zip_stream);
archive_offset++; archive_offset++;
magic = ((magic >> 8) & 0x00ffffff) | ((tmpmagic << 24) & 0xff000000); 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"); error_msg_and_die(fail_msg);
return(NULL);
} }
//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); return(zip_entry);
} }