zip_crack.c

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdint.h>

#include "zip_crack.h"

static const uint32_t crc_32_tab[] =
{
    0x00000000UL, 0x77073096UL, 0xee0e612cUL, 0x990951baUL, 0x076dc419UL,
    0x706af48fUL, 0xe963a535UL, 0x9e6495a3UL, 0x0edb8832UL, 0x79dcb8a4UL,
    0xe0d5e91eUL, 0x97d2d988UL, 0x09b64c2bUL, 0x7eb17cbdUL, 0xe7b82d07UL,
    0x90bf1d91UL, 0x1db71064UL, 0x6ab020f2UL, 0xf3b97148UL, 0x84be41deUL,
    0x1adad47dUL, 0x6ddde4ebUL, 0xf4d4b551UL, 0x83d385c7UL, 0x136c9856UL,
    0x646ba8c0UL, 0xfd62f97aUL, 0x8a65c9ecUL, 0x14015c4fUL, 0x63066cd9UL,
    0xfa0f3d63UL, 0x8d080df5UL, 0x3b6e20c8UL, 0x4c69105eUL, 0xd56041e4UL,
    0xa2677172UL, 0x3c03e4d1UL, 0x4b04d447UL, 0xd20d85fdUL, 0xa50ab56bUL,
    0x35b5a8faUL, 0x42b2986cUL, 0xdbbbc9d6UL, 0xacbcf940UL, 0x32d86ce3UL,
    0x45df5c75UL, 0xdcd60dcfUL, 0xabd13d59UL, 0x26d930acUL, 0x51de003aUL,
    0xc8d75180UL, 0xbfd06116UL, 0x21b4f4b5UL, 0x56b3c423UL, 0xcfba9599UL,
    0xb8bda50fUL, 0x2802b89eUL, 0x5f058808UL, 0xc60cd9b2UL, 0xb10be924UL,
    0x2f6f7c87UL, 0x58684c11UL, 0xc1611dabUL, 0xb6662d3dUL, 0x76dc4190UL,
    0x01db7106UL, 0x98d220bcUL, 0xefd5102aUL, 0x71b18589UL, 0x06b6b51fUL,
    0x9fbfe4a5UL, 0xe8b8d433UL, 0x7807c9a2UL, 0x0f00f934UL, 0x9609a88eUL,
    0xe10e9818UL, 0x7f6a0dbbUL, 0x086d3d2dUL, 0x91646c97UL, 0xe6635c01UL,
    0x6b6b51f4UL, 0x1c6c6162UL, 0x856530d8UL, 0xf262004eUL, 0x6c0695edUL,
    0x1b01a57bUL, 0x8208f4c1UL, 0xf50fc457UL, 0x65b0d9c6UL, 0x12b7e950UL,
    0x8bbeb8eaUL, 0xfcb9887cUL, 0x62dd1ddfUL, 0x15da2d49UL, 0x8cd37cf3UL,
    0xfbd44c65UL, 0x4db26158UL, 0x3ab551ceUL, 0xa3bc0074UL, 0xd4bb30e2UL,
    0x4adfa541UL, 0x3dd895d7UL, 0xa4d1c46dUL, 0xd3d6f4fbUL, 0x4369e96aUL,
    0x346ed9fcUL, 0xad678846UL, 0xda60b8d0UL, 0x44042d73UL, 0x33031de5UL,
    0xaa0a4c5fUL, 0xdd0d7cc9UL, 0x5005713cUL, 0x270241aaUL, 0xbe0b1010UL,
    0xc90c2086UL, 0x5768b525UL, 0x206f85b3UL, 0xb966d409UL, 0xce61e49fUL,
    0x5edef90eUL, 0x29d9c998UL, 0xb0d09822UL, 0xc7d7a8b4UL, 0x59b33d17UL,
    0x2eb40d81UL, 0xb7bd5c3bUL, 0xc0ba6cadUL, 0xedb88320UL, 0x9abfb3b6UL,
    0x03b6e20cUL, 0x74b1d29aUL, 0xead54739UL, 0x9dd277afUL, 0x04db2615UL,
    0x73dc1683UL, 0xe3630b12UL, 0x94643b84UL, 0x0d6d6a3eUL, 0x7a6a5aa8UL,
    0xe40ecf0bUL, 0x9309ff9dUL, 0x0a00ae27UL, 0x7d079eb1UL, 0xf00f9344UL,
    0x8708a3d2UL, 0x1e01f268UL, 0x6906c2feUL, 0xf762575dUL, 0x806567cbUL,
    0x196c3671UL, 0x6e6b06e7UL, 0xfed41b76UL, 0x89d32be0UL, 0x10da7a5aUL,
    0x67dd4accUL, 0xf9b9df6fUL, 0x8ebeeff9UL, 0x17b7be43UL, 0x60b08ed5UL,
    0xd6d6a3e8UL, 0xa1d1937eUL, 0x38d8c2c4UL, 0x4fdff252UL, 0xd1bb67f1UL,
    0xa6bc5767UL, 0x3fb506ddUL, 0x48b2364bUL, 0xd80d2bdaUL, 0xaf0a1b4cUL,
    0x36034af6UL, 0x41047a60UL, 0xdf60efc3UL, 0xa867df55UL, 0x316e8eefUL,
    0x4669be79UL, 0xcb61b38cUL, 0xbc66831aUL, 0x256fd2a0UL, 0x5268e236UL,
    0xcc0c7795UL, 0xbb0b4703UL, 0x220216b9UL, 0x5505262fUL, 0xc5ba3bbeUL,
    0xb2bd0b28UL, 0x2bb45a92UL, 0x5cb36a04UL, 0xc2d7ffa7UL, 0xb5d0cf31UL,
    0x2cd99e8bUL, 0x5bdeae1dUL, 0x9b64c2b0UL, 0xec63f226UL, 0x756aa39cUL,
    0x026d930aUL, 0x9c0906a9UL, 0xeb0e363fUL, 0x72076785UL, 0x05005713UL,
    0x95bf4a82UL, 0xe2b87a14UL, 0x7bb12baeUL, 0x0cb61b38UL, 0x92d28e9bUL,
    0xe5d5be0dUL, 0x7cdcefb7UL, 0x0bdbdf21UL, 0x86d3d2d4UL, 0xf1d4e242UL,
    0x68ddb3f8UL, 0x1fda836eUL, 0x81be16cdUL, 0xf6b9265bUL, 0x6fb077e1UL,
    0x18b74777UL, 0x88085ae6UL, 0xff0f6a70UL, 0x66063bcaUL, 0x11010b5cUL,
    0x8f659effUL, 0xf862ae69UL, 0x616bffd3UL, 0x166ccf45UL, 0xa00ae278UL,
    0xd70dd2eeUL, 0x4e048354UL, 0x3903b3c2UL, 0xa7672661UL, 0xd06016f7UL,
    0x4969474dUL, 0x3e6e77dbUL, 0xaed16a4aUL, 0xd9d65adcUL, 0x40df0b66UL,
    0x37d83bf0UL, 0xa9bcae53UL, 0xdebb9ec5UL, 0x47b2cf7fUL, 0x30b5ffe9UL,
    0xbdbdf21cUL, 0xcabac28aUL, 0x53b39330UL, 0x24b4a3a6UL, 0xbad03605UL,
    0xcdd70693UL, 0x54de5729UL, 0x23d967bfUL, 0xb3667a2eUL, 0xc4614ab8UL,
    0x5d681b02UL, 0x2a6f2b94UL, 0xb40bbe37UL, 0xc30c8ea1UL, 0x5a05df1bUL,
    0x2d02ef8dL
};

#define crc32(crc,byte) (crc_32_tab[(uint8_t)(crc) ^ (uint8_t)(byte)] ^ ((crc) >> 8))

static uint32_t
_fgetu32 (FILE * f)
{
  return (fgetc(f) << 0) |
    (fgetc(f) << 8) |
    (fgetc(f) << 16) |
    (fgetc(f) << 24);
}

static uint32_t
_fgetu16 (FILE * f)
{
  return (fgetc(f) << 0) |
    (fgetc(f) << 8);
}

/* Quick and Dirty */
static int
_zip_test_unzip(const char * file, const char * pwd)
{
    char buff[1024];

    sprintf (buff, "unzip -qqtP \"%s\" %s > /dev/null 2>&1", pwd, file);
    return system (buff) == EXIT_SUCCESS ? 0 : -1;
}

struct zip_archive * 
zip_load_archive (const char * file)
{
    FILE *f;
    uint32_t id;
    uint16_t flags;
    uint16_t lastmodtime;
    uint32_t crc32;
    uint32_t compr_size;
    uint16_t name_len;
    uint16_t extra_field_len;
    char zip_path[1024];
    struct zip_archive * archive;
    
    archive = malloc(sizeof(*archive));
    if (archive == NULL)
        return NULL;
    
    f = fopen (file, "rb");
    if (f == NULL) {
        goto fail2;
    }

    memcpy((void *) archive->file_path, file, sizeof(archive->file_path));

    while (!feof(f)) {
        id = _fgetu32(f);
        if (id == 0x04034b50UL) {
            flags = _fgetu16(f);
            lastmodtime = _fgetu16(f);
            crc32 = _fgetu32(f);
            compr_size = _fgetu32(f);
            name_len = _fgetu16(f);
            extra_field_len = _fgetu16(f);

            if (name_len < 1024) {
                fread (zip_path, name_len, 1, f);
                zip_path[name_len] = 0;
            } else {
                goto fail;
            }

            fseek (f, extra_field_len, SEEK_CUR);

            if (flags & 1) {
                if (compr_size >= 12) {
                    fread (archive->buffer, FILE_SIZE, 1, f);

                    if (flags & 8) {
                        archive->buffer[FILE_SIZE] = lastmodtime >> 8;
                        archive->buffer[FILE_SIZE + 1] = lastmodtime;
                    } else {
                        archive->buffer[FILE_SIZE] = crc32 >> 24;
                        archive->buffer[FILE_SIZE + 1] = crc32 >> 16;
                    }

                    compr_size -= 12;
                } else {
                    goto fail;
                }
                /* found one encrypted file */
                goto out;
            }

            fseek (f, compr_size, SEEK_CUR);
        } else if (id == 0x08074b50UL) {
            fseek (f, 12, SEEK_CUR);
        } else if (id == 0x30304b50UL) {
          /* ignore */
        } else if (id == 0x02014b50UL || id == 0x06054b50UL) {
            goto out;
        } else {
            goto fail;
        }
    }


fail:
    fclose(f);
fail2:
    zip_close_archive(archive);
    return NULL;

out:
    fclose(f);
    return archive;
}

void 
zip_close_archive(struct zip_archive * archive)
{
    free(archive);
}


int
zip_test_password (struct zip_archive * archive, const char * pwd) 
{
    uint32_t key0, key1, key2;
    uint32_t kez0, kez1, kez2;
    uint8_t * p;
    uint8_t * e;
    uint8_t * b;
    uint16_t t;
    uint8_t target, pre_target;
    
    key0 = 0x12345678UL;
    key1 = 0x23456789UL;
    key2 = 0x34567890UL;
    p = (uint8_t *) pwd;
    
    do {
        key0 = crc32 (key0, *p++);
        key1 = (key1 + (uint8_t)key0) * 134775813 + 1;
        key2 = crc32 (key2, key1 >> 24);
    } while (*p);
    
    b = (uint8_t *) archive->buffer;
    e = b + FILE_SIZE - 1;
    kez0 = key0, kez1 = key1, kez2 = key2;
    
    do {
        t = kez2 | 2;
        pre_target = *b++ ^ (uint8_t)(((uint16_t) (t * (t^1)) >> 8));
        kez0 = crc32 (kez0, pre_target);
        kez1 = (kez1 + (uint8_t)kez0) * 134775813 + 1;
        kez2 = crc32 (kez2, kez1 >> 24);
    } while (b < e);
    
    t = kez2 | 2;
    target = *b++ ^ (uint8_t)(((uint16_t) (t * (t^1)) >> 8));
    
    if (target != *b++)
        return -1;
    
    /* possible password found */
    return _zip_test_unzip(archive->file_path, pwd);
}