src/archive.cc

   1
   2 /**
   3  *
   4  * Tennix Archive File Format
   5  * Copyright (C) 2009-2010 Thomas Perl <thp@thpinfo.com>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * as published by the Free Software Foundation; either version 2
  10  * of the License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  20  * MA  02110-1301, USA.
  21  *
  22  **/
  23
  24 #include "tennix.h"
  25
  26 #include <iostream>
  27
  28 #include <libgen.h>
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <unistd.h>
  33 #include <errno.h>
  34 #include <sys/types.h>
  35 #include <sys/stat.h>
  36
  37 #include <arpa/inet.h>
  38
  39 #include "archive.h"
  40
  41 static void
  42 xormem(char* mem, uint32_t length, char key)
  43 {
  44    char *i = mem, *end = mem+length;
  45    for(; i != end; i++) {
  46        *i ^= key;
  47    }
  48 }
  49
  50 TennixArchive::TennixArchive()
  51     : fp(NULL)
  52     , header()
  53     , items(NULL)
  54     , blobs(NULL)
  55     , offset(0)
  56     , current_item(0)
  57 {
  58     strcpy(header.header, TENNIX_ARCHIVE_HEADER);
  59     header.items = 0;
  60 }
  61
  62 TennixArchive::TennixArchive(const char* filename, const char* fallback)
  63     : fp(NULL)
  64     , header()
  65     , items(NULL)
  66     , blobs(NULL)
  67     , offset(0)
  68     , current_item(0)
  69 {
  70     fp = fopen(filename, "rb");
  71     if (fp == NULL && fallback != NULL) {
  72         fp = fopen(fallback, "rb");
  73     }
  74
  75     if (fp == NULL) {
  76         fprintf(stderr, "Cannot open archive: %s\n", filename);
  77         exit(1);
  78     }
  79
  80     offset = sizeof(TennixArchiveHeader)*fread(&(header), sizeof(TennixArchiveHeader), 1, fp);
  81     tnx_assert(offset == sizeof(TennixArchiveHeader));
  82     tnx_assert(strncmp(header.header, TENNIX_ARCHIVE_HEADER, TENNIX_ARCHIVE_HEADER_LEN) == 0);
  83     tnx_assert(header.versionmajor == TENNIX_ARCHIVE_VERSIONMAJOR);
  84     tnx_assert(header.versionminor == TENNIX_ARCHIVE_VERSIONMINOR);
  85
  86     items = (TennixArchiveItem*)calloc(header.items, sizeof(TennixArchiveItem));
  87     tnx_assert(items != NULL);
  88     offset += sizeof(TennixArchiveItem)*fread(items, sizeof(TennixArchiveItem), header.items, fp);
  89     tnx_assert(offset == sizeof(TennixArchiveHeader) + header.items*sizeof(TennixArchiveItem));
  90
  91     xormem((char*)(items), header.items*sizeof(TennixArchiveItem), header.key);
  92
  93     for (int i=0; i<header.items; i++) {
  94         /* convert offset + length from network byte order */
  95         items[i].offset = ntohl(items[i].offset);
  96         items[i].length = ntohl(items[i].length);
  97     }
  98 }
  99
 100 std::ostream&
 101 operator<<(std::ostream& out, TennixArchiveHeader& header)
 102 {
 103     out << "Header: " << header.header << std::endl;
 104     out << "Version: " <<
 105         (int)header.versionmajor << '.' <<
 106         (int)header.versionminor << std::endl;
 107     out << "Master key: " << header.key << std::endl;
 108     out << "Items: " << header.items;
 109
 110     return out;
 111 }
 112
 113 std::ostream&
 114 operator<<(std::ostream& out, TennixArchiveItem& item)
 115 {
 116     out << "File: " << item.filename << std::endl;
 117     out << "Size: " << item.length << std::endl;
 118     out << "Offset: " << item.offset << std::endl;
 119     out << "Key: " << (int)item.key;
 120
 121     return out;
 122 }
 123
 124 int
 125 TennixArchive::setItemFilename(const char* filename)
 126 {
 127     int i;
 128
 129     for (i=0; i<header.items; i++) {
 130         if (strncmp(items[i].filename, filename, TENNIX_ARCHIVE_ITEM_MAXNAME) == 0) {
 131             current_item = i;
 132             return 1;
 133         }
 134     }
 135
 136     return 0;
 137 }
 138
 139 char*
 140 TennixArchive::getItemBytes()
 141 {
 142     size_t size = getItemSize();
 143     char* data = (char*)malloc(size+1);
 144     /* the last char is a null character, so this works for strings, too */
 145     data[size]='\0';
 146     fseek(fp, items[current_item].offset, SEEK_SET);
 147     tnx_assert(fread(data, size, 1, fp) == 1);
 148     xormem(data, size, items[current_item].key);
 149     return data;
 150 }
 151
 152 void
 153 TennixArchive::appendItem(char* filename, char* data, uint32_t length)
 154 {
 155     TennixArchiveItem* item;
 156
 157     header.items++;
 158     items = (TennixArchiveItem*)realloc(items, sizeof(TennixArchiveItem)*header.items);
 159     blobs = (char**)realloc(blobs, sizeof(char*)*header.items);
 160
 161     item = &(items[header.items-1]);
 162     blobs[header.items-1] = data;
 163     for (int i=0; i<TENNIX_ARCHIVE_ITEM_MAXNAME; i++) {
 164         item->filename[i] = data[(i*2)%length];
 165     }
 166     strcpy(item->filename, filename);
 167     item->length = length;
 168 }
 169
 170 void
 171 TennixArchive::buildFile(char* filename)
 172 {
 173     size_t offset = 0;
 174     size_t *memsize = NULL;
 175
 176     memsize = (size_t*)calloc(header.items, sizeof(size_t));
 177
 178     fp = fopen(filename, "wb");
 179     tnx_assert(fp != NULL);
 180
 181     offset += sizeof(TennixArchiveHeader) + header.items*sizeof(TennixArchiveItem);
 182
 183     header.versionmajor = TENNIX_ARCHIVE_VERSIONMAJOR;
 184     header.versionminor = TENNIX_ARCHIVE_VERSIONMINOR;
 185
 186     header.key = (0xaa + 0x77*header.items*3) % 0xff;
 187
 188     for (int i=0; i<header.items; i++) {
 189         items[i].offset = htonl(offset); /* network byte order */
 190         items[i].key = 0xaa ^ ((i<<2)%0x100);
 191         xormem(blobs[i], items[i].length, items[i].key);
 192         memsize[i] = items[i].length;
 193         offset += items[i].length;
 194         items[i].length = htonl(items[i].length); /* network byte order */
 195         xormem((char*)(items + i), sizeof(TennixArchiveItem), header.key);
 196     }
 197
 198     tnx_assert(fwrite(&(header), sizeof(TennixArchiveHeader), 1, fp) == 1);
 199     tnx_assert(fwrite(items, sizeof(TennixArchiveItem), header.items, fp) == header.items);
 200     for (int i=0; i<header.items; i++) {
 201         tnx_assert(fwrite(blobs[i], memsize[i], 1, fp) == 1);
 202         free(blobs[i]);
 203     }
 204
 205     free(memsize);
 206     free(blobs);
 207 }
 208
 209 std::ostream&
 210 operator<<(std::ostream& out, TennixArchive& archive)
 211 {
 212     out << "Tennix Archive" << std::endl;
 213     out << archive.header << std::endl;
 214
 215     for (int i=0; i<archive.header.items; i++) {
 216         out << "=======================" << std::endl;
 217         out << archive.items[i] << std::endl;
 218     }
 219     out << "=== END OF ARCHIVE ====" << std::endl;
 220
 221     return out;
 222 }
 223