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     , building(1)
  58 {
  59     strcpy(header.header, TENNIX_ARCHIVE_HEADER);
  60     header.items = 0;
  61 }
  62
  63 TennixArchive::TennixArchive(const char* filename, const char* fallback)
  64     : fp(NULL)
  65     , header()
  66     , items(NULL)
  67     , blobs(NULL)
  68     , offset(0)
  69     , current_item(0)
  70     , building(0)
  71 {
  72     fp = fopen(filename, "rb");
  73     if (fp == NULL && fallback != NULL) {
  74         fp = fopen(fallback, "rb");
  75     }
  76
  77     if (fp == NULL) {
  78         fprintf(stderr, "Cannot open archive: %s\n", filename);
  79         exit(1);
  80     }
  81
  82     offset = sizeof(TennixArchiveHeader)*fread(&(header), sizeof(TennixArchiveHeader), 1, fp);
  83     tnx_assert(offset == sizeof(TennixArchiveHeader));
  84     tnx_assert(strncmp(header.header, TENNIX_ARCHIVE_HEADER, TENNIX_ARCHIVE_HEADER_LEN) == 0);
  85     tnx_assert(header.versionmajor == TENNIX_ARCHIVE_VERSIONMAJOR);
  86     tnx_assert(header.versionminor == TENNIX_ARCHIVE_VERSIONMINOR);
  87
  88     items = (TennixArchiveItem*)calloc(header.items, sizeof(TennixArchiveItem));
  89     tnx_assert(items != NULL);
  90     offset += sizeof(TennixArchiveItem)*fread(items, sizeof(TennixArchiveItem), header.items, fp);
  91     tnx_assert(offset == sizeof(TennixArchiveHeader) + header.items*sizeof(TennixArchiveItem));
  92
  93     xormem((char*)(items), header.items*sizeof(TennixArchiveItem), header.key);
  94
  95     for (int i=0; i<header.items; i++) {
  96         /* convert offset + length from network byte order */
  97         items[i].offset = ntohl(items[i].offset);
  98         items[i].length = ntohl(items[i].length);
  99     }
 100 }
 101
 102 std::ostream&
 103 operator<<(std::ostream& out, TennixArchiveHeader& header)
 104 {
 105     out << "Header: " << header.header << std::endl;
 106     out << "Version: " <<
 107         (int)header.versionmajor << '.' <<
 108         (int)header.versionminor << std::endl;
 109     out << "Master key: " << header.key << std::endl;
 110     out << "Items: " << header.items;
 111
 112     return out;
 113 }
 114
 115 std::ostream&
 116 operator<<(std::ostream& out, TennixArchiveItem& item)
 117 {
 118     out << "File: " << item.filename << std::endl;
 119     out << "Size: " << item.length << std::endl;
 120     out << "Offset: " << item.offset << std::endl;
 121     out << "Key: " << (int)item.key;
 122
 123     return out;
 124 }
 125
 126 int
 127 TennixArchive::setItemFilename(const char* filename)
 128 {
 129     int i;
 130
 131     for (i=0; i<header.items; i++) {
 132         if (strncmp(items[i].filename, filename, TENNIX_ARCHIVE_ITEM_MAXNAME) == 0) {
 133             current_item = i;
 134             return 1;
 135         }
 136     }
 137
 138     return 0;
 139 }
 140
 141 char*
 142 TennixArchive::getItemBytes()
 143 {
 144     size_t size = getItemSize();
 145     char* data = (char*)malloc(size+1);
 146     /* the last char is a null character, so this works for strings, too */
 147     data[size]='\0';
 148     fseek(fp, items[current_item].offset, SEEK_SET);
 149     tnx_assert(fread(data, size, 1, fp) == 1);
 150     xormem(data, size, items[current_item].key);
 151     return data;
 152 }
 153
 154 void
 155 TennixArchive::appendItem(char* filename, char* data, uint32_t length)
 156 {
 157     TennixArchiveItem* item;
 158
 159     header.items++;
 160     items = (TennixArchiveItem*)realloc(items, sizeof(TennixArchiveItem)*header.items);
 161     blobs = (char**)realloc(blobs, sizeof(char*)*header.items);
 162
 163     item = &(items[header.items-1]);
 164     blobs[header.items-1] = data;
 165     for (int i=0; i<TENNIX_ARCHIVE_ITEM_MAXNAME; i++) {
 166         item->filename[i] = data[(i*2)%length];
 167     }
 168     strcpy(item->filename, filename);
 169     item->length = length;
 170 }
 171
 172 void
 173 TennixArchive::buildFile(char* filename)
 174 {
 175     size_t offset = 0;
 176     size_t *memsize = NULL;
 177
 178     memsize = (size_t*)calloc(header.items, sizeof(size_t));
 179
 180     fp = fopen(filename, "wb");
 181     tnx_assert(fp != NULL);
 182
 183     offset += sizeof(TennixArchiveHeader) + header.items*sizeof(TennixArchiveItem);
 184
 185     header.versionmajor = TENNIX_ARCHIVE_VERSIONMAJOR;
 186     header.versionminor = TENNIX_ARCHIVE_VERSIONMINOR;
 187
 188     header.key = (0xaa + 0x77*header.items*3) % 0xff;
 189
 190     for (int i=0; i<header.items; i++) {
 191         items[i].offset = htonl(offset); /* network byte order */
 192         items[i].key = 0xaa ^ ((i<<2)%0x100);
 193         xormem(blobs[i], items[i].length, items[i].key);
 194         memsize[i] = items[i].length;
 195         offset += items[i].length;
 196         items[i].length = htonl(items[i].length); /* network byte order */
 197         xormem((char*)(items + i), sizeof(TennixArchiveItem), header.key);
 198     }
 199
 200     tnx_assert(fwrite(&(header), sizeof(TennixArchiveHeader), 1, fp) == 1);
 201     tnx_assert(fwrite(items, sizeof(TennixArchiveItem), header.items, fp) == header.items);
 202     for (int i=0; i<header.items; i++) {
 203         tnx_assert(fwrite(blobs[i], memsize[i], 1, fp) == 1);
 204         free(blobs[i]);
 205     }
 206
 207     free(memsize);
 208     free(blobs);
 209 }
 210
 211 std::ostream&
 212 operator<<(std::ostream& out, TennixArchive& archive)
 213 {
 214     out << "Tennix Archive" << std::endl;
 215     out << archive.header << std::endl;
 216
 217     for (int i=0; i<archive.header.items; i++) {
 218         out << "=======================" << std::endl;
 219         out << archive.items[i] << std::endl;
 220     }
 221     out << "=== END OF ARCHIVE ====" << std::endl;
 222
 223     return out;
 224 }
 225