cvs.zerfleddert.de Git - rsbs2/blob - extract.c

   1 #include <sys/stat.h>
   2 #include <sys/types.h>
   3 #include <limits.h>
   4 #include <fcntl.h>
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include <strings.h>
   8 #include <string.h>
   9 #include <unistd.h>
  10 #include <errno.h>
  11 #include <libgen.h>
  12 #include "rsb-lz.h"
  13 #include "extract.h"
  14
  15 struct file_entry* get_next_file(unsigned char *fw, int len)
  16 {
  17         static unsigned char *pos;
  18         static unsigned char *end;
  19         static struct file_entry fent;
  20         int name_length;
  21
  22         if (fw != NULL && len != 0) {
  23                 pos = fw + 0x28;
  24
  25                 printf("Start of filesystem: 0x%08x\n", *((unsigned int*)pos));
  26                 pos = fw + *((unsigned int*)pos);
  27                 end = fw + len;
  28         }
  29
  30         fent.unknown = *pos;
  31         pos++;
  32
  33         name_length = *((unsigned int*)pos);
  34         pos += 4;
  35
  36         fent.length = *((unsigned int*)pos);
  37         pos += 4;
  38
  39         if ((fent.length > (end - pos)) ||
  40             (name_length > (end - pos))) {
  41                 printf("EOF reached\n");
  42                 return NULL;
  43         }
  44
  45         fent.name = (char*)pos;
  46         pos += name_length;
  47
  48         fent.start = pos;
  49         pos += fent.length;
  50
  51         return &fent;
  52 }
  53
  54 void extract_files(unsigned char *fw, int len)
  55 {
  56         struct file_entry *fent;
  57
  58         fent = get_next_file(fw, len);
  59
  60         while (fent) {
  61                 printf("%s: unknown: 0x%02x, length: %d",
  62                         fent->name, fent->unknown, fent->length);
  63
  64                 if (fent->length > 0) {
  65                         write_file(fent->name, fent->start, fent->length);
  66                         if (*((unsigned int*)fent->start) == LZ_MAGIC) {
  67                                 char *lzname;
  68
  69                                 if ((lzname = strdup(fent->name)) == NULL) {
  70                                         perror("strdup");
  71                                         exit(1);
  72                                 }
  73
  74                                 if (!strcmp(lzname + strlen(lzname) - 4 , ".lz")) {
  75                                         fprintf(stderr, "Ugh, can't derive filename...\n");
  76                                         exit(1);
  77                                 }
  78                                 lzname[strlen(lzname) - 3] = 0x00;
  79
  80                                 printf("%s: packed file found", lzname);
  81
  82                                 extract_lz_file(fent->start, (unsigned char*)lzname);
  83                                 free(lzname);
  84                         } else if (!strcmp(fent->name, "firmware")) {
  85                                 unsigned char *lzpos;
  86                                 char lzname[128];
  87
  88                                 bzero(lzname, sizeof(lzname));
  89                                 strcpy(lzname, "firmware.");
  90
  91                                 lzpos = fent->start + *((unsigned int*)(fent->start + 0x20));
  92                                 memcpy(lzname + strlen(lzname), lzpos - 4, 4);
  93                                 lzpos += 4;
  94                                 if (*((unsigned int*)(lzpos)) == LZ_MAGIC) {
  95                                         printf("%s: compressed firmware part found", lzname);
  96                                         extract_lz_file(lzpos, (unsigned char*)lzname);
  97                                 }
  98                         }
  99                 }
 100                 fent = get_next_file(NULL, 0);
 101         }
 102 }
 103
 104 void mkdir_p(char *dir)
 105 {
 106         char *copy, *parent;
 107
 108         if ((dir == NULL) || (!strcmp(dir, ".")))
 109                 return;
 110
 111         if ((copy = strdup(dir)) == NULL) {
 112                 perror("strdup");
 113                 exit(1);
 114         }
 115         parent = dirname(copy);
 116         mkdir_p(parent);
 117
 118         errno = 0;
 119         if (mkdir(dir, 0755) == -1) {
 120                 if (errno != EEXIST) {
 121                         fprintf(stderr, "%s: ", dir);
 122                         perror("mkdir");
 123                         exit(1);
 124                 }
 125         }
 126         free(copy);
 127 }
 128
 129 void write_file(char *fname, unsigned char *buf, int len)
 130 {
 131         char filename[PATH_MAX];
 132         char *filename_c, *dirn;
 133         int fd;
 134         int remaining;
 135         int ret;
 136
 137         strcpy(filename, "extracted/");
 138         strcat(filename, fname);
 139
 140         if ((filename_c = strdup(filename)) == NULL) {
 141                 perror("strdup");
 142                 exit(1);
 143         }
 144         dirn = dirname(filename_c);
 145         mkdir_p(dirn);
 146         free(filename_c);
 147
 148         if ((fd = open(filename, O_WRONLY|O_CREAT, 0644)) == -1) {
 149                 fprintf(stderr, "%s: ", filename);
 150                 perror("open");
 151                 exit(1);
 152         }
 153
 154         remaining = len;
 155
 156         while(remaining) {
 157                 ret = write(fd, buf + (len - remaining), remaining);
 158                 if (ret < 0) {
 159                         perror("write");
 160                         exit(1);
 161                 }
 162                 remaining -= ret;
 163         }
 164
 165         printf(", %s written.\n", filename);
 166
 167         close(fd);
 168 }