tools/firmware-utils/src/mksercommfw.c

   1 #include <stdio.h>
   2 #include <string.h>
   3 #include <stdlib.h>
   4
   5 /* #define DEBUG 1 */
   6
   7 /*
   8  * Fw Header Layout for Netgear / Sercomm devices
   9  * */
  10 static const char *magic = "sErCoMm"; /* 7 */
  11 /* 7-11: version control/download control ? */
  12 unsigned char version[4] = {0x00, 0x01, 0x00, 0x00};
  13 char *hwID = ""; /* 11-43 , ASCII/HEX */
  14 char *hwVer = ""; /* 44-57 , ASCII/HEX */
  15 char *swVer = ""; /* 58-62 , ASCII/HEX */
  16 /* magic again. */
  17
  18 #define HEADER_SIZE 71
  19
  20 /* null bytes until 511 */
  21 u_int32_t checksum = 0xFF; /* checksum */
  22 /* 512 onwards -> ZIP containing rootfs with the same Header */
  23
  24
  25 /* appended on rootfs for the Header. */
  26 const int footer_size = 128;
  27
  28 struct file_info {
  29         char            *file_name;     /* name of the file */
  30         char            *file_data;     /* data of the file in memory */
  31         u_int32_t        file_size;     /* length of the file */
  32 };
  33
  34 u_int8_t getCheckSum(char *data, int len)
  35 {
  36
  37         int32_t previous = 0;
  38         u_int32_t new = 0;
  39
  40         for (u_int32_t i = 0; i < len; i++) {
  41                 new = (data[i] + previous) % 256;
  42                 previous = new | previous & -256;
  43         }
  44         return (u_int8_t) new;
  45 }
  46
  47 void *bufferFile(struct file_info *finfo, int dontload)
  48 {
  49         int fs = 0;
  50         FILE *f = NULL;
  51
  52 #ifdef DEBUG
  53         printf("Opening file: %s\n", finfo->file_name);
  54 #endif
  55         f = fopen(finfo->file_name, "rb");
  56         if (f == NULL) {
  57                 perror("Error");
  58                 exit(1);
  59         }
  60
  61         fseek(f, 0L, SEEK_END);
  62         fs = ftell(f);
  63         rewind(f);
  64
  65 #ifdef DEBUG
  66         printf("Filesize: %i .\n", fs);
  67 #endif
  68
  69         finfo->file_size = fs;
  70
  71         if (dontload) {
  72                 return 0;
  73         }
  74
  75         char *data = malloc(fs);
  76         finfo->file_data = data;
  77
  78         int read = fread(data, fs, 1, f);
  79
  80         if (read != 1) {
  81                 printf("Error reading file %s.", finfo->file_name);
  82                 exit(1);
  83         }
  84
  85 #ifdef DEBUG
  86         printf("File: read successfully %i bytes.\n", read*fs);
  87 #endif
  88         fclose(f);
  89 }
  90
  91 void *writeFile(struct file_info *finfo)
  92 {
  93
  94 #ifdef DEBUG
  95         printf("Writing file: %s.\n", finfo->file_name);
  96 #endif
  97
  98         FILE *fout = fopen(finfo->file_name, "w");
  99
 100         if (!fwrite(finfo->file_data, finfo->file_size, 1, fout)) {
 101                 printf("Wanted to write, but something went wrong.\n");
 102                 fclose(fout);
 103                 exit(1);
 104         }
 105         fclose(fout);
 106 }
 107
 108 void *rmFile(struct file_info *finfo)
 109 {
 110         remove(finfo->file_name);
 111         free(finfo->file_data);
 112         finfo->file_size = 0;
 113 }
 114
 115 void *usage(char *argv[])
 116 {
 117         printf("Usage: %s <sysupgradefile> <kernel_offset> <HWID> <HWVER> <SWID>\n"
 118                 "All are positional arguments ...       \n"
 119                 "       sysupgradefile:         File with the kernel uimage at 0\n"
 120                 "       kernel_offset:          Offset in Hex where the kernel is located\n"
 121                 "       HWID:                   Hardware ID, ASCII\n"
 122                 "       HWVER:                  Hardware Version, ASCII\n"
 123                 "       SWID:                   Software Version, Hex\n"
 124                 "       \n"
 125                 "       ", argv[0]);
 126 }
 127
 128 int main(int argc, char *argv[])
 129 {
 130         printf("Building fw image for sercomm devices.\n");
 131
 132         if (argc == 2) {
 133                 struct file_info myfile = {argv[1], 0, 0};
 134                 bufferFile(&myfile, 0);
 135                 char chksum = getCheckSum(myfile.file_data, myfile.file_size);
 136                 printf("Checksum for File: %X.\n", chksum);
 137                 return;
 138         }
 139
 140         if (argc != 6) {
 141                 usage(argv);
 142                 return 1;
 143         }
 144
 145         /* Args */
 146
 147         struct file_info sysupgrade = {argv[1], 0, 0};
 148         bufferFile(&sysupgrade, 0);
 149
 150         int kernel_offset = 0x90000; /* offset for the kernel inside the rootfs, default val */
 151         sscanf(argv[2], "%X", &kernel_offset);
 152 #ifdef DEBUG
 153         printf("Kernel_offset: at %X/%i bytes.\n", kernel_offset, kernel_offset);
 154 #endif
 155         char *hwID = argv[3];
 156         char *hwVer = argv[4];
 157         u_int32_t swVer = 0;
 158         sscanf(argv[5],"%4X",&swVer);
 159         swVer = bswap_32(swVer);
 160
 161         char *rootfsname = malloc(2*strlen(sysupgrade.file_name) + 8);
 162         sprintf(rootfsname, "%s.rootfs", sysupgrade.file_name);
 163
 164         char *zipfsname = malloc(2*strlen(rootfsname) + 5);
 165         sprintf(zipfsname, "%s.zip", rootfsname);
 166         /* / Args */
 167
 168 #ifdef DEBUG
 169         printf("Building header: %s %s %2X %s.\n", hwID , hwVer, swVer, magic);
 170 #endif
 171         /* Construct the firmware header/magic */
 172         struct file_info header = {0, 0, 0};
 173         header.file_size = HEADER_SIZE;
 174         header.file_data = malloc(HEADER_SIZE);
 175         bzero(header.file_data, header.file_size);
 176
 177         char *tg = header.file_data;
 178         strcpy(tg, magic);
 179         memcpy(tg+7, version, 4*sizeof(char));
 180         strcpy(tg+11, hwID);
 181         strcpy(tg+45, hwVer);
 182         memcpy(tg+55, &swVer,sizeof(u_int32_t));
 183         strcpy(tg+63, magic);
 184
 185 #ifdef DEBUG
 186         printf("Header done, now creating rootfs.");
 187 #endif
 188         /* Construct a rootfs */
 189         struct file_info rootfs = {0, 0, 0};
 190         rootfs.file_size = sysupgrade.file_size + kernel_offset + footer_size;
 191         rootfs.file_data =  malloc(rootfs.file_size);
 192         bzero(rootfs.file_data, rootfs.file_size);
 193         rootfs.file_name = rootfsname;
 194
 195         /* copy Owrt image to Kernel location */
 196         memcpy(rootfs.file_data+kernel_offset, sysupgrade.file_data, sysupgrade.file_size);
 197
 198         /* 22 added to get away from sysup image, no other reason.
 199          *  updater searches for magic anyway */
 200         tg = rootfs.file_data + kernel_offset + sysupgrade.file_size+22;
 201
 202         memcpy(tg, header.file_data, header.file_size);
 203         writeFile(&rootfs);
 204
 205 #ifdef DEBUG
 206         printf("Preparing to zip.\n");
 207 #endif
 208         /* now that we got the rootfs, repeat the whole thing again(sorta):
 209          * 1. zip the rootfs */
 210         char *zipper = malloc(5 + 2*strlen(rootfs.file_name) + 4);
 211         sprintf(zipper, "%s %s %s", "zip ", zipfsname, rootfs.file_name);
 212         int ret = system(zipper);
 213
 214         /* clear rootfs file */
 215         rmFile(&rootfs);
 216
 217         /* and load zipped fs */
 218         struct file_info zippedfs = {zipfsname, 0, 0};
 219         bufferFile(&zippedfs, 0);
 220
 221 #ifdef DEBUG
 222         printf("Creating Image.\n");
 223 #endif
 224
 225         /* 2. create new file 512+rootfs size */
 226         struct file_info image = {argv[1], 0, 0};
 227         image.file_data = malloc(zippedfs.file_size + 512);
 228         image.file_size = zippedfs.file_size + 512;
 229
 230         /* 3. copy zipfile at loc 512 */
 231         memcpy(image.file_data+512, zippedfs.file_data, zippedfs.file_size);
 232         rmFile(&zippedfs);
 233
 234         /* 4. add header to file */
 235         memcpy(image.file_data, header.file_data, header.file_size);
 236
 237         /* 5. do a checksum run, and compute checksum */
 238         char chksum = getCheckSum(image.file_data, image.file_size);
 239 #ifdef DEBUG
 240         printf("Checksum for Image: %X.\n", chksum);
 241 #endif
 242
 243         /* 6. write the checksum invert into byte 511 to bring it to 0 */
 244         chksum = (chksum ^ 0xFF) + 1;
 245         memcpy(image.file_data+511, &chksum, 1);
 246
 247         chksum = getCheckSum(image.file_data, image.file_size);
 248 #ifdef DEBUG
 249         printf("Checksum for after fix: %X.\n", chksum);
 250 #endif
 251         /* 7. pray that the updater will accept the file */
 252         writeFile(&image);
 253         return 0;
 254 }