tools/firmware-utils/src/mkdapimg.c

   1 #include <stdio.h>
   2 #include <stdint.h>
   3 #include <stdlib.h>
   4 #include <unistd.h>
   5 #include <libgen.h>
   6 #include <stdarg.h>
   7 #include <getopt.h>
   8 #include <string.h>
   9 #include <errno.h>
  10
  11 #include <netinet/in.h> // htonl
  12
  13 // Usage: mkdapimg [-p] [-m <model>] -s <sig> -i <input> -o <output>
  14 //
  15 // e.g.: mkdapimg -s RT3052-AP-DAP1350-3 -i sysupgarde.bin -o factory.bin
  16 //
  17 // If the model string <model> is not given, we will assume that
  18 // the leading characters upto the first "-" is the model.
  19 //
  20 // The "-p" (patch) option is used to patch the exisiting image with the
  21 // specified model and signature.
  22 // The "-x" (fix) option will recalculate the payload size and checksum
  23 // during the patch mode operation.
  24
  25 // The img_hdr_struct was taken from the D-Link SDK:
  26 // DAP-1350_A1_FW1.11NA_GPL/GPL_Source_Code/Uboot/DAP-1350/httpd/header.h
  27
  28 #define MAX_MODEL_NAME_LEN      20
  29 #define MAX_SIG_LEN             30
  30
  31 struct img_hdr_struct {
  32         uint32_t checksum;
  33         char model[MAX_MODEL_NAME_LEN];
  34         char sig[MAX_SIG_LEN];
  35         uint8_t partition;
  36         uint8_t hdr_len;
  37         uint8_t rsv1;
  38         uint8_t rsv2;
  39         uint32_t flash_byte_cnt;
  40 } imghdr ;
  41
  42 char *progname;
  43
  44 void
  45 perrexit(int code, char *msg)
  46 {
  47         fprintf(stderr, "%s: %s: %s\n", progname, msg, strerror(errno));
  48         exit(code);
  49 }
  50
  51 void
  52 usage()
  53 {
  54         fprintf(stderr, "usage: %s [-p] [-m model] -s signature -i input -o output\n", progname);
  55         exit(1);
  56 }
  57
  58 int
  59 main(int ac, char *av[])
  60 {
  61         char model[MAX_MODEL_NAME_LEN+1];
  62         char signature[MAX_SIG_LEN+1];
  63         int patchmode = 0;
  64         int fixmode = 0;
  65
  66         FILE *ifile, *ofile;
  67         int c;
  68         uint32_t cksum;
  69         uint32_t bcnt;
  70
  71         progname = basename(av[0]);
  72         memset(model, 0, sizeof(model));
  73         memset(signature, 0, sizeof(signature));
  74
  75         while ( 1 ) {
  76                 int c;
  77
  78                 c = getopt(ac, av, "pxm:s:i:o:");
  79                 if (c == -1)
  80                         break;
  81
  82                 switch (c) {
  83                 case 'p':
  84                         patchmode = 1;
  85                         break;
  86                 case 'x':
  87                         fixmode = 1;
  88                         break;
  89                 case 'm':
  90                         if (strlen(optarg) > MAX_MODEL_NAME_LEN) {
  91                                 fprintf(stderr, "%s: model name exceeds %d chars\n",
  92                                         progname, MAX_MODEL_NAME_LEN);
  93                                 exit(1);
  94                         }
  95                         strcpy(model, optarg);
  96                         break;
  97                 case 's':
  98                         if (strlen(optarg) > MAX_SIG_LEN) {
  99                                 fprintf(stderr, "%s: signature exceeds %d chars\n",
 100                                         progname, MAX_SIG_LEN);
 101                                 exit(1);
 102                         }
 103                         strcpy(signature, optarg);
 104                         break;
 105                 case 'i':
 106                         if ((ifile = fopen(optarg, "r")) == NULL)
 107                                 perrexit(1, optarg);
 108                         break;
 109                 case 'o':
 110                         if ((ofile = fopen(optarg, "w")) == NULL)
 111                                 perrexit(1, optarg);
 112                         break;
 113                 default:
 114                         usage();
 115                 }
 116         }
 117
 118         if (signature[0] == 0 || ifile == NULL || ofile == NULL) {
 119                 usage();
 120         }
 121
 122         if (model[0] == 0) {
 123                 char *p = strchr(signature, '-');
 124                 if (p == NULL) {
 125                         fprintf(stderr, "%s: model name unknown\n", progname);
 126                         exit(1);
 127                 }
 128                 if (p - signature > MAX_MODEL_NAME_LEN) {
 129                         *p = 0;
 130                         fprintf(stderr, "%s: auto model name failed, string %s too long\n", progname, signature);
 131                         exit(1);
 132                 }
 133                 strncpy(model, signature, p - signature);
 134         }
 135
 136         if (patchmode) {
 137                 if (fread(&imghdr, sizeof(imghdr), 1, ifile) < 0)
 138                         perrexit(2, "fread on input");
 139         }
 140
 141         for (bcnt = 0, cksum = 0 ; (c = fgetc(ifile)) != EOF ; bcnt++)
 142                 cksum += c & 0xff;
 143
 144         if (fseek(ifile, patchmode ? sizeof(imghdr) : 0, SEEK_SET) < 0)
 145                 perrexit(2, "fseek on input");
 146
 147         if (patchmode == 0) {
 148                 // Fill in the header
 149                 memset(&imghdr, 0, sizeof(imghdr));
 150                 imghdr.checksum = htonl(cksum);
 151                 imghdr.partition = 0 ; // don't care?
 152                 imghdr.hdr_len = sizeof(imghdr);
 153                 imghdr.flash_byte_cnt = htonl(bcnt);
 154         } else {
 155                 if (ntohl(imghdr.checksum) != cksum) {
 156                         fprintf(stderr, "%s: patch mode, checksum mismatch\n",
 157                                 progname);
 158                         if (fixmode) {
 159                                 fprintf(stderr, "%s: fixing\n", progname);
 160                                 imghdr.checksum = htonl(cksum);
 161                         } else
 162                                 exit(3);
 163                 } else if (ntohl(imghdr.flash_byte_cnt) != bcnt) {
 164                         fprintf(stderr, "%s: patch mode, size mismatch\n",
 165                                 progname);
 166                         if (fixmode) {
 167                                 fprintf(stderr, "%s: fixing\n", progname);
 168                                 imghdr.flash_byte_cnt = htonl(bcnt);
 169                         } else
 170                                 exit(3);
 171                 }
 172         }
 173
 174         strncpy(imghdr.model, model, MAX_MODEL_NAME_LEN);
 175         strncpy(imghdr.sig, signature, MAX_SIG_LEN);
 176
 177         if (fwrite(&imghdr, sizeof(imghdr), 1, ofile) < 0)
 178                 perrexit(2, "fwrite header on output");
 179
 180         while ((c = fgetc(ifile)) != EOF) {
 181                 if (fputc(c, ofile) == EOF)
 182                         perrexit(2, "fputc on output");
 183         }
 184
 185         if (ferror(ifile))
 186                 perrexit(2, "fgetc on input");
 187
 188
 189         fclose(ofile);
 190         fclose(ifile);
 191 }