diff options
Diffstat (limited to 'tools/firmware-utils/src/dgn3500sum.c')
| -rw-r--r-- | tools/firmware-utils/src/dgn3500sum.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/tools/firmware-utils/src/dgn3500sum.c b/tools/firmware-utils/src/dgn3500sum.c new file mode 100644 index 0000000..00a0c5f --- /dev/null +++ b/tools/firmware-utils/src/dgn3500sum.c @@ -0,0 +1,167 @@ +/* ************************************************************************** + + This program creates a modified 16bit checksum used for the Netgear + DGN3500 series routers. The difference between this and a standard + checksum is that every 0x100 bytes added 0x100 have to be subtracted + from the sum. + + (C) 2013 Marco Antonio Mauro <marcus90 at gmail.com> + + Based on previous unattributed work. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + + ************************************************************************* */ + + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/stat.h> + +unsigned char PidDataWW[70] = +{ + 0x73, 0x45, 0x72, 0x43, 0x6F, 0x4D, 0x6D, 0x00, 0x00, 0x00, 0x00, 0x59, 0x50, 0x35, 0x37, 0x32, + 0x33, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x41, 0x00, 0x37, + 0x32, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x11, 0x00, 0x00, 0x00, 0x00, 0x00, 0x73, + 0x45, 0x72, 0x43, 0x6F, 0x4D, 0x6D, +} ; + +unsigned char PidDataDE[70] = +{ + 0x73, 0x45, 0x72, 0x43, 0x6F, 0x4D, 0x6D, 0x00, 0x00, 0x00, 0x00, 0x59, 0x50, 0x35, 0x37, 0x32, + 0x34, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x42, 0x00, 0x37, + 0x32, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x11, 0x00, 0x00, 0x00, 0x00, 0x00, 0x73, + 0x45, 0x72, 0x43, 0x6F, 0x4D, 0x6D, +} ; + +unsigned char PidDataNA[70] = +{ + 0x73, 0x45, 0x72, 0x43, 0x6F, 0x4D, 0x6D, 0x00, 0x00, 0x00, 0x00, 0x59, 0x50, 0x35, 0x37, 0x32, + 0x36, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x41, 0x00, 0x37, + 0x32, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x11, 0x00, 0x00, 0x00, 0x00, 0x00, 0x73, + 0x45, 0x72, 0x43, 0x6F, 0x4D, 0x6D, +} ; + +/* ******************************************************************* + Reads the file into memory and returns pointer to the buffer. */ +static char *readfile(char *filename, int *size) +{ + FILE *fp; + char *buffer; + struct stat info; + + if (stat(filename,&info)!=0) + return NULL; + + if ((fp=fopen(filename,"r"))==NULL) + return NULL; + + buffer=NULL; + for (;;) + { + if ((buffer=(char *)malloc(info.st_size+1))==NULL) + break; + + if (fread(buffer,1,info.st_size,fp)!=info.st_size) + { + free(buffer); + buffer=NULL; + break; + } + + buffer[info.st_size]='\0'; + if(size) *size = info.st_size; + + break; + } + + (void)fclose(fp); + + return buffer; +} + + +/* ******************************************************************* */ +int main(int argc, char** argv) +{ + unsigned long start, i; + char *endptr, *buffer, *p; + int count; // size of file in bytes + unsigned short sum, sum1; + char sumbuf[9]; + + if(argc < 3) { + printf("ERROR: Argument missing!\n\nUsage %s filename starting offset in hex [PID code]\n\n", argv[0]); + return 1; + } + + + FILE *fp = fopen(argv[1], "a"); + if(!fp) { + printf("ERROR: File not writeable!\n"); + return 1; + } + if(argc = 4) + { + printf("%s: PID type: %s\n", argv[0], argv[3]); + if(strcmp(argv[3], "DE")==0) + fwrite(PidDataDE, sizeof(PidDataDE), sizeof(char), fp); /* write DE pid */ + else if(strcmp(argv[3], "NA")==0) + fwrite(PidDataNA, sizeof(PidDataNA), sizeof(char), fp); /* write NA pid */ + else /* if(strcmp(argv[3], "WW")) */ + fwrite(PidDataWW, sizeof(PidDataWW), sizeof(char), fp); /* write WW pid */ + } + else + fwrite(PidDataWW, sizeof(PidDataWW), sizeof(char), fp); /* write WW pid if unspecified */ + + fclose(fp); + + /* Read the file to calculate the checksums */ + buffer = readfile(argv[1], &count); + if(!buffer) { + printf("ERROR: File %s not found!\n", argv[1]); + return 1; + } + + p = buffer; + for(i = 0; i < count; i++) + { + sum += p[i]; + } + + start = strtol(argv[2], &endptr, 16); + p = buffer+start; + sum1 = 0; + for(i = 0; i < count - start; i++) + { + sum1 += p[i]; + } + + sprintf(sumbuf,"%04X%04X",sum1,sum); + /* Append the 2 checksums to end of file */ + fp = fopen(argv[1], "a"); + if(!fp) { + printf("ERROR: File not writeable!\n"); + return 1; + } + fwrite(sumbuf, 8, sizeof(char), fp); + fclose(fp); + free(buffer); + return 0; +} |