From 0aa812687671531961433fd7ff1b0cb3d8a911cc Mon Sep 17 00:00:00 2001 From: Thomas Schmitt Date: Sun, 19 Oct 2008 17:40:52 +0000 Subject: [PATCH] The make_isohybrid_mbr() function is now part of libisofs development --- xorriso/make_isohybrid_mbr.c | 251 ----------------------------------- 1 file changed, 251 deletions(-) delete mode 100644 xorriso/make_isohybrid_mbr.c diff --git a/xorriso/make_isohybrid_mbr.c b/xorriso/make_isohybrid_mbr.c deleted file mode 100644 index ae139fb8..00000000 --- a/xorriso/make_isohybrid_mbr.c +++ /dev/null @@ -1,251 +0,0 @@ - -#include -#include -#include -#include -#include -#include -#include -#include - -/* for gettimeofday() */ -#include - - -/* This code stems from syslinux-3.72/utils/isohybrid, a perl script - under GPL which is Copyright 2002-2008 H. Peter Anvin. - Line numbers in comments refer to the lines of that script. - It has been analyzed and re-written in C language 2008 by Thomas Schmitt. - As soon as it is part of a libisofs test version, H. Peter Anvin will - be asked about his own copyright claims and/or license tolerance in - respect to this C code. -*/ - - -/* A helper function. One could replace it by one or two macros. */ -static int lsb_to_buf(char **wpt, int value, int bits, int flag) -{ - int b; - - for(b= 0; b < bits; b+= 8) - *((unsigned char *) ((*wpt)++))= (value >> b) & 0xff; - return(1); -} - - -/* Create a MBR for an isohybrid enabled ISOLINUX boot image. - It is assumed that the caller has verified the readiness of the boot image - by checking for 0xfb 0xc0 0x78 0x70 at bytes 0x40 to 0x43 of isolinux.bin. - @param bin_lba The predicted LBA of isolinux.bin within the emerging ISO. - @param img_blocks The predicted number of 2048 byte blocks in the ISO. - It will get rounded up to full MBs and that many blocks - must really be written as ISO 9660 image. - @param mbr A buffer of at least 512 bytes to take the result which is - to be written as the very beginning of the ISO. - @param flag unused yet, submit 0 - @return <0 = fatal, 0 = failed , 1 = ok , 2 = ok with size warning -*/ -int make_isohybrid_mbr(int bin_lba, int *img_blocks, char *mbr, int flag) -{ - /* According to H. Peter Anvin this binary code stems from - syslinux-3.72/mbr/isohdpfx.S - */ - static int mbr_code_size= 271; - static unsigned char mbr_code[271]= { - 0xfa, 0x31, 0xc0, 0x8e, 0xd8, 0x8e, 0xd0, 0xbc, - 0x00, 0x7c, 0x89, 0xe6, 0x06, 0x57, 0x52, 0x8e, - 0xc0, 0xfb, 0xfc, 0xbf, 0x00, 0x06, 0xb9, 0x00, - 0x01, 0xf3, 0xa5, 0xea, 0x20, 0x06, 0x00, 0x00, - 0x52, 0xb4, 0x41, 0xbb, 0xaa, 0x55, 0x31, 0xc9, - 0x30, 0xf6, 0xf9, 0xcd, 0x13, 0x72, 0x14, 0x81, - 0xfb, 0x55, 0xaa, 0x75, 0x0e, 0x83, 0xe1, 0x01, - 0x74, 0x09, 0x66, 0xc7, 0x06, 0xb4, 0x06, 0xb4, - 0x42, 0xeb, 0x15, 0x5a, 0x51, 0xb4, 0x08, 0xcd, - 0x13, 0x83, 0xe1, 0x3f, 0x51, 0x0f, 0xb6, 0xc6, - - 0x40, 0x50, 0xf7, 0xe1, 0x52, 0x50, 0xbb, 0x00, - 0x7c, 0xb9, 0x04, 0x00, 0x66, 0xa1, 0xb0, 0x07, - 0xe8, 0x40, 0x00, 0x72, 0x74, 0x66, 0x40, 0x80, - 0xc7, 0x02, 0xe2, 0xf4, 0x66, 0x81, 0x3e, 0x40, - 0x7c, 0xfb, 0xc0, 0x78, 0x70, 0x75, 0x07, 0xfa, - 0xbc, 0xf4, 0x7b, 0xe9, 0xc6, 0x75, 0xe8, 0x79, - 0x00, 0x69, 0x73, 0x6f, 0x6c, 0x69, 0x6e, 0x75, - 0x78, 0x2e, 0x62, 0x69, 0x6e, 0x20, 0x6d, 0x69, - 0x73, 0x73, 0x69, 0x6e, 0x67, 0x20, 0x6f, 0x72, - 0x20, 0x63, 0x6f, 0x72, 0x72, 0x75, 0x70, 0x74, - - 0x2e, 0x0d, 0x0a, 0x66, 0x60, 0x66, 0x31, 0xd2, - 0x66, 0x52, 0x66, 0x50, 0x06, 0x53, 0x6a, 0x01, - 0x6a, 0x10, 0x89, 0xe6, 0x66, 0xf7, 0x36, 0xf0, - 0x7b, 0xc0, 0xe4, 0x06, 0x88, 0xe1, 0x88, 0xc5, - 0x92, 0xf6, 0x36, 0xf6, 0x7b, 0x88, 0xc6, 0x08, - 0xe1, 0x41, 0xb8, 0x01, 0x02, 0x8a, 0x16, 0xfa, - 0x7b, 0xcd, 0x13, 0x8d, 0x64, 0x10, 0x66, 0x61, - 0xc3, 0xe8, 0x1e, 0x00, 0x4f, 0x70, 0x65, 0x72, - 0x61, 0x74, 0x69, 0x6e, 0x67, 0x20, 0x73, 0x79, - 0x73, 0x74, 0x65, 0x6d, 0x20, 0x6c, 0x6f, 0x61, - - 0x64, 0x20, 0x65, 0x72, 0x72, 0x6f, 0x72, 0x2e, - 0x0d, 0x0a, 0x5e, 0xac, 0xb4, 0x0e, 0x8a, 0x3e, - 0x62, 0x04, 0xb3, 0x07, 0xcd, 0x10, 0x3c, 0x0a, - 0x75, 0xf1, 0xcd, 0x18, 0xf4, 0xeb, 0xfd - }; - - static int h= 64, s= 32; - - int i, warn_size= 0, id; - char *wpt; - off_t imgsize, cylsize, frac, padding, c, cc; - - /* For generating a weak random number */ - struct timeval tv; - struct timezone tz; - - if(bin_lba < 0 || bin_lba >= (1 << 29)) - return(0); /* 1 TB limit of signed 32 bit addressing of 512 byte blocks */ - -/* - 84: Gets size of image in bytes. - 89: -*/ - imgsize= ((off_t) *img_blocks) * (off_t) 2048; - -/* - 90: Computes $padding, size of padded image and number $c of - pseudo-cylinders ($h and $s are constants set in line 24). -102: $cc is $c curbed to 1024. -*/ - cylsize= h * s * 512; - frac= imgsize % cylsize; - padding= (frac > 0 ? cylsize - frac : 0); - imgsize+= padding; - *img_blocks= imgsize / (off_t) 2048; - c= imgsize / cylsize; - if(c > 1024) { - warn_size= 1; - cc= 1024; - } else - cc= c; - -/* -107: Brings the hex-encoded bytes from the file __END__ into -113: the MBR buffer. (This function holds them in mbr_code[].) -*/ - for(i= 0; i < mbr_code_size; i++) - mbr[i]= mbr_code[i]; - -/* -118: Pads up to 432 -*/ - for(i= mbr_code_size; i < 432; i++) - mbr[i]= 0; - - /* From here on use write cursor wpt */ - wpt= mbr + 432; - -/* -120: Converts LBA of isolinux.bin to blocksize 512 and writes - to buffer. Appends 4 zero bytes. -*/ - lsb_to_buf(&wpt, bin_lba * 4, 32, 0); - lsb_to_buf(&wpt, 0, 32, 0); - -/* -121: I do not understand where $id should eventually come - from. An environment variable ? -125: Whatever, i use some 32-bit random value with no crypto strength. -*/ - gettimeofday(&tv, &tz); - id= 0xffffffff & (tv.tv_sec ^ (tv.tv_usec * 2000)); - -/* <<< for comparison with the perl script only - id= 1234567890; -*/ - -/* -126: Adds 4 id bytes and 2 zero bytes. -*/ - lsb_to_buf(&wpt, id, 32, 0); - lsb_to_buf(&wpt, 0, 16, 0); - - -/* -129: Composes 16 byte record from the parameters determined -147: so far. Appends it to buffer and add 48 zero bytes. -*/ - /* There are 4 "partition slots". Only the first is non-zero here. - In the perl script, the fields are set in variables and then - written to buffer. I omit the variables. - */ - /* 0x80 */ - lsb_to_buf(&wpt, 0x80, 8, 0); - /* bhead */ - lsb_to_buf(&wpt, 0, 8, 0); - /* bsect */ - lsb_to_buf(&wpt, 1, 8, 0); - /* bcyl */ - lsb_to_buf(&wpt, 0, 8, 0); - /* fstype */ - lsb_to_buf(&wpt, 0x83, 8, 0); - /* ehead */ - lsb_to_buf(&wpt, h - 1, 8, 0); - /* esect */ - lsb_to_buf(&wpt, s + (((cc - 1) & 0x300) >> 2), 8, 0); - /* ecyl */ - lsb_to_buf(&wpt, (cc - 1) & 0xff, 8, 0); - /* 0 */ - lsb_to_buf(&wpt, 0, 32, 0); - /* psize */ - lsb_to_buf(&wpt, c * h * s, 32, 0); - - /* Fill the other three slots with zeros */ - for(i= 0; i < 3 * 4; i++) - lsb_to_buf(&wpt,0, 32, 0); - -/* -148: Appends bytes 0x55 , 0xAA. -*/ - lsb_to_buf(&wpt, 0x55, 8, 0); - lsb_to_buf(&wpt, 0xaa, 8, 0); - - return(1); -} - - -int main(int argc, char **argv) -{ - int ret, bin_lba= 10000, img_blocks= 100000; - char mbr[513]; - - /* setting up fly paper */ - mbr[511]= mbr[512]= 0x40; - - ret= make_isohybrid_mbr(bin_lba, &img_blocks, mbr, 0); - - /* looking for flies on paper */ - printf("aa,40 <-> %-2.2x,%-2.2x\n", - (unsigned int) ((unsigned char *) mbr)[511], - (unsigned int) ((unsigned char *) mbr)[512]); - - if(ret <= 0) - exit(1); - -/* <<< for comparison with the perl script only -{ - FILE *fp; - - fp= fopen("/u/test/mbr_make_isohybrid_mbr", "w"); - if(fp == NULL) { - perror("make_isohybrid_mbr"); - exit(2); - } - fwrite(mbr, 512, 1, fp); - fclose(fp); -} -*/ - - exit(0); -} - - -