crypto debugging, and several bugfixes

[userv-utils] / ipif / hex.c

/**/

#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <sysexits.h>

#include "hex.h"

const char *tohex(uint8 *data, int len, char *buf) {
  char *p;
  
  for (p= buf;
       len>0;
       len--, data++, p+=2)
    sprintf(p,"%02x",*data);
  return buf;
}

void unhex(const char *what, const char *txt, uint8 *datar, int *lenr,
	   int minlen, int maxlen) {
  int l, v;
  char buf[3], *ep;

  l= strlen(txt);
  if (l%1) { fprintf(stderr,"odd number of hex digits in %s\n",what); exit(EX_DATAERR); }
  l>>=1;
  if (l<minlen) { fprintf(stderr,"too few hex digits in %s\n",what); exit(EX_DATAERR); }
  if (l>maxlen) { fprintf(stderr,"too many hex digits in %s\n",what); exit(EX_DATAERR); }

  if (lenr) *lenr= l;
  while (l) {
    buf[0]= *txt++;
    buf[1]= *txt++;
    buf[2]= 0;
    v= strtoul(buf,&ep,16);
    if (*ep) { fprintf(stderr,"not hex digit in %s: %c\n",what,*ep); exit(EX_DATAERR); }
    *datar++= v;
    l--;
  }
}