freebsd-nq/libntp/hextoint.c
Ollivier Robert 2b45e011ca Virgin import of ntpd 4.2.6p5.
When the series of commits is complete, things like
https://cert.litnet.lt/en/docs/ntp-distributed-reflection-dos-attacks
should be fixed.

PR:		bin/148836 (except that we import a newer version)
Asked by:	Too many
MFC after:	2 weeks
2013-12-04 21:33:17 +00:00

42 lines
638 B
C

/*
* hextoint - convert an ascii string in hex to an unsigned
* long, with error checking
*/
#include <ctype.h>
#include "ntp_stdlib.h"
int
hextoint(
const char *str,
u_long *pu
)
{
register u_long u;
register const char *cp;
cp = str;
if (*cp == '\0')
return 0;
u = 0;
while (*cp != '\0') {
if (!isxdigit(*cp))
return 0;
if (u & 0xF0000000)
return 0; /* overflow */
u <<= 4;
if ('0' <= *cp && *cp <= '9')
u += *cp++ - '0';
else if ('a' <= *cp && *cp <= 'f')
u += *cp++ - 'a' + 10;
else if ('A' <= *cp && *cp <= 'F')
u += *cp++ - 'A' + 10;
else
return 0;
}
*pu = u;
return 1;
}