Schulzrinne, et al Standards Track [Page 66]
RFC 1889 RTP January 1996
/*
* Generate a random 32-bit quantity.
*/
#include <sys/types.h> /* u_long */
#include <sys/time.h> /* gettimeofday() */
#include <unistd.h> /* get..() */
#include <stdio.h> /* printf() */
#include <time.h> /* clock() */
#include <sys/utsname.h> /* uname() */
#include "global.h" /* from RFC 1321 */
#include "md5.h" /* from RFC 1321 */
#define MD_CTX MD5_CTX
#define MDInit MD5Init
#define MDUpdate MD5Update
#define MDFinal MD5Final
static u_long md_32(char *string, int length)
{
MD_CTX context;
union {
char c[16];
u_long x[4];
} digest;
u_long r;
int i;
MDInit (&context);
MDUpdate (&context, string, length);
MDFinal ((unsigned char *)&digest, &context);
r = 0;
for (i = 0; i < 3; i++) {
r ^= digest.x[i];
}
return r;
} /* md_32 */
/*
* Return random unsigned 32-bit quantity. Use 'type' argument if you
* need to generate several different values in close succession.
*/
u_int32 random32(int type)
{
struct {
int type;
struct timeval tv;
clock_t cpu;
Schulzrinne, et al Standards Track [Page 67]
RFC 1889 RTP January 1996
pid_t pid;
u_long hid;
uid_t uid;
gid_t gid;
struct utsname name;
} s;
gettimeofday(&s.tv, 0);
uname(&s.name);
s.type = type;
s.cpu = clock();
s.pid = getpid();
s.hid = gethostid();
s.uid = getuid();
s.gid = getgid();