libreboot-utils: replace rlong() with rset()

now you can send an arbitrary number of bytes
with random numbers

Signed-off-by: Leah Rowe <leah@libreboot.org>

util/libreboot-utils/include/common.h

@@ -384,7 +384,7 @@ int dcat(const char *s, size_t n,
  */
 
 unsigned short hextonum(char ch_s);
-size_t rlong(void);
+void rset(void *buf, size_t n);
 
 /* Helper functions for command: dump
  */

util/libreboot-utils/lib/mkhtemp.c

@@ -635,12 +635,6 @@ mkhtemp(int *fd,
 		    p, xc, fd, st, type);
 
 		if (r == 0) {
-			if (retries >= MKHTEMP_SPIN_THRESHOLD) {
-				/* usleep can return EINTR */
-				close_errno = errno;
-				usleep((useconds_t)rlong() & 0x3FF);
-				errno = close_errno;
-			}
 			continue;
 		}
 		if (r < 0)
@@ -903,12 +897,7 @@ mkhtemp_fill_random(char *p, size_t xc)
 	for (chx = 0; chx < xc; chx++) {
 
 retry_rand:
-		/* /dev/urandom if enabled, OR:
+		rset(&r, sizeof(r));
-		   * on bsd: uses arc4random
-		   * on linux: uses getrandom
-		   NOTE: *aborts* on error, regardless of method
-		 */
-		r = rlong(); /* always *returns* successfully */
 		if (r >= limit)
 			goto retry_rand;
 

util/libreboot-utils/lib/num.c

@@ -84,7 +84,7 @@ hextonum(char ch_s)
 
 	if (ch == '?' || ch == 'x') {
 
-		rval = rlong();
+		rset(&rval, sizeof(rval));
 		if (errno > 0)
 			goto err_hextonum;
 

util/libreboot-utils/lib/rand.c

@@ -29,23 +29,21 @@
 
 #include "../include/common.h"
 
-size_t
+void
-rlong(void)
+rset(void *buf, size_t n)
 {
 	int saved_errno = errno;
-	size_t len = sizeof(size_t);
 
 #if (defined(__OpenBSD__) || defined(__FreeBSD__) || \
     defined(__NetBSD__) || defined(__APPLE__) || \
     defined(__DragonFly__)) && !(defined(USE_URANDOM) && \
     ((USE_URANDOM) > 0))
 
-	arc4random_buf(&rval, len);
+	arc4random_buf(buf, n);
 	goto out;
 #else
 	size_t off = errno = 0;
 	ssize_t rc = 0;
-	size_t rval;
 
 #if defined(USE_URANDOM) && \
     ((USE_URANDOM) > 0)
@@ -54,11 +52,11 @@ rlong(void)
 	if ((fd = open("/dev/urandom", O_RDONLY)) < 0)
 		goto err;
 retry_rand:
-	if ((rc = read(fd, &rval, len)) < 0) {
+	if ((rc = read(fd, buf, n)) < 0) {
 #elif defined(__linux__)
 retry_rand:
 	if ((rc = (ssize_t)syscall(SYS_getrandom,
-	    (char *)&rval + off, len - off, 0)) < 0) {
+	    buf + off, n - off, 0)) < 0) {
 #else
 #error Unsupported operating system (possibly unsecure randomisation)
 #endif
@@ -72,21 +70,17 @@ retry_rand:
 		goto err; /* possibly unsupported by kernel */
 	}
 
-	if ((off += (size_t)rc) < len)
+	if ((off += (size_t)rc) < n)
 		goto retry_rand;
 
 	goto out;
-
 err:
 	err_no_cleanup(1, ECANCELED,
 	    "Randomisation failure, possibly unsupported in your kernel.");
 	exit(EXIT_FAILURE);
-
-	return 0;
 #endif
 
 out:
 	errno = saved_errno;
-	return rval;
 }
 #endif