1 files changed, 43 insertions, 37 deletions

diff --git a/util/libreboot-utils/lib/rand.c b/util/libreboot-utils/lib/rand.c
index adfad3d7..bf090b43 100644
--- a/util/libreboot-utils/lib/rand.c
+++ b/util/libreboot-utils/lib/rand.c
@@ -4,27 +4,30 @@
  * Random number generation
  */
 
-#ifndef RAND_H
-#define RAND_H
+#if defined(USE_ARC4) && \
+    ((USE_ARC4) > 0)
+#define _DEFAULT_SOURCE 1 /* for arc4random on *linux* */
+			/* (not needed on bsd - on bsd,
+			   it is used automatically unless
+			   overridden with USE_URANDOM */
+#elif defined(USE_URANDOM) && \
+    ((USE_URANDOM) > 0)
+#include <fcntl.h> /* if not arc4random: /dev/urandom */
+#elif defined(__linux__) && \
+    !(defined(USE_ARC4) && ((USE_ARC4) > 0))
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE 1
+#endif
+#include <sys/syscall.h>
+#include <sys/random.h>
+#endif
 
 #ifdef __OpenBSD__
 #include <sys/param.h>
 #endif
 #include <sys/types.h>
 
-#ifndef USE_URANDOM
-#define USE_URANDOM 0
-#endif
-
 #include <errno.h>
-#if defined(USE_URANDOM) && \
-    ((USE_URANDOM) > 0)
-#include <fcntl.h> /* if not arc4random: /dev/urandom */
-#elif defined(__linux__)
-#include <sys/random.h>
-#include <sys/syscall.h>
-#endif
-
 #include <fcntl.h>
 #include <limits.h>
 #include <stddef.h>
@@ -107,7 +110,7 @@ rsize(size_t n)
 {
 	size_t rval = SIZE_MAX;
 	if (!n)
-		err_exit(EFAULT, "rsize: division by zero");
+		exitf("rsize: division by zero");
 
 	/* rejection sampling (clamp rand to eliminate modulo bias) */
 	for (; rval >= SIZE_MAX - (SIZE_MAX % n); rset(&rval, sizeof(rval)));
@@ -133,62 +136,65 @@ rset(void *buf, size_t n)
 		goto err;
 
 	if (n == 0)
-		err_exit(EPERM, "rset: zero-byte request");
+		exitf("rset: zero-byte request");
 
-#if (defined(__OpenBSD__) || defined(__FreeBSD__) || \
+/* on linux, getrandom is recommended,
+   but you can pass -DUSE_ARC4=1 to use arc4random.
+   useful for portability testing from linux.
+ */
+#if (defined(USE_ARC4) && ((USE_ARC4) > 0)) || \
+    ((defined(__OpenBSD__) || defined(__FreeBSD__) || \
     defined(__NetBSD__) || defined(__APPLE__) || \
     defined(__DragonFly__)) && !(defined(USE_URANDOM) && \
-    ((USE_URANDOM) > 0))
+    ((USE_URANDOM) > 0)))
 
 	arc4random_buf(buf, n);
 #else
 	size_t off = 0;
 
-retry_rand:
+retry_rand: {
 
 #if defined(USE_URANDOM) && \
     ((USE_URANDOM) > 0)
-	ssize_t rc;
+	ssize_t rval;
 	int fd = -1;
 
 	open_file_on_eintr("/dev/urandom", &fd, O_RDONLY, 0400, NULL);
 
 	while (rw_retry(saved_errno,
-		rc = read_on_eintr(fd,
-		    (unsigned char *)buf + off, n - off, 0)));
+	    rval = rw(fd, (unsigned char *)buf + off, n - off, 0, IO_READ)));
 #elif defined(__linux__)
-	long rc;
+	long rval;
 	while (sys_retry(saved_errno,
-		rc = syscall(SYS_getrandom,
+		rval = syscall(SYS_getrandom,
 		    (unsigned char *)buf + off, n - off, 0)));
 #else
 #error Unsupported operating system (possibly unsecure randomisation)
 #endif
 
-	if (rc < 0)
-		goto err; /* syscall fehler */
-
-	if (rc == 0)
-		goto err; /* prevent infinite loop on fatal err */
+	if (rval < 0 || /* syscall fehler */
+	    rval == 0) { /* prevent infinite loop on fatal err */
+#if defined(USE_URANDOM) && \
+    ((USE_URANDOM) > 0)
+		xclose(&fd);
+#endif
+		goto err;
+	}
 
-	if ((off += (size_t)rc) < n)
+	if ((off += (size_t)rval) < n)
 		goto retry_rand;
 
 #if defined(USE_URANDOM) && \
     ((USE_URANDOM) > 0)
-	close_on_eintr(&fd);
+	xclose(&fd);
 #endif
+}
 
 #endif
 	reset_caller_errno(0);
 	return;
 err:
-#if defined(USE_URANDOM) && \
-    ((USE_URANDOM) > 0)
-	close_on_eintr(&fd);
-#endif
 	(void) with_fallback_errno(ECANCELED);
-	err_exit(errno, "Randomisierungsfehler");
+	exitf("Randomisierungsfehler");
 	exit(EXIT_FAILURE);
 }
-#endif