Split out unix /dev/random to a RAND_METHOD

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@17098 ec53bebd-3082-4978-b11e-865c3cabbd6b

lib/des/rand.c

@@ -43,74 +43,56 @@ RCSID("$Id$");
 
 #include <roken.h>
 
-const RAND_METHOD *default_meth;
+static RAND_METHOD builtin_rand;
+static const RAND_METHOD *selected_meth = &builtin_rand;
 
-static int
-get_device_fd(int flags)
+void
+RAND_seed(const void *indata, size_t size)
 {
-    static const char *rnd_devices[] = {
-	"/dev/random",
-	"/dev/srandom",
-	"/dev/urandom",
-	"/dev/arandom",
-	NULL
-    };
-    const char **p;
-
-    for(p = rnd_devices; *p; p++) {
-	int fd = open(*p, flags | O_NDELAY);
-	if(fd >= 0)
-	    return fd;
-    }
-    return -1;
+    (*selected_meth->seed)(indata, size);
 }
 
 int
 RAND_bytes(void *outdata, size_t size)
 {
-    ssize_t ret;
-    int fd;
-
-    fd = get_device_fd(O_RDONLY);
-    if (fd < 0)
-	return 0;
-
-    ret = read(fd, outdata, size);
-    close(fd);
-    if (size != ret)
-	return 0;
-
-    return 1;
-}
-
-int
-RAND_pseudo_bytes(void *outdata, size_t num)
-{
-    return RAND_bytes(outdata, num);
+    return (*selected_meth->bytes)(outdata, size);
 }
 
 void
-RAND_seed(const void *indata, size_t size)
+RAND_cleanup(void)
 {
-    int fd = get_device_fd(O_WRONLY);
-    if (fd < 0)
-	return;
+    (*selected_meth->cleanup)();
+}
 
-    write(fd, indata, size);
-    close(fd);
+void
+RAND_add(const void *indata, size_t size, double entropi)
+{
+    (*selected_meth->add)(indata, size, entropi);
+}
+
+int
+RAND_pseudo_bytes(void *outdata, size_t size)
+{
+    return (*selected_meth->pseudorand)(outdata, size);
+}
+
+int
+RAND_status(void)
+{
+    return (*selected_meth->status)();
 }
 
 int
 RAND_set_rand_method(const RAND_METHOD *meth)
 {
-    default_meth = meth;
+    selected_meth = meth;
     return 1;
 }
 
 const RAND_METHOD *
 RAND_get_rand_method(void)
 {
-    return default_meth;
+    return selected_meth;
 }
 
 int
@@ -131,14 +113,109 @@ RAND_write_file(const char *filename)
     return 1;
 }
 
-int
-RAND_status(void)
-{
-    return 1;
-}
-
 int
 RAND_egd(const char *filename)
 {
     return 1;
 }
+
+/*
+ * Unix /dev/random
+ */
+
+static int
+get_device_fd(int flags)
+{
+    static const char *rnd_devices[] = {
+	"/dev/random",
+	"/dev/srandom",
+	"/dev/urandom",
+	"/dev/arandom",
+	NULL
+    };
+    const char **p;
+
+    for(p = rnd_devices; *p; p++) {
+	int fd = open(*p, flags | O_NDELAY);
+	if(fd >= 0)
+	    return fd;
+    }
+    return -1;
+}
+
+static void
+unix_seed(const void *indata, int size)
+{
+    int fd;
+
+    if (size <= 0)
+	return;
+
+    fd = get_device_fd(O_WRONLY);
+    if (fd < 0)
+	return;
+
+    write(fd, indata, size);
+    close(fd);
+
+}
+
+static int 
+unix_bytes(unsigned char *outdata, int size)
+{
+    ssize_t ret;
+    int fd;
+
+    if (size <= 0)
+	return 0;
+
+    fd = get_device_fd(O_RDONLY);
+    if (fd < 0)
+	return 0;
+
+    ret = read(fd, outdata, size);
+    close(fd);
+    if (size != ret)
+	return 0;
+
+    return 1;
+}
+
+static void
+unix_cleanup(void)
+{
+}
+
+static void
+unix_add(const void *indata, int size, double entropi)
+{
+    unix_seed(indata, size);
+}
+
+static int
+unix_pseudorand(unsigned char *outdata, int size)
+{
+    return unix_bytes(outdata, size);
+}
+
+static int
+unix_status(void)
+{
+    int fd;
+
+    fd = get_device_fd(O_RDONLY);
+    if (fd < 0)
+	return 0;
+    close(fd);
+
+    return 1;
+}
+
+static RAND_METHOD builtin_rand = {
+    unix_seed,
+    unix_bytes,
+    unix_cleanup,
+    unix_add,
+    unix_pseudorand,
+    unix_status
+};