1 files changed, 129 insertions, 0 deletions
diff --git a/src/pulsecore/random.c b/src/pulsecore/random.c
new file mode 100644
index 0000000..508a6f8
--- /dev/null
+++ b/src/pulsecore/random.c
@@ -0,0 +1,129 @@
+/***
+  This file is part of PulseAudio.
+
+  Copyright 2004-2006 Lennart Poettering
+  Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
+
+  PulseAudio is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License as
+  published by the Free Software Foundation; either version 2.1 of the
+  License, or (at your option) any later version.
+
+  PulseAudio is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <time.h>
+
+#ifdef HAVE_WINDOWS_H
+#include <windows.h>
+#include <wincrypt.h>
+#endif
+
+#include <pulsecore/core-util.h>
+#include <pulsecore/log.h>
+#include <pulsecore/macro.h>
+
+#include "random.h"
+
+static bool has_whined = false;
+
+static const char * const devices[] = { "/dev/urandom", "/dev/random", NULL };
+
+static int random_proper(void *ret_data, size_t length) {
+#ifdef OS_IS_WIN32
+    int ret = -1;
+
+    HCRYPTPROV hCryptProv = 0;
+
+    pa_assert(ret_data);
+    pa_assert(length > 0);
+
+    if (CryptAcquireContext(&hCryptProv, NULL, NULL, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT | CRYPT_SILENT)) {
+        if (CryptGenRandom(hCryptProv, length, ret_data))
+            ret = 0;
+        CryptReleaseContext(hCryptProv, 0);
+    }
+
+    return ret;
+
+#else /* OS_IS_WIN32 */
+
+    int fd, ret = -1;
+    ssize_t r = 0;
+    const char *const * device;
+
+    pa_assert(ret_data);
+    pa_assert(length > 0);
+
+    device = devices;
+
+    while (*device) {
+        ret = 0;
+
+        if ((fd = pa_open_cloexec(*device, O_RDONLY, 0)) >= 0) {
+
+            if ((r = pa_loop_read(fd, ret_data, length, NULL)) < 0 || (size_t) r != length)
+                ret = -1;
+
+            pa_close(fd);
+        } else
+            ret = -1;
+
+        if (ret == 0)
+            break;
+
+        device++;
+    }
+
+    return ret;
+#endif /* OS_IS_WIN32 */
+}
+
+void pa_random_seed(void) {
+    unsigned int seed;
+
+    if (random_proper(&seed, sizeof(unsigned int)) < 0) {
+
+        if (!has_whined) {
+            pa_log_warn("Failed to get proper entropy. Falling back to seeding with current time.");
+            has_whined = true;
+        }
+
+        seed = (unsigned int) time(NULL);
+    }
+
+    srand(seed);
+}
+
+void pa_random(void *ret_data, size_t length) {
+    uint8_t *p;
+    size_t l;
+
+    pa_assert(ret_data);
+    pa_assert(length > 0);
+
+    if (random_proper(ret_data, length) >= 0)
+        return;
+
+    if (!has_whined) {
+        pa_log_warn("Failed to get proper entropy. Falling back to unsecure pseudo RNG.");
+        has_whined = true;
+    }
+
+    for (p = ret_data, l = length; l > 0; p++, l--)
+        *p = (uint8_t) rand();
+}