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Diffstat (limited to 'deps/uv/src/unix/random-devurandom.c')
-rw-r--r--deps/uv/src/unix/random-devurandom.c93
1 files changed, 93 insertions, 0 deletions
diff --git a/deps/uv/src/unix/random-devurandom.c b/deps/uv/src/unix/random-devurandom.c
new file mode 100644
index 0000000000..bfc40d20f8
--- /dev/null
+++ b/deps/uv/src/unix/random-devurandom.c
@@ -0,0 +1,93 @@
+/* Copyright libuv contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "uv.h"
+#include "internal.h"
+
+#include <sys/stat.h>
+#include <unistd.h>
+
+static uv_once_t once = UV_ONCE_INIT;
+static int status;
+
+
+int uv__random_readpath(const char* path, void* buf, size_t buflen) {
+ struct stat s;
+ size_t pos;
+ ssize_t n;
+ int fd;
+
+ fd = uv__open_cloexec(path, O_RDONLY);
+
+ if (fd == -1)
+ return UV__ERR(errno);
+
+ if (fstat(fd, &s)) {
+ uv__close(fd);
+ return UV__ERR(errno);
+ }
+
+ if (!S_ISCHR(s.st_mode)) {
+ uv__close(fd);
+ return UV_EIO;
+ }
+
+ for (pos = 0; pos != buflen; pos += n) {
+ do
+ n = read(fd, (char*) buf + pos, buflen - pos);
+ while (n == -1 && errno == EINTR);
+
+ if (n == -1) {
+ uv__close(fd);
+ return UV__ERR(errno);
+ }
+
+ if (n == 0) {
+ uv__close(fd);
+ return UV_EIO;
+ }
+ }
+
+ uv__close(fd);
+ return 0;
+}
+
+
+static void uv__random_devurandom_init(void) {
+ char c;
+
+ /* Linux's and NetBSD's random(4) man page suggests applications should read
+ * at least once from /dev/random before switching to /dev/urandom in order
+ * to seed the system RNG. Reads from /dev/random can of course block
+ * indefinitely until entropy is available but that's the point.
+ */
+ status = uv__random_readpath("/dev/random", &c, 1);
+}
+
+
+int uv__random_devurandom(void* buf, size_t buflen) {
+ uv_once(&once, uv__random_devurandom_init);
+
+ if (status != 0)
+ return status;
+
+ return uv__random_readpath("/dev/urandom", buf, buflen);
+}