tool: add rand.
The rand subcommand outputs entropy to stdout.
Change-Id: I95c2769a1784a8dd4c21efc15009080006d51349
Reviewed-on: https://boringssl-review.googlesource.com/4325
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/tool/CMakeLists.txt b/tool/CMakeLists.txt
index d542f26..67f59a7 100644
--- a/tool/CMakeLists.txt
+++ b/tool/CMakeLists.txt
@@ -8,6 +8,7 @@
const.cc
digest.cc
pkcs12.cc
+ rand.cc
server.cc
speed.cc
tool.cc
diff --git a/tool/rand.cc b/tool/rand.cc
new file mode 100644
index 0000000..ea97bfa
--- /dev/null
+++ b/tool/rand.cc
@@ -0,0 +1,94 @@
+/* Copyright (c) 2015, Google Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
+
+#include <string>
+#include <vector>
+
+#include <stdint.h>
+
+#include <openssl/rand.h>
+
+#include "internal.h"
+
+
+static const struct argument kArguments[] = {
+ {
+ "-hex", kBooleanArgument,
+ "Hex encoded output."
+ },
+ {
+ "", kOptionalArgument, "",
+ },
+};
+
+bool Rand(const std::vector<std::string> &args) {
+ bool forever = true, hex = false;
+ size_t len = 0;
+
+ if (!args.empty()) {
+ std::vector<std::string> args_copy(args);
+ const std::string &last_arg = args.back();
+
+ if (last_arg.size() > 0 && last_arg[0] != '-') {
+ char *endptr;
+ unsigned long long num = strtoull(last_arg.c_str(), &endptr, 10);
+ if (*endptr == 0) {
+ len = num;
+ forever = false;
+ args_copy.pop_back();
+ }
+ }
+
+ std::map<std::string, std::string> args_map;
+ if (!ParseKeyValueArguments(&args_map, args_copy, kArguments)) {
+ PrintUsage(kArguments);
+ return false;
+ }
+
+ hex = args_map.count("-hex") > 0;
+ }
+
+ uint8_t buf[4096];
+ uint8_t hex_buf[8192];
+
+ size_t done = 0;
+ while (forever || done < len) {
+ size_t todo = sizeof(buf);
+ if (!forever && todo > len - done) {
+ todo = len - done;
+ }
+ RAND_bytes(buf, todo);
+ if (hex) {
+ static const char hextable[] = "0123456789abdef";
+ for (unsigned i = 0; i < todo; i++) {
+ hex_buf[i*2] = hextable[buf[i] >> 4];
+ hex_buf[i*2 + 1] = hextable[buf[i] & 0xf];
+ }
+ if (fwrite(hex_buf, todo*2, 1, stdout) != 1) {
+ return false;
+ }
+ } else {
+ if (fwrite(buf, todo, 1, stdout) != 1) {
+ return false;
+ }
+ }
+ done += todo;
+ }
+
+ if (hex && fwrite("\n", 1, 1, stdout) != 1) {
+ return false;
+ }
+
+ return true;
+}
diff --git a/tool/tool.cc b/tool/tool.cc
index 36e3de9..4bd7d1a 100644
--- a/tool/tool.cc
+++ b/tool/tool.cc
@@ -36,6 +36,7 @@
bool SHA512Sum(const std::vector<std::string> &args);
bool DoPKCS12(const std::vector<std::string> &args);
bool Speed(const std::vector<std::string> &args);
+bool Rand(const std::vector<std::string> &args);
typedef bool (*tool_func_t)(const std::vector<std::string> &args);
@@ -57,6 +58,7 @@
{ "sha256sum", SHA256Sum },
{ "sha384sum", SHA384Sum },
{ "sha512sum", SHA512Sum },
+ { "rand", Rand },
{ "", nullptr },
};