From: Vsevolod Stakhov <vsevolod@highsecure.ru>
Date: Fri, 10 Jun 2016 08:27:25 +0000 (+0100)
Subject: [Feature] Add function to generate random hex string
X-Git-Tag: 1.3.0~383
X-Git-Url: https://source.dussan.org/?a=commitdiff_plain;h=42c732f32a45f4f3dbea262eff6b251a839eab15;p=rspamd.git

[Feature] Add function to generate random hex string
---

diff --git a/src/libutil/util.c b/src/libutil/util.c
index 4ce90ba06..212cb7f1b 100644
--- a/src/libutil/util.c
+++ b/src/libutil/util.c
@@ -1875,6 +1875,25 @@ randombytes (guchar *buf, guint64 len)
 	ottery_rand_bytes (buf, (size_t)len);
 }
 
+void
+rspamd_random_hex (guchar *buf, guint64 len)
+{
+	static const gchar hexdigests[16] = "0123456789abcdef";
+	gint64 i;
+
+	g_assert (len > 0);
+
+	ottery_rand_bytes (buf, (len / 2.0 + 0.5));
+
+	for (i = (gint64)len - 1; i >= 0; i -= 2) {
+		buf[i] = hexdigests[buf[i / 2] & 0xf];
+
+		if (i > 0) {
+			buf[i - 1] = hexdigests[(buf[i / 2] >> 4) & 0xf];
+		}
+	}
+}
+
 
 void
 rspamd_ptr_array_free_hard (gpointer p)
diff --git a/src/libutil/util.h b/src/libutil/util.h
index 48e91cb4f..5c0e82a0d 100644
--- a/src/libutil/util.h
+++ b/src/libutil/util.h
@@ -404,6 +404,13 @@ void rspamd_deinit_libs (struct rspamd_external_libs_ctx *ctx);
  */
 guint64 rspamd_hash_seed (void);
 
+/**
+ * Returns random hex string of the specified length
+ * @param buf
+ * @param len
+ */
+void rspamd_random_hex (guchar *buf, guint64 len);
+
 /**
  * Return jittered time value
  */
diff --git a/src/lua/lua_util.c b/src/lua/lua_util.c
index a5b5eac84..272e39463 100644
--- a/src/lua/lua_util.c
+++ b/src/lua/lua_util.c
@@ -324,6 +324,15 @@ LUA_FUNCTION_DEF (util, create_file);
  */
 LUA_FUNCTION_DEF (util, close_file);
 
+/**
+ * @function util.random_hex(size)
+ * Returns random hex string of the specified size
+ *
+ * @param {number} len length of desired string in bytes
+ * @return {string} string with random hex digests
+ */
+LUA_FUNCTION_DEF (util, random_hex);
+
 static const struct luaL_reg utillib_f[] = {
 	LUA_INTERFACE_DEF (util, create_event_base),
 	LUA_INTERFACE_DEF (util, load_rspamd_config),
@@ -358,6 +367,7 @@ static const struct luaL_reg utillib_f[] = {
 	LUA_INTERFACE_DEF (util, unlock_file),
 	LUA_INTERFACE_DEF (util, create_file),
 	LUA_INTERFACE_DEF (util, close_file),
+	LUA_INTERFACE_DEF (util, random_hex),
 	{NULL, NULL}
 };
 
@@ -1470,6 +1480,26 @@ lua_util_close_file (lua_State *L)
 	return 1;
 }
 
+static gint
+lua_util_random_hex (lua_State *L)
+{
+	gchar *buf;
+	gint buflen;
+
+	buflen = lua_tonumber (L, 1);
+
+	if (buflen <= 0) {
+		return luaL_error (L, "invalid arguments");
+	}
+
+	buf = g_malloc (buflen);
+	rspamd_random_hex (buf, buflen);
+	lua_pushlstring (L, buf, buflen);
+	g_free (buf);
+
+	return 1;
+}
+
 static gint
 lua_load_util (lua_State * L)
 {