1 files changed, 126 insertions, 0 deletions
diff --git a/src/util/auth.cpp b/src/util/auth.cpp
new file mode 100644
index 000000000..ac5139535
--- /dev/null
+++ b/src/util/auth.cpp
@@ -0,0 +1,126 @@
+/*
+Minetest
+Copyright (C) 2015 est31 <MTest31@outlook.com>
+
+This program 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.
+
+This program 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 this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#include <algorithm>
+#include <string>
+#include "auth.h"
+#include "base64.h"
+#include "sha1.h"
+#include "srp.h"
+#include "string.h"
+
+// Get an sha-1 hash of the player's name combined with
+// the password entered. That's what the server uses as
+// their password. (Exception : if the password field is
+// blank, we send a blank password - this is for backwards
+// compatibility with password-less players).
+std::string translatePassword(const std::string &name,
+	const std::string &password)
+{
+	if (password.length() == 0)
+		return "";
+
+	std::string slt = name + password;
+	SHA1 sha1;
+	sha1.addBytes(slt.c_str(), slt.length());
+	unsigned char *digest = sha1.getDigest();
+	std::string pwd = base64_encode(digest, 20);
+	free(digest);
+	return pwd;
+}
+
+void getSRPVerifier(const std::string &name,
+	const std::string &password, char **salt, size_t *salt_len,
+	char **bytes_v, size_t *len_v)
+{
+	std::string n_name = lowercase(name);
+	srp_create_salted_verification_key(SRP_SHA256, SRP_NG_2048,
+		n_name.c_str(), (const unsigned char *)password.c_str(),
+		password.size(), (unsigned char **)salt, salt_len,
+		(unsigned char **)bytes_v, len_v, NULL, NULL);
+}
+
+// Get a db-ready SRP verifier
+// The salt param is only modifyable by this method so that you can free it
+// if it was allocated. You shouldn't use it for other purposes, as you will
+// need the contents of salt_len too.
+inline static std::string getSRPVerifier(const std::string &name,
+	const std::string &password, char ** salt, size_t salt_len)
+{
+	char * bytes_v = NULL;
+	size_t len_v;
+	getSRPVerifier(name, password, salt, &salt_len,
+		&bytes_v, &len_v);
+	std::string ret_val = encodeSRPVerifier(std::string(bytes_v, len_v),
+		std::string(*salt, salt_len));
+	free(bytes_v);
+	return ret_val;
+}
+
+// Get a db-ready SRP verifier
+std::string getSRPVerifier(const std::string &name,
+	const std::string &password)
+{
+	char * salt = NULL;
+	std::string ret_val = getSRPVerifier(name,
+		password, &salt, 0);
+	free(salt);
+	return ret_val;
+}
+
+// Get a db-ready SRP verifier
+std::string getSRPVerifier(const std::string &name,
+	const std::string &password, const std::string &salt)
+{
+	// The implementation won't change the salt if its set,
+	// therefore we can cast.
+	char *salt_cstr = (char *)salt.c_str();
+	return getSRPVerifier(name, password,
+		&salt_cstr, salt.size());
+}
+
+// Make a SRP verifier db-ready
+std::string encodeSRPVerifier(const std::string &verifier,
+	const std::string &salt)
+{
+	std::ostringstream ret_str;
+	ret_str << "#1#"
+		<< base64_encode((unsigned char*) salt.c_str(), salt.size()) << "#"
+		<< base64_encode((unsigned char*) verifier.c_str(), verifier.size());
+	return ret_str.str();
+}
+
+bool decodeSRPVerifier(const std::string &enc_pwd,
+	std::string *salt, std::string *bytes_v)
+{
+	std::vector<std::string> pwd_components = str_split(enc_pwd, '#');
+
+	if ((pwd_components.size() != 4)
+			|| (pwd_components[1] != "1") // 1 means srp
+			|| !base64_is_valid(pwd_components[2])
+			|| !base64_is_valid(pwd_components[3]))
+		return false;
+
+	std::string salt_str = base64_decode(pwd_components[2]);
+	std::string bytes_v_str = base64_decode(pwd_components[3]);
+	*salt = salt_str;
+	*bytes_v = bytes_v_str;
+	return true;
+
+}