TTCN-3 native function wrapper for SNOW-3G

Change-Id: I7fca69ea8b4aed48d5a64885b762ab85be71ef03
diff --git a/mme/LTE_CryptoFunctionDefs.cc b/mme/LTE_CryptoFunctionDefs.cc
new file mode 100644
index 0000000..da2d521
--- /dev/null
+++ b/mme/LTE_CryptoFunctionDefs.cc
@@ -0,0 +1,189 @@
+/* Utility functions from ogslib imported to TTCN-3
+ *
+ * (C) 2019 Harald Welte <laforge@gnumonks.org>
+ * All rights reserved.
+ *
+ * Released under the terms of GNU General Public License, Version 2 or
+ * (at your option) any later version.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <stdint.h>
+
+#include <Boolean.hh>
+#include <Integer.hh>
+#include <Octetstring.hh>
+#include <Bitstring.hh>
+
+#include "snow-3g.h"
+#include "key_derivation.h"
+
+//#define DEBUG
+
+#ifdef DEBUG
+static __thread char hexd_buff[4096];
+static const char hex_chars[] = "0123456789abcdef";
+
+static const char *_osmo_hexdump_buf(char *out_buf, size_t out_buf_size, const unsigned char *buf, int len, const char *delim,
+			     bool delim_after_last)
+{
+	int i;
+	char *cur = out_buf;
+	size_t delim_len;
+
+	if (!out_buf || !out_buf_size)
+		return "";
+
+	delim = delim ? : "";
+	delim_len = strlen(delim);
+
+	for (i = 0; i < len; i++) {
+		const char *delimp = delim;
+		int len_remain = out_buf_size - (cur - out_buf) - 1;
+		if (len_remain < (2 + delim_len)
+		    && !(!delim_after_last && i == (len - 1) && len_remain >= 2))
+			break;
+
+		*cur++ = hex_chars[buf[i] >> 4];
+		*cur++ = hex_chars[buf[i] & 0xf];
+
+		if (i == (len - 1) && !delim_after_last)
+			break;
+
+		while (len_remain > 1 && *delimp) {
+			*cur++ = *delimp++;
+			len_remain--;
+		}
+	}
+	*cur = '\0';
+	return out_buf;
+}
+
+static char *_osmo_hexdump(const unsigned char *buf, int len)
+{
+	_osmo_hexdump_buf(hexd_buff, sizeof(hexd_buff), buf, len, "", true);
+	return hexd_buff;
+}
+#endif
+
+namespace LTE__CryptoFunctions {
+
+
+/* f8.
+* Input key: 128 bit Confidentiality Key as OCT16.
+* Input count:32-bit Count, Frame dependent input as INTEGER.
+* Input bearer: 5-bit Bearer identity (in the LSB side) as BIT5.
+* Input is_dlwnlink: Direction of transmission.
+* Input data: length number of bits, input bit stream as OCTETSTRING.
+* Output data: Output bit stream. Assumes data is suitably memory
+* allocated.
+* Encrypts/decrypts blocks of data between 1 and 2^32 bits in length as
+* defined in Section 3.
+*/
+OCTETSTRING f__snow__3g__f8(const OCTETSTRING& key, const INTEGER& count, const INTEGER & bearer,
+			    const BOOLEAN& is_downlink, const OCTETSTRING& data)
+{
+	TTCN_Buffer ttcn_buf_data(data);
+	TTCN_Buffer ttcn_buf_key(key);
+	uint32_t direction = (uint32_t)is_downlink;
+
+	snow_3g_f8((u8 *)ttcn_buf_key.get_data(), (u32) count, (u32)bearer, direction,
+		   (u8 *)ttcn_buf_data.get_data(), ttcn_buf_data.get_len());
+
+	return OCTETSTRING(ttcn_buf_data.get_len(), ttcn_buf_data.get_data());
+}
+
+/* f9.
+* Input key: 128 bit Integrity Key as OCT16.
+* Input count:32-bit Count, Frame dependent input as UINT32.
+* Input fresh: 32-bit Random number as UINT32.
+* Input is_downlink:1 Direction of transmission.
+* Input data: input bit stream.
+* Output : 32 bit block used as MAC
+* Generates 32-bit MAC using UIA2 algorithm as defined in Section 4.
+*/
+
+OCTETSTRING f__snow__3g__f9(const OCTETSTRING& key, const INTEGER& count, const INTEGER& fresh,
+			    const BOOLEAN& is_downlink, const OCTETSTRING& data)
+{
+	TTCN_Buffer ttcn_buf_data(data);
+	TTCN_Buffer ttcn_buf_key(key);
+	uint32_t direction = (uint32_t)is_downlink;
+	uint8_t tmp[4];
+	TTCN_Buffer ttcn_buf_mac;
+
+#ifdef DEBUG
+	printf("F9: key=%s, count=%u, fresh=%u, direction=%u, ",
+		_osmo_hexdump((u8 *)ttcn_buf_key.get_data(), ttcn_buf_key.get_len()), (u32) count,
+		(u32) fresh, direction);
+	printf("data=%s -> ", _osmo_hexdump(ttcn_buf_data.get_data(), ttcn_buf_data.get_len()));
+#endif
+	snow_3g_f9((u8 *)ttcn_buf_key.get_data(), (u32) count, (u32) fresh, direction,
+		   (u8 *)ttcn_buf_data.get_data(), ttcn_buf_data.get_len()*8, tmp);
+#ifdef DEBUG
+	printf("%s\n", _osmo_hexdump(tmp, sizeof(tmp)));
+#endif
+
+	return OCTETSTRING(4, tmp);
+}
+
+OCTETSTRING f__kdf__kasme(const OCTETSTRING& ck, const OCTETSTRING& ik, const OCTETSTRING& plmn_id,
+			  const OCTETSTRING& sqn, const OCTETSTRING& ak)
+{
+	TTCN_Buffer ttcn_buf_ck(ck);
+	TTCN_Buffer ttcn_buf_ik(ik);
+	TTCN_Buffer ttcn_buf_plmn_id(plmn_id);
+	TTCN_Buffer ttcn_buf_sqn(sqn);
+	TTCN_Buffer ttcn_buf_ak(ak);
+	uint8_t kasme[32];
+
+	hss_auc_kasme(ttcn_buf_ck.get_data(), ttcn_buf_ik.get_data(), ttcn_buf_plmn_id.get_data(),
+			ttcn_buf_sqn.get_data(), ttcn_buf_ak.get_data(), kasme);
+	return OCTETSTRING(sizeof(kasme), kasme);
+}
+
+OCTETSTRING f__kdf__nas__int(const INTEGER& alg_id, const OCTETSTRING &kasme)
+{
+	TTCN_Buffer ttcn_buf_kasme(kasme);
+	uint8_t knas[16];
+
+	mme_kdf_nas(MME_KDF_NAS_INT_ALG, (int)alg_id, (const u8*) ttcn_buf_kasme.get_data(), knas);
+	return OCTETSTRING(sizeof(knas), knas);
+}
+
+OCTETSTRING f__kdf__nas__enc(const INTEGER& alg_id, const OCTETSTRING &kasme)
+{
+	TTCN_Buffer ttcn_buf_kasme(kasme);
+	uint8_t knas[16];
+
+	mme_kdf_nas(MME_KDF_NAS_ENC_ALG, (int)alg_id, (const u8*) ttcn_buf_kasme.get_data(), knas);
+	return OCTETSTRING(sizeof(knas), knas);
+}
+
+
+OCTETSTRING f__kdf__enb(const OCTETSTRING &kasme, const INTEGER &ul_count)
+{
+	TTCN_Buffer ttcn_buf_kasme(kasme);
+	uint8_t kenb[32];
+
+	mme_kdf_enb(ttcn_buf_kasme.get_data(), (int)ul_count, kenb);
+	return OCTETSTRING(sizeof(kenb), kenb);
+}
+
+OCTETSTRING f__kdf__nh(const OCTETSTRING &kasme, const OCTETSTRING &sync_inp)
+{
+	TTCN_Buffer ttcn_buf_kasme(kasme);
+	TTCN_Buffer ttcn_buf_sync_inp(sync_inp);
+	uint8_t kenb[32];
+
+	mme_kdf_nh(ttcn_buf_kasme.get_data(), ttcn_buf_sync_inp.get_data(), kenb);
+	return OCTETSTRING(sizeof(kenb), kenb);
+}
+
+
+
+} // namespace