From 138ec1f8e74c3b41249c1ab6c36de509bc67d8f6 Mon Sep 17 00:00:00 2001
From: Andre Puschmann <andre@softwareradiosystems.com>
Date: Fri, 10 Jul 2020 13:21:44 +0200
Subject: [PATCH] nas,usim: remove use of shadowed variables

---
 srsue/src/stack/upper/nas.cc  |  1 -
 srsue/src/stack/upper/usim.cc | 45 +++++++++++++++++------------------
 2 files changed, 22 insertions(+), 24 deletions(-)

diff --git a/srsue/src/stack/upper/nas.cc b/srsue/src/stack/upper/nas.cc
index 6c5a9f694..5ba9ccca8 100644
--- a/srsue/src/stack/upper/nas.cc
+++ b/srsue/src/stack/upper/nas.cc
@@ -809,7 +809,6 @@ void nas::integrity_generate(uint8_t* key_128,
 
 // This function depends to a valid k_nas_int.
 // This key is generated in the security mode command.
-
 bool nas::integrity_check(byte_buffer_t* pdu)
 {
   if (pdu == nullptr) {
diff --git a/srsue/src/stack/upper/usim.cc b/srsue/src/stack/upper/usim.cc
index 2785f76d4..010026313 100644
--- a/srsue/src/stack/upper/usim.cc
+++ b/srsue/src/stack/upper/usim.cc
@@ -191,35 +191,35 @@ auth_result_t usim::generate_authentication_response(uint8_t* rand,
                                                      uint16_t mnc,
                                                      uint8_t* res,
                                                      int*     res_len,
-                                                     uint8_t* k_asme)
+                                                     uint8_t* k_asme_)
 {
   if (auth_algo_xor == auth_algo) {
-    return gen_auth_res_xor(rand, autn_enb, mcc, mnc, res, res_len, k_asme);
+    return gen_auth_res_xor(rand, autn_enb, mcc, mnc, res, res_len, k_asme_);
   } else {
-    return gen_auth_res_milenage(rand, autn_enb, mcc, mnc, res, res_len, k_asme);
+    return gen_auth_res_milenage(rand, autn_enb, mcc, mnc, res, res_len, k_asme_);
   }
 }
 
-void usim::generate_nas_keys(uint8_t*                    k_asme,
+void usim::generate_nas_keys(uint8_t*                    k_asme_,
                              uint8_t*                    k_nas_enc,
                              uint8_t*                    k_nas_int,
                              CIPHERING_ALGORITHM_ID_ENUM cipher_algo,
                              INTEGRITY_ALGORITHM_ID_ENUM integ_algo)
 {
   // Generate K_nas_enc and K_nas_int
-  security_generate_k_nas(k_asme, cipher_algo, integ_algo, k_nas_enc, k_nas_int);
+  security_generate_k_nas(k_asme_, cipher_algo, integ_algo, k_nas_enc, k_nas_int);
 }
 
 /*******************************************************************************
   RRC interface
 *******************************************************************************/
 
-void usim::generate_as_keys(uint8_t* k_asme, uint32_t count_ul, srslte::as_security_config_t* sec_cfg)
+void usim::generate_as_keys(uint8_t* k_asme_, uint32_t count_ul, srslte::as_security_config_t* sec_cfg)
 {
   // Generate K_enb
-  security_generate_k_enb(k_asme, count_ul, k_enb);
+  security_generate_k_enb(k_asme_, count_ul, k_enb);
 
-  memcpy(this->k_asme, k_asme, 32);
+  memcpy(k_asme, k_asme_, 32);
 
   // Save initial k_enb
   memcpy(k_enb_initial, k_enb, 32);
@@ -348,71 +348,70 @@ auth_result_t usim::gen_auth_res_xor(uint8_t* rand,
                                      uint16_t mnc,
                                      uint8_t* res,
                                      int*     res_len,
-                                     uint8_t* k_asme)
+                                     uint8_t* k_asme_)
 {
   auth_result_t result = AUTH_OK;
-  uint32_t      i;
   uint8_t       sqn[6];
   uint8_t       xdout[16];
   uint8_t       cdout[8];
 
   // Use RAND and K to compute RES, CK, IK and AK
-  for (i = 0; i < 16; i++) {
+  for (uint32_t i = 0; i < 16; i++) {
     xdout[i] = k[i] ^ rand[i];
   }
-  for (i = 0; i < 16; i++) {
+  for (uint32_t i = 0; i < 16; i++) {
     res[i] = xdout[i];
     ck[i]  = xdout[(i + 1) % 16];
     ik[i]  = xdout[(i + 2) % 16];
   }
-  for (i = 0; i < 6; i++) {
+  for (uint32_t i = 0; i < 6; i++) {
     ak[i] = xdout[i + 3];
   }
 
   *res_len = 8;
 
   // Extract sqn from autn
-  for (i = 0; i < 6; i++) {
+  for (uint32_t i = 0; i < 6; i++) {
     sqn[i] = autn_enb[i] ^ ak[i];
   }
   // Extract AMF from autn
-  for (int i = 0; i < 2; i++) {
+  for (uint32_t i = 0; i < 2; i++) {
     amf[i] = autn_enb[6 + i];
   }
 
   // Generate cdout
-  for (i = 0; i < 6; i++) {
+  for (uint32_t i = 0; i < 6; i++) {
     cdout[i] = sqn[i];
   }
-  for (i = 0; i < 2; i++) {
+  for (uint32_t i = 0; i < 2; i++) {
     cdout[6 + i] = amf[i];
   }
 
   // Generate MAC
-  for (i = 0; i < 8; i++) {
+  for (uint32_t i = 0; i < 8; i++) {
     mac[i] = xdout[i] ^ cdout[i];
   }
 
   // Construct AUTN
-  for (i = 0; i < 6; i++) {
+  for (uint32_t i = 0; i < 6; i++) {
     autn[i] = sqn[i] ^ ak[i];
   }
-  for (i = 0; i < 2; i++) {
+  for (uint32_t i = 0; i < 2; i++) {
     autn[6 + i] = amf[i];
   }
-  for (i = 0; i < 8; i++) {
+  for (uint32_t i = 0; i < 8; i++) {
     autn[8 + i] = mac[i];
   }
 
   // Compare AUTNs
-  for (i = 0; i < 16; i++) {
+  for (uint32_t i = 0; i < 16; i++) {
     if (autn[i] != autn_enb[i]) {
       result = AUTH_FAILED;
     }
   }
 
   // Generate K_asme
-  security_generate_k_asme(ck, ik, ak, sqn, mcc, mnc, k_asme);
+  security_generate_k_asme(ck, ik, ak, sqn, mcc, mnc, k_asme_);
 
   return result;
 }