From 615bf36d889db60f249ed0233ca7b98e31af7c1b Mon Sep 17 00:00:00 2001
From: Abtin Keshavarzian <abtink@google.com>
Date: Wed, 27 May 2020 22:27:55 -0700
Subject: [PATCH] [crypto] update method documentation and style (#5015)

---
 src/core/crypto/aes_ecb.cpp     | 4 ++--
 src/core/crypto/aes_ecb.hpp     | 6 +++---
 src/core/crypto/ecdsa.hpp       | 1 +
 src/core/crypto/hmac_sha256.cpp | 4 ++--
 src/core/crypto/hmac_sha256.hpp | 4 ++--
 src/core/crypto/mbedtls.cpp     | 6 +++---
 src/core/crypto/mbedtls.hpp     | 9 +++++++--
 src/core/crypto/sha256.cpp      | 4 ++--
 src/core/crypto/sha256.hpp      | 4 ++--
 9 files changed, 24 insertions(+), 18 deletions(-)

diff --git a/src/core/crypto/aes_ecb.cpp b/src/core/crypto/aes_ecb.cpp
index 2c252a05f..77fea9030 100644
--- a/src/core/crypto/aes_ecb.cpp
+++ b/src/core/crypto/aes_ecb.cpp
@@ -36,7 +36,7 @@
 namespace ot {
 namespace Crypto {
 
-AesEcb::AesEcb()
+AesEcb::AesEcb(void)
 {
     mbedtls_aes_init(&mContext);
 }
@@ -51,7 +51,7 @@ void AesEcb::Encrypt(const uint8_t aInput[kBlockSize], uint8_t aOutput[kBlockSiz
     mbedtls_aes_crypt_ecb(&mContext, MBEDTLS_AES_ENCRYPT, aInput, aOutput);
 }
 
-AesEcb::~AesEcb()
+AesEcb::~AesEcb(void)
 {
     mbedtls_aes_free(&mContext);
 }
diff --git a/src/core/crypto/aes_ecb.hpp b/src/core/crypto/aes_ecb.hpp
index 1d86eccd0..085ccfa50 100644
--- a/src/core/crypto/aes_ecb.hpp
+++ b/src/core/crypto/aes_ecb.hpp
@@ -64,19 +64,19 @@ public:
      * Constructor to initialize the mbedtls_aes_context.
      *
      */
-    AesEcb();
+    AesEcb(void);
 
     /**
      * Destructor to free the mbedtls_aes_context.
      *
      */
-    ~AesEcb();
+    ~AesEcb(void);
 
     /**
      * This method sets the key.
      *
      * @param[in]  aKey        A pointer to the key.
-     * @param[in]  aKeyLength  The key length in bytes.
+     * @param[in]  aKeyLength  The key length in bits.
      *
      */
     void SetKey(const uint8_t *aKey, uint16_t aKeyLength);
diff --git a/src/core/crypto/ecdsa.hpp b/src/core/crypto/ecdsa.hpp
index 0c169ab2c..2248ecaac 100644
--- a/src/core/crypto/ecdsa.hpp
+++ b/src/core/crypto/ecdsa.hpp
@@ -72,6 +72,7 @@ public:
      * @retval  OT_ERROR_NO_BUFS      Output buffer is too small.
      * @retval  OT_ERROR_INVALID_ARGS Private key is not valid EC Private Key.
      * @retval  OT_ERROR_FAILED       Error during signing.
+     *
      */
     static otError Sign(uint8_t *      aOutput,
                         uint16_t *     aOutputLength,
diff --git a/src/core/crypto/hmac_sha256.cpp b/src/core/crypto/hmac_sha256.cpp
index 17358b548..2d981c9d9 100644
--- a/src/core/crypto/hmac_sha256.cpp
+++ b/src/core/crypto/hmac_sha256.cpp
@@ -36,7 +36,7 @@
 namespace ot {
 namespace Crypto {
 
-HmacSha256::HmacSha256()
+HmacSha256::HmacSha256(void)
 {
     const mbedtls_md_info_t *mdInfo = NULL;
     mbedtls_md_init(&mContext);
@@ -44,7 +44,7 @@ HmacSha256::HmacSha256()
     mbedtls_md_setup(&mContext, mdInfo, 1);
 }
 
-HmacSha256::~HmacSha256()
+HmacSha256::~HmacSha256(void)
 {
     mbedtls_md_free(&mContext);
 }
diff --git a/src/core/crypto/hmac_sha256.hpp b/src/core/crypto/hmac_sha256.hpp
index fe28d3f2f..ed3a84471 100644
--- a/src/core/crypto/hmac_sha256.hpp
+++ b/src/core/crypto/hmac_sha256.hpp
@@ -66,13 +66,13 @@ public:
      * Constructor for initialization of mbedtls_md_context_t.
      *
      */
-    HmacSha256();
+    HmacSha256(void);
 
     /**
      * Destructor for freeing of mbedtls_md_context_t.
      *
      */
-    ~HmacSha256();
+    ~HmacSha256(void);
 
     /**
      * This method sets the key.
diff --git a/src/core/crypto/mbedtls.cpp b/src/core/crypto/mbedtls.cpp
index 827c3602a..58b183c4e 100644
--- a/src/core/crypto/mbedtls.cpp
+++ b/src/core/crypto/mbedtls.cpp
@@ -74,11 +74,11 @@ MbedTls::MbedTls(void)
 #endif // !OPENTHREAD_CONFIG_MULTIPLE_INSTANCE_ENABLE && OPENTHREAD_CONFIG_ENABLE_BUILTIN_MBEDTLS_MANAGEMENT
 }
 
-otError MbedTls::MapError(int rval)
+otError MbedTls::MapError(int aMbedTlsError)
 {
     otError error = OT_ERROR_NONE;
 
-    switch (rval)
+    switch (aMbedTlsError)
     {
 #ifdef MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED
     case MBEDTLS_ERR_PK_TYPE_MISMATCH:
@@ -154,7 +154,7 @@ otError MbedTls::MapError(int rval)
         break;
 
     default:
-        OT_ASSERT(rval >= 0);
+        OT_ASSERT(aMbedTlsError >= 0);
         break;
     }
 
diff --git a/src/core/crypto/mbedtls.hpp b/src/core/crypto/mbedtls.hpp
index 697e7b96c..b2df719c2 100644
--- a/src/core/crypto/mbedtls.hpp
+++ b/src/core/crypto/mbedtls.hpp
@@ -64,9 +64,14 @@ public:
     MbedTls(void);
 
     /**
-     * This method converts from MbedTls error to OpenThread error.
+     * This method converts an mbed TLS error to OpenThread error.
+     *
+     * @param[in] aMbedTlsError  The mbed TLS error.
+     *
+     * @returns The mapped otError.
+     *
      */
-    static otError MapError(int rval);
+    static otError MapError(int aMbedTlsError);
 };
 
 /**
diff --git a/src/core/crypto/sha256.cpp b/src/core/crypto/sha256.cpp
index 6ca028ef7..5715192c7 100644
--- a/src/core/crypto/sha256.cpp
+++ b/src/core/crypto/sha256.cpp
@@ -36,12 +36,12 @@
 namespace ot {
 namespace Crypto {
 
-Sha256::Sha256()
+Sha256::Sha256(void)
 {
     mbedtls_sha256_init(&mContext);
 }
 
-Sha256::~Sha256()
+Sha256::~Sha256(void)
 {
     mbedtls_sha256_free(&mContext);
 }
diff --git a/src/core/crypto/sha256.hpp b/src/core/crypto/sha256.hpp
index a5efedaff..ab7ed6818 100644
--- a/src/core/crypto/sha256.hpp
+++ b/src/core/crypto/sha256.hpp
@@ -66,13 +66,13 @@ public:
      * Constructor for initializing mbedtls_sha256_context.
      *
      */
-    Sha256();
+    Sha256(void);
 
     /**
      * Destructor for freeing mbedtls_sha256_context.
      *
      */
-    ~Sha256();
+    ~Sha256(void);
 
     /**
      * This method starts the SHA-256 computation.