Remove remaining Linux C-style casts & fix const correctness

Many C style casts remain after 181f076 ("clang-tidy: Apply fixes
"google-readability-casting" (project-chip#3034)").

The reason they were not updated is typically because they are casting
away const qualifiers. Fix these cases or add a const_cast<> if
appropriate.

examples/shell/shell_common/cmd_device.cpp

@@ -177,7 +177,7 @@ static CHIP_ERROR ConfigGetDeviceCert(bool printHeader)
         streamer_printf(sout, "DeviceCert:      ");
     }
     // Determine the length of the device certificate.
-    error = ConfigurationMgr().GetDeviceCertificate((uint8_t *) nullptr, 0, certLen);
+    error = ConfigurationMgr().GetDeviceCertificate(nullptr, 0, certLen);
     SuccessOrExit(error);
 
     // Fail if no certificate has been configured.
@@ -213,7 +213,7 @@ static CHIP_ERROR ConfigGetDeviceCaCerts(bool printHeader)
         streamer_printf(sout, "DeviceCaCerts:   ");
     }
     // Determine the length of the device certificate.
-    error = ConfigurationMgr().GetDeviceIntermediateCACerts((uint8_t *) nullptr, 0, certLen);
+    error = ConfigurationMgr().GetDeviceIntermediateCACerts(nullptr, 0, certLen);
     SuccessOrExit(error);
 
     // Fail if no certificate has been configured.
@@ -266,7 +266,7 @@ static CHIP_ERROR ConfigGetManufacturerDeviceCert(bool printHeader)
         streamer_printf(sout, "MfrDeviceCert:   ");
     }
     // Determine the length of the device certificate.
-    error = ConfigurationMgr().GetManufacturerDeviceCertificate((uint8_t *) nullptr, 0, certLen);
+    error = ConfigurationMgr().GetManufacturerDeviceCertificate(nullptr, 0, certLen);
     SuccessOrExit(error);
 
     // Fail if no certificate has been configured.
@@ -302,7 +302,7 @@ static CHIP_ERROR ConfigGetManufacturerDeviceCaCerts(bool printHeader)
         streamer_printf(sout, "MfgDeviceCaCerts:");
     }
     // Determine the length of the device certificate.
-    error = ConfigurationMgr().GetManufacturerDeviceIntermediateCACerts((uint8_t *) nullptr, 0, certLen);
+    error = ConfigurationMgr().GetManufacturerDeviceIntermediateCACerts(nullptr, 0, certLen);
     SuccessOrExit(error);
 
     // Fail if no certificate has been configured.

src/ble/BLEEndPoint.cpp

@@ -551,7 +551,7 @@ BLE_ERROR BLEEndPoint::Init(BleLayer * bleLayer, BLE_CONNECTION_OBJECT connObj,
     //
     // Beware this line should we ever use virtuals in this class or its
     // super(s). See similar lines in chip::System::Layer end points.
-    memset((void *) this, 0, sizeof(*this));
+    memset(this, 0, sizeof(*this));
 
     // If end point plays peripheral role, expect ack for indication sent as last step of BTP handshake.
     // If central, periperal's handshake indication 'ack's write sent by central to kick off the BTP handshake.

src/ble/BtpEngine.h

@@ -92,9 +92,6 @@ class BtpEngine
 
 public:
     // Public functions:
-    BtpEngine() {}
-    ~BtpEngine() {}
-
     BLE_ERROR Init(void * an_app_state, bool expect_first_ack);
 
     inline void SetTxFragmentSize(uint8_t size) { mTxFragmentSize = size; }

src/controller/python/ChipDeviceController-BlePlatformDelegate.cpp

@@ -38,7 +38,7 @@ bool DeviceController_BlePlatformDelegate::SubscribeCharacteristic(BLE_CONNECTIO
 
     if (subscribeCB && svcId && charId)
     {
-        return subscribeCB(connObj, (void *) svcId->bytes, (void *) charId->bytes, subscribe);
+        return subscribeCB(connObj, static_cast<const void *>(svcId->bytes), static_cast<const void *>(charId->bytes), subscribe);
     }
 
     return false;
@@ -52,7 +52,7 @@ bool DeviceController_BlePlatformDelegate::UnsubscribeCharacteristic(BLE_CONNECT
 
     if (subscribeCB && svcId && charId)
     {
-        return subscribeCB(connObj, (void *) svcId->bytes, (void *) charId->bytes, !subscribe);
+        return subscribeCB(connObj, static_cast<const void *>(svcId->bytes), static_cast<const void *>(charId->bytes), !subscribe);
     }
 
     return false;
@@ -94,7 +94,8 @@ bool DeviceController_BlePlatformDelegate::SendWriteRequest(BLE_CONNECTION_OBJEC
 
     if (writeCB && svcId && charId && pBuf)
     {
-        ret = writeCB(connObj, (void *) svcId->bytes, (void *) charId->bytes, (void *) pBuf->Start(), pBuf->DataLength());
+        ret = writeCB(connObj, static_cast<const void *>(svcId->bytes), static_cast<const void *>(charId->bytes),
+                      static_cast<void *>(pBuf->Start()), pBuf->DataLength());
     }
 
     // Release delegate's reference to pBuf. pBuf will be freed when both platform delegate and Chip stack free their references to

src/controller/python/ChipDeviceController-BlePlatformDelegate.h

@@ -23,8 +23,9 @@
 #include <ble/BleLayer.h>
 #include <ble/BlePlatformDelegate.h>
 
-typedef bool (*WriteBleCharacteristicCBFunct)(void * connObj, void * svcId, void * charId, void * buffer, uint16_t length);
-typedef bool (*SubscribeBleCharacteristicCBFunct)(void * connObj, void * svcId, void * charId, bool subscribe);
+typedef bool (*WriteBleCharacteristicCBFunct)(void * connObj, const void * svcId, const void * charId, const void * buffer,
+                                              uint16_t length);
+typedef bool (*SubscribeBleCharacteristicCBFunct)(void * connObj, const void * svcId, const void * charId, bool subscribe);
 typedef bool (*CloseBleCBFunct)(void * connObj);
 
 class DeviceController_BlePlatformDelegate : public chip::Ble::BlePlatformDelegate

src/crypto/CHIPCryptoPAL.h

@@ -108,7 +108,8 @@ class ECPKey
 public:
     virtual SupportedECPKeyTypes Type() const = 0;
     virtual size_t Length() const             = 0;
-    virtual operator uint8_t *() const        = 0;
+    virtual operator const uint8_t *() const  = 0;
+    virtual operator uint8_t *()              = 0;
 
     virtual CHIP_ERROR ECDSA_validate_msg_signature(const uint8_t * msg, const size_t msg_length, const Sig & signature) const
     {
@@ -143,7 +144,8 @@ class CapacityBoundBuffer
 
     /** @brief Returns buffer pointer
      **/
-    operator uint8_t *() const { return (uint8_t *) bytes; }
+    operator uint8_t *() { return bytes; }
+    operator const uint8_t *() const { return bytes; }
 
 private:
     uint8_t bytes[Cap];
@@ -159,7 +161,8 @@ class P256PublicKey : public ECPKey<P256ECDSASignature>
 public:
     SupportedECPKeyTypes Type() const override { return SupportedECPKeyTypes::ECP256R1; }
     size_t Length() const override { return kP256_PublicKey_Length; }
-    operator uint8_t *() const override { return (uint8_t *) bytes; }
+    operator uint8_t *() override { return bytes; }
+    operator const uint8_t *() const override { return bytes; }
 
     CHIP_ERROR ECDSA_validate_msg_signature(const uint8_t * msg, const size_t msg_length,
                                             const P256ECDSASignature & signature) const override;

src/crypto/CHIPCryptoPALOpenSSL.cpp

@@ -239,7 +239,8 @@ CHIP_ERROR AES_CCM_decrypt(const uint8_t * ciphertext, size_t ciphertext_length,
 
     // Pass in expected tag
     VerifyOrExit(CanCastTo<int>(tag_length), error = CHIP_ERROR_INVALID_ARGUMENT);
-    result = EVP_CIPHER_CTX_ctrl(context, EVP_CTRL_CCM_SET_TAG, static_cast<int>(tag_length), (void *) tag);
+    result = EVP_CIPHER_CTX_ctrl(context, EVP_CTRL_CCM_SET_TAG, static_cast<int>(tag_length),
+                                 const_cast<void *>(reinterpret_cast<const void *>(tag)));
     VerifyOrExit(result == 1, error = CHIP_ERROR_INTERNAL);
 
     // Pass in key + iv
@@ -902,7 +903,7 @@ CHIP_ERROR P256Keypair::Deserialize(P256SerializedKeypair & input)
     const uint8_t * privkey = Uint8::to_const_uchar(input) + mPublicKey.Length();
 
     VerifyOrExit(input.Length() == mPublicKey.Length() + kP256_PrivateKey_Length, error = CHIP_ERROR_INVALID_ARGUMENT);
-    bbuf.Put((const uint8_t *) input, mPublicKey.Length());
+    bbuf.Put(input, mPublicKey.Length());
     VerifyOrExit(bbuf.Fit(), error = CHIP_ERROR_NO_MEMORY);
 
     nid = _nidForCurve(curve);
@@ -1062,7 +1063,7 @@ CHIP_ERROR P256Keypair::NewCertificateSigningRequest(uint8_t * out_csr, size_t &
     {                                                                                                                              \
         if (_point_ != nullptr)                                                                                                    \
         {                                                                                                                          \
-            EC_POINT_clear_free((EC_POINT *) _point_);                                                                             \
+            EC_POINT_clear_free(static_cast<EC_POINT *>(_point_));                                                                 \
         }                                                                                                                          \
     } while (0)
 
@@ -1071,7 +1072,7 @@ CHIP_ERROR P256Keypair::NewCertificateSigningRequest(uint8_t * out_csr, size_t &
     {                                                                                                                              \
         if (_bn_ != nullptr)                                                                                                       \
         {                                                                                                                          \
-            BN_clear_free((BIGNUM *) _bn_);                                                                                        \
+            BN_clear_free(static_cast<BIGNUM *>(_bn_));                                                                            \
         }                                                                                                                          \
     } while (0)
 
@@ -1102,7 +1103,7 @@ CHIP_ERROR Spake2p_P256_SHA256_HKDF_HMAC::InitInternal()
     context->curve = EC_GROUP_new_by_curve_name(NID_X9_62_prime256v1);
     VerifyOrExit(context->curve != nullptr, error = CHIP_ERROR_INTERNAL);
 
-    G = (void *) EC_GROUP_get0_generator(context->curve);
+    G = const_cast<void *>(reinterpret_cast<const void *>(EC_GROUP_get0_generator(context->curve)));
     VerifyOrExit(G != nullptr, error = CHIP_ERROR_INTERNAL);
 
     context->bn_ctx = BN_CTX_secure_new();
@@ -1229,7 +1230,7 @@ CHIP_ERROR Spake2p_P256_SHA256_HKDF_HMAC::FEWrite(const void * fe, uint8_t * out
     CHIP_ERROR error = CHIP_ERROR_INTERNAL;
     int bn_out_len;
     VerifyOrExit(CanCastTo<int>(out_len), error = CHIP_ERROR_INTERNAL);
-    bn_out_len = BN_bn2binpad((BIGNUM *) fe, Uint8::to_uchar(out), static_cast<int>(out_len));
+    bn_out_len = BN_bn2binpad(static_cast<const BIGNUM *>(fe), Uint8::to_uchar(out), static_cast<int>(out_len));
 
     VerifyOrExit(bn_out_len == static_cast<int>(out_len), error = CHIP_ERROR_INTERNAL);
 
@@ -1258,8 +1259,8 @@ CHIP_ERROR Spake2p_P256_SHA256_HKDF_HMAC::FEMul(void * fer, const void * fe1, co
 
     Spake2p_Context * context = to_inner_spake2p_context(&mSpake2pContext);
 
-    error_openssl =
-        BN_mod_mul(static_cast<BIGNUM *>(fer), (BIGNUM *) fe1, (BIGNUM *) fe2, static_cast<BIGNUM *>(order), context->bn_ctx);
+    error_openssl = BN_mod_mul(static_cast<BIGNUM *>(fer), static_cast<const BIGNUM *>(fe1), static_cast<const BIGNUM *>(fe2),
+                               static_cast<BIGNUM *>(order), context->bn_ctx);
     VerifyOrExit(error_openssl == 1, error = CHIP_ERROR_INTERNAL);
 
     error = CHIP_NO_ERROR;
@@ -1288,8 +1289,8 @@ CHIP_ERROR Spake2p_P256_SHA256_HKDF_HMAC::PointWrite(const void * R, uint8_t * o
     CHIP_ERROR error          = CHIP_ERROR_INTERNAL;
     Spake2p_Context * context = to_inner_spake2p_context(&mSpake2pContext);
 
-    size_t ec_out_len = EC_POINT_point2oct(context->curve, (EC_POINT *) R, POINT_CONVERSION_UNCOMPRESSED, Uint8::to_uchar(out),
-                                           out_len, context->bn_ctx);
+    size_t ec_out_len = EC_POINT_point2oct(context->curve, static_cast<const EC_POINT *>(R), POINT_CONVERSION_UNCOMPRESSED,
+                                           Uint8::to_uchar(out), out_len, context->bn_ctx);
     VerifyOrExit(ec_out_len == out_len, error = CHIP_ERROR_INTERNAL);
 
     error = CHIP_NO_ERROR;
@@ -1304,8 +1305,8 @@ CHIP_ERROR Spake2p_P256_SHA256_HKDF_HMAC::PointMul(void * R, const void * P1, co
 
     Spake2p_Context * context = to_inner_spake2p_context(&mSpake2pContext);
 
-    error_openssl =
-        EC_POINT_mul(context->curve, static_cast<EC_POINT *>(R), nullptr, (EC_POINT *) P1, (BIGNUM *) fe1, context->bn_ctx);
+    error_openssl = EC_POINT_mul(context->curve, static_cast<EC_POINT *>(R), nullptr, static_cast<const EC_POINT *>(P1),
+                                 static_cast<const BIGNUM *>(fe1), context->bn_ctx);
     VerifyOrExit(error_openssl == 1, error = CHIP_ERROR_INTERNAL);
 
     error = CHIP_NO_ERROR;
@@ -1331,8 +1332,8 @@ CHIP_ERROR Spake2p_P256_SHA256_HKDF_HMAC::PointAddMul(void * R, const void * P1,
     error = PointMul(R, P2, fe2);
     VerifyOrExit(error == CHIP_NO_ERROR, error = CHIP_ERROR_INTERNAL);
 
-    error_openssl = EC_POINT_add(context->curve, static_cast<EC_POINT *>(R), static_cast<EC_POINT *>(R), (const EC_POINT *) scratch,
-                                 context->bn_ctx);
+    error_openssl = EC_POINT_add(context->curve, static_cast<EC_POINT *>(R), static_cast<EC_POINT *>(R),
+                                 static_cast<const EC_POINT *>(scratch), context->bn_ctx);
     VerifyOrExit(error_openssl == 1, error = CHIP_ERROR_INTERNAL);
 
     error = CHIP_NO_ERROR;

src/include/platform/internal/BLEManager.h

@@ -65,7 +65,7 @@ class BLEManager
     CHIP_ERROR SetDeviceName(const char * deviceName);
     uint16_t NumConnections();
     void OnPlatformEvent(const ChipDeviceEvent * event);
-    chip::Ble::BleLayer * GetBleLayer() const;
+    chip::Ble::BleLayer * GetBleLayer();
 
 protected:
     // Construction/destruction limited to subclasses.
@@ -171,9 +171,9 @@ inline void BLEManager::OnPlatformEvent(const ChipDeviceEvent * event)
     return static_cast<ImplClass *>(this)->_OnPlatformEvent(event);
 }
 
-inline chip::Ble::BleLayer * BLEManager::GetBleLayer() const
+inline chip::Ble::BleLayer * BLEManager::GetBleLayer()
 {
-    return static_cast<const ImplClass *>(this)->_GetBleLayer();
+    return static_cast<ImplClass *>(this)->_GetBleLayer();
 }
 
 } // namespace Internal

src/inet/IPAddress-StringFuncts.cpp

@@ -69,12 +69,13 @@ char * IPAddress::ToString(char * buf, uint32_t bufSize) const
 #if INET_CONFIG_ENABLE_IPV4
     if (IsIPv4())
     {
-        buf = const_cast<char *>(inet_ntop(AF_INET, (const void *) &Addr[3], buf, static_cast<socklen_t>(bufSize)));
+        buf =
+            const_cast<char *>(inet_ntop(AF_INET, reinterpret_cast<const void *>(&Addr[3]), buf, static_cast<socklen_t>(bufSize)));
     }
     else
 #endif // INET_CONFIG_ENABLE_IPV4
     {
-        buf = const_cast<char *>(inet_ntop(AF_INET6, (const void *) Addr, buf, static_cast<socklen_t>(bufSize)));
+        buf = const_cast<char *>(inet_ntop(AF_INET6, reinterpret_cast<const void *>(Addr), buf, static_cast<socklen_t>(bufSize)));
     }
 #endif // !CHIP_SYSTEM_CONFIG_USE_LWIP
 

src/inet/IPAddress.cpp

@@ -149,7 +149,7 @@ lwip_ip_addr_type IPAddress::ToLwIPAddrType(IPAddressType typ)
 #if INET_CONFIG_ENABLE_IPV4
 ip4_addr_t IPAddress::ToIPv4() const
 {
-    return *(ip4_addr_t *) &Addr[3];
+    return *reinterpret_cast<ip4_addr_t *>(&Addr[3]);
 }
 
 IPAddress IPAddress::FromIPv4(const ip4_addr_t & ipv4Addr)
@@ -203,7 +203,10 @@ IPAddress IPAddress::FromIPv4(const struct in_addr & ipv4Addr)
 
 struct in6_addr IPAddress::ToIPv6() const
 {
-    return *(struct in6_addr *) &Addr;
+    in6_addr addr;
+    static_assert(sizeof(addr) == sizeof(Addr), "in6_addr size mismatch");
+    memcpy(&addr, Addr, sizeof(addr));
+    return addr;
 }
 
 IPAddress IPAddress::FromIPv6(const struct in6_addr & ipv6Addr)
@@ -225,10 +228,10 @@ IPAddress IPAddress::FromSockAddr(const struct sockaddr & sockaddr)
 {
 #if INET_CONFIG_ENABLE_IPV4
     if (sockaddr.sa_family == AF_INET)
-        return FromIPv4(((sockaddr_in *) &sockaddr)->sin_addr);
+        return FromIPv4(reinterpret_cast<const sockaddr_in *>(&sockaddr)->sin_addr);
 #endif // INET_CONFIG_ENABLE_IPV4
     if (sockaddr.sa_family == AF_INET6)
-        return FromIPv6(((sockaddr_in6 *) &sockaddr)->sin6_addr);
+        return FromIPv6(reinterpret_cast<const sockaddr_in6 *>(&sockaddr)->sin6_addr);
     return Any;
 }
 

src/inet/IPEndPointBasis.cpp

@@ -969,11 +969,11 @@ INET_ERROR IPEndPointBasis::GetSocket(IPAddressType aAddressType, int aType, int
         // logic up to check for implementations of these options and
         // to provide appropriate HAVE_xxxxx definitions accordingly.
 
-        res = setsockopt(mSocket, SOL_SOCKET, SO_REUSEADDR, (void *) &one, sizeof(one));
+        res = setsockopt(mSocket, SOL_SOCKET, SO_REUSEADDR, reinterpret_cast<const void *>(&one), sizeof(one));
         static_cast<void>(res);
 
 #ifdef SO_REUSEPORT
-        res = setsockopt(mSocket, SOL_SOCKET, SO_REUSEPORT, (void *) &one, sizeof(one));
+        res = setsockopt(mSocket, SOL_SOCKET, SO_REUSEPORT, reinterpret_cast<const void *>(&one), sizeof(one));
         if (res != 0)
         {
             ChipLogError(Inet, "SO_REUSEPORT failed: %d", errno);
@@ -987,7 +987,7 @@ INET_ERROR IPEndPointBasis::GetSocket(IPAddressType aAddressType, int aType, int
 #ifdef IPV6_V6ONLY
         if (aAddressType == kIPAddressType_IPv6)
         {
-            res = setsockopt(mSocket, IPPROTO_IPV6, IPV6_V6ONLY, (void *) &one, sizeof(one));
+            res = setsockopt(mSocket, IPPROTO_IPV6, IPV6_V6ONLY, reinterpret_cast<const void *>(&one), sizeof(one));
             if (res != 0)
             {
                 ChipLogError(Inet, "IPV6_V6ONLY failed: %d", errno);
@@ -999,7 +999,7 @@ INET_ERROR IPEndPointBasis::GetSocket(IPAddressType aAddressType, int aType, int
 #ifdef IP_PKTINFO
         if (aAddressType == kIPAddressType_IPv4)
         {
-            res = setsockopt(mSocket, IPPROTO_IP, IP_PKTINFO, (void *) &one, sizeof(one));
+            res = setsockopt(mSocket, IPPROTO_IP, IP_PKTINFO, reinterpret_cast<const void *>(&one), sizeof(one));
             if (res != 0)
             {
                 ChipLogError(Inet, "IP_PKTINFO failed: %d", errno);
@@ -1011,7 +1011,7 @@ INET_ERROR IPEndPointBasis::GetSocket(IPAddressType aAddressType, int aType, int
 #ifdef IPV6_RECVPKTINFO
         if (aAddressType == kIPAddressType_IPv6)
         {
-            res = setsockopt(mSocket, IPPROTO_IPV6, IPV6_RECVPKTINFO, (void *) &one, sizeof(one));
+            res = setsockopt(mSocket, IPPROTO_IPV6, IPV6_RECVPKTINFO, reinterpret_cast<const void *>(&one), sizeof(one));
             if (res != 0)
             {
                 ChipLogError(Inet, "IPV6_PKTINFO failed: %d", errno);

src/inet/TCPEndPoint.cpp

@@ -413,7 +413,7 @@ INET_ERROR TCPEndPoint::Connect(IPAddress addr, uint16_t port, InterfaceId intfI
             // If the permission is denied(EACCES) because CHIP is running in a context
             // that does not have privileged access, choose a source address on the
             // interface to bind the connetion to.
-            int r = setsockopt(mSocket, SOL_SOCKET, SO_BINDTODEVICE, (void *) &ifr, sizeof(ifr));
+            int r = setsockopt(mSocket, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr));
             if (r < 0 && errno != EACCES)
             {
                 return res = chip::System::MapErrorPOSIX(errno);
@@ -2227,7 +2227,7 @@ INET_ERROR TCPEndPoint::GetSocket(IPAddressType addrType)
         if (family == PF_INET6)
         {
             int one = 1;
-            setsockopt(mSocket, IPPROTO_IPV6, IPV6_V6ONLY, (void *) &one, sizeof(one));
+            setsockopt(mSocket, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one));
         }
 #endif // defined(IPV6_V6ONLY)
 

src/inet/tests/TestInetAddress.cpp

@@ -1234,22 +1234,22 @@ void CheckFromSocket(nlTestSuite * inSuite, void * inContext)
             memset(&sock_v4, 0, sizeof(struct sockaddr_in));
             sock_v4.sin_family = AF_INET;
             memcpy(&sock_v4.sin_addr.s_addr, &addr[3], sizeof(struct in_addr));
-            test_addr_2 = IPAddress::FromSockAddr((struct sockaddr &) sock_v4);
+            test_addr_2 = IPAddress::FromSockAddr(reinterpret_cast<struct sockaddr &>(sock_v4));
             break;
 #endif // INET_CONFIG_ENABLE_IPV4
 
         case kIPAddressType_IPv6:
             memset(&sock_v6, 0, sizeof(struct sockaddr_in6));
             sock_v6.sin6_family = AF_INET6;
             memcpy(&sock_v6.sin6_addr.s6_addr, addr, sizeof(struct in6_addr));
-            test_addr_2 = IPAddress::FromSockAddr((struct sockaddr &) sock_v6);
+            test_addr_2 = IPAddress::FromSockAddr(reinterpret_cast<struct sockaddr &>(sock_v6));
             break;
 
         case kIPAddressType_Any:
             memset(&sock_v6, 0, sizeof(struct sockaddr_in6));
             sock_v6.sin6_family = 0;
             memcpy(&sock_v6.sin6_addr.s6_addr, addr, sizeof(struct in6_addr));
-            test_addr_2 = IPAddress::FromSockAddr((struct sockaddr &) sock_v6);
+            test_addr_2 = IPAddress::FromSockAddr(reinterpret_cast<struct sockaddr &>(sock_v6));
             break;
 
         default: