+/**
+* Delete client callback info all.
+*/
+void OCClearCallBackList();
+
+/**
+ * Delete observer info all.
+ */
+void OCClearObserverlist();
+
+/**
+ * API to encrypt the un-encrypted DB file before OCRegisterPersistentStorageHandler
+ * If the API is successful, un-encrypted file will be removed, and if the encrypted file
+ * is currupted, then it restores encrypted file using rescue file.
+ *
+ * @param[in] key key used for encryption
+ * @param[in] psPlain OCPersistentStorage for the plain DB
+ * @param[in] psEnc OCPersistentStorage for the encrypted DB
+ * @param[in] psRescue OCPersistentStorage for the rescue DB
+ *
+ * @return ::OC_STACK_OK on success and other value otherwise.
+ */
+OCStackResult OCSetSecurePSI(const unsigned char *key, const OCPersistentStorage *psPlain,
+ const OCPersistentStorage *psEnc, const OCPersistentStorage *psRescue);
+
+/**
+ * Generic Encryption function to encrypt data buffer in pt
+ * and update in ct and len in ct_len. (AES-CBC-HMAC)
+ *
+ * @param[in] pt plaintext to be encrypted
+ * @param[in] pt_len length of plaintext
+ * @param[out] ct ciphered text
+ * @param[out] ct_len is length of the ciphered text.
+ *
+ * @return ::0 for Success.
+ */
+int OCEncrypt(const unsigned char *pt, size_t pt_len,
+ unsigned char **ct, size_t *ct_len);
+
+/**
+ * Generic Decryption fucntion to decrypt data buffer in ct
+ * and update in pt and len in pt_len. (AES-CBC-HMAC)
+ *
+ * @param[in] ct ciphered to be decrypted
+ * @param[in] ct_len length of cipher text
+ * @param[out] pt plaintext text
+ * @param[out] pt_len is length of the palintext text.
+ *
+ * @return ::0 for Success.
+ */
+int OCDecrypt(const unsigned char *ct, size_t ct_len,
+ unsigned char **pt, size_t *pt_len);
+
+/**
+ * API to set key to psi
+ *
+ * @param[in] key key used for encryption
+ * @return ::OC_STACK_OK for Success, otherwise some error value.
+ */
+OCStackResult OCSetKey(const unsigned char* key);
+
+/**
+ * API to get key from psi
+ *
+ * @param[out] key key used for encryption
+ * @return ::OC_STACK_OK for Success, otherwise some error value.
+ */
+OCStackResult OCGetKey(unsigned char* key);
+
+/**
+ * API to register OTM event handler
+ *
+ * @param[in] ctx user context returned in the callback
+ * @param[in] cb callback function to receive the OTM event on server side
+ * @return ::OC_STACK_OK for Success, otherwise some error value.
+ */
+OCStackResult OCSetOtmEventHandler(void *ctx, OCOtmEventHandler cb);
+