1e41f4b71Sopenharmony_ci# crypto_digest.h 2e41f4b71Sopenharmony_ci 3e41f4b71Sopenharmony_ci 4e41f4b71Sopenharmony_ci## Overview 5e41f4b71Sopenharmony_ci 6e41f4b71Sopenharmony_ciProvides APIs for message digest (MD) algorithms. 7e41f4b71Sopenharmony_ci 8e41f4b71Sopenharmony_ci**Library**: libohcrypto.z.so 9e41f4b71Sopenharmony_ci 10e41f4b71Sopenharmony_ci**System capability**: SystemCapability.Security.CryptoFramework 11e41f4b71Sopenharmony_ci 12e41f4b71Sopenharmony_ci**Since**: 12 13e41f4b71Sopenharmony_ci 14e41f4b71Sopenharmony_ci**Related module**: [CryptoDigestApi](_crypto_digest_api.md) 15e41f4b71Sopenharmony_ci 16e41f4b71Sopenharmony_ci 17e41f4b71Sopenharmony_ci## Summary 18e41f4b71Sopenharmony_ci 19e41f4b71Sopenharmony_ci 20e41f4b71Sopenharmony_ci### Types 21e41f4b71Sopenharmony_ci 22e41f4b71Sopenharmony_ci| Name | Description | 23e41f4b71Sopenharmony_ci| -------- | -------- | 24e41f4b71Sopenharmony_ci| typedef struct [OH_CryptoDigest](_crypto_digest_api.md#oh_cryptodigest) [OH_CryptoDigest](_crypto_digest_api.md#oh_cryptodigest) | Defines an MD. | 25e41f4b71Sopenharmony_ci 26e41f4b71Sopenharmony_ci 27e41f4b71Sopenharmony_ci### Functions 28e41f4b71Sopenharmony_ci 29e41f4b71Sopenharmony_ci| Name | Description | 30e41f4b71Sopenharmony_ci| -------- | -------- | 31e41f4b71Sopenharmony_ci| [OH_Crypto_ErrCode](_crypto_common_api.md#oh_crypto_errcode) [OH_CryptoDigest_Create](_crypto_digest_api.md#oh_cryptodigest_create) (const char \*algoName, [OH_CryptoDigest](_crypto_digest_api.md#oh_cryptodigest) \*\*ctx) | Creates an MD instance based on the given algorithm name. | 32e41f4b71Sopenharmony_ci| [OH_Crypto_ErrCode](_crypto_common_api.md#oh_crypto_errcode) [OH_CryptoDigest_Update](_crypto_digest_api.md#oh_cryptodigest_update) ([OH_CryptoDigest](_crypto_digest_api.md#oh_cryptodigest) \*ctx, [Crypto_DataBlob](_crypto___data_blob.md) \*in) | Updates the data used for generating an MD. | 33e41f4b71Sopenharmony_ci| [OH_Crypto_ErrCode](_crypto_common_api.md#oh_crypto_errcode) [OH_CryptoDigest_Final](_crypto_digest_api.md#oh_cryptodigest_final) ([OH_CryptoDigest](_crypto_digest_api.md#oh_cryptodigest) \*ctx, [Crypto_DataBlob](_crypto___data_blob.md) \*out) | Generates an MD. | 34e41f4b71Sopenharmony_ci| uint32_t [OH_CryptoDigest_GetLength](_crypto_digest_api.md#oh_cryptodigest_getlength) ([OH_CryptoDigest](_crypto_digest_api.md#oh_cryptodigest) \*ctx) | Obtains the length of an MD. | 35e41f4b71Sopenharmony_ci| const char \* [OH_CryptoDigest_GetAlgoName](_crypto_digest_api.md#oh_cryptodigest_getalgoname) ([OH_CryptoDigest](_crypto_digest_api.md#oh_cryptodigest) \*ctx) | Obtains the digest algorithm. | 36e41f4b71Sopenharmony_ci| void [OH_DigestCrypto_Destroy](_crypto_digest_api.md#oh_digestcrypto_destroy) ([OH_CryptoDigest](_crypto_digest_api.md#oh_cryptodigest) \*ctx) | Destroys an MD instance. | 37