Cryptoki: a cryptographic Token Interface
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pkcs11-base-v2.40-cos01
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- C_DigestEncryptUpdate
- C_DigestInit and C_EncryptInit
C_DigestEncryptUpdateCK_DEFINE_FUNCTION(CK_RV, C_DigestEncryptUpdate)( CK_SESSION_HANDLE hSession, CK_BYTE_PTR pPart, CK_ULONG ulPartLen, CK_BYTE_PTR pEncryptedPart, CK_ULONG_PTR pulEncryptedPartLen ); C_DigestEncryptUpdate continues multiple-part digest and encryption operations, processing another data part. hSession is the session’s handle; pPart points to the data part; ulPartLen is the length of the data part; pEncryptedPart points to the location that receives the digested and encrypted data part; pulEncryptedPartLen points to the location that holds the length of the encrypted data part. C_DigestEncryptUpdate uses the convention described in Section on producing output. If a C_DigestEncryptUpdate call does not produce encrypted output (because an error occurs, or because pEncryptedPart has the value NULL_PTR, or because pulEncryptedPartLen is too small to hold the entire encrypted part output), then no plaintext is passed to the active digest operation. Digest and encryption operations must both be active (they must have been initialized with C_DigestInit and C_EncryptInit, respectively). This function may be called any number of times in succession, and may be interspersed with C_DigestUpdate, C_DigestKey, and C_EncryptUpdate calls (it would be somewhat unusual to intersperse calls to C_DigestEncryptUpdate with calls to C_DigestKey, however). Return values: CKR_BUFFER_TOO_SMALL, CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DATA_LEN_RANGE, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_CANCELED, CKR_FUNCTION_FAILED, CKR_GENERAL_ERROR, CKR_HOST_MEMORY, CKR_OK, CKR_OPERATION_NOT_INITIALIZED, CKR_SESSION_CLOSED, CKR_SESSION_HANDLE_INVALID. Example: #define BUF_SZ 512 CK_SESSION_HANDLE hSession; CK_OBJECT_HANDLE hKey; CK_BYTE iv[8]; CK_MECHANISM digestMechanism = { CKM_MD5, NULL_PTR, 0 }; CK_MECHANISM encryptionMechanism = { CKM_DES_ECB, iv, sizeof(iv) }; CK_BYTE encryptedData[BUF_SZ]; CK_ULONG ulEncryptedDataLen; CK_BYTE digest[16]; CK_ULONG ulDigestLen; CK_BYTE data[(2*BUF_SZ)+8]; CK_RV rv; int i; .
memset(iv, 0, sizeof(iv)); memset(data, ‘A’, ((2*BUF_SZ)+5)); rv = C_EncryptInit(hSession, &encryptionMechanism, hKey); if (rv != CKR_OK) { . . . } rv = C_DigestInit(hSession, &digestMechanism); if (rv != CKR_OK) { . . . } ulEncryptedDataLen = sizeof(encryptedData); rv = C_DigestEncryptUpdate( hSession, &data[0], BUF_SZ, encryptedData, &ulEncryptedDataLen); . . . ulEncryptedDataLen = sizeof(encryptedData); rv = C_DigestEncryptUpdate( hSession, &data[BUF_SZ], BUF_SZ, encryptedData, &ulEncryptedDataLen); . . . /*
* separate calls to deal with padding issues in ECB mode */ /* First, complete the digest on the buffer */ rv = C_DigestUpdate(hSession, &data[BUF_SZ*2], 5); . . . ulDigestLen = sizeof(digest); rv = C_DigestFinal(hSession, digest, &ulDigestLen); . . . /* Then, pad last part with 3 0x00 bytes, and complete encryption */ for(i=0;i<3;i++) data[((BUF_SZ*2)+5)+i] = 0x00; /* Now, get second-to-last piece of ciphertext */ ulEncryptedDataLen = sizeof(encryptedData); rv = C_EncryptUpdate( hSession, &data[BUF_SZ*2], 8, encryptedData, &ulEncryptedDataLen); . . . /* Get last piece of ciphertext (should have length 0, here) */ ulEncryptedDataLen = sizeof(encryptedData); rv = C_EncryptFinal(hSession, encryptedData, &ulEncryptedDataLen); . . . Download 360.55 Kb. Share with your friends:
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