### Include CAdESCOM GUIDs File in C

Source: https://cpdn.cryptopro.ru/content/cades/cades-com-usage.html

For C programming, include the `cadescom_i.c` file once in your application to use CAdESCOM GUIDs. Duplicate inclusion will cause a linker error.

```c
#include <cadescom_i.c>

```

--------------------------------

### CryptoPro PKI Developer's Guide - TSP SDK

Source: https://cpdn.cryptopro.ru/content/cades/cadesui.html

Documentation for the CryptoPro TSP SDK, including its usage, installation package creation, and reference to low-level interfaces and client application interfaces.

```APIDOC
## CryptoPro TSP SDK Documentation

### Description
This section details the CryptoPro Time Stamp Protocol (TSP) Software Development Kit (SDK), covering its integration and usage for developers.

### Key Areas

*   **Usage**: Information on how to utilize the TSP SDK.
*   **Installation Package Creation**: Procedures for creating installation packages.
*   **Low-level Interface**: Details on classes like `CAccuracy`, `CMSRequest`, `CMSStamp`, `CRequest`, `CResponse`, `CToken`.
*   **Client Application Interface (C++)**: Information on C++ classes `CRequest`, `CStamp` and functions `FreeMSStamp`, `GetMSStamp`.
*   **Client Application Interface (COM)**: Details on COM interfaces, including `ITSPRequest` with methods like `Import`, `Export`, `Send`, `Display` and properties like `TSAAddress`.
```

--------------------------------

### Get Interface GUID with __uuidof() in C++

Source: https://cpdn.cryptopro.ru/content/cades/cades-com-usage.html

Use the `__uuidof()` operator in C++ to obtain the GUID for CAdESCOM interfaces or classes, for example, when creating an instance.

```cpp
CoCreateInstance(&__uuidof(CadesSignedData), ...);

```

--------------------------------

### C_Initialize

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_general_1gad9e50402e107e29566799a2611d37d3f.html

Initializes the Cryptoki library. This function must be called before any other Cryptoki function, except for C_GetFunctionList. Each application using the library must call this function, and each successful call must be matched by a call to C_Finalize.

```APIDOC
## C_Initialize

### Description
Initializes the Cryptoki library. This function must be the first function called by an application, excluding the call to C_GetFunctionList(). If multiple applications work with the Cryptoki library simultaneously, each must call C_Initialize(). Each successful call to C_Initialize() must be completed by a call to C_Finalize().

### Method
CPRO_PUBLIC_API CK_RV C_Initialize(
  CK_VOID_PTR _pInitArgs
);

### Parameters
#### Arguments
- **_pInitArgs** (CK_VOID_PTR) - Reserved for future use. Note: In this implementation, _pInitArgs cannot be used to pass function parameters.

### Return Values
Upon successful completion, the function returns CKR_OK; otherwise, an error code is returned.

#### Return Codes
- **CKR_CRYPTOKI_ALREADY_INITIALIZED**: The Cryptoki library has already been initialized.
- **CKR_FUNCTION_FAILED**: The function cannot be executed, but this error code does not contain detailed information about the cause of the failure. It is possible that a subsequent call to the function will be successful.
- **CKR_FUNCTION_NOT_SUPPORTED**: Function not supported.

### Notes
Detailed description of the function can be found in the RSA (PKCS#11 v 2.30) documentation.

### Implementation Specifics
- The _pInitArgs parameter is reserved for future use and cannot be used to pass parameters in this implementation.

### Requirements
- **AIX:** 5/6/7 or higher.
- **FreeBSD:** 7/8/9 or higher.
- **Linux:** LSB 3.1 (RHEL 4, SuSE 10) or higher.
- **Solaris:** 10/11 or higher.
- **Mac OSX:** 10.7/8 or higher.
- **iOS:** 6/7 or higher.
- **Windows:** Windows 2000 SP4 or older with Internet Explorer 6.0 or older.
```

--------------------------------

### GostAlgorithmSuite Constructors

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11.html

Provides constructors for the GostAlgorithmSuite class.

```APIDOC
## GostAlgorithmSuite Constructors

### Description
Constructors for the GostAlgorithmSuite class.

### Constructors
- GostAlgorithmSuite()
- GostAlgorithmSuite(Boolean)
```

--------------------------------

### C_VerifyInit

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_verify.html

Initializes a signature verification operation where the signature is appended to the data.

```APIDOC
## C_VerifyInit

### Description
Initializes a signature verification operation where the signature is appended to the data.

### Function Signature
```c
CK_RV C_VerifyInit(CK_SESSION_HANDLE hSession, CK_MECHANISM_PTR pMechanism, CK_OBJECT_HANDLE hKey)
```

### Parameters
#### Input Parameters
- **hSession** (CK_SESSION_HANDLE) - Handle of the session to initialize.
- **pMechanism** (CK_MECHANISM_PTR) - Pointer to a structure that specifies the general mechanism type and its parameters.
- **hKey** (CK_OBJECT_HANDLE) - Handle of the verification key.

### Return Value
- **CK_RV** - Indicates success or failure of the operation.
```

--------------------------------

### ICPX509Enrollment

Source: https://cpdn.cryptopro.ru/content/cades/cadescom_interface.html

Provides methods for creating and installing certificate requests. Extends the IX509Enrollment interface.

```APIDOC
## ICPX509Enrollment

### Description
Provides methods for creating and installing certificate requests. Extends the IX509Enrollment interface.

### Interface
ICPX509Enrollment
```

--------------------------------

### C_VerifyInit

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_verify_1gac4ae2407b1537b61f913599fcf05f471.html

Initializes a signature verification operation. The CKA_VERIFY attribute of the verification key must be CK_TRUE.

```APIDOC
## C_VerifyInit

### Description
Initializes a signature verification operation where the signature is appended to the data. The **CKA_VERIFY** attribute of the verification key must be CK_TRUE.

### Function Signature
```
**CPRO_PUBLIC_API CK_RV** **C_VerifyInit(**
  **CK_SESSION_HANDLE** _hSession_,
  **CK_MECHANISM_PTR** _pMechanism_,
  **CK_OBJECT_HANDLE** _hKey_
**);
```

### Parameters
#### Arguments
- **_hSession_** (CK_SESSION_HANDLE) - The session handle.
- **_pMechanism_** (CK_MECHANISM_PTR) - A pointer to the verification mechanism.
- **_hKey_** (CK_OBJECT_HANDLE) - The handle of the verification key.

### Return Values
Upon successful completion, the function returns CKR_OK, otherwise it returns an error code.

#### Return Codes
- **CKR_OK**: Successful completion.
- **CKR_CRYPTOKI_NOT_INITIALIZED**: The cryptographic interface library has not been initialized.
- **CKR_OPERATION_ACTIVE**: An active operation already exists that prevents Cryptoki from activating this operation.
- **CKR_ARGUMENTS_BAD**: Some of the arguments passed to the function are inappropriate.
- **CKR_SESSION_HANDLE_INVALID**: The session handle was invalid.
- **CKR_KEY_HANDLE_INVALID**: The specified key handle is invalid.
- **CKR_KEY_FUNCTION_NOT_PERMITTED**: An attempt was made to perform a cryptographic operation with a key that does not have the necessary attributes set for this operation.
- **CKR_KEY_TYPE_INCONSISTENT**: The type of the specified key is inconsistent with the mechanism passed to the function.
- **CKR_MECHANISM_INVALID**: An invalid mechanism was passed to the cryptographic operation.
- **CKR_MECHANISM_PARAM_INVALID**: The cryptographic operation was passed a mechanism with invalid parameters.
- **CKR_FUNCTION_FAILED**: The function could not be executed, but this error code does not contain detailed information about the cause of the failure.

### Notes
- For a detailed description of the function, see the RSA (PKCS#11 v 2.30) documents.
- **Implementation Specifics:** The function is implemented in accordance with the requirements of the PKCS#11 standard.
```

--------------------------------

### Token Initialization Functions

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_func.html

Functions for initializing a token and managing PINs.

```APIDOC
## C_InitToken

### Description
Initializes a token with a new PIN and label.

### Method
Not Applicable (Function Call)

### Endpoint
Not Applicable

### Parameters
None explicitly defined in this context.

### Response
None explicitly defined in this context.

## C_InitPIN

### Description
Initializes the PIN for a token.

### Method
Not Applicable (Function Call)

### Endpoint
Not Applicable

### Parameters
None explicitly defined in this context.

### Response
None explicitly defined in this context.

## C_SetPIN

### Description
Sets a new PIN for a token.

### Method
Not Applicable (Function Call)

### Endpoint
Not Applicable

### Parameters
None explicitly defined in this context.

### Response
None explicitly defined in this context.
```

--------------------------------

### C_GetObjectSize Function Signature

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_object_1ga5ed2259aad5ae158234c7d8d5ce43901.html

This is the function signature for C_GetObjectSize, which is used to get the size of a PKCS#11 object.

```c
#define CPRO_PUBLIC_API CK_RV C_GetObjectSize(
  CK_SESSION_HANDLE hSession,
  CK_OBJECT_HANDLE hObject,
  CK_ULONG_PTR pulSize
);
```

--------------------------------

### Display Detached Signature with Page Handling

Source: https://cpdn.cryptopro.ru/content/cades/cadesuisamplepages.html

This C++ snippet demonstrates how to display a detached enhanced electronic digital signature using CadesViewSignatureDetached. It retrieves property pages for the signature and displays them in a property sheet. Ensure necessary setup and imports for C++ and CryptoPro SDK are in place.

```cpp
const BYTE *pDataArray[1];
pDataArray[0] = &original[0];

DWORD cDataArray[1];
cDataArray[0] = (DWORD)original.size();

CADES_VIEW_SIGNATURE_PARA viewPara = { sizeof(viewPara) };
viewPara.dwMsgAndCertEncodingType =  
    X509_ASN_ENCODING | PKCS_7_ASN_ENCODING;

LPPROPSHEETPAGEW *pPropSheetPages = NULL;
DWORD cPropSheetPages = 0;
if (!CadesViewSignatureDetached(0, &viewPara,
&detachedMsg[0], (DWORD)detachedMsg.size(), 1, pDataArray,
cDataArray, &pPropSheetPages, &cPropSheetPages))
{
CadesFreeSignaturePropPages(pPropSheetPages, cPropSheetPages);
std::cout << "CadesViewSignatureDetached() failed." << std::endl;
return;
}

std::vector<HPROPSHEETPAGE> pages(cPropSheetPages);
 
for (DWORD i=0; i<cPropSheetPages; i++)
{
pages[i] = ::CreatePropertySheetPage(pPropSheetPages[i]);
}

PROPSHEETHEADER psh = {};
psh.pszCaption = L"Подпись";
psh.dwSize = sizeof(PROPSHEETHEADER);
psh.hwndParent = NULL;
psh.hInstance = _AtlBaseModule.m_hInst;
psh.nPages = cPropSheetPages;
psh.phpage = &pages[0];
psh.dwFlags = PSH_NOAPPLYNOW | PSH_NOCONTEXTHELP | PSH_USECALLBACK;

INT_PTR ret;
ret = ::PropertySheet(&psh);
if (ret < 0)
{
std::cout << "View Detached Signature failed." << std::endl;
}

CadesFreeSignaturePropPages(pPropSheetPages, cPropSheetPages);
```

--------------------------------

### cputls_init_gost

Source: https://cpdn.cryptopro.ru/content/cades/content-encoding.html

Initializes the GOST TLS context.

```APIDOC
## cputls_init_gost

### Description
Initializes the GOST TLS context.

### Method
Not specified

### Endpoint
Not specified

### Parameters
Not specified

### Request Example
Not specified

### Response
Not specified
```

--------------------------------

### CertOpenSystemStoreW

Source: https://cpdn.cryptopro.ru/content/cades/content-encoding.html

Opens a system certificate store (Unicode).

```APIDOC
## CertOpenSystemStoreW

### Description
Opens a system certificate store (Unicode).

### Method
Not specified

### Endpoint
Not specified

### Parameters
Not specified

### Request Example
Not specified

### Response
Not specified
```

--------------------------------

### C_FindObjectsInit

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_object_1gae6f7dbd6bff888693b3f145ab09faaba.html

Initializes the token object and session object search operation according to the specified template. The search criterion is determined by the template attributes. To search for all objects, set the ulCount parameter to zero. After calling C_FindObjectsInit, the application can call C_FindObjects any number of times to get the handles of objects matching the search template, and finally call C_FindObjectsFinal to end the active search operation. No more than one search operation can be active at a time in this session.

```APIDOC
## C_FindObjectsInit

### Description
Initializes the token object and session object search operation according to the specified template.

### Method
CPRO_PUBLIC_API CK_RV C_FindObjectsInit(
  CK_SESSION_HANDLE hSession,
  CK_ATTRIBUTE_PTR pTemplate,
  CK_ULONG ulCount
);

### Parameters
#### Arguments
- **hSession** (CK_SESSION_HANDLE) - Handle of the session.
- **pTemplate** (CK_ATTRIBUTE_PTR) - Pointer to the search template by attribute values.
- **ulCount** (CK_ULONG) - Number of attributes in the search template.

#### Return Values
Upon successful completion, the function returns CKR_OK; otherwise, it returns an error code.

| Return Codes |
| --- |
| CKR_CRYPTOKI_NOT_INITIALIZED | Function cannot be executed because the token cryptographic interface library was not initialized by the C_Initialize function. |
| CKR_ARGUMENTS_BAD | Some of the arguments passed to the function are unsuitable. |
| CKR_ATTRIBUTE_VALUE_INVALID | An incorrect value for an attribute is specified in the template. |
| CKR_SESSION_HANDLE_INVALID | This session handle was invalid at the time of the function call. It should be remembered that this can happen if the token on which this session was opened was deleted before the function call, as deleting the token closes all sessions opened on it. |
| CKR_OPERATION_ACTIVE | An active operation (or combination of active operations) already exists that does not allow Cryptoki to activate this operation. For example, an active search operation does not allow Cryptoki to activate an encryption operation using the C_EncryptInit function. Or, for example, active hashing and encryption operations do not allow activation of a signature operation. And another example: if the token does not support simultaneous dual cryptographic operations (as indicated by the CKF_DUAL_CRYPTO_OPERATIONS flag in the CK_TOKEN_INFO structure), then an active signature operation will prevent the activation of an encryption operation. |

### Notes
Detailed description of the function can be found in RSA documents (PKCS#11 v 2.30).

### Implementation Specifics
Function is implemented in accordance with PKCS#11 standard requirements. Key selection is limited to searching by "name" and is performed by calling the C_FindObjectsInit function only with the CKA_LABEL attribute.
```

--------------------------------

### C_SignInit

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_sign.html

Initializes a signing operation where the signature is an addition to the data.

```APIDOC
## C_SignInit

### Description
Initializes a signing operation. The signature generated is an addition to the original data.

### Function Signature
```c
CK_RV C_SignInit(CK_SESSION_HANDLE hSession, CK_MECHANISM_PTR pMechanism, CK_OBJECT_HANDLE hKey)
```

### Parameters
*   **hSession** (CK_SESSION_HANDLE) - Required - The session handle.
*   **pMechanism** (CK_MECHANISM_PTR) - Required - Pointer to the mechanism type.
*   **hKey** (CK_OBJECT_HANDLE) - Required - The private key object handle.
```

--------------------------------

### C_InitPIN

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_slot_1gaa49dd5c2835d7f01779ec85d71dcd62e.html

Initializes the PIN for a regular user. This function is part of the PKCS#11 standard but is noted as not implemented in this specific version.

```APIDOC
## C_InitPIN

### Description

Initializes the PIN for a regular user. This function is part of the PKCS#11 standard but is noted as not implemented in this specific version.

### Function Signature

```c
CPRO_PUBLIC_API CK_RV C_InitPIN(
  CK_SESSION_HANDLE hSession,
  CK_CHAR_PTR pPin,
  CK_ULONG ulPinLen
);
```

### Parameters

#### Arguments

- **hSession** (CK_SESSION_HANDLE) - The session handle.
- **pPin** (CK_CHAR_PTR) - Pointer to the regular user's PIN.
- **ulPinLen** (CK_ULONG) - The length of the PIN in bytes.

### Return Values

| Return Code             | Description                                                                                                                               |
| ----------------------- | ----------------------------------------------------------------------------------------------------------------------------------------- |
| CKR_CRYPTOKI_NOT_INITIALIZED | The function cannot be executed because the cryptographic interface library of the token has not been initialized by the C_Initialize() function. |
| CKR_FUNCTION_NOT_SUPPORTED  |                                                                                                                                           |

### Notes

- For a detailed description of the function, refer to the RSA (PKCS#11 v 2.30) documentation.
- **Implementation Specifics:** The function is not implemented. The standard function call interface is preserved.
```

--------------------------------

### CryptoPro PKI Introduction

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11.html

Introduction to CryptoPro PKI and related error codes.

```APIDOC
## Introduction to CryptoPro PKI

This section provides an overview of CryptoPro PKI.

### CryptoPro PKI
General information about the CryptoPro PKI system.

### Error Codes for tspcli.dll and ocspcli.dll
Documentation for error codes returned by the tspcli.dll and ocspcli.dll libraries.
```

--------------------------------

### GostAlgorithmSuite Methods

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11.html

Details the methods available for the GostAlgorithmSuite class.

```APIDOC
## GostAlgorithmSuite Methods

### Description
Methods for checking algorithm support within the GostAlgorithmSuite.

### Methods
- IsAsymmetricKeyLengthSupported()
- IsAsymmetricKeyWrapAlgorithmSupported()
- IsAsymmetricSignatureAlgorithmSupported()
- IsDigestAlgorithmSupported()
- IsEncryptionAlgorithmSupported()
- IsEncryptionKeyDerivationAlgorithmSupported()
- IsSignatureKeyDerivationAlgorithmSupported()
- IsSymmetricKeyLengthSupported()
- IsSymmetricKeyWrapAlgorithmSupported()
- IsSymmetricSignatureAlgorithmSupported()
```

--------------------------------

### C_InitToken

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_slot.html

Initializes a token with a new PIN and label.

```APIDOC
## C_InitToken

### Description

This function initializes the token.

### Method

PKCS#11 Function Call

### Endpoint

N/A (Direct function call)

### Parameters

*   **slotID** (CK_SLOT_ID) - Required - The identifier of the slot containing the token to initialize.
*   **pPIN** (char*) - Required - The new PIN for the token.
*   **pLabel** (char*) - Required - The new label for the token.

### Response

#### Success Response

Indicates successful initialization.

#### Response Example

```json
{
  "status": "CKR_OK"
}
```
```

--------------------------------

### Cryptographic Provider Initialization and Parameters

Source: https://cpdn.cryptopro.ru/content/cades/cadesc-functions.html

Functions for initializing and managing the cryptographic provider context in kernel mode.

```APIDOC
## CPCGetDefaultConfig

### Description
Retrieves the default configuration for the cryptographic provider.

### Method
Not specified (likely a function call in an SDK)

### Endpoint
Not applicable

### Parameters
None specified

### Request Example
None specified

### Response
- **Default Configuration** (Structure/Object) - The default configuration parameters.

### Response Example
None specified

## CPCInitMemoryLF

### Description
Initializes memory for the cryptographic provider, potentially with specific configurations.

### Method
Not specified (likely a function call in an SDK)

### Endpoint
Not applicable

### Parameters
None specified

### Request Example
None specified

### Response
None specified

### Response Example
None specified

## CPCAcquireContext

### Description
Acquires a context for the cryptographic provider.

### Method
Not specified (likely a function call in an SDK)

### Endpoint
Not applicable

### Parameters
None specified

### Request Example
None specified

### Response
- **Context Handle** (Handle/Pointer) - A handle to the acquired context.

### Response Example
None specified

## CPCReleaseContext

### Description
Releases the acquired context for the cryptographic provider.

### Method
Not specified (likely a function call in an SDK)

### Endpoint
Not applicable

### Parameters
- **Context Handle** (Handle/Pointer) - The handle to the context to release.

### Request Example
None specified

### Response
None specified

### Response Example
None specified

## CPCGetProvParam

### Description
Retrieves a parameter of the cryptographic provider.

### Method
Not specified (likely a function call in an SDK)

### Endpoint
Not applicable

### Parameters
- **Parameter ID** (Enum/Integer) - The identifier of the parameter to retrieve.

### Request Example
None specified

### Response
- **Parameter Value** (Various) - The value of the requested parameter.

### Response Example
None specified

## CPCSetProvParam

### Description
Sets a parameter of the cryptographic provider.

### Method
Not specified (likely a function call in an SDK)

### Endpoint
Not applicable

### Parameters
- **Parameter ID** (Enum/Integer) - The identifier of the parameter to set.
- **Parameter Value** (Various) - The new value for the parameter.

### Request Example
None specified

### Response
None specified

### Response Example
None specified

## CPCCreateProvider

### Description
Creates a cryptographic provider instance.

### Method
Not specified (likely a function call in an SDK)

### Endpoint
Not applicable

### Parameters
None specified

### Request Example
None specified

### Response
- **Provider Handle** (Handle/Pointer) - A handle to the created provider.

### Response Example
None specified

## CPCDestroyProvider

### Description
Destroys a cryptographic provider instance.

### Method
Not specified (likely a function call in an SDK)

### Endpoint
Not applicable

### Parameters
- **Provider Handle** (Handle/Pointer) - The handle to the provider to destroy.

### Request Example
None specified

### Response
None specified

### Response Example
None specified
```

--------------------------------

### CertOpenStore

Source: https://cpdn.cryptopro.ru/content/cades/content-encoding.html

Opens a certificate store.

```APIDOC
## CertOpenStore

### Description
Opens a certificate store.

### Method
Not specified

### Endpoint
Not specified

### Parameters
Not specified

### Request Example
Not specified

### Response
Not specified
```

--------------------------------

### Import CAdESCOM DLL in C/C++

Source: https://cpdn.cryptopro.ru/content/cades/cades-com-usage.html

Import the `cadescom.dll` library in your C/C++ application. Ensure the DLL is in the INCLUDE path or the same directory as your source files.

```cpp
#import "cadescom.dll"

```

--------------------------------

### C_SignInit

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_sign_1ga05edc6eed0b2b7525aa30fd232dd2983.html

Initializes a signing operation. The CKA_SIGN attribute of the signing key must be CK_TRUE. The signing operation remains active until C_Sign() or C_SignFinal() is called.

```APIDOC
## C_SignInit

### Description
Initializes a signing operation where the signature is an addition to the data. The CKA_SIGN attribute of the signing key must be CK_TRUE. After calling C_SignInit(), the application can either call C_Sign() to sign the data entirely, or call C_SignUpdate() one or more times, finishing with C_SignFinal(), to sign data in a stream. The signing operation remains active until one of the C_Sign() or C_SignFinal() functions, which actually obtain the signature, is called.

### Method
CPRO_PUBLIC_API CK_RV C_SignInit(
  CK_SESSION_HANDLE hSession,
  CK_MECHANISM_PTR pMechanism,
  CK_OBJECT_HANDLE hKey
);

### Parameters
#### Session Handle
* **hSession** (CK_SESSION_HANDLE) - Handle to the session.

#### Mechanism Pointer
* **pMechanism** (CK_MECHANISM_PTR) - Pointer to the signature mechanism.

#### Key Handle
* **hKey** (CK_OBJECT_HANDLE) - Handle to the signing key.

### Return Values
Upon successful completion, the function returns CKR_OK; otherwise, it returns an error code.

#### Return Codes
* **CKR_CRYPTOKI_NOT_INITIALIZED**: The function cannot be executed because the cryptographic interface library of the token has not been initialized by the C_Initialize() function.
* **CKR_OPERATION_ACTIVE**: An active operation (or combination of active operations) already exists that does not allow Cryptoki to activate this operation. For example, an active search operation does not allow Cryptoki to activate an encryption operation using the C_EncryptInit() function. Or, for example, active hashing and encryption operations do not allow the activation of a signing operation. Another example: if the token does not support simultaneous dual cryptographic operations (indicated by the CKF_DUAL_CRYPTO_OPERATIONS flag in the CK_TOKEN_INFO structure), then an active signing operation will prevent the activation of an encryption operation.
* **CKR_ARGUMENTS_BAD**: Some of the arguments passed to the function are inappropriate.
* **CKR_SESSION_HANDLE_INVALID**: The session handle provided was invalid at the time of the function call. It should be noted that this can happen if the token on which this session was opened was removed before the function call, as removing a token closes all sessions opened on it.
* **CKR_KEY_HANDLE_INVALID**: The specified key handle is invalid. This can happen if the specified handle is a valid handle to some object, but that object is not a key. Note that 0 is never a valid key handle.
* **CKR_MECHANISM_INVALID**: An invalid mechanism was passed to the cryptographic operation. This error code occurs if an unknown mechanism is specified, or if the specified mechanism cannot be used by this function on this token.
* **CKR_MECHANISM_PARAM_INVALID**: A mechanism with invalid parameters was passed to the cryptographic operation. The set of valid parameter values for a given mechanism may vary depending on the token.
* **CKR_KEY_FUNCTION_NOT_PERMITTED**: An attempt was made to perform a cryptographic operation with a key for which the necessary attributes for this operation are not set. For example, if the key is used in an encryption operation, its CKA_ENCRYPT attribute must be set to CK_TRUE (note that a private key cannot have this attribute). This error code has lower priority than CKR_KEY_TYPE_INCONSISTENT.
* **CKR_KEY_TYPE_INCONSISTENT**: The type of the specified key does not match the mechanism passed to the function. This error code has higher priority than CKR_KEY_FUNCTION_NOT_PERMITTED.
* **CKR_FUNCTION_FAILED**: This function cannot be executed, but this error code does not contain detailed information about the reason for failure. However, the situation is not as bad as when CKR_GENERAL_ERROR is returned. Depending on the actual cause of failure, it may be possible that a repeated call to the function will be successful.

### Notes
Detailed description of the function can be found in the RSA (PKCS#11 v 2.30) documents.

### Implementation Specifics
* The function is implemented in accordance with the requirements of the PKCS#11 standard.

### Requirements
* **AIX:** 5/6/7 or higher.
* **FreeBSD:** 7/8/9 or higher.
* **Linux:** LSB 3.1 (RHEL 4, SuSE 10) or higher.
* **Solaris:** 10/11 or higher.
* **Mac OSX:** 10.7/8 or higher.
* **iOS:** 6/7 or higher.
* **Windows 2000 or higher:** Windows 2000 SP4 or older with Internet Explorer 6.0 or older is required.
```

--------------------------------

### C_VerifyInit Function Signature

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_verify_1gac4ae2407b1537b61f913599fcf05f471.html

The C_VerifyInit function initializes a signature verification operation. The verify key's CKA_VERIFY attribute must be CK_TRUE.

```c
CPRO_PUBLIC_API CK_RV C_VerifyInit(
  CK_SESSION_HANDLE hSession,
  CK_MECHANISM_PTR pMechanism,
  CK_OBJECT_HANDLE hKey
);
```

--------------------------------

### C_VerifyRecoverInit

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_verify.html

Initializes a signature verification operation where the data is recovered from the signature.

```APIDOC
## C_VerifyRecoverInit

### Description
Initializes a signature verification operation where the data is recovered from the signature.

### Function Signature
```c
CK_RV C_VerifyRecoverInit(CK_SESSION_HANDLE hSession, CK_MECHANISM_PTR pMechanism, CK_OBJECT_HANDLE hKey)
```

### Parameters
#### Input Parameters
- **hSession** (CK_SESSION_HANDLE) - Handle of the session to initialize.
- **pMechanism** (CK_MECHANISM_PTR) - Pointer to a structure that specifies the general mechanism type and its parameters.
- **hKey** (CK_OBJECT_HANDLE) - Handle of the verification key.

### Return Value
- **CK_RV** - Indicates success or failure of the operation.
```

--------------------------------

### IAbout3 Methods

Source: https://cpdn.cryptopro.ru/

This section details the methods available under the IAbout3 interface, specifically focusing on retrieving CSP version information.

```APIDOC
## IAbout3 CSPVersion

### Description
Retrieves the Cryptographic Service Provider (CSP) version.

### Method
GET

### Endpoint
/IAbout3/CSPVersion

### Response
#### Success Response (200)
- **version** (string) - The version of the CSP.
```

--------------------------------

### C_SignRecoverInit

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_sign.html

Initializes a signing operation where the data is recovered from the signature.

```APIDOC
## C_SignRecoverInit

### Description
Initializes a signing operation where the data is to be recovered from the signature.

### Function Signature
```c
CK_RV C_SignRecoverInit(CK_SESSION_HANDLE hSession, CK_MECHANISM_PTR pMechanism, CK_OBJECT_HANDLE hKey)
```

### Parameters
*   **hSession** (CK_SESSION_HANDLE) - Required - The session handle.
*   **pMechanism** (CK_MECHANISM_PTR) - Required - Pointer to the mechanism type.
*   **hKey** (CK_OBJECT_HANDLE) - Required - The private key object handle.
```

--------------------------------

### C_DigestInit

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_digest_1gaf1740da489b565e8e4858afae768a90a.html

Initializes a data digesting operation.

```APIDOC
## C_DigestInit

### Description
Initializes a data digesting operation. The application can then call C_Digest to digest data in its entirety, or call C_DigestUpdate zero or more times, finishing with C_DigestFinal, to digest data in a stream.

### Method
C_DigestInit

### Parameters
#### Session Handle
- **hSession** (CK_SESSION_HANDLE) - The session handle.

#### Mechanism Pointer
- **pMechanism** (CK_MECHANISM_PTR) - A pointer to the digesting mechanism.

### Return Values
- **CKR_OK**: Successful completion.
- **CKR_CRYPTOKI_NOT_INITIALIZED**: The cryptographic interface library was not initialized.
- **CKR_OPERATION_ACTIVE**: An active operation prevents this operation from being activated.
- **CKR_ARGUMENTS_BAD**: Invalid arguments were passed to the function.
- **CKR_SESSION_HANDLE_INVALID**: The session handle is invalid.
- **CKR_MECHANISM_INVALID**: An invalid mechanism was passed to the cryptographic operation.
- **CKR_MECHANISM_PARAM_INVALID**: The mechanism has invalid parameters.
- **CKR_FUNCTION_FAILED**: The function could not be executed, but without detailed information.
```

--------------------------------

### CertOpenSystemStoreA

Source: https://cpdn.cryptopro.ru/content/cades/content-encoding.html

Opens a system certificate store (ANSI).

```APIDOC
## CertOpenSystemStoreA

### Description
Opens a system certificate store (ANSI).

### Method
Not specified

### Endpoint
Not specified

### Parameters
Not specified

### Request Example
Not specified

### Response
Not specified
```

--------------------------------

### C_EncryptUpdate

Source: https://cpdn.cryptopro.ru/content/PKCS1150r4/html/group___pro_p_k_c_s11_encrypt_1gae2c8c9ee6e1ee8b63131459291458c58.html

Continues a data encryption operation in a stream, processing the next chunk of data. The encryption operation must be initialized with the C_EncryptInit function. This function can be called sequentially any number of times. Restrictions are imposed on the length of input data for block encryption modes - the input data must consist of an integer number of blocks. If these restrictions are not met, the C_EncryptUpdate function fails and returns the error CKR_DATA_LEN_RANGE. Encrypted data can be returned to the same address to which the input data was passed, i.e., the _pPart_ and _pEncryptedPart_ parameters can be the same.

```APIDOC
## C_EncryptUpdate

### Description
Continues a data encryption operation in a stream, processing the next chunk of data. The encryption operation must be initialized with the C_EncryptInit function. This function can be called sequentially any number of times.

### Method
CPRO_PUBLIC_API CK_RV C_EncryptUpdate(
  CK_SESSION_HANDLE hSession,
  CK_BYTE_PTR pPart,
  CK_ULONG ulPartLen,
  CK_BYTE_PTR pEncryptedPart,
  CK_ULONG_PTR pulEncryptedPartLen
);

### Parameters
#### Arguments
- **hSession** (CK_SESSION_HANDLE) - The session handle.
- **pPart** (CK_BYTE_PTR) - Pointer to the next part of the data.
- **ulPartLen** (CK_ULONG) - The length of the next part of the data.
- **pEncryptedPart** (CK_BYTE_PTR) - The address where the encrypted part of the data is returned.
- **pulEncryptedPartLen** (CK_ULONG_PTR) - The address where the length of the encrypted part of the data in bytes is returned.

### Return Values
Upon successful completion, the function returns CKR_OK; otherwise, it returns an error code.

#### Return Codes
- **CKR_OK**: Successful completion.
- **CKR_CRYPTOKI_NOT_INITIALIZED**: The cryptographic interface library of the token has not been initialized.
- **CKR_OPERATION_NOT_INITIALIZED**: No active operation of the corresponding type exists in this session.
- **CKR_ARGUMENTS_BAD**: Some of the arguments passed to the function are unsuitable.
- **CKR_SESSION_HANDLE_INVALID**: The session handle was invalid during the function call.
- **CKR_DATA_LEN_RANGE**: The cryptographic operation was passed open input data with an incorrect length.
- **CKR_BUFFER_TOO_SMALL**: The buffer size is insufficient to return the necessary data.
- **CKR_FUNCTION_FAILED**: The function could not be executed, but this error code does not contain detailed information about the cause of the failure.

### Notes
- Detailed description of the function can be found in the RSA (PKCS#11 v 2.30) documents.
- Implementation specifics: The function is implemented in accordance with the requirements of the PKCS#11 standard.
```