---
title: "SSLGetDiffieHellmanParams(_:_:_:)"
framework: security
role: symbol
role_heading: Function
path: "security/sslgetdiffiehellmanparams(_:_:_:)"
---

# SSLGetDiffieHellmanParams(_:_:_:)

Retrieves the Diffie-Hellman parameters for a given context.

## Declaration

```swift
func SSLGetDiffieHellmanParams(_ context: SSLContext, _ dhParams: UnsafeMutablePointer<UnsafeRawPointer?>, _ dhParamsLen: UnsafeMutablePointer<Int>) -> OSStatus
```

## Parameters

- `context`: An SSL session context reference.
- `dhParams`: On return, points to a buffer containing the Diffie-Hellman parameter block in Open SSL DER format.The returned data is not copied and belongs to the SSL session context reference; therefore, you cannot modify the data and it is released automatically when you dispose of the context.
- `dhParamsLen`: On return, points to the length of the buffer pointed to by the dhParams parameter.

## Return Value

Return Value A result code. See Secure Transport Result Codes.

## Discussion

Discussion This function returns the parameter block specified in an earlier call to the SSLSetDiffieHellmanParams(_:_:_:) function. If that function was never called, the dhParams parameter returns NULL and the dhParamsLen parameter returns 0.