[Breaking change]: RSA.EncryptValue and RSA.DecryptValue are obsolete

[vcsjones]

Description

RSA.EncryptValue and RSA.DecryptValue are obsolete with the SYSLIB0048 diagnostic code.

This obsoletion is for .NET 8 Preview 1.

Version

Other (please put exact version in description textbox)

Previous behavior

Callers could use RSA.EncryptValue or RSA.EncryptValue without a warning.

New behavior

In .NET 8, users of RSA.EncryptValue or RSA.EncryptValue will get a SYSLIB0048 compilation warning.

Type of breaking change

• Binary incompatible: Existing binaries may encounter a breaking change in behavior, such as failure to load/execute or different run-time behavior.
• Source incompatible: Source code may encounter a breaking change in behavior when targeting the new runtime/component/SDK, such as compile errors or different run-time behavior.

Reason for change

These APIs were never implemented and always produced a NotSupportedException. Their purpose is unclear and should not be used.

Recommended action

Callers that want to encrypt or decrypt with RSA should use Encrypt or Decrypt instead.

Feature area

Cryptography

Affected APIs

• M:System.Security.Cryptography.RSACryptoServiceProvider.EncryptValue(System.Byte[])
• M:System.Security.Cryptography.RSACryptoServiceProvider.DecryptValue(System.Byte[])
• M:System.Security.Cryptography.RSA.EncryptValue(System.Byte[])
• M:System.Security.Cryptography.RSA.DecryptValue(System.Byte[])

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Associated WorkItem - 60624