Making legacy platforms secure
On this page:
HttpWebRequest, Rebex HTTPS makes it possible to use new protocols
and algorithms on both modern and legacy .NET platforms. These include:
- .NET Framework 2.0/3.5/4.0 on Windows XP SP3 or higher
- .NET Framework 4.5-4.8 on Windows 7 SP1 or higher
- .NET Compact Framework 3.5/3.9 on Windows CE 5.0 or higher
- .NET Core 3.0 on Windows, Windows IoT, Linux and macOS
- .NET Core 2.0/2.1/2.2 on Windows, Linux and macOS
- .NET Core 1.0/1.1 on Windows
- Xamarin.Android 8 or higher
- Xamarin.iOS 10.3 or higher
Please note that Rebex HTTPS for .NET Compact Framework 3.5/3.9 is available as a separate product.
HttpWebRequest, Rebex HTTPS makes it possible to use TLS 1.2, TLS 1.1, TLS 1.0, and even legacy SSL 3.0 on all supported .NET platforms.
Most websites already disabled support for outdated SSL 3 protocol. Some even disabled TLS 1.0 and 1.1, and their number will grow in the future. HTTPS clients need to support TLS 1.2 to be able to communicate with those websites.
As of 2017, usage of SHA-1 hash algorithm in X509 certificates has been mostly deprecated - major browsers and operating systems no longer accept server or user certificates with signatures based on SHA-1 hashes, and trusted certification authorities no longer issue such certificates. This means that HTTPS clients with lack of SHA-2 support no longer work.
Rebex HTTPS solves this problem and makes it possible to use certificates signed using SHA-2 on legacy platforms.
Rebex HTTPS offers the following TLS ciphers utilizing message authentication codes based on SHA-2 hash algorithms on all supported platforms:
* Ciphers based on ECDHE or ECDSA need an external plugin on some legacy platforms.
Rebex HTTPS supports Server Name Indication (SNI) on all platforms. SNI is a TLS protocol extension that specifies a way for TLS/SSL clients to indicate to servers which site they are connecting to, which makes it possible to run multiple virtual HTTPS-secured websites on a single IP address.
Support for this is ubiquitous nowadays - unless you use a legacy HTTPS implementation on platforms such as .NET Compact Framework 3.5. In that case, Rebex HTTPS is the solution.
Renegotiation Indication Extension (RFC 5746) fixes a vulnerability in the TLS/SSL protocol that makes it possible for an attacker to hijact TLS/SSL connections during renegotiation in some scenarios.
Elliptic Curve Cryptography (ECC) is an attractive alternative to classic public-key algorithms based on modular exponentiation. Compared to the algorithms such as RSA, DSA or Diffie-Hellman, elliptic curve cryptography offers equivalent security with smaller key sizes.
Rebex HTTPS supports the following elliptic curve TLS ciphers:
And the following curves:
- NIST P-256 curve
- NIST P-384 curve
- NIST P-521 curve
- Brainpool P-256 R1 curve
- Brainpool P-384 R1 curve
- Brainpool P-512 R1 curve
- Curve 25519