Fix Android compatibility

[yincrash]

Fixes #188 by removing ECDSA signatures in the AndroidConfig.
Add SpongyCastle as the default security provider.

[hierynomus]

This is not complete. If somebody would have called upon SecurityUtils before loading the AndroidConfig, it would break.

[yincrash]

Whoops. I'll fix it and add a test.

[hierynomus]

Fixed this.

[willemw12]

Is this fixed? The changes have not been merged. There is no:

.... SecurityUtils.setSecurityProvider("SC"); ...

in AndroidConfig.java.

[hierynomus]

Correct, The call to SecurityUtils.registerSecurityProvider("org.spongycastle...."); in AndroidConfig does that for you. See https://github.com/hierynomus/sshj/blob/master/src/main/java/net/schmizz/sshj/common/SecurityUtils.java#L73

So yes, this should be fixed. Unless you've found an issue :)

[willemw12]

I could only make SSHJ+SpongyCastle work after temporarily changing isBouncyCastleRegistered() in SecurityUtils.java, from:

return BOUNCY_CASTLE.equals(securityProvider);

into:

return BOUNCY_CASTLE.equals(securityProvider) || "SC".equals(securityProvider);

[hierynomus]

@willemw12 Can you create a new issue for that?

[willemw12]

@hierynomus: See #308.

[hierynomus]

Thanks @willemw12 Will fix it.