Re: pgcrypto & strong ciphers limitation

Just confirming, this should be applied to 8.3, right?

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Zdenek Kotala wrote:
> Stefan reported me that prcrypto regression test fails on solaris 10
> with openssl support. I investigated this problem and the result is that
> Solaris 10 delivers only support for short keys up to 128. Strong crypto
> (SUNWcry and SUNWcryr packages) is available on web download pages. (It
> is result of US crypto export policy.)
>
> However, on default installation (which is commonly used) it is a
> problem. Regression test cannot be fixed because it tests strong
> ciphers, but there two very strange issue:
>
> 1) First issue is blowfish cipher. Because pgcrypto uses old interface
> instead new "evp" it calls bf_set_key function which does not return any
> output and cut key if it is too long. See
> http://src.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/common/openssl/crypto/bf/bf_skey.c
> line 84.
>
> If user installs strong crypto he will not be able decrypt data which
> has been encrypted before.
>
> The fix of this issue is ugly, because there is not way how to verify
> supported key length with old openssl API and only new API return err if
> length is not supported.
>
>
> 2) AES ciphere crashes when key is longer. It happens because return
> value from AES_set_encrypt_key is ignored and AES_encrypt is called with
> uninitialized structure.
>
>
> I attach patch which fix both issues, but main problem is there that old
> openssl API is used and supported key lengths are hardcoded. I think we
> can add to TODO list rewrite pgcrypto to use evp openssl interface.
>
>
> Any comments?
>
> Zdenek
>

>
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