Ticket History #6665: Fix cipher state chaining in OpenSSL back end

pull up r23734 from trunk

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r23734 | ghudson | 2010-02-18 13:04:47 -0500 (Thu, 18 Feb 2010) | 17 lines

ticket: 6665
subject: Fix cipher state chaining in OpenSSL back end
target_version: 1.8
tags: pullup

Make cipher state chaining work in the OpenSSL back end for des, des3,
and arcfour enc providers. Subtleties:

* DES and DES3 have checks to avoid clobbering ivec with uninitialized
data if there is no data to encrypt.
* Arcfour saves the OpenSSL cipher context across calls. To protect
against a caller improperly copying the state (which happens to work
with other enc providers), a loopback pointer is used, as in GSSAPI.
* EVP_EncryptFinal_ex is unnecessary with stream ciphers and would
interfere with cipher state chaining if it did anything, so just
remove it.

https://github.com/krb5/krb5/commit/03aaf16911afdbb9b5189168c831c550f246cb22
Commit By: tlyu
Revision: 23746
Changed Files:
U branches/krb5-1-8/src/lib/crypto/openssl/enc_provider/des.c
U branches/krb5-1-8/src/lib/crypto/openssl/enc_provider/des3.c
U branches/krb5-1-8/src/lib/crypto/openssl/enc_provider/rc4.c