Split src/crypto/ocb.cc into two files – one containing the AES-OCB
implementation backed by OpenSSL, and the other containing
implementations backed by Apple Common Crypto and Nettle. This paves the
way for a new OpenSSL implementation that uses OpenSSL 1.1’s OCB support
directly, rather than one that merely uses OpenSSL to provide the
underlying block cipher.
Remove support for rijndael-alg-fst.c and compiler-provided AES
intrinsics, since they’re not in use anymore. (Mosh can still use
hardware-accelerated AES if it’s available; it just now relies
exclusively on the underlying cryptography library to accelerate AES if
possible.)
Update the build system to conditionally compile in either
ocb_openssl.cc or ocb_internal.cc, depending on which cryptography
library you pass to ./configure.
To make this commit easy to audit, ocb_openssl.cc and ocb_internal.cc
are trivially diffable against ocb.cc (now deleted). Expected diffs
consist of a copyright notice update, a preprocessor check to ensure the
appropriate cryptography implementation has been selected, and deletions
to remove code that’s no longer in use. This does mean a substantial
amount of code is duplicated between ocb_openssl.cc and ocb_internal.cc;
however, ocb_openssl.cc should be completely replaced soon, so it won’t
be an issue in the long term.
Bug: https://github.com/mobile-shell/mosh/issues/1174
Addresses a Debian lintian complaint. Changed the format line in the
debian/copyright file from its proposed form (DEP 5) to the location of
the accepted standard.