Embed a DES implementation rather than relying on lib(x)crypt #7
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Since all of the cryptographic primitives required by asleap (DES, MD4, and SHA1) are obsolete, it is best to ship implementations ourselves rather than rely on external libraries that may deprecate them or remove them altogether. SHA1 is already being supplied by sha1.c, but MD4 is optionally supplied by OpenSSL (libcrypto) and for DES we are relying on the obsolete SVID functions ‘encrypt’ and ‘setkey’. Remove the ifdefs in common.c and genkeys.c allowing for the use of OpenSSL’s implementation of MD4. In the Makefile, remove both -lxcrypt and -lcrypto from LDLIBS, and add md4.o to the link for both asleap and genkeys. This means the program will not compile right now, with undefined references to ‘encrypt’ and ‘setkey’—this will be corrected in the next commit. While we’re messing with the Makefile, overhaul it with proper use of object files, built-in rules and variables, and comprehensive .c:.h dependency lists. While we’re messing with the Makefile, eliminate the only place where we need a -D_LINUX by instead using __GNU_LIBRARY__ to detect the availability of <endian.h>. This *may* mean makefile.cygwin is no longer necessary. Will come back to that.
This implementation was originally written by David Burren for NetBSD and is therefore under a 3-clause BSD license. By using it directly, the Expand and Collapse operations in utils.c cease to be necessary.
- Crank up the warnings level (-Wextra -Wpedantic -Wstrict-prototypes) - Explicitly request C2011 with extensions. - Explicitly request 64-bit off_t. - Fix all the resulting warnings. The only code change of note is that I deleted struct dot11_mgmt from ieee80211.h. This was using the old GNU zero-length array extension in a way that is not supported for C99 flexible array members, and it’s unused in this program, so the easiest fix is to get rid of it.
The only differences are now: - use of .obj and .exe extensions instead of .o and null - -L$(WPDPACK)/lib -lwpcap instead of -lpcap - no ‘strip’ target
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Fixes #5 and #6 (the latter appears to be a duplicate). Also eliminates the dependency on libcrypto (the embedded MD4 implementation is used unconditionally), cleans up the code a little and the Makefiles a whole lot.
I copied the DES implementation over from libxcrypt, since that's the one that I have conveniently to hand. It was originally written for NetBSD and is therefore 3-clause BSD licensed, which I hope is OK.
Note: this compiles cleanly on one computer but has not been tested at all beyond that.