Follow-up Comment #2, bug #18170 (project freeciv): Can't reproduce on my x86_64 machine -- the code gives the right answer for the example given. A possibly relevant difference is that sparc64 is big-endian whereas x86_64 is little-endian.
In fact, I'm pretty sure that's what it is. This code relies on dubious casts between octets and uint32s, and to this end it defines a SWAP() macro that depends on whether WORDS_BIGENDIAN is defined. Only there's no reason for that ever to be defined in the Freeciv codebase (the magic to work it out is protected by _LIBC, which I doubt is defined for us and wouldn't work anyway). So, I think it can only ever work on little-endian machines. Probable proof of the pudding: if I define WORDS_BIGENDIAN on my little-endian machine, create_md5sum() gives the same result as the erroneous one in comment #0. My inclination is to find a more portable implementation of md5sum, rather than trying to fix up this one. (For the record, before I realised the above I had a look at what I think is the upstream version (git history <http://sourceware.org/git/?p=glibc.git;a=history;f=crypt/md5.c;h=922e7cc7e97352f81fde0a076fdb11886bbec7ce;hb=refs/heads/master>); there's not been any significant change since 2005, and I don't see significant differences in the number-crunching bits between ours and theirs.) I assume the effect of this bug is that authentication databases may not be portable from one server to another of a different architecture; in this case the server operator will effectively lose all their passwords. I don't think it affects interoperability between clients and servers? Conversely, the effect of *fixing* this bug is that any big-endian server operators will effectively lose all their passwords (unless we put in a backwards-compatibility wart). Probably not one to drop into a stable release update, then. _______________________________________________________ Reply to this item at: <http://gna.org/bugs/?18170> _______________________________________________ Message sent via/by Gna! http://gna.org/ _______________________________________________ Freeciv-dev mailing list Freeciv-dev@gna.org https://mail.gna.org/listinfo/freeciv-dev
