Hi all,
I am using: OpenSSL 0.9.7-beta2 16 Jun 2002 configured with: ./Configure solaris-sparcv9-gcc no-asm gcc is "version 2.95.3 20010315 (release)" I had to use no-asm because of intermittent core dumps I was getting in the accelerated bn_sub_words routine. After a lot of debugging, it looked to me like a Sparc chip bug, so I just switched to the non-accelerated version of the routines (speed is not my primary concern). [though I don't believe this is related to the bug I am reporting, for those interested: bn_sub_words was being called with n == 15, and for some reason, some times, the inner loop would keep going into negative n's -- until we crossed into a non-accessible page and core dumped. when I stepped through instruction by instruction (using gdb) it did NOT fail, it also did not fail w/any conditional breakpoint set on the routine -- even if the break was not going to occur. very strange] Back to the point of this bug. I am attempting to calculate a^b % m where a is 2624 bits and b and m are only slightly smaller. See attached files for full details. I believe OpenSSL is producing an incorrect result for all 3 of its modexp routines. BN_mod_exp_recp dies with an error (see comments around USE_RECP #define in bugexptest.c), BN_mod_exp_simple and BN_mod_exp_mont return different results, and both appear to be incorrect. I got the correct result from Gnu MP and by using Verilog as a big number package (and, ironically, from the RTL for our device under test). I am sending a modified exptest.c (which I called bugexptest.c) along with the output of the run. bugexptest was compiled this way (from the test directory in the openssl tree): gcc -I.. -I../include -g -c -o bugexptest.o bugexptest.c gcc -o bugexptest -I.. -I../include -g bugexptest.o -L.. -lcrypto I am sending the files as attachments because Microsoft is evil and didn't provide a way to stop line wrapping when sending an email from Outlook. Please let me know if you have any problems/questions. Thanks, David Asher [EMAIL PROTECTED] ______________________________________________________________________ OpenSSL Project http://www.openssl.org Development Mailing List [EMAIL PROTECTED] Automated List Manager [EMAIL PROTECTED]
