Add minimal tests for 1024-bit RSAZ BN_mod_exp_mont_consttime.

The input base, |a|, isn't reduced mod |m| in the RSAZ case so
incorrect results are given for out-of-range |a| when the RSAZ
implementation is used. On the other hand, the RSAZ implementation is
more correct as far as constant-time operation w.r.t. |a| is concerned.

Change-Id: Iec4d0195cc303ce442ce687a4b7ea42fb19cfd06
Reviewed-on: https://boringssl-review.googlesource.com/12524
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>

crypto/bn/bn_tests.txt

@@ -10387,6 +10387,46 @@ E = d7e6df5d755284929b986cd9b61c9c2c8843f24c711fbdbae1a468edcae15940094372557072
 M = e4e784aa1fa88625a43ba0185a153a929663920be7fe674a4d33c943d3b898cff051482e7050a070cede53be5e89f31515772c7aea637576f99f82708f89d9e244f6ad3a24a02cbe5c0ff7bcf2dad5491f53db7c3f2698a7c41b44f086652f17bb05fe4c5c0a92433c34086b49d7e1825b28bab6c5a9bd0bc95b53d659afa0d7
 
 
+# RSAZ 1024-bit.
+# Note that the lengths of the inputs, especially the *bit* length of |M|, matter a lot.
+
+# Control: No relationship between A and M except that A < M and they're the same number of limbs.
+ModExp = 8984f8c16044f9c0ad7bd72347af90f58e6e003acda92b76e3c7c4a56ea8e918409d8e9b34884d4c89d0b17cb40fe898f2627c084a0f1698e46beccbf6f48eecc281e11ea9e5135adba460ddae157f2c655b5f589ce29b254d43a960a71cede8a08dbb86be4dac22458da232fb1ec2470856827302ed772c9ddafa408c931aa7
+A = 21158da5fe20356825e72b3f5384ec57720d22f727b27ce2f945c8ee311db781add73bf8fae96b775c909bd22fca75c44c2b0584284a5bb1c07f8eefcd6b0a44047a02b185df34f897f11d4fb9a86c9eb841b4cb8d0383441fdc5af3ef385b5e8380f605d73ed41bb42eb2c2a5704d6034b3ad058dafffce83dbbfb6295daaf8
+E = ecdebd112b3b5788669449dcddbd479a203ee9ab72a9bb9c406b97623513bf0ab9a22f1f23634d269e16bfd6d3b64202b71fc355057411967b6ac70f8d9cef0a4e06819a9a18cc06bbe438243fa9759303d98be8a65dc1cb13595ee9b99f138554425d50f6fbc025d8ffa3eaea828d6f3b82a3584146bafde34da257995f0575
+M = ff3a3e023db3bba929ca4ededbace13d0d1264387b5ef62734e177eaf47a78af56b58aacc8ac5d46f5b066bafb95d93d4442bb948653613eec76837b4ffb7991cb080b6c8b403fb09bc817d026e283ee47ab2fc9af274b12f626eda2fe02004a8e27b9ed7d3b614e8955c7e7c2c0700edd079455237c4475fbd41857e206e4b7
+
+# Same as above except A is negative.
+ModExp = 75b54540dd6ec1e87c4e77bb93fd50477ea463fdadb5cab05119b34585d18f971617fc1194240ffa6bdfb53e4785f0a451e03f8c3c444aa6080a96af5906eaa508862a4de15b2c55c023b6f278cd04c1e24fd0711244afeda8e3444256e51261ed99fe66beedb52c43c825b4c7a1adc7d4b111e2208ecd495df91e175573ca10
+A = -21158da5fe20356825e72b3f5384ec57720d22f727b27ce2f945c8ee311db781add73bf8fae96b775c909bd22fca75c44c2b0584284a5bb1c07f8eefcd6b0a44047a02b185df34f897f11d4fb9a86c9eb841b4cb8d0383441fdc5af3ef385b5e8380f605d73ed41bb42eb2c2a5704d6034b3ad058dafffce83dbbfb6295daaf8
+E = ecdebd112b3b5788669449dcddbd479a203ee9ab72a9bb9c406b97623513bf0ab9a22f1f23634d269e16bfd6d3b64202b71fc355057411967b6ac70f8d9cef0a4e06819a9a18cc06bbe438243fa9759303d98be8a65dc1cb13595ee9b99f138554425d50f6fbc025d8ffa3eaea828d6f3b82a3584146bafde34da257995f0575
+M = ff3a3e023db3bba929ca4ededbace13d0d1264387b5ef62734e177eaf47a78af56b58aacc8ac5d46f5b066bafb95d93d4442bb948653613eec76837b4ffb7991cb080b6c8b403fb09bc817d026e283ee47ab2fc9af274b12f626eda2fe02004a8e27b9ed7d3b614e8955c7e7c2c0700edd079455237c4475fbd41857e206e4b7
+
+# A == M - 1 == -1 (mod M) and the exponent is odd so A ^ E (mod M) == A.
+ModExp = b5d257b2c50b050d42f0852eff5cfa2571157c500cd0bd9aa0b2ccdd89c531c9609d520eb81d928fb52b06da25dc713561aa0bd365ee56db9e62ac6787a85936990f44438363560f7af9e0c16f378e5b83f658252390d849401817624da97ec613a1b855fd901847352f434a777e4e32af0cb4033c7547fb6437d067fcd3d964
+A =  b5d257b2c50b050d42f0852eff5cfa2571157c500cd0bd9aa0b2ccdd89c531c9609d520eb81d928fb52b06da25dc713561aa0bd365ee56db9e62ac6787a85936990f44438363560f7af9e0c16f378e5b83f658252390d849401817624da97ec613a1b855fd901847352f434a777e4e32af0cb4033c7547fb6437d067fcd3d964
+E = 61803d4973ae68cfb2ba6770dbed70d36760fa42c01a16d1482eacf0d01adf7a917bc86ece58a73b920295c1291b90f49167ef856ecad149330e1fd49ec71392fb62d47270b53e6d4f3c8f044b80a5736753364896932abc6d872c4c5e135d1edb200597a93ceb262ff6c99079177cd10808b9ed20c8cd7352d80ac7f6963103
+M =  b5d257b2c50b050d42f0852eff5cfa2571157c500cd0bd9aa0b2ccdd89c531c9609d520eb81d928fb52b06da25dc713561aa0bd365ee56db9e62ac6787a85936990f44438363560f7af9e0c16f378e5b83f658252390d849401817624da97ec613a1b855fd901847352f434a777e4e32af0cb4033c7547fb6437d067fcd3d965
+
+# Same inputs as above except A is negative. Note that A mod M with a "correct top" isn't the right length for RSAZ.
+ModExp = 1
+A =  -b5d257b2c50b050d42f0852eff5cfa2571157c500cd0bd9aa0b2ccdd89c531c9609d520eb81d928fb52b06da25dc713561aa0bd365ee56db9e62ac6787a85936990f44438363560f7af9e0c16f378e5b83f658252390d849401817624da97ec613a1b855fd901847352f434a777e4e32af0cb4033c7547fb6437d067fcd3d964
+E = 61803d4973ae68cfb2ba6770dbed70d36760fa42c01a16d1482eacf0d01adf7a917bc86ece58a73b920295c1291b90f49167ef856ecad149330e1fd49ec71392fb62d47270b53e6d4f3c8f044b80a5736753364896932abc6d872c4c5e135d1edb200597a93ceb262ff6c99079177cd10808b9ed20c8cd7352d80ac7f6963103
+M =  b5d257b2c50b050d42f0852eff5cfa2571157c500cd0bd9aa0b2ccdd89c531c9609d520eb81d928fb52b06da25dc713561aa0bd365ee56db9e62ac6787a85936990f44438363560f7af9e0c16f378e5b83f658252390d849401817624da97ec613a1b855fd901847352f434a777e4e32af0cb4033c7547fb6437d067fcd3d965
+
+# A == M, so A == 0 (mod M) so A ^ E (mod M) == 0. Note that A mod M with a "correct top" isn't the right length for RSAZ.
+ModExp = 0
+A =  b5d257b2c50b050d42f0852eff5cfa2571157c500cd0bd9aa0b2ccdd89c531c9609d520eb81d928fb52b06da25dc713561aa0bd365ee56db9e62ac6787a85936990f44438363560f7af9e0c16f378e5b83f658252390d849401817624da97ec613a1b855fd901847352f434a777e4e32af0cb4033c7547fb6437d067fcd3d965
+E = 61803d4973ae68cfb2ba6770dbed70d36760fa42c01a16d1482eacf0d01adf7a917bc86ece58a73b920295c1291b90f49167ef856ecad149330e1fd49ec71392fb62d47270b53e6d4f3c8f044b80a5736753364896932abc6d872c4c5e135d1edb200597a93ceb262ff6c99079177cd10808b9ed20c8cd7352d80ac7f6963103
+M =  b5d257b2c50b050d42f0852eff5cfa2571157c500cd0bd9aa0b2ccdd89c531c9609d520eb81d928fb52b06da25dc713561aa0bd365ee56db9e62ac6787a85936990f44438363560f7af9e0c16f378e5b83f658252390d849401817624da97ec613a1b855fd901847352f434a777e4e32af0cb4033c7547fb6437d067fcd3d965
+
+# A is negative, and A (mod M) is the right length for RSAZ.
+ModExp = 9cf810b9e89d5cbc4b79ae64e123ea06d92965e2bab077df97a1b906dc2e1ddcf96a9c4ed14e2cd96309b829ea9cc2a74a7d4b43c5f34d792a7c583201427754b8f78b783608070a84b61f18913e3ced7f7f530972de7764667c54e29d756eea38a93cd1703c676a4587231b0ebfeadddf908e2877a7a84b5bfc370ecf0d158d
+A =  -8000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
+E = 61803d4973ae68cfb2ba6770dbed70d36760fa42c01a16d1482eacf0d01adf7a917bc86ece58a73b920295c1291b90f49167ef856ecad149330e1fd49ec71392fb62d47270b53e6d4f3c8f044b80a5736753364896932abc6d872c4c5e135d1edb200597a93ceb262ff6c99079177cd10808b9ed20c8cd7352d80ac7f6963103
+M =  b5d257b2c50b050d42f0852eff5cfa2571157c500cd0bd9aa0b2ccdd89c531c9609d520eb81d928fb52b06da25dc713561aa0bd365ee56db9e62ac6787a85936990f44438363560f7af9e0c16f378e5b83f658252390d849401817624da97ec613a1b855fd901847352f434a777e4e32af0cb4033c7547fb6437d067fcd3d965
+
+
 # Exp tests.
 #
 # These test vectors satisfy A ^ E = Exp.