Check that the bn_isqrt -C output isn't changed

bn_isqrt -C generates code included in lib/libcrypto/lib/bn_isqrt.c. The
regress tests already ensure that the content of the tables don't change.
Ensure further that the code generation doesn't get out of sync.

2 files changed, 43 insertions, 1 deletions

diff --git a/src/regress/lib/libcrypto/bn/Makefile b/src/regress/lib/libcrypto/bn/Makefile
index b5d146c71b..7dc5ef75c8 100644
--- a/src/regress/lib/libcrypto/bn/Makefile
+++ b/src/regress/lib/libcrypto/bn/Makefile
@@ -1,4 +1,4 @@
-#       $OpenBSD: Makefile,v 1.9 2022/12/01 21:21:51 tb Exp $
+#       $OpenBSD: Makefile,v 1.10 2022/12/01 22:31:59 tb Exp $
 
 PROGS +=        bn_add_sub
 PROGS +=        bn_cmp
@@ -32,9 +32,21 @@ run-$p: $p
         ./$p
 .endfor
 
+# Verify that the bn_isqrt -C output isn't changed by accident.
 isqrt-print-tables: bn_isqrt
         @./bn_isqrt -C
 
+CLEANFILES += bn_isqrt_gen_tables.txt.tmp bn_isqrt_gen_tables.txt
+bn_isqrt_gen_tables.txt: bn_isqrt
+        ${.MAKE} -C ${.CURDIR} isqrt-print-tables > $@.tmp
+        mv -f $@.tmp $@
+
+REGRESS_TARGETS +=      run-bn_isqrt_check_tables
+.PHONY:                 run-bn_isqrt_check_tables
+run-bn_isqrt_check_tables: bn_isqrt_gen_tables.txt
+        diff -pu ${.CURDIR}/bn_isqrt_tables.txt bn_isqrt_gen_tables.txt
+
+
 # Keep bn_test last since it is special
 PROGS +=        bn_test
 STATIC_LINK +=  bn_test
diff --git a/src/regress/lib/libcrypto/bn/bn_isqrt_tables.txt b/src/regress/lib/libcrypto/bn/bn_isqrt_tables.txt
new file mode 100644
index 0000000000..bc045a220e
--- /dev/null
+++ b/src/regress/lib/libcrypto/bn/bn_isqrt_tables.txt
@@ -0,0 +1,30 @@
+const uint8_t is_square_mod_11[] = {
+        1, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0,
+};
+CTASSERT(sizeof(is_square_mod_11) == 11);
+
+const uint8_t is_square_mod_63[] = {
+        1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0,
+        1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0,
+        0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0,
+        0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0,
+};
+CTASSERT(sizeof(is_square_mod_63) == 63);
+
+const uint8_t is_square_mod_64[] = {
+        1, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0,
+        1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0,
+        0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0,
+        0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0,
+};
+CTASSERT(sizeof(is_square_mod_64) == 64);
+
+const uint8_t is_square_mod_65[] = {
+        1, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0,
+        1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0,
+        0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0,
+        0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0,
+        1,
+};
+CTASSERT(sizeof(is_square_mod_65) == 65);
+