diff --git a/ap/lib/libssl/openssl-1.1.1o/test/bntest.c b/ap/lib/libssl/openssl-1.1.1o/test/bntest.c
new file mode 100644
index 0000000..9273e86
--- /dev/null
+++ b/ap/lib/libssl/openssl-1.1.1o/test/bntest.c
@@ -0,0 +1,2972 @@
+/*
+ * Copyright 1995-2022 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+#include <assert.h>
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+
+#include <openssl/bn.h>
+#include <openssl/crypto.h>
+#include <openssl/err.h>
+#include <openssl/rand.h>
+#include "internal/nelem.h"
+#include "internal/numbers.h"
+#include "testutil.h"
+
+#ifdef OPENSSL_SYS_WINDOWS
+# define strcasecmp _stricmp
+#endif
+
+/*
+ * Things in boring, not in openssl.  TODO we should add them.
+ */
+#define HAVE_BN_SQRT 0
+
+typedef struct filetest_st {
+    const char *name;
+    int (*func)(STANZA *s);
+} FILETEST;
+
+typedef struct mpitest_st {
+    const char *base10;
+    const char *mpi;
+    size_t mpi_len;
+} MPITEST;
+
+static const int NUM0 = 100;           /* number of tests */
+static const int NUM1 = 50;            /* additional tests for some functions */
+static BN_CTX *ctx;
+
+/*
+ * Polynomial coefficients used in GFM tests.
+ */
+#ifndef OPENSSL_NO_EC2M
+static int p0[] = { 163, 7, 6, 3, 0, -1 };
+static int p1[] = { 193, 15, 0, -1 };
+#endif
+
+/*
+ * Look for |key| in the stanza and return it or NULL if not found.
+ */
+static const char *findattr(STANZA *s, const char *key)
+{
+    int i = s->numpairs;
+    PAIR *pp = s->pairs;
+
+    for ( ; --i >= 0; pp++)
+        if (strcasecmp(pp->key, key) == 0)
+            return pp->value;
+    return NULL;
+}
+
+/*
+ * Parse BIGNUM from sparse hex-strings, return |BN_hex2bn| result.
+ */
+static int parse_bigBN(BIGNUM **out, const char *bn_strings[])
+{
+    char *bigstring = glue_strings(bn_strings, NULL);
+    int ret = BN_hex2bn(out, bigstring);
+
+    OPENSSL_free(bigstring);
+    return ret;
+}
+
+/*
+ * Parse BIGNUM, return number of bytes parsed.
+ */
+static int parseBN(BIGNUM **out, const char *in)
+{
+    *out = NULL;
+    return BN_hex2bn(out, in);
+}
+
+static int parsedecBN(BIGNUM **out, const char *in)
+{
+    *out = NULL;
+    return BN_dec2bn(out, in);
+}
+
+static BIGNUM *getBN(STANZA *s, const char *attribute)
+{
+    const char *hex;
+    BIGNUM *ret = NULL;
+
+    if ((hex = findattr(s, attribute)) == NULL) {
+        TEST_error("%s:%d: Can't find %s", s->test_file, s->start, attribute);
+        return NULL;
+    }
+
+    if (parseBN(&ret, hex) != (int)strlen(hex)) {
+        TEST_error("Could not decode '%s'", hex);
+        return NULL;
+    }
+    return ret;
+}
+
+static int getint(STANZA *s, int *out, const char *attribute)
+{
+    BIGNUM *ret;
+    BN_ULONG word;
+    int st = 0;
+
+    if (!TEST_ptr(ret = getBN(s, attribute))
+            || !TEST_ulong_le(word = BN_get_word(ret), INT_MAX))
+        goto err;
+
+    *out = (int)word;
+    st = 1;
+ err:
+    BN_free(ret);
+    return st;
+}
+
+static int equalBN(const char *op, const BIGNUM *expected, const BIGNUM *actual)
+{
+    if (BN_cmp(expected, actual) == 0)
+        return 1;
+
+    TEST_error("unexpected %s value", op);
+    TEST_BN_eq(expected, actual);
+    return 0;
+}
+
+/*
+ * Return a "random" flag for if a BN should be negated.
+ */
+static int rand_neg(void)
+{
+    static unsigned int neg = 0;
+    static int sign[8] = { 0, 0, 0, 1, 1, 0, 1, 1 };
+
+    return sign[(neg++) % 8];
+}
+
+static int test_swap(void)
+{
+    BIGNUM *a = NULL, *b = NULL, *c = NULL, *d = NULL;
+    int top, cond, st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b = BN_new())
+            || !TEST_ptr(c = BN_new())
+            || !TEST_ptr(d = BN_new()))
+        goto err;
+
+    if (!(TEST_true(BN_bntest_rand(a, 1024, 1, 0))
+            && TEST_true(BN_bntest_rand(b, 1024, 1, 0))
+            && TEST_ptr(BN_copy(c, a))
+            && TEST_ptr(BN_copy(d, b))))
+        goto err;
+    top = BN_num_bits(a) / BN_BITS2;
+
+    /* regular swap */
+    BN_swap(a, b);
+    if (!equalBN("swap", a, d)
+            || !equalBN("swap", b, c))
+        goto err;
+
+    /* conditional swap: true */
+    cond = 1;
+    BN_consttime_swap(cond, a, b, top);
+    if (!equalBN("cswap true", a, c)
+            || !equalBN("cswap true", b, d))
+        goto err;
+
+    /* conditional swap: false */
+    cond = 0;
+    BN_consttime_swap(cond, a, b, top);
+    if (!equalBN("cswap false", a, c)
+            || !equalBN("cswap false", b, d))
+        goto err;
+
+    /* same tests but checking flag swap */
+    BN_set_flags(a, BN_FLG_CONSTTIME);
+
+    BN_swap(a, b);
+    if (!equalBN("swap, flags", a, d)
+            || !equalBN("swap, flags", b, c)
+            || !TEST_true(BN_get_flags(b, BN_FLG_CONSTTIME))
+            || !TEST_false(BN_get_flags(a, BN_FLG_CONSTTIME)))
+        goto err;
+
+    cond = 1;
+    BN_consttime_swap(cond, a, b, top);
+    if (!equalBN("cswap true, flags", a, c)
+            || !equalBN("cswap true, flags", b, d)
+            || !TEST_true(BN_get_flags(a, BN_FLG_CONSTTIME))
+            || !TEST_false(BN_get_flags(b, BN_FLG_CONSTTIME)))
+        goto err;
+
+    cond = 0;
+    BN_consttime_swap(cond, a, b, top);
+    if (!equalBN("cswap false, flags", a, c)
+            || !equalBN("cswap false, flags", b, d)
+            || !TEST_true(BN_get_flags(a, BN_FLG_CONSTTIME))
+            || !TEST_false(BN_get_flags(b, BN_FLG_CONSTTIME)))
+        goto err;
+
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(c);
+    BN_free(d);
+    return st;
+}
+
+static int test_sub(void)
+{
+    BIGNUM *a = NULL, *b = NULL, *c = NULL;
+    int i, st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b = BN_new())
+            || !TEST_ptr(c = BN_new()))
+        goto err;
+
+    for (i = 0; i < NUM0 + NUM1; i++) {
+        if (i < NUM1) {
+            if (!(TEST_true(BN_bntest_rand(a, 512, 0, 0)))
+                    && TEST_ptr(BN_copy(b, a))
+                    && TEST_int_ne(BN_set_bit(a, i), 0)
+                    && TEST_true(BN_add_word(b, i)))
+                goto err;
+        } else {
+            if (!TEST_true(BN_bntest_rand(b, 400 + i - NUM1, 0, 0)))
+                goto err;
+            BN_set_negative(a, rand_neg());
+            BN_set_negative(b, rand_neg());
+        }
+        if (!(TEST_true(BN_sub(c, a, b))
+                && TEST_true(BN_add(c, c, b))
+                && TEST_true(BN_sub(c, c, a))
+                && TEST_BN_eq_zero(c)))
+            goto err;
+    }
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(c);
+    return st;
+}
+
+static int test_div_recip(void)
+{
+    BIGNUM *a = NULL, *b = NULL, *c = NULL, *d = NULL, *e = NULL;
+    BN_RECP_CTX *recp = NULL;
+    int st = 0, i;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b = BN_new())
+            || !TEST_ptr(c = BN_new())
+            || !TEST_ptr(d = BN_new())
+            || !TEST_ptr(e = BN_new())
+            || !TEST_ptr(recp = BN_RECP_CTX_new()))
+        goto err;
+
+    for (i = 0; i < NUM0 + NUM1; i++) {
+        if (i < NUM1) {
+            if (!(TEST_true(BN_bntest_rand(a, 400, 0, 0))
+                    && TEST_ptr(BN_copy(b, a))
+                    && TEST_true(BN_lshift(a, a, i))
+                    && TEST_true(BN_add_word(a, i))))
+                goto err;
+        } else {
+            if (!(TEST_true(BN_bntest_rand(b, 50 + 3 * (i - NUM1), 0, 0))))
+                goto err;
+        }
+        BN_set_negative(a, rand_neg());
+        BN_set_negative(b, rand_neg());
+        if (!(TEST_true(BN_RECP_CTX_set(recp, b, ctx))
+                && TEST_true(BN_div_recp(d, c, a, recp, ctx))
+                && TEST_true(BN_mul(e, d, b, ctx))
+                && TEST_true(BN_add(d, e, c))
+                && TEST_true(BN_sub(d, d, a))
+                && TEST_BN_eq_zero(d)))
+            goto err;
+    }
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(c);
+    BN_free(d);
+    BN_free(e);
+    BN_RECP_CTX_free(recp);
+    return st;
+}
+
+static struct {
+    int n, divisor, result, remainder;
+} signed_mod_tests[] = {
+    {  10,   3,   3,   1 },
+    { -10,   3,  -3,  -1 },
+    {  10,  -3,  -3,   1 },
+    { -10,  -3,   3,  -1 },
+};
+
+static BIGNUM *set_signed_bn(int value)
+{
+    BIGNUM *bn = BN_new();
+
+    if (bn == NULL)
+        return NULL;
+    if (!BN_set_word(bn, value < 0 ? -value : value)) {
+        BN_free(bn);
+        return NULL;
+    }
+    BN_set_negative(bn, value < 0);
+    return bn;
+}
+
+static int test_signed_mod_replace_ab(int n)
+{
+    BIGNUM *a = NULL, *b = NULL, *c = NULL, *d = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(a = set_signed_bn(signed_mod_tests[n].n))
+            || !TEST_ptr(b = set_signed_bn(signed_mod_tests[n].divisor))
+            || !TEST_ptr(c = set_signed_bn(signed_mod_tests[n].result))
+            || !TEST_ptr(d = set_signed_bn(signed_mod_tests[n].remainder)))
+        goto err;
+
+    if (TEST_true(BN_div(a, b, a, b, ctx))
+            && TEST_BN_eq(a, c)
+            && TEST_BN_eq(b, d))
+        st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(c);
+    BN_free(d);
+    return st;
+}
+
+static int test_signed_mod_replace_ba(int n)
+{
+    BIGNUM *a = NULL, *b = NULL, *c = NULL, *d = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(a = set_signed_bn(signed_mod_tests[n].n))
+            || !TEST_ptr(b = set_signed_bn(signed_mod_tests[n].divisor))
+            || !TEST_ptr(c = set_signed_bn(signed_mod_tests[n].result))
+            || !TEST_ptr(d = set_signed_bn(signed_mod_tests[n].remainder)))
+        goto err;
+
+    if (TEST_true(BN_div(b, a, a, b, ctx))
+            && TEST_BN_eq(b, c)
+            && TEST_BN_eq(a, d))
+        st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(c);
+    BN_free(d);
+    return st;
+}
+
+static int test_mod(void)
+{
+    BIGNUM *a = NULL, *b = NULL, *c = NULL, *d = NULL, *e = NULL;
+    int st = 0, i;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b = BN_new())
+            || !TEST_ptr(c = BN_new())
+            || !TEST_ptr(d = BN_new())
+            || !TEST_ptr(e = BN_new()))
+        goto err;
+
+    if (!(TEST_true(BN_bntest_rand(a, 1024, 0, 0))))
+        goto err;
+    for (i = 0; i < NUM0; i++) {
+        if (!(TEST_true(BN_bntest_rand(b, 450 + i * 10, 0, 0))))
+            goto err;
+        BN_set_negative(a, rand_neg());
+        BN_set_negative(b, rand_neg());
+        if (!(TEST_true(BN_mod(c, a, b, ctx))
+                && TEST_true(BN_div(d, e, a, b, ctx))
+                && TEST_BN_eq(e, c)
+                && TEST_true(BN_mul(c, d, b, ctx))
+                && TEST_true(BN_add(d, c, e))
+                && TEST_BN_eq(d, a)))
+            goto err;
+    }
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(c);
+    BN_free(d);
+    BN_free(e);
+    return st;
+}
+
+static const char *bn1strings[] = {
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00000000000000FFFFFFFF00",
+    "0000000000000000000000000000000000000000000000000000000000000000",
+    "0000000000000000000000000000000000000000000000000000000000000000",
+    "0000000000000000000000000000000000000000000000000000000000000000",
+    "0000000000000000000000000000000000000000000000000000000000000000",
+    "0000000000000000000000000000000000000000000000000000000000000000",
+    "0000000000000000000000000000000000000000000000000000000000000000",
+    "0000000000000000000000000000000000000000000000000000000000000000",
+    "00000000000000000000000000000000000000000000000000FFFFFFFFFFFFFF",
+    NULL
+};
+
+static const char *bn2strings[] = {
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00000000000000FFFFFFFF0000000000",
+    "0000000000000000000000000000000000000000000000000000000000000000",
+    "0000000000000000000000000000000000000000000000000000000000000000",
+    "0000000000000000000000000000000000000000000000000000000000000000",
+    "0000000000000000000000000000000000000000000000000000000000000000",
+    "0000000000000000000000000000000000000000000000000000000000000000",
+    "0000000000000000000000000000000000000000000000000000000000000000",
+    "0000000000000000000000000000000000000000000000000000000000000000",
+    "000000000000000000000000000000000000000000FFFFFFFFFFFFFF00000000",
+    NULL
+};
+
+/*
+ * Test constant-time modular exponentiation with 1024-bit inputs, which on
+ * x86_64 cause a different code branch to be taken.
+ */
+static int test_modexp_mont5(void)
+{
+    BIGNUM *a = NULL, *p = NULL, *m = NULL, *d = NULL, *e = NULL;
+    BIGNUM *b = NULL, *n = NULL, *c = NULL;
+    BN_MONT_CTX *mont = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(p = BN_new())
+            || !TEST_ptr(m = BN_new())
+            || !TEST_ptr(d = BN_new())
+            || !TEST_ptr(e = BN_new())
+            || !TEST_ptr(b = BN_new())
+            || !TEST_ptr(n = BN_new())
+            || !TEST_ptr(c = BN_new())
+            || !TEST_ptr(mont = BN_MONT_CTX_new()))
+        goto err;
+
+    /* must be odd for montgomery */
+    if (!(TEST_true(BN_bntest_rand(m, 1024, 0, 1))
+            /* Zero exponent */
+            && TEST_true(BN_bntest_rand(a, 1024, 0, 0))))
+        goto err;
+    BN_zero(p);
+
+    if (!TEST_true(BN_mod_exp_mont_consttime(d, a, p, m, ctx, NULL)))
+        goto err;
+    if (!TEST_BN_eq_one(d))
+        goto err;
+
+    /* Regression test for carry bug in mulx4x_mont */
+    if (!(TEST_true(BN_hex2bn(&a,
+        "7878787878787878787878787878787878787878787878787878787878787878"
+        "7878787878787878787878787878787878787878787878787878787878787878"
+        "7878787878787878787878787878787878787878787878787878787878787878"
+        "7878787878787878787878787878787878787878787878787878787878787878"))
+        && TEST_true(BN_hex2bn(&b,
+        "095D72C08C097BA488C5E439C655A192EAFB6380073D8C2664668EDDB4060744"
+        "E16E57FB4EDB9AE10A0CEFCDC28A894F689A128379DB279D48A2E20849D68593"
+        "9B7803BCF46CEBF5C533FB0DD35B080593DE5472E3FE5DB951B8BFF9B4CB8F03"
+        "9CC638A5EE8CDD703719F8000E6A9F63BEED5F2FCD52FF293EA05A251BB4AB81"))
+        && TEST_true(BN_hex2bn(&n,
+        "D78AF684E71DB0C39CFF4E64FB9DB567132CB9C50CC98009FEB820B26F2DED9B"
+        "91B9B5E2B83AE0AE4EB4E0523CA726BFBE969B89FD754F674CE99118C3F2D1C5"
+        "D81FDC7C54E02B60262B241D53C040E99E45826ECA37A804668E690E1AFC1CA4"
+        "2C9A15D84D4954425F0B7642FC0BD9D7B24E2618D2DCC9B729D944BADACFDDAF"))))
+        goto err;
+
+    if (!(TEST_true(BN_MONT_CTX_set(mont, n, ctx))
+            && TEST_true(BN_mod_mul_montgomery(c, a, b, mont, ctx))
+            && TEST_true(BN_mod_mul_montgomery(d, b, a, mont, ctx))
+            && TEST_BN_eq(c, d)))
+        goto err;
+
+    /* Regression test for carry bug in sqr[x]8x_mont */
+    if (!(TEST_true(parse_bigBN(&n, bn1strings))
+            && TEST_true(parse_bigBN(&a, bn2strings))))
+        goto err;
+    BN_free(b);
+    if (!(TEST_ptr(b = BN_dup(a))
+            && TEST_true(BN_MONT_CTX_set(mont, n, ctx))
+            && TEST_true(BN_mod_mul_montgomery(c, a, a, mont, ctx))
+            && TEST_true(BN_mod_mul_montgomery(d, a, b, mont, ctx))
+            && TEST_BN_eq(c, d)))
+        goto err;
+
+    /* Regression test for carry bug in bn_sqrx8x_internal */
+    {
+        static const char *ahex[] = {
+                      "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+            "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+            "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+            "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+            "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF8FFEADBCFC4DAE7FFF908E92820306B",
+            "9544D954000000006C0000000000000000000000000000000000000000000000",
+            "00000000000000000000FF030202FFFFF8FFEBDBCFC4DAE7FFF908E92820306B",
+            "9544D954000000006C000000FF0302030000000000FFFFFFFFFFFFFFFFFFFFFF",
+            "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF01FC00FF02FFFFFFFF",
+            "00FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00FCFD",
+            "FCFFFFFFFFFF000000000000000000FF0302030000000000FFFFFFFFFFFFFFFF",
+            "FF00FCFDFDFF030202FF00000000FFFFFFFFFFFFFFFFFF00FCFDFCFFFFFFFFFF",
+            NULL
+        };
+        static const char *nhex[] = {
+                      "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+            "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+            "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+            "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+            "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF8F8F8F8000000",
+            "00000010000000006C0000000000000000000000000000000000000000000000",
+            "00000000000000000000000000000000000000FFFFFFFFFFFFF8F8F8F8000000",
+            "00000010000000006C000000000000000000000000FFFFFFFFFFFFFFFFFFFFFF",
+            "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+            "00FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+            "FFFFFFFFFFFF000000000000000000000000000000000000FFFFFFFFFFFFFFFF",
+            "FFFFFFFFFFFFFFFFFFFF00000000FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
+            NULL
+        };
+
+        if (!(TEST_true(parse_bigBN(&a, ahex))
+                && TEST_true(parse_bigBN(&n, nhex))))
+            goto err;
+    }
+    BN_free(b);
+    if (!(TEST_ptr(b = BN_dup(a))
+            && TEST_true(BN_MONT_CTX_set(mont, n, ctx))))
+        goto err;
+
+    if (!TEST_true(BN_mod_mul_montgomery(c, a, a, mont, ctx))
+            || !TEST_true(BN_mod_mul_montgomery(d, a, b, mont, ctx))
+            || !TEST_BN_eq(c, d))
+        goto err;
+
+    /* Regression test for bug in BN_from_montgomery_word */
+    if (!(TEST_true(BN_hex2bn(&a,
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"))
+         && TEST_true(BN_hex2bn(&n,
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"))
+        && TEST_true(BN_MONT_CTX_set(mont, n, ctx))
+        && TEST_false(BN_mod_mul_montgomery(d, a, a, mont, ctx))))
+        goto err;
+
+    /* Regression test for bug in rsaz_1024_mul_avx2 */
+    if (!(TEST_true(BN_hex2bn(&a,
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF2020202020DF"))
+        && TEST_true(BN_hex2bn(&b,
+        "2020202020202020202020202020202020202020202020202020202020202020"
+        "2020202020202020202020202020202020202020202020202020202020202020"
+        "20202020202020FF202020202020202020202020202020202020202020202020"
+        "2020202020202020202020202020202020202020202020202020202020202020"))
+        && TEST_true(BN_hex2bn(&n,
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF2020202020FF"))
+        && TEST_true(BN_MONT_CTX_set(mont, n, ctx))
+        && TEST_true(BN_mod_exp_mont_consttime(c, a, b, n, ctx, mont))
+        && TEST_true(BN_mod_exp_mont(d, a, b, n, ctx, mont))
+        && TEST_BN_eq(c, d)))
+        goto err;
+
+    /*
+     * rsaz_1024_mul_avx2 expects fully-reduced inputs.
+     * BN_mod_exp_mont_consttime should reduce the input first.
+     */
+    if (!(TEST_true(BN_hex2bn(&a,
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF2020202020DF"))
+        && TEST_true(BN_hex2bn(&b,
+        "1FA53F26F8811C58BE0357897AA5E165693230BC9DF5F01DFA6A2D59229EC69D"
+        "9DE6A89C36E3B6957B22D6FAAD5A3C73AE587B710DBE92E83D3A9A3339A085CB"
+        "B58F508CA4F837924BB52CC1698B7FDC2FD74362456A595A5B58E38E38E38E38"
+        "E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E"))
+        && TEST_true(BN_hex2bn(&n,
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF2020202020DF"))
+        && TEST_true(BN_MONT_CTX_set(mont, n, ctx))
+        && TEST_true(BN_mod_exp_mont_consttime(c, a, b, n, ctx, mont))))
+        goto err;
+    BN_zero(d);
+    if (!TEST_BN_eq(c, d))
+        goto err;
+
+    /*
+     * Regression test for overflow bug in bn_sqr_comba4/8 for
+     * mips-linux-gnu and mipsel-linux-gnu 32bit targets.
+     */
+    {
+        static const char *ehex[] = {
+            "95564994a96c45954227b845a1e99cb939d5a1da99ee91acc962396ae999a9ee",
+            "38603790448f2f7694c242a875f0cad0aae658eba085f312d2febbbd128dd2b5",
+            "8f7d1149f03724215d704344d0d62c587ae3c5939cba4b9b5f3dc5e8e911ef9a",
+            "5ce1a5a749a4989d0d8368f6e1f8cdf3a362a6c97fb02047ff152b480a4ad985",
+            "2d45efdf0770542992afca6a0590d52930434bba96017afbc9f99e112950a8b1",
+            "a359473ec376f329bdae6a19f503be6d4be7393c4e43468831234e27e3838680",
+            "b949390d2e416a3f9759e5349ab4c253f6f29f819a6fe4cbfd27ada34903300e",
+            "da021f62839f5878a36f1bc3085375b00fd5fa3e68d316c0fdace87a97558465",
+            NULL};
+        static const char *phex[] = {
+            "f95dc0f980fbd22e90caa5a387cc4a369f3f830d50dd321c40db8c09a7e1a241",
+            "a536e096622d3280c0c1ba849c1f4a79bf490f60006d081e8cf69960189f0d31",
+            "2cd9e17073a3fba7881b21474a13b334116cb2f5dbf3189a6de3515d0840f053",
+            "c776d3982d391b6d04d642dda5cc6d1640174c09875addb70595658f89efb439",
+            "dc6fbd55f903aadd307982d3f659207f265e1ec6271b274521b7a5e28e8fd7a5",
+            "5df089292820477802a43cf5b6b94e999e8c9944ddebb0d0e95a60f88cb7e813",
+            "ba110d20e1024774107dd02949031864923b3cb8c3f7250d6d1287b0a40db6a4",
+            "7bd5a469518eb65aa207ddc47d8c6e5fc8e0c105be8fc1d4b57b2e27540471d5",
+            NULL};
+        static const char *mhex[] = {
+            "fef15d5ce4625f1bccfbba49fc8439c72bf8202af039a2259678941b60bb4a8f",
+            "2987e965d58fd8cf86a856674d519763d0e1211cc9f8596971050d56d9b35db3",
+            "785866cfbca17cfdbed6060be3629d894f924a89fdc1efc624f80d41a22f1900",
+            "9503fcc3824ef62ccb9208430c26f2d8ceb2c63488ec4c07437aa4c96c43dd8b",
+            "9289ed00a712ff66ee195dc71f5e4ead02172b63c543d69baf495f5fd63ba7bc",
+            "c633bd309c016e37736da92129d0b053d4ab28d21ad7d8b6fab2a8bbdc8ee647",
+            "d2fbcf2cf426cf892e6f5639e0252993965dfb73ccd277407014ea784aaa280c",
+            "b7b03972bc8b0baa72360bdb44b82415b86b2f260f877791cd33ba8f2d65229b",
+            NULL};
+
+        if (!TEST_true(parse_bigBN(&e, ehex))
+                || !TEST_true(parse_bigBN(&p, phex))
+                || !TEST_true(parse_bigBN(&m, mhex))
+                || !TEST_true(BN_mod_exp_mont_consttime(d, e, p, m, ctx, NULL))
+                || !TEST_true(BN_mod_exp_simple(a, e, p, m, ctx))
+                || !TEST_BN_eq(a, d))
+            goto err;
+    }
+
+    /* Zero input */
+    if (!TEST_true(BN_bntest_rand(p, 1024, 0, 0)))
+        goto err;
+    BN_zero(a);
+    if (!TEST_true(BN_mod_exp_mont_consttime(d, a, p, m, ctx, NULL))
+            || !TEST_BN_eq_zero(d))
+        goto err;
+
+    /*
+     * Craft an input whose Montgomery representation is 1, i.e., shorter
+     * than the modulus m, in order to test the const time precomputation
+     * scattering/gathering.
+     */
+    if (!(TEST_true(BN_one(a))
+            && TEST_true(BN_MONT_CTX_set(mont, m, ctx))))
+        goto err;
+    if (!TEST_true(BN_from_montgomery(e, a, mont, ctx))
+            || !TEST_true(BN_mod_exp_mont_consttime(d, e, p, m, ctx, NULL))
+            || !TEST_true(BN_mod_exp_simple(a, e, p, m, ctx))
+            || !TEST_BN_eq(a, d))
+        goto err;
+
+    /* Finally, some regular test vectors. */
+    if (!(TEST_true(BN_bntest_rand(e, 1024, 0, 0))
+            && TEST_true(BN_mod_exp_mont_consttime(d, e, p, m, ctx, NULL))
+            && TEST_true(BN_mod_exp_simple(a, e, p, m, ctx))
+            && TEST_BN_eq(a, d)))
+        goto err;
+
+    st = 1;
+
+ err:
+    BN_MONT_CTX_free(mont);
+    BN_free(a);
+    BN_free(p);
+    BN_free(m);
+    BN_free(d);
+    BN_free(e);
+    BN_free(b);
+    BN_free(n);
+    BN_free(c);
+    return st;
+}
+
+#ifndef OPENSSL_NO_EC2M
+static int test_gf2m_add(void)
+{
+    BIGNUM *a = NULL, *b = NULL, *c = NULL;
+    int i, st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b = BN_new())
+            || !TEST_ptr(c = BN_new()))
+        goto err;
+
+    for (i = 0; i < NUM0; i++) {
+        if (!(TEST_true(BN_rand(a, 512, 0, 0))
+                && TEST_ptr(BN_copy(b, BN_value_one()))))
+            goto err;
+        BN_set_negative(a, rand_neg());
+        BN_set_negative(b, rand_neg());
+        if (!(TEST_true(BN_GF2m_add(c, a, b))
+                /* Test that two added values have the correct parity. */
+                && TEST_false((BN_is_odd(a) && BN_is_odd(c))
+                        || (!BN_is_odd(a) && !BN_is_odd(c)))))
+            goto err;
+        if (!(TEST_true(BN_GF2m_add(c, c, c))
+                /* Test that c + c = 0. */
+                && TEST_BN_eq_zero(c)))
+            goto err;
+    }
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(c);
+    return st;
+}
+
+static int test_gf2m_mod(void)
+{
+    BIGNUM *a = NULL, *b[2] = {NULL,NULL}, *c = NULL, *d = NULL, *e = NULL;
+    int i, j, st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b[0] = BN_new())
+            || !TEST_ptr(b[1] = BN_new())
+            || !TEST_ptr(c = BN_new())
+            || !TEST_ptr(d = BN_new())
+            || !TEST_ptr(e = BN_new()))
+        goto err;
+
+    if (!(TEST_true(BN_GF2m_arr2poly(p0, b[0]))
+            && TEST_true(BN_GF2m_arr2poly(p1, b[1]))))
+        goto err;
+
+    for (i = 0; i < NUM0; i++) {
+        if (!TEST_true(BN_bntest_rand(a, 1024, 0, 0)))
+            goto err;
+        for (j = 0; j < 2; j++) {
+            if (!(TEST_true(BN_GF2m_mod(c, a, b[j]))
+                    && TEST_true(BN_GF2m_add(d, a, c))
+                    && TEST_true(BN_GF2m_mod(e, d, b[j]))
+                    /* Test that a + (a mod p) mod p == 0. */
+                    && TEST_BN_eq_zero(e)))
+                goto err;
+        }
+    }
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b[0]);
+    BN_free(b[1]);
+    BN_free(c);
+    BN_free(d);
+    BN_free(e);
+    return st;
+}
+
+static int test_gf2m_mul(void)
+{
+    BIGNUM *a, *b[2] = {NULL, NULL}, *c = NULL, *d = NULL;
+    BIGNUM *e = NULL, *f = NULL, *g = NULL, *h = NULL;
+    int i, j, st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b[0] = BN_new())
+            || !TEST_ptr(b[1] = BN_new())
+            || !TEST_ptr(c = BN_new())
+            || !TEST_ptr(d = BN_new())
+            || !TEST_ptr(e = BN_new())
+            || !TEST_ptr(f = BN_new())
+            || !TEST_ptr(g = BN_new())
+            || !TEST_ptr(h = BN_new()))
+        goto err;
+
+    if (!(TEST_true(BN_GF2m_arr2poly(p0, b[0]))
+            && TEST_true(BN_GF2m_arr2poly(p1, b[1]))))
+        goto err;
+
+    for (i = 0; i < NUM0; i++) {
+        if (!(TEST_true(BN_bntest_rand(a, 1024, 0, 0))
+                && TEST_true(BN_bntest_rand(c, 1024, 0, 0))
+                && TEST_true(BN_bntest_rand(d, 1024, 0, 0))))
+            goto err;
+        for (j = 0; j < 2; j++) {
+            if (!(TEST_true(BN_GF2m_mod_mul(e, a, c, b[j], ctx))
+                    && TEST_true(BN_GF2m_add(f, a, d))
+                    && TEST_true(BN_GF2m_mod_mul(g, f, c, b[j], ctx))
+                    && TEST_true(BN_GF2m_mod_mul(h, d, c, b[j], ctx))
+                    && TEST_true(BN_GF2m_add(f, e, g))
+                    && TEST_true(BN_GF2m_add(f, f, h))
+                    /* Test that (a+d)*c = a*c + d*c. */
+                    && TEST_BN_eq_zero(f)))
+                goto err;
+        }
+    }
+    st = 1;
+
+ err:
+    BN_free(a);
+    BN_free(b[0]);
+    BN_free(b[1]);
+    BN_free(c);
+    BN_free(d);
+    BN_free(e);
+    BN_free(f);
+    BN_free(g);
+    BN_free(h);
+    return st;
+}
+
+static int test_gf2m_sqr(void)
+{
+    BIGNUM *a = NULL, *b[2] = {NULL,NULL}, *c = NULL, *d = NULL;
+    int i, j, st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b[0] = BN_new())
+            || !TEST_ptr(b[1] = BN_new())
+            || !TEST_ptr(c = BN_new())
+            || !TEST_ptr(d = BN_new()))
+        goto err;
+
+    if (!(TEST_true(BN_GF2m_arr2poly(p0, b[0]))
+            && TEST_true(BN_GF2m_arr2poly(p1, b[1]))))
+        goto err;
+
+    for (i = 0; i < NUM0; i++) {
+        if (!TEST_true(BN_bntest_rand(a, 1024, 0, 0)))
+                goto err;
+        for (j = 0; j < 2; j++) {
+            if (!(TEST_true(BN_GF2m_mod_sqr(c, a, b[j], ctx))
+                    && TEST_true(BN_copy(d, a))
+                    && TEST_true(BN_GF2m_mod_mul(d, a, d, b[j], ctx))
+                    && TEST_true(BN_GF2m_add(d, c, d))
+                    /* Test that a*a = a^2. */
+                    && TEST_BN_eq_zero(d)))
+                goto err;
+        }
+    }
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b[0]);
+    BN_free(b[1]);
+    BN_free(c);
+    BN_free(d);
+    return st;
+}
+
+static int test_gf2m_modinv(void)
+{
+    BIGNUM *a = NULL, *b[2] = {NULL,NULL}, *c = NULL, *d = NULL;
+    int i, j, st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b[0] = BN_new())
+            || !TEST_ptr(b[1] = BN_new())
+            || !TEST_ptr(c = BN_new())
+            || !TEST_ptr(d = BN_new()))
+        goto err;
+
+    if (!(TEST_true(BN_GF2m_arr2poly(p0, b[0]))
+            && TEST_true(BN_GF2m_arr2poly(p1, b[1]))))
+        goto err;
+
+    for (i = 0; i < NUM0; i++) {
+        if (!TEST_true(BN_bntest_rand(a, 512, 0, 0)))
+            goto err;
+        for (j = 0; j < 2; j++) {
+            if (!(TEST_true(BN_GF2m_mod_inv(c, a, b[j], ctx))
+                    && TEST_true(BN_GF2m_mod_mul(d, a, c, b[j], ctx))
+                    /* Test that ((1/a)*a) = 1. */
+                    && TEST_BN_eq_one(d)))
+                goto err;
+        }
+    }
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b[0]);
+    BN_free(b[1]);
+    BN_free(c);
+    BN_free(d);
+    return st;
+}
+
+static int test_gf2m_moddiv(void)
+{
+    BIGNUM *a = NULL, *b[2] = {NULL,NULL}, *c = NULL, *d = NULL;
+    BIGNUM *e = NULL, *f = NULL;
+    int i, j, st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b[0] = BN_new())
+            || !TEST_ptr(b[1] = BN_new())
+            || !TEST_ptr(c = BN_new())
+            || !TEST_ptr(d = BN_new())
+            || !TEST_ptr(e = BN_new())
+            || !TEST_ptr(f = BN_new()))
+        goto err;
+
+    if (!(TEST_true(BN_GF2m_arr2poly(p0, b[0]))
+            && TEST_true(BN_GF2m_arr2poly(p1, b[1]))))
+        goto err;
+
+    for (i = 0; i < NUM0; i++) {
+        if (!(TEST_true(BN_bntest_rand(a, 512, 0, 0))
+                && TEST_true(BN_bntest_rand(c, 512, 0, 0))))
+            goto err;
+        for (j = 0; j < 2; j++) {
+            if (!(TEST_true(BN_GF2m_mod_div(d, a, c, b[j], ctx))
+                    && TEST_true(BN_GF2m_mod_mul(e, d, c, b[j], ctx))
+                    && TEST_true(BN_GF2m_mod_div(f, a, e, b[j], ctx))
+                    /* Test that ((a/c)*c)/a = 1. */
+                    && TEST_BN_eq_one(f)))
+                goto err;
+        }
+    }
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b[0]);
+    BN_free(b[1]);
+    BN_free(c);
+    BN_free(d);
+    BN_free(e);
+    BN_free(f);
+    return st;
+}
+
+static int test_gf2m_modexp(void)
+{
+    BIGNUM *a = NULL, *b[2] = {NULL,NULL}, *c = NULL, *d = NULL;
+    BIGNUM *e = NULL, *f = NULL;
+    int i, j, st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b[0] = BN_new())
+            || !TEST_ptr(b[1] = BN_new())
+            || !TEST_ptr(c = BN_new())
+            || !TEST_ptr(d = BN_new())
+            || !TEST_ptr(e = BN_new())
+            || !TEST_ptr(f = BN_new()))
+        goto err;
+
+    if (!(TEST_true(BN_GF2m_arr2poly(p0, b[0]))
+            && TEST_true(BN_GF2m_arr2poly(p1, b[1]))))
+        goto err;
+
+    for (i = 0; i < NUM0; i++) {
+        if (!(TEST_true(BN_bntest_rand(a, 512, 0, 0))
+                && TEST_true(BN_bntest_rand(c, 512, 0, 0))
+                && TEST_true(BN_bntest_rand(d, 512, 0, 0))))
+            goto err;
+        for (j = 0; j < 2; j++) {
+            if (!(TEST_true(BN_GF2m_mod_exp(e, a, c, b[j], ctx))
+                    && TEST_true(BN_GF2m_mod_exp(f, a, d, b[j], ctx))
+                    && TEST_true(BN_GF2m_mod_mul(e, e, f, b[j], ctx))
+                    && TEST_true(BN_add(f, c, d))
+                    && TEST_true(BN_GF2m_mod_exp(f, a, f, b[j], ctx))
+                    && TEST_true(BN_GF2m_add(f, e, f))
+                    /* Test that a^(c+d)=a^c*a^d. */
+                    && TEST_BN_eq_zero(f)))
+                goto err;
+        }
+    }
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b[0]);
+    BN_free(b[1]);
+    BN_free(c);
+    BN_free(d);
+    BN_free(e);
+    BN_free(f);
+    return st;
+}
+
+static int test_gf2m_modsqrt(void)
+{
+    BIGNUM *a = NULL, *b[2] = {NULL,NULL}, *c = NULL, *d = NULL;
+    BIGNUM *e = NULL, *f = NULL;
+    int i, j, st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b[0] = BN_new())
+            || !TEST_ptr(b[1] = BN_new())
+            || !TEST_ptr(c = BN_new())
+            || !TEST_ptr(d = BN_new())
+            || !TEST_ptr(e = BN_new())
+            || !TEST_ptr(f = BN_new()))
+        goto err;
+
+    if (!(TEST_true(BN_GF2m_arr2poly(p0, b[0]))
+            && TEST_true(BN_GF2m_arr2poly(p1, b[1]))))
+        goto err;
+
+    for (i = 0; i < NUM0; i++) {
+        if (!TEST_true(BN_bntest_rand(a, 512, 0, 0)))
+            goto err;
+
+        for (j = 0; j < 2; j++) {
+            if (!(TEST_true(BN_GF2m_mod(c, a, b[j]))
+                    && TEST_true(BN_GF2m_mod_sqrt(d, a, b[j], ctx))
+                    && TEST_true(BN_GF2m_mod_sqr(e, d, b[j], ctx))
+                    && TEST_true(BN_GF2m_add(f, c, e))
+                    /* Test that d^2 = a, where d = sqrt(a). */
+                    && TEST_BN_eq_zero(f)))
+                goto err;
+        }
+    }
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b[0]);
+    BN_free(b[1]);
+    BN_free(c);
+    BN_free(d);
+    BN_free(e);
+    BN_free(f);
+    return st;
+}
+
+static int test_gf2m_modsolvequad(void)
+{
+    BIGNUM *a = NULL, *b[2] = {NULL,NULL}, *c = NULL, *d = NULL;
+    BIGNUM *e = NULL;
+    int i, j, s = 0, t, st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b[0] = BN_new())
+            || !TEST_ptr(b[1] = BN_new())
+            || !TEST_ptr(c = BN_new())
+            || !TEST_ptr(d = BN_new())
+            || !TEST_ptr(e = BN_new()))
+        goto err;
+
+    if (!(TEST_true(BN_GF2m_arr2poly(p0, b[0]))
+            && TEST_true(BN_GF2m_arr2poly(p1, b[1]))))
+        goto err;
+
+    for (i = 0; i < NUM0; i++) {
+        if (!TEST_true(BN_bntest_rand(a, 512, 0, 0)))
+            goto err;
+        for (j = 0; j < 2; j++) {
+            t = BN_GF2m_mod_solve_quad(c, a, b[j], ctx);
+            if (t) {
+                s++;
+                if (!(TEST_true(BN_GF2m_mod_sqr(d, c, b[j], ctx))
+                        && TEST_true(BN_GF2m_add(d, c, d))
+                        && TEST_true(BN_GF2m_mod(e, a, b[j]))
+                        && TEST_true(BN_GF2m_add(e, e, d))
+                        /*
+                         * Test that solution of quadratic c
+                         * satisfies c^2 + c = a.
+                         */
+                        && TEST_BN_eq_zero(e)))
+                    goto err;
+            }
+        }
+    }
+    if (!TEST_int_ge(s, 0)) {
+        TEST_info("%d tests found no roots; probably an error", NUM0);
+        goto err;
+    }
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b[0]);
+    BN_free(b[1]);
+    BN_free(c);
+    BN_free(d);
+    BN_free(e);
+    return st;
+}
+#endif
+
+static int test_kronecker(void)
+{
+    BIGNUM *a = NULL, *b = NULL, *r = NULL, *t = NULL;
+    int i, legendre, kronecker, st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b = BN_new())
+            || !TEST_ptr(r = BN_new())
+            || !TEST_ptr(t = BN_new()))
+        goto err;
+
+    /*
+     * We test BN_kronecker(a, b, ctx) just for b odd (Jacobi symbol). In
+     * this case we know that if b is prime, then BN_kronecker(a, b, ctx) is
+     * congruent to $a^{(b-1)/2}$, modulo $b$ (Legendre symbol). So we
+     * generate a random prime b and compare these values for a number of
+     * random a's.  (That is, we run the Solovay-Strassen primality test to
+     * confirm that b is prime, except that we don't want to test whether b
+     * is prime but whether BN_kronecker works.)
+     */
+
+    if (!TEST_true(BN_generate_prime_ex(b, 512, 0, NULL, NULL, NULL)))
+        goto err;
+    BN_set_negative(b, rand_neg());
+
+    for (i = 0; i < NUM0; i++) {
+        if (!TEST_true(BN_bntest_rand(a, 512, 0, 0)))
+            goto err;
+        BN_set_negative(a, rand_neg());
+
+        /* t := (|b|-1)/2  (note that b is odd) */
+        if (!TEST_true(BN_copy(t, b)))
+            goto err;
+        BN_set_negative(t, 0);
+        if (!TEST_true(BN_sub_word(t, 1)))
+            goto err;
+        if (!TEST_true(BN_rshift1(t, t)))
+            goto err;
+        /* r := a^t mod b */
+        BN_set_negative(b, 0);
+
+        if (!TEST_true(BN_mod_exp_recp(r, a, t, b, ctx)))
+            goto err;
+        BN_set_negative(b, 1);
+
+        if (BN_is_word(r, 1))
+            legendre = 1;
+        else if (BN_is_zero(r))
+            legendre = 0;
+        else {
+            if (!TEST_true(BN_add_word(r, 1)))
+                goto err;
+            if (!TEST_int_eq(BN_ucmp(r, b), 0)) {
+                TEST_info("Legendre symbol computation failed");
+                goto err;
+            }
+            legendre = -1;
+        }
+
+        if (!TEST_int_ge(kronecker = BN_kronecker(a, b, ctx), -1))
+            goto err;
+        /* we actually need BN_kronecker(a, |b|) */
+        if (BN_is_negative(a) && BN_is_negative(b))
+            kronecker = -kronecker;
+
+        if (!TEST_int_eq(legendre, kronecker))
+            goto err;
+    }
+
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(r);
+    BN_free(t);
+    return st;
+}
+
+static int file_sum(STANZA *s)
+{
+    BIGNUM *a = NULL, *b = NULL, *sum = NULL, *ret = NULL;
+    BN_ULONG b_word;
+    int st = 0;
+
+    if (!TEST_ptr(a = getBN(s, "A"))
+            || !TEST_ptr(b = getBN(s, "B"))
+            || !TEST_ptr(sum = getBN(s, "Sum"))
+            || !TEST_ptr(ret = BN_new()))
+        goto err;
+
+    if (!TEST_true(BN_add(ret, a, b))
+            || !equalBN("A + B", sum, ret)
+            || !TEST_true(BN_sub(ret, sum, a))
+            || !equalBN("Sum - A", b, ret)
+            || !TEST_true(BN_sub(ret, sum, b))
+            || !equalBN("Sum - B", a, ret))
+        goto err;
+
+    /*
+     * Test that the functions work when |r| and |a| point to the same BIGNUM,
+     * or when |r| and |b| point to the same BIGNUM.
+     * TODO: Test where all of |r|, |a|, and |b| point to the same BIGNUM.
+     */
+    if (!TEST_true(BN_copy(ret, a))
+            || !TEST_true(BN_add(ret, ret, b))
+            || !equalBN("A + B (r is a)", sum, ret)
+            || !TEST_true(BN_copy(ret, b))
+            || !TEST_true(BN_add(ret, a, ret))
+            || !equalBN("A + B (r is b)", sum, ret)
+            || !TEST_true(BN_copy(ret, sum))
+            || !TEST_true(BN_sub(ret, ret, a))
+            || !equalBN("Sum - A (r is a)", b, ret)
+            || !TEST_true(BN_copy(ret, a))
+            || !TEST_true(BN_sub(ret, sum, ret))
+            || !equalBN("Sum - A (r is b)", b, ret)
+            || !TEST_true(BN_copy(ret, sum))
+            || !TEST_true(BN_sub(ret, ret, b))
+            || !equalBN("Sum - B (r is a)", a, ret)
+            || !TEST_true(BN_copy(ret, b))
+            || !TEST_true(BN_sub(ret, sum, ret))
+            || !equalBN("Sum - B (r is b)", a, ret))
+        goto err;
+
+    /*
+     * Test BN_uadd() and BN_usub() with the prerequisites they are
+     * documented as having. Note that these functions are frequently used
+     * when the prerequisites don't hold. In those cases, they are supposed
+     * to work as if the prerequisite hold, but we don't test that yet.
+     * TODO: test that.
+     */
+    if (!BN_is_negative(a) && !BN_is_negative(b) && BN_cmp(a, b) >= 0) {
+        if (!TEST_true(BN_uadd(ret, a, b))
+                || !equalBN("A +u B", sum, ret)
+                || !TEST_true(BN_usub(ret, sum, a))
+                || !equalBN("Sum -u A", b, ret)
+                || !TEST_true(BN_usub(ret, sum, b))
+                || !equalBN("Sum -u B", a, ret))
+            goto err;
+        /*
+         * Test that the functions work when |r| and |a| point to the same
+         * BIGNUM, or when |r| and |b| point to the same BIGNUM.
+         * TODO: Test where all of |r|, |a|, and |b| point to the same BIGNUM.
+         */
+        if (!TEST_true(BN_copy(ret, a))
+                || !TEST_true(BN_uadd(ret, ret, b))
+                || !equalBN("A +u B (r is a)", sum, ret)
+                || !TEST_true(BN_copy(ret, b))
+                || !TEST_true(BN_uadd(ret, a, ret))
+                || !equalBN("A +u B (r is b)", sum, ret)
+                || !TEST_true(BN_copy(ret, sum))
+                || !TEST_true(BN_usub(ret, ret, a))
+                || !equalBN("Sum -u A (r is a)", b, ret)
+                || !TEST_true(BN_copy(ret, a))
+                || !TEST_true(BN_usub(ret, sum, ret))
+                || !equalBN("Sum -u A (r is b)", b, ret)
+                || !TEST_true(BN_copy(ret, sum))
+                || !TEST_true(BN_usub(ret, ret, b))
+                || !equalBN("Sum -u B (r is a)", a, ret)
+                || !TEST_true(BN_copy(ret, b))
+                || !TEST_true(BN_usub(ret, sum, ret))
+                || !equalBN("Sum -u B (r is b)", a, ret))
+            goto err;
+    }
+
+    /*
+     * Test with BN_add_word() and BN_sub_word() if |b| is small enough.
+     */
+    b_word = BN_get_word(b);
+    if (!BN_is_negative(b) && b_word != (BN_ULONG)-1) {
+        if (!TEST_true(BN_copy(ret, a))
+                || !TEST_true(BN_add_word(ret, b_word))
+                || !equalBN("A + B (word)", sum, ret)
+                || !TEST_true(BN_copy(ret, sum))
+                || !TEST_true(BN_sub_word(ret, b_word))
+                || !equalBN("Sum - B (word)", a, ret))
+            goto err;
+    }
+    st = 1;
+
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(sum);
+    BN_free(ret);
+    return st;
+}
+
+static int file_lshift1(STANZA *s)
+{
+    BIGNUM *a = NULL, *lshift1 = NULL, *zero = NULL, *ret = NULL;
+    BIGNUM *two = NULL, *remainder = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(a = getBN(s, "A"))
+            || !TEST_ptr(lshift1 = getBN(s, "LShift1"))
+            || !TEST_ptr(zero = BN_new())
+            || !TEST_ptr(ret = BN_new())
+            || !TEST_ptr(two = BN_new())
+            || !TEST_ptr(remainder = BN_new()))
+        goto err;
+
+    BN_zero(zero);
+
+    if (!TEST_true(BN_set_word(two, 2))
+            || !TEST_true(BN_add(ret, a, a))
+            || !equalBN("A + A", lshift1, ret)
+            || !TEST_true(BN_mul(ret, a, two, ctx))
+            || !equalBN("A * 2", lshift1, ret)
+            || !TEST_true(BN_div(ret, remainder, lshift1, two, ctx))
+            || !equalBN("LShift1 / 2", a, ret)
+            || !equalBN("LShift1 % 2", zero, remainder)
+            || !TEST_true(BN_lshift1(ret, a))
+            || !equalBN("A << 1", lshift1, ret)
+            || !TEST_true(BN_rshift1(ret, lshift1))
+            || !equalBN("LShift >> 1", a, ret)
+            || !TEST_true(BN_rshift1(ret, lshift1))
+            || !equalBN("LShift >> 1", a, ret))
+        goto err;
+
+    /* Set the LSB to 1 and test rshift1 again. */
+    if (!TEST_true(BN_set_bit(lshift1, 0))
+            || !TEST_true(BN_div(ret, NULL /* rem */ , lshift1, two, ctx))
+            || !equalBN("(LShift1 | 1) / 2", a, ret)
+            || !TEST_true(BN_rshift1(ret, lshift1))
+            || !equalBN("(LShift | 1) >> 1", a, ret))
+        goto err;
+
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(lshift1);
+    BN_free(zero);
+    BN_free(ret);
+    BN_free(two);
+    BN_free(remainder);
+
+    return st;
+}
+
+static int file_lshift(STANZA *s)
+{
+    BIGNUM *a = NULL, *lshift = NULL, *ret = NULL;
+    int n = 0, st = 0;
+
+    if (!TEST_ptr(a = getBN(s, "A"))
+            || !TEST_ptr(lshift = getBN(s, "LShift"))
+            || !TEST_ptr(ret = BN_new())
+            || !getint(s, &n, "N"))
+        goto err;
+
+    if (!TEST_true(BN_lshift(ret, a, n))
+            || !equalBN("A << N", lshift, ret)
+            || !TEST_true(BN_rshift(ret, lshift, n))
+            || !equalBN("A >> N", a, ret))
+        goto err;
+
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(lshift);
+    BN_free(ret);
+    return st;
+}
+
+static int file_rshift(STANZA *s)
+{
+    BIGNUM *a = NULL, *rshift = NULL, *ret = NULL;
+    int n = 0, st = 0;
+
+    if (!TEST_ptr(a = getBN(s, "A"))
+            || !TEST_ptr(rshift = getBN(s, "RShift"))
+            || !TEST_ptr(ret = BN_new())
+            || !getint(s, &n, "N"))
+        goto err;
+
+    if (!TEST_true(BN_rshift(ret, a, n))
+            || !equalBN("A >> N", rshift, ret))
+        goto err;
+
+    /* If N == 1, try with rshift1 as well */
+    if (n == 1) {
+        if (!TEST_true(BN_rshift1(ret, a))
+                || !equalBN("A >> 1 (rshift1)", rshift, ret))
+            goto err;
+    }
+    st = 1;
+
+ err:
+    BN_free(a);
+    BN_free(rshift);
+    BN_free(ret);
+    return st;
+}
+
+static int file_square(STANZA *s)
+{
+    BIGNUM *a = NULL, *square = NULL, *zero = NULL, *ret = NULL;
+    BIGNUM *remainder = NULL, *tmp = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(a = getBN(s, "A"))
+            || !TEST_ptr(square = getBN(s, "Square"))
+            || !TEST_ptr(zero = BN_new())
+            || !TEST_ptr(ret = BN_new())
+            || !TEST_ptr(remainder = BN_new()))
+        goto err;
+
+    BN_zero(zero);
+    if (!TEST_true(BN_sqr(ret, a, ctx))
+            || !equalBN("A^2", square, ret)
+            || !TEST_true(BN_mul(ret, a, a, ctx))
+            || !equalBN("A * A", square, ret)
+            || !TEST_true(BN_div(ret, remainder, square, a, ctx))
+            || !equalBN("Square / A", a, ret)
+            || !equalBN("Square % A", zero, remainder))
+        goto err;
+
+#if HAVE_BN_SQRT
+    BN_set_negative(a, 0);
+    if (!TEST_true(BN_sqrt(ret, square, ctx))
+            || !equalBN("sqrt(Square)", a, ret))
+        goto err;
+
+    /* BN_sqrt should fail on non-squares and negative numbers. */
+    if (!TEST_BN_eq_zero(square)) {
+        if (!TEST_ptr(tmp = BN_new())
+                || !TEST_true(BN_copy(tmp, square)))
+            goto err;
+        BN_set_negative(tmp, 1);
+
+        if (!TEST_int_eq(BN_sqrt(ret, tmp, ctx), 0))
+            goto err;
+        ERR_clear_error();
+
+        BN_set_negative(tmp, 0);
+        if (BN_add(tmp, tmp, BN_value_one()))
+            goto err;
+        if (!TEST_int_eq(BN_sqrt(ret, tmp, ctx)))
+            goto err;
+        ERR_clear_error();
+    }
+#endif
+
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(square);
+    BN_free(zero);
+    BN_free(ret);
+    BN_free(remainder);
+    BN_free(tmp);
+    return st;
+}
+
+static int file_product(STANZA *s)
+{
+    BIGNUM *a = NULL, *b = NULL, *product = NULL, *ret = NULL;
+    BIGNUM *remainder = NULL, *zero = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(a = getBN(s, "A"))
+            || !TEST_ptr(b = getBN(s, "B"))
+            || !TEST_ptr(product = getBN(s, "Product"))
+            || !TEST_ptr(ret = BN_new())
+            || !TEST_ptr(remainder = BN_new())
+            || !TEST_ptr(zero = BN_new()))
+        goto err;
+
+    BN_zero(zero);
+
+    if (!TEST_true(BN_mul(ret, a, b, ctx))
+            || !equalBN("A * B", product, ret)
+            || !TEST_true(BN_div(ret, remainder, product, a, ctx))
+            || !equalBN("Product / A", b, ret)
+            || !equalBN("Product % A", zero, remainder)
+            || !TEST_true(BN_div(ret, remainder, product, b, ctx))
+            || !equalBN("Product / B", a, ret)
+            || !equalBN("Product % B", zero, remainder))
+        goto err;
+
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(product);
+    BN_free(ret);
+    BN_free(remainder);
+    BN_free(zero);
+    return st;
+}
+
+static int file_quotient(STANZA *s)
+{
+    BIGNUM *a = NULL, *b = NULL, *quotient = NULL, *remainder = NULL;
+    BIGNUM *ret = NULL, *ret2 = NULL, *nnmod = NULL;
+    BN_ULONG b_word, ret_word;
+    int st = 0;
+
+    if (!TEST_ptr(a = getBN(s, "A"))
+            || !TEST_ptr(b = getBN(s, "B"))
+            || !TEST_ptr(quotient = getBN(s, "Quotient"))
+            || !TEST_ptr(remainder = getBN(s, "Remainder"))
+            || !TEST_ptr(ret = BN_new())
+            || !TEST_ptr(ret2 = BN_new())
+            || !TEST_ptr(nnmod = BN_new()))
+        goto err;
+
+    if (!TEST_true(BN_div(ret, ret2, a, b, ctx))
+            || !equalBN("A / B", quotient, ret)
+            || !equalBN("A % B", remainder, ret2)
+            || !TEST_true(BN_mul(ret, quotient, b, ctx))
+            || !TEST_true(BN_add(ret, ret, remainder))
+            || !equalBN("Quotient * B + Remainder", a, ret))
+        goto err;
+
+    /*
+     * Test with BN_mod_word() and BN_div_word() if the divisor is
+     * small enough.
+     */
+    b_word = BN_get_word(b);
+    if (!BN_is_negative(b) && b_word != (BN_ULONG)-1) {
+        BN_ULONG remainder_word = BN_get_word(remainder);
+
+        assert(remainder_word != (BN_ULONG)-1);
+        if (!TEST_ptr(BN_copy(ret, a)))
+            goto err;
+        ret_word = BN_div_word(ret, b_word);
+        if (ret_word != remainder_word) {
+#ifdef BN_DEC_FMT1
+            TEST_error(
+                    "Got A %% B (word) = " BN_DEC_FMT1 ", wanted " BN_DEC_FMT1,
+                    ret_word, remainder_word);
+#else
+            TEST_error("Got A %% B (word) mismatch");
+#endif
+            goto err;
+        }
+        if (!equalBN ("A / B (word)", quotient, ret))
+            goto err;
+
+        ret_word = BN_mod_word(a, b_word);
+        if (ret_word != remainder_word) {
+#ifdef BN_DEC_FMT1
+            TEST_error(
+                    "Got A %% B (word) = " BN_DEC_FMT1 ", wanted " BN_DEC_FMT1 "",
+                    ret_word, remainder_word);
+#else
+            TEST_error("Got A %% B (word) mismatch");
+#endif
+            goto err;
+        }
+    }
+
+    /* Test BN_nnmod. */
+    if (!BN_is_negative(b)) {
+        if (!TEST_true(BN_copy(nnmod, remainder))
+                || (BN_is_negative(nnmod)
+                        && !TEST_true(BN_add(nnmod, nnmod, b)))
+                || !TEST_true(BN_nnmod(ret, a, b, ctx))
+                || !equalBN("A % B (non-negative)", nnmod, ret))
+            goto err;
+    }
+
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(quotient);
+    BN_free(remainder);
+    BN_free(ret);
+    BN_free(ret2);
+    BN_free(nnmod);
+    return st;
+}
+
+static int file_modmul(STANZA *s)
+{
+    BIGNUM *a = NULL, *b = NULL, *m = NULL, *mod_mul = NULL, *ret = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(a = getBN(s, "A"))
+            || !TEST_ptr(b = getBN(s, "B"))
+            || !TEST_ptr(m = getBN(s, "M"))
+            || !TEST_ptr(mod_mul = getBN(s, "ModMul"))
+            || !TEST_ptr(ret = BN_new()))
+        goto err;
+
+    if (!TEST_true(BN_mod_mul(ret, a, b, m, ctx))
+            || !equalBN("A * B (mod M)", mod_mul, ret))
+        goto err;
+
+    if (BN_is_odd(m)) {
+        /* Reduce |a| and |b| and test the Montgomery version. */
+        BN_MONT_CTX *mont = BN_MONT_CTX_new();
+        BIGNUM *a_tmp = BN_new();
+        BIGNUM *b_tmp = BN_new();
+
+        if (mont == NULL || a_tmp == NULL || b_tmp == NULL
+                || !TEST_true(BN_MONT_CTX_set(mont, m, ctx))
+                || !TEST_true(BN_nnmod(a_tmp, a, m, ctx))
+                || !TEST_true(BN_nnmod(b_tmp, b, m, ctx))
+                || !TEST_true(BN_to_montgomery(a_tmp, a_tmp, mont, ctx))
+                || !TEST_true(BN_to_montgomery(b_tmp, b_tmp, mont, ctx))
+                || !TEST_true(BN_mod_mul_montgomery(ret, a_tmp, b_tmp,
+                                                    mont, ctx))
+                || !TEST_true(BN_from_montgomery(ret, ret, mont, ctx))
+                || !equalBN("A * B (mod M) (mont)", mod_mul, ret))
+            st = 0;
+        else
+            st = 1;
+        BN_MONT_CTX_free(mont);
+        BN_free(a_tmp);
+        BN_free(b_tmp);
+        if (st == 0)
+            goto err;
+    }
+
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(m);
+    BN_free(mod_mul);
+    BN_free(ret);
+    return st;
+}
+
+static int file_modexp(STANZA *s)
+{
+    BIGNUM *a = NULL, *e = NULL, *m = NULL, *mod_exp = NULL, *ret = NULL;
+    BIGNUM *b = NULL, *c = NULL, *d = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(a = getBN(s, "A"))
+            || !TEST_ptr(e = getBN(s, "E"))
+            || !TEST_ptr(m = getBN(s, "M"))
+            || !TEST_ptr(mod_exp = getBN(s, "ModExp"))
+            || !TEST_ptr(ret = BN_new())
+            || !TEST_ptr(d = BN_new()))
+        goto err;
+
+    if (!TEST_true(BN_mod_exp(ret, a, e, m, ctx))
+            || !equalBN("A ^ E (mod M)", mod_exp, ret))
+        goto err;
+
+    if (BN_is_odd(m)) {
+        if (!TEST_true(BN_mod_exp_mont(ret, a, e, m, ctx, NULL))
+                || !equalBN("A ^ E (mod M) (mont)", mod_exp, ret)
+                || !TEST_true(BN_mod_exp_mont_consttime(ret, a, e, m,
+                                                        ctx, NULL))
+                || !equalBN("A ^ E (mod M) (mont const", mod_exp, ret))
+            goto err;
+    }
+
+    /* Regression test for carry propagation bug in sqr8x_reduction */
+    BN_hex2bn(&a, "050505050505");
+    BN_hex2bn(&b, "02");
+    BN_hex2bn(&c,
+        "4141414141414141414141274141414141414141414141414141414141414141"
+        "4141414141414141414141414141414141414141414141414141414141414141"
+        "4141414141414141414141800000000000000000000000000000000000000000"
+        "0000000000000000000000000000000000000000000000000000000000000000"
+        "0000000000000000000000000000000000000000000000000000000000000000"
+        "0000000000000000000000000000000000000000000000000000000001");
+    if (!TEST_true(BN_mod_exp(d, a, b, c, ctx))
+        || !TEST_true(BN_mul(e, a, a, ctx))
+        || !TEST_BN_eq(d, e))
+        goto err;
+
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(c);
+    BN_free(d);
+    BN_free(e);
+    BN_free(m);
+    BN_free(mod_exp);
+    BN_free(ret);
+    return st;
+}
+
+static int file_exp(STANZA *s)
+{
+    BIGNUM *a = NULL, *e = NULL, *exp = NULL, *ret = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(a = getBN(s, "A"))
+            || !TEST_ptr(e = getBN(s, "E"))
+            || !TEST_ptr(exp = getBN(s, "Exp"))
+            || !TEST_ptr(ret = BN_new()))
+        goto err;
+
+    if (!TEST_true(BN_exp(ret, a, e, ctx))
+            || !equalBN("A ^ E", exp, ret))
+        goto err;
+
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(e);
+    BN_free(exp);
+    BN_free(ret);
+    return st;
+}
+
+static int file_modsqrt(STANZA *s)
+{
+    BIGNUM *a = NULL, *p = NULL, *mod_sqrt = NULL, *ret = NULL, *ret2 = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(a = getBN(s, "A"))
+            || !TEST_ptr(p = getBN(s, "P"))
+            || !TEST_ptr(mod_sqrt = getBN(s, "ModSqrt"))
+            || !TEST_ptr(ret = BN_new())
+            || !TEST_ptr(ret2 = BN_new()))
+        goto err;
+
+    if (BN_is_negative(mod_sqrt)) {
+        /* A negative testcase */
+        if (!TEST_ptr_null(BN_mod_sqrt(ret, a, p, ctx)))
+            goto err;
+
+        st = 1;
+        goto err;
+    }
+
+    /* There are two possible answers. */
+    if (!TEST_ptr(BN_mod_sqrt(ret, a, p, ctx))
+            || !TEST_true(BN_sub(ret2, p, ret)))
+        goto err;
+
+    /* The first condition should NOT be a test. */
+    if (BN_cmp(ret2, mod_sqrt) != 0
+            && !equalBN("sqrt(A) (mod P)", mod_sqrt, ret))
+        goto err;
+
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(p);
+    BN_free(mod_sqrt);
+    BN_free(ret);
+    BN_free(ret2);
+    return st;
+}
+
+static int file_gcd(STANZA *s)
+{
+    BIGNUM *a = NULL, *b = NULL, *gcd = NULL, *ret = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(a = getBN(s, "A"))
+            || !TEST_ptr(b = getBN(s, "B"))
+            || !TEST_ptr(gcd = getBN(s, "GCD"))
+            || !TEST_ptr(ret = BN_new()))
+        goto err;
+
+    if (!TEST_true(BN_gcd(ret, a, b, ctx))
+            || !equalBN("gcd(A,B)", gcd, ret))
+        goto err;
+
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(gcd);
+    BN_free(ret);
+    return st;
+}
+
+static int test_bn2padded(void)
+{
+    uint8_t zeros[256], out[256], reference[128];
+    size_t bytes;
+    BIGNUM *n;
+    int st = 0;
+
+    /* Test edge case at 0. */
+    if (!TEST_ptr((n = BN_new())))
+        goto err;
+    if (!TEST_int_eq(BN_bn2binpad(n, NULL, 0), 0))
+        goto err;
+    memset(out, -1, sizeof(out));
+    if (!TEST_int_eq(BN_bn2binpad(n, out, sizeof(out)), sizeof(out)))
+        goto err;
+    memset(zeros, 0, sizeof(zeros));
+    if (!TEST_mem_eq(zeros, sizeof(zeros), out, sizeof(out)))
+        goto err;
+
+    /* Test a random numbers at various byte lengths. */
+    for (bytes = 128 - 7; bytes <= 128; bytes++) {
+# define TOP_BIT_ON 0
+# define BOTTOM_BIT_NOTOUCH 0
+        if (!TEST_true(BN_rand(n, bytes * 8, TOP_BIT_ON, BOTTOM_BIT_NOTOUCH)))
+            goto err;
+        if (!TEST_int_eq(BN_num_bytes(n), bytes)
+                || !TEST_int_eq(BN_bn2bin(n, reference), bytes))
+            goto err;
+        /* Empty buffer should fail. */
+        if (!TEST_int_eq(BN_bn2binpad(n, NULL, 0), -1))
+            goto err;
+        /* One byte short should fail. */
+        if (!TEST_int_eq(BN_bn2binpad(n, out, bytes - 1), -1))
+            goto err;
+        /* Exactly right size should encode. */
+        if (!TEST_int_eq(BN_bn2binpad(n, out, bytes), bytes)
+                || !TEST_mem_eq(out, bytes, reference, bytes))
+            goto err;
+        /* Pad up one byte extra. */
+        if (!TEST_int_eq(BN_bn2binpad(n, out, bytes + 1), bytes + 1)
+                || !TEST_mem_eq(out + 1, bytes, reference, bytes)
+                || !TEST_mem_eq(out, 1, zeros, 1))
+            goto err;
+        /* Pad up to 256. */
+        if (!TEST_int_eq(BN_bn2binpad(n, out, sizeof(out)), sizeof(out))
+                || !TEST_mem_eq(out + sizeof(out) - bytes, bytes,
+                                reference, bytes)
+                || !TEST_mem_eq(out, sizeof(out) - bytes,
+                                zeros, sizeof(out) - bytes))
+            goto err;
+    }
+
+    st = 1;
+ err:
+    BN_free(n);
+    return st;
+}
+
+static int test_dec2bn(void)
+{
+    BIGNUM *bn = NULL;
+    int st = 0;
+
+    if (!TEST_int_eq(parsedecBN(&bn, "0"), 1)
+            || !TEST_BN_eq_word(bn, 0)
+            || !TEST_BN_eq_zero(bn)
+            || !TEST_BN_le_zero(bn)
+            || !TEST_BN_ge_zero(bn)
+            || !TEST_BN_even(bn))
+        goto err;
+    BN_free(bn);
+    bn = NULL;
+
+    if (!TEST_int_eq(parsedecBN(&bn, "256"), 3)
+            || !TEST_BN_eq_word(bn, 256)
+            || !TEST_BN_ge_zero(bn)
+            || !TEST_BN_gt_zero(bn)
+            || !TEST_BN_ne_zero(bn)
+            || !TEST_BN_even(bn))
+        goto err;
+    BN_free(bn);
+    bn = NULL;
+
+    if (!TEST_int_eq(parsedecBN(&bn, "-42"), 3)
+            || !TEST_BN_abs_eq_word(bn, 42)
+            || !TEST_BN_lt_zero(bn)
+            || !TEST_BN_le_zero(bn)
+            || !TEST_BN_ne_zero(bn)
+            || !TEST_BN_even(bn))
+        goto err;
+    BN_free(bn);
+    bn = NULL;
+
+    if (!TEST_int_eq(parsedecBN(&bn, "1"), 1)
+            || !TEST_BN_eq_word(bn, 1)
+            || !TEST_BN_ne_zero(bn)
+            || !TEST_BN_gt_zero(bn)
+            || !TEST_BN_ge_zero(bn)
+            || !TEST_BN_eq_one(bn)
+            || !TEST_BN_odd(bn))
+        goto err;
+    BN_free(bn);
+    bn = NULL;
+
+    if (!TEST_int_eq(parsedecBN(&bn, "-0"), 2)
+            || !TEST_BN_eq_zero(bn)
+            || !TEST_BN_ge_zero(bn)
+            || !TEST_BN_le_zero(bn)
+            || !TEST_BN_even(bn))
+        goto err;
+    BN_free(bn);
+    bn = NULL;
+
+    if (!TEST_int_eq(parsedecBN(&bn, "42trailing garbage is ignored"), 2)
+            || !TEST_BN_abs_eq_word(bn, 42)
+            || !TEST_BN_ge_zero(bn)
+            || !TEST_BN_gt_zero(bn)
+            || !TEST_BN_ne_zero(bn)
+            || !TEST_BN_even(bn))
+        goto err;
+
+    st = 1;
+ err:
+    BN_free(bn);
+    return st;
+}
+
+static int test_hex2bn(void)
+{
+    BIGNUM *bn = NULL;
+    int st = 0;
+
+    if (!TEST_int_eq(parseBN(&bn, "0"), 1)
+            || !TEST_BN_eq_zero(bn)
+            || !TEST_BN_ge_zero(bn)
+            || !TEST_BN_even(bn))
+        goto err;
+    BN_free(bn);
+    bn = NULL;
+
+    if (!TEST_int_eq(parseBN(&bn, "256"), 3)
+            || !TEST_BN_eq_word(bn, 0x256)
+            || !TEST_BN_ge_zero(bn)
+            || !TEST_BN_gt_zero(bn)
+            || !TEST_BN_ne_zero(bn)
+            || !TEST_BN_even(bn))
+        goto err;
+    BN_free(bn);
+    bn = NULL;
+
+    if (!TEST_int_eq(parseBN(&bn, "-42"), 3)
+            || !TEST_BN_abs_eq_word(bn, 0x42)
+            || !TEST_BN_lt_zero(bn)
+            || !TEST_BN_le_zero(bn)
+            || !TEST_BN_ne_zero(bn)
+            || !TEST_BN_even(bn))
+        goto err;
+    BN_free(bn);
+    bn = NULL;
+
+    if (!TEST_int_eq(parseBN(&bn, "cb"), 2)
+            || !TEST_BN_eq_word(bn, 0xCB)
+            || !TEST_BN_ge_zero(bn)
+            || !TEST_BN_gt_zero(bn)
+            || !TEST_BN_ne_zero(bn)
+            || !TEST_BN_odd(bn))
+        goto err;
+    BN_free(bn);
+    bn = NULL;
+
+    if (!TEST_int_eq(parseBN(&bn, "-0"), 2)
+            || !TEST_BN_eq_zero(bn)
+            || !TEST_BN_ge_zero(bn)
+            || !TEST_BN_le_zero(bn)
+            || !TEST_BN_even(bn))
+        goto err;
+    BN_free(bn);
+    bn = NULL;
+
+    if (!TEST_int_eq(parseBN(&bn, "abctrailing garbage is ignored"), 3)
+            || !TEST_BN_eq_word(bn, 0xabc)
+            || !TEST_BN_ge_zero(bn)
+            || !TEST_BN_gt_zero(bn)
+            || !TEST_BN_ne_zero(bn)
+            || !TEST_BN_even(bn))
+        goto err;
+    st = 1;
+
+ err:
+    BN_free(bn);
+    return st;
+}
+
+static int test_asc2bn(void)
+{
+    BIGNUM *bn = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(bn = BN_new()))
+        goto err;
+
+    if (!TEST_true(BN_asc2bn(&bn, "0"))
+            || !TEST_BN_eq_zero(bn)
+            || !TEST_BN_ge_zero(bn))
+        goto err;
+
+    if (!TEST_true(BN_asc2bn(&bn, "256"))
+            || !TEST_BN_eq_word(bn, 256)
+            || !TEST_BN_ge_zero(bn))
+        goto err;
+
+    if (!TEST_true(BN_asc2bn(&bn, "-42"))
+            || !TEST_BN_abs_eq_word(bn, 42)
+            || !TEST_BN_lt_zero(bn))
+        goto err;
+
+    if (!TEST_true(BN_asc2bn(&bn, "0x1234"))
+            || !TEST_BN_eq_word(bn, 0x1234)
+            || !TEST_BN_ge_zero(bn))
+        goto err;
+
+    if (!TEST_true(BN_asc2bn(&bn, "0X1234"))
+            || !TEST_BN_eq_word(bn, 0x1234)
+            || !TEST_BN_ge_zero(bn))
+        goto err;
+
+    if (!TEST_true(BN_asc2bn(&bn, "-0xabcd"))
+            || !TEST_BN_abs_eq_word(bn, 0xabcd)
+            || !TEST_BN_lt_zero(bn))
+        goto err;
+
+    if (!TEST_true(BN_asc2bn(&bn, "-0"))
+            || !TEST_BN_eq_zero(bn)
+            || !TEST_BN_ge_zero(bn))
+        goto err;
+
+    if (!TEST_true(BN_asc2bn(&bn, "123trailing garbage is ignored"))
+            || !TEST_BN_eq_word(bn, 123)
+            || !TEST_BN_ge_zero(bn))
+        goto err;
+
+    st = 1;
+ err:
+    BN_free(bn);
+    return st;
+}
+
+static const MPITEST kMPITests[] = {
+    {"0", "\x00\x00\x00\x00", 4},
+    {"1", "\x00\x00\x00\x01\x01", 5},
+    {"-1", "\x00\x00\x00\x01\x81", 5},
+    {"128", "\x00\x00\x00\x02\x00\x80", 6},
+    {"256", "\x00\x00\x00\x02\x01\x00", 6},
+    {"-256", "\x00\x00\x00\x02\x81\x00", 6},
+};
+
+static int test_mpi(int i)
+{
+    uint8_t scratch[8];
+    const MPITEST *test = &kMPITests[i];
+    size_t mpi_len, mpi_len2;
+    BIGNUM *bn = NULL;
+    BIGNUM *bn2 = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(bn = BN_new())
+            || !TEST_true(BN_asc2bn(&bn, test->base10)))
+        goto err;
+    mpi_len = BN_bn2mpi(bn, NULL);
+    if (!TEST_size_t_le(mpi_len, sizeof(scratch)))
+        goto err;
+
+    if (!TEST_size_t_eq(mpi_len2 = BN_bn2mpi(bn, scratch), mpi_len)
+            || !TEST_mem_eq(test->mpi, test->mpi_len, scratch, mpi_len))
+        goto err;
+
+    if (!TEST_ptr(bn2 = BN_mpi2bn(scratch, mpi_len, NULL)))
+        goto err;
+
+    if (!TEST_BN_eq(bn, bn2)) {
+        BN_free(bn2);
+        goto err;
+    }
+    BN_free(bn2);
+
+    st = 1;
+ err:
+    BN_free(bn);
+    return st;
+}
+
+static int test_rand(void)
+{
+    BIGNUM *bn = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(bn = BN_new()))
+        return 0;
+
+    /* Test BN_rand for degenerate cases with |top| and |bottom| parameters. */
+    if (!TEST_false(BN_rand(bn, 0, 0 /* top */ , 0 /* bottom */ ))
+            || !TEST_false(BN_rand(bn, 0, 1 /* top */ , 1 /* bottom */ ))
+            || !TEST_true(BN_rand(bn, 1, 0 /* top */ , 0 /* bottom */ ))
+            || !TEST_BN_eq_one(bn)
+            || !TEST_false(BN_rand(bn, 1, 1 /* top */ , 0 /* bottom */ ))
+            || !TEST_true(BN_rand(bn, 1, -1 /* top */ , 1 /* bottom */ ))
+            || !TEST_BN_eq_one(bn)
+            || !TEST_true(BN_rand(bn, 2, 1 /* top */ , 0 /* bottom */ ))
+            || !TEST_BN_eq_word(bn, 3))
+        goto err;
+
+    st = 1;
+ err:
+    BN_free(bn);
+    return st;
+}
+
+static int test_negzero(void)
+{
+    BIGNUM *a = NULL, *b = NULL, *c = NULL, *d = NULL;
+    BIGNUM *numerator = NULL, *denominator = NULL;
+    int consttime, st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b = BN_new())
+            || !TEST_ptr(c = BN_new())
+            || !TEST_ptr(d = BN_new()))
+        goto err;
+
+    /* Test that BN_mul never gives negative zero. */
+    if (!TEST_true(BN_set_word(a, 1)))
+        goto err;
+    BN_set_negative(a, 1);
+    BN_zero(b);
+    if (!TEST_true(BN_mul(c, a, b, ctx)))
+        goto err;
+    if (!TEST_BN_eq_zero(c)
+            || !TEST_BN_ge_zero(c))
+        goto err;
+
+    for (consttime = 0; consttime < 2; consttime++) {
+        if (!TEST_ptr(numerator = BN_new())
+                || !TEST_ptr(denominator = BN_new()))
+            goto err;
+        if (consttime) {
+            BN_set_flags(numerator, BN_FLG_CONSTTIME);
+            BN_set_flags(denominator, BN_FLG_CONSTTIME);
+        }
+        /* Test that BN_div never gives negative zero in the quotient. */
+        if (!TEST_true(BN_set_word(numerator, 1))
+                || !TEST_true(BN_set_word(denominator, 2)))
+            goto err;
+        BN_set_negative(numerator, 1);
+        if (!TEST_true(BN_div(a, b, numerator, denominator, ctx))
+                || !TEST_BN_eq_zero(a)
+                || !TEST_BN_ge_zero(a))
+            goto err;
+
+        /* Test that BN_div never gives negative zero in the remainder. */
+        if (!TEST_true(BN_set_word(denominator, 1))
+                || !TEST_true(BN_div(a, b, numerator, denominator, ctx))
+                || !TEST_BN_eq_zero(b)
+                || !TEST_BN_ge_zero(b))
+            goto err;
+        BN_free(numerator);
+        BN_free(denominator);
+        numerator = denominator = NULL;
+    }
+
+    /* Test that BN_set_negative will not produce a negative zero. */
+    BN_zero(a);
+    BN_set_negative(a, 1);
+    if (BN_is_negative(a))
+        goto err;
+    st = 1;
+
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(c);
+    BN_free(d);
+    BN_free(numerator);
+    BN_free(denominator);
+    return st;
+}
+
+static int test_badmod(void)
+{
+    BIGNUM *a = NULL, *b = NULL, *zero = NULL;
+    BN_MONT_CTX *mont = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b = BN_new())
+            || !TEST_ptr(zero = BN_new())
+            || !TEST_ptr(mont = BN_MONT_CTX_new()))
+        goto err;
+    BN_zero(zero);
+
+    if (!TEST_false(BN_div(a, b, BN_value_one(), zero, ctx)))
+        goto err;
+    ERR_clear_error();
+
+    if (!TEST_false(BN_mod_mul(a, BN_value_one(), BN_value_one(), zero, ctx)))
+        goto err;
+    ERR_clear_error();
+
+    if (!TEST_false(BN_mod_exp(a, BN_value_one(), BN_value_one(), zero, ctx)))
+        goto err;
+    ERR_clear_error();
+
+    if (!TEST_false(BN_mod_exp_mont(a, BN_value_one(), BN_value_one(),
+                                    zero, ctx, NULL)))
+        goto err;
+    ERR_clear_error();
+
+    if (!TEST_false(BN_mod_exp_mont_consttime(a, BN_value_one(), BN_value_one(),
+                                              zero, ctx, NULL)))
+        goto err;
+    ERR_clear_error();
+
+    if (!TEST_false(BN_MONT_CTX_set(mont, zero, ctx)))
+        goto err;
+    ERR_clear_error();
+
+    /* Some operations also may not be used with an even modulus. */
+    if (!TEST_true(BN_set_word(b, 16)))
+        goto err;
+
+    if (!TEST_false(BN_MONT_CTX_set(mont, b, ctx)))
+        goto err;
+    ERR_clear_error();
+
+    if (!TEST_false(BN_mod_exp_mont(a, BN_value_one(), BN_value_one(),
+                                    b, ctx, NULL)))
+        goto err;
+    ERR_clear_error();
+
+    if (!TEST_false(BN_mod_exp_mont_consttime(a, BN_value_one(), BN_value_one(),
+                                              b, ctx, NULL)))
+        goto err;
+    ERR_clear_error();
+
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(zero);
+    BN_MONT_CTX_free(mont);
+    return st;
+}
+
+static int test_expmodzero(void)
+{
+    BIGNUM *a = NULL, *r = NULL, *zero = NULL;
+    int st = 0;
+
+    if (!TEST_ptr(zero = BN_new())
+            || !TEST_ptr(a = BN_new())
+            || !TEST_ptr(r = BN_new()))
+        goto err;
+    BN_zero(zero);
+
+    if (!TEST_true(BN_mod_exp(r, a, zero, BN_value_one(), NULL))
+            || !TEST_BN_eq_zero(r)
+            || !TEST_true(BN_mod_exp_mont(r, a, zero, BN_value_one(),
+                                          NULL, NULL))
+            || !TEST_BN_eq_zero(r)
+            || !TEST_true(BN_mod_exp_mont_consttime(r, a, zero,
+                                                    BN_value_one(),
+                                                    NULL, NULL))
+            || !TEST_BN_eq_zero(r)
+            || !TEST_true(BN_mod_exp_mont_word(r, 42, zero,
+                                               BN_value_one(), NULL, NULL))
+            || !TEST_BN_eq_zero(r))
+        goto err;
+
+    st = 1;
+ err:
+    BN_free(zero);
+    BN_free(a);
+    BN_free(r);
+    return st;
+}
+
+static int test_expmodone(void)
+{
+    int ret = 0, i;
+    BIGNUM *r = BN_new();
+    BIGNUM *a = BN_new();
+    BIGNUM *p = BN_new();
+    BIGNUM *m = BN_new();
+
+    if (!TEST_ptr(r)
+            || !TEST_ptr(a)
+            || !TEST_ptr(p)
+            || !TEST_ptr(p)
+            || !TEST_ptr(m)
+            || !TEST_true(BN_set_word(a, 1))
+            || !TEST_true(BN_set_word(p, 0))
+            || !TEST_true(BN_set_word(m, 1)))
+        goto err;
+
+    /* Calculate r = 1 ^ 0 mod 1, and check the result is always 0 */
+    for (i = 0; i < 2; i++) {
+        if (!TEST_true(BN_mod_exp(r, a, p, m, NULL))
+                || !TEST_BN_eq_zero(r)
+                || !TEST_true(BN_mod_exp_mont(r, a, p, m, NULL, NULL))
+                || !TEST_BN_eq_zero(r)
+                || !TEST_true(BN_mod_exp_mont_consttime(r, a, p, m, NULL, NULL))
+                || !TEST_BN_eq_zero(r)
+                || !TEST_true(BN_mod_exp_mont_word(r, 1, p, m, NULL, NULL))
+                || !TEST_BN_eq_zero(r)
+                || !TEST_true(BN_mod_exp_simple(r, a, p, m, NULL))
+                || !TEST_BN_eq_zero(r)
+                || !TEST_true(BN_mod_exp_recp(r, a, p, m, NULL))
+                || !TEST_BN_eq_zero(r))
+            goto err;
+        /* Repeat for r = 1 ^ 0 mod -1 */
+        if (i == 0)
+            BN_set_negative(m, 1);
+    }
+
+    ret = 1;
+ err:
+    BN_free(r);
+    BN_free(a);
+    BN_free(p);
+    BN_free(m);
+    return ret;
+}
+
+static int test_smallprime(int kBits)
+{
+    BIGNUM *r;
+    int st = 0;
+
+    if (!TEST_ptr(r = BN_new()))
+        goto err;
+
+    if (kBits <= 1) {
+        if (!TEST_false(BN_generate_prime_ex(r, kBits, 0,
+                                             NULL, NULL, NULL)))
+            goto err;
+    } else {
+        if (!TEST_true(BN_generate_prime_ex(r, kBits, 0,
+                                            NULL, NULL, NULL))
+                || !TEST_int_eq(BN_num_bits(r), kBits))
+            goto err;
+    }
+
+    st = 1;
+ err:
+    BN_free(r);
+    return st;
+}
+
+static int test_smallsafeprime(int kBits)
+{
+    BIGNUM *r;
+    int st = 0;
+
+    if (!TEST_ptr(r = BN_new()))
+        goto err;
+
+    if (kBits <= 5 && kBits != 3) {
+        if (!TEST_false(BN_generate_prime_ex(r, kBits, 1,
+                                             NULL, NULL, NULL)))
+            goto err;
+    } else {
+        if (!TEST_true(BN_generate_prime_ex(r, kBits, 1,
+                                            NULL, NULL, NULL))
+                || !TEST_int_eq(BN_num_bits(r), kBits))
+            goto err;
+    }
+
+    st = 1;
+ err:
+    BN_free(r);
+    return st;
+}
+
+static int primes[] = { 2, 3, 5, 7, 17863 };
+
+static int test_is_prime(int i)
+{
+    int ret = 0;
+    BIGNUM *r = NULL;
+    int trial;
+
+    if (!TEST_ptr(r = BN_new()))
+        goto err;
+
+    for (trial = 0; trial <= 1; ++trial) {
+        if (!TEST_true(BN_set_word(r, primes[i]))
+                || !TEST_int_eq(BN_is_prime_fasttest_ex(r, 1, ctx, trial, NULL),
+                                1))
+            goto err;
+    }
+
+    ret = 1;
+ err:
+    BN_free(r);
+    return ret;
+}
+
+static int not_primes[] = { -1, 0, 1, 4 };
+
+static int test_not_prime(int i)
+{
+    int ret = 0;
+    BIGNUM *r = NULL;
+    int trial;
+
+    if (!TEST_ptr(r = BN_new()))
+        goto err;
+
+    for (trial = 0; trial <= 1; ++trial) {
+        if (!TEST_true(BN_set_word(r, not_primes[i]))
+                || !TEST_false(BN_is_prime_fasttest_ex(r, 1, ctx, trial, NULL)))
+            goto err;
+    }
+
+    ret = 1;
+ err:
+    BN_free(r);
+    return ret;
+}
+
+static int test_ctx_set_ct_flag(BN_CTX *c)
+{
+    int st = 0;
+    size_t i;
+    BIGNUM *b[15];
+
+    BN_CTX_start(c);
+    for (i = 0; i < OSSL_NELEM(b); i++) {
+        if (!TEST_ptr(b[i] = BN_CTX_get(c)))
+            goto err;
+        if (i % 2 == 1)
+            BN_set_flags(b[i], BN_FLG_CONSTTIME);
+    }
+
+    st = 1;
+ err:
+    BN_CTX_end(c);
+    return st;
+}
+
+static int test_ctx_check_ct_flag(BN_CTX *c)
+{
+    int st = 0;
+    size_t i;
+    BIGNUM *b[30];
+
+    BN_CTX_start(c);
+    for (i = 0; i < OSSL_NELEM(b); i++) {
+        if (!TEST_ptr(b[i] = BN_CTX_get(c)))
+            goto err;
+        if (!TEST_false(BN_get_flags(b[i], BN_FLG_CONSTTIME)))
+            goto err;
+    }
+
+    st = 1;
+ err:
+    BN_CTX_end(c);
+    return st;
+}
+
+static int test_ctx_consttime_flag(void)
+{
+    /*-
+     * The constant-time flag should not "leak" among BN_CTX frames:
+     *
+     * - test_ctx_set_ct_flag() starts a frame in the given BN_CTX and
+     *   sets the BN_FLG_CONSTTIME flag on some of the BIGNUMs obtained
+     *   from the frame before ending it.
+     * - test_ctx_check_ct_flag() then starts a new frame and gets a
+     *   number of BIGNUMs from it. In absence of leaks, none of the
+     *   BIGNUMs in the new frame should have BN_FLG_CONSTTIME set.
+     *
+     * In actual BN_CTX usage inside libcrypto the leak could happen at
+     * any depth level in the BN_CTX stack, with varying results
+     * depending on the patterns of sibling trees of nested function
+     * calls sharing the same BN_CTX object, and the effect of
+     * unintended BN_FLG_CONSTTIME on the called BN_* functions.
+     *
+     * This simple unit test abstracts away this complexity and verifies
+     * that the leak does not happen between two sibling functions
+     * sharing the same BN_CTX object at the same level of nesting.
+     *
+     */
+    BN_CTX *nctx = NULL;
+    BN_CTX *sctx = NULL;
+    size_t i = 0;
+    int st = 0;
+
+    if (!TEST_ptr(nctx = BN_CTX_new())
+            || !TEST_ptr(sctx = BN_CTX_secure_new()))
+        goto err;
+
+    for (i = 0; i < 2; i++) {
+        BN_CTX *c = i == 0 ? nctx : sctx;
+        if (!TEST_true(test_ctx_set_ct_flag(c))
+                || !TEST_true(test_ctx_check_ct_flag(c)))
+            goto err;
+    }
+
+    st = 1;
+ err:
+    BN_CTX_free(nctx);
+    BN_CTX_free(sctx);
+    return st;
+}
+
+static int test_gcd_prime(void)
+{
+    BIGNUM *a = NULL, *b = NULL, *gcd = NULL;
+    int i, st = 0;
+
+    if (!TEST_ptr(a = BN_new())
+            || !TEST_ptr(b = BN_new())
+            || !TEST_ptr(gcd = BN_new()))
+        goto err;
+
+    if (!TEST_true(BN_generate_prime_ex(a, 1024, 0, NULL, NULL, NULL)))
+            goto err;
+    for (i = 0; i < NUM0; i++) {
+        if (!TEST_true(BN_generate_prime_ex(b, 1024, 0,
+                                            NULL, NULL, NULL))
+                || !TEST_true(BN_gcd(gcd, a, b, ctx))
+                || !TEST_true(BN_is_one(gcd)))
+            goto err;
+    }
+
+    st = 1;
+ err:
+    BN_free(a);
+    BN_free(b);
+    BN_free(gcd);
+    return st;
+}
+
+typedef struct mod_exp_test_st
+{
+  const char *base;
+  const char *exp;
+  const char *mod;
+  const char *res;
+} MOD_EXP_TEST;
+
+static const MOD_EXP_TEST ModExpTests[] = {
+   /* original test vectors for rsaz_512_sqr bug, by OSS-Fuzz */
+   {
+       "1166180238001879113042182292626169621106255558914000595999312084"
+       "4627946820899490684928760491249738643524880720584249698100907201"
+       "002086675047927600340800371",
+       "8000000000000000000000000000000000000000000000000000000000000000"
+       "0000000000000000000000000000000000000000000000000000000000000000"
+       "00000000",
+       "1340780792684523720980737645613191762604395855615117867483316354"
+       "3294276330515137663421134775482798690129946803802212663956180562"
+       "088664022929883876655300863",
+       "8243904058268085430037326628480645845409758077568738532059032482"
+       "8294114415890603594730158120426756266457928475330450251339773498"
+       "26758407619521544102068438"
+   },
+   {
+       "4974270041410803822078866696159586946995877618987010219312844726"
+       "0284386121835740784990869050050504348861513337232530490826340663"
+       "197278031692737429054",
+       "4974270041410803822078866696159586946995877428188754995041148539"
+       "1663243362592271353668158565195557417149981094324650322556843202"
+       "946445882670777892608",
+       "1340780716511420227215592830971452482815377482627251725537099028"
+       "4429769497230131760206012644403029349547320953206103351725462999"
+       "947509743623340557059752191",
+       "5296244594780707015616522701706118082963369547253192207884519362"
+       "1767869984947542695665420219028522815539559194793619684334900442"
+       "49304558011362360473525933"
+   },
+   /* test vectors for rsaz_512_srq bug, with rcx/rbx=1 */
+   {   /* between first and second iteration */
+       "5148719036160389201525610950887605325980251964889646556085286545"
+       "3931548809178823413169359635978762036512397113080988070677858033"
+       "36463909753993540214027190",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042158",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042159",
+       "1"
+   },
+   {   /* between second and third iteration */
+       "8908340854353752577419678771330460827942371434853054158622636544"
+       "8151360109722890949471912566649465436296659601091730745087014189"
+       "2672764191218875181826063",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042158",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042159",
+       "1"
+   },
+   {   /* between third and fourth iteration */
+       "3427446396505596330634350984901719674479522569002785244080234738"
+       "4288743635435746136297299366444548736533053717416735379073185344"
+       "26985272974404612945608761",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042158",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042159",
+       "1"
+   },
+   {   /* between fourth and fifth iteration */
+       "3472743044917564564078857826111874560045331237315597383869652985"
+       "6919870028890895988478351133601517365908445058405433832718206902"
+       "4088133164805266956353542",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042158",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042159",
+       "1"
+   },
+   {   /* between fifth and sixth iteration */
+       "3608632990153469264412378349742339216742409743898601587274768025"
+       "0110772032985643555192767717344946174122842255204082586753499651"
+       "14483434992887431333675068",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042158",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042159",
+       "1"
+   },
+   {   /* between sixth and seventh iteration */
+       "8455374370234070242910508226941981520235709767260723212165264877"
+       "8689064388017521524568434328264431772644802567028663962962025746"
+       "9283458217850119569539086",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042158",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042159",
+       "1"
+   },
+   {   /* between seventh and eighth iteration */
+       "5155371529688532178421209781159131443543419764974688878527112131"
+       "7446518205609427412336183157918981038066636807317733319323257603"
+       "04416292040754017461076359",
+       "1005585594745694782468051874865438459560952436544429503329267108"
+       "2791323022555160232601405723625177570767523893639864538140315412"
+       "108959927459825236754563832",
+       "1005585594745694782468051874865438459560952436544429503329267108"
+       "2791323022555160232601405723625177570767523893639864538140315412"
+       "108959927459825236754563833",
+       "1"
+   },
+   /* test vectors for rsaz_512_srq bug, with rcx/rbx=2 */
+   {   /* between first and second iteration */
+       "3155666506033786929967309937640790361084670559125912405342594979"
+       "4345142818528956285490897841406338022378565972533508820577760065"
+       "58494345853302083699912572",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042158",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042159",
+       "1"
+   },
+   {   /* between second and third iteration */
+       "3789819583801342198190405714582958759005991915505282362397087750"
+       "4213544724644823098843135685133927198668818185338794377239590049"
+       "41019388529192775771488319",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042158",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042159",
+       "1"
+   },
+   {   /* between third and forth iteration */
+       "4695752552040706867080542538786056470322165281761525158189220280"
+       "4025547447667484759200742764246905647644662050122968912279199065"
+       "48065034299166336940507214",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042158",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042159",
+       "1"
+   },
+   {   /* between forth and fifth iteration */
+       "2159140240970485794188159431017382878636879856244045329971239574"
+       "8919691133560661162828034323196457386059819832804593989740268964"
+       "74502911811812651475927076",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042158",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042159",
+       "1"
+   },
+   {   /* between fifth and sixth iteration */
+       "5239312332984325668414624633307915097111691815000872662334695514"
+       "5436533521392362443557163429336808208137221322444780490437871903"
+       "99972784701334569424519255",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042158",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042159",
+       "1"
+   },
+   {   /* between sixth and seventh iteration */
+       "1977953647322612860406858017869125467496941904523063466791308891"
+       "1172796739058531929470539758361774569875505293428856181093904091"
+       "33788264851714311303725089",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042158",
+       "6703903964971298549787012499102923063739682910296196688861780721"
+       "8608820150367734884009371490834517138450159290932430254268769414"
+       "05973284973216824503042159",
+       "1"
+   },
+   {   /* between seventh and eighth iteration */
+       "6456987954117763835533395796948878140715006860263624787492985786"
+       "8514630216966738305923915688821526449499763719943997120302368211"
+       "04813318117996225041943964",
+       "1340780792994259709957402499820584612747936582059239337772356144"
+       "3721764030073546976801874298166903427690031858186486050853753882"
+       "811946551499689575296532556",
+       "1340780792994259709957402499820584612747936582059239337772356144"
+       "3721764030073546976801874298166903427690031858186486050853753882"
+       "811946551499689575296532557",
+       "1"
+   }
+};
+
+static int test_mod_exp(int i)
+{
+    const MOD_EXP_TEST *test = &ModExpTests[i];
+    int res = 0;
+    BIGNUM* result = NULL;
+    BIGNUM *base = NULL, *exponent = NULL, *modulo = NULL;
+    char *s = NULL;
+
+    if (!TEST_ptr(result = BN_new())
+            || !TEST_true(BN_dec2bn(&base, test->base))
+            || !TEST_true(BN_dec2bn(&exponent, test->exp))
+            || !TEST_true(BN_dec2bn(&modulo, test->mod)))
+        goto err;
+
+    if (!TEST_int_eq(BN_mod_exp(result, base, exponent, modulo, ctx), 1))
+        goto err;
+
+    if (!TEST_ptr(s = BN_bn2dec(result)))
+        goto err;
+
+    if (!TEST_mem_eq(s, strlen(s), test->res, strlen(test->res)))
+        goto err;
+
+    res = 1;
+
+ err:
+    OPENSSL_free(s);
+    BN_free(result);
+    BN_free(base);
+    BN_free(exponent);
+    BN_free(modulo);
+    return res;
+}
+
+static int test_mod_exp_consttime(int i)
+{
+    const MOD_EXP_TEST *test = &ModExpTests[i];
+    int res = 0;
+    BIGNUM* result = NULL;
+    BIGNUM *base = NULL, *exponent = NULL, *modulo = NULL;
+    char *s = NULL;
+
+    if (!TEST_ptr(result = BN_new())
+            || !TEST_true(BN_dec2bn(&base, test->base))
+            || !TEST_true(BN_dec2bn(&exponent, test->exp))
+            || !TEST_true(BN_dec2bn(&modulo, test->mod)))
+        goto err;
+
+    BN_set_flags(base, BN_FLG_CONSTTIME);
+    BN_set_flags(exponent, BN_FLG_CONSTTIME);
+    BN_set_flags(modulo, BN_FLG_CONSTTIME);
+
+    if (!TEST_int_eq(BN_mod_exp(result, base, exponent, modulo, ctx), 1))
+        goto err;
+
+    if (!TEST_ptr(s = BN_bn2dec(result)))
+        goto err;
+
+    if (!TEST_mem_eq(s, strlen(s), test->res, strlen(test->res)))
+        goto err;
+
+    res = 1;
+
+ err:
+    OPENSSL_free(s);
+    BN_free(result);
+    BN_free(base);
+    BN_free(exponent);
+    BN_free(modulo);
+    return res;
+}
+
+/*
+ * Regression test to ensure BN_mod_exp2_mont fails safely if argument m is
+ * zero.
+ */
+static int test_mod_exp2_mont(void)
+{
+    int res = 0;
+    BIGNUM *exp_result = NULL;
+    BIGNUM *exp_a1 = NULL, *exp_p1 = NULL, *exp_a2 = NULL, *exp_p2 = NULL,
+           *exp_m = NULL;
+
+    if (!TEST_ptr(exp_result = BN_new())
+            || !TEST_ptr(exp_a1 = BN_new())
+            || !TEST_ptr(exp_p1 = BN_new())
+            || !TEST_ptr(exp_a2 = BN_new())
+            || !TEST_ptr(exp_p2 = BN_new())
+            || !TEST_ptr(exp_m = BN_new()))
+        goto err;
+
+    if (!TEST_true(BN_one(exp_a1))
+            || !TEST_true(BN_one(exp_p1))
+            || !TEST_true(BN_one(exp_a2))
+            || !TEST_true(BN_one(exp_p2)))
+        goto err;
+
+    BN_zero(exp_m);
+
+    /* input of 0 is even, so must fail */
+    if (!TEST_int_eq(BN_mod_exp2_mont(exp_result, exp_a1, exp_p1, exp_a2,
+                exp_p2, exp_m, ctx, NULL), 0))
+        goto err;
+
+    res = 1;
+
+err:
+    BN_free(exp_result);
+    BN_free(exp_a1);
+    BN_free(exp_p1);
+    BN_free(exp_a2);
+    BN_free(exp_p2);
+    BN_free(exp_m);
+    return res;
+}
+
+static int file_test_run(STANZA *s)
+{
+    static const FILETEST filetests[] = {
+        {"Sum", file_sum},
+        {"LShift1", file_lshift1},
+        {"LShift", file_lshift},
+        {"RShift", file_rshift},
+        {"Square", file_square},
+        {"Product", file_product},
+        {"Quotient", file_quotient},
+        {"ModMul", file_modmul},
+        {"ModExp", file_modexp},
+        {"Exp", file_exp},
+        {"ModSqrt", file_modsqrt},
+        {"GCD", file_gcd},
+    };
+    int numtests = OSSL_NELEM(filetests);
+    const FILETEST *tp = filetests;
+
+    for ( ; --numtests >= 0; tp++) {
+        if (findattr(s, tp->name) != NULL) {
+            if (!tp->func(s)) {
+                TEST_info("%s:%d: Failed %s test",
+                          s->test_file, s->start, tp->name);
+                return 0;
+            }
+            return 1;
+        }
+    }
+    TEST_info("%s:%d: Unknown test", s->test_file, s->start);
+    return 0;
+}
+
+static int run_file_tests(int i)
+{
+    STANZA *s = NULL;
+    char *testfile = test_get_argument(i);
+    int c;
+
+    if (!TEST_ptr(s = OPENSSL_zalloc(sizeof(*s))))
+        return 0;
+    if (!test_start_file(s, testfile)) {
+        OPENSSL_free(s);
+        return 0;
+    }
+
+    /* Read test file. */
+    while (!BIO_eof(s->fp) && test_readstanza(s)) {
+        if (s->numpairs == 0)
+            continue;
+        if (!file_test_run(s))
+            s->errors++;
+        s->numtests++;
+        test_clearstanza(s);
+    }
+    test_end_file(s);
+    c = s->errors;
+    OPENSSL_free(s);
+
+    return c == 0;
+}
+
+
+int setup_tests(void)
+{
+    int n = test_get_argument_count();
+
+    if (!TEST_ptr(ctx = BN_CTX_new()))
+        return 0;
+
+    if (n == 0) {
+        ADD_TEST(test_sub);
+        ADD_TEST(test_div_recip);
+        ADD_ALL_TESTS(test_signed_mod_replace_ab, OSSL_NELEM(signed_mod_tests));
+        ADD_ALL_TESTS(test_signed_mod_replace_ba, OSSL_NELEM(signed_mod_tests));
+        ADD_TEST(test_mod);
+        ADD_TEST(test_modexp_mont5);
+        ADD_TEST(test_kronecker);
+        ADD_TEST(test_rand);
+        ADD_TEST(test_bn2padded);
+        ADD_TEST(test_dec2bn);
+        ADD_TEST(test_hex2bn);
+        ADD_TEST(test_asc2bn);
+        ADD_ALL_TESTS(test_mpi, (int)OSSL_NELEM(kMPITests));
+        ADD_TEST(test_negzero);
+        ADD_TEST(test_badmod);
+        ADD_TEST(test_expmodzero);
+        ADD_TEST(test_expmodone);
+        ADD_ALL_TESTS(test_smallprime, 16);
+        ADD_ALL_TESTS(test_smallsafeprime, 16);
+        ADD_TEST(test_swap);
+        ADD_TEST(test_ctx_consttime_flag);
+#ifndef OPENSSL_NO_EC2M
+        ADD_TEST(test_gf2m_add);
+        ADD_TEST(test_gf2m_mod);
+        ADD_TEST(test_gf2m_mul);
+        ADD_TEST(test_gf2m_sqr);
+        ADD_TEST(test_gf2m_modinv);
+        ADD_TEST(test_gf2m_moddiv);
+        ADD_TEST(test_gf2m_modexp);
+        ADD_TEST(test_gf2m_modsqrt);
+        ADD_TEST(test_gf2m_modsolvequad);
+#endif
+        ADD_ALL_TESTS(test_is_prime, (int)OSSL_NELEM(primes));
+        ADD_ALL_TESTS(test_not_prime, (int)OSSL_NELEM(not_primes));
+        ADD_TEST(test_gcd_prime);
+        ADD_ALL_TESTS(test_mod_exp, (int)OSSL_NELEM(ModExpTests));
+        ADD_ALL_TESTS(test_mod_exp_consttime, (int)OSSL_NELEM(ModExpTests));
+        ADD_TEST(test_mod_exp2_mont);
+    } else {
+        ADD_ALL_TESTS(run_file_tests, n);
+    }
+    return 1;
+}
+
+void cleanup_tests(void)
+{
+    BN_CTX_free(ctx);
+}