diff --git a/ap/lib/libssl/openssl-1.1.1o/fuzz/bignum.c b/ap/lib/libssl/openssl-1.1.1o/fuzz/bignum.c
new file mode 100644
index 0000000..c513660
--- /dev/null
+++ b/ap/lib/libssl/openssl-1.1.1o/fuzz/bignum.c
@@ -0,0 +1,109 @@
+/*
+ * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL licenses, (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * https://www.openssl.org/source/license.html
+ * or in the file LICENSE in the source distribution.
+ */
+
+/*
+ * Confirm that a^b mod c agrees when calculated cleverly vs naively, for
+ * random a, b and c.
+ */
+
+#include <stdio.h>
+#include <openssl/bn.h>
+#include <openssl/err.h>
+#include "fuzzer.h"
+
+
+int FuzzerInitialize(int *argc, char ***argv)
+{
+    OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CRYPTO_STRINGS, NULL);
+    ERR_get_state();
+
+    return 1;
+}
+
+int FuzzerTestOneInput(const uint8_t *buf, size_t len)
+{
+    int success = 0;
+    size_t l1 = 0, l2 = 0, l3 = 0;
+    int s1 = 0, s3 = 0;
+    BN_CTX *ctx;
+    BIGNUM *b1;
+    BIGNUM *b2;
+    BIGNUM *b3;
+    BIGNUM *b4;
+    BIGNUM *b5;
+
+    b1 = BN_new();
+    b2 = BN_new();
+    b3 = BN_new();
+    b4 = BN_new();
+    b5 = BN_new();
+    ctx = BN_CTX_new();
+
+    /* Divide the input into three parts, using the values of the first two
+     * bytes to choose lengths, which generate b1, b2 and b3. Use three bits
+     * of the third byte to choose signs for the three numbers.
+     */
+    if (len > 2) {
+        len -= 3;
+        l1 = (buf[0] * len) / 255;
+        ++buf;
+        l2 = (buf[0] * (len - l1)) / 255;
+        ++buf;
+        l3 = len - l1 - l2;
+
+        s1 = buf[0] & 1;
+        s3 = buf[0] & 4;
+        ++buf;
+    }
+    OPENSSL_assert(BN_bin2bn(buf, l1, b1) == b1);
+    BN_set_negative(b1, s1);
+    OPENSSL_assert(BN_bin2bn(buf + l1, l2, b2) == b2);
+    OPENSSL_assert(BN_bin2bn(buf + l1 + l2, l3, b3) == b3);
+    BN_set_negative(b3, s3);
+
+    /* mod 0 is undefined */
+    if (BN_is_zero(b3)) {
+        success = 1;
+        goto done;
+    }
+
+    OPENSSL_assert(BN_mod_exp(b4, b1, b2, b3, ctx));
+    OPENSSL_assert(BN_mod_exp_simple(b5, b1, b2, b3, ctx));
+
+    success = BN_cmp(b4, b5) == 0;
+    if (!success) {
+        BN_print_fp(stdout, b1);
+        putchar('\n');
+        BN_print_fp(stdout, b2);
+        putchar('\n');
+        BN_print_fp(stdout, b3);
+        putchar('\n');
+        BN_print_fp(stdout, b4);
+        putchar('\n');
+        BN_print_fp(stdout, b5);
+        putchar('\n');
+    }
+
+ done:
+    OPENSSL_assert(success);
+    BN_free(b1);
+    BN_free(b2);
+    BN_free(b3);
+    BN_free(b4);
+    BN_free(b5);
+    BN_CTX_free(ctx);
+    ERR_clear_error();
+
+    return 0;
+}
+
+void FuzzerCleanup(void)
+{
+}