Updated: 2022/Sep/29

Please read Privacy Policy. It's for your privacy.

OSSL_SELF_TEST_new(3)               OpenSSL              OSSL_SELF_TEST_new(3)



NAME
       OSSL_SELF_TEST_new, OSSL_SELF_TEST_free, OSSL_SELF_TEST_onbegin,
       OSSL_SELF_TEST_oncorrupt_byte, OSSL_SELF_TEST_onend - functionality to
       trigger a callback during a self test

LIBRARY
       libcrypto, -lcrypto

SYNOPSIS
        #include <openssl/self_test.h>

        OSSL_SELF_TEST *OSSL_SELF_TEST_new(OSSL_CALLBACK *cb, void *cbarg);
        void OSSL_SELF_TEST_free(OSSL_SELF_TEST *st);

        void OSSL_SELF_TEST_onbegin(OSSL_SELF_TEST *st, const char *type,
                                    const char *desc);
        int OSSL_SELF_TEST_oncorrupt_byte(OSSL_SELF_TEST *st, unsigned char *bytes);
        void OSSL_SELF_TEST_onend(OSSL_SELF_TEST *st, int ret);

DESCRIPTION
       These methods are intended for use by provider implementers, to display
       diagnostic information during self testing.

       OSSL_SELF_TEST_new() allocates an opaque OSSL_SELF_TEST object that has
       a callback and callback argument associated with it.

       The callback cb may be triggered multiple times by a self test to
       indicate different phases.

       OSSL_SELF_TEST_free() frees the space allocated by
       OSSL_SELF_TEST_new().

       OSSL_SELF_TEST_onbegin() may be inserted at the start of a block of
       self test code. It can be used for diagnostic purposes.  If this method
       is called the callback cb will receive the following OSSL_PARAM(3)
       object.

       "st-phase" (OSSL_PROV_PARAM_SELF_TEST_PHASE) <UTF8 string>
           The value is the string "Start"

       OSSL_SELF_TEST_oncorrupt_byte() may be inserted just after the known
       answer is calculated, but before the self test compares the result. The
       first byte in the passed in array of bytes will be corrupted if the
       callback returns 0, otherwise it leaves the array unaltered. It can be
       used for failure testing.  The type and desc can be used to identify an
       individual self test to target for failure testing.  If this method is
       called the callback cb will receive the following OSSL_PARAM(3) object.

       "st-phase" (OSSL_PROV_PARAM_SELF_TEST_PHASE) <UTF8 string>
           The value is the string "Corrupt"

       OSSL_SELF_TEST_onend() may be inserted at the end of a block of self
       test code just before cleanup to indicate if the test passed or failed.
       It can be used for diagnostic purposes.  If this method is called the
       callback cb will receive the following OSSL_PARAM(3) object.

       "st-phase" (OSSL_PROV_PARAM_SELF_TEST_PHASE) <UTF8 string>
           The value of the string is "Pass" if ret is non zero, otherwise it
           has the value "Fail".

       After the callback cb has been called the values that were set by
       OSSL_SELF_TEST_onbegin() for type and desc are set to the value "None".

       If OSSL_SELF_TEST_onbegin(), OSSL_SELF_TEST_oncorrupt_byte() or
       OSSL_SELF_TEST_onend() is called the following additional OSSL_PARAM(3)
       are passed to the callback.

       "st-type" (OSSL_PROV_PARAM_SELF_TEST_TYPE) <UTF8 string>
           The value is setup by the type passed to OSSL_SELF_TEST_onbegin().
           This allows the callback to identify the type of test being run.

       "st-desc" (OSSL_PROV_PARAM_SELF_TEST_DESC) <UTF8 string>
           The value is setup by the type passed to OSSL_SELF_TEST_onbegin().
           This allows the callback to identify the sub category of the test
           being run.

RETURN VALUES
       OSSL_SELF_TEST_new() returns the allocated OSSL_SELF_TEST object, or
       NULL if it fails.

       OSSL_SELF_TEST_oncorrupt_byte() returns 1 if corruption occurs,
       otherwise it returns 0.

EXAMPLES
       A single self test could be set up in the following way:

           OSSL_SELF_TEST *st = NULL;
           OSSL_CALLBACK *cb;
           void *cbarg;
           int ok = 0;
           unsigned char out[EVP_MAX_MD_SIZE];
           unsigned int out_len = 0;
           EVP_MD_CTX *ctx = EVP_MD_CTX_new();
           EVP_MD *md = EVP_MD_fetch(libctx, t->algorithm, NULL);

           /*
            * Retrieve the callback - will be NULL if not set by the application via
            * OSSL_SELF_TEST_set_callback().
            */
           OSSL_SELF_TEST_get_callback(libctx, &cb, &cbarg);

           st = OSSL_SELF_TEST_new(cb, cb_arg);

           /* Trigger the optional callback */
           OSSL_SELF_TEST_onbegin(st, OSSL_SELF_TEST_TYPE_KAT_DIGEST,
                                  OSSL_SELF_TEST_DESC_MD_SHA2);

           if (!EVP_DigestInit_ex(ctx, md, NULL)
               || !EVP_DigestUpdate(ctx, pt, pt_len)
               || !EVP_DigestFinal(ctx, out, &out_len))
               goto err;

           /* Optional corruption - If the application callback returns 0 */
           OSSL_SELF_TEST_oncorrupt_byte(st, out);

           if (out_len != t->expected_len
               || memcmp(out, t->expected, out_len) != 0)
               goto err;
           ok = 1;
         err:
           OSSL_SELF_TEST_onend(st, ok);
           EVP_MD_free(md);
           EVP_MD_CTX_free(ctx);

       Multiple self test's can be set up in a similar way by repeating the
       pattern of OSSL_SELF_TEST_onbegin(), OSSL_SELF_TEST_oncorrupt_byte(),
       OSSL_SELF_TEST_onend() for each test.

SEE ALSO
       OSSL_SELF_TEST_set_callback(3), openssl-core.h(7),
       OSSL_PROVIDER-FIPS(7)

HISTORY
       The functions described here were added in OpenSSL 3.0.

COPYRIGHT
       Copyright 2020-2023 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the Apache License 2.0 (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>.



3.0.12                            2023-10-25             OSSL_SELF_TEST_new(3)