X509_load_http, X509_http_nbio, X509_CRL_load_http, X509_CRL_http_nbio - certificate and CRL loading

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       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>.

3.5.0                                              2025-06-04                               X509_LOAD_HTTP(3SSL)

X509_load_http() and X509_CRL_load_http() loads a certificate or a CRL, respectively, in ASN.1 format
       using HTTP from the given url.

       Maximum size of the HTTP response is 100 kB for certificates and 32 MB for CRLs and hard coded in the
       functions.

       If bio is given and rbio is NULL then this BIO is used instead of an internal one for connecting, writing
       the request, and reading the response.  If both bio and rbio are given (which may be memory BIOs, for
       instance) then no explicit connection is attempted, bio is used for writing the request, and rbio for
       reading the response.

       If the timeout parameter is > 0 this indicates the maximum number of seconds to wait until the transfer
       is complete.  A value of 0 enables waiting indefinitely, while a value < 0 immediately leads to a timeout
       condition.

       X509_http_nbio() and X509_CRL_http_nbio() are macros for backward compatibility that have the same effect
       as the functions above but with infinite timeout and without the possibility to specify custom BIOs.

X509_load_http() and X509_CRL_load_http() were added in OpenSSL 3.0.  X509_http_nbio() and
       X509_CRL_http_nbio() were deprecated in OpenSSL 3.0.

       X509_load_http, X509_http_nbio, X509_CRL_load_http, X509_CRL_http_nbio - certificate and CRL loading
       functions

       On success the function yield the loaded value, else NULL.  Error conditions include connection/transfer
       timeout, parse errors, etc.

OSSL_HTTP_get(3)

        #include <openssl/x509.h>

        X509 *X509_load_http(const char *url, BIO *bio, BIO *rbio, int timeout);
        X509_CRL *X509_CRL_load_http(const char *url, BIO *bio, BIO *rbio, int timeout);

       The following macros have been deprecated since OpenSSL 3.0, and can be hidden entirely by defining
       OPENSSL_API_COMPAT with a suitable version value, see openssl_user_macros(7):

        #define X509_http_nbio(rctx, pcert)
        #define X509_CRL_http_nbio(rctx, pcrl)