X509_LOAD_HTTP(3ossl)

🌸 NAME 🌸

X509_load_http, X509_http_nbio, X509_CRL_load_http, X509_CRL_http_nbio — certificate and CRL loading functions. Welcome to the X509_LOAD_HTTP(3ossl) manual page, bestie 💖 this is the one about loading certs and CRLs.

✨ SYNOPSIS ✨

#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);

Ok so 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)

🦋 DESCRIPTION 🦋

X509_load_http() and X509_CRL_load_http() load a certificate or a CRL, respectively, in ASN.1 format using HTTP from the given url. That's the assignment, no cap ✨

Maximum size of the HTTP response is 100 kB for certificates and 32 MB for CRLs and hard coded in the functions. Yes bestie — hard coded, those are the ceilings 💅

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. Literally: positive waits up to that many seconds, zero waits indefinitely, negative says timeout immediately 💀

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.

🎀 RETURN VALUES 🎀

On success the function yield the loaded value, else NULL. Error conditions include connection/transfer timeout, parse errors, etc. So check for NULL, bestie — it's giving "something went wrong" energy 😭

🔥 SEE ALSO 🔥

• OSSL_HTTP_get(3) — the related manual page; go read it if you want the HTTP-get lore 👀

💜 HISTORY 💜

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. Periodt.

👑 COPYRIGHT 👑

Copyright 2019-2021 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>.

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Signing off from OpenSSL 3.5.6, dated 2026-04-07 🫶💖 stay iconic, bestie ✨