OSSL_CMP_MSG_GET0_HEADER(3ossl)

okay so bestie, welcome to the OSSL_CMP_MSG_GET0_HEADER(3ossl) page from the OpenSSL manual — this is literally the page for function(s) manipulating CMP messages, and we're gonna get you comfy with every single one 💅✨

🌸 NAME 🌸

This page is the main character energy for these function(s) manipulating CMP messages:

• OSSL_CMP_MSG_get0_header
• OSSL_CMP_MSG_get_bodytype
• OSSL_CMP_MSG_get0_certreq_publickey
• OSSL_CMP_MSG_update_transactionID
• OSSL_CMP_MSG_update_recipNonce
• OSSL_CMP_CTX_setup_CRM
• OSSL_CMP_MSG_read
• OSSL_CMP_MSG_write
• d2i_OSSL_CMP_MSG_bio
• i2d_OSSL_CMP_MSG_bio

✨ SYNOPSIS ✨

ok so the include and signatures go a little like this, no cap:

         #include <openssl/cmp.h>

         OSSL_CMP_PKIHEADER *OSSL_CMP_MSG_get0_header(const OSSL_CMP_MSG *msg);
         int OSSL_CMP_MSG_get_bodytype(const OSSL_CMP_MSG *msg);
         X509_PUBKEY *OSSL_CMP_MSG_get0_certreq_publickey(const OSSL_CMP_MSG *msg);
         int OSSL_CMP_MSG_update_transactionID(OSSL_CMP_CTX *ctx, OSSL_CMP_MSG *msg);
         int OSSL_CMP_MSG_update_recipNonce(OSSL_CMP_CTX *ctx, OSSL_CMP_MSG *msg);
         OSSL_CRMF_MSG *OSSL_CMP_CTX_setup_CRM(OSSL_CMP_CTX *ctx, int for_KUR, int rid);
         OSSL_CMP_MSG *OSSL_CMP_MSG_read(const char *file, OSSL_LIB_CTX *libctx, const char *propq);
         int OSSL_CMP_MSG_write(const char *file, const OSSL_CMP_MSG *msg);
         OSSL_CMP_MSG *d2i_OSSL_CMP_MSG_bio(BIO *bio, OSSL_CMP_MSG **msg);
         int i2d_OSSL_CMP_MSG_bio(BIO *bio, const OSSL_CMP_MSG *msg);

💖 DESCRIPTION 💖

Here's the vibe check on each function, bestie:

• OSSL_CMP_MSG_get0_header() — returns the header of the given CMP message. 🎀
• OSSL_CMP_MSG_get_bodytype() — returns the body type of the given CMP message.
• OSSL_CMP_MSG_get0_certreq_publickey() — expects that msg is a certificate request message and returns the public key in its certificate template if present.
• OSSL_CMP_MSG_update_transactionID() — updates the transactionID field in the header of the given message according to the CMP_CTX. If ctx does not contain a transaction ID, a fresh one is created before. The message gets re-protected (if protecting requests is required).
• OSSL_CMP_MSG_update_recipNonce() — updates the recipNonce field in the header of the given message according to the CMP_CTX. The message gets re-protected (if protecting requests is required).
• OSSL_CMP_CTX_setup_CRM() — creates a CRMF certificate request message from various information provided in the CMP context argument ctx for inclusion in a CMP request message based on details contained in ctx. The rid argument defines the request identifier to use, which typically is 0.

The subject DN included in the certificate template is the first available value of these:

• any subject name in ctx set via OSSL_CMP_CTX_set1_subjectName(3) — if it is the NULL-DN (i.e., any empty sequence of RDNs), no subject is included,
• the subject field of any PKCS#10 CSR set in ctx via OSSL_CMP_CTX_set1_p10CSR(3),
• the subject field of any reference certificate given in ctx (see OSSL_CMP_CTX_set1_oldCert(3)), but only if for_KUR is nonzero or the ctx does not include a Subject Alternative Name.

The public key included is the first available value of these:

• the public key derived from any key set via OSSL_CMP_CTX_set0_newPkey(3),
• the public key of any PKCS#10 CSR given in ctx,
• the public key of any reference certificate given in ctx (see OSSL_CMP_CTX_set1_oldCert(3)),
• the public key derived from any client's private key set via OSSL_CMP_CTX_set1_pkey(3).

The set of X.509 extensions to include is computed as follows. If a PKCS#10 CSR is present in ctx, default extensions are taken from there, otherwise the empty set is taken as the initial value. If there is a reference certificate in ctx and contains Subject Alternative Names (SANs) and OSSL_CMP_OPT_SUBJECTALTNAME_NODEFAULT is not set, these override any SANs from the PKCS#10 CSR. The extensions are further augmented or overridden by any extensions with the same OIDs included in the ctx via OSSL_CMP_CTX_set0_reqExtensions(3). The SANs are further overridden by any SANs included in ctx via OSSL_CMP_CTX_push1_subjectAltName(3). Finally, policies are overridden by any policies included in ctx via OSSL_CMP_CTX_push0_policy(3).

OSSL_CMP_CTX_setup_CRM() also sets the regToken control oldCertID for KUR messages using the issuer name and serial number of the reference certificate, if present.

OSSL_CMP_MSG_read() loads a DER-encoded OSSL_CMP_MSG from file.

OSSL_CMP_MSG_write() stores the given OSSL_CMP_MSG to file in DER encoding.

d2i_OSSL_CMP_MSG_bio() parses an ASN.1-encoded OSSL_CMP_MSG from the BIO bio. It assigns a pointer to the new structure to *msg if msg is not NULL.

i2d_OSSL_CMP_MSG_bio() writes the OSSL_CMP_MSG msg in ASN.1 encoding to BIO bio.

🦋 NOTES 🦋

CMP is defined in RFC 9810.

🎀 RETURN VALUES 🎀

Here's what you get back, bestie:

• OSSL_CMP_MSG_get0_header() — returns the intended pointer value as described above or NULL if the respective entry does not exist and on error.
• OSSL_CMP_MSG_get_bodytype() — returns the body type or -1 on error.
• OSSL_CMP_MSG_get0_certreq_publickey() — returns a public key or NULL on error.
• OSSL_CMP_CTX_setup_CRM() — returns a pointer to a OSSL_CRMF_MSG on success, NULL on error.
• d2i_OSSL_CMP_MSG_bio() — returns the parsed message or NULL on error.
• OSSL_CMP_MSG_read() and d2i_OSSL_CMP_MSG_bio() — return the parsed CMP message or NULL on error.
• OSSL_CMP_MSG_write() — returns the number of bytes successfully encoded or a negative value if an error occurs.
• i2d_OSSL_CMP_MSG_bio(), OSSL_CMP_MSG_update_transactionID(), and OSSL_CMP_MSG_update_recipNonce() — return 1 on success, 0 on error.

🌈 SEE ALSO 🌈

• OSSL_CMP_CTX_set1_subjectName(3)
• OSSL_CMP_CTX_set1_p10CSR(3)
• OSSL_CMP_CTX_set1_oldCert(3)
• OSSL_CMP_CTX_set0_newPkey(3)
• OSSL_CMP_CTX_set1_pkey(3)
• OSSL_CMP_CTX_set0_reqExtensions(3)
• OSSL_CMP_CTX_push1_subjectAltName(3)
• OSSL_CMP_CTX_push0_policy(3)

⭐ HISTORY ⭐

• The OpenSSL CMP support was added in OpenSSL 3.0.
• OSSL_CMP_MSG_update_recipNonce() was added in OpenSSL 3.0.9.
• OSSL_CMP_MSG_get0_certreq_publickey() was added in OpenSSL 3.3.

👑 COPYRIGHT 👑

Copyright 2007-2024 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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okay bestie, that's the whole page — signing off with the footer deets: source/version 3.5.6, dated 2026-04-07 💖🫶