OSSL_CMP_CTX_new¶

NAME¶

OSSL_CMP_CTX_new, OSSL_CMP_CTX_free, OSSL_CMP_CTX_reinit, OSSL_CMP_CTX_get0_libctx, OSSL_CMP_CTX_get0_propq, OSSL_CMP_CTX_set_option, OSSL_CMP_CTX_get_option, OSSL_CMP_CTX_set_log_cb, OSSL_CMP_CTX_set_log_verbosity, OSSL_CMP_CTX_print_errors, OSSL_CMP_CTX_set1_serverPath, OSSL_CMP_CTX_set1_server, OSSL_CMP_CTX_set_serverPort, OSSL_CMP_CTX_set1_proxy, OSSL_CMP_CTX_set1_no_proxy, OSSL_CMP_CTX_set_http_cb, OSSL_CMP_CTX_set_http_cb_arg, OSSL_CMP_CTX_get_http_cb_arg, OSSL_CMP_transfer_cb_t, OSSL_CMP_CTX_set_transfer_cb, OSSL_CMP_CTX_set_transfer_cb_arg, OSSL_CMP_CTX_get_transfer_cb_arg, OSSL_CMP_CTX_set1_srvCert, OSSL_CMP_CTX_set1_expected_sender, OSSL_CMP_CTX_set0_trusted, OSSL_CMP_CTX_set0_trustedStore, OSSL_CMP_CTX_get0_trusted, OSSL_CMP_CTX_get0_trustedStore, OSSL_CMP_CTX_set1_untrusted, OSSL_CMP_CTX_get0_untrusted, OSSL_CMP_CTX_set1_cert, OSSL_CMP_CTX_build_cert_chain, OSSL_CMP_CTX_set1_pkey, OSSL_CMP_CTX_set1_referenceValue, OSSL_CMP_CTX_set1_secretValue, OSSL_CMP_CTX_set1_recipient, OSSL_CMP_CTX_push0_geninfo_ITAV, OSSL_CMP_CTX_reset_geninfo_ITAVs, OSSL_CMP_CTX_get0_geninfo_ITAVs, OSSL_CMP_CTX_set1_extraCertsOut, OSSL_CMP_CTX_set0_newPkey, OSSL_CMP_CTX_get0_newPkey, OSSL_CMP_CTX_set1_issuer, OSSL_CMP_CTX_set1_serialNumber, OSSL_CMP_CTX_set1_subjectName, OSSL_CMP_CTX_push1_subjectAltName, OSSL_CMP_CTX_set0_reqExtensions, OSSL_CMP_CTX_reqExtensions_have_SAN, OSSL_CMP_CTX_push0_policy, OSSL_CMP_CTX_set1_oldCert, OSSL_CMP_CTX_set1_p10CSR, OSSL_CMP_CTX_push0_genm_ITAV, OSSL_CMP_certConf_cb_t, OSSL_CMP_certConf_cb, OSSL_CMP_CTX_set_certConf_cb, OSSL_CMP_CTX_set_certConf_cb_arg, OSSL_CMP_CTX_get_certConf_cb_arg, OSSL_CMP_CTX_get_status, OSSL_CMP_CTX_get0_statusString, OSSL_CMP_CTX_get_failInfoCode, OSSL_CMP_CTX_get0_validatedSrvCert, OSSL_CMP_CTX_get0_newCert, OSSL_CMP_CTX_get1_newChain, OSSL_CMP_CTX_get1_caPubs, OSSL_CMP_CTX_get1_extraCertsIn, OSSL_CMP_CTX_set1_transactionID, OSSL_CMP_CTX_set1_senderNonce - functions for managing the CMP client context data structure

SYNOPSIS¶

#include <openssl/cmp.h>

OSSL_CMP_CTX *OSSL_CMP_CTX_new(OSSL_LIB_CTX *libctx, const char *propq);
void OSSL_CMP_CTX_free(OSSL_CMP_CTX *ctx);
int OSSL_CMP_CTX_reinit(OSSL_CMP_CTX *ctx);
OSSL_LIB_CTX *OSSL_CMP_CTX_get0_libctx(const OSSL_CMP_CTX *ctx);
const char *OSSL_CMP_CTX_get0_propq(const OSSL_CMP_CTX *ctx);
int OSSL_CMP_CTX_set_option(OSSL_CMP_CTX *ctx, int opt, int val);
int OSSL_CMP_CTX_get_option(const OSSL_CMP_CTX *ctx, int opt);

/* logging and error reporting: */
int OSSL_CMP_CTX_set_log_cb(OSSL_CMP_CTX *ctx, OSSL_CMP_log_cb_t cb);
#define OSSL_CMP_CTX_set_log_verbosity(ctx, level)
void OSSL_CMP_CTX_print_errors(const OSSL_CMP_CTX *ctx);

/* message transfer: */
int OSSL_CMP_CTX_set1_serverPath(OSSL_CMP_CTX *ctx, const char *path);
int OSSL_CMP_CTX_set1_server(OSSL_CMP_CTX *ctx, const char *address);
int OSSL_CMP_CTX_set_serverPort(OSSL_CMP_CTX *ctx, int port);
int OSSL_CMP_CTX_set1_proxy(OSSL_CMP_CTX *ctx, const char *name);
int OSSL_CMP_CTX_set1_no_proxy(OSSL_CMP_CTX *ctx, const char *names);
int OSSL_CMP_CTX_set_http_cb(OSSL_CMP_CTX *ctx, HTTP_bio_cb_t cb);
int OSSL_CMP_CTX_set_http_cb_arg(OSSL_CMP_CTX *ctx, void *arg);
void *OSSL_CMP_CTX_get_http_cb_arg(const OSSL_CMP_CTX *ctx);
typedef OSSL_CMP_MSG *(*OSSL_CMP_transfer_cb_t)(OSSL_CMP_CTX *ctx,
                                                const OSSL_CMP_MSG *req);
int OSSL_CMP_CTX_set_transfer_cb(OSSL_CMP_CTX *ctx,
                                 OSSL_CMP_transfer_cb_t cb);
int OSSL_CMP_CTX_set_transfer_cb_arg(OSSL_CMP_CTX *ctx, void *arg);
void *OSSL_CMP_CTX_get_transfer_cb_arg(const OSSL_CMP_CTX *ctx);

/* server authentication: */
int OSSL_CMP_CTX_set1_srvCert(OSSL_CMP_CTX *ctx, X509 *cert);
int OSSL_CMP_CTX_set1_expected_sender(OSSL_CMP_CTX *ctx,
                                     const X509_NAME *name);
#define OSSL_CMP_CTX_set0_trusted OSSL_CMP_CTX_set0_trustedStore
int OSSL_CMP_CTX_set0_trustedStore(OSSL_CMP_CTX *ctx, X509_STORE *store);
#define OSSL_CMP_CTX_get0_trusted OSSL_CMP_CTX_get0_trustedStore
X509_STORE *OSSL_CMP_CTX_get0_trustedStore(const OSSL_CMP_CTX *ctx);
int OSSL_CMP_CTX_set1_untrusted(OSSL_CMP_CTX *ctx, STACK_OF(X509) *certs);
STACK_OF(X509) *OSSL_CMP_CTX_get0_untrusted(const OSSL_CMP_CTX *ctx);

/* client authentication: */
int OSSL_CMP_CTX_set1_cert(OSSL_CMP_CTX *ctx, X509 *cert);
int OSSL_CMP_CTX_build_cert_chain(OSSL_CMP_CTX *ctx, X509_STORE *own_trusted,
                                  STACK_OF(X509) *candidates);
int OSSL_CMP_CTX_set1_pkey(OSSL_CMP_CTX *ctx, EVP_PKEY *pkey);
int OSSL_CMP_CTX_set1_referenceValue(OSSL_CMP_CTX *ctx,
                                     const unsigned char *ref, int len);
int OSSL_CMP_CTX_set1_secretValue(OSSL_CMP_CTX *ctx,
                                  const unsigned char *sec, int len);

/* CMP message header and extra certificates: */
int OSSL_CMP_CTX_set1_recipient(OSSL_CMP_CTX *ctx, const X509_NAME *name);
int OSSL_CMP_CTX_push0_geninfo_ITAV(OSSL_CMP_CTX *ctx, OSSL_CMP_ITAV *itav);
int OSSL_CMP_CTX_reset_geninfo_ITAVs(OSSL_CMP_CTX *ctx);
STACK_OF(OSSL_CMP_ITAV)
    *OSSL_CMP_CTX_get0_geninfo_ITAVs(const OSSL_CMP_CTX *ctx);
int OSSL_CMP_CTX_set1_extraCertsOut(OSSL_CMP_CTX *ctx,
                                    STACK_OF(X509) *extraCertsOut);

/* certificate template: */
int OSSL_CMP_CTX_set0_newPkey(OSSL_CMP_CTX *ctx, int priv, EVP_PKEY *pkey);
EVP_PKEY *OSSL_CMP_CTX_get0_newPkey(const OSSL_CMP_CTX *ctx, int priv);
int OSSL_CMP_CTX_set1_issuer(OSSL_CMP_CTX *ctx, const X509_NAME *name);
int OSSL_CMP_CTX_set1_serialNumber(OSSL_CMP_CTX *ctx, const ASN1_INTEGER *sn);
int OSSL_CMP_CTX_set1_subjectName(OSSL_CMP_CTX *ctx, const X509_NAME *name);
int OSSL_CMP_CTX_push1_subjectAltName(OSSL_CMP_CTX *ctx,
                                      const GENERAL_NAME *name);
int OSSL_CMP_CTX_set0_reqExtensions(OSSL_CMP_CTX *ctx, X509_EXTENSIONS *exts);
int OSSL_CMP_CTX_reqExtensions_have_SAN(OSSL_CMP_CTX *ctx);
int OSSL_CMP_CTX_push0_policy(OSSL_CMP_CTX *ctx, POLICYINFO *pinfo);
int OSSL_CMP_CTX_set1_oldCert(OSSL_CMP_CTX *ctx, X509 *cert);
int OSSL_CMP_CTX_set1_p10CSR(OSSL_CMP_CTX *ctx, const X509_REQ *csr);

/* misc body contents: */
int OSSL_CMP_CTX_push0_genm_ITAV(OSSL_CMP_CTX *ctx, OSSL_CMP_ITAV *itav);

/* certificate confirmation: */
typedef int (*OSSL_CMP_certConf_cb_t)(OSSL_CMP_CTX *ctx, X509 *cert,
                                      int fail_info, const char **txt);
int OSSL_CMP_certConf_cb(OSSL_CMP_CTX *ctx, X509 *cert, int fail_info,
                         const char **text);
int OSSL_CMP_CTX_set_certConf_cb(OSSL_CMP_CTX *ctx, OSSL_CMP_certConf_cb_t cb);
int OSSL_CMP_CTX_set_certConf_cb_arg(OSSL_CMP_CTX *ctx, void *arg);
void *OSSL_CMP_CTX_get_certConf_cb_arg(const OSSL_CMP_CTX *ctx);

/* result fetching: */
int OSSL_CMP_CTX_get_status(const OSSL_CMP_CTX *ctx);
OSSL_CMP_PKIFREETEXT *OSSL_CMP_CTX_get0_statusString(const OSSL_CMP_CTX *ctx);
int OSSL_CMP_CTX_get_failInfoCode(const OSSL_CMP_CTX *ctx);

X509 *OSSL_CMP_CTX_get0_validatedSrvCert(const OSSL_CMP_CTX *ctx);
X509 *OSSL_CMP_CTX_get0_newCert(const OSSL_CMP_CTX *ctx);
STACK_OF(X509) *OSSL_CMP_CTX_get1_newChain(const OSSL_CMP_CTX *ctx);
STACK_OF(X509) *OSSL_CMP_CTX_get1_caPubs(const OSSL_CMP_CTX *ctx);
STACK_OF(X509) *OSSL_CMP_CTX_get1_extraCertsIn(const OSSL_CMP_CTX *ctx);

/* for testing and debugging purposes: */
int OSSL_CMP_CTX_set1_transactionID(OSSL_CMP_CTX *ctx,
                                    const ASN1_OCTET_STRING *id);
int OSSL_CMP_CTX_set1_senderNonce(OSSL_CMP_CTX *ctx,
                                  const ASN1_OCTET_STRING *nonce);

DESCRIPTION¶

This is the context API for using CMP (Certificate Management Protocol) with OpenSSL.

OSSL_CMP_CTX_new() allocates an OSSL_CMP_CTX structure associated with the library context libctx and property query string propq, both of which may be NULL to select the defaults. It initializes the remaining fields to their default values - for instance, the logging verbosity is set to OSSL_CMP_LOG_INFO, the message timeout is set to 120 seconds, and the proof-of-possession method is set to OSSL_CRMF_POPO_SIGNATURE.

OSSL_CMP_CTX_free() deallocates an OSSL_CMP_CTX structure. If the argument is NULL, nothing is done.

OSSL_CMP_CTX_reinit() prepares the given ctx for a further transaction by clearing the internal CMP transaction (aka session) status, PKIStatusInfo, and any previous results (newCert, newChain, caPubs, and extraCertsIn) from the last executed transaction. It also clears any ITAVs that were added by OSSL_CMP_CTX_push0_genm_ITAV(). All other field values (i.e., CMP options) are retained for potential reuse.

OSSL_CMP_CTX_get0_libctx() returns the libctx argument that was used when constructing ctx with OSSL_CMP_CTX_new(), which may be NULL.

OSSL_CMP_CTX_get0_propq() returns the propq argument that was used when constructing ctx with OSSL_CMP_CTX_new(), which may be NULL.

OSSL_CMP_CTX_set_option() sets the given value for the given option (e.g., OSSL_CMP_OPT_IMPLICIT_CONFIRM) in the given OSSL_CMP_CTX structure.

The following options can be set:

OSSL_CMP_OPT_LOG_VERBOSITY

    The level of severity needed for actually outputting log messages
    due to errors, warnings, general info, debugging, etc.
    Default is OSSL_CMP_LOG_INFO. See also L<OSSL_CMP_log_open(3)>.

OSSL_CMP_OPT_KEEP_ALIVE

    If the given value is 0 then HTTP connections are not kept open
    after receiving a response, which is the default behavior for HTTP 1.0.
    If the value is 1 or 2 then persistent connections are requested.
    If the value is 2 then persistent connections are required,
    i.e., in case the server does not grant them an error occurs.
    The default value is 1: prefer to keep the connection open.

OSSL_CMP_OPT_MSG_TIMEOUT

    Number of seconds a CMP request-response message round trip
    is allowed to take before a timeout error is returned.
    A value <= 0 means no limitation (waiting indefinitely).
    Default is to use the B<OSSL_CMP_OPT_TOTAL_TIMEOUT> setting.

OSSL_CMP_OPT_TOTAL_TIMEOUT

    Maximum total number of seconds a transaction may take,
    including polling etc.
    A value <= 0 means no limitation (waiting indefinitely).
    Default is 0.

OSSL_CMP_OPT_USE_TLS

    Use this option to indicate to the HTTP implementation
    whether TLS is going to be used for the connection (resulting in HTTPS).
    The value 1 indicates that TLS is used for client-side HTTP connections,
    which needs to be implemented via a callback function set by
    OSSL_CMP_CTX_set_http_cb().
    The value 0 indicates that TLS is not used.
    Default is -1 for backward compatibility: TLS is used by the client side
    if and only if OSSL_CMP_CTX_set_http_cb_arg() sets a non-NULL I<arg>.

OSSL_CMP_OPT_VALIDITY_DAYS

    Number of days new certificates are asked to be valid for.

OSSL_CMP_OPT_SUBJECTALTNAME_NODEFAULT

    Do not take default Subject Alternative Names
    from the reference certificate.

OSSL_CMP_OPT_SUBJECTALTNAME_CRITICAL

    Demand that the given Subject Alternative Names are flagged as critical.

OSSL_CMP_OPT_POLICIES_CRITICAL

    Demand that the given policies are flagged as critical.

OSSL_CMP_OPT_POPO_METHOD

    Select the proof of possession method to use. Possible values are:

        OSSL_CRMF_POPO_NONE       - ProofOfPossession field omitted
        OSSL_CRMF_POPO_RAVERIFIED - assert that the RA has already
                                    verified the PoPo
        OSSL_CRMF_POPO_SIGNATURE  - sign a value with private key,
                                    which is the default.
        OSSL_CRMF_POPO_KEYENC     - decrypt the encrypted certificate
                                    ("indirect method")

    Note that a signature-based POPO can only be produced if a private key
    is provided as the newPkey or client's pkey component of the CMP context.

OSSL_CMP_OPT_DIGEST_ALGNID

    The NID of the digest algorithm to be used in RFC 4210's MSG_SIG_ALG
    for signature-based message protection and Proof-of-Possession (POPO).
    Default is SHA256.

OSSL_CMP_OPT_OWF_ALGNID The NID of the digest algorithm to be used as one-way function (OWF) for MAC-based message protection with password-based MAC (PBM). See RFC 4210 section 5.1.3.1 for details. Default is SHA256.
OSSL_CMP_OPT_MAC_ALGNID The NID of the MAC algorithm to be used for message protection with PBM. Default is HMAC-SHA1 as per RFC 4210.

OSSL_CMP_OPT_REVOCATION_REASON

    The reason code to be included in a Revocation Request (RR);
    values: 0..10 (RFC 5210, 5.3.1) or -1 for none, which is the default.

OSSL_CMP_OPT_IMPLICIT_CONFIRM

    Request server to enable implicit confirm mode, where the client
    does not need to send confirmation upon receiving the
    certificate. If the server does not enable implicit confirmation
    in the return message, then confirmation is sent anyway.

OSSL_CMP_OPT_DISABLE_CONFIRM
```
    Do not confirm enrolled certificates, to cope with broken servers
    not supporting implicit confirmation correctly.
```
B This setting leads to unspecified behavior and it is meant exclusively to allow interoperability with server implementations violating RFC 4210.

OSSL_CMP_OPT_UNPROTECTED_SEND

    Send request or response messages without CMP-level protection.

OSSL_CMP_OPT_UNPROTECTED_ERRORS

    Accept unprotected error responses which are either explicitly
    unprotected or where protection verification failed. Applies to regular
    error messages as well as certificate responses (IP/CP/KUP) and
    revocation responses (RP) with rejection.

B This setting leads to unspecified behavior and it is meant exclusively to allow interoperability with server implementations violating RFC 4210.

OSSL_CMP_OPT_IGNORE_KEYUSAGE

    Ignore key usage restrictions in the signer's certificate when
    validating signature-based protection in received CMP messages.
    Else, 'digitalSignature' must be allowed by CMP signer certificates.

OSSL_CMP_OPT_PERMIT_TA_IN_EXTRACERTS_FOR_IR

    Allow retrieving a trust anchor from extraCerts and using that
    to validate the certificate chain of an IP message.
    This is a quirk option added to support 3GPP TS 33.310.

    Note that using this option is dangerous as the certificate obtained
    this way has not been authenticated (at least not at CMP level).
    Taking it over as a trust anchor implements trust-on-first-use (TOFU).

OSSL_CMP_OPT_NO_CACHE_EXTRACERTS

    Do not cache certificates received in the extraCerts CMP message field.
    Otherwise they are stored to potentially help validate further messages.

OSSL_CMP_CTX_get_option() reads the current value of the given option (e.g., OSSL_CMP_OPT_IMPLICIT_CONFIRM) from the given OSSL_CMP_CTX structure.

OSSL_CMP_CTX_set_log_cb() sets in ctx the callback function cb for handling error queue entries and logging messages. When cb is NULL errors are printed to STDERR (if available, else ignored) any log messages are ignored. Alternatively, OSSL_CMP_log_open(3) may be used to direct logging to STDOUT.

OSSL_CMP_CTX_set_log_verbosity() is a macro setting the OSSL_CMP_OPT_LOG_VERBOSITY context option to the given level.

OSSL_CMP_CTX_print_errors() outputs any entries in the OpenSSL error queue. It is similar to ERR_print_errors_cb(3) but uses the CMP log callback function if set in the ctx for uniformity with CMP logging if given. Otherwise it uses ERR_print_errors(3) to print to STDERR (unless OPENSSL_NO_STDIO is defined).

OSSL_CMP_CTX_set1_serverPath() sets the HTTP path of the CMP server on the host, also known as "CMP alias". The default is /.

OSSL_CMP_CTX_set1_server() sets the given server address (which may be a hostname or IP address or NULL) in the given ctx.

OSSL_CMP_CTX_set_serverPort() sets the port of the CMP server to connect to. If not used or the port argument is 0 the default port applies, which is 80 for HTTP and 443 for HTTPS.

OSSL_CMP_CTX_set1_proxy() sets the HTTP proxy to be used for connecting to the given CMP server unless overruled by any "no_proxy" settings (see below). If TLS is not used this defaults to the value of the environment variable http_proxy if set, else HTTP_PROXY. Otherwise defaults to the value of https_proxy if set, else HTTPS_PROXY. An empty proxy string specifies not to use a proxy. Otherwise the format is [http[s]://][userinfo@]host[:port][/path][?query][#fragment], where any given userinfo, path, query, and fragment is ignored. If the host string is an IPv6 address, it must be enclosed in [ and ]. The default port number is 80, or 443 in case https: is given.

OSSL_CMP_CTX_set1_no_proxy() sets the list of server hostnames not to use an HTTP proxy for. The names may be separated by commas and/or whitespace. Defaults to the environment variable no_proxy if set, else NO_PROXY.

OSSL_CMP_CTX_set_http_cb() sets the optional BIO connect/disconnect callback function, which has the prototype

typedef BIO *(*HTTP_bio_cb_t) (BIO *bio, void *arg, int connect, int detail);

The callback may modify the bio provided by OSSL_CMP_MSG_http_perform(3) as described for the bio_update_fn parameter of OSSL_HTTP_open(3). The callback may make use of a custom defined argument arg, as described for the arg parameter of OSSL_HTTP_open(3). The argument is stored in the OSSL_CMP_CTX using OSSL_CMP_CTX_set_http_cb_arg(). See also the OSSL_CMP_OPT_USE_TLS option described above.

OSSL_CMP_CTX_set_http_cb_arg() sets the argument, respectively a pointer to a structure containing arguments such as an SSL_CTX structure, optionally to be used by the http connect/disconnect callback function. arg is not consumed, and it must therefore explicitly be freed when not needed any more. arg may be NULL to clear the entry.

OSSL_CMP_CTX_get_http_cb_arg() gets the argument, respectively the pointer to a structure containing arguments, previously set by OSSL_CMP_CTX_set_http_cb_arg() or NULL if unset.

OSSL_CMP_CTX_set_transfer_cb() sets the message transfer callback function, which has the type

typedef OSSL_CMP_MSG *(*OSSL_CMP_transfer_cb_t) (OSSL_CMP_CTX *ctx,
                                                 const OSSL_CMP_MSG *req);

Default is NULL, which implies the use of OSSL_CMP_MSG_http_perform(3). The callback should send the CMP request message it obtains via the req parameter and on success return the response, else it must return NULL. The transfer callback may make use of a custom defined argument stored in the ctx by means of OSSL_CMP_CTX_set_transfer_cb_arg(), which may be retrieved again through OSSL_CMP_CTX_get_transfer_cb_arg().

OSSL_CMP_CTX_set_transfer_cb_arg() sets an argument, respectively a pointer to a structure containing arguments, optionally to be used by the transfer callback. arg is not consumed, and it must therefore explicitly be freed when not needed any more. arg may be NULL to clear the entry.

OSSL_CMP_CTX_get_transfer_cb_arg() gets the argument, respectively the pointer to a structure containing arguments, previously set by OSSL_CMP_CTX_set_transfer_cb_arg() or NULL if unset.

OSSL_CMP_CTX_set1_srvCert() sets the expected server cert in ctx and trusts it directly (even if it is expired) when verifying signed response messages. This pins the accepted CMP server and results in ignoring whatever may be set using OSSL_CMP_CTX_set0_trusted(). Any previously set value is freed. The cert argument may be NULL to clear the entry. If set, the subject of the certificate is also used as default value for the recipient of CMP requests and as default value for the expected sender of CMP responses.

OSSL_CMP_CTX_set1_expected_sender() sets the Distinguished Name (DN) expected in the sender field of incoming CMP messages. Defaults to the subject of the pinned server certificate, if any. This can be used to make sure that only a particular entity is accepted as CMP message signer, and attackers are not able to use arbitrary certificates of a trusted PKI hierarchy to fraudulently pose as CMP server. Note that this gives slightly more freedom than OSSL_CMP_CTX_set1_srvCert(), which pins the server to the holder of a particular certificate, while the expected sender name will continue to match after updates of the server cert.

OSSL_CMP_CTX_set0_trusted() is an alias of the original OSSL_CMP_CTX_set0_trustedStore(). It sets in the CMP context ctx the certificate store of type X509_STORE containing trusted certificates, typically of root CAs. This is ignored when a certificate is pinned using OSSL_CMP_CTX_set1_srvCert(). The store may also hold CRLs and a certificate verification callback function used for signature-based peer authentication. Any store entry already set before is freed. When given a NULL parameter the entry is cleared.

OSSL_CMP_CTX_get0_trusted() is an alias of the original OSSL_CMP_CTX_get0_trustedStore(). It extracts from the CMP context ctx the pointer to the currently set certificate store containing trust anchors etc., or an empty store if unset.

OSSL_CMP_CTX_set1_untrusted() sets up a list of non-trusted certificates of intermediate CAs that may be useful for path construction for the own CMP signer certificate, for the own TLS certificate (if any), when verifying peer CMP protection certificates, and when verifying newly enrolled certificates. The reference counts of those certificates handled successfully are increased. This list of untrusted certificates in ctx will get augmented by extraCerts in received CMP messages unless OSSL_CMP_OPT_NO_CACHE_EXTRACERTS is set.

OSSL_CMP_CTX_get0_untrusted() returns a pointer to the list of untrusted certs in ctx, which may be empty if unset.

OSSL_CMP_CTX_set1_cert() sets the CMP signer certificate, also called protection certificate, related to the private key used for signature-based CMP message protection. Therefore the public key of this cert must correspond to the private key set before or thereafter via OSSL_CMP_CTX_set1_pkey(). When using signature-based protection of CMP request messages this CMP signer certificate will be included first in the extraCerts field. It serves as fallback reference certificate, see OSSL_CMP_CTX_set1_oldCert(). The subject of this cert will be used as the sender field of outgoing messages, while the subject of any cert set via OSSL_CMP_CTX_set1_oldCert(), the subject of any PKCS#10 CSR set via OSSL_CMP_CTX_set1_p10CSR(), and any value set via OSSL_CMP_CTX_set1_subjectName() are used as fallback.

The cert argument may be NULL to clear the entry.

OSSL_CMP_CTX_build_cert_chain() builds a certificate chain for the CMP signer certificate previously set in the ctx. It adds the optional candidates, a list of intermediate CA certs that may already constitute the targeted chain, to the untrusted certs that may already exist in the ctx. Then the function uses this augmented set of certs for chain construction. If own_trusted is NULL it builds the chain as far down as possible and ignores any verification errors. Else the CMP signer certificate must be verifiable where the chain reaches a trust anchor contained in own_trusted. On success the function stores the resulting chain in ctx for inclusion in the extraCerts field of signature-protected messages. Calling this function is optional; by default a chain construction is performed on demand that is equivalent to calling this function with the candidates and own_trusted arguments being NULL.

OSSL_CMP_CTX_set1_pkey() sets the client's private key corresponding to the CMP signer certificate set via OSSL_CMP_CTX_set1_cert(). This key is used create signature-based protection (protectionAlg = MSG_SIG_ALG) of outgoing messages unless a symmetric secret has been set via OSSL_CMP_CTX_set1_secretValue(). The pkey argument may be NULL to clear the entry.

OSSL_CMP_CTX_set1_secretValue() sets in ctx the byte string sec of length len to use as pre-shared secret, or clears it if the sec argument is NULL. If present, this secret is used to create MAC-based authentication and integrity protection (rather than applying signature-based protection) of outgoing messages and to verify authenticity and integrity of incoming messages that have MAC-based protection (protectionAlg = MSG_MAC_ALG).

OSSL_CMP_CTX_set1_referenceValue() sets the given referenceValue ref with length len in the given ctx or clears it if the ref argument is NULL. According to RFC 4210 section 5.1.1, if no value for the sender field in CMP message headers can be determined (i.e., no CMP signer certificate and no subject DN is set via OSSL_CMP_CTX_set1_subjectName() then the sender field will contain the NULL-DN and the senderKID field of the CMP message header must be set. When signature-based protection is used the sen