Provided by: libssl-doc_3.0.13-0ubuntu3.4_all 
NAME
OSSL_CMP_CTX_new, OSSL_CMP_CTX_free, OSSL_CMP_CTX_reinit, 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_trustedStore,
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_set1_extraCertsOut,
OSSL_CMP_CTX_set0_newPkey, OSSL_CMP_CTX_get0_newPkey, OSSL_CMP_CTX_set1_issuer,
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_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);
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);
int OSSL_CMP_CTX_set0_trustedStore(OSSL_CMP_CTX *ctx, X509_STORE *store);
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);
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_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_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.
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_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_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<WARNING:> 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<WARNING:> 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.
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. Else the format is
"[http[s]://]address[:port][/path]", where any path given is ignored. 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 *ctx, int connect, int detail);
The callback may modify the bio provided by OSSL_CMP_MSG_http_perform(3), whereby it may
make use of a custom defined argument ctx stored in the OSSL_CMP_CTX by means of
OSSL_CMP_CTX_set_http_cb_arg(). During connection establishment, just after calling
BIO_do_connect_retry(), the function is invoked with the connect argument being 1 and the
detail argument being 1 if HTTPS is requested, i.e., SSL/TLS should be enabled. On
disconnect connect is 0 and detail is 1 in case no error occurred, else 0. For instance,
on connect the function may prepend a TLS BIO to implement HTTPS; after disconnect it may
do some diagnostic output and/or specific cleanup. The function should return NULL to
indicate failure. After disconnect the modified BIO will be deallocated using
BIO_free_all().
OSSL_CMP_CTX_set_http_cb_arg() sets an argument, respectively a pointer to a structure
containing arguments, 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);
Returns 1 on success, 0 on error.
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_trustedStore(). 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_trustedStore() 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_trustedStore() 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.
OSSL_CMP_CTX_get0_untrusted(OSSL_CMP_CTX *ctx) returns a pointer to the list of untrusted
certs, 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 for signature-based 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() 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 senderKID will be set to
the subjectKeyIdentifier of the CMP signer certificate as far as present. If not present
or when MAC-based protection is used the ref value is taken as the fallback value for the
senderKID.
OSSL_CMP_CTX_set1_recipient() sets the recipient name that will be used in the PKIHeader
of CMP request messages, i.e. the X509 name of the (CA) server.
The recipient field in the header of a CMP message is mandatory. If not given explicitly
the recipient is determined in the following order: the subject of the CMP server
certificate set using OSSL_CMP_CTX_set1_srvCert(), the value set using
OSSL_CMP_CTX_set1_issuer(), the issuer of the certificate set using
OSSL_CMP_CTX_set1_oldCert(), the issuer of the CMP signer certificate, as far as any of
those is present, else the NULL-DN as last resort.
OSSL_CMP_CTX_push0_geninfo_ITAV() adds itav to the stack in the ctx to be added to the
GeneralInfo field of the CMP PKIMessage header of a request message sent with this
context.
OSSL_CMP_CTX_reset_geninfo_ITAVs() clears any ITAVs that were added by
OSSL_CMP_CTX_push0_geninfo_ITAV().
OSSL_CMP_CTX_set1_extraCertsOut() sets the stack of extraCerts that will be sent to
remote.
OSSL_CMP_CTX_set0_newPkey() can be used to explicitly set the given EVP_PKEY structure as
the private or public key to be certified in the CMP context. The priv parameter must be
0 if and only if the given key is a public key.
OSSL_CMP_CTX_get0_newPkey() gives the key to use for certificate enrollment dependent on
fields of the CMP context structure: the newPkey (which may be a private or public key) if
present, else the public key in the p10CSR if present, else the client's private key. If
the priv parameter is not 0 and the selected key does not have a private component then
NULL is returned.
OSSL_CMP_CTX_set1_issuer() sets the name of the intended issuer that will be set in the
CertTemplate, i.e., the X509 name of the CA server.
OSSL_CMP_CTX_set1_subjectName() sets the subject DN that will be used in the CertTemplate
structure when requesting a new cert. For Key Update Requests (KUR), it defaults to the
subject DN of the reference certificate, see OSSL_CMP_CTX_set1_oldCert(). This default is
used for Initialization Requests (IR) and Certification Requests (CR) only if no SANs are
set. The subjectName is also used as fallback for the sender field of outgoing CMP
messages if no reference certificate is available.
OSSL_CMP_CTX_push1_subjectAltName() adds the given X509 name to the list of alternate
names on the certificate template request. This cannot be used if any Subject Alternative
Name extension is set via OSSL_CMP_CTX_set0_reqExtensions(). By default, unless
OSSL_CMP_OPT_SUBJECTALTNAME_NODEFAULT has been set, the Subject Alternative Names are
copied from the reference certificate, see OSSL_CMP_CTX_set1_oldCert(). If set and the
subject DN is not set with OSSL_CMP_CTX_set1_subjectName() then the certificate template
of an IR and CR will not be filled with the default subject DN from the reference
certificate. If a subject DN is desired it needs to be set explicitly with
OSSL_CMP_CTX_set1_subjectName().
OSSL_CMP_CTX_set0_reqExtensions() sets the X.509v3 extensions to be used in IR/CR/KUR.
OSSL_CMP_CTX_reqExtensions_have_SAN() returns 1 if the context contains a Subject
Alternative Name extension, else 0 or -1 on error.
OSSL_CMP_CTX_push0_policy() adds the certificate policy info object to the X509_EXTENSIONS
of the requested certificate template.
OSSL_CMP_CTX_set1_oldCert() sets the old certificate to be updated in Key Update Requests
(KUR) or to be revoked in Revocation Requests (RR). It must be given for RR, else it
defaults to the CMP signer certificate. The reference certificate determined in this way,
if any, is also used for deriving default subject DN, public key, Subject Alternative
Names, and the default issuer entry in the requested certificate template of IR/CR/KUR.
The subject of the reference certificate is used as the sender field value in CMP message
headers. Its issuer is used as default recipient in CMP message headers.
OSSL_CMP_CTX_set1_p10CSR() sets the PKCS#10 CSR to use in P10CR messages. If such a CSR
is provided, its subject, public key, and extension fields are also used as fallback
values for the certificate template of IR/CR/KUR messages.
OSSL_CMP_CTX_push0_genm_ITAV() adds itav to the stack in the ctx which will be the body of
a General Message sent with this context.
OSSL_CMP_certConf_cb() is the default certificate confirmation callback function. If the
callback argument is not NULL it must point to a trust store. In this case the function
checks that the newly enrolled certificate can be verified using this trust store and
untrusted certificates from the ctx, which have been augmented by the list of extraCerts
received. During this verification, any certificate status checking is disabled. If the
callback argument is NULL the function tries building an approximate chain as far as
possible using the same untrusted certificates from the ctx, and if this fails it takes
the received extraCerts as fallback. The resulting cert chain can be retrieved using
OSSL_CMP_CTX_get1_newChain().
OSSL_CMP_CTX_set_certConf_cb() sets the callback used for evaluating the newly enrolled
certificate before the library sends, depending on its result, a positive or negative
certConf message to the server. The callback has type
typedef int (*OSSL_CMP_certConf_cb_t) (OSSL_CMP_CTX *ctx, X509 *cert,
int fail_info, const char **txt);
and should inspect the certificate it obtains via the cert parameter and may overrule the
pre-decision given in the fail_info and *txt parameters. If it accepts the certificate it
must return 0, indicating success. Else it must return a bit field reflecting
PKIFailureInfo with at least one failure bit and may set the *txt output parameter to
point to a string constant with more detail. The transfer callback may make use of a
custom defined argument stored in the ctx by means of OSSL_CMP_CTX_set_certConf_cb_arg(),
which may be retrieved again through OSSL_CMP_CTX_get_certConf_cb_arg(). Typically, the
callback will check at least that the certificate can be verified using a set of trusted
certificates. It also could compare the subject DN and other fields of the newly enrolled
certificate with the certificate template of the request.
OSSL_CMP_CTX_set_certConf_cb_arg() sets an argument, respectively a pointer to a structure
containing arguments, optionally to be used by the certConf 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_certConf_cb_arg() gets the argument, respectively the pointer to a
structure containing arguments, previously set by OSSL_CMP_CTX_set_certConf_cb_arg(), or
NULL if unset.
OSSL_CMP_CTX_get_status() returns for client contexts the PKIstatus from the last received
CertRepMessage or Revocation Response or error message: =item OSSL_CMP_PKISTATUS_accepted
on successful receipt of a GENP message:
OSSL_CMP_PKISTATUS_request
if an IR/CR/KUR/RR/GENM request message could not be produced,
OSSL_CMP_PKISTATUS_trans
on a transmission error or transaction error for this type of request, and
OSSL_CMP_PKISTATUS_unspecified
if no such request was attempted or OSSL_CMP_CTX_reinit() has been called.
For server contexts it returns OSSL_CMP_PKISTATUS_trans if a transaction is open,
otherwise OSSL_CMP_PKISTATUS_unspecified.
OSSL_CMP_CTX_get0_statusString() returns the statusString from the last received
CertRepMessage or Revocation Response or error message, or NULL if unset.
OSSL_CMP_CTX_get_failInfoCode() returns the error code from the failInfo field of the last
received CertRepMessage or Revocation Response or error message, or -1 if no such response
was received or OSSL_CMP_CTX_reinit() has been called. This is a bit field and the flags
for it are specified in the header file <openssl/cmp.h>. The flags start with
OSSL_CMP_CTX_FAILINFO, for example: OSSL_CMP_CTX_FAILINFO_badAlg. Returns -1 if the
failInfoCode field is unset.
OSSL_CMP_CTX_get0_newCert() returns the pointer to the newly obtained certificate in case
it is available, else NULL.
OSSL_CMP_CTX_get1_newChain() returns a pointer to a duplicate of the stack of X.509
certificates computed by OSSL_CMP_certConf_cb() (if this function has been called) on the
last received certificate response message IP/CP/KUP.
OSSL_CMP_CTX_get1_caPubs() returns a pointer to a duplicate of the list of X.509
certificates in the caPubs field of the last received certificate response message (of
type IP, CP, or KUP), or an empty stack if no caPubs have been received in the current
transaction.
OSSL_CMP_CTX_get1_extraCertsIn() returns a pointer to a duplicate of the list of X.509
certificates contained in the extraCerts field of the last received response message
(except for pollRep and PKIConf), or an empty stack if no extraCerts have been received in
the current transaction.
OSSL_CMP_CTX_set1_transactionID() sets the given transaction ID in the given OSSL_CMP_CTX
structure.
OSSL_CMP_CTX_set1_senderNonce() stores the last sent sender nonce in the ctx. This will be
used to validate the recipNonce in incoming messages.
NOTES
CMP is defined in RFC 4210 (and CRMF in RFC 4211).
RETURN VALUES
OSSL_CMP_CTX_free() and OSSL_CMP_CTX_print_errors() do not return anything.
OSSL_CMP_CTX_new(), OSSL_CMP_CTX_get_http_cb_arg(), OSSL_CMP_CTX_get_transfer_cb_arg(),
OSSL_CMP_CTX_get0_trustedStore(), OSSL_CMP_CTX_get0_untrusted(),
OSSL_CMP_CTX_get0_newPkey(), OSSL_CMP_CTX_get_certConf_cb_arg(),
OSSL_CMP_CTX_get0_statusString(), OSSL_CMP_CTX_get0_newCert(),
OSSL_CMP_CTX_get0_newChain(), OSSL_CMP_CTX_get1_caPubs(), and
OSSL_CMP_CTX_get1_extraCertsIn() return the intended pointer value as described above or
NULL on error.
OSSL_CMP_CTX_get_option(), OSSL_CMP_CTX_reqExtensions_have_SAN(),
OSSL_CMP_CTX_get_status(), and OSSL_CMP_CTX_get_failInfoCode() return the intended value
as described above or -1 on error.
OSSL_CMP_certConf_cb() returns fail_info if it is not equal to 0, else 0 on successful
validation, or else a bit field with the OSSL_CMP_PKIFAILUREINFO_incorrectData bit set.
All other functions, including OSSL_CMP_CTX_reinit() and
OSSL_CMP_CTX_reset_geninfo_ITAVs(), return 1 on success, 0 on error.
EXAMPLES
The following code omits error handling.
Set up a CMP client context for sending requests and verifying responses:
cmp_ctx = OSSL_CMP_CTX_new();
OSSL_CMP_CTX_set1_server(cmp_ctx, name_or_address);
OSSL_CMP_CTX_set1_serverPort(cmp_ctx, port_string);
OSSL_CMP_CTX_set1_serverPath(cmp_ctx, path_or_alias);
OSSL_CMP_CTX_set0_trustedStore(cmp_ctx, ts);
Set up symmetric credentials for MAC-based message protection such as PBM:
OSSL_CMP_CTX_set1_referenceValue(cmp_ctx, ref, ref_len);
OSSL_CMP_CTX_set1_secretValue(cmp_ctx, sec, sec_len);
Set up the details for certificate requests:
OSSL_CMP_CTX_set1_subjectName(cmp_ctx, name);
OSSL_CMP_CTX_set0_newPkey(cmp_ctx, 1, initialKey);
Perform an Initialization Request transaction:
initialCert = OSSL_CMP_exec_IR_ses(cmp_ctx);
Reset the transaction state of the CMP context and the credentials:
OSSL_CMP_CTX_reinit(cmp_ctx);
OSSL_CMP_CTX_set1_referenceValue(cmp_ctx, NULL, 0);
OSSL_CMP_CTX_set1_secretValue(cmp_ctx, NULL, 0);
Perform a Certification Request transaction, making use of the new credentials:
OSSL_CMP_CTX_set1_cert(cmp_ctx, initialCert);
OSSL_CMP_CTX_set1_pkey(cmp_ctx, initialKey);
OSSL_CMP_CTX_set0_newPkey(cmp_ctx, 1, curentKey);
currentCert = OSSL_CMP_exec_CR_ses(cmp_ctx);
Perform a Key Update Request, signed using the cert (and key) to be updated:
OSSL_CMP_CTX_reinit(cmp_ctx);
OSSL_CMP_CTX_set1_cert(cmp_ctx, currentCert);
OSSL_CMP_CTX_set1_pkey(cmp_ctx, currentKey);
OSSL_CMP_CTX_set0_newPkey(cmp_ctx, 1, updatedKey);
currentCert = OSSL_CMP_exec_KUR_ses(cmp_ctx);
currentKey = updatedKey;
Perform a General Message transaction including, as an example, the id-it-signKeyPairTypes
OID and prints info on the General Response contents:
OSSL_CMP_CTX_reinit(cmp_ctx);
ASN1_OBJECT *type = OBJ_txt2obj("1.3.6.1.5.5.7.4.2", 1);
OSSL_CMP_ITAV *itav = OSSL_CMP_ITAV_create(type, NULL);
OSSL_CMP_CTX_push0_genm_ITAV(cmp_ctx, itav);
STACK_OF(OSSL_CMP_ITAV) *itavs;
itavs = OSSL_CMP_exec_GENM_ses(cmp_ctx);
print_itavs(itavs);
sk_OSSL_CMP_ITAV_pop_free(itavs, OSSL_CMP_ITAV_free);
SEE ALSO
OSSL_CMP_exec_IR_ses(3), OSSL_CMP_exec_CR_ses(3), OSSL_CMP_exec_KUR_ses(3),
OSSL_CMP_exec_GENM_ses(3), OSSL_CMP_exec_certreq(3), OSSL_CMP_MSG_http_perform(3),
ERR_print_errors_cb(3)
HISTORY
The OpenSSL CMP support was added in OpenSSL 3.0.
OSSL_CMP_CTX_reset_geninfo_ITAVs() was added in OpenSSL 3.0.8.
COPYRIGHT
Copyright 2007-2023 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>.