Provided by: libssl-doc_3.0.13-0ubuntu3.5_all bug

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>.

3.0.13                                             2025-02-05                             OSSL_CMP_CTX_NEW(3SSL)