1=pod 2 3=head1 NAME 4 5OSSL_CMP_CTX_new, 6OSSL_CMP_CTX_free, 7OSSL_CMP_CTX_reinit, 8OSSL_CMP_CTX_set_option, 9OSSL_CMP_CTX_get_option, 10OSSL_CMP_CTX_set_log_cb, 11OSSL_CMP_CTX_set_log_verbosity, 12OSSL_CMP_CTX_print_errors, 13OSSL_CMP_CTX_set1_serverPath, 14OSSL_CMP_CTX_set1_server, 15OSSL_CMP_CTX_set_serverPort, 16OSSL_CMP_CTX_set1_proxy, 17OSSL_CMP_CTX_set1_no_proxy, 18OSSL_CMP_CTX_set_http_cb, 19OSSL_CMP_CTX_set_http_cb_arg, 20OSSL_CMP_CTX_get_http_cb_arg, 21OSSL_CMP_transfer_cb_t, 22OSSL_CMP_CTX_set_transfer_cb, 23OSSL_CMP_CTX_set_transfer_cb_arg, 24OSSL_CMP_CTX_get_transfer_cb_arg, 25OSSL_CMP_CTX_set1_srvCert, 26OSSL_CMP_CTX_set1_expected_sender, 27OSSL_CMP_CTX_set0_trustedStore, 28OSSL_CMP_CTX_get0_trustedStore, 29OSSL_CMP_CTX_set1_untrusted, 30OSSL_CMP_CTX_get0_untrusted, 31OSSL_CMP_CTX_set1_cert, 32OSSL_CMP_CTX_build_cert_chain, 33OSSL_CMP_CTX_set1_pkey, 34OSSL_CMP_CTX_set1_referenceValue, 35OSSL_CMP_CTX_set1_secretValue, 36OSSL_CMP_CTX_set1_recipient, 37OSSL_CMP_CTX_push0_geninfo_ITAV, 38OSSL_CMP_CTX_reset_geninfo_ITAVs, 39OSSL_CMP_CTX_set1_extraCertsOut, 40OSSL_CMP_CTX_set0_newPkey, 41OSSL_CMP_CTX_get0_newPkey, 42OSSL_CMP_CTX_set1_issuer, 43OSSL_CMP_CTX_set1_subjectName, 44OSSL_CMP_CTX_push1_subjectAltName, 45OSSL_CMP_CTX_set0_reqExtensions, 46OSSL_CMP_CTX_reqExtensions_have_SAN, 47OSSL_CMP_CTX_push0_policy, 48OSSL_CMP_CTX_set1_oldCert, 49OSSL_CMP_CTX_set1_p10CSR, 50OSSL_CMP_CTX_push0_genm_ITAV, 51OSSL_CMP_certConf_cb_t, 52OSSL_CMP_certConf_cb, 53OSSL_CMP_CTX_set_certConf_cb, 54OSSL_CMP_CTX_set_certConf_cb_arg, 55OSSL_CMP_CTX_get_certConf_cb_arg, 56OSSL_CMP_CTX_get_status, 57OSSL_CMP_CTX_get0_statusString, 58OSSL_CMP_CTX_get_failInfoCode, 59OSSL_CMP_CTX_get0_newCert, 60OSSL_CMP_CTX_get1_newChain, 61OSSL_CMP_CTX_get1_caPubs, 62OSSL_CMP_CTX_get1_extraCertsIn, 63OSSL_CMP_CTX_set1_transactionID, 64OSSL_CMP_CTX_set1_senderNonce 65- functions for managing the CMP client context data structure 66 67=head1 SYNOPSIS 68 69 #include <openssl/cmp.h> 70 71 OSSL_CMP_CTX *OSSL_CMP_CTX_new(OSSL_LIB_CTX *libctx, const char *propq); 72 void OSSL_CMP_CTX_free(OSSL_CMP_CTX *ctx); 73 int OSSL_CMP_CTX_reinit(OSSL_CMP_CTX *ctx); 74 int OSSL_CMP_CTX_set_option(OSSL_CMP_CTX *ctx, int opt, int val); 75 int OSSL_CMP_CTX_get_option(const OSSL_CMP_CTX *ctx, int opt); 76 77 /* logging and error reporting: */ 78 int OSSL_CMP_CTX_set_log_cb(OSSL_CMP_CTX *ctx, OSSL_CMP_log_cb_t cb); 79 #define OSSL_CMP_CTX_set_log_verbosity(ctx, level) 80 void OSSL_CMP_CTX_print_errors(const OSSL_CMP_CTX *ctx); 81 82 /* message transfer: */ 83 int OSSL_CMP_CTX_set1_serverPath(OSSL_CMP_CTX *ctx, const char *path); 84 int OSSL_CMP_CTX_set1_server(OSSL_CMP_CTX *ctx, const char *address); 85 int OSSL_CMP_CTX_set_serverPort(OSSL_CMP_CTX *ctx, int port); 86 int OSSL_CMP_CTX_set1_proxy(OSSL_CMP_CTX *ctx, const char *name); 87 int OSSL_CMP_CTX_set1_no_proxy(OSSL_CMP_CTX *ctx, const char *names); 88 int OSSL_CMP_CTX_set_http_cb(OSSL_CMP_CTX *ctx, HTTP_bio_cb_t cb); 89 int OSSL_CMP_CTX_set_http_cb_arg(OSSL_CMP_CTX *ctx, void *arg); 90 void *OSSL_CMP_CTX_get_http_cb_arg(const OSSL_CMP_CTX *ctx); 91 typedef OSSL_CMP_MSG *(*OSSL_CMP_transfer_cb_t)(OSSL_CMP_CTX *ctx, 92 const OSSL_CMP_MSG *req); 93 int OSSL_CMP_CTX_set_transfer_cb(OSSL_CMP_CTX *ctx, 94 OSSL_CMP_transfer_cb_t cb); 95 int OSSL_CMP_CTX_set_transfer_cb_arg(OSSL_CMP_CTX *ctx, void *arg); 96 void *OSSL_CMP_CTX_get_transfer_cb_arg(const OSSL_CMP_CTX *ctx); 97 98 /* server authentication: */ 99 int OSSL_CMP_CTX_set1_srvCert(OSSL_CMP_CTX *ctx, X509 *cert); 100 int OSSL_CMP_CTX_set1_expected_sender(OSSL_CMP_CTX *ctx, 101 const X509_NAME *name); 102 int OSSL_CMP_CTX_set0_trustedStore(OSSL_CMP_CTX *ctx, X509_STORE *store); 103 X509_STORE *OSSL_CMP_CTX_get0_trustedStore(const OSSL_CMP_CTX *ctx); 104 int OSSL_CMP_CTX_set1_untrusted(OSSL_CMP_CTX *ctx, STACK_OF(X509) *certs); 105 STACK_OF(X509) *OSSL_CMP_CTX_get0_untrusted(const OSSL_CMP_CTX *ctx); 106 107 /* client authentication: */ 108 int OSSL_CMP_CTX_set1_cert(OSSL_CMP_CTX *ctx, X509 *cert); 109 int OSSL_CMP_CTX_build_cert_chain(OSSL_CMP_CTX *ctx, X509_STORE *own_trusted, 110 STACK_OF(X509) *candidates); 111 int OSSL_CMP_CTX_set1_pkey(OSSL_CMP_CTX *ctx, EVP_PKEY *pkey); 112 int OSSL_CMP_CTX_set1_referenceValue(OSSL_CMP_CTX *ctx, 113 const unsigned char *ref, int len); 114 int OSSL_CMP_CTX_set1_secretValue(OSSL_CMP_CTX *ctx, 115 const unsigned char *sec, int len); 116 117 /* CMP message header and extra certificates: */ 118 int OSSL_CMP_CTX_set1_recipient(OSSL_CMP_CTX *ctx, const X509_NAME *name); 119 int OSSL_CMP_CTX_push0_geninfo_ITAV(OSSL_CMP_CTX *ctx, OSSL_CMP_ITAV *itav); 120 int OSSL_CMP_CTX_reset_geninfo_ITAVs(OSSL_CMP_CTX *ctx); 121 int OSSL_CMP_CTX_set1_extraCertsOut(OSSL_CMP_CTX *ctx, 122 STACK_OF(X509) *extraCertsOut); 123 124 /* certificate template: */ 125 int OSSL_CMP_CTX_set0_newPkey(OSSL_CMP_CTX *ctx, int priv, EVP_PKEY *pkey); 126 EVP_PKEY *OSSL_CMP_CTX_get0_newPkey(const OSSL_CMP_CTX *ctx, int priv); 127 int OSSL_CMP_CTX_set1_issuer(OSSL_CMP_CTX *ctx, const X509_NAME *name); 128 int OSSL_CMP_CTX_set1_subjectName(OSSL_CMP_CTX *ctx, const X509_NAME *name); 129 int OSSL_CMP_CTX_push1_subjectAltName(OSSL_CMP_CTX *ctx, 130 const GENERAL_NAME *name); 131 int OSSL_CMP_CTX_set0_reqExtensions(OSSL_CMP_CTX *ctx, X509_EXTENSIONS *exts); 132 int OSSL_CMP_CTX_reqExtensions_have_SAN(OSSL_CMP_CTX *ctx); 133 int OSSL_CMP_CTX_push0_policy(OSSL_CMP_CTX *ctx, POLICYINFO *pinfo); 134 int OSSL_CMP_CTX_set1_oldCert(OSSL_CMP_CTX *ctx, X509 *cert); 135 int OSSL_CMP_CTX_set1_p10CSR(OSSL_CMP_CTX *ctx, const X509_REQ *csr); 136 137 /* misc body contents: */ 138 int OSSL_CMP_CTX_push0_genm_ITAV(OSSL_CMP_CTX *ctx, OSSL_CMP_ITAV *itav); 139 140 /* certificate confirmation: */ 141 typedef int (*OSSL_CMP_certConf_cb_t)(OSSL_CMP_CTX *ctx, X509 *cert, 142 int fail_info, const char **txt); 143 int OSSL_CMP_certConf_cb(OSSL_CMP_CTX *ctx, X509 *cert, int fail_info, 144 const char **text); 145 int OSSL_CMP_CTX_set_certConf_cb(OSSL_CMP_CTX *ctx, OSSL_CMP_certConf_cb_t cb); 146 int OSSL_CMP_CTX_set_certConf_cb_arg(OSSL_CMP_CTX *ctx, void *arg); 147 void *OSSL_CMP_CTX_get_certConf_cb_arg(const OSSL_CMP_CTX *ctx); 148 149 /* result fetching: */ 150 int OSSL_CMP_CTX_get_status(const OSSL_CMP_CTX *ctx); 151 OSSL_CMP_PKIFREETEXT *OSSL_CMP_CTX_get0_statusString(const OSSL_CMP_CTX *ctx); 152 int OSSL_CMP_CTX_get_failInfoCode(const OSSL_CMP_CTX *ctx); 153 154 X509 *OSSL_CMP_CTX_get0_newCert(const OSSL_CMP_CTX *ctx); 155 STACK_OF(X509) *OSSL_CMP_CTX_get1_newChain(const OSSL_CMP_CTX *ctx); 156 STACK_OF(X509) *OSSL_CMP_CTX_get1_caPubs(const OSSL_CMP_CTX *ctx); 157 STACK_OF(X509) *OSSL_CMP_CTX_get1_extraCertsIn(const OSSL_CMP_CTX *ctx); 158 159 /* for testing and debugging purposes: */ 160 int OSSL_CMP_CTX_set1_transactionID(OSSL_CMP_CTX *ctx, 161 const ASN1_OCTET_STRING *id); 162 int OSSL_CMP_CTX_set1_senderNonce(OSSL_CMP_CTX *ctx, 163 const ASN1_OCTET_STRING *nonce); 164 165=head1 DESCRIPTION 166 167This is the context API for using CMP (Certificate Management Protocol) with 168OpenSSL. 169 170OSSL_CMP_CTX_new() allocates an B<OSSL_CMP_CTX> structure associated with 171the library context I<libctx> and property query string I<propq>, 172both of which may be NULL to select the defaults. 173It initializes the remaining fields to their default values - for instance, 174the logging verbosity is set to OSSL_CMP_LOG_INFO, 175the message timeout is set to 120 seconds, 176and the proof-of-possession method is set to OSSL_CRMF_POPO_SIGNATURE. 177 178OSSL_CMP_CTX_free() deallocates an OSSL_CMP_CTX structure. 179If the argument is NULL, nothing is done. 180 181OSSL_CMP_CTX_reinit() prepares the given I<ctx> for a further transaction by 182clearing the internal CMP transaction (aka session) status, PKIStatusInfo, 183and any previous results (newCert, newChain, caPubs, and extraCertsIn) 184from the last executed transaction. 185It also clears any ITAVs that were added by OSSL_CMP_CTX_push0_genm_ITAV(). 186All other field values (i.e., CMP options) are retained for potential reuse. 187 188OSSL_CMP_CTX_set_option() sets the given value for the given option 189(e.g., OSSL_CMP_OPT_IMPLICIT_CONFIRM) in the given OSSL_CMP_CTX structure. 190 191The following options can be set: 192 193=over 4 194 195=item B<OSSL_CMP_OPT_LOG_VERBOSITY> 196 197 The level of severity needed for actually outputting log messages 198 due to errors, warnings, general info, debugging, etc. 199 Default is OSSL_CMP_LOG_INFO. See also L<OSSL_CMP_log_open(3)>. 200 201=item B<OSSL_CMP_OPT_KEEP_ALIVE> 202 203 If the given value is 0 then HTTP connections are not kept open 204 after receiving a response, which is the default behavior for HTTP 1.0. 205 If the value is 1 or 2 then persistent connections are requested. 206 If the value is 2 then persistent connections are required, 207 i.e., in case the server does not grant them an error occurs. 208 The default value is 1: prefer to keep the connection open. 209 210=item B<OSSL_CMP_OPT_MSG_TIMEOUT> 211 212 Number of seconds a CMP request-response message round trip 213 is allowed to take before a timeout error is returned. 214 A value <= 0 means no limitation (waiting indefinitely). 215 Default is to use the B<OSSL_CMP_OPT_TOTAL_TIMEOUT> setting. 216 217=item B<OSSL_CMP_OPT_TOTAL_TIMEOUT> 218 219 Maximum total number of seconds a transaction may take, 220 including polling etc. 221 A value <= 0 means no limitation (waiting indefinitely). 222 Default is 0. 223 224=item B<OSSL_CMP_OPT_VALIDITY_DAYS> 225 226 Number of days new certificates are asked to be valid for. 227 228=item B<OSSL_CMP_OPT_SUBJECTALTNAME_NODEFAULT> 229 230 Do not take default Subject Alternative Names 231 from the reference certificate. 232 233=item B<OSSL_CMP_OPT_SUBJECTALTNAME_CRITICAL> 234 235 Demand that the given Subject Alternative Names are flagged as critical. 236 237=item B<OSSL_CMP_OPT_POLICIES_CRITICAL> 238 239 Demand that the given policies are flagged as critical. 240 241=item B<OSSL_CMP_OPT_POPO_METHOD> 242 243 Select the proof of possession method to use. Possible values are: 244 245 OSSL_CRMF_POPO_NONE - ProofOfPossession field omitted 246 OSSL_CRMF_POPO_RAVERIFIED - assert that the RA has already 247 verified the PoPo 248 OSSL_CRMF_POPO_SIGNATURE - sign a value with private key, 249 which is the default. 250 OSSL_CRMF_POPO_KEYENC - decrypt the encrypted certificate 251 ("indirect method") 252 253 Note that a signature-based POPO can only be produced if a private key 254 is provided as the newPkey or client's pkey component of the CMP context. 255 256=item B<OSSL_CMP_OPT_DIGEST_ALGNID> 257 258 The NID of the digest algorithm to be used in RFC 4210's MSG_SIG_ALG 259 for signature-based message protection and Proof-of-Possession (POPO). 260 Default is SHA256. 261 262=item B<OSSL_CMP_OPT_OWF_ALGNID> 263 The NID of the digest algorithm to be used as one-way function (OWF) 264 for MAC-based message protection with password-based MAC (PBM). 265 See RFC 4210 section 5.1.3.1 for details. 266 Default is SHA256. 267 268=item B<OSSL_CMP_OPT_MAC_ALGNID> 269 The NID of the MAC algorithm to be used for message protection with PBM. 270 Default is HMAC-SHA1 as per RFC 4210. 271 272=item B<OSSL_CMP_OPT_REVOCATION_REASON> 273 274 The reason code to be included in a Revocation Request (RR); 275 values: 0..10 (RFC 5210, 5.3.1) or -1 for none, which is the default. 276 277=item B<OSSL_CMP_OPT_IMPLICIT_CONFIRM> 278 279 Request server to enable implicit confirm mode, where the client 280 does not need to send confirmation upon receiving the 281 certificate. If the server does not enable implicit confirmation 282 in the return message, then confirmation is sent anyway. 283 284=item B<OSSL_CMP_OPT_DISABLE_CONFIRM> 285 286 Do not confirm enrolled certificates, to cope with broken servers 287 not supporting implicit confirmation correctly. 288B<WARNING:> This setting leads to unspecified behavior and it is meant 289exclusively to allow interoperability with server implementations violating 290RFC 4210. 291 292=item B<OSSL_CMP_OPT_UNPROTECTED_SEND> 293 294 Send request or response messages without CMP-level protection. 295 296=item B<OSSL_CMP_OPT_UNPROTECTED_ERRORS> 297 298 Accept unprotected error responses which are either explicitly 299 unprotected or where protection verification failed. Applies to regular 300 error messages as well as certificate responses (IP/CP/KUP) and 301 revocation responses (RP) with rejection. 302B<WARNING:> This setting leads to unspecified behavior and it is meant 303exclusively to allow interoperability with server implementations violating 304RFC 4210. 305 306=item B<OSSL_CMP_OPT_IGNORE_KEYUSAGE> 307 308 Ignore key usage restrictions in the signer's certificate when 309 validating signature-based protection in received CMP messages. 310 Else, 'digitalSignature' must be allowed by CMP signer certificates. 311 312=item B<OSSL_CMP_OPT_PERMIT_TA_IN_EXTRACERTS_FOR_IR> 313 314 Allow retrieving a trust anchor from extraCerts and using that 315 to validate the certificate chain of an IP message. 316 This is a quirk option added to support 3GPP TS 33.310. 317 318 Note that using this option is dangerous as the certificate obtained 319 this way has not been authenticated (at least not at CMP level). 320 Taking it over as a trust anchor implements trust-on-first-use (TOFU). 321 322=back 323 324OSSL_CMP_CTX_get_option() reads the current value of the given option 325(e.g., OSSL_CMP_OPT_IMPLICIT_CONFIRM) from the given OSSL_CMP_CTX structure. 326 327OSSL_CMP_CTX_set_log_cb() sets in I<ctx> the callback function I<cb> 328for handling error queue entries and logging messages. 329When I<cb> is NULL errors are printed to STDERR (if available, else ignored) 330any log messages are ignored. 331Alternatively, L<OSSL_CMP_log_open(3)> may be used to direct logging to STDOUT. 332 333OSSL_CMP_CTX_set_log_verbosity() is a macro setting the 334OSSL_CMP_OPT_LOG_VERBOSITY context option to the given level. 335 336OSSL_CMP_CTX_print_errors() outputs any entries in the OpenSSL error queue. It 337is similar to L<ERR_print_errors_cb(3)> but uses the CMP log callback function 338if set in the I<ctx> for uniformity with CMP logging if given. Otherwise it uses 339L<ERR_print_errors(3)> to print to STDERR (unless OPENSSL_NO_STDIO is defined). 340 341OSSL_CMP_CTX_set1_serverPath() sets the HTTP path of the CMP server on the host, 342also known as "CMP alias". 343The default is C</>. 344 345OSSL_CMP_CTX_set1_server() sets the given server I<address> 346(which may be a hostname or IP address or NULL) in the given I<ctx>. 347 348OSSL_CMP_CTX_set_serverPort() sets the port of the CMP server to connect to. 349If not used or the I<port> argument is 0 350the default port applies, which is 80 for HTTP and 443 for HTTPS. 351 352OSSL_CMP_CTX_set1_proxy() sets the HTTP proxy to be used for connecting to 353the given CMP server unless overruled by any "no_proxy" settings (see below). 354If TLS is not used this defaults to the value of 355the environment variable C<http_proxy> if set, else C<HTTP_PROXY>. 356Otherwise defaults to the value of C<https_proxy> if set, else C<HTTPS_PROXY>. 357An empty proxy string specifies not to use a proxy. 358Else the format is C<[http[s]://]address[:port][/path]>, 359where any path given is ignored. 360The default port number is 80, or 443 in case C<https:> is given. 361 362OSSL_CMP_CTX_set1_no_proxy() sets the list of server hostnames not to use 363an HTTP proxy for. The names may be separated by commas and/or whitespace. 364Defaults to the environment variable C<no_proxy> if set, else C<NO_PROXY>. 365 366OSSL_CMP_CTX_set_http_cb() sets the optional BIO connect/disconnect callback 367function, which has the prototype 368 369 typedef BIO *(*HTTP_bio_cb_t) (BIO *bio, void *ctx, int connect, int detail); 370 371The callback may modify the I<bio> provided by L<OSSL_CMP_MSG_http_perform(3)>, 372whereby it may make use of a custom defined argument I<ctx> 373stored in the OSSL_CMP_CTX by means of OSSL_CMP_CTX_set_http_cb_arg(). 374During connection establishment, just after calling BIO_do_connect_retry(), 375the function is invoked with the I<connect> argument being 1 and the I<detail> 376argument being 1 if HTTPS is requested, i.e., SSL/TLS should be enabled. On 377disconnect I<connect> is 0 and I<detail> is 1 in case no error occurred, else 0. 378For instance, on connect the function may prepend a TLS BIO to implement HTTPS; 379after disconnect it may do some diagnostic output and/or specific cleanup. 380The function should return NULL to indicate failure. 381After disconnect the modified BIO will be deallocated using BIO_free_all(). 382 383OSSL_CMP_CTX_set_http_cb_arg() sets an argument, respectively a pointer to 384a structure containing arguments, 385optionally to be used by the http connect/disconnect callback function. 386I<arg> is not consumed, and it must therefore explicitly be freed when not 387needed any more. I<arg> may be NULL to clear the entry. 388 389OSSL_CMP_CTX_get_http_cb_arg() gets the argument, respectively the pointer to a 390structure containing arguments, previously set by 391OSSL_CMP_CTX_set_http_cb_arg() or NULL if unset. 392 393OSSL_CMP_CTX_set_transfer_cb() sets the message transfer callback function, 394which has the type 395 396 typedef OSSL_CMP_MSG *(*OSSL_CMP_transfer_cb_t) (OSSL_CMP_CTX *ctx, 397 const OSSL_CMP_MSG *req); 398 399Returns 1 on success, 0 on error. 400 401Default is NULL, which implies the use of L<OSSL_CMP_MSG_http_perform(3)>. 402The callback should send the CMP request message it obtains via the I<req> 403parameter and on success return the response, else it must return NULL. 404The transfer callback may make use of a custom defined argument stored in 405the ctx by means of OSSL_CMP_CTX_set_transfer_cb_arg(), which may be retrieved 406again through OSSL_CMP_CTX_get_transfer_cb_arg(). 407 408OSSL_CMP_CTX_set_transfer_cb_arg() sets an argument, respectively a pointer to a 409structure containing arguments, optionally to be used by the transfer callback. 410I<arg> is not consumed, and it must therefore explicitly be freed when not 411needed any more. I<arg> may be NULL to clear the entry. 412 413OSSL_CMP_CTX_get_transfer_cb_arg() gets the argument, respectively the pointer 414to a structure containing arguments, previously set by 415OSSL_CMP_CTX_set_transfer_cb_arg() or NULL if unset. 416 417OSSL_CMP_CTX_set1_srvCert() sets the expected server cert in I<ctx> and trusts 418it directly (even if it is expired) when verifying signed response messages. 419This pins the accepted CMP server and 420results in ignoring whatever may be set using OSSL_CMP_CTX_set0_trustedStore(). 421Any previously set value is freed. 422The I<cert> argument may be NULL to clear the entry. 423If set, the subject of the certificate is also used 424as default value for the recipient of CMP requests 425and as default value for the expected sender of CMP responses. 426 427OSSL_CMP_CTX_set1_expected_sender() sets the Distinguished Name (DN) 428expected in the sender field of incoming CMP messages. 429Defaults to the subject of the pinned server certificate, if any. 430This can be used to make sure that only a particular entity is accepted as 431CMP message signer, and attackers are not able to use arbitrary certificates 432of a trusted PKI hierarchy to fraudulently pose as CMP server. 433Note that this gives slightly more freedom than OSSL_CMP_CTX_set1_srvCert(), 434which pins the server to the holder of a particular certificate, while the 435expected sender name will continue to match after updates of the server cert. 436 437OSSL_CMP_CTX_set0_trustedStore() 438sets in the CMP context I<ctx> the certificate store of type X509_STORE 439containing trusted certificates, typically of root CAs. 440This is ignored when a certificate is pinned using OSSL_CMP_CTX_set1_srvCert(). 441The store may also hold CRLs and a certificate verification callback function 442used for signature-based peer authentication. 443Any store entry already set before is freed. 444When given a NULL parameter the entry is cleared. 445 446OSSL_CMP_CTX_get0_trustedStore() 447extracts from the CMP context I<ctx> the pointer to the currently set 448certificate store containing trust anchors etc., or an empty store if unset. 449 450OSSL_CMP_CTX_set1_untrusted() sets up a list of non-trusted certificates 451of intermediate CAs that may be useful for path construction for the own CMP 452signer certificate, for the own TLS certificate (if any), when verifying peer 453CMP protection certificates, and when verifying newly enrolled certificates. 454The reference counts of those certificates handled successfully are increased. 455 456OSSL_CMP_CTX_get0_untrusted(OSSL_CMP_CTX *ctx) returns a pointer to the 457list of untrusted certs, which may be empty if unset. 458 459OSSL_CMP_CTX_set1_cert() sets the CMP signer certificate, also called protection 460certificate, related to the private key for signature-based message protection. 461Therefore the public key of this I<cert> must correspond to 462the private key set before or thereafter via OSSL_CMP_CTX_set1_pkey(). 463When using signature-based protection of CMP request messages 464this CMP signer certificate will be included first in the extraCerts field. 465It serves as fallback reference certificate, see OSSL_CMP_CTX_set1_oldCert(). 466The subject of this I<cert> will be used as the sender field of outgoing 467messages, while the subject of any cert set via OSSL_CMP_CTX_set1_oldCert() 468and any value set via OSSL_CMP_CTX_set1_subjectName() are used as fallback. 469 470The I<cert> argument may be NULL to clear the entry. 471 472OSSL_CMP_CTX_build_cert_chain() builds a certificate chain for the CMP signer 473certificate previously set in the I<ctx>. It adds the optional I<candidates>, 474a list of intermediate CA certs that may already constitute the targeted chain, 475to the untrusted certs that may already exist in the I<ctx>. 476Then the function uses this augmented set of certs for chain construction. 477If I<own_trusted> is NULL it builds the chain as far down as possible and 478ignores any verification errors. Else the CMP signer certificate must be 479verifiable where the chain reaches a trust anchor contained in I<own_trusted>. 480On success the function stores the resulting chain in I<ctx> 481for inclusion in the extraCerts field of signature-protected messages. 482Calling this function is optional; by default a chain construction 483is performed on demand that is equivalent to calling this function 484with the I<candidates> and I<own_trusted> arguments being NULL. 485 486OSSL_CMP_CTX_set1_pkey() sets the client's private key corresponding to the 487CMP signer certificate set via OSSL_CMP_CTX_set1_cert(). 488This key is used create signature-based protection (protectionAlg = MSG_SIG_ALG) 489of outgoing messages 490unless a symmetric secret has been set via OSSL_CMP_CTX_set1_secretValue(). 491The I<pkey> argument may be NULL to clear the entry. 492 493OSSL_CMP_CTX_set1_secretValue() sets in I<ctx> the byte string I<sec> of length 494I<len> to use as pre-shared secret, or clears it if the I<sec> argument is NULL. 495If present, this secret is used to create MAC-based authentication and integrity 496protection (rather than applying signature-based protection) 497of outgoing messages and to verify authenticity and integrity of incoming 498messages that have MAC-based protection (protectionAlg = C<MSG_MAC_ALG>). 499 500OSSL_CMP_CTX_set1_referenceValue() sets the given referenceValue I<ref> with 501length I<len> in the given I<ctx> or clears it if the I<ref> argument is NULL. 502According to RFC 4210 section 5.1.1, if no value for the sender field in 503CMP message headers can be determined (i.e., no CMP signer certificate 504and no subject DN is set via OSSL_CMP_CTX_set1_subjectName() 505then the sender field will contain the NULL-DN 506and the senderKID field of the CMP message header must be set. 507When signature-based protection is used the senderKID will be set to 508the subjectKeyIdentifier of the CMP signer certificate as far as present. 509If not present or when MAC-based protection is used 510the I<ref> value is taken as the fallback value for the senderKID. 511 512OSSL_CMP_CTX_set1_recipient() sets the recipient name that will be used in the 513PKIHeader of CMP request messages, i.e. the X509 name of the (CA) server. 514 515The recipient field in the header of a CMP message is mandatory. 516If not given explicitly the recipient is determined in the following order: 517the subject of the CMP server certificate set using OSSL_CMP_CTX_set1_srvCert(), 518the value set using OSSL_CMP_CTX_set1_issuer(), 519the issuer of the certificate set using OSSL_CMP_CTX_set1_oldCert(), 520the issuer of the CMP signer certificate, 521as far as any of those is present, else the NULL-DN as last resort. 522 523OSSL_CMP_CTX_push0_geninfo_ITAV() adds I<itav> to the stack in the I<ctx> to be 524added to the GeneralInfo field of the CMP PKIMessage header of a request 525message sent with this context. 526 527OSSL_CMP_CTX_reset_geninfo_ITAVs() 528clears any ITAVs that were added by OSSL_CMP_CTX_push0_geninfo_ITAV(). 529 530OSSL_CMP_CTX_set1_extraCertsOut() sets the stack of extraCerts that will be 531sent to remote. 532 533OSSL_CMP_CTX_set0_newPkey() can be used to explicitly set the given EVP_PKEY 534structure as the private or public key to be certified in the CMP context. 535The I<priv> parameter must be 0 if and only if the given key is a public key. 536 537OSSL_CMP_CTX_get0_newPkey() gives the key to use for certificate enrollment 538dependent on fields of the CMP context structure: 539the newPkey (which may be a private or public key) if present, 540else the public key in the p10CSR if present, else the client's private key. 541If the I<priv> parameter is not 0 and the selected key does not have a 542private component then NULL is returned. 543 544OSSL_CMP_CTX_set1_issuer() sets the name of the intended issuer that 545will be set in the CertTemplate, i.e., the X509 name of the CA server. 546 547OSSL_CMP_CTX_set1_subjectName() sets the subject DN that will be used in 548the CertTemplate structure when requesting a new cert. For Key Update Requests 549(KUR), it defaults to the subject DN of the reference certificate, 550see OSSL_CMP_CTX_set1_oldCert(). This default is used for Initialization 551Requests (IR) and Certification Requests (CR) only if no SANs are set. 552The I<subjectName> is also used as fallback for the sender field 553of outgoing CMP messages if no reference certificate is available. 554 555OSSL_CMP_CTX_push1_subjectAltName() adds the given X509 name to the list of 556alternate names on the certificate template request. This cannot be used if 557any Subject Alternative Name extension is set via 558OSSL_CMP_CTX_set0_reqExtensions(). 559By default, unless B<OSSL_CMP_OPT_SUBJECTALTNAME_NODEFAULT> has been set, 560the Subject Alternative Names are copied from the reference certificate, 561see OSSL_CMP_CTX_set1_oldCert(). 562If set and the subject DN is not set with OSSL_CMP_CTX_set1_subjectName() then 563the certificate template of an IR and CR will not be filled with the default 564subject DN from the reference certificate. 565If a subject DN is desired it needs to be set explicitly with 566OSSL_CMP_CTX_set1_subjectName(). 567 568OSSL_CMP_CTX_set0_reqExtensions() sets the X.509v3 extensions to be used in 569IR/CR/KUR. 570 571OSSL_CMP_CTX_reqExtensions_have_SAN() returns 1 if the context contains 572a Subject Alternative Name extension, else 0 or -1 on error. 573 574OSSL_CMP_CTX_push0_policy() adds the certificate policy info object 575to the X509_EXTENSIONS of the requested certificate template. 576 577OSSL_CMP_CTX_set1_oldCert() sets the old certificate to be updated in 578Key Update Requests (KUR) or to be revoked in Revocation Requests (RR). 579It must be given for RR, else it defaults to the CMP signer certificate. 580The I<reference certificate> determined in this way, if any, is also used for 581deriving default subject DN, public key, Subject Alternative Names, and the 582default issuer entry in the requested certificate template of IR/CR/KUR. 583The subject of the reference certificate is used as the sender field value 584in CMP message headers. 585Its issuer is used as default recipient in CMP message headers. 586 587OSSL_CMP_CTX_set1_p10CSR() sets the PKCS#10 CSR to use in P10CR messages. 588If such a CSR is provided, its subject, public key, and extension fields are 589also used as fallback values for the certificate template of IR/CR/KUR messages. 590 591OSSL_CMP_CTX_push0_genm_ITAV() adds I<itav> to the stack in the I<ctx> which 592will be the body of a General Message sent with this context. 593 594OSSL_CMP_certConf_cb() is the default certificate confirmation callback function. 595If the callback argument is not NULL it must point to a trust store. 596In this case the function checks that the newly enrolled certificate can be 597verified using this trust store and untrusted certificates from the I<ctx>, 598which have been augmented by the list of extraCerts received. 599During this verification, any certificate status checking is disabled. 600If the callback argument is NULL the function tries building an approximate 601chain as far as possible using the same untrusted certificates from the I<ctx>, 602and if this fails it takes the received extraCerts as fallback. 603The resulting cert chain can be retrieved using OSSL_CMP_CTX_get1_newChain(). 604 605OSSL_CMP_CTX_set_certConf_cb() sets the callback used for evaluating the newly 606enrolled certificate before the library sends, depending on its result, 607a positive or negative certConf message to the server. The callback has type 608 609 typedef int (*OSSL_CMP_certConf_cb_t) (OSSL_CMP_CTX *ctx, X509 *cert, 610 int fail_info, const char **txt); 611 612and should inspect the certificate it obtains via the I<cert> parameter and may 613overrule the pre-decision given in the I<fail_info> and I<*txt> parameters. 614If it accepts the certificate it must return 0, indicating success. Else it must 615return a bit field reflecting PKIFailureInfo with at least one failure bit and 616may set the I<*txt> output parameter to point to a string constant with more 617detail. The transfer callback may make use of a custom defined argument stored 618in the I<ctx> by means of OSSL_CMP_CTX_set_certConf_cb_arg(), which may be 619retrieved again through OSSL_CMP_CTX_get_certConf_cb_arg(). 620Typically, the callback will check at least that the certificate can be verified 621using a set of trusted certificates. 622It also could compare the subject DN and other fields of the newly 623enrolled certificate with the certificate template of the request. 624 625OSSL_CMP_CTX_set_certConf_cb_arg() sets an argument, respectively a pointer to a 626structure containing arguments, optionally to be used by the certConf callback. 627I<arg> is not consumed, and it must therefore explicitly be freed when not 628needed any more. I<arg> may be NULL to clear the entry. 629 630OSSL_CMP_CTX_get_certConf_cb_arg() gets the argument, respectively the pointer 631to a structure containing arguments, previously set by 632OSSL_CMP_CTX_set_certConf_cb_arg(), or NULL if unset. 633 634OSSL_CMP_CTX_get_status() returns for client contexts the PKIstatus from 635the last received CertRepMessage or Revocation Response or error message: 636=item B<OSSL_CMP_PKISTATUS_accepted> on successful receipt of a GENP message: 637 638=over 4 639 640=item B<OSSL_CMP_PKISTATUS_request> 641 642if an IR/CR/KUR/RR/GENM request message could not be produced, 643 644=item B<OSSL_CMP_PKISTATUS_trans> 645 646on a transmission error or transaction error for this type of request, and 647 648=item B<OSSL_CMP_PKISTATUS_unspecified> 649 650if no such request was attempted or OSSL_CMP_CTX_reinit() has been called. 651 652=back 653 654For server contexts it returns 655B<OSSL_CMP_PKISTATUS_trans> if a transaction is open, 656otherwise B<OSSL_CMP_PKISTATUS_unspecified>. 657 658OSSL_CMP_CTX_get0_statusString() returns the statusString from the last received 659CertRepMessage or Revocation Response or error message, or NULL if unset. 660 661OSSL_CMP_CTX_get_failInfoCode() returns the error code from the failInfo field 662of the last received CertRepMessage or Revocation Response or error message, 663or -1 if no such response was received or OSSL_CMP_CTX_reinit() has been called. 664This is a bit field and the flags for it are specified in the header file 665F<< <openssl/cmp.h> >>. 666The flags start with OSSL_CMP_CTX_FAILINFO, for example: 667OSSL_CMP_CTX_FAILINFO_badAlg. Returns -1 if the failInfoCode field is unset. 668 669OSSL_CMP_CTX_get0_newCert() returns the pointer to the newly obtained 670certificate in case it is available, else NULL. 671 672OSSL_CMP_CTX_get1_newChain() returns a pointer to a duplicate of the stack of 673X.509 certificates computed by OSSL_CMP_certConf_cb() (if this function has 674been called) on the last received certificate response message IP/CP/KUP. 675 676OSSL_CMP_CTX_get1_caPubs() returns a pointer to a duplicate of the list of 677X.509 certificates in the caPubs field of the last received certificate 678response message (of type IP, CP, or KUP), 679or an empty stack if no caPubs have been received in the current transaction. 680 681OSSL_CMP_CTX_get1_extraCertsIn() returns a pointer to a duplicate of the list 682of X.509 certificates contained in the extraCerts field of the last received 683response message (except for pollRep and PKIConf), or 684an empty stack if no extraCerts have been received in the current transaction. 685 686OSSL_CMP_CTX_set1_transactionID() sets the given transaction ID in the given 687OSSL_CMP_CTX structure. 688 689OSSL_CMP_CTX_set1_senderNonce() stores the last sent sender I<nonce> in 690the I<ctx>. This will be used to validate the recipNonce in incoming messages. 691 692=head1 NOTES 693 694CMP is defined in RFC 4210 (and CRMF in RFC 4211). 695 696=head1 RETURN VALUES 697 698OSSL_CMP_CTX_free() and OSSL_CMP_CTX_print_errors() do not return anything. 699 700OSSL_CMP_CTX_new(), 701OSSL_CMP_CTX_get_http_cb_arg(), 702OSSL_CMP_CTX_get_transfer_cb_arg(), 703OSSL_CMP_CTX_get0_trustedStore(), 704OSSL_CMP_CTX_get0_untrusted(), 705OSSL_CMP_CTX_get0_newPkey(), 706OSSL_CMP_CTX_get_certConf_cb_arg(), 707OSSL_CMP_CTX_get0_statusString(), 708OSSL_CMP_CTX_get0_newCert(), 709OSSL_CMP_CTX_get0_newChain(), 710OSSL_CMP_CTX_get1_caPubs(), and 711OSSL_CMP_CTX_get1_extraCertsIn() 712return the intended pointer value as described above or NULL on error. 713 714OSSL_CMP_CTX_get_option(), 715OSSL_CMP_CTX_reqExtensions_have_SAN(), 716OSSL_CMP_CTX_get_status(), and 717OSSL_CMP_CTX_get_failInfoCode() 718return the intended value as described above or -1 on error. 719 720OSSL_CMP_certConf_cb() returns I<fail_info> if it is not equal to 0, 721else 0 on successful validation, 722or else a bit field with the B<OSSL_CMP_PKIFAILUREINFO_incorrectData> bit set. 723 724All other functions, including OSSL_CMP_CTX_reinit() 725and OSSL_CMP_CTX_reset_geninfo_ITAVs(), 726return 1 on success, 0 on error. 727 728=head1 EXAMPLES 729 730The following code omits error handling. 731 732Set up a CMP client context for sending requests and verifying responses: 733 734 cmp_ctx = OSSL_CMP_CTX_new(); 735 OSSL_CMP_CTX_set1_server(cmp_ctx, name_or_address); 736 OSSL_CMP_CTX_set1_serverPort(cmp_ctx, port_string); 737 OSSL_CMP_CTX_set1_serverPath(cmp_ctx, path_or_alias); 738 OSSL_CMP_CTX_set0_trustedStore(cmp_ctx, ts); 739 740Set up symmetric credentials for MAC-based message protection such as PBM: 741 742 OSSL_CMP_CTX_set1_referenceValue(cmp_ctx, ref, ref_len); 743 OSSL_CMP_CTX_set1_secretValue(cmp_ctx, sec, sec_len); 744 745Set up the details for certificate requests: 746 747 OSSL_CMP_CTX_set1_subjectName(cmp_ctx, name); 748 OSSL_CMP_CTX_set0_newPkey(cmp_ctx, 1, initialKey); 749 750Perform an Initialization Request transaction: 751 752 initialCert = OSSL_CMP_exec_IR_ses(cmp_ctx); 753 754Reset the transaction state of the CMP context and the credentials: 755 756 OSSL_CMP_CTX_reinit(cmp_ctx); 757 OSSL_CMP_CTX_set1_referenceValue(cmp_ctx, NULL, 0); 758 OSSL_CMP_CTX_set1_secretValue(cmp_ctx, NULL, 0); 759 760Perform a Certification Request transaction, making use of the new credentials: 761 762 OSSL_CMP_CTX_set1_cert(cmp_ctx, initialCert); 763 OSSL_CMP_CTX_set1_pkey(cmp_ctx, initialKey); 764 OSSL_CMP_CTX_set0_newPkey(cmp_ctx, 1, curentKey); 765 currentCert = OSSL_CMP_exec_CR_ses(cmp_ctx); 766 767Perform a Key Update Request, signed using the cert (and key) to be updated: 768 769 OSSL_CMP_CTX_reinit(cmp_ctx); 770 OSSL_CMP_CTX_set1_cert(cmp_ctx, currentCert); 771 OSSL_CMP_CTX_set1_pkey(cmp_ctx, currentKey); 772 OSSL_CMP_CTX_set0_newPkey(cmp_ctx, 1, updatedKey); 773 currentCert = OSSL_CMP_exec_KUR_ses(cmp_ctx); 774 currentKey = updatedKey; 775 776Perform a General Message transaction including, as an example, 777the id-it-signKeyPairTypes OID and prints info on the General Response contents: 778 779 OSSL_CMP_CTX_reinit(cmp_ctx); 780 781 ASN1_OBJECT *type = OBJ_txt2obj("1.3.6.1.5.5.7.4.2", 1); 782 OSSL_CMP_ITAV *itav = OSSL_CMP_ITAV_create(type, NULL); 783 OSSL_CMP_CTX_push0_genm_ITAV(cmp_ctx, itav); 784 785 STACK_OF(OSSL_CMP_ITAV) *itavs; 786 itavs = OSSL_CMP_exec_GENM_ses(cmp_ctx); 787 print_itavs(itavs); 788 sk_OSSL_CMP_ITAV_pop_free(itavs, OSSL_CMP_ITAV_free); 789 790=head1 SEE ALSO 791 792L<OSSL_CMP_exec_IR_ses(3)>, L<OSSL_CMP_exec_CR_ses(3)>, 793L<OSSL_CMP_exec_KUR_ses(3)>, L<OSSL_CMP_exec_GENM_ses(3)>, 794L<OSSL_CMP_exec_certreq(3)>, L<OSSL_CMP_MSG_http_perform(3)>, 795L<ERR_print_errors_cb(3)> 796 797=head1 HISTORY 798 799The OpenSSL CMP support was added in OpenSSL 3.0. 800 801OSSL_CMP_CTX_reset_geninfo_ITAVs() was added in OpenSSL 3.0.8. 802 803=head1 COPYRIGHT 804 805Copyright 2007-2024 The OpenSSL Project Authors. All Rights Reserved. 806 807Licensed under the Apache License 2.0 (the "License"). You may not use 808this file except in compliance with the License. You can obtain a copy 809in the file LICENSE in the source distribution or at 810L<https://www.openssl.org/source/license.html>. 811 812=cut 813