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. 358Otherwise the format is 359C<[http[s]://][userinfo@]host[:port][/path][?query][#fragment]>, 360where any given userinfo, path, query, and fragment is ignored. 361If the host string is an IPv6 address, it must be enclosed in C<[> and C<]>. 362The default port number is 80, or 443 in case C<https:> is given. 363 364OSSL_CMP_CTX_set1_no_proxy() sets the list of server hostnames not to use 365an HTTP proxy for. The names may be separated by commas and/or whitespace. 366Defaults to the environment variable C<no_proxy> if set, else C<NO_PROXY>. 367 368OSSL_CMP_CTX_set_http_cb() sets the optional BIO connect/disconnect callback 369function, which has the prototype 370 371 typedef BIO *(*HTTP_bio_cb_t) (BIO *bio, void *ctx, int connect, int detail); 372 373The callback may modify the I<bio> provided by L<OSSL_CMP_MSG_http_perform(3)>, 374whereby it may make use of a custom defined argument I<ctx> 375stored in the OSSL_CMP_CTX by means of OSSL_CMP_CTX_set_http_cb_arg(). 376During connection establishment, just after calling BIO_do_connect_retry(), 377the function is invoked with the I<connect> argument being 1 and the I<detail> 378argument being 1 if HTTPS is requested, i.e., SSL/TLS should be enabled. On 379disconnect I<connect> is 0 and I<detail> is 1 in case no error occurred, else 0. 380For instance, on connect the function may prepend a TLS BIO to implement HTTPS; 381after disconnect it may do some diagnostic output and/or specific cleanup. 382The function should return NULL to indicate failure. 383After disconnect the modified BIO will be deallocated using BIO_free_all(). 384 385OSSL_CMP_CTX_set_http_cb_arg() sets an argument, respectively a pointer to 386a structure containing arguments, 387optionally to be used by the http connect/disconnect callback function. 388I<arg> is not consumed, and it must therefore explicitly be freed when not 389needed any more. I<arg> may be NULL to clear the entry. 390 391OSSL_CMP_CTX_get_http_cb_arg() gets the argument, respectively the pointer to a 392structure containing arguments, previously set by 393OSSL_CMP_CTX_set_http_cb_arg() or NULL if unset. 394 395OSSL_CMP_CTX_set_transfer_cb() sets the message transfer callback function, 396which has the type 397 398 typedef OSSL_CMP_MSG *(*OSSL_CMP_transfer_cb_t) (OSSL_CMP_CTX *ctx, 399 const OSSL_CMP_MSG *req); 400 401Returns 1 on success, 0 on error. 402 403Default is NULL, which implies the use of L<OSSL_CMP_MSG_http_perform(3)>. 404The callback should send the CMP request message it obtains via the I<req> 405parameter and on success return the response, else it must return NULL. 406The transfer callback may make use of a custom defined argument stored in 407the ctx by means of OSSL_CMP_CTX_set_transfer_cb_arg(), which may be retrieved 408again through OSSL_CMP_CTX_get_transfer_cb_arg(). 409 410OSSL_CMP_CTX_set_transfer_cb_arg() sets an argument, respectively a pointer to a 411structure containing arguments, optionally to be used by the transfer callback. 412I<arg> is not consumed, and it must therefore explicitly be freed when not 413needed any more. I<arg> may be NULL to clear the entry. 414 415OSSL_CMP_CTX_get_transfer_cb_arg() gets the argument, respectively the pointer 416to a structure containing arguments, previously set by 417OSSL_CMP_CTX_set_transfer_cb_arg() or NULL if unset. 418 419OSSL_CMP_CTX_set1_srvCert() sets the expected server cert in I<ctx> and trusts 420it directly (even if it is expired) when verifying signed response messages. 421This pins the accepted CMP server and 422results in ignoring whatever may be set using OSSL_CMP_CTX_set0_trustedStore(). 423Any previously set value is freed. 424The I<cert> argument may be NULL to clear the entry. 425If set, the subject of the certificate is also used 426as default value for the recipient of CMP requests 427and as default value for the expected sender of CMP responses. 428 429OSSL_CMP_CTX_set1_expected_sender() sets the Distinguished Name (DN) 430expected in the sender field of incoming CMP messages. 431Defaults to the subject of the pinned server certificate, if any. 432This can be used to make sure that only a particular entity is accepted as 433CMP message signer, and attackers are not able to use arbitrary certificates 434of a trusted PKI hierarchy to fraudulently pose as CMP server. 435Note that this gives slightly more freedom than OSSL_CMP_CTX_set1_srvCert(), 436which pins the server to the holder of a particular certificate, while the 437expected sender name will continue to match after updates of the server cert. 438 439OSSL_CMP_CTX_set0_trustedStore() 440sets in the CMP context I<ctx> the certificate store of type X509_STORE 441containing trusted certificates, typically of root CAs. 442This is ignored when a certificate is pinned using OSSL_CMP_CTX_set1_srvCert(). 443The store may also hold CRLs and a certificate verification callback function 444used for signature-based peer authentication. 445Any store entry already set before is freed. 446When given a NULL parameter the entry is cleared. 447 448OSSL_CMP_CTX_get0_trustedStore() 449extracts from the CMP context I<ctx> the pointer to the currently set 450certificate store containing trust anchors etc., or an empty store if unset. 451 452OSSL_CMP_CTX_set1_untrusted() sets up a list of non-trusted certificates 453of intermediate CAs that may be useful for path construction for the own CMP 454signer certificate, for the own TLS certificate (if any), when verifying peer 455CMP protection certificates, and when verifying newly enrolled certificates. 456The reference counts of those certificates handled successfully are increased. 457 458OSSL_CMP_CTX_get0_untrusted(OSSL_CMP_CTX *ctx) returns a pointer to the 459list of untrusted certs, which may be empty if unset. 460 461OSSL_CMP_CTX_set1_cert() sets the CMP signer certificate, also called protection 462certificate, related to the private key for signature-based message protection. 463Therefore the public key of this I<cert> must correspond to 464the private key set before or thereafter via OSSL_CMP_CTX_set1_pkey(). 465When using signature-based protection of CMP request messages 466this CMP signer certificate will be included first in the extraCerts field. 467It serves as fallback reference certificate, see OSSL_CMP_CTX_set1_oldCert(). 468The subject of this I<cert> will be used as the sender field of outgoing 469messages, while the subject of any cert set via OSSL_CMP_CTX_set1_oldCert() 470and any value set via OSSL_CMP_CTX_set1_subjectName() are used as fallback. 471 472The I<cert> argument may be NULL to clear the entry. 473 474OSSL_CMP_CTX_build_cert_chain() builds a certificate chain for the CMP signer 475certificate previously set in the I<ctx>. It adds the optional I<candidates>, 476a list of intermediate CA certs that may already constitute the targeted chain, 477to the untrusted certs that may already exist in the I<ctx>. 478Then the function uses this augmented set of certs for chain construction. 479If I<own_trusted> is NULL it builds the chain as far down as possible and 480ignores any verification errors. Else the CMP signer certificate must be 481verifiable where the chain reaches a trust anchor contained in I<own_trusted>. 482On success the function stores the resulting chain in I<ctx> 483for inclusion in the extraCerts field of signature-protected messages. 484Calling this function is optional; by default a chain construction 485is performed on demand that is equivalent to calling this function 486with the I<candidates> and I<own_trusted> arguments being NULL. 487 488OSSL_CMP_CTX_set1_pkey() sets the client's private key corresponding to the 489CMP signer certificate set via OSSL_CMP_CTX_set1_cert(). 490This key is used create signature-based protection (protectionAlg = MSG_SIG_ALG) 491of outgoing messages 492unless a symmetric secret has been set via OSSL_CMP_CTX_set1_secretValue(). 493The I<pkey> argument may be NULL to clear the entry. 494 495OSSL_CMP_CTX_set1_secretValue() sets in I<ctx> the byte string I<sec> of length 496I<len> to use as pre-shared secret, or clears it if the I<sec> argument is NULL. 497If present, this secret is used to create MAC-based authentication and integrity 498protection (rather than applying signature-based protection) 499of outgoing messages and to verify authenticity and integrity of incoming 500messages that have MAC-based protection (protectionAlg = C<MSG_MAC_ALG>). 501 502OSSL_CMP_CTX_set1_referenceValue() sets the given referenceValue I<ref> with 503length I<len> in the given I<ctx> or clears it if the I<ref> argument is NULL. 504According to RFC 4210 section 5.1.1, if no value for the sender field in 505CMP message headers can be determined (i.e., no CMP signer certificate 506and no subject DN is set via OSSL_CMP_CTX_set1_subjectName() 507then the sender field will contain the NULL-DN 508and the senderKID field of the CMP message header must be set. 509When signature-based protection is used the senderKID will be set to 510the subjectKeyIdentifier of the CMP signer certificate as far as present. 511If not present or when MAC-based protection is used 512the I<ref> value is taken as the fallback value for the senderKID. 513 514OSSL_CMP_CTX_set1_recipient() sets the recipient name that will be used in the 515PKIHeader of CMP request messages, i.e. the X509 name of the (CA) server. 516 517The recipient field in the header of a CMP message is mandatory. 518If not given explicitly the recipient is determined in the following order: 519the subject of the CMP server certificate set using OSSL_CMP_CTX_set1_srvCert(), 520the value set using OSSL_CMP_CTX_set1_issuer(), 521the issuer of the certificate set using OSSL_CMP_CTX_set1_oldCert(), 522the issuer of the CMP signer certificate, 523as far as any of those is present, else the NULL-DN as last resort. 524 525OSSL_CMP_CTX_push0_geninfo_ITAV() adds I<itav> to the stack in the I<ctx> to be 526added to the GeneralInfo field of the CMP PKIMessage header of a request 527message sent with this context. 528 529OSSL_CMP_CTX_reset_geninfo_ITAVs() 530clears any ITAVs that were added by OSSL_CMP_CTX_push0_geninfo_ITAV(). 531 532OSSL_CMP_CTX_set1_extraCertsOut() sets the stack of extraCerts that will be 533sent to remote. 534 535OSSL_CMP_CTX_set0_newPkey() can be used to explicitly set the given EVP_PKEY 536structure as the private or public key to be certified in the CMP context. 537The I<priv> parameter must be 0 if and only if the given key is a public key. 538 539OSSL_CMP_CTX_get0_newPkey() gives the key to use for certificate enrollment 540dependent on fields of the CMP context structure: 541the newPkey (which may be a private or public key) if present, 542else the public key in the p10CSR if present, else the client's private key. 543If the I<priv> parameter is not 0 and the selected key does not have a 544private component then NULL is returned. 545 546OSSL_CMP_CTX_set1_issuer() sets the name of the intended issuer that 547will be set in the CertTemplate, i.e., the X509 name of the CA server. 548 549OSSL_CMP_CTX_set1_subjectName() sets the subject DN that will be used in 550the CertTemplate structure when requesting a new cert. For Key Update Requests 551(KUR), it defaults to the subject DN of the reference certificate, 552see OSSL_CMP_CTX_set1_oldCert(). This default is used for Initialization 553Requests (IR) and Certification Requests (CR) only if no SANs are set. 554The I<subjectName> is also used as fallback for the sender field 555of outgoing CMP messages if no reference certificate is available. 556 557OSSL_CMP_CTX_push1_subjectAltName() adds the given X509 name to the list of 558alternate names on the certificate template request. This cannot be used if 559any Subject Alternative Name extension is set via 560OSSL_CMP_CTX_set0_reqExtensions(). 561By default, unless B<OSSL_CMP_OPT_SUBJECTALTNAME_NODEFAULT> has been set, 562the Subject Alternative Names are copied from the reference certificate, 563see OSSL_CMP_CTX_set1_oldCert(). 564If set and the subject DN is not set with OSSL_CMP_CTX_set1_subjectName() then 565the certificate template of an IR and CR will not be filled with the default 566subject DN from the reference certificate. 567If a subject DN is desired it needs to be set explicitly with 568OSSL_CMP_CTX_set1_subjectName(). 569 570OSSL_CMP_CTX_set0_reqExtensions() sets the X.509v3 extensions to be used in 571IR/CR/KUR. 572 573OSSL_CMP_CTX_reqExtensions_have_SAN() returns 1 if the context contains 574a Subject Alternative Name extension, else 0 or -1 on error. 575 576OSSL_CMP_CTX_push0_policy() adds the certificate policy info object 577to the X509_EXTENSIONS of the requested certificate template. 578 579OSSL_CMP_CTX_set1_oldCert() sets the old certificate to be updated in 580Key Update Requests (KUR) or to be revoked in Revocation Requests (RR). 581It must be given for RR, else it defaults to the CMP signer certificate. 582The I<reference certificate> determined in this way, if any, is also used for 583deriving default subject DN, public key, Subject Alternative Names, and the 584default issuer entry in the requested certificate template of IR/CR/KUR. 585The subject of the reference certificate is used as the sender field value 586in CMP message headers. 587Its issuer is used as default recipient in CMP message headers. 588 589OSSL_CMP_CTX_set1_p10CSR() sets the PKCS#10 CSR to use in P10CR messages. 590If such a CSR is provided, its subject, public key, and extension fields are 591also used as fallback values for the certificate template of IR/CR/KUR messages. 592 593OSSL_CMP_CTX_push0_genm_ITAV() adds I<itav> to the stack in the I<ctx> which 594will be the body of a General Message sent with this context. 595 596OSSL_CMP_certConf_cb() is the default certificate confirmation callback function. 597If the callback argument is not NULL it must point to a trust store. 598In this case the function checks that the newly enrolled certificate can be 599verified using this trust store and untrusted certificates from the I<ctx>, 600which have been augmented by the list of extraCerts received. 601During this verification, any certificate status checking is disabled. 602If the callback argument is NULL the function tries building an approximate 603chain as far as possible using the same untrusted certificates from the I<ctx>, 604and if this fails it takes the received extraCerts as fallback. 605The resulting cert chain can be retrieved using OSSL_CMP_CTX_get1_newChain(). 606 607OSSL_CMP_CTX_set_certConf_cb() sets the callback used for evaluating the newly 608enrolled certificate before the library sends, depending on its result, 609a positive or negative certConf message to the server. The callback has type 610 611 typedef int (*OSSL_CMP_certConf_cb_t) (OSSL_CMP_CTX *ctx, X509 *cert, 612 int fail_info, const char **txt); 613 614and should inspect the certificate it obtains via the I<cert> parameter and may 615overrule the pre-decision given in the I<fail_info> and I<*txt> parameters. 616If it accepts the certificate it must return 0, indicating success. Else it must 617return a bit field reflecting PKIFailureInfo with at least one failure bit and 618may set the I<*txt> output parameter to point to a string constant with more 619detail. The transfer callback may make use of a custom defined argument stored 620in the I<ctx> by means of OSSL_CMP_CTX_set_certConf_cb_arg(), which may be 621retrieved again through OSSL_CMP_CTX_get_certConf_cb_arg(). 622Typically, the callback will check at least that the certificate can be verified 623using a set of trusted certificates. 624It also could compare the subject DN and other fields of the newly 625enrolled certificate with the certificate template of the request. 626 627OSSL_CMP_CTX_set_certConf_cb_arg() sets an argument, respectively a pointer to a 628structure containing arguments, optionally to be used by the certConf callback. 629I<arg> is not consumed, and it must therefore explicitly be freed when not 630needed any more. I<arg> may be NULL to clear the entry. 631 632OSSL_CMP_CTX_get_certConf_cb_arg() gets the argument, respectively the pointer 633to a structure containing arguments, previously set by 634OSSL_CMP_CTX_set_certConf_cb_arg(), or NULL if unset. 635 636OSSL_CMP_CTX_get_status() returns for client contexts the PKIstatus from 637the last received CertRepMessage or Revocation Response or error message: 638=item B<OSSL_CMP_PKISTATUS_accepted> on successful receipt of a GENP message: 639 640=over 4 641 642=item B<OSSL_CMP_PKISTATUS_request> 643 644if an IR/CR/KUR/RR/GENM request message could not be produced, 645 646=item B<OSSL_CMP_PKISTATUS_trans> 647 648on a transmission error or transaction error for this type of request, and 649 650=item B<OSSL_CMP_PKISTATUS_unspecified> 651 652if no such request was attempted or OSSL_CMP_CTX_reinit() has been called. 653 654=back 655 656For server contexts it returns 657B<OSSL_CMP_PKISTATUS_trans> if a transaction is open, 658otherwise B<OSSL_CMP_PKISTATUS_unspecified>. 659 660OSSL_CMP_CTX_get0_statusString() returns the statusString from the last received 661CertRepMessage or Revocation Response or error message, or NULL if unset. 662 663OSSL_CMP_CTX_get_failInfoCode() returns the error code from the failInfo field 664of the last received CertRepMessage or Revocation Response or error message, 665or -1 if no such response was received or OSSL_CMP_CTX_reinit() has been called. 666This is a bit field and the flags for it are specified in the header file 667F<< <openssl/cmp.h> >>. 668The flags start with OSSL_CMP_CTX_FAILINFO, for example: 669OSSL_CMP_CTX_FAILINFO_badAlg. Returns -1 if the failInfoCode field is unset. 670 671OSSL_CMP_CTX_get0_newCert() returns the pointer to the newly obtained 672certificate in case it is available, else NULL. 673 674OSSL_CMP_CTX_get1_newChain() returns a pointer to a duplicate of the stack of 675X.509 certificates computed by OSSL_CMP_certConf_cb() (if this function has 676been called) on the last received certificate response message IP/CP/KUP. 677 678OSSL_CMP_CTX_get1_caPubs() returns a pointer to a duplicate of the list of 679X.509 certificates in the caPubs field of the last received certificate 680response message (of type IP, CP, or KUP), 681or an empty stack if no caPubs have been received in the current transaction. 682 683OSSL_CMP_CTX_get1_extraCertsIn() returns a pointer to a duplicate of the list 684of X.509 certificates contained in the extraCerts field of the last received 685response message (except for pollRep and PKIConf), or 686an empty stack if no extraCerts have been received in the current transaction. 687 688OSSL_CMP_CTX_set1_transactionID() sets the given transaction ID in the given 689OSSL_CMP_CTX structure. 690 691OSSL_CMP_CTX_set1_senderNonce() stores the last sent sender I<nonce> in 692the I<ctx>. This will be used to validate the recipNonce in incoming messages. 693 694=head1 NOTES 695 696CMP is defined in RFC 4210 (and CRMF in RFC 4211). 697 698=head1 RETURN VALUES 699 700OSSL_CMP_CTX_free() and OSSL_CMP_CTX_print_errors() do not return anything. 701 702OSSL_CMP_CTX_new(), 703OSSL_CMP_CTX_get_http_cb_arg(), 704OSSL_CMP_CTX_get_transfer_cb_arg(), 705OSSL_CMP_CTX_get0_trustedStore(), 706OSSL_CMP_CTX_get0_untrusted(), 707OSSL_CMP_CTX_get0_newPkey(), 708OSSL_CMP_CTX_get_certConf_cb_arg(), 709OSSL_CMP_CTX_get0_statusString(), 710OSSL_CMP_CTX_get0_newCert(), 711OSSL_CMP_CTX_get0_newChain(), 712OSSL_CMP_CTX_get1_caPubs(), and 713OSSL_CMP_CTX_get1_extraCertsIn() 714return the intended pointer value as described above or NULL on error. 715 716OSSL_CMP_CTX_get_option(), 717OSSL_CMP_CTX_reqExtensions_have_SAN(), 718OSSL_CMP_CTX_get_status(), and 719OSSL_CMP_CTX_get_failInfoCode() 720return the intended value as described above or -1 on error. 721 722OSSL_CMP_certConf_cb() returns I<fail_info> if it is not equal to 0, 723else 0 on successful validation, 724or else a bit field with the B<OSSL_CMP_PKIFAILUREINFO_incorrectData> bit set. 725 726All other functions, including OSSL_CMP_CTX_reinit() 727and OSSL_CMP_CTX_reset_geninfo_ITAVs(), 728return 1 on success, 0 on error. 729 730=head1 EXAMPLES 731 732The following code omits error handling. 733 734Set up a CMP client context for sending requests and verifying responses: 735 736 cmp_ctx = OSSL_CMP_CTX_new(); 737 OSSL_CMP_CTX_set1_server(cmp_ctx, name_or_address); 738 OSSL_CMP_CTX_set1_serverPort(cmp_ctx, port_string); 739 OSSL_CMP_CTX_set1_serverPath(cmp_ctx, path_or_alias); 740 OSSL_CMP_CTX_set0_trustedStore(cmp_ctx, ts); 741 742Set up symmetric credentials for MAC-based message protection such as PBM: 743 744 OSSL_CMP_CTX_set1_referenceValue(cmp_ctx, ref, ref_len); 745 OSSL_CMP_CTX_set1_secretValue(cmp_ctx, sec, sec_len); 746 747Set up the details for certificate requests: 748 749 OSSL_CMP_CTX_set1_subjectName(cmp_ctx, name); 750 OSSL_CMP_CTX_set0_newPkey(cmp_ctx, 1, initialKey); 751 752Perform an Initialization Request transaction: 753 754 initialCert = OSSL_CMP_exec_IR_ses(cmp_ctx); 755 756Reset the transaction state of the CMP context and the credentials: 757 758 OSSL_CMP_CTX_reinit(cmp_ctx); 759 OSSL_CMP_CTX_set1_referenceValue(cmp_ctx, NULL, 0); 760 OSSL_CMP_CTX_set1_secretValue(cmp_ctx, NULL, 0); 761 762Perform a Certification Request transaction, making use of the new credentials: 763 764 OSSL_CMP_CTX_set1_cert(cmp_ctx, initialCert); 765 OSSL_CMP_CTX_set1_pkey(cmp_ctx, initialKey); 766 OSSL_CMP_CTX_set0_newPkey(cmp_ctx, 1, curentKey); 767 currentCert = OSSL_CMP_exec_CR_ses(cmp_ctx); 768 769Perform a Key Update Request, signed using the cert (and key) to be updated: 770 771 OSSL_CMP_CTX_reinit(cmp_ctx); 772 OSSL_CMP_CTX_set1_cert(cmp_ctx, currentCert); 773 OSSL_CMP_CTX_set1_pkey(cmp_ctx, currentKey); 774 OSSL_CMP_CTX_set0_newPkey(cmp_ctx, 1, updatedKey); 775 currentCert = OSSL_CMP_exec_KUR_ses(cmp_ctx); 776 currentKey = updatedKey; 777 778Perform a General Message transaction including, as an example, 779the id-it-signKeyPairTypes OID and prints info on the General Response contents: 780 781 OSSL_CMP_CTX_reinit(cmp_ctx); 782 783 ASN1_OBJECT *type = OBJ_txt2obj("1.3.6.1.5.5.7.4.2", 1); 784 OSSL_CMP_ITAV *itav = OSSL_CMP_ITAV_create(type, NULL); 785 OSSL_CMP_CTX_push0_genm_ITAV(cmp_ctx, itav); 786 787 STACK_OF(OSSL_CMP_ITAV) *itavs; 788 itavs = OSSL_CMP_exec_GENM_ses(cmp_ctx); 789 print_itavs(itavs); 790 sk_OSSL_CMP_ITAV_pop_free(itavs, OSSL_CMP_ITAV_free); 791 792=head1 SEE ALSO 793 794L<OSSL_CMP_exec_IR_ses(3)>, L<OSSL_CMP_exec_CR_ses(3)>, 795L<OSSL_CMP_exec_KUR_ses(3)>, L<OSSL_CMP_exec_GENM_ses(3)>, 796L<OSSL_CMP_exec_certreq(3)>, L<OSSL_CMP_MSG_http_perform(3)>, 797L<ERR_print_errors_cb(3)> 798 799=head1 HISTORY 800 801The OpenSSL CMP support was added in OpenSSL 3.0. 802 803OSSL_CMP_CTX_reset_geninfo_ITAVs() was added in OpenSSL 3.0.8. 804 805=head1 COPYRIGHT 806 807Copyright 2007-2024 The OpenSSL Project Authors. All Rights Reserved. 808 809Licensed under the Apache License 2.0 (the "License"). You may not use 810this file except in compliance with the License. You can obtain a copy 811in the file LICENSE in the source distribution or at 812L<https://www.openssl.org/source/license.html>. 813 814=cut 815