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_trusted, 28OSSL_CMP_CTX_set0_trustedStore, 29OSSL_CMP_CTX_get0_trusted, 30OSSL_CMP_CTX_get0_trustedStore, 31OSSL_CMP_CTX_set1_untrusted, 32OSSL_CMP_CTX_get0_untrusted, 33OSSL_CMP_CTX_set1_cert, 34OSSL_CMP_CTX_build_cert_chain, 35OSSL_CMP_CTX_set1_pkey, 36OSSL_CMP_CTX_set1_referenceValue, 37OSSL_CMP_CTX_set1_secretValue, 38OSSL_CMP_CTX_set1_recipient, 39OSSL_CMP_CTX_push0_geninfo_ITAV, 40OSSL_CMP_CTX_set1_extraCertsOut, 41OSSL_CMP_CTX_set0_newPkey, 42OSSL_CMP_CTX_get0_newPkey, 43OSSL_CMP_CTX_set1_issuer, 44OSSL_CMP_CTX_set1_subjectName, 45OSSL_CMP_CTX_push1_subjectAltName, 46OSSL_CMP_CTX_set0_reqExtensions, 47OSSL_CMP_CTX_reqExtensions_have_SAN, 48OSSL_CMP_CTX_push0_policy, 49OSSL_CMP_CTX_set1_oldCert, 50OSSL_CMP_CTX_set1_p10CSR, 51OSSL_CMP_CTX_push0_genm_ITAV, 52OSSL_CMP_certConf_cb_t, 53OSSL_CMP_certConf_cb, 54OSSL_CMP_CTX_set_certConf_cb, 55OSSL_CMP_CTX_set_certConf_cb_arg, 56OSSL_CMP_CTX_get_certConf_cb_arg, 57OSSL_CMP_CTX_get_status, 58OSSL_CMP_CTX_get0_statusString, 59OSSL_CMP_CTX_get_failInfoCode, 60OSSL_CMP_CTX_get0_validatedSrvCert, 61OSSL_CMP_CTX_get0_newCert, 62OSSL_CMP_CTX_get1_newChain, 63OSSL_CMP_CTX_get1_caPubs, 64OSSL_CMP_CTX_get1_extraCertsIn, 65OSSL_CMP_CTX_set1_transactionID, 66OSSL_CMP_CTX_set1_senderNonce 67- functions for managing the CMP client context data structure 68 69=head1 SYNOPSIS 70 71 #include <openssl/cmp.h> 72 73 OSSL_CMP_CTX *OSSL_CMP_CTX_new(OSSL_LIB_CTX *libctx, const char *propq); 74 void OSSL_CMP_CTX_free(OSSL_CMP_CTX *ctx); 75 int OSSL_CMP_CTX_reinit(OSSL_CMP_CTX *ctx); 76 int OSSL_CMP_CTX_set_option(OSSL_CMP_CTX *ctx, int opt, int val); 77 int OSSL_CMP_CTX_get_option(const OSSL_CMP_CTX *ctx, int opt); 78 79 /* logging and error reporting: */ 80 int OSSL_CMP_CTX_set_log_cb(OSSL_CMP_CTX *ctx, OSSL_CMP_log_cb_t cb); 81 #define OSSL_CMP_CTX_set_log_verbosity(ctx, level) 82 void OSSL_CMP_CTX_print_errors(const OSSL_CMP_CTX *ctx); 83 84 /* message transfer: */ 85 int OSSL_CMP_CTX_set1_serverPath(OSSL_CMP_CTX *ctx, const char *path); 86 int OSSL_CMP_CTX_set1_server(OSSL_CMP_CTX *ctx, const char *address); 87 int OSSL_CMP_CTX_set_serverPort(OSSL_CMP_CTX *ctx, int port); 88 int OSSL_CMP_CTX_set1_proxy(OSSL_CMP_CTX *ctx, const char *name); 89 int OSSL_CMP_CTX_set1_no_proxy(OSSL_CMP_CTX *ctx, const char *names); 90 int OSSL_CMP_CTX_set_http_cb(OSSL_CMP_CTX *ctx, HTTP_bio_cb_t cb); 91 int OSSL_CMP_CTX_set_http_cb_arg(OSSL_CMP_CTX *ctx, void *arg); 92 void *OSSL_CMP_CTX_get_http_cb_arg(const OSSL_CMP_CTX *ctx); 93 typedef OSSL_CMP_MSG *(*OSSL_CMP_transfer_cb_t)(OSSL_CMP_CTX *ctx, 94 const OSSL_CMP_MSG *req); 95 int OSSL_CMP_CTX_set_transfer_cb(OSSL_CMP_CTX *ctx, 96 OSSL_CMP_transfer_cb_t cb); 97 int OSSL_CMP_CTX_set_transfer_cb_arg(OSSL_CMP_CTX *ctx, void *arg); 98 void *OSSL_CMP_CTX_get_transfer_cb_arg(const OSSL_CMP_CTX *ctx); 99 100 /* server authentication: */ 101 int OSSL_CMP_CTX_set1_srvCert(OSSL_CMP_CTX *ctx, X509 *cert); 102 int OSSL_CMP_CTX_set1_expected_sender(OSSL_CMP_CTX *ctx, 103 const X509_NAME *name); 104 #define OSSL_CMP_CTX_set0_trusted OSSL_CMP_CTX_set0_trustedStore 105 int OSSL_CMP_CTX_set0_trustedStore(OSSL_CMP_CTX *ctx, X509_STORE *store); 106 #define OSSL_CMP_CTX_get0_trusted OSSL_CMP_CTX_get0_trustedStore 107 X509_STORE *OSSL_CMP_CTX_get0_trustedStore(const OSSL_CMP_CTX *ctx); 108 int OSSL_CMP_CTX_set1_untrusted(OSSL_CMP_CTX *ctx, STACK_OF(X509) *certs); 109 STACK_OF(X509) *OSSL_CMP_CTX_get0_untrusted(const OSSL_CMP_CTX *ctx); 110 111 /* client authentication: */ 112 int OSSL_CMP_CTX_set1_cert(OSSL_CMP_CTX *ctx, X509 *cert); 113 int OSSL_CMP_CTX_build_cert_chain(OSSL_CMP_CTX *ctx, X509_STORE *own_trusted, 114 STACK_OF(X509) *candidates); 115 int OSSL_CMP_CTX_set1_pkey(OSSL_CMP_CTX *ctx, EVP_PKEY *pkey); 116 int OSSL_CMP_CTX_set1_referenceValue(OSSL_CMP_CTX *ctx, 117 const unsigned char *ref, int len); 118 int OSSL_CMP_CTX_set1_secretValue(OSSL_CMP_CTX *ctx, const unsigned char *sec, 119 const int len); 120 121 /* CMP message header and extra certificates: */ 122 int OSSL_CMP_CTX_set1_recipient(OSSL_CMP_CTX *ctx, const X509_NAME *name); 123 int OSSL_CMP_CTX_push0_geninfo_ITAV(OSSL_CMP_CTX *ctx, OSSL_CMP_ITAV *itav); 124 int OSSL_CMP_CTX_set1_extraCertsOut(OSSL_CMP_CTX *ctx, 125 STACK_OF(X509) *extraCertsOut); 126 127 /* certificate template: */ 128 int OSSL_CMP_CTX_set0_newPkey(OSSL_CMP_CTX *ctx, int priv, EVP_PKEY *pkey); 129 EVP_PKEY *OSSL_CMP_CTX_get0_newPkey(const OSSL_CMP_CTX *ctx, int priv); 130 int OSSL_CMP_CTX_set1_issuer(OSSL_CMP_CTX *ctx, const X509_NAME *name); 131 int OSSL_CMP_CTX_set1_subjectName(OSSL_CMP_CTX *ctx, const X509_NAME *name); 132 int OSSL_CMP_CTX_push1_subjectAltName(OSSL_CMP_CTX *ctx, 133 const GENERAL_NAME *name); 134 int OSSL_CMP_CTX_set0_reqExtensions(OSSL_CMP_CTX *ctx, X509_EXTENSIONS *exts); 135 int OSSL_CMP_CTX_reqExtensions_have_SAN(OSSL_CMP_CTX *ctx); 136 int OSSL_CMP_CTX_push0_policy(OSSL_CMP_CTX *ctx, POLICYINFO *pinfo); 137 int OSSL_CMP_CTX_set1_oldCert(OSSL_CMP_CTX *ctx, X509 *cert); 138 int OSSL_CMP_CTX_set1_p10CSR(OSSL_CMP_CTX *ctx, const X509_REQ *csr); 139 140 /* misc body contents: */ 141 int OSSL_CMP_CTX_push0_genm_ITAV(OSSL_CMP_CTX *ctx, OSSL_CMP_ITAV *itav); 142 143 /* certificate confirmation: */ 144 typedef int (*OSSL_CMP_certConf_cb_t)(OSSL_CMP_CTX *ctx, X509 *cert, 145 int fail_info, const char **txt); 146 int OSSL_CMP_certConf_cb(OSSL_CMP_CTX *ctx, X509 *cert, int fail_info, 147 const char **text); 148 int OSSL_CMP_CTX_set_certConf_cb(OSSL_CMP_CTX *ctx, OSSL_CMP_certConf_cb_t cb); 149 int OSSL_CMP_CTX_set_certConf_cb_arg(OSSL_CMP_CTX *ctx, void *arg); 150 void *OSSL_CMP_CTX_get_certConf_cb_arg(const OSSL_CMP_CTX *ctx); 151 152 /* result fetching: */ 153 int OSSL_CMP_CTX_get_status(const OSSL_CMP_CTX *ctx); 154 OSSL_CMP_PKIFREETEXT *OSSL_CMP_CTX_get0_statusString(const OSSL_CMP_CTX *ctx); 155 int OSSL_CMP_CTX_get_failInfoCode(const OSSL_CMP_CTX *ctx); 156 157 X509 *OSSL_CMP_CTX_get0_validatedSrvCert(const OSSL_CMP_CTX *ctx); 158 X509 *OSSL_CMP_CTX_get0_newCert(const OSSL_CMP_CTX *ctx); 159 STACK_OF(X509) *OSSL_CMP_CTX_get1_newChain(const OSSL_CMP_CTX *ctx); 160 STACK_OF(X509) *OSSL_CMP_CTX_get1_caPubs(const OSSL_CMP_CTX *ctx); 161 STACK_OF(X509) *OSSL_CMP_CTX_get1_extraCertsIn(const OSSL_CMP_CTX *ctx); 162 163 /* for testing and debugging purposes: */ 164 int OSSL_CMP_CTX_set1_transactionID(OSSL_CMP_CTX *ctx, 165 const ASN1_OCTET_STRING *id); 166 int OSSL_CMP_CTX_set1_senderNonce(OSSL_CMP_CTX *ctx, 167 const ASN1_OCTET_STRING *nonce); 168 169=head1 DESCRIPTION 170 171This is the context API for using CMP (Certificate Management Protocol) with 172OpenSSL. 173 174OSSL_CMP_CTX_new() allocates an B<OSSL_CMP_CTX> structure associated with 175the library context I<libctx> and property query string I<propq>, 176both of which may be NULL to select the defaults. 177It initializes the remaining fields to their default values - for instance, 178the logging verbosity is set to OSSL_CMP_LOG_INFO, 179the message timeout is set to 120 seconds, 180and the proof-of-possession method is set to OSSL_CRMF_POPO_SIGNATURE. 181 182OSSL_CMP_CTX_free() deallocates an OSSL_CMP_CTX structure. 183 184OSSL_CMP_CTX_reinit() prepares the given I<ctx> for a further transaction by 185clearing the internal CMP transaction (aka session) status, PKIStatusInfo, 186and any previous results (newCert, newChain, caPubs, and extraCertsIn) 187from the last executed transaction. 188All other field values (i.e., CMP options) are retained for potential re-use. 189 190OSSL_CMP_CTX_set_option() sets the given value for the given option 191(e.g., OSSL_CMP_OPT_IMPLICIT_CONFIRM) in the given OSSL_CMP_CTX structure. 192 193The following options can be set: 194 195=over 4 196 197=item B<OSSL_CMP_OPT_LOG_VERBOSITY> 198 199 The level of severity needed for actually outputting log messages 200 due to errors, warnings, general info, debugging, etc. 201 Default is OSSL_CMP_LOG_INFO. See also L<OSSL_CMP_log_open(3)>. 202 203=item B<OSSL_CMP_OPT_KEEP_ALIVE> 204 205 If the given value is 0 then HTTP connections are not kept open 206 after receiving a response, which is the default behavior for HTTP 1.0. 207 If the value is 1 or 2 then persistent connections are requested. 208 If the value is 2 then persistent connections are required, 209 i.e., in case the server does not grant them an error occurs. 210 The default value is 1: prefer to keep the connection open. 211 212=item B<OSSL_CMP_OPT_MSG_TIMEOUT> 213 214 Number of seconds (or 0 for infinite) a CMP message round trip is 215 allowed to take before a timeout error is returned. 216 Default is to use the B<OSSL_CMP_OPT_MSG_TIMEOUT> setting. 217 218=item B<OSSL_CMP_OPT_TOTAL_TIMEOUT> 219 220 Maximum total number of seconds an enrollment (including polling) 221 may take. Default is 0 (infinite). 222 223=item B<OSSL_CMP_OPT_VALIDITY_DAYS> 224 225 Number of days new certificates are asked to be valid for. 226 227=item B<OSSL_CMP_OPT_SUBJECTALTNAME_NODEFAULT> 228 229 Do not take default Subject Alternative Names 230 from the reference certificate. 231 232=item B<OSSL_CMP_OPT_SUBJECTALTNAME_CRITICAL> 233 234 Demand that the given Subject Alternative Names are flagged as critical. 235 236=item B<OSSL_CMP_OPT_POLICIES_CRITICAL> 237 238 Demand that the given policies are flagged as critical. 239 240=item B<OSSL_CMP_OPT_POPO_METHOD> 241 242 Select the proof of possession method to use. Possible values are: 243 244 OSSL_CRMF_POPO_NONE - ProofOfPossession field omitted 245 OSSL_CRMF_POPO_RAVERIFIED - assert that the RA has already 246 verified the PoPo 247 OSSL_CRMF_POPO_SIGNATURE - sign a value with private key, 248 which is the default. 249 OSSL_CRMF_POPO_KEYENC - decrypt the encrypted certificate 250 ("indirect method") 251 252 Note that a signature-based POPO can only be produced if a private key 253 is provided as the newPkey or client's pkey component of the CMP context. 254 255=item B<OSSL_CMP_OPT_DIGEST_ALGNID> 256 257 The NID of the digest algorithm to be used in RFC 4210's MSG_SIG_ALG 258 for signature-based message protection and Proof-of-Possession (POPO). 259 Default is SHA256. 260 261=item B<OSSL_CMP_OPT_OWF_ALGNID> 262 The NID of the digest algorithm to be used as one-way function (OWF) 263 in RFC 4210's MSG_MAC_ALG for PBM-based message protection. 264 Default is SHA256. 265 266=item B<OSSL_CMP_OPT_MAC_ALGNID> 267 The NID of the MAC algorithm to be used in RFC 4210's MSG_MAC_ALG 268 for PBM-based message protection. 269 Default is HMAC-SHA1 as per RFC 4210. 270 271=item B<OSSL_CMP_OPT_REVOCATION_REASON> 272 273 The reason code to be included in a Revocation Request (RR); 274 values: 0..10 (RFC 5210, 5.3.1) or -1 for none, which is the default. 275 276=item B<OSSL_CMP_OPT_IMPLICIT_CONFIRM> 277 278 Request server to enable implicit confirm mode, where the client 279 does not need to send confirmation upon receiving the 280 certificate. If the server does not enable implicit confirmation 281 in the return message, then confirmation is sent anyway. 282 283=item B<OSSL_CMP_OPT_DISABLE_CONFIRM> 284 285 Do not confirm enrolled certificates, to cope with broken servers 286 not supporting implicit confirmation correctly. 287B<WARNING:> This setting leads to unspecified behavior and it is meant 288exclusively to allow interoperability with server implementations violating 289RFC 4210. 290 291=item B<OSSL_CMP_OPT_UNPROTECTED_SEND> 292 293 Send messages without CMP-level protection. 294 295=item B<OSSL_CMP_OPT_UNPROTECTED_ERRORS> 296 297 Accept unprotected error responses which are either explicitly 298 unprotected or where protection verification failed. Applies to regular 299 error messages as well as certificate responses (IP/CP/KUP) and 300 revocation responses (RP) with rejection. 301B<WARNING:> This setting leads to unspecified behavior and it is meant 302exclusively to allow interoperability with server implementations violating 303RFC 4210. 304 305=item B<OSSL_CMP_OPT_IGNORE_KEYUSAGE> 306 307 Ignore key usage restrictions in the signer's certificate when 308 validating signature-based protection in received CMP messages. 309 Else, 'digitalSignature' must be allowed by CMP signer certificates. 310 311=item B<OSSL_CMP_OPT_PERMIT_TA_IN_EXTRACERTS_FOR_IR> 312 313 Allow retrieving a trust anchor from extraCerts and using that 314 to validate the certificate chain of an IP message. 315 316=back 317 318OSSL_CMP_CTX_get_option() reads the current value of the given option 319(e.g., OSSL_CMP_OPT_IMPLICIT_CONFIRM) from the given OSSL_CMP_CTX structure. 320 321OSSL_CMP_CTX_set_log_cb() sets in I<ctx> the callback function I<cb> 322for handling error queue entries and logging messages. 323When I<cb> is NULL errors are printed to STDERR (if available, else ignored) 324any log messages are ignored. 325Alternatively, L<OSSL_CMP_log_open(3)> may be used to direct logging to STDOUT. 326 327OSSL_CMP_CTX_set_log_verbosity() is a macro setting the 328OSSL_CMP_OPT_LOG_VERBOSITY context option to the given level. 329 330OSSL_CMP_CTX_print_errors() outputs any entries in the OpenSSL error queue. It 331is similar to L<ERR_print_errors_cb(3)> but uses the CMP log callback function 332if set in the I<ctx> for uniformity with CMP logging if given. Otherwise it uses 333L<ERR_print_errors(3)> to print to STDERR (unless OPENSSL_NO_STDIO is defined). 334 335OSSL_CMP_CTX_set1_serverPath() sets the HTTP path of the CMP server on the host, 336also known as "CMP alias". 337The default is C</>. 338 339OSSL_CMP_CTX_set1_server() sets the given server I<address> 340(which may be a hostname or IP address or NULL) in the given I<ctx>. 341 342OSSL_CMP_CTX_set_serverPort() sets the port of the CMP server to connect to. 343If not used or the I<port> argument is 0 344the default port applies, which is 80 for HTTP and 443 for HTTPS. 345 346OSSL_CMP_CTX_set1_proxy() sets the HTTP proxy to be used for connecting to 347the given CMP server unless overruled by any "no_proxy" settings (see below). 348If TLS is not used this defaults to the value of 349the environment variable C<http_proxy> if set, else C<HTTP_PROXY>. 350Otherwise defaults to the value of C<https_proxy> if set, else C<HTTPS_PROXY>. 351An empty proxy string specifies not to use a proxy. 352Else the format is C<[http[s]://]address[:port][/path]>, 353where any path given is ignored. 354The default port number is 80, or 443 in case C<https:> is given. 355 356OSSL_CMP_CTX_set1_no_proxy() sets the list of server hostnames not to use 357an HTTP proxy for. The names may be separated by commas and/or whitespace. 358Defaults to the environment variable C<no_proxy> if set, else C<NO_PROXY>. 359 360OSSL_CMP_CTX_set_http_cb() sets the optional BIO connect/disconnect callback 361function, which has the prototype 362 363 typedef BIO *(*HTTP_bio_cb_t) (BIO *bio, void *ctx, int connect, int detail); 364 365The callback may modify the I<bio> provided by L<OSSL_CMP_MSG_http_perform(3)>, 366whereby it may make use of a custom defined argument I<ctx> 367stored in the OSSL_CMP_CTX by means of OSSL_CMP_CTX_set_http_cb_arg(). 368During connection establishment, just after calling BIO_do_connect_retry(), 369the function is invoked with the I<connect> argument being 1 and the I<detail> 370argument being 1 if HTTPS is requested, i.e., SSL/TLS should be enabled. On 371disconnect I<connect> is 0 and I<detail> is 1 in case no error occurred, else 0. 372For instance, on connect the function may prepend a TLS BIO to implement HTTPS; 373after disconnect it may do some diagnostic output and/or specific cleanup. 374The function should return NULL to indicate failure. 375After disconnect the modified BIO will be deallocated using BIO_free_all(). 376 377OSSL_CMP_CTX_set_http_cb_arg() sets an argument, respectively a pointer to 378a structure containing arguments, 379optionally to be used by the http connect/disconnect callback function. 380I<arg> is not consumed, and it must therefore explicitly be freed when not 381needed any more. I<arg> may be NULL to clear the entry. 382 383OSSL_CMP_CTX_get_http_cb_arg() gets the argument, respectively the pointer to a 384structure containing arguments, previously set by 385OSSL_CMP_CTX_set_http_cb_arg() or NULL if unset. 386 387OSSL_CMP_CTX_set_transfer_cb() sets the message transfer callback function, 388which has the type 389 390 typedef OSSL_CMP_MSG *(*OSSL_CMP_transfer_cb_t) (OSSL_CMP_CTX *ctx, 391 const OSSL_CMP_MSG *req); 392 393Returns 1 on success, 0 on error. 394 395Default is NULL, which implies the use of L<OSSL_CMP_MSG_http_perform(3)>. 396The callback should send the CMP request message it obtains via the I<req> 397parameter and on success return the response, else it must return NULL. 398The transfer callback may make use of a custom defined argument stored in 399the ctx by means of OSSL_CMP_CTX_set_transfer_cb_arg(), which may be retrieved 400again through OSSL_CMP_CTX_get_transfer_cb_arg(). 401 402OSSL_CMP_CTX_set_transfer_cb_arg() sets an argument, respectively a pointer to a 403structure containing arguments, optionally to be used by the transfer callback. 404I<arg> is not consumed, and it must therefore explicitly be freed when not 405needed any more. I<arg> may be NULL to clear the entry. 406 407OSSL_CMP_CTX_get_transfer_cb_arg() gets the argument, respectively the pointer 408to a structure containing arguments, previously set by 409OSSL_CMP_CTX_set_transfer_cb_arg() or NULL if unset. 410 411OSSL_CMP_CTX_set1_srvCert() sets the expected server cert in I<ctx> and trusts 412it directly (even if it is expired) when verifying signed response messages. 413May be used alternatively to OSSL_CMP_CTX_set0_trusted() 414to pin the accepted server. 415Any previously set value is freed. 416The I<cert> argument may be NULL to clear the entry. 417If set, the subject of the certificate is also used 418as default value for the recipient of CMP requests 419and as default value for the expected sender of CMP responses. 420 421OSSL_CMP_CTX_set1_expected_sender() sets the Distinguished Name (DN) 422expected in the sender field of CMP response messages. 423Defaults to the subject of the pinned server certificate, if any. 424This can be used to make sure that only a particular entity is accepted as 425CMP message signer, and attackers are not able to use arbitrary certificates 426of a trusted PKI hierarchy to fraudulently pose as CMP server. 427Note that this gives slightly more freedom than OSSL_CMP_CTX_set1_srvCert(), 428which pins the server to the holder of a particular certificate, while the 429expected sender name will continue to match after updates of the server cert. 430 431OSSL_CMP_CTX_set0_trusted() is an alias of the original 432OSSL_CMP_CTX_set0_trustedStore(). 433It sets in the CMP context I<ctx> the certificate store of type X509_STORE 434containing trusted (root) CA certificates. 435The store may also hold CRLs and 436a certificate verification callback function used for CMP server authentication. 437Any store entry already set before is freed. 438When given a NULL parameter the entry is cleared. 439 440OSSL_CMP_CTX_get0_trusted() is an alias of the original 441OSSL_CMP_CTX_get0_trustedStore(). 442It extracts from the CMP context I<ctx> the pointer to the currently set 443certificate store containing trusted cert etc., or an empty store if unset. 444 445OSSL_CMP_CTX_set1_untrusted() sets up a list of non-trusted certificates 446of intermediate CAs that may be useful for path construction for the CMP client 447certificate, for the TLS client certificate (if any), when verifying 448the CMP server certificate, and when verifying newly enrolled certificates. 449The reference counts of those certificates handled successfully are increased. 450 451OSSL_CMP_CTX_get0_untrusted(OSSL_CMP_CTX *ctx) returns a pointer to the 452list of untrusted certs, which may be empty if unset. 453 454OSSL_CMP_CTX_set1_cert() sets the certificate related to the client's private key 455used for CMP message protection. 456Therefore the public key of this I<cert> must correspond to 457the private key set before or thereafter via OSSL_CMP_CTX_set1_pkey(). 458When using signature-based protection of CMP request messages 459this CMP signer certificate will be included first in the extraCerts field. 460It serves as fallback reference certificate, see OSSL_CMP_CTX_set1_oldCert(). 461The subject of this I<cert> will be used as the sender field of outgoing 462messages, while the subject of any cert set via OSSL_CMP_CTX_set1_oldCert(), 463the subject of any PKCS#10 CSR set via OSSL_CMP_CTX_set1_p10CSR(), 464and any value set via OSSL_CMP_CTX_set1_subjectName() are used as fallback. 465 466The I<cert> argument may be NULL to clear the entry. 467 468OSSL_CMP_CTX_build_cert_chain() builds a certificate chain for the CMP signer 469certificate previously set in the I<ctx>. It adds the optional I<candidates>, 470a list of intermediate CA certs that may already constitute the targeted chain, 471to the untrusted certs that may already exist in the I<ctx>. 472Then the function uses this augumented set of certs for chain construction. 473If I<own_trusted> is NULL it builds the chain as far down as possible and 474ignores any verification errors. Else the CMP signer certificate must be 475verifiable where the chain reaches a trust anchor contained in I<own_trusted>. 476On success the function stores the resulting chain in I<ctx> 477for inclusion in the extraCerts field of signature-protected messages. 478Calling this function is optional; by default a chain construction 479is performed on demand that is equivalent to calling this function 480with the I<candidates> and I<own_trusted> arguments being NULL. 481 482OSSL_CMP_CTX_set1_pkey() sets the client's private key corresponding to the 483CMP signer certificate set via OSSL_CMP_CTX_set1_cert(). 484This key is used create signature-based protection (protectionAlg = MSG_SIG_ALG) 485of outgoing messages 486unless a PBM secret has been set via OSSL_CMP_CTX_set1_secretValue(). 487The I<pkey> argument may be NULL to clear the entry. 488 489OSSL_CMP_CTX_set1_secretValue() sets the byte string I<sec> with length I<len> 490as PBM secret in the given I<ctx> or clears it if the I<sec> argument is NULL. 491If present, this secret is used to create PBM-based protection of outgoing 492messages and to verify any PBM-based protection of incoming messages 493(protectionAlg = MSG_MAC_ALG). PBM stands for Password-Based MAC. 494PBM-based protection takes precedence over signature-based protection. 495 496OSSL_CMP_CTX_set1_referenceValue() sets the given referenceValue I<ref> with 497length I<len> in the given I<ctx> or clears it if the I<ref> argument is NULL. 498According to RFC 4210 section 5.1.1, if no value for the sender field in 499CMP message headers can be determined (i.e., no CMP signer certificate 500and no subject DN is set via OSSL_CMP_CTX_set1_subjectName() 501then the sender field will contain the NULL-DN 502and the senderKID field of the CMP message header must be set. 503When signature-based protection is used the senderKID will be set to 504the subjectKeyIdentifier of the CMP signer certificate as far as present. 505If not present or when PBM-based protection is used 506the I<ref> value is taken as the fallback value for the senderKID. 507 508OSSL_CMP_CTX_set1_recipient() sets the recipient name that will be used in the 509PKIHeader of CMP request messages, i.e. the X509 name of the (CA) server. 510 511The recipient field in the header of a CMP message is mandatory. 512If not given explicitly the recipient is determined in the following order: 513the subject of the CMP server certificate set using OSSL_CMP_CTX_set1_srvCert(), 514the value set using OSSL_CMP_CTX_set1_issuer(), 515the issuer of the certificate set using OSSL_CMP_CTX_set1_oldCert(), 516the issuer of the CMP signer certificate, 517as far as any of those is present, else the NULL-DN as last resort. 518 519OSSL_CMP_CTX_push0_geninfo_ITAV() adds I<itav> to the stack in the I<ctx> to be 520added to the GeneralInfo field of the CMP PKIMessage header of a request 521message sent with this context. 522 523OSSL_CMP_CTX_set1_extraCertsOut() sets the stack of extraCerts that will be 524sent to remote. 525 526OSSL_CMP_CTX_set0_newPkey() can be used to explicitly set the given EVP_PKEY 527structure as the private or public key to be certified in the CMP context. 528The I<priv> parameter must be 0 if and only if the given key is a public key. 529 530OSSL_CMP_CTX_get0_newPkey() gives the key to use for certificate enrollment 531dependent on fields of the CMP context structure: 532the newPkey (which may be a private or public key) if present, 533else the public key in the p10CSR if present, else the client's private key. 534If the I<priv> parameter is not 0 and the selected key does not have a 535private component then NULL is returned. 536 537OSSL_CMP_CTX_set1_issuer() sets the name of the intended issuer that 538will be set in the CertTemplate, i.e., the X509 name of the CA server. 539 540OSSL_CMP_CTX_set1_subjectName() sets the subject DN that will be used in 541the CertTemplate structure when requesting a new cert. For Key Update Requests 542(KUR), it defaults to the subject DN of the reference certificate, 543see OSSL_CMP_CTX_set1_oldCert(). This default is used for Initialization 544Requests (IR) and Certification Requests (CR) only if no SANs are set. 545The I<subjectName> is also used as fallback for the sender field 546of outgoing CMP messages if no reference certificate is available. 547 548OSSL_CMP_CTX_push1_subjectAltName() adds the given X509 name to the list of 549alternate names on the certificate template request. This cannot be used if 550any Subject Alternative Name extension is set via 551OSSL_CMP_CTX_set0_reqExtensions(). 552By default, unless B<OSSL_CMP_OPT_SUBJECTALTNAME_NODEFAULT> has been set, 553the Subject Alternative Names are copied from the reference certificate, 554see OSSL_CMP_CTX_set1_oldCert(). 555If set and the subject DN is not set with OSSL_CMP_CTX_set1_subjectName() then 556the certificate template of an IR and CR will not be filled with the default 557subject DN from the reference certificate. 558If a subject DN is desired it needs to be set explicitly with 559OSSL_CMP_CTX_set1_subjectName(). 560 561OSSL_CMP_CTX_set0_reqExtensions() sets the X.509v3 extensions to be used in 562IR/CR/KUR. 563 564OSSL_CMP_CTX_reqExtensions_have_SAN() returns 1 if the context contains 565a Subject Alternative Name extension, else 0 or -1 on error. 566 567OSSL_CMP_CTX_push0_policy() adds the certificate policy info object 568to the X509_EXTENSIONS of the requested certificate template. 569 570OSSL_CMP_CTX_set1_oldCert() sets the old certificate to be updated in 571Key Update Requests (KUR) or to be revoked in Revocation Requests (RR). 572It must be given for RR, else it defaults to the CMP signer certificate. 573The I<reference certificate> determined in this way, if any, is also used for 574deriving default subject DN, public key, Subject Alternative Names, and the 575default issuer entry in the requested certificate template of IR/CR/KUR. 576The subject of the reference certificate is used as the sender field value 577in CMP message headers. 578Its issuer is used as default recipient in CMP message headers. 579 580OSSL_CMP_CTX_set1_p10CSR() sets the PKCS#10 CSR to use in P10CR messages. 581If such a CSR is provided, its subject, public key, and extension fields are 582also used as fallback values for the certificate template of IR/CR/KUR messages. 583 584OSSL_CMP_CTX_push0_genm_ITAV() adds I<itav> to the stack in the I<ctx> which 585will be the body of a General Message sent with this context. 586 587OSSL_CMP_certConf_cb() is the default certificate confirmation callback function. 588If the callback argument is not NULL it must point to a trust store. 589In this case the function checks that the newly enrolled certificate can be 590verified using this trust store and untrusted certificates from the I<ctx>, 591which have been augmented by the list of extraCerts received. 592If the callback argument is NULL the function tries building an approximate 593chain as far as possible using the same untrusted certificates from the I<ctx>, 594and if this fails it takes the received extraCerts as fallback. 595The resulting cert chain can be retrieved using OSSL_CMP_CTX_get1_newChain(). 596 597OSSL_CMP_CTX_set_certConf_cb() sets the callback used for evaluating the newly 598enrolled certificate before the library sends, depending on its result, 599a positive or negative certConf message to the server. The callback has type 600 601 typedef int (*OSSL_CMP_certConf_cb_t) (OSSL_CMP_CTX *ctx, X509 *cert, 602 int fail_info, const char **txt); 603 604and should inspect the certificate it obtains via the I<cert> parameter and may 605overrule the pre-decision given in the I<fail_info> and I<*txt> parameters. 606If it accepts the certificate it must return 0, indicating success. Else it must 607return a bit field reflecting PKIFailureInfo with at least one failure bit and 608may set the I<*txt> output parameter to point to a string constant with more 609detail. The transfer callback may make use of a custom defined argument stored 610in the I<ctx> by means of OSSL_CMP_CTX_set_certConf_cb_arg(), which may be 611retrieved again through OSSL_CMP_CTX_get_certConf_cb_arg(). 612Typically, the callback will check at least that the certificate can be verified 613using a set of trusted certificates. 614It also could compare the subject DN and other fields of the newly 615enrolled certificate with the certificate template of the request. 616 617OSSL_CMP_CTX_set_certConf_cb_arg() sets an argument, respectively a pointer to a 618structure containing arguments, optionally to be used by the certConf callback. 619I<arg> is not consumed, and it must therefore explicitly be freed when not 620needed any more. I<arg> may be NULL to clear the entry. 621 622OSSL_CMP_CTX_get_certConf_cb_arg() gets the argument, respectively the pointer 623to a structure containing arguments, previously set by 624OSSL_CMP_CTX_set_certConf_cb_arg(), or NULL if unset. 625 626OSSL_CMP_CTX_get_status() returns the PKIstatus from the last received 627CertRepMessage or Revocation Response or error message, or -1 if unset. 628For server contexts it returns -2 if a transaction is open, else -1. 629 630OSSL_CMP_CTX_get0_statusString() returns the statusString from the last received 631CertRepMessage or Revocation Response or error message, or NULL if unset. 632 633OSSL_CMP_CTX_get_failInfoCode() returns the error code from the failInfo field 634of the last received CertRepMessage or Revocation Response or error message. 635This is a bit field and the flags for it are specified in the header file 636F<< <openssl/cmp.h> >>. 637The flags start with OSSL_CMP_CTX_FAILINFO, for example: 638OSSL_CMP_CTX_FAILINFO_badAlg. Returns -1 if the failInfoCode field is unset. 639 640OSSL_CMP_CTX_get0_validatedSrvCert() returns 641the successfully validated certificate, if any, that the CMP server used 642in the current transaction for signature-based response message protection, 643or NULL if the server used MAC-based protection. 644The value is relevant only at the end of a successful transaction. 645It may be used to check the authorization of the server based on its cert. 646 647OSSL_CMP_CTX_get0_newCert() returns the pointer to the newly obtained 648certificate in case it is available, else NULL. 649 650OSSL_CMP_CTX_get1_newChain() returns a pointer to a duplicate of the stack of 651X.509 certificates computed by OSSL_CMP_certConf_cb() (if this function has 652been called) on the last received certificate response message IP/CP/KUP. 653 654OSSL_CMP_CTX_get1_caPubs() returns a pointer to a duplicate of the list of 655X.509 certificates in the caPubs field of the last received certificate 656response message (of type IP, CP, or KUP), 657or an empty stack if no caPubs have been received in the current transaction. 658 659OSSL_CMP_CTX_get1_extraCertsIn() returns a pointer to a duplicate of the list 660of X.509 certificates contained in the extraCerts field of the last received 661response message (except for pollRep and PKIConf), or 662an empty stack if no extraCerts have been received in the current transaction. 663 664OSSL_CMP_CTX_set1_transactionID() sets the given transaction ID in the given 665OSSL_CMP_CTX structure. 666 667OSSL_CMP_CTX_set1_senderNonce() stores the last sent sender I<nonce> in 668the I<ctx>. This will be used to validate the recipNonce in incoming messages. 669 670=head1 NOTES 671 672CMP is defined in RFC 4210 (and CRMF in RFC 4211). 673 674=head1 RETURN VALUES 675 676OSSL_CMP_CTX_free() and OSSL_CMP_CTX_print_errors() do not return anything. 677 678OSSL_CMP_CTX_new(), 679OSSL_CMP_CTX_get_http_cb_arg(), 680OSSL_CMP_CTX_get_transfer_cb_arg(), 681OSSL_CMP_CTX_get0_trusted(), 682OSSL_CMP_CTX_get0_untrusted(), 683OSSL_CMP_CTX_get0_newPkey(), 684OSSL_CMP_CTX_get_certConf_cb_arg(), 685OSSL_CMP_CTX_get0_statusString(), 686OSSL_CMP_CTX_get0_validatedSrvCert(), 687OSSL_CMP_CTX_get0_newCert(), 688OSSL_CMP_CTX_get0_newChain(), 689OSSL_CMP_CTX_get1_caPubs(), and 690OSSL_CMP_CTX_get1_extraCertsIn() 691return the intended pointer value as described above or NULL on error. 692 693OSSL_CMP_CTX_get_option(), 694OSSL_CMP_CTX_reqExtensions_have_SAN(), 695OSSL_CMP_CTX_get_status(), and 696OSSL_CMP_CTX_get_failInfoCode() 697return the intended value as described above or -1 on error. 698 699OSSL_CMP_certConf_cb() returns I<fail_info> if it is not equal to 0, 700else 0 on successful validation, 701or else a bit field with the B<OSSL_CMP_PKIFAILUREINFO_incorrectData> bit set. 702 703All other functions return 1 on success, 0 on error. 704 705=head1 EXAMPLES 706 707The following code omits error handling. 708 709Set up a CMP client context for sending requests and verifying responses: 710 711 cmp_ctx = OSSL_CMP_CTX_new(); 712 OSSL_CMP_CTX_set1_server(cmp_ctx, name_or_address); 713 OSSL_CMP_CTX_set1_serverPort(cmp_ctx, port_string); 714 OSSL_CMP_CTX_set1_serverPath(cmp_ctx, path_or_alias); 715 OSSL_CMP_CTX_set0_trusted(cmp_ctx, ts); 716 717Set up client credentials for password-based protection (PBM): 718 719 OSSL_CMP_CTX_set1_referenceValue(cmp_ctx, ref, ref_len); 720 OSSL_CMP_CTX_set1_secretValue(cmp_ctx, sec, sec_len); 721 722Set up the details for certificate requests: 723 724 OSSL_CMP_CTX_set1_subjectName(cmp_ctx, name); 725 OSSL_CMP_CTX_set0_newPkey(cmp_ctx, 1, initialKey); 726 727Perform an Initialization Request transaction: 728 729 initialCert = OSSL_CMP_exec_IR_ses(cmp_ctx); 730 731Reset the transaction state of the CMP context and the credentials: 732 733 OSSL_CMP_CTX_reinit(cmp_ctx); 734 OSSL_CMP_CTX_set1_referenceValue(cmp_ctx, NULL, 0); 735 OSSL_CMP_CTX_set1_secretValue(cmp_ctx, NULL, 0); 736 737Perform a Certification Request transaction, making use of the new credentials: 738 739 OSSL_CMP_CTX_set1_cert(cmp_ctx, initialCert); 740 OSSL_CMP_CTX_set1_pkey(cmp_ctx, initialKey); 741 OSSL_CMP_CTX_set0_newPkey(cmp_ctx, 1, curentKey); 742 currentCert = OSSL_CMP_exec_CR_ses(cmp_ctx); 743 744Perform a Key Update Request, signed using the cert (and key) to be updated: 745 746 OSSL_CMP_CTX_reinit(cmp_ctx); 747 OSSL_CMP_CTX_set1_cert(cmp_ctx, currentCert); 748 OSSL_CMP_CTX_set1_pkey(cmp_ctx, currentKey); 749 OSSL_CMP_CTX_set0_newPkey(cmp_ctx, 1, updatedKey); 750 currentCert = OSSL_CMP_exec_KUR_ses(cmp_ctx); 751 currentKey = updatedKey; 752 753Perform a General Message transaction including, as an example, 754the id-it-signKeyPairTypes OID and prints info on the General Response contents: 755 756 OSSL_CMP_CTX_reinit(cmp_ctx); 757 758 ASN1_OBJECT *type = OBJ_txt2obj("1.3.6.1.5.5.7.4.2", 1); 759 OSSL_CMP_ITAV *itav = OSSL_CMP_ITAV_new(type, NULL); 760 OSSL_CMP_CTX_push0_genm_ITAV(cmp_ctx, itav); 761 762 STACK_OF(OSSL_CMP_ITAV) *itavs; 763 itavs = OSSL_CMP_exec_GENM_ses(cmp_ctx); 764 print_itavs(itavs); 765 sk_OSSL_CMP_ITAV_pop_free(itavs, OSSL_CMP_ITAV_free); 766 767=head1 SEE ALSO 768 769L<OSSL_CMP_exec_IR_ses(3)>, L<OSSL_CMP_exec_CR_ses(3)>, 770L<OSSL_CMP_exec_KUR_ses(3)>, L<OSSL_CMP_exec_GENM_ses(3)>, 771L<OSSL_CMP_exec_certreq(3)>, L<OSSL_CMP_MSG_http_perform(3)>, 772L<ERR_print_errors_cb(3)> 773 774=head1 HISTORY 775 776The OpenSSL CMP support was added in OpenSSL 3.0. 777 778OSSL_CMP_CTX_get0_trustedStore() was renamed to OSSL_CMP_CTX_get0_trusted() and 779OSSL_CMP_CTX_set0_trustedStore() was renamed to OSSL_CMP_CTX_set0_trusted(), 780using macros, while keeping the old names for backward compatibility, 781in OpenSSL 3.1. 782 783OSSL_CMP_CTX_get0_validatedSrvCert() was added in OpenSSL 3.1. 784 785=head1 COPYRIGHT 786 787Copyright 2007-2022 The OpenSSL Project Authors. All Rights Reserved. 788 789Licensed under the Apache License 2.0 (the "License"). You may not use 790this file except in compliance with the License. You can obtain a copy 791in the file LICENSE in the source distribution or at 792L<https://www.openssl.org/source/license.html>. 793 794=cut 795
