crypto/crmf/crmf_lib.c

   1 /*-
   2  * Copyright 2007-2021 The OpenSSL Project Authors. All Rights Reserved.
   3  * Copyright Nokia 2007-2018
   4  * Copyright Siemens AG 2015-2019
   5  *
   6  * Licensed under the Apache License 2.0 (the "License").  You may not use
   7  * this file except in compliance with the License.  You can obtain a copy
   8  * in the file LICENSE in the source distribution or at
   9  * https://www.openssl.org/source/license.html
  10  *
  11  * CRMF implementation by Martin Peylo, Miikka Viljanen, and David von Oheimb.
  12  */
  13
  14 /*
  15  * This file contains the functions that handle the individual items inside
  16  * the CRMF structures
  17  */
  18
  19 /*
  20  * NAMING
  21  *
  22  * The 0 functions use the supplied structure pointer directly in the parent and
  23  * it will be freed up when the parent is freed.
  24  *
  25  * The 1 functions use a copy of the supplied structure pointer (or in some
  26  * cases increases its link count) in the parent and so both should be freed up.
  27  */
  28
  29 #include <openssl/asn1t.h>
  30
  31 #include "crmf_local.h"
  32 #include "internal/constant_time.h"
  33 #include "internal/sizes.h"
  34
  35 /* explicit #includes not strictly needed since implied by the above: */
  36 #include <openssl/crmf.h>
  37 #include <openssl/err.h>
  38 #include <openssl/evp.h>
  39
  40 /*-
  41  * atyp = Attribute Type
  42  * valt = Value Type
  43  * ctrlinf = "regCtrl" or "regInfo"
  44  */
  45 #define IMPLEMENT_CRMF_CTRL_FUNC(atyp, valt, ctrlinf)                        \
  46 valt *OSSL_CRMF_MSG_get0_##ctrlinf##_##atyp(const OSSL_CRMF_MSG *msg)        \
  47 {                                                                            \
  48     int i;                                                                   \
  49     STACK_OF(OSSL_CRMF_ATTRIBUTETYPEANDVALUE) *controls;                     \
  50     OSSL_CRMF_ATTRIBUTETYPEANDVALUE *atav = NULL;                            \
  51                                                                              \
  52     if (msg == NULL || msg->certReq == NULL)                                 \
  53         return NULL;                                                         \
  54     controls = msg->certReq->controls;                                       \
  55     for (i = 0; i < sk_OSSL_CRMF_ATTRIBUTETYPEANDVALUE_num(controls); i++) { \
  56         atav = sk_OSSL_CRMF_ATTRIBUTETYPEANDVALUE_value(controls, i);        \
  57         if (OBJ_obj2nid(atav->type) == NID_id_##ctrlinf##_##atyp)            \
  58             return atav->value.atyp;                                         \
  59     }                                                                        \
  60     return NULL;                                                             \
  61 }                                                                            \
  62  \
  63 int OSSL_CRMF_MSG_set1_##ctrlinf##_##atyp(OSSL_CRMF_MSG *msg, const valt *in) \
  64 {                                                                         \
  65     OSSL_CRMF_ATTRIBUTETYPEANDVALUE *atav = NULL;                         \
  66                                                                           \
  67     if (msg == NULL || in == NULL)                                        \
  68         goto err;                                                         \
  69     if ((atav = OSSL_CRMF_ATTRIBUTETYPEANDVALUE_new()) == NULL)           \
  70         goto err;                                                         \
  71     if ((atav->type = OBJ_nid2obj(NID_id_##ctrlinf##_##atyp)) == NULL)    \
  72         goto err;                                                         \
  73     if ((atav->value.atyp = valt##_dup(in)) == NULL)                      \
  74         goto err;                                                         \
  75     if (!OSSL_CRMF_MSG_push0_##ctrlinf(msg, atav))                        \
  76         goto err;                                                         \
  77     return 1;                                                             \
  78  err:                                                                     \
  79     OSSL_CRMF_ATTRIBUTETYPEANDVALUE_free(atav);                           \
  80     return 0;                                                             \
  81 }
  82
  83
  84 /*-
  85  * Pushes the given control attribute into the controls stack of a CertRequest
  86  * (section 6)
  87  * returns 1 on success, 0 on error
  88  */
  89 static int OSSL_CRMF_MSG_push0_regCtrl(OSSL_CRMF_MSG *crm,
  90                                        OSSL_CRMF_ATTRIBUTETYPEANDVALUE *ctrl)
  91 {
  92     int new = 0;
  93
  94     if (crm == NULL || crm->certReq == NULL || ctrl == NULL) {
  95         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
  96         return 0;
  97     }
  98
  99     if (crm->certReq->controls == NULL) {
 100         crm->certReq->controls = sk_OSSL_CRMF_ATTRIBUTETYPEANDVALUE_new_null();
 101         if (crm->certReq->controls == NULL)
 102             goto err;
 103         new = 1;
 104     }
 105     if (!sk_OSSL_CRMF_ATTRIBUTETYPEANDVALUE_push(crm->certReq->controls, ctrl))
 106         goto err;
 107
 108     return 1;
 109  err:
 110     if (new != 0) {
 111         sk_OSSL_CRMF_ATTRIBUTETYPEANDVALUE_free(crm->certReq->controls);
 112         crm->certReq->controls = NULL;
 113     }
 114     return 0;
 115 }
 116
 117 /* id-regCtrl-regToken Control (section 6.1) */
 118 IMPLEMENT_CRMF_CTRL_FUNC(regToken, ASN1_STRING, regCtrl)
 119
 120 /* id-regCtrl-authenticator Control (section 6.2) */
 121 #define ASN1_UTF8STRING_dup ASN1_STRING_dup
 122 IMPLEMENT_CRMF_CTRL_FUNC(authenticator, ASN1_UTF8STRING, regCtrl)
 123
 124 int OSSL_CRMF_MSG_set0_SinglePubInfo(OSSL_CRMF_SINGLEPUBINFO *spi,
 125                                      int method, GENERAL_NAME *nm)
 126 {
 127     if (spi == NULL
 128             || method < OSSL_CRMF_PUB_METHOD_DONTCARE
 129             || method > OSSL_CRMF_PUB_METHOD_LDAP) {
 130         ERR_raise(ERR_LIB_CRMF, ERR_R_PASSED_INVALID_ARGUMENT);
 131         return 0;
 132     }
 133
 134     if (!ASN1_INTEGER_set(spi->pubMethod, method))
 135         return 0;
 136     GENERAL_NAME_free(spi->pubLocation);
 137     spi->pubLocation = nm;
 138     return 1;
 139 }
 140
 141 int
 142 OSSL_CRMF_MSG_PKIPublicationInfo_push0_SinglePubInfo(OSSL_CRMF_PKIPUBLICATIONINFO *pi,
 143                                                      OSSL_CRMF_SINGLEPUBINFO *spi)
 144 {
 145     if (pi == NULL || spi == NULL) {
 146         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 147         return 0;
 148     }
 149     if (pi->pubInfos == NULL)
 150         pi->pubInfos = sk_OSSL_CRMF_SINGLEPUBINFO_new_null();
 151     if (pi->pubInfos == NULL)
 152         return 0;
 153
 154     return sk_OSSL_CRMF_SINGLEPUBINFO_push(pi->pubInfos, spi);
 155 }
 156
 157 int OSSL_CRMF_MSG_set_PKIPublicationInfo_action(OSSL_CRMF_PKIPUBLICATIONINFO *pi,
 158                                                 int action)
 159 {
 160     if (pi == NULL
 161             || action < OSSL_CRMF_PUB_ACTION_DONTPUBLISH
 162             || action > OSSL_CRMF_PUB_ACTION_PLEASEPUBLISH) {
 163         ERR_raise(ERR_LIB_CRMF, ERR_R_PASSED_INVALID_ARGUMENT);
 164         return 0;
 165     }
 166
 167     return ASN1_INTEGER_set(pi->action, action);
 168 }
 169
 170 /* id-regCtrl-pkiPublicationInfo Control (section 6.3) */
 171 IMPLEMENT_CRMF_CTRL_FUNC(pkiPublicationInfo, OSSL_CRMF_PKIPUBLICATIONINFO,
 172                          regCtrl)
 173
 174 /* id-regCtrl-oldCertID Control (section 6.5) from the given */
 175 IMPLEMENT_CRMF_CTRL_FUNC(oldCertID, OSSL_CRMF_CERTID, regCtrl)
 176
 177 OSSL_CRMF_CERTID *OSSL_CRMF_CERTID_gen(const X509_NAME *issuer,
 178                                        const ASN1_INTEGER *serial)
 179 {
 180     OSSL_CRMF_CERTID *cid = NULL;
 181
 182     if (issuer == NULL || serial == NULL) {
 183         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 184         return NULL;
 185     }
 186
 187     if ((cid = OSSL_CRMF_CERTID_new()) == NULL)
 188         goto err;
 189
 190     if (!X509_NAME_set(&cid->issuer->d.directoryName, issuer))
 191         goto err;
 192     cid->issuer->type = GEN_DIRNAME;
 193
 194     ASN1_INTEGER_free(cid->serialNumber);
 195     if ((cid->serialNumber = ASN1_INTEGER_dup(serial)) == NULL)
 196         goto err;
 197
 198     return cid;
 199
 200  err:
 201     OSSL_CRMF_CERTID_free(cid);
 202     return NULL;
 203 }
 204
 205 /*
 206  * id-regCtrl-protocolEncrKey Control (section 6.6)
 207  */
 208 IMPLEMENT_CRMF_CTRL_FUNC(protocolEncrKey, X509_PUBKEY, regCtrl)
 209
 210 /*-
 211  * Pushes the attribute given in regInfo in to the CertReqMsg->regInfo stack.
 212  * (section 7)
 213  * returns 1 on success, 0 on error
 214  */
 215 static int OSSL_CRMF_MSG_push0_regInfo(OSSL_CRMF_MSG *crm,
 216                                        OSSL_CRMF_ATTRIBUTETYPEANDVALUE *ri)
 217 {
 218     STACK_OF(OSSL_CRMF_ATTRIBUTETYPEANDVALUE) *info = NULL;
 219
 220     if (crm == NULL || ri == NULL) {
 221         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 222         return 0;
 223     }
 224
 225     if (crm->regInfo == NULL)
 226         crm->regInfo = info = sk_OSSL_CRMF_ATTRIBUTETYPEANDVALUE_new_null();
 227     if (crm->regInfo == NULL)
 228         goto err;
 229     if (!sk_OSSL_CRMF_ATTRIBUTETYPEANDVALUE_push(crm->regInfo, ri))
 230         goto err;
 231     return 1;
 232
 233  err:
 234     if (info != NULL)
 235         crm->regInfo = NULL;
 236     sk_OSSL_CRMF_ATTRIBUTETYPEANDVALUE_free(info);
 237     return 0;
 238 }
 239
 240 /* id-regInfo-utf8Pairs to regInfo (section 7.1) */
 241 IMPLEMENT_CRMF_CTRL_FUNC(utf8Pairs, ASN1_UTF8STRING, regInfo)
 242
 243 /* id-regInfo-certReq to regInfo (section 7.2) */
 244 IMPLEMENT_CRMF_CTRL_FUNC(certReq, OSSL_CRMF_CERTREQUEST, regInfo)
 245
 246
 247 /* retrieves the certificate template of crm */
 248 OSSL_CRMF_CERTTEMPLATE *OSSL_CRMF_MSG_get0_tmpl(const OSSL_CRMF_MSG *crm)
 249 {
 250     if (crm == NULL || crm->certReq == NULL) {
 251         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 252         return NULL;
 253     }
 254     return crm->certReq->certTemplate;
 255 }
 256
 257
 258 int OSSL_CRMF_MSG_set0_validity(OSSL_CRMF_MSG *crm,
 259                                 ASN1_TIME *notBefore, ASN1_TIME *notAfter)
 260 {
 261     OSSL_CRMF_OPTIONALVALIDITY *vld;
 262     OSSL_CRMF_CERTTEMPLATE *tmpl = OSSL_CRMF_MSG_get0_tmpl(crm);
 263
 264     if (tmpl == NULL) { /* also crm == NULL implies this */
 265         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 266         return 0;
 267     }
 268
 269     if ((vld = OSSL_CRMF_OPTIONALVALIDITY_new()) == NULL)
 270         return 0;
 271     vld->notBefore = notBefore;
 272     vld->notAfter = notAfter;
 273     tmpl->validity = vld;
 274     return 1;
 275 }
 276
 277
 278 int OSSL_CRMF_MSG_set_certReqId(OSSL_CRMF_MSG *crm, int rid)
 279 {
 280     if (crm == NULL || crm->certReq == NULL || crm->certReq->certReqId == NULL) {
 281         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 282         return 0;
 283     }
 284
 285     return ASN1_INTEGER_set(crm->certReq->certReqId, rid);
 286 }
 287
 288 /* get ASN.1 encoded integer, return -1 on error */
 289 static int crmf_asn1_get_int(const ASN1_INTEGER *a)
 290 {
 291     int64_t res;
 292
 293     if (!ASN1_INTEGER_get_int64(&res, a)) {
 294         ERR_raise(ERR_LIB_CRMF, ASN1_R_INVALID_NUMBER);
 295         return -1;
 296     }
 297     if (res < INT_MIN) {
 298         ERR_raise(ERR_LIB_CRMF, ASN1_R_TOO_SMALL);
 299         return -1;
 300     }
 301     if (res > INT_MAX) {
 302         ERR_raise(ERR_LIB_CRMF, ASN1_R_TOO_LARGE);
 303         return -1;
 304     }
 305     return (int)res;
 306 }
 307
 308 int OSSL_CRMF_MSG_get_certReqId(const OSSL_CRMF_MSG *crm)
 309 {
 310     if (crm == NULL || /* not really needed: */ crm->certReq == NULL) {
 311         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 312         return -1;
 313     }
 314     return crmf_asn1_get_int(crm->certReq->certReqId);
 315 }
 316
 317
 318 int OSSL_CRMF_MSG_set0_extensions(OSSL_CRMF_MSG *crm,
 319                                   X509_EXTENSIONS *exts)
 320 {
 321     OSSL_CRMF_CERTTEMPLATE *tmpl = OSSL_CRMF_MSG_get0_tmpl(crm);
 322
 323     if (tmpl == NULL) { /* also crm == NULL implies this */
 324         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 325         return 0;
 326     }
 327
 328     if (sk_X509_EXTENSION_num(exts) == 0) {
 329         sk_X509_EXTENSION_free(exts);
 330         exts = NULL; /* do not include empty extensions list */
 331     }
 332
 333     sk_X509_EXTENSION_pop_free(tmpl->extensions, X509_EXTENSION_free);
 334     tmpl->extensions = exts;
 335     return 1;
 336 }
 337
 338
 339 int OSSL_CRMF_MSG_push0_extension(OSSL_CRMF_MSG *crm,
 340                                   X509_EXTENSION *ext)
 341 {
 342     int new = 0;
 343     OSSL_CRMF_CERTTEMPLATE *tmpl = OSSL_CRMF_MSG_get0_tmpl(crm);
 344
 345     if (tmpl == NULL || ext == NULL) { /* also crm == NULL implies this */
 346         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 347         return 0;
 348     }
 349
 350     if (tmpl->extensions == NULL) {
 351         if ((tmpl->extensions = sk_X509_EXTENSION_new_null()) == NULL)
 352             goto err;
 353         new = 1;
 354     }
 355
 356     if (!sk_X509_EXTENSION_push(tmpl->extensions, ext))
 357         goto err;
 358     return 1;
 359  err:
 360     if (new != 0) {
 361         sk_X509_EXTENSION_free(tmpl->extensions);
 362         tmpl->extensions = NULL;
 363     }
 364     return 0;
 365 }
 366
 367 static int create_popo_signature(OSSL_CRMF_POPOSIGNINGKEY *ps,
 368                                  const OSSL_CRMF_CERTREQUEST *cr,
 369                                  EVP_PKEY *pkey, const EVP_MD *digest,
 370                                  OSSL_LIB_CTX *libctx, const char *propq)
 371 {
 372     char name[80] = "";
 373
 374     if (ps == NULL || cr == NULL || pkey == NULL) {
 375         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 376         return 0;
 377     }
 378     if (ps->poposkInput != NULL) {
 379         /* We do not support cases 1+2 defined in RFC 4211, section 4.1 */
 380         ERR_raise(ERR_LIB_CRMF, CRMF_R_POPOSKINPUT_NOT_SUPPORTED);
 381         return 0;
 382     }
 383
 384     if (EVP_PKEY_get_default_digest_name(pkey, name, sizeof(name)) > 0
 385             && strcmp(name, "UNDEF") == 0) /* at least for Ed25519, Ed448 */
 386         digest = NULL;
 387
 388     return ASN1_item_sign_ex(ASN1_ITEM_rptr(OSSL_CRMF_CERTREQUEST),
 389                              ps->algorithmIdentifier, NULL, ps->signature, cr,
 390                              NULL, pkey, digest, libctx, propq);
 391 }
 392
 393
 394 int OSSL_CRMF_MSG_create_popo(int meth, OSSL_CRMF_MSG *crm,
 395                               EVP_PKEY *pkey, const EVP_MD *digest,
 396                               OSSL_LIB_CTX *libctx, const char *propq)
 397 {
 398     OSSL_CRMF_POPO *pp = NULL;
 399     ASN1_INTEGER *tag = NULL;
 400
 401     if (crm == NULL || (meth == OSSL_CRMF_POPO_SIGNATURE && pkey == NULL)) {
 402         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 403         return 0;
 404     }
 405
 406     if (meth == OSSL_CRMF_POPO_NONE)
 407         goto end;
 408     if ((pp = OSSL_CRMF_POPO_new()) == NULL)
 409         goto err;
 410     pp->type = meth;
 411
 412     switch (meth) {
 413     case OSSL_CRMF_POPO_RAVERIFIED:
 414         if ((pp->value.raVerified = ASN1_NULL_new()) == NULL)
 415             goto err;
 416         break;
 417
 418     case OSSL_CRMF_POPO_SIGNATURE:
 419         {
 420             OSSL_CRMF_POPOSIGNINGKEY *ps = OSSL_CRMF_POPOSIGNINGKEY_new();
 421
 422             if (ps == NULL)
 423                 goto err;
 424             if (!create_popo_signature(ps, crm->certReq, pkey, digest,
 425                                        libctx, propq)) {
 426                 OSSL_CRMF_POPOSIGNINGKEY_free(ps);
 427                 goto err;
 428             }
 429             pp->value.signature = ps;
 430         }
 431         break;
 432
 433     case OSSL_CRMF_POPO_KEYENC:
 434         if ((pp->value.keyEncipherment = OSSL_CRMF_POPOPRIVKEY_new()) == NULL)
 435             goto err;
 436         tag = ASN1_INTEGER_new();
 437         pp->value.keyEncipherment->type =
 438             OSSL_CRMF_POPOPRIVKEY_SUBSEQUENTMESSAGE;
 439         pp->value.keyEncipherment->value.subsequentMessage = tag;
 440         if (tag == NULL
 441                 || !ASN1_INTEGER_set(tag, OSSL_CRMF_SUBSEQUENTMESSAGE_ENCRCERT))
 442             goto err;
 443         break;
 444
 445     default:
 446         ERR_raise(ERR_LIB_CRMF, CRMF_R_UNSUPPORTED_METHOD_FOR_CREATING_POPO);
 447         goto err;
 448     }
 449
 450  end:
 451     OSSL_CRMF_POPO_free(crm->popo);
 452     crm->popo = pp;
 453
 454     return 1;
 455  err:
 456     OSSL_CRMF_POPO_free(pp);
 457     return 0;
 458 }
 459
 460 /* verifies the Proof-of-Possession of the request with the given rid in reqs */
 461 int OSSL_CRMF_MSGS_verify_popo(const OSSL_CRMF_MSGS *reqs,
 462                                int rid, int acceptRAVerified,
 463                                OSSL_LIB_CTX *libctx, const char *propq)
 464 {
 465     OSSL_CRMF_MSG *req = NULL;
 466     X509_PUBKEY *pubkey = NULL;
 467     OSSL_CRMF_POPOSIGNINGKEY *sig = NULL;
 468     const ASN1_ITEM *it;
 469     void *asn;
 470
 471     if (reqs == NULL || (req = sk_OSSL_CRMF_MSG_value(reqs, rid)) == NULL) {
 472         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 473         return 0;
 474     }
 475
 476     if (req->popo == NULL) {
 477         ERR_raise(ERR_LIB_CRMF, CRMF_R_POPO_MISSING);
 478         return 0;
 479     }
 480
 481     switch (req->popo->type) {
 482     case OSSL_CRMF_POPO_RAVERIFIED:
 483         if (!acceptRAVerified) {
 484             ERR_raise(ERR_LIB_CRMF, CRMF_R_POPO_RAVERIFIED_NOT_ACCEPTED);
 485             return 0;
 486         }
 487         break;
 488     case OSSL_CRMF_POPO_SIGNATURE:
 489         pubkey = req->certReq->certTemplate->publicKey;
 490         if (pubkey == NULL) {
 491             ERR_raise(ERR_LIB_CRMF, CRMF_R_POPO_MISSING_PUBLIC_KEY);
 492             return 0;
 493         }
 494         sig = req->popo->value.signature;
 495         if (sig->poposkInput != NULL) {
 496             /*
 497              * According to RFC 4211: publicKey contains a copy of
 498              * the public key from the certificate template. This MUST be
 499              * exactly the same value as contained in the certificate template.
 500              */
 501             if (sig->poposkInput->publicKey == NULL) {
 502                 ERR_raise(ERR_LIB_CRMF, CRMF_R_POPO_MISSING_PUBLIC_KEY);
 503                 return 0;
 504             }
 505             if (X509_PUBKEY_eq(pubkey, sig->poposkInput->publicKey) != 1) {
 506                 ERR_raise(ERR_LIB_CRMF, CRMF_R_POPO_INCONSISTENT_PUBLIC_KEY);
 507                 return 0;
 508             }
 509             it = ASN1_ITEM_rptr(OSSL_CRMF_POPOSIGNINGKEYINPUT);
 510             asn = sig->poposkInput;
 511         } else {
 512             if (req->certReq->certTemplate->subject == NULL) {
 513                 ERR_raise(ERR_LIB_CRMF, CRMF_R_POPO_MISSING_SUBJECT);
 514                 return 0;
 515             }
 516             it = ASN1_ITEM_rptr(OSSL_CRMF_CERTREQUEST);
 517             asn = req->certReq;
 518         }
 519         if (ASN1_item_verify_ex(it, sig->algorithmIdentifier, sig->signature,
 520                                 asn, NULL, X509_PUBKEY_get0(pubkey), libctx,
 521                                 propq) < 1)
 522             return 0;
 523         break;
 524     case OSSL_CRMF_POPO_KEYENC:
 525     case OSSL_CRMF_POPO_KEYAGREE:
 526     default:
 527         ERR_raise(ERR_LIB_CRMF, CRMF_R_UNSUPPORTED_POPO_METHOD);
 528         return 0;
 529     }
 530     return 1;
 531 }
 532
 533 /* retrieves the serialNumber of the given cert template or NULL on error */
 534 const ASN1_INTEGER
 535 *OSSL_CRMF_CERTTEMPLATE_get0_serialNumber(const OSSL_CRMF_CERTTEMPLATE *tmpl)
 536 {
 537     return tmpl != NULL ? tmpl->serialNumber : NULL;
 538 }
 539
 540 const X509_NAME
 541     *OSSL_CRMF_CERTTEMPLATE_get0_subject(const OSSL_CRMF_CERTTEMPLATE *tmpl)
 542 {
 543     return tmpl != NULL ? tmpl->subject : NULL;
 544 }
 545
 546 /* retrieves the issuer name of the given cert template or NULL on error */
 547 const X509_NAME
 548     *OSSL_CRMF_CERTTEMPLATE_get0_issuer(const OSSL_CRMF_CERTTEMPLATE *tmpl)
 549 {
 550     return tmpl != NULL ? tmpl->issuer : NULL;
 551 }
 552
 553 X509_EXTENSIONS
 554     *OSSL_CRMF_CERTTEMPLATE_get0_extensions(const OSSL_CRMF_CERTTEMPLATE *tmpl)
 555 {
 556     return tmpl != NULL ? tmpl->extensions : NULL;
 557 }
 558
 559 /* retrieves the issuer name of the given CertId or NULL on error */
 560 const X509_NAME *OSSL_CRMF_CERTID_get0_issuer(const OSSL_CRMF_CERTID *cid)
 561 {
 562     return cid != NULL && cid->issuer->type == GEN_DIRNAME ?
 563         cid->issuer->d.directoryName : NULL;
 564 }
 565
 566 /* retrieves the serialNumber of the given CertId or NULL on error */
 567 const ASN1_INTEGER *OSSL_CRMF_CERTID_get0_serialNumber(const OSSL_CRMF_CERTID *cid)
 568 {
 569     return cid != NULL ? cid->serialNumber : NULL;
 570 }
 571
 572 /*-
 573  * fill in certificate template.
 574  * Any value argument that is NULL will leave the respective field unchanged.
 575  */
 576 int OSSL_CRMF_CERTTEMPLATE_fill(OSSL_CRMF_CERTTEMPLATE *tmpl,
 577                                 EVP_PKEY *pubkey,
 578                                 const X509_NAME *subject,
 579                                 const X509_NAME *issuer,
 580                                 const ASN1_INTEGER *serial)
 581 {
 582     if (tmpl == NULL) {
 583         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 584         return 0;
 585     }
 586     if (subject != NULL && !X509_NAME_set((X509_NAME **)&tmpl->subject, subject))
 587         return 0;
 588     if (issuer != NULL && !X509_NAME_set((X509_NAME **)&tmpl->issuer, issuer))
 589         return 0;
 590     if (serial != NULL) {
 591         ASN1_INTEGER_free(tmpl->serialNumber);
 592         if ((tmpl->serialNumber = ASN1_INTEGER_dup(serial)) == NULL)
 593             return 0;
 594     }
 595     if (pubkey != NULL && !X509_PUBKEY_set(&tmpl->publicKey, pubkey))
 596         return 0;
 597     return 1;
 598 }
 599
 600
 601 /*-
 602  * Decrypts the certificate in the given encryptedValue using private key pkey.
 603  * This is needed for the indirect PoP method as in RFC 4210 section 5.2.8.2.
 604  *
 605  * returns a pointer to the decrypted certificate
 606  * returns NULL on error or if no certificate available
 607  */
 608 X509
 609 *OSSL_CRMF_ENCRYPTEDVALUE_get1_encCert(const OSSL_CRMF_ENCRYPTEDVALUE *ecert,
 610                                        OSSL_LIB_CTX *libctx, const char *propq,
 611                                        EVP_PKEY *pkey)
 612 {
 613     X509 *cert = NULL; /* decrypted certificate */
 614     EVP_CIPHER_CTX *evp_ctx = NULL; /* context for symmetric encryption */
 615     unsigned char *ek = NULL; /* decrypted symmetric encryption key */
 616     size_t eksize = 0; /* size of decrypted symmetric encryption key */
 617     EVP_CIPHER *cipher = NULL; /* used cipher */
 618     int cikeysize = 0; /* key size from cipher */
 619     unsigned char *iv = NULL; /* initial vector for symmetric encryption */
 620     unsigned char *outbuf = NULL; /* decryption output buffer */
 621     const unsigned char *p = NULL; /* needed for decoding ASN1 */
 622     int n, outlen = 0;
 623     EVP_PKEY_CTX *pkctx = NULL; /* private key context */
 624     char name[OSSL_MAX_NAME_SIZE];
 625
 626     if (ecert == NULL || ecert->symmAlg == NULL || ecert->encSymmKey == NULL
 627             || ecert->encValue == NULL || pkey == NULL) {
 628         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 629         return NULL;
 630     }
 631
 632     /* select symmetric cipher based on algorithm given in message */
 633     OBJ_obj2txt(name, sizeof(name), ecert->symmAlg->algorithm, 0);
 634
 635     (void)ERR_set_mark();
 636     cipher = EVP_CIPHER_fetch(NULL, name, NULL);
 637
 638     if (cipher == NULL)
 639         cipher = (EVP_CIPHER *)EVP_get_cipherbyname(name);
 640
 641     if (cipher == NULL) {
 642         (void)ERR_clear_last_mark();
 643         ERR_raise(ERR_LIB_CRMF, CRMF_R_UNSUPPORTED_CIPHER);
 644         goto end;
 645     }
 646     (void)ERR_pop_to_mark();
 647
 648     cikeysize = EVP_CIPHER_get_key_length(cipher);
 649     /* first the symmetric key needs to be decrypted */
 650     pkctx = EVP_PKEY_CTX_new_from_pkey(libctx, pkey, propq);
 651     if (pkctx != NULL && EVP_PKEY_decrypt_init(pkctx)) {
 652         ASN1_BIT_STRING *encKey = ecert->encSymmKey;
 653         size_t failure;
 654         int retval;
 655
 656         if (EVP_PKEY_decrypt(pkctx, NULL, &eksize,
 657                              encKey->data, encKey->length) <= 0
 658                 || (ek = OPENSSL_malloc(eksize)) == NULL)
 659             goto end;
 660         retval = EVP_PKEY_decrypt(pkctx, ek, &eksize,
 661                                   encKey->data, encKey->length);
 662         ERR_clear_error(); /* error state may have sensitive information */
 663         failure = ~constant_time_is_zero_s(constant_time_msb(retval)
 664                                            | constant_time_is_zero(retval));
 665         failure |= ~constant_time_eq_s(eksize, (size_t)cikeysize);
 666         if (failure) {
 667             ERR_raise(ERR_LIB_CRMF, CRMF_R_ERROR_DECRYPTING_SYMMETRIC_KEY);
 668             goto end;
 669         }
 670     } else {
 671         goto end;
 672     }
 673     if ((iv = OPENSSL_malloc(EVP_CIPHER_get_iv_length(cipher))) == NULL)
 674         goto end;
 675     if (ASN1_TYPE_get_octetstring(ecert->symmAlg->parameter, iv,
 676                                   EVP_CIPHER_get_iv_length(cipher))
 677         != EVP_CIPHER_get_iv_length(cipher)) {
 678         ERR_raise(ERR_LIB_CRMF, CRMF_R_MALFORMED_IV);
 679         goto end;
 680     }
 681
 682     /*
 683      * d2i_X509 changes the given pointer, so use p for decoding the message and
 684      * keep the original pointer in outbuf so the memory can be freed later
 685      */
 686     if ((p = outbuf = OPENSSL_malloc(ecert->encValue->length +
 687                                      EVP_CIPHER_get_block_size(cipher))) == NULL
 688             || (evp_ctx = EVP_CIPHER_CTX_new()) == NULL)
 689         goto end;
 690     EVP_CIPHER_CTX_set_padding(evp_ctx, 0);
 691
 692     if (!EVP_DecryptInit(evp_ctx, cipher, ek, iv)
 693             || !EVP_DecryptUpdate(evp_ctx, outbuf, &outlen,
 694                                   ecert->encValue->data,
 695                                   ecert->encValue->length)
 696             || !EVP_DecryptFinal(evp_ctx, outbuf + outlen, &n)) {
 697         ERR_raise(ERR_LIB_CRMF, CRMF_R_ERROR_DECRYPTING_CERTIFICATE);
 698         goto end;
 699     }
 700     outlen += n;
 701
 702     /* convert decrypted certificate from DER to internal ASN.1 structure */
 703     if ((cert = X509_new_ex(libctx, propq)) == NULL)
 704         goto end;
 705     if (d2i_X509(&cert, &p, outlen) == NULL)
 706         ERR_raise(ERR_LIB_CRMF, CRMF_R_ERROR_DECODING_CERTIFICATE);
 707  end:
 708     EVP_PKEY_CTX_free(pkctx);
 709     OPENSSL_free(outbuf);
 710     EVP_CIPHER_CTX_free(evp_ctx);
 711     EVP_CIPHER_free(cipher);
 712     OPENSSL_clear_free(ek, eksize);
 713     OPENSSL_free(iv);
 714     return cert;
 715 }