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     if (ps == NULL || cr == NULL || pkey == NULL) {
 373         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 374         return 0;
 375     }
 376     if (ps->poposkInput != NULL) {
 377         /* We do not support cases 1+2 defined in RFC 4211, section 4.1 */
 378         ERR_raise(ERR_LIB_CRMF, CRMF_R_POPOSKINPUT_NOT_SUPPORTED);
 379         return 0;
 380     }
 381
 382     return ASN1_item_sign_ex(ASN1_ITEM_rptr(OSSL_CRMF_CERTREQUEST),
 383                              ps->algorithmIdentifier, NULL, ps->signature, cr,
 384                              NULL, pkey, digest, libctx, propq);
 385 }
 386
 387
 388 int OSSL_CRMF_MSG_create_popo(int meth, OSSL_CRMF_MSG *crm,
 389                               EVP_PKEY *pkey, const EVP_MD *digest,
 390                               OSSL_LIB_CTX *libctx, const char *propq)
 391 {
 392     OSSL_CRMF_POPO *pp = NULL;
 393     ASN1_INTEGER *tag = NULL;
 394
 395     if (crm == NULL || (meth == OSSL_CRMF_POPO_SIGNATURE && pkey == NULL)) {
 396         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 397         return 0;
 398     }
 399
 400     if (meth == OSSL_CRMF_POPO_NONE)
 401         goto end;
 402     if ((pp = OSSL_CRMF_POPO_new()) == NULL)
 403         goto err;
 404     pp->type = meth;
 405
 406     switch (meth) {
 407     case OSSL_CRMF_POPO_RAVERIFIED:
 408         if ((pp->value.raVerified = ASN1_NULL_new()) == NULL)
 409             goto err;
 410         break;
 411
 412     case OSSL_CRMF_POPO_SIGNATURE:
 413         {
 414             OSSL_CRMF_POPOSIGNINGKEY *ps = OSSL_CRMF_POPOSIGNINGKEY_new();
 415
 416             if (ps == NULL)
 417                 goto err;
 418             if (!create_popo_signature(ps, crm->certReq, pkey, digest,
 419                                        libctx, propq)) {
 420                 OSSL_CRMF_POPOSIGNINGKEY_free(ps);
 421                 goto err;
 422             }
 423             pp->value.signature = ps;
 424         }
 425         break;
 426
 427     case OSSL_CRMF_POPO_KEYENC:
 428         if ((pp->value.keyEncipherment = OSSL_CRMF_POPOPRIVKEY_new()) == NULL)
 429             goto err;
 430         tag = ASN1_INTEGER_new();
 431         pp->value.keyEncipherment->type =
 432             OSSL_CRMF_POPOPRIVKEY_SUBSEQUENTMESSAGE;
 433         pp->value.keyEncipherment->value.subsequentMessage = tag;
 434         if (tag == NULL
 435                 || !ASN1_INTEGER_set(tag, OSSL_CRMF_SUBSEQUENTMESSAGE_ENCRCERT))
 436             goto err;
 437         break;
 438
 439     default:
 440         ERR_raise(ERR_LIB_CRMF, CRMF_R_UNSUPPORTED_METHOD_FOR_CREATING_POPO);
 441         goto err;
 442     }
 443
 444  end:
 445     OSSL_CRMF_POPO_free(crm->popo);
 446     crm->popo = pp;
 447
 448     return 1;
 449  err:
 450     OSSL_CRMF_POPO_free(pp);
 451     return 0;
 452 }
 453
 454 /* verifies the Proof-of-Possession of the request with the given rid in reqs */
 455 int OSSL_CRMF_MSGS_verify_popo(const OSSL_CRMF_MSGS *reqs,
 456                                int rid, int acceptRAVerified,
 457                                OSSL_LIB_CTX *libctx, const char *propq)
 458 {
 459     OSSL_CRMF_MSG *req = NULL;
 460     X509_PUBKEY *pubkey = NULL;
 461     OSSL_CRMF_POPOSIGNINGKEY *sig = NULL;
 462     const ASN1_ITEM *it;
 463     void *asn;
 464
 465     if (reqs == NULL || (req = sk_OSSL_CRMF_MSG_value(reqs, rid)) == NULL) {
 466         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 467         return 0;
 468     }
 469
 470     if (req->popo == NULL) {
 471         ERR_raise(ERR_LIB_CRMF, CRMF_R_POPO_MISSING);
 472         return 0;
 473     }
 474
 475     switch (req->popo->type) {
 476     case OSSL_CRMF_POPO_RAVERIFIED:
 477         if (!acceptRAVerified) {
 478             ERR_raise(ERR_LIB_CRMF, CRMF_R_POPO_RAVERIFIED_NOT_ACCEPTED);
 479             return 0;
 480         }
 481         break;
 482     case OSSL_CRMF_POPO_SIGNATURE:
 483         pubkey = req->certReq->certTemplate->publicKey;
 484         if (pubkey == NULL) {
 485             ERR_raise(ERR_LIB_CRMF, CRMF_R_POPO_MISSING_PUBLIC_KEY);
 486             return 0;
 487         }
 488         sig = req->popo->value.signature;
 489         if (sig->poposkInput != NULL) {
 490             /*
 491              * According to RFC 4211: publicKey contains a copy of
 492              * the public key from the certificate template. This MUST be
 493              * exactly the same value as contained in the certificate template.
 494              */
 495             if (sig->poposkInput->publicKey == NULL) {
 496                 ERR_raise(ERR_LIB_CRMF, CRMF_R_POPO_MISSING_PUBLIC_KEY);
 497                 return 0;
 498             }
 499             if (X509_PUBKEY_eq(pubkey, sig->poposkInput->publicKey) != 1) {
 500                 ERR_raise(ERR_LIB_CRMF, CRMF_R_POPO_INCONSISTENT_PUBLIC_KEY);
 501                 return 0;
 502             }
 503             it = ASN1_ITEM_rptr(OSSL_CRMF_POPOSIGNINGKEYINPUT);
 504             asn = sig->poposkInput;
 505         } else {
 506             if (req->certReq->certTemplate->subject == NULL) {
 507                 ERR_raise(ERR_LIB_CRMF, CRMF_R_POPO_MISSING_SUBJECT);
 508                 return 0;
 509             }
 510             it = ASN1_ITEM_rptr(OSSL_CRMF_CERTREQUEST);
 511             asn = req->certReq;
 512         }
 513         if (ASN1_item_verify_ex(it, sig->algorithmIdentifier, sig->signature,
 514                                 asn, NULL, X509_PUBKEY_get0(pubkey), libctx,
 515                                 propq) < 1)
 516             return 0;
 517         break;
 518     case OSSL_CRMF_POPO_KEYENC:
 519     case OSSL_CRMF_POPO_KEYAGREE:
 520     default:
 521         ERR_raise(ERR_LIB_CRMF, CRMF_R_UNSUPPORTED_POPO_METHOD);
 522         return 0;
 523     }
 524     return 1;
 525 }
 526
 527 /* retrieves the serialNumber of the given cert template or NULL on error */
 528 ASN1_INTEGER
 529 *OSSL_CRMF_CERTTEMPLATE_get0_serialNumber(const OSSL_CRMF_CERTTEMPLATE *tmpl)
 530 {
 531     return tmpl != NULL ? tmpl->serialNumber : NULL;
 532 }
 533
 534 const X509_NAME
 535     *OSSL_CRMF_CERTTEMPLATE_get0_subject(const OSSL_CRMF_CERTTEMPLATE *tmpl)
 536 {
 537     return tmpl != NULL ? tmpl->subject : NULL;
 538 }
 539
 540 /* retrieves the issuer name of the given cert template or NULL on error */
 541 const X509_NAME
 542     *OSSL_CRMF_CERTTEMPLATE_get0_issuer(const OSSL_CRMF_CERTTEMPLATE *tmpl)
 543 {
 544     return tmpl != NULL ? tmpl->issuer : NULL;
 545 }
 546
 547 X509_EXTENSIONS
 548     *OSSL_CRMF_CERTTEMPLATE_get0_extensions(const OSSL_CRMF_CERTTEMPLATE *tmpl)
 549 {
 550     return tmpl != NULL ? tmpl->extensions : NULL;
 551 }
 552
 553 /* retrieves the issuer name of the given CertId or NULL on error */
 554 const X509_NAME *OSSL_CRMF_CERTID_get0_issuer(const OSSL_CRMF_CERTID *cid)
 555 {
 556     return cid != NULL && cid->issuer->type == GEN_DIRNAME ?
 557         cid->issuer->d.directoryName : NULL;
 558 }
 559
 560 /* retrieves the serialNumber of the given CertId or NULL on error */
 561 ASN1_INTEGER *OSSL_CRMF_CERTID_get0_serialNumber(const OSSL_CRMF_CERTID *cid)
 562 {
 563     return cid != NULL ? cid->serialNumber : NULL;
 564 }
 565
 566 /*-
 567  * fill in certificate template.
 568  * Any value argument that is NULL will leave the respective field unchanged.
 569  */
 570 int OSSL_CRMF_CERTTEMPLATE_fill(OSSL_CRMF_CERTTEMPLATE *tmpl,
 571                                 EVP_PKEY *pubkey,
 572                                 const X509_NAME *subject,
 573                                 const X509_NAME *issuer,
 574                                 const ASN1_INTEGER *serial)
 575 {
 576     if (tmpl == NULL) {
 577         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 578         return 0;
 579     }
 580     if (subject != NULL && !X509_NAME_set((X509_NAME **)&tmpl->subject, subject))
 581         return 0;
 582     if (issuer != NULL && !X509_NAME_set((X509_NAME **)&tmpl->issuer, issuer))
 583         return 0;
 584     if (serial != NULL) {
 585         ASN1_INTEGER_free(tmpl->serialNumber);
 586         if ((tmpl->serialNumber = ASN1_INTEGER_dup(serial)) == NULL)
 587             return 0;
 588     }
 589     if (pubkey != NULL && !X509_PUBKEY_set(&tmpl->publicKey, pubkey))
 590         return 0;
 591     return 1;
 592 }
 593
 594
 595 /*-
 596  * Decrypts the certificate in the given encryptedValue using private key pkey.
 597  * This is needed for the indirect PoP method as in RFC 4210 section 5.2.8.2.
 598  *
 599  * returns a pointer to the decrypted certificate
 600  * returns NULL on error or if no certificate available
 601  */
 602 X509
 603 *OSSL_CRMF_ENCRYPTEDVALUE_get1_encCert(const OSSL_CRMF_ENCRYPTEDVALUE *ecert,
 604                                        OSSL_LIB_CTX *libctx, const char *propq,
 605                                        EVP_PKEY *pkey)
 606 {
 607     X509 *cert = NULL; /* decrypted certificate */
 608     EVP_CIPHER_CTX *evp_ctx = NULL; /* context for symmetric encryption */
 609     unsigned char *ek = NULL; /* decrypted symmetric encryption key */
 610     size_t eksize = 0; /* size of decrypted symmetric encryption key */
 611     EVP_CIPHER *cipher = NULL; /* used cipher */
 612     int cikeysize = 0; /* key size from cipher */
 613     unsigned char *iv = NULL; /* initial vector for symmetric encryption */
 614     unsigned char *outbuf = NULL; /* decryption output buffer */
 615     const unsigned char *p = NULL; /* needed for decoding ASN1 */
 616     int n, outlen = 0;
 617     EVP_PKEY_CTX *pkctx = NULL; /* private key context */
 618     char name[OSSL_MAX_NAME_SIZE];
 619
 620     if (ecert == NULL || ecert->symmAlg == NULL || ecert->encSymmKey == NULL
 621             || ecert->encValue == NULL || pkey == NULL) {
 622         ERR_raise(ERR_LIB_CRMF, CRMF_R_NULL_ARGUMENT);
 623         return NULL;
 624     }
 625
 626     /* select symmetric cipher based on algorithm given in message */
 627     OBJ_obj2txt(name, sizeof(name), ecert->symmAlg->algorithm, 0);
 628
 629     (void)ERR_set_mark();
 630     cipher = EVP_CIPHER_fetch(NULL, name, NULL);
 631
 632     if (cipher == NULL)
 633         cipher = (EVP_CIPHER *)EVP_get_cipherbyname(name);
 634
 635     if (cipher == NULL) {
 636         (void)ERR_clear_last_mark();
 637         ERR_raise(ERR_LIB_CRMF, CRMF_R_UNSUPPORTED_CIPHER);
 638         goto end;
 639     }
 640     (void)ERR_pop_to_mark();
 641
 642     cikeysize = EVP_CIPHER_get_key_length(cipher);
 643     /* first the symmetric key needs to be decrypted */
 644     pkctx = EVP_PKEY_CTX_new_from_pkey(libctx, pkey, propq);
 645     if (pkctx != NULL && EVP_PKEY_decrypt_init(pkctx)) {
 646         ASN1_BIT_STRING *encKey = ecert->encSymmKey;
 647         size_t failure;
 648         int retval;
 649
 650         if (EVP_PKEY_decrypt(pkctx, NULL, &eksize,
 651                              encKey->data, encKey->length) <= 0
 652                 || (ek = OPENSSL_malloc(eksize)) == NULL)
 653             goto end;
 654         retval = EVP_PKEY_decrypt(pkctx, ek, &eksize,
 655                                   encKey->data, encKey->length);
 656         ERR_clear_error(); /* error state may have sensitive information */
 657         failure = ~constant_time_is_zero_s(constant_time_msb(retval)
 658                                            | constant_time_is_zero(retval));
 659         failure |= ~constant_time_eq_s(eksize, (size_t)cikeysize);
 660         if (failure) {
 661             ERR_raise(ERR_LIB_CRMF, CRMF_R_ERROR_DECRYPTING_SYMMETRIC_KEY);
 662             goto end;
 663         }
 664     } else {
 665         goto end;
 666     }
 667     if ((iv = OPENSSL_malloc(EVP_CIPHER_get_iv_length(cipher))) == NULL)
 668         goto end;
 669     if (ASN1_TYPE_get_octetstring(ecert->symmAlg->parameter, iv,
 670                                   EVP_CIPHER_get_iv_length(cipher))
 671         != EVP_CIPHER_get_iv_length(cipher)) {
 672         ERR_raise(ERR_LIB_CRMF, CRMF_R_MALFORMED_IV);
 673         goto end;
 674     }
 675
 676     /*
 677      * d2i_X509 changes the given pointer, so use p for decoding the message and
 678      * keep the original pointer in outbuf so the memory can be freed later
 679      */
 680     if ((p = outbuf = OPENSSL_malloc(ecert->encValue->length +
 681                                      EVP_CIPHER_get_block_size(cipher))) == NULL
 682             || (evp_ctx = EVP_CIPHER_CTX_new()) == NULL)
 683         goto end;
 684     EVP_CIPHER_CTX_set_padding(evp_ctx, 0);
 685
 686     if (!EVP_DecryptInit(evp_ctx, cipher, ek, iv)
 687             || !EVP_DecryptUpdate(evp_ctx, outbuf, &outlen,
 688                                   ecert->encValue->data,
 689                                   ecert->encValue->length)
 690             || !EVP_DecryptFinal(evp_ctx, outbuf + outlen, &n)) {
 691         ERR_raise(ERR_LIB_CRMF, CRMF_R_ERROR_DECRYPTING_CERTIFICATE);
 692         goto end;
 693     }
 694     outlen += n;
 695
 696     /* convert decrypted certificate from DER to internal ASN.1 structure */
 697     if ((cert = X509_new_ex(libctx, propq)) == NULL)
 698         goto end;
 699     if (d2i_X509(&cert, &p, outlen) == NULL)
 700         ERR_raise(ERR_LIB_CRMF, CRMF_R_ERROR_DECODING_CERTIFICATE);
 701  end:
 702     EVP_PKEY_CTX_free(pkctx);
 703     OPENSSL_free(outbuf);
 704     EVP_CIPHER_CTX_free(evp_ctx);
 705     EVP_CIPHER_free(cipher);
 706     OPENSSL_clear_free(ek, eksize);
 707     OPENSSL_free(iv);
 708     return cert;
 709 }