Security/libsecurity_smime/lib/cmspubkey.c

   1 /*
   2  * The contents of this file are subject to the Mozilla Public
   3  * License Version 1.1 (the "License"); you may not use this file
   4  * except in compliance with the License. You may obtain a copy of
   5  * the License at http://www.mozilla.org/MPL/
   6  *
   7  * Software distributed under the License is distributed on an "AS
   8  * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
   9  * implied. See the License for the specific language governing
  10  * rights and limitations under the License.
  11  *
  12  * The Original Code is the Netscape security libraries.
  13  *
  14  * The Initial Developer of the Original Code is Netscape
  15  * Communications Corporation.  Portions created by Netscape are
  16  * Copyright (C) 1994-2000 Netscape Communications Corporation.  All
  17  * Rights Reserved.
  18  *
  19  * Contributor(s):
  20  *
  21  * Alternatively, the contents of this file may be used under the
  22  * terms of the GNU General Public License Version 2 or later (the
  23  * "GPL"), in which case the provisions of the GPL are applicable
  24  * instead of those above.  If you wish to allow use of your
  25  * version of this file only under the terms of the GPL and not to
  26  * allow others to use your version of this file under the MPL,
  27  * indicate your decision by deleting the provisions above and
  28  * replace them with the notice and other provisions required by
  29  * the GPL.  If you do not delete the provisions above, a recipient
  30  * may use your version of this file under either the MPL or the
  31  * GPL.
  32  */
  33
  34 /*
  35  * CMS public key crypto
  36  */
  37
  38 #include "cmslocal.h"
  39
  40 #include "secitem.h"
  41 #include "secoid.h"
  42 #include "cryptohi.h"
  43
  44 #include <security_asn1/secasn1.h>
  45 #include <security_asn1/secerr.h>
  46 #include <Security/SecCertificatePriv.h>
  47 #include <Security/SecKeyPriv.h>
  48 #include <Security/Security.h>
  49 #include <CoreServices/../Frameworks/CarbonCore.framework/Headers/MacErrors.h>
  50 #include <Security/SecCmsBase.h>
  51 #include <Security/secasn1t.h>
  52 #include <security_asn1/plarenas.h>
  53 #include <Security/keyTemplates.h>
  54
  55 /* ====== RSA ======================================================================= */
  56
  57 /*
  58  * SecCmsUtilEncryptSymKeyRSA - wrap a symmetric key with RSA
  59  *
  60  * this function takes a symmetric key and encrypts it using an RSA public key
  61  * according to PKCS#1 and RFC2633 (S/MIME)
  62  */
  63 OSStatus
  64 SecCmsUtilEncryptSymKeyRSA(PLArenaPool *poolp, SecCertificateRef cert,
  65                               SecSymmetricKeyRef bulkkey,
  66                               CSSM_DATA_PTR encKey)
  67 {
  68     OSStatus rv;
  69     SecPublicKeyRef publickey;
  70
  71     rv = SecCertificateCopyPublicKey(cert,&publickey);
  72     if (publickey == NULL)
  73         return SECFailure;
  74
  75     rv = SecCmsUtilEncryptSymKeyRSAPubKey(poolp, publickey, bulkkey, encKey);
  76     CFRelease(publickey);
  77     return rv;
  78 }
  79
  80 OSStatus
  81 SecCmsUtilEncryptSymKeyRSAPubKey(PLArenaPool *poolp,
  82                                  SecPublicKeyRef publickey,
  83                                  SecSymmetricKeyRef bulkkey, CSSM_DATA_PTR encKey)
  84 {
  85     OSStatus rv;
  86     unsigned int data_len;
  87     //KeyType keyType;
  88     void *mark = NULL;
  89
  90     mark = PORT_ArenaMark(poolp);
  91     if (!mark)
  92         goto loser;
  93
  94 #if 0
  95     /* sanity check */
  96     keyType = SECKEY_GetPublicKeyType(publickey);
  97     PORT_Assert(keyType == rsaKey);
  98     if (keyType != rsaKey) {
  99         goto loser;
 100     }
 101 #endif
 102     /* allocate memory for the encrypted key */
 103     rv = SecKeyGetStrengthInBits(publickey, NULL, &data_len);
 104     if (rv)
 105         goto loser;
 106
 107     // Convert length to bytes;
 108     data_len >>= 2;
 109     encKey->Data = (unsigned char*)PORT_ArenaAlloc(poolp, data_len);
 110     encKey->Length = data_len;
 111     if (encKey->Data == NULL)
 112         goto loser;
 113
 114     /* encrypt the key now */
 115     rv = WRAP_PubWrapSymKey(publickey, bulkkey, encKey);
 116     if (rv != SECSuccess)
 117         goto loser;
 118
 119     PORT_ArenaUnmark(poolp, mark);
 120     return SECSuccess;
 121
 122 loser:
 123     if (mark) {
 124         PORT_ArenaRelease(poolp, mark);
 125     }
 126     return SECFailure;
 127 }
 128
 129 /*
 130  * SecCmsUtilDecryptSymKeyRSA - unwrap a RSA-wrapped symmetric key
 131  *
 132  * this function takes an RSA-wrapped symmetric key and unwraps it, returning a symmetric
 133  * key handle. Please note that the actual unwrapped key data may not be allowed to leave
 134  * a hardware token...
 135  */
 136 SecSymmetricKeyRef
 137 SecCmsUtilDecryptSymKeyRSA(SecPrivateKeyRef privkey, CSSM_DATA_PTR encKey, SECOidTag bulkalgtag)
 138 {
 139     /* that's easy */
 140     return WRAP_PubUnwrapSymKey(privkey, encKey, bulkalgtag);
 141 }
 142
 143 #if 0
 144 // @@@ Implement Fortezza and Diffie hellman support
 145
 146 /* ====== MISSI (Fortezza) ========================================================== */
 147
 148 extern const SecAsn1Template NSS_SMIMEKEAParamTemplateAllParams[];
 149
 150 OSStatus
 151 SecCmsUtilEncryptSymKeyMISSI(PLArenaPool *poolp, SecCertificateRef cert, SecSymmetricKeyRef bulkkey,
 152                         SECOidTag symalgtag, CSSM_DATA_PTR encKey, CSSM_DATA_PTR *pparams, void *pwfn_arg)
 153 {
 154     SECOidTag certalgtag;       /* the certificate's encryption algorithm */
 155     SECOidTag encalgtag;        /* the algorithm used for key exchange/agreement */
 156     OSStatus rv = SECFailure;
 157     CSSM_DATA_PTR params = NULL;
 158     OSStatus err;
 159     SecSymmetricKeyRef tek;
 160     SecCertificateRef ourCert;
 161     SecPublicKeyRef ourPubKey, *publickey = NULL;
 162     SecPrivateKeyRef ourPrivKey = NULL;
 163     SecCmsKEATemplateSelector whichKEA = SecCmsKEAInvalid;
 164     SecCmsSMIMEKEAParameters keaParams;
 165     PLArenaPool *arena = NULL;
 166     extern const SecAsn1Template *nss_cms_get_kea_template(SecCmsKEATemplateSelector whichTemplate);
 167     const SECAlgorithmID *algid;
 168
 169     /* Clear keaParams, since cleanup code checks the lengths */
 170     (void) memset(&keaParams, 0, sizeof(keaParams));
 171
 172     SecCertificateGetAlgorithmID(cert,&algid);
 173     certalgtag = SECOID_GetAlgorithmTag(algid);
 174     PORT_Assert(certalgtag == SEC_OID_MISSI_KEA_DSS_OLD ||
 175                 certalgtag == SEC_OID_MISSI_KEA_DSS ||
 176                 certalgtag == SEC_OID_MISSI_KEA);
 177
 178 #define SMIME_FORTEZZA_RA_LENGTH 128
 179 #define SMIME_FORTEZZA_IV_LENGTH 24
 180 #define SMIME_FORTEZZA_MAX_KEY_SIZE 256
 181
 182     /* We really want to show our KEA tag as the key exchange algorithm tag. */
 183     encalgtag = SEC_OID_NETSCAPE_SMIME_KEA;
 184
 185     /* Get the public key of the recipient. */
 186     publickey = CERT_ExtractPublicKey(cert);
 187     if (publickey == NULL) goto loser;
 188
 189     /* Find our own cert, and extract its keys. */
 190     ourCert = PK11_FindBestKEAMatch(cert, pwfn_arg);
 191     if (ourCert == NULL) goto loser;
 192
 193     arena = PORT_NewArena(1024);
 194     if (arena == NULL)
 195         goto loser;
 196
 197     ourPubKey = CERT_ExtractPublicKey(ourCert);
 198     if (ourPubKey == NULL) {
 199         CERT_DestroyCertificate(ourCert);
 200         goto loser;
 201     }
 202
 203     /* While we're here, copy the public key into the outgoing
 204      * KEA parameters. */
 205     SECITEM_CopyItem(arena, &(keaParams.originatorKEAKey), &(ourPubKey->u.fortezza.KEAKey));
 206     SECKEY_DestroyPublicKey(ourPubKey);
 207     ourPubKey = NULL;
 208
 209     /* Extract our private key in order to derive the KEA key. */
 210     ourPrivKey = PK11_FindKeyByAnyCert(ourCert, pwfn_arg);
 211     CERT_DestroyCertificate(ourCert); /* we're done with this */
 212     if (!ourPrivKey)
 213         goto loser;
 214
 215     /* Prepare raItem with 128 bytes (filled with zeros). */
 216     keaParams.originatorRA.Data = (unsigned char *)PORT_ArenaAlloc(arena,SMIME_FORTEZZA_RA_LENGTH);
 217     keaParams.originatorRA.Length = SMIME_FORTEZZA_RA_LENGTH;
 218
 219     /* Generate the TEK (token exchange key) which we use
 220      * to wrap the bulk encryption key. (keaparams.originatorRA) will be
 221      * filled with a random seed which we need to send to
 222      * the recipient. (user keying material in RFC2630/DSA speak) */
 223     tek = PK11_PubDerive(ourPrivKey, publickey, PR_TRUE,
 224                          &keaParams.originatorRA, NULL,
 225                          CKM_KEA_KEY_DERIVE, CKM_SKIPJACK_WRAP,
 226                          CKA_WRAP, 0,  pwfn_arg);
 227
 228     SECKEY_DestroyPublicKey(publickey);
 229     SECKEY_DestroyPrivateKey(ourPrivKey);
 230     publickey = NULL;
 231     ourPrivKey = NULL;
 232
 233     if (!tek)
 234         goto loser;
 235
 236     /* allocate space for the wrapped key data */
 237     encKey->Data = (unsigned char *)PORT_ArenaAlloc(poolp, SMIME_FORTEZZA_MAX_KEY_SIZE);
 238     encKey->Length = SMIME_FORTEZZA_MAX_KEY_SIZE;
 239
 240     if (encKey->Data == NULL) {
 241         CFRelease(tek);
 242         goto loser;
 243     }
 244
 245     /* Wrap the bulk key. What we do with the resulting data
 246        depends on whether we're using Skipjack to wrap the key. */
 247     switch (PK11_AlgtagToMechanism(symalgtag)) {
 248     case CKM_SKIPJACK_CBC64:
 249     case CKM_SKIPJACK_ECB64:
 250     case CKM_SKIPJACK_OFB64:
 251     case CKM_SKIPJACK_CFB64:
 252     case CKM_SKIPJACK_CFB32:
 253     case CKM_SKIPJACK_CFB16:
 254     case CKM_SKIPJACK_CFB8:
 255         /* SKIPJACK, we use the wrap mechanism because we can do it on the hardware */
 256         err = PK11_WrapSymKey(CKM_SKIPJACK_WRAP, NULL, tek, bulkkey, encKey);
 257         whichKEA = SecCmsKEAUsesSkipjack;
 258         break;
 259     default:
 260         /* Not SKIPJACK, we encrypt the raw key data */
 261         keaParams.nonSkipjackIV.Data =
 262           (unsigned char *)PORT_ArenaAlloc(arena, SMIME_FORTEZZA_IV_LENGTH);
 263         keaParams.nonSkipjackIV.Length = SMIME_FORTEZZA_IV_LENGTH;
 264         err = PK11_WrapSymKey(CKM_SKIPJACK_CBC64, &keaParams.nonSkipjackIV, tek, bulkkey, encKey);
 265         if (err != SECSuccess)
 266             goto loser;
 267
 268         if (encKey->Length != PK11_GetKeyLength(bulkkey)) {
 269             /* The size of the encrypted key is not the same as
 270                that of the original bulk key, presumably due to
 271                padding. Encode and store the real size of the
 272                bulk key. */
 273             if (SEC_ASN1EncodeInteger(arena, &keaParams.bulkKeySize, PK11_GetKeyLength(bulkkey)) == NULL)
 274                 err = (OSStatus)PORT_GetError();
 275             else
 276                 /* use full template for encoding */
 277                 whichKEA = SecCmsKEAUsesNonSkipjackWithPaddedEncKey;
 278         }
 279         else
 280             /* enc key length == bulk key length */
 281             whichKEA = SecCmsKEAUsesNonSkipjack;
 282         break;
 283     }
 284
 285     CFRelease(tek);
 286
 287     if (err != SECSuccess)
 288         goto loser;
 289
 290     PORT_Assert(whichKEA != SecCmsKEAInvalid);
 291
 292     /* Encode the KEA parameters into the recipient info. */
 293     params = SEC_ASN1EncodeItem(poolp, NULL, &keaParams, nss_cms_get_kea_template(whichKEA));
 294     if (params == NULL)
 295         goto loser;
 296
 297     /* pass back the algorithm params */
 298     *pparams = params;
 299
 300     rv = SECSuccess;
 301
 302 loser:
 303     if (arena)
 304         PORT_FreeArena(arena, PR_FALSE);
 305     if (publickey)
 306         SECKEY_DestroyPublicKey(publickey);
 307     if (ourPrivKey)
 308         SECKEY_DestroyPrivateKey(ourPrivKey);
 309     return rv;
 310 }
 311
 312 SecSymmetricKeyRef
 313 SecCmsUtilDecryptSymKeyMISSI(SecPrivateKeyRef privkey, CSSM_DATA_PTR encKey, SECAlgorithmID *keyEncAlg, SECOidTag bulkalgtag, void *pwfn_arg)
 314 {
 315     /* fortezza: do a key exchange */
 316     OSStatus err;
 317     CK_MECHANISM_TYPE bulkType;
 318     SecSymmetricKeyRef tek;
 319     SecPublicKeyRef originatorPubKey;
 320     SecCmsSMIMEKEAParameters keaParams;
 321     SecSymmetricKeyRef bulkkey;
 322     int bulkLength;
 323
 324     (void) memset(&keaParams, 0, sizeof(keaParams));
 325
 326     /* NOTE: this uses the SMIME v2 recipientinfo for compatibility.
 327        All additional KEA parameters are DER-encoded in the encryption algorithm parameters */
 328
 329     /* Decode the KEA algorithm parameters. */
 330     err = SEC_ASN1DecodeItem(NULL, &keaParams, NSS_SMIMEKEAParamTemplateAllParams,
 331                              &(keyEncAlg->parameters));
 332     if (err != SECSuccess)
 333         goto loser;
 334
 335     /* get originator's public key */
 336    originatorPubKey = PK11_MakeKEAPubKey(keaParams.originatorKEAKey.Data,
 337                            keaParams.originatorKEAKey.Length);
 338    if (originatorPubKey == NULL)
 339           goto loser;
 340
 341    /* Generate the TEK (token exchange key) which we use to unwrap the bulk encryption key.
 342       The Derive function generates a shared secret and combines it with the originatorRA
 343       data to come up with an unique session key */
 344    tek = PK11_PubDerive(privkey, originatorPubKey, PR_FALSE,
 345                          &keaParams.originatorRA, NULL,
 346                          CKM_KEA_KEY_DERIVE, CKM_SKIPJACK_WRAP,
 347                          CKA_WRAP, 0, pwfn_arg);
 348    SECKEY_DestroyPublicKey(originatorPubKey);   /* not needed anymore */
 349    if (tek == NULL)
 350         goto loser;
 351
 352     /* Now that we have the TEK, unwrap the bulk key
 353        with which to decrypt the message. We have to
 354        do one of two different things depending on
 355        whether Skipjack was used for *bulk* encryption
 356        of the message. */
 357     bulkType = PK11_AlgtagToMechanism(bulkalgtag);
 358     switch (bulkType) {
 359     case CKM_SKIPJACK_CBC64:
 360     case CKM_SKIPJACK_ECB64:
 361     case CKM_SKIPJACK_OFB64:
 362     case CKM_SKIPJACK_CFB64:
 363     case CKM_SKIPJACK_CFB32:
 364     case CKM_SKIPJACK_CFB16:
 365     case CKM_SKIPJACK_CFB8:
 366         /* Skipjack is being used as the bulk encryption algorithm.*/
 367         /* Unwrap the bulk key. */
 368         bulkkey = PK11_UnwrapSymKey(tek, CKM_SKIPJACK_WRAP, NULL,
 369                                     encKey, CKM_SKIPJACK_CBC64, CKA_DECRYPT, 0);
 370         break;
 371     default:
 372         /* Skipjack was not used for bulk encryption of this
 373            message. Use Skipjack CBC64, with the nonSkipjackIV
 374            part of the KEA key parameters, to decrypt
 375            the bulk key. If the optional parameter bulkKeySize is present,
 376            bulk key size is different than the encrypted key size */
 377         if (keaParams.bulkKeySize.Length > 0) {
 378             err = SEC_ASN1DecodeItem(NULL, &bulkLength,
 379                                      SEC_ASN1_GET(SEC_IntegerTemplate),
 380                                      &keaParams.bulkKeySize);
 381             if (err != SECSuccess)
 382                 goto loser;
 383         }
 384
 385         bulkkey = PK11_UnwrapSymKey(tek, CKM_SKIPJACK_CBC64, &keaParams.nonSkipjackIV,
 386                                     encKey, bulkType, CKA_DECRYPT, bulkLength);
 387         break;
 388     }
 389     return bulkkey;
 390 loser:
 391     return NULL;
 392 }
 393
 394 /* ====== ESDH (Ephemeral-Static Diffie-Hellman) ==================================== */
 395
 396 OSStatus
 397 SecCmsUtilEncryptSymKeyESDH(PLArenaPool *poolp, SecCertificateRef cert, SecSymmetricKeyRef key,
 398                         CSSM_DATA_PTR encKey, CSSM_DATA_PTR ukm, SECAlgorithmID *keyEncAlg,
 399                         CSSM_DATA_PTR pubKey)
 400 {
 401 #if 0 /* not yet done */
 402     SECOidTag certalgtag;       /* the certificate's encryption algorithm */
 403     SECOidTag encalgtag;        /* the algorithm used for key exchange/agreement */
 404     OSStatus rv;
 405     CSSM_DATA_PTR params = NULL;
 406     int data_len;
 407     OSStatus err;
 408     SecSymmetricKeyRef tek;
 409     SecCertificateRef ourCert;
 410     SecPublicKeyRef ourPubKey;
 411     SecCmsKEATemplateSelector whichKEA = SecCmsKEAInvalid;
 412
 413     certalgtag = SECOID_GetAlgorithmTag(&(cert->subjectPublicKeyInfo.algorithm));
 414     PORT_Assert(certalgtag == SEC_OID_X942_DIFFIE_HELMAN_KEY);
 415
 416     /* We really want to show our KEA tag as the key exchange algorithm tag. */
 417     encalgtag = SEC_OID_CMS_EPHEMERAL_STATIC_DIFFIE_HELLMAN;
 418
 419     /* Get the public key of the recipient. */
 420     publickey = CERT_ExtractPublicKey(cert);
 421     if (publickey == NULL) goto loser;
 422
 423     /* XXXX generate a DH key pair on a PKCS11 module (XXX which parameters?) */
 424     /* XXXX */ourCert = PK11_FindBestKEAMatch(cert, wincx);
 425     if (ourCert == NULL) goto loser;
 426
 427     arena = PORT_NewArena(1024);
 428     if (arena == NULL) goto loser;
 429
 430     /* While we're here, extract the key pair's public key data and copy it into */
 431     /* the outgoing parameters. */
 432     /* XXXX */ourPubKey = CERT_ExtractPublicKey(ourCert);
 433     if (ourPubKey == NULL)
 434     {
 435         goto loser;
 436     }
 437     SECITEM_CopyItem(arena, pubKey, /* XXX */&(ourPubKey->u.fortezza.KEAKey));
 438     SECKEY_DestroyPublicKey(ourPubKey); /* we only need the private key from now on */
 439     ourPubKey = NULL;
 440
 441     /* Extract our private key in order to derive the KEA key. */
 442     ourPrivKey = PK11_FindKeyByAnyCert(ourCert,wincx);
 443     CERT_DestroyCertificate(ourCert); /* we're done with this */
 444     if (!ourPrivKey) goto loser;
 445
 446     /* If ukm desired, prepare it - allocate enough space (filled with zeros). */
 447     if (ukm) {
 448         ukm->Data = (unsigned char*)PORT_ArenaZAlloc(arena,/* XXXX */);
 449         ukm->Length = /* XXXX */;
 450     }
 451
 452     /* Generate the KEK (key exchange key) according to RFC2631 which we use
 453      * to wrap the bulk encryption key. */
 454     kek = PK11_PubDerive(ourPrivKey, publickey, PR_TRUE,
 455                          ukm, NULL,
 456                          /* XXXX */CKM_KEA_KEY_DERIVE, /* XXXX */CKM_SKIPJACK_WRAP,
 457                          CKA_WRAP, 0, wincx);
 458
 459     SECKEY_DestroyPublicKey(publickey);
 460     SECKEY_DestroyPrivateKey(ourPrivKey);
 461     publickey = NULL;
 462     ourPrivKey = NULL;
 463
 464     if (!kek)
 465         goto loser;
 466
 467     /* allocate space for the encrypted CEK (bulk key) */
 468     encKey->Data = (unsigned char*)PORT_ArenaAlloc(poolp, SMIME_FORTEZZA_MAX_KEY_SIZE);
 469     encKey->Length = SMIME_FORTEZZA_MAX_KEY_SIZE;
 470
 471     if (encKey->Data == NULL)
 472     {
 473         CFRelease(kek);
 474         goto loser;
 475     }
 476
 477
 478     /* Wrap the bulk key using CMSRC2WRAP or CMS3DESWRAP, depending on the */
 479     /* bulk encryption algorithm */
 480     switch (/* XXXX */PK11_AlgtagToMechanism(enccinfo->encalg))
 481     {
 482     case /* XXXX */CKM_SKIPJACK_CFB8:
 483         err = PK11_WrapSymKey(/* XXXX */CKM_CMS3DES_WRAP, NULL, kek, bulkkey, encKey);
 484         whichKEA = SecCmsKEAUsesSkipjack;
 485         break;
 486     case /* XXXX */CKM_SKIPJACK_CFB8:
 487         err = PK11_WrapSymKey(/* XXXX */CKM_CMSRC2_WRAP, NULL, kek, bulkkey, encKey);
 488         whichKEA = SecCmsKEAUsesSkipjack;
 489         break;
 490     default:
 491         /* XXXX what do we do here? Neither RC2 nor 3DES... */
 492         err = SECFailure;
 493         /* set error */
 494         break;
 495     }
 496
 497     CFRelease(kek);     /* we do not need the KEK anymore */
 498     if (err != SECSuccess)
 499         goto loser;
 500
 501     PORT_Assert(whichKEA != SecCmsKEAInvalid);
 502
 503     /* see RFC2630 12.3.1.1 "keyEncryptionAlgorithm must be ..." */
 504     /* params is the DER encoded key wrap algorithm (with parameters!) (XXX) */
 505     params = SEC_ASN1EncodeItem(arena, NULL, &keaParams, sec_pkcs7_get_kea_template(whichKEA));
 506     if (params == NULL)
 507         goto loser;
 508
 509     /* now set keyEncAlg */
 510     rv = SECOID_SetAlgorithmID(poolp, keyEncAlg, SEC_OID_CMS_EPHEMERAL_STATIC_DIFFIE_HELLMAN, params);
 511     if (rv != SECSuccess)
 512         goto loser;
 513
 514     /* XXXXXXX this is not right yet */
 515 loser:
 516     if (arena) {
 517         PORT_FreeArena(arena, PR_FALSE);
 518     }
 519     if (publickey) {
 520         SECKEY_DestroyPublicKey(publickey);
 521     }
 522     if (ourPrivKey) {
 523         SECKEY_DestroyPrivateKey(ourPrivKey);
 524     }
 525 #endif
 526     return SECFailure;
 527 }
 528
 529 SecSymmetricKeyRef
 530 SecCmsUtilDecryptSymKeyESDH(SecPrivateKeyRef privkey, CSSM_DATA_PTR encKey, SECAlgorithmID *keyEncAlg, SECOidTag bulkalgtag, void *pwfn_arg)
 531 {
 532 #if 0 /* not yet done */
 533     OSStatus err;
 534     CK_MECHANISM_TYPE bulkType;
 535     SecSymmetricKeyRef tek;
 536     SecPublicKeyRef originatorPubKey;
 537     SecCmsSMIMEKEAParameters keaParams;
 538
 539    /* XXXX get originator's public key */
 540    originatorPubKey = PK11_MakeKEAPubKey(keaParams.originatorKEAKey.Data,
 541                            keaParams.originatorKEAKey.Length);
 542    if (originatorPubKey == NULL)
 543       goto loser;
 544
 545    /* Generate the TEK (token exchange key) which we use to unwrap the bulk encryption key.
 546       The Derive function generates a shared secret and combines it with the originatorRA
 547       data to come up with an unique session key */
 548    tek = PK11_PubDerive(privkey, originatorPubKey, PR_FALSE,
 549                          &keaParams.originatorRA, NULL,
 550                          CKM_KEA_KEY_DERIVE, CKM_SKIPJACK_WRAP,
 551                          CKA_WRAP, 0, pwfn_arg);
 552    SECKEY_DestroyPublicKey(originatorPubKey);   /* not needed anymore */
 553    if (tek == NULL)
 554         goto loser;
 555
 556     /* Now that we have the TEK, unwrap the bulk key
 557        with which to decrypt the message. */
 558     /* Skipjack is being used as the bulk encryption algorithm.*/
 559     /* Unwrap the bulk key. */
 560     bulkkey = PK11_UnwrapSymKey(tek, CKM_SKIPJACK_WRAP, NULL,
 561                                 encKey, CKM_SKIPJACK_CBC64, CKA_DECRYPT, 0);
 562
 563     return bulkkey;
 564
 565 loser:
 566 #endif
 567     return NULL;
 568 }
 569
 570 #endif  /* Fortezza, DIffie-Hellman */
 571
 572 #define CFRELEASE(cf)   if(cf != NULL) { CFRelease(cf); }
 573
 574 /* ====== ECDH (Ephemeral-Static Diffie-Hellman) ==================================== */
 575
 576 #pragma mark ---- ECDH support functions ----
 577
 578 #ifdef  NDEBUG
 579 #define CSSM_PERROR(f, r)
 580 #define dprintf(args...)
 581 #else
 582 #define CSSM_PERROR(f, r)   cssmPerror(f, r)
 583 #define dprintf(args...)    printf(args)
 584 #endif
 585
 586 /* Length of KeyAgreeRecipientInfo.ukm we create */
 587 #define UKM_LENGTH      8
 588
 589 /* KEK algorithm info we generate */
 590 #define ECDH_KEK_ALG_TAG            SEC_OID_DES_EDE3_CBC
 591 #define ECDH_KEK_KEY_CSSM_ALGID     CSSM_ALGID_3DES_3KEY
 592 #define ECDH_KEK_ENCR_CSSM_ALGID    CSSM_ALGID_3DES_3KEY_EDE
 593 #define ECDH_KEK_KEY_LEN_BYTES      24
 594 #define ECDH_KEK_IV_LEN_BYTES       8
 595
 596 #define CMS_DUMP_BUFS       0
 597 #if     CMS_DUMP_BUFS
 598
 599 static void dumpBuf(
 600     const char *label,
 601     const CSSM_DATA *cd)
 602 {
 603     unsigned dex;
 604
 605     printf("%s:\n   ", label);
 606     for(dex=0; dex<cd->Length; dex++) {
 607         printf("%02X ", cd->Data[dex]);
 608         if(((dex % 16) == 15) && (dex != (cd->Length - 1))) {
 609             printf("\n   ");
 610         }
 611     }
 612     putchar('\n');
 613 }
 614
 615 #else
 616 #define dumpBuf(l, d)
 617 #endif  /* CMS_DUMP_BUFS */
 618
 619 /*
 620  * The ECC-CMS-SharedInfo struct, as defined in RFC 3278 8.2, and the
 621  * template for DER encoding and decoding it.
 622  */
 623 typedef struct {
 624     SECAlgorithmID  algId;          /* KEK alg, NULL params */
 625     CSSM_DATA       entityUInfo;    /* optional, ukm */
 626     CSSM_DATA       suppPubInfo;    /* length of KEK in bits as 4-byte integer */
 627 } ECC_CMS_SharedInfo;
 628
 629 static const SecAsn1Template ECC_CMS_SharedInfoTemplate[] = {
 630     { SEC_ASN1_SEQUENCE, 0, NULL, sizeof(ECC_CMS_SharedInfo) },
 631     { SEC_ASN1_OPTIONAL | SEC_ASN1_CONSTRUCTED | SEC_ASN1_EXPLICIT | SEC_ASN1_CONTEXT_SPECIFIC | 0,
 632           offsetof(ECC_CMS_SharedInfo,entityUInfo),
 633           kSecAsn1OctetStringTemplate },
 634     { SEC_ASN1_CONSTRUCTED | SEC_ASN1_EXPLICIT | SEC_ASN1_CONTEXT_SPECIFIC | 2,
 635           offsetof(ECC_CMS_SharedInfo,suppPubInfo),
 636           kSecAsn1OctetStringTemplate },
 637     { 0 }
 638 };
 639
 640 /*
 641  * Given a context specified via a CSSM_CC_HANDLE, add a new
 642  * CSSM_CONTEXT_ATTRIBUTE to the context as specified by AttributeType,
 643  * AttributeLength, and an untyped pointer.
 644  */
 645 /* specify either 32-bit integer or a pointer as an added attribute value */
 646 typedef enum {
 647         CAT_Uint32,
 648         CAT_Ptr
 649 } ContextAttrType;
 650
 651 static CSSM_RETURN cmsAddContextAttribute(
 652     CSSM_CC_HANDLE CCHandle,
 653     uint32 AttributeType,
 654     uint32 AttributeLength,
 655     ContextAttrType attrType,
 656     /* specify exactly one of these */
 657     const void *AttributePtr,
 658     uint32 attributeInt)
 659 {
 660     CSSM_CONTEXT_ATTRIBUTE              newAttr;
 661     CSSM_RETURN                                 crtn;
 662
 663     newAttr.AttributeType     = AttributeType;
 664     newAttr.AttributeLength   = AttributeLength;
 665     if(attrType == CAT_Uint32) {
 666             newAttr.Attribute.Uint32  = attributeInt;
 667     }
 668     else {
 669             /* this is a union of a bunch of different pointers...*/
 670             newAttr.Attribute.Data    = (CSSM_DATA_PTR)AttributePtr;
 671     }
 672     crtn = CSSM_UpdateContextAttributes(CCHandle, 1, &newAttr);
 673     if(crtn) {
 674         CSSM_PERROR("CSSM_UpdateContextAttributes", crtn);
 675     }
 676     return crtn;
 677 }
 678
 679 static CSSM_RETURN cmsGenRand(
 680     CSSM_CSP_HANDLE cspHand,
 681     CSSM_SIZE len,
 682     uint8 *randOut)
 683 {
 684     CSSM_CC_HANDLE ccHand = 0;
 685     CSSM_DATA randData = {len, randOut};
 686
 687     CSSM_RETURN crtn = CSSM_CSP_CreateRandomGenContext(cspHand,
 688             CSSM_ALGID_APPLE_YARROW,
 689             NULL, /* seed*/
 690             len,
 691             &ccHand);
 692     if(crtn) {
 693         CSSM_PERROR("CSSM_CSP_CreateRandomGenContext", crtn);
 694         return crtn;
 695     }
 696     crtn = CSSM_GenerateRandom(ccHand, &randData);
 697     CSSM_DeleteContext(ccHand);
 698     if(crtn) {
 699         CSSM_PERROR("CSSM_GenerateRandom", crtn);
 700     }
 701     return crtn;
 702 }
 703
 704 /* convert uint32 to big-endian 4 bytes */
 705 static void int32ToBytes(
 706         uint32_t i,
 707         unsigned char *b)
 708 {
 709     int dex;
 710     for(dex=3; dex>=0; dex--) {
 711             b[dex] = i;
 712             i >>= 8;
 713     }
 714 }
 715
 716 /*
 717  * NULL wrap a ref key to raw key in default format.
 718  */
 719 static OSStatus cmsNullWrapKey(
 720     CSSM_CSP_HANDLE cspHand,
 721     const CSSM_KEY *refKey,
 722     CSSM_KEY_PTR rawKey)
 723 {
 724     CSSM_DATA descData = {0, 0};
 725     CSSM_RETURN crtn;
 726     CSSM_CC_HANDLE ccHand;
 727     CSSM_ACCESS_CREDENTIALS creds;
 728     uint32 keyAttr;
 729
 730     memset(&creds, 0, sizeof(CSSM_ACCESS_CREDENTIALS));
 731     memset(rawKey, 0, sizeof(CSSM_KEY));
 732
 733     crtn = CSSM_CSP_CreateSymmetricContext(cspHand,
 734                     CSSM_ALGID_NONE,
 735                     CSSM_ALGMODE_NONE,
 736                     &creds,
 737                     NULL,                       // unwrappingKey
 738                     NULL,                       // initVector
 739                     CSSM_PADDING_NONE,
 740                     0,                          // Params
 741                     &ccHand);
 742     if(crtn) {
 743         CSSM_PERROR("CSSM_CSP_CreateSymmetricContext", crtn);
 744         return crtn;
 745     }
 746
 747     keyAttr = rawKey->KeyHeader.KeyAttr;
 748     keyAttr &= ~(CSSM_KEYATTR_ALWAYS_SENSITIVE | CSSM_KEYATTR_NEVER_EXTRACTABLE |
 749                              CSSM_KEYATTR_MODIFIABLE);
 750     keyAttr |= CSSM_KEYATTR_RETURN_DATA | CSSM_KEYATTR_EXTRACTABLE;
 751     crtn = CSSM_WrapKey(ccHand,
 752             &creds,
 753             refKey,
 754             &descData,
 755             rawKey);
 756     if(crtn != CSSM_OK) {
 757         CSSM_PERROR("CSSM_WrapKey", crtn);
 758     }
 759     CSSM_DeleteContext(ccHand);
 760     return crtn;
 761 }
 762
 763 /*
 764  * Free memory via specified plugin's app-level allocator
 765  */
 766 static void cmsFreeCssmMemory(
 767     CSSM_HANDLE hand,
 768     void        *p)
 769 {
 770     CSSM_API_MEMORY_FUNCS memFuncs;
 771     CSSM_RETURN crtn = CSSM_GetAPIMemoryFunctions(hand, &memFuncs);
 772     if(crtn) {
 773             return;
 774     }
 775     memFuncs.free_func(p, memFuncs.AllocRef);
 776 }
 777
 778 /*
 779  * Given an OID tag, return key size and mode.
 780  * NOTE: ciphers with variable key sizes, like RC2, RC4, and RC5 cannot
 781  * be used here because the message does not contain a key size
 782  * indication.
 783  */
 784 static OSStatus encrAlgInfo(
 785     SECOidTag           oidTag,
 786     uint32              *keySizeBits,   /* RETURNED */
 787     CSSM_ENCRYPT_MODE   *mode)          /* RETURNED */
 788 {
 789     *keySizeBits = 64;              /* default */
 790     *mode = CSSM_ALGMODE_CBCPadIV8; /* default */
 791
 792     switch(oidTag) {
 793         case SEC_OID_RC2_CBC:
 794         case SEC_OID_RC4:
 795         case SEC_OID_RC5_CBC_PAD:
 796             dprintf("encrAlgInfo: key size unknowable\n");
 797             return errSecDataNotAvailable;
 798
 799         case SEC_OID_DES_EDE3_CBC:
 800             *keySizeBits = 192;
 801             break;
 802         case SEC_OID_DES_EDE:
 803             /* Not sure about this; SecCmsCipherContextStart() treats this
 804              * like SEC_OID_DES_EDE3_CBC... */
 805         case SEC_OID_DES_ECB:
 806             *mode = CSSM_ALGMODE_ECB;
 807             break;
 808         case SEC_OID_DES_CBC:
 809             *mode = CSSM_ALGMODE_CBC;
 810             break;
 811         case SEC_OID_AES_128_CBC:
 812             *keySizeBits = 128;
 813             break;
 814         case SEC_OID_AES_192_CBC:
 815             *keySizeBits = 192;
 816             break;
 817         case SEC_OID_AES_256_CBC:
 818             *keySizeBits = 256;
 819             break;
 820         case SEC_OID_AES_128_ECB:
 821             *keySizeBits = 128;
 822             *mode = CSSM_ALGMODE_ECB;
 823             break;
 824         case SEC_OID_AES_192_ECB:
 825             *keySizeBits = 192;
 826             *mode = CSSM_ALGMODE_ECB;
 827             break;
 828         case SEC_OID_AES_256_ECB:
 829             *keySizeBits = 256;
 830             *mode = CSSM_ALGMODE_ECB;
 831             break;
 832         case SEC_OID_DES_OFB:
 833             *mode = CSSM_ALGMODE_OFB;
 834             break;
 835         case SEC_OID_DES_CFB:
 836             *mode = CSSM_ALGMODE_CFB;
 837             break;
 838         default:
 839             dprintf("encrAlgInfo: unknown alg tag (%d)\n", (int)oidTag);
 840             return errSecDataNotAvailable;
 841     }
 842     return noErr;
 843 }
 844
 845 #pragma mark ---- ECDH CEK key wrap ----
 846
 847 /*
 848  * Encrypt bulk encryption key (a.k.a. content encryption key, CEK) using ECDH
 849  */
 850 OSStatus
 851 SecCmsUtilEncryptSymKeyECDH(
 852     PLArenaPool *poolp,
 853     SecCertificateRef cert,     /* recipient's cert */
 854     SecSymmetricKeyRef key,     /* bulk key */
 855     /* remaining fields RETURNED */
 856     CSSM_DATA_PTR encKey,       /* encrypted key --> recipientEncryptedKeys[0].EncryptedKey */
 857     CSSM_DATA_PTR ukm,          /* random UKM --> KeyAgreeRecipientInfo.ukm */
 858     SECAlgorithmID *keyEncAlg,  /* alg := dhSinglePass-stdDH-sha1kdf-scheme
 859                                  * params := another encoded AlgId, with the KEK alg and IV */
 860     CSSM_DATA_PTR pubKey)       /* our pub key as ECPoint -->
 861                                  * KeyAgreeRecipientInfo.originator.OriginatorPublicKey */
 862 {
 863     OSStatus rv = noErr;
 864     CSSM_KEY ourPrivKeyCssm;
 865     CSSM_KEY ourPubKeyCssm;
 866     SecKeyRef theirPubKeyRef = NULL;
 867     CSSM_KEY_PTR theirPubKeyCssm = NULL;
 868     const CSSM_KEY *cekCssmRef = NULL;
 869     uint32 ecdhKeySizeBits;
 870     CSSM_CSP_HANDLE rawCspHand = SecCspHandleForAlgorithm(CSSM_ALGID_ECDH);
 871     CSSM_CC_HANDLE ccHand = 0;
 872     CSSM_RETURN crtn;
 873     CSSM_DATA keyLabel = {8, (uint8 *)"tempKey"};
 874     SECAlgorithmID kekAlgId;
 875     uint8 iv[ECDH_KEK_IV_LEN_BYTES];
 876     CSSM_DATA ivData = {ECDH_KEK_IV_LEN_BYTES, iv};
 877     SECOidData *kekOid;
 878     ECC_CMS_SharedInfo sharedInfo;
 879     CSSM_DATA sharedInfoEnc = {0, NULL};
 880     uint8 nullData[2] = {SEC_ASN1_NULL, 0};
 881     uint8 keyLenAsBytes[4];
 882     CSSM_KEY kekDerive;
 883     CSSM_DATA certData;
 884     CSSM_CL_HANDLE clHand;
 885     CSSM_ACCESS_CREDENTIALS creds;
 886     CSSM_DATA paramData = {0, NULL};
 887     CSSM_KEY cekCssm;
 888     CSSM_CSP_HANDLE refCspHand;
 889     CSSM_SIZE bytesEncrypted;
 890     CSSM_DATA remData = {0, NULL};
 891     CSSM_DATA ctext = {0, NULL};
 892     CSSM_X509_SUBJECT_PUBLIC_KEY_INFO subjPubKey;
 893
 894     if(rawCspHand == 0) {
 895         return internalComponentErr;
 896     }
 897
 898     memset(&ourPrivKeyCssm, 0, sizeof(CSSM_KEY));
 899     memset(&ourPubKeyCssm, 0, sizeof(CSSM_KEY));
 900     memset(&cekCssm, 0, sizeof(CSSM_KEY));
 901     memset(&kekDerive, 0, sizeof(kekDerive));
 902
 903     encKey->Data = NULL;
 904     encKey->Length = 0;
 905
 906     /*
 907      * Create our ECDH key pair matching the recipient's key.
 908      * Get the public key in "read-only" OCTET_STRING format, which
 909      * is the ECPoint we put in
 910      * KeyAgreeRecipientInfo.originator.OriginatorPublicKey.
 911      */
 912     rv = SecCertificateGetData(cert, &certData);
 913     if(rv) {
 914         CSSM_PERROR("SecCertificateGetData", rv);
 915         return rv;
 916     }
 917     rv = SecCertificateGetCLHandle(cert, &clHand);
 918     if(rv) {
 919         CSSM_PERROR("SecCertificateGetCLHandle", rv);
 920         return rv;
 921     }
 922     rv = CSSM_CL_CertGetKeyInfo(clHand, &certData, &theirPubKeyCssm);
 923      if(rv) {
 924         CSSM_PERROR("CSSM_CL_CertGetKeyInfo", rv);
 925         return rv;
 926     }
 927
 928     /*
 929      * Verify the EC curve of the recipient's public key. It's in the
 930      * public key's AlgId.parameters as an OID. The key we were
 931      * given is in CSSM_X509_SUBJECT_PUBLIC_KEY_INFO form.
 932      */
 933     memset(&subjPubKey, 0, sizeof(subjPubKey));
 934     if(SEC_ASN1DecodeItem(poolp, &subjPubKey, kSecAsn1SubjectPublicKeyInfoTemplate,
 935             &theirPubKeyCssm->KeyData)) {
 936         dprintf("SecCmsUtilEncryptSymKeyECDH: error decoding SubjPubKey\n");
 937         /* oh well, keep going */
 938     }
 939     else {
 940         if(subjPubKey.algorithm.parameters.Data != NULL) {
 941             CSSM_DATA curveOid;
 942             if(SEC_ASN1DecodeItem(poolp, &curveOid, kSecAsn1ObjectIDTemplate,
 943                     &subjPubKey.algorithm.parameters)) {
 944                 dprintf("SecCmsUtilEncryptSymKeyECDH: error decoding curveOid\n");
 945                 /* oh well, keep going */
 946             }
 947             else {
 948                 /* We have the curve OID. Any other errors are fatal. */
 949                 SECOidTag oidTag = SECOID_FindOIDTag(&curveOid);
 950                 switch(oidTag) {
 951                     case SEC_OID_SECP_256_R1:
 952                     case SEC_OID_SECP_384_R1:
 953                     case SEC_OID_SECP_521_R1:
 954                         break;
 955                     default:
 956                         dprintf("SecCmsUtilEncryptSymKeyECDH: unsupported curveOid\n");
 957                         rv = CSSMERR_CSP_INVALID_KEY;
 958                         goto loser;
 959                 }
 960             }
 961         }
 962     }
 963
 964     ecdhKeySizeBits = theirPubKeyCssm->KeyHeader.LogicalKeySizeInBits;
 965     crtn = CSSM_CSP_CreateKeyGenContext(rawCspHand,
 966             CSSM_ALGID_ECDSA,
 967             ecdhKeySizeBits,
 968             NULL,                       // Seed
 969             NULL,                       // Salt
 970             NULL,                       // StartDate
 971             NULL,                       // EndDate
 972             NULL,                       // Params
 973             &ccHand);
 974     if(crtn) {
 975         CSSM_PERROR("CSSM_CSP_CreateKeyGenContext", crtn);
 976         rv = crtn;
 977         goto loser;
 978     }
 979     crtn = cmsAddContextAttribute(ccHand,
 980         CSSM_ATTRIBUTE_PUBLIC_KEY_FORMAT,
 981         sizeof(uint32),
 982         CAT_Uint32,
 983         NULL,
 984         CSSM_KEYBLOB_RAW_FORMAT_OCTET_STRING);
 985     if(crtn) {
 986         CSSM_PERROR("AddContextAttribute(CSSM_ATTRIBUTE_PUBLIC_KEY_FORMAT)", crtn);
 987         rv = crtn;
 988         goto loser;
 989     }
 990
 991     crtn = CSSM_GenerateKeyPair(ccHand,
 992             CSSM_KEYUSE_DERIVE,
 993             CSSM_KEYATTR_RETURN_DATA | CSSM_KEYATTR_EXTRACTABLE,
 994             &keyLabel,
 995             &ourPubKeyCssm,
 996             CSSM_KEYUSE_DERIVE,
 997             CSSM_KEYATTR_RETURN_REF | CSSM_KEYATTR_EXTRACTABLE,
 998             &keyLabel,
 999             NULL,                       // CredAndAclEntry
1000             &ourPrivKeyCssm);
1001     CSSM_DeleteContext(ccHand);
1002     ccHand = 0;
1003     if(crtn) {
1004         CSSM_PERROR("CSSM_GenerateKeyPair", crtn);
1005         rv = crtn;
1006         goto loser;
1007     }
1008     pubKey->Length = ourPubKeyCssm.KeyData.Length;
1009     pubKey->Data = (uint8 *)PORT_ArenaAlloc(poolp, pubKey->Length);
1010     memmove(pubKey->Data, ourPubKeyCssm.KeyData.Data, pubKey->Length);
1011     dumpBuf("sender's public key", pubKey);
1012
1013     /*
1014      * Cook up random UKM
1015      */
1016     ukm->Data = (uint8 *)PORT_ArenaAlloc(poolp, UKM_LENGTH);
1017     ukm->Length = UKM_LENGTH;
1018     crtn = cmsGenRand(rawCspHand, UKM_LENGTH, ukm->Data);
1019     if(crtn) {
1020         goto loser;
1021     }
1022     dumpBuf("sender UKM", ukm);
1023
1024     /*
1025      * OK, we have to set up a weird SECAlgorithmID.
1026      * algorithm = dhSinglePass-stdDH-sha1kdf-scheme
1027      * params = an encoded SECAlgorithmID representing the KEK algorithm, with
1028      *   algorithm = whatever we pick
1029      *   parameters = IV as octet string (though I haven't seen that specified
1030      *                anywhere; it's how the CEK IV is encoded)
1031      *
1032      * First, the 8-byte random IV, encoded as octet string
1033      */
1034     crtn = cmsGenRand(rawCspHand, ECDH_KEK_IV_LEN_BYTES, iv);
1035     if(crtn) {
1036         goto loser;
1037     }
1038     dumpBuf("sender IV", &ivData);
1039
1040     memset(&kekAlgId, 0, sizeof(kekAlgId));
1041     if (!SEC_ASN1EncodeItem(poolp, &kekAlgId.parameters,
1042             &ivData, kSecAsn1OctetStringTemplate)) {
1043         rv = internalComponentErr;
1044         goto loser;
1045     }
1046
1047     /* Drop in the KEK OID and encode the whole thing */
1048     kekOid = SECOID_FindOIDByTag(ECDH_KEK_ALG_TAG);
1049     if(kekOid == NULL) {
1050         dprintf("SecCmsUtilEncryptSymKeyECDH: OID screwup\n");
1051         rv = internalComponentErr;
1052         goto loser;
1053     }
1054     kekAlgId.algorithm = kekOid->oid;
1055     memset(keyEncAlg, 0, sizeof(*keyEncAlg));
1056     if (!SEC_ASN1EncodeItem(poolp, &keyEncAlg->parameters,
1057             &kekAlgId, SECOID_AlgorithmIDTemplate)) {
1058         rv = internalComponentErr;
1059         goto loser;
1060     }
1061     kekOid = SECOID_FindOIDByTag(SEC_OID_DH_SINGLE_STD_SHA1KDF);
1062     if(kekOid == NULL) {
1063         dprintf("SecCmsUtilEncryptSymKeyECDH: OID screwup\n");
1064         rv = internalComponentErr;
1065         goto loser;
1066     }
1067     keyEncAlg->algorithm = kekOid->oid;
1068
1069     /*
1070      * Now in order to derive the KEK proper, we have to create a
1071      * ECC-CMS-SharedInfo, which does not appear in the message, and DER
1072      * encode that struct, the result of which is used as the
1073      * SharedInfo value in the KEK key derive.
1074      */
1075     memset(&sharedInfo, 0, sizeof(sharedInfo));
1076     kekOid = SECOID_FindOIDByTag(ECDH_KEK_ALG_TAG);
1077     sharedInfo.algId.algorithm = kekOid->oid;
1078     sharedInfo.algId.parameters.Data = nullData;
1079     sharedInfo.algId.parameters.Length = 2;
1080     sharedInfo.entityUInfo = *ukm;
1081     int32ToBytes(ECDH_KEK_KEY_LEN_BYTES << 3, keyLenAsBytes);
1082     sharedInfo.suppPubInfo.Length = 4;
1083     sharedInfo.suppPubInfo.Data = keyLenAsBytes;
1084     if (!SEC_ASN1EncodeItem(poolp, &sharedInfoEnc,
1085             &sharedInfo, ECC_CMS_SharedInfoTemplate)) {
1086         rv = internalComponentErr;
1087         goto loser;
1088     }
1089     dumpBuf("sender encoded SharedInfo", &sharedInfoEnc);
1090
1091     /*
1092      * Since we're using the raw CSP here, we can provide the "other" public
1093      * key as an actual CSSM_KEY. When unwrapping, we won't be able to do that
1094      * since we'll be using our private key obtained from a SecIdentityRef.
1095      */
1096     memset(&creds, 0, sizeof(CSSM_ACCESS_CREDENTIALS));
1097     crtn = CSSM_CSP_CreateDeriveKeyContext(rawCspHand,
1098                 CSSM_ALGID_ECDH_X963_KDF,
1099                 ECDH_KEK_KEY_CSSM_ALGID,        // algorithm of the KEK
1100                 ECDH_KEK_KEY_LEN_BYTES * 8,
1101                 &creds,
1102                 &ourPrivKeyCssm,        // BaseKey
1103                 0,                      // IterationCount
1104                 &sharedInfoEnc,         // Salt
1105                 0,                      // Seed
1106                 &ccHand);
1107     if(crtn) {
1108         CSSM_PERROR("CSSM_CSP_CreateDeriveKeyContext", crtn);
1109         rv = crtn;
1110         goto loser;
1111     }
1112
1113     /* add recipient's pub key as a context attr */
1114     crtn = cmsAddContextAttribute(ccHand,
1115             CSSM_ATTRIBUTE_PUBLIC_KEY,
1116             sizeof(CSSM_KEY),
1117             CAT_Ptr,
1118             (void *)theirPubKeyCssm,
1119             0);
1120     if(crtn) {
1121         rv = crtn;
1122         goto loser;
1123     }
1124
1125     /* Derive the KEK */
1126     crtn = CSSM_DeriveKey(ccHand,
1127             &paramData,
1128             CSSM_KEYUSE_ANY,
1129             CSSM_KEYATTR_RETURN_DATA | CSSM_KEYATTR_EXTRACTABLE,
1130             &keyLabel,
1131             NULL,                               // cread/acl
1132             &kekDerive);
1133     if(crtn) {
1134         CSSM_PERROR("CSSM_DeriveKey", crtn);
1135         rv = crtn;
1136         goto loser;
1137     }
1138     CSSM_DeleteContext(ccHand);
1139     ccHand = 0;
1140
1141     /*
1142      * Obtain the raw CEK bits.
1143      */
1144     rv = SecKeyGetCSSMKey(key, &cekCssmRef);
1145     if(rv) {
1146         CSSM_PERROR("SecKeyGetCSSMKey", rv);
1147         goto loser;
1148     }
1149     rv = SecKeyGetCSPHandle(key, &refCspHand);
1150     if(rv) {
1151         CSSM_PERROR("SecKeyGetCSPHandle", rv);
1152         goto loser;
1153     }
1154     rv = cmsNullWrapKey(refCspHand, cekCssmRef, &cekCssm);
1155     if(rv) {
1156         goto loser;
1157     }
1158
1159     /*
1160      * Finally, encrypt the raw CEK bits with the KEK we just derived
1161      */
1162     crtn = CSSM_CSP_CreateSymmetricContext(rawCspHand,
1163             ECDH_KEK_ENCR_CSSM_ALGID,
1164             CSSM_ALGMODE_CBCPadIV8,
1165             NULL,                       // access cred
1166             &kekDerive,
1167             &ivData,                    // InitVector
1168             CSSM_PADDING_PKCS7,
1169             NULL,                       // Params
1170             &ccHand);
1171     if(rv) {
1172         CSSM_PERROR("CSSM_CSP_CreateSymmetricContext", rv);
1173         goto loser;
1174     }
1175     rv = CSSM_EncryptData(ccHand,
1176             &cekCssm.KeyData,
1177             1,
1178             &ctext,
1179             1,
1180             &bytesEncrypted,
1181             &remData);
1182     if(rv) {
1183         CSSM_PERROR("CSSM_EncryptData", rv);
1184         goto loser;
1185     }
1186     encKey->Data = PORT_ArenaAlloc(poolp, bytesEncrypted);
1187     encKey->Length = bytesEncrypted;
1188     memmove(encKey->Data, ctext.Data, ctext.Length);
1189     if(bytesEncrypted != ctext.Length) {
1190         memmove(encKey->Data + ctext.Length, remData.Data, remData.Length);
1191     }
1192     dumpBuf("sender encKey", encKey);
1193
1194 loser:
1195     if(ccHand) {
1196         CSSM_DeleteContext(ccHand);
1197     }
1198     CFRELEASE(theirPubKeyRef);
1199     if(ourPubKeyCssm.KeyData.Data) {
1200         CSSM_FreeKey(rawCspHand, NULL, &ourPubKeyCssm, CSSM_FALSE);
1201     }
1202     if(ourPrivKeyCssm.KeyData.Data) {
1203         CSSM_FreeKey(rawCspHand, NULL, &ourPrivKeyCssm, CSSM_FALSE);
1204     }
1205     if(ctext.Data) {
1206         cmsFreeCssmMemory(rawCspHand, ctext.Data);
1207     }
1208     if(remData.Data) {
1209         cmsFreeCssmMemory(rawCspHand, remData.Data);
1210     }
1211     if(cekCssm.KeyData.Data) {
1212         CSSM_FreeKey(refCspHand, NULL, &cekCssm, CSSM_FALSE);
1213     }
1214     if(kekDerive.KeyData.Data) {
1215         CSSM_FreeKey(rawCspHand, NULL, &kekDerive, CSSM_FALSE);
1216     }
1217     if(theirPubKeyCssm) {
1218         /* Allocated by CL */
1219         cmsFreeCssmMemory(clHand, theirPubKeyCssm->KeyData.Data);
1220         cmsFreeCssmMemory(clHand, theirPubKeyCssm);
1221     }
1222     return rv;
1223 }
1224
1225 #pragma mark ---- ECDH CEK key unwrap ----
1226
1227 SecSymmetricKeyRef
1228 SecCmsUtilDecryptSymKeyECDH(
1229     SecPrivateKeyRef privkey,   /* our private key */
1230     CSSM_DATA_PTR encKey,       /* encrypted CEK */
1231     CSSM_DATA_PTR ukm,          /* random UKM from KeyAgreeRecipientInfo.ukm */
1232     SECAlgorithmID *keyEncAlg,  /* alg := dhSinglePass-stdDH-sha1kdf-scheme
1233                                  * params := another encoded AlgId, with the KEK alg and IV */
1234     SECOidTag bulkalgtag,       /* algorithm of returned key */
1235     CSSM_DATA_PTR pubKey)       /* sender's pub key as ECPoint from
1236                                  * KeyAgreeRecipientInfo.originator.OriginatorPublicKey */
1237
1238 {
1239     SecSymmetricKeyRef outKey = NULL;
1240     OSStatus rv = noErr;
1241     const CSSM_KEY *ourPrivKeyCssm;
1242     PLArenaPool *pool = NULL;
1243     SECAlgorithmID keyAlgParam;
1244     SECOidData *kekOid = NULL;
1245     CSSM_DATA iv = {0, NULL};
1246     ECC_CMS_SharedInfo sharedInfo;
1247     CSSM_DATA sharedInfoEnc = {0, NULL};
1248     uint8 nullData[2] = {SEC_ASN1_NULL, 0};
1249     uint8 keyLenAsBytes[4];
1250     CSSM_ENCRYPT_MODE kekMode;
1251     uint32 kekSizeBits;
1252     CSSM_KEY kekDerive;
1253     CSSM_RETURN crtn;
1254     CSSM_ACCESS_CREDENTIALS creds;
1255     CSSM_CSP_HANDLE refCspHand;
1256     CSSM_CC_HANDLE ccHand = 0;
1257     CSSM_DATA keyLabel = {8, (uint8 *)"tempKey"};
1258     const CSSM_ACCESS_CREDENTIALS *accessCred;
1259     CSSM_KEY wrappedKey;
1260     CSSM_KEY unwrappedKey;
1261     CSSM_ALGORITHMS bulkAlg;
1262     CSSM_DATA descriptiveData = {0, NULL};
1263
1264     dumpBuf("receiver encKey", encKey);
1265
1266     memset(&kekDerive, 0, sizeof(kekDerive));
1267
1268     /* our private key in CSSM form */
1269     rv = SecKeyGetCSSMKey(privkey, &ourPrivKeyCssm);
1270     if(rv) {
1271         CSSM_PERROR("SecKeyGetCSSMKey", rv);
1272         goto loser;
1273     }
1274
1275     /*
1276      * Decode keyEncAlg.params to get KEK algorithm and IV
1277      */
1278     pool = PORT_NewArena(1024);
1279     if(pool == NULL) {
1280         goto loser;
1281     }
1282     memset(&keyAlgParam, 0, sizeof(keyAlgParam));
1283     if(SEC_ASN1DecodeItem(pool, &keyAlgParam, SECOID_AlgorithmIDTemplate,
1284             &keyEncAlg->parameters)) {
1285         dprintf("SecCmsUtilDecryptSymKeyECDH: error decoding keyAlgParams\n");
1286         goto loser;
1287     }
1288     kekOid = SECOID_FindOID(&keyAlgParam.algorithm);
1289     if(kekOid == NULL) {
1290         dprintf("SecCmsUtilDecryptSymKeyECDH: unknown KEK enc OID\n");
1291         goto loser;
1292     }
1293     rv = encrAlgInfo(kekOid->offset, &kekSizeBits, &kekMode);
1294     if(rv) {
1295         goto loser;
1296     }
1297     /* IV is OCTET STRING in the alg params */
1298     if(SEC_ASN1DecodeItem(pool, &iv, kSecAsn1OctetStringTemplate,
1299             &keyAlgParam.parameters)) {
1300         /*
1301          * Not sure here - is it legal to have no IV? I haven't seen this
1302          * addressed in any spec. Maybe we should condition the behavior
1303          * here on the KEK algorithm.
1304          */
1305         dprintf("SecCmsUtilDecryptSymKeyECDH: no KEK IV\n");
1306         goto loser;
1307     }
1308
1309     /*
1310      * Now in order to derive the KEK proper, we have to create a
1311      * ECC-CMS-SharedInfo, which does not appear in the message, and DER
1312      * encode that struct, the result of which is used as the
1313      * SharedInfo value in the KEK key derive.
1314      */
1315     memset(&sharedInfo, 0, sizeof(sharedInfo));
1316     sharedInfo.algId.algorithm = kekOid->oid;
1317     sharedInfo.algId.parameters.Data = nullData;
1318     sharedInfo.algId.parameters.Length = 2;
1319     sharedInfo.entityUInfo = *ukm;
1320     int32ToBytes(kekSizeBits, keyLenAsBytes);
1321     sharedInfo.suppPubInfo.Length = 4;
1322     sharedInfo.suppPubInfo.Data = keyLenAsBytes;
1323     if (!SEC_ASN1EncodeItem(pool, &sharedInfoEnc,
1324             &sharedInfo, ECC_CMS_SharedInfoTemplate)) {
1325         rv = internalComponentErr;
1326         goto loser;
1327     }
1328     dumpBuf("receiver encoded SharedInfo", &sharedInfoEnc);
1329     dumpBuf("receiver IV", &iv);
1330     dumpBuf("receiver UKM", ukm);
1331     dumpBuf("sender's public key", pubKey);
1332
1333     /*
1334      * Using the Sec-layer CSPDL, "other's" public key specified as ECPOint param. Which
1335      * is fortunate because that's what we have...
1336      */
1337     memset(&creds, 0, sizeof(CSSM_ACCESS_CREDENTIALS));
1338     rv = SecKeyGetCSPHandle(privkey, &refCspHand);
1339     if(rv) {
1340         CSSM_PERROR("SecKeyGetCSPHandle", rv);
1341         goto loser;
1342     }
1343     rv = SecKeyGetCredentials(privkey,
1344             CSSM_ACL_AUTHORIZATION_DERIVE,
1345             kSecCredentialTypeDefault,
1346             &accessCred);
1347     if (rv) {
1348         CSSM_PERROR("SecKeyGetCredentials", rv);
1349         goto loser;
1350     }
1351     crtn = CSSM_CSP_CreateDeriveKeyContext(refCspHand,
1352                 CSSM_ALGID_ECDH_X963_KDF,
1353                 kekOid->cssmAlgorithm,  // algorithm of the KEK
1354                 kekSizeBits,
1355                 &creds,
1356                 ourPrivKeyCssm,         // BaseKey
1357                 0,                      // IterationCount
1358                 &sharedInfoEnc,         // Salt
1359                 0,                      // Seed
1360                 &ccHand);
1361     if(crtn) {
1362         CSSM_PERROR("CSSM_CSP_CreateDeriveKeyContext", crtn);
1363         goto loser;
1364     }
1365     crtn = CSSM_DeriveKey(ccHand,
1366             pubKey,                     // param
1367             CSSM_KEYUSE_ANY,
1368             CSSM_KEYATTR_RETURN_REF | CSSM_KEYATTR_EXTRACTABLE,
1369             &keyLabel,
1370             NULL,                       // cred/acl
1371             &kekDerive);
1372     CSSM_DeleteContext(ccHand);
1373     ccHand = 0;
1374     if(crtn) {
1375         CSSM_PERROR("CSSM_DeriveKey", crtn);
1376         goto loser;
1377     }
1378
1379     /*
1380      * Decrypt the encrypted key bits with the KEK key.
1381      */
1382     crtn = CSSM_CSP_CreateSymmetricContext(refCspHand,
1383             kekOid->cssmAlgorithm,
1384             kekMode,
1385             NULL,                       // access cred
1386             &kekDerive,
1387             &iv,                        // InitVector
1388             /* FIXME is this variable too? */
1389             CSSM_PADDING_PKCS7,
1390             NULL,                       // Params
1391             &ccHand);
1392     if(rv) {
1393         CSSM_PERROR("CSSM_CSP_CreateSymmetricContext", rv);
1394         goto loser;
1395     }
1396
1397     memset(&wrappedKey, 0, sizeof(CSSM_KEY));
1398     memset(&unwrappedKey, 0, sizeof(CSSM_KEY));
1399
1400     bulkAlg = SECOID_FindyCssmAlgorithmByTag(bulkalgtag);
1401     if(bulkAlg == CSSM_ALGID_NONE) {
1402         dprintf("SecCmsUtilDecryptSymKeyECDH: unknown bulk alg\n");
1403         goto loser;
1404     }
1405
1406     wrappedKey.KeyHeader.HeaderVersion = CSSM_KEYHEADER_VERSION;
1407     wrappedKey.KeyHeader.BlobType = CSSM_KEYBLOB_WRAPPED;
1408     wrappedKey.KeyHeader.Format = CSSM_KEYBLOB_WRAPPED_FORMAT_PKCS7;
1409     wrappedKey.KeyHeader.AlgorithmId = bulkAlg;
1410     wrappedKey.KeyHeader.KeyClass = CSSM_KEYCLASS_SESSION_KEY;
1411     wrappedKey.KeyHeader.WrapAlgorithmId = kekOid->cssmAlgorithm;
1412     wrappedKey.KeyHeader.WrapMode = CSSM_ALGMODE_NONE;
1413     wrappedKey.KeyData = *encKey;
1414
1415     crtn = CSSM_UnwrapKey(ccHand,
1416             NULL, /* publicKey */
1417             &wrappedKey,
1418             CSSM_KEYUSE_DECRYPT,
1419             CSSM_KEYATTR_EXTRACTABLE,
1420             &keyLabel,
1421             NULL, /* rcc */
1422             &unwrappedKey,
1423             &descriptiveData);
1424     CSSM_DeleteContext(ccHand);
1425     ccHand = 0;
1426     if(crtn) {
1427         CSSM_PERROR("CSSM_UnwrapKey", crtn);
1428         goto loser;
1429     }
1430     rv = SecKeyCreateWithCSSMKey(&unwrappedKey, &outKey);
1431     if (rv) {
1432         CSSM_PERROR("SecKeyCreateWithCSSMKey", rv);
1433     }
1434
1435 loser:
1436     if(pool != NULL) {
1437         PORT_FreeArena(pool, PR_FALSE);
1438     }
1439     if(kekDerive.KeyData.Data) {
1440         CSSM_FreeKey(refCspHand, NULL, &kekDerive, CSSM_FALSE);
1441     }
1442     if(outKey == NULL) {
1443         PORT_SetError(SEC_ERROR_NO_KEY);
1444     }
1445     return outKey;
1446 }
1447
1448
1449