Security/libsecurity_smime/lib/cmsenvdata.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 envelopedData methods.
  36  */
  37
  38 #include <Security/SecCmsEnvelopedData.h>
  39
  40 #include <Security/SecCmsContentInfo.h>
  41 #include <Security/SecCmsRecipientInfo.h>
  42
  43 #include "cmslocal.h"
  44
  45 #include "secitem.h"
  46 #include "secoid.h"
  47 #include "cryptohi.h"
  48
  49 #include <security_asn1/secasn1.h>
  50 #include <security_asn1/secerr.h>
  51 #include <Security/SecKeyPriv.h>
  52
  53 /*
  54  * SecCmsEnvelopedDataCreate - create an enveloped data message
  55  */
  56 SecCmsEnvelopedDataRef
  57 SecCmsEnvelopedDataCreate(SecCmsMessageRef cmsg, SECOidTag algorithm, int keysize)
  58 {
  59     void *mark;
  60     SecCmsEnvelopedDataRef envd;
  61     PLArenaPool *poolp;
  62     OSStatus rv;
  63
  64     poolp = cmsg->poolp;
  65
  66     mark = PORT_ArenaMark(poolp);
  67
  68     envd = (SecCmsEnvelopedDataRef)PORT_ArenaZAlloc(poolp, sizeof(SecCmsEnvelopedData));
  69     if (envd == NULL)
  70         goto loser;
  71
  72     envd->cmsg = cmsg;
  73
  74     /* version is set in SecCmsEnvelopedDataEncodeBeforeStart() */
  75
  76     rv = SecCmsContentInfoSetContentEncAlg((SecArenaPoolRef)poolp, &(envd->contentInfo), algorithm, NULL, keysize);
  77     if (rv != SECSuccess)
  78         goto loser;
  79
  80     PORT_ArenaUnmark(poolp, mark);
  81     return envd;
  82
  83 loser:
  84     PORT_ArenaRelease(poolp, mark);
  85     return NULL;
  86 }
  87
  88 /*
  89  * SecCmsEnvelopedDataDestroy - destroy an enveloped data message
  90  */
  91 void
  92 SecCmsEnvelopedDataDestroy(SecCmsEnvelopedDataRef edp)
  93 {
  94     SecCmsRecipientInfoRef *recipientinfos;
  95     SecCmsRecipientInfoRef ri;
  96
  97     if (edp == NULL)
  98         return;
  99
 100     recipientinfos = edp->recipientInfos;
 101     if (recipientinfos == NULL)
 102         return;
 103
 104     while ((ri = *recipientinfos++) != NULL)
 105         SecCmsRecipientInfoDestroy(ri);
 106
 107    SecCmsContentInfoDestroy(&(edp->contentInfo));
 108
 109 }
 110
 111 /*
 112  * SecCmsEnvelopedDataGetContentInfo - return pointer to this envelopedData's contentinfo
 113  */
 114 SecCmsContentInfoRef
 115 SecCmsEnvelopedDataGetContentInfo(SecCmsEnvelopedDataRef envd)
 116 {
 117     return &(envd->contentInfo);
 118 }
 119
 120 /*
 121  * SecCmsEnvelopedDataAddRecipient - add a recipientinfo to the enveloped data msg
 122  *
 123  * rip must be created on the same pool as edp - this is not enforced, though.
 124  */
 125 OSStatus
 126 SecCmsEnvelopedDataAddRecipient(SecCmsEnvelopedDataRef edp, SecCmsRecipientInfoRef rip)
 127 {
 128     void *mark;
 129     OSStatus rv;
 130
 131     /* XXX compare pools, if not same, copy rip into edp's pool */
 132
 133     PR_ASSERT(edp != NULL);
 134     PR_ASSERT(rip != NULL);
 135
 136     mark = PORT_ArenaMark(edp->cmsg->poolp);
 137
 138     rv = SecCmsArrayAdd(edp->cmsg->poolp, (void ***)&(edp->recipientInfos), (void *)rip);
 139     if (rv != SECSuccess) {
 140         PORT_ArenaRelease(edp->cmsg->poolp, mark);
 141         return SECFailure;
 142     }
 143
 144     PORT_ArenaUnmark (edp->cmsg->poolp, mark);
 145     return SECSuccess;
 146 }
 147
 148 /*
 149  * SecCmsEnvelopedDataEncodeBeforeStart - prepare this envelopedData for encoding
 150  *
 151  * at this point, we need
 152  * - recipientinfos set up with recipient's certificates
 153  * - a content encryption algorithm (if none, 3DES will be used)
 154  *
 155  * this function will generate a random content encryption key (aka bulk key),
 156  * initialize the recipientinfos with certificate identification and wrap the bulk key
 157  * using the proper algorithm for every certificiate.
 158  * it will finally set the bulk algorithm and key so that the encode step can find it.
 159  */
 160 OSStatus
 161 SecCmsEnvelopedDataEncodeBeforeStart(SecCmsEnvelopedDataRef envd)
 162 {
 163     int version;
 164     SecCmsRecipientInfoRef *recipientinfos;
 165     SecCmsContentInfoRef cinfo;
 166     SecSymmetricKeyRef bulkkey = NULL;
 167     CSSM_ALGORITHMS algorithm;
 168     SECOidTag bulkalgtag;
 169     //CK_MECHANISM_TYPE type;
 170     //PK11SlotInfo *slot;
 171     OSStatus rv;
 172     CSSM_DATA_PTR dummy;
 173     PLArenaPool *poolp;
 174     extern const SecAsn1Template SecCmsRecipientInfoTemplate[];
 175     void *mark = NULL;
 176     int i;
 177
 178     poolp = envd->cmsg->poolp;
 179     cinfo = &(envd->contentInfo);
 180
 181     recipientinfos = envd->recipientInfos;
 182     if (recipientinfos == NULL) {
 183         PORT_SetError(SEC_ERROR_BAD_DATA);
 184 #if 0
 185         PORT_SetErrorString("Cannot find recipientinfos to encode.");
 186 #endif
 187         goto loser;
 188     }
 189
 190     version = SEC_CMS_ENVELOPED_DATA_VERSION_REG;
 191     if (envd->originatorInfo != NULL || envd->unprotectedAttr != NULL) {
 192         version = SEC_CMS_ENVELOPED_DATA_VERSION_ADV;
 193     } else {
 194         for (i = 0; recipientinfos[i] != NULL; i++) {
 195             if (SecCmsRecipientInfoGetVersion(recipientinfos[i]) != 0) {
 196                 version = SEC_CMS_ENVELOPED_DATA_VERSION_ADV;
 197                 break;
 198             }
 199         }
 200     }
 201     dummy = SEC_ASN1EncodeInteger(poolp, &(envd->version), version);
 202     if (dummy == NULL)
 203         goto loser;
 204
 205     /* now we need to have a proper content encryption algorithm
 206      * on the SMIME level, we would figure one out by looking at SMIME capabilities
 207      * we cannot do that on our level, so if none is set already, we'll just go
 208      * with one of the mandatory algorithms (3DES) */
 209     if ((bulkalgtag = SecCmsContentInfoGetContentEncAlgTag(cinfo)) == SEC_OID_UNKNOWN) {
 210         rv = SecCmsContentInfoSetContentEncAlg((SecArenaPoolRef)poolp, cinfo, SEC_OID_DES_EDE3_CBC, NULL, 168);
 211         if (rv != SECSuccess)
 212             goto loser;
 213         bulkalgtag = SEC_OID_DES_EDE3_CBC;
 214     }
 215
 216     algorithm = SECOID_FindyCssmAlgorithmByTag(bulkalgtag);
 217     if (!algorithm)
 218         goto loser;
 219     rv = SecKeyGenerate(NULL,   /* keychainRef */
 220                 algorithm,
 221                 SecCmsContentInfoGetBulkKeySize(cinfo),
 222                 0,              /* contextHandle */
 223                 CSSM_KEYUSE_ENCRYPT | CSSM_KEYUSE_DECRYPT,
 224                 CSSM_KEYATTR_EXTRACTABLE,
 225                 NULL,           /* initialAccess */
 226                 &bulkkey);
 227     if (rv)
 228         goto loser;
 229
 230     mark = PORT_ArenaMark(poolp);
 231
 232     /* Encrypt the bulk key with the public key of each recipient.  */
 233     for (i = 0; recipientinfos[i] != NULL; i++) {
 234         rv = SecCmsRecipientInfoWrapBulkKey(recipientinfos[i], bulkkey, bulkalgtag);
 235         if (rv != SECSuccess)
 236             goto loser; /* error has been set by SecCmsRecipientInfoEncryptBulkKey */
 237                         /* could be: alg not supported etc. */
 238     }
 239
 240     /* the recipientinfos are all finished. now sort them by DER for SET OF encoding */
 241     rv = SecCmsArraySortByDER((void **)envd->recipientInfos, SecCmsRecipientInfoTemplate, NULL);
 242     if (rv != SECSuccess)
 243         goto loser;     /* error has been set by SecCmsArraySortByDER */
 244
 245     /* store the bulk key in the contentInfo so that the encoder can find it */
 246     SecCmsContentInfoSetBulkKey(cinfo, bulkkey);
 247
 248     PORT_ArenaUnmark(poolp, mark);
 249
 250     CFRelease(bulkkey);
 251
 252     return SECSuccess;
 253
 254 loser:
 255     if (mark != NULL)
 256         PORT_ArenaRelease (poolp, mark);
 257     if (bulkkey)
 258         CFRelease(bulkkey);
 259
 260     return SECFailure;
 261 }
 262
 263 /*
 264  * SecCmsEnvelopedDataEncodeBeforeData - set up encryption
 265  *
 266  * it is essential that this is called before the contentEncAlg is encoded, because
 267  * setting up the encryption may generate IVs and thus change it!
 268  */
 269 OSStatus
 270 SecCmsEnvelopedDataEncodeBeforeData(SecCmsEnvelopedDataRef envd)
 271 {
 272     SecCmsContentInfoRef cinfo;
 273     SecSymmetricKeyRef bulkkey;
 274     SECAlgorithmID *algid;
 275
 276     cinfo = &(envd->contentInfo);
 277
 278     /* find bulkkey and algorithm - must have been set by SecCmsEnvelopedDataEncodeBeforeStart */
 279     bulkkey = SecCmsContentInfoGetBulkKey(cinfo);
 280     if (bulkkey == NULL)
 281         return SECFailure;
 282     algid = SecCmsContentInfoGetContentEncAlg(cinfo);
 283     if (algid == NULL)
 284         return SECFailure;
 285
 286     /* this may modify algid (with IVs generated in a token).
 287      * it is essential that algid is a pointer to the contentEncAlg data, not a
 288      * pointer to a copy! */
 289     cinfo->ciphcx = SecCmsCipherContextStartEncrypt(envd->cmsg->poolp, bulkkey, algid);
 290     CFRelease(bulkkey);
 291     if (cinfo->ciphcx == NULL)
 292         return SECFailure;
 293
 294     return SECSuccess;
 295 }
 296
 297 /*
 298  * SecCmsEnvelopedDataEncodeAfterData - finalize this envelopedData for encoding
 299  */
 300 OSStatus
 301 SecCmsEnvelopedDataEncodeAfterData(SecCmsEnvelopedDataRef envd)
 302 {
 303     if (envd->contentInfo.ciphcx) {
 304         SecCmsCipherContextDestroy(envd->contentInfo.ciphcx);
 305         envd->contentInfo.ciphcx = NULL;
 306     }
 307
 308     /* nothing else to do after data */
 309     return SECSuccess;
 310 }
 311
 312 /*
 313  * SecCmsEnvelopedDataDecodeBeforeData - find our recipientinfo,
 314  * derive bulk key & set up our contentinfo
 315  */
 316 OSStatus
 317 SecCmsEnvelopedDataDecodeBeforeData(SecCmsEnvelopedDataRef envd)
 318 {
 319     SecCmsRecipientInfoRef ri;
 320     SecSymmetricKeyRef bulkkey = NULL;
 321     SECOidTag bulkalgtag;
 322     SECAlgorithmID *bulkalg;
 323     OSStatus rv = SECFailure;
 324     SecCmsContentInfoRef cinfo;
 325     SecCmsRecipient **recipient_list = NULL;
 326     SecCmsRecipient *recipient;
 327     int rlIndex;
 328
 329     if (SecCmsArrayCount((void **)envd->recipientInfos) == 0) {
 330         PORT_SetError(SEC_ERROR_BAD_DATA);
 331 #if 0
 332         PORT_SetErrorString("No recipient data in envelope.");
 333 #endif
 334         goto loser;
 335     }
 336
 337     /* look if one of OUR cert's issuerSN is on the list of recipients, and if so,  */
 338     /* get the cert and private key for it right away */
 339     recipient_list = nss_cms_recipient_list_create(envd->recipientInfos);
 340     if (recipient_list == NULL)
 341         goto loser;
 342
 343     /* what about multiple recipientInfos that match?
 344      * especially if, for some reason, we could not produce a bulk key with the first match?!
 345      * we could loop & feed partial recipient_list to PK11_FindCertAndKeyByRecipientList...
 346      * maybe later... */
 347     rlIndex = nss_cms_FindCertAndKeyByRecipientList(recipient_list, envd->cmsg->pwfn_arg);
 348
 349     /* if that fails, then we're not an intended recipient and cannot decrypt */
 350     if (rlIndex < 0) {
 351         PORT_SetError(SEC_ERROR_NOT_A_RECIPIENT);
 352 #if 0
 353         PORT_SetErrorString("Cannot decrypt data because proper key cannot be found.");
 354 #endif
 355         goto loser;
 356     }
 357
 358     recipient = recipient_list[rlIndex];
 359     if (!recipient->cert || !recipient->privkey) {
 360         /* XXX should set an error code ?!? */
 361         goto loser;
 362     }
 363     /* get a pointer to "our" recipientinfo */
 364     ri = envd->recipientInfos[recipient->riIndex];
 365
 366     cinfo = &(envd->contentInfo);
 367     bulkalgtag = SecCmsContentInfoGetContentEncAlgTag(cinfo);
 368     if (bulkalgtag == SEC_OID_UNKNOWN) {
 369         PORT_SetError(SEC_ERROR_INVALID_ALGORITHM);
 370     } else
 371         bulkkey = SecCmsRecipientInfoUnwrapBulkKey(ri,recipient->subIndex,
 372                                                     recipient->cert,
 373                                                     recipient->privkey,
 374                                                     bulkalgtag);
 375     if (bulkkey == NULL) {
 376         /* no success finding a bulk key */
 377         rv = errSecDataNotAvailable;
 378         goto loser;
 379     }
 380
 381     SecCmsContentInfoSetBulkKey(cinfo, bulkkey);
 382     // @@@ See 3401088 for details.  We need to CFRelease cinfo->bulkkey before recipient->privkey gets CFReleased. It's created with SecKeyCreateWithCSSMKey which is not safe currently.  If the private key's SecKeyRef from which we extracted the CSP gets CFRelease before the builkkey does we crash.  We should really fix SecKeyCreateWithCSSMKey which is a huge hack currently.  To work around this we add recipient->privkey to the cinfo so it gets when cinfo is destroyed.
 383     CFRetain(recipient->privkey);
 384     cinfo->privkey = recipient->privkey;
 385
 386     bulkalg = SecCmsContentInfoGetContentEncAlg(cinfo);
 387
 388     cinfo->ciphcx = SecCmsCipherContextStartDecrypt(bulkkey, bulkalg);
 389     if (cinfo->ciphcx == NULL)
 390         goto loser;             /* error has been set by SecCmsCipherContextStartDecrypt */
 391
 392 #if 1
 393     // @@@ Fix me
 394 #else
 395     /*
 396      * HACK ALERT!!
 397      * For PKCS5 Encryption Algorithms, the bulkkey is actually a different
 398      * structure.  Therefore, we need to set the bulkkey to the actual key
 399      * prior to freeing it.
 400      */
 401     if (SEC_PKCS5IsAlgorithmPBEAlg(bulkalg)) {
 402         SEC_PKCS5KeyAndPassword *keyPwd = (SEC_PKCS5KeyAndPassword *)bulkkey;
 403         bulkkey = keyPwd->key;
 404     }
 405 #endif
 406
 407     rv = SECSuccess;
 408
 409 loser:
 410     if (bulkkey)
 411         CFRelease(bulkkey);
 412     if (recipient_list != NULL)
 413         nss_cms_recipient_list_destroy(recipient_list);
 414     return rv;
 415 }
 416
 417 /*
 418  * SecCmsEnvelopedDataDecodeAfterData - finish decrypting this envelopedData's content
 419  */
 420 OSStatus
 421 SecCmsEnvelopedDataDecodeAfterData(SecCmsEnvelopedDataRef envd)
 422 {
 423     if (envd && envd->contentInfo.ciphcx) {
 424         SecCmsCipherContextDestroy(envd->contentInfo.ciphcx);
 425         envd->contentInfo.ciphcx = NULL;
 426     }
 427
 428     return SECSuccess;
 429 }
 430
 431 /*
 432  * SecCmsEnvelopedDataDecodeAfterEnd - finish decoding this envelopedData
 433  */
 434 OSStatus
 435 SecCmsEnvelopedDataDecodeAfterEnd(SecCmsEnvelopedDataRef envd)
 436 {
 437     /* apply final touches */
 438     return SECSuccess;
 439 }
 440