libsecurity_smime/lib/CMSEncoder.h

   1 /*
   2  * Copyright (c) 2006-2012 Apple Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 /*
  25  * CMSEncoder.h - encode, sign, and/or encrypt messages in the Cryptographic
  26  *                                Message Syntax (CMS), per RFC 3852.
  27  *
  28  * A CMS message can be signed, encrypted, or both. A message can be signed by
  29  * an arbitrary number of signers; in this module, signers are expressed as
  30  * SecIdentityRefs. A message can be encrypted for an arbitrary number of
  31  * recipients; recipients are expressed here as SecCertificateRefs.
  32  *
  33  * In CMS terminology, this module performs encryption using the EnvelopedData
  34  * ContentType and signing using the SignedData ContentType.
  35  *
  36  * If the message is both signed and encrypted, it uses "nested ContentInfos"
  37  * in CMS terminology; in this implementation, signed & encrypted messages
  38  * are implemented as an EnvelopedData containing a SignedData.
  39  */
  40
  41 #ifndef _CMS_ENCODER_H_
  42 #define _CMS_ENCODER_H_
  43
  44 #include <CoreFoundation/CoreFoundation.h>
  45 #include <Security/SecCmsEncoder.h>
  46 #include <Security/SecCmsDecoder.h>
  47 #include <Security/SecCmsMessage.h>
  48 #include <AvailabilityMacros.h>
  49 #include <stdint.h>
  50
  51 __BEGIN_DECLS
  52
  53 CF_ASSUME_NONNULL_BEGIN
  54
  55 /*
  56  * Opaque reference to a CMS encoder object.
  57  * This is a CF object, with standard CF semantics; dispose of it
  58  * with CFRelease().
  59  */
  60 typedef struct CF_BRIDGED_TYPE(id) _CMSEncoder *CMSEncoderRef;
  61
  62 CFTypeID CMSEncoderGetTypeID(void)
  63     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
  64
  65 /*
  66  * Create a CMSEncoder. Result must eventually be freed via CFRelease().
  67  */
  68 OSStatus CMSEncoderCreate(CMSEncoderRef * __nonnull CF_RETURNS_RETAINED cmsEncoderOut)  /* RETURNED */
  69     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
  70
  71 extern const CFStringRef kCMSEncoderDigestAlgorithmSHA1;
  72 extern const CFStringRef kCMSEncoderDigestAlgorithmSHA256;
  73
  74 OSStatus CMSEncoderSetSignerAlgorithm(
  75     CMSEncoderRef               cmsEncoder,
  76     CFStringRef         digestAlgorithm)
  77     __OSX_AVAILABLE_STARTING(__MAC_10_11, __IPHONE_11_0);
  78
  79 /*
  80  * Specify signers of the CMS message; implies that the message will be signed.
  81  *
  82  * -- Caller can pass in one signer, as a SecIdentityRef, or an array of
  83  *    signers, as a CFArray of SecIdentityRefs.
  84  * -- Can be called multiple times.
  85  * -- If the message is not to be signed, don't call this.
  86  * -- If this is called, it must be called before the first call to
  87  *    CMSEncoderUpdateContent().
  88  */
  89 OSStatus CMSEncoderAddSigners(
  90     CMSEncoderRef               cmsEncoder,
  91     CFTypeRef                   signerOrArray)
  92     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
  93
  94 /*
  95  * Obtain an array of signers as specified in CMSEncoderSetSigners().
  96  * Returns a NULL signers array if CMSEncoderSetSigners() has not been called.
  97  * Caller must CFRelease the result.
  98  */
  99 OSStatus CMSEncoderCopySigners(
 100     CMSEncoderRef               cmsEncoder,
 101     CFArrayRef * __nonnull CF_RETURNS_RETAINED signersOut)              /* RETURNED */
 102     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
 103
 104 /*
 105  * Specify recipients of the message. Implies that the message will
 106  * be encrypted.
 107  *
 108  * -- Caller can pass in one recipient, as a SecCertificateRef, or an
 109  *    array of recipients, as a CFArray of SecCertificateRefs.
 110  * -- Can be called multiple times.
 111  * -- If the message is not to be encrypted, don't call this.
 112  * -- If this is called, it must be called before the first call to
 113  *    CMSEncoderUpdateContent().
 114  */
 115 OSStatus CMSEncoderAddRecipients(
 116     CMSEncoderRef               cmsEncoder,
 117     CFTypeRef                   recipientOrArray)
 118     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
 119
 120 /*
 121  * Obtain an array of recipients as specified in CMSEncoderSetRecipients().
 122  * Returns a NULL recipients array if CMSEncoderSetRecipients() has not been
 123  * called.
 124  * Caller must CFRelease the result.
 125  */
 126 OSStatus CMSEncoderCopyRecipients(
 127     CMSEncoderRef               cmsEncoder,
 128     CFArrayRef * __nonnull CF_RETURNS_RETAINED recipientsOut)   /* RETURNED */
 129     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
 130
 131 /*
 132  * A signed message optionally includes the data to be signed. If the message
 133  * is *not* to include the data to be signed, call this function with a value
 134  * of TRUE for detachedContent. The default, if this function is not called,
 135  * is detachedContent=FALSE, i.e., the message contains the data to be signed.
 136  *
 137  * -- Encrypted messages can not use detached content. (This restriction
 138  *    also applies to messages that are both signed and encrypted.)
 139  * -- If this is called, it must be called before the first call to
 140  *    CMSEncoderUpdateContent().
 141  */
 142 OSStatus CMSEncoderSetHasDetachedContent(
 143     CMSEncoderRef               cmsEncoder,
 144     Boolean                     detachedContent)
 145     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
 146
 147 /*
 148  * Obtain a Boolean indicating whether the current message will have detached
 149  * content.
 150  * Returns the value specified in CMSEncoderHasDetachedContent() if that
 151  * function has been called; else returns the default FALSE.
 152  */
 153 OSStatus CMSEncoderGetHasDetachedContent(
 154     CMSEncoderRef               cmsEncoder,
 155     Boolean                     *detachedContentOut)    /* RETURNED */
 156     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
 157
 158 /*
 159  * Optionally specify an eContentType OID for the inner EncapsulatedData for
 160  * a signed message. The default eContentTypeOID, used if this function is not
 161  * called, is id-data (which is the normal eContentType for applications such
 162  * as SMIME).
 163  *
 164  * The eContentTypeOID parameter may be specified as a CF string, e.g.:
 165  * CFSTR("1.2.840.113549.1.7.1")
 166  *
 167  * If this is called, it must be called before the first call to
 168  * CMSEncoderUpdateContent().
 169  */
 170 OSStatus CMSEncoderSetEncapsulatedContentTypeOID(
 171     CMSEncoderRef               cmsEncoder,
 172     CFTypeRef                   eContentTypeOID)
 173     __OSX_AVAILABLE_STARTING(__MAC_10_7, __IPHONE_11_0);
 174
 175 /*
 176  * Obtain the eContentType OID specified in CMSEncoderSetEncapsulatedContentType().
 177  * If CMSEncoderSetEncapsulatedContentType() has not been called this returns a
 178  * NULL pointer.
 179  * The returned OID's data is in the same format as the data provided to
 180  * CMSEncoderSetEncapsulatedContentType;, i.e., it's the encoded content of
 181  * the OID, not including the tag and length bytes.
 182  */
 183 OSStatus CMSEncoderCopyEncapsulatedContentType(
 184     CMSEncoderRef               cmsEncoder,
 185     CFDataRef * __nonnull CF_RETURNS_RETAINED eContentTypeOut)          /* RETURNED */
 186     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
 187
 188 /*
 189  * Signed CMS messages can contain arbitrary sets of certificates beyond those
 190  * indicating the identity of the signer(s). This function provides a means of
 191  * adding these other certs. For normal signed messages it is not necessary to
 192  * call this; the signer cert(s) and the intermediate certs needed to verify the
 193  * signer(s) will be included in the message implicitly.
 194  *
 195  * -- Caller can pass in one cert, as a SecCertificateRef, or an array of certs,
 196  *    as a CFArray of SecCertificateRefs.
 197  * -- If this is called, it must be called before the first call to
 198  *    CMSEncoderUpdateContent().
 199  * -- There is a "special case" use of CMS messages which involves neither
 200  *    signing nor encryption, but does include certificates. This is commonly
 201  *    used to transport "bags" of certificates. When constructing such a
 202  *    message, all an application needs to do is to create a CMSEncoderRef,
 203  *    call CMSEncoderAddSupportingCerts() one or more times, and then call
 204  *    CMSEncoderCopyEncodedContent() to get the resulting cert bag. No 'content'
 205  *    need be specified. (This is in fact the primary intended use for
 206  *    this function.)
 207  */
 208 OSStatus CMSEncoderAddSupportingCerts(
 209     CMSEncoderRef               cmsEncoder,
 210     CFTypeRef                   certOrArray)
 211     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
 212
 213 /*
 214  * Obtain the SecCertificates provided in CMSEncoderAddSupportingCerts().
 215  * If CMSEncoderAddSupportingCerts() has not been called this will return a
 216  * NULL value for *certs.
 217  * Caller must CFRelease the result.
 218  */
 219 OSStatus CMSEncoderCopySupportingCerts(
 220     CMSEncoderRef               cmsEncoder,
 221     CFArrayRef * __nonnull CF_RETURNS_RETAINED certsOut)                        /* RETURNED */
 222     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
 223
 224 /*
 225  * Standard signed attributes, optionally specified in
 226  * CMSEncoderAddSignedAttributes().
 227  */
 228 typedef CF_OPTIONS(uint32_t, CMSSignedAttributes) {
 229     kCMSAttrNone                                                = 0x0000,
 230     /*
 231      * S/MIME Capabilities - identifies supported signature, encryption, and
 232      * digest algorithms.
 233      */
 234     kCMSAttrSmimeCapabilities                   = 0x0001,
 235     /*
 236      * Indicates that a cert is the preferred cert for S/MIME encryption.
 237      */
 238     kCMSAttrSmimeEncryptionKeyPrefs             = 0x0002,
 239     /*
 240      * Same as kCMSSmimeEncryptionKeyPrefs, using an attribute OID preferred
 241      * by Microsoft.
 242      */
 243     kCMSAttrSmimeMSEncryptionKeyPrefs   = 0x0004,
 244     /*
 245      * Include the signing time.
 246      */
 247     kCMSAttrSigningTime                                 = 0x0008,
 248     /*
 249      * Include the Apple Codesigning Hash Agility.
 250      */
 251     kCMSAttrAppleCodesigningHashAgility = 0x0010
 252 };
 253
 254 /*
 255  * Optionally specify signed attributes. Only meaningful when creating a
 256  * signed message. If this is called, it must be called before
 257  * CMSEncoderUpdateContent().
 258  */
 259 OSStatus CMSEncoderAddSignedAttributes(
 260     CMSEncoderRef               cmsEncoder,
 261     CMSSignedAttributes signedAttributes)
 262     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
 263
 264 /*
 265  * Specification of what certificates to include in a signed message.
 266  */
 267 typedef CF_ENUM(uint32_t, CMSCertificateChainMode) {
 268     kCMSCertificateNone = 0,            /* don't include any certificates */
 269     kCMSCertificateSignerOnly,          /* only include signer certificate(s) */
 270     kCMSCertificateChain,                       /* signer certificate chain up to but not
 271                                      *   including root certiticate */
 272     kCMSCertificateChainWithRoot        /* signer certificate chain including root */
 273 };
 274
 275 /*
 276  * Optionally specify which certificates, if any, to include in a
 277  * signed CMS message. The default, if this is not called, is
 278  * kCMSCertificateChain, in which case the signer cert plus all CA
 279  * certs needed to verify the signer cert, except for the root
 280  * cert, are included.
 281  * If this is called, it must be called before
 282  * CMSEncoderUpdateContent().
 283  */
 284 OSStatus CMSEncoderSetCertificateChainMode(
 285     CMSEncoderRef                       cmsEncoder,
 286     CMSCertificateChainMode     chainMode)
 287     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
 288
 289 /*
 290  * Obtain indication of which signer certs are to be included
 291  * in a signed CMS message.
 292  */
 293 OSStatus CMSEncoderGetCertificateChainMode(
 294     CMSEncoderRef                       cmsEncoder,
 295     CMSCertificateChainMode     *chainModeOut)
 296     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
 297
 298 /*
 299  * Feed content bytes into the encoder.
 300  * Can be called multiple times.
 301  * No 'setter' routines can be called after this function has been called.
 302  */
 303 OSStatus CMSEncoderUpdateContent(
 304     CMSEncoderRef               cmsEncoder,
 305     const void                  *content,
 306     size_t                              contentLen)
 307     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
 308
 309 /*
 310  * Finish encoding the message and obtain the encoded result.
 311  * Caller must CFRelease the result.
 312  */
 313 OSStatus CMSEncoderCopyEncodedContent(
 314     CMSEncoderRef               cmsEncoder,
 315     CFDataRef * __nonnull CF_RETURNS_RETAINED encodedContentOut)        /* RETURNED */
 316     __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_11_0);
 317
 318 /*
 319  * High-level, one-shot encoder function.
 320  *
 321  * Inputs (all except for content optional, though at least one
 322  *         of {signers, recipients} must be non-NULL)
 323  * ------------------------------------------------------------
 324  * signers          : signer identities. Either a SecIdentityRef, or a
 325  *                    CFArray of them.
 326  * recipients       : recipient certificates. Either a SecCertificateRef,
 327  *                    or a CFArray of them.
 328  * eContentTypeOID  : contentType OID for inner EncapsulatedData, e.g.:
 329  *                    CFSTR("1.2.840.113549.1.7.1")
 330  * detachedContent  : when true, do not include the signed data in the message.
 331  * signedAttributes : Specifies which standard signed attributes are to be
 332  *                    included in the message.
 333  * content          : raw content to be signed and/or encrypted.
 334  *
 335  * Output
 336  * ------
 337  * encodedContent   : the result of the encoding.
 338  */
 339 OSStatus CMSEncodeContent(
 340     CFTypeRef __nullable    signers,
 341     CFTypeRef __nullable    recipients,
 342     CFTypeRef __nullable    eContentTypeOID,
 343     Boolean                 detachedContent,
 344     CMSSignedAttributes     signedAttributes,
 345     const void              *content,
 346     size_t                  contentLen,
 347     CFDataRef * __nullable CF_RETURNS_RETAINED encodedContentOut)       /* RETURNED */
 348     __OSX_AVAILABLE_STARTING(__MAC_10_7, __IPHONE_11_0);
 349
 350 #if TIMESTAMPING_SUPOORTED
 351 OSStatus CMSEncoderCopySignerTimestamp(
 352     CMSEncoderRef               cmsEncoder,
 353     size_t                              signerIndex,        /* usually 0 */
 354     CFAbsoluteTime      *timestamp)                     /* RETURNED */
 355     __OSX_AVAILABLE_STARTING(__MAC_10_8, __IPHONE_NA);
 356
 357 OSStatus CMSEncoderCopySignerTimestampWithPolicy(
 358     CMSEncoderRef           cmsEncoder,
 359     CFTypeRef __nullable    timeStampPolicy,
 360     size_t                  signerIndex,        /* usually 0 */
 361     CFAbsoluteTime          *timestamp)                 /* RETURNED */
 362     __OSX_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_NA);
 363
 364 void
 365 CmsMessageSetTSAContext(CMSEncoderRef cmsEncoder, CFTypeRef tsaContext);
 366 #endif
 367
 368 /*
 369  * Obtain the SecCmsMessageRef associated with a CMSEncoderRef. Intended
 370  * to be called after (optionally) setting the encoder's various attributes
 371  * via CMSEncoderAddSigners(), CMSEncoderAddRecipients(), etc. and before
 372  * the first call to CMSEncoderUpdateContent(). The returned SecCmsMessageRef
 373  * will be initialized per the previously specified attributes; the caller
 374  * can manipulate the SecCmsMessageRef prior to proceeding with
 375  * CMSEncoderUpdateContent() calls.
 376  */
 377 OSStatus CMSEncoderGetCmsMessage(
 378     CMSEncoderRef               cmsEncoder,
 379     SecCmsMessageRef _Nullable * _Nonnull cmsMessage);          /* RETURNED */
 380
 381 /*
 382  * Optionally specify a SecCmsEncoderRef to use with a CMSEncoderRef.
 383  * If this is called, it must be called before the first call to
 384  * CMSEncoderUpdateContent(). The CMSEncoderRef takes ownership of the
 385  * incoming SecCmsEncoderRef.
 386  */
 387 OSStatus CMSEncoderSetEncoder(
 388     CMSEncoderRef               cmsEncoder,
 389     SecCmsEncoderRef    encoder);
 390
 391 /*
 392  * Obtain the SecCmsEncoderRef associated with a CMSEncoderRef.
 393  * Returns a NULL SecCmsEncoderRef if neither CMSEncoderSetEncoder nor
 394  * CMSEncoderUpdateContent() has been called.
 395  * The CMSEncoderRef retains ownership of the SecCmsEncoderRef.
 396  */
 397 OSStatus CMSEncoderGetEncoder(
 398     CMSEncoderRef               cmsEncoder,
 399     SecCmsEncoderRef    _Nullable * _Nonnull  encoder);                 /* RETURNED */
 400
 401 /*
 402  * Set the signing time for a CMSEncoder.
 403  * This is only used if the kCMSAttrSigningTime attribute is included.
 404  */
 405 OSStatus CMSEncoderSetSigningTime(
 406     CMSEncoderRef               cmsEncoder,
 407     CFAbsoluteTime              time);
 408
 409 /*
 410  * Set the hash agility attribute for a CMSEncoder.
 411  * This is only used if the kCMSAttrAppleCodesigningHashAgility attribute
 412  * is included.
 413  */
 414 OSStatus CMSEncoderSetAppleCodesigningHashAgility(
 415     CMSEncoderRef   cmsEncoder,
 416     CFDataRef       hashAgilityAttrValue);
 417
 418
 419 CF_ASSUME_NONNULL_END
 420
 421 __END_DECLS
 422
 423 #endif  /* _CMS_ENCODER_H_ */
 424