libsecurity_smime/lib/SecCmsMessage.h

   1 /*
   2  *  Copyright (c) 2004,2008,2010 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     @header SecCmsMessage.h
  26     @Copyright (c) 2004,2008,2010 Apple Inc. All Rights Reserved.
  27
  28     @availability 10.4 and later
  29     @abstract CMS message object interfaces
  30     @abstract Interfaces of the CMS implementation.
  31     @discussion A SecCmsMessage represent a Cryptographic Message
  32                 Syntax (CMS) object as described in rfc3369.
  33                 It can be encoded using a SecCmsEncoder into BER
  34                 data or obtained from a SecCmsDecoder and examined
  35                 using the functions below.
  36  */
  37
  38 #ifndef _SECURITY_SECCMSMESSAGE_H_
  39 #define _SECURITY_SECCMSMESSAGE_H_  1
  40
  41 #include <Security/SecCmsBase.h>
  42
  43
  44 #if defined(__cplusplus)
  45 extern "C" {
  46 #endif
  47
  48
  49 /*!
  50     @function
  51     @abstract Create a CMS message object.
  52     @result A pointer to a newly created SecCmsMessage.  When finished using
  53         this the caller should call SecCmsMessageDestroy().  On failure
  54         returns NULL.  In this case call PR_GetError() to find out what went
  55         wrong.
  56  */
  57 extern SecCmsMessageRef
  58 SecCmsMessageCreate(void);
  59
  60 /*!
  61     @function
  62     @abstract Destroy a CMS message and all of its sub-pieces.
  63     @param cmsg Pointer to a SecCmsMessage object.
  64  */
  65 extern void
  66 SecCmsMessageDestroy(SecCmsMessageRef cmsg);
  67
  68 /*!
  69     @function
  70     @abstract Return a copy of the given message.
  71     @discussion  The copy may be virtual or may be real -- either way, the
  72         result needs to be passed to SecCmsMessageDestroy later (as does the
  73         original).
  74     @param cmsg Pointer to a SecCmsMessage object.
  75  */
  76 extern SecCmsMessageRef
  77 SecCmsMessageCopy(SecCmsMessageRef cmsg);
  78
  79 /*!
  80     @function
  81     @abstract Return a pointer to the top level contentInfo.
  82  */
  83 extern SecCmsContentInfoRef
  84 SecCmsMessageGetContentInfo(SecCmsMessageRef cmsg);
  85
  86 /*!
  87     @function
  88     @abstract Return a pointer to the actual content.
  89     @discussion In the case of those types which are encrypted, this returns the *plain* content.
  90                 In case of nested contentInfos, this descends and retrieves the innermost content.
  91  */
  92 extern const SecAsn1Item *
  93 SecCmsMessageGetContent(SecCmsMessageRef cmsg);
  94
  95 /*!
  96     @function
  97     @abstract Count number of levels of CMS content objects in this message.
  98     @discussion CMS data content objects do not count.
  99  */
 100 extern int
 101 SecCmsMessageContentLevelCount(SecCmsMessageRef cmsg);
 102
 103 /*!
 104     @function
 105     @abstract Find content level #n.
 106     @discussion CMS data content objects do not count.
 107  */
 108 extern SecCmsContentInfoRef
 109 SecCmsMessageContentLevel(SecCmsMessageRef cmsg, int n);
 110
 111 /*!
 112     @function
 113     @abstract See if message contains certs along the way.
 114  */
 115 extern Boolean
 116 SecCmsMessageContainsCertsOrCrls(SecCmsMessageRef cmsg);
 117
 118 /*!
 119     @function
 120     @abstract See if message contains a encrypted submessage.
 121  */
 122 extern Boolean
 123 SecCmsMessageIsEncrypted(SecCmsMessageRef cmsg);
 124
 125 /*!
 126     @function
 127     @abstract See if message contains a signed submessage
 128     @discussion If the CMS message has a SignedData with a signature (not just a SignedData)
 129                 return true; false otherwise.  This can/should be called before calling
 130                 VerifySignature, which will always indicate failure if no signature is
 131                 present, but that does not mean there even was a signature!
 132                 Note that the content itself can be empty (detached content was sent
 133                 another way); it is the presence of the signature that matters.
 134  */
 135 extern Boolean
 136 SecCmsMessageIsSigned(SecCmsMessageRef cmsg);
 137
 138 /*!
 139     @function
 140     @abstract See if content is empty.
 141     @result Returns PR_TRUE is innermost content length is < minLen
 142     @discussion XXX need the encrypted content length (why?)
 143  */
 144 extern Boolean
 145 SecCmsMessageIsContentEmpty(SecCmsMessageRef cmsg, unsigned int minLen);
 146
 147
 148 #if defined(__cplusplus)
 149 }
 150 #endif
 151
 152 #endif /* _SECURITY_SECCMSMESSAGE_H_ */