1  /*
 2   * Copyright (c) 2006-2007,2012,2014 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  /*!
26  	@header vmdh
27  	The functions provided in vmdh.h implement the crypto exchange required
28      for a Diffie-Hellman voicemail exchange.
29  */
30  
31  #ifndef _SECURITY_VMDH_H_
32  #define _SECURITY_VMDH_H_
33  
34  #include <stdint.h>
35  #include <stdbool.h>
36  #include <sys/types.h>
37  
38  #ifdef __cplusplus
39  extern "C" {
40  #endif
41  
42  typedef struct vmdh *vmdh_t;
43  
44  /* Return a newly allocated vmdh object given g, p and the recip of p recip.
45     The recip and recip_len parameters are constant for a given p.  They are
46     optional although providing them improves performance.
47     The caller should call vmdh_destroy once the returned handle is no longer
48     needed. */
49  vmdh_t vmdh_create(uint32_t g, const uint8_t *p, size_t p_len,
50      const uint8_t *recip, size_t recip_len);
51  
52  /* Generate a dh private/public keypair and return the public key in pub_key.
53     on input *pub_key_len is the number of bytes available in pub_key, on output
54     pub_key_len is the number of bytes actually in pub_key.  Returns true on
55     success and false on failure. */
56  bool vmdh_generate_key(vmdh_t vmdh, uint8_t *pub_key, size_t *pub_key_len);
57  
58  /* Given the length of a password return the size of the encrypted password. */
59  #define vmdh_encpw_len(PWLEN) (((PWLEN) & ~0xf) + 16)
60  
61  /* Given a vmdh handle and the other parties public key pub_key (of
62     pub_key_len bytes long), encrypt the password given by pw of pw_len bytes
63     long and return it in encpw.  On input *enc_pw contains the number of bytes
64     available in encpw, on output *encpw will contain the actual length of
65     encpw. */ 
66  bool vmdh_encrypt_password(vmdh_t vmdh,
67  	const uint8_t *pub_key, size_t pub_key_len,
68      const uint8_t *pw, size_t pw_len, uint8_t *encpw, size_t *encpw_len);
69  
70  /* Destroy a vmdh object created with vmdh_create(). */
71  void vmdh_destroy(vmdh_t vmdh);
72  
73  #ifdef __cplusplus
74  }
75  #endif
76  
77  #endif /* _SECURITY_VMDH_H_ */