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
39extern "C" {
40#endif
41
42typedef 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. */
49vmdh_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. */
56bool 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. */
66bool 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(). */
71void vmdh_destroy(vmdh_t vmdh);
72
73#ifdef __cplusplus
74}
75#endif
76
77#endif /* _SECURITY_VMDH_H_ */
78