sec/Security/vmdh.h

   1 /*
   2  *  vmdh.h
   3  *  Security
   4  *
   5  *  Created by Michael Brouwer on 11/7/06.
   6  *  Copyright (c) 2006-2007 Apple Inc. All Rights Reserved.
   7  *
   8  */
   9
  10 /*!
  11         @header vmdh
  12         The functions provided in vmdh.h implement the crypto exchange required
  13     for a Diffie-Hellman voicemail exchange.
  14 */
  15
  16 #ifndef _SECURITY_VMDH_H_
  17 #define _SECURITY_VMDH_H_
  18
  19 #include <stdint.h>
  20 #include <stdbool.h>
  21 #include <sys/types.h>
  22
  23 #ifdef __cplusplus
  24 extern "C" {
  25 #endif
  26
  27 typedef struct vmdh *vmdh_t;
  28
  29 /* Return a newly allocated vmdh object given g, p and the recip of p recip.
  30    The recip and recip_len parameters are constant for a given p.  They are
  31    optional although providing them improves performance.
  32    The caller should call vmdh_destroy once the returned handle is no longer
  33    needed. */
  34 vmdh_t vmdh_create(uint32_t g, const uint8_t *p, size_t p_len,
  35     const uint8_t *recip, size_t recip_len);
  36
  37 /* Generate a dh private/public keypair and return the public key in pub_key.
  38    on input *pub_key_len is the number of bytes available in pub_key, on output
  39    pub_key_len is the number of bytes actually in pub_key.  Returns true on
  40    success and false on failure. */
  41 bool vmdh_generate_key(vmdh_t vmdh, uint8_t *pub_key, size_t *pub_key_len);
  42
  43 /* Given the length of a password return the size of the encrypted password. */
  44 #define vmdh_encpw_len(PWLEN) (((PWLEN) & ~0xf) + 16)
  45
  46 /* Given a vmdh handle and the other parties public key pub_key (of
  47    pub_key_len bytes long), encrypt the password given by pw of pw_len bytes
  48    long and return it in encpw.  On input *enc_pw contains the number of bytes
  49    available in encpw, on output *encpw will contain the actual length of
  50    encpw. */
  51 bool vmdh_encrypt_password(vmdh_t vmdh,
  52         const uint8_t *pub_key, size_t pub_key_len,
  53     const uint8_t *pw, size_t pw_len, uint8_t *encpw, size_t *encpw_len);
  54
  55 /* Destroy a vmdh object created with vmdh_create(). */
  56 void vmdh_destroy(vmdh_t vmdh);
  57
  58 #ifdef __cplusplus
  59 }
  60 #endif
  61
  62 #endif /* _SECURITY_VMDH_H_ */