release/src/router/dropbear/algo.h

   1 /*
   2  * Dropbear - a SSH2 server
   3  *
   4  * Copyright (c) 2002,2003 Matt Johnston
   5  * All rights reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  20  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  23  * SOFTWARE. */
  24
  25 #ifndef _ALGO_H_
  26
  27 #define _ALGO_H_
  28
  29 #include "includes.h"
  30 #include "buffer.h"
  31
  32 #define DROPBEAR_MODE_UNUSED 0
  33 #define DROPBEAR_MODE_CBC 1
  34 #define DROPBEAR_MODE_CTR 2
  35
  36 struct Algo_Type {
  37
  38         const unsigned char *name; /* identifying name */
  39         char val; /* a value for this cipher, or -1 for invalid */
  40         const void *data; /* algorithm specific data */
  41         char usable; /* whether we can use this algorithm */
  42         const void *mode; /* the mode, currently only used for ciphers,
  43                                                  points to a 'struct dropbear_cipher_mode' */
  44 };
  45
  46 typedef struct Algo_Type algo_type;
  47
  48 /* lists mapping ssh types of algorithms to internal values */
  49 extern algo_type sshkex[];
  50 extern algo_type sshhostkey[];
  51 extern algo_type sshciphers[];
  52 extern algo_type sshhashes[];
  53 extern algo_type ssh_compress[];
  54 extern algo_type ssh_nocompress[];
  55
  56 extern const struct dropbear_cipher dropbear_nocipher;
  57 extern const struct dropbear_cipher_mode dropbear_mode_none;
  58 extern const struct dropbear_hash dropbear_nohash;
  59
  60 struct dropbear_cipher {
  61         const struct ltc_cipher_descriptor *cipherdesc;
  62         const unsigned long keysize;
  63         const unsigned char blocksize;
  64 };
  65
  66 struct dropbear_cipher_mode {
  67         int (*start)(int cipher, const unsigned char *IV,
  68                         const unsigned char *key,
  69                         int keylen, int num_rounds, void *cipher_state);
  70         int (*encrypt)(const unsigned char *pt, unsigned char *ct,
  71                         unsigned long len, void *cipher_state);
  72         int (*decrypt)(const unsigned char *ct, unsigned char *pt,
  73                         unsigned long len, void *cipher_state);
  74 };
  75
  76 struct dropbear_hash {
  77         const struct ltc_hash_descriptor *hash_desc;
  78         const unsigned long keysize;
  79         /* hashsize may be truncated from the size returned by hash_desc,
  80            eg sha1-96 */
  81         const unsigned char hashsize;
  82 };
  83
  84 enum dropbear_kex_mode {
  85         DROPBEAR_KEX_NORMAL_DH,
  86         DROPBEAR_KEX_ECDH,
  87         DROPBEAR_KEX_CURVE25519,
  88 };
  89
  90 struct dropbear_kex {
  91         enum dropbear_kex_mode mode;
  92
  93         /* "normal" DH KEX */
  94         const unsigned char *dh_p_bytes;
  95         const int dh_p_len;
  96
  97         /* elliptic curve DH KEX */
  98 #ifdef DROPBEAR_ECDH
  99         const struct dropbear_ecc_curve *ecc_curve;
 100 #else
 101         const void* dummy;
 102 #endif
 103
 104         /* both */
 105         const struct ltc_hash_descriptor *hash_desc;
 106 };
 107
 108 int have_algo(char* algo, size_t algolen, algo_type algos[]);
 109 void buf_put_algolist(buffer * buf, algo_type localalgos[]);
 110
 111 enum kexguess2_used {
 112         KEXGUESS2_LOOK,
 113         KEXGUESS2_NO,
 114         KEXGUESS2_YES,
 115 };
 116
 117 #define KEXGUESS2_ALGO_NAME "kexguess2@matt.ucc.asn.au"
 118 #define KEXGUESS2_ALGO_ID 99
 119
 120
 121 algo_type * buf_match_algo(buffer* buf, algo_type localalgos[],
 122                 enum kexguess2_used *kexguess2, int *goodguess);
 123
 124 #ifdef ENABLE_USER_ALGO_LIST
 125 int check_user_algos(const char* user_algo_list, algo_type * algos,
 126                 const char *algo_desc);
 127 char * algolist_string(algo_type algos[]);
 128 #endif
 129
 130 enum {
 131         DROPBEAR_COMP_NONE,
 132         DROPBEAR_COMP_ZLIB,
 133         DROPBEAR_COMP_ZLIB_DELAY,
 134 };
 135
 136 #endif /* _ALGO_H_ */