src/common/crypto.h

   1 /* Copyright (c) 2001, Matej Pfajfar.
   2  * Copyright (c) 2001-2004, Roger Dingledine.
   3  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
   4  * Copyright (c) 2007-2011, The Tor Project, Inc. */
   5 /* See LICENSE for licensing information */
   6
   7 /**
   8  * \file crypto.h
   9  *
  10  * \brief Headers for crypto.c
  11  **/
  12
  13 #ifndef _TOR_CRYPTO_H
  14 #define _TOR_CRYPTO_H
  15
  16 #include <stdio.h>
  17 #include "torint.h"
  18
  19 /** Length of the output of our message digest. */
  20 #define DIGEST_LEN 20
  21 /** Length of the output of our second (improved) message digests.  (For now
  22  * this is just sha256, but any it can be any other 256-byte digest). */
  23 #define DIGEST256_LEN 32
  24 /** Length of our symmetric cipher's keys. */
  25 #define CIPHER_KEY_LEN 16
  26 /** Length of our symmetric cipher's IV. */
  27 #define CIPHER_IV_LEN 16
  28 /** Length of our public keys. */
  29 #define PK_BYTES (1024/8)
  30 /** Length of our DH keys. */
  31 #define DH_BYTES (1024/8)
  32
  33 /** Length of a sha1 message digest when encoded in base64 with trailing =
  34  * signs removed. */
  35 #define BASE64_DIGEST_LEN 27
  36 /** Length of a sha256 message digest when encoded in base64 with trailing =
  37  * signs removed. */
  38 #define BASE64_DIGEST256_LEN 43
  39
  40 /** Constants used to indicate no padding for public-key encryption */
  41 #define PK_NO_PADDING         60000
  42 /** Constants used to indicate PKCS1 padding for public-key encryption */
  43 #define PK_PKCS1_PADDING      60001
  44 /** Constants used to indicate OAEP padding for public-key encryption */
  45 #define PK_PKCS1_OAEP_PADDING 60002
  46
  47 /** Number of bytes added for PKCS1 padding. */
  48 #define PKCS1_PADDING_OVERHEAD 11
  49 /** Number of bytes added for PKCS1-OAEP padding. */
  50 #define PKCS1_OAEP_PADDING_OVERHEAD 42
  51
  52 /** Length of encoded public key fingerprints, including space; but not
  53  * including terminating NUL. */
  54 #define FINGERPRINT_LEN 49
  55 /** Length of hex encoding of SHA1 digest, not including final NUL. */
  56 #define HEX_DIGEST_LEN 40
  57 /** Length of hex encoding of SHA256 digest, not including final NUL. */
  58 #define HEX_DIGEST256_LEN 64
  59
  60 typedef enum {
  61   DIGEST_SHA1 = 0,
  62   DIGEST_SHA256 = 1,
  63 } digest_algorithm_t;
  64 #define  N_DIGEST_ALGORITHMS (DIGEST_SHA256+1)
  65
  66 /** A set of all the digests we know how to compute, taken on a single
  67  * string.  Any digests that are shorter than 256 bits are right-padded
  68  * with 0 bits.
  69  *
  70  * Note that this representation wastes 12 bytes for the SHA1 case, so
  71  * don't use it for anything where we need to allocate a whole bunch at
  72  * once.
  73  **/
  74 typedef struct {
  75   char d[N_DIGEST_ALGORITHMS][DIGEST256_LEN];
  76 } digests_t;
  77
  78 typedef struct crypto_pk_env_t crypto_pk_env_t;
  79 typedef struct crypto_cipher_env_t crypto_cipher_env_t;
  80 typedef struct crypto_digest_env_t crypto_digest_env_t;
  81 typedef struct crypto_dh_env_t crypto_dh_env_t;
  82
  83 /* global state */
  84 int crypto_global_init(int hardwareAccel,
  85                        const char *accelName,
  86                        const char *accelPath);
  87 void crypto_thread_cleanup(void);
  88 int crypto_global_cleanup(void);
  89
  90 /* environment setup */
  91 crypto_pk_env_t *crypto_new_pk_env(void);
  92 void crypto_free_pk_env(crypto_pk_env_t *env);
  93
  94 /* convenience function: wraps crypto_create_crypto_env, set_key, and init. */
  95 crypto_cipher_env_t *crypto_create_init_cipher(const char *key,
  96                                                int encrypt_mode);
  97
  98 crypto_cipher_env_t *crypto_new_cipher_env(void);
  99 void crypto_free_cipher_env(crypto_cipher_env_t *env);
 100
 101 /* public key crypto */
 102 int crypto_pk_generate_key_with_bits(crypto_pk_env_t *env, int bits);
 103 #define crypto_pk_generate_key(env)                     \
 104   crypto_pk_generate_key_with_bits((env), (PK_BYTES*8))
 105
 106 int crypto_pk_read_private_key_from_filename(crypto_pk_env_t *env,
 107                                              const char *keyfile);
 108 int crypto_pk_write_public_key_to_string(crypto_pk_env_t *env,
 109                                          char **dest, size_t *len);
 110 int crypto_pk_write_private_key_to_string(crypto_pk_env_t *env,
 111                                           char **dest, size_t *len);
 112 int crypto_pk_read_public_key_from_string(crypto_pk_env_t *env,
 113                                           const char *src, size_t len);
 114 int crypto_pk_read_private_key_from_string(crypto_pk_env_t *env,
 115                                            const char *s);
 116 int crypto_pk_write_private_key_to_filename(crypto_pk_env_t *env,
 117                                             const char *fname);
 118
 119 int crypto_pk_check_key(crypto_pk_env_t *env);
 120 int crypto_pk_cmp_keys(crypto_pk_env_t *a, crypto_pk_env_t *b);
 121 size_t crypto_pk_keysize(crypto_pk_env_t *env);
 122 crypto_pk_env_t *crypto_pk_dup_key(crypto_pk_env_t *orig);
 123 crypto_pk_env_t *crypto_pk_copy_full(crypto_pk_env_t *orig);
 124 int crypto_pk_key_is_private(const crypto_pk_env_t *key);
 125
 126 int crypto_pk_public_encrypt(crypto_pk_env_t *env, char *to, size_t tolen,
 127                              const char *from, size_t fromlen, int padding);
 128 int crypto_pk_private_decrypt(crypto_pk_env_t *env, char *to, size_t tolen,
 129                               const char *from, size_t fromlen,
 130                               int padding, int warnOnFailure);
 131 int crypto_pk_public_checksig(crypto_pk_env_t *env, char *to, size_t tolen,
 132                               const char *from, size_t fromlen);
 133 int crypto_pk_public_checksig_digest(crypto_pk_env_t *env, const char *data,
 134                                size_t datalen, const char *sig, size_t siglen);
 135 int crypto_pk_private_sign(crypto_pk_env_t *env, char *to, size_t tolen,
 136                            const char *from, size_t fromlen);
 137 int crypto_pk_private_sign_digest(crypto_pk_env_t *env, char *to, size_t tolen,
 138                                   const char *from, size_t fromlen);
 139 int crypto_pk_public_hybrid_encrypt(crypto_pk_env_t *env, char *to,
 140                                     size_t tolen,
 141                                     const char *from, size_t fromlen,
 142                                     int padding, int force);
 143 int crypto_pk_private_hybrid_decrypt(crypto_pk_env_t *env, char *to,
 144                                      size_t tolen,
 145                                      const char *from, size_t fromlen,
 146                                      int padding, int warnOnFailure);
 147
 148 int crypto_pk_asn1_encode(crypto_pk_env_t *pk, char *dest, size_t dest_len);
 149 crypto_pk_env_t *crypto_pk_asn1_decode(const char *str, size_t len);
 150 int crypto_pk_get_digest(crypto_pk_env_t *pk, char *digest_out);
 151 int crypto_pk_get_fingerprint(crypto_pk_env_t *pk, char *fp_out,int add_space);
 152 int crypto_pk_check_fingerprint_syntax(const char *s);
 153
 154 /* symmetric crypto */
 155 int crypto_cipher_generate_key(crypto_cipher_env_t *env);
 156 void crypto_cipher_set_key(crypto_cipher_env_t *env, const char *key);
 157 void crypto_cipher_generate_iv(char *iv_out);
 158 int crypto_cipher_set_iv(crypto_cipher_env_t *env, const char *iv);
 159 const char *crypto_cipher_get_key(crypto_cipher_env_t *env);
 160 int crypto_cipher_encrypt_init_cipher(crypto_cipher_env_t *env);
 161 int crypto_cipher_decrypt_init_cipher(crypto_cipher_env_t *env);
 162
 163 int crypto_cipher_encrypt(crypto_cipher_env_t *env, char *to,
 164                           const char *from, size_t fromlen);
 165 int crypto_cipher_decrypt(crypto_cipher_env_t *env, char *to,
 166                           const char *from, size_t fromlen);
 167 int crypto_cipher_crypt_inplace(crypto_cipher_env_t *env, char *d, size_t len);
 168
 169 int crypto_cipher_encrypt_with_iv(crypto_cipher_env_t *env,
 170                                   char *to, size_t tolen,
 171                                   const char *from, size_t fromlen);
 172 int crypto_cipher_decrypt_with_iv(crypto_cipher_env_t *env,
 173                                   char *to, size_t tolen,
 174                                   const char *from, size_t fromlen);
 175
 176 /* SHA-1 and other digests. */
 177 int crypto_digest(char *digest, const char *m, size_t len);
 178 int crypto_digest256(char *digest, const char *m, size_t len,
 179                      digest_algorithm_t algorithm);
 180 int crypto_digest_all(digests_t *ds_out, const char *m, size_t len);
 181 const char *crypto_digest_algorithm_get_name(digest_algorithm_t alg);
 182 int crypto_digest_algorithm_parse_name(const char *name);
 183 crypto_digest_env_t *crypto_new_digest_env(void);
 184 crypto_digest_env_t *crypto_new_digest256_env(digest_algorithm_t algorithm);
 185 void crypto_free_digest_env(crypto_digest_env_t *digest);
 186 void crypto_digest_add_bytes(crypto_digest_env_t *digest, const char *data,
 187                              size_t len);
 188 void crypto_digest_get_digest(crypto_digest_env_t *digest,
 189                               char *out, size_t out_len);
 190 crypto_digest_env_t *crypto_digest_dup(const crypto_digest_env_t *digest);
 191 void crypto_digest_assign(crypto_digest_env_t *into,
 192                           const crypto_digest_env_t *from);
 193 void crypto_hmac_sha1(char *hmac_out,
 194                       const char *key, size_t key_len,
 195                       const char *msg, size_t msg_len);
 196
 197 /* Key negotiation */
 198 crypto_dh_env_t *crypto_dh_new(void);
 199 int crypto_dh_get_bytes(crypto_dh_env_t *dh);
 200 int crypto_dh_generate_public(crypto_dh_env_t *dh);
 201 int crypto_dh_get_public(crypto_dh_env_t *dh, char *pubkey_out,
 202                          size_t pubkey_out_len);
 203 ssize_t crypto_dh_compute_secret(int severity, crypto_dh_env_t *dh,
 204                              const char *pubkey, size_t pubkey_len,
 205                              char *secret_out, size_t secret_out_len);
 206 void crypto_dh_free(crypto_dh_env_t *dh);
 207 int crypto_expand_key_material(const char *key_in, size_t in_len,
 208                                char *key_out, size_t key_out_len);
 209
 210 /* random numbers */
 211 int crypto_seed_rng(int startup);
 212 int crypto_rand(char *to, size_t n);
 213 int crypto_rand_int(unsigned int max);
 214 uint64_t crypto_rand_uint64(uint64_t max);
 215 double crypto_rand_double(void);
 216
 217 char *crypto_random_hostname(int min_rand_len, int max_rand_len,
 218                              const char *prefix, const char *suffix);
 219
 220 struct smartlist_t;
 221 void *smartlist_choose(const struct smartlist_t *sl);
 222 void smartlist_shuffle(struct smartlist_t *sl);
 223
 224 int base64_encode(char *dest, size_t destlen, const char *src, size_t srclen);
 225 int base64_decode(char *dest, size_t destlen, const char *src, size_t srclen);
 226 /** Characters that can appear (case-insensitively) in a base-32 encoding. */
 227 #define BASE32_CHARS "abcdefghijklmnopqrstuvwxyz234567"
 228 void base32_encode(char *dest, size_t destlen, const char *src, size_t srclen);
 229 int base32_decode(char *dest, size_t destlen, const char *src, size_t srclen);
 230
 231 int digest_to_base64(char *d64, const char *digest);
 232 int digest_from_base64(char *digest, const char *d64);
 233 int digest256_to_base64(char *d64, const char *digest);
 234 int digest256_from_base64(char *digest, const char *d64);
 235
 236 /** Length of RFC2440-style S2K specifier: the first 8 bytes are a salt, the
 237  * 9th describes how much iteration to do. */
 238 #define S2K_SPECIFIER_LEN 9
 239 void secret_to_key(char *key_out, size_t key_out_len, const char *secret,
 240                    size_t secret_len, const char *s2k_specifier);
 241
 242 #ifdef CRYPTO_PRIVATE
 243 /* Prototypes for private functions only used by tortls.c and crypto.c */
 244 struct rsa_st;
 245 struct evp_pkey_st;
 246 struct dh_st;
 247 struct rsa_st *_crypto_pk_env_get_rsa(crypto_pk_env_t *env);
 248 crypto_pk_env_t *_crypto_new_pk_env_rsa(struct rsa_st *rsa);
 249 crypto_pk_env_t *_crypto_new_pk_env_evp_pkey(struct evp_pkey_st *pkey);
 250 struct evp_pkey_st *_crypto_pk_env_get_evp_pkey(crypto_pk_env_t *env,
 251                                                 int private);
 252 struct dh_st *_crypto_dh_env_get_dh(crypto_dh_env_t *dh);
 253 /* Prototypes for private functions only used by crypto.c and test.c*/
 254 void add_spaces_to_fp(char *out, size_t outlen, const char *in);
 255 #endif
 256
 257 #endif
 258