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 void crypto_set_tls_dh_prime(const char *dynamic_dh_modulus_fname);
  95
  96 /* convenience function: wraps crypto_create_crypto_env, set_key, and init. */
  97 crypto_cipher_env_t *crypto_create_init_cipher(const char *key,
  98                                                int encrypt_mode);
  99
 100 crypto_cipher_env_t *crypto_new_cipher_env(void);
 101 void crypto_free_cipher_env(crypto_cipher_env_t *env);
 102
 103 /* public key crypto */
 104 int crypto_pk_generate_key_with_bits(crypto_pk_env_t *env, int bits);
 105 #define crypto_pk_generate_key(env)                     \
 106   crypto_pk_generate_key_with_bits((env), (PK_BYTES*8))
 107
 108 int crypto_pk_read_private_key_from_filename(crypto_pk_env_t *env,
 109                                              const char *keyfile);
 110 int crypto_pk_write_public_key_to_string(crypto_pk_env_t *env,
 111                                          char **dest, size_t *len);
 112 int crypto_pk_write_private_key_to_string(crypto_pk_env_t *env,
 113                                           char **dest, size_t *len);
 114 int crypto_pk_read_public_key_from_string(crypto_pk_env_t *env,
 115                                           const char *src, size_t len);
 116 int crypto_pk_read_private_key_from_string(crypto_pk_env_t *env,
 117                                            const char *s, ssize_t len);
 118 int crypto_pk_write_private_key_to_filename(crypto_pk_env_t *env,
 119                                             const char *fname);
 120
 121 int crypto_pk_check_key(crypto_pk_env_t *env);
 122 int crypto_pk_cmp_keys(crypto_pk_env_t *a, crypto_pk_env_t *b);
 123 size_t crypto_pk_keysize(crypto_pk_env_t *env);
 124 int crypto_pk_num_bits(crypto_pk_env_t *env);
 125 crypto_pk_env_t *crypto_pk_dup_key(crypto_pk_env_t *orig);
 126 crypto_pk_env_t *crypto_pk_copy_full(crypto_pk_env_t *orig);
 127 int crypto_pk_key_is_private(const crypto_pk_env_t *key);
 128 int crypto_pk_public_exponent_ok(crypto_pk_env_t *env);
 129
 130 int crypto_pk_public_encrypt(crypto_pk_env_t *env, char *to, size_t tolen,
 131                              const char *from, size_t fromlen, int padding);
 132 int crypto_pk_private_decrypt(crypto_pk_env_t *env, char *to, size_t tolen,
 133                               const char *from, size_t fromlen,
 134                               int padding, int warnOnFailure);
 135 int crypto_pk_public_checksig(crypto_pk_env_t *env, char *to, size_t tolen,
 136                               const char *from, size_t fromlen);
 137 int crypto_pk_public_checksig_digest(crypto_pk_env_t *env, const char *data,
 138                                size_t datalen, const char *sig, size_t siglen);
 139 int crypto_pk_private_sign(crypto_pk_env_t *env, char *to, size_t tolen,
 140                            const char *from, size_t fromlen);
 141 int crypto_pk_private_sign_digest(crypto_pk_env_t *env, char *to, size_t tolen,
 142                                   const char *from, size_t fromlen);
 143 int crypto_pk_public_hybrid_encrypt(crypto_pk_env_t *env, char *to,
 144                                     size_t tolen,
 145                                     const char *from, size_t fromlen,
 146                                     int padding, int force);
 147 int crypto_pk_private_hybrid_decrypt(crypto_pk_env_t *env, char *to,
 148                                      size_t tolen,
 149                                      const char *from, size_t fromlen,
 150                                      int padding, int warnOnFailure);
 151
 152 int crypto_pk_asn1_encode(crypto_pk_env_t *pk, char *dest, size_t dest_len);
 153 crypto_pk_env_t *crypto_pk_asn1_decode(const char *str, size_t len);
 154 int crypto_pk_get_digest(crypto_pk_env_t *pk, char *digest_out);
 155 int crypto_pk_get_all_digests(crypto_pk_env_t *pk, digests_t *digests_out);
 156 int crypto_pk_get_fingerprint(crypto_pk_env_t *pk, char *fp_out,int add_space);
 157 int crypto_pk_check_fingerprint_syntax(const char *s);
 158
 159 /* symmetric crypto */
 160 int crypto_cipher_generate_key(crypto_cipher_env_t *env);
 161 void crypto_cipher_set_key(crypto_cipher_env_t *env, const char *key);
 162 void crypto_cipher_generate_iv(char *iv_out);
 163 int crypto_cipher_set_iv(crypto_cipher_env_t *env, const char *iv);
 164 const char *crypto_cipher_get_key(crypto_cipher_env_t *env);
 165 int crypto_cipher_encrypt_init_cipher(crypto_cipher_env_t *env);
 166 int crypto_cipher_decrypt_init_cipher(crypto_cipher_env_t *env);
 167
 168 int crypto_cipher_encrypt(crypto_cipher_env_t *env, char *to,
 169                           const char *from, size_t fromlen);
 170 int crypto_cipher_decrypt(crypto_cipher_env_t *env, char *to,
 171                           const char *from, size_t fromlen);
 172 int crypto_cipher_crypt_inplace(crypto_cipher_env_t *env, char *d, size_t len);
 173
 174 int crypto_cipher_encrypt_with_iv(crypto_cipher_env_t *env,
 175                                   char *to, size_t tolen,
 176                                   const char *from, size_t fromlen);
 177 int crypto_cipher_decrypt_with_iv(crypto_cipher_env_t *env,
 178                                   char *to, size_t tolen,
 179                                   const char *from, size_t fromlen);
 180
 181 /* SHA-1 and other digests. */
 182 int crypto_digest(char *digest, const char *m, size_t len);
 183 int crypto_digest256(char *digest, const char *m, size_t len,
 184                      digest_algorithm_t algorithm);
 185 int crypto_digest_all(digests_t *ds_out, const char *m, size_t len);
 186 const char *crypto_digest_algorithm_get_name(digest_algorithm_t alg);
 187 int crypto_digest_algorithm_parse_name(const char *name);
 188 crypto_digest_env_t *crypto_new_digest_env(void);
 189 crypto_digest_env_t *crypto_new_digest256_env(digest_algorithm_t algorithm);
 190 void crypto_free_digest_env(crypto_digest_env_t *digest);
 191 void crypto_digest_add_bytes(crypto_digest_env_t *digest, const char *data,
 192                              size_t len);
 193 void crypto_digest_get_digest(crypto_digest_env_t *digest,
 194                               char *out, size_t out_len);
 195 crypto_digest_env_t *crypto_digest_dup(const crypto_digest_env_t *digest);
 196 void crypto_digest_assign(crypto_digest_env_t *into,
 197                           const crypto_digest_env_t *from);
 198 void crypto_hmac_sha1(char *hmac_out,
 199                       const char *key, size_t key_len,
 200                       const char *msg, size_t msg_len);
 201 void crypto_hmac_sha256(char *hmac_out,
 202                         const char *key, size_t key_len,
 203                         const char *msg, size_t msg_len);
 204
 205 /* Key negotiation */
 206 #define DH_TYPE_CIRCUIT 1
 207 #define DH_TYPE_REND 2
 208 #define DH_TYPE_TLS 3
 209 crypto_dh_env_t *crypto_dh_new(int dh_type);
 210 int crypto_dh_get_bytes(crypto_dh_env_t *dh);
 211 int crypto_dh_generate_public(crypto_dh_env_t *dh);
 212 int crypto_dh_get_public(crypto_dh_env_t *dh, char *pubkey_out,
 213                          size_t pubkey_out_len);
 214 ssize_t crypto_dh_compute_secret(int severity, crypto_dh_env_t *dh,
 215                              const char *pubkey, size_t pubkey_len,
 216                              char *secret_out, size_t secret_out_len);
 217 void crypto_dh_free(crypto_dh_env_t *dh);
 218 int crypto_expand_key_material(const char *key_in, size_t in_len,
 219                                char *key_out, size_t key_out_len);
 220
 221 /* random numbers */
 222 int crypto_seed_rng(int startup);
 223 int crypto_rand(char *to, size_t n);
 224 int crypto_rand_int(unsigned int max);
 225 uint64_t crypto_rand_uint64(uint64_t max);
 226 double crypto_rand_double(void);
 227
 228 char *crypto_random_hostname(int min_rand_len, int max_rand_len,
 229                              const char *prefix, const char *suffix);
 230
 231 struct smartlist_t;
 232 void *smartlist_choose(const struct smartlist_t *sl);
 233 void smartlist_shuffle(struct smartlist_t *sl);
 234
 235 int base64_encode(char *dest, size_t destlen, const char *src, size_t srclen);
 236 int base64_decode(char *dest, size_t destlen, const char *src, size_t srclen);
 237 /** Characters that can appear (case-insensitively) in a base-32 encoding. */
 238 #define BASE32_CHARS "abcdefghijklmnopqrstuvwxyz234567"
 239 void base32_encode(char *dest, size_t destlen, const char *src, size_t srclen);
 240 int base32_decode(char *dest, size_t destlen, const char *src, size_t srclen);
 241
 242 int digest_to_base64(char *d64, const char *digest);
 243 int digest_from_base64(char *digest, const char *d64);
 244 int digest256_to_base64(char *d64, const char *digest);
 245 int digest256_from_base64(char *digest, const char *d64);
 246
 247 /** Length of RFC2440-style S2K specifier: the first 8 bytes are a salt, the
 248  * 9th describes how much iteration to do. */
 249 #define S2K_SPECIFIER_LEN 9
 250 void secret_to_key(char *key_out, size_t key_out_len, const char *secret,
 251                    size_t secret_len, const char *s2k_specifier);
 252
 253 #ifdef CRYPTO_PRIVATE
 254 /* Prototypes for private functions only used by tortls.c, crypto.c, and the
 255  * unit tests. */
 256 struct rsa_st;
 257 struct evp_pkey_st;
 258 struct dh_st;
 259 struct rsa_st *_crypto_pk_env_get_rsa(crypto_pk_env_t *env);
 260 crypto_pk_env_t *_crypto_new_pk_env_rsa(struct rsa_st *rsa);
 261 struct evp_pkey_st *_crypto_pk_env_get_evp_pkey(crypto_pk_env_t *env,
 262                                                 int private);
 263 struct dh_st *_crypto_dh_env_get_dh(crypto_dh_env_t *dh);
 264 /* Prototypes for private functions only used by crypto.c and test.c*/
 265 void add_spaces_to_fp(char *out, size_t outlen, const char *in);
 266 #endif
 267
 268 #endif
 269