src/common/crypto.h

   1 /* Copyright 2001,2002,2003 Roger Dingledine, Matej Pfajfar. */
   2 /* See LICENSE for licensing information */
   3 /* $Id$ */
   4
   5 /**
   6  * \file crypto.h
   7  *
   8  * \brief Headers for low-level cryptographic functions.
   9  **/
  10
  11 #ifndef __CRYPTO_H
  12 #define __CRYPTO_H
  13 #define CRYPTO_H_ID "$Id$"
  14
  15 #include <stdio.h>
  16
  17 /** Length of the output of our message digest. */
  18 #define DIGEST_LEN 20
  19 /** Length of our symmetric cipher's keys. */
  20 #define CIPHER_KEY_LEN 16
  21 /** Length of our public keys. */
  22 #define PK_BYTES (1024/8)
  23 /** Length of our DH keys. */
  24 #define DH_BYTES (1024/8)
  25
  26 /** Constants used to indicate no padding for public-key encryption */
  27 #define PK_NO_PADDING         60000
  28 /** Constants used to indicate PKCS1 padding for public-key encryption */
  29 #define PK_PKCS1_PADDING      60001
  30 /** Constants used to indicate OAEP padding for public-key encryption */
  31 #define PK_PKCS1_OAEP_PADDING 60002
  32
  33 /** Number of bytes added for PKCS1 padding. */
  34 #define PKCS1_PADDING_OVERHEAD 11
  35 /** Number of bytes added for PKCS1-OAEP padding. */
  36 #define PKCS1_OAEP_PADDING_OVERHEAD 42
  37
  38 /** Length of encoded public key fingerprints, including space; but not
  39  * including terminating NUL. */
  40 #define FINGERPRINT_LEN 49
  41 /** Length of hex encoding of SHA1 digest, not including final NUL. */
  42 #define HEX_DIGEST_LEN 40
  43
  44 typedef struct crypto_pk_env_t crypto_pk_env_t;
  45 typedef struct crypto_cipher_env_t crypto_cipher_env_t;
  46 typedef struct crypto_digest_env_t crypto_digest_env_t;
  47 typedef struct crypto_dh_env_t crypto_dh_env_t;
  48
  49 /* global state */
  50 int crypto_global_init(void);
  51 int crypto_global_cleanup(void);
  52
  53 /* environment setup */
  54 crypto_pk_env_t *crypto_new_pk_env(void);
  55 void crypto_free_pk_env(crypto_pk_env_t *env);
  56
  57 /* convenience function: wraps crypto_create_crypto_env, set_key, and init. */
  58 crypto_cipher_env_t *crypto_create_init_cipher(const char *key, int encrypt_mode);
  59
  60 crypto_cipher_env_t *crypto_new_cipher_env(void);
  61 void crypto_free_cipher_env(crypto_cipher_env_t *env);
  62
  63 /* public key crypto */
  64 int crypto_pk_generate_key(crypto_pk_env_t *env);
  65
  66 int crypto_pk_read_private_key_from_filename(crypto_pk_env_t *env, const char *keyfile);
  67 int crypto_pk_write_public_key_to_string(crypto_pk_env_t *env, char **dest, size_t *len);
  68 int crypto_pk_read_public_key_from_string(crypto_pk_env_t *env, const char *src, size_t len);
  69 int crypto_pk_write_private_key_to_filename(crypto_pk_env_t *env, const char *fname);
  70 int crypto_pk_DER64_encode_public_key(crypto_pk_env_t *env, char **dest);
  71 crypto_pk_env_t *crypto_pk_DER64_decode_public_key(const char *in);
  72
  73 int crypto_pk_check_key(crypto_pk_env_t *env);
  74 int crypto_pk_cmp_keys(crypto_pk_env_t *a, crypto_pk_env_t *b);
  75 int crypto_pk_keysize(crypto_pk_env_t *env);
  76 crypto_pk_env_t *crypto_pk_dup_key(crypto_pk_env_t *orig);
  77
  78 int crypto_pk_public_encrypt(crypto_pk_env_t *env, unsigned char *to,
  79                              const unsigned char *from, int fromlen, int padding);
  80 int crypto_pk_private_decrypt(crypto_pk_env_t *env, unsigned char *to,
  81                               const unsigned char *from, int fromlen,
  82                               int padding, int warnOnFailure);
  83 int crypto_pk_public_checksig(crypto_pk_env_t *env, unsigned char *to,
  84                               const unsigned char *from, int fromlen);
  85 int crypto_pk_public_checksig_digest(crypto_pk_env_t *env, const unsigned char *data,
  86                                      int datalen, const unsigned char *sig, int siglen);
  87 int crypto_pk_private_sign(crypto_pk_env_t *env, unsigned char *to,
  88                            const unsigned char *from, int fromlen);
  89 int crypto_pk_private_sign_digest(crypto_pk_env_t *env, unsigned char *to,
  90                                   const unsigned char *from, int fromlen);
  91 int crypto_pk_public_hybrid_encrypt(crypto_pk_env_t *env, unsigned char *to,
  92                                     const unsigned char *from, int fromlen,
  93                                     int padding, int force);
  94 int crypto_pk_private_hybrid_decrypt(crypto_pk_env_t *env, unsigned char *to,
  95                                      const unsigned char *from, int fromlen,
  96                                      int padding, int warnOnFailure);
  97
  98 int crypto_pk_asn1_encode(crypto_pk_env_t *pk, char *dest, int dest_len);
  99 crypto_pk_env_t *crypto_pk_asn1_decode(const char *str, int len);
 100 int crypto_pk_get_digest(crypto_pk_env_t *pk, char *digest_out);
 101 int crypto_pk_get_fingerprint(crypto_pk_env_t *pk, char *fp_out,int add_space);
 102 int crypto_pk_check_fingerprint_syntax(const char *s);
 103
 104 /* symmetric crypto */
 105 int crypto_cipher_generate_key(crypto_cipher_env_t *env);
 106 int crypto_cipher_set_key(crypto_cipher_env_t *env, const unsigned char *key);
 107 const unsigned char *crypto_cipher_get_key(crypto_cipher_env_t *env);
 108 int crypto_cipher_encrypt_init_cipher(crypto_cipher_env_t *env);
 109 int crypto_cipher_decrypt_init_cipher(crypto_cipher_env_t *env);
 110
 111 int crypto_cipher_encrypt(crypto_cipher_env_t *env, unsigned char *to,
 112                           const unsigned char *from, unsigned int fromlen);
 113 int crypto_cipher_decrypt(crypto_cipher_env_t *env, unsigned char *to,
 114                           const unsigned char *from, unsigned int fromlen);
 115
 116 /* only implemented for CRYPTO_CIPHER_AES_CTR */
 117 int crypto_cipher_rewind(crypto_cipher_env_t *env, long delta);
 118 int crypto_cipher_advance(crypto_cipher_env_t *env, long delta);
 119
 120 /* SHA-1 */
 121 int crypto_digest(unsigned char *digest, const unsigned char *m, int len);
 122 crypto_digest_env_t *crypto_new_digest_env(void);
 123 void crypto_free_digest_env(crypto_digest_env_t *digest);
 124 void crypto_digest_add_bytes(crypto_digest_env_t *digest, const char *data,
 125                              size_t len);
 126 void crypto_digest_get_digest(crypto_digest_env_t *digest,
 127                               char *out, size_t out_len);
 128 crypto_digest_env_t *crypto_digest_dup(const crypto_digest_env_t *digest);
 129 void crypto_digest_assign(crypto_digest_env_t *into,
 130                           const crypto_digest_env_t *from);
 131
 132 /* Key negotiation */
 133 crypto_dh_env_t *crypto_dh_new(void);
 134 int crypto_dh_get_bytes(crypto_dh_env_t *dh);
 135 int crypto_dh_generate_public(crypto_dh_env_t *dh);
 136 int crypto_dh_get_public(crypto_dh_env_t *dh, char *pubkey_out,
 137                          size_t pubkey_out_len);
 138 int crypto_dh_compute_secret(crypto_dh_env_t *dh,
 139                              const char *pubkey, size_t pubkey_len,
 140                              char *secret_out, size_t secret_out_len);
 141 void crypto_dh_free(crypto_dh_env_t *dh);
 142
 143 /* random numbers */
 144 int crypto_seed_rng(void);
 145 int crypto_rand(unsigned char *to, unsigned int n);
 146 void crypto_pseudo_rand(unsigned char *to, unsigned int n);
 147 int crypto_pseudo_rand_int(unsigned int max);
 148
 149 struct smartlist_t;
 150 void *smartlist_choose(const struct smartlist_t *sl);
 151
 152 int base64_encode(char *dest, size_t destlen, const char *src, size_t srclen);
 153 int base64_decode(char *dest, size_t destlen, const char *src, size_t srclen);
 154 #define BASE32_CHARS "abcdefghijklmnopqrstuvwxyz234567"
 155 void base32_encode(char *dest, size_t destlen, const char *src, size_t srclen);
 156
 157 #define S2K_SPECIFIER_LEN 9
 158 void secret_to_key(char *key_out, size_t key_out_len, const char *secret,
 159                    size_t secret_len, const char *s2k_specifier);
 160
 161 #endif
 162