2 * Copyright (C) 2005-2011 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file crypt.h Prototypes for paraslash crypto functions. */
9 /** Opaque structure for public and private keys. */
10 struct asymmetric_key;
12 int pub_encrypt(struct asymmetric_key *pub, unsigned char *inbuf,
13 unsigned len, unsigned char *outbuf);
14 int priv_decrypt(const char *key_file, unsigned char *outbuf,
15 unsigned char *inbuf, int inlen);
16 int get_asymmetric_key(const char *key_file, int private,
17 struct asymmetric_key **result);
18 void free_asymmetric_key(struct asymmetric_key *key);
20 void get_random_bytes_or_die(unsigned char *buf, int num);
21 void init_random_seed_or_die(void);
23 /** Opaque structure for stream cipher crypto. */
26 /** Number of bytes of the session key. */
27 #define SESSION_KEY_LEN 32
30 * Used on the server-side for client-server communication encryption.
32 * The traffic between (the forked child of) para_server and the remote client
33 * process is crypted by a symmetric session key. This structure contains the
34 * keys for the stream cipher and the file descriptor for which these keys
37 struct stream_cipher_context {
38 /** The socket file descriptor. */
40 /** Key used for receiving data. */
41 struct stream_cipher *recv;
42 /** Key used for sending data. */
43 struct stream_cipher *send;
46 struct stream_cipher *sc_new(const unsigned char *data, int len);
47 void sc_free(struct stream_cipher *sc);
49 int sc_send_bin_buffer(struct stream_cipher_context *scc, const char *buf,
51 int sc_send_buffer(struct stream_cipher_context *scc, const char *buf);
52 __printf_2_3 int sc_send_va_buffer(struct stream_cipher_context *scc,
53 const char *fmt, ...);
54 int sc_recv_bin_buffer(struct stream_cipher_context *scc, char *buf,
56 int sc_recv_buffer(struct stream_cipher_context *scc, char *buf, size_t size);
58 /** \cond used to distinguish between loading of private/public key */
59 #define LOAD_PUBLIC_KEY 0
60 #define LOAD_PRIVATE_KEY 1
61 #define CHALLENGE_SIZE 64
64 /** Size of the hash value in bytes. */
67 void hash_function(const char *data, unsigned long len, unsigned char *hash);
72 * \param h1 Pointer to the first hash value.
73 * \param h2 Pointer to the second hash value.
75 * \return 1, -1, or zero, depending on whether \a h1 is greater than,
76 * less than or equal to h2, respectively.
78 _static_inline_ int hash_compare(unsigned char *h1, unsigned char *h2)
82 for (i = 0; i < HASH_SIZE; i++) {
92 * Convert a hash value to ascii format.
94 * \param hash the hash value.
95 * \param asc Result pointer.
97 * \a asc must point to an area of at least 2 * \p HASH_SIZE + 1 bytes which
98 * will be filled by the function with the ascii representation of the hash
99 * value given by \a hash, and a terminating \p NULL byte.
101 _static_inline_ void hash_to_asc(unsigned char *hash, char *asc)
104 const char hexchar[] = "0123456789abcdef";
106 for (i = 0; i < HASH_SIZE; i++) {
107 asc[2 * i] = hexchar[hash[i] >> 4];
108 asc[2 * i + 1] = hexchar[hash[i] & 0xf];
110 asc[2 * HASH_SIZE] = '\0';