stream cipher: Allow in-place encryption.

[paraslash.git] / crypt.h

diff --git a/crypt.h b/crypt.h
index 0e0695e574ecbfcb6dd4c5491fa2f499329a8d14..fc41acf3f04efcedcad75a7a61e9dae3b8dfd6fa 100644 (file)
--- a/crypt.h
+++ b/crypt.h
@@ -4,7 +4,16 @@
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
 
-/** \file crypt.h Prototypes for paraslash crypto functions. */
+/** \file crypt.h Public crypto interface. */
+
+
+/** \cond used to distinguish between loading of private/public key */
+#define LOAD_PUBLIC_KEY 0
+#define LOAD_PRIVATE_KEY 1
+#define CHALLENGE_SIZE 64
+/** \endcond **/
+
+/* asymetric (public key) crypto */
 
 /** Opaque structure for public and private keys. */
 struct asymmetric_key;
@@ -17,17 +26,18 @@ int get_asymmetric_key(const char *key_file, int private,
                struct asymmetric_key **result);
 void free_asymmetric_key(struct asymmetric_key *key);
 
+/* random numbers */
 void get_random_bytes_or_die(unsigned char *buf, int num);
 void init_random_seed_or_die(void);
 
-/** Opaque structure for stream cipher crypto. */
-struct stream_cipher;
+/* stream cipher declarations and prototypes */
 
-/** Number of bytes of the session key. */
+/** Opaque structure for stream ciphers. */
+struct stream_cipher;
+/** Number of bytes of the session key for stream ciphers. */
 #define SESSION_KEY_LEN 32
-
 /**
- * Used on the server-side for client-server communication encryption.
+ * Used for client-server communication encryption.
  *
  * The traffic between (the forked child of) para_server and the remote client
  * process is crypted by a symmetric session key. This structure contains the
@@ -42,21 +52,22 @@ struct stream_cipher_context {
        /** Key used for sending data. */
        struct stream_cipher *send;
 };
-
 struct stream_cipher *sc_new(const unsigned char *data, int len);
 void sc_free(struct stream_cipher *sc);
-
-int sc_send_bin_buffer(struct stream_cipher_context *scc, const char *buf,
+int sc_send_bin_buffer(struct stream_cipher_context *scc, char *buf,
                size_t len);
-int sc_send_buffer(struct stream_cipher_context *scc, const char *buf);
+int sc_send_buffer(struct stream_cipher_context *scc, char *buf);
 __printf_2_3 int sc_send_va_buffer(struct stream_cipher_context *scc,
                const char *fmt, ...);
 int sc_recv_bin_buffer(struct stream_cipher_context *scc, char *buf,
                size_t size);
 int sc_recv_buffer(struct stream_cipher_context *scc, char *buf, size_t size);
 
-/** \cond used to distinguish between loading of private/public key */
-#define LOAD_PUBLIC_KEY 0
-#define LOAD_PRIVATE_KEY 1
-#define CHALLENGE_SIZE 64
-/** \endcond **/
+/* hashing */
+
+/** Size of the hash value in bytes. */
+#define HASH_SIZE 20
+
+void hash_function(const char *data, unsigned long len, unsigned char *hash);
+void hash_to_asc(unsigned char *hash, char *asc);
+int hash_compare(unsigned char *h1, unsigned char *h2);