Update year in copyright headers.

[paraslash.git] / crypt.h

diff --git a/crypt.h b/crypt.h
index 4696ee4a118c5791cfa40ae5cef2c4eb634807ef..9be7a23e6da4d6d1796d4d98da7d8280152c6c2a 100644 (file)
--- a/crypt.h
+++ b/crypt.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2005-2011 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -7,13 +7,14 @@
 /** \file crypt.h Public crypto interface. */
 
 
-/** \cond used to distinguish between loading of private/public key */
+/* These are used to distinguish between loading of private/public key. */
+
+/** The key to load is a public key. */
 #define LOAD_PUBLIC_KEY 0
+/** The key to load is a private key. */
 #define LOAD_PRIVATE_KEY 1
+/** The size of the challenge sent to the client. */
 #define CHALLENGE_SIZE 64
-/** \endcond **/
-
-/* asymetric (public key) crypto */
 
 /** Opaque structure for public and private keys. */
 struct asymmetric_key;
@@ -122,88 +123,53 @@ struct stream_cipher_context {
  *
  * \param data The key.
  * \param len The size of the key.
+ * \param use_aes True: Use the aes_ctr128 stream cipher, false: Use RC4.
  *
  * \return A new stream cipher structure.
  */
-struct stream_cipher *sc_new(const unsigned char *data, int len);
+struct stream_cipher *sc_new(const unsigned char *data, int len,
+               bool use_aes);
 
 /**
- * Deallocate a stream cipher structure.
+ * Encrypt or decrypt a buffer using a stream cipher.
  *
- * \param sc A stream cipher previously obtained by sc_new().
- */
-void sc_free(struct stream_cipher *sc);
-
-/**
- * Encrypt and send a buffer.
+ * \param sc Crypto key.
+ * \param src The source buffer and length.
+ * \param dst The destination buffer and length, filled out by the function.
  *
- * \param scc The context.
- * \param buf The buffer to send.
- * \param len The size of \a buf in bytes.
- *
- * \return The return value of the underyling call to write_all().
- *
- * \sa \ref write_all(), RC4(3).
+ * It is up to the implementation to decide whether the crypt operation is
+ * performed in place. The caller can tell by looking if the buffers given by
+ * \a src and \a dst coincide after the call. If (and only if) the crypt
+ * operation was not performed in place, the function allocated a new buffer
+ * for the result, so dst->iov_base is different from src->iov_base. In this
+ * case, the destination buffer must be freed by the caller when it is no
+ * longer needed.
  */
-int sc_send_bin_buffer(struct stream_cipher_context *scc, char *buf,
-               size_t len);
+void sc_crypt(struct stream_cipher *sc, struct iovec *src, struct iovec *dst);
 
 /**
- * Encrypt and send a \p NULL-terminated buffer.
+ * Wrapper for \ref sc_crypt() that can be used as a sideband transformation.
  *
- * \param scc The context.
- * \param buf The buffer to send.
- *
- * \return The return value of the underyling call to sc_send_bin_buffer().
+ * \param src Passed verbatim to \ref sc_crypt().
+ * \param dst Passed verbatim to \ref sc_crypt().
+ * \param trafo_context Must point to an initialized stream cipher.
  */
-int sc_send_buffer(struct stream_cipher_context *scc, char *buf);
+_static_inline_ void sc_trafo(struct iovec *src, struct iovec *dst,
+               void *trafo_context)
+{
+       sc_crypt(trafo_context, src, dst);
+}
 
 /**
- * Format, encrypt and send a buffer.
- *
- * \param scc The context.
- * \param fmt A format string.
- *
- * \return The return value of the underyling call to sc_send_buffer().
- */
-__printf_2_3 int sc_send_va_buffer(struct stream_cipher_context *scc,
-               const char *fmt, ...);
-
-/**
- * Receive a buffer and decrypt it.
- *
- * \param scc The context.
- * \param buf The buffer to write the decrypted data to.
- * \param size The size of \a buf.
- *
- * \return The number of bytes received on success, negative on errors, zero if
- * the peer has performed an orderly shutdown.
- *
- * \sa recv(2), RC4(3).
- */
-int sc_recv_bin_buffer(struct stream_cipher_context *scc, char *buf,
-               size_t size);
-
-/**
- * Receive a buffer, decrypt it and write terminating NULL byte.
- *
- * \param scc The context.
- * \param buf The buffer to write the decrypted data to.
- * \param size The size of \a buf.
- *
- * Read at most \a size - 1 bytes from file descriptor given by \a scc, decrypt
- * the received data and write a NULL byte at the end of the decrypted data.
+ * Deallocate a stream cipher structure.
  *
- * \return The return value of the underlying call to \ref
- * sc_recv_bin_buffer().
+ * \param sc A stream cipher previously obtained by sc_new().
  */
-int sc_recv_buffer(struct stream_cipher_context *scc, char *buf, size_t size);
-
+void sc_free(struct stream_cipher *sc);
 
 /** Size of the hash value in bytes. */
 #define HASH_SIZE 20
 
-
 /**
  * Compute the hash of the given input data.
  *