-struct GSC_KeyExchangeInfo
-{
-
- /**
- * SetKeyMessage to transmit, NULL if we are not currently trying
- * to send one.
- */
- struct SetKeyMessage *skm;
-
- /**
- * Non-NULL if we are currently looking up HELLOs for this peer.
- * for this peer.
- */
- struct GNUNET_PEERINFO_IteratorContext *pitr;
-
- /**
- * Public key of the neighbour, NULL if we don't have it yet.
- */
- struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *public_key;
-
- /**
- * We received a PING message before we got the "public_key"
- * (or the SET_KEY). We keep it here until we have a key
- * to decrypt it. NULL if no PING is pending.
- */
- struct PingMessage *pending_ping;
-
- /**
- * We received a PONG message before we got the "public_key"
- * (or the SET_KEY). We keep it here until we have a key
- * to decrypt it. NULL if no PONG is pending.
- */
- struct PongMessage *pending_pong;
-
- /**
- * Key we use to encrypt our messages for the other peer
- * (initialized by us when we do the handshake).
- */
- struct GNUNET_CRYPTO_AesSessionKey encrypt_key;
-
- /**
- * Key we use to decrypt messages from the other peer
- * (given to us by the other peer during the handshake).
- */
- struct GNUNET_CRYPTO_AesSessionKey decrypt_key;
-
- /**
- * At what time did we generate our encryption key?
- */
- struct GNUNET_TIME_Absolute encrypt_key_created;
-
- /**
- * At what time did the other peer generate the decryption key?
- */
- struct GNUNET_TIME_Absolute decrypt_key_created;
-
- /**
- * At what frequency are we currently re-trying SET_KEY messages?
- */
- struct GNUNET_TIME_Relative set_key_retry_frequency;
-
- /**
- * ID of task used for re-trying SET_KEY and PING message.
- */
- GNUNET_SCHEDULER_TaskIdentifier retry_set_key_task;
-
- /**
- * What was our PING challenge number (for this peer)?
- */
- uint32_t ping_challenge;
-
- /**
- * What is our connection status?
- */
- enum PeerStateMachine status;
-
-};
+/*
+ This file is part of GNUnet.
+ (C) 2009, 2010, 2011 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3, or (at your
+ option) any later version.
+
+ GNUnet is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNUnet; see the file COPYING. If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+*/
+
+/**
+ * @file core/gnunet-service-core_kx.h
+ * @brief code for managing the key exchange (SET_KEY, PING, PONG) with other peers
+ * @author Christian Grothoff
+ */
+#ifndef GNUNET_SERVICE_CORE_KX_H
+#define GNUNET_SERVICE_CORE_KX_H
+
+#include "gnunet_util_lib.h"
+#include "gnunet_transport_service.h"
+
+
+/**
+ * Information about the status of a key exchange with another peer.
+ */
+struct GSC_KeyExchangeInfo;
+
+
+/**
+ * We received a SET_KEY message. Validate and update
+ * our key material and status.
+ *
+ * @param kx key exchange status for the corresponding peer
+ * @param msg the set key message we received
+ */
+void
+GSC_KX_handle_set_key (struct GSC_KeyExchangeInfo *kx,
+ const struct GNUNET_MessageHeader *msg);
+
+
+/**
+ * We received a PING message. Validate and transmit
+ * a PONG message.
+ *
+ * @param kx key exchange status for the corresponding peer
+ * @param msg the encrypted PING message itself
+ */
+void
+GSC_KX_handle_ping (struct GSC_KeyExchangeInfo *kx,
+ const struct GNUNET_MessageHeader *msg);
+
+
+/**
+ * We received a PONG message. Validate and update our status.
+ *
+ * @param kx key exchange status for the corresponding peer
+ * @param msg the encrypted PONG message itself
+ */
+void
+GSC_KX_handle_pong (struct GSC_KeyExchangeInfo *kx,
+ const struct GNUNET_MessageHeader *msg);
+
+
+/**
+ * Encrypt and transmit a message with the given payload.
+ *
+ * @param kx key exchange context
+ * @param bw_in bandwidth limit to transmit to the other peer;
+ * the other peer shall not send us more than the
+ * given rate
+ * @param payload payload of the message
+ * @param payload_size number of bytes in 'payload'
+ */
+void
+GSC_KX_encrypt_and_transmit (struct GSC_KeyExchangeInfo *kx,
+ struct GNUNET_BANDWIDTH_Value32NBO bw_in,
+ const void *payload,
+ size_t payload_size);
+
+
+/**
+ * We received an encrypted message. Decrypt, validate and
+ * pass on to the appropriate clients.
+ *
+ * @param kx key exchange information context
+ * @param msg encrypted message
+ * @param atsi performance data
+ * @param atsi_count number of entries in ats (excluding 0-termination)
+ */
+void
+GSC_KX_handle_encrypted_message (struct GSC_KeyExchangeInfo *kx,
+ const struct GNUNET_MessageHeader *msg,
+ const struct GNUNET_TRANSPORT_ATS_Information *atsi,
+ uint32_t atsi_count);
+
+
+/**
+ * Start the key exchange with the given peer.
+ *
+ * @param pid identity of the peer to do a key exchange with
+ * @return key exchange information context
+ */
+struct GSC_KeyExchangeInfo *
+GSC_KX_start (const struct GNUNET_PeerIdentity *pid);
+
+
+/**
+ * Stop key exchange with the given peer. Clean up key material.
+ *
+ * @param kx key exchange to stop
+ */
+void
+GSC_KX_stop (struct GSC_KeyExchangeInfo *kx);
+
+
+/**
+ * Initialize KX subsystem.
+ *
+ * @return GNUNET_OK on success, GNUNET_SYSERR on failure
+ */
+int
+GSC_KX_init (void);
+
+
+/**
+ * Shutdown KX subsystem.
+ */
+void
+GSC_KX_done (void);
+
+#endif
+/* end of gnunet-service-core_kx.h */