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 2, or (at your
+ 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
#include "gnunet_statistics_service.h"
#include "gnunet_transport_service.h"
+/**
+ * Opaque pointer that plugins can use to distinguish specific
+ * connections to a given peer. Typically used by stateful plugins to
+ * allow the service to refer to specific streams instead of a more
+ * general notion of "some connection" to the given peer. This is
+ * useful since sometimes (i.e. for inbound TCP connections) a
+ * connection may not have an address that can be used for meaningful
+ * distinction between sessions to the same peer.
+ */
+struct Session;
+
+/**
+ * Every 'struct Session' must begin with this header.
+ */
+struct SessionHeader
+{
+
+ /**
+ * Cached signature for PONG generation for the session. Do not use
+ * in the plugin!
+ */
+ struct GNUNET_CRYPTO_RsaSignature pong_signature;
+
+ /**
+ * Expiration time for signature. Do not use in the plugin!
+ */
+ struct GNUNET_TIME_Absolute pong_sig_expires;
+
+};
+
+/**
+ * Function that will be called whenever the plugin internally
+ * cleans up a session pointer and hence the service needs to
+ * discard all of those sessions as well. Plugins that do not
+ * use sessions can simply omit calling this function and always
+ * use NULL wherever a session pointer is needed.
+ *
+ * @param cls closure
+ * @param peer which peer was the session for
+ * @param session which session is being destoyed
+ */
+typedef void (*GNUNET_TRANSPORT_SessionEnd) (void *cls,
+ const struct GNUNET_PeerIdentity *peer,
+ struct Session *session);
+
/**
* Function called by the transport for each received message.
* @param cls closure
* @param peer (claimed) identity of the other peer
* @param message the message, NULL if we only care about
- * learning about the delay until we should receive again
+ * learning about the delay until we should receive again -- FIXME!
* @param distance in overlay hops; use 1 unless DV (or 0 if message == NULL)
- * @param sender_address binary address of the sender (if observed)
+ * @param session identifier used for this session (NULL for plugins
+ * that do not offer bi-directional communication to the sender
+ * using the same "connection")
+ * @param sender_address binary address of the sender (if we established the
+ * connection or are otherwise sure of it; should be NULL
+ * for inbound TCP/UDP connections since it it not clear
+ * that we could establish ourselves a connection to that
+ * IP address and get the same system)
* @param sender_address_len number of bytes in sender_address
* @return how long the plugin should wait until receiving more data
* (plugins that do not support this, can ignore the return value)
GNUNET_MessageHeader *
message,
uint32_t distance,
+ struct Session *session,
const char *sender_address,
- size_t sender_address_len);
+ uint16_t sender_address_len);
/**
typedef void (*GNUNET_TRANSPORT_AddressNotification) (void *cls,
const char *name,
const void *addr,
- size_t addrlen,
+ uint16_t addrlen,
struct
GNUNET_TIME_Relative
expires);
*/
GNUNET_TRANSPORT_TrafficReport traffic_report;
+ /**
+ * Function that must be called by the plugin when a non-NULL
+ * session handle stops being valid (is destroyed).
+ */
+ GNUNET_TRANSPORT_SessionEnd session_end;
+
/**
* What is the maximum number of connections that this transport
* should allow? Transports that do not have sessions (such as
* require plugins to discard the message after the timeout,
* just advisory for the desired delay; most plugins will ignore
* this as well)
+ * @param session which session must be used (or NULL for "any")
* @param addr the address to use (can be NULL if the plugin
* is "on its own" (i.e. re-use existing TCP connection))
* @param addrlen length of the address in bytes
* @param force_address GNUNET_YES if the plugin MUST use the given address,
- * otherwise the plugin may use other addresses or
- * existing connections (if available)
+ * GNUNET_NO means the plugin may use any other address and
+ * GNUNET_SYSERR means that only reliable existing
+ * bi-directional connections should be used (regardless
+ * of address)
* @param cont continuation to call once the message has
* been transmitted (or if the transport is ready
* for the next transmission call; or if the
size_t msgbuf_size,
uint32_t priority,
struct GNUNET_TIME_Relative timeout,
+ struct Session *session,
const void *addr,
size_t addrlen,
int force_address,
* plugin. Check that this could be a valid address. This function
* is not expected to 'validate' the address in the sense of trying to
* connect to it but simply to see if the binary format is technically
- * legal for establishing a connection.
+ * legal for establishing a connection to this peer (and make sure that
+ * the address really corresponds to our network connection/settings
+ * and not some potential man-in-the-middle).
*
- * @param addr pointer to the address, may be modified (slightly)
+ * @param addr pointer to the address
* @param addrlen length of addr
* @return GNUNET_OK if this is a plausible address for this peer
* and transport, GNUNET_SYSERR if not
*/
typedef int
- (*GNUNET_TRANSPORT_CheckAddress) (void *cls,
- void *addr, size_t addrlen);
+(*GNUNET_TRANSPORT_CheckAddress) (void *cls,
+ const void *addr, size_t addrlen);
+
+
+/**
+ * Function called for a quick conversion of the binary address to
+ * a numeric address. Note that the caller must not free the
+ * address and that the next call to this function is allowed
+ * to override the address again.
+ *
+ * @param cls closure
+ * @param addr binary address
+ * @param addr_len length of the address
+ * @return string representing the same address
+ */
+typedef const char* (*GNUNET_TRANSPORT_AddressToString) (void *cls,
+ const void *addr,
+ size_t addrlen);
+
/**
* Each plugin is required to return a pointer to a struct of this
/**
* Function that the transport service will use to transmit data to
- * another peer. May be null for plugins that only support
+ * another peer. May be NULL for plugins that only support
* receiving data. After this call, the plugin call the specified
* continuation with success or error before notifying us about the
* target having disconnected.
/**
* Function that will be called to check if a binary address
- * for this plugin is well-formed. If clearly needed, patch
- * up information such as port numbers.
+ * for this plugin is well-formed and corresponds to an
+ * address for THIS peer (as per our configuration). Naturally,
+ * if absolutely necessary, plugins can be a bit conservative in
+ * their answer, but in general plugins should make sure that the
+ * address does not redirect traffic to a 3rd party that might
+ * try to man-in-the-middle our traffic.
*/
GNUNET_TRANSPORT_CheckAddress check_address;
+ /**
+ * Function that will be called to convert a binary address
+ * to a string (numeric conversion only).
+ */
+ GNUNET_TRANSPORT_AddressToString address_to_string;
};
projects / oweals / gnunet.git / blobdiff