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
* Note that the destructors of transport plugins will
* be given the value returned by the constructor
* and is expected to return a NULL pointer.
- *
- * TODO:
- * - consider moving DATA message (latency measurement)
- * to service; avoids encapsulation overheads and
- * would enable latency measurements for non-bidi
- * transports.
- * -
- *
* @author Christian Grothoff
*/
#ifndef PLUGIN_TRANSPORT_H
#include "gnunet_configuration_lib.h"
#include "gnunet_scheduler_lib.h"
+#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.
* message to signal that the other peer disconnected.
*
* @param cls closure
- * @param distance in overlay hops; use 1 unless DV
- * @param sender_address binary address of the sender (if observed)
- * @param sender_address_len number of bytes in sender_address
* @param peer (claimed) identity of the other peer
- * @param message the message, NULL if peer was disconnected
+ * @param message the message, NULL if we only care about
+ * 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 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)
*/
-typedef void (*GNUNET_TRANSPORT_PluginReceiveCallback) (void *cls,
- unsigned int distance,
- const char *sender_address,
- size_t sender_address_len,
- const struct
- GNUNET_PeerIdentity *
- peer,
- const struct
- GNUNET_MessageHeader *
- message);
-
+typedef struct GNUNET_TIME_Relative (*GNUNET_TRANSPORT_PluginReceiveCallback) (void *cls,
+ const struct
+ GNUNET_PeerIdentity *
+ peer,
+ const struct
+ GNUNET_MessageHeader *
+ message,
+ uint32_t distance,
+ struct Session *session,
+ const char *sender_address,
+ 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);
+/**
+ * Function that will be called whenever the plugin receives data over
+ * the network and wants to determine how long it should wait until
+ * the next time it reads from the given peer. Note that some plugins
+ * (such as UDP) may not be able to wait (for a particular peer), so
+ * the waiting part is optional. Plugins that can wait should call
+ * this function, sleep the given amount of time, and call it again
+ * (with zero bytes read) UNTIL it returns zero and only then read.
+ *
+ * @param cls closure
+ * @param peer which peer did we read data from
+ * @param amount_recved number of bytes read (can be zero)
+ * @return how long to wait until reading more from this peer
+ * (to enforce inbound quotas)
+ */
+typedef struct GNUNET_TIME_Relative (*GNUNET_TRANSPORT_TrafficReport) (void *cls,
+ const struct
+ GNUNET_PeerIdentity *peer,
+ size_t amount_recved);
+
+
/**
* The transport service will pass a pointer to a struct
* of this type as the first and only argument to the
*/
const struct GNUNET_PeerIdentity *my_identity;
+ /**
+ * Pointer (!) to our HELLO message. Note that the address
+ * referred to "*our_hello" might change over time.
+ */
+ struct GNUNET_HELLO_Message *const*our_hello;
+
/**
* Closure for the various callbacks.
*/
void *cls;
+ /**
+ * Handle for reporting statistics.
+ */
+ struct GNUNET_STATISTICS_Handle *stats;
+
/**
* Function that should be called by the transport plugin
* whenever a message is received.
GNUNET_TRANSPORT_AddressNotification notify_address;
/**
- * What is the default quota (in terms of incoming bytes per
- * ms) for new connections?
+ * Inform service about traffic received, get information
+ * about when we might be willing to receive more.
+ */
+ GNUNET_TRANSPORT_TrafficReport traffic_report;
+
+ /**
+ * Function that must be called by the plugin when a non-NULL
+ * session handle stops being valid (is destroyed).
*/
- uint32_t default_quota_in;
+ GNUNET_TRANSPORT_SessionEnd session_end;
/**
* What is the maximum number of connections that this transport
*
* @param cls closure
* @param target who should receive this message
- * @param msg the message to transmit
+ * @param msgbuf the message to transmit
+ * @param msgbuf_size number of bytes in 'msgbuf'
* @param priority how important is the message (most plugins will
* ignore message priority and just FIFO)
* @param timeout how long to wait at most for the transmission (does not
* 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
(*GNUNET_TRANSPORT_TransmitFunction) (void *cls,
const struct GNUNET_PeerIdentity *
target,
- const struct GNUNET_MessageHeader *msg,
- unsigned int priority,
+ const char *msgbuf,
+ size_t msgbuf_size,
+ uint32_t priority,
struct GNUNET_TIME_Relative timeout,
+ struct Session *session,
const void *addr,
size_t addrlen,
int force_address,
asc, void *asc_cls);
-/**
- * Set a quota for receiving data from the given peer; this is a
- * per-transport limit. The transport should limit its read/select
- * calls to stay below the quota (in terms of incoming data).
- *
- * @param cls closure
- * @param peer the peer for whom the quota is given
- * @param quota_in quota for receiving/sending data in bytes per ms
- */
-typedef void
- (*GNUNET_TRANSPORT_SetQuota) (void *cls,
- const struct GNUNET_PeerIdentity * target,
- uint32_t quota_in);
-
-
/**
* Another peer has suggested an address for this peer and transport
* 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.
*/
GNUNET_TRANSPORT_AddressPrettyPrinter address_pretty_printer;
- /**
- * Function that the transport service can use to try to enforce a
- * quota for the number of bytes received via this transport.
- * Transports that can not refuse incoming data (such as UDP)
- * are free to ignore these calls.
- */
- GNUNET_TRANSPORT_SetQuota set_receive_quota;
-
/**
* 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;
};