382 lines
13 KiB
C
382 lines
13 KiB
C
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#include "libp2p/net/stream.h"
|
|
#include "libp2p/routing/dht_protocol.h"
|
|
#include "libp2p/record/message.h"
|
|
#include "libp2p/utils/logger.h"
|
|
#include "libp2p/conn/session.h"
|
|
|
|
|
|
/***
|
|
* This is where kademlia and dht talk to the outside world
|
|
*/
|
|
|
|
|
|
/***
|
|
* Helper method to protobuf a message
|
|
* @param message the message
|
|
* @param buffer where to put the results
|
|
* @param buffer_size the size of the results
|
|
* @returns true(1) on success, false(0) otherwise
|
|
*/
|
|
int libp2p_routing_dht_protobuf_message(struct Libp2pMessage* message, unsigned char** buffer, size_t *buffer_size) {
|
|
*buffer_size = libp2p_message_protobuf_encode_size(message);
|
|
*buffer = malloc(*buffer_size);
|
|
if (!libp2p_message_protobuf_encode(message, *buffer, *buffer_size, buffer_size)) {
|
|
free(*buffer);
|
|
*buffer_size = 0;
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
/**
|
|
* Take existing stream and upgrade to the Kademlia / DHT protocol/codec
|
|
* @param context the context
|
|
* @returns true(1) on success, otherwise false(0)
|
|
*/
|
|
int libp2p_routing_dht_upgrade_stream(struct SessionContext* context) {
|
|
int retVal = 0;
|
|
char* protocol = "/ipfs/kad/1.0.0\n";
|
|
unsigned char* results = NULL;
|
|
size_t results_size = 0;
|
|
if (!context->default_stream->write(context, (unsigned char*)protocol, strlen(protocol)))
|
|
goto exit;
|
|
if (!context->default_stream->read(context, &results, &results_size, 5))
|
|
goto exit;
|
|
if (results_size != strlen(protocol))
|
|
goto exit;
|
|
if (strncmp((char*)results, protocol, results_size) != 0)
|
|
goto exit;
|
|
retVal = 1;
|
|
exit:
|
|
if (results != NULL) {
|
|
free(results);
|
|
results = NULL;
|
|
}
|
|
return retVal;
|
|
}
|
|
|
|
/**
|
|
* Handle a client requesting an upgrade to the DHT protocol
|
|
* @param context the context
|
|
* @returns true(1) on success, otherwise false(0)
|
|
*/
|
|
int libp2p_routing_dht_handshake(struct SessionContext* context) {
|
|
char* protocol = "/ipfs/kad/1.0.0\n";
|
|
return context->default_stream->write(context, (unsigned char*)protocol, strlen(protocol));
|
|
}
|
|
|
|
/**
|
|
* A remote client has requested a ping
|
|
* @param message the message
|
|
* @param buffer where to put the results
|
|
* @param buffer_size the length of the results
|
|
* @returns true(1) on success, false(0) otherwise
|
|
*/
|
|
int libp2p_routing_dht_handle_ping(struct Libp2pMessage* message, unsigned char** buffer, size_t *buffer_size) {
|
|
// just turn message back into a protobuf and send it back...
|
|
return libp2p_routing_dht_protobuf_message(message, buffer, buffer_size);
|
|
}
|
|
|
|
/**
|
|
* See if we have information as to who can provide this item
|
|
* @param session the context
|
|
* @param message the message from the caller, contains a key
|
|
* @param peerstore the list of peers
|
|
* @param providerstore the list of peers that can provide things
|
|
* @returns true(1) on success, false(0) otherwise
|
|
*/
|
|
int libp2p_routing_dht_handle_get_providers(struct SessionContext* session, struct Libp2pMessage* message, struct Peerstore* peerstore,
|
|
struct ProviderStore* providerstore, unsigned char** results, size_t* results_size) {
|
|
unsigned char* peer_id = NULL;
|
|
int peer_id_size = 0;
|
|
|
|
// This shouldn't be needed, but just in case:
|
|
message->provider_peer_head = NULL;
|
|
|
|
// Can I provide it?
|
|
if (libp2p_providerstore_get(providerstore, message->key, message->key_size, &peer_id, &peer_id_size)) {
|
|
libp2p_logger_debug("dht_protocol", "I can provide a provider for this key.\n");
|
|
// we have a peer id, convert it to a peer object
|
|
struct Libp2pPeer* peer = libp2p_peerstore_get_peer(peerstore, peer_id, peer_id_size);
|
|
if (peer != NULL) {
|
|
message->provider_peer_head = libp2p_utils_linked_list_new();
|
|
message->provider_peer_head->item = libp2p_peer_copy(peer);
|
|
}
|
|
} else {
|
|
libp2p_logger_debug("dht_protocol", "I cannot provide a provider for this key.\n");
|
|
}
|
|
free(peer_id);
|
|
// TODO: find closer peers
|
|
/*
|
|
if (message->provider_peer_head == NULL) {
|
|
// Who else can provide it?
|
|
//while ()
|
|
}
|
|
*/
|
|
if (message->provider_peer_head != NULL) {
|
|
libp2p_logger_debug("dht_protocol", "GetProviders: We have a peer. Sending it back\n");
|
|
// protobuf it and send it back
|
|
if (!libp2p_routing_dht_protobuf_message(message, results, results_size)) {
|
|
libp2p_logger_error("dht_protocol", "GetProviders: Error protobufing results\n");
|
|
return 0;
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
/***
|
|
* helper method to get ip multiaddress from peer's linked list
|
|
* @param head linked list of multiaddresses
|
|
* @returns the IP multiaddress in the list, or NULL if none found
|
|
*/
|
|
struct MultiAddress* libp2p_routing_dht_find_peer_ip_multiaddress(struct Libp2pLinkedList* head) {
|
|
struct MultiAddress* out = NULL;
|
|
struct Libp2pLinkedList* current = head;
|
|
while (current != NULL) {
|
|
out = (struct MultiAddress*)current->item;
|
|
if (multiaddress_is_ip(out)) {
|
|
libp2p_logger_debug("dht_protocol", "Found MultiAddress %s\n", out->string);
|
|
break;
|
|
}
|
|
current = current->next;
|
|
}
|
|
if (current == NULL)
|
|
out = NULL;
|
|
return out;
|
|
}
|
|
|
|
/***
|
|
* Remote peer has announced that he can provide a key
|
|
* @param session session context
|
|
* @param message the message
|
|
* @param peerstore the peerstore
|
|
* @param providerstore the providerstore
|
|
* @param result_buffer where to put the result
|
|
* @param result_buffer_size the size of the result buffer
|
|
* @returns true(1) on success, otherwise false(0)
|
|
*/
|
|
int libp2p_routing_dht_handle_add_provider(struct SessionContext* session, struct Libp2pMessage* message,
|
|
struct Peerstore* peerstore, struct ProviderStore* providerstore, unsigned char** result_buffer, size_t* result_buffer_size) {
|
|
int retVal = 0;
|
|
struct Libp2pPeer *peer = NULL;
|
|
|
|
//TODO: verify peer signature
|
|
/*
|
|
if (message->record != NULL && message->record->author != NULL && message->record->author_size > 0
|
|
&& message->key != NULL && message->key_size > 0)
|
|
*/
|
|
|
|
struct Libp2pLinkedList* current = message->provider_peer_head;
|
|
if (current == NULL) {
|
|
libp2p_logger_error("dht_protocol", "Provider has no peer.\n");
|
|
goto exit;
|
|
}
|
|
// there should only be 1 when adding a provider
|
|
if (current != NULL) {
|
|
peer = current->item;
|
|
if (peer == NULL) {
|
|
libp2p_logger_error("dht_protocol", "Message add_provider has no peer\n");
|
|
goto exit;
|
|
}
|
|
struct MultiAddress *peer_ma = libp2p_routing_dht_find_peer_ip_multiaddress(peer->addr_head);
|
|
if (peer_ma == NULL) {
|
|
libp2p_logger_error("dht_protocol", "Peer has no IP MultiAddress.\n");
|
|
goto exit;
|
|
}
|
|
// add what we know to be the ip for this peer
|
|
char *ip;
|
|
char new_string[255];
|
|
multiaddress_get_ip_address(session->default_stream->address, &ip);
|
|
int port = multiaddress_get_ip_port(peer_ma);
|
|
char* peer_id = multiaddress_get_peer_id(peer_ma);
|
|
sprintf(new_string, "/ip4/%s/tcp/%d/ipfs/%s", ip, port, peer_id);
|
|
free(ip);
|
|
free(peer_id);
|
|
struct MultiAddress* new_ma = multiaddress_new_from_string(new_string);
|
|
if (new_ma == NULL)
|
|
goto exit;
|
|
libp2p_logger_debug("dht_protocol", "New MultiAddress made with %s.\n", new_string);
|
|
// TODO: See if the sender is who he says he is
|
|
// set it as the first in the list
|
|
struct Libp2pLinkedList* new_head = libp2p_utils_linked_list_new();
|
|
new_head->item = new_ma;
|
|
new_head->next = peer->addr_head;
|
|
peer->addr_head = new_head;
|
|
// now add the peer to the peerstore
|
|
libp2p_logger_debug("dht_protocol", "About to add peer %s to peerstore\n", peer_ma->string);
|
|
if (!libp2p_peerstore_add_peer(peerstore, peer))
|
|
goto exit;
|
|
libp2p_logger_debug("dht_protocol", "About to add key to providerstore\n");
|
|
if (!libp2p_providerstore_add(providerstore, message->key, message->key_size, peer->id, peer->id_size))
|
|
goto exit;
|
|
}
|
|
|
|
if (!libp2p_routing_dht_protobuf_message(message, result_buffer, result_buffer_size)) {
|
|
goto exit;
|
|
}
|
|
|
|
retVal = 1;
|
|
exit:
|
|
if (retVal != 1) {
|
|
if (*result_buffer != NULL) {
|
|
free(*result_buffer);
|
|
*result_buffer_size = 0;
|
|
*result_buffer = NULL;
|
|
}
|
|
libp2p_logger_error("dht_protocol", "add_provider returning false\n");
|
|
}
|
|
/*
|
|
if (peer != NULL)
|
|
libp2p_peer_free(peer);
|
|
*/
|
|
return retVal;
|
|
}
|
|
|
|
/**
|
|
* Retrieve something from the dht datastore
|
|
* @param session the session context
|
|
* @param message the message
|
|
* @param peerstore the peerstore
|
|
* @param providerstore the providerstore
|
|
* @param result_buffer the results
|
|
* @param result_buffer_size the size of the results
|
|
* @returns true(1) on success, otherwise false(0)
|
|
*/
|
|
int libp2p_routing_dht_handle_get_value(struct SessionContext* session, struct Libp2pMessage* message,
|
|
struct Peerstore* peerstore, struct ProviderStore* providerstore, unsigned char** result_buffer, size_t *result_buffer_size) {
|
|
|
|
struct Datastore* datastore = session->datastore;
|
|
struct Filestore* filestore = session->filestore;
|
|
size_t data_size = 0;
|
|
unsigned char* data = NULL;
|
|
|
|
// We need to get the data from the disk
|
|
if(!filestore->node_get(message->key, message->key_size, (void**)&data, &data_size, filestore)) {
|
|
libp2p_logger_debug("dht_protocol", "handle_get_value: Unable to get key from filestore\n");
|
|
}
|
|
|
|
libp2p_logger_debug("dht_protocol", "handle_get_value: value retrieved from the datastore\n");
|
|
|
|
struct Libp2pRecord *record = libp2p_record_new();
|
|
record->key_size = message->key_size;
|
|
record->key = malloc(record->key_size);
|
|
memcpy(record->key, message->key, record->key_size);
|
|
record->value_size = data_size;
|
|
record->value = malloc(record->value_size);
|
|
memcpy(record->value, data, record->value_size);
|
|
message->record = record;
|
|
free(data);
|
|
|
|
if (!libp2p_routing_dht_protobuf_message(message, result_buffer, result_buffer_size)) {
|
|
libp2p_record_free(record);
|
|
message->record = NULL;
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/**
|
|
* Put something in the dht datastore
|
|
* @param session the session context
|
|
* @param message the message
|
|
* @param peerstore the peerstore
|
|
* @param providerstore the providerstore
|
|
* @param result_buffer the results
|
|
* @param result_buffer_size the size of the results
|
|
* @returns true(1) on success, otherwise false(0)
|
|
*/
|
|
int libp2p_routing_dht_handle_put_value(struct SessionContext* session, struct Libp2pMessage* message,
|
|
struct Peerstore* peerstore, struct ProviderStore* providerstore, unsigned char** result_buffer, size_t *result_buffer_size) {
|
|
//TODO: implement this
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* Find a node
|
|
* @param session the session context
|
|
* @param message the message
|
|
* @param peerstore the peerstore
|
|
* @param providerstore the providerstore
|
|
* @param result_buffer the results
|
|
* @param result_buffer_size the size of the results
|
|
* @returns true(1) on success, otherwise false(0)
|
|
*/
|
|
int libp2p_routing_dht_handle_find_node(struct SessionContext* session, struct Libp2pMessage* message,
|
|
struct Peerstore* peerstore, struct ProviderStore* providerstore, unsigned char** result_buffer, size_t *result_buffer_size) {
|
|
// look through peer store
|
|
struct Libp2pPeer* peer = libp2p_peerstore_get_peer(peerstore, message->key, message->key_size);
|
|
if (peer != NULL) {
|
|
message->provider_peer_head = libp2p_utils_linked_list_new();
|
|
message->provider_peer_head->item = libp2p_peer_copy(peer);
|
|
if (!libp2p_routing_dht_protobuf_message(message, result_buffer, result_buffer_size)) {
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/***
|
|
* Handle the incoming message. Handshake should have already
|
|
* been done. We should expect that the next read contains
|
|
* a protobuf'd kademlia message.
|
|
* @param session the context
|
|
* @param peerstore a list of peers
|
|
* @returns true(1) on success, otherwise false(0)
|
|
*/
|
|
int libp2p_routing_dht_handle_message(struct SessionContext* session, struct Peerstore* peerstore, struct ProviderStore* providerstore) {
|
|
unsigned char* buffer = NULL, *result_buffer = NULL;
|
|
size_t buffer_size = 0, result_buffer_size = 0;
|
|
int retVal = 0;
|
|
struct Libp2pMessage* message = NULL;
|
|
|
|
// read from stream
|
|
if (!session->default_stream->read(session, &buffer, &buffer_size, 5))
|
|
goto exit;
|
|
// unprotobuf
|
|
if (!libp2p_message_protobuf_decode(buffer, buffer_size, &message))
|
|
goto exit;
|
|
|
|
// handle message
|
|
switch(message->message_type) {
|
|
case(MESSAGE_TYPE_PUT_VALUE): // store a value in local storage
|
|
libp2p_routing_dht_handle_put_value(session, message, peerstore, providerstore, &result_buffer, &result_buffer_size);
|
|
break;
|
|
case(MESSAGE_TYPE_GET_VALUE): // get a value from local storage
|
|
libp2p_routing_dht_handle_get_value(session, message, peerstore, providerstore, &result_buffer, &result_buffer_size);
|
|
break;
|
|
case(MESSAGE_TYPE_ADD_PROVIDER): // client wants us to know he can provide something
|
|
libp2p_routing_dht_handle_add_provider(session, message, peerstore, providerstore, &result_buffer, &result_buffer_size);
|
|
break;
|
|
case(MESSAGE_TYPE_GET_PROVIDERS): // see if we can help, and send closer peers
|
|
libp2p_routing_dht_handle_get_providers(session, message, peerstore, providerstore, &result_buffer, &result_buffer_size);
|
|
break;
|
|
case(MESSAGE_TYPE_FIND_NODE): // find peers
|
|
libp2p_routing_dht_handle_find_node(session, message, peerstore, providerstore, &result_buffer, &result_buffer_size);
|
|
break;
|
|
case(MESSAGE_TYPE_PING):
|
|
libp2p_routing_dht_handle_ping(message, &result_buffer, &result_buffer_size);
|
|
break;
|
|
}
|
|
// if we have something to send, send it.
|
|
if (result_buffer != NULL) {
|
|
libp2p_logger_debug("dht_protocol", "Sending message back to caller. Message type: %d\n", message->message_type);
|
|
if (!session->default_stream->write(session, result_buffer, result_buffer_size))
|
|
goto exit;
|
|
} else {
|
|
libp2p_logger_debug("dht_protocol", "DhtHandleMessage: Nothing to send back. Kademlia call has been handled. Message type: %d\n", message->message_type);
|
|
}
|
|
retVal = 1;
|
|
exit:
|
|
if (buffer != NULL)
|
|
free(buffer);
|
|
if (result_buffer != NULL)
|
|
free(result_buffer);
|
|
if (message != NULL)
|
|
libp2p_message_free(message);
|
|
return retVal;
|
|
}
|