@ -27,12 +27,15 @@
# include <ccan/tal/str/str.h>
# include <common/bech32.h>
# include <common/bech32_util.h>
# include <common/blinding.h>
# include <common/cryptomsg.h>
# include <common/daemon_conn.h>
# include <common/ecdh_hsmd.h>
# include <common/features.h>
# include <common/memleak.h>
# include <common/ping.h>
# include <common/pseudorand.h>
# include <common/sphinx.h>
# include <common/status.h>
# include <common/subdaemon.h>
# include <common/timeout.h>
@ -58,12 +61,16 @@
# include <netdb.h>
# include <netinet/in.h>
# include <secp256k1_ecdh.h>
# include <sodium/crypto_aead_chacha20poly1305.h>
# include <sodium/randombytes.h>
# include <sys/socket.h>
# include <sys/stat.h>
# include <sys/types.h>
# include <sys/un.h>
# include <unistd.h>
# if EXPERIMENTAL_FEATURES
# include <wire/bolt12_exp_wiregen.h>
# endif
# include <wire/wire_io.h>
# include <wire/wire_sync.h>
@ -428,6 +435,263 @@ static bool handle_local_channel_announcement(struct daemon *daemon,
return true ;
}
# if EXPERIMENTAL_FEATURES
/* Peer sends onion msg. */
static u8 * handle_onion_message ( struct peer * peer , const u8 * msg )
{
enum onion_wire badreason ;
struct onionpacket * op ;
struct secret ss , * blinding_ss ;
struct pubkey * blinding_in ;
struct route_step * rs ;
u8 onion [ TOTAL_PACKET_SIZE ( ROUTING_INFO_SIZE ) ] ;
const u8 * cursor ;
size_t max , maxlen ;
struct tlv_onionmsg_payload * om ;
struct tlv_onion_message_tlvs * tlvs = tlv_onion_message_tlvs_new ( msg ) ;
/* FIXME: ratelimit! */
if ( ! fromwire_onion_message ( msg , onion , tlvs ) )
return towire_errorfmt ( peer , NULL , " Bad onion_message " ) ;
/* We unwrap the onion now. */
op = parse_onionpacket ( tmpctx , onion , TOTAL_PACKET_SIZE ( ROUTING_INFO_SIZE ) , & badreason ) ;
if ( ! op ) {
status_debug ( " peer %s: onion msg: can't parse onionpacket: %s " ,
type_to_string ( tmpctx , struct node_id , & peer - > id ) ,
onion_wire_name ( badreason ) ) ;
return NULL ;
}
if ( tlvs - > blinding ) {
struct secret hmac ;
/* E(i) */
blinding_in = tal_dup ( msg , struct pubkey , tlvs - > blinding ) ;
status_debug ( " peer %s: blinding in = %s " ,
type_to_string ( tmpctx , struct node_id , & peer - > id ) ,
type_to_string ( tmpctx , struct pubkey , blinding_in ) ) ;
blinding_ss = tal ( msg , struct secret ) ;
ecdh ( blinding_in , blinding_ss ) ;
/* b(i) = HMAC256("blinded_node_id", ss(i)) * k(i) */
subkey_from_hmac ( " blinded_node_id " , blinding_ss , & hmac ) ;
/* We instead tweak the *ephemeral* key from the onion and use
* our normal privkey : since hsmd knows only how to ECDH with
* our real key */
if ( secp256k1_ec_pubkey_tweak_mul ( secp256k1_ctx ,
& op - > ephemeralkey . pubkey ,
hmac . data ) ! = 1 ) {
status_debug ( " peer %s: onion msg: can't tweak pubkey " ,
type_to_string ( tmpctx , struct node_id , & peer - > id ) ) ;
return NULL ;
}
} else {
blinding_ss = NULL ;
blinding_in = NULL ;
}
ecdh ( & op - > ephemeralkey , & ss ) ;
/* We make sure we can parse onion packet, so we know if shared secret
* is actually valid ( this checks hmac ) . */
rs = process_onionpacket ( tmpctx , op , & ss , NULL , 0 , false ) ;
if ( ! rs ) {
status_debug ( " peer %s: onion msg: can't process onionpacket ss=%s " ,
type_to_string ( tmpctx , struct node_id , & peer - > id ) ,
type_to_string ( tmpctx , struct secret , & ss ) ) ;
return NULL ;
}
/* The raw payload is prepended with length in the TLV world. */
cursor = rs - > raw_payload ;
max = tal_bytelen ( rs - > raw_payload ) ;
maxlen = fromwire_bigsize ( & cursor , & max ) ;
if ( ! cursor ) {
status_debug ( " peer %s: onion msg: Invalid hop payload %s " ,
type_to_string ( tmpctx , struct node_id , & peer - > id ) ,
tal_hex ( tmpctx , rs - > raw_payload ) ) ;
return NULL ;
}
if ( maxlen > max ) {
status_debug ( " peer %s: onion msg: overlong hop payload %s " ,
type_to_string ( tmpctx , struct node_id , & peer - > id ) ,
tal_hex ( tmpctx , rs - > raw_payload ) ) ;
return NULL ;
}
om = tlv_onionmsg_payload_new ( msg ) ;
if ( ! fromwire_onionmsg_payload ( & cursor , & maxlen , om ) ) {
status_debug ( " peer %s: onion msg: invalid onionmsg_payload %s " ,
type_to_string ( tmpctx , struct node_id , & peer - > id ) ,
tal_hex ( tmpctx , rs - > raw_payload ) ) ;
return NULL ;
}
/* If we weren't given a blinding factor, tlv can provide one. */
if ( om - > blinding & & ! blinding_ss ) {
/* E(i) */
blinding_in = tal_dup ( msg , struct pubkey , om - > blinding ) ;
blinding_ss = tal ( msg , struct secret ) ;
ecdh ( blinding_in , blinding_ss ) ;
}
if ( om - > enctlv ) {
const unsigned char npub [ crypto_aead_chacha20poly1305_ietf_NPUBBYTES ] = { 0x00 , 0x00 , 0x00 , 0x00 , 0x00 , 0x00 , 0x00 , 0x00 , 0x00 , 0x00 , 0x00 , 0x00 } ;
u8 * dec ;
struct secret rho ;
int ret ;
if ( ! blinding_ss ) {
status_debug ( " peer %s: enctlv but no blinding? " ,
type_to_string ( tmpctx , struct node_id , & peer - > id ) ) ;
return NULL ;
}
/* We need this to decrypt enctlv */
subkey_from_hmac ( " rho " , blinding_ss , & rho ) ;
/* Overrides next_scid / next_node */
if ( tal_bytelen ( om - > enctlv )
< crypto_aead_chacha20poly1305_ietf_ABYTES ) {
status_debug ( " peer %s: enctlv too short for mac " ,
type_to_string ( tmpctx , struct node_id , & peer - > id ) ) ;
return NULL ;
}
dec = tal_arr ( msg , u8 ,
tal_bytelen ( om - > enctlv )
- crypto_aead_chacha20poly1305_ietf_ABYTES ) ;
ret = crypto_aead_chacha20poly1305_ietf_decrypt ( dec , NULL ,
NULL ,
om - > enctlv ,
tal_bytelen ( om - > enctlv ) ,
NULL , 0 ,
npub ,
rho . data ) ;
if ( ret ! = 0 ) {
status_debug ( " peer %s: Failed to decrypt enctlv field " ,
type_to_string ( tmpctx , struct node_id , & peer - > id ) ) ;
return NULL ;
}
status_debug ( " peer %s: enctlv -> %s " ,
type_to_string ( tmpctx , struct node_id , & peer - > id ) ,
tal_hex ( tmpctx , dec ) ) ;
/* Replace onionmsg with one from enctlv */
cursor = dec ;
maxlen = tal_bytelen ( dec ) ;
om = tlv_onionmsg_payload_new ( msg ) ;
if ( ! fromwire_onionmsg_payload ( & cursor , & maxlen , om ) ) {
status_debug ( " peer %s: onion msg: invalid enctlv onionmsg_payload %s " ,
type_to_string ( tmpctx , struct node_id , & peer - > id ) ,
tal_hex ( tmpctx , dec ) ) ;
return NULL ;
}
} else if ( blinding_ss & & rs - > nextcase ! = ONION_END ) {
status_debug ( " peer %s: Onion had %s, but not enctlv? " ,
type_to_string ( tmpctx , struct node_id , & peer - > id ) ,
tlvs - > blinding ? " blinding " : " om blinding " ) ;
return NULL ;
}
if ( rs - > nextcase = = ONION_END ) {
struct pubkey * blinding ;
const struct onionmsg_path * * path ;
u8 * omsg ;
if ( om - > reply_path ) {
blinding = & om - > reply_path - > blinding ;
path = cast_const2 ( const struct onionmsg_path * * ,
om - > reply_path - > path ) ;
} else {
blinding = NULL ;
path = NULL ;
}
/* We re-marshall here by policy, before handing to lightningd */
omsg = tal_arr ( tmpctx , u8 , 0 ) ;
towire_tlvstream_raw ( & omsg , om - > fields ) ;
daemon_conn_send ( peer - > daemon - > master ,
take ( towire_gossipd_got_onionmsg_to_us ( NULL ,
blinding_in ,
blinding ,
path ,
omsg ) ) ) ;
} else {
struct pubkey * next_blinding ;
struct node_id * next_node ;
/* This *MUST* have instructions on where to go next. */
if ( ! om - > next_short_channel_id & & ! om - > next_node_id ) {
status_debug ( " peer %s: onion msg: no next field in %s " ,
type_to_string ( tmpctx , struct node_id , & peer - > id ) ,
tal_hex ( tmpctx , rs - > raw_payload ) ) ;
return NULL ;
}
if ( blinding_ss ) {
/* E(i-1) = H(E(i) || ss(i)) * E(i) */
struct sha256 h ;
blinding_hash_e_and_ss ( blinding_in , blinding_ss , & h ) ;
next_blinding = tal ( msg , struct pubkey ) ;
blinding_next_pubkey ( blinding_in , & h , next_blinding ) ;
} else
next_blinding = NULL ;
if ( om - > next_node_id ) {
next_node = tal ( tmpctx , struct node_id ) ;
node_id_from_pubkey ( next_node , om - > next_node_id ) ;
} else
next_node = NULL ;
daemon_conn_send ( peer - > daemon - > master ,
take ( towire_gossipd_got_onionmsg_forward ( NULL ,
om - > next_short_channel_id ,
next_node ,
next_blinding ,
serialize_onionpacket ( tmpctx , rs - > next ) ) ) ) ;
}
return NULL ;
}
/* We send onion msg. */
static struct io_plan * onionmsg_req ( struct io_conn * conn , struct daemon * daemon ,
const u8 * msg )
{
struct node_id id ;
u8 onion_routing_packet [ TOTAL_PACKET_SIZE ( ROUTING_INFO_SIZE ) ] ;
struct pubkey * blinding ;
struct peer * peer ;
if ( ! fromwire_gossipd_send_onionmsg ( msg , msg , & id , onion_routing_packet ,
& blinding ) )
master_badmsg ( WIRE_GOSSIPD_SEND_ONIONMSG , msg ) ;
/* Even if lightningd were to check for valid ids, there's a race
* where it might vanish before we read this command ; cleaner to
* handle it here with ' sent ' = false . */
peer = find_peer ( daemon , & id ) ;
if ( peer ) {
struct tlv_onion_message_tlvs * tlvs ;
tlvs = tlv_onion_message_tlvs_new ( msg ) ;
if ( blinding )
tlvs - > blinding = tal_dup ( tlvs , struct pubkey , blinding ) ;
queue_peer_msg ( peer ,
take ( towire_onion_message ( NULL ,
onion_routing_packet ,
tlvs ) ) ) ;
}
return daemon_conn_read_next ( conn , daemon - > master ) ;
}
# endif /* EXPERIMENTAL_FEATURES */
/*~ This is where the per-peer daemons send us messages. It's either forwarded
* gossip , or a request for information . We deliberately use non - overlapping
* message types so we can distinguish them . */
@ -467,6 +731,11 @@ static struct io_plan *peer_msg_in(struct io_conn *conn,
case WIRE_PONG :
err = handle_pong ( peer , msg ) ;
goto handled_relay ;
# if EXPERIMENTAL_FEATURES
case WIRE_ONION_MESSAGE :
err = handle_onion_message ( peer , msg ) ;
goto handled_relay ;
# endif
/* These are non-gossip messages (!is_msg_for_gossipd()) */
case WIRE_INIT :
@ -489,7 +758,6 @@ static struct io_plan *peer_msg_in(struct io_conn *conn,
case WIRE_ANNOUNCEMENT_SIGNATURES :
case WIRE_GOSSIP_TIMESTAMP_FILTER :
# if EXPERIMENTAL_FEATURES
case WIRE_ONION_MESSAGE :
case WIRE_TX_ADD_INPUT :
case WIRE_TX_REMOVE_INPUT :
case WIRE_TX_ADD_OUTPUT :
@ -1662,6 +1930,10 @@ static struct io_plan *recv_req(struct io_conn *conn,
break ;
# endif /* !DEVELOPER */
case WIRE_GOSSIPD_SEND_ONIONMSG :
# if EXPERIMENTAL_FEATURES
return onionmsg_req ( conn , daemon , msg ) ;
# endif
/* We send these, we don't receive them */
case WIRE_GOSSIPD_GETNODES_REPLY :
case WIRE_GOSSIPD_GETROUTE_REPLY :
@ -1672,6 +1944,8 @@ static struct io_plan *recv_req(struct io_conn *conn,
case WIRE_GOSSIPD_GET_TXOUT :
case WIRE_GOSSIPD_DEV_MEMLEAK_REPLY :
case WIRE_GOSSIPD_DEV_COMPACT_STORE_REPLY :
case WIRE_GOSSIPD_GOT_ONIONMSG_TO_US :
case WIRE_GOSSIPD_GOT_ONIONMSG_FORWARD :
break ;
}
@ -1703,6 +1977,9 @@ int main(int argc, char *argv[])
daemon - > node_announce_timer = NULL ;
daemon - > current_blockheight = 0 ; /* i.e. unknown */
/* Tell the ecdh() function how to talk to hsmd */
ecdh_hsmd_setup ( HSM_FD , status_failed ) ;
/* Note the use of time_mono() here. That's a monotonic clock, which
* is really useful : it can only be used to measure relative events
* ( there ' s no correspondence to time - since - Ken - grew - a - beard or
Rusty Russell
4 years ago