core-lightning/lightningd/dev_ping.c
Rusty Russell b536e97df2 dev_ping: don't crash with silly values.
It's a dev command, but still.

Fixes: #985
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2018-02-22 01:10:09 +00:00

137 lines
3.5 KiB
C

#include <channeld/gen_channel_wire.h>
#include <common/sphinx.h>
#include <common/utils.h>
#include <gossipd/gen_gossip_wire.h>
#include <lightningd/htlc_end.h>
#include <lightningd/jsonrpc.h>
#include <lightningd/lightningd.h>
#include <lightningd/log.h>
#include <lightningd/peer_control.h>
#include <lightningd/subd.h>
static void ping_reply(struct subd *subd, const u8 *msg, const int *fds UNUSED,
struct command *cmd)
{
u16 totlen;
bool ok, sent = true;
log_debug(subd->ld->log, "Got ping reply!");
if (streq(subd->name, "lightning_channeld"))
ok = fromwire_channel_ping_reply(msg, &totlen);
else
ok = fromwire_gossip_ping_reply(msg, &sent, &totlen);
if (!ok)
command_fail(cmd, "Bad reply message");
else if (!sent)
command_fail(cmd, "Unknown peer");
else {
struct json_result *response = new_json_result(cmd);
json_object_start(response, NULL);
json_add_num(response, "totlen", totlen);
json_object_end(response);
command_success(cmd, response);
}
}
static void json_dev_ping(struct command *cmd,
const char *buffer, const jsmntok_t *params)
{
struct peer *peer;
u8 *msg;
jsmntok_t *idtok, *lentok, *pongbytestok;
unsigned int len, pongbytes;
struct pubkey id;
struct subd *owner;
if (!json_get_params(cmd, buffer, params,
"id", &idtok,
"len", &lentok,
"pongbytes", &pongbytestok,
NULL)) {
return;
}
/* FIXME: These checks are horrible, use a peer flag to say it's
* ready to forward! */
if (!json_tok_number(buffer, lentok, &len)) {
command_fail(cmd, "'%.*s' is not a valid number",
lentok->end - lentok->start,
buffer + lentok->start);
return;
}
/* BOLT #1:
*
* 1. `type`: a 2-byte big-endian field indicating the type of message
* 2. `payload`
*...
* The size of the message is required by the transport layer to fit
* into a 2-byte unsigned int; therefore, the maximum possible size is
* 65535 bytes.
*...
* 1. type: 18 (`ping`)
* 2. data:
* * [`2`:`num_pong_bytes`]
* * [`2`:`byteslen`]
* * [`byteslen`:`ignored`]
*/
if (len > 65535 - 2 - 2 - 2) {
command_fail(cmd, "%u would result in oversize ping", len);
return;
}
if (!json_tok_number(buffer, pongbytestok, &pongbytes)) {
command_fail(cmd, "'%.*s' is not a valid number",
pongbytestok->end - pongbytestok->start,
buffer + pongbytestok->start);
return;
}
/* Note that > 65531 is valid: it means "no pong reply" */
if (pongbytes > 65535) {
command_fail(cmd, "pongbytes %u > 65535", pongbytes);
return;
}
if (!json_tok_pubkey(buffer, idtok, &id)) {
command_fail(cmd, "'%.*s' is not a valid pubkey",
idtok->end - idtok->start,
buffer + idtok->start);
return;
}
/* First, see if it's in channeld. */
peer = peer_by_id(cmd->ld, &id);
if (peer) {
struct channel *channel = peer_active_channel(peer);
if (!channel
|| !channel->owner
|| !streq(channel->owner->name, "lightning_channeld")) {
command_fail(cmd, "Peer in %s",
channel && channel->owner
? channel->owner->name
: "unattached");
return;
}
msg = towire_channel_ping(cmd, pongbytes, len);
owner = channel->owner;
} else {
/* We assume it's in gossipd. */
msg = towire_gossip_ping(cmd, &id, pongbytes, len);
owner = cmd->ld->gossip;
}
subd_req(owner, owner, take(msg), -1, 0, ping_reply, cmd);
command_still_pending(cmd);
}
static const struct json_command dev_ping_command = {
"dev-ping",
json_dev_ping,
"Send {peerid} a ping of length {len} asking for {pongbytes}"
};
AUTODATA(json_command, &dev_ping_command);