daemon: code to open channel and watch anchor.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

daemon/packets.c

@@ -1,4 +1,5 @@
 #include "bitcoin/script.h"
+#include "bitcoin/tx.h"
 #include "find_p2sh_out.h"
 #include "lightningd.h"
 #include "log.h"
@@ -9,9 +10,29 @@
 #include "state.h"
 #include <ccan/crypto/sha256/sha256.h>
 #include <ccan/mem/mem.h>
+#include <ccan/str/hex/hex.h>
 
 #define FIXME_STUB(peer) do { log_broken((peer)->dstate->base_log, "%s:%u: Implement %s!", __FILE__, __LINE__, __func__); abort(); } while(0)
 
+static char *hex_of(const tal_t *ctx, const void *p, size_t n)
+{
+	char *hex = tal_arr(ctx, char, hex_str_size(n));
+	hex_encode(p, n, hex, hex_str_size(n));
+	return hex;
+}
+
+static void dump_tx(const char *str, const struct bitcoin_tx *tx)
+{
+	u8 *linear = linearize_tx(NULL, tx);
+	printf("%s:%s\n", str, hex_of(linear, linear, tal_count(linear)));
+	tal_free(linear);
+}
+
+static void dump_key(const char *str, const struct pubkey *key)
+{
+	printf("%s:%s\n", str, hex_of(NULL, key->der, pubkey_derlen(key)));
+}
+
 /* Wrap (and own!) member inside Pkt */
 static Pkt *make_pkt(const tal_t *ctx, Pkt__PktCase type, const void *msg)
 {
@@ -86,12 +107,26 @@ Pkt *pkt_anchor(const tal_t *ctx, const struct peer *peer)
 
 Pkt *pkt_open_commit_sig(const tal_t *ctx, const struct peer *peer)
 {
-	FIXME_STUB(peer);
+	struct signature sig;
+	OpenCommitSig *s = tal(ctx, OpenCommitSig);
+
+	open_commit_sig__init(s);
+
+	dump_tx("Creating sig for:", peer->them.commit);
+	dump_key("Using key:", &peer->us.commitkey);
+
+	peer_sign_theircommit(peer, &sig);
+	s->sig = signature_to_proto(s, &sig);
+
+	return make_pkt(ctx, PKT__PKT_OPEN_COMMIT_SIG, s);
 }
 
 Pkt *pkt_open_complete(const tal_t *ctx, const struct peer *peer)
 {
-	FIXME_STUB(peer);
+	OpenComplete *o = tal(ctx, OpenComplete);
+
+	open_complete__init(o);
+	return make_pkt(ctx, PKT__PKT_OPEN_COMPLETE, o);
 }
 
 Pkt *pkt_htlc_update(const tal_t *ctx, const struct peer *peer,
@@ -252,7 +287,25 @@ Pkt *accept_pkt_anchor(const tal_t *ctx,
 Pkt *accept_pkt_open_commit_sig(const tal_t *ctx,
 				struct peer *peer, const Pkt *pkt)
 {
-	FIXME_STUB(peer);
+	const OpenCommitSig *s = pkt->open_commit_sig;
+
+	peer->cur_commit_theirsig.stype = SIGHASH_ALL;
+	if (!proto_to_signature(s->sig, &peer->cur_commit_theirsig.sig))
+		return pkt_err(ctx, "Malformed signature");
+
+	dump_tx("Checking sig for:", peer->us.commit);
+	dump_key("Using key:", &peer->them.commitkey);
+
+	/* Their sig should sign our commit tx. */
+	if (!check_tx_sig(peer->dstate->secpctx,
+			  peer->us.commit, 0,
+			  peer->anchor.redeemscript,
+			  tal_count(peer->anchor.redeemscript),
+			  &peer->them.commitkey,
+			  &peer->cur_commit_theirsig))
+		return pkt_err(ctx, "Bad signature");
+
+	return NULL;
 }
 	
 Pkt *accept_pkt_htlc_update(const tal_t *ctx,

daemon/peer.c

@@ -17,6 +17,7 @@
 #include <ccan/io/io.h>
 #include <ccan/list/list.h>
 #include <ccan/noerr/noerr.h>
+#include <ccan/structeq/structeq.h>
 #include <ccan/tal/str/str.h>
 #include <ccan/tal/tal.h>
 #include <errno.h>
@@ -439,7 +440,6 @@ const struct json_command connect_command = {
 };
 
 struct anchor_watch {
-	struct peer *peer;
 	enum state_input depthok;
 	enum state_input timeout;
 	enum state_input unspent;
@@ -447,6 +447,71 @@ struct anchor_watch {
 	enum state_input otherspent;
 };
 
+static void anchor_depthchange(struct peer *peer, int depth,
+			       struct anchor_watch *w)
+{
+	/* Still waiting for it to reach depth? */
+	if (w->depthok != INPUT_NONE) {
+		/* Beware sign! */
+		if (depth >= (int)peer->us.mindepth) {
+			enum state_input in = w->depthok;
+			w->depthok = INPUT_NONE;
+			update_state(peer, in, NULL);
+		}
+	} else {
+		if (depth < 0 && w->unspent != INPUT_NONE) {
+			enum state_input in = w->unspent;
+			w->unspent = INPUT_NONE;
+			update_state(peer, in, NULL);
+		}
+	}
+}
+
+/* We don't compare scriptSigs: we don't know them anyway! */
+static bool txmatch(const struct bitcoin_tx *txa, const struct bitcoin_tx *txb)
+{
+	size_t i;
+
+	if (txa->version != txb->version
+	    || txa->input_count != txb->input_count
+	    || txa->output_count != txb->output_count
+	    || txa->lock_time != txb->lock_time)
+		return false;
+
+	for (i = 0; i < txa->input_count; i++) {
+		if (!structeq(&txa->input[i].txid, &txb->input[i].txid)
+		    || txa->input[i].index != txb->input[i].index
+		    || txa->input[i].sequence_number != txb->input[i].sequence_number)
+			return false;
+	}
+
+	for (i = 0; i < txa->output_count; i++) {
+		if (txa->output[i].amount != txb->output[i].amount
+		    || txa->output[i].script_length != txb->output[i].script_length
+		    || memcmp(txa->output[i].script, txb->output[i].script,
+			      txa->output[i].script_length != 0))
+			return false;
+	}
+
+	return true;
+}
+
+/* We assume the tx is valid!  Don't do a blockchain.info and feed this
+ * invalid transactions! */
+static void anchor_spent(struct peer *peer,
+			 const struct bitcoin_tx *tx,
+			 struct anchor_watch *w)
+{
+	union input idata;
+
+	/* FIXME: change type in idata? */
+	idata.btc = (struct bitcoin_event *)tx;
+	if (txmatch(tx, peer->them.commit))
+		update_state(peer, w->theyspent, &idata);
+	else
+		update_state(peer, w->otherspent, &idata);
+}
+
 void peer_watch_anchor(struct peer *peer,
 		       enum state_input depthok,
 		       enum state_input timeout,
@@ -454,7 +519,20 @@ void peer_watch_anchor(struct peer *peer,
 		       enum state_input theyspent,
 		       enum state_input otherspent)
 {
-	FIXME_STUB(peer);
+	struct anchor_watch *w = tal(peer, struct anchor_watch);
+
+	w->depthok = depthok;
+	w->timeout = timeout;
+	w->unspent = unspent;
+	w->theyspent = theyspent;
+	w->otherspent = otherspent;
+
+	add_anchor_watch(peer, &peer->anchor.txid, peer->anchor.index,
+			 anchor_depthchange,
+			 anchor_spent,
+			 w);
+
+	/* FIXME: add timeout */
 }
 
 void peer_unwatch_anchor_depth(struct peer *peer,