test-cli/update-channel-htlc: new util.

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

Makefile

@@ -8,7 +8,7 @@ FEATURES := -DHAS_CSV=1 -DALPHA_TXSTYLE=1 -DUSE_SCHNORR=1 -DHAS_CLTV=1
 # Bitcoin uses DER for signatures
 #FEATURES := -DSCRIPTS_USE_DER
 
-PROGRAMS := test-cli/open-channel test-cli/create-anchor-tx test-cli/open-commit-sig test-cli/check-commit-sig test-cli/get-anchor-depth test-cli/create-steal-tx test-cli/create-commit-spend-tx test-cli/close-channel test-cli/create-close-tx test-cli/update-channel test-cli/update-channel-accept test-cli/update-channel-signature test-cli/update-channel-complete test-cli/create-commit-tx test-cli/txid-of test-cli/open-anchor
+PROGRAMS := test-cli/open-channel test-cli/create-anchor-tx test-cli/open-commit-sig test-cli/check-commit-sig test-cli/get-anchor-depth test-cli/create-steal-tx test-cli/create-commit-spend-tx test-cli/close-channel test-cli/create-close-tx test-cli/update-channel test-cli/update-channel-accept test-cli/update-channel-signature test-cli/update-channel-complete test-cli/create-commit-tx test-cli/txid-of test-cli/open-anchor test-cli/update-channel-htlc
 
 BITCOIN_OBJS := bitcoin/address.o bitcoin/base58.o bitcoin/pubkey.o bitcoin/script.o bitcoin/shadouble.o bitcoin/signature.o bitcoin/tx.o
 

pkt.c

@@ -140,6 +140,25 @@ struct pkt *update_pkt(const tal_t *ctx,
 	return to_pkt(ctx, PKT__PKT_UPDATE, &u);
 }
 
+struct pkt *update_htlc_add_pkt(const tal_t *ctx,
+				const struct sha256 *revocation_hash,
+				u64 value,
+				const struct sha256 *htlc_rhash,
+				u32 abs_locktime_seconds)
+{
+	UpdateAddHtlc u = UPDATE_ADD_HTLC__INIT;
+	Locktime l = LOCKTIME__INIT;
+
+	u.revocation_hash = sha256_to_proto(ctx, revocation_hash);
+	u.amount = value;
+	u.r_hash = sha256_to_proto(ctx, htlc_rhash);
+	l.locktime_case = LOCKTIME__LOCKTIME_SECONDS;
+	l.seconds = abs_locktime_seconds;
+	u.expiry = &l;
+
+	return to_pkt(ctx, PKT__PKT_UPDATE_ADD_HTLC, &u);
+}
+
 struct pkt *update_accept_pkt(const tal_t *ctx,
 			      struct signature *sig,
 			      const struct sha256 *revocation_hash)

pkt.h

@@ -90,6 +90,20 @@ struct pkt *update_pkt(const tal_t *ctx,
 		       const struct sha256 *revocation_hash,
 		       s64 delta);
 
+/**
+ * update_htlc_add_pkt - create an update message adding a HTLC
+ * @ctx: tal context to allocate off.
+ * @revocation_hash: the revocation hash for the next commitment tx.
+ * @val: the change in satoshis (from me).
+ * @htlc_rhash: the hash of the htlc secret.
+ * @abs_locktime_seconds: the HTLC timeout.
+ */
+struct pkt *update_htlc_add_pkt(const tal_t *ctx,
+				const struct sha256 *revocation_hash,
+				u64 value,
+				const struct sha256 *htlc_rhash,
+				u32 abs_locktime_seconds);
+
 /**
  * update_accept_pkt - create an update_accept message
  * @ctx: tal context to allocate off.

test-cli/.gitignore

@@ -17,3 +17,4 @@ create-commit-tx
 open-anchor
 txid-of
 create-anchor-tx
+update-channel-htlc

test-cli/update-channel-htlc.c

@@ -0,0 +1,74 @@
+#include <ccan/crypto/shachain/shachain.h>
+#include <ccan/short_types/short_types.h>
+#include <ccan/tal/tal.h>
+#include <ccan/opt/opt.h>
+#include <ccan/str/hex/hex.h>
+#include <ccan/err/err.h>
+#include <ccan/read_write_all/read_write_all.h>
+#include "lightning.pb-c.h"
+#include "bitcoin/base58.h"
+#include "pkt.h"
+#include "bitcoin/script.h"
+#include "permute_tx.h"
+#include "bitcoin/signature.h"
+#include "commit_tx.h"
+#include "bitcoin/pubkey.h"
+#include "find_p2sh_out.h"
+#include <unistd.h>
+
+int main(int argc, char *argv[])
+{
+	const tal_t *ctx = tal_arr(NULL, char, 0);
+	struct sha256 seed, revocation_hash, rval, rhash;
+	struct pkt *pkt;
+	uint64_t htlc_val;
+	u32 locktime_seconds;
+	unsigned update_num;
+	char *endp;
+
+	err_set_progname(argv[0]);
+
+	opt_register_noarg("--help|-h", opt_usage_and_exit,
+			   "<seed> <update-number> <satoshi> <r-value> <abs-locktime-seconds>\n"
+			   "Create a new HTLC update message",
+			   "Print this message.");
+
+ 	opt_parse(&argc, argv, opt_log_stderr_exit);
+
+	if (argc != 6)
+		opt_usage_exit_fail("Expected 5 arguments");
+
+	if (!hex_decode(argv[1], strlen(argv[1]), &seed, sizeof(seed)))
+		errx(1, "Invalid seed '%s' - need 256 hex bits", argv[1]);
+	update_num = atoi(argv[2]);
+	if (!update_num)
+		errx(1, "Update number %s invalid", argv[2]);
+
+	htlc_val = strtol(argv[3], &endp, 10);
+	if (*endp || !htlc_val)
+		errx(1, "Expected number for %s", argv[3]);
+
+	if (!hex_decode(argv[4], strlen(argv[4]), &rval, sizeof(rval)))
+		errx(1, "Invalid rvalue '%s' - need 256 hex bits", argv[4]);
+
+	locktime_seconds = strtol(argv[5], &endp, 10);
+	if (*endp || !locktime_seconds)
+		errx(1, "Expected locktime for %s", argv[5]);
+
+	/* Get next revocation hash. */
+	shachain_from_seed(&seed, update_num, &revocation_hash);
+	sha256(&revocation_hash,
+	       revocation_hash.u.u8, sizeof(revocation_hash.u.u8));
+
+	/* Get htlc rvalue hash. */
+	sha256(&rhash, &rval, sizeof(rval));
+	
+	pkt = update_htlc_add_pkt(ctx, &revocation_hash, htlc_val,
+				  &rhash, locktime_seconds);
+	if (!write_all(STDOUT_FILENO, pkt, pkt_totlen(pkt)))
+		err(1, "Writing out packet");
+
+	tal_free(ctx);
+	return 0;
+}
+