UTXO selection cleanups and preps

bitcoin/Makefile

@@ -4,6 +4,7 @@ BITCOIN_SRC :=					\
 	bitcoin/base58.c			\
 	bitcoin/block.c				\
 	bitcoin/chainparams.c			\
+	bitcoin/feerate.c			\
 	bitcoin/locktime.c			\
 	bitcoin/preimage.c			\
 	bitcoin/privkey.c			\

bitcoin/feerate.c

@@ -0,0 +1,40 @@
+#include <bitcoin/feerate.h>
+#include <limits.h>
+#include <stdlib.h>
+
+u32 feerate_from_style(u32 feerate, enum feerate_style style)
+{
+	switch (style) {
+	case FEERATE_PER_KSIPA:
+		return feerate;
+	case FEERATE_PER_KBYTE:
+		/* Everyone uses satoshi per kbyte, but we use satoshi per ksipa
+		 * (don't round down to zero though)! */
+		return (feerate + 3) / 4;
+	}
+	abort();
+}
+
+u32 feerate_to_style(u32 feerate_perkw, enum feerate_style style)
+{
+	switch (style) {
+	case FEERATE_PER_KSIPA:
+		return feerate_perkw;
+	case FEERATE_PER_KBYTE:
+		if ((u64)feerate_perkw * 4 > UINT_MAX)
+			return UINT_MAX;
+		return feerate_perkw * 4;
+	}
+	abort();
+}
+
+const char *feerate_style_name(enum feerate_style style)
+{
+	switch (style) {
+	case FEERATE_PER_KBYTE:
+		return "perkb";
+	case FEERATE_PER_KSIPA:
+		return "perkw";
+	}
+	abort();
+}

bitcoin/feerate.h

@@ -3,6 +3,7 @@
 #include "config.h"
 #include <ccan/build_assert/build_assert.h>
 #include <ccan/short_types/short_types.h>
+#include <common/amount.h>
 
 /* bitcoind considers 250 satoshi per kw to be the minimum acceptable fee:
  * less than this won't even relay.
@@ -33,6 +34,11 @@
  */
 #define FEERATE_FLOOR 253
 
+enum feerate_style {
+	FEERATE_PER_KSIPA,
+	FEERATE_PER_KBYTE
+};
+
 static inline u32 feerate_floor(void)
 {
 	/* Assert that bitcoind will see this as above minRelayTxFee */
@@ -47,4 +53,9 @@ static inline u32 feerate_floor(void)
 
 	return FEERATE_FLOOR;
 }
+
+u32 feerate_from_style(u32 feerate, enum feerate_style style);
+u32 feerate_to_style(u32 feerate_perkw, enum feerate_style style);
+const char *feerate_style_name(enum feerate_style style);
+
 #endif /* LIGHTNING_BITCOIN_FEERATE_H */

bitcoin/test/run-bitcoin_block_from_hex.c

@@ -21,14 +21,17 @@ struct amount_sat amount_asset_to_sat(struct amount_asset *asset UNNEEDED)
 /* Generated stub for amount_sat_eq */
 bool amount_sat_eq(struct amount_sat a UNNEEDED, struct amount_sat b UNNEEDED)
 { fprintf(stderr, "amount_sat_eq called!\n"); abort(); }
-/* Generated stub for amount_sat_less */
-bool amount_sat_less(struct amount_sat a UNNEEDED, struct amount_sat b UNNEEDED)
-{ fprintf(stderr, "amount_sat_less called!\n"); abort(); }
+/* Generated stub for amount_sat_greater_eq */
+bool amount_sat_greater_eq(struct amount_sat a UNNEEDED, struct amount_sat b UNNEEDED)
+{ fprintf(stderr, "amount_sat_greater_eq called!\n"); abort(); }
 /* Generated stub for amount_sat_sub */
  bool amount_sat_sub(struct amount_sat *val UNNEEDED,
 				       struct amount_sat a UNNEEDED,
 				       struct amount_sat b UNNEEDED)
 { fprintf(stderr, "amount_sat_sub called!\n"); abort(); }
+/* Generated stub for amount_tx_fee */
+struct amount_sat amount_tx_fee(u32 fee_per_kw UNNEEDED, size_t weight UNNEEDED)
+{ fprintf(stderr, "amount_tx_fee called!\n"); abort(); }
 /* Generated stub for fromwire */
 const u8 *fromwire(const u8 **cursor UNNEEDED, size_t *max UNNEEDED, void *copy UNNEEDED, size_t n UNNEEDED)
 { fprintf(stderr, "fromwire called!\n"); abort(); }

bitcoin/test/run-tx-encode.c

@@ -22,14 +22,17 @@ struct amount_sat amount_asset_to_sat(struct amount_asset *asset UNNEEDED)
 /* Generated stub for amount_sat_eq */
 bool amount_sat_eq(struct amount_sat a UNNEEDED, struct amount_sat b UNNEEDED)
 { fprintf(stderr, "amount_sat_eq called!\n"); abort(); }
-/* Generated stub for amount_sat_less */
-bool amount_sat_less(struct amount_sat a UNNEEDED, struct amount_sat b UNNEEDED)
-{ fprintf(stderr, "amount_sat_less called!\n"); abort(); }
+/* Generated stub for amount_sat_greater_eq */
+bool amount_sat_greater_eq(struct amount_sat a UNNEEDED, struct amount_sat b UNNEEDED)
+{ fprintf(stderr, "amount_sat_greater_eq called!\n"); abort(); }
 /* Generated stub for amount_sat_sub */
  bool amount_sat_sub(struct amount_sat *val UNNEEDED,
 				       struct amount_sat a UNNEEDED,
 				       struct amount_sat b UNNEEDED)
 { fprintf(stderr, "amount_sat_sub called!\n"); abort(); }
+/* Generated stub for amount_tx_fee */
+struct amount_sat amount_tx_fee(u32 fee_per_kw UNNEEDED, size_t weight UNNEEDED)
+{ fprintf(stderr, "amount_tx_fee called!\n"); abort(); }
 /* Generated stub for fromwire */
 const u8 *fromwire(const u8 **cursor UNNEEDED, size_t *max UNNEEDED, void *copy UNNEEDED, size_t n UNNEEDED)
 { fprintf(stderr, "fromwire called!\n"); abort(); }

bitcoin/tx.c

@@ -803,3 +803,20 @@ size_t bitcoin_tx_simple_input_weight(bool p2sh)
 
 	return weight;
 }
+
+struct amount_sat change_amount(struct amount_sat excess, u32 feerate_perkw)
+{
+	size_t outweight;
+
+	/* Must be able to pay for its own additional weight */
+	outweight = bitcoin_tx_output_weight(BITCOIN_SCRIPTPUBKEY_P2WPKH_LEN);
+	if (!amount_sat_sub(&excess,
+			    excess, amount_tx_fee(feerate_perkw, outweight)))
+		return AMOUNT_SAT(0);
+
+	/* Must be non-dust */
+	if (!amount_sat_greater_eq(excess, chainparams->dust_limit))
+		return AMOUNT_SAT(0);
+
+	return excess;
+}

bitcoin/tx.h

@@ -241,4 +241,15 @@ size_t bitcoin_tx_input_sig_weight(void);
 /* We only do segwit inputs, and we assume witness is sig + key  */
 size_t bitcoin_tx_simple_input_weight(bool p2sh);
 
+/**
+ * change_amount - Is it worth making a P2WPKH change output at this feerate?
+ * @excess: input amount we have above the tx fee and other outputs.
+ * @feerate_perkw: feerate.
+ *
+ * If it's not worth (or possible) to make change, returns AMOUNT_SAT(0).
+ * Otherwise returns the amount of the change output to add (@excess minus
+ * the additional fee for the change output itself).
+ */
+struct amount_sat change_amount(struct amount_sat excess, u32 feerate_perkw);
+
 #endif /* LIGHTNING_BITCOIN_TX_H */

cli/test/run-large-input.c

@@ -47,14 +47,17 @@ struct amount_sat amount_asset_to_sat(struct amount_asset *asset UNNEEDED)
 /* Generated stub for amount_sat_eq */
 bool amount_sat_eq(struct amount_sat a UNNEEDED, struct amount_sat b UNNEEDED)
 { fprintf(stderr, "amount_sat_eq called!\n"); abort(); }
-/* Generated stub for amount_sat_less */
-bool amount_sat_less(struct amount_sat a UNNEEDED, struct amount_sat b UNNEEDED)
-{ fprintf(stderr, "amount_sat_less called!\n"); abort(); }
+/* Generated stub for amount_sat_greater_eq */
+bool amount_sat_greater_eq(struct amount_sat a UNNEEDED, struct amount_sat b UNNEEDED)
+{ fprintf(stderr, "amount_sat_greater_eq called!\n"); abort(); }
 /* Generated stub for amount_sat_sub */
  bool amount_sat_sub(struct amount_sat *val UNNEEDED,
 				       struct amount_sat a UNNEEDED,
 				       struct amount_sat b UNNEEDED)
 { fprintf(stderr, "amount_sat_sub called!\n"); abort(); }
+/* Generated stub for amount_tx_fee */
+struct amount_sat amount_tx_fee(u32 fee_per_kw UNNEEDED, size_t weight UNNEEDED)
+{ fprintf(stderr, "amount_tx_fee called!\n"); abort(); }
 /* Generated stub for fromwire_amount_msat */
 struct amount_msat fromwire_amount_msat(const u8 **cursor UNNEEDED, size_t *max UNNEEDED)
 { fprintf(stderr, "fromwire_amount_msat called!\n"); abort(); }

cli/test/run-remove-hint.c

@@ -50,14 +50,17 @@ struct amount_sat amount_asset_to_sat(struct amount_asset *asset UNNEEDED)
 /* Generated stub for amount_sat_eq */
 bool amount_sat_eq(struct amount_sat a UNNEEDED, struct amount_sat b UNNEEDED)
 { fprintf(stderr, "amount_sat_eq called!\n"); abort(); }
-/* Generated stub for amount_sat_less */
-bool amount_sat_less(struct amount_sat a UNNEEDED, struct amount_sat b UNNEEDED)
-{ fprintf(stderr, "amount_sat_less called!\n"); abort(); }
+/* Generated stub for amount_sat_greater_eq */
+bool amount_sat_greater_eq(struct amount_sat a UNNEEDED, struct amount_sat b UNNEEDED)
+{ fprintf(stderr, "amount_sat_greater_eq called!\n"); abort(); }
 /* Generated stub for amount_sat_sub */
  bool amount_sat_sub(struct amount_sat *val UNNEEDED,
 				       struct amount_sat a UNNEEDED,
 				       struct amount_sat b UNNEEDED)
 { fprintf(stderr, "amount_sat_sub called!\n"); abort(); }
+/* Generated stub for amount_tx_fee */
+struct amount_sat amount_tx_fee(u32 fee_per_kw UNNEEDED, size_t weight UNNEEDED)
+{ fprintf(stderr, "amount_tx_fee called!\n"); abort(); }
 /* Generated stub for fromwire_amount_msat */
 struct amount_msat fromwire_amount_msat(const u8 **cursor UNNEEDED, size_t *max UNNEEDED)
 { fprintf(stderr, "fromwire_amount_msat called!\n"); abort(); }

common/json_tok.c

@@ -1,8 +1,14 @@
+#include <bitcoin/address.h>
+#include <bitcoin/base58.h>
+#include <bitcoin/chainparams.h>
+#include <bitcoin/feerate.h>
+#include <bitcoin/script.h>
 #include <ccan/crypto/sha256/sha256.h>
 #include <ccan/json_escape/json_escape.h>
 #include <ccan/str/hex/hex.h>
 #include <ccan/tal/str/str.h>
 #include <common/amount.h>
+#include <common/bech32.h>
 #include <common/channel_id.h>
 #include <common/json_command.h>
 #include <common/json_helpers.h>
@@ -330,3 +336,172 @@ struct command_result *param_secrets_array(struct command *cmd,
 	}
 	return NULL;
 }
+
+struct command_result *param_feerate_val(struct command *cmd,
+					 const char *name, const char *buffer,
+					 const jsmntok_t *tok,
+					 u32 **feerate_per_kw)
+{
+	jsmntok_t base = *tok, suffix = *tok;
+	enum feerate_style style;
+	unsigned int num;
+
+	/* We have to split the number and suffix. */
+	suffix.start = suffix.end;
+	while (suffix.start > base.start && !isdigit(buffer[suffix.start-1])) {
+		suffix.start--;
+		base.end--;
+	}
+
+	if (!json_to_number(buffer, &base, &num)) {
+		return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
+				    "'%s' prefix should be an integer, not '%.*s'",
+				    name, base.end - base.start,
+				    buffer + base.start);
+	}
+
+	if (suffix.end == suffix.start
+	    || json_tok_streq(buffer, &suffix,
+			      feerate_style_name(FEERATE_PER_KBYTE))) {
+		style = FEERATE_PER_KBYTE;
+	} else if (json_tok_streq(buffer, &suffix,
+				feerate_style_name(FEERATE_PER_KSIPA))) {
+		style = FEERATE_PER_KSIPA;
+	} else {
+		return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
+				    "'%s' suffix should be '%s' or '%s', not '%.*s'",
+				    name,
+				    feerate_style_name(FEERATE_PER_KSIPA),
+				    feerate_style_name(FEERATE_PER_KBYTE),
+				    suffix.end - suffix.start,
+				    buffer + suffix.start);
+	}
+
+	*feerate_per_kw = tal(cmd, u32);
+	**feerate_per_kw = feerate_from_style(num, style);
+	if (**feerate_per_kw < FEERATE_FLOOR)
+		**feerate_per_kw = FEERATE_FLOOR;
+	return NULL;
+}
+
+/**
+ * segwit_addr_net_decode - Try to decode a Bech32 address and detect
+ * testnet/mainnet/regtest/signet
+ *
+ * This processes the address and returns a string if it is a Bech32
+ * address specified by BIP173. The string is set whether it is
+ * testnet ("tb"),  mainnet ("bc"), regtest ("bcrt"), or signet ("sb")
+ * It does not check, witness version and program size restrictions.
+ *
+ *  Out: witness_version: Pointer to an int that will be updated to contain
+ *                 the witness program version (between 0 and 16 inclusive).
+ *       witness_program: Pointer to a buffer of size 40 that will be updated
+ *                 to contain the witness program bytes.
+ *       witness_program_len: Pointer to a size_t that will be updated to
+ *                 contain the length of bytes in witness_program.
+ *  In:  addrz:    Pointer to the null-terminated address.
+ *  Returns string containing the human readable segment of bech32 address
+ */
+static const char *segwit_addr_net_decode(int *witness_version,
+					  uint8_t *witness_program,
+					  size_t *witness_program_len,
+					  const char *addrz,
+					  const struct chainparams *chainparams)
+{
+	if (segwit_addr_decode(witness_version, witness_program,
+			       witness_program_len, chainparams->bip173_name,
+			       addrz))
+		return chainparams->bip173_name;
+	else
+		return NULL;
+}
+
+enum address_parse_result
+json_to_address_scriptpubkey(const tal_t *ctx,
+			      const struct chainparams *chainparams,
+			      const char *buffer,
+			      const jsmntok_t *tok, const u8 **scriptpubkey)
+{
+	struct bitcoin_address destination;
+	int witness_version;
+	/* segwit_addr_net_decode requires a buffer of size 40, and will
+	 * not write to the buffer if the address is too long, so a buffer
+	 * of fixed size 40 will not overflow. */
+	uint8_t witness_program[40];
+	size_t witness_program_len;
+
+	char *addrz;
+	const char *bip173;
+
+	bool parsed;
+	bool right_network;
+	u8 addr_version;
+
+	parsed =
+	    ripemd160_from_base58(&addr_version, &destination.addr,
+				  buffer + tok->start, tok->end - tok->start);
+
+	if (parsed) {
+		if (addr_version == chainparams->p2pkh_version) {
+			*scriptpubkey = scriptpubkey_p2pkh(ctx, &destination);
+			return ADDRESS_PARSE_SUCCESS;
+		} else if (addr_version == chainparams->p2sh_version) {
+			*scriptpubkey =
+			    scriptpubkey_p2sh_hash(ctx, &destination.addr);
+			return ADDRESS_PARSE_SUCCESS;
+		} else {
+			return ADDRESS_PARSE_WRONG_NETWORK;
+		}
+		/* Insert other parsers that accept pointer+len here. */
+	}
+
+	/* Generate null-terminated address. */
+	addrz = tal_dup_arr(ctx, char, buffer + tok->start, tok->end - tok->start, 1);
+	addrz[tok->end - tok->start] = '\0';
+
+	bip173 = segwit_addr_net_decode(&witness_version, witness_program,
+					&witness_program_len, addrz, chainparams);
+
+	if (bip173) {
+		bool witness_ok = false;
+		if (witness_version == 0 && (witness_program_len == 20 ||
+					     witness_program_len == 32)) {
+			witness_ok = true;
+		}
+		/* Insert other witness versions here. */
+
+		if (witness_ok) {
+			*scriptpubkey = scriptpubkey_witness_raw(ctx, witness_version,
+								 witness_program, witness_program_len);
+			parsed = true;
+			right_network = streq(bip173, chainparams->bip173_name);
+		}
+	}
+	/* Insert other parsers that accept null-terminated string here. */
+
+	tal_free(addrz);
+
+	if (parsed) {
+		if (right_network)
+			return ADDRESS_PARSE_SUCCESS;
+		else
+			return ADDRESS_PARSE_WRONG_NETWORK;
+	}
+
+	return ADDRESS_PARSE_UNRECOGNIZED;
+}
+
+struct command_result *param_txid(struct command *cmd,
+				  const char *name,
+				  const char *buffer,
+				  const jsmntok_t *tok,
+				  struct bitcoin_txid **txid)
+{
+	*txid = tal(cmd, struct bitcoin_txid);
+	if (json_to_txid(buffer, tok, *txid))
+		return NULL;
+	return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
+			    "'%s' should be txid, not '%.*s'",
+			    name, json_tok_full_len(tok),
+			    json_tok_full(buffer, tok));
+}