json-rpc: Remove upper limit for percentage

The `json_tok_percentage` parser is used for the `fuzzpercent` in `getroute` and
`maxfeepercent` in `pay`. In both cases it seems reasonable to allow values
larger than 100%. This has bitten users in the past when they transferred single
satoshis to things like satoshis.place over a route longer than 2 hops.

lightningd/gossip_control.c

@@ -327,7 +327,7 @@ static const struct json_command getroute_command = {
 	json_getroute,
 	"Show route to {id} for {msatoshi}, using {riskfactor} and optional {cltv} (default 9). "
 	"If specified search from {fromid} otherwise use this node as source. "
-	"Randomize the route with up to {fuzzpercent} (0.0 -> 100.0, default 5.0) "
+	"Randomize the route with up to {fuzzpercent} (default 5.0) "
 	"using {seed} as an arbitrary-size string seed."
 };
 AUTODATA(json_command, &getroute_command);

lightningd/json.c

@@ -238,12 +238,11 @@ bool json_tok_percent(struct command *cmd, const char *name,
 		      double **num)
 {
 	*num = tal(cmd, double);
-	if (json_to_double(buffer, tok, *num))
+	if (json_to_double(buffer, tok, *num) && **num >= 0.0)
-		if (**num >= 0.0 && **num <= 100.0)
 		return true;
 
 	command_fail(cmd, JSONRPC2_INVALID_PARAMS,
-		     "'%s' should be a double in range [0.0, 100.0], not '%.*s'",
+		     "'%s' should be a positive double, not '%.*s'",
 		     name, tok->end - tok->start, buffer + tok->start);
 	return false;
 }

lightningd/test/run-param.c

@@ -502,8 +502,8 @@ static void json_tok_tests(void)
 	test_cb(json_tok_percent, double, "[ 1.01 ]", 1.01, true);
 	test_cb(json_tok_percent, double, "[ 99.99 ]", 99.99, true);
 	test_cb(json_tok_percent, double, "[ 100.0 ]", 100, true);
-	test_cb(json_tok_percent, double, "[ 100.001 ]", 0, false);
+	test_cb(json_tok_percent, double, "[ 100.001 ]", 100.001, true);
-	test_cb(json_tok_percent, double, "[ 1000 ]", 0, false);
+	test_cb(json_tok_percent, double, "[ 1000 ]", 1000, true);
 	test_cb(json_tok_percent, double, "[ 'wow' ]", 0, false);
 }