diff --git a/common/json.c b/common/json.c
index 162d7a625..23aab5b8b 100644
--- a/common/json.c
+++ b/common/json.c
@@ -126,14 +126,6 @@ bool json_tok_is_null(const char *buffer, const jsmntok_t *tok)
 	return buffer[tok->start] == 'n';
 }
 
-bool json_tok_sha256(const char *buffer, const jsmntok_t * tok,
-		     struct sha256 *hash)
-{
-	return hex_decode(buffer + tok->start,
-			  tok->end - tok->start,
-			  hash, sizeof(*hash));
-}
-
 const jsmntok_t *json_next(const jsmntok_t *tok)
 {
 	const jsmntok_t *t;
diff --git a/common/json.h b/common/json.h
index aa56d188b..02ef93058 100644
--- a/common/json.h
+++ b/common/json.h
@@ -39,10 +39,6 @@ bool json_to_double(const char *buffer, const jsmntok_t *tok, double *num);
 bool json_tok_bitcoin_amount(const char *buffer, const jsmntok_t *tok,
 			     uint64_t *satoshi);
 
-/* Extract sha256 hash */
-bool json_tok_sha256(const char *buffer, const jsmntok_t * tok,
-		     struct sha256 *hash);
-
 /* Is this the null primitive? */
 bool json_tok_is_null(const char *buffer, const jsmntok_t *tok);
 
diff --git a/lightningd/json.c b/lightningd/json.c
index 1d399da03..5cd46fff5 100644
--- a/lightningd/json.c
+++ b/lightningd/json.c
@@ -142,6 +142,22 @@ bool json_tok_number(struct command *cmd, const char *name,
 	return true;
 }
 
+bool json_tok_sha256(struct command *cmd, const char *name,
+		     const char *buffer, const jsmntok_t *tok,
+		     struct sha256 **hash)
+{
+	*hash = tal(cmd, struct sha256);
+	if (hex_decode(buffer + tok->start,
+		       tok->end - tok->start,
+		       *hash, sizeof(**hash)))
+		return true;
+
+	command_fail(cmd, JSONRPC2_INVALID_PARAMS,
+		     "'%s' should be a 32 byte hex value, not '%.*s'",
+		     name, tok->end - tok->start, buffer + tok->start);
+	return false;
+}
+
 bool json_tok_u64(struct command *cmd, const char *name,
 		  const char *buffer, const jsmntok_t *tok,
 		  uint64_t **num)
diff --git a/lightningd/json.h b/lightningd/json.h
index f0d526e85..23f5a5e81 100644
--- a/lightningd/json.h
+++ b/lightningd/json.h
@@ -18,6 +18,7 @@ struct command;
 struct json_result;
 struct pubkey;
 struct route_hop;
+struct sha256;
 struct short_channel_id;
 struct wallet_payment;
 struct wireaddr;
@@ -56,6 +57,11 @@ bool json_tok_number(struct command *cmd, const char *name,
 		     const char *buffer, const jsmntok_t *tok,
 		     unsigned int **num);
 
+/* Extract sha256 hash */
+bool json_tok_sha256(struct command *cmd, const char *name,
+		     const char *buffer, const jsmntok_t *tok,
+		     struct sha256 **hash);
+
 /* Extract a pubkey from this */
 bool json_tok_pubkey(const char *buffer, const jsmntok_t *tok,
 		     struct pubkey *pubkey);
diff --git a/lightningd/jsonrpc.c b/lightningd/jsonrpc.c
index 5d31d8f03..d5b6dec65 100644
--- a/lightningd/jsonrpc.c
+++ b/lightningd/jsonrpc.c
@@ -96,17 +96,17 @@ static void json_rhash(struct command *cmd,
 		       const char *buffer, const jsmntok_t *params)
 {
 	struct json_result *response = new_json_result(cmd);
-	struct sha256 secret;
+	struct sha256 *secret;
 
 	if (!param(cmd, buffer, params,
-		   p_req("secret", json_tok_sha256, &secret),
+		   p_req_tal("secret", json_tok_sha256, &secret),
 		   NULL))
 		return;
 
 	/* Hash in place. */
-	sha256(&secret, &secret, sizeof(secret));
+	sha256(secret, secret, sizeof(*secret));
 	json_object_start(response, NULL);
-	json_add_hex(response, "rhash", &secret, sizeof(secret));
+	json_add_hex(response, "rhash", secret, sizeof(*secret));
 	json_object_end(response);
 	command_success(cmd, response);
 }
diff --git a/lightningd/param.c b/lightningd/param.c
index 73852bf9d..b371bc0ad 100644
--- a/lightningd/param.c
+++ b/lightningd/param.c
@@ -53,7 +53,6 @@ static struct fail_format fail_formats[] = {
 	{json_tok_wtx,
 	 "'%s' should be 'all' or a positive integer greater than "
 	 "545, not '%.*s'"},
-	{json_tok_sha256, "'%s' should be a 32 byte hex value, not '%.*s'"},
 	{NULL, "'%s' of '%.*s' is invalid'"}
 };
 
diff --git a/lightningd/pay.c b/lightningd/pay.c
index 57e3fc0c3..fd41c271e 100644
--- a/lightningd/pay.c
+++ b/lightningd/pay.c
@@ -948,7 +948,7 @@ static void json_sendpay(struct command *cmd,
 	const jsmntok_t *routetok, *desctok;
 	const jsmntok_t *t, *end;
 	size_t n_hops;
-	struct sha256 rhash;
+	struct sha256 *rhash;
 	struct route_hop *route;
 	u64 *msatoshi;
 	const struct json_escaped *desc;
@@ -956,7 +956,7 @@ static void json_sendpay(struct command *cmd,
 
 	if (!param(cmd, buffer, params,
 		   p_req_tal("route", json_tok_tok, &routetok),
-		   p_req("payment_hash", json_tok_sha256, &rhash),
+		   p_req_tal("payment_hash", json_tok_sha256, &rhash),
 		   p_opt_tal("description", json_tok_tok, &desctok),
 		   p_opt_tal("msatoshi", json_tok_u64, &msatoshi),
 		   NULL))
@@ -1068,7 +1068,7 @@ static void json_sendpay(struct command *cmd,
 		description = NULL;
 	}
 
-	if (send_payment(cmd, cmd->ld, &rhash, route,
+	if (send_payment(cmd, cmd->ld, rhash, route,
 			 msatoshi ? *msatoshi : route[n_hops-1].amount,
 			 description,
 			 &json_sendpay_on_resolve, cmd))
@@ -1090,16 +1090,16 @@ static void waitsendpay_timeout(struct command *cmd)
 static void json_waitsendpay(struct command *cmd, const char *buffer,
 			     const jsmntok_t *params)
 {
-	struct sha256 rhash;
+	struct sha256 *rhash;
 	unsigned int *timeout;
 
 	if (!param(cmd, buffer, params,
-		   p_req("payment_hash", json_tok_sha256, &rhash),
+		   p_req_tal("payment_hash", json_tok_sha256, &rhash),
 		   p_opt_tal("timeout", json_tok_number, &timeout),
 		   NULL))
 		return;
 
-	if (!wait_payment(cmd, cmd->ld, &rhash, &json_waitsendpay_on_resolve, cmd))
+	if (!wait_payment(cmd, cmd->ld, rhash, &json_waitsendpay_on_resolve, cmd))
 		return;
 
 	if (timeout)