From 8f27697b9b82420890cedd429622052c8b67cea1 Mon Sep 17 00:00:00 2001
From: Santiago Piccinini <spiccinini@altermundi.net>
Date: Wed, 2 Dec 2020 19:07:05 -0300
Subject: [PATCH] ubus: add add_lease method

Allows sharing leases between odhcpd instances running
in multiple hosts.

Signed-off-by: Santiago Piccinini <spiccinini@altermundi.net>
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>
---
 src/config.c | 29 +++++++++++++----------------
 src/odhcpd.h | 11 +++++++++++
 src/ubus.c   | 10 ++++++++++
 3 files changed, 34 insertions(+), 16 deletions(-)

diff --git a/src/config.c b/src/config.c
index 8a6f573..95b745c 100644
--- a/src/config.c
+++ b/src/config.c
@@ -144,17 +144,7 @@ const struct uci_blob_param_list interface_attr_list = {
 	.info = iface_attr_info,
 };
 
-enum {
-	LEASE_ATTR_IP,
-	LEASE_ATTR_MAC,
-	LEASE_ATTR_DUID,
-	LEASE_ATTR_HOSTID,
-	LEASE_ATTR_LEASETIME,
-	LEASE_ATTR_NAME,
-	LEASE_ATTR_MAX
-};
-
-static const struct blobmsg_policy lease_attrs[LEASE_ATTR_MAX] = {
+const struct blobmsg_policy lease_attrs[LEASE_ATTR_MAX] = {
 	[LEASE_ATTR_IP] = { .name = "ip", .type = BLOBMSG_TYPE_STRING },
 	[LEASE_ATTR_MAC] = { .name = "mac", .type = BLOBMSG_TYPE_STRING },
 	[LEASE_ATTR_DUID] = { .name = "duid", .type = BLOBMSG_TYPE_STRING },
@@ -387,16 +377,15 @@ static void free_lease(struct lease *l)
 	free(l);
 }
 
-static int set_lease(struct uci_section *s)
+
+int set_lease_from_blobmsg(struct blob_attr *ba)
 {
 	struct blob_attr *tb[LEASE_ATTR_MAX], *c;
 	struct lease *l;
 	size_t duidlen = 0;
 	uint8_t *duid;
 
-	blob_buf_init(&b, 0);
-	uci_to_blob(&b, s, &lease_attr_list);
-	blobmsg_parse(lease_attrs, LEASE_ATTR_MAX, tb, blob_data(b.head), blob_len(b.head));
+	blobmsg_parse(lease_attrs, LEASE_ATTR_MAX, tb, blob_data(ba), blob_len(ba));
 
 	if ((c = tb[LEASE_ATTR_DUID]))
 		duidlen = (blobmsg_data_len(c) - 1) / 2;
@@ -460,6 +449,14 @@ err:
 	return -1;
 }
 
+static int set_lease_from_uci(struct uci_section *s)
+{
+	blob_buf_init(&b, 0);
+	uci_to_blob(&b, s, &lease_attr_list);
+
+	return set_lease_from_blobmsg(b.head);
+}
+
 int config_parse_interface(void *data, size_t len, const char *name, bool overwrite)
 {
 	struct interface *iface;
@@ -1072,7 +1069,7 @@ void odhcpd_reload(void)
 		uci_foreach_element(&dhcp->sections, e) {
 			struct uci_section* s = uci_to_section(e);
 			if (!strcmp(s->type, "host"))
-				set_lease(s);
+				set_lease_from_uci(s);
 		}
 	}
 
diff --git a/src/odhcpd.h b/src/odhcpd.h
index 0108af1..2f7dd25 100644
--- a/src/odhcpd.h
+++ b/src/odhcpd.h
@@ -159,6 +159,15 @@ struct lease {
 	char *hostname;
 };
 
+enum {
+	LEASE_ATTR_IP,
+	LEASE_ATTR_MAC,
+	LEASE_ATTR_DUID,
+	LEASE_ATTR_HOSTID,
+	LEASE_ATTR_LEASETIME,
+	LEASE_ATTR_NAME,
+	LEASE_ATTR_MAX
+};
 
 struct odhcpd_ref_ip;
 
@@ -315,6 +324,7 @@ struct interface {
 };
 
 extern struct avl_tree interfaces;
+extern const struct blobmsg_policy lease_attrs[LEASE_ATTR_MAX];
 
 inline static void free_assignment(struct dhcp_assignment *a)
 {
@@ -375,6 +385,7 @@ struct lease *config_find_lease_by_duid(const uint8_t *duid, const uint16_t len)
 struct lease *config_find_lease_by_mac(const uint8_t *mac);
 struct lease *config_find_lease_by_hostid(const uint32_t hostid);
 struct lease *config_find_lease_by_ipaddr(const uint32_t ipaddr);
+int set_lease_from_blobmsg(struct blob_attr *ba);
 
 #ifdef WITH_UBUS
 int ubus_init(void);
diff --git a/src/ubus.c b/src/ubus.c
index 72d47c4..ebc3103 100644
--- a/src/ubus.c
+++ b/src/ubus.c
@@ -174,10 +174,20 @@ static int handle_dhcpv6_leases(_unused struct ubus_context *ctx, _unused struct
 	return 0;
 }
 
+static int handle_add_lease(_unused struct ubus_context *ctx, _unused struct ubus_object *obj,
+		_unused struct ubus_request_data *req, _unused const char *method,
+		struct blob_attr *msg)
+{
+	if (!set_lease_from_blobmsg(msg))
+		return UBUS_STATUS_OK;
+
+	return UBUS_STATUS_INVALID_ARGUMENT;
+}
 
 static struct ubus_method main_object_methods[] = {
 	{.name = "ipv4leases", .handler = handle_dhcpv4_leases},
 	{.name = "ipv6leases", .handler = handle_dhcpv6_leases},
+	UBUS_METHOD("add_lease", handle_add_lease, lease_attrs),
 };
 
 static struct ubus_object_type main_object_type =
-- 
2.30.2