rpcd-mod-luci: handle lease files from all dnsmasq/odhcpd sections

Fixes: #911, #4303, #4308
Signed-off-by: Jo-Philipp Wich <jo@mein.io>

1 files changed, 134 insertions, 111 deletions

diff --git a/libs/rpcd-mod-luci/src/luci.c b/libs/rpcd-mod-luci/src/luci.c
index 1a1524d49e..94ccdf2716 100644
--- a/libs/rpcd-mod-luci/src/luci.c
+++ b/libs/rpcd-mod-luci/src/luci.c
@@ -315,9 +315,12 @@ duid2ea(const char *duid)
 
 
 static struct {
-	FILE *dnsmasq_file;
-	FILE *odhcpd_file;
 	time_t now;
+	size_t num, off;
+	struct {
+		FILE *fh;
+		bool odhcpd;
+	} *files;
 } lease_state = { };
 
 struct lease_entry {
@@ -333,13 +336,41 @@ struct lease_entry {
 	} addr[10];
 };
 
-static char *
-find_leasefile(struct uci_context *uci, const char *section)
+static bool
+add_leasefile(const char *path, bool is_odhcpd)
+{
+	void *ptr;
+	FILE *fh;
+
+	fh = fopen(path, "r");
+
+	if (!fh)
+		return false;
+
+	ptr = realloc(lease_state.files, sizeof(*lease_state.files) * (lease_state.num + 1));
+
+	if (!ptr) {
+		fclose(fh);
+
+		return false;
+	}
+
+	lease_state.files = ptr;
+	lease_state.files[lease_state.num].fh = fh;
+	lease_state.files[lease_state.num].odhcpd = is_odhcpd;
+	lease_state.num++;
+
+	return true;
+}
+
+static bool
+find_leasefiles(struct uci_context *uci, bool is_odhcpd)
 {
 	struct uci_ptr ptr = { .package = "dhcp" };
 	struct uci_package *pkg = NULL;
 	struct uci_section *s;
 	struct uci_element *e;
+	bool found = false;
 
 	pkg = uci_lookup_package(uci, ptr.package);
 
@@ -353,7 +384,7 @@ find_leasefile(struct uci_context *uci, const char *section)
 	uci_foreach_element(&pkg->sections, e) {
 		s = uci_to_section(e);
 
-		if (strcmp(s->type, section))
+		if (strcmp(s->type, is_odhcpd ? "odhcpd" : "dnsmasq"))
 			continue;
 
 		ptr.flags = 0;
@@ -370,31 +401,30 @@ find_leasefile(struct uci_context *uci, const char *section)
 		if (ptr.o->type != UCI_TYPE_STRING)
 			continue;
 
-		return ptr.o->v.string;
+		if (add_leasefile(ptr.o->v.string, is_odhcpd))
+			found = true;
 	}
 
-	return NULL;
+	return found;
 }
 
 static void
 lease_close(void)
 {
-	if (lease_state.dnsmasq_file) {
-		fclose(lease_state.dnsmasq_file);
-		lease_state.dnsmasq_file = NULL;
-	}
+	while (lease_state.num > 0)
+		fclose(lease_state.files[--lease_state.num].fh);
 
-	if (lease_state.odhcpd_file) {
-		fclose(lease_state.odhcpd_file);
-		lease_state.odhcpd_file = NULL;
-	}
+	free(lease_state.files);
+
+	lease_state.files = NULL;
+	lease_state.num = 0;
+	lease_state.off = 0;
 }
 
 static void
 lease_open(void)
 {
 	struct uci_context *uci;
-	char *p;
 
 	lease_close();
 
@@ -405,11 +435,11 @@ lease_open(void)
 
 	lease_state.now = time(NULL);
 
-	p = find_leasefile(uci, "dnsmasq");
-	lease_state.dnsmasq_file = fopen(p ? p : "/tmp/dhcp.leases", "r");
+	if (!find_leasefiles(uci, false))
+		add_leasefile("/tmp/dhcp.leases", false);
 
-	p = find_leasefile(uci, "odhcpd");
-	lease_state.odhcpd_file = fopen(p ? p : "/tmp/hosts/odhcpd", "r");
+	if (!find_leasefiles(uci, true))
+		add_leasefile("/tmp/hosts/odhcpd", true);
 
 	uci_free_context(uci);
 }
@@ -424,133 +454,126 @@ lease_next(void)
 
 	memset(&e, 0, sizeof(e));
 
-	if (lease_state.dnsmasq_file) {
-		while (fgets(e.buf, sizeof(e.buf), lease_state.dnsmasq_file)) {
-			p = strtok(e.buf, " \t\n");
+	while (lease_state.off < lease_state.num) {
+		while (fgets(e.buf, sizeof(e.buf), lease_state.files[lease_state.off].fh)) {
+			if (lease_state.files[lease_state.off].odhcpd) {
+				strtok(e.buf, " \t\n"); /* # */
+				strtok(NULL, " \t\n"); /* iface */
 
-			if (!p)
-				continue;
+				e.duid = strtok(NULL, " \t\n"); /* duid */
 
-			n = strtol(p, NULL, 10);
+				if (!e.duid)
+					continue;
 
-			if (n > lease_state.now)
-				e.expire = n - lease_state.now;
-			else if (n > 0)
-				e.expire = 0;
-			else
-				e.expire = -1;
+				p = strtok(NULL, " \t\n"); /* iaid */
 
-			p = strtok(NULL, " \t\n");
+				if (p)
+					e.af = strcmp(p, "ipv4") ? AF_INET6 : AF_INET;
+				else
+					continue;
 
-			if (!p)
-				continue;
+				e.hostname = strtok(NULL, " \t\n"); /* name */
 
-			ea = ether_aton(p);
+				if (!e.hostname)
+					continue;
 
-			p = strtok(NULL, " \t\n");
+				p = strtok(NULL, " \t\n"); /* ts */
 
-			if (p && inet_pton(AF_INET6, p, &e.addr[0].in6)) {
-				e.af = AF_INET6;
-				e.n_addr = 1;
-			}
-			else if (p && inet_pton(AF_INET, p, &e.addr[0].in)) {
-				e.af = AF_INET;
-				e.n_addr = 1;
-			}
-			else {
-				continue;
-			}
-
-			if (!ea && e.af != AF_INET6)
-				continue;
+				if (!p)
+					continue;
 
-			e.hostname = strtok(NULL, " \t\n");
-			e.duid     = strtok(NULL, " \t\n");
+				n = strtol(p, NULL, 10);
 
-			if (!e.hostname || !e.duid)
-				continue;
+				if (n > lease_state.now)
+					e.expire = n - lease_state.now;
+				else if (n >= 0)
+					e.expire = 0;
+				else
+					e.expire = -1;
 
-			if (!strcmp(e.hostname, "*"))
-				e.hostname = NULL;
+				strtok(NULL, " \t\n"); /* id */
+				strtok(NULL, " \t\n"); /* length */
 
-			if (!strcmp(e.duid, "*"))
-				e.duid = NULL;
+				for (e.n_addr = 0, p = strtok(NULL, "/ \t\n");
+				     e.n_addr < ARRAY_SIZE(e.addr) && p != NULL;
+				     p = strtok(NULL, "/ \t\n")) {
+					if (inet_pton(e.af, p, &e.addr[e.n_addr].in6))
+						e.n_addr++;
+				}
 
-			if (!ea && e.duid)
 				ea = duid2ea(e.duid);
 
-			if (ea)
-				e.mac = *ea;
+				if (ea)
+					e.mac = *ea;
 
-			return &e;
-		}
+				if (!strcmp(e.hostname, "-"))
+					e.hostname = NULL;
 
-		fclose(lease_state.dnsmasq_file);
-		lease_state.dnsmasq_file = NULL;
-	}
+				if (!strcmp(e.duid, "-"))
+					e.duid = NULL;
+			}
+			else {
+				p = strtok(e.buf, " \t\n");
 
-	if (lease_state.odhcpd_file) {
-		while (fgets(e.buf, sizeof(e.buf), lease_state.odhcpd_file)) {
-			strtok(e.buf, " \t\n"); /* # */
-			strtok(NULL, " \t\n"); /* iface */
+				if (!p)
+					continue;
 
-			e.duid = strtok(NULL, " \t\n"); /* duid */
+				n = strtol(p, NULL, 10);
 
-			if (!e.duid)
-				continue;
+				if (n > lease_state.now)
+					e.expire = n - lease_state.now;
+				else if (n > 0)
+					e.expire = 0;
+				else
+					e.expire = -1;
 
-			p = strtok(NULL, " \t\n"); /* iaid */
+				p = strtok(NULL, " \t\n");
 
-			if (p)
-				e.af = strcmp(p, "ipv4") ? AF_INET6 : AF_INET;
-			else
-				continue;
-
-			e.hostname = strtok(NULL, " \t\n"); /* name */
-
-			if (!e.hostname)
-				continue;
+				if (!p)
+					continue;
 
-			p = strtok(NULL, " \t\n"); /* ts */
+				ea = ether_aton(p);
 
-			if (!p)
-				continue;
+				p = strtok(NULL, " \t\n");
 
-			n = strtol(p, NULL, 10);
+				if (p && inet_pton(AF_INET6, p, &e.addr[0].in6)) {
+					e.af = AF_INET6;
+					e.n_addr = 1;
+				}
+				else if (p && inet_pton(AF_INET, p, &e.addr[0].in)) {
+					e.af = AF_INET;
+					e.n_addr = 1;
+				}
+				else {
+					continue;
+				}
 
-			if (n > lease_state.now)
-				e.expire = n - lease_state.now;
-			else if (n >= 0)
-				e.expire = 0;
-			else
-				e.expire = -1;
+				if (!ea && e.af != AF_INET6)
+					continue;
 
-			strtok(NULL, " \t\n"); /* id */
-			strtok(NULL, " \t\n"); /* length */
+				e.hostname = strtok(NULL, " \t\n");
+				e.duid     = strtok(NULL, " \t\n");
 
-			for (e.n_addr = 0, p = strtok(NULL, "/ \t\n");
-			     e.n_addr < ARRAY_SIZE(e.addr) && p != NULL;
-			     p = strtok(NULL, "/ \t\n")) {
-				if (inet_pton(e.af, p, &e.addr[e.n_addr].in6))
-					e.n_addr++;
-			}
+				if (!e.hostname || !e.duid)
+					continue;
 
-			ea = duid2ea(e.duid);
+				if (!strcmp(e.hostname, "*"))
+					e.hostname = NULL;
 
-			if (ea)
-				e.mac = *ea;
+				if (!strcmp(e.duid, "*"))
+					e.duid = NULL;
 
-			if (!strcmp(e.hostname, "-"))
-				e.hostname = NULL;
+				if (!ea && e.duid)
+					ea = duid2ea(e.duid);
 
-			if (!strcmp(e.duid, "-"))
-				e.duid = NULL;
+				if (ea)
+					e.mac = *ea;
+			}
 
 			return &e;
 		}
 
-		fclose(lease_state.odhcpd_file);
-		lease_state.odhcpd_file = NULL;
+		lease_state.off++;
 	}
 
 	return NULL;