From: Arran Cudbard-Bell <a.cudbardb@freeradius.org>
Date: Fri, 25 Oct 2024 05:20:36 +0000 (-0600)
Subject: Switch DHCPv6 to using custom flag parsers
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e7693e8454140c70bfee442ef8c607f70ecf066b;p=thirdparty%2Ffreeradius-server.git

Switch DHCPv6 to using custom flag parsers
---

diff --git a/src/protocols/dhcpv6/base.c b/src/protocols/dhcpv6/base.c
index 9c578ba01c3..6a408193941 100644
--- a/src/protocols/dhcpv6/base.c
+++ b/src/protocols/dhcpv6/base.c
@@ -107,9 +107,12 @@ char const *fr_dhcpv6_packet_names[FR_DHCPV6_CODE_MAX] = {
 	 [FR_PACKET_TYPE_VALUE_CONTACT]			= "Contact"
 };
 
-static fr_table_num_ordered_t const subtype_table[] = {
-	{ L("dns_label"),			FLAG_ENCODE_DNS_LABEL },
-	{ L("partial_dns_label"), 		FLAG_ENCODE_PARTIAL_DNS_LABEL }
+FR_DICT_ATTR_FLAG_FUNC(fr_dhcpv6_attr_flags_t, dns_label)
+FR_DICT_ATTR_FLAG_FUNC(fr_dhcpv6_attr_flags_t, partial_dns_label)
+
+static fr_dict_flag_parser_t const dhcpv6_flags[] = {
+	{ L("dns_label"),		{ .func = dict_flag_dns_label } },
+	{ L("partial_dns_label"),	{ .func = dict_flag_partial_dns_label } }
 };
 
 static ssize_t fr_dhcpv6_ok_internal(uint8_t const *packet, uint8_t const *end, size_t max_attributes, int depth);
@@ -970,7 +973,7 @@ static bool attr_valid(fr_dict_attr_t *da)
 	 */
 	if (da->flags.extra || !da->flags.subtype) return true;
 
-	if ((da->type != FR_TYPE_STRING) && ((da->flags.subtype == FLAG_ENCODE_DNS_LABEL) || (da->flags.subtype == FLAG_ENCODE_PARTIAL_DNS_LABEL))) {
+	if ((da->type != FR_TYPE_STRING) && fr_dhcpv6_flag_any_dns_label(da)) {
 		fr_strerror_const("The 'dns_label' flag can only be used with attributes of type 'string'");
 		return false;
 	}
@@ -985,10 +988,12 @@ fr_dict_protocol_t libfreeradius_dhcpv6_dict_protocol = {
 	.name = "dhcpv6",
 	.default_type_size = 2,
 	.default_type_length = 2,
-	.subtype_table = subtype_table,
-	.subtype_table_len = NUM_ELEMENTS(subtype_table),
+
 	.attr = {
 		.valid = attr_valid,
+		.flags_table = dhcpv6_flags,
+		.flags_table_len = NUM_ELEMENTS(dhcpv6_flags),
+		.flags_len = sizeof(fr_dhcpv6_attr_flags_t)
 	},
 
 	.init = fr_dhcpv6_global_init,
diff --git a/src/protocols/dhcpv6/decode.c b/src/protocols/dhcpv6/decode.c
index 5840ef16ade..e7ed490dfb1 100644
--- a/src/protocols/dhcpv6/decode.c
+++ b/src/protocols/dhcpv6/decode.c
@@ -58,7 +58,7 @@ static ssize_t decode_value_trampoline(TALLOC_CTX *ctx, fr_pair_list_t *out,
 				       fr_dict_attr_t const *parent,
 				       uint8_t const *data, size_t const data_len, void *decode_ctx)
 {
-	if ((parent->type == FR_TYPE_STRING) && da_is_dns_label(parent)) {
+	if ((parent->type == FR_TYPE_STRING) && fr_dhcpv6_flag_any_dns_label(parent)) {
 		return fr_pair_dns_labels_from_network(ctx, out, parent, data, data, data_len, NULL, false);
 	}
 
@@ -369,7 +369,7 @@ static ssize_t decode_option(TALLOC_CTX *ctx, fr_pair_list_t *out,
 
 		fr_pair_append(out, vp);
 
-	} else if ((da->type == FR_TYPE_STRING) && da_is_dns_label(da)) {
+	} else if ((da->type == FR_TYPE_STRING) && fr_dhcpv6_flag_any_dns_label(da)) {
 		slen = fr_pair_dns_labels_from_network(ctx, out, da, data + 4, data + 4, len, NULL, true);
 		if (slen < 0) return slen;
 
diff --git a/src/protocols/dhcpv6/dhcpv6.h b/src/protocols/dhcpv6/dhcpv6.h
index b9484cc5a4e..c8eb3e6c090 100644
--- a/src/protocols/dhcpv6/dhcpv6.h
+++ b/src/protocols/dhcpv6/dhcpv6.h
@@ -111,14 +111,6 @@ extern char const		*fr_dhcpv6_packet_names[FR_DHCPV6_CODE_MAX];
 /** subtype values for DHCPv4 and DHCPv6
  *
  */
-enum {
-	FLAG_ENCODE_NONE = 0,				//!< no particular encoding for DHCPv6 strings
-	FLAG_ENCODE_DNS_LABEL,				//!< encode as DNS label
-	FLAG_ENCODE_PARTIAL_DNS_LABEL, 			//!< encode as a partial DNS label
-};
-
-#define da_is_dns_label(_da) (!(_da)->flags.extra && (((_da)->flags.subtype == FLAG_ENCODE_DNS_LABEL) || ((_da)->flags.subtype == FLAG_ENCODE_PARTIAL_DNS_LABEL)))
-
 typedef struct CC_HINT(__packed__) {
 	uint8_t		code;
 	uint8_t		transaction_id[3];
@@ -144,6 +136,26 @@ typedef struct {
 	size_t			duid_len;		//!< length of the expected DUID
 } fr_dhcpv6_decode_ctx_t;
 
+typedef struct {
+	bool			dns_label;
+	bool			partial_dns_label;
+} fr_dhcpv6_attr_flags_t;
+
+static inline fr_dhcpv6_attr_flags_t const *fr_dhcpv6_attr_flags(fr_dict_attr_t const *da)
+{
+	return fr_dict_attr_ext(da, FR_DICT_ATTR_EXT_PROTOCOL_SPECIFIC);
+}
+
+#define fr_dhcpv6_flag_dns_label(_da)			(fr_dhcpv6_attr_flags(_da)->dns_label)
+#define fr_dhcpv6_flag_partial_dns_label(_da)		(fr_dhcpv6_attr_flags(_da)->partial_dns_label)
+
+static inline bool fr_dhcpv6_flag_any_dns_label(fr_dict_attr_t const *da)
+{
+	fr_dhcpv6_attr_flags_t const *flags = fr_dhcpv6_attr_flags(da);
+
+	return flags->dns_label || flags->partial_dns_label;
+}
+
 /*
  *	base.c
  */
diff --git a/src/protocols/dhcpv6/encode.c b/src/protocols/dhcpv6/encode.c
index 8a502a4c80f..c78dd365d22 100644
--- a/src/protocols/dhcpv6/encode.c
+++ b/src/protocols/dhcpv6/encode.c
@@ -140,7 +140,7 @@ static ssize_t encode_value(fr_dbuff_t *dbuff,
 		 *
 		 *	https://tools.ietf.org/html/rfc8415#section-10
 		 */
-		if (da_is_dns_label(da)) {
+		if (fr_dhcpv6_flag_any_dns_label(da)) {
 			fr_dbuff_marker_t	last_byte, src;
 
 			fr_dbuff_marker(&last_byte, &work_dbuff);
@@ -154,7 +154,7 @@ static ssize_t encode_value(fr_dbuff_t *dbuff,
 			 *	partial name, and we omit the trailing
 			 *	zero.
 			 */
-			if ((da->flags.subtype == FLAG_ENCODE_PARTIAL_DNS_LABEL) && slen > 0) {
+			if (fr_dhcpv6_flag_partial_dns_label(da) && slen > 0) {
 				uint8_t c = 0;
 
 				fr_dbuff_advance(&last_byte, (size_t)(slen - 1));