From: Alan T. DeKok <aland@freeradius.org>
Date: Fri, 26 Jan 2024 16:35:16 +0000 (-0500)
Subject: add foreign decoder for RADIUS and DHCPv4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0481c9587e3fbb997211981f17b37ef323e168c8;p=thirdparty%2Ffreeradius-server.git

add foreign decoder for RADIUS and DHCPv4
---

diff --git a/share/dictionary/radius/dictionary.rfc9445 b/share/dictionary/radius/dictionary.rfc9445
index b64b37367ed..e1745e25144 100644
--- a/share/dictionary/radius/dictionary.rfc9445
+++ b/share/dictionary/radius/dictionary.rfc9445
@@ -9,4 +9,4 @@
 #	$Id$
 #
 ATTRIBUTE	DHCPv6-Options				245.3	octets # formatted as DHCPv6 options
-ATTRIBUTE	DHCPv4-Options				245.4	octets # formatted as DHCPv4 options
+ATTRIBUTE	DHCPv4-Options				245.4	group ref=..DHCPv4
diff --git a/src/protocols/dhcpv4/base.c b/src/protocols/dhcpv4/base.c
index bff36f50b05..589def994b5 100644
--- a/src/protocols/dhcpv4/base.c
+++ b/src/protocols/dhcpv4/base.c
@@ -734,4 +734,5 @@ fr_dict_protocol_t libfreeradius_dhcpv4_dict_protocol = {
 	.subtype_table_len = NUM_ELEMENTS(subtype_table),
 	.attr_valid = attr_valid,
 	.encode		= fr_dhcpv4_encode_foreign,
+	.decode		= fr_dhcpv4_decode_foreign,
 };
diff --git a/src/protocols/dhcpv4/decode.c b/src/protocols/dhcpv4/decode.c
index 95665c0a261..bf7ab0e8427 100644
--- a/src/protocols/dhcpv4/decode.c
+++ b/src/protocols/dhcpv4/decode.c
@@ -637,6 +637,44 @@ ssize_t fr_dhcpv4_decode_option(TALLOC_CTX *ctx, fr_pair_list_t *out,
 	return data[1] + 2;
 }
 
+ssize_t	fr_dhcpv4_decode_foreign(TALLOC_CTX *ctx, fr_pair_list_t *out,
+				 uint8_t const *data, size_t data_len)
+{
+	ssize_t slen;
+	uint8_t const *attr, *end;
+
+	fr_dhcpv4_ctx_t decode_ctx = {};
+
+	decode_ctx.tmp_ctx = talloc(ctx, uint8_t);
+
+	attr = data;
+	end = data + data_len;
+
+	while (attr < end) {
+		slen = fr_dhcpv4_decode_option(ctx, out, attr, (end - attr), &decode_ctx);
+		if (slen < 0) {
+			talloc_free(decode_ctx.tmp_ctx);
+			return slen - (attr - data);
+		}
+
+		/*
+		 *	If slen is larger than the room in the packet,
+		 *	all kinds of bad things happen.
+		 */
+		 if (!fr_cond_assert(slen <= (end - attr))) {
+			talloc_free(decode_ctx.tmp_ctx);
+			 return -slen - (attr - data);
+		 }
+
+		attr += slen;
+		talloc_free_children(decode_ctx.tmp_ctx);
+	}
+
+	talloc_free(decode_ctx.tmp_ctx);
+	return data_len;
+}
+
+
 static int _decode_test_ctx(UNUSED fr_dhcpv4_ctx_t *test_ctx)
 {
 	fr_dhcpv4_global_free();
diff --git a/src/protocols/dhcpv4/dhcpv4.h b/src/protocols/dhcpv4/dhcpv4.h
index 965989216e6..4a1a5ecbad2 100644
--- a/src/protocols/dhcpv4/dhcpv4.h
+++ b/src/protocols/dhcpv4/dhcpv4.h
@@ -177,6 +177,9 @@ void		fr_dhcpv4_print_hex(FILE *fp, uint8_t const *packet, size_t packet_len);
 ssize_t		fr_dhcpv4_decode_option(TALLOC_CTX *ctx, fr_pair_list_t *out,
 					uint8_t const *data, size_t len, void *decode_ctx) CC_HINT(nonnull);
 
+ssize_t		fr_dhcpv4_decode_foreign(TALLOC_CTX *ctx, fr_pair_list_t *out,
+					 uint8_t const *data, size_t data_len) CC_HINT(nonnull);
+
 /*
  *	encode.c
  */
diff --git a/src/protocols/radius/decode.c b/src/protocols/radius/decode.c
index 6aaf3116627..ec77f9fa793 100644
--- a/src/protocols/radius/decode.c
+++ b/src/protocols/radius/decode.c
@@ -1780,6 +1780,33 @@ ssize_t fr_radius_decode_pair_value(TALLOC_CTX *ctx, fr_pair_list_t *out,
 		if (ret < 0) goto raw;
 		return attr_len;
 
+	case FR_TYPE_GROUP:
+	{
+		fr_dict_attr_t const *ref;
+		fr_dict_protocol_t const *proto;
+
+		ref = fr_dict_attr_ref(parent);
+		if (!ref) goto raw;
+
+		fr_assert(ref->dict != parent->dict);
+
+		proto = fr_dict_protocol(ref->dict);
+		fr_assert(proto != NULL);
+
+		if (!proto->decode) goto raw;
+
+		vp = fr_pair_afrom_da(ctx, parent);
+		if (!vp) return -1;
+
+		ret = proto->decode(vp, &vp->vp_group, p, attr_len);
+		if (ret < 0) goto raw;
+
+		vp->vp_tainted = true;
+
+		fr_pair_append(out, vp);
+		return attr_len;
+	}
+
 	default:
 	raw:
 		if (vp) talloc_free(vp);
diff --git a/src/tests/unit/protocols/radius/foreign.txt b/src/tests/unit/protocols/radius/foreign.txt
new file mode 100644
index 00000000000..861ce8af85d
--- /dev/null
+++ b/src/tests/unit/protocols/radius/foreign.txt
@@ -0,0 +1,12 @@
+proto radius
+proto-dictionary radius
+fuzzer-out radius
+
+encode-pair Extended-Attribute-5.DHCPv4-Options := { Time-Offset = 2112 }
+match f5 0a 04 00 02 04 00 00 08 40
+
+decode-pair -
+match Extended-Attribute-5 = { DHCPv4-Options = { Time-Offset = 2112 } }
+
+count
+match 7