From: Alan T. DeKok <aland@freeradius.org>
Date: Fri, 18 Mar 2022 00:05:49 +0000 (-0400)
Subject: one more stupid format for IPv4 prefixes
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4c531e34d69878982cdeeda54d82a4e200277019;p=thirdparty%2Ffreeradius-server.git

one more stupid format for IPv4 prefixes
---

diff --git a/share/dictionary/dhcpv4/dictionary b/share/dictionary/dhcpv4/dictionary
index f60b711ad4b..3b50828e7fa 100644
--- a/share/dictionary/dhcpv4/dictionary
+++ b/share/dictionary/dhcpv4/dictionary
@@ -24,6 +24,7 @@ $INCLUDE dictionary.freeradius.internal
 # Fixme should be broken out into separate RFCs
 $INCLUDE dictionary.rfc2131
 $INCLUDE dictionary.rfc2610
+$INCLUDE dictionary.rfc3442
 $INCLUDE dictionary.rfc4280
 $INCLUDE dictionary.rfc4578
 $INCLUDE dictionary.rfc4776
diff --git a/share/dictionary/dhcpv4/dictionary.rfc2131 b/share/dictionary/dhcpv4/dictionary.rfc2131
index 450bdfd1991..670fdf860cd 100644
--- a/share/dictionary/dhcpv4/dictionary.rfc2131
+++ b/share/dictionary/dhcpv4/dictionary.rfc2131
@@ -212,8 +212,7 @@ ATTRIBUTE	Subnet-Selection-Option			118	ipaddr
 ATTRIBUTE	Domain-Search				119	octets # really compressed, concatenated, dns_label array
 # SIP-Servers DHCP Option
 ATTRIBUTE	SIP-Servers-Option			120	octets
-# Classless Static Route Option
-ATTRIBUTE	Classless-Static-Route			121	octets
+
 # CableLabs Client Configuration
 ATTRIBUTE	CCC					122	octets
 # 16 GeoConf Option
diff --git a/share/dictionary/dhcpv4/dictionary.rfc3442 b/share/dictionary/dhcpv4/dictionary.rfc3442
new file mode 100644
index 00000000000..38057a74c5b
--- /dev/null
+++ b/share/dictionary/dhcpv4/dictionary.rfc3442
@@ -0,0 +1,17 @@
+# -*- text -*-
+# Copyright (C) 2022 The FreeRADIUS Server project and contributors
+# This work is licensed under CC-BY version 4.0 https://creativecommons.org/licenses/by/4.0
+# Version $Id$
+##############################################################################
+#
+#  RFC3442 - The Classless Static Route Option for DHCPv4
+#
+#  $Id$
+#
+##############################################################################
+
+ATTRIBUTE	Classless-Static-Route			121	struct
+MEMBER		Destination-Descriptor			struct	array
+MEMBER		Subnet					ipv4prefix prefix=bits
+MEMBER		Router-IP-Address			ipv4addr
+
diff --git a/src/protocols/dhcpv4/decode.c b/src/protocols/dhcpv4/decode.c
index 8721647bb13..f894e882f8b 100644
--- a/src/protocols/dhcpv4/decode.c
+++ b/src/protocols/dhcpv4/decode.c
@@ -211,6 +211,51 @@ static ssize_t decode_value(TALLOC_CTX *ctx, fr_pair_list_t *out, fr_dict_attr_t
 			vp->vp_ipv4addr = htonl(ipaddr & mask);
 			break;
 		}
+
+		if (da_is_bits_prefix(vp->da)) {
+			uint32_t ipaddr, mask;
+
+			if ((data_len == 0) || (*p > 32)) goto raw;
+
+			if (exact && (data_len > 5)) goto raw;
+
+			vp->vp_ip.prefix = *p;
+
+			if (*p > 24) {
+				if (data_len < 5) goto raw;
+				ipaddr = fr_net_to_uint32(p + 1);
+				p += 5;
+
+			} else if (*p > 16) {
+				if (data_len < 4) goto raw;
+				ipaddr = fr_net_to_uint24(p + 1);
+				ipaddr <<= 8;
+				p += 4;
+
+			} else if (*p > 8) {
+				if (data_len < 3) goto raw;
+				ipaddr = fr_net_to_uint16(p + 1);
+				ipaddr <<= 16;
+				p += 3;
+
+			} else if (*p > 0) {
+				if (data_len < 2) goto raw;
+				ipaddr = p[1];
+				ipaddr <<= 24;
+				p += 2;
+
+			} else {
+				p++;
+				ipaddr = 0;
+			}
+
+			mask = ~(uint32_t) 0;
+			mask <<= (32 - vp->vp_ip.prefix);
+
+			vp->vp_ipv4addr = htonl(ipaddr & mask);
+			break;
+		}
+
 		FALL_THROUGH;
 
 	default:
diff --git a/src/protocols/dhcpv4/encode.c b/src/protocols/dhcpv4/encode.c
index 6a88d6d3aa8..aa959eae545 100644
--- a/src/protocols/dhcpv4/encode.c
+++ b/src/protocols/dhcpv4/encode.c
@@ -143,6 +143,21 @@ static ssize_t encode_value(fr_dbuff_t *dbuff,
 			fr_dbuff_in(&work_dbuff, mask);
 			break;
 		}
+
+		if (da_is_bits_prefix(vp->da)) {
+			int num_bytes = (vp->vp_ip.prefix + 0x07) >> 3;
+
+			fr_dbuff_in(&work_dbuff, (uint8_t) vp->vp_ip.prefix);
+
+			if (num_bytes) {
+				FR_DBUFF_IN_MEMCPY_RETURN(&work_dbuff,
+							  (uint8_t const *)&vp->vp_ipv4addr,
+							  num_bytes);
+			}
+
+			break;
+		}
+
 		goto from_network;
 
 	case FR_TYPE_STRING:
diff --git a/src/tests/unit/protocols/dhcpv4/rfc3442.txt b/src/tests/unit/protocols/dhcpv4/rfc3442.txt
new file mode 100644
index 00000000000..b82bb5f415f
--- /dev/null
+++ b/src/tests/unit/protocols/dhcpv4/rfc3442.txt
@@ -0,0 +1,13 @@
+proto dhcpv4
+proto-dictionary dhcpv4
+fuzzer-out dhcpv4
+
+encode-pair Classless-Static-Route = { Destination-Descriptor = { Subnet = 127.0.0.0/8, Router-IP-Address = 127.0.0.1 }, Destination-Descriptor = { Subnet = 192.168.0.0/16, Router-IP-Address = 192.168.0.1 } }
+match 79 0d 08 7f 7f 00 00 01 10 c0 a8 c0 a8 00 01
+
+decode-pair -
+match Classless-Static-Route = { Destination-Descriptor = { Subnet = 127.0.0.0/8, Router-IP-Address = 127.0.0.1 }, Destination-Descriptor = { Subnet = 192.168.0.0/16, Router-IP-Address = 192.168.0.1 } }
+
+
+count
+match 7