ldpd: adapt the code for Quagga

Signed-off-by: Renato Westphal <renato@opensourcerouting.org>

3 files changed, 795 insertions, 1 deletions

diff --git a/doc/Makefile.am b/doc/Makefile.am
index 4a39f0b01..ffb0bf465 100644
--- a/doc/Makefile.am
+++ b/doc/Makefile.am
@@ -87,6 +87,10 @@ if OSPFD
 man_MANS += ospfd.8
 endif
 
+if LDPD
+man_MANS += ldpd.8
+endif
+
 if RIPD
 man_MANS += ripd.8
 endif
@@ -108,7 +112,7 @@ man_MANS += zebra.8
 endif
 
 EXTRA_DIST = BGP-TypeCode draft-zebra-00.ms draft-zebra-00.txt \
-	bgpd.8 isisd.8 ospf6d.8 ospfclient.8 ospfd.8 ripd.8 \
+	bgpd.8 isisd.8 ospf6d.8 ospfclient.8 ospfd.8 ldpd.8 ripd.8 \
 	ripngd.8 pimd.8 vtysh.1 watchquagga.8 zebra.8 quagga.1 \
 	mpls/ChangeLog.opaque.txt mpls/cli_summary.txt \
 	mpls/opaque_lsa.txt mpls/ospfd.conf \
diff --git a/doc/ldpd-basic-test-setup.md b/doc/ldpd-basic-test-setup.md
new file mode 100644
index 000000000..e5e987f9e
--- /dev/null
+++ b/doc/ldpd-basic-test-setup.md
@@ -0,0 +1,681 @@
+## Topology
+
+The goal of this test is to verify that the all the basic functionality
+of ldpd is working as expected, be it running on Linux or OpenBSD. In
+addition to that, more advanced features are also tested, like LDP
+sessions over IPv6, MD5 authentication and pseudowire signaling.
+
+In the topology below there are 3 PE routers, 3 CE routers and one P
+router (not attached to any consumer site).
+
+All routers have IPv4 addresses and OSPF is used as the IGP. The
+three routers from the bottom of the picture, P, PE2 and PE3, are also
+configured for IPv6 (dual-stack) and static IPv6 routes are used to
+provide connectivity among them.
+
+The three CEs share the same VPLS membership. LDP is used to set up the
+LSPs among the PEs and to signal the pseudowires. MD5 authentication is
+used to protect all LDP sessions.
+
+```
+                          CE1 172.16.1.1/24
+                           +
+                           |
+                       +---+---+
+                       |  PE1  |
+                       | IOS XE|
+                       |       |
+                       +---+---+
+                           |
+                           | 10.0.1.0/24
+                           |
+                       +---+---+
+                       |   P   |
+                +------+ IOS XR+------+
+                |      |       |      |
+                |      +-------+      |
+    10.0.2.0/24 |                     | 10.0.3.0/24
+2001:db8:2::/64 |                     | 2001:db8:3::/64
+                |                     |
+            +---+---+             +---+---+
+            |  PE2  |             |  PE3  |
+            |OpenBSD+-------------+ Linux |
+            |       |             |       |
+            +---+---+ 10.0.4.0/24 +---+---+
+                |   2001:db8:4::/64   |
+                +                     +
+ 172.16.1.2/24 CE2                   CE3 172.16.1.3/24
+```
+
+## Configuration
+
+#### Linux
+1 - Enable IPv4/v6 forwarding:
+```
+# sysctl -w net.ipv4.ip_forward=1
+# sysctl -w net.ipv6.conf.all.forwarding=1
+```
+
+2 - Enable MPLS forwarding:
+```
+# modprobe mpls-router
+# modprobe mpls-iptunnel
+# echo 100000 > /proc/sys/net/mpls/platform_labels
+# echo 1 > /proc/sys/net/mpls/conf/eth1/input
+# echo 1 > /proc/sys/net/mpls/conf/eth2/input
+```
+
+3 - Set up the interfaces:
+```
+# ip link add name lo1 type dummy
+# ip link set dev lo1 up
+# ip addr add 4.4.4.4/32 dev lo1
+# ip -6 addr add 4:4:4::4/128 dev lo1
+# ip link set dev eth1 up
+# ip addr add 10.0.4.4/24 dev eth1
+# ip -6 addr add 2001:db8:4::4/64 dev eth1
+# ip link set dev eth2 up
+# ip addr add 10.0.3.4/24 dev eth2
+# ip -6 addr add 2001:db8:3::4/64 dev eth2
+```
+
+4 - Set up the bridge and pseudowire interfaces:
+```
+# ip link add type bridge
+# ip link set dev bridge0 up
+# ip link set dev eth0 up
+# ip link set dev eth0 master bridge0
+# ip link add name mpw0 type dummy
+# ip link set dev mpw0 up
+# ip link set dev mpw0 master bridge0
+# ip link add name mpw1 type dummy
+# ip link set dev mpw1 up
+# ip link set dev mpw1 master bridge0
+```
+
+> NOTE: MPLS support in the Linux kernel is very recent and it still
+doesn't support pseudowire interfaces. We are using here dummy interfaces
+just to show how the VPLS configuration should look like in the future.
+
+5 - Add static IPv6 routes for the remote loopbacks:
+```
+# ip -6 route add 2:2:2::2/128 via 2001:db8:3::2
+# ip -6 route add 3:3:3::3/128 via 2001:db8:4::3
+```
+
+6 - Edit /etc/quagga/ospfd.conf:
+```
+router ospf
+ network 4.4.4.4/32 area 0.0.0.0
+ network 10.0.3.4/24 area 0.0.0.0
+ network 10.0.4.4/24 area 0.0.0.0
+!
+```
+
+7 - Edit /etc/quagga/ldpd.conf:
+```
+debug mpls ldp messages recv
+debug mpls ldp messages sent
+debug mpls ldp zebra
+!
+mpls ldp
+ router-id 4.4.4.4
+ dual-stack cisco-interop
+ neighbor 1.1.1.1 password opensourcerouting
+ neighbor 2.2.2.2 password opensourcerouting
+ neighbor 3.3.3.3 password opensourcerouting
+ !
+ address-family ipv4
+  discovery transport-address 4.4.4.4
+  label local advertise explicit-null
+  !
+  interface eth2
+  !
+  interface eth1
+  !
+ !
+ address-family ipv6
+  discovery transport-address 4:4:4::4
+  ttl-security disable
+  !
+  interface eth2
+  !
+  interface eth1
+  !
+ !
+!
+l2vpn ENG type vpls
+ bridge br0
+ member interface eth0
+ !
+ member pseudowire mpw0
+  neighbor lsr-id 1.1.1.1
+  pw-id 100
+ !
+ member pseudowire mpw1
+  neighbor lsr-id 3.3.3.3
+  neighbor address 3:3:3::3
+  pw-id 100
+ !
+!
+```
+
+> NOTE: We have to disable ttl-security under the ipv6 address-family
+in order to interoperate with the IOS-XR router. GTSM is mandatory for
+LDPv6 but the IOS-XR implementation is not RFC compliant in this regard.
+
+8 - Run zebra, ospfd and ldpd.
+
+#### OpenBSD
+1 - Enable IPv4/v6 forwarding:
+```
+# sysctl net.inet.ip.forwarding=1
+# sysctl net.inet6.ip6.forwarding=1
+```
+
+2 - Enable MPLS forwarding:
+```
+# ifconfig em2 10.0.2.3/24 mpls
+# ifconfig em3 10.0.4.3/24 mpls
+```
+
+3 - Set up the interfaces:
+```
+# ifconfig lo1 alias 3.3.3.3 netmask 255.255.255.255
+# ifconfig lo1 inet6 3:3:3::3/128
+# ifconfig em2 inet6 2001:db8:2::3/64
+# ifconfig em3 inet6 2001:db8:4::3/64
+```
+
+4 - Set up the bridge and pseudowire interfaces:
+```
+# ifconfig bridge0 create
+# ifconfig bridge0 up
+# ifconfig em1 up
+# ifconfig bridge0 add em1
+# ifconfig mpw0 create
+# ifconfig mpw0 up
+# ifconfig bridge0 add mpw0
+# ifconfig mpw1 create
+# ifconfig mpw1 up
+# ifconfig bridge0 add mpw1
+```
+
+5 - Add static IPv6 routes for the remote loopbacks:
+```
+# route -n add 4:4:4::4/128 2001:db8:4::4
+# route -n add 2:2:2::2/128 2001:db8:2::2
+```
+
+6 - Edit /etc/quagga/ospfd.conf:
+```
+router ospf
+ network 10.0.2.3/24 area 0
+ network 10.0.4.3/24 area 0
+ network 3.3.3.3/32 area 0
+!
+```
+
+7 - Edit /etc/quagga/ldpd.conf:
+```
+debug mpls ldp messages recv
+debug mpls ldp messages sent
+debug mpls ldp zebra
+!
+mpls ldp
+ router-id 3.3.3.3
+ dual-stack cisco-interop
+ neighbor 1.1.1.1 password opensourcerouting
+ neighbor 2.2.2.2 password opensourcerouting
+ neighbor 4.4.4.4 password opensourcerouting
+ !
+ address-family ipv4
+  discovery transport-address 3.3.3.3
+  label local advertise explicit-null
+  !
+  interface em3
+  !
+  interface em2
+  !
+ !
+ address-family ipv6
+  discovery transport-address 3:3:3::3
+  ttl-security disable
+  !
+  interface em3
+  !
+  interface em2
+  !
+ !
+!
+l2vpn ENG type vpls
+ bridge br0
+ member interface em1
+ !
+ member pseudowire mpw0
+  neighbor lsr-id 1.1.1.1
+  pw-id 100
+ !
+ member pseudowire mpw1
+  neighbor lsr-id 4.4.4.4
+  neighbor address 4:4:4::4
+  pw-id 100
+ !
+!
+```
+
+8 - Run zebra, ospfd and ldpd.
+
+#### Cisco routers
+CE1 (IOS):
+```
+interface FastEthernet0/0
+ ip address 172.16.1.1 255.255.255.0
+ !
+!
+```
+
+CE2 (IOS):
+```
+interface FastEthernet0/0
+ ip address 172.16.1.2 255.255.255.0
+ !
+!
+```
+
+CE3 (IOS):
+```
+interface FastEthernet0/0
+ ip address 172.16.1.3 255.255.255.0
+ !
+!
+```
+
+PE1 - IOS-XE (1):
+```
+mpls ldp neighbor 2.2.2.2 password opensourcerouting
+mpls ldp neighbor 3.3.3.3 password opensourcerouting
+mpls ldp neighbor 4.4.4.4 password opensourcerouting
+!
+l2vpn vfi context VFI
+ vpn id 1
+ member pseudowire2
+ member pseudowire1
+!
+bridge-domain 1
+ member GigabitEthernet1 service-instance 1
+ member vfi VFI
+!
+interface Loopback1
+ ip address 1.1.1.1 255.255.255.255
+!
+interface pseudowire1
+ encapsulation mpls
+ neighbor 3.3.3.3 100
+!
+interface pseudowire2
+ encapsulation mpls
+ neighbor 4.4.4.4 100
+!
+interface GigabitEthernet3
+ ip address 10.0.1.1 255.255.255.0
+ mpls ip
+!
+router ospf 1
+ network 0.0.0.0 255.255.255.255 area 0
+!
+```
+
+P - IOS-XR (2):
+```
+interface Loopback1
+ ipv4 address 2.2.2.2 255.255.255.255
+ ipv6 address 2:2:2::2/128
+!
+interface GigabitEthernet0/0/0/0
+ ipv4 address 10.0.1.2 255.255.255.0
+!
+interface GigabitEthernet0/0/0/1
+ ipv4 address 10.0.2.2 255.255.255.0
+ ipv6 address 2001:db8:2::2/64
+ ipv6 enable
+!
+interface GigabitEthernet0/0/0/2
+ ipv4 address 10.0.3.2 255.255.255.0
+ ipv6 address 2001:db8:3::2/64
+ ipv6 enable
+!
+router static
+ address-family ipv6 unicast
+  3:3:3::3/128 2001:db8:2::3
+  4:4:4::4/128 2001:db8:3::4
+ !
+!
+router ospf 1
+ router-id 2.2.2.2
+ address-family ipv4 unicast
+ area 0
+  interface Loopback1
+  !
+  interface GigabitEthernet0/0/0/0
+  !
+  interface GigabitEthernet0/0/0/1
+  !
+  interface GigabitEthernet0/0/0/2
+  !
+ !
+!
+mpls ldp
+ router-id 2.2.2.2
+ neighbor
+  1.1.1.1:0 password clear opensourcerouting
+  3.3.3.3:0 password clear opensourcerouting
+  4.4.4.4:0 password clear opensourcerouting
+ !
+ address-family ipv4
+ !
+ address-family ipv6
+  discovery transport-address 2:2:2::2
+ !
+ interface GigabitEthernet0/0/0/0
+  address-family ipv4
+  !
+ !
+ interface GigabitEthernet0/0/0/1
+  address-family ipv4
+  !
+  address-family ipv6
+  !
+ !
+ interface GigabitEthernet0/0/0/2
+  address-family ipv4
+  !
+  address-family ipv6
+  !
+ !
+!
+```
+
+## Verification - Control Plane
+
+Using the CLI on the Linux box, the goal is to ensure that everything
+is working as expected.
+
+First, verify that all the required adjacencies and neighborships sessions
+were established:
+
+```
+linux# show mpls ldp discovery
+Local LDP Identifier: 4.4.4.4:0
+Discovery Sources:
+  Interfaces:
+    eth1: xmit/recv
+      LDP Id: 3.3.3.3:0, Transport address: 3.3.3.3
+          Hold time: 15 sec
+      LDP Id: 3.3.3.3:0, Transport address: 3:3:3::3
+          Hold time: 15 sec
+    eth2: xmit/recv
+      LDP Id: 2.2.2.2:0, Transport address: 2.2.2.2
+          Hold time: 15 sec
+      LDP Id: 2.2.2.2:0, Transport address: 2:2:2::2
+          Hold time: 15 sec
+  Targeted Hellos:
+    4.4.4.4 -> 1.1.1.1: xmit/recv
+      LDP Id: 1.1.1.1:0, Transport address: 1.1.1.1
+          Hold time: 45 sec
+    4:4:4::4 -> 3:3:3::3: xmit/recv
+      LDP Id: 3.3.3.3:0, Transport address: 3:3:3::3
+          Hold time: 45 sec
+
+linux# show mpls ldp neighbor
+Peer LDP Identifier: 1.1.1.1:0
+  TCP connection: 4.4.4.4:40921 - 1.1.1.1:646
+  Session Holdtime: 180 sec
+  State: OPERATIONAL; Downstream-Unsolicited
+  Up time: 00:06:02
+  LDP Discovery Sources:
+    IPv4:
+      Targeted Hello: 1.1.1.1
+
+Peer LDP Identifier: 2.2.2.2:0
+  TCP connection: 4:4:4::4:52286 - 2:2:2::2:646
+  Session Holdtime: 180 sec
+  State: OPERATIONAL; Downstream-Unsolicited
+  Up time: 00:06:02
+  LDP Discovery Sources:
+    IPv4:
+      Interface: eth2
+    IPv6:
+      Interface: eth2
+
+Peer LDP Identifier: 3.3.3.3:0
+  TCP connection: 4:4:4::4:60575 - 3:3:3::3:646
+  Session Holdtime: 180 sec
+  State: OPERATIONAL; Downstream-Unsolicited
+  Up time: 00:05:57
+  LDP Discovery Sources:
+    IPv4:
+      Interface: eth1
+    IPv6:
+      Targeted Hello: 3:3:3::3
+      Interface: eth1
+```
+
+Note that the neighborships with the P and PE2 routers were established
+over IPv6, since this is the default behavior for dual-stack LSRs, as
+specified in RFC 7552. If desired, the **dual-stack transport-connection
+prefer ipv4** command can be used to establish these sessions over IPv4
+(the command should be applied an all routers).
+
+Now, verify that there's a remote label for each PE address:
+```
+linux# show mpls ldp binding
+1.1.1.1/32
+        Local binding: label: 20
+        Remote bindings:
+            Peer                Label
+            -----------------   ---------
+            1.1.1.1             imp-null
+            2.2.2.2             24000
+            3.3.3.3             20
+2.2.2.2/32
+        Local binding: label: 21
+        Remote bindings:
+            Peer                Label
+            -----------------   ---------
+            1.1.1.1             18
+            2.2.2.2             imp-null
+            3.3.3.3             21
+3.3.3.3/32
+        Local binding: label: 22
+        Remote bindings:
+            Peer                Label
+            -----------------   ---------
+            1.1.1.1             21
+            2.2.2.2             24003
+            3.3.3.3             imp-null
+4.4.4.4/32
+        Local binding: label: imp-null
+        Remote bindings:
+            Peer                Label
+            -----------------   ---------
+            1.1.1.1             22
+            2.2.2.2             24001
+            3.3.3.3             22
+10.0.1.0/24
+        Local binding: label: 23
+        Remote bindings:
+            Peer                Label
+            -----------------   ---------
+            1.1.1.1             imp-null
+            2.2.2.2             imp-null
+            3.3.3.3             23
+10.0.2.0/24
+        Local binding: label: 24
+        Remote bindings:
+            Peer                Label
+            -----------------   ---------
+            1.1.1.1             20
+            2.2.2.2             imp-null
+            3.3.3.3             imp-null
+10.0.3.0/24
+        Local binding: label: imp-null
+        Remote bindings:
+            Peer                Label
+            -----------------   ---------
+            1.1.1.1             19
+            2.2.2.2             imp-null
+            3.3.3.3             24
+10.0.4.0/24
+        Local binding: label: imp-null
+        Remote bindings:
+            Peer                Label
+            -----------------   ---------
+            1.1.1.1             23
+            2.2.2.2             24002
+            3.3.3.3             imp-null
+2:2:2::2/128
+        Local binding: label: 18
+        Remote bindings:
+            Peer                Label
+            -----------------   ---------
+            2.2.2.2             imp-null
+            3.3.3.3             18
+3:3:3::3/128
+        Local binding: label: 19
+        Remote bindings:
+            Peer                Label
+            -----------------   ---------
+            2.2.2.2             24007
+4:4:4::4/128
+        Local binding: label: imp-null
+        Remote bindings:
+            Peer                Label
+            -----------------   ---------
+            2.2.2.2             24006
+            3.3.3.3             19
+2001:db8:2::/64
+        Local binding: label: -
+        Remote bindings:
+            Peer                Label
+            -----------------   ---------
+            2.2.2.2             imp-null
+            3.3.3.3             imp-null
+2001:db8:3::/64
+        Local binding: label: imp-null
+        Remote bindings:
+            Peer                Label
+            -----------------   ---------
+            2.2.2.2             imp-null
+2001:db8:4::/64
+        Local binding: label: imp-null
+        Remote bindings:
+            Peer                Label
+            -----------------   ---------
+            3.3.3.3             imp-null
+```
+
+Check if the pseudowires are up:
+```
+linux# show l2vpn atom vc
+Interface Peer ID         VC ID      Name             Status
+--------- --------------- ---------- ---------------- ----------
+mpw1      3.3.3.3         100        ENG              UP
+mpw0      1.1.1.1         100        ENG              UP
+```
+
+Check the label bindings of the pseudowires:
+```
+linux# show l2vpn atom binding
+  Destination Address: 1.1.1.1, VC ID: 100
+    Local Label:  25
+        Cbit: 1,    VC Type: Ethernet,    GroupID: 0
+        MTU: 1500
+    Remote Label:  16
+        Cbit: 1,    VC Type: Ethernet,    GroupID: 0
+        MTU: 1500
+  Destination Address: 3.3.3.3, VC ID: 100
+    Local Label:  26
+        Cbit: 1,    VC Type: Ethernet,    GroupID: 0
+        MTU: 1500
+    Remote Label:  26
+        Cbit: 1,    VC Type: Ethernet,    GroupID: 0
+        MTU: 1500
+```
+
+## Verification - Data Plane
+
+Verify that all the exchanged label mappings were installed in zebra:
+```
+linux# show mpls table
+ Inbound                            Outbound
+   Label     Type          Nexthop     Label
+--------  -------  ---------------  --------
+      17      LDP    2001:db8:3::2         3
+      19      LDP    2001:db8:3::2     24005
+      20      LDP         10.0.3.2     24000
+      21      LDP         10.0.3.2         3
+      22      LDP         10.0.3.2     24001
+      23      LDP         10.0.3.2         3
+      24      LDP         10.0.3.2         3
+      25      LDP         10.0.3.2         3
+
+linux# show ip route ldp
+Codes: K - kernel route, C - connected, S - static, R - RIP,
+       O - OSPF, I - IS-IS, B - BGP, P - PIM, A - Babel, L - LDP,
+       > - selected route, * - FIB route
+
+L>* 1.1.1.1/32 [0/0] via 10.0.3.2, eth2 label 24000
+L>* 3.3.3.3/32 [0/0] via 10.0.3.2, eth2 label 24001
+```
+
+Verify that all the exchanged label mappings were installed in the kernel:
+```
+$ ip -M ro
+17 via inet6 2001:db8:3::2 dev eth2  proto zebra
+19 as to 24005 via inet6 2001:db8:3::2 dev eth2  proto zebra
+20 as to 24000 via inet 10.0.3.2 dev eth2  proto zebra
+21 via inet 10.0.3.2 dev eth2  proto zebra
+22 as to 24001 via inet 10.0.3.2 dev eth2  proto zebra
+23 via inet 10.0.3.2 dev eth2  proto zebra
+24 via inet 10.0.3.2 dev eth2  proto zebra
+25 via inet 10.0.3.2 dev eth2  proto zebra
+$
+$ ip route | grep mpls
+1.1.1.1  encap mpls  24000 via 10.0.3.2 dev eth2  proto zebra  metric 20
+3.3.3.3  encap mpls  24001 via 10.0.3.2 dev eth2  proto zebra  metric 20
+```
+
+Now ping PE1's loopback using lo1's address as a source address:
+```
+$ ping -c 5 -I 4.4.4.4 1.1.1.1
+PING 1.1.1.1 (1.1.1.1) from 4.4.4.4 : 56(84) bytes of data.
+64 bytes from 1.1.1.1: icmp_seq=1 ttl=253 time=3.02 ms
+64 bytes from 1.1.1.1: icmp_seq=2 ttl=253 time=3.13 ms
+64 bytes from 1.1.1.1: icmp_seq=3 ttl=253 time=3.19 ms
+64 bytes from 1.1.1.1: icmp_seq=4 ttl=253 time=3.07 ms
+64 bytes from 1.1.1.1: icmp_seq=5 ttl=253 time=3.27 ms
+
+--- 1.1.1.1 ping statistics ---
+5 packets transmitted, 5 received, 0% packet loss, time 4005ms
+rtt min/avg/max/mdev = 3.022/3.140/3.278/0.096 ms
+```
+
+Verify that the ICMP echo request packets are leaving with the MPLS
+label advertised by the P router. Also, verify that the ICMP echo reply
+packets are arriving with an explicit-null MPLS label:
+```
+# tcpdump -n -i eth2 mpls and icmp
+tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
+listening on eth2, link-type EN10MB (Ethernet), capture size 262144 bytes
+10:01:40.758771 MPLS (label 24000, exp 0, [S], ttl 64) IP 4.4.4.4 > 1.1.1.1: ICMP echo request, id 13370, seq 1, length 64
+10:01:40.761777 MPLS (label 0, exp 0, [S], ttl 254) IP 1.1.1.1 > 4.4.4.4: ICMP echo reply, id 13370, seq 1, length 64
+10:01:41.760343 MPLS (label 24000, exp 0, [S], ttl 64) IP 4.4.4.4 > 1.1.1.1: ICMP echo request, id 13370, seq 2, length 64
+10:01:41.763448 MPLS (label 0, exp 0, [S], ttl 254) IP 1.1.1.1 > 4.4.4.4: ICMP echo reply, id 13370, seq 2, length 64
+10:01:42.761758 MPLS (label 24000, exp 0, [S], ttl 64) IP 4.4.4.4 > 1.1.1.1: ICMP echo request, id 13370, seq 3, length 64
+10:01:42.764924 MPLS (label 0, exp 0, [S], ttl 254) IP 1.1.1.1 > 4.4.4.4: ICMP echo reply, id 13370, seq 3, length 64
+10:01:43.763193 MPLS (label 24000, exp 0, [S], ttl 64) IP 4.4.4.4 > 1.1.1.1: ICMP echo request, id 13370, seq 4, length 64
+10:01:43.766237 MPLS (label 0, exp 0, [S], ttl 254) IP 1.1.1.1 > 4.4.4.4: ICMP echo reply, id 13370, seq 4, length 64
+10:01:44.764552 MPLS (label 24000, exp 0, [S], ttl 64) IP 4.4.4.4 > 1.1.1.1: ICMP echo request, id 13370, seq 5, length 64
+10:01:44.767803 MPLS (label 0, exp 0, [S], ttl 254) IP 1.1.1.1 > 4.4.4.4: ICMP echo reply, id 13370, seq 5, length 64
+```
diff --git a/doc/ldpd.8 b/doc/ldpd.8
new file mode 100644
index 000000000..092ff39d4
--- /dev/null
+++ b/doc/ldpd.8
@@ -0,0 +1,109 @@
+.TH LDPD 8 "29 March 2016" "Quagga LDP daemon" "Version 1.0.20160309"
+.SH NAME
+ldpd \- an LDP engine for use with Quagga routing software.
+.SH SYNOPSIS
+.B ldpd
+[
+.B \-dhv
+] [
+.B \-f
+.I config-file
+] [
+.B \-i
+.I pid-file
+] [
+.B \-P
+.I port-number
+] [
+.B \-A
+.I vty-address
+] [
+.B \-u
+.I user
+] [
+.B \-g
+.I group
+]
+.SH DESCRIPTION
+.B ldpd
+is a component that works with the
+.B Quagga
+routing engine.
+.SH OPTIONS
+Options available for the
+.B ldpd
+command:
+.TP
+\fB\-d\fR, \fB\-\-daemon\fR
+Runs in daemon mode, forking and exiting from tty.
+.TP
+\fB\-f\fR, \fB\-\-config-file \fR\fIconfig-file\fR 
+Specifies the config file to use for startup. If not specified this
+option will likely default to \fB\fI/usr/local/etc/ldpd.conf\fR.
+.TP
+\fB\-g\fR, \fB\-\-group \fR\fIgroup\fR
+Specify the group to run as. Default is \fIquagga\fR.
+.TP
+\fB\-h\fR, \fB\-\-help\fR
+A brief message.
+.TP
+\fB\-i\fR, \fB\-\-pid_file \fR\fIpid-file\fR
+When ldpd starts its process identifier is written to
+\fB\fIpid-file\fR.  The init system uses the recorded PID to stop or
+restart ldpd.  The likely default is \fB\fI/var/run/ldpd.pid\fR.
+.TP
+\fB\-P\fR, \fB\-\-vty_port \fR\fIport-number\fR 
+Specify the port that the ldpd VTY will listen on. This defaults to
+2612, as specified in \fB\fI/etc/services\fR.
+.TP
+\fB\-A\fR, \fB\-\-vty_addr \fR\fIvty-address\fR
+Specify the address that the ldpd VTY will listen on. Default is all
+interfaces.
+.TP
+\fB\-u\fR, \fB\-\-user \fR\fIuser\fR
+Specify the user to run as. Default is \fIquagga\fR.
+.TP
+\fB\-v\fR, \fB\-\-version\fR
+Print the version and exit.
+.SH FILES
+.TP
+.BI /usr/local/sbin/ldpd
+The default location of the 
+.B ldpd
+binary.
+.TP
+.BI /usr/local/etc/ldpd.conf
+The default location of the 
+.B ldpd
+config file.
+.TP
+.BI $(PWD)/ldpd.log 
+If the 
+.B ldpd
+process is config'd to output logs to a file, then you will find this
+file in the directory where you started \fBldpd\fR.
+.SH WARNING
+This man page is intended to be a quick reference for command line
+options. The definitive document is the Info file \fBQuagga\fR.
+.SH DIAGNOSTICS
+The ldpd process may log to standard output, to a VTY, to a log
+file, or through syslog to the system logs. \fBldpd\fR supports many
+debugging options, see the Info file, or the source for details.
+.SH "SEE ALSO"
+.BR bgpd (8),
+.BR ripd (8),
+.BR ripngd (8),
+.BR ospfd (8),
+.BR ospf6d (8),
+.BR isisd (8),
+.BR zebra (8),
+.BR vtysh (1)
+.SH BUGS
+.B ldpd
+eats bugs for breakfast. If you have food for the maintainers try
+.BI http://bugzilla.quagga.net
+.SH AUTHORS
+See
+.BI http://www.quagga.net
+or the Info file for an accurate list of authors.
+