lib: Replace shim IPCPs with points of attachment

Removes the UDP and Ethernet shim IPCPs. The unicast and broadcast
IPCPs can now directly attach to a "legacy" socket. We adopt Saltzer's
Point-of-Attachment terminology, also advocated in Day's "Patterns in
Network Architecture". The "poa" component manages these
PoA's with one management thread, one link monitoring thread and one
thread per attached point.

For Ethernet PoA's the irm connect and enroll can resolve the
destination IPCP or Layer name with a broadcast name query over the
attached PoAs (first reply wins). UDP PoA's require a destination IP
address or FQDN.

attach to a local endpoint (required both server and client side):

 irm ipcp poa attach name a udp 10.0.0.1
 irm ipcp poa attach name a udp 10.0.0.1:3435
 irm ipcp poa attach name a udp [::1]:3435
 irm ipcp poa attach name a eth dev eth0
 irm ipcp poa attach name a eth dev eth0 ethertype 0xA000

release a PoA (refused while it carries a flow):

 irm ipcp poa detach name a udp 10.0.0.1:3435
 irm ipcp poa detach name a eth eth0

list an IPCP's PoAs:

 irm ipcp poa list name a

connect to a peer, by name or at an address:

 irm ipcp connect name b dst a
 irm ipcp connect name b dst a eth
 irm ipcp connect name b dst a eth dev eth0
 irm ipcp connect name b dst a udp 10.0.0.1:3435
 irm ipcp connect name b dst a udp peer.example.com:3435

disconnect by peer name, no address:

 irm ipcp disconnect name b dst a
 irm ipcp disconnect name b dst a component mgmt

enroll has the same shape as connect:

 irm ipcp enroll name b layer lr autobind
 irm ipcp enroll name b layer lr autobind eth dev eth0
 irm ipcp enroll name b layer lr autobind udp 10.0.0.1:3435

the IRMd config file attaches PoAs and names peers the same way:

 udp = [ "10.0.0.1", "10.0.0.1:3436" ]
 eth = [ "eth0", {dev="eth1", ethertype=0xA007} ]

 enrol={dst="LAN", eth={dev="eth0"}}
 conn=[{dst="lan3", eth={}}, {dst="lan4", udp="10.0.0.1:3435"}]

Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>

1 files changed, 0 insertions, 42 deletions

diff --git a/src/ipcpd/udp/udp4.c b/src/ipcpd/udp/udp4.c
deleted file mode 100644
index ff57bc09..00000000
--- a/src/ipcpd/udp/udp4.c
+++ /dev/null
@@ -1,42 +0,0 @@
-/*
- * Ouroboros - Copyright (C) 2016 - 2026
- *
- * IPC process over UDP/IPv4
- *
- *    Dimitri Staessens <dimitri@ouroboros.rocks>
- *    Sander Vrijders   <sander@ouroboros.rocks>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., http://www.fsf.org/about/contact/.
- */
-
-#if defined(__linux__) || defined(__CYGWIN__)
-#define _DEFAULT_SOURCE
-#else
-#define _POSIX_C_SOURCE 200112L
-#endif
-
-#include <ouroboros/ipcp-dev.h>
-
-#define BUILD_IPCP_UDP4
-#define THIS_TYPE                IPCP_UDP4
-#define TYPE_STR                 "IPCP over UDP/IPv4"
-#define OUROBOROS_PREFIX         "ipcpd/udp4"
-#define IPCP_UDP_MAX_PACKET_SIZE 8980
-#define __AF                     AF_INET
-#define __ADDRSTRLEN             INET_ADDRSTRLEN
-#define __SOCKADDR               sockaddr_in
-#define __ADDR                   in_addr
-#define __ADDR_ANY_INIT          { .s_addr = INADDR_ANY }
-
-#include "udp.c"