Merge pull request #551 from jkroonza/dhcpv6relay

dhcpv6relay plugin from Jaco Kroon

Author: paulusmack

configure.ac

@@ -330,6 +330,7 @@ AC_CONFIG_FILES([
     pppd/plugins/pppoatm/Makefile
     pppd/plugins/pppol2tp/Makefile
     pppd/plugins/radius/Makefile
+    pppd/plugins/dhcpv6relay/Makefile
     pppdump/Makefile
     pppstats/Makefile
     scripts/Makefile

pppd/Makefile.am

@@ -82,6 +82,7 @@ pppd_SOURCES = \
     lcp.c \
     magic.c \
     main.c \
+    event-handler.c \
     options.c \
     session.c \
     tty.c \

pppd/event-handler.c

@@ -0,0 +1,130 @@
+/*
+ * event-handler.c - generic select() based event handler.  Should be system
+ * independent.
+ *
+ * Copyright (c) 1994-2025 Paul Mackerras. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
+ * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
+ * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
+ * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * Derived from sys-linux.c and sys-solaris.c by Jaco Kroon <jaco@uls.co.za>.
+ */
+#include <limits.h>
+#include <stddef.h>
+#include <errno.h>
+#include <sys/select.h>
+
+#include "pppd.h"
+#include "pppd-private.h"
+
+struct event_handler {
+    struct event_handler* next;
+    int fd;
+    event_cb cb;
+    void* ctx;
+};
+
+static fd_set in_fds;		/* set of fds that wait_input waits for */
+static int max_in_fd;		/* highest fd set in in_fds */
+static struct event_handler* handlers;
+static int called_remove;
+
+/********************************************************************
+ *
+ * wait_input - wait until there is data available,
+ * for the length of time specified by *timo (indefinite
+ * if timo is NULL).
+ */
+
+void wait_input(struct timeval *timo)
+{
+    fd_set ready, exc;
+    int n;
+    struct event_handler* h = handlers, *nh;
+
+    called_remove = 0;
+    ready = in_fds;
+    exc = in_fds;
+    n = select(max_in_fd + 1, &ready, NULL, &exc, timo);
+    if (n < 0 && errno != EINTR)
+	fatal("select: %m");
+
+    while (h) {
+	nh = h->next;
+	if (FD_ISSET(h->fd, &ready)) {
+	    FD_CLR(h->fd, &ready); /* clear so that if we need to re-iterate we won't call again */
+	    h->cb(h->fd, h->ctx);
+
+	    if (called_remove) {
+		nh = handlers;
+		called_remove = 0;
+	    }
+	}
+	h = nh;
+    }
+}
+
+/*
+ * add_fd - add an fd to the set that wait_input waits for.
+ */
+void add_fd(int fd)
+{
+    if (fd >= FD_SETSIZE)
+	fatal("internal error: file descriptor too large (%d)", fd);
+    FD_SET(fd, &in_fds);
+    if (fd > max_in_fd)
+	max_in_fd = fd;
+}
+
+void add_fd_callback(int fd, event_cb cb, void* ctx)
+{
+    struct event_handler *n = malloc(sizeof(*n));
+    n->next = handlers;
+    n->fd = fd;
+    n->cb = cb;
+    n->ctx = ctx;
+    handlers = n;
+    add_fd(fd);
+}
+
+/*
+ * remove_fd - remove an fd from the set that wait_input waits for.
+ */
+void remove_fd(int fd)
+{
+    struct event_handler** h, *t;
+    FD_CLR(fd, &in_fds);
+
+    for (h = &handlers; *h; h = &(*h)->next) {
+	if (fd == (*h)->fd) {
+	    called_remove = 1;
+	    t = (*h)->next;
+	    free(*h);
+	    *h = t;
+	    return;
+	}
+    }
+}
+
+void event_handler_init()
+{
+    FD_ZERO(&in_fds);
+    max_in_fd = 0;
+}

pppd/main.c

@@ -497,6 +497,8 @@ main(int argc, char *argv[])
 	fd_devnull = i;
     }
 
+    event_handler_init();
+
     /*
      * Initialize system-dependent stuff.
      */

pppd/plugins/Makefile.am

@@ -17,5 +17,5 @@ winbind_la_LDFLAGS = $(PLUGIN_LDFLAGS)
 winbind_la_SOURCES = winbind.c
 
 if !SUNOS
-SUBDIRS = pppoe pppoatm pppol2tp radius
+SUBDIRS = pppoe pppoatm pppol2tp radius dhcpv6relay
 endif

pppd/plugins/dhcpv6relay/Makefile.am

@@ -0,0 +1,8 @@
+pppd_plugin_LTLIBRARIES = dhcpv6relay.la
+pppd_plugindir = $(PPPD_PLUGIN_DIR)
+
+noinst_HEADERS = dhcpv6relay.h
+
+dhcpv6relay_la_CPPFLAGS = -I${top_srcdir} -DSYSCONFDIR=\"${sysconfdir}\" -DPLUGIN
+dhcpv6relay_la_LDFLAGS = -module -avoid-version
+dhcpv6relay_la_SOURCES = dhcpv6relay.c