1 files changed, 332 insertions, 0 deletions
diff --git a/freebsd/sys/netinet/cc/cc.c b/freebsd/sys/netinet/cc/cc.c
new file mode 100644
index 00000000..a5a971e6
--- /dev/null
+++ b/freebsd/sys/netinet/cc/cc.c
@@ -0,0 +1,332 @@
+#include <machine/rtems-bsd-config.h>
+
+/*-
+ * Copyright (c) 2007-2008
+ *	Swinburne University of Technology, Melbourne, Australia.
+ * Copyright (c) 2009-2010 Lawrence Stewart <lstewart@freebsd.org>
+ * Copyright (c) 2010 The FreeBSD Foundation
+ * All rights reserved.
+ *
+ * This software was developed at the Centre for Advanced Internet
+ * Architectures, Swinburne University of Technology, by Lawrence Stewart and
+ * James Healy, made possible in part by a grant from the Cisco University
+ * Research Program Fund at Community Foundation Silicon Valley.
+ *
+ * Portions of this software were developed at the Centre for Advanced
+ * Internet Architectures, Swinburne University of Technology, Melbourne,
+ * Australia by David Hayes under sponsorship from the FreeBSD Foundation.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * This software was first released in 2007 by James Healy and Lawrence Stewart
+ * whilst working on the NewTCP research project at Swinburne University of
+ * Technology's Centre for Advanced Internet Architectures, Melbourne,
+ * Australia, which was made possible in part by a grant from the Cisco
+ * University Research Program Fund at Community Foundation Silicon Valley.
+ * More details are available at:
+ *   http://caia.swin.edu.au/urp/newtcp/
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <rtems/bsd/sys/param.h>
+#include <sys/kernel.h>
+#include <sys/libkern.h>
+#include <rtems/bsd/sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/module.h>
+#include <sys/mutex.h>
+#include <sys/queue.h>
+#include <sys/rwlock.h>
+#include <sys/sbuf.h>
+#include <sys/socket.h>
+#include <sys/socketvar.h>
+#include <sys/sysctl.h>
+
+#include <net/if.h>
+#include <net/if_var.h>
+
+#include <netinet/cc.h>
+#include <netinet/in.h>
+#include <netinet/in_pcb.h>
+#include <netinet/tcp_var.h>
+
+#include <netinet/cc/cc_module.h>
+
+/*
+ * List of available cc algorithms on the current system. First element
+ * is used as the system default CC algorithm.
+ */
+struct cc_head cc_list = STAILQ_HEAD_INITIALIZER(cc_list);
+
+/* Protects the cc_list TAILQ. */
+struct rwlock cc_list_lock;
+
+VNET_DEFINE(struct cc_algo *, default_cc_ptr) = &newreno_cc_algo;
+
+/*
+ * Sysctl handler to show and change the default CC algorithm.
+ */
+static int
+cc_default_algo(SYSCTL_HANDLER_ARGS)
+{
+	char default_cc[TCP_CA_NAME_MAX];
+	struct cc_algo *funcs;
+	int err, found;
+
+	err = found = 0;
+
+	if (req->newptr == NULL) {
+		/* Just print the current default. */
+		CC_LIST_RLOCK();
+		strlcpy(default_cc, CC_DEFAULT()->name, TCP_CA_NAME_MAX);
+		CC_LIST_RUNLOCK();
+		err = sysctl_handle_string(oidp, default_cc, 1, req);
+	} else {
+		/* Find algo with specified name and set it to default. */
+		CC_LIST_RLOCK();
+		STAILQ_FOREACH(funcs, &cc_list, entries) {
+			if (strncmp((char *)req->newptr, funcs->name,
+			    TCP_CA_NAME_MAX) == 0) {
+				found = 1;
+				V_default_cc_ptr = funcs;
+			}
+		}
+		CC_LIST_RUNLOCK();
+
+		if (!found)
+			err = ESRCH;
+	}
+
+	return (err);
+}
+
+#ifndef __rtems__
+/*
+ * Sysctl handler to display the list of available CC algorithms.
+ */
+static int
+cc_list_available(SYSCTL_HANDLER_ARGS)
+{
+	struct cc_algo *algo;
+	struct sbuf *s;
+	int err, first, nalgos;
+
+	err = nalgos = 0;
+	first = 1;
+
+	CC_LIST_RLOCK();
+	STAILQ_FOREACH(algo, &cc_list, entries) {
+		nalgos++;
+	}
+	CC_LIST_RUNLOCK();
+
+	s = sbuf_new(NULL, NULL, nalgos * TCP_CA_NAME_MAX, SBUF_FIXEDLEN);
+
+	if (s == NULL)
+		return (ENOMEM);
+
+	/*
+	 * It is theoretically possible for the CC list to have grown in size
+	 * since the call to sbuf_new() and therefore for the sbuf to be too
+	 * small. If this were to happen (incredibly unlikely), the sbuf will
+	 * reach an overflow condition, sbuf_printf() will return an error and
+	 * the sysctl will fail gracefully.
+	 */
+	CC_LIST_RLOCK();
+	STAILQ_FOREACH(algo, &cc_list, entries) {
+		err = sbuf_printf(s, first ? "%s" : ", %s", algo->name);
+		if (err) {
+			/* Sbuf overflow condition. */
+			err = EOVERFLOW;
+			break;
+		}
+		first = 0;
+	}
+	CC_LIST_RUNLOCK();
+
+	if (!err) {
+		sbuf_finish(s);
+		err = sysctl_handle_string(oidp, sbuf_data(s), 1, req);
+	}
+
+	sbuf_delete(s);
+	return (err);
+}
+#endif /* __rtems__ */
+
+/*
+ * Reset the default CC algo to NewReno for any netstack which is using the algo
+ * that is about to go away as its default.
+ */
+static void
+cc_checkreset_default(struct cc_algo *remove_cc)
+{
+	VNET_ITERATOR_DECL(vnet_iter);
+
+	CC_LIST_LOCK_ASSERT();
+
+	VNET_LIST_RLOCK_NOSLEEP();
+	VNET_FOREACH(vnet_iter) {
+		CURVNET_SET(vnet_iter);
+		if (strncmp(CC_DEFAULT()->name, remove_cc->name,
+		    TCP_CA_NAME_MAX) == 0)
+			V_default_cc_ptr = &newreno_cc_algo;
+		CURVNET_RESTORE();
+	}
+	VNET_LIST_RUNLOCK_NOSLEEP();
+}
+
+/*
+ * Initialise CC subsystem on system boot.
+ */
+static void
+cc_init(void)
+{
+	CC_LIST_LOCK_INIT();
+	STAILQ_INIT(&cc_list);
+}
+
+/*
+ * Returns non-zero on success, 0 on failure.
+ */
+int
+cc_deregister_algo(struct cc_algo *remove_cc)
+{
+	struct cc_algo *funcs, *tmpfuncs;
+	int err;
+
+	err = ENOENT;
+
+	/* Never allow newreno to be deregistered. */
+	if (&newreno_cc_algo == remove_cc)
+		return (EPERM);
+
+	/* Remove algo from cc_list so that new connections can't use it. */
+	CC_LIST_WLOCK();
+	STAILQ_FOREACH_SAFE(funcs, &cc_list, entries, tmpfuncs) {
+		if (funcs == remove_cc) {
+			cc_checkreset_default(remove_cc);
+			STAILQ_REMOVE(&cc_list, funcs, cc_algo, entries);
+			err = 0;
+			break;
+		}
+	}
+	CC_LIST_WUNLOCK();
+
+	if (!err)
+		/*
+		 * XXXLAS:
+		 * - We may need to handle non-zero return values in future.
+		 * - If we add CC framework support for protocols other than
+		 *   TCP, we may want a more generic way to handle this step.
+		 */
+		tcp_ccalgounload(remove_cc);
+
+	return (err);
+}
+
+/*
+ * Returns 0 on success, non-zero on failure.
+ */
+int
+cc_register_algo(struct cc_algo *add_cc)
+{
+	struct cc_algo *funcs;
+	int err;
+
+	err = 0;
+
+	/*
+	 * Iterate over list of registered CC algorithms and make sure
+	 * we're not trying to add a duplicate.
+	 */
+	CC_LIST_WLOCK();
+	STAILQ_FOREACH(funcs, &cc_list, entries) {
+		if (funcs == add_cc || strncmp(funcs->name, add_cc->name,
+		    TCP_CA_NAME_MAX) == 0)
+			err = EEXIST;
+	}
+
+	if (!err)
+		STAILQ_INSERT_TAIL(&cc_list, add_cc, entries);
+
+	CC_LIST_WUNLOCK();
+
+	return (err);
+}
+
+/*
+ * Handles kld related events. Returns 0 on success, non-zero on failure.
+ */
+int
+cc_modevent(module_t mod, int event_type, void *data)
+{
+	struct cc_algo *algo;
+	int err;
+
+	err = 0;
+	algo = (struct cc_algo *)data;
+
+	switch(event_type) {
+	case MOD_LOAD:
+		if (algo->mod_init != NULL)
+			err = algo->mod_init();
+		if (!err)
+			err = cc_register_algo(algo);
+		break;
+
+	case MOD_QUIESCE:
+	case MOD_SHUTDOWN:
+	case MOD_UNLOAD:
+		err = cc_deregister_algo(algo);
+		if (!err && algo->mod_destroy != NULL)
+			algo->mod_destroy();
+		if (err == ENOENT)
+			err = 0;
+		break;
+
+	default:
+		err = EINVAL;
+		break;
+	}
+
+	return (err);
+}
+
+SYSINIT(cc, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_FIRST, cc_init, NULL);
+
+/* Declare sysctl tree and populate it. */
+SYSCTL_NODE(_net_inet_tcp, OID_AUTO, cc, CTLFLAG_RW, NULL,
+    "congestion control related settings");
+
+SYSCTL_VNET_PROC(_net_inet_tcp_cc, OID_AUTO, algorithm, CTLTYPE_STRING|CTLFLAG_RW,
+    NULL, 0, cc_default_algo, "A", "default congestion control algorithm");
+
+#ifndef __rtems__
+SYSCTL_PROC(_net_inet_tcp_cc, OID_AUTO, available, CTLTYPE_STRING|CTLFLAG_RD,
+    NULL, 0, cc_list_available, "A",
+    "list available congestion control algorithms");
+#endif /* __rtems__ */