The 0b70e3e78b
changed the original design of a single entry point
into pfil(9) chains providing separate functions for the filtering
points that always provide mbufs and know the direction of a flow.
The motivation was to reduce branching. The logical continuation
would be to do the same for the filtering points that always provide
a memory pointer and retire the single entry point.
o Hooks now provide two functions: one for mbufs and optional for
memory pointers.
o pfil_hook_args() has a new member and pfil_add_hook() has a
requirement to zero out uninitialized data. Bump PFIL_VERSION.
o As it was before, a hook function for a memory pointer may realloc
into an mbuf. Such mbuf would be returned via a pointer that must
be provided in argument.
o The only hook that supports memory pointers is ipfw:default-link.
It is rewritten to provide two functions.
o All remaining uses of pfil_run_hooks() are converted to
pfil_mem_in().
o Transparent union of pfil_packet_t and tricks to fix pointer
alignment are retired. Internal pfil_realloc() reduces down to
m_devget() and thus is retired, too.
Reviewed by: mjg, ocochard
Differential revision: https://reviews.freebsd.org/D37977
1596 lines
45 KiB
C
1596 lines
45 KiB
C
/*-
|
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* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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|
*
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* Copyright (c) 2007-2009
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* Swinburne University of Technology, Melbourne, Australia.
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* Copyright (c) 2009-2010, The FreeBSD Foundation
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* All rights reserved.
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*
|
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* Portions of this software were developed at the Centre for Advanced
|
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* Internet Architectures, Swinburne University of Technology, Melbourne,
|
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* Australia by Lawrence Stewart under sponsorship from the FreeBSD Foundation.
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*
|
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* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
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* are met:
|
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* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
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* 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.
|
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*
|
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* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
|
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
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* SUCH DAMAGE.
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*/
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/******************************************************
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* Statistical Information For TCP Research (SIFTR)
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*
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* A FreeBSD kernel module that adds very basic intrumentation to the
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* TCP stack, allowing internal stats to be recorded to a log file
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* for experimental, debugging and performance analysis purposes.
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*
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* SIFTR was first released in 2007 by James Healy and Lawrence Stewart whilst
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* working on the NewTCP research project at Swinburne University of
|
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* Technology's Centre for Advanced Internet Architectures, Melbourne,
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* Australia, which was made possible in part by a grant from the Cisco
|
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* University Research Program Fund at Community Foundation Silicon Valley.
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* More details are available at:
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* http://caia.swin.edu.au/urp/newtcp/
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*
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* Work on SIFTR v1.2.x was sponsored by the FreeBSD Foundation as part of
|
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* the "Enhancing the FreeBSD TCP Implementation" project 2008-2009.
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* More details are available at:
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* http://www.freebsdfoundation.org/
|
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* http://caia.swin.edu.au/freebsd/etcp09/
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*
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* Lawrence Stewart is the current maintainer, and all contact regarding
|
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* SIFTR should be directed to him via email: lastewart@swin.edu.au
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*
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* Initial release date: June 2007
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* Most recent update: September 2010
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******************************************************/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include <sys/param.h>
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#include <sys/alq.h>
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#include <sys/errno.h>
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#include <sys/eventhandler.h>
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#include <sys/hash.h>
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|
#include <sys/kernel.h>
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#include <sys/kthread.h>
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|
#include <sys/lock.h>
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|
#include <sys/mbuf.h>
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#include <sys/module.h>
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#include <sys/mutex.h>
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|
#include <sys/pcpu.h>
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#include <sys/proc.h>
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|
#include <sys/sbuf.h>
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|
#include <sys/sdt.h>
|
|
#include <sys/smp.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/socketvar.h>
|
|
#include <sys/sysctl.h>
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#include <sys/unistd.h>
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|
|
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#include <net/if.h>
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#include <net/if_var.h>
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|
#include <net/pfil.h>
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|
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#include <netinet/in.h>
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#include <netinet/in_kdtrace.h>
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|
#include <netinet/in_pcb.h>
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|
#include <netinet/in_systm.h>
|
|
#include <netinet/in_var.h>
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#include <netinet/ip.h>
|
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#include <netinet/ip_var.h>
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#include <netinet/tcp_var.h>
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|
|
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#ifdef SIFTR_IPV6
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#include <netinet/ip6.h>
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#include <netinet6/ip6_var.h>
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#include <netinet6/in6_pcb.h>
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#endif /* SIFTR_IPV6 */
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|
|
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#include <machine/in_cksum.h>
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|
|
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/*
|
|
* Three digit version number refers to X.Y.Z where:
|
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* X is the major version number
|
|
* Y is bumped to mark backwards incompatible changes
|
|
* Z is bumped to mark backwards compatible changes
|
|
*/
|
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#define V_MAJOR 1
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#define V_BACKBREAK 2
|
|
#define V_BACKCOMPAT 4
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#define MODVERSION __CONCAT(V_MAJOR, __CONCAT(V_BACKBREAK, V_BACKCOMPAT))
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|
#define MODVERSION_STR __XSTRING(V_MAJOR) "." __XSTRING(V_BACKBREAK) "." \
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__XSTRING(V_BACKCOMPAT)
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|
|
|
#define HOOK 0
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#define UNHOOK 1
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|
#define SIFTR_EXPECTED_MAX_TCP_FLOWS 65536
|
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#define SYS_NAME "FreeBSD"
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#define PACKET_TAG_SIFTR 100
|
|
#define PACKET_COOKIE_SIFTR 21749576
|
|
#define SIFTR_LOG_FILE_MODE 0644
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#define SIFTR_DISABLE 0
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#define SIFTR_ENABLE 1
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|
|
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/*
|
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* Hard upper limit on the length of log messages. Bump this up if you add new
|
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* data fields such that the line length could exceed the below value.
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*/
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#define MAX_LOG_MSG_LEN 300
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/* XXX: Make this a sysctl tunable. */
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#define SIFTR_ALQ_BUFLEN (1000*MAX_LOG_MSG_LEN)
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|
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/*
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* 1 byte for IP version
|
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* IPv4: src/dst IP (4+4) + src/dst port (2+2) = 12 bytes
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* IPv6: src/dst IP (16+16) + src/dst port (2+2) = 36 bytes
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*/
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#ifdef SIFTR_IPV6
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#define FLOW_KEY_LEN 37
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#else
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#define FLOW_KEY_LEN 13
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#endif
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#ifdef SIFTR_IPV6
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#define SIFTR_IPMODE 6
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#else
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#define SIFTR_IPMODE 4
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#endif
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|
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/* useful macros */
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|
#define UPPER_SHORT(X) (((X) & 0xFFFF0000) >> 16)
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#define LOWER_SHORT(X) ((X) & 0x0000FFFF)
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#define FIRST_OCTET(X) (((X) & 0xFF000000) >> 24)
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#define SECOND_OCTET(X) (((X) & 0x00FF0000) >> 16)
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#define THIRD_OCTET(X) (((X) & 0x0000FF00) >> 8)
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#define FOURTH_OCTET(X) ((X) & 0x000000FF)
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static MALLOC_DEFINE(M_SIFTR, "siftr", "dynamic memory used by SIFTR");
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static MALLOC_DEFINE(M_SIFTR_PKTNODE, "siftr_pktnode",
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"SIFTR pkt_node struct");
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static MALLOC_DEFINE(M_SIFTR_HASHNODE, "siftr_hashnode",
|
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"SIFTR flow_hash_node struct");
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|
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/* Used as links in the pkt manager queue. */
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struct pkt_node {
|
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/* Timestamp of pkt as noted in the pfil hook. */
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struct timeval tval;
|
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/* Direction pkt is travelling. */
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enum {
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DIR_IN = 0,
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DIR_OUT = 1,
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} direction;
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/* IP version pkt_node relates to; either INP_IPV4 or INP_IPV6. */
|
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uint8_t ipver;
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/* Hash of the pkt which triggered the log message. */
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|
uint32_t hash;
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|
/* Local/foreign IP address. */
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#ifdef SIFTR_IPV6
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uint32_t ip_laddr[4];
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uint32_t ip_faddr[4];
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#else
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uint8_t ip_laddr[4];
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uint8_t ip_faddr[4];
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#endif
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/* Local TCP port. */
|
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uint16_t tcp_localport;
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|
/* Foreign TCP port. */
|
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uint16_t tcp_foreignport;
|
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/* Congestion Window (bytes). */
|
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uint32_t snd_cwnd;
|
|
/* Sending Window (bytes). */
|
|
uint32_t snd_wnd;
|
|
/* Receive Window (bytes). */
|
|
uint32_t rcv_wnd;
|
|
/* More tcpcb flags storage */
|
|
uint32_t t_flags2;
|
|
/* Slow Start Threshold (bytes). */
|
|
uint32_t snd_ssthresh;
|
|
/* Current state of the TCP FSM. */
|
|
int conn_state;
|
|
/* Max Segment Size (bytes). */
|
|
u_int max_seg_size;
|
|
/*
|
|
* Smoothed RTT stored as found in the TCP control block
|
|
* in units of (TCP_RTT_SCALE*hz).
|
|
*/
|
|
int smoothed_rtt;
|
|
/* Is SACK enabled? */
|
|
u_char sack_enabled;
|
|
/* Window scaling for snd window. */
|
|
u_char snd_scale;
|
|
/* Window scaling for recv window. */
|
|
u_char rcv_scale;
|
|
/* TCP control block flags. */
|
|
u_int flags;
|
|
/* Retransmit timeout length. */
|
|
int rxt_length;
|
|
/* Size of the TCP send buffer in bytes. */
|
|
u_int snd_buf_hiwater;
|
|
/* Current num bytes in the send socket buffer. */
|
|
u_int snd_buf_cc;
|
|
/* Size of the TCP receive buffer in bytes. */
|
|
u_int rcv_buf_hiwater;
|
|
/* Current num bytes in the receive socket buffer. */
|
|
u_int rcv_buf_cc;
|
|
/* Number of bytes inflight that we are waiting on ACKs for. */
|
|
u_int sent_inflight_bytes;
|
|
/* Number of segments currently in the reassembly queue. */
|
|
int t_segqlen;
|
|
/* Flowid for the connection. */
|
|
u_int flowid;
|
|
/* Flow type for the connection. */
|
|
u_int flowtype;
|
|
/* Link to next pkt_node in the list. */
|
|
STAILQ_ENTRY(pkt_node) nodes;
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|
};
|
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|
|
struct flow_hash_node
|
|
{
|
|
uint16_t counter;
|
|
uint8_t key[FLOW_KEY_LEN];
|
|
LIST_ENTRY(flow_hash_node) nodes;
|
|
};
|
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|
|
struct siftr_stats
|
|
{
|
|
/* # TCP pkts seen by the SIFTR PFIL hooks, including any skipped. */
|
|
uint64_t n_in;
|
|
uint64_t n_out;
|
|
/* # pkts skipped due to failed malloc calls. */
|
|
uint32_t nskip_in_malloc;
|
|
uint32_t nskip_out_malloc;
|
|
/* # pkts skipped due to failed mtx acquisition. */
|
|
uint32_t nskip_in_mtx;
|
|
uint32_t nskip_out_mtx;
|
|
/* # pkts skipped due to failed inpcb lookups. */
|
|
uint32_t nskip_in_inpcb;
|
|
uint32_t nskip_out_inpcb;
|
|
/* # pkts skipped due to failed tcpcb lookups. */
|
|
uint32_t nskip_in_tcpcb;
|
|
uint32_t nskip_out_tcpcb;
|
|
/* # pkts skipped due to stack reinjection. */
|
|
uint32_t nskip_in_dejavu;
|
|
uint32_t nskip_out_dejavu;
|
|
};
|
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|
|
DPCPU_DEFINE_STATIC(struct siftr_stats, ss);
|
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|
|
static volatile unsigned int siftr_exit_pkt_manager_thread = 0;
|
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static unsigned int siftr_enabled = 0;
|
|
static unsigned int siftr_pkts_per_log = 1;
|
|
static unsigned int siftr_generate_hashes = 0;
|
|
static uint16_t siftr_port_filter = 0;
|
|
/* static unsigned int siftr_binary_log = 0; */
|
|
static char siftr_logfile[PATH_MAX] = "/var/log/siftr.log";
|
|
static char siftr_logfile_shadow[PATH_MAX] = "/var/log/siftr.log";
|
|
static u_long siftr_hashmask;
|
|
STAILQ_HEAD(pkthead, pkt_node) pkt_queue = STAILQ_HEAD_INITIALIZER(pkt_queue);
|
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LIST_HEAD(listhead, flow_hash_node) *counter_hash;
|
|
static int wait_for_pkt;
|
|
static struct alq *siftr_alq = NULL;
|
|
static struct mtx siftr_pkt_queue_mtx;
|
|
static struct mtx siftr_pkt_mgr_mtx;
|
|
static struct thread *siftr_pkt_manager_thr = NULL;
|
|
static char direction[2] = {'i','o'};
|
|
|
|
/* Required function prototypes. */
|
|
static int siftr_sysctl_enabled_handler(SYSCTL_HANDLER_ARGS);
|
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static int siftr_sysctl_logfile_name_handler(SYSCTL_HANDLER_ARGS);
|
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|
|
/* Declare the net.inet.siftr sysctl tree and populate it. */
|
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|
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SYSCTL_DECL(_net_inet_siftr);
|
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|
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SYSCTL_NODE(_net_inet, OID_AUTO, siftr, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
|
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"siftr related settings");
|
|
|
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SYSCTL_PROC(_net_inet_siftr, OID_AUTO, enabled,
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CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
|
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&siftr_enabled, 0, &siftr_sysctl_enabled_handler, "IU",
|
|
"switch siftr module operations on/off");
|
|
|
|
SYSCTL_PROC(_net_inet_siftr, OID_AUTO, logfile,
|
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CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &siftr_logfile_shadow,
|
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sizeof(siftr_logfile_shadow), &siftr_sysctl_logfile_name_handler, "A",
|
|
"file to save siftr log messages to");
|
|
|
|
SYSCTL_UINT(_net_inet_siftr, OID_AUTO, ppl, CTLFLAG_RW,
|
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&siftr_pkts_per_log, 1,
|
|
"number of packets between generating a log message");
|
|
|
|
SYSCTL_UINT(_net_inet_siftr, OID_AUTO, genhashes, CTLFLAG_RW,
|
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&siftr_generate_hashes, 0,
|
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"enable packet hash generation");
|
|
|
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SYSCTL_U16(_net_inet_siftr, OID_AUTO, port_filter, CTLFLAG_RW,
|
|
&siftr_port_filter, 0,
|
|
"enable packet filter on a TCP port");
|
|
|
|
/* XXX: TODO
|
|
SYSCTL_UINT(_net_inet_siftr, OID_AUTO, binary, CTLFLAG_RW,
|
|
&siftr_binary_log, 0,
|
|
"write log files in binary instead of ascii");
|
|
*/
|
|
|
|
/* Begin functions. */
|
|
|
|
static void
|
|
siftr_process_pkt(struct pkt_node * pkt_node)
|
|
{
|
|
struct flow_hash_node *hash_node;
|
|
struct listhead *counter_list;
|
|
struct siftr_stats *ss;
|
|
struct ale *log_buf;
|
|
uint8_t key[FLOW_KEY_LEN];
|
|
uint8_t found_match, key_offset;
|
|
|
|
hash_node = NULL;
|
|
ss = DPCPU_PTR(ss);
|
|
found_match = 0;
|
|
key_offset = 1;
|
|
|
|
/*
|
|
* Create the key that will be used to create a hash index
|
|
* into our hash table. Our key consists of:
|
|
* ipversion, localip, localport, foreignip, foreignport
|
|
*/
|
|
key[0] = pkt_node->ipver;
|
|
memcpy(key + key_offset, &pkt_node->ip_laddr,
|
|
sizeof(pkt_node->ip_laddr));
|
|
key_offset += sizeof(pkt_node->ip_laddr);
|
|
memcpy(key + key_offset, &pkt_node->tcp_localport,
|
|
sizeof(pkt_node->tcp_localport));
|
|
key_offset += sizeof(pkt_node->tcp_localport);
|
|
memcpy(key + key_offset, &pkt_node->ip_faddr,
|
|
sizeof(pkt_node->ip_faddr));
|
|
key_offset += sizeof(pkt_node->ip_faddr);
|
|
memcpy(key + key_offset, &pkt_node->tcp_foreignport,
|
|
sizeof(pkt_node->tcp_foreignport));
|
|
|
|
counter_list = counter_hash +
|
|
(hash32_buf(key, sizeof(key), 0) & siftr_hashmask);
|
|
|
|
/*
|
|
* If the list is not empty i.e. the hash index has
|
|
* been used by another flow previously.
|
|
*/
|
|
if (LIST_FIRST(counter_list) != NULL) {
|
|
/*
|
|
* Loop through the hash nodes in the list.
|
|
* There should normally only be 1 hash node in the list,
|
|
* except if there have been collisions at the hash index
|
|
* computed by hash32_buf().
|
|
*/
|
|
LIST_FOREACH(hash_node, counter_list, nodes) {
|
|
/*
|
|
* Check if the key for the pkt we are currently
|
|
* processing is the same as the key stored in the
|
|
* hash node we are currently processing.
|
|
* If they are the same, then we've found the
|
|
* hash node that stores the counter for the flow
|
|
* the pkt belongs to.
|
|
*/
|
|
if (memcmp(hash_node->key, key, sizeof(key)) == 0) {
|
|
found_match = 1;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* If this flow hash hasn't been seen before or we have a collision. */
|
|
if (hash_node == NULL || !found_match) {
|
|
/* Create a new hash node to store the flow's counter. */
|
|
hash_node = malloc(sizeof(struct flow_hash_node),
|
|
M_SIFTR_HASHNODE, M_WAITOK);
|
|
|
|
if (hash_node != NULL) {
|
|
/* Initialise our new hash node list entry. */
|
|
hash_node->counter = 0;
|
|
memcpy(hash_node->key, key, sizeof(key));
|
|
LIST_INSERT_HEAD(counter_list, hash_node, nodes);
|
|
} else {
|
|
/* Malloc failed. */
|
|
if (pkt_node->direction == DIR_IN)
|
|
ss->nskip_in_malloc++;
|
|
else
|
|
ss->nskip_out_malloc++;
|
|
|
|
return;
|
|
}
|
|
} else if (siftr_pkts_per_log > 1) {
|
|
/*
|
|
* Taking the remainder of the counter divided
|
|
* by the current value of siftr_pkts_per_log
|
|
* and storing that in counter provides a neat
|
|
* way to modulate the frequency of log
|
|
* messages being written to the log file.
|
|
*/
|
|
hash_node->counter = (hash_node->counter + 1) %
|
|
siftr_pkts_per_log;
|
|
|
|
/*
|
|
* If we have not seen enough packets since the last time
|
|
* we wrote a log message for this connection, return.
|
|
*/
|
|
if (hash_node->counter > 0)
|
|
return;
|
|
}
|
|
|
|
log_buf = alq_getn(siftr_alq, MAX_LOG_MSG_LEN, ALQ_WAITOK);
|
|
|
|
if (log_buf == NULL)
|
|
return; /* Should only happen if the ALQ is shutting down. */
|
|
|
|
#ifdef SIFTR_IPV6
|
|
pkt_node->ip_laddr[3] = ntohl(pkt_node->ip_laddr[3]);
|
|
pkt_node->ip_faddr[3] = ntohl(pkt_node->ip_faddr[3]);
|
|
|
|
if (pkt_node->ipver == INP_IPV6) { /* IPv6 packet */
|
|
pkt_node->ip_laddr[0] = ntohl(pkt_node->ip_laddr[0]);
|
|
pkt_node->ip_laddr[1] = ntohl(pkt_node->ip_laddr[1]);
|
|
pkt_node->ip_laddr[2] = ntohl(pkt_node->ip_laddr[2]);
|
|
pkt_node->ip_faddr[0] = ntohl(pkt_node->ip_faddr[0]);
|
|
pkt_node->ip_faddr[1] = ntohl(pkt_node->ip_faddr[1]);
|
|
pkt_node->ip_faddr[2] = ntohl(pkt_node->ip_faddr[2]);
|
|
|
|
/* Construct an IPv6 log message. */
|
|
log_buf->ae_bytesused = snprintf(log_buf->ae_data,
|
|
MAX_LOG_MSG_LEN,
|
|
"%c,0x%08x,%zd.%06ld,%x:%x:%x:%x:%x:%x:%x:%x,%u,%x:%x:%x:"
|
|
"%x:%x:%x:%x:%x,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,"
|
|
"%u,%d,%u,%u,%u,%u,%u,%u,%u,%u\n",
|
|
direction[pkt_node->direction],
|
|
pkt_node->hash,
|
|
pkt_node->tval.tv_sec,
|
|
pkt_node->tval.tv_usec,
|
|
UPPER_SHORT(pkt_node->ip_laddr[0]),
|
|
LOWER_SHORT(pkt_node->ip_laddr[0]),
|
|
UPPER_SHORT(pkt_node->ip_laddr[1]),
|
|
LOWER_SHORT(pkt_node->ip_laddr[1]),
|
|
UPPER_SHORT(pkt_node->ip_laddr[2]),
|
|
LOWER_SHORT(pkt_node->ip_laddr[2]),
|
|
UPPER_SHORT(pkt_node->ip_laddr[3]),
|
|
LOWER_SHORT(pkt_node->ip_laddr[3]),
|
|
ntohs(pkt_node->tcp_localport),
|
|
UPPER_SHORT(pkt_node->ip_faddr[0]),
|
|
LOWER_SHORT(pkt_node->ip_faddr[0]),
|
|
UPPER_SHORT(pkt_node->ip_faddr[1]),
|
|
LOWER_SHORT(pkt_node->ip_faddr[1]),
|
|
UPPER_SHORT(pkt_node->ip_faddr[2]),
|
|
LOWER_SHORT(pkt_node->ip_faddr[2]),
|
|
UPPER_SHORT(pkt_node->ip_faddr[3]),
|
|
LOWER_SHORT(pkt_node->ip_faddr[3]),
|
|
ntohs(pkt_node->tcp_foreignport),
|
|
pkt_node->snd_ssthresh,
|
|
pkt_node->snd_cwnd,
|
|
pkt_node->t_flags2,
|
|
pkt_node->snd_wnd,
|
|
pkt_node->rcv_wnd,
|
|
pkt_node->snd_scale,
|
|
pkt_node->rcv_scale,
|
|
pkt_node->conn_state,
|
|
pkt_node->max_seg_size,
|
|
pkt_node->smoothed_rtt,
|
|
pkt_node->sack_enabled,
|
|
pkt_node->flags,
|
|
pkt_node->rxt_length,
|
|
pkt_node->snd_buf_hiwater,
|
|
pkt_node->snd_buf_cc,
|
|
pkt_node->rcv_buf_hiwater,
|
|
pkt_node->rcv_buf_cc,
|
|
pkt_node->sent_inflight_bytes,
|
|
pkt_node->t_segqlen,
|
|
pkt_node->flowid,
|
|
pkt_node->flowtype);
|
|
} else { /* IPv4 packet */
|
|
pkt_node->ip_laddr[0] = FIRST_OCTET(pkt_node->ip_laddr[3]);
|
|
pkt_node->ip_laddr[1] = SECOND_OCTET(pkt_node->ip_laddr[3]);
|
|
pkt_node->ip_laddr[2] = THIRD_OCTET(pkt_node->ip_laddr[3]);
|
|
pkt_node->ip_laddr[3] = FOURTH_OCTET(pkt_node->ip_laddr[3]);
|
|
pkt_node->ip_faddr[0] = FIRST_OCTET(pkt_node->ip_faddr[3]);
|
|
pkt_node->ip_faddr[1] = SECOND_OCTET(pkt_node->ip_faddr[3]);
|
|
pkt_node->ip_faddr[2] = THIRD_OCTET(pkt_node->ip_faddr[3]);
|
|
pkt_node->ip_faddr[3] = FOURTH_OCTET(pkt_node->ip_faddr[3]);
|
|
#endif /* SIFTR_IPV6 */
|
|
|
|
/* Construct an IPv4 log message. */
|
|
log_buf->ae_bytesused = snprintf(log_buf->ae_data,
|
|
MAX_LOG_MSG_LEN,
|
|
"%c,0x%08x,%jd.%06ld,%u.%u.%u.%u,%u,%u.%u.%u.%u,%u,%u,%u,"
|
|
"%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%d,%u,%u,%u,%u,%u,%u,%u,%u\n",
|
|
direction[pkt_node->direction],
|
|
pkt_node->hash,
|
|
(intmax_t)pkt_node->tval.tv_sec,
|
|
pkt_node->tval.tv_usec,
|
|
pkt_node->ip_laddr[0],
|
|
pkt_node->ip_laddr[1],
|
|
pkt_node->ip_laddr[2],
|
|
pkt_node->ip_laddr[3],
|
|
ntohs(pkt_node->tcp_localport),
|
|
pkt_node->ip_faddr[0],
|
|
pkt_node->ip_faddr[1],
|
|
pkt_node->ip_faddr[2],
|
|
pkt_node->ip_faddr[3],
|
|
ntohs(pkt_node->tcp_foreignport),
|
|
pkt_node->snd_ssthresh,
|
|
pkt_node->snd_cwnd,
|
|
pkt_node->t_flags2,
|
|
pkt_node->snd_wnd,
|
|
pkt_node->rcv_wnd,
|
|
pkt_node->snd_scale,
|
|
pkt_node->rcv_scale,
|
|
pkt_node->conn_state,
|
|
pkt_node->max_seg_size,
|
|
pkt_node->smoothed_rtt,
|
|
pkt_node->sack_enabled,
|
|
pkt_node->flags,
|
|
pkt_node->rxt_length,
|
|
pkt_node->snd_buf_hiwater,
|
|
pkt_node->snd_buf_cc,
|
|
pkt_node->rcv_buf_hiwater,
|
|
pkt_node->rcv_buf_cc,
|
|
pkt_node->sent_inflight_bytes,
|
|
pkt_node->t_segqlen,
|
|
pkt_node->flowid,
|
|
pkt_node->flowtype);
|
|
#ifdef SIFTR_IPV6
|
|
}
|
|
#endif
|
|
|
|
alq_post_flags(siftr_alq, log_buf, 0);
|
|
}
|
|
|
|
static void
|
|
siftr_pkt_manager_thread(void *arg)
|
|
{
|
|
STAILQ_HEAD(pkthead, pkt_node) tmp_pkt_queue =
|
|
STAILQ_HEAD_INITIALIZER(tmp_pkt_queue);
|
|
struct pkt_node *pkt_node, *pkt_node_temp;
|
|
uint8_t draining;
|
|
|
|
draining = 2;
|
|
|
|
mtx_lock(&siftr_pkt_mgr_mtx);
|
|
|
|
/* draining == 0 when queue has been flushed and it's safe to exit. */
|
|
while (draining) {
|
|
/*
|
|
* Sleep until we are signalled to wake because thread has
|
|
* been told to exit or until 1 tick has passed.
|
|
*/
|
|
mtx_sleep(&wait_for_pkt, &siftr_pkt_mgr_mtx, PWAIT, "pktwait",
|
|
1);
|
|
|
|
/* Gain exclusive access to the pkt_node queue. */
|
|
mtx_lock(&siftr_pkt_queue_mtx);
|
|
|
|
/*
|
|
* Move pkt_queue to tmp_pkt_queue, which leaves
|
|
* pkt_queue empty and ready to receive more pkt_nodes.
|
|
*/
|
|
STAILQ_CONCAT(&tmp_pkt_queue, &pkt_queue);
|
|
|
|
/*
|
|
* We've finished making changes to the list. Unlock it
|
|
* so the pfil hooks can continue queuing pkt_nodes.
|
|
*/
|
|
mtx_unlock(&siftr_pkt_queue_mtx);
|
|
|
|
/*
|
|
* We can't hold a mutex whilst calling siftr_process_pkt
|
|
* because ALQ might sleep waiting for buffer space.
|
|
*/
|
|
mtx_unlock(&siftr_pkt_mgr_mtx);
|
|
|
|
/* Flush all pkt_nodes to the log file. */
|
|
STAILQ_FOREACH_SAFE(pkt_node, &tmp_pkt_queue, nodes,
|
|
pkt_node_temp) {
|
|
siftr_process_pkt(pkt_node);
|
|
STAILQ_REMOVE_HEAD(&tmp_pkt_queue, nodes);
|
|
free(pkt_node, M_SIFTR_PKTNODE);
|
|
}
|
|
|
|
KASSERT(STAILQ_EMPTY(&tmp_pkt_queue),
|
|
("SIFTR tmp_pkt_queue not empty after flush"));
|
|
|
|
mtx_lock(&siftr_pkt_mgr_mtx);
|
|
|
|
/*
|
|
* If siftr_exit_pkt_manager_thread gets set during the window
|
|
* where we are draining the tmp_pkt_queue above, there might
|
|
* still be pkts in pkt_queue that need to be drained.
|
|
* Allow one further iteration to occur after
|
|
* siftr_exit_pkt_manager_thread has been set to ensure
|
|
* pkt_queue is completely empty before we kill the thread.
|
|
*
|
|
* siftr_exit_pkt_manager_thread is set only after the pfil
|
|
* hooks have been removed, so only 1 extra iteration
|
|
* is needed to drain the queue.
|
|
*/
|
|
if (siftr_exit_pkt_manager_thread)
|
|
draining--;
|
|
}
|
|
|
|
mtx_unlock(&siftr_pkt_mgr_mtx);
|
|
|
|
/* Calls wakeup on this thread's struct thread ptr. */
|
|
kthread_exit();
|
|
}
|
|
|
|
static uint32_t
|
|
hash_pkt(struct mbuf *m, uint32_t offset)
|
|
{
|
|
uint32_t hash;
|
|
|
|
hash = 0;
|
|
|
|
while (m != NULL && offset > m->m_len) {
|
|
/*
|
|
* The IP packet payload does not start in this mbuf, so
|
|
* need to figure out which mbuf it starts in and what offset
|
|
* into the mbuf's data region the payload starts at.
|
|
*/
|
|
offset -= m->m_len;
|
|
m = m->m_next;
|
|
}
|
|
|
|
while (m != NULL) {
|
|
/* Ensure there is data in the mbuf */
|
|
if ((m->m_len - offset) > 0)
|
|
hash = hash32_buf(m->m_data + offset,
|
|
m->m_len - offset, hash);
|
|
|
|
m = m->m_next;
|
|
offset = 0;
|
|
}
|
|
|
|
return (hash);
|
|
}
|
|
|
|
/*
|
|
* Check if a given mbuf has the SIFTR mbuf tag. If it does, log the fact that
|
|
* it's a reinjected packet and return. If it doesn't, tag the mbuf and return.
|
|
* Return value >0 means the caller should skip processing this mbuf.
|
|
*/
|
|
static inline int
|
|
siftr_chkreinject(struct mbuf *m, int dir, struct siftr_stats *ss)
|
|
{
|
|
if (m_tag_locate(m, PACKET_COOKIE_SIFTR, PACKET_TAG_SIFTR, NULL)
|
|
!= NULL) {
|
|
if (dir == PFIL_IN)
|
|
ss->nskip_in_dejavu++;
|
|
else
|
|
ss->nskip_out_dejavu++;
|
|
|
|
return (1);
|
|
} else {
|
|
struct m_tag *tag = m_tag_alloc(PACKET_COOKIE_SIFTR,
|
|
PACKET_TAG_SIFTR, 0, M_NOWAIT);
|
|
if (tag == NULL) {
|
|
if (dir == PFIL_IN)
|
|
ss->nskip_in_malloc++;
|
|
else
|
|
ss->nskip_out_malloc++;
|
|
|
|
return (1);
|
|
}
|
|
|
|
m_tag_prepend(m, tag);
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Look up an inpcb for a packet. Return the inpcb pointer if found, or NULL
|
|
* otherwise.
|
|
*/
|
|
static inline struct inpcb *
|
|
siftr_findinpcb(int ipver, struct ip *ip, struct mbuf *m, uint16_t sport,
|
|
uint16_t dport, int dir, struct siftr_stats *ss)
|
|
{
|
|
struct inpcb *inp;
|
|
|
|
/* We need the tcbinfo lock. */
|
|
INP_INFO_WUNLOCK_ASSERT(&V_tcbinfo);
|
|
|
|
if (dir == PFIL_IN)
|
|
inp = (ipver == INP_IPV4 ?
|
|
in_pcblookup(&V_tcbinfo, ip->ip_src, sport, ip->ip_dst,
|
|
dport, INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif)
|
|
:
|
|
#ifdef SIFTR_IPV6
|
|
in6_pcblookup(&V_tcbinfo,
|
|
&((struct ip6_hdr *)ip)->ip6_src, sport,
|
|
&((struct ip6_hdr *)ip)->ip6_dst, dport, INPLOOKUP_RLOCKPCB,
|
|
m->m_pkthdr.rcvif)
|
|
#else
|
|
NULL
|
|
#endif
|
|
);
|
|
|
|
else
|
|
inp = (ipver == INP_IPV4 ?
|
|
in_pcblookup(&V_tcbinfo, ip->ip_dst, dport, ip->ip_src,
|
|
sport, INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif)
|
|
:
|
|
#ifdef SIFTR_IPV6
|
|
in6_pcblookup(&V_tcbinfo,
|
|
&((struct ip6_hdr *)ip)->ip6_dst, dport,
|
|
&((struct ip6_hdr *)ip)->ip6_src, sport, INPLOOKUP_RLOCKPCB,
|
|
m->m_pkthdr.rcvif)
|
|
#else
|
|
NULL
|
|
#endif
|
|
);
|
|
|
|
/* If we can't find the inpcb, bail. */
|
|
if (inp == NULL) {
|
|
if (dir == PFIL_IN)
|
|
ss->nskip_in_inpcb++;
|
|
else
|
|
ss->nskip_out_inpcb++;
|
|
}
|
|
|
|
return (inp);
|
|
}
|
|
|
|
static inline void
|
|
siftr_siftdata(struct pkt_node *pn, struct inpcb *inp, struct tcpcb *tp,
|
|
int ipver, int dir, int inp_locally_locked)
|
|
{
|
|
#ifdef SIFTR_IPV6
|
|
if (ipver == INP_IPV4) {
|
|
pn->ip_laddr[3] = inp->inp_laddr.s_addr;
|
|
pn->ip_faddr[3] = inp->inp_faddr.s_addr;
|
|
#else
|
|
*((uint32_t *)pn->ip_laddr) = inp->inp_laddr.s_addr;
|
|
*((uint32_t *)pn->ip_faddr) = inp->inp_faddr.s_addr;
|
|
#endif
|
|
#ifdef SIFTR_IPV6
|
|
} else {
|
|
pn->ip_laddr[0] = inp->in6p_laddr.s6_addr32[0];
|
|
pn->ip_laddr[1] = inp->in6p_laddr.s6_addr32[1];
|
|
pn->ip_laddr[2] = inp->in6p_laddr.s6_addr32[2];
|
|
pn->ip_laddr[3] = inp->in6p_laddr.s6_addr32[3];
|
|
pn->ip_faddr[0] = inp->in6p_faddr.s6_addr32[0];
|
|
pn->ip_faddr[1] = inp->in6p_faddr.s6_addr32[1];
|
|
pn->ip_faddr[2] = inp->in6p_faddr.s6_addr32[2];
|
|
pn->ip_faddr[3] = inp->in6p_faddr.s6_addr32[3];
|
|
}
|
|
#endif
|
|
pn->tcp_localport = inp->inp_lport;
|
|
pn->tcp_foreignport = inp->inp_fport;
|
|
pn->snd_cwnd = tp->snd_cwnd;
|
|
pn->snd_wnd = tp->snd_wnd;
|
|
pn->rcv_wnd = tp->rcv_wnd;
|
|
pn->t_flags2 = tp->t_flags2;
|
|
pn->snd_ssthresh = tp->snd_ssthresh;
|
|
pn->snd_scale = tp->snd_scale;
|
|
pn->rcv_scale = tp->rcv_scale;
|
|
pn->conn_state = tp->t_state;
|
|
pn->max_seg_size = tp->t_maxseg;
|
|
pn->smoothed_rtt = tp->t_srtt;
|
|
pn->sack_enabled = (tp->t_flags & TF_SACK_PERMIT) != 0;
|
|
pn->flags = tp->t_flags;
|
|
pn->rxt_length = tp->t_rxtcur;
|
|
pn->snd_buf_hiwater = inp->inp_socket->so_snd.sb_hiwat;
|
|
pn->snd_buf_cc = sbused(&inp->inp_socket->so_snd);
|
|
pn->rcv_buf_hiwater = inp->inp_socket->so_rcv.sb_hiwat;
|
|
pn->rcv_buf_cc = sbused(&inp->inp_socket->so_rcv);
|
|
pn->sent_inflight_bytes = tp->snd_max - tp->snd_una;
|
|
pn->t_segqlen = tp->t_segqlen;
|
|
pn->flowid = inp->inp_flowid;
|
|
pn->flowtype = inp->inp_flowtype;
|
|
|
|
/* We've finished accessing the tcb so release the lock. */
|
|
if (inp_locally_locked)
|
|
INP_RUNLOCK(inp);
|
|
|
|
pn->ipver = ipver;
|
|
pn->direction = (dir == PFIL_IN ? DIR_IN : DIR_OUT);
|
|
|
|
/*
|
|
* Significantly more accurate than using getmicrotime(), but slower!
|
|
* Gives true microsecond resolution at the expense of a hit to
|
|
* maximum pps throughput processing when SIFTR is loaded and enabled.
|
|
*/
|
|
microtime(&pn->tval);
|
|
TCP_PROBE1(siftr, &pn);
|
|
|
|
}
|
|
|
|
/*
|
|
* pfil hook that is called for each IPv4 packet making its way through the
|
|
* stack in either direction.
|
|
* The pfil subsystem holds a non-sleepable mutex somewhere when
|
|
* calling our hook function, so we can't sleep at all.
|
|
* It's very important to use the M_NOWAIT flag with all function calls
|
|
* that support it so that they won't sleep, otherwise you get a panic.
|
|
*/
|
|
static pfil_return_t
|
|
siftr_chkpkt(struct mbuf **m, struct ifnet *ifp, int flags,
|
|
void *ruleset __unused, struct inpcb *inp)
|
|
{
|
|
struct pkt_node *pn;
|
|
struct ip *ip;
|
|
struct tcphdr *th;
|
|
struct tcpcb *tp;
|
|
struct siftr_stats *ss;
|
|
unsigned int ip_hl;
|
|
int inp_locally_locked, dir;
|
|
|
|
inp_locally_locked = 0;
|
|
dir = PFIL_DIR(flags);
|
|
ss = DPCPU_PTR(ss);
|
|
|
|
/*
|
|
* m_pullup is not required here because ip_{input|output}
|
|
* already do the heavy lifting for us.
|
|
*/
|
|
|
|
ip = mtod(*m, struct ip *);
|
|
|
|
/* Only continue processing if the packet is TCP. */
|
|
if (ip->ip_p != IPPROTO_TCP)
|
|
goto ret;
|
|
|
|
/*
|
|
* Create a tcphdr struct starting at the correct offset
|
|
* in the IP packet. ip->ip_hl gives the ip header length
|
|
* in 4-byte words, so multiply it to get the size in bytes.
|
|
*/
|
|
ip_hl = (ip->ip_hl << 2);
|
|
th = (struct tcphdr *)((caddr_t)ip + ip_hl);
|
|
|
|
/*
|
|
* Only pkts selected by the tcp port filter
|
|
* can be inserted into the pkt_queue
|
|
*/
|
|
if ((siftr_port_filter != 0) &&
|
|
(siftr_port_filter != ntohs(th->th_sport)) &&
|
|
(siftr_port_filter != ntohs(th->th_dport))) {
|
|
goto ret;
|
|
}
|
|
|
|
/*
|
|
* If a kernel subsystem reinjects packets into the stack, our pfil
|
|
* hook will be called multiple times for the same packet.
|
|
* Make sure we only process unique packets.
|
|
*/
|
|
if (siftr_chkreinject(*m, dir, ss))
|
|
goto ret;
|
|
|
|
if (dir == PFIL_IN)
|
|
ss->n_in++;
|
|
else
|
|
ss->n_out++;
|
|
|
|
/*
|
|
* If the pfil hooks don't provide a pointer to the
|
|
* inpcb, we need to find it ourselves and lock it.
|
|
*/
|
|
if (!inp) {
|
|
/* Find the corresponding inpcb for this pkt. */
|
|
inp = siftr_findinpcb(INP_IPV4, ip, *m, th->th_sport,
|
|
th->th_dport, dir, ss);
|
|
|
|
if (inp == NULL)
|
|
goto ret;
|
|
else
|
|
inp_locally_locked = 1;
|
|
}
|
|
|
|
INP_LOCK_ASSERT(inp);
|
|
|
|
/* Find the TCP control block that corresponds with this packet */
|
|
tp = intotcpcb(inp);
|
|
|
|
/*
|
|
* If we can't find the TCP control block (happens occasionaly for a
|
|
* packet sent during the shutdown phase of a TCP connection), bail
|
|
*/
|
|
if (tp == NULL) {
|
|
if (dir == PFIL_IN)
|
|
ss->nskip_in_tcpcb++;
|
|
else
|
|
ss->nskip_out_tcpcb++;
|
|
|
|
goto inp_unlock;
|
|
}
|
|
|
|
|
|
pn = malloc(sizeof(struct pkt_node), M_SIFTR_PKTNODE, M_NOWAIT|M_ZERO);
|
|
|
|
if (pn == NULL) {
|
|
if (dir == PFIL_IN)
|
|
ss->nskip_in_malloc++;
|
|
else
|
|
ss->nskip_out_malloc++;
|
|
|
|
goto inp_unlock;
|
|
}
|
|
|
|
siftr_siftdata(pn, inp, tp, INP_IPV4, dir, inp_locally_locked);
|
|
|
|
if (siftr_generate_hashes) {
|
|
if ((*m)->m_pkthdr.csum_flags & CSUM_TCP) {
|
|
/*
|
|
* For outbound packets, the TCP checksum isn't
|
|
* calculated yet. This is a problem for our packet
|
|
* hashing as the receiver will calc a different hash
|
|
* to ours if we don't include the correct TCP checksum
|
|
* in the bytes being hashed. To work around this
|
|
* problem, we manually calc the TCP checksum here in
|
|
* software. We unset the CSUM_TCP flag so the lower
|
|
* layers don't recalc it.
|
|
*/
|
|
(*m)->m_pkthdr.csum_flags &= ~CSUM_TCP;
|
|
|
|
/*
|
|
* Calculate the TCP checksum in software and assign
|
|
* to correct TCP header field, which will follow the
|
|
* packet mbuf down the stack. The trick here is that
|
|
* tcp_output() sets th->th_sum to the checksum of the
|
|
* pseudo header for us already. Because of the nature
|
|
* of the checksumming algorithm, we can sum over the
|
|
* entire IP payload (i.e. TCP header and data), which
|
|
* will include the already calculated pseduo header
|
|
* checksum, thus giving us the complete TCP checksum.
|
|
*
|
|
* To put it in simple terms, if checksum(1,2,3,4)=10,
|
|
* then checksum(1,2,3,4,5) == checksum(10,5).
|
|
* This property is what allows us to "cheat" and
|
|
* checksum only the IP payload which has the TCP
|
|
* th_sum field populated with the pseudo header's
|
|
* checksum, and not need to futz around checksumming
|
|
* pseudo header bytes and TCP header/data in one hit.
|
|
* Refer to RFC 1071 for more info.
|
|
*
|
|
* NB: in_cksum_skip(struct mbuf *m, int len, int skip)
|
|
* in_cksum_skip 2nd argument is NOT the number of
|
|
* bytes to read from the mbuf at "skip" bytes offset
|
|
* from the start of the mbuf (very counter intuitive!).
|
|
* The number of bytes to read is calculated internally
|
|
* by the function as len-skip i.e. to sum over the IP
|
|
* payload (TCP header + data) bytes, it is INCORRECT
|
|
* to call the function like this:
|
|
* in_cksum_skip(at, ip->ip_len - offset, offset)
|
|
* Rather, it should be called like this:
|
|
* in_cksum_skip(at, ip->ip_len, offset)
|
|
* which means read "ip->ip_len - offset" bytes from
|
|
* the mbuf cluster "at" at offset "offset" bytes from
|
|
* the beginning of the "at" mbuf's data pointer.
|
|
*/
|
|
th->th_sum = in_cksum_skip(*m, ntohs(ip->ip_len),
|
|
ip_hl);
|
|
}
|
|
|
|
/*
|
|
* XXX: Having to calculate the checksum in software and then
|
|
* hash over all bytes is really inefficient. Would be nice to
|
|
* find a way to create the hash and checksum in the same pass
|
|
* over the bytes.
|
|
*/
|
|
pn->hash = hash_pkt(*m, ip_hl);
|
|
}
|
|
|
|
mtx_lock(&siftr_pkt_queue_mtx);
|
|
STAILQ_INSERT_TAIL(&pkt_queue, pn, nodes);
|
|
mtx_unlock(&siftr_pkt_queue_mtx);
|
|
goto ret;
|
|
|
|
inp_unlock:
|
|
if (inp_locally_locked)
|
|
INP_RUNLOCK(inp);
|
|
|
|
ret:
|
|
return (PFIL_PASS);
|
|
}
|
|
|
|
#ifdef SIFTR_IPV6
|
|
static pfil_return_t
|
|
siftr_chkpkt6(struct mbuf **m, struct ifnet *ifp, int flags,
|
|
void *ruleset __unused, struct inpcb *inp)
|
|
{
|
|
struct pkt_node *pn;
|
|
struct ip6_hdr *ip6;
|
|
struct tcphdr *th;
|
|
struct tcpcb *tp;
|
|
struct siftr_stats *ss;
|
|
unsigned int ip6_hl;
|
|
int inp_locally_locked, dir;
|
|
|
|
inp_locally_locked = 0;
|
|
dir = PFIL_DIR(flags);
|
|
ss = DPCPU_PTR(ss);
|
|
|
|
/*
|
|
* m_pullup is not required here because ip6_{input|output}
|
|
* already do the heavy lifting for us.
|
|
*/
|
|
|
|
ip6 = mtod(*m, struct ip6_hdr *);
|
|
|
|
/*
|
|
* Only continue processing if the packet is TCP
|
|
* XXX: We should follow the next header fields
|
|
* as shown on Pg 6 RFC 2460, but right now we'll
|
|
* only check pkts that have no extension headers.
|
|
*/
|
|
if (ip6->ip6_nxt != IPPROTO_TCP)
|
|
goto ret6;
|
|
|
|
/*
|
|
* Create a tcphdr struct starting at the correct offset
|
|
* in the ipv6 packet.
|
|
*/
|
|
ip6_hl = sizeof(struct ip6_hdr);
|
|
th = (struct tcphdr *)((caddr_t)ip6 + ip6_hl);
|
|
|
|
/*
|
|
* Only pkts selected by the tcp port filter
|
|
* can be inserted into the pkt_queue
|
|
*/
|
|
if ((siftr_port_filter != 0) &&
|
|
(siftr_port_filter != ntohs(th->th_sport)) &&
|
|
(siftr_port_filter != ntohs(th->th_dport))) {
|
|
goto ret6;
|
|
}
|
|
|
|
/*
|
|
* If a kernel subsystem reinjects packets into the stack, our pfil
|
|
* hook will be called multiple times for the same packet.
|
|
* Make sure we only process unique packets.
|
|
*/
|
|
if (siftr_chkreinject(*m, dir, ss))
|
|
goto ret6;
|
|
|
|
if (dir == PFIL_IN)
|
|
ss->n_in++;
|
|
else
|
|
ss->n_out++;
|
|
|
|
/*
|
|
* For inbound packets, the pfil hooks don't provide a pointer to the
|
|
* inpcb, so we need to find it ourselves and lock it.
|
|
*/
|
|
if (!inp) {
|
|
/* Find the corresponding inpcb for this pkt. */
|
|
inp = siftr_findinpcb(INP_IPV6, (struct ip *)ip6, *m,
|
|
th->th_sport, th->th_dport, dir, ss);
|
|
|
|
if (inp == NULL)
|
|
goto ret6;
|
|
else
|
|
inp_locally_locked = 1;
|
|
}
|
|
|
|
/* Find the TCP control block that corresponds with this packet. */
|
|
tp = intotcpcb(inp);
|
|
|
|
/*
|
|
* If we can't find the TCP control block (happens occasionaly for a
|
|
* packet sent during the shutdown phase of a TCP connection), bail
|
|
*/
|
|
if (tp == NULL) {
|
|
if (dir == PFIL_IN)
|
|
ss->nskip_in_tcpcb++;
|
|
else
|
|
ss->nskip_out_tcpcb++;
|
|
|
|
goto inp_unlock6;
|
|
}
|
|
|
|
|
|
pn = malloc(sizeof(struct pkt_node), M_SIFTR_PKTNODE, M_NOWAIT|M_ZERO);
|
|
|
|
if (pn == NULL) {
|
|
if (dir == PFIL_IN)
|
|
ss->nskip_in_malloc++;
|
|
else
|
|
ss->nskip_out_malloc++;
|
|
|
|
goto inp_unlock6;
|
|
}
|
|
|
|
siftr_siftdata(pn, inp, tp, INP_IPV6, dir, inp_locally_locked);
|
|
|
|
/* XXX: Figure out how to generate hashes for IPv6 packets. */
|
|
|
|
mtx_lock(&siftr_pkt_queue_mtx);
|
|
STAILQ_INSERT_TAIL(&pkt_queue, pn, nodes);
|
|
mtx_unlock(&siftr_pkt_queue_mtx);
|
|
goto ret6;
|
|
|
|
inp_unlock6:
|
|
if (inp_locally_locked)
|
|
INP_RUNLOCK(inp);
|
|
|
|
ret6:
|
|
return (PFIL_PASS);
|
|
}
|
|
#endif /* #ifdef SIFTR_IPV6 */
|
|
|
|
VNET_DEFINE_STATIC(pfil_hook_t, siftr_inet_hook);
|
|
#define V_siftr_inet_hook VNET(siftr_inet_hook)
|
|
#ifdef SIFTR_IPV6
|
|
VNET_DEFINE_STATIC(pfil_hook_t, siftr_inet6_hook);
|
|
#define V_siftr_inet6_hook VNET(siftr_inet6_hook)
|
|
#endif
|
|
static int
|
|
siftr_pfil(int action)
|
|
{
|
|
struct pfil_hook_args pha = {
|
|
.pa_version = PFIL_VERSION,
|
|
.pa_flags = PFIL_IN | PFIL_OUT,
|
|
.pa_modname = "siftr",
|
|
.pa_rulname = "default",
|
|
};
|
|
struct pfil_link_args pla = {
|
|
.pa_version = PFIL_VERSION,
|
|
.pa_flags = PFIL_IN | PFIL_OUT | PFIL_HEADPTR | PFIL_HOOKPTR,
|
|
};
|
|
|
|
VNET_ITERATOR_DECL(vnet_iter);
|
|
|
|
VNET_LIST_RLOCK();
|
|
VNET_FOREACH(vnet_iter) {
|
|
CURVNET_SET(vnet_iter);
|
|
|
|
if (action == HOOK) {
|
|
pha.pa_mbuf_chk = siftr_chkpkt;
|
|
pha.pa_type = PFIL_TYPE_IP4;
|
|
V_siftr_inet_hook = pfil_add_hook(&pha);
|
|
pla.pa_hook = V_siftr_inet_hook;
|
|
pla.pa_head = V_inet_pfil_head;
|
|
(void)pfil_link(&pla);
|
|
#ifdef SIFTR_IPV6
|
|
pha.pa_mbuf_chk = siftr_chkpkt6;
|
|
pha.pa_type = PFIL_TYPE_IP6;
|
|
V_siftr_inet6_hook = pfil_add_hook(&pha);
|
|
pla.pa_hook = V_siftr_inet6_hook;
|
|
pla.pa_head = V_inet6_pfil_head;
|
|
(void)pfil_link(&pla);
|
|
#endif
|
|
} else if (action == UNHOOK) {
|
|
pfil_remove_hook(V_siftr_inet_hook);
|
|
#ifdef SIFTR_IPV6
|
|
pfil_remove_hook(V_siftr_inet6_hook);
|
|
#endif
|
|
}
|
|
CURVNET_RESTORE();
|
|
}
|
|
VNET_LIST_RUNLOCK();
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
siftr_sysctl_logfile_name_handler(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
struct alq *new_alq;
|
|
int error;
|
|
|
|
error = sysctl_handle_string(oidp, arg1, arg2, req);
|
|
|
|
/* Check for error or same filename */
|
|
if (error != 0 || req->newptr == NULL ||
|
|
strncmp(siftr_logfile, arg1, arg2) == 0)
|
|
goto done;
|
|
|
|
/* Filname changed */
|
|
error = alq_open(&new_alq, arg1, curthread->td_ucred,
|
|
SIFTR_LOG_FILE_MODE, SIFTR_ALQ_BUFLEN, 0);
|
|
if (error != 0)
|
|
goto done;
|
|
|
|
/*
|
|
* If disabled, siftr_alq == NULL so we simply close
|
|
* the alq as we've proved it can be opened.
|
|
* If enabled, close the existing alq and switch the old
|
|
* for the new.
|
|
*/
|
|
if (siftr_alq == NULL) {
|
|
alq_close(new_alq);
|
|
} else {
|
|
alq_close(siftr_alq);
|
|
siftr_alq = new_alq;
|
|
}
|
|
|
|
/* Update filename upon success */
|
|
strlcpy(siftr_logfile, arg1, arg2);
|
|
done:
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
siftr_manage_ops(uint8_t action)
|
|
{
|
|
struct siftr_stats totalss;
|
|
struct timeval tval;
|
|
struct flow_hash_node *counter, *tmp_counter;
|
|
struct sbuf *s;
|
|
int i, key_index, error;
|
|
uint32_t bytes_to_write, total_skipped_pkts;
|
|
uint16_t lport, fport;
|
|
uint8_t *key, ipver __unused;
|
|
|
|
#ifdef SIFTR_IPV6
|
|
uint32_t laddr[4];
|
|
uint32_t faddr[4];
|
|
#else
|
|
uint8_t laddr[4];
|
|
uint8_t faddr[4];
|
|
#endif
|
|
|
|
error = 0;
|
|
total_skipped_pkts = 0;
|
|
|
|
/* Init an autosizing sbuf that initially holds 200 chars. */
|
|
if ((s = sbuf_new(NULL, NULL, 200, SBUF_AUTOEXTEND)) == NULL)
|
|
return (-1);
|
|
|
|
if (action == SIFTR_ENABLE && siftr_pkt_manager_thr == NULL) {
|
|
/*
|
|
* Create our alq
|
|
* XXX: We should abort if alq_open fails!
|
|
*/
|
|
alq_open(&siftr_alq, siftr_logfile, curthread->td_ucred,
|
|
SIFTR_LOG_FILE_MODE, SIFTR_ALQ_BUFLEN, 0);
|
|
|
|
STAILQ_INIT(&pkt_queue);
|
|
|
|
DPCPU_ZERO(ss);
|
|
|
|
siftr_exit_pkt_manager_thread = 0;
|
|
|
|
kthread_add(&siftr_pkt_manager_thread, NULL, NULL,
|
|
&siftr_pkt_manager_thr, RFNOWAIT, 0,
|
|
"siftr_pkt_manager_thr");
|
|
|
|
siftr_pfil(HOOK);
|
|
|
|
microtime(&tval);
|
|
|
|
sbuf_printf(s,
|
|
"enable_time_secs=%jd\tenable_time_usecs=%06ld\t"
|
|
"siftrver=%s\thz=%u\ttcp_rtt_scale=%u\tsysname=%s\t"
|
|
"sysver=%u\tipmode=%u\n",
|
|
(intmax_t)tval.tv_sec, tval.tv_usec, MODVERSION_STR, hz,
|
|
TCP_RTT_SCALE, SYS_NAME, __FreeBSD_version, SIFTR_IPMODE);
|
|
|
|
sbuf_finish(s);
|
|
alq_writen(siftr_alq, sbuf_data(s), sbuf_len(s), ALQ_WAITOK);
|
|
|
|
} else if (action == SIFTR_DISABLE && siftr_pkt_manager_thr != NULL) {
|
|
/*
|
|
* Remove the pfil hook functions. All threads currently in
|
|
* the hook functions are allowed to exit before siftr_pfil()
|
|
* returns.
|
|
*/
|
|
siftr_pfil(UNHOOK);
|
|
|
|
/* This will block until the pkt manager thread unlocks it. */
|
|
mtx_lock(&siftr_pkt_mgr_mtx);
|
|
|
|
/* Tell the pkt manager thread that it should exit now. */
|
|
siftr_exit_pkt_manager_thread = 1;
|
|
|
|
/*
|
|
* Wake the pkt_manager thread so it realises that
|
|
* siftr_exit_pkt_manager_thread == 1 and exits gracefully.
|
|
* The wakeup won't be delivered until we unlock
|
|
* siftr_pkt_mgr_mtx so this isn't racy.
|
|
*/
|
|
wakeup(&wait_for_pkt);
|
|
|
|
/* Wait for the pkt_manager thread to exit. */
|
|
mtx_sleep(siftr_pkt_manager_thr, &siftr_pkt_mgr_mtx, PWAIT,
|
|
"thrwait", 0);
|
|
|
|
siftr_pkt_manager_thr = NULL;
|
|
mtx_unlock(&siftr_pkt_mgr_mtx);
|
|
|
|
totalss.n_in = DPCPU_VARSUM(ss, n_in);
|
|
totalss.n_out = DPCPU_VARSUM(ss, n_out);
|
|
totalss.nskip_in_malloc = DPCPU_VARSUM(ss, nskip_in_malloc);
|
|
totalss.nskip_out_malloc = DPCPU_VARSUM(ss, nskip_out_malloc);
|
|
totalss.nskip_in_mtx = DPCPU_VARSUM(ss, nskip_in_mtx);
|
|
totalss.nskip_out_mtx = DPCPU_VARSUM(ss, nskip_out_mtx);
|
|
totalss.nskip_in_tcpcb = DPCPU_VARSUM(ss, nskip_in_tcpcb);
|
|
totalss.nskip_out_tcpcb = DPCPU_VARSUM(ss, nskip_out_tcpcb);
|
|
totalss.nskip_in_inpcb = DPCPU_VARSUM(ss, nskip_in_inpcb);
|
|
totalss.nskip_out_inpcb = DPCPU_VARSUM(ss, nskip_out_inpcb);
|
|
|
|
total_skipped_pkts = totalss.nskip_in_malloc +
|
|
totalss.nskip_out_malloc + totalss.nskip_in_mtx +
|
|
totalss.nskip_out_mtx + totalss.nskip_in_tcpcb +
|
|
totalss.nskip_out_tcpcb + totalss.nskip_in_inpcb +
|
|
totalss.nskip_out_inpcb;
|
|
|
|
microtime(&tval);
|
|
|
|
sbuf_printf(s,
|
|
"disable_time_secs=%jd\tdisable_time_usecs=%06ld\t"
|
|
"num_inbound_tcp_pkts=%ju\tnum_outbound_tcp_pkts=%ju\t"
|
|
"total_tcp_pkts=%ju\tnum_inbound_skipped_pkts_malloc=%u\t"
|
|
"num_outbound_skipped_pkts_malloc=%u\t"
|
|
"num_inbound_skipped_pkts_mtx=%u\t"
|
|
"num_outbound_skipped_pkts_mtx=%u\t"
|
|
"num_inbound_skipped_pkts_tcpcb=%u\t"
|
|
"num_outbound_skipped_pkts_tcpcb=%u\t"
|
|
"num_inbound_skipped_pkts_inpcb=%u\t"
|
|
"num_outbound_skipped_pkts_inpcb=%u\t"
|
|
"total_skipped_tcp_pkts=%u\tflow_list=",
|
|
(intmax_t)tval.tv_sec,
|
|
tval.tv_usec,
|
|
(uintmax_t)totalss.n_in,
|
|
(uintmax_t)totalss.n_out,
|
|
(uintmax_t)(totalss.n_in + totalss.n_out),
|
|
totalss.nskip_in_malloc,
|
|
totalss.nskip_out_malloc,
|
|
totalss.nskip_in_mtx,
|
|
totalss.nskip_out_mtx,
|
|
totalss.nskip_in_tcpcb,
|
|
totalss.nskip_out_tcpcb,
|
|
totalss.nskip_in_inpcb,
|
|
totalss.nskip_out_inpcb,
|
|
total_skipped_pkts);
|
|
|
|
/*
|
|
* Iterate over the flow hash, printing a summary of each
|
|
* flow seen and freeing any malloc'd memory.
|
|
* The hash consists of an array of LISTs (man 3 queue).
|
|
*/
|
|
for (i = 0; i <= siftr_hashmask; i++) {
|
|
LIST_FOREACH_SAFE(counter, counter_hash + i, nodes,
|
|
tmp_counter) {
|
|
key = counter->key;
|
|
key_index = 1;
|
|
|
|
ipver = key[0];
|
|
|
|
memcpy(laddr, key + key_index, sizeof(laddr));
|
|
key_index += sizeof(laddr);
|
|
memcpy(&lport, key + key_index, sizeof(lport));
|
|
key_index += sizeof(lport);
|
|
memcpy(faddr, key + key_index, sizeof(faddr));
|
|
key_index += sizeof(faddr);
|
|
memcpy(&fport, key + key_index, sizeof(fport));
|
|
|
|
#ifdef SIFTR_IPV6
|
|
laddr[3] = ntohl(laddr[3]);
|
|
faddr[3] = ntohl(faddr[3]);
|
|
|
|
if (ipver == INP_IPV6) {
|
|
laddr[0] = ntohl(laddr[0]);
|
|
laddr[1] = ntohl(laddr[1]);
|
|
laddr[2] = ntohl(laddr[2]);
|
|
faddr[0] = ntohl(faddr[0]);
|
|
faddr[1] = ntohl(faddr[1]);
|
|
faddr[2] = ntohl(faddr[2]);
|
|
|
|
sbuf_printf(s,
|
|
"%x:%x:%x:%x:%x:%x:%x:%x;%u-"
|
|
"%x:%x:%x:%x:%x:%x:%x:%x;%u,",
|
|
UPPER_SHORT(laddr[0]),
|
|
LOWER_SHORT(laddr[0]),
|
|
UPPER_SHORT(laddr[1]),
|
|
LOWER_SHORT(laddr[1]),
|
|
UPPER_SHORT(laddr[2]),
|
|
LOWER_SHORT(laddr[2]),
|
|
UPPER_SHORT(laddr[3]),
|
|
LOWER_SHORT(laddr[3]),
|
|
ntohs(lport),
|
|
UPPER_SHORT(faddr[0]),
|
|
LOWER_SHORT(faddr[0]),
|
|
UPPER_SHORT(faddr[1]),
|
|
LOWER_SHORT(faddr[1]),
|
|
UPPER_SHORT(faddr[2]),
|
|
LOWER_SHORT(faddr[2]),
|
|
UPPER_SHORT(faddr[3]),
|
|
LOWER_SHORT(faddr[3]),
|
|
ntohs(fport));
|
|
} else {
|
|
laddr[0] = FIRST_OCTET(laddr[3]);
|
|
laddr[1] = SECOND_OCTET(laddr[3]);
|
|
laddr[2] = THIRD_OCTET(laddr[3]);
|
|
laddr[3] = FOURTH_OCTET(laddr[3]);
|
|
faddr[0] = FIRST_OCTET(faddr[3]);
|
|
faddr[1] = SECOND_OCTET(faddr[3]);
|
|
faddr[2] = THIRD_OCTET(faddr[3]);
|
|
faddr[3] = FOURTH_OCTET(faddr[3]);
|
|
#endif
|
|
sbuf_printf(s,
|
|
"%u.%u.%u.%u;%u-%u.%u.%u.%u;%u,",
|
|
laddr[0],
|
|
laddr[1],
|
|
laddr[2],
|
|
laddr[3],
|
|
ntohs(lport),
|
|
faddr[0],
|
|
faddr[1],
|
|
faddr[2],
|
|
faddr[3],
|
|
ntohs(fport));
|
|
#ifdef SIFTR_IPV6
|
|
}
|
|
#endif
|
|
|
|
free(counter, M_SIFTR_HASHNODE);
|
|
}
|
|
|
|
LIST_INIT(counter_hash + i);
|
|
}
|
|
|
|
sbuf_printf(s, "\n");
|
|
sbuf_finish(s);
|
|
|
|
i = 0;
|
|
do {
|
|
bytes_to_write = min(SIFTR_ALQ_BUFLEN, sbuf_len(s)-i);
|
|
alq_writen(siftr_alq, sbuf_data(s)+i, bytes_to_write, ALQ_WAITOK);
|
|
i += bytes_to_write;
|
|
} while (i < sbuf_len(s));
|
|
|
|
alq_close(siftr_alq);
|
|
siftr_alq = NULL;
|
|
} else
|
|
error = EINVAL;
|
|
|
|
sbuf_delete(s);
|
|
|
|
/*
|
|
* XXX: Should be using ret to check if any functions fail
|
|
* and set error appropriately
|
|
*/
|
|
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
siftr_sysctl_enabled_handler(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
int error;
|
|
uint32_t new;
|
|
|
|
new = siftr_enabled;
|
|
error = sysctl_handle_int(oidp, &new, 0, req);
|
|
if (error == 0 && req->newptr != NULL) {
|
|
if (new > 1)
|
|
return (EINVAL);
|
|
else if (new != siftr_enabled) {
|
|
if ((error = siftr_manage_ops(new)) == 0) {
|
|
siftr_enabled = new;
|
|
} else {
|
|
siftr_manage_ops(SIFTR_DISABLE);
|
|
}
|
|
}
|
|
}
|
|
|
|
return (error);
|
|
}
|
|
|
|
static void
|
|
siftr_shutdown_handler(void *arg)
|
|
{
|
|
if (siftr_enabled == 1) {
|
|
siftr_manage_ops(SIFTR_DISABLE);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Module is being unloaded or machine is shutting down. Take care of cleanup.
|
|
*/
|
|
static int
|
|
deinit_siftr(void)
|
|
{
|
|
/* Cleanup. */
|
|
siftr_manage_ops(SIFTR_DISABLE);
|
|
hashdestroy(counter_hash, M_SIFTR, siftr_hashmask);
|
|
mtx_destroy(&siftr_pkt_queue_mtx);
|
|
mtx_destroy(&siftr_pkt_mgr_mtx);
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Module has just been loaded into the kernel.
|
|
*/
|
|
static int
|
|
init_siftr(void)
|
|
{
|
|
EVENTHANDLER_REGISTER(shutdown_pre_sync, siftr_shutdown_handler, NULL,
|
|
SHUTDOWN_PRI_FIRST);
|
|
|
|
/* Initialise our flow counter hash table. */
|
|
counter_hash = hashinit(SIFTR_EXPECTED_MAX_TCP_FLOWS, M_SIFTR,
|
|
&siftr_hashmask);
|
|
|
|
mtx_init(&siftr_pkt_queue_mtx, "siftr_pkt_queue_mtx", NULL, MTX_DEF);
|
|
mtx_init(&siftr_pkt_mgr_mtx, "siftr_pkt_mgr_mtx", NULL, MTX_DEF);
|
|
|
|
/* Print message to the user's current terminal. */
|
|
uprintf("\nStatistical Information For TCP Research (SIFTR) %s\n"
|
|
" http://caia.swin.edu.au/urp/newtcp\n\n",
|
|
MODVERSION_STR);
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* This is the function that is called to load and unload the module.
|
|
* When the module is loaded, this function is called once with
|
|
* "what" == MOD_LOAD
|
|
* When the module is unloaded, this function is called twice with
|
|
* "what" = MOD_QUIESCE first, followed by "what" = MOD_UNLOAD second
|
|
* When the system is shut down e.g. CTRL-ALT-DEL or using the shutdown command,
|
|
* this function is called once with "what" = MOD_SHUTDOWN
|
|
* When the system is shut down, the handler isn't called until the very end
|
|
* of the shutdown sequence i.e. after the disks have been synced.
|
|
*/
|
|
static int
|
|
siftr_load_handler(module_t mod, int what, void *arg)
|
|
{
|
|
int ret;
|
|
|
|
switch (what) {
|
|
case MOD_LOAD:
|
|
ret = init_siftr();
|
|
break;
|
|
|
|
case MOD_QUIESCE:
|
|
case MOD_SHUTDOWN:
|
|
ret = deinit_siftr();
|
|
break;
|
|
|
|
case MOD_UNLOAD:
|
|
ret = 0;
|
|
break;
|
|
|
|
default:
|
|
ret = EINVAL;
|
|
break;
|
|
}
|
|
|
|
return (ret);
|
|
}
|
|
|
|
static moduledata_t siftr_mod = {
|
|
.name = "siftr",
|
|
.evhand = siftr_load_handler,
|
|
};
|
|
|
|
/*
|
|
* Param 1: name of the kernel module
|
|
* Param 2: moduledata_t struct containing info about the kernel module
|
|
* and the execution entry point for the module
|
|
* Param 3: From sysinit_sub_id enumeration in /usr/include/sys/kernel.h
|
|
* Defines the module initialisation order
|
|
* Param 4: From sysinit_elem_order enumeration in /usr/include/sys/kernel.h
|
|
* Defines the initialisation order of this kld relative to others
|
|
* within the same subsystem as defined by param 3
|
|
*/
|
|
DECLARE_MODULE(siftr, siftr_mod, SI_SUB_LAST, SI_ORDER_ANY);
|
|
MODULE_DEPEND(siftr, alq, 1, 1, 1);
|
|
MODULE_VERSION(siftr, MODVERSION);
|