freebsd-skq/sys/netipsec/xform_tcp.c
rwatson 57ca4583e7 Build on Jeff Roberson's linker-set based dynamic per-CPU allocator
(DPCPU), as suggested by Peter Wemm, and implement a new per-virtual
network stack memory allocator.  Modify vnet to use the allocator
instead of monolithic global container structures (vinet, ...).  This
change solves many binary compatibility problems associated with
VIMAGE, and restores ELF symbols for virtualized global variables.

Each virtualized global variable exists as a "reference copy", and also
once per virtual network stack.  Virtualized global variables are
tagged at compile-time, placing the in a special linker set, which is
loaded into a contiguous region of kernel memory.  Virtualized global
variables in the base kernel are linked as normal, but those in modules
are copied and relocated to a reserved portion of the kernel's vnet
region with the help of a the kernel linker.

Virtualized global variables exist in per-vnet memory set up when the
network stack instance is created, and are initialized statically from
the reference copy.  Run-time access occurs via an accessor macro, which
converts from the current vnet and requested symbol to a per-vnet
address.  When "options VIMAGE" is not compiled into the kernel, normal
global ELF symbols will be used instead and indirection is avoided.

This change restores static initialization for network stack global
variables, restores support for non-global symbols and types, eliminates
the need for many subsystem constructors, eliminates large per-subsystem
structures that caused many binary compatibility issues both for
monitoring applications (netstat) and kernel modules, removes the
per-function INIT_VNET_*() macros throughout the stack, eliminates the
need for vnet_symmap ksym(2) munging, and eliminates duplicate
definitions of virtualized globals under VIMAGE_GLOBALS.

Bump __FreeBSD_version and update UPDATING.

Portions submitted by:  bz
Reviewed by:            bz, zec
Discussed with:         gnn, jamie, jeff, jhb, julian, sam
Suggested by:           peter
Approved by:            re (kensmith)
2009-07-14 22:48:30 +00:00

173 lines
4.7 KiB
C

/* $FreeBSD$ */
/*-
* Copyright (c) 2003 Bruce M. Simpson <bms@spc.org>
*
* 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.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
*/
/* TCP MD5 Signature Option (RFC2385) */
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/lock.h>
#include <sys/socket.h>
#include <sys/kernel.h>
#include <sys/protosw.h>
#include <sys/sysctl.h>
#include <sys/vimage.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/tcp.h>
#include <netinet/tcp_var.h>
#include <net/route.h>
#include <net/vnet.h>
#include <netipsec/ipsec.h>
#include <netipsec/xform.h>
#ifdef INET6
#include <netinet/ip6.h>
#include <netipsec/ipsec6.h>
#endif
#include <netipsec/key.h>
#include <netipsec/key_debug.h>
/*
* Initialize a TCP-MD5 SA. Called when the SA is being set up.
*
* We don't need to set up the tdb prefixed fields, as we don't use the
* opencrypto code; we just perform a key length check.
*
* XXX: Currently we only allow a single 'magic' SPI to be used.
*
* This allows per-host granularity without affecting the userland
* interface, which is a simple socket option toggle switch,
* TCP_SIGNATURE_ENABLE.
*
* To allow per-service granularity requires that we have a means
* of mapping port to SPI. The mandated way of doing this is to
* use SPD entries to specify packet flows which get the TCP-MD5
* treatment, however the code to do this is currently unstable
* and unsuitable for production use.
*
* Therefore we use this compromise in the meantime.
*/
static int
tcpsignature_init(struct secasvar *sav, struct xformsw *xsp)
{
int keylen;
if (sav->spi != htonl(TCP_SIG_SPI)) {
DPRINTF(("%s: SPI must be TCP_SIG_SPI (0x1000)\n",
__func__));
return (EINVAL);
}
if (sav->alg_auth != SADB_X_AALG_TCP_MD5) {
DPRINTF(("%s: unsupported authentication algorithm %u\n",
__func__, sav->alg_auth));
return (EINVAL);
}
if (sav->key_auth == NULL) {
DPRINTF(("%s: no authentication key present\n", __func__));
return (EINVAL);
}
keylen = _KEYLEN(sav->key_auth);
if ((keylen < TCP_KEYLEN_MIN) || (keylen > TCP_KEYLEN_MAX)) {
DPRINTF(("%s: invalid key length %u\n", __func__, keylen));
return (EINVAL);
}
return (0);
}
/*
* Paranoia.
*
* Called when the SA is deleted.
*/
static int
tcpsignature_zeroize(struct secasvar *sav)
{
if (sav->key_auth)
bzero(sav->key_auth->key_data, _KEYLEN(sav->key_auth));
sav->tdb_cryptoid = 0;
sav->tdb_authalgxform = NULL;
sav->tdb_xform = NULL;
return (0);
}
/*
* Verify that an input packet passes authentication.
* Called from the ipsec layer.
* We do this from within tcp itself, so this routine is just a stub.
*/
static int
tcpsignature_input(struct mbuf *m, struct secasvar *sav, int skip,
int protoff)
{
return (0);
}
/*
* Prepend the authentication header.
* Called from the ipsec layer.
* We do this from within tcp itself, so this routine is just a stub.
*/
static int
tcpsignature_output(struct mbuf *m, struct ipsecrequest *isr,
struct mbuf **mp, int skip, int protoff)
{
return (EINVAL);
}
static struct xformsw tcpsignature_xformsw = {
XF_TCPSIGNATURE, XFT_AUTH, "TCPMD5",
tcpsignature_init, tcpsignature_zeroize,
tcpsignature_input, tcpsignature_output
};
static void
tcpsignature_attach(void)
{
xform_register(&tcpsignature_xformsw);
}
SYSINIT(tcpsignature_xform_init, SI_SUB_DRIVERS, SI_ORDER_FIRST,
tcpsignature_attach, NULL);