This file was erroneously removed from HEAD when TCP-MD5 support was MFC'd;

correct this lameness.

1 files changed, 169 insertions, 0 deletions

diff --git a/sys/netipsec/xform_tcp.c b/sys/netipsec/xform_tcp.c
new file mode 100644
index 0000000..e505596
--- /dev/null
+++ b/sys/netipsec/xform_tcp.c
@@ -0,0 +1,169 @@
+/*	$FreeBSD$ */
+
+/*
+ * 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 <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 <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__, sav->alg_auth));
+		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(_KEYBUF(sav->key_auth), _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)