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c82ed437c6
freebsd/sys/netinet/tcp_subr.c
Gleb Smirnoff fb7c1ac5ac tcp: remove the looping on pcb count in tcp_destroy() 
This was useful when TCP timers were not able to reliably stop. Note that
in_pcbinfo_destroy() called later asserts that V_tcbinfo.ipi_count is 0.

This reverts 806929d514, b54e08e11a.
2024-11-14 11:39:12 -08:00

4784 lines
127 KiB
C
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/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
* The Regents of the University of California. 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.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*/
#include <sys/cdefs.h>
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ipsec.h"
#include "opt_kern_tls.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/arb.h>
#include <sys/callout.h>
#include <sys/eventhandler.h>
#ifdef TCP_HHOOK
#include <sys/hhook.h>
#endif
#include <sys/kernel.h>
#ifdef TCP_HHOOK
#include <sys/khelp.h>
#endif
#ifdef KERN_TLS
#include <sys/ktls.h>
#endif
#include <sys/qmath.h>
#include <sys/stats.h>
#include <sys/sysctl.h>
#include <sys/jail.h>
#include <sys/malloc.h>
#include <sys/refcount.h>
#include <sys/mbuf.h>
#include <sys/priv.h>
#include <sys/sdt.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/protosw.h>
#include <sys/random.h>
#include <vm/uma.h>
#include <net/route.h>
#include <net/route/nhop.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_private.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/in_fib.h>
#include <netinet/in_kdtrace.h>
#include <netinet/in_pcb.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include <netinet/ip_var.h>
#ifdef INET6
#include <netinet/icmp6.h>
#include <netinet/ip6.h>
#include <netinet6/in6_fib.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/ip6_var.h>
#include <netinet6/scope6_var.h>
#include <netinet6/nd6.h>
#endif
#include <netinet/tcp.h>
#ifdef INVARIANTS
#define TCPSTATES
#endif
#include <netinet/tcp_fsm.h>
#include <netinet/tcp_seq.h>
#include <netinet/tcp_timer.h>
#include <netinet/tcp_var.h>
#include <netinet/tcp_ecn.h>
#include <netinet/tcp_log_buf.h>
#include <netinet/tcp_syncache.h>
#include <netinet/tcp_hpts.h>
#include <netinet/tcp_lro.h>
#include <netinet/cc/cc.h>
#include <netinet/tcpip.h>
#include <netinet/tcp_fastopen.h>
#include <netinet/tcp_accounting.h>
#ifdef TCPPCAP
#include <netinet/tcp_pcap.h>
#endif
#ifdef TCP_OFFLOAD
#include <netinet/tcp_offload.h>
#endif
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#ifdef INET6
#include <netinet6/tcp6_var.h>
#endif
#include <netipsec/ipsec_support.h>
#include <machine/in_cksum.h>
#include <crypto/siphash/siphash.h>
#include <security/mac/mac_framework.h>
#ifdef INET6
static ip6proto_ctlinput_t tcp6_ctlinput;
static udp_tun_icmp_t tcp6_ctlinput_viaudp;
#endif
VNET_DEFINE(int, tcp_mssdflt) = TCP_MSS;
#ifdef INET6
VNET_DEFINE(int, tcp_v6mssdflt) = TCP6_MSS;
#endif
VNET_DEFINE(uint32_t, tcp_ack_war_time_window) = 1000;
SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_timewindow,
CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_ack_war_time_window), 0,
"Time interval in ms used to limit the number (ack_war_cnt) of challenge ACKs sent per TCP connection");
VNET_DEFINE(uint32_t, tcp_ack_war_cnt) = 5;
SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_cnt, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(tcp_ack_war_cnt), 0,
"Maximum number of challenge ACKs sent per TCP connection during the time interval (ack_war_timewindow)");
struct rwlock tcp_function_lock;
static int
sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS)
{
int error, new;
new = V_tcp_mssdflt;
error = sysctl_handle_int(oidp, &new, 0, req);
if (error == 0 && req->newptr) {
if (new < TCP_MINMSS)
error = EINVAL;
else
V_tcp_mssdflt = new;
}
return (error);
}
SYSCTL_PROC(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt,
CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
&VNET_NAME(tcp_mssdflt), 0, &sysctl_net_inet_tcp_mss_check, "I",
"Default TCP Maximum Segment Size");
#ifdef INET6
static int
sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS)
{
int error, new;
new = V_tcp_v6mssdflt;
error = sysctl_handle_int(oidp, &new, 0, req);
if (error == 0 && req->newptr) {
if (new < TCP_MINMSS)
error = EINVAL;
else
V_tcp_v6mssdflt = new;
}
return (error);
}
SYSCTL_PROC(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt,
CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
&VNET_NAME(tcp_v6mssdflt), 0, &sysctl_net_inet_tcp_mss_v6_check, "I",
"Default TCP Maximum Segment Size for IPv6");
#endif /* INET6 */
/*
* Minimum MSS we accept and use. This prevents DoS attacks where
* we are forced to a ridiculous low MSS like 20 and send hundreds
* of packets instead of one. The effect scales with the available
* bandwidth and quickly saturates the CPU and network interface
* with packet generation and sending. Set to zero to disable MINMSS
* checking. This setting prevents us from sending too small packets.
*/
VNET_DEFINE(int, tcp_minmss) = TCP_MINMSS;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(tcp_minmss), 0,
"Minimum TCP Maximum Segment Size");
VNET_DEFINE(int, tcp_do_rfc1323) = 1;
SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(tcp_do_rfc1323), 0,
"Enable rfc1323 (high performance TCP) extensions");
/*
* As of June 2021, several TCP stacks violate RFC 7323 from September 2014.
* Some stacks negotiate TS, but never send them after connection setup. Some
* stacks negotiate TS, but don't send them when sending keep-alive segments.
* These include modern widely deployed TCP stacks.
* Therefore tolerating violations for now...
*/
VNET_DEFINE(int, tcp_tolerate_missing_ts) = 1;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, tolerate_missing_ts, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(tcp_tolerate_missing_ts), 0,
"Tolerate missing TCP timestamps");
VNET_DEFINE(int, tcp_ts_offset_per_conn) = 1;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, ts_offset_per_conn, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(tcp_ts_offset_per_conn), 0,
"Initialize TCP timestamps per connection instead of per host pair");
/* How many connections are pacing */
static volatile uint32_t number_of_tcp_connections_pacing = 0;
static uint32_t shadow_num_connections = 0;
static counter_u64_t tcp_pacing_failures;
static counter_u64_t tcp_dgp_failures;
static uint32_t shadow_tcp_pacing_dgp = 0;
static volatile uint32_t number_of_dgp_connections = 0;
static int tcp_pacing_limit = 10000;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, pacing_limit, CTLFLAG_RW,
&tcp_pacing_limit, 1000,
"If the TCP stack does pacing, is there a limit (-1 = no, 0 = no pacing N = number of connections)");
static int tcp_dgp_limit = -1;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, dgp_limit, CTLFLAG_RW,
&tcp_dgp_limit, -1,
"If the TCP stack does DGP, is there a limit (-1 = no, 0 = no dgp N = number of connections)");
SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pacing_count, CTLFLAG_RD,
&shadow_num_connections, 0, "Number of TCP connections being paced");
SYSCTL_COUNTER_U64(_net_inet_tcp, OID_AUTO, pacing_failures, CTLFLAG_RD,
&tcp_pacing_failures, "Number of times we failed to enable pacing to avoid exceeding the limit");
SYSCTL_COUNTER_U64(_net_inet_tcp, OID_AUTO, dgp_failures, CTLFLAG_RD,
&tcp_dgp_failures, "Number of times we failed to enable dgp to avoid exceeding the limit");
static int tcp_log_debug = 0;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_debug, CTLFLAG_RW,
&tcp_log_debug, 0, "Log errors caused by incoming TCP segments");
/*
* Target size of TCP PCB hash tables. Must be a power of two.
*
* Note that this can be overridden by the kernel environment
* variable net.inet.tcp.tcbhashsize
*/
#ifndef TCBHASHSIZE
#define TCBHASHSIZE 0
#endif
static int tcp_tcbhashsize = TCBHASHSIZE;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN,
&tcp_tcbhashsize, 0, "Size of TCP control-block hashtable");
static int do_tcpdrain = 1;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0,
"Enable tcp_drain routine for extra help when low on mbufs");
SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_VNET | CTLFLAG_RD,
&VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs");
VNET_DEFINE_STATIC(int, icmp_may_rst) = 1;
#define V_icmp_may_rst VNET(icmp_may_rst)
SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(icmp_may_rst), 0,
"Certain ICMP unreachable messages may abort connections in SYN_SENT");
VNET_DEFINE_STATIC(int, tcp_isn_reseed_interval) = 0;
#define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval)
SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(tcp_isn_reseed_interval), 0,
"Seconds between reseeding of ISN secret");
static int tcp_soreceive_stream;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, soreceive_stream, CTLFLAG_RDTUN,
&tcp_soreceive_stream, 0, "Using soreceive_stream for TCP sockets");
VNET_DEFINE(uma_zone_t, sack_hole_zone);
#define V_sack_hole_zone VNET(sack_hole_zone)
VNET_DEFINE(uint32_t, tcp_map_entries_limit) = 0; /* unlimited */
static int
sysctl_net_inet_tcp_map_limit_check(SYSCTL_HANDLER_ARGS)
{
int error;
uint32_t new;
new = V_tcp_map_entries_limit;
error = sysctl_handle_int(oidp, &new, 0, req);
if (error == 0 && req->newptr) {
/* only allow "0" and value > minimum */
if (new > 0 && new < TCP_MIN_MAP_ENTRIES_LIMIT)
error = EINVAL;
else
V_tcp_map_entries_limit = new;
}
return (error);
}
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, map_limit,
CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
&VNET_NAME(tcp_map_entries_limit), 0,
&sysctl_net_inet_tcp_map_limit_check, "IU",
"Total sendmap entries limit");
VNET_DEFINE(uint32_t, tcp_map_split_limit) = 0; /* unlimited */
SYSCTL_UINT(_net_inet_tcp, OID_AUTO, split_limit, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(tcp_map_split_limit), 0,
"Total sendmap split entries limit");
#ifdef TCP_HHOOK
VNET_DEFINE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST+1]);
#endif
#define TS_OFFSET_SECRET_LENGTH SIPHASH_KEY_LENGTH
VNET_DEFINE_STATIC(u_char, ts_offset_secret[TS_OFFSET_SECRET_LENGTH]);
#define V_ts_offset_secret VNET(ts_offset_secret)
static int tcp_default_fb_init(struct tcpcb *tp, void **ptr);
static void tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged);
static int tcp_default_handoff_ok(struct tcpcb *tp);
static struct inpcb *tcp_notify(struct inpcb *, int);
static struct inpcb *tcp_mtudisc_notify(struct inpcb *, int);
static struct inpcb *tcp_mtudisc(struct inpcb *, int);
static struct inpcb *tcp_drop_syn_sent(struct inpcb *, int);
static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th,
const void *ip4hdr, const void *ip6hdr);
static void tcp_default_switch_failed(struct tcpcb *tp);
static ipproto_ctlinput_t tcp_ctlinput;
static udp_tun_icmp_t tcp_ctlinput_viaudp;
static struct tcp_function_block tcp_def_funcblk = {
.tfb_tcp_block_name = "freebsd",
.tfb_tcp_output = tcp_default_output,
.tfb_tcp_do_segment = tcp_do_segment,
.tfb_tcp_ctloutput = tcp_default_ctloutput,
.tfb_tcp_handoff_ok = tcp_default_handoff_ok,
.tfb_tcp_fb_init = tcp_default_fb_init,
.tfb_tcp_fb_fini = tcp_default_fb_fini,
.tfb_switch_failed = tcp_default_switch_failed,
.tfb_flags = TCP_FUNC_DEFAULT_OK,
};
static int tcp_fb_cnt = 0;
struct tcp_funchead t_functions;
VNET_DEFINE_STATIC(struct tcp_function_block *, tcp_func_set_ptr) = &tcp_def_funcblk;
#define V_tcp_func_set_ptr VNET(tcp_func_set_ptr)
void
tcp_record_dsack(struct tcpcb *tp, tcp_seq start, tcp_seq end, int tlp)
{
TCPSTAT_INC(tcps_dsack_count);
tp->t_dsack_pack++;
if (tlp == 0) {
if (SEQ_GT(end, start)) {
tp->t_dsack_bytes += (end - start);
TCPSTAT_ADD(tcps_dsack_bytes, (end - start));
} else {
tp->t_dsack_tlp_bytes += (start - end);
TCPSTAT_ADD(tcps_dsack_bytes, (start - end));
}
} else {
if (SEQ_GT(end, start)) {
tp->t_dsack_bytes += (end - start);
TCPSTAT_ADD(tcps_dsack_tlp_bytes, (end - start));
} else {
tp->t_dsack_tlp_bytes += (start - end);
TCPSTAT_ADD(tcps_dsack_tlp_bytes, (start - end));
}
}
}
static struct tcp_function_block *
find_tcp_functions_locked(struct tcp_function_set *fs)
{
struct tcp_function *f;
struct tcp_function_block *blk = NULL;
rw_assert(&tcp_function_lock, RA_LOCKED);
TAILQ_FOREACH(f, &t_functions, tf_next) {
if (strcmp(f->tf_name, fs->function_set_name) == 0) {
blk = f->tf_fb;
break;
}
}
return (blk);
}
static struct tcp_function_block *
find_tcp_fb_locked(struct tcp_function_block *blk, struct tcp_function **s)
{
struct tcp_function_block *rblk = NULL;
struct tcp_function *f;
rw_assert(&tcp_function_lock, RA_LOCKED);
TAILQ_FOREACH(f, &t_functions, tf_next) {
if (f->tf_fb == blk) {
rblk = blk;
if (s) {
*s = f;
}
break;
}
}
return (rblk);
}
struct tcp_function_block *
find_and_ref_tcp_functions(struct tcp_function_set *fs)
{
struct tcp_function_block *blk;
rw_rlock(&tcp_function_lock);
blk = find_tcp_functions_locked(fs);
if (blk)
refcount_acquire(&blk->tfb_refcnt);
rw_runlock(&tcp_function_lock);
return (blk);
}
struct tcp_function_block *
find_and_ref_tcp_fb(struct tcp_function_block *blk)
{
struct tcp_function_block *rblk;
rw_rlock(&tcp_function_lock);
rblk = find_tcp_fb_locked(blk, NULL);
if (rblk)
refcount_acquire(&rblk->tfb_refcnt);
rw_runlock(&tcp_function_lock);
return (rblk);
}
/* Find a matching alias for the given tcp_function_block. */
int
find_tcp_function_alias(struct tcp_function_block *blk,
struct tcp_function_set *fs)
{
struct tcp_function *f;
int found;
found = 0;
rw_rlock(&tcp_function_lock);
TAILQ_FOREACH(f, &t_functions, tf_next) {
if ((f->tf_fb == blk) &&
(strncmp(f->tf_name, blk->tfb_tcp_block_name,
TCP_FUNCTION_NAME_LEN_MAX) != 0)) {
/* Matching function block with different name. */
strncpy(fs->function_set_name, f->tf_name,
TCP_FUNCTION_NAME_LEN_MAX);
found = 1;
break;
}
}
/* Null terminate the string appropriately. */
if (found) {
fs->function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0';
} else {
fs->function_set_name[0] = '\0';
}
rw_runlock(&tcp_function_lock);
return (found);
}
static struct tcp_function_block *
find_and_ref_tcp_default_fb(void)
{
struct tcp_function_block *rblk;
rw_rlock(&tcp_function_lock);
rblk = V_tcp_func_set_ptr;
refcount_acquire(&rblk->tfb_refcnt);
rw_runlock(&tcp_function_lock);
return (rblk);
}
void
tcp_switch_back_to_default(struct tcpcb *tp)
{
struct tcp_function_block *tfb;
void *ptr = NULL;
KASSERT(tp->t_fb != &tcp_def_funcblk,
("%s: called by the built-in default stack", __func__));
if (tp->t_fb->tfb_tcp_timer_stop_all != NULL)
tp->t_fb->tfb_tcp_timer_stop_all(tp);
/*
* Now, we'll find a new function block to use.
* Start by trying the current user-selected
* default, unless this stack is the user-selected
* default.
*/
tfb = find_and_ref_tcp_default_fb();
if (tfb == tp->t_fb) {
refcount_release(&tfb->tfb_refcnt);
tfb = NULL;
}
/* Does the stack accept this connection? */
if (tfb != NULL && (*tfb->tfb_tcp_handoff_ok)(tp)) {
refcount_release(&tfb->tfb_refcnt);
tfb = NULL;
}
/* Try to use that stack. */
if (tfb != NULL) {
/* Initialize the new stack. If it succeeds, we are done. */
if (tfb->tfb_tcp_fb_init == NULL ||
(*tfb->tfb_tcp_fb_init)(tp, &ptr) == 0) {
/* Release the old stack */
if (tp->t_fb->tfb_tcp_fb_fini != NULL)
(*tp->t_fb->tfb_tcp_fb_fini)(tp, 0);
refcount_release(&tp->t_fb->tfb_refcnt);
/* Now set in all the pointers */
tp->t_fb = tfb;
tp->t_fb_ptr = ptr;
return;
}
/*
* Initialization failed. Release the reference count on
* the looked up default stack.
*/
refcount_release(&tfb->tfb_refcnt);
}
/*
* If that wasn't feasible, use the built-in default
* stack which is not allowed to reject anyone.
*/
tfb = find_and_ref_tcp_fb(&tcp_def_funcblk);
if (tfb == NULL) {
/* there always should be a default */
panic("Can't refer to tcp_def_funcblk");
}
if ((*tfb->tfb_tcp_handoff_ok)(tp)) {
/* The default stack cannot say no */
panic("Default stack rejects a new session?");
}
if (tfb->tfb_tcp_fb_init != NULL &&
(*tfb->tfb_tcp_fb_init)(tp, &ptr)) {
/* The default stack cannot fail */
panic("Default stack initialization failed");
}
/* Now release the old stack */
if (tp->t_fb->tfb_tcp_fb_fini != NULL)
(*tp->t_fb->tfb_tcp_fb_fini)(tp, 0);
refcount_release(&tp->t_fb->tfb_refcnt);
/* And set in the pointers to the new */
tp->t_fb = tfb;
tp->t_fb_ptr = ptr;
}
static bool
tcp_recv_udp_tunneled_packet(struct mbuf *m, int off, struct inpcb *inp,
const struct sockaddr *sa, void *ctx)
{
struct ip *iph;
#ifdef INET6
struct ip6_hdr *ip6;
#endif
struct udphdr *uh;
struct tcphdr *th;
int thlen;
uint16_t port;
TCPSTAT_INC(tcps_tunneled_pkts);
if ((m->m_flags & M_PKTHDR) == 0) {
/* Can't handle one that is not a pkt hdr */
TCPSTAT_INC(tcps_tunneled_errs);
goto out;
}
thlen = sizeof(struct tcphdr);
if (m->m_len < off + sizeof(struct udphdr) + thlen &&
(m = m_pullup(m, off + sizeof(struct udphdr) + thlen)) == NULL) {
TCPSTAT_INC(tcps_tunneled_errs);
goto out;
}
iph = mtod(m, struct ip *);
uh = (struct udphdr *)((caddr_t)iph + off);
th = (struct tcphdr *)(uh + 1);
thlen = th->th_off << 2;
if (m->m_len < off + sizeof(struct udphdr) + thlen) {
m = m_pullup(m, off + sizeof(struct udphdr) + thlen);
if (m == NULL) {
TCPSTAT_INC(tcps_tunneled_errs);
goto out;
} else {
iph = mtod(m, struct ip *);
uh = (struct udphdr *)((caddr_t)iph + off);
th = (struct tcphdr *)(uh + 1);
}
}
m->m_pkthdr.tcp_tun_port = port = uh->uh_sport;
bcopy(th, uh, m->m_len - off);
m->m_len -= sizeof(struct udphdr);
m->m_pkthdr.len -= sizeof(struct udphdr);
/*
* We use the same algorithm for
* both UDP and TCP for c-sum. So
* the code in tcp_input will skip
* the checksum. So we do nothing
* with the flag (m->m_pkthdr.csum_flags).
*/
switch (iph->ip_v) {
#ifdef INET
case IPVERSION:
iph->ip_len = htons(ntohs(iph->ip_len) - sizeof(struct udphdr));
tcp_input_with_port(&m, &off, IPPROTO_TCP, port);
break;
#endif
#ifdef INET6
case IPV6_VERSION >> 4:
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - sizeof(struct udphdr));
tcp6_input_with_port(&m, &off, IPPROTO_TCP, port);
break;
#endif
default:
goto out;
break;
}
return (true);
out:
m_freem(m);
return (true);
}
static int
sysctl_net_inet_default_tcp_functions(SYSCTL_HANDLER_ARGS)
{
int error = ENOENT;
struct tcp_function_set fs;
struct tcp_function_block *blk;
memset(&fs, 0, sizeof(fs));
rw_rlock(&tcp_function_lock);
blk = find_tcp_fb_locked(V_tcp_func_set_ptr, NULL);
if (blk) {
/* Found him */
strcpy(fs.function_set_name, blk->tfb_tcp_block_name);
fs.pcbcnt = blk->tfb_refcnt;
}
rw_runlock(&tcp_function_lock);
error = sysctl_handle_string(oidp, fs.function_set_name,
sizeof(fs.function_set_name), req);
/* Check for error or no change */
if (error != 0 || req->newptr == NULL)
return (error);
rw_wlock(&tcp_function_lock);
blk = find_tcp_functions_locked(&fs);
if ((blk == NULL) ||
(blk->tfb_flags & TCP_FUNC_BEING_REMOVED)) {
error = ENOENT;
goto done;
}
if ((blk->tfb_flags & TCP_FUNC_DEFAULT_OK) == 0) {
error = EINVAL;
goto done;
}
V_tcp_func_set_ptr = blk;
done:
rw_wunlock(&tcp_function_lock);
return (error);
}
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_default,
CTLFLAG_VNET | CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
NULL, 0, sysctl_net_inet_default_tcp_functions, "A",
"Set/get the default TCP functions");
static int
sysctl_net_inet_list_available(SYSCTL_HANDLER_ARGS)
{
int error, cnt, linesz;
struct tcp_function *f;
char *buffer, *cp;
size_t bufsz, outsz;
bool alias;
cnt = 0;
rw_rlock(&tcp_function_lock);
TAILQ_FOREACH(f, &t_functions, tf_next) {
cnt++;
}
rw_runlock(&tcp_function_lock);
bufsz = (cnt+2) * ((TCP_FUNCTION_NAME_LEN_MAX * 2) + 13) + 1;
buffer = malloc(bufsz, M_TEMP, M_WAITOK);
error = 0;
cp = buffer;
linesz = snprintf(cp, bufsz, "\n%-32s%c %-32s %s\n", "Stack", 'D',
"Alias", "PCB count");
cp += linesz;
bufsz -= linesz;
outsz = linesz;
rw_rlock(&tcp_function_lock);
TAILQ_FOREACH(f, &t_functions, tf_next) {
alias = (f->tf_name != f->tf_fb->tfb_tcp_block_name);
linesz = snprintf(cp, bufsz, "%-32s%c %-32s %u\n",
f->tf_fb->tfb_tcp_block_name,
(f->tf_fb == V_tcp_func_set_ptr) ? '*' : ' ',
alias ? f->tf_name : "-",
f->tf_fb->tfb_refcnt);
if (linesz >= bufsz) {
error = EOVERFLOW;
break;
}
cp += linesz;
bufsz -= linesz;
outsz += linesz;
}
rw_runlock(&tcp_function_lock);
if (error == 0)
error = sysctl_handle_string(oidp, buffer, outsz + 1, req);
free(buffer, M_TEMP);
return (error);
}
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_available,
CTLFLAG_VNET | CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
NULL, 0, sysctl_net_inet_list_available, "A",
"list available TCP Function sets");
VNET_DEFINE(int, tcp_udp_tunneling_port) = TCP_TUNNELING_PORT_DEFAULT;
#ifdef INET
VNET_DEFINE(struct socket *, udp4_tun_socket) = NULL;
#define V_udp4_tun_socket VNET(udp4_tun_socket)
#endif
#ifdef INET6
VNET_DEFINE(struct socket *, udp6_tun_socket) = NULL;
#define V_udp6_tun_socket VNET(udp6_tun_socket)
#endif
static struct sx tcpoudp_lock;
static void
tcp_over_udp_stop(void)
{
sx_assert(&tcpoudp_lock, SA_XLOCKED);
#ifdef INET
if (V_udp4_tun_socket != NULL) {
soclose(V_udp4_tun_socket);
V_udp4_tun_socket = NULL;
}
#endif
#ifdef INET6
if (V_udp6_tun_socket != NULL) {
soclose(V_udp6_tun_socket);
V_udp6_tun_socket = NULL;
}
#endif
}
static int
tcp_over_udp_start(void)
{
uint16_t port;
int ret;
#ifdef INET
struct sockaddr_in sin;
#endif
#ifdef INET6
struct sockaddr_in6 sin6;
#endif
sx_assert(&tcpoudp_lock, SA_XLOCKED);
port = V_tcp_udp_tunneling_port;
if (ntohs(port) == 0) {
/* Must have a port set */
return (EINVAL);
}
#ifdef INET
if (V_udp4_tun_socket != NULL) {
/* Already running -- must stop first */
return (EALREADY);
}
#endif
#ifdef INET6
if (V_udp6_tun_socket != NULL) {
/* Already running -- must stop first */
return (EALREADY);
}
#endif
#ifdef INET
if ((ret = socreate(PF_INET, &V_udp4_tun_socket,
SOCK_DGRAM, IPPROTO_UDP,
curthread->td_ucred, curthread))) {
tcp_over_udp_stop();
return (ret);
}
/* Call the special UDP hook. */
if ((ret = udp_set_kernel_tunneling(V_udp4_tun_socket,
tcp_recv_udp_tunneled_packet,
tcp_ctlinput_viaudp,
NULL))) {
tcp_over_udp_stop();
return (ret);
}
/* Ok, we have a socket, bind it to the port. */
memset(&sin, 0, sizeof(struct sockaddr_in));
sin.sin_len = sizeof(struct sockaddr_in);
sin.sin_family = AF_INET;
sin.sin_port = htons(port);
if ((ret = sobind(V_udp4_tun_socket,
(struct sockaddr *)&sin, curthread))) {
tcp_over_udp_stop();
return (ret);
}
#endif
#ifdef INET6
if ((ret = socreate(PF_INET6, &V_udp6_tun_socket,
SOCK_DGRAM, IPPROTO_UDP,
curthread->td_ucred, curthread))) {
tcp_over_udp_stop();
return (ret);
}
/* Call the special UDP hook. */
if ((ret = udp_set_kernel_tunneling(V_udp6_tun_socket,
tcp_recv_udp_tunneled_packet,
tcp6_ctlinput_viaudp,
NULL))) {
tcp_over_udp_stop();
return (ret);
}
/* Ok, we have a socket, bind it to the port. */
memset(&sin6, 0, sizeof(struct sockaddr_in6));
sin6.sin6_len = sizeof(struct sockaddr_in6);
sin6.sin6_family = AF_INET6;
sin6.sin6_port = htons(port);
if ((ret = sobind(V_udp6_tun_socket,
(struct sockaddr *)&sin6, curthread))) {
tcp_over_udp_stop();
return (ret);
}
#endif
return (0);
}
static int
sysctl_net_inet_tcp_udp_tunneling_port_check(SYSCTL_HANDLER_ARGS)
{
int error;
uint32_t old, new;
old = V_tcp_udp_tunneling_port;
new = old;
error = sysctl_handle_int(oidp, &new, 0, req);
if ((error == 0) &&
(req->newptr != NULL)) {
if ((new < TCP_TUNNELING_PORT_MIN) ||
(new > TCP_TUNNELING_PORT_MAX)) {
error = EINVAL;
} else {
sx_xlock(&tcpoudp_lock);
V_tcp_udp_tunneling_port = new;
if (old != 0) {
tcp_over_udp_stop();
}
if (new != 0) {
error = tcp_over_udp_start();
if (error != 0) {
V_tcp_udp_tunneling_port = 0;
}
}
sx_xunlock(&tcpoudp_lock);
}
}
return (error);
}
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_port,
CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
&VNET_NAME(tcp_udp_tunneling_port),
0, &sysctl_net_inet_tcp_udp_tunneling_port_check, "IU",
"Tunneling port for tcp over udp");
VNET_DEFINE(int, tcp_udp_tunneling_overhead) = TCP_TUNNELING_OVERHEAD_DEFAULT;
static int
sysctl_net_inet_tcp_udp_tunneling_overhead_check(SYSCTL_HANDLER_ARGS)
{
int error, new;
new = V_tcp_udp_tunneling_overhead;
error = sysctl_handle_int(oidp, &new, 0, req);
if (error == 0 && req->newptr) {
if ((new < TCP_TUNNELING_OVERHEAD_MIN) ||
(new > TCP_TUNNELING_OVERHEAD_MAX))
error = EINVAL;
else
V_tcp_udp_tunneling_overhead = new;
}
return (error);
}
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_overhead,
CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
&VNET_NAME(tcp_udp_tunneling_overhead),
0, &sysctl_net_inet_tcp_udp_tunneling_overhead_check, "IU",
"MSS reduction when using tcp over udp");
/*
* Exports one (struct tcp_function_info) for each alias/name.
*/
static int
sysctl_net_inet_list_func_info(SYSCTL_HANDLER_ARGS)
{
int cnt, error;
struct tcp_function *f;
struct tcp_function_info tfi;
/*
* We don't allow writes.
*/
if (req->newptr != NULL)
return (EINVAL);
/*
* Wire the old buffer so we can directly copy the functions to
* user space without dropping the lock.
*/
if (req->oldptr != NULL) {
error = sysctl_wire_old_buffer(req, 0);
if (error)
return (error);
}
/*
* Walk the list and copy out matching entries. If INVARIANTS
* is compiled in, also walk the list to verify the length of
* the list matches what we have recorded.
*/
rw_rlock(&tcp_function_lock);
cnt = 0;
#ifndef INVARIANTS
if (req->oldptr == NULL) {
cnt = tcp_fb_cnt;
goto skip_loop;
}
#endif
TAILQ_FOREACH(f, &t_functions, tf_next) {
#ifdef INVARIANTS
cnt++;
#endif
if (req->oldptr != NULL) {
bzero(&tfi, sizeof(tfi));
tfi.tfi_refcnt = f->tf_fb->tfb_refcnt;
tfi.tfi_id = f->tf_fb->tfb_id;
(void)strlcpy(tfi.tfi_alias, f->tf_name,
sizeof(tfi.tfi_alias));
(void)strlcpy(tfi.tfi_name,
f->tf_fb->tfb_tcp_block_name, sizeof(tfi.tfi_name));
error = SYSCTL_OUT(req, &tfi, sizeof(tfi));
/*
* Don't stop on error, as that is the
* mechanism we use to accumulate length
* information if the buffer was too short.
*/
}
}
KASSERT(cnt == tcp_fb_cnt,
("%s: cnt (%d) != tcp_fb_cnt (%d)", __func__, cnt, tcp_fb_cnt));
#ifndef INVARIANTS
skip_loop:
#endif
rw_runlock(&tcp_function_lock);
if (req->oldptr == NULL)
error = SYSCTL_OUT(req, NULL,
(cnt + 1) * sizeof(struct tcp_function_info));
return (error);
}
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, function_info,
CTLTYPE_OPAQUE | CTLFLAG_SKIP | CTLFLAG_RD | CTLFLAG_MPSAFE,
NULL, 0, sysctl_net_inet_list_func_info, "S,tcp_function_info",
"List TCP function block name-to-ID mappings");
/*
* tfb_tcp_handoff_ok() function for the default stack.
* Note that we'll basically try to take all comers.
*/
static int
tcp_default_handoff_ok(struct tcpcb *tp)
{
return (0);
}
/*
* tfb_tcp_fb_init() function for the default stack.
*
* This handles making sure we have appropriate timers set if you are
* transitioning a socket that has some amount of setup done.
*
* The init() fuction from the default can *never* return non-zero i.e.
* it is required to always succeed since it is the stack of last resort!
*/
static int
tcp_default_fb_init(struct tcpcb *tp, void **ptr)
{
struct socket *so = tptosocket(tp);
int rexmt;
INP_WLOCK_ASSERT(tptoinpcb(tp));
/* We don't use the pointer */
*ptr = NULL;
KASSERT(tp->t_state < TCPS_TIME_WAIT,
("%s: connection %p in unexpected state %d", __func__, tp,
tp->t_state));
/* Make sure we get no interesting mbuf queuing behavior */
/* All mbuf queue/ack compress flags should be off */
tcp_lro_features_off(tp);
/* Cancel the GP measurement in progress */
tp->t_flags &= ~TF_GPUTINPROG;
/* Validate the timers are not in usec, if they are convert */
tcp_change_time_units(tp, TCP_TMR_GRANULARITY_TICKS);
if ((tp->t_state == TCPS_SYN_SENT) ||
(tp->t_state == TCPS_SYN_RECEIVED))
rexmt = tcp_rexmit_initial * tcp_backoff[tp->t_rxtshift];
else
rexmt = TCP_REXMTVAL(tp) * tcp_backoff[tp->t_rxtshift];
if (tp->t_rxtshift == 0)
tp->t_rxtcur = rexmt;
else
TCPT_RANGESET(tp->t_rxtcur, rexmt, tp->t_rttmin, TCPTV_REXMTMAX);
/*
* Nothing to do for ESTABLISHED or LISTEN states. And, we don't
* know what to do for unexpected states (which includes TIME_WAIT).
*/
if (tp->t_state <= TCPS_LISTEN || tp->t_state >= TCPS_TIME_WAIT)
return (0);
/*
* Make sure some kind of transmission timer is set if there is
* outstanding data.
*/
if ((!TCPS_HAVEESTABLISHED(tp->t_state) || sbavail(&so->so_snd) ||
tp->snd_una != tp->snd_max) && !(tcp_timer_active(tp, TT_REXMT) ||
tcp_timer_active(tp, TT_PERSIST))) {
/*
* If the session has established and it looks like it should
* be in the persist state, set the persist timer. Otherwise,
* set the retransmit timer.
*/
if (TCPS_HAVEESTABLISHED(tp->t_state) && tp->snd_wnd == 0 &&
(int32_t)(tp->snd_nxt - tp->snd_una) <
(int32_t)sbavail(&so->so_snd))
tcp_setpersist(tp);
else
tcp_timer_activate(tp, TT_REXMT, TP_RXTCUR(tp));
}
/* All non-embryonic sessions get a keepalive timer. */
if (!tcp_timer_active(tp, TT_KEEP))
tcp_timer_activate(tp, TT_KEEP,
TCPS_HAVEESTABLISHED(tp->t_state) ? TP_KEEPIDLE(tp) :
TP_KEEPINIT(tp));
/*
* Make sure critical variables are initialized
* if transitioning while in Recovery.
*/
if IN_FASTRECOVERY(tp->t_flags) {
if (tp->sackhint.recover_fs == 0)
tp->sackhint.recover_fs = max(1,
tp->snd_nxt - tp->snd_una);
}
return (0);
}
/*
* tfb_tcp_fb_fini() function for the default stack.
*
* This changes state as necessary (or prudent) to prepare for another stack
* to assume responsibility for the connection.
*/
static void
tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged)
{
INP_WLOCK_ASSERT(tptoinpcb(tp));
#ifdef TCP_BLACKBOX
tcp_log_flowend(tp);
#endif
tp->t_acktime = 0;
return;
}
MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers");
MALLOC_DEFINE(M_TCPFUNCTIONS, "tcpfunc", "TCP function set memory");
static struct mtx isn_mtx;
#define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF)
#define ISN_LOCK() mtx_lock(&isn_mtx)
#define ISN_UNLOCK() mtx_unlock(&isn_mtx)
INPCBSTORAGE_DEFINE(tcpcbstor, tcpcb, "tcpinp", "tcp_inpcb", "tcp", "tcphash");
/*
* Take a value and get the next power of 2 that doesn't overflow.
* Used to size the tcp_inpcb hash buckets.
*/
static int
maketcp_hashsize(int size)
{
int hashsize;
/*
* auto tune.
* get the next power of 2 higher than maxsockets.
*/
hashsize = 1 << fls(size);
/* catch overflow, and just go one power of 2 smaller */
if (hashsize < size) {
hashsize = 1 << (fls(size) - 1);
}
return (hashsize);
}
static volatile int next_tcp_stack_id = 1;
/*
* Register a TCP function block with the name provided in the names
* array. (Note that this function does NOT automatically register
* blk->tfb_tcp_block_name as a stack name. Therefore, you should
* explicitly include blk->tfb_tcp_block_name in the list of names if
* you wish to register the stack with that name.)
*
* Either all name registrations will succeed or all will fail. If
* a name registration fails, the function will update the num_names
* argument to point to the array index of the name that encountered
* the failure.
*
* Returns 0 on success, or an error code on failure.
*/
int
register_tcp_functions_as_names(struct tcp_function_block *blk, int wait,
const char *names[], int *num_names)
{
struct tcp_function *f[TCP_FUNCTION_NAME_NUM_MAX];
struct tcp_function_set fs;
int error, i, num_registered;
KASSERT(names != NULL, ("%s: Called with NULL name list", __func__));
KASSERT(*num_names > 0,
("%s: Called with non-positive length of name list", __func__));
KASSERT(rw_initialized(&tcp_function_lock),
("%s: called too early", __func__));
if (*num_names > TCP_FUNCTION_NAME_NUM_MAX) {
/* Too many names. */
*num_names = 0;
return (E2BIG);
}
if ((blk->tfb_tcp_output == NULL) ||
(blk->tfb_tcp_do_segment == NULL) ||
(blk->tfb_tcp_ctloutput == NULL) ||
(blk->tfb_tcp_handoff_ok == NULL) ||
(strlen(blk->tfb_tcp_block_name) == 0)) {
/* These functions are required and a name is needed. */
*num_names = 0;
return (EINVAL);
}
for (i = 0; i < *num_names; i++) {
f[i] = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait);
if (f[i] == NULL) {
while (--i >= 0)
free(f[i], M_TCPFUNCTIONS);
*num_names = 0;
return (ENOMEM);
}
}
num_registered = 0;
rw_wlock(&tcp_function_lock);
if (find_tcp_fb_locked(blk, NULL) != NULL) {
/* A TCP function block can only be registered once. */
error = EALREADY;
goto cleanup;
}
if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) {
error = EINVAL;
goto cleanup;
}
refcount_init(&blk->tfb_refcnt, 0);
blk->tfb_id = atomic_fetchadd_int(&next_tcp_stack_id, 1);
for (i = 0; i < *num_names; i++) {
(void)strlcpy(fs.function_set_name, names[i],
sizeof(fs.function_set_name));
if (find_tcp_functions_locked(&fs) != NULL) {
/* Duplicate name space not allowed */
error = EALREADY;
goto cleanup;
}
f[i]->tf_fb = blk;
(void)strlcpy(f[i]->tf_name, names[i], sizeof(f[i]->tf_name));
TAILQ_INSERT_TAIL(&t_functions, f[i], tf_next);
tcp_fb_cnt++;
num_registered++;
}
rw_wunlock(&tcp_function_lock);
return (0);
cleanup:
/* Remove the entries just added. */
for (i = 0; i < *num_names; i++) {
if (i < num_registered) {
TAILQ_REMOVE(&t_functions, f[i], tf_next);
tcp_fb_cnt--;
}
f[i]->tf_fb = NULL;
free(f[i], M_TCPFUNCTIONS);
}
rw_wunlock(&tcp_function_lock);
*num_names = num_registered;
return (error);
}
/*
* Register a TCP function block using the name provided in the name
* argument.
*
* Returns 0 on success, or an error code on failure.
*/
int
register_tcp_functions_as_name(struct tcp_function_block *blk, const char *name,
int wait)
{
const char *name_list[1];
int num_names, rv;
num_names = 1;
if (name != NULL)
name_list[0] = name;
else
name_list[0] = blk->tfb_tcp_block_name;
rv = register_tcp_functions_as_names(blk, wait, name_list, &num_names);
return (rv);
}
/*
* Register a TCP function block using the name defined in
* blk->tfb_tcp_block_name.
*
* Returns 0 on success, or an error code on failure.
*/
int
register_tcp_functions(struct tcp_function_block *blk, int wait)
{
return (register_tcp_functions_as_name(blk, NULL, wait));
}
/*
* Deregister all names associated with a function block. This
* functionally removes the function block from use within the system.
*
* When called with a true quiesce argument, mark the function block
* as being removed so no more stacks will use it and determine
* whether the removal would succeed.
*
* When called with a false quiesce argument, actually attempt the
* removal.
*
* When called with a force argument, attempt to switch all TCBs to
* use the default stack instead of returning EBUSY.
*
* Returns 0 on success (or if the removal would succeed), or an error
* code on failure.
*/
int
deregister_tcp_functions(struct tcp_function_block *blk, bool quiesce,
bool force)
{
struct tcp_function *f;
VNET_ITERATOR_DECL(vnet_iter);
if (blk == &tcp_def_funcblk) {
/* You can't un-register the default */
return (EPERM);
}
rw_wlock(&tcp_function_lock);
VNET_LIST_RLOCK_NOSLEEP();
VNET_FOREACH(vnet_iter) {
CURVNET_SET(vnet_iter);
if (blk == V_tcp_func_set_ptr) {
/* You can't free the current default in some vnet. */
CURVNET_RESTORE();
VNET_LIST_RUNLOCK_NOSLEEP();
rw_wunlock(&tcp_function_lock);
return (EBUSY);
}
CURVNET_RESTORE();
}
VNET_LIST_RUNLOCK_NOSLEEP();
/* Mark the block so no more stacks can use it. */
blk->tfb_flags |= TCP_FUNC_BEING_REMOVED;
/*
* If TCBs are still attached to the stack, attempt to switch them
* to the default stack.
*/
if (force && blk->tfb_refcnt) {
struct inpcb *inp;
struct tcpcb *tp;
VNET_ITERATOR_DECL(vnet_iter);
rw_wunlock(&tcp_function_lock);
VNET_LIST_RLOCK();
VNET_FOREACH(vnet_iter) {
CURVNET_SET(vnet_iter);
struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo,
INPLOOKUP_WLOCKPCB);
while ((inp = inp_next(&inpi)) != NULL) {
tp = intotcpcb(inp);
if (tp == NULL || tp->t_fb != blk)
continue;
tcp_switch_back_to_default(tp);
}
CURVNET_RESTORE();
}
VNET_LIST_RUNLOCK();
rw_wlock(&tcp_function_lock);
}
if (blk->tfb_refcnt) {
/* TCBs still attached. */
rw_wunlock(&tcp_function_lock);
return (EBUSY);
}
if (quiesce) {
/* Skip removal. */
rw_wunlock(&tcp_function_lock);
return (0);
}
/* Remove any function names that map to this function block. */
while (find_tcp_fb_locked(blk, &f) != NULL) {
TAILQ_REMOVE(&t_functions, f, tf_next);
tcp_fb_cnt--;
f->tf_fb = NULL;
free(f, M_TCPFUNCTIONS);
}
rw_wunlock(&tcp_function_lock);
return (0);
}
static void
tcp_drain(void)
{
struct epoch_tracker et;
VNET_ITERATOR_DECL(vnet_iter);
if (!do_tcpdrain)
return;
NET_EPOCH_ENTER(et);
VNET_LIST_RLOCK_NOSLEEP();
VNET_FOREACH(vnet_iter) {
CURVNET_SET(vnet_iter);
struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo,
INPLOOKUP_WLOCKPCB);
struct inpcb *inpb;
struct tcpcb *tcpb;
/*
* Walk the tcpbs, if existing, and flush the reassembly queue,
* if there is one...
* XXX: The "Net/3" implementation doesn't imply that the TCP
* reassembly queue should be flushed, but in a situation
* where we're really low on mbufs, this is potentially
* useful.
*/
while ((inpb = inp_next(&inpi)) != NULL) {
if ((tcpb = intotcpcb(inpb)) != NULL) {
tcp_reass_flush(tcpb);
tcp_clean_sackreport(tcpb);
#ifdef TCP_BLACKBOX
tcp_log_drain(tcpb);
#endif
#ifdef TCPPCAP
if (tcp_pcap_aggressive_free) {
/* Free the TCP PCAP queues. */
tcp_pcap_drain(&(tcpb->t_inpkts));
tcp_pcap_drain(&(tcpb->t_outpkts));
}
#endif
}
}
CURVNET_RESTORE();
}
VNET_LIST_RUNLOCK_NOSLEEP();
NET_EPOCH_EXIT(et);
}
static void
tcp_vnet_init(void *arg __unused)
{
#ifdef TCP_HHOOK
if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN,
&V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0)
printf("%s: WARNING: unable to register helper hook\n", __func__);
if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT,
&V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0)
printf("%s: WARNING: unable to register helper hook\n", __func__);
#endif
#ifdef STATS
if (tcp_stats_init())
printf("%s: WARNING: unable to initialise TCP stats\n",
__func__);
#endif
in_pcbinfo_init(&V_tcbinfo, &tcpcbstor, tcp_tcbhashsize,
tcp_tcbhashsize);
syncache_init();
tcp_hc_init();
TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack);
V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole),
NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
tcp_fastopen_init();
COUNTER_ARRAY_ALLOC(V_tcps_states, TCP_NSTATES, M_WAITOK);
VNET_PCPUSTAT_ALLOC(tcpstat, M_WAITOK);
V_tcp_msl = TCPTV_MSL;
arc4rand(&V_ts_offset_secret, sizeof(V_ts_offset_secret), 0);
}
VNET_SYSINIT(tcp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
tcp_vnet_init, NULL);
static void
tcp_init(void *arg __unused)
{
int hashsize;
tcp_reass_global_init();
/* XXX virtualize those below? */
tcp_delacktime = TCPTV_DELACK;
tcp_keepinit = TCPTV_KEEP_INIT;
tcp_keepidle = TCPTV_KEEP_IDLE;
tcp_keepintvl = TCPTV_KEEPINTVL;
tcp_maxpersistidle = TCPTV_KEEP_IDLE;
tcp_rexmit_initial = TCPTV_RTOBASE;
if (tcp_rexmit_initial < 1)
tcp_rexmit_initial = 1;
tcp_rexmit_min = TCPTV_MIN;
if (tcp_rexmit_min < 1)
tcp_rexmit_min = 1;
tcp_persmin = TCPTV_PERSMIN;
tcp_persmax = TCPTV_PERSMAX;
tcp_rexmit_slop = TCPTV_CPU_VAR;
tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT;
/* Setup the tcp function block list */
TAILQ_INIT(&t_functions);
rw_init(&tcp_function_lock, "tcp_func_lock");
register_tcp_functions(&tcp_def_funcblk, M_WAITOK);
sx_init(&tcpoudp_lock, "TCP over UDP configuration");
#ifdef TCP_BLACKBOX
/* Initialize the TCP logging data. */
tcp_log_init();
#endif
if (tcp_soreceive_stream) {
#ifdef INET
tcp_protosw.pr_soreceive = soreceive_stream;
#endif
#ifdef INET6
tcp6_protosw.pr_soreceive = soreceive_stream;
#endif /* INET6 */
}
#ifdef INET6
max_protohdr_grow(sizeof(struct ip6_hdr) + sizeof(struct tcphdr));
#else /* INET6 */
max_protohdr_grow(sizeof(struct tcpiphdr));
#endif /* INET6 */
ISN_LOCK_INIT();
EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL,
SHUTDOWN_PRI_DEFAULT);
EVENTHANDLER_REGISTER(vm_lowmem, tcp_drain, NULL, LOWMEM_PRI_DEFAULT);
EVENTHANDLER_REGISTER(mbuf_lowmem, tcp_drain, NULL, LOWMEM_PRI_DEFAULT);
tcp_inp_lro_direct_queue = counter_u64_alloc(M_WAITOK);
tcp_inp_lro_wokeup_queue = counter_u64_alloc(M_WAITOK);
tcp_inp_lro_compressed = counter_u64_alloc(M_WAITOK);
tcp_inp_lro_locks_taken = counter_u64_alloc(M_WAITOK);
tcp_extra_mbuf = counter_u64_alloc(M_WAITOK);
tcp_would_have_but = counter_u64_alloc(M_WAITOK);
tcp_comp_total = counter_u64_alloc(M_WAITOK);
tcp_uncomp_total = counter_u64_alloc(M_WAITOK);
tcp_bad_csums = counter_u64_alloc(M_WAITOK);
tcp_pacing_failures = counter_u64_alloc(M_WAITOK);
tcp_dgp_failures = counter_u64_alloc(M_WAITOK);
#ifdef TCPPCAP
tcp_pcap_init();
#endif
hashsize = tcp_tcbhashsize;
if (hashsize == 0) {
/*
* Auto tune the hash size based on maxsockets.
* A perfect hash would have a 1:1 mapping
* (hashsize = maxsockets) however it's been
* suggested that O(2) average is better.
*/
hashsize = maketcp_hashsize(maxsockets / 4);
/*
* Our historical default is 512,
* do not autotune lower than this.
*/
if (hashsize < 512)
hashsize = 512;
if (bootverbose)
printf("%s: %s auto tuned to %d\n", __func__,
"net.inet.tcp.tcbhashsize", hashsize);
}
/*
* We require a hashsize to be a power of two.
* Previously if it was not a power of two we would just reset it
* back to 512, which could be a nasty surprise if you did not notice
* the error message.
* Instead what we do is clip it to the closest power of two lower
* than the specified hash value.
*/
if (!powerof2(hashsize)) {
int oldhashsize = hashsize;
hashsize = maketcp_hashsize(hashsize);
/* prevent absurdly low value */
if (hashsize < 16)
hashsize = 16;
printf("%s: WARNING: TCB hash size not a power of 2, "
"clipped from %d to %d.\n", __func__, oldhashsize,
hashsize);
}
tcp_tcbhashsize = hashsize;
#ifdef INET
IPPROTO_REGISTER(IPPROTO_TCP, tcp_input, tcp_ctlinput);
#endif
#ifdef INET6
IP6PROTO_REGISTER(IPPROTO_TCP, tcp6_input, tcp6_ctlinput);
#endif
}
SYSINIT(tcp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, tcp_init, NULL);
#ifdef VIMAGE
static void
tcp_destroy(void *unused __unused)
{
#ifdef TCP_HHOOK
int error;
#endif
tcp_hc_destroy();
syncache_destroy();
in_pcbinfo_destroy(&V_tcbinfo);
/* tcp_discardcb() clears the sack_holes up. */
uma_zdestroy(V_sack_hole_zone);
/*
* Cannot free the zone until all tcpcbs are released as we attach
* the allocations to them.
*/
tcp_fastopen_destroy();
COUNTER_ARRAY_FREE(V_tcps_states, TCP_NSTATES);
VNET_PCPUSTAT_FREE(tcpstat);
#ifdef TCP_HHOOK
error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]);
if (error != 0) {
printf("%s: WARNING: unable to deregister helper hook "
"type=%d, id=%d: error %d returned\n", __func__,
HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error);
}
error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]);
if (error != 0) {
printf("%s: WARNING: unable to deregister helper hook "
"type=%d, id=%d: error %d returned\n", __func__,
HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error);
}
#endif
}
VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL);
#endif
void
tcp_fini(void *xtp)
{
}
/*
* Fill in the IP and TCP headers for an outgoing packet, given the tcpcb.
* tcp_template used to store this data in mbufs, but we now recopy it out
* of the tcpcb each time to conserve mbufs.
*/
void
tcpip_fillheaders(struct inpcb *inp, uint16_t port, void *ip_ptr, void *tcp_ptr)
{
struct tcphdr *th = (struct tcphdr *)tcp_ptr;
INP_WLOCK_ASSERT(inp);
#ifdef INET6
if ((inp->inp_vflag & INP_IPV6) != 0) {
struct ip6_hdr *ip6;
ip6 = (struct ip6_hdr *)ip_ptr;
ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) |
(inp->inp_flow & IPV6_FLOWINFO_MASK);
ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) |
(IPV6_VERSION & IPV6_VERSION_MASK);
if (port == 0)
ip6->ip6_nxt = IPPROTO_TCP;
else
ip6->ip6_nxt = IPPROTO_UDP;
ip6->ip6_plen = htons(sizeof(struct tcphdr));
ip6->ip6_src = inp->in6p_laddr;
ip6->ip6_dst = inp->in6p_faddr;
}
#endif /* INET6 */
#if defined(INET6) && defined(INET)
else
#endif
#ifdef INET
{
struct ip *ip;
ip = (struct ip *)ip_ptr;
ip->ip_v = IPVERSION;
ip->ip_hl = 5;
ip->ip_tos = inp->inp_ip_tos;
ip->ip_len = 0;
ip->ip_id = 0;
ip->ip_off = 0;
ip->ip_ttl = inp->inp_ip_ttl;
ip->ip_sum = 0;
if (port == 0)
ip->ip_p = IPPROTO_TCP;
else
ip->ip_p = IPPROTO_UDP;
ip->ip_src = inp->inp_laddr;
ip->ip_dst = inp->inp_faddr;
}
#endif /* INET */
th->th_sport = inp->inp_lport;
th->th_dport = inp->inp_fport;
th->th_seq = 0;
th->th_ack = 0;
th->th_off = 5;
tcp_set_flags(th, 0);
th->th_win = 0;
th->th_urp = 0;
th->th_sum = 0; /* in_pseudo() is called later for ipv4 */
}
/*
* Create template to be used to send tcp packets on a connection.
* Allocates an mbuf and fills in a skeletal tcp/ip header. The only
* use for this function is in keepalives, which use tcp_respond.
*/
struct tcptemp *
tcpip_maketemplate(struct inpcb *inp)
{
struct tcptemp *t;
t = malloc(sizeof(*t), M_TEMP, M_NOWAIT);
if (t == NULL)
return (NULL);
tcpip_fillheaders(inp, 0, (void *)&t->tt_ipgen, (void *)&t->tt_t);
return (t);
}
/*
* Send a single message to the TCP at address specified by
* the given TCP/IP header. If m == NULL, then we make a copy
* of the tcpiphdr at th and send directly to the addressed host.
* This is used to force keep alive messages out using the TCP
* template for a connection. If flags are given then we send
* a message back to the TCP which originated the segment th,
* and discard the mbuf containing it and any other attached mbufs.
*
* In any case the ack and sequence number of the transmitted
* segment are as specified by the parameters.
*
* NOTE: If m != NULL, then th must point to *inside* the mbuf.
*/
void
tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m,
tcp_seq ack, tcp_seq seq, uint16_t flags)
{
struct tcpopt to;
struct inpcb *inp;
struct ip *ip;
struct mbuf *optm;
struct udphdr *uh = NULL;
struct tcphdr *nth;
struct tcp_log_buffer *lgb;
u_char *optp;
#ifdef INET6
struct ip6_hdr *ip6;
int isipv6;
#endif /* INET6 */
int optlen, tlen, win, ulen;
int ect = 0;
bool incl_opts;
uint16_t port;
int output_ret;
#ifdef INVARIANTS
int thflags = tcp_get_flags(th);
#endif
KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL"));
NET_EPOCH_ASSERT();
#ifdef INET6
isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4);
ip6 = ipgen;
#endif /* INET6 */
ip = ipgen;
if (tp != NULL) {
inp = tptoinpcb(tp);
INP_LOCK_ASSERT(inp);
} else
inp = NULL;
if (m != NULL) {
#ifdef INET6
if (isipv6 && ip6 && (ip6->ip6_nxt == IPPROTO_UDP))
port = m->m_pkthdr.tcp_tun_port;
else
#endif
if (ip && (ip->ip_p == IPPROTO_UDP))
port = m->m_pkthdr.tcp_tun_port;
else
port = 0;
} else
port = tp->t_port;
incl_opts = false;
win = 0;
if (tp != NULL) {
if (!(flags & TH_RST)) {
win = sbspace(&inp->inp_socket->so_rcv);
if (win > TCP_MAXWIN << tp->rcv_scale)
win = TCP_MAXWIN << tp->rcv_scale;
}
if ((tp->t_flags & TF_NOOPT) == 0)
incl_opts = true;
}
if (m == NULL) {
m = m_gethdr(M_NOWAIT, MT_DATA);
if (m == NULL)
return;
m->m_data += max_linkhdr;
#ifdef INET6
if (isipv6) {
bcopy((caddr_t)ip6, mtod(m, caddr_t),
sizeof(struct ip6_hdr));
ip6 = mtod(m, struct ip6_hdr *);
nth = (struct tcphdr *)(ip6 + 1);
if (port) {
/* Insert a UDP header */
uh = (struct udphdr *)nth;
uh->uh_sport = htons(V_tcp_udp_tunneling_port);
uh->uh_dport = port;
nth = (struct tcphdr *)(uh + 1);
}
} else
#endif /* INET6 */
{
bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip));
ip = mtod(m, struct ip *);
nth = (struct tcphdr *)(ip + 1);
if (port) {
/* Insert a UDP header */
uh = (struct udphdr *)nth;
uh->uh_sport = htons(V_tcp_udp_tunneling_port);
uh->uh_dport = port;
nth = (struct tcphdr *)(uh + 1);
}
}
bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr));
flags = TH_ACK;
} else if ((!M_WRITABLE(m)) || (port != 0)) {
struct mbuf *n;
/* Can't reuse 'm', allocate a new mbuf. */
n = m_gethdr(M_NOWAIT, MT_DATA);
if (n == NULL) {
m_freem(m);
return;
}
if (!m_dup_pkthdr(n, m, M_NOWAIT)) {
m_freem(m);
m_freem(n);
return;
}
n->m_data += max_linkhdr;
/* m_len is set later */
#define xchg(a,b,type) { type t; t=a; a=b; b=t; }
#ifdef INET6
if (isipv6) {
bcopy((caddr_t)ip6, mtod(n, caddr_t),
sizeof(struct ip6_hdr));
ip6 = mtod(n, struct ip6_hdr *);
xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr);
nth = (struct tcphdr *)(ip6 + 1);
if (port) {
/* Insert a UDP header */
uh = (struct udphdr *)nth;
uh->uh_sport = htons(V_tcp_udp_tunneling_port);
uh->uh_dport = port;
nth = (struct tcphdr *)(uh + 1);
}
} else
#endif /* INET6 */
{
bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip));
ip = mtod(n, struct ip *);
xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t);
nth = (struct tcphdr *)(ip + 1);
if (port) {
/* Insert a UDP header */
uh = (struct udphdr *)nth;
uh->uh_sport = htons(V_tcp_udp_tunneling_port);
uh->uh_dport = port;
nth = (struct tcphdr *)(uh + 1);
}
}
bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr));
xchg(nth->th_dport, nth->th_sport, uint16_t);
th = nth;
m_freem(m);
m = n;
} else {
/*
* reuse the mbuf.
* XXX MRT We inherit the FIB, which is lucky.
*/
m_freem(m->m_next);
m->m_next = NULL;
m->m_data = (caddr_t)ipgen;
/* clear any receive flags for proper bpf timestamping */
m->m_flags &= ~(M_TSTMP | M_TSTMP_LRO);
/* m_len is set later */
#ifdef INET6
if (isipv6) {
xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr);
nth = (struct tcphdr *)(ip6 + 1);
} else
#endif /* INET6 */
{
xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t);
nth = (struct tcphdr *)(ip + 1);
}
if (th != nth) {
/*
* this is usually a case when an extension header
* exists between the IPv6 header and the
* TCP header.
*/
nth->th_sport = th->th_sport;
nth->th_dport = th->th_dport;
}
xchg(nth->th_dport, nth->th_sport, uint16_t);
#undef xchg
}
tlen = 0;
#ifdef INET6
if (isipv6)
tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr);
#endif
#if defined(INET) && defined(INET6)
else
#endif
#ifdef INET
tlen = sizeof (struct tcpiphdr);
#endif
if (port)
tlen += sizeof (struct udphdr);
#ifdef INVARIANTS
m->m_len = 0;
KASSERT(M_TRAILINGSPACE(m) >= tlen,
("Not enough trailing space for message (m=%p, need=%d, have=%ld)",
m, tlen, (long)M_TRAILINGSPACE(m)));
#endif
m->m_len = tlen;
to.to_flags = 0;
if (incl_opts) {
ect = tcp_ecn_output_established(tp, &flags, 0, false);
/* Make sure we have room. */
if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) {
m->m_next = m_get(M_NOWAIT, MT_DATA);
if (m->m_next) {
optp = mtod(m->m_next, u_char *);
optm = m->m_next;
} else
incl_opts = false;
} else {
optp = (u_char *) (nth + 1);
optm = m;
}
}
if (incl_opts) {
/* Timestamps. */
if (tp->t_flags & TF_RCVD_TSTMP) {
to.to_tsval = tcp_ts_getticks() + tp->ts_offset;
to.to_tsecr = tp->ts_recent;
to.to_flags |= TOF_TS;
}
#if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
/* TCP-MD5 (RFC2385). */
if (tp->t_flags & TF_SIGNATURE)
to.to_flags |= TOF_SIGNATURE;
#endif
/* Add the options. */
tlen += optlen = tcp_addoptions(&to, optp);
/* Update m_len in the correct mbuf. */
optm->m_len += optlen;
} else
optlen = 0;
#ifdef INET6
if (isipv6) {
if (uh) {
ulen = tlen - sizeof(struct ip6_hdr);
uh->uh_ulen = htons(ulen);
}
ip6->ip6_flow = htonl(ect << IPV6_FLOWLABEL_LEN);
ip6->ip6_vfc = IPV6_VERSION;
if (port)
ip6->ip6_nxt = IPPROTO_UDP;
else
ip6->ip6_nxt = IPPROTO_TCP;
ip6->ip6_plen = htons(tlen - sizeof(*ip6));
}
#endif
#if defined(INET) && defined(INET6)
else
#endif
#ifdef INET
{
if (uh) {
ulen = tlen - sizeof(struct ip);
uh->uh_ulen = htons(ulen);
}
ip->ip_len = htons(tlen);
if (inp != NULL) {
ip->ip_tos = inp->inp_ip_tos & ~IPTOS_ECN_MASK;
ip->ip_ttl = inp->inp_ip_ttl;
} else {
ip->ip_tos = 0;
ip->ip_ttl = V_ip_defttl;
}
ip->ip_tos |= ect;
if (port) {
ip->ip_p = IPPROTO_UDP;
} else {
ip->ip_p = IPPROTO_TCP;
}
if (V_path_mtu_discovery)
ip->ip_off |= htons(IP_DF);
}
#endif
m->m_pkthdr.len = tlen;
m->m_pkthdr.rcvif = NULL;
#ifdef MAC
if (inp != NULL) {
/*
* Packet is associated with a socket, so allow the
* label of the response to reflect the socket label.
*/
INP_LOCK_ASSERT(inp);
mac_inpcb_create_mbuf(inp, m);
} else {
/*
* Packet is not associated with a socket, so possibly
* update the label in place.
*/
mac_netinet_tcp_reply(m);
}
#endif
nth->th_seq = htonl(seq);
nth->th_ack = htonl(ack);
nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2;
tcp_set_flags(nth, flags);
if (tp && (flags & TH_RST)) {
/* Log the reset */
tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST);
}
if (tp != NULL)
nth->th_win = htons((u_short) (win >> tp->rcv_scale));
else
nth->th_win = htons((u_short)win);
nth->th_urp = 0;
#if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
if (to.to_flags & TOF_SIGNATURE) {
if (!TCPMD5_ENABLED() ||
TCPMD5_OUTPUT(m, nth, to.to_signature) != 0) {
m_freem(m);
return;
}
}
#endif
#ifdef INET6
if (isipv6) {
if (port) {
m->m_pkthdr.csum_flags = CSUM_UDP_IPV6;
m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
uh->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0);
nth->th_sum = 0;
} else {
m->m_pkthdr.csum_flags = CSUM_TCP_IPV6;
m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
nth->th_sum = in6_cksum_pseudo(ip6,
tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0);
}
ip6->ip6_hlim = in6_selecthlim(inp, NULL);
}
#endif /* INET6 */
#if defined(INET6) && defined(INET)
else
#endif
#ifdef INET
{
if (port) {
uh->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
htons(ulen + IPPROTO_UDP));
m->m_pkthdr.csum_flags = CSUM_UDP;
m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
nth->th_sum = 0;
} else {
m->m_pkthdr.csum_flags = CSUM_TCP;
m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p)));
}
}
#endif /* INET */
TCP_PROBE3(debug__output, tp, th, m);
if (flags & TH_RST)
TCP_PROBE5(accept__refused, NULL, NULL, m, tp, nth);
lgb = NULL;
if ((tp != NULL) && tcp_bblogging_on(tp)) {
if (INP_WLOCKED(inp)) {
union tcp_log_stackspecific log;
struct timeval tv;
memset(&log.u_bbr, 0, sizeof(log.u_bbr));
log.u_bbr.inhpts = tcp_in_hpts(tp);
log.u_bbr.flex8 = 4;
log.u_bbr.pkts_out = tp->t_maxseg;
log.u_bbr.timeStamp = tcp_get_usecs(&tv);
log.u_bbr.delivered = 0;
lgb = tcp_log_event(tp, nth, NULL, NULL, TCP_LOG_OUT,
ERRNO_UNK, 0, &log, false, NULL, NULL, 0, &tv);
} else {
/*
* We can not log the packet, since we only own the
* read lock, but a write lock is needed. The read lock
* is not upgraded to a write lock, since only getting
* the read lock was done intentionally to improve the
* handling of SYN flooding attacks.
* This happens only for pure SYN segments received in
* the initial CLOSED state, or received in a more
* advanced state than listen and the UDP encapsulation
* port is unexpected.
* The incoming SYN segments do not really belong to
* the TCP connection and the handling does not change
* the state of the TCP connection. Therefore, the
* sending of the RST segments is not logged. Please
* note that also the incoming SYN segments are not
* logged.
*
* The following code ensures that the above description
* is and stays correct.
*/
KASSERT((thflags & (TH_ACK|TH_SYN)) == TH_SYN &&
(tp->t_state == TCPS_CLOSED ||
(tp->t_state > TCPS_LISTEN && tp->t_port != port)),
("%s: Logging of TCP segment with flags 0x%b and "
"UDP encapsulation port %u skipped in state %s",
__func__, thflags, PRINT_TH_FLAGS,
ntohs(port), tcpstates[tp->t_state]));
}
}
if (flags & TH_ACK)
TCPSTAT_INC(tcps_sndacks);
else if (flags & (TH_SYN|TH_FIN|TH_RST))
TCPSTAT_INC(tcps_sndctrl);
TCPSTAT_INC(tcps_sndtotal);
#ifdef INET6
if (isipv6) {
TCP_PROBE5(send, NULL, tp, ip6, tp, nth);
output_ret = ip6_output(m, inp ? inp->in6p_outputopts : NULL,
NULL, 0, NULL, NULL, inp);
}
#endif /* INET6 */
#if defined(INET) && defined(INET6)
else
#endif
#ifdef INET
{
TCP_PROBE5(send, NULL, tp, ip, tp, nth);
output_ret = ip_output(m, NULL, NULL, 0, NULL, inp);
}
#endif
if (lgb != NULL)
lgb->tlb_errno = output_ret;
}
/*
* Send a challenge ack (no data, no SACK option), but not more than
* V_tcp_ack_war_cnt per V_tcp_ack_war_time_window (per TCP connection).
*/
void
tcp_send_challenge_ack(struct tcpcb *tp, struct tcphdr *th, struct mbuf *m)
{
sbintime_t now;
bool send_challenge_ack;
if (V_tcp_ack_war_time_window == 0 || V_tcp_ack_war_cnt == 0) {
/* ACK war protection is disabled. */
send_challenge_ack = true;
} else {
/* Start new epoch, if the previous one is already over. */
now = getsbinuptime();
if (tp->t_challenge_ack_end < now) {
tp->t_challenge_ack_cnt = 0;
tp->t_challenge_ack_end = now +
V_tcp_ack_war_time_window * SBT_1MS;
}
/*
* Send a challenge ACK, if less than tcp_ack_war_cnt have been
* sent in the current epoch.
*/
if (tp->t_challenge_ack_cnt < V_tcp_ack_war_cnt) {
send_challenge_ack = true;
tp->t_challenge_ack_cnt++;
} else {
send_challenge_ack = false;
}
}
if (send_challenge_ack) {
tcp_respond(tp, mtod(m, void *), th, m, tp->rcv_nxt,
tp->snd_nxt, TH_ACK);
tp->last_ack_sent = tp->rcv_nxt;
}
}
/*
* Create a new TCP control block, making an empty reassembly queue and hooking
* it to the argument protocol control block. The `inp' parameter must have
* come from the zone allocator set up by tcpcbstor declaration.
* The caller can provide a pointer to a tcpcb of the listener to inherit the
* TCP function block from the listener.
*/
struct tcpcb *
tcp_newtcpcb(struct inpcb *inp, struct tcpcb *listening_tcb)
{
struct tcpcb *tp = intotcpcb(inp);
#ifdef INET6
int isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
#endif /* INET6 */
/*
* Historically allocation was done with M_ZERO. There is a lot of
* code that rely on that. For now take safe approach and zero whole
* tcpcb. This definitely can be optimized.
*/
bzero(&tp->t_start_zero, t_zero_size);
/* Initialise cc_var struct for this tcpcb. */
tp->t_ccv.tp = tp;
rw_rlock(&tcp_function_lock);
if (listening_tcb != NULL) {
INP_LOCK_ASSERT(tptoinpcb(listening_tcb));
KASSERT(listening_tcb->t_fb != NULL,
("tcp_newtcpcb: listening_tcb->t_fb is NULL"));
if (listening_tcb->t_fb->tfb_flags & TCP_FUNC_BEING_REMOVED) {
rw_runlock(&tcp_function_lock);
return (NULL);
}
tp->t_fb = listening_tcb->t_fb;
} else {
tp->t_fb = V_tcp_func_set_ptr;
}
refcount_acquire(&tp->t_fb->tfb_refcnt);
KASSERT((tp->t_fb->tfb_flags & TCP_FUNC_BEING_REMOVED) == 0,
("tcp_newtcpcb: using TFB being removed"));
rw_runlock(&tcp_function_lock);
CC_LIST_RLOCK();
if (listening_tcb != NULL) {
if (CC_ALGO(listening_tcb)->flags & CC_MODULE_BEING_REMOVED) {
CC_LIST_RUNLOCK();
if (tp->t_fb->tfb_tcp_fb_fini)
(*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
refcount_release(&tp->t_fb->tfb_refcnt);
return (NULL);
}
CC_ALGO(tp) = CC_ALGO(listening_tcb);
} else
CC_ALGO(tp) = CC_DEFAULT_ALGO();
cc_refer(CC_ALGO(tp));
CC_LIST_RUNLOCK();
if (CC_ALGO(tp)->cb_init != NULL)
if (CC_ALGO(tp)->cb_init(&tp->t_ccv, NULL) > 0) {
cc_detach(tp);
if (tp->t_fb->tfb_tcp_fb_fini)
(*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
refcount_release(&tp->t_fb->tfb_refcnt);
return (NULL);
}
#ifdef TCP_HHOOK
if (khelp_init_osd(HELPER_CLASS_TCP, &tp->t_osd)) {
if (CC_ALGO(tp)->cb_destroy != NULL)
CC_ALGO(tp)->cb_destroy(&tp->t_ccv);
CC_DATA(tp) = NULL;
cc_detach(tp);
if (tp->t_fb->tfb_tcp_fb_fini)
(*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
refcount_release(&tp->t_fb->tfb_refcnt);
return (NULL);
}
#endif
TAILQ_INIT(&tp->t_segq);
STAILQ_INIT(&tp->t_inqueue);
tp->t_maxseg =
#ifdef INET6
isipv6 ? V_tcp_v6mssdflt :
#endif /* INET6 */
V_tcp_mssdflt;
/* All mbuf queue/ack compress flags should be off */
tcp_lro_features_off(tp);
tp->t_hpts_cpu = HPTS_CPU_NONE;
tp->t_lro_cpu = HPTS_CPU_NONE;
callout_init_rw(&tp->t_callout, &inp->inp_lock,
CALLOUT_TRYLOCK | CALLOUT_RETURNUNLOCKED);
for (int i = 0; i < TT_N; i++)
tp->t_timers[i] = SBT_MAX;
switch (V_tcp_do_rfc1323) {
case 0:
break;
default:
case 1:
tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP);
break;
case 2:
tp->t_flags = TF_REQ_SCALE;
break;
case 3:
tp->t_flags = TF_REQ_TSTMP;
break;
}
if (V_tcp_do_sack)
tp->t_flags |= TF_SACK_PERMIT;
TAILQ_INIT(&tp->snd_holes);
/*
* Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no
* rtt estimate. Set rttvar so that srtt + 4 * rttvar gives
* reasonable initial retransmit time.
*/
tp->t_srtt = TCPTV_SRTTBASE;
tp->t_rttvar = ((tcp_rexmit_initial - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4;
tp->t_rttmin = tcp_rexmit_min;
tp->t_rxtcur = tcp_rexmit_initial;
tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT;
tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT;
tp->t_rcvtime = ticks;
/* We always start with ticks granularity */
tp->t_tmr_granularity = TCP_TMR_GRANULARITY_TICKS;
/*
* IPv4 TTL initialization is necessary for an IPv6 socket as well,
* because the socket may be bound to an IPv6 wildcard address,
* which may match an IPv4-mapped IPv6 address.
*/
inp->inp_ip_ttl = V_ip_defttl;
#ifdef TCPPCAP
/*
* Init the TCP PCAP queues.
*/
tcp_pcap_tcpcb_init(tp);
#endif
#ifdef TCP_BLACKBOX
/* Initialize the per-TCPCB log data. */
tcp_log_tcpcbinit(tp);
#endif
tp->t_pacing_rate = -1;
if (tp->t_fb->tfb_tcp_fb_init) {
if ((*tp->t_fb->tfb_tcp_fb_init)(tp, &tp->t_fb_ptr)) {
if (CC_ALGO(tp)->cb_destroy != NULL)
CC_ALGO(tp)->cb_destroy(&tp->t_ccv);
CC_DATA(tp) = NULL;
cc_detach(tp);
#ifdef TCP_HHOOK
khelp_destroy_osd(&tp->t_osd);
#endif
refcount_release(&tp->t_fb->tfb_refcnt);
return (NULL);
}
}
#ifdef STATS
if (V_tcp_perconn_stats_enable == 1)
tp->t_stats = stats_blob_alloc(V_tcp_perconn_stats_dflt_tpl, 0);
#endif
if (V_tcp_do_lrd)
tp->t_flags |= TF_LRD;
return (tp);
}
/*
* Drop a TCP connection, reporting
* the specified error. If connection is synchronized,
* then send a RST to peer.
*/
struct tcpcb *
tcp_drop(struct tcpcb *tp, int errno)
{
struct socket *so = tptosocket(tp);
NET_EPOCH_ASSERT();
INP_WLOCK_ASSERT(tptoinpcb(tp));
if (TCPS_HAVERCVDSYN(tp->t_state)) {
tcp_state_change(tp, TCPS_CLOSED);
/* Don't use tcp_output() here due to possible recursion. */
(void)tcp_output_nodrop(tp);
TCPSTAT_INC(tcps_drops);
} else
TCPSTAT_INC(tcps_conndrops);
if (errno == ETIMEDOUT && tp->t_softerror)
errno = tp->t_softerror;
so->so_error = errno;
return (tcp_close(tp));
}
void
tcp_discardcb(struct tcpcb *tp)
{
struct inpcb *inp = tptoinpcb(tp);
struct socket *so = tptosocket(tp);
struct mbuf *m;
#ifdef INET6
bool isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
#endif
INP_WLOCK_ASSERT(inp);
MPASS(!callout_active(&tp->t_callout));
MPASS(TAILQ_EMPTY(&tp->snd_holes));
/* free the reassembly queue, if any */
tcp_reass_flush(tp);
#ifdef TCP_OFFLOAD
/* Disconnect offload device, if any. */
if (tp->t_flags & TF_TOE)
tcp_offload_detach(tp);
#endif
#ifdef TCPPCAP
/* Free the TCP PCAP queues. */
tcp_pcap_drain(&(tp->t_inpkts));
tcp_pcap_drain(&(tp->t_outpkts));
#endif
/* Allow the CC algorithm to clean up after itself. */
if (CC_ALGO(tp)->cb_destroy != NULL)
CC_ALGO(tp)->cb_destroy(&tp->t_ccv);
CC_DATA(tp) = NULL;
/* Detach from the CC algorithm */
cc_detach(tp);
#ifdef TCP_HHOOK
khelp_destroy_osd(&tp->t_osd);
#endif
#ifdef STATS
stats_blob_destroy(tp->t_stats);
#endif
CC_ALGO(tp) = NULL;
if ((m = STAILQ_FIRST(&tp->t_inqueue)) != NULL) {
struct mbuf *prev;
STAILQ_INIT(&tp->t_inqueue);
STAILQ_FOREACH_FROM_SAFE(m, &tp->t_inqueue, m_stailqpkt, prev)
m_freem(m);
}
TCPSTATES_DEC(tp->t_state);
if (tp->t_fb->tfb_tcp_fb_fini)
(*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
MPASS(!tcp_in_hpts(tp));
#ifdef TCP_BLACKBOX
tcp_log_tcpcbfini(tp);
#endif
/*
* If we got enough samples through the srtt filter,
* save the rtt and rttvar in the routing entry.
* 'Enough' is arbitrarily defined as 4 rtt samples.
* 4 samples is enough for the srtt filter to converge
* to within enough % of the correct value; fewer samples
* and we could save a bogus rtt. The danger is not high
* as tcp quickly recovers from everything.
* XXX: Works very well but needs some more statistics!
*
* XXXRRS: Updating must be after the stack fini() since
* that may be converting some internal representation of
* say srtt etc into the general one used by other stacks.
* Lets also at least protect against the so being NULL
* as RW stated below.
*/
if ((tp->t_rttupdated >= 4) && (so != NULL)) {
struct hc_metrics_lite metrics;
uint32_t ssthresh;
bzero(&metrics, sizeof(metrics));
/*
* Update the ssthresh always when the conditions below
* are satisfied. This gives us better new start value
* for the congestion avoidance for new connections.
* ssthresh is only set if packet loss occurred on a session.
*
* XXXRW: 'so' may be NULL here, and/or socket buffer may be
* being torn down. Ideally this code would not use 'so'.
*/
ssthresh = tp->snd_ssthresh;
if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) {
/*
* convert the limit from user data bytes to
* packets then to packet data bytes.
*/
ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg;
if (ssthresh < 2)
ssthresh = 2;
ssthresh *= (tp->t_maxseg +
#ifdef INET6
(isipv6 ? sizeof (struct ip6_hdr) +
sizeof (struct tcphdr) :
#endif
sizeof (struct tcpiphdr)
#ifdef INET6
)
#endif
);
} else
ssthresh = 0;
metrics.rmx_ssthresh = ssthresh;
metrics.rmx_rtt = tp->t_srtt;
metrics.rmx_rttvar = tp->t_rttvar;
metrics.rmx_cwnd = tp->snd_cwnd;
metrics.rmx_sendpipe = 0;
metrics.rmx_recvpipe = 0;
tcp_hc_update(&inp->inp_inc, &metrics);
}
refcount_release(&tp->t_fb->tfb_refcnt);
}
/*
* Attempt to close a TCP control block, marking it as dropped, and freeing
* the socket if we hold the only reference.
*/
struct tcpcb *
tcp_close(struct tcpcb *tp)
{
struct inpcb *inp = tptoinpcb(tp);
struct socket *so = tptosocket(tp);
INP_WLOCK_ASSERT(inp);
#ifdef TCP_OFFLOAD
if (tp->t_state == TCPS_LISTEN)
tcp_offload_listen_stop(tp);
#endif
/*
* This releases the TFO pending counter resource for TFO listen
* sockets as well as passively-created TFO sockets that transition
* from SYN_RECEIVED to CLOSED.
*/
if (tp->t_tfo_pending) {
tcp_fastopen_decrement_counter(tp->t_tfo_pending);
tp->t_tfo_pending = NULL;
}
tcp_timer_stop(tp);
if (tp->t_fb->tfb_tcp_timer_stop_all != NULL)
tp->t_fb->tfb_tcp_timer_stop_all(tp);
in_pcbdrop(inp);
TCPSTAT_INC(tcps_closed);
if (tp->t_state != TCPS_CLOSED)
tcp_state_change(tp, TCPS_CLOSED);
KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL"));
tcp_free_sackholes(tp);
soisdisconnected(so);
if (inp->inp_flags & INP_SOCKREF) {
inp->inp_flags &= ~INP_SOCKREF;
INP_WUNLOCK(inp);
sorele(so);
return (NULL);
}
return (tp);
}
/*
* Notify a tcp user of an asynchronous error;
* store error as soft error, but wake up user
* (for now, won't do anything until can select for soft error).
*
* Do not wake up user since there currently is no mechanism for
* reporting soft errors (yet - a kqueue filter may be added).
*/
static struct inpcb *
tcp_notify(struct inpcb *inp, int error)
{
struct tcpcb *tp;
INP_WLOCK_ASSERT(inp);
tp = intotcpcb(inp);
KASSERT(tp != NULL, ("tcp_notify: tp == NULL"));
/*
* Ignore some errors if we are hooked up.
* If connection hasn't completed, has retransmitted several times,
* and receives a second error, give up now. This is better
* than waiting a long time to establish a connection that
* can never complete.
*/
if (tp->t_state == TCPS_ESTABLISHED &&
(error == EHOSTUNREACH || error == ENETUNREACH ||
error == EHOSTDOWN)) {
if (inp->inp_route.ro_nh) {
NH_FREE(inp->inp_route.ro_nh);
inp->inp_route.ro_nh = (struct nhop_object *)NULL;
}
return (inp);
} else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 &&
tp->t_softerror) {
tp = tcp_drop(tp, error);
if (tp != NULL)
return (inp);
else
return (NULL);
} else {
tp->t_softerror = error;
return (inp);
}
#if 0
wakeup( &so->so_timeo);
sorwakeup(so);
sowwakeup(so);
#endif
}
static int
tcp_pcblist(SYSCTL_HANDLER_ARGS)
{
struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo,
INPLOOKUP_RLOCKPCB);
struct xinpgen xig;
struct inpcb *inp;
int error;
if (req->newptr != NULL)
return (EPERM);
if (req->oldptr == NULL) {
int n;
n = V_tcbinfo.ipi_count +
counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]);
n += imax(n / 8, 10);
req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb);
return (0);
}
if ((error = sysctl_wire_old_buffer(req, 0)) != 0)
return (error);
bzero(&xig, sizeof(xig));
xig.xig_len = sizeof xig;
xig.xig_count = V_tcbinfo.ipi_count +
counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]);
xig.xig_gen = V_tcbinfo.ipi_gencnt;
xig.xig_sogen = so_gencnt;
error = SYSCTL_OUT(req, &xig, sizeof xig);
if (error)
return (error);
error = syncache_pcblist(req);
if (error)
return (error);
while ((inp = inp_next(&inpi)) != NULL) {
if (inp->inp_gencnt <= xig.xig_gen &&
cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
struct xtcpcb xt;
tcp_inptoxtp(inp, &xt);
error = SYSCTL_OUT(req, &xt, sizeof xt);
if (error) {
INP_RUNLOCK(inp);
break;
} else
continue;
}
}
if (!error) {
/*
* Give the user an updated idea of our state.
* If the generation differs from what we told
* her before, she knows that something happened
* while we were processing this request, and it
* might be necessary to retry.
*/
xig.xig_gen = V_tcbinfo.ipi_gencnt;
xig.xig_sogen = so_gencnt;
xig.xig_count = V_tcbinfo.ipi_count +
counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]);
error = SYSCTL_OUT(req, &xig, sizeof xig);
}
return (error);
}
SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist,
CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
NULL, 0, tcp_pcblist, "S,xtcpcb",
"List of active TCP connections");
#ifdef INET
static int
tcp_getcred(SYSCTL_HANDLER_ARGS)
{
struct xucred xuc;
struct sockaddr_in addrs[2];
struct epoch_tracker et;
struct inpcb *inp;
int error;
error = priv_check(req->td, PRIV_NETINET_GETCRED);
if (error)
return (error);
error = SYSCTL_IN(req, addrs, sizeof(addrs));
if (error)
return (error);
NET_EPOCH_ENTER(et);
inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port,
addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL);
NET_EPOCH_EXIT(et);
if (inp != NULL) {
if (error == 0)
error = cr_canseeinpcb(req->td->td_ucred, inp);
if (error == 0)
cru2x(inp->inp_cred, &xuc);
INP_RUNLOCK(inp);
} else
error = ENOENT;
if (error == 0)
error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
return (error);
}
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred,
CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT,
0, 0, tcp_getcred, "S,xucred",
"Get the xucred of a TCP connection");
#endif /* INET */
#ifdef INET6
static int
tcp6_getcred(SYSCTL_HANDLER_ARGS)
{
struct epoch_tracker et;
struct xucred xuc;
struct sockaddr_in6 addrs[2];
struct inpcb *inp;
int error;
#ifdef INET
int mapped = 0;
#endif
error = priv_check(req->td, PRIV_NETINET_GETCRED);
if (error)
return (error);
error = SYSCTL_IN(req, addrs, sizeof(addrs));
if (error)
return (error);
if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 ||
(error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) {
return (error);
}
if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) {
#ifdef INET
if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr))
mapped = 1;
else
#endif
return (EINVAL);
}
NET_EPOCH_ENTER(et);
#ifdef INET
if (mapped == 1)
inp = in_pcblookup(&V_tcbinfo,
*(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12],
addrs[1].sin6_port,
*(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12],
addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL);
else
#endif
inp = in6_pcblookup(&V_tcbinfo,
&addrs[1].sin6_addr, addrs[1].sin6_port,
&addrs[0].sin6_addr, addrs[0].sin6_port,
INPLOOKUP_RLOCKPCB, NULL);
NET_EPOCH_EXIT(et);
if (inp != NULL) {
if (error == 0)
error = cr_canseeinpcb(req->td->td_ucred, inp);
if (error == 0)
cru2x(inp->inp_cred, &xuc);
INP_RUNLOCK(inp);
} else
error = ENOENT;
if (error == 0)
error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
return (error);
}
SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred,
CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT,
0, 0, tcp6_getcred, "S,xucred",
"Get the xucred of a TCP6 connection");
#endif /* INET6 */
#ifdef INET
/* Path MTU to try next when a fragmentation-needed message is received. */
static inline int
tcp_next_pmtu(const struct icmp *icp, const struct ip *ip)
{
int mtu = ntohs(icp->icmp_nextmtu);
/* If no alternative MTU was proposed, try the next smaller one. */
if (!mtu)
mtu = ip_next_mtu(ntohs(ip->ip_len), 1);
if (mtu < V_tcp_minmss + sizeof(struct tcpiphdr))
mtu = V_tcp_minmss + sizeof(struct tcpiphdr);
return (mtu);
}
static void
tcp_ctlinput_with_port(struct icmp *icp, uint16_t port)
{
struct ip *ip;
struct tcphdr *th;
struct inpcb *inp;
struct tcpcb *tp;
struct inpcb *(*notify)(struct inpcb *, int);
struct in_conninfo inc;
tcp_seq icmp_tcp_seq;
int errno, mtu;
errno = icmp_errmap(icp);
switch (errno) {
case 0:
return;
case EMSGSIZE:
notify = tcp_mtudisc_notify;
break;
case ECONNREFUSED:
if (V_icmp_may_rst)
notify = tcp_drop_syn_sent;
else
notify = tcp_notify;
break;
case EHOSTUNREACH:
if (V_icmp_may_rst && icp->icmp_type == ICMP_TIMXCEED)
notify = tcp_drop_syn_sent;
else
notify = tcp_notify;
break;
default:
notify = tcp_notify;
}
ip = &icp->icmp_ip;
th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2));
icmp_tcp_seq = th->th_seq;
inp = in_pcblookup(&V_tcbinfo, ip->ip_dst, th->th_dport, ip->ip_src,
th->th_sport, INPLOOKUP_WLOCKPCB, NULL);
if (inp != NULL) {
tp = intotcpcb(inp);
#ifdef TCP_OFFLOAD
if (tp->t_flags & TF_TOE && errno == EMSGSIZE) {
/*
* MTU discovery for offloaded connections. Let
* the TOE driver verify seq# and process it.
*/
mtu = tcp_next_pmtu(icp, ip);
tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu);
goto out;
}
#endif
if (tp->t_port != port)
goto out;
if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) &&
SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) {
if (errno == EMSGSIZE) {
/*
* MTU discovery: we got a needfrag and
* will potentially try a lower MTU.
*/
mtu = tcp_next_pmtu(icp, ip);
/*
* Only process the offered MTU if it
* is smaller than the current one.
*/
if (mtu < tp->t_maxseg +
sizeof(struct tcpiphdr)) {
bzero(&inc, sizeof(inc));
inc.inc_faddr = ip->ip_dst;
inc.inc_fibnum =
inp->inp_inc.inc_fibnum;
tcp_hc_updatemtu(&inc, mtu);
inp = tcp_mtudisc(inp, mtu);
}
} else
inp = (*notify)(inp, errno);
}
} else {
bzero(&inc, sizeof(inc));
inc.inc_fport = th->th_dport;
inc.inc_lport = th->th_sport;
inc.inc_faddr = ip->ip_dst;
inc.inc_laddr = ip->ip_src;
syncache_unreach(&inc, icmp_tcp_seq, port);
}
out:
if (inp != NULL)
INP_WUNLOCK(inp);
}
static void
tcp_ctlinput(struct icmp *icmp)
{
tcp_ctlinput_with_port(icmp, htons(0));
}
static void
tcp_ctlinput_viaudp(udp_tun_icmp_param_t param)
{
/* Its a tunneled TCP over UDP icmp */
struct icmp *icmp = param.icmp;
struct ip *outer_ip, *inner_ip;
struct udphdr *udp;
struct tcphdr *th, ttemp;
int i_hlen, o_len;
uint16_t port;
outer_ip = (struct ip *)((caddr_t)icmp - sizeof(struct ip));
inner_ip = &icmp->icmp_ip;
i_hlen = inner_ip->ip_hl << 2;
o_len = ntohs(outer_ip->ip_len);
if (o_len <
(sizeof(struct ip) + 8 + i_hlen + sizeof(struct udphdr) + offsetof(struct tcphdr, th_ack))) {
/* Not enough data present */
return;
}
/* Ok lets strip out the inner udphdr header by copying up on top of it the tcp hdr */
udp = (struct udphdr *)(((caddr_t)inner_ip) + i_hlen);
if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) {
return;
}
port = udp->uh_dport;
th = (struct tcphdr *)(udp + 1);
memcpy(&ttemp, th, sizeof(struct tcphdr));
memcpy(udp, &ttemp, sizeof(struct tcphdr));
/* Now adjust down the size of the outer IP header */
o_len -= sizeof(struct udphdr);
outer_ip->ip_len = htons(o_len);
/* Now call in to the normal handling code */
tcp_ctlinput_with_port(icmp, port);
}
#endif /* INET */
#ifdef INET6
static inline int
tcp6_next_pmtu(const struct icmp6_hdr *icmp6)
{
int mtu = ntohl(icmp6->icmp6_mtu);
/*
* If no alternative MTU was proposed, or the proposed MTU was too
* small, set to the min.
*/
if (mtu < IPV6_MMTU)
mtu = IPV6_MMTU - 8; /* XXXNP: what is the adjustment for? */
return (mtu);
}
static void
tcp6_ctlinput_with_port(struct ip6ctlparam *ip6cp, uint16_t port)
{
struct in6_addr *dst;
struct inpcb *(*notify)(struct inpcb *, int);
struct ip6_hdr *ip6;
struct mbuf *m;
struct inpcb *inp;
struct tcpcb *tp;
struct icmp6_hdr *icmp6;
struct in_conninfo inc;
struct tcp_ports {
uint16_t th_sport;
uint16_t th_dport;
} t_ports;
tcp_seq icmp_tcp_seq;
unsigned int mtu;
unsigned int off;
int errno;
icmp6 = ip6cp->ip6c_icmp6;
m = ip6cp->ip6c_m;
ip6 = ip6cp->ip6c_ip6;
off = ip6cp->ip6c_off;
dst = &ip6cp->ip6c_finaldst->sin6_addr;
errno = icmp6_errmap(icmp6);
switch (errno) {
case 0:
return;
case EMSGSIZE:
notify = tcp_mtudisc_notify;
break;
case ECONNREFUSED:
if (V_icmp_may_rst)
notify = tcp_drop_syn_sent;
else
notify = tcp_notify;
break;
case EHOSTUNREACH:
/*
* There are only four ICMPs that may reset connection:
* - administratively prohibited
* - port unreachable
* - time exceeded in transit
* - unknown next header
*/
if (V_icmp_may_rst &&
((icmp6->icmp6_type == ICMP6_DST_UNREACH &&
(icmp6->icmp6_code == ICMP6_DST_UNREACH_ADMIN ||
icmp6->icmp6_code == ICMP6_DST_UNREACH_NOPORT)) ||
(icmp6->icmp6_type == ICMP6_TIME_EXCEEDED &&
icmp6->icmp6_code == ICMP6_TIME_EXCEED_TRANSIT) ||
(icmp6->icmp6_type == ICMP6_PARAM_PROB &&
icmp6->icmp6_code == ICMP6_PARAMPROB_NEXTHEADER)))
notify = tcp_drop_syn_sent;
else
notify = tcp_notify;
break;
default:
notify = tcp_notify;
}
/* Check if we can safely get the ports from the tcp hdr */
if (m == NULL ||
(m->m_pkthdr.len <
(int32_t) (off + sizeof(struct tcp_ports)))) {
return;
}
bzero(&t_ports, sizeof(struct tcp_ports));
m_copydata(m, off, sizeof(struct tcp_ports), (caddr_t)&t_ports);
inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, t_ports.th_dport,
&ip6->ip6_src, t_ports.th_sport, INPLOOKUP_WLOCKPCB, NULL);
off += sizeof(struct tcp_ports);
if (m->m_pkthdr.len < (int32_t) (off + sizeof(tcp_seq))) {
goto out;
}
m_copydata(m, off, sizeof(tcp_seq), (caddr_t)&icmp_tcp_seq);
if (inp != NULL) {
tp = intotcpcb(inp);
#ifdef TCP_OFFLOAD
if (tp->t_flags & TF_TOE && errno == EMSGSIZE) {
/* MTU discovery for offloaded connections. */
mtu = tcp6_next_pmtu(icmp6);
tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu);
goto out;
}
#endif
if (tp->t_port != port)
goto out;
if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) &&
SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) {
if (errno == EMSGSIZE) {
/*
* MTU discovery:
* If we got a needfrag set the MTU
* in the route to the suggested new
* value (if given) and then notify.
*/
mtu = tcp6_next_pmtu(icmp6);
bzero(&inc, sizeof(inc));
inc.inc_fibnum = M_GETFIB(m);
inc.inc_flags |= INC_ISIPV6;
inc.inc6_faddr = *dst;
if (in6_setscope(&inc.inc6_faddr,
m->m_pkthdr.rcvif, NULL))
goto out;
/*
* Only process the offered MTU if it
* is smaller than the current one.
*/
if (mtu < tp->t_maxseg +
sizeof (struct tcphdr) +
sizeof (struct ip6_hdr)) {
tcp_hc_updatemtu(&inc, mtu);
tcp_mtudisc(inp, mtu);
ICMP6STAT_INC(icp6s_pmtuchg);
}
} else
inp = (*notify)(inp, errno);
}
} else {
bzero(&inc, sizeof(inc));
inc.inc_fibnum = M_GETFIB(m);
inc.inc_flags |= INC_ISIPV6;
inc.inc_fport = t_ports.th_dport;
inc.inc_lport = t_ports.th_sport;
inc.inc6_faddr = *dst;
inc.inc6_laddr = ip6->ip6_src;
syncache_unreach(&inc, icmp_tcp_seq, port);
}
out:
if (inp != NULL)
INP_WUNLOCK(inp);
}
static void
tcp6_ctlinput(struct ip6ctlparam *ctl)
{
tcp6_ctlinput_with_port(ctl, htons(0));
}
static void
tcp6_ctlinput_viaudp(udp_tun_icmp_param_t param)
{
struct ip6ctlparam *ip6cp = param.ip6cp;
struct mbuf *m;
struct udphdr *udp;
uint16_t port;
m = m_pulldown(ip6cp->ip6c_m, ip6cp->ip6c_off, sizeof(struct udphdr), NULL);
if (m == NULL) {
return;
}
udp = mtod(m, struct udphdr *);
if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) {
return;
}
port = udp->uh_dport;
m_adj(m, sizeof(struct udphdr));
if ((m->m_flags & M_PKTHDR) == 0) {
ip6cp->ip6c_m->m_pkthdr.len -= sizeof(struct udphdr);
}
/* Now call in to the normal handling code */
tcp6_ctlinput_with_port(ip6cp, port);
}
#endif /* INET6 */
static uint32_t
tcp_keyed_hash(struct in_conninfo *inc, u_char *key, u_int len)
{
SIPHASH_CTX ctx;
uint32_t hash[2];
KASSERT(len >= SIPHASH_KEY_LENGTH,
("%s: keylen %u too short ", __func__, len));
SipHash24_Init(&ctx);
SipHash_SetKey(&ctx, (uint8_t *)key);
SipHash_Update(&ctx, &inc->inc_fport, sizeof(uint16_t));
SipHash_Update(&ctx, &inc->inc_lport, sizeof(uint16_t));
switch (inc->inc_flags & INC_ISIPV6) {
#ifdef INET
case 0:
SipHash_Update(&ctx, &inc->inc_faddr, sizeof(struct in_addr));
SipHash_Update(&ctx, &inc->inc_laddr, sizeof(struct in_addr));
break;
#endif
#ifdef INET6
case INC_ISIPV6:
SipHash_Update(&ctx, &inc->inc6_faddr, sizeof(struct in6_addr));
SipHash_Update(&ctx, &inc->inc6_laddr, sizeof(struct in6_addr));
break;
#endif
}
SipHash_Final((uint8_t *)hash, &ctx);
return (hash[0] ^ hash[1]);
}
uint32_t
tcp_new_ts_offset(struct in_conninfo *inc)
{
struct in_conninfo inc_store, *local_inc;
if (!V_tcp_ts_offset_per_conn) {
memcpy(&inc_store, inc, sizeof(struct in_conninfo));
inc_store.inc_lport = 0;
inc_store.inc_fport = 0;
local_inc = &inc_store;
} else {
local_inc = inc;
}
return (tcp_keyed_hash(local_inc, V_ts_offset_secret,
sizeof(V_ts_offset_secret)));
}
/*
* Following is where TCP initial sequence number generation occurs.
*
* There are two places where we must use initial sequence numbers:
* 1. In SYN-ACK packets.
* 2. In SYN packets.
*
* All ISNs for SYN-ACK packets are generated by the syncache. See
* tcp_syncache.c for details.
*
* The ISNs in SYN packets must be monotonic; TIME_WAIT recycling
* depends on this property. In addition, these ISNs should be
* unguessable so as to prevent connection hijacking. To satisfy
* the requirements of this situation, the algorithm outlined in
* RFC 1948 is used, with only small modifications.
*
* Implementation details:
*
* Time is based off the system timer, and is corrected so that it
* increases by one megabyte per second. This allows for proper
* recycling on high speed LANs while still leaving over an hour
* before rollover.
*
* As reading the *exact* system time is too expensive to be done
* whenever setting up a TCP connection, we increment the time
* offset in two ways. First, a small random positive increment
* is added to isn_offset for each connection that is set up.
* Second, the function tcp_isn_tick fires once per clock tick
* and increments isn_offset as necessary so that sequence numbers
* are incremented at approximately ISN_BYTES_PER_SECOND. The
* random positive increments serve only to ensure that the same
* exact sequence number is never sent out twice (as could otherwise
* happen when a port is recycled in less than the system tick
* interval.)
*
* net.inet.tcp.isn_reseed_interval controls the number of seconds
* between seeding of isn_secret. This is normally set to zero,
* as reseeding should not be necessary.
*
* Locking of the global variables isn_secret, isn_last_reseed, isn_offset,
* isn_offset_old, and isn_ctx is performed using the ISN lock. In
* general, this means holding an exclusive (write) lock.
*/
#define ISN_BYTES_PER_SECOND 1048576
#define ISN_STATIC_INCREMENT 4096
#define ISN_RANDOM_INCREMENT (4096 - 1)
#define ISN_SECRET_LENGTH SIPHASH_KEY_LENGTH
VNET_DEFINE_STATIC(u_char, isn_secret[ISN_SECRET_LENGTH]);
VNET_DEFINE_STATIC(int, isn_last);
VNET_DEFINE_STATIC(int, isn_last_reseed);
VNET_DEFINE_STATIC(u_int32_t, isn_offset);
VNET_DEFINE_STATIC(u_int32_t, isn_offset_old);
#define V_isn_secret VNET(isn_secret)
#define V_isn_last VNET(isn_last)
#define V_isn_last_reseed VNET(isn_last_reseed)
#define V_isn_offset VNET(isn_offset)
#define V_isn_offset_old VNET(isn_offset_old)
tcp_seq
tcp_new_isn(struct in_conninfo *inc)
{
tcp_seq new_isn;
u_int32_t projected_offset;
ISN_LOCK();
/* Seed if this is the first use, reseed if requested. */
if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) &&
(((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz)
< (u_int)ticks))) {
arc4rand(&V_isn_secret, sizeof(V_isn_secret), 0);
V_isn_last_reseed = ticks;
}
/* Compute the hash and return the ISN. */
new_isn = (tcp_seq)tcp_keyed_hash(inc, V_isn_secret,
sizeof(V_isn_secret));
V_isn_offset += ISN_STATIC_INCREMENT +
(arc4random() & ISN_RANDOM_INCREMENT);
if (ticks != V_isn_last) {
projected_offset = V_isn_offset_old +
ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last);
if (SEQ_GT(projected_offset, V_isn_offset))
V_isn_offset = projected_offset;
V_isn_offset_old = V_isn_offset;
V_isn_last = ticks;
}
new_isn += V_isn_offset;
ISN_UNLOCK();
return (new_isn);
}
/*
* When a specific ICMP unreachable message is received and the
* connection state is SYN-SENT, drop the connection. This behavior
* is controlled by the icmp_may_rst sysctl.
*/
static struct inpcb *
tcp_drop_syn_sent(struct inpcb *inp, int errno)
{
struct tcpcb *tp;
NET_EPOCH_ASSERT();
INP_WLOCK_ASSERT(inp);
tp = intotcpcb(inp);
if (tp->t_state != TCPS_SYN_SENT)
return (inp);
if (tp->t_flags & TF_FASTOPEN)
tcp_fastopen_disable_path(tp);
tp = tcp_drop(tp, errno);
if (tp != NULL)
return (inp);
else
return (NULL);
}
/*
* When `need fragmentation' ICMP is received, update our idea of the MSS
* based on the new value. Also nudge TCP to send something, since we
* know the packet we just sent was dropped.
* This duplicates some code in the tcp_mss() function in tcp_input.c.
*/
static struct inpcb *
tcp_mtudisc_notify(struct inpcb *inp, int error)
{
return (tcp_mtudisc(inp, -1));
}
static struct inpcb *
tcp_mtudisc(struct inpcb *inp, int mtuoffer)
{
struct tcpcb *tp;
struct socket *so;
INP_WLOCK_ASSERT(inp);
tp = intotcpcb(inp);
KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL"));
tcp_mss_update(tp, -1, mtuoffer, NULL, NULL);
so = inp->inp_socket;
SOCK_SENDBUF_LOCK(so);
/* If the mss is larger than the socket buffer, decrease the mss. */
if (so->so_snd.sb_hiwat < tp->t_maxseg) {
tp->t_maxseg = so->so_snd.sb_hiwat;
if (tp->t_maxseg < V_tcp_mssdflt) {
/*
* The MSS is so small we should not process incoming
* SACK's since we are subject to attack in such a
* case.
*/
tp->t_flags2 |= TF2_PROC_SACK_PROHIBIT;
} else {
tp->t_flags2 &= ~TF2_PROC_SACK_PROHIBIT;
}
}
SOCK_SENDBUF_UNLOCK(so);
TCPSTAT_INC(tcps_mturesent);
tp->t_rtttime = 0;
tp->snd_nxt = tp->snd_una;
tcp_free_sackholes(tp);
tp->snd_recover = tp->snd_max;
if (tp->t_flags & TF_SACK_PERMIT)
EXIT_FASTRECOVERY(tp->t_flags);
if (tp->t_fb->tfb_tcp_mtu_chg != NULL) {
/*
* Conceptually the snd_nxt setting
* and freeing sack holes should
* be done by the default stacks
* own tfb_tcp_mtu_chg().
*/
tp->t_fb->tfb_tcp_mtu_chg(tp);
}
if (tcp_output(tp) < 0)
return (NULL);
else
return (inp);
}
#ifdef INET
/*
* Look-up the routing entry to the peer of this inpcb. If no route
* is found and it cannot be allocated, then return 0. This routine
* is called by TCP routines that access the rmx structure and by
* tcp_mss_update to get the peer/interface MTU.
*/
uint32_t
tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap)
{
struct nhop_object *nh;
struct ifnet *ifp;
uint32_t maxmtu = 0;
KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer"));
if (inc->inc_faddr.s_addr != INADDR_ANY) {
nh = fib4_lookup(inc->inc_fibnum, inc->inc_faddr, 0, NHR_NONE, 0);
if (nh == NULL)
return (0);
ifp = nh->nh_ifp;
maxmtu = nh->nh_mtu;
/* Report additional interface capabilities. */
if (cap != NULL) {
if (ifp->if_capenable & IFCAP_TSO4 &&
ifp->if_hwassist & CSUM_TSO) {
cap->ifcap |= CSUM_TSO;
cap->tsomax = ifp->if_hw_tsomax;
cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount;
cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize;
/* XXXKIB IFCAP2_IPSEC_OFFLOAD_TSO */
cap->ipsec_tso = (ifp->if_capenable2 &
IFCAP2_BIT(IFCAP2_IPSEC_OFFLOAD)) != 0;
}
}
}
return (maxmtu);
}
#endif /* INET */
#ifdef INET6
uint32_t
tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap)
{
struct nhop_object *nh;
struct in6_addr dst6;
uint32_t scopeid;
struct ifnet *ifp;
uint32_t maxmtu = 0;
KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer"));
if (inc->inc_flags & INC_IPV6MINMTU)
return (IPV6_MMTU);
if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) {
in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid);
nh = fib6_lookup(inc->inc_fibnum, &dst6, scopeid, NHR_NONE, 0);
if (nh == NULL)
return (0);
ifp = nh->nh_ifp;
maxmtu = nh->nh_mtu;
/* Report additional interface capabilities. */
if (cap != NULL) {
if (ifp->if_capenable & IFCAP_TSO6 &&
ifp->if_hwassist & CSUM_TSO) {
cap->ifcap |= CSUM_TSO;
cap->tsomax = ifp->if_hw_tsomax;
cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount;
cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize;
cap->ipsec_tso = false; /* XXXKIB */
}
}
}
return (maxmtu);
}
/*
* Handle setsockopt(IPV6_USE_MIN_MTU) by a TCP stack.
*
* XXXGL: we are updating inpcb here with INC_IPV6MINMTU flag.
* The right place to do that is ip6_setpktopt() that has just been
* executed. By the way it just filled ip6po_minmtu for us.
*/
void
tcp6_use_min_mtu(struct tcpcb *tp)
{
struct inpcb *inp = tptoinpcb(tp);
INP_WLOCK_ASSERT(inp);
/*
* In case of the IPV6_USE_MIN_MTU socket
* option, the INC_IPV6MINMTU flag to announce
* a corresponding MSS during the initial
* handshake. If the TCP connection is not in
* the front states, just reduce the MSS being
* used. This avoids the sending of TCP
* segments which will be fragmented at the
* IPv6 layer.
*/
inp->inp_inc.inc_flags |= INC_IPV6MINMTU;
if ((tp->t_state >= TCPS_SYN_SENT) &&
(inp->inp_inc.inc_flags & INC_ISIPV6)) {
struct ip6_pktopts *opt;
opt = inp->in6p_outputopts;
if (opt != NULL && opt->ip6po_minmtu == IP6PO_MINMTU_ALL &&
tp->t_maxseg > TCP6_MSS) {
tp->t_maxseg = TCP6_MSS;
if (tp->t_maxseg < V_tcp_mssdflt) {
/*
* The MSS is so small we should not process incoming
* SACK's since we are subject to attack in such a
* case.
*/
tp->t_flags2 |= TF2_PROC_SACK_PROHIBIT;
} else {
tp->t_flags2 &= ~TF2_PROC_SACK_PROHIBIT;
}
}
}
}
#endif /* INET6 */
/*
* Calculate effective SMSS per RFC5681 definition for a given TCP
* connection at its current state, taking into account SACK and etc.
*/
u_int
tcp_maxseg(const struct tcpcb *tp)
{
u_int optlen;
if (tp->t_flags & TF_NOOPT)
return (tp->t_maxseg);
/*
* Here we have a simplified code from tcp_addoptions(),
* without a proper loop, and having most of paddings hardcoded.
* We might make mistakes with padding here in some edge cases,
* but this is harmless, since result of tcp_maxseg() is used
* only in cwnd and ssthresh estimations.
*/
if (TCPS_HAVEESTABLISHED(tp->t_state)) {
if (tp->t_flags & TF_RCVD_TSTMP)
optlen = TCPOLEN_TSTAMP_APPA;
else
optlen = 0;
#if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
if (tp->t_flags & TF_SIGNATURE)
optlen += PADTCPOLEN(TCPOLEN_SIGNATURE);
#endif
if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) {
optlen += TCPOLEN_SACKHDR;
optlen += tp->rcv_numsacks * TCPOLEN_SACK;
optlen = PADTCPOLEN(optlen);
}
} else {
if (tp->t_flags & TF_REQ_TSTMP)
optlen = TCPOLEN_TSTAMP_APPA;
else
optlen = PADTCPOLEN(TCPOLEN_MAXSEG);
if (tp->t_flags & TF_REQ_SCALE)
optlen += PADTCPOLEN(TCPOLEN_WINDOW);
#if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
if (tp->t_flags & TF_SIGNATURE)
optlen += PADTCPOLEN(TCPOLEN_SIGNATURE);
#endif
if (tp->t_flags & TF_SACK_PERMIT)
optlen += PADTCPOLEN(TCPOLEN_SACK_PERMITTED);
}
optlen = min(optlen, TCP_MAXOLEN);
return (tp->t_maxseg - optlen);
}
u_int
tcp_fixed_maxseg(const struct tcpcb *tp)
{
int optlen;
if (tp->t_flags & TF_NOOPT)
return (tp->t_maxseg);
/*
* Here we have a simplified code from tcp_addoptions(),
* without a proper loop, and having most of paddings hardcoded.
* We only consider fixed options that we would send every
* time I.e. SACK is not considered. This is important
* for cc modules to figure out what the modulo of the
* cwnd should be.
*/
if (TCPS_HAVEESTABLISHED(tp->t_state)) {
if (tp->t_flags & TF_RCVD_TSTMP)
optlen = TCPOLEN_TSTAMP_APPA;
else
optlen = 0;
#if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
if (tp->t_flags & TF_SIGNATURE)
optlen += PADTCPOLEN(TCPOLEN_SIGNATURE);
#endif
} else {
if (tp->t_flags & TF_REQ_TSTMP)
optlen = TCPOLEN_TSTAMP_APPA;
else
optlen = PADTCPOLEN(TCPOLEN_MAXSEG);
if (tp->t_flags & TF_REQ_SCALE)
optlen += PADTCPOLEN(TCPOLEN_WINDOW);
#if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
if (tp->t_flags & TF_SIGNATURE)
optlen += PADTCPOLEN(TCPOLEN_SIGNATURE);
#endif
if (tp->t_flags & TF_SACK_PERMIT)
optlen += PADTCPOLEN(TCPOLEN_SACK_PERMITTED);
}
optlen = min(optlen, TCP_MAXOLEN);
return (tp->t_maxseg - optlen);
}
static int
sysctl_drop(SYSCTL_HANDLER_ARGS)
{
/* addrs[0] is a foreign socket, addrs[1] is a local one. */
struct sockaddr_storage addrs[2];
struct inpcb *inp;
struct tcpcb *tp;
#ifdef INET
struct sockaddr_in *fin = NULL, *lin = NULL;
#endif
struct epoch_tracker et;
#ifdef INET6
struct sockaddr_in6 *fin6, *lin6;
#endif
int error;
inp = NULL;
#ifdef INET6
fin6 = lin6 = NULL;
#endif
error = 0;
if (req->oldptr != NULL || req->oldlen != 0)
return (EINVAL);
if (req->newptr == NULL)
return (EPERM);
if (req->newlen < sizeof(addrs))
return (ENOMEM);
error = SYSCTL_IN(req, &addrs, sizeof(addrs));
if (error)
return (error);
switch (addrs[0].ss_family) {
#ifdef INET6
case AF_INET6:
fin6 = (struct sockaddr_in6 *)&addrs[0];
lin6 = (struct sockaddr_in6 *)&addrs[1];
if (fin6->sin6_len != sizeof(struct sockaddr_in6) ||
lin6->sin6_len != sizeof(struct sockaddr_in6))
return (EINVAL);
if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) {
if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr))
return (EINVAL);
in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]);
in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]);
#ifdef INET
fin = (struct sockaddr_in *)&addrs[0];
lin = (struct sockaddr_in *)&addrs[1];
#endif
break;
}
error = sa6_embedscope(fin6, V_ip6_use_defzone);
if (error)
return (error);
error = sa6_embedscope(lin6, V_ip6_use_defzone);
if (error)
return (error);
break;
#endif
#ifdef INET
case AF_INET:
fin = (struct sockaddr_in *)&addrs[0];
lin = (struct sockaddr_in *)&addrs[1];
if (fin->sin_len != sizeof(struct sockaddr_in) ||
lin->sin_len != sizeof(struct sockaddr_in))
return (EINVAL);
break;
#endif
default:
return (EINVAL);
}
NET_EPOCH_ENTER(et);
switch (addrs[0].ss_family) {
#ifdef INET6
case AF_INET6:
inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr,
fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port,
INPLOOKUP_WLOCKPCB, NULL);
break;
#endif
#ifdef INET
case AF_INET:
inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port,
lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL);
break;
#endif
}
if (inp != NULL) {
if (!SOLISTENING(inp->inp_socket)) {
tp = intotcpcb(inp);
tp = tcp_drop(tp, ECONNABORTED);
if (tp != NULL)
INP_WUNLOCK(inp);
} else
INP_WUNLOCK(inp);
} else
error = ESRCH;
NET_EPOCH_EXIT(et);
return (error);
}
SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop,
CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP |
CTLFLAG_NEEDGIANT, NULL, 0, sysctl_drop, "",
"Drop TCP connection");
static int
tcp_sysctl_setsockopt(SYSCTL_HANDLER_ARGS)
{
return (sysctl_setsockopt(oidp, arg1, arg2, req, &V_tcbinfo,
&tcp_ctloutput_set));
}
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, setsockopt,
CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP |
CTLFLAG_MPSAFE, NULL, 0, tcp_sysctl_setsockopt, "",
"Set socket option for TCP endpoint");
#ifdef KERN_TLS
static int
sysctl_switch_tls(SYSCTL_HANDLER_ARGS)
{
/* addrs[0] is a foreign socket, addrs[1] is a local one. */
struct sockaddr_storage addrs[2];
struct inpcb *inp;
#ifdef INET
struct sockaddr_in *fin = NULL, *lin = NULL;
#endif
struct epoch_tracker et;
#ifdef INET6
struct sockaddr_in6 *fin6, *lin6;
#endif
int error;
inp = NULL;
#ifdef INET6
fin6 = lin6 = NULL;
#endif
error = 0;
if (req->oldptr != NULL || req->oldlen != 0)
return (EINVAL);
if (req->newptr == NULL)
return (EPERM);
if (req->newlen < sizeof(addrs))
return (ENOMEM);
error = SYSCTL_IN(req, &addrs, sizeof(addrs));
if (error)
return (error);
switch (addrs[0].ss_family) {
#ifdef INET6
case AF_INET6:
fin6 = (struct sockaddr_in6 *)&addrs[0];
lin6 = (struct sockaddr_in6 *)&addrs[1];
if (fin6->sin6_len != sizeof(struct sockaddr_in6) ||
lin6->sin6_len != sizeof(struct sockaddr_in6))
return (EINVAL);
if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) {
if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr))
return (EINVAL);
in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]);
in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]);
#ifdef INET
fin = (struct sockaddr_in *)&addrs[0];
lin = (struct sockaddr_in *)&addrs[1];
#endif
break;
}
error = sa6_embedscope(fin6, V_ip6_use_defzone);
if (error)
return (error);
error = sa6_embedscope(lin6, V_ip6_use_defzone);
if (error)
return (error);
break;
#endif
#ifdef INET
case AF_INET:
fin = (struct sockaddr_in *)&addrs[0];
lin = (struct sockaddr_in *)&addrs[1];
if (fin->sin_len != sizeof(struct sockaddr_in) ||
lin->sin_len != sizeof(struct sockaddr_in))
return (EINVAL);
break;
#endif
default:
return (EINVAL);
}
NET_EPOCH_ENTER(et);
switch (addrs[0].ss_family) {
#ifdef INET6
case AF_INET6:
inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr,
fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port,
INPLOOKUP_WLOCKPCB, NULL);
break;
#endif
#ifdef INET
case AF_INET:
inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port,
lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL);
break;
#endif
}
NET_EPOCH_EXIT(et);
if (inp != NULL) {
struct socket *so;
so = inp->inp_socket;
soref(so);
error = ktls_set_tx_mode(so,
arg2 == 0 ? TCP_TLS_MODE_SW : TCP_TLS_MODE_IFNET);
INP_WUNLOCK(inp);
sorele(so);
} else
error = ESRCH;
return (error);
}
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_sw_tls,
CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP |
CTLFLAG_NEEDGIANT, NULL, 0, sysctl_switch_tls, "",
"Switch TCP connection to SW TLS");
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_ifnet_tls,
CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP |
CTLFLAG_NEEDGIANT, NULL, 1, sysctl_switch_tls, "",
"Switch TCP connection to ifnet TLS");
#endif
/*
* Generate a standardized TCP log line for use throughout the
* tcp subsystem. Memory allocation is done with M_NOWAIT to
* allow use in the interrupt context.
*
* NB: The caller MUST free(s, M_TCPLOG) the returned string.
* NB: The function may return NULL if memory allocation failed.
*
* Due to header inclusion and ordering limitations the struct ip
* and ip6_hdr pointers have to be passed as void pointers.
*/
char *
tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr,
const void *ip6hdr)
{
/* Is logging enabled? */
if (V_tcp_log_in_vain == 0)
return (NULL);
return (tcp_log_addr(inc, th, ip4hdr, ip6hdr));
}
char *
tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr,
const void *ip6hdr)
{
/* Is logging enabled? */
if (tcp_log_debug == 0)
return (NULL);
return (tcp_log_addr(inc, th, ip4hdr, ip6hdr));
}
static char *
tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr,
const void *ip6hdr)
{
char *s, *sp;
size_t size;
#ifdef INET
const struct ip *ip = (const struct ip *)ip4hdr;
#endif
#ifdef INET6
const struct ip6_hdr *ip6 = (const struct ip6_hdr *)ip6hdr;
#endif /* INET6 */
/*
* The log line looks like this:
* "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>"
*/
size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") +
sizeof(PRINT_TH_FLAGS) + 1 +
#ifdef INET6
2 * INET6_ADDRSTRLEN;
#else
2 * INET_ADDRSTRLEN;
#endif /* INET6 */
s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT);
if (s == NULL)
return (NULL);
strcat(s, "TCP: [");
sp = s + strlen(s);
if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) {
inet_ntoa_r(inc->inc_faddr, sp);
sp = s + strlen(s);
sprintf(sp, "]:%i to [", ntohs(inc->inc_fport));
sp = s + strlen(s);
inet_ntoa_r(inc->inc_laddr, sp);
sp = s + strlen(s);
sprintf(sp, "]:%i", ntohs(inc->inc_lport));
#ifdef INET6
} else if (inc) {
ip6_sprintf(sp, &inc->inc6_faddr);
sp = s + strlen(s);
sprintf(sp, "]:%i to [", ntohs(inc->inc_fport));
sp = s + strlen(s);
ip6_sprintf(sp, &inc->inc6_laddr);
sp = s + strlen(s);
sprintf(sp, "]:%i", ntohs(inc->inc_lport));
} else if (ip6 && th) {
ip6_sprintf(sp, &ip6->ip6_src);
sp = s + strlen(s);
sprintf(sp, "]:%i to [", ntohs(th->th_sport));
sp = s + strlen(s);
ip6_sprintf(sp, &ip6->ip6_dst);
sp = s + strlen(s);
sprintf(sp, "]:%i", ntohs(th->th_dport));
#endif /* INET6 */
#ifdef INET
} else if (ip && th) {
inet_ntoa_r(ip->ip_src, sp);
sp = s + strlen(s);
sprintf(sp, "]:%i to [", ntohs(th->th_sport));
sp = s + strlen(s);
inet_ntoa_r(ip->ip_dst, sp);
sp = s + strlen(s);
sprintf(sp, "]:%i", ntohs(th->th_dport));
#endif /* INET */
} else {
free(s, M_TCPLOG);
return (NULL);
}
sp = s + strlen(s);
if (th)
sprintf(sp, " tcpflags 0x%b", tcp_get_flags(th), PRINT_TH_FLAGS);
if (*(s + size - 1) != '\0')
panic("%s: string too long", __func__);
return (s);
}
/*
* A subroutine which makes it easy to track TCP state changes with DTrace.
* This function shouldn't be called for t_state initializations that don't
* correspond to actual TCP state transitions.
*/
void
tcp_state_change(struct tcpcb *tp, int newstate)
{
#if defined(KDTRACE_HOOKS)
int pstate = tp->t_state;
#endif
TCPSTATES_DEC(tp->t_state);
TCPSTATES_INC(newstate);
tp->t_state = newstate;
TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate);
}
/*
* Create an external-format (``xtcpcb'') structure using the information in
* the kernel-format tcpcb structure pointed to by tp. This is done to
* reduce the spew of irrelevant information over this interface, to isolate
* user code from changes in the kernel structure, and potentially to provide
* information-hiding if we decide that some of this information should be
* hidden from users.
*/
void
tcp_inptoxtp(const struct inpcb *inp, struct xtcpcb *xt)
{
struct tcpcb *tp = intotcpcb(inp);
sbintime_t now;
bzero(xt, sizeof(*xt));
xt->t_state = tp->t_state;
xt->t_logstate = tcp_get_bblog_state(tp);
xt->t_flags = tp->t_flags;
xt->t_sndzerowin = tp->t_sndzerowin;
xt->t_sndrexmitpack = tp->t_sndrexmitpack;
xt->t_rcvoopack = tp->t_rcvoopack;
xt->t_rcv_wnd = tp->rcv_wnd;
xt->t_snd_wnd = tp->snd_wnd;
xt->t_snd_cwnd = tp->snd_cwnd;
xt->t_snd_ssthresh = tp->snd_ssthresh;
xt->t_dsack_bytes = tp->t_dsack_bytes;
xt->t_dsack_tlp_bytes = tp->t_dsack_tlp_bytes;
xt->t_dsack_pack = tp->t_dsack_pack;
xt->t_maxseg = tp->t_maxseg;
xt->xt_ecn = (tp->t_flags2 & TF2_ECN_PERMIT) ? 1 : 0 +
(tp->t_flags2 & TF2_ACE_PERMIT) ? 2 : 0;
now = getsbinuptime();
#define COPYTIMER(which,where) do { \
if (tp->t_timers[which] != SBT_MAX) \
xt->where = (tp->t_timers[which] - now) / SBT_1MS; \
else \
xt->where = 0; \
} while (0)
COPYTIMER(TT_DELACK, tt_delack);
COPYTIMER(TT_REXMT, tt_rexmt);
COPYTIMER(TT_PERSIST, tt_persist);
COPYTIMER(TT_KEEP, tt_keep);
COPYTIMER(TT_2MSL, tt_2msl);
#undef COPYTIMER
xt->t_rcvtime = 1000 * (ticks - tp->t_rcvtime) / hz;
xt->xt_encaps_port = tp->t_port;
bcopy(tp->t_fb->tfb_tcp_block_name, xt->xt_stack,
TCP_FUNCTION_NAME_LEN_MAX);
bcopy(CC_ALGO(tp)->name, xt->xt_cc, TCP_CA_NAME_MAX);
#ifdef TCP_BLACKBOX
(void)tcp_log_get_id(tp, xt->xt_logid);
#endif
xt->xt_len = sizeof(struct xtcpcb);
in_pcbtoxinpcb(inp, &xt->xt_inp);
}
void
tcp_log_end_status(struct tcpcb *tp, uint8_t status)
{
uint32_t bit, i;
if ((tp == NULL) ||
(status > TCP_EI_STATUS_MAX_VALUE) ||
(status == 0)) {
/* Invalid */
return;
}
if (status > (sizeof(uint32_t) * 8)) {
/* Should this be a KASSERT? */
return;
}
bit = 1U << (status - 1);
if (bit & tp->t_end_info_status) {
/* already logged */
return;
}
for (i = 0; i < TCP_END_BYTE_INFO; i++) {
if (tp->t_end_info_bytes[i] == TCP_EI_EMPTY_SLOT) {
tp->t_end_info_bytes[i] = status;
tp->t_end_info_status |= bit;
break;
}
}
}
int
tcp_can_enable_pacing(void)
{
if ((tcp_pacing_limit == -1) ||
(tcp_pacing_limit > number_of_tcp_connections_pacing)) {
atomic_fetchadd_int(&number_of_tcp_connections_pacing, 1);
shadow_num_connections = number_of_tcp_connections_pacing;
return (1);
} else {
counter_u64_add(tcp_pacing_failures, 1);
return (0);
}
}
int
tcp_incr_dgp_pacing_cnt(void)
{
if ((tcp_dgp_limit == -1) ||
(tcp_dgp_limit > number_of_dgp_connections)) {
atomic_fetchadd_int(&number_of_dgp_connections, 1);
shadow_tcp_pacing_dgp = number_of_dgp_connections;
return (1);
} else {
counter_u64_add(tcp_dgp_failures, 1);
return (0);
}
}
static uint8_t tcp_dgp_warning = 0;
void
tcp_dec_dgp_pacing_cnt(void)
{
uint32_t ret;
ret = atomic_fetchadd_int(&number_of_dgp_connections, -1);
shadow_tcp_pacing_dgp = number_of_dgp_connections;
KASSERT(ret != 0, ("number_of_dgp_connections -1 would cause wrap?"));
if (ret == 0) {
if (tcp_dgp_limit != -1) {
printf("Warning all DGP is now disabled, count decrements invalidly!\n");
tcp_dgp_limit = 0;
tcp_dgp_warning = 1;
} else if (tcp_dgp_warning == 0) {
printf("Warning DGP pacing is invalid, invalid decrement\n");
tcp_dgp_warning = 1;
}
}
}
static uint8_t tcp_pacing_warning = 0;
void
tcp_decrement_paced_conn(void)
{
uint32_t ret;
ret = atomic_fetchadd_int(&number_of_tcp_connections_pacing, -1);
shadow_num_connections = number_of_tcp_connections_pacing;
KASSERT(ret != 0, ("tcp_paced_connection_exits -1 would cause wrap?"));
if (ret == 0) {
if (tcp_pacing_limit != -1) {
printf("Warning all pacing is now disabled, count decrements invalidly!\n");
tcp_pacing_limit = 0;
} else if (tcp_pacing_warning == 0) {
printf("Warning pacing count is invalid, invalid decrement\n");
tcp_pacing_warning = 1;
}
}
}
static void
tcp_default_switch_failed(struct tcpcb *tp)
{
/*
* If a switch fails we only need to
* care about two things:
* a) The t_flags2
* and
* b) The timer granularity.
* Timeouts, at least for now, don't use the
* old callout system in the other stacks so
* those are hopefully safe.
*/
tcp_lro_features_off(tp);
tcp_change_time_units(tp, TCP_TMR_GRANULARITY_TICKS);
}
#ifdef TCP_ACCOUNTING
int
tcp_do_ack_accounting(struct tcpcb *tp, struct tcphdr *th, struct tcpopt *to, uint32_t tiwin, int mss)
{
if (SEQ_LT(th->th_ack, tp->snd_una)) {
/* Do we have a SACK? */
if (to->to_flags & TOF_SACK) {
if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
tp->tcp_cnt_counters[ACK_SACK]++;
}
return (ACK_SACK);
} else {
if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
tp->tcp_cnt_counters[ACK_BEHIND]++;
}
return (ACK_BEHIND);
}
} else if (th->th_ack == tp->snd_una) {
/* Do we have a SACK? */
if (to->to_flags & TOF_SACK) {
if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
tp->tcp_cnt_counters[ACK_SACK]++;
}
return (ACK_SACK);
} else if (tiwin != tp->snd_wnd) {
if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
tp->tcp_cnt_counters[ACK_RWND]++;
}
return (ACK_RWND);
} else {
if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
tp->tcp_cnt_counters[ACK_DUPACK]++;
}
return (ACK_DUPACK);
}
} else {
if (!SEQ_GT(th->th_ack, tp->snd_max)) {
if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
tp->tcp_cnt_counters[CNT_OF_ACKS_IN] += (((th->th_ack - tp->snd_una) + mss - 1)/mss);
}
}
if (to->to_flags & TOF_SACK) {
if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
tp->tcp_cnt_counters[ACK_CUMACK_SACK]++;
}
return (ACK_CUMACK_SACK);
} else {
if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
tp->tcp_cnt_counters[ACK_CUMACK]++;
}
return (ACK_CUMACK);
}
}
}
#endif
void
tcp_change_time_units(struct tcpcb *tp, int granularity)
{
if (tp->t_tmr_granularity == granularity) {
/* We are there */
return;
}
if (granularity == TCP_TMR_GRANULARITY_USEC) {
KASSERT((tp->t_tmr_granularity == TCP_TMR_GRANULARITY_TICKS),
("Granularity is not TICKS its %u in tp:%p",
tp->t_tmr_granularity, tp));
tp->t_rttlow = TICKS_2_USEC(tp->t_rttlow);
if (tp->t_srtt > 1) {
uint32_t val, frac;
val = tp->t_srtt >> TCP_RTT_SHIFT;
frac = tp->t_srtt & 0x1f;
tp->t_srtt = TICKS_2_USEC(val);
/*
* frac is the fractional part of the srtt (if any)
* but its in ticks and every bit represents
* 1/32nd of a hz.
*/
if (frac) {
if (hz == 1000) {
frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE);
} else {
frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE));
}
tp->t_srtt += frac;
}
}
if (tp->t_rttvar) {
uint32_t val, frac;
val = tp->t_rttvar >> TCP_RTTVAR_SHIFT;
frac = tp->t_rttvar & 0x1f;
tp->t_rttvar = TICKS_2_USEC(val);
/*
* frac is the fractional part of the srtt (if any)
* but its in ticks and every bit represents
* 1/32nd of a hz.
*/
if (frac) {
if (hz == 1000) {
frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE);
} else {
frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE));
}
tp->t_rttvar += frac;
}
}
tp->t_tmr_granularity = TCP_TMR_GRANULARITY_USEC;
} else if (granularity == TCP_TMR_GRANULARITY_TICKS) {
/* Convert back to ticks, with */
KASSERT((tp->t_tmr_granularity == TCP_TMR_GRANULARITY_USEC),
("Granularity is not USEC its %u in tp:%p",
tp->t_tmr_granularity, tp));
if (tp->t_srtt > 1) {
uint32_t val, frac;
val = USEC_2_TICKS(tp->t_srtt);
frac = tp->t_srtt % (HPTS_USEC_IN_SEC / hz);
tp->t_srtt = val << TCP_RTT_SHIFT;
/*
* frac is the fractional part here is left
* over from converting to hz and shifting.
* We need to convert this to the 5 bit
* remainder.
*/
if (frac) {
if (hz == 1000) {
frac = (((uint64_t)frac * (uint64_t)TCP_RTT_SCALE) / (uint64_t)HPTS_USEC_IN_MSEC);
} else {
frac = (((uint64_t)frac * (uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE) /(uint64_t)HPTS_USEC_IN_SEC);
}
tp->t_srtt += frac;
}
}
if (tp->t_rttvar) {
uint32_t val, frac;
val = USEC_2_TICKS(tp->t_rttvar);
frac = tp->t_rttvar % (HPTS_USEC_IN_SEC / hz);
tp->t_rttvar = val << TCP_RTTVAR_SHIFT;
/*
* frac is the fractional part here is left
* over from converting to hz and shifting.
* We need to convert this to the 4 bit
* remainder.
*/
if (frac) {
if (hz == 1000) {
frac = (((uint64_t)frac * (uint64_t)TCP_RTTVAR_SCALE) / (uint64_t)HPTS_USEC_IN_MSEC);
} else {
frac = (((uint64_t)frac * (uint64_t)(hz) * (uint64_t)TCP_RTTVAR_SCALE) /(uint64_t)HPTS_USEC_IN_SEC);
}
tp->t_rttvar += frac;
}
}
tp->t_rttlow = USEC_2_TICKS(tp->t_rttlow);
tp->t_tmr_granularity = TCP_TMR_GRANULARITY_TICKS;
}
#ifdef INVARIANTS
else {
panic("Unknown granularity:%d tp:%p",
granularity, tp);
}
#endif
}
void
tcp_handle_orphaned_packets(struct tcpcb *tp)
{
struct mbuf *save, *m, *prev;
/*
* Called when a stack switch is occuring from the fini()
* of the old stack. We assue the init() as already been
* run of the new stack and it has set the t_flags2 to
* what it supports. This function will then deal with any
* differences i.e. cleanup packets that maybe queued that
* the newstack does not support.
*/
if (tp->t_flags2 & TF2_MBUF_L_ACKS)
return;
if ((tp->t_flags2 & TF2_SUPPORTS_MBUFQ) == 0 &&
!STAILQ_EMPTY(&tp->t_inqueue)) {
/*
* It is unsafe to process the packets since a
* reset may be lurking in them (its rare but it
* can occur). If we were to find a RST, then we
* would end up dropping the connection and the
* INP lock, so when we return the caller (tcp_usrreq)
* will blow up when it trys to unlock the inp.
* This new stack does not do any fancy LRO features
* so all we can do is toss the packets.
*/
m = STAILQ_FIRST(&tp->t_inqueue);
STAILQ_INIT(&tp->t_inqueue);
STAILQ_FOREACH_FROM_SAFE(m, &tp->t_inqueue, m_stailqpkt, save)
m_freem(m);
} else {
/*
* Here we have a stack that does mbuf queuing but
* does not support compressed ack's. We must
* walk all the mbufs and discard any compressed acks.
*/
STAILQ_FOREACH_SAFE(m, &tp->t_inqueue, m_stailqpkt, save) {
if (m->m_flags & M_ACKCMP) {
if (m == STAILQ_FIRST(&tp->t_inqueue))
STAILQ_REMOVE_HEAD(&tp->t_inqueue,
m_stailqpkt);
else
STAILQ_REMOVE_AFTER(&tp->t_inqueue,
prev, m_stailqpkt);
m_freem(m);
} else
prev = m;
}
}
}
#ifdef TCP_REQUEST_TRK
uint32_t
tcp_estimate_tls_overhead(struct socket *so, uint64_t tls_usr_bytes)
{
#ifdef KERN_TLS
struct ktls_session *tls;
uint32_t rec_oh, records;
tls = so->so_snd.sb_tls_info;
if (tls == NULL)
return (0);
rec_oh = tls->params.tls_hlen + tls->params.tls_tlen;
records = ((tls_usr_bytes + tls->params.max_frame_len - 1)/tls->params.max_frame_len);
return (records * rec_oh);
#else
return (0);
#endif
}
extern uint32_t tcp_stale_entry_time;
uint32_t tcp_stale_entry_time = 250000;
SYSCTL_UINT(_net_inet_tcp, OID_AUTO, usrlog_stale, CTLFLAG_RW,
&tcp_stale_entry_time, 250000, "Time that a tcpreq entry without a sendfile ages out");
void
tcp_req_log_req_info(struct tcpcb *tp, struct tcp_sendfile_track *req,
uint16_t slot, uint8_t val, uint64_t offset, uint64_t nbytes)
{
if (tcp_bblogging_on(tp)) {
union tcp_log_stackspecific log;
struct timeval tv;
memset(&log.u_bbr, 0, sizeof(log.u_bbr));
log.u_bbr.inhpts = tcp_in_hpts(tp);
log.u_bbr.flex8 = val;
log.u_bbr.rttProp = req->timestamp;
log.u_bbr.delRate = req->start;
log.u_bbr.cur_del_rate = req->end;
log.u_bbr.flex1 = req->start_seq;
log.u_bbr.flex2 = req->end_seq;
log.u_bbr.flex3 = req->flags;
log.u_bbr.flex4 = ((req->localtime >> 32) & 0x00000000ffffffff);
log.u_bbr.flex5 = (req->localtime & 0x00000000ffffffff);
log.u_bbr.flex7 = slot;
log.u_bbr.bw_inuse = offset;
/* nbytes = flex6 | epoch */
log.u_bbr.flex6 = ((nbytes >> 32) & 0x00000000ffffffff);
log.u_bbr.epoch = (nbytes & 0x00000000ffffffff);
/* cspr = lt_epoch | pkts_out */
log.u_bbr.lt_epoch = ((req->cspr >> 32) & 0x00000000ffffffff);
log.u_bbr.pkts_out |= (req->cspr & 0x00000000ffffffff);
log.u_bbr.applimited = tp->t_tcpreq_closed;
log.u_bbr.applimited <<= 8;
log.u_bbr.applimited |= tp->t_tcpreq_open;
log.u_bbr.applimited <<= 8;
log.u_bbr.applimited |= tp->t_tcpreq_req;
log.u_bbr.timeStamp = tcp_get_usecs(&tv);
TCP_LOG_EVENTP(tp, NULL,
&tptosocket(tp)->so_rcv,
&tptosocket(tp)->so_snd,
TCP_LOG_REQ_T, 0,
0, &log, false, &tv);
}
}
void
tcp_req_free_a_slot(struct tcpcb *tp, struct tcp_sendfile_track *ent)
{
if (tp->t_tcpreq_req > 0)
tp->t_tcpreq_req--;
if (ent->flags & TCP_TRK_TRACK_FLG_OPEN) {
if (tp->t_tcpreq_open > 0)
tp->t_tcpreq_open--;
} else {
if (tp->t_tcpreq_closed > 0)
tp->t_tcpreq_closed--;
}
ent->flags = TCP_TRK_TRACK_FLG_EMPTY;
}
static void
tcp_req_check_for_stale_entries(struct tcpcb *tp, uint64_t ts, int rm_oldest)
{
struct tcp_sendfile_track *ent;
uint64_t time_delta, oldest_delta;
int i, oldest, oldest_set = 0, cnt_rm = 0;
for (i = 0; i < MAX_TCP_TRK_REQ; i++) {
ent = &tp->t_tcpreq_info[i];
if (ent->flags != TCP_TRK_TRACK_FLG_USED) {
/*
* We only care about closed end ranges
* that are allocated and have no sendfile
* ever touching them. They would be in
* state USED.
*/
continue;
}
if (ts >= ent->localtime)
time_delta = ts - ent->localtime;
else
time_delta = 0;
if (time_delta &&
((oldest_delta < time_delta) || (oldest_set == 0))) {
oldest_set = 1;
oldest = i;
oldest_delta = time_delta;
}
if (tcp_stale_entry_time && (time_delta >= tcp_stale_entry_time)) {
/*
* No sendfile in a our time-limit
* time to purge it.
*/
cnt_rm++;
tcp_req_log_req_info(tp, &tp->t_tcpreq_info[i], i, TCP_TRK_REQ_LOG_STALE,
time_delta, 0);
tcp_req_free_a_slot(tp, ent);
}
}
if ((cnt_rm == 0) && rm_oldest && oldest_set) {
ent = &tp->t_tcpreq_info[oldest];
tcp_req_log_req_info(tp, &tp->t_tcpreq_info[i], i, TCP_TRK_REQ_LOG_STALE,
oldest_delta, 1);
tcp_req_free_a_slot(tp, ent);
}
}
int
tcp_req_check_for_comp(struct tcpcb *tp, tcp_seq ack_point)
{
int i, ret = 0;
struct tcp_sendfile_track *ent;
/* Clean up any old closed end requests that are now completed */
if (tp->t_tcpreq_req == 0)
return (0);
if (tp->t_tcpreq_closed == 0)
return (0);
for (i = 0; i < MAX_TCP_TRK_REQ; i++) {
ent = &tp->t_tcpreq_info[i];
/* Skip empty ones */
if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY)
continue;
/* Skip open ones */
if (ent->flags & TCP_TRK_TRACK_FLG_OPEN)
continue;
if (SEQ_GEQ(ack_point, ent->end_seq)) {
/* We are past it -- free it */
tcp_req_log_req_info(tp, ent,
i, TCP_TRK_REQ_LOG_FREED, 0, 0);
tcp_req_free_a_slot(tp, ent);
ret++;
}
}
return (ret);
}
int
tcp_req_is_entry_comp(struct tcpcb *tp, struct tcp_sendfile_track *ent, tcp_seq ack_point)
{
if (tp->t_tcpreq_req == 0)
return (-1);
if (tp->t_tcpreq_closed == 0)
return (-1);
if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY)
return (-1);
if (SEQ_GEQ(ack_point, ent->end_seq)) {
return (1);
}
return (0);
}
struct tcp_sendfile_track *
tcp_req_find_a_req_that_is_completed_by(struct tcpcb *tp, tcp_seq th_ack, int *ip)
{
/*
* Given an ack point (th_ack) walk through our entries and
* return the first one found that th_ack goes past the
* end_seq.
*/
struct tcp_sendfile_track *ent;
int i;
if (tp->t_tcpreq_req == 0) {
/* none open */
return (NULL);
}
for (i = 0; i < MAX_TCP_TRK_REQ; i++) {
ent = &tp->t_tcpreq_info[i];
if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY)
continue;
if ((ent->flags & TCP_TRK_TRACK_FLG_OPEN) == 0) {
if (SEQ_GEQ(th_ack, ent->end_seq)) {
*ip = i;
return (ent);
}
}
}
return (NULL);
}
struct tcp_sendfile_track *
tcp_req_find_req_for_seq(struct tcpcb *tp, tcp_seq seq)
{
struct tcp_sendfile_track *ent;
int i;
if (tp->t_tcpreq_req == 0) {
/* none open */
return (NULL);
}
for (i = 0; i < MAX_TCP_TRK_REQ; i++) {
ent = &tp->t_tcpreq_info[i];
tcp_req_log_req_info(tp, ent, i, TCP_TRK_REQ_LOG_SEARCH,
(uint64_t)seq, 0);
if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY) {
continue;
}
if (ent->flags & TCP_TRK_TRACK_FLG_OPEN) {
/*
* An open end request only needs to
* match the beginning seq or be
* all we have (once we keep going on
* a open end request we may have a seq
* wrap).
*/
if ((SEQ_GEQ(seq, ent->start_seq)) ||
(tp->t_tcpreq_closed == 0))
return (ent);
} else {
/*
* For this one we need to
* be a bit more careful if its
* completed at least.
*/
if ((SEQ_GEQ(seq, ent->start_seq)) &&
(SEQ_LT(seq, ent->end_seq))) {
return (ent);
}
}
}
return (NULL);
}
/* Should this be in its own file tcp_req.c ? */
struct tcp_sendfile_track *
tcp_req_alloc_req_full(struct tcpcb *tp, struct tcp_snd_req *req, uint64_t ts, int rec_dups)
{
struct tcp_sendfile_track *fil;
int i, allocated;
/* In case the stack does not check for completions do so now */
tcp_req_check_for_comp(tp, tp->snd_una);
/* Check for stale entries */
if (tp->t_tcpreq_req)
tcp_req_check_for_stale_entries(tp, ts,
(tp->t_tcpreq_req >= MAX_TCP_TRK_REQ));
/* Check to see if this is a duplicate of one not started */
if (tp->t_tcpreq_req) {
for (i = 0, allocated = 0; i < MAX_TCP_TRK_REQ; i++) {
fil = &tp->t_tcpreq_info[i];
if ((fil->flags & TCP_TRK_TRACK_FLG_USED) == 0)
continue;
if ((fil->timestamp == req->timestamp) &&
(fil->start == req->start) &&
((fil->flags & TCP_TRK_TRACK_FLG_OPEN) ||
(fil->end == req->end))) {
/*
* We already have this request
* and it has not been started with sendfile.
* This probably means the user was returned
* a 4xx of some sort and its going to age
* out, lets not duplicate it.
*/
return (fil);
}
}
}
/* Ok if there is no room at the inn we are in trouble */
if (tp->t_tcpreq_req >= MAX_TCP_TRK_REQ) {
tcp_trace_point(tp, TCP_TP_REQ_LOG_FAIL);
for (i = 0; i < MAX_TCP_TRK_REQ; i++) {
tcp_req_log_req_info(tp, &tp->t_tcpreq_info[i],
i, TCP_TRK_REQ_LOG_ALLOCFAIL, 0, 0);
}
return (NULL);
}
for (i = 0, allocated = 0; i < MAX_TCP_TRK_REQ; i++) {
fil = &tp->t_tcpreq_info[i];
if (fil->flags == TCP_TRK_TRACK_FLG_EMPTY) {
allocated = 1;
fil->flags = TCP_TRK_TRACK_FLG_USED;
fil->timestamp = req->timestamp;
fil->playout_ms = req->playout_ms;
fil->localtime = ts;
fil->start = req->start;
if (req->flags & TCP_LOG_HTTPD_RANGE_END) {
fil->end = req->end;
} else {
fil->end = 0;
fil->flags |= TCP_TRK_TRACK_FLG_OPEN;
}
/*
* We can set the min boundaries to the TCP Sequence space,
* but it might be found to be further up when sendfile
* actually runs on this range (if it ever does).
*/
fil->sbcc_at_s = tptosocket(tp)->so_snd.sb_ccc;
fil->start_seq = tp->snd_una +
tptosocket(tp)->so_snd.sb_ccc;
if (req->flags & TCP_LOG_HTTPD_RANGE_END)
fil->end_seq = (fil->start_seq + ((uint32_t)(fil->end - fil->start)));
else
fil->end_seq = 0;
if (tptosocket(tp)->so_snd.sb_tls_info) {
/*
* This session is doing TLS. Take a swag guess
* at the overhead.
*/
fil->end_seq += tcp_estimate_tls_overhead(
tptosocket(tp), (fil->end - fil->start));
}
tp->t_tcpreq_req++;
if (fil->flags & TCP_TRK_TRACK_FLG_OPEN)
tp->t_tcpreq_open++;
else
tp->t_tcpreq_closed++;
tcp_req_log_req_info(tp, fil, i,
TCP_TRK_REQ_LOG_NEW, 0, 0);
break;
} else
fil = NULL;
}
return (fil);
}
void
tcp_req_alloc_req(struct tcpcb *tp, union tcp_log_userdata *user, uint64_t ts)
{
(void)tcp_req_alloc_req_full(tp, &user->tcp_req, ts, 1);
}
#endif
void
tcp_log_socket_option(struct tcpcb *tp, uint32_t option_num, uint32_t option_val, int err)
{
if (tcp_bblogging_on(tp)) {
struct tcp_log_buffer *l;
l = tcp_log_event(tp, NULL,
&tptosocket(tp)->so_rcv,
&tptosocket(tp)->so_snd,
TCP_LOG_SOCKET_OPT,
err, 0, NULL, 1,
NULL, NULL, 0, NULL);
if (l) {
l->tlb_flex1 = option_num;
l->tlb_flex2 = option_val;
}
}
}
uint32_t
tcp_get_srtt(struct tcpcb *tp, int granularity)
{
uint32_t srtt;
KASSERT(granularity == TCP_TMR_GRANULARITY_USEC ||
granularity == TCP_TMR_GRANULARITY_TICKS,
("%s: called with unexpected granularity %d", __func__,
granularity));
srtt = tp->t_srtt;
/*
* We only support two granularities. If the stored granularity
* does not match the granularity requested by the caller,
* convert the stored value to the requested unit of granularity.
*/
if (tp->t_tmr_granularity != granularity) {
if (granularity == TCP_TMR_GRANULARITY_USEC)
srtt = TICKS_2_USEC(srtt);
else
srtt = USEC_2_TICKS(srtt);
}
/*
* If the srtt is stored with ticks granularity, we need to
* unshift to get the actual value. We do this after the
* conversion above (if one was necessary) in order to maximize
* precision.
*/
if (tp->t_tmr_granularity == TCP_TMR_GRANULARITY_TICKS)
srtt = srtt >> TCP_RTT_SHIFT;
return (srtt);
}
void
tcp_account_for_send(struct tcpcb *tp, uint32_t len, uint8_t is_rxt,
uint8_t is_tlp, bool hw_tls)
{
if (is_tlp) {
tp->t_sndtlppack++;
tp->t_sndtlpbyte += len;
}
/* To get total bytes sent you must add t_snd_rxt_bytes to t_sndbytes */
if (is_rxt)
tp->t_snd_rxt_bytes += len;
else
tp->t_sndbytes += len;
#ifdef KERN_TLS
if (hw_tls && is_rxt && len != 0) {
uint64_t rexmit_percent;
rexmit_percent = (1000ULL * tp->t_snd_rxt_bytes) /
(10ULL * (tp->t_snd_rxt_bytes + tp->t_sndbytes));
if (rexmit_percent > ktls_ifnet_max_rexmit_pct)
ktls_disable_ifnet(tp);
}
#endif
}
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