/*
* Tcp output routine: figure out what should be sent and send it.
*/
int
tcp_output(struct tcpcb *tp)
{
struct inpcb * const inp = tp->t_inpcb;
struct socket *so = inp->inp_socket;
long len, recvwin, sendwin;
int nsacked = 0;
int off, flags, error = 0;
#ifdef TCP_SIGNATURE
int sigoff = 0;
#endif
struct mbuf *m;
struct ip *ip;
struct tcphdr *th;
u_char opt[TCP_MAXOLEN];
unsigned int ipoptlen, optlen, hdrlen;
int idle;
boolean_t sendalot;
struct ip6_hdr *ip6;
#ifdef INET6
const boolean_t isipv6 = INP_ISIPV6(inp);
#else
const boolean_t isipv6 = FALSE;
#endif
boolean_t can_tso = FALSE, use_tso;
boolean_t report_sack, idle_cwv = FALSE;
u_int segsz, tso_hlen, tso_lenmax = 0;
int segcnt = 0;
boolean_t need_sched = FALSE;
KKASSERT(so->so_port == &curthread->td_msgport);
/*
* Determine length of data that should be transmitted,
* and flags that will be used.
* If there is some data or critical controls (SYN, RST)
* to send, then transmit; otherwise, investigate further.
*/
/*
* If we have been idle for a while, the send congestion window
* could be no longer representative of the current state of the
* link; need to validate congestion window. However, we should
* not perform congestion window validation here, since we could
* be asked to send pure ACK.
*/
if (tp->snd_max == tp->snd_una &&
(ticks - tp->snd_last) >= tp->t_rxtcur && tcp_idle_restart)
idle_cwv = TRUE;
/*
* Calculate whether the transmit stream was previously idle
* and adjust TF_LASTIDLE for the next time.
*/
idle = (tp->t_flags & TF_LASTIDLE) || (tp->snd_max == tp->snd_una);
if (idle && (tp->t_flags & TF_MORETOCOME))
tp->t_flags |= TF_LASTIDLE;
else
tp->t_flags &= ~TF_LASTIDLE;
if (TCP_DO_SACK(tp) && tp->snd_nxt != tp->snd_max &&
!IN_FASTRECOVERY(tp))
nsacked = tcp_sack_bytes_below(&tp->scb, tp->snd_nxt);
/*
* Find out whether TSO could be used or not
*
* For TSO capable devices, the following assumptions apply to
* the processing of TCP flags:
* - If FIN is set on the large TCP segment, the device must set
* FIN on the last segment that it creates from the large TCP
* segment.
* - If PUSH is set on the large TCP segment, the device must set
* PUSH on the last segment that it creates from the large TCP
* segment.
*/
#if !defined(IPSEC) && !defined(FAST_IPSEC)
if (tcp_do_tso
#ifdef TCP_SIGNATURE
&& (tp->t_flags & TF_SIGNATURE) == 0
#endif
) {
if (!isipv6) {
struct rtentry *rt = inp->inp_route.ro_rt;
if (rt != NULL && (rt->rt_flags & RTF_UP) &&
(rt->rt_ifp->if_hwassist & CSUM_TSO)) {
can_tso = TRUE;
tso_lenmax = rt->rt_ifp->if_tsolen;
}
}
}
#endif /* !IPSEC && !FAST_IPSEC */
again:
m = NULL;
ip = NULL;
th = NULL;
ip6 = NULL;
if ((tp->t_flags & (TF_SACK_PERMITTED | TF_NOOPT)) ==
TF_SACK_PERMITTED &&
(!TAILQ_EMPTY(&tp->t_segq) ||
tp->reportblk.rblk_start != tp->reportblk.rblk_end))
report_sack = TRUE;
else
report_sack = FALSE;
/* Make use of SACK information when slow-starting after a RTO. */
if (TCP_DO_SACK(tp) && tp->snd_nxt != tp->snd_max &&
!IN_FASTRECOVERY(tp)) {
tcp_seq old_snd_nxt = tp->snd_nxt;
tcp_sack_skip_sacked(&tp->scb, &tp->snd_nxt);
nsacked += tp->snd_nxt - old_snd_nxt;
}
sendalot = FALSE;
off = tp->snd_nxt - tp->snd_una;
sendwin = min(tp->snd_wnd, tp->snd_cwnd + nsacked);
sendwin = min(sendwin, tp->snd_bwnd);
flags = tcp_outflags[tp->t_state];
/*
* Get standard flags, and add SYN or FIN if requested by 'hidden'
* state flags.
*/
if (tp->t_flags & TF_NEEDFIN)
flags |= TH_FIN;
if (tp->t_flags & TF_NEEDSYN)
flags |= TH_SYN;
/*
* If in persist timeout with window of 0, send 1 byte.
* Otherwise, if window is small but nonzero
* and timer expired, we will send what we can
* and go to transmit state.
*/
if (tp->t_flags & TF_FORCE) {
if (sendwin == 0) {
/*
* If we still have some data to send, then
* clear the FIN bit. Usually this would
* happen below when it realizes that we
* aren't sending all the data. However,
* if we have exactly 1 byte of unsent data,
* then it won't clear the FIN bit below,
* and if we are in persist state, we wind
* up sending the packet without recording
* that we sent the FIN bit.
*
* We can't just blindly clear the FIN bit,
* because if we don't have any more data
* to send then the probe will be the FIN
* itself.
*/
if (off < so->so_snd.ssb_cc)
flags &= ~TH_FIN;
sendwin = 1;
} else {
tcp_callout_stop(tp, tp->tt_persist);
tp->t_rxtshift = 0;
}
}
/*
* If snd_nxt == snd_max and we have transmitted a FIN, the
* offset will be > 0 even if so_snd.ssb_cc is 0, resulting in
* a negative length. This can also occur when TCP opens up
* its congestion window while receiving additional duplicate
* acks after fast-retransmit because TCP will reset snd_nxt
* to snd_max after the fast-retransmit.
*
* A negative length can also occur when we are in the
* TCPS_SYN_RECEIVED state due to a simultanious connect where
* our SYN has not been acked yet.
*
* In the normal retransmit-FIN-only case, however, snd_nxt will
* be set to snd_una, the offset will be 0, and the length may
* wind up 0.
*/
len = (long)ulmin(so->so_snd.ssb_cc, sendwin) - off;
/*
* Lop off SYN bit if it has already been sent. However, if this
* is SYN-SENT state and if segment contains data, suppress sending
* segment (sending the segment would be an option if we still
* did TAO and the remote host supported it).
*/
if ((flags & TH_SYN) && SEQ_GT(tp->snd_nxt, tp->snd_una)) {
flags &= ~TH_SYN;
off--, len++;
if (len > 0 && tp->t_state == TCPS_SYN_SENT) {
tp->t_flags &= ~(TF_ACKNOW | TF_XMITNOW);
return 0;
}
}
/*
* Be careful not to send data and/or FIN on SYN segments.
* This measure is needed to prevent interoperability problems
* with not fully conformant TCP implementations.
*/
if (flags & TH_SYN) {
len = 0;
flags &= ~TH_FIN;
}
if (len < 0) {
/*
* A negative len can occur if our FIN has been sent but not
* acked, or if we are in a simultanious connect in the
* TCPS_SYN_RECEIVED state with our SYN sent but not yet
* acked.
*
* If our window has contracted to 0 in the FIN case
* (which can only occur if we have NOT been called to
* retransmit as per code a few paragraphs up) then we
* want to shift the retransmit timer over to the
* persist timer.
*
* However, if we are in the TCPS_SYN_RECEIVED state
* (the SYN case) we will be in a simultanious connect and
* the window may be zero degeneratively. In this case we
* do not want to shift to the persist timer after the SYN
* or the SYN+ACK transmission.
*/
len = 0;
if (sendwin == 0 && tp->t_state != TCPS_SYN_RECEIVED) {
tcp_callout_stop(tp, tp->tt_rexmt);
tp->t_rxtshift = 0;
tp->snd_nxt = tp->snd_una;
if (!tcp_callout_active(tp, tp->tt_persist))
tcp_setpersist(tp);
}
}
KASSERT(len >= 0, ("%s: len < 0", __func__));
/*
* Automatic sizing of send socket buffer. Often the send buffer
* size is not optimally adjusted to the actual network conditions
* at hand (delay bandwidth product). Setting the buffer size too
* small limits throughput on links with high bandwidth and high
* delay (eg. trans-continental/oceanic links). Setting the
* buffer size too big consumes too much real kernel memory,
* especially with many connections on busy servers.
*
* The criteria to step up the send buffer one notch are:
* 1. receive window of remote host is larger than send buffer
* (with a fudge factor of 5/4th);
* 2. hiwat has not significantly exceeded bwnd (inflight)
* (bwnd is a maximal value if inflight is disabled).
* 3. send buffer is filled to 7/8th with data (so we actually
* have data to make use of it);
* 4. hiwat has not hit maximal automatic size;
* 5. our send window (slow start and cogestion controlled) is
* larger than sent but unacknowledged data in send buffer.
*
* The remote host receive window scaling factor may limit the
* growing of the send buffer before it reaches its allowed
* maximum.
*
* It scales directly with slow start or congestion window
* and does at most one step per received ACK. This fast
* scaling has the drawback of growing the send buffer beyond
* what is strictly necessary to make full use of a given
* delay*bandwith product. However testing has shown this not
* to be much of an problem. At worst we are trading wasting
* of available bandwith (the non-use of it) for wasting some
* socket buffer memory.
*
* The criteria for shrinking the buffer is based solely on
* the inflight code (snd_bwnd). If inflight is disabled,
* the buffer will not be shrinked. Note that snd_bwnd already
* has a fudge factor. Our test adds a little hysteresis.
*/
if (tcp_do_autosndbuf && (so->so_snd.ssb_flags & SSB_AUTOSIZE)) {
const int asbinc = tcp_autosndbuf_inc;
const int hiwat = so->so_snd.ssb_hiwat;
const int lowat = so->so_snd.ssb_lowat;
u_long newsize;
if ((tp->snd_wnd / 4 * 5) >= hiwat &&
so->so_snd.ssb_cc >= (hiwat / 8 * 7) &&
hiwat < tp->snd_bwnd + hiwat / 10 &&
hiwat + asbinc < tcp_autosndbuf_max &&
hiwat < (TCP_MAXWIN << tp->snd_scale) &&
sendwin >= (so->so_snd.ssb_cc -
(tp->snd_nxt - tp->snd_una))) {
newsize = ulmin(hiwat + asbinc, tcp_autosndbuf_max);
if (!ssb_reserve(&so->so_snd, newsize, so, NULL))
atomic_clear_int(&so->so_snd.ssb_flags, SSB_AUTOSIZE);
#if 0
if (newsize >= (TCP_MAXWIN << tp->snd_scale))
atomic_clear_int(&so->so_snd.ssb_flags, SSB_AUTOSIZE);
#endif
} else if ((long)tp->snd_bwnd <
(long)(hiwat * 3 / 4 - lowat - asbinc) &&
hiwat > tp->t_maxseg * 2 + asbinc &&
hiwat + asbinc >= tcp_autosndbuf_min &&
tcp_do_autosndbuf == 1) {
newsize = ulmax(hiwat - asbinc, tp->t_maxseg * 2);
ssb_reserve(&so->so_snd, newsize, so, NULL);
}
}
/*
* Don't use TSO, if:
* - Congestion window needs validation
* - There are SACK blocks to report
* - RST or SYN flags is set
* - URG will be set
*
* XXX
* Checking for SYN|RST looks overkill, just to be safe than sorry
*/
use_tso = can_tso;
if (report_sack || idle_cwv || (flags & (TH_RST | TH_SYN)))
use_tso = FALSE;
if (use_tso) {
tcp_seq ugr_nxt = tp->snd_nxt;
if ((flags & TH_FIN) && (tp->t_flags & TF_SENTFIN) &&
tp->snd_nxt == tp->snd_max)
--ugr_nxt;
if (SEQ_GT(tp->snd_up, ugr_nxt))
use_tso = FALSE;
}
if (use_tso) {
/*
* Find out segment size and header length for TSO
*/
error = tcp_tso_getsize(tp, &segsz, &tso_hlen);
if (error)
use_tso = FALSE;
}
if (!use_tso) {
segsz = tp->t_maxseg;
tso_hlen = 0; /* not used */
}
/*
* Truncate to the maximum segment length if not TSO, and ensure that
* FIN is removed if the length no longer contains the last data byte.
*/
if (len > segsz) {
if (!use_tso) {
len = segsz;
++segcnt;
} else {
int nsegs;
if (__predict_false(tso_lenmax < segsz))
tso_lenmax = segsz << 1;
/*
* Truncate TSO transfers to (IP_MAXPACKET - iphlen -
* thoff), and make sure that we send equal size
* transfers down the stack (rather than big-small-
* big-small-...).
*/
len = min(len, tso_lenmax);
nsegs = min(len, (IP_MAXPACKET - tso_hlen)) / segsz;
KKASSERT(nsegs > 0);
len = nsegs * segsz;
if (len <= segsz) {
use_tso = FALSE;
++segcnt;
} else {
segcnt += nsegs;
}
}
sendalot = TRUE;
} else {
use_tso = FALSE;
if (len > 0)
++segcnt;
}
if (SEQ_LT(tp->snd_nxt + len, tp->snd_una + so->so_snd.ssb_cc))
flags &= ~TH_FIN;
recvwin = ssb_space(&so->so_rcv);
/*
* Sender silly window avoidance. We transmit under the following
* conditions when len is non-zero:
*
* - We have a full segment
* - This is the last buffer in a write()/send() and we are
* either idle or running NODELAY
* - we've timed out (e.g. persist timer)
* - we have more then 1/2 the maximum send window's worth of
* data (receiver may be limiting the window size)
* - we need to retransmit
*/
if (len) {
if (len >= segsz)
goto send;
/*
* NOTE! on localhost connections an 'ack' from the remote
* end may occur synchronously with the output and cause
* us to flush a buffer queued with moretocome. XXX
*
* note: the len + off check is almost certainly unnecessary.
*/
if (!(tp->t_flags & TF_MORETOCOME) && /* normal case */
(idle || (tp->t_flags & TF_NODELAY)) &&
len + off >= so->so_snd.ssb_cc &&
!(tp->t_flags & TF_NOPUSH)) {
goto send;
}
if (tp->t_flags & TF_FORCE) /* typ. timeout case */
goto send;
if (len >= tp->max_sndwnd / 2 && tp->max_sndwnd > 0)
goto send;
if (SEQ_LT(tp->snd_nxt, tp->snd_max)) /* retransmit case */
goto send;
if (tp->t_flags & TF_XMITNOW)
goto send;
}
/*
* Compare available window to amount of window
* known to peer (as advertised window less
* next expected input). If the difference is at least two
* max size segments, or at least 50% of the maximum possible
* window, then want to send a window update to peer.
*/
if (recvwin > 0) {
/*
* "adv" is the amount we can increase the window,
* taking into account that we are limited by
* TCP_MAXWIN << tp->rcv_scale.
*/
long adv = min(recvwin, (long)TCP_MAXWIN << tp->rcv_scale) -
(tp->rcv_adv - tp->rcv_nxt);
long hiwat;
/*
* This ack case typically occurs when the user has drained
* the TCP socket buffer sufficiently to warrent an ack
* containing a 'pure window update'... that is, an ack that
* ONLY updates the tcp window.
*
* It is unclear why we would need to do a pure window update
* past 2 segments if we are going to do one at 1/2 the high
* water mark anyway, especially since under normal conditions
* the user program will drain the socket buffer quickly.
* The 2-segment pure window update will often add a large
* number of extra, unnecessary acks to the stream.
*
* avoid_pure_win_update now defaults to 1.
*/
if (avoid_pure_win_update == 0 ||
(tp->t_flags & TF_RXRESIZED)) {
if (adv >= (long) (2 * segsz)) {
goto send;
}
}
hiwat = (long)(TCP_MAXWIN << tp->rcv_scale);
if (hiwat > (long)so->so_rcv.ssb_hiwat)
hiwat = (long)so->so_rcv.ssb_hiwat;
if (adv >= hiwat / 2)
goto send;
}
/*
* Send if we owe the peer an ACK, RST, SYN, or urgent data. ACKNOW
* is also a catch-all for the retransmit timer timeout case.
*/
if (tp->t_flags & TF_ACKNOW)
goto send;
if ((flags & TH_RST) ||
((flags & TH_SYN) && !(tp->t_flags & TF_NEEDSYN)))
goto send;
if (SEQ_GT(tp->snd_up, tp->snd_una))
goto send;
/*
* If our state indicates that FIN should be sent
* and we have not yet done so, then we need to send.
*/
if ((flags & TH_FIN) &&
(!(tp->t_flags & TF_SENTFIN) || tp->snd_nxt == tp->snd_una))
goto send;
/*
* TCP window updates are not reliable, rather a polling protocol
* using ``persist'' packets is used to insure receipt of window
* updates. The three ``states'' for the output side are:
* idle not doing retransmits or persists
* persisting to move a small or zero window
* (re)transmitting and thereby not persisting
*
* tcp_callout_active(tp, tp->tt_persist)
* is true when we are in persist state.
* The TF_FORCE flag in tp->t_flags
* is set when we are called to send a persist packet.
* tcp_callout_active(tp, tp->tt_rexmt)
* is set when we are retransmitting
* The output side is idle when both timers are zero.
*
* If send window is too small, there is data to transmit, and no
* retransmit or persist is pending, then go to persist state.
*
* If nothing happens soon, send when timer expires:
* if window is nonzero, transmit what we can, otherwise force out
* a byte.
*
* Don't try to set the persist state if we are in TCPS_SYN_RECEIVED
* with data pending. This situation can occur during a
* simultanious connect.
*/
if (so->so_snd.ssb_cc > 0 &&
tp->t_state != TCPS_SYN_RECEIVED &&
!tcp_callout_active(tp, tp->tt_rexmt) &&
!tcp_callout_active(tp, tp->tt_persist)) {
tp->t_rxtshift = 0;
tcp_setpersist(tp);
}
/*
* No reason to send a segment, just return.
*/
tp->t_flags &= ~TF_XMITNOW;
return (0);
send:
if (need_sched && len > 0) {
tcp_output_sched(tp);
return 0;
}
/*
* Before ESTABLISHED, force sending of initial options
* unless TCP set not to do any options.
* NOTE: we assume that the IP/TCP header plus TCP options
* always fit in a single mbuf, leaving room for a maximum
* link header, i.e.
* max_linkhdr + sizeof(struct tcpiphdr) + optlen <= MCLBYTES
*/
optlen = 0;
if (isipv6)
hdrlen = sizeof(struct ip6_hdr) + sizeof(struct tcphdr);
else
hdrlen = sizeof(struct tcpiphdr);
if (flags & TH_SYN) {
tp->snd_nxt = tp->iss;
if (!(tp->t_flags & TF_NOOPT)) {
u_short mss;
opt[0] = TCPOPT_MAXSEG;
opt[1] = TCPOLEN_MAXSEG;
mss = htons((u_short) tcp_mssopt(tp));
memcpy(opt + 2, &mss, sizeof mss);
optlen = TCPOLEN_MAXSEG;
if ((tp->t_flags & TF_REQ_SCALE) &&
(!(flags & TH_ACK) ||
(tp->t_flags & TF_RCVD_SCALE))) {
*((u_int32_t *)(opt + optlen)) = htonl(
TCPOPT_NOP << 24 |
TCPOPT_WINDOW << 16 |
TCPOLEN_WINDOW << 8 |
tp->request_r_scale);
optlen += 4;
}
if ((tcp_do_sack && !(flags & TH_ACK)) ||
tp->t_flags & TF_SACK_PERMITTED) {
uint32_t *lp = (uint32_t *)(opt + optlen);
*lp = htonl(TCPOPT_SACK_PERMITTED_ALIGNED);
optlen += TCPOLEN_SACK_PERMITTED_ALIGNED;
}
}
}
/*
* Send a timestamp and echo-reply if this is a SYN and our side
* wants to use timestamps (TF_REQ_TSTMP is set) or both our side
* and our peer have sent timestamps in our SYN's.
*/
if ((tp->t_flags & (TF_REQ_TSTMP | TF_NOOPT)) == TF_REQ_TSTMP &&
!(flags & TH_RST) &&
(!(flags & TH_ACK) || (tp->t_flags & TF_RCVD_TSTMP))) {
u_int32_t *lp = (u_int32_t *)(opt + optlen);
/* Form timestamp option as shown in appendix A of RFC 1323. */
*lp++ = htonl(TCPOPT_TSTAMP_HDR);
*lp++ = htonl(ticks);
*lp = htonl(tp->ts_recent);
optlen += TCPOLEN_TSTAMP_APPA;
}
/* Set receive buffer autosizing timestamp. */
if (tp->rfbuf_ts == 0 && (so->so_rcv.ssb_flags & SSB_AUTOSIZE))
tp->rfbuf_ts = ticks;
/*
* If this is a SACK connection and we have a block to report,
* fill in the SACK blocks in the TCP options.
*/
if (report_sack)
tcp_sack_fill_report(tp, opt, &optlen);
#ifdef TCP_SIGNATURE
if (tp->t_flags & TF_SIGNATURE) {
int i;
u_char *bp;
/*
* Initialize TCP-MD5 option (RFC2385)
*/
bp = (u_char *)opt + optlen;
*bp++ = TCPOPT_SIGNATURE;
*bp++ = TCPOLEN_SIGNATURE;
sigoff = optlen + 2;
for (i = 0; i < TCP_SIGLEN; i++)
*bp++ = 0;
optlen += TCPOLEN_SIGNATURE;
/*
* Terminate options list and maintain 32-bit alignment.
*/
*bp++ = TCPOPT_NOP;
*bp++ = TCPOPT_EOL;
optlen += 2;
}
#endif /* TCP_SIGNATURE */
KASSERT(optlen <= TCP_MAXOLEN, ("too many TCP options"));
hdrlen += optlen;
if (isipv6) {
ipoptlen = ip6_optlen(inp);
} else {
if (inp->inp_options) {
ipoptlen = inp->inp_options->m_len -
offsetof(struct ipoption, ipopt_list);
} else {
int
port_in_use(const char *if_name,
unsigned eport, int proto,
const char *iaddr, unsigned iport)
{
int found = 0;
char ip_addr_str[INET_ADDRSTRLEN];
struct in_addr ip_addr;
#ifdef __linux__
/* linux code */
char line[256];
FILE *f;
const char * tcpfile = "/proc/net/tcp";
const char * udpfile = "/proc/net/udp";
#endif
if(getifaddr(if_name, ip_addr_str, INET_ADDRSTRLEN, &ip_addr, NULL) < 0) {
ip_addr.s_addr = 0;
ip_addr_str[0] = '\0';
}
syslog(LOG_DEBUG, "Check protocol %s for port %u on ext_if %s %s, %08X",
(proto==IPPROTO_TCP)?"tcp":"udp", eport, if_name,
ip_addr_str, (unsigned)ip_addr.s_addr);
/* Phase 1 : check for local sockets (would be listed by netstat) */
#if defined(__linux__)
f = fopen((proto==IPPROTO_TCP)?tcpfile:udpfile, "r");
if (!f) {
syslog(LOG_ERR, "cannot open %s", (proto==IPPROTO_TCP)?tcpfile:udpfile);
return -1;
}
while (fgets(line, 255, f)) {
char eaddr[68];
unsigned tmp_port;
if (sscanf(line, "%*d: %64[0-9A-Fa-f]:%x %*x:%*x %*x %*x:%*x "
"%*x:%*x %*x %*d %*d %*llu",
eaddr, &tmp_port) == 2
) {
/* TODO add IPV6 support if enabled
* Presently assumes IPV4 */
#ifdef DEBUG
syslog(LOG_DEBUG, "port_in_use check port %u and address %s", tmp_port, eaddr);
#endif
if (tmp_port == eport) {
char tmp_addr[4];
struct in_addr *tmp_ip_addr = (struct in_addr *)tmp_addr;
if (sscanf(eaddr,"%2hhx%2hhx%2hhx%2hhx",
&tmp_addr[3],&tmp_addr[2],&tmp_addr[1],&tmp_addr[0]) == 4)
{
if (tmp_ip_addr->s_addr == 0 || tmp_ip_addr->s_addr == ip_addr.s_addr)
{
found++;
break; /* don't care how many, just that we found at least one */
}
}
}
}
}
fclose(f);
#elif defined(__OpenBSD__)
static struct nlist list[] = {
#if 0
{"_tcpstat", 0, 0, 0, 0},
{"_udpstat", 0, 0, 0, 0},
{"_tcbinfo", 0, 0, 0, 0},
{"_udbinfo", 0, 0, 0, 0},
#endif
{"_tcbtable", 0, 0, 0, 0},
{"_udbtable", 0, 0, 0, 0},
{NULL,0, 0, 0, 0}
};
char errstr[_POSIX2_LINE_MAX];
kvm_t *kd;
ssize_t n;
struct inpcbtable table;
struct inpcb *next;
struct inpcb inpcb;
kd = kvm_openfiles(NULL, NULL, NULL, O_RDONLY, errstr);
if(!kd) {
syslog(LOG_ERR, "%s: kvm_openfiles(): %s",
"portinuse()", errstr);
return -1;
}
if(kvm_nlist(kd, list) < 0) {
syslog(LOG_ERR, "%s: kvm_nlist(): %s",
"portinuse()", kvm_geterr(kd));
kvm_close(kd);
return -1;
}
n = kvm_read(kd, list[(proto==IPPROTO_TCP)?0:1].n_value, &table, sizeof(table));
if(n < 0) {
syslog(LOG_ERR, "%s: kvm_read(): %s",
"portinuse()", kvm_geterr(kd));
kvm_close(kd);
return -1;
}
next = CIRCLEQ_FIRST(&table.inpt_queue); /*TAILQ_FIRST(&table.inpt_queue);*/
while(next != NULL) {
if(((u_long)next & 3) != 0) break;
n = kvm_read(kd, (u_long)next, &inpcb, sizeof(inpcb));
if(n < 0) {
syslog(LOG_ERR, "kvm_read(): %s", kvm_geterr(kd));
break;
}
next = CIRCLEQ_NEXT(&inpcb, inp_queue); /*TAILQ_NEXT(&inpcb, inp_queue);*/
/* skip IPv6 sockets */
if((inpcb.inp_flags & INP_IPV6) != 0)
continue;
#ifdef DEBUG
syslog(LOG_DEBUG, "%08lx:%hu %08lx:%hu",
(u_long)inpcb.inp_laddr.s_addr, ntohs(inpcb.inp_lport),
(u_long)inpcb.inp_faddr.s_addr, ntohs(inpcb.inp_fport));
#endif
if(eport == (unsigned)ntohs(inpcb.inp_lport)) {
if(inpcb.inp_laddr.s_addr == INADDR_ANY || inpcb.inp_laddr.s_addr == ip_addr.s_addr) {
found++;
break; /* don't care how many, just that we found at least one */
}
}
}
kvm_close(kd);
#elif defined(__DragonFly__)
const char *varname;
struct xinpcb *xip;
struct xtcpcb *xtp;
struct inpcb *inp;
void *buf = NULL;
void *so_begin, *so_end;
size_t len;
switch (proto) {
case IPPROTO_TCP:
varname = "net.inet.tcp.pcblist";
break;
case IPPROTO_UDP:
varname = "net.inet.udp.pcblist";
break;
default:
syslog(LOG_ERR, "port_in_use() unknown proto=%d", proto);
return -1;
}
if (sysctlbyname(varname, NULL, &len, NULL, 0) < 0) {
syslog(LOG_ERR, "sysctlbyname(%s, NULL, ...): %m", varname);
return -1;
}
buf = malloc(len);
if (buf == NULL) {
syslog(LOG_ERR, "malloc(%u) failed", (unsigned)len);
return -1;
}
if (sysctlbyname(varname, buf, &len, NULL, 0) < 0) {
syslog(LOG_ERR, "sysctlbyname(%s, buf, ...): %m", varname);
free(buf);
return -1;
}
so_begin = buf;
so_end = (uint8_t *)buf + len;
for (so_begin = buf, so_end = (uint8_t *)so_begin + len;
(uint8_t *)so_begin + sizeof(size_t) < (uint8_t *)so_end &&
(uint8_t *)so_begin + *(size_t *)so_begin <= (uint8_t *)so_end;
so_begin = (uint8_t *)so_begin + *(size_t *)so_begin) {
switch (proto) {
case IPPROTO_TCP:
xtp = (struct xtcpcb *)so_begin;
if (xtp->xt_len != sizeof *xtp) {
syslog(LOG_WARNING, "struct xtcpcb size mismatch; %ld vs %ld",
(long)xtp->xt_len, sizeof *xtp);
free(buf);
return -1;
}
inp = &xtp->xt_inp;
break;
case IPPROTO_UDP:
xip = (struct xinpcb *)so_begin;
if (xip->xi_len != sizeof *xip) {
syslog(LOG_WARNING, "struct xinpcb size mismatch : %ld vs %ld",
(long)xip->xi_len, sizeof *xip);
free(buf);
return -1;
}
inp = &xip->xi_inp;
break;
default:
abort();
}
/* no support for IPv6 */
if (INP_ISIPV6(inp) != 0)
continue;
syslog(LOG_DEBUG, "%08lx:%hu %08lx:%hu <=> %hu %08lx:%hu",
(u_long)inp->inp_laddr.s_addr, ntohs(inp->inp_lport),
(u_long)inp->inp_faddr.s_addr, ntohs(inp->inp_fport),
eport, (u_long)ip_addr.s_addr, iport
);
if (eport == (unsigned)ntohs(inp->inp_lport)) {
if (inp->inp_laddr.s_addr == INADDR_ANY || inp->inp_laddr.s_addr == ip_addr.s_addr) {
found++;
break; /* don't care how many, just that we found at least one */
}
}
}
if (buf) {
free(buf);
buf = NULL;
}
#elif defined(__FreeBSD__)
const char *varname;
struct xinpgen *xig, *exig;
struct xinpcb *xip;
struct xtcpcb *xtp;
struct inpcb *inp;
void *buf = NULL;
size_t len;
switch (proto) {
case IPPROTO_TCP:
varname = "net.inet.tcp.pcblist";
break;
case IPPROTO_UDP:
varname = "net.inet.udp.pcblist";
break;
default:
syslog(LOG_ERR, "port_in_use() unknown proto=%d", proto);
return -1;
}
if (sysctlbyname(varname, NULL, &len, NULL, 0) < 0) {
syslog(LOG_ERR, "sysctlbyname(%s, NULL, ...): %m", varname);
return -1;
}
buf = malloc(len);
if (buf == NULL) {
syslog(LOG_ERR, "malloc(%u) failed", (unsigned)len);
return -1;
}
if (sysctlbyname(varname, buf, &len, NULL, 0) < 0) {
syslog(LOG_ERR, "sysctlbyname(%s, buf, ...): %m", varname);
free(buf);
return -1;
}
xig = (struct xinpgen *)buf;
exig = (struct xinpgen *)(void *)((char *)buf + len - sizeof *exig);
if (xig->xig_len != sizeof *xig) {
syslog(LOG_WARNING, "struct xinpgen size mismatch; %ld vs %ld",
(long)xig->xig_len, sizeof *xig);
free(buf);
return -1;
}
if (exig->xig_len != sizeof *exig) {
syslog(LOG_WARNING, "struct xinpgen size mismatch; %ld vs %ld",
(long)exig->xig_len, sizeof *exig);
free(buf);
return -1;
}
while (1) {
xig = (struct xinpgen *)(void *)((char *)xig + xig->xig_len);
if (xig >= exig)
break;
switch (proto) {
case IPPROTO_TCP:
xtp = (struct xtcpcb *)xig;
if (xtp->xt_len != sizeof *xtp) {
syslog(LOG_WARNING, "struct xtcpcb size mismatch; %ld vs %ld",
(long)xtp->xt_len, sizeof *xtp);
free(buf);
return -1;
}
inp = &xtp->xt_inp;
break;
case IPPROTO_UDP:
xip = (struct xinpcb *)xig;
if (xip->xi_len != sizeof *xip) {
syslog(LOG_WARNING, "struct xinpcb size mismatch : %ld vs %ld",
(long)xip->xi_len, sizeof *xip);
free(buf);
return -1;
}
inp = &xip->xi_inp;
break;
default:
abort();
}
/* no support for IPv6 */
if ((inp->inp_vflag & INP_IPV6) != 0)
continue;
syslog(LOG_DEBUG, "%08lx:%hu %08lx:%hu <=> %hu %08lx:%hu",
(u_long)inp->inp_laddr.s_addr, ntohs(inp->inp_lport),
(u_long)inp->inp_faddr.s_addr, ntohs(inp->inp_fport),
eport, (u_long)ip_addr.s_addr, iport
);
if (eport == (unsigned)ntohs(inp->inp_lport)) {
if (inp->inp_laddr.s_addr == INADDR_ANY || inp->inp_laddr.s_addr == ip_addr.s_addr) {
found++;
break; /* don't care how many, just that we found at least one */
}
}
}
if (buf) {
free(buf);
buf = NULL;
}
/* #elif __NetBSD__ */
#else
/* TODO : NetBSD / Darwin (OS X) / Solaris code */
#error "No port_in_use() implementation available for this OS"
#endif
/* Phase 2 : check existing mappings
* TODO : implement for pf/ipfw/etc. */
#if defined(USE_NETFILTER)
if (!found) {
char iaddr_old[16];
unsigned short iport_old;
int i;
for (i = 0; chains_to_check[i]; i++) {
if (get_nat_redirect_rule(chains_to_check[i], if_name, eport, proto,
iaddr_old, sizeof(iaddr_old), &iport_old,
0, 0, 0, 0, 0, 0, 0) == 0)
{
syslog(LOG_DEBUG, "port_in_use check port %d on nat chain %s redirected to %s port %d", eport,
chains_to_check[i], iaddr_old, iport_old);
if (!(strcmp(iaddr, iaddr_old)==0 && iport==iport_old)) {
/* only "in use" if redirected to somewhere else */
found++;
break; /* don't care how many, just that we found at least one */
}
}
}
}
#else /* USE_NETFILTER */
UNUSED(iport); UNUSED(iaddr);
#endif /* USE_NETFILTER */
return found;
}
int
udp6_input(struct mbuf **mp, int *offp, int proto)
{
struct mbuf *m = *mp;
struct ip6_hdr *ip6;
struct udphdr *uh;
struct inpcb *in6p;
struct mbuf *opts = NULL;
int off = *offp;
int plen, ulen;
struct sockaddr_in6 udp_in6;
struct socket *so;
struct inpcbinfo *pcbinfo = &udbinfo[0];
IP6_EXTHDR_CHECK(m, off, sizeof(struct udphdr), IPPROTO_DONE);
ip6 = mtod(m, struct ip6_hdr *);
if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) {
/* XXX send icmp6 host/port unreach? */
m_freem(m);
return IPPROTO_DONE;
}
udp_stat.udps_ipackets++;
plen = ntohs(ip6->ip6_plen) - off + sizeof(*ip6);
uh = (struct udphdr *)((caddr_t)ip6 + off);
ulen = ntohs((u_short)uh->uh_ulen);
if (plen != ulen) {
udp_stat.udps_badlen++;
goto bad;
}
/*
* Checksum extended UDP header and data.
*/
if (uh->uh_sum == 0)
udp_stat.udps_nosum++;
else if (in6_cksum(m, IPPROTO_UDP, off, ulen) != 0) {
udp_stat.udps_badsum++;
goto bad;
}
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
struct inpcb *last, *marker;
/*
* Deliver a multicast datagram to all sockets
* for which the local and remote addresses and ports match
* those of the incoming datagram. This allows more than
* one process to receive multicasts on the same port.
* (This really ought to be done for unicast datagrams as
* well, but that would cause problems with existing
* applications that open both address-specific sockets and
* a wildcard socket listening to the same port -- they would
* end up receiving duplicates of every unicast datagram.
* Those applications open the multiple sockets to overcome an
* inadequacy of the UDP socket interface, but for backwards
* compatibility we avoid the problem here rather than
* fixing the interface. Maybe 4.5BSD will remedy this?)
*/
/*
* In a case that laddr should be set to the link-local
* address (this happens in RIPng), the multicast address
* specified in the received packet does not match with
* laddr. To cure this situation, the matching is relaxed
* if the receiving interface is the same as one specified
* in the socket and if the destination multicast address
* matches one of the multicast groups specified in the socket.
*/
/*
* Construct sockaddr format source address.
*/
init_sin6(&udp_in6, m); /* general init */
udp_in6.sin6_port = uh->uh_sport;
/*
* KAME note: traditionally we dropped udpiphdr from mbuf here.
* We need udphdr for IPsec processing so we do that later.
*/
/*
* Locate pcb(s) for datagram.
* (Algorithm copied from raw_intr().)
*/
last = NULL;
marker = in_pcbmarker(mycpuid);
GET_PCBINFO_TOKEN(pcbinfo);
LIST_INSERT_HEAD(&pcbinfo->pcblisthead, marker, inp_list);
while ((in6p = LIST_NEXT(marker, inp_list)) != NULL) {
LIST_REMOVE(marker, inp_list);
LIST_INSERT_AFTER(in6p, marker, inp_list);
if (in6p->inp_flags & INP_PLACEMARKER)
continue;
if (!INP_ISIPV6(in6p))
continue;
if (in6p->in6p_lport != uh->uh_dport)
continue;
if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr,
&ip6->ip6_dst) &&
!in6_mcmatch(in6p, &ip6->ip6_dst,
m->m_pkthdr.rcvif))
continue;
}
if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr,
&ip6->ip6_src) ||
in6p->in6p_fport != uh->uh_sport)
continue;
}
if (last != NULL) {
struct mbuf *n;
#ifdef IPSEC
/*
* Check AH/ESP integrity.
*/
if (ipsec6_in_reject_so(m, last->inp_socket))
ipsec6stat.in_polvio++;
/* do not inject data into pcb */
else
#endif /* IPSEC */
#ifdef FAST_IPSEC
/*
* Check AH/ESP integrity.
*/
if (ipsec6_in_reject(m, last))
;
else
#endif /* FAST_IPSEC */
if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
/*
* KAME NOTE: do not
* m_copy(m, offset, ...) above.
* ssb_appendaddr() expects M_PKTHDR,
* and m_copy() will copy M_PKTHDR
* only if offset is 0.
*/
so = last->in6p_socket;
if ((last->in6p_flags & IN6P_CONTROLOPTS) ||
(so->so_options & SO_TIMESTAMP)) {
ip6_savecontrol(last, &opts,
ip6, n);
}
m_adj(n, off + sizeof(struct udphdr));
lwkt_gettoken(&so->so_rcv.ssb_token);
if (ssb_appendaddr(&so->so_rcv,
(struct sockaddr *)&udp_in6,
n, opts) == 0) {
m_freem(n);
if (opts)
m_freem(opts);
udp_stat.udps_fullsock++;
} else {
sorwakeup(so);
}
lwkt_reltoken(&so->so_rcv.ssb_token);
opts = NULL;
}
}
last = in6p;
/*
* Don't look for additional matches if this one does
* not have either the SO_REUSEPORT or SO_REUSEADDR
* socket options set. This heuristic avoids searching
* through all pcbs in the common case of a non-shared
* port. It assumes that an application will never
* clear these options after setting them.
*/
if ((last->in6p_socket->so_options &
(SO_REUSEPORT | SO_REUSEADDR)) == 0)
break;
}
LIST_REMOVE(marker, inp_list);
REL_PCBINFO_TOKEN(pcbinfo);
if (last == NULL) {
/*
* No matching pcb found; discard datagram.
* (No need to send an ICMP Port Unreachable
* for a broadcast or multicast datgram.)
*/
udp_stat.udps_noport++;
udp_stat.udps_noportmcast++;
goto bad;
}
#ifdef IPSEC
/*
* Check AH/ESP integrity.
*/
if (ipsec6_in_reject_so(m, last->inp_socket)) {
ipsec6stat.in_polvio++;
goto bad;
}
#endif /* IPSEC */
#ifdef FAST_IPSEC
/*
* Check AH/ESP integrity.
*/
if (ipsec6_in_reject(m, last)) {
goto bad;
}
#endif /* FAST_IPSEC */
if (last->in6p_flags & IN6P_CONTROLOPTS
|| last->in6p_socket->so_options & SO_TIMESTAMP)
ip6_savecontrol(last, &opts, ip6, m);
m_adj(m, off + sizeof(struct udphdr));
so = last->in6p_socket;
lwkt_gettoken(&so->so_rcv.ssb_token);
if (ssb_appendaddr(&so->so_rcv, (struct sockaddr *)&udp_in6,
m, opts) == 0) {
udp_stat.udps_fullsock++;
lwkt_reltoken(&so->so_rcv.ssb_token);
goto bad;
}
sorwakeup(so);
lwkt_reltoken(&so->so_rcv.ssb_token);
return IPPROTO_DONE;
}
/*
* Locate pcb for datagram.
*/
in6p = in6_pcblookup_hash(pcbinfo, &ip6->ip6_src, uh->uh_sport,
&ip6->ip6_dst, uh->uh_dport, 1,
m->m_pkthdr.rcvif);
if (in6p == NULL) {
if (log_in_vain) {
char buf[INET6_ADDRSTRLEN];
strcpy(buf, ip6_sprintf(&ip6->ip6_dst));
log(LOG_INFO,
"Connection attempt to UDP [%s]:%d from [%s]:%d\n",
buf, ntohs(uh->uh_dport),
ip6_sprintf(&ip6->ip6_src), ntohs(uh->uh_sport));
}
udp_stat.udps_noport++;
if (m->m_flags & M_MCAST) {
kprintf("UDP6: M_MCAST is set in a unicast packet.\n");
udp_stat.udps_noportmcast++;
goto bad;
}
icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
return IPPROTO_DONE;
}
#ifdef IPSEC
/*
* Check AH/ESP integrity.
*/
if (ipsec6_in_reject_so(m, in6p->in6p_socket)) {
ipsec6stat.in_polvio++;
goto bad;
}
#endif /* IPSEC */
#ifdef FAST_IPSEC
/*
* Check AH/ESP integrity.
*/
if (ipsec6_in_reject(m, in6p)) {
goto bad;
}
#endif /* FAST_IPSEC */
/*
* Construct sockaddr format source address.
* Stuff source address and datagram in user buffer.
*/
init_sin6(&udp_in6, m); /* general init */
udp_in6.sin6_port = uh->uh_sport;
if (in6p->in6p_flags & IN6P_CONTROLOPTS
|| in6p->in6p_socket->so_options & SO_TIMESTAMP)
ip6_savecontrol(in6p, &opts, ip6, m);
m_adj(m, off + sizeof(struct udphdr));
so = in6p->in6p_socket;
lwkt_gettoken(&so->so_rcv.ssb_token);
if (ssb_appendaddr(&so->so_rcv, (struct sockaddr *)&udp_in6,
m, opts) == 0) {
udp_stat.udps_fullsock++;
lwkt_reltoken(&so->so_rcv.ssb_token);
goto bad;
}
sorwakeup(so);
lwkt_reltoken(&so->so_rcv.ssb_token);
return IPPROTO_DONE;
bad:
if (m)
m_freem(m);
if (opts)
m_freem(opts);
return IPPROTO_DONE;
}
/**
*
* @retval 0 no errors
* @retval !0 errors
*/
static int
_load(netsnmp_container *container, u_int load_flags)
{
size_t len;
int sname[] = { CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_PCBLIST };
char *udpcb_buf = NULL;
#if defined(dragonfly)
struct xinpcb *xig = NULL;
#else
struct xinpgen *xig = NULL;
#endif
netsnmp_udp_endpoint_entry *entry;
int rc = 0;
/*
* Read in the buffer containing the TCP table data
*/
len = 0;
if (sysctl(sname, 4, 0, &len, 0, 0) < 0 ||
(udpcb_buf = malloc(len)) == NULL)
return -1;
if (sysctl(sname, 4, udpcb_buf, &len, 0, 0) < 0) {
free(udpcb_buf);
return -1;
}
/*
* Unpick this into the constituent 'xinpgen' structures, and extract
* the 'inpcb' elements into a linked list (built in reverse)
*/
#if defined(dragonfly)
xig = (struct xinpcb *) udpcb_buf;
#else
xig = (struct xinpgen *) udpcb_buf;
xig = (struct xinpgen *) ((char *) xig + xig->xig_len);
#endif
#if defined(dragonfly)
while (xig && (xig->xi_len >= sizeof(struct xinpcb)))
#else
while (xig && (xig->xig_len > sizeof(struct xinpgen)))
#endif
{
NS_ELEM pcb = *((NS_ELEM *) xig);
#if defined(dragonfly)
xig = (struct xinpcb *) ((char *) xig + xig->xi_len);
#else
xig = (struct xinpgen *) ((char *) xig + xig->xig_len);
#endif
#if !defined(NETSNMP_ENABLE_IPV6)
#ifdef INP_ISIPV6
if (INP_ISIPV6(&pcb.xi_inp))
#else
if (pcb.xi_inp.inp_vflag & INP_IPV6)
#endif
continue;
#endif
entry = netsnmp_access_udp_endpoint_entry_create();
if(NULL == entry) {
rc = -3;
break;
}
/** oddly enough, these appear to already be in network order */
entry->loc_port = htons(pcb.xi_inp.inp_lport);
entry->rmt_port = htons(pcb.xi_inp.inp_fport);
entry->pid = 0;
/** the addr string may need work */
#ifdef INP_ISIPV6
if (INP_ISIPV6(&pcb.xi_inp)) {
#else
if (pcb.xi_inp.inp_vflag & INP_IPV6) {
#endif
entry->loc_addr_len = entry->rmt_addr_len = 16;
memcpy(entry->loc_addr, &pcb.xi_inp.in6p_laddr, 16);
memcpy(entry->rmt_addr, &pcb.xi_inp.in6p_faddr, 16);
}
else {
entry->loc_addr_len = entry->rmt_addr_len = 4;
memcpy(entry->loc_addr, &pcb.xi_inp.inp_laddr, 4);
memcpy(entry->rmt_addr, &pcb.xi_inp.inp_faddr, 4);
}
/*
* add entry to container
*/
entry->index = CONTAINER_SIZE(container) + 1;
CONTAINER_INSERT(container, entry);
}
free(udpcb_buf);
if(rc<0)
return rc;
return 0;
}
