Commit | Line | Data |
---|---|---|
668cc26d | 1 | /* tcp_input.c 1.60 82/03/13 */ |
87e78f19 BJ |
2 | |
3 | #include "../h/param.h" | |
4 | #include "../h/systm.h" | |
dad64fdf | 5 | #include "../h/mbuf.h" |
8a13b737 | 6 | #include "../h/protosw.h" |
dad64fdf | 7 | #include "../h/socket.h" |
d52566dd | 8 | #include "../h/socketvar.h" |
8a13b737 BJ |
9 | #include "../net/in.h" |
10 | #include "../net/in_pcb.h" | |
11 | #include "../net/in_systm.h" | |
12 | #include "../net/if.h" | |
d52566dd | 13 | #include "../net/ip.h" |
eb44bfb2 | 14 | #include "../net/ip_var.h" |
d52566dd BJ |
15 | #include "../net/tcp.h" |
16 | #include "../net/tcp_fsm.h" | |
8a13b737 BJ |
17 | #include "../net/tcp_seq.h" |
18 | #include "../net/tcp_timer.h" | |
d52566dd | 19 | #include "../net/tcp_var.h" |
8a13b737 | 20 | #include "../net/tcpip.h" |
4b935108 | 21 | #include "../net/tcp_debug.h" |
f1b2fa5b | 22 | #include "../errno.h" |
87e78f19 | 23 | |
668cc26d | 24 | #ifdef notdef |
22856bb8 | 25 | int tcpprintfs = 0; |
668cc26d | 26 | #endif |
60b16fa9 | 27 | int tcpcksum = 1; |
4aed14e3 | 28 | struct sockaddr_in tcp_in = { AF_INET }; |
4b935108 | 29 | struct tcpiphdr tcp_saveti; |
8b5a83bb | 30 | extern tcpnodelack; |
87e78f19 | 31 | |
4b935108 | 32 | struct tcpcb *tcp_newtcpcb(); |
2ff61f9d BJ |
33 | /* |
34 | * TCP input routine, follows pages 65-76 of the | |
35 | * protocol specification dated September, 1981 very closely. | |
36 | */ | |
2b4b57cd BJ |
37 | tcp_input(m0) |
38 | struct mbuf *m0; | |
87e78f19 | 39 | { |
2b4b57cd | 40 | register struct tcpiphdr *ti; |
53a5409e | 41 | struct inpcb *inp; |
2b4b57cd | 42 | register struct mbuf *m; |
8b5a83bb | 43 | struct mbuf *om = 0; |
2b4b57cd | 44 | int len, tlen, off; |
8e65fd66 | 45 | register struct tcpcb *tp = 0; |
2b4b57cd | 46 | register int tiflags; |
d52566dd | 47 | struct socket *so; |
f1b2fa5b | 48 | int todrop, acked; |
4b935108 | 49 | short ostate; |
ebcadd38 | 50 | struct in_addr laddr; |
87e78f19 | 51 | |
2b4b57cd | 52 | COUNT(TCP_INPUT); |
87e78f19 | 53 | /* |
4aed14e3 BJ |
54 | * Get IP and TCP header together in first mbuf. |
55 | * Note: IP leaves IP header in first mbuf. | |
87e78f19 | 56 | */ |
2b4b57cd | 57 | m = m0; |
20790db4 | 58 | ti = mtod(m, struct tcpiphdr *); |
4aed14e3 | 59 | if (((struct ip *)ti)->ip_hl > (sizeof (struct ip) >> 2)) |
d63599ac | 60 | ip_stripoptions((struct ip *)ti, (struct mbuf *)0); |
6703c41f BJ |
61 | if (m->m_off > MMAXOFF || m->m_len < sizeof (struct tcpiphdr)) { |
62 | if ((m = m_pullup(m, sizeof (struct tcpiphdr))) == 0) { | |
8a13b737 | 63 | tcpstat.tcps_hdrops++; |
6703c41f | 64 | return; |
8a13b737 BJ |
65 | } |
66 | ti = mtod(m, struct tcpiphdr *); | |
67 | } | |
87e78f19 | 68 | |
2b4b57cd | 69 | /* |
4aed14e3 | 70 | * Checksum extended TCP header and data. |
2b4b57cd BJ |
71 | */ |
72 | tlen = ((struct ip *)ti)->ip_len; | |
73 | len = sizeof (struct ip) + tlen; | |
60b16fa9 | 74 | if (tcpcksum) { |
2b4b57cd BJ |
75 | ti->ti_next = ti->ti_prev = 0; |
76 | ti->ti_x1 = 0; | |
ac83b17a BJ |
77 | ti->ti_len = (u_short)tlen; |
78 | #if vax | |
668cc26d | 79 | ti->ti_len = htons((u_short)ti->ti_len); |
ac83b17a | 80 | #endif |
4b6b94ca | 81 | if (ti->ti_sum = in_cksum(m, len)) { |
2b4b57cd | 82 | tcpstat.tcps_badsum++; |
2ff61f9d | 83 | printf("tcp cksum %x\n", ti->ti_sum); |
8a13b737 | 84 | goto drop; |
87e78f19 BJ |
85 | } |
86 | } | |
87 | ||
88 | /* | |
4aed14e3 | 89 | * Check that TCP offset makes sense, |
8b5a83bb | 90 | * pull out TCP options and adjust length. |
87e78f19 | 91 | */ |
2b4b57cd | 92 | off = ti->ti_off << 2; |
4b6b94ca | 93 | if (off < sizeof (struct tcphdr) || off > tlen) { |
2b4b57cd | 94 | tcpstat.tcps_badoff++; |
8a13b737 | 95 | goto drop; |
2b4b57cd BJ |
96 | } |
97 | ti->ti_len = tlen - off; | |
8b5a83bb BJ |
98 | if (off > sizeof (struct tcphdr)) { |
99 | if ((m = m_pullup(m, sizeof (struct ip) + off)) == 0) { | |
100 | tcpstat.tcps_hdrops++; | |
101 | goto drop; | |
102 | } | |
103 | ti = mtod(m, struct tcpiphdr *); | |
104 | om = m_get(M_DONTWAIT); | |
105 | if (om == 0) | |
106 | goto drop; | |
107 | om->m_off = MMINOFF; | |
108 | om->m_len = off - sizeof (struct tcphdr); | |
109 | { caddr_t op = mtod(m, caddr_t) + sizeof (struct tcpiphdr); | |
668cc26d | 110 | bcopy(op, mtod(om, caddr_t), (unsigned)om->m_len); |
8b5a83bb | 111 | m->m_len -= om->m_len; |
668cc26d SL |
112 | bcopy(op+om->m_len, op, |
113 | (unsigned)(m->m_len-sizeof (struct tcpiphdr))); | |
8b5a83bb BJ |
114 | } |
115 | } | |
2ff61f9d | 116 | tiflags = ti->ti_flags; |
2b4b57cd | 117 | |
795e0416 BJ |
118 | /* |
119 | * drop IP header | |
120 | */ | |
121 | off += sizeof (struct ip); | |
122 | m->m_off += off; | |
123 | m->m_len -= off; | |
124 | ||
4b6b94ca | 125 | #if vax |
8a13b737 | 126 | /* |
4aed14e3 | 127 | * Convert TCP protocol specific fields to host format. |
8a13b737 BJ |
128 | */ |
129 | ti->ti_seq = ntohl(ti->ti_seq); | |
130 | ti->ti_ack = ntohl(ti->ti_ack); | |
131 | ti->ti_win = ntohs(ti->ti_win); | |
132 | ti->ti_urp = ntohs(ti->ti_urp); | |
4b6b94ca | 133 | #endif |
8a13b737 | 134 | |
2b4b57cd | 135 | /* |
1aa87517 BJ |
136 | * Locate pcb for segment. On match, update the local |
137 | * address stored in the block to reflect anchoring. | |
2b4b57cd | 138 | */ |
2ff61f9d | 139 | inp = in_pcblookup |
ebcadd38 BJ |
140 | (&tcb, ti->ti_src, ti->ti_sport, ti->ti_dst, ti->ti_dport, |
141 | INPLOOKUP_WILDCARD); | |
2ff61f9d BJ |
142 | |
143 | /* | |
144 | * If the state is CLOSED (i.e., TCB does not exist) then | |
4aed14e3 | 145 | * all data in the incoming segment is discarded. |
2ff61f9d | 146 | */ |
22856bb8 | 147 | if (inp == 0) |
8a13b737 | 148 | goto dropwithreset; |
2ff61f9d | 149 | tp = intotcpcb(inp); |
22856bb8 | 150 | if (tp == 0) |
8a13b737 | 151 | goto dropwithreset; |
f1b2fa5b | 152 | so = inp->inp_socket; |
4b935108 BJ |
153 | if (so->so_options & SO_DEBUG) { |
154 | ostate = tp->t_state; | |
155 | tcp_saveti = *ti; | |
156 | } | |
87e78f19 | 157 | |
405c9168 BJ |
158 | /* |
159 | * Segment received on connection. | |
160 | * Reset idle time and keep-alive timer. | |
161 | */ | |
162 | tp->t_idle = 0; | |
163 | tp->t_timer[TCPT_KEEP] = TCPTV_KEEP; | |
164 | ||
8b5a83bb BJ |
165 | /* |
166 | * Process options. | |
167 | */ | |
168 | if (om) { | |
169 | tcp_dooptions(tp, om); | |
170 | om = 0; | |
171 | } | |
172 | ||
87e78f19 | 173 | /* |
8a13b737 BJ |
174 | * Calculate amount of space in receive window, |
175 | * and then do TCP input processing. | |
87e78f19 | 176 | */ |
8a13b737 | 177 | tp->rcv_wnd = sbspace(&so->so_rcv); |
4b6b94ca BJ |
178 | if (tp->rcv_wnd < 0) |
179 | tp->rcv_wnd = 0; | |
2ff61f9d | 180 | |
87e78f19 BJ |
181 | switch (tp->t_state) { |
182 | ||
2ff61f9d BJ |
183 | /* |
184 | * If the state is LISTEN then ignore segment if it contains an RST. | |
185 | * If the segment contains an ACK then it is bad and send a RST. | |
186 | * If it does not contain a SYN then it is not interesting; drop it. | |
8a13b737 | 187 | * Otherwise initialize tp->rcv_nxt, and tp->irs, select an initial |
2ff61f9d | 188 | * tp->iss, and send a segment: |
8a13b737 | 189 | * <SEQ=ISS><ACK=RCV_NXT><CTL=SYN,ACK> |
2ff61f9d BJ |
190 | * Also initialize tp->snd_nxt to tp->iss+1 and tp->snd_una to tp->iss. |
191 | * Fill in remote peer address fields if not previously specified. | |
192 | * Enter SYN_RECEIVED state, and process any other fields of this | |
4aed14e3 | 193 | * segment in this state. |
2ff61f9d BJ |
194 | */ |
195 | case TCPS_LISTEN: | |
196 | if (tiflags & TH_RST) | |
197 | goto drop; | |
22856bb8 | 198 | if (tiflags & TH_ACK) |
8a13b737 | 199 | goto dropwithreset; |
22856bb8 | 200 | if ((tiflags & TH_SYN) == 0) |
2ff61f9d | 201 | goto drop; |
4aed14e3 BJ |
202 | tcp_in.sin_addr = ti->ti_src; |
203 | tcp_in.sin_port = ti->ti_sport; | |
ebcadd38 BJ |
204 | laddr = inp->inp_laddr; |
205 | if (inp->inp_laddr.s_addr == 0) | |
206 | inp->inp_laddr = ti->ti_dst; | |
668cc26d | 207 | if (in_pcbconnect(inp, (struct sockaddr_in *)&tcp_in)) { |
ebcadd38 | 208 | inp->inp_laddr = laddr; |
4aed14e3 | 209 | goto drop; |
ebcadd38 | 210 | } |
4aed14e3 BJ |
211 | tp->t_template = tcp_template(tp); |
212 | if (tp->t_template == 0) { | |
213 | in_pcbdisconnect(inp); | |
ebcadd38 | 214 | inp->inp_laddr = laddr; |
4aed14e3 BJ |
215 | goto drop; |
216 | } | |
ebcadd38 | 217 | in_setsockaddr(inp); |
8a13b737 | 218 | tp->iss = tcp_iss; tcp_iss += TCP_ISSINCR/2; |
2ff61f9d | 219 | tp->irs = ti->ti_seq; |
8a13b737 BJ |
220 | tcp_sendseqinit(tp); |
221 | tcp_rcvseqinit(tp); | |
2ff61f9d | 222 | tp->t_state = TCPS_SYN_RECEIVED; |
4aed14e3 | 223 | tp->t_timer[TCPT_KEEP] = TCPTV_KEEP; |
8a13b737 | 224 | goto trimthenstep6; |
87e78f19 | 225 | |
2ff61f9d BJ |
226 | /* |
227 | * If the state is SYN_SENT: | |
228 | * if seg contains an ACK, but not for our SYN, drop the input. | |
229 | * if seg contains a RST, then drop the connection. | |
230 | * if seg does not contain SYN, then drop it. | |
231 | * Otherwise this is an acceptable SYN segment | |
232 | * initialize tp->rcv_nxt and tp->irs | |
233 | * if seg contains ack then advance tp->snd_una | |
234 | * if SYN has been acked change to ESTABLISHED else SYN_RCVD state | |
235 | * arrange for segment to be acked (eventually) | |
236 | * continue processing rest of data/controls, beginning with URG | |
237 | */ | |
238 | case TCPS_SYN_SENT: | |
239 | if ((tiflags & TH_ACK) && | |
22856bb8 BJ |
240 | /* this should be SEQ_LT; is SEQ_LEQ for BBN vax TCP only */ |
241 | (SEQ_LT(ti->ti_ack, tp->iss) || | |
4b6b94ca | 242 | SEQ_GT(ti->ti_ack, tp->snd_max))) |
8a13b737 | 243 | goto dropwithreset; |
2ff61f9d BJ |
244 | if (tiflags & TH_RST) { |
245 | if (tiflags & TH_ACK) | |
4b935108 | 246 | tcp_drop(tp, ECONNREFUSED); |
2ff61f9d | 247 | goto drop; |
87e78f19 | 248 | } |
2ff61f9d BJ |
249 | if ((tiflags & TH_SYN) == 0) |
250 | goto drop; | |
4b6b94ca | 251 | tp->snd_una = ti->ti_ack; |
b8977237 BJ |
252 | if (SEQ_LT(tp->snd_nxt, tp->snd_una)) |
253 | tp->snd_nxt = tp->snd_una; | |
4aed14e3 | 254 | tp->t_timer[TCPT_REXMT] = 0; |
2ff61f9d | 255 | tp->irs = ti->ti_seq; |
8a13b737 BJ |
256 | tcp_rcvseqinit(tp); |
257 | tp->t_flags |= TF_ACKNOW; | |
405c9168 | 258 | if (SEQ_GT(tp->snd_una, tp->iss)) { |
8e65fd66 BJ |
259 | if (so->so_options & SO_ACCEPTCONN) |
260 | so->so_state |= SS_CONNAWAITING; | |
4aed14e3 | 261 | soisconnected(so); |
2ff61f9d | 262 | tp->t_state = TCPS_ESTABLISHED; |
405c9168 BJ |
263 | (void) tcp_reass(tp, (struct tcpiphdr *)0); |
264 | } else | |
8a13b737 BJ |
265 | tp->t_state = TCPS_SYN_RECEIVED; |
266 | goto trimthenstep6; | |
267 | ||
268 | trimthenstep6: | |
269 | /* | |
4b6b94ca | 270 | * Advance ti->ti_seq to correspond to first data byte. |
8a13b737 BJ |
271 | * If data, trim to stay within window, |
272 | * dropping FIN if necessary. | |
273 | */ | |
4b6b94ca | 274 | ti->ti_seq++; |
8a13b737 BJ |
275 | if (ti->ti_len > tp->rcv_wnd) { |
276 | todrop = ti->ti_len - tp->rcv_wnd; | |
277 | m_adj(m, -todrop); | |
278 | ti->ti_len = tp->rcv_wnd; | |
279 | ti->ti_flags &= ~TH_FIN; | |
87e78f19 | 280 | } |
e832edbc | 281 | tp->snd_wl1 = ti->ti_seq - 1; |
8a13b737 | 282 | goto step6; |
2ff61f9d | 283 | } |
87e78f19 | 284 | |
2ff61f9d BJ |
285 | /* |
286 | * States other than LISTEN or SYN_SENT. | |
287 | * First check that at least some bytes of segment are within | |
288 | * receive window. | |
289 | */ | |
290 | if (tp->rcv_wnd == 0) { | |
291 | /* | |
292 | * If window is closed can only take segments at | |
4b6b94ca | 293 | * window edge, and have to drop data and PUSH from |
2ff61f9d BJ |
294 | * incoming segments. |
295 | */ | |
22856bb8 | 296 | if (tp->rcv_nxt != ti->ti_seq) |
2ff61f9d | 297 | goto dropafterack; |
8a13b737 | 298 | if (ti->ti_len > 0) { |
fd5dc5f0 | 299 | m_adj(m, ti->ti_len); |
8a13b737 BJ |
300 | ti->ti_len = 0; |
301 | ti->ti_flags &= ~(TH_PUSH|TH_FIN); | |
87e78f19 | 302 | } |
2ff61f9d BJ |
303 | } else { |
304 | /* | |
4b6b94ca | 305 | * If segment begins before rcv_nxt, drop leading |
2ff61f9d BJ |
306 | * data (and SYN); if nothing left, just ack. |
307 | */ | |
fd5dc5f0 BJ |
308 | todrop = tp->rcv_nxt - ti->ti_seq; |
309 | if (todrop > 0) { | |
8a13b737 | 310 | if (tiflags & TH_SYN) { |
22856bb8 | 311 | tiflags &= ~TH_SYN; |
fd5dc5f0 | 312 | ti->ti_flags &= ~TH_SYN; |
8a13b737 BJ |
313 | ti->ti_seq++; |
314 | if (ti->ti_urp > 1) | |
315 | ti->ti_urp--; | |
316 | else | |
317 | tiflags &= ~TH_URG; | |
318 | todrop--; | |
319 | } | |
22856bb8 | 320 | if (todrop > ti->ti_len) |
2ff61f9d BJ |
321 | goto dropafterack; |
322 | m_adj(m, todrop); | |
323 | ti->ti_seq += todrop; | |
324 | ti->ti_len -= todrop; | |
8a13b737 BJ |
325 | if (ti->ti_urp > todrop) |
326 | ti->ti_urp -= todrop; | |
327 | else { | |
328 | tiflags &= ~TH_URG; | |
fd5dc5f0 BJ |
329 | ti->ti_flags &= ~TH_URG; |
330 | ti->ti_urp = 0; | |
8a13b737 | 331 | } |
2ff61f9d BJ |
332 | } |
333 | /* | |
334 | * If segment ends after window, drop trailing data | |
8a13b737 | 335 | * (and PUSH and FIN); if nothing left, just ACK. |
2ff61f9d | 336 | */ |
fd5dc5f0 BJ |
337 | todrop = (ti->ti_seq+ti->ti_len) - (tp->rcv_nxt+tp->rcv_wnd); |
338 | if (todrop > 0) { | |
22856bb8 | 339 | if (todrop > ti->ti_len) |
2ff61f9d BJ |
340 | goto dropafterack; |
341 | m_adj(m, -todrop); | |
342 | ti->ti_len -= todrop; | |
8a13b737 | 343 | ti->ti_flags &= ~(TH_PUSH|TH_FIN); |
87e78f19 | 344 | } |
87e78f19 | 345 | } |
87e78f19 | 346 | |
dd020fc8 BJ |
347 | /* |
348 | * If a segment is received on a connection after the | |
349 | * user processes are gone, then RST the other end. | |
350 | */ | |
351 | if (so->so_state & SS_USERGONE) { | |
352 | tcp_close(tp); | |
353 | goto dropwithreset; | |
354 | } | |
355 | ||
87e78f19 | 356 | /* |
2ff61f9d BJ |
357 | * If the RST bit is set examine the state: |
358 | * SYN_RECEIVED STATE: | |
359 | * If passive open, return to LISTEN state. | |
360 | * If active open, inform user that connection was refused. | |
361 | * ESTABLISHED, FIN_WAIT_1, FIN_WAIT2, CLOSE_WAIT STATES: | |
362 | * Inform user that connection was reset, and close tcb. | |
363 | * CLOSING, LAST_ACK, TIME_WAIT STATES | |
364 | * Close the tcb. | |
87e78f19 | 365 | */ |
2ff61f9d | 366 | if (tiflags&TH_RST) switch (tp->t_state) { |
4b935108 | 367 | |
2ff61f9d BJ |
368 | case TCPS_SYN_RECEIVED: |
369 | if (inp->inp_socket->so_options & SO_ACCEPTCONN) { | |
4b935108 | 370 | /* a miniature tcp_close, but invisible to user */ |
4aed14e3 | 371 | (void) m_free(dtom(tp->t_template)); |
4b935108 BJ |
372 | (void) m_free(dtom(tp)); |
373 | inp->inp_ppcb = 0; | |
374 | tp = tcp_newtcpcb(inp); | |
375 | tp->t_state = TCPS_LISTEN; | |
ebcadd38 BJ |
376 | inp->inp_faddr.s_addr = 0; |
377 | inp->inp_fport = 0; | |
378 | inp->inp_laddr.s_addr = 0; /* not quite right */ | |
2ff61f9d BJ |
379 | goto drop; |
380 | } | |
8a13b737 | 381 | tcp_drop(tp, ECONNREFUSED); |
2ff61f9d BJ |
382 | goto drop; |
383 | ||
384 | case TCPS_ESTABLISHED: | |
385 | case TCPS_FIN_WAIT_1: | |
386 | case TCPS_FIN_WAIT_2: | |
387 | case TCPS_CLOSE_WAIT: | |
388 | tcp_drop(tp, ECONNRESET); | |
389 | goto drop; | |
390 | ||
391 | case TCPS_CLOSING: | |
392 | case TCPS_LAST_ACK: | |
393 | case TCPS_TIME_WAIT: | |
394 | tcp_close(tp); | |
395 | goto drop; | |
87e78f19 | 396 | } |
87e78f19 BJ |
397 | |
398 | /* | |
2ff61f9d BJ |
399 | * If a SYN is in the window, then this is an |
400 | * error and we send an RST and drop the connection. | |
401 | */ | |
402 | if (tiflags & TH_SYN) { | |
4b6b94ca | 403 | tcp_drop(tp, ECONNRESET); |
8a13b737 | 404 | goto dropwithreset; |
2ff61f9d BJ |
405 | } |
406 | ||
407 | /* | |
408 | * If the ACK bit is off we drop the segment and return. | |
409 | */ | |
8a13b737 | 410 | if ((tiflags & TH_ACK) == 0) |
2ff61f9d BJ |
411 | goto drop; |
412 | ||
413 | /* | |
414 | * Ack processing. | |
87e78f19 | 415 | */ |
87e78f19 BJ |
416 | switch (tp->t_state) { |
417 | ||
2ff61f9d BJ |
418 | /* |
419 | * In SYN_RECEIVED state if the ack ACKs our SYN then enter | |
420 | * ESTABLISHED state and continue processing, othewise | |
421 | * send an RST. | |
422 | */ | |
423 | case TCPS_SYN_RECEIVED: | |
8a13b737 | 424 | if (SEQ_GT(tp->snd_una, ti->ti_ack) || |
4b6b94ca | 425 | SEQ_GT(ti->ti_ack, tp->snd_max)) |
8a13b737 | 426 | goto dropwithreset; |
4aed14e3 | 427 | tp->snd_una++; /* SYN acked */ |
b8977237 BJ |
428 | if (SEQ_LT(tp->snd_nxt, tp->snd_una)) |
429 | tp->snd_nxt = tp->snd_una; | |
4aed14e3 | 430 | tp->t_timer[TCPT_REXMT] = 0; |
8e65fd66 BJ |
431 | if (so->so_options & SO_ACCEPTCONN) |
432 | so->so_state |= SS_CONNAWAITING; | |
8a13b737 BJ |
433 | soisconnected(so); |
434 | tp->t_state = TCPS_ESTABLISHED; | |
405c9168 | 435 | (void) tcp_reass(tp, (struct tcpiphdr *)0); |
4aed14e3 | 436 | tp->snd_wl1 = ti->ti_seq - 1; |
8a13b737 | 437 | /* fall into ... */ |
87e78f19 | 438 | |
2ff61f9d BJ |
439 | /* |
440 | * In ESTABLISHED state: drop duplicate ACKs; ACK out of range | |
441 | * ACKs. If the ack is in the range | |
4b6b94ca | 442 | * tp->snd_una < ti->ti_ack <= tp->snd_max |
2ff61f9d BJ |
443 | * then advance tp->snd_una to ti->ti_ack and drop |
444 | * data from the retransmission queue. If this ACK reflects | |
445 | * more up to date window information we update our window information. | |
446 | */ | |
447 | case TCPS_ESTABLISHED: | |
448 | case TCPS_FIN_WAIT_1: | |
449 | case TCPS_FIN_WAIT_2: | |
450 | case TCPS_CLOSE_WAIT: | |
451 | case TCPS_CLOSING: | |
4aed14e3 BJ |
452 | case TCPS_LAST_ACK: |
453 | case TCPS_TIME_WAIT: | |
8a13b737 BJ |
454 | #define ourfinisacked (acked > 0) |
455 | ||
4aed14e3 | 456 | if (SEQ_LEQ(ti->ti_ack, tp->snd_una)) |
2ff61f9d | 457 | break; |
22856bb8 | 458 | if (SEQ_GT(ti->ti_ack, tp->snd_max)) |
2ff61f9d | 459 | goto dropafterack; |
8a13b737 | 460 | acked = ti->ti_ack - tp->snd_una; |
dd020fc8 BJ |
461 | |
462 | /* | |
463 | * If transmit timer is running and timed sequence | |
464 | * number was acked, update smoothed round trip time. | |
465 | */ | |
466 | if (tp->t_rtt && SEQ_GT(ti->ti_ack, tp->t_rtseq)) { | |
467 | if (tp->t_srtt == 0) | |
468 | tp->t_srtt = tp->t_rtt; | |
469 | else | |
470 | tp->t_srtt = | |
471 | tcp_alpha * tp->t_srtt + | |
472 | (1 - tcp_alpha) * tp->t_rtt; | |
473 | /* printf("rtt %d srtt*100 now %d\n", tp->t_rtt, (int)(tp->t_srtt*100)); */ | |
474 | tp->t_rtt = 0; | |
475 | } | |
476 | ||
6703c41f | 477 | if (ti->ti_ack == tp->snd_max) |
4aed14e3 | 478 | tp->t_timer[TCPT_REXMT] = 0; |
6703c41f | 479 | else { |
4aed14e3 BJ |
480 | TCPT_RANGESET(tp->t_timer[TCPT_REXMT], |
481 | tcp_beta * tp->t_srtt, TCPTV_MIN, TCPTV_MAX); | |
dd020fc8 | 482 | tp->t_rtt = 1; |
22856bb8 | 483 | tp->t_rxtshift = 0; |
8a13b737 | 484 | } |
6703c41f BJ |
485 | if (acked > so->so_snd.sb_cc) { |
486 | sbdrop(&so->so_snd, so->so_snd.sb_cc); | |
487 | tp->snd_wnd -= so->so_snd.sb_cc; | |
488 | } else { | |
668cc26d | 489 | sbdrop(&so->so_snd, acked); |
6703c41f BJ |
490 | tp->snd_wnd -= acked; |
491 | acked = 0; | |
492 | } | |
22856bb8 BJ |
493 | if (so->so_snd.sb_flags & SB_WAIT) |
494 | sowwakeup(so); | |
4b6b94ca | 495 | tp->snd_una = ti->ti_ack; |
b8977237 BJ |
496 | if (SEQ_LT(tp->snd_nxt, tp->snd_una)) |
497 | tp->snd_nxt = tp->snd_una; | |
405c9168 | 498 | |
87e78f19 BJ |
499 | switch (tp->t_state) { |
500 | ||
2ff61f9d BJ |
501 | /* |
502 | * In FIN_WAIT_1 STATE in addition to the processing | |
503 | * for the ESTABLISHED state if our FIN is now acknowledged | |
8a13b737 | 504 | * then enter FIN_WAIT_2. |
2ff61f9d BJ |
505 | */ |
506 | case TCPS_FIN_WAIT_1: | |
fdae4427 BJ |
507 | if (ourfinisacked) { |
508 | /* | |
509 | * If we can't receive any more | |
510 | * data, then closing user can proceed. | |
511 | */ | |
512 | if (so->so_state & SS_CANTRCVMORE) | |
513 | soisdisconnected(so); | |
8a13b737 | 514 | tp->t_state = TCPS_FIN_WAIT_2; |
fdae4427 | 515 | } |
87e78f19 BJ |
516 | break; |
517 | ||
2ff61f9d BJ |
518 | /* |
519 | * In CLOSING STATE in addition to the processing for | |
520 | * the ESTABLISHED state if the ACK acknowledges our FIN | |
521 | * then enter the TIME-WAIT state, otherwise ignore | |
522 | * the segment. | |
523 | */ | |
524 | case TCPS_CLOSING: | |
4aed14e3 | 525 | if (ourfinisacked) { |
2ff61f9d | 526 | tp->t_state = TCPS_TIME_WAIT; |
4aed14e3 BJ |
527 | tcp_canceltimers(tp); |
528 | tp->t_timer[TCPT_2MSL] = 2 * TCPTV_MSL; | |
529 | soisdisconnected(so); | |
530 | } | |
531 | break; | |
87e78f19 | 532 | |
2ff61f9d | 533 | /* |
8a13b737 BJ |
534 | * The only thing that can arrive in LAST_ACK state |
535 | * is an acknowledgment of our FIN. If our FIN is now | |
536 | * acknowledged, delete the TCB, enter the closed state | |
537 | * and return. | |
2ff61f9d BJ |
538 | */ |
539 | case TCPS_LAST_ACK: | |
be43ac7f | 540 | if (ourfinisacked) |
2ff61f9d BJ |
541 | tcp_close(tp); |
542 | goto drop; | |
87e78f19 | 543 | |
2ff61f9d BJ |
544 | /* |
545 | * In TIME_WAIT state the only thing that should arrive | |
546 | * is a retransmission of the remote FIN. Acknowledge | |
547 | * it and restart the finack timer. | |
548 | */ | |
549 | case TCPS_TIME_WAIT: | |
405c9168 | 550 | tp->t_timer[TCPT_2MSL] = 2 * TCPTV_MSL; |
2ff61f9d | 551 | goto dropafterack; |
87e78f19 | 552 | } |
8a13b737 BJ |
553 | #undef ourfinisacked |
554 | } | |
87e78f19 | 555 | |
2ff61f9d | 556 | step6: |
4aed14e3 BJ |
557 | /* |
558 | * Update window information. | |
559 | */ | |
22856bb8 | 560 | if (SEQ_LT(tp->snd_wl1, ti->ti_seq) || tp->snd_wl1 == ti->ti_seq && |
8e65fd66 | 561 | (SEQ_LT(tp->snd_wl2, ti->ti_ack) || |
22856bb8 | 562 | tp->snd_wl2 == ti->ti_ack && ti->ti_win > tp->snd_wnd)) { |
4aed14e3 BJ |
563 | tp->snd_wnd = ti->ti_win; |
564 | tp->snd_wl1 = ti->ti_seq; | |
565 | tp->snd_wl2 = ti->ti_ack; | |
566 | if (tp->snd_wnd > 0) | |
567 | tp->t_timer[TCPT_PERSIST] = 0; | |
568 | } | |
4aed14e3 | 569 | |
2ff61f9d | 570 | /* |
b2db9217 | 571 | * Process segments with URG. |
2ff61f9d | 572 | */ |
b2db9217 BJ |
573 | if ((tiflags & TH_URG) && TCPS_HAVERCVDFIN(tp->t_state) == 0) { |
574 | /* | |
575 | * If this segment advances the known urgent pointer, | |
576 | * then mark the data stream. This should not happen | |
577 | * in CLOSE_WAIT, CLOSING, LAST_ACK or TIME_WAIT STATES since | |
578 | * a FIN has been received from the remote side. | |
579 | * In these states we ignore the URG. | |
580 | */ | |
581 | if (SEQ_GT(ti->ti_seq+ti->ti_urp, tp->rcv_up)) { | |
582 | tp->rcv_up = ti->ti_seq + ti->ti_urp; | |
583 | so->so_oobmark = so->so_rcv.sb_cc + | |
584 | (tp->rcv_up - tp->rcv_nxt) - 1; | |
585 | if (so->so_oobmark == 0) | |
586 | so->so_state |= SS_RCVATMARK; | |
8b5a83bb | 587 | #ifdef TCPTRUEOOB |
b2db9217 | 588 | if ((tp->t_flags & TF_DOOOB) == 0) |
8b5a83bb | 589 | #endif |
b2db9217 BJ |
590 | sohasoutofband(so); |
591 | tp->t_oobflags &= ~TCPOOB_HAVEDATA; | |
592 | } | |
593 | /* | |
594 | * Remove out of band data so doesn't get presented to user. | |
595 | * This can happen independent of advancing the URG pointer, | |
596 | * but if two URG's are pending at once, some out-of-band | |
597 | * data may creep in... ick. | |
598 | */ | |
599 | if (ti->ti_urp <= ti->ti_len) { | |
600 | tcp_pulloutofband(so, ti); | |
8b5a83bb | 601 | } |
5e74df82 | 602 | } |
87e78f19 BJ |
603 | |
604 | /* | |
2ff61f9d BJ |
605 | * Process the segment text, merging it into the TCP sequencing queue, |
606 | * and arranging for acknowledgment of receipt if necessary. | |
607 | * This process logically involves adjusting tp->rcv_wnd as data | |
608 | * is presented to the user (this happens in tcp_usrreq.c, | |
609 | * case PRU_RCVD). If a FIN has already been received on this | |
610 | * connection then we just ignore the text. | |
87e78f19 | 611 | */ |
e832edbc BJ |
612 | if ((ti->ti_len || (tiflags&TH_FIN)) && |
613 | TCPS_HAVERCVDFIN(tp->t_state) == 0) { | |
2ff61f9d | 614 | tiflags = tcp_reass(tp, ti); |
8b5a83bb BJ |
615 | if (tcpnodelack == 0) |
616 | tp->t_flags |= TF_DELACK; | |
617 | else | |
618 | tp->t_flags |= TF_ACKNOW; | |
4aed14e3 | 619 | } else { |
2b4b57cd | 620 | m_freem(m); |
e832edbc | 621 | tiflags &= ~TH_FIN; |
4aed14e3 | 622 | } |
87e78f19 BJ |
623 | |
624 | /* | |
e832edbc BJ |
625 | * If FIN is received ACK the FIN and let the user know |
626 | * that the connection is closing. | |
87e78f19 | 627 | */ |
e832edbc | 628 | if (tiflags & TH_FIN) { |
4aed14e3 BJ |
629 | if (TCPS_HAVERCVDFIN(tp->t_state) == 0) { |
630 | socantrcvmore(so); | |
631 | tp->t_flags |= TF_ACKNOW; | |
632 | tp->rcv_nxt++; | |
633 | } | |
2ff61f9d | 634 | switch (tp->t_state) { |
87e78f19 | 635 | |
2ff61f9d BJ |
636 | /* |
637 | * In SYN_RECEIVED and ESTABLISHED STATES | |
638 | * enter the CLOSE_WAIT state. | |
53a5409e | 639 | */ |
2ff61f9d BJ |
640 | case TCPS_SYN_RECEIVED: |
641 | case TCPS_ESTABLISHED: | |
642 | tp->t_state = TCPS_CLOSE_WAIT; | |
643 | break; | |
53a5409e | 644 | |
2ff61f9d | 645 | /* |
8a13b737 BJ |
646 | * If still in FIN_WAIT_1 STATE FIN has not been acked so |
647 | * enter the CLOSING state. | |
53a5409e | 648 | */ |
2ff61f9d | 649 | case TCPS_FIN_WAIT_1: |
8a13b737 | 650 | tp->t_state = TCPS_CLOSING; |
2ff61f9d | 651 | break; |
87e78f19 | 652 | |
2ff61f9d BJ |
653 | /* |
654 | * In FIN_WAIT_2 state enter the TIME_WAIT state, | |
655 | * starting the time-wait timer, turning off the other | |
656 | * standard timers. | |
657 | */ | |
658 | case TCPS_FIN_WAIT_2: | |
4aed14e3 | 659 | tp->t_state = TCPS_TIME_WAIT; |
a6503abf | 660 | tcp_canceltimers(tp); |
405c9168 | 661 | tp->t_timer[TCPT_2MSL] = 2 * TCPTV_MSL; |
4aed14e3 | 662 | soisdisconnected(so); |
2ff61f9d BJ |
663 | break; |
664 | ||
53a5409e | 665 | /* |
2ff61f9d | 666 | * In TIME_WAIT state restart the 2 MSL time_wait timer. |
53a5409e | 667 | */ |
2ff61f9d | 668 | case TCPS_TIME_WAIT: |
405c9168 | 669 | tp->t_timer[TCPT_2MSL] = 2 * TCPTV_MSL; |
2ff61f9d | 670 | break; |
8a13b737 | 671 | } |
87e78f19 | 672 | } |
4b935108 BJ |
673 | if (so->so_options & SO_DEBUG) |
674 | tcp_trace(TA_INPUT, ostate, tp, &tcp_saveti, 0); | |
8a13b737 BJ |
675 | |
676 | /* | |
677 | * Return any desired output. | |
678 | */ | |
668cc26d | 679 | (void) tcp_output(tp); |
2ff61f9d | 680 | return; |
8a13b737 | 681 | |
2ff61f9d | 682 | dropafterack: |
8a13b737 | 683 | /* |
4aed14e3 | 684 | * Generate an ACK dropping incoming segment. |
8a13b737 BJ |
685 | * Make ACK reflect our state. |
686 | */ | |
687 | if (tiflags & TH_RST) | |
688 | goto drop; | |
8e65fd66 | 689 | tcp_respond(tp, ti, tp->rcv_nxt, tp->snd_nxt, TH_ACK); |
4b6b94ca | 690 | return; |
8a13b737 BJ |
691 | |
692 | dropwithreset: | |
8b5a83bb | 693 | if (om) |
668cc26d | 694 | (void) m_free(om); |
8a13b737 | 695 | /* |
4aed14e3 | 696 | * Generate a RST, dropping incoming segment. |
8a13b737 BJ |
697 | * Make ACK acceptable to originator of segment. |
698 | */ | |
699 | if (tiflags & TH_RST) | |
700 | goto drop; | |
701 | if (tiflags & TH_ACK) | |
8e65fd66 | 702 | tcp_respond(tp, ti, (tcp_seq)0, ti->ti_ack, TH_RST); |
8a13b737 BJ |
703 | else { |
704 | if (tiflags & TH_SYN) | |
705 | ti->ti_len++; | |
8e65fd66 | 706 | tcp_respond(tp, ti, ti->ti_seq+ti->ti_len, (tcp_seq)0, TH_RST|TH_ACK); |
8a13b737 | 707 | } |
4b6b94ca | 708 | return; |
8a13b737 | 709 | |
2ff61f9d | 710 | drop: |
8a13b737 BJ |
711 | /* |
712 | * Drop space held by incoming segment and return. | |
713 | */ | |
2ff61f9d | 714 | m_freem(m); |
4b935108 | 715 | return; |
2ff61f9d BJ |
716 | } |
717 | ||
8b5a83bb BJ |
718 | tcp_dooptions(tp, om) |
719 | struct tcpcb *tp; | |
720 | struct mbuf *om; | |
5e74df82 | 721 | { |
8b5a83bb BJ |
722 | register u_char *cp; |
723 | int opt, optlen, cnt; | |
724 | ||
725 | cp = mtod(om, u_char *); | |
726 | cnt = om->m_len; | |
727 | for (; cnt > 0; cnt -= optlen, cp += optlen) { | |
728 | opt = cp[0]; | |
729 | if (opt == TCPOPT_EOL) | |
730 | break; | |
731 | if (opt == TCPOPT_NOP) | |
732 | optlen = 1; | |
733 | else | |
734 | optlen = cp[1]; | |
735 | switch (opt) { | |
736 | ||
737 | default: | |
738 | break; | |
739 | ||
740 | case TCPOPT_MAXSEG: | |
741 | if (optlen != 4) | |
742 | continue; | |
743 | tp->t_maxseg = *(u_short *)(cp + 2); | |
744 | #if vax | |
668cc26d | 745 | tp->t_maxseg = ntohs((u_short)tp->t_maxseg); |
8b5a83bb BJ |
746 | #endif |
747 | break; | |
748 | ||
749 | #ifdef TCPTRUEOOB | |
750 | case TCPOPT_WILLOOB: | |
751 | tp->t_flags |= TF_DOOOB; | |
752 | printf("tp %x dooob\n", tp); | |
753 | break; | |
754 | ||
755 | case TCPOPT_OOBDATA: { | |
756 | int seq; | |
b2db9217 BJ |
757 | register struct socket *so = tp->t_inpcb->inp_socket; |
758 | tcp_seq mark; | |
8b5a83bb | 759 | |
b2db9217 | 760 | if (optlen != 8) |
8b5a83bb BJ |
761 | continue; |
762 | seq = cp[2]; | |
763 | if (seq < tp->t_iobseq) | |
764 | seq += 256; | |
765 | printf("oobdata cp[2] %d iobseq %d seq %d\n", cp[2], tp->t_iobseq, seq); | |
766 | if (seq - tp->t_iobseq > 128) { | |
767 | printf("bad seq\n"); | |
768 | tp->t_oobflags |= TCPOOB_OWEACK; | |
769 | break; | |
770 | } | |
771 | tp->t_iobseq = cp[2]; | |
772 | tp->t_iobc = cp[3]; | |
b2db9217 BJ |
773 | mark = *(tcp_seq *)(cp + 4); |
774 | #if vax | |
775 | mark = ntohl(mark); | |
776 | #endif | |
777 | so->so_oobmark = so->so_rcv.sb_cc + (mark-tp->rcv_nxt); | |
778 | if (so->so_oobmark == 0) | |
779 | so->so_state |= SS_RCVATMARK; | |
8b5a83bb | 780 | printf("take oob data %x input iobseq now %x\n", tp->t_iobc, tp->t_iobseq); |
b2db9217 | 781 | sohasoutofband(so); |
8b5a83bb | 782 | break; |
5e74df82 | 783 | } |
8b5a83bb BJ |
784 | |
785 | case TCPOPT_OOBACK: { | |
786 | int seq; | |
787 | ||
788 | if (optlen != 4) | |
789 | continue; | |
790 | if (tp->t_oobseq != cp[2]) { | |
791 | printf("wrong ack\n"); | |
792 | break; | |
793 | } | |
794 | printf("take oob ack %x and cancel rexmt\n", cp[2]); | |
795 | tp->t_oobflags &= ~TCPOOB_NEEDACK; | |
796 | tp->t_timer[TCPT_OOBREXMT] = 0; | |
5e74df82 | 797 | break; |
8b5a83bb BJ |
798 | } |
799 | #endif TCPTRUEOOB | |
800 | } | |
5e74df82 | 801 | } |
668cc26d | 802 | (void) m_free(om); |
5e74df82 BJ |
803 | } |
804 | ||
b2db9217 BJ |
805 | /* |
806 | * Pull out of band byte out of a segment so | |
807 | * it doesn't appear in the user's data queue. | |
808 | * It is still reflected in the segment length for | |
809 | * sequencing purposes. | |
810 | */ | |
811 | tcp_pulloutofband(so, ti) | |
812 | struct socket *so; | |
813 | struct tcpiphdr *ti; | |
814 | { | |
815 | register struct mbuf *m; | |
1acff8ec | 816 | int cnt = ti->ti_urp - 1; |
b2db9217 BJ |
817 | |
818 | m = dtom(ti); | |
819 | while (cnt >= 0) { | |
820 | if (m->m_len > cnt) { | |
821 | char *cp = mtod(m, caddr_t) + cnt; | |
822 | struct tcpcb *tp = sototcpcb(so); | |
823 | ||
824 | tp->t_iobc = *cp; | |
825 | tp->t_oobflags |= TCPOOB_HAVEDATA; | |
668cc26d | 826 | bcopy(cp+1, cp, (unsigned)(m->m_len - cnt - 1)); |
b2db9217 BJ |
827 | m->m_len--; |
828 | return; | |
829 | } | |
830 | cnt -= m->m_len; | |
831 | m = m->m_next; | |
832 | if (m == 0) | |
833 | break; | |
834 | } | |
835 | panic("tcp_pulloutofband"); | |
836 | } | |
837 | ||
2ff61f9d BJ |
838 | /* |
839 | * Insert segment ti into reassembly queue of tcp with | |
840 | * control block tp. Return TH_FIN if reassembly now includes | |
841 | * a segment with FIN. | |
842 | */ | |
f1b2fa5b | 843 | tcp_reass(tp, ti) |
2ff61f9d BJ |
844 | register struct tcpcb *tp; |
845 | register struct tcpiphdr *ti; | |
2ff61f9d BJ |
846 | { |
847 | register struct tcpiphdr *q; | |
8a13b737 | 848 | struct socket *so = tp->t_inpcb->inp_socket; |
e832edbc BJ |
849 | struct mbuf *m; |
850 | int flags; | |
8a13b737 | 851 | COUNT(TCP_REASS); |
2ff61f9d BJ |
852 | |
853 | /* | |
405c9168 BJ |
854 | * Call with ti==0 after become established to |
855 | * force pre-ESTABLISHED data up to user socket. | |
2ff61f9d | 856 | */ |
405c9168 | 857 | if (ti == 0) |
2ff61f9d | 858 | goto present; |
87e78f19 | 859 | |
2ff61f9d BJ |
860 | /* |
861 | * Find a segment which begins after this one does. | |
862 | */ | |
863 | for (q = tp->seg_next; q != (struct tcpiphdr *)tp; | |
864 | q = (struct tcpiphdr *)q->ti_next) | |
865 | if (SEQ_GT(q->ti_seq, ti->ti_seq)) | |
866 | break; | |
867 | ||
868 | /* | |
869 | * If there is a preceding segment, it may provide some of | |
870 | * our data already. If so, drop the data from the incoming | |
871 | * segment. If it provides all of our data, drop us. | |
872 | */ | |
873 | if ((struct tcpiphdr *)q->ti_prev != (struct tcpiphdr *)tp) { | |
874 | register int i; | |
fd5dc5f0 | 875 | q = (struct tcpiphdr *)q->ti_prev; |
2ff61f9d BJ |
876 | /* conversion to int (in i) handles seq wraparound */ |
877 | i = q->ti_seq + q->ti_len - ti->ti_seq; | |
878 | if (i > 0) { | |
2b4b57cd | 879 | if (i >= ti->ti_len) |
2ff61f9d BJ |
880 | goto drop; |
881 | m_adj(dtom(tp), i); | |
2b4b57cd | 882 | ti->ti_len -= i; |
2ff61f9d | 883 | ti->ti_seq += i; |
53a5409e | 884 | } |
2ff61f9d BJ |
885 | q = (struct tcpiphdr *)(q->ti_next); |
886 | } | |
87e78f19 | 887 | |
2ff61f9d BJ |
888 | /* |
889 | * While we overlap succeeding segments trim them or, | |
890 | * if they are completely covered, dequeue them. | |
891 | */ | |
fd5dc5f0 | 892 | while (q != (struct tcpiphdr *)tp) { |
2ff61f9d | 893 | register int i = (ti->ti_seq + ti->ti_len) - q->ti_seq; |
fd5dc5f0 BJ |
894 | if (i <= 0) |
895 | break; | |
2ff61f9d | 896 | if (i < q->ti_len) { |
fd5dc5f0 | 897 | q->ti_seq += i; |
2ff61f9d BJ |
898 | q->ti_len -= i; |
899 | m_adj(dtom(q), i); | |
900 | break; | |
ac5e71a1 | 901 | } |
2ff61f9d | 902 | q = (struct tcpiphdr *)q->ti_next; |
473a17a5 | 903 | m = dtom(q->ti_prev); |
2ff61f9d | 904 | remque(q->ti_prev); |
473a17a5 | 905 | m_freem(m); |
2ff61f9d | 906 | } |
87e78f19 | 907 | |
2ff61f9d BJ |
908 | /* |
909 | * Stick new segment in its place. | |
910 | */ | |
911 | insque(ti, q->ti_prev); | |
2ff61f9d | 912 | |
2ff61f9d BJ |
913 | present: |
914 | /* | |
4aed14e3 BJ |
915 | * Present data to user, advancing rcv_nxt through |
916 | * completed sequence space. | |
2ff61f9d | 917 | */ |
e832edbc | 918 | if (TCPS_HAVERCVDSYN(tp->t_state) == 0) |
4aed14e3 | 919 | return (0); |
2b4b57cd | 920 | ti = tp->seg_next; |
e832edbc BJ |
921 | if (ti == (struct tcpiphdr *)tp || ti->ti_seq != tp->rcv_nxt) |
922 | return (0); | |
923 | if (tp->t_state == TCPS_SYN_RECEIVED && ti->ti_len) | |
924 | return (0); | |
925 | do { | |
4aed14e3 BJ |
926 | tp->rcv_nxt += ti->ti_len; |
927 | flags = ti->ti_flags & TH_FIN; | |
2b4b57cd | 928 | remque(ti); |
e832edbc | 929 | m = dtom(ti); |
2b4b57cd | 930 | ti = (struct tcpiphdr *)ti->ti_next; |
e832edbc | 931 | if (so->so_state & SS_CANTRCVMORE) |
668cc26d | 932 | m_freem(m); |
e832edbc BJ |
933 | else |
934 | sbappend(&so->so_rcv, m); | |
935 | } while (ti != (struct tcpiphdr *)tp && ti->ti_seq == tp->rcv_nxt); | |
936 | sorwakeup(so); | |
2ff61f9d BJ |
937 | return (flags); |
938 | drop: | |
939 | m_freem(dtom(ti)); | |
e832edbc | 940 | return (0); |
d52566dd | 941 | } |