X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/cf7d32b81c573a0536dc4da4157f9c26f8d0bed3..b0d623f7f2ae71ed96e60569f61f9a9a27016e80:/bsd/netinet/tcp_output.c?ds=sidebyside diff --git a/bsd/netinet/tcp_output.c b/bsd/netinet/tcp_output.c index ca32f6b40..9d37f63fd 100644 --- a/bsd/netinet/tcp_output.c +++ b/bsd/netinet/tcp_output.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2000-2007 Apple Inc. All rights reserved. + * Copyright (c) 2000-2008 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * @@ -139,6 +139,11 @@ int tcp_do_newreno = 0; SYSCTL_INT(_net_inet_tcp, OID_AUTO, newreno, CTLFLAG_RW, &tcp_do_newreno, 0, "Enable NewReno Algorithms"); +int tcp_do_tso = 1; +SYSCTL_INT(_net_inet_tcp, OID_AUTO, tso, CTLFLAG_RW, + &tcp_do_tso, 0, "Enable TCP Segmentation Offload"); + + int tcp_ecn_outbound = 0; SYSCTL_INT(_net_inet_tcp, OID_AUTO, ecn_initiate_out, CTLFLAG_RW, &tcp_ecn_outbound, 0, "Initiate ECN for outbound connections"); @@ -155,10 +160,9 @@ int tcp_output_unlocked = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, socket_unlocked_on_output, CTLFLAG_RW, &tcp_output_unlocked, 0, "Unlock TCP when sending packets down to IP"); -static long packchain_newlist = 0; -static long packchain_looped = 0; -static long packchain_sent = 0; - +static int32_t packchain_newlist = 0; +static int32_t packchain_looped = 0; +static int32_t packchain_sent = 0; /* temporary: for testing */ #if IPSEC @@ -166,16 +170,20 @@ extern int ipsec_bypass; #endif extern int slowlink_wsize; /* window correction for slow links */ -extern u_long route_generation; #if IPFIREWALL extern int fw_enable; /* firewall check for packet chaining */ extern int fw_bypass; /* firewall check: disable packet chaining if there is rules */ #endif /* IPFIREWALL */ extern vm_size_t so_cache_zone_element_size; +#if RANDOM_IP_ID +extern int ip_use_randomid; +#endif /* RANDOM_IP_ID */ +extern u_int32_t dlil_filter_count; +extern u_int32_t kipf_count; static int tcp_ip_output(struct socket *, struct tcpcb *, struct mbuf *, int, - struct mbuf *, int); + struct mbuf *, int, int); static __inline__ u_int16_t get_socket_id(struct socket * s) @@ -185,7 +193,7 @@ get_socket_id(struct socket * s) if (so_cache_zone_element_size == 0) { return (0); } - val = (u_int16_t)(((u_int32_t)s) / so_cache_zone_element_size); + val = (u_int16_t)(((uintptr_t)s) / so_cache_zone_element_size); if (val == 0) { val = 0xffff; } @@ -215,8 +223,8 @@ int tcp_output(struct tcpcb *tp) { struct socket *so = tp->t_inpcb->inp_socket; - long len, recwin, sendwin; - int off, flags, error; + int32_t len, recwin, sendwin, off; + int flags, error; register struct mbuf *m; struct ip *ip = NULL; register struct ipovly *ipov = NULL; @@ -228,9 +236,12 @@ tcp_output(struct tcpcb *tp) unsigned ipoptlen, optlen, hdrlen; int idle, sendalot, lost = 0; int i, sack_rxmit; + int tso = 0; int sack_bytes_rxmt; struct sackhole *p; - +#ifdef IPSEC + unsigned ipsec_optlen = 0; +#endif int maxburst = TCP_MAXBURST; int last_off = 0; int m_off; @@ -312,14 +323,19 @@ again: * come back before the TCP connection times out). */ rt = tp->t_inpcb->inp_route.ro_rt; - if (rt != NULL && rt->generation_id != route_generation) { + if (rt != NULL && (!(rt->rt_flags & RTF_UP) || + rt->generation_id != route_generation)) { struct ifnet *ifp; + struct in_ifaddr *ia; /* disable multipages at the socket */ somultipages(so, FALSE); + /* Disable TSO for the socket until we know more */ + tp->t_flags &= ~TF_TSO; + /* check that the source address is still valid */ - if (ifa_foraddr(tp->t_inpcb->inp_laddr.s_addr) == 0) { + if ((ia = ifa_foraddr(tp->t_inpcb->inp_laddr.s_addr)) == NULL) { if (tp->t_state >= TCPS_CLOSE_WAIT) { tcp_drop(tp, EADDRNOTAVAIL); @@ -351,16 +367,18 @@ again: else return(0); /* silently ignore, keep data in socket: address may be back */ } + ifafree(&ia->ia_ifa); /* * Address is still valid; check for multipages capability * again in case the outgoing interface has changed. */ - lck_mtx_lock(rt_mtx); - rt = tp->t_inpcb->inp_route.ro_rt; - if (rt != NULL && (ifp = rt->rt_ifp) != NULL) + RT_LOCK(rt); + if ((ifp = rt->rt_ifp) != NULL) { somultipages(so, (ifp->if_hwassist & IFNET_MULTIPAGES)); - if (rt != NULL && rt->generation_id != route_generation) + tcp_set_tso(tp, ifp); + } + if (rt->rt_flags & RTF_UP) rt->generation_id = route_generation; /* * See if we should do MTU discovery. Don't do it if: @@ -376,7 +394,7 @@ again: else tp->t_flags |= TF_PMTUD; - lck_mtx_unlock(rt_mtx); + RT_UNLOCK(rt); } } @@ -411,7 +429,7 @@ again: p = NULL; if (tp->sack_enable && IN_FASTRECOVERY(tp) && (p = tcp_sack_output(tp, &sack_bytes_rxmt))) { - long cwin; + int32_t cwin; cwin = min(tp->snd_wnd, tp->snd_cwnd) - sack_bytes_rxmt; if (cwin < 0) @@ -434,18 +452,20 @@ again: goto after_sack_rexmit; } else /* Can rexmit part of the current hole */ - len = ((long)ulmin(cwin, + len = ((int32_t)min(cwin, tp->snd_recover - p->rxmit)); } else - len = ((long)ulmin(cwin, p->end - p->rxmit)); - off = p->rxmit - tp->snd_una; + len = ((int32_t)min(cwin, p->end - p->rxmit)); if (len > 0) { + off = p->rxmit - tp->snd_una; /* update off only if we really transmit SACK data */ sack_rxmit = 1; sendalot = 1; tcpstat.tcps_sack_rexmits++; tcpstat.tcps_sack_rexmit_bytes += min(len, tp->t_maxseg); } + else + len = 0; } after_sack_rexmit: /* @@ -507,17 +527,17 @@ after_sack_rexmit: */ if (sack_rxmit == 0) { if (sack_bytes_rxmt == 0) - len = ((long)ulmin(so->so_snd.sb_cc, sendwin) - off); + len = min(so->so_snd.sb_cc, sendwin) - off; else { - long cwin; + int32_t cwin; /* * We are inside of a SACK recovery episode and are * sending new data, having retransmitted all the * data possible in the scoreboard. */ - len = ((long)ulmin(so->so_snd.sb_cc, tp->snd_wnd) - - off); + len = min(so->so_snd.sb_cc, tp->snd_wnd) + - off; /* * Don't remove this (len > 0) check ! * We explicitly check for len > 0 here (although it @@ -532,8 +552,10 @@ after_sack_rexmit: sack_bytes_rxmt; if (cwin < 0) cwin = 0; - len = lmin(len, cwin); + len = imin(len, cwin); } + else + len = 0; } } @@ -556,7 +578,7 @@ after_sack_rexmit: error = tcp_ip_output(so, tp, packetlist, packchain_listadd, tp_inp_options, - (so_options & SO_DONTROUTE)); + (so_options & SO_DONTROUTE), (sack_rxmit | (sack_bytes_rxmt != 0))); tp->t_flags &= ~TF_SENDINPROG; } @@ -604,13 +626,53 @@ after_sack_rexmit: } /* - * len will be >= 0 after this point. Truncate to the maximum - * segment length and ensure that FIN is removed if the length - * no longer contains the last data byte. + * Truncate to the maximum segment length or enable TCP Segmentation + * Offloading (if supported by hardware) and ensure that FIN is removed + * if the length no longer contains the last data byte. + * + * TSO may only be used if we are in a pure bulk sending state. The + * presence of TCP-MD5, SACK retransmits, SACK advertizements, ipfw rules + * and IP options prevent using TSO. With TSO the TCP header is the same + * (except for the sequence number) for all generated packets. This + * makes it impossible to transmit any options which vary per generated + * segment or packet. + * + * The length of TSO bursts is limited to TCP_MAXWIN. That limit and + * removal of FIN (if not already catched here) are handled later after + * the exact length of the TCP options are known. */ +#if IPSEC + /* + * Pre-calculate here as we save another lookup into the darknesses + * of IPsec that way and can actually decide if TSO is ok. + */ + if (ipsec_bypass == 0) + ipsec_optlen = ipsec_hdrsiz_tcp(tp); +#endif + if (len > tp->t_maxseg) { - len = tp->t_maxseg; - sendalot = 1; + if ((tp->t_flags & TF_TSO) && tcp_do_tso && +#if RANDOM_IP_ID + ip_use_randomid && +#endif /* RANDOM_IP_ID */ + kipf_count == 0 && dlil_filter_count == 0 && + tp->rcv_numsacks == 0 && sack_rxmit == 0 && sack_bytes_rxmt == 0 && + tp->t_inpcb->inp_options == NULL && + tp->t_inpcb->in6p_options == NULL +#if IPSEC + && ipsec_optlen == 0 +#endif +#if IPFIREWALL + && (fw_enable == 0 || fw_bypass) +#endif + ) { + tso = 1; + sendalot = 0; + } else { + len = tp->t_maxseg; + sendalot = 1; + tso = 0; + } } if (sack_rxmit) { if (SEQ_LT(p->rxmit + len, tp->snd_una + so->so_snd.sb_cc)) @@ -626,7 +688,7 @@ after_sack_rexmit: * Sender silly window avoidance. We transmit under the following * conditions when len is non-zero: * - * - We have a full segment + * - We have a full segment (or more with TSO) * - 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) @@ -635,7 +697,7 @@ after_sack_rexmit: * - we need to retransmit */ if (len) { - if (len == tp->t_maxseg) { + if (len >= tp->t_maxseg) { tp->t_flags |= TF_MAXSEGSNT; goto send; } @@ -676,10 +738,10 @@ after_sack_rexmit: * taking into account that we are limited by * TCP_MAXWIN << tp->rcv_scale. */ - long adv = lmin(recwin, (long)TCP_MAXWIN << tp->rcv_scale) - + int32_t adv = imin(recwin, (int)TCP_MAXWIN << tp->rcv_scale) - (tp->rcv_adv - tp->rcv_nxt); - if (adv >= (long) (2 * tp->t_maxseg)) { + if (adv >= (int32_t) (2 * tp->t_maxseg)) { /* * Update only if the resulting scaled value of the window changed, or @@ -690,7 +752,7 @@ after_sack_rexmit: if ((tp->last_ack_sent != tp->rcv_nxt) || (((recwin + adv) >> tp->rcv_scale) > recwin)) goto send; } - if (2 * adv >= (long) so->so_rcv.sb_hiwat) + if (2 * adv >= (int32_t) so->so_rcv.sb_hiwat) goto send; } @@ -763,7 +825,7 @@ just_return: tp->t_flags |= TF_SENDINPROG; error = tcp_ip_output(so, tp, packetlist, packchain_listadd, - tp_inp_options, (so_options & SO_DONTROUTE)); + tp_inp_options, (so_options & SO_DONTROUTE), (sack_rxmit | (sack_bytes_rxmt != 0))); tp->t_flags &= ~TF_SENDINPROG; } @@ -1015,8 +1077,7 @@ send: ipoptlen = 0; } #if IPSEC - if (ipsec_bypass == 0) - ipoptlen += ipsec_hdrsiz_tcp(tp); + ipoptlen += ipsec_optlen; #endif /* @@ -1024,14 +1085,34 @@ send: * bump the packet length beyond the t_maxopd length. * Clear the FIN bit because we cut off the tail of * the segment. + * + * When doing TSO limit a burst to TCP_MAXWIN minus the + * IP, TCP and Options length to keep ip->ip_len from + * overflowing. Prevent the last segment from being + * fractional thus making them all equal sized and set + * the flag to continue sending. TSO is disabled when + * IP options or IPSEC are present. */ if (len + optlen + ipoptlen > tp->t_maxopd) { /* * If there is still more to send, don't close the connection. */ flags &= ~TH_FIN; - len = tp->t_maxopd - optlen - ipoptlen; - sendalot = 1; + if (tso) { + int32_t tso_maxlen; + + tso_maxlen = tp->tso_max_segment_size ? tp->tso_max_segment_size : TCP_MAXWIN; + + if (len > tso_maxlen - hdrlen - optlen) { + len = tso_maxlen - hdrlen - optlen; + len = len - (len % (tp->t_maxopd - optlen)); + sendalot = 1; + } else if (tp->t_flags & TF_NEEDFIN) + sendalot = 1; + } else { + len = tp->t_maxopd - optlen - ipoptlen; + sendalot = 1; + } } /*#ifdef DIAGNOSTIC*/ @@ -1052,7 +1133,7 @@ send: if (len) { if (tp->t_force && len == 1) tcpstat.tcps_sndprobe++; - else if (SEQ_LT(tp->snd_nxt, tp->snd_max)) { + else if (SEQ_LT(tp->snd_nxt, tp->snd_max) || sack_rxmit) { tcpstat.tcps_sndrexmitpack++; tcpstat.tcps_sndrexmitbyte += len; } else { @@ -1112,7 +1193,7 @@ send: m->m_len = hdrlen; } /* makes sure we still have data left to be sent at this point */ - if (so->so_snd.sb_mb == NULL || off == -1) { + if (so->so_snd.sb_mb == NULL || off < 0) { if (m != NULL) m_freem(m); error = 0; /* should we return an error? */ goto out; @@ -1139,7 +1220,7 @@ send: * m_copym_with_hdrs to avoid rescanning from the beginning of the socket buffer mbuf list. * setting the mbuf pointer to NULL is sufficient to disable the hint mechanism. */ - if (m_head != so->so_snd.sb_mb || last_off != off) + if (m_head != so->so_snd.sb_mb || sack_rxmit || last_off != off) m_last = NULL; last_off = off + len; m_head = so->so_snd.sb_mb; @@ -1154,7 +1235,7 @@ send: * m_copym_with_hdrs will always return the last mbuf pointer and the offset into it that * it acted on to fullfill the current request, whether a valid 'hint' was passed in or not */ - if ((m = m_copym_with_hdrs(so->so_snd.sb_mb, off, (int) len, M_DONTWAIT, &m_last, &m_off)) == NULL) { + if ((m = m_copym_with_hdrs(so->so_snd.sb_mb, off, len, M_DONTWAIT, &m_last, &m_off)) == NULL) { error = ENOBUFS; goto out; } @@ -1261,18 +1342,18 @@ send: * Calculate receive window. Don't shrink window, * but avoid silly window syndrome. */ - if (recwin < (long)(so->so_rcv.sb_hiwat / 4) && recwin < (long)tp->t_maxseg) + if (recwin < (int32_t)(so->so_rcv.sb_hiwat / 4) && recwin < (int)tp->t_maxseg) recwin = 0; - if (recwin < (long)(tp->rcv_adv - tp->rcv_nxt)) - recwin = (long)(tp->rcv_adv - tp->rcv_nxt); + if (recwin < (int32_t)(tp->rcv_adv - tp->rcv_nxt)) + recwin = (int32_t)(tp->rcv_adv - tp->rcv_nxt); if (tp->t_flags & TF_SLOWLINK && slowlink_wsize > 0) { - if (recwin > (long)slowlink_wsize) + if (recwin > (int32_t)slowlink_wsize) recwin = slowlink_wsize; - th->th_win = htons((u_short) (recwin>>tp->rcv_scale)); + th->th_win = htons((u_short) (recwin>>tp->rcv_scale)); } else { - if (recwin > (long)(TCP_MAXWIN << tp->rcv_scale)) - recwin = (long)(TCP_MAXWIN << tp->rcv_scale); + if (recwin > (int32_t)(TCP_MAXWIN << tp->rcv_scale)) + recwin = (int32_t)(TCP_MAXWIN << tp->rcv_scale); th->th_win = htons((u_short) (recwin>>tp->rcv_scale)); } @@ -1323,6 +1404,24 @@ send: htons((u_short)(optlen + len))); } + /* + * Enable TSO and specify the size of the segments. + * The TCP pseudo header checksum is always provided. + * XXX: Fixme: This is currently not the case for IPv6. + */ + if (tso) { +#if INET6 + if (isipv6) + m->m_pkthdr.csum_flags = CSUM_TSO_IPV6; + else +#endif /* INET6 */ + m->m_pkthdr.csum_flags = CSUM_TSO_IPV4; + + m->m_pkthdr.tso_segsz = tp->t_maxopd - optlen; + } + else + m->m_pkthdr.tso_segsz = 0; + /* * In transmit state, time the transmission and arrange for * the retransmit. In persist state, just set snd_max. @@ -1519,7 +1618,7 @@ timer: error = tcp_ip_output(so, tp, packetlist, packchain_listadd, tp_inp_options, - (so_options & SO_DONTROUTE)); + (so_options & SO_DONTROUTE), (sack_rxmit | (sack_bytes_rxmt != 0))); tp->t_flags &= ~TF_SENDINPROG; if (error) { @@ -1581,10 +1680,13 @@ out: TCP_PKTLIST_CLEAR(tp); if (error == ENOBUFS) { - if (!tp->t_timer[TCPT_REXMT] && - !tp->t_timer[TCPT_PERSIST]) - tp->t_timer[TCPT_REXMT] = tp->t_rxtcur; - tcp_quench(tp->t_inpcb, 0); + if (!tp->t_timer[TCPT_REXMT] && + !tp->t_timer[TCPT_PERSIST]) + tp->t_timer[TCPT_REXMT] = tp->t_rxtcur; + + tp->snd_cwnd = tp->t_maxseg; + tp->t_bytes_acked = 0; + KERNEL_DEBUG(DBG_FNC_TCP_OUTPUT | DBG_FUNC_END, 0,0,0,0,0); return (0); } @@ -1594,7 +1696,16 @@ out: * for us. tcp_mtudisc() will, as its last action, * initiate retransmission, so it is important to * not do so here. + * + * If TSO was active we either got an interface + * without TSO capabilits or TSO was turned off. + * Disable it for this connection as too and + * immediatly retry with MSS sized segments generated + * by this function. */ + if (tso) + tp->t_flags &= ~TF_TSO; + tcp_mtudisc(tp->t_inpcb, 0); KERNEL_DEBUG(DBG_FNC_TCP_OUTPUT | DBG_FUNC_END, 0,0,0,0,0); return 0; @@ -1617,7 +1728,7 @@ out: * then remember the size of the advertised window. * Any pending ACK has now been sent. */ - if (recwin > 0 && SEQ_GT(tp->rcv_nxt+recwin, tp->rcv_adv)) + if (recwin > 0 && SEQ_GT(tp->rcv_nxt + recwin, tp->rcv_adv)) tp->rcv_adv = tp->rcv_nxt + recwin; tp->last_ack_sent = tp->rcv_nxt; tp->t_flags &= ~(TF_ACKNOW|TF_DELACK); @@ -1630,29 +1741,40 @@ out: static int tcp_ip_output(struct socket *so, struct tcpcb *tp, struct mbuf *pkt, - int cnt, struct mbuf *opt, int flags) + int cnt, struct mbuf *opt, int flags, int sack_in_progress) { int error = 0; boolean_t chain; boolean_t unlocked = FALSE; + struct inpcb *inp = tp->t_inpcb; + struct ip_out_args ipoa; + struct route ro; + + /* If socket was bound to an ifindex, tell ip_output about it */ + ipoa.ipoa_ifscope = (inp->inp_flags & INP_BOUND_IF) ? + inp->inp_boundif : IFSCOPE_NONE; + flags |= IP_OUTARGS; + + /* Copy the cached route and take an extra reference */ + inp_route_copyout(inp, &ro); - /* Make sure ACK/DELACK conditions are cleared before + /* + * Make sure ACK/DELACK conditions are cleared before * we unlock the socket. */ - tp->t_flags &= ~(TF_ACKNOW | TF_DELACK); + /* - * If allowed, unlock TCP socket while in IP + * If allowed, unlock TCP socket while in IP * but only if the connection is established and * if we're not sending from an upcall. - */ - + */ if (tcp_output_unlocked && ((so->so_flags & SOF_UPCALLINUSE) == 0) && - (tp->t_state == TCPS_ESTABLISHED)) { - unlocked = TRUE; - socket_unlock(so, 0); + (tp->t_state == TCPS_ESTABLISHED) && (sack_in_progress == 0)) { + unlocked = TRUE; + socket_unlock(so, 0); } - + /* * Don't send down a chain of packets when: * - TCP chaining is disabled @@ -1688,13 +1810,7 @@ tcp_ip_output(struct socket *so, struct tcpcb *tp, struct mbuf *pkt, */ cnt = 0; } -#if CONFIG_FORCE_OUT_IFP - error = ip_output_list(pkt, cnt, opt, &tp->t_inpcb->inp_route, - flags, 0, tp->t_inpcb->pdp_ifp); -#else - error = ip_output_list(pkt, cnt, opt, &tp->t_inpcb->inp_route, - flags, 0, NULL); -#endif + error = ip_output_list(pkt, cnt, opt, &ro, flags, 0, &ipoa); if (chain || error) { /* * If we sent down a chain then we are done since @@ -1711,6 +1827,9 @@ tcp_ip_output(struct socket *so, struct tcpcb *tp, struct mbuf *pkt, if (unlocked) socket_lock(so, 0); + /* Synchronize cached PCB route */ + inp_route_copyin(inp, &ro); + return (error); }