/* * Copyright (c) 2000-2022 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* * 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. 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. * * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95 */ /* * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce * support for mandatory and extensible security protections. This notice * is included in support of clause 2.2 (b) of the Apple Public License, * Version 2.0. */ #include "tcp_includes.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define tcp_minmssoverload fring #define _IP_VHL #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if TCPDEBUG #include #endif #include #include #if IPSEC #include #include #endif /* IPSEC */ #if NECP #include #endif /* NECP */ #undef tcp_minmssoverload #include #include #include #include #include #include #include #define DBG_FNC_TCP_CLOSE NETDBG_CODE(DBG_NETTCP, ((5 << 8) | 2)) static tcp_cc tcp_ccgen; extern struct tcptimerlist tcp_timer_list; extern struct tcptailq tcp_tw_tailq; extern int tcp_awdl_rtobase; SYSCTL_SKMEM_TCP_INT(TCPCTL_MSSDFLT, mssdflt, CTLFLAG_RW | CTLFLAG_LOCKED, int, tcp_mssdflt, TCP_MSS, "Default TCP Maximum Segment Size"); SYSCTL_SKMEM_TCP_INT(TCPCTL_V6MSSDFLT, v6mssdflt, CTLFLAG_RW | CTLFLAG_LOCKED, int, tcp_v6mssdflt, TCP6_MSS, "Default TCP Maximum Segment Size for IPv6"); int tcp_sysctl_fastopenkey(struct sysctl_oid *, void *, int, struct sysctl_req *); SYSCTL_PROC(_net_inet_tcp, OID_AUTO, fastopen_key, CTLTYPE_STRING | CTLFLAG_WR, 0, 0, tcp_sysctl_fastopenkey, "S", "TCP Fastopen key"); /* Current count of half-open TFO connections */ int tcp_tfo_halfcnt = 0; /* Maximum of half-open TFO connection backlog */ SYSCTL_SKMEM_TCP_INT(OID_AUTO, fastopen_backlog, CTLFLAG_RW | CTLFLAG_LOCKED, int, tcp_tfo_backlog, 10, "Backlog queue for half-open TFO connections"); SYSCTL_SKMEM_TCP_INT(OID_AUTO, fastopen, CTLFLAG_RW | CTLFLAG_LOCKED, int, tcp_fastopen, TCP_FASTOPEN_CLIENT | TCP_FASTOPEN_SERVER, "Enable TCP Fastopen (RFC 7413)"); SYSCTL_SKMEM_TCP_INT(OID_AUTO, now_init, CTLFLAG_RD | CTLFLAG_LOCKED, uint32_t, tcp_now_init, 0, "Initial tcp now value"); SYSCTL_SKMEM_TCP_INT(OID_AUTO, microuptime_init, CTLFLAG_RD | CTLFLAG_LOCKED, uint32_t, tcp_microuptime_init, 0, "Initial tcp uptime value in micro seconds"); /* * 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. */ SYSCTL_SKMEM_TCP_INT(OID_AUTO, minmss, CTLFLAG_RW | CTLFLAG_LOCKED, int, tcp_minmss, TCP_MINMSS, "Minmum TCP Maximum Segment Size"); SYSCTL_INT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_RD | CTLFLAG_LOCKED, &tcbinfo.ipi_count, 0, "Number of active PCBs"); SYSCTL_INT(_net_inet_tcp, OID_AUTO, tw_pcbcount, CTLFLAG_RD | CTLFLAG_LOCKED, &tcbinfo.ipi_twcount, 0, "Number of pcbs in time-wait state"); SYSCTL_SKMEM_TCP_INT(OID_AUTO, icmp_may_rst, CTLFLAG_RW | CTLFLAG_LOCKED, static int, icmp_may_rst, 1, "Certain ICMP unreachable messages may abort connections in SYN_SENT"); static int tcp_strict_rfc1948 = 0; static int tcp_isn_reseed_interval = 0; int tcp_do_timestamps = 1; #if (DEVELOPMENT || DEBUG) SYSCTL_INT(_net_inet_tcp, OID_AUTO, strict_rfc1948, CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_strict_rfc1948, 0, "Determines if RFC1948 is followed exactly"); SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_isn_reseed_interval, 0, "Seconds between reseeding of ISN secret"); SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_timestamps, CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_do_timestamps, 0, "enable TCP timestamps"); #endif /* (DEVELOPMENT || DEBUG) */ SYSCTL_SKMEM_TCP_INT(OID_AUTO, rtt_min, CTLFLAG_RW | CTLFLAG_LOCKED, int, tcp_TCPTV_MIN, 100, "min rtt value allowed"); SYSCTL_SKMEM_TCP_INT(OID_AUTO, rexmt_slop, CTLFLAG_RW, int, tcp_rexmt_slop, TCPTV_REXMTSLOP, "Slop added to retransmit timeout"); SYSCTL_SKMEM_TCP_INT(OID_AUTO, randomize_ports, CTLFLAG_RW | CTLFLAG_LOCKED, __private_extern__ int, tcp_use_randomport, 0, "Randomize TCP port numbers"); SYSCTL_SKMEM_TCP_INT(OID_AUTO, win_scale_factor, CTLFLAG_RW | CTLFLAG_LOCKED, __private_extern__ int, tcp_win_scale, 3, "Window scaling factor"); #if (DEVELOPMENT || DEBUG) SYSCTL_SKMEM_TCP_INT(OID_AUTO, init_rtt_from_cache, CTLFLAG_RW | CTLFLAG_LOCKED, static int, tcp_init_rtt_from_cache, 1, "Initalize RTT from route cache"); #else SYSCTL_SKMEM_TCP_INT(OID_AUTO, init_rtt_from_cache, CTLFLAG_RD | CTLFLAG_LOCKED, static int, tcp_init_rtt_from_cache, 1, "Initalize RTT from route cache"); #endif /* (DEVELOPMENT || DEBUG) */ static int tso_debug = 0; SYSCTL_INT(_net_inet_tcp, OID_AUTO, tso_debug, CTLFLAG_RW | CTLFLAG_LOCKED, &tso_debug, 0, "TSO verbosity"); static int tcp_rxt_seg_max = 1024; SYSCTL_INT(_net_inet_tcp, OID_AUTO, rxt_seg_max, CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_rxt_seg_max, 0, ""); static unsigned long tcp_rxt_seg_drop = 0; SYSCTL_ULONG(_net_inet_tcp, OID_AUTO, rxt_seg_drop, CTLFLAG_RD | CTLFLAG_LOCKED, &tcp_rxt_seg_drop, ""); static void tcp_notify(struct inpcb *, int); static KALLOC_TYPE_DEFINE(tcp_bwmeas_zone, struct bwmeas, NET_KT_DEFAULT); KALLOC_TYPE_DEFINE(tcp_reass_zone, struct tseg_qent, NET_KT_DEFAULT); KALLOC_TYPE_DEFINE(tcp_rxt_seg_zone, struct tcp_rxt_seg, NET_KT_DEFAULT); extern int slowlink_wsize; /* window correction for slow links */ extern int path_mtu_discovery; uint32_t tcp_now_remainder_us = 0; /* remaining micro seconds for tcp_now */ static void tcp_sbrcv_grow_rwin(struct tcpcb *tp, struct sockbuf *sb); #define TCP_BWMEAS_BURST_MINSIZE 6 #define TCP_BWMEAS_BURST_MAXSIZE 25 /* * 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 CONFIG_TCBHASHSIZE #endif __private_extern__ int tcp_tcbhashsize = TCBHASHSIZE; SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RD | CTLFLAG_LOCKED, &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable"); /* * This is the actual shape of what we allocate using the zone * allocator. Doing it this way allows us to protect both structures * using the same generation count, and also eliminates the overhead * of allocating tcpcbs separately. By hiding the structure here, * we avoid changing most of the rest of the code (although it needs * to be changed, eventually, for greater efficiency). */ #define ALIGNMENT 32 struct inp_tp { struct inpcb inp; struct tcpcb tcb __attribute__((aligned(ALIGNMENT))); }; #undef ALIGNMENT static KALLOC_TYPE_DEFINE(tcpcbzone, struct inp_tp, NET_KT_DEFAULT); int get_inpcb_str_size(void); int get_tcp_str_size(void); os_log_t tcp_mpkl_log_object = NULL; static void tcpcb_to_otcpcb(struct tcpcb *, struct otcpcb *); int tcp_notsent_lowat_check(struct socket *so); static void tcp_flow_lim_stats(struct ifnet_stats_per_flow *ifs, struct if_lim_perf_stat *stat); static void tcp_flow_ecn_perf_stats(struct ifnet_stats_per_flow *ifs, struct if_tcp_ecn_perf_stat *stat); static aes_encrypt_ctx tfo_ctx; /* Crypto-context for TFO */ void tcp_tfo_gen_cookie(struct inpcb *inp, u_char *out, size_t blk_size) { u_char in[CCAES_BLOCK_SIZE]; int isipv6 = inp->inp_vflag & INP_IPV6; VERIFY(blk_size == CCAES_BLOCK_SIZE); bzero(&in[0], CCAES_BLOCK_SIZE); bzero(&out[0], CCAES_BLOCK_SIZE); if (isipv6) { memcpy(in, &inp->in6p_faddr, sizeof(struct in6_addr)); } else { memcpy(in, &inp->inp_faddr, sizeof(struct in_addr)); } aes_encrypt_cbc(in, NULL, 1, out, &tfo_ctx); } __private_extern__ int tcp_sysctl_fastopenkey(__unused struct sysctl_oid *oidp, __unused void *arg1, __unused int arg2, struct sysctl_req *req) { int error = 0; /* * TFO-key is expressed as a string in hex format * +1 to account for the \0 char * +1 because sysctl_io_string() expects a string length but the sysctl command * now includes the terminating \0 in newlen -- see rdar://77205344 */ char keystring[TCP_FASTOPEN_KEYLEN * 2 + 2]; u_int32_t key[TCP_FASTOPEN_KEYLEN / sizeof(u_int32_t)]; int i; /* * sysctl_io_string copies keystring into the oldptr of the sysctl_req. * Make sure everything is zero, to avoid putting garbage in there or * leaking the stack. */ bzero(keystring, sizeof(keystring)); error = sysctl_io_string(req, keystring, sizeof(keystring), 0, NULL); if (error) { os_log(OS_LOG_DEFAULT, "%s: sysctl_io_string() error %d, req->newlen %lu, sizeof(keystring) %lu", __func__, error, req->newlen, sizeof(keystring)); goto exit; } if (req->newptr == USER_ADDR_NULL) { goto exit; } if (strlen(keystring) != TCP_FASTOPEN_KEYLEN * 2) { os_log(OS_LOG_DEFAULT, "%s: strlen(keystring) %lu != TCP_FASTOPEN_KEYLEN * 2 %u, newlen %lu", __func__, strlen(keystring), TCP_FASTOPEN_KEYLEN * 2, req->newlen); error = EINVAL; goto exit; } for (i = 0; i < (TCP_FASTOPEN_KEYLEN / sizeof(u_int32_t)); i++) { /* * We jump over the keystring in 8-character (4 byte in hex) * steps */ if (sscanf(&keystring[i * 8], "%8x", &key[i]) != 1) { error = EINVAL; os_log(OS_LOG_DEFAULT, "%s: sscanf() != 1, error EINVAL", __func__); goto exit; } } aes_encrypt_key128((u_char *)key, &tfo_ctx); exit: return error; } int get_inpcb_str_size(void) { return sizeof(struct inpcb); } int get_tcp_str_size(void) { return sizeof(struct tcpcb); } static int scale_to_powerof2(int size); /* * This helper routine returns one of the following scaled value of size: * 1. Rounded down power of two value of size if the size value passed as * argument is not a power of two and the rounded up value overflows. * OR * 2. Rounded up power of two value of size if the size value passed as * argument is not a power of two and the rounded up value does not overflow * OR * 3. Same value as argument size if it is already a power of two. */ static int scale_to_powerof2(int size) { /* Handle special case of size = 0 */ int ret = size ? size : 1; if (!powerof2(ret)) { while (!powerof2(size)) { /* * Clear out least significant * set bit till size is left with * its highest set bit at which point * it is rounded down power of two. */ size = size & (size - 1); } /* Check for overflow when rounding up */ if (0 == (size << 1)) { ret = size; } else { ret = size << 1; } } return ret; } /* * Round the floating point to the next integer * Eg. 1.3 will round up to 2. */ uint32_t tcp_ceil(double a) { double res = (uint32_t) a; return (uint32_t)(res + (res < a)); } uint32_t tcp_round_to(uint32_t val, uint32_t round) { /* * Round up or down based on the middle. Meaning, if we round upon a * multiple of 10, 16 will round to 20 and 14 will round to 10. */ return ((val + (round / 2)) / round) * round; } /* * Round up to the next multiple of base. * Eg. for a base of 64, 65 will become 128, * 2896 will become 2944. */ uint32_t tcp_round_up(uint32_t val, uint32_t base) { if (base == 1 || val % base == 0) { return val; } return ((val + base) / base) * base; } static void tcp_tfo_init(void) { u_char key[TCP_FASTOPEN_KEYLEN]; read_frandom(key, sizeof(key)); aes_encrypt_key128(key, &tfo_ctx); } /* * Tcp initialization */ void tcp_init(struct protosw *pp, struct domain *dp) { #pragma unused(dp) static int tcp_initialized = 0; struct inpcbinfo *pcbinfo; VERIFY((pp->pr_flags & (PR_INITIALIZED | PR_ATTACHED)) == PR_ATTACHED); if (tcp_initialized) { return; } tcp_initialized = 1; #if DEBUG || DEVELOPMENT (void) PE_parse_boot_argn("tcp_rxt_seg_max", &tcp_rxt_seg_max, sizeof(tcp_rxt_seg_max)); #endif /* DEBUG || DEVELOPMENT */ tcp_ccgen = 1; tcp_keepinit = TCPTV_KEEP_INIT; tcp_keepidle = TCPTV_KEEP_IDLE; tcp_keepintvl = TCPTV_KEEPINTVL; tcp_keepcnt = TCPTV_KEEPCNT; tcp_maxpersistidle = TCPTV_KEEP_IDLE; tcp_msl = TCPTV_MSL; microuptime(&tcp_uptime); read_frandom(&tcp_now, sizeof(tcp_now)); /* Starts tcp internal clock at a random value */ tcp_now = tcp_now & 0x3fffffff; /* expose initial uptime/now via systcl for utcp to keep time sync */ tcp_now_init = tcp_now; tcp_microuptime_init = (uint32_t)(tcp_uptime.tv_usec + (tcp_uptime.tv_sec * USEC_PER_SEC)); SYSCTL_SKMEM_UPDATE_FIELD(tcp.microuptime_init, tcp_microuptime_init); SYSCTL_SKMEM_UPDATE_FIELD(tcp.now_init, tcp_now_init); tcp_tfo_init(); LIST_INIT(&tcb); tcbinfo.ipi_listhead = &tcb; pcbinfo = &tcbinfo; /* * allocate group, lock attributes and lock for tcp pcb mutexes */ pcbinfo->ipi_lock_grp = lck_grp_alloc_init("tcppcb", LCK_GRP_ATTR_NULL); lck_attr_setdefault(&pcbinfo->ipi_lock_attr); lck_rw_init(&pcbinfo->ipi_lock, pcbinfo->ipi_lock_grp, &pcbinfo->ipi_lock_attr); if (tcp_tcbhashsize == 0) { /* Set to default */ tcp_tcbhashsize = 512; } if (!powerof2(tcp_tcbhashsize)) { int old_hash_size = tcp_tcbhashsize; tcp_tcbhashsize = scale_to_powerof2(tcp_tcbhashsize); /* Lower limit of 16 */ if (tcp_tcbhashsize < 16) { tcp_tcbhashsize = 16; } printf("WARNING: TCB hash size not a power of 2, " "scaled from %d to %d.\n", old_hash_size, tcp_tcbhashsize); } tcbinfo.ipi_hashbase = hashinit(tcp_tcbhashsize, M_PCB, &tcbinfo.ipi_hashmask); tcbinfo.ipi_porthashbase = hashinit(tcp_tcbhashsize, M_PCB, &tcbinfo.ipi_porthashmask); tcbinfo.ipi_zone = tcpcbzone; tcbinfo.ipi_gc = tcp_gc; tcbinfo.ipi_timer = tcp_itimer; in_pcbinfo_attach(&tcbinfo); #define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr)) if (max_protohdr < TCP_MINPROTOHDR) { max_protohdr = (int)P2ROUNDUP(TCP_MINPROTOHDR, sizeof(uint32_t)); } if (max_linkhdr + max_protohdr > MCLBYTES) { panic("tcp_init"); } #undef TCP_MINPROTOHDR /* Initialize time wait and timer lists */ TAILQ_INIT(&tcp_tw_tailq); bzero(&tcp_timer_list, sizeof(tcp_timer_list)); LIST_INIT(&tcp_timer_list.lhead); /* * allocate group and attribute for the tcp timer list */ tcp_timer_list.mtx_grp = lck_grp_alloc_init("tcptimerlist", LCK_GRP_ATTR_NULL); lck_mtx_init(&tcp_timer_list.mtx, tcp_timer_list.mtx_grp, LCK_ATTR_NULL); tcp_timer_list.call = thread_call_allocate(tcp_run_timerlist, NULL); if (tcp_timer_list.call == NULL) { panic("failed to allocate call entry 1 in tcp_init"); } /* Initialize TCP Cache */ tcp_cache_init(); tcp_mpkl_log_object = MPKL_CREATE_LOGOBJECT("com.apple.xnu.tcp"); if (tcp_mpkl_log_object == NULL) { panic("MPKL_CREATE_LOGOBJECT failed"); } if (PE_parse_boot_argn("tcp_log", &tcp_log_enable_flags, sizeof(tcp_log_enable_flags))) { os_log(OS_LOG_DEFAULT, "tcp_init: set tcp_log_enable_flags to 0x%x", tcp_log_enable_flags); } /* * If more than 4GB of actual memory is available, increase the * maximum allowed receive and send socket buffer size. */ if (mem_actual >= (1ULL << (GBSHIFT + 2))) { tcp_autorcvbuf_max = 4 * 1024 * 1024; tcp_autosndbuf_max = 4 * 1024 * 1024; SYSCTL_SKMEM_UPDATE_FIELD(tcp.autorcvbufmax, tcp_autorcvbuf_max); SYSCTL_SKMEM_UPDATE_FIELD(tcp.autosndbufmax, tcp_autosndbuf_max); } /* Initialize the TCP CCA array */ tcp_cc_init(); } /* * 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 tcp_fillheaders(struct mbuf *m, struct tcpcb *tp, void *ip_ptr, void *tcp_ptr) { struct inpcb *inp = tp->t_inpcb; struct tcphdr *tcp_hdr = (struct tcphdr *)tcp_ptr; 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); ip6->ip6_plen = htons(sizeof(struct tcphdr)); ip6->ip6_nxt = IPPROTO_TCP; ip6->ip6_hlim = 0; ip6->ip6_src = inp->in6p_laddr; ip6->ip6_dst = inp->in6p_faddr; if (m->m_flags & M_PKTHDR) { uint32_t lifscope = inp->inp_lifscope != 0 ? inp->inp_lifscope : inp->inp_fifscope; uint32_t fifscope = inp->inp_fifscope != 0 ? inp->inp_fifscope : inp->inp_lifscope; ip6_output_setsrcifscope(m, lifscope, NULL); ip6_output_setdstifscope(m, fifscope, NULL); } tcp_hdr->th_sum = in6_pseudo(&inp->in6p_laddr, &inp->in6p_faddr, htonl(sizeof(struct tcphdr) + IPPROTO_TCP)); } else { struct ip *ip = (struct ip *) ip_ptr; ip->ip_vhl = IP_VHL_BORING; ip->ip_tos = 0; ip->ip_len = 0; ip->ip_id = 0; ip->ip_off = 0; ip->ip_ttl = 0; ip->ip_sum = 0; ip->ip_p = IPPROTO_TCP; ip->ip_src = inp->inp_laddr; ip->ip_dst = inp->inp_faddr; tcp_hdr->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, htons(sizeof(struct tcphdr) + IPPROTO_TCP)); } tcp_hdr->th_sport = inp->inp_lport; tcp_hdr->th_dport = inp->inp_fport; tcp_hdr->th_seq = 0; tcp_hdr->th_ack = 0; tcp_hdr->th_x2 = 0; tcp_hdr->th_off = 5; tcp_hdr->th_flags = 0; tcp_hdr->th_win = 0; tcp_hdr->th_urp = 0; } /* * 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 * tcp_maketemplate(struct tcpcb *tp, struct mbuf **mp) { struct mbuf *m; struct tcptemp *n; *mp = m = m_get(M_DONTWAIT, MT_HEADER); if (m == NULL) { return NULL; } m->m_len = sizeof(struct tcptemp); n = mtod(m, struct tcptemp *); tcp_fillheaders(m, tp, (void *)&n->tt_ipgen, (void *)&n->tt_t); return n; } /* * Send a single message to the TCP at address specified by * the given TCP/IP header. If m == 0, then we make a copy * of the tcpiphdr at ti 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 ti, * 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 ti 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, uint8_t flags, struct tcp_respond_args *tra) { uint16_t tlen; int win = 0; struct route *ro = 0; struct route sro; struct ip *ip; struct tcphdr *nth; struct route_in6 *ro6 = 0; struct route_in6 sro6; struct ip6_hdr *ip6; int isipv6; struct ifnet *outif; int sotc = SO_TC_UNSPEC; bool check_qos_marking_again = FALSE; uint32_t sifscope = IFSCOPE_NONE, fifscope = IFSCOPE_NONE; isipv6 = IP_VHL_V(((struct ip *)ipgen)->ip_vhl) == 6; ip6 = ipgen; ip = ipgen; if (tp) { check_qos_marking_again = tp->t_inpcb->inp_socket->so_flags1 & SOF1_QOSMARKING_POLICY_OVERRIDE ? FALSE : TRUE; sifscope = tp->t_inpcb->inp_lifscope; fifscope = tp->t_inpcb->inp_fifscope; if (!(flags & TH_RST)) { win = tcp_sbspace(tp); if (win > (int32_t)TCP_MAXWIN << tp->rcv_scale) { win = (int32_t)TCP_MAXWIN << tp->rcv_scale; } } if (isipv6) { ro6 = &tp->t_inpcb->in6p_route; } else { ro = &tp->t_inpcb->inp_route; } } else { if (isipv6) { ro6 = &sro6; bzero(ro6, sizeof(*ro6)); } else { ro = &sro; bzero(ro, sizeof(*ro)); } } if (m == 0) { m = m_gethdr(M_DONTWAIT, MT_HEADER); /* MAC-OK */ if (m == NULL) { return; } tlen = 0; m->m_data += max_linkhdr; if (isipv6) { VERIFY((MHLEN - max_linkhdr) >= (sizeof(*ip6) + sizeof(*nth))); bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(struct ip6_hdr)); ip6 = mtod(m, struct ip6_hdr *); nth = (struct tcphdr *)(void *)(ip6 + 1); } else { VERIFY((MHLEN - max_linkhdr) >= (sizeof(*ip) + sizeof(*nth))); bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); ip = mtod(m, struct ip *); nth = (struct tcphdr *)(void *)(ip + 1); } bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); #if MPTCP if ((tp) && (tp->t_mpflags & TMPF_RESET)) { flags = (TH_RST | TH_ACK); } else #endif flags = TH_ACK; } else { m_freem(m->m_next); m->m_next = 0; m->m_data = (uintptr_t)ipgen; /* m_len is set later */ tlen = 0; #define xchg(a, b, type) { type t; t = a; a = b; b = t; } if (isipv6) { ip6_getsrcifaddr_info(m, &sifscope, NULL); ip6_getdstifaddr_info(m, &fifscope, NULL); if (!in6_embedded_scope) { m->m_pkthdr.pkt_flags &= ~PKTF_IFAINFO; } /* Expect 32-bit aligned IP on strict-align platforms */ IP6_HDR_STRICT_ALIGNMENT_CHECK(ip6); xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); nth = (struct tcphdr *)(void *)(ip6 + 1); } else { /* Expect 32-bit aligned IP on strict-align platforms */ IP_HDR_STRICT_ALIGNMENT_CHECK(ip); xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, n_long); nth = (struct tcphdr *)(void *)(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, n_short); #undef xchg } if (isipv6) { ip6->ip6_plen = htons((u_short)(sizeof(struct tcphdr) + tlen)); tlen += sizeof(struct ip6_hdr) + sizeof(struct tcphdr); ip6_output_setsrcifscope(m, sifscope, NULL); ip6_output_setdstifscope(m, fifscope, NULL); } else { tlen += sizeof(struct tcpiphdr); ip->ip_len = tlen; ip->ip_ttl = (uint8_t)ip_defttl; } m->m_len = tlen; m->m_pkthdr.len = tlen; m->m_pkthdr.rcvif = 0; if (tra->keep_alive) { m->m_pkthdr.pkt_flags |= PKTF_KEEPALIVE; } nth->th_seq = htonl(seq); nth->th_ack = htonl(ack); nth->th_x2 = 0; nth->th_off = sizeof(struct tcphdr) >> 2; nth->th_flags = flags; if (tp) { nth->th_win = htons((u_short) (win >> tp->rcv_scale)); } else { nth->th_win = htons((u_short)win); } nth->th_urp = 0; if (isipv6) { nth->th_sum = 0; nth->th_sum = in6_pseudo(&ip6->ip6_src, &ip6->ip6_dst, htonl((tlen - sizeof(struct ip6_hdr)) + IPPROTO_TCP)); m->m_pkthdr.csum_flags = CSUM_TCPIPV6; m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); ip6->ip6_hlim = in6_selecthlim(tp ? tp->t_inpcb : NULL, ro6 && ro6->ro_rt ? ro6->ro_rt->rt_ifp : NULL); } else { 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))); m->m_pkthdr.csum_flags = CSUM_TCP; m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); } #if TCPDEBUG if (tp == NULL || (tp->t_inpcb->inp_socket->so_options & SO_DEBUG)) { tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0); } #endif #if NECP necp_mark_packet_from_socket(m, tp ? tp->t_inpcb : NULL, 0, 0, 0, 0); #endif /* NECP */ #if IPSEC if (tp != NULL && tp->t_inpcb->inp_sp != NULL && ipsec_setsocket(m, tp ? tp->t_inpcb->inp_socket : NULL) != 0) { m_freem(m); return; } #endif if (tp != NULL) { u_int32_t svc_flags = 0; if (isipv6) { svc_flags |= PKT_SCF_IPV6; } sotc = tp->t_inpcb->inp_socket->so_traffic_class; if ((flags & TH_RST) == 0) { set_packet_service_class(m, tp->t_inpcb->inp_socket, sotc, svc_flags); } else { m_set_service_class(m, MBUF_SC_BK_SYS); } /* Embed flowhash and flow control flags */ m->m_pkthdr.pkt_flowsrc = FLOWSRC_INPCB; m->m_pkthdr.pkt_flowid = tp->t_inpcb->inp_flowhash; m->m_pkthdr.pkt_flags |= (PKTF_FLOW_ID | PKTF_FLOW_LOCALSRC | PKTF_FLOW_ADV); m->m_pkthdr.pkt_proto = IPPROTO_TCP; m->m_pkthdr.tx_tcp_pid = tp->t_inpcb->inp_socket->last_pid; m->m_pkthdr.tx_tcp_e_pid = tp->t_inpcb->inp_socket->e_pid; if (flags & TH_RST) { m->m_pkthdr.comp_gencnt = tp->t_comp_gencnt; } } else { if (flags & TH_RST) { m->m_pkthdr.comp_gencnt = TCP_ACK_COMPRESSION_DUMMY; m_set_service_class(m, MBUF_SC_BK_SYS); } } if (isipv6) { struct ip6_out_args ip6oa; bzero(&ip6oa, sizeof(ip6oa)); ip6oa.ip6oa_boundif = tra->ifscope; ip6oa.ip6oa_flags = IP6OAF_SELECT_SRCIF | IP6OAF_BOUND_SRCADDR; ip6oa.ip6oa_sotc = SO_TC_UNSPEC; ip6oa.ip6oa_netsvctype = _NET_SERVICE_TYPE_UNSPEC; if (tra->ifscope != IFSCOPE_NONE) { ip6oa.ip6oa_flags |= IP6OAF_BOUND_IF; } if (tra->nocell) { ip6oa.ip6oa_flags |= IP6OAF_NO_CELLULAR; } if (tra->noexpensive) { ip6oa.ip6oa_flags |= IP6OAF_NO_EXPENSIVE; } if (tra->noconstrained) { ip6oa.ip6oa_flags |= IP6OAF_NO_CONSTRAINED; } if (tra->awdl_unrestricted) { ip6oa.ip6oa_flags |= IP6OAF_AWDL_UNRESTRICTED; } if (tra->intcoproc_allowed) { ip6oa.ip6oa_flags |= IP6OAF_INTCOPROC_ALLOWED; } if (tra->management_allowed) { ip6oa.ip6oa_flags |= IP6OAF_MANAGEMENT_ALLOWED; } ip6oa.ip6oa_sotc = sotc; if (tp != NULL) { if ((tp->t_inpcb->inp_socket->so_flags1 & SOF1_QOSMARKING_ALLOWED)) { ip6oa.ip6oa_flags |= IP6OAF_QOSMARKING_ALLOWED; } ip6oa.qos_marking_gencount = tp->t_inpcb->inp_policyresult.results.qos_marking_gencount; if (check_qos_marking_again) { ip6oa.ip6oa_flags |= IP6OAF_REDO_QOSMARKING_POLICY; } ip6oa.ip6oa_netsvctype = tp->t_inpcb->inp_socket->so_netsvctype; } (void) ip6_output(m, NULL, ro6, IPV6_OUTARGS, NULL, NULL, &ip6oa); if (check_qos_marking_again) { struct inpcb *inp = tp->t_inpcb; inp->inp_policyresult.results.qos_marking_gencount = ip6oa.qos_marking_gencount; if (ip6oa.ip6oa_flags & IP6OAF_QOSMARKING_ALLOWED) { inp->inp_socket->so_flags1 |= SOF1_QOSMARKING_ALLOWED; } else { inp->inp_socket->so_flags1 &= ~SOF1_QOSMARKING_ALLOWED; } } if (tp != NULL && ro6 != NULL && ro6->ro_rt != NULL && (outif = ro6->ro_rt->rt_ifp) != tp->t_inpcb->in6p_last_outifp) { tp->t_inpcb->in6p_last_outifp = outif; #if SKYWALK if (NETNS_TOKEN_VALID(&tp->t_inpcb->inp_netns_token)) { netns_set_ifnet(&tp->t_inpcb->inp_netns_token, tp->t_inpcb->in6p_last_outifp); } #endif /* SKYWALK */ } if (ro6 == &sro6) { ROUTE_RELEASE(ro6); } } else { struct ip_out_args ipoa; bzero(&ipoa, sizeof(ipoa)); ipoa.ipoa_boundif = tra->ifscope; ipoa.ipoa_flags = IPOAF_SELECT_SRCIF | IPOAF_BOUND_SRCADDR; ipoa.ipoa_sotc = SO_TC_UNSPEC; ipoa.ipoa_netsvctype = _NET_SERVICE_TYPE_UNSPEC; if (tra->ifscope != IFSCOPE_NONE) { ipoa.ipoa_flags |= IPOAF_BOUND_IF; } if (tra->nocell) { ipoa.ipoa_flags |= IPOAF_NO_CELLULAR; } if (tra->noexpensive) { ipoa.ipoa_flags |= IPOAF_NO_EXPENSIVE; } if (tra->noconstrained) { ipoa.ipoa_flags |= IPOAF_NO_CONSTRAINED; } if (tra->awdl_unrestricted) { ipoa.ipoa_flags |= IPOAF_AWDL_UNRESTRICTED; } if (tra->management_allowed) { ipoa.ipoa_flags |= IPOAF_MANAGEMENT_ALLOWED; } ipoa.ipoa_sotc = sotc; if (tp != NULL) { if ((tp->t_inpcb->inp_socket->so_flags1 & SOF1_QOSMARKING_ALLOWED)) { ipoa.ipoa_flags |= IPOAF_QOSMARKING_ALLOWED; } if (!(tp->t_inpcb->inp_socket->so_flags1 & SOF1_QOSMARKING_POLICY_OVERRIDE)) { ipoa.ipoa_flags |= IPOAF_REDO_QOSMARKING_POLICY; } ipoa.qos_marking_gencount = tp->t_inpcb->inp_policyresult.results.qos_marking_gencount; ipoa.ipoa_netsvctype = tp->t_inpcb->inp_socket->so_netsvctype; } if (ro != &sro) { /* Copy the cached route and take an extra reference */ inp_route_copyout(tp->t_inpcb, &sro); } /* * For consistency, pass a local route copy. */ (void) ip_output(m, NULL, &sro, IP_OUTARGS, NULL, &ipoa); if (check_qos_marking_again) { struct inpcb *inp = tp->t_inpcb; inp->inp_policyresult.results.qos_marking_gencount = ipoa.qos_marking_gencount; if (ipoa.ipoa_flags & IPOAF_QOSMARKING_ALLOWED) { inp->inp_socket->so_flags1 |= SOF1_QOSMARKING_ALLOWED; } else { inp->inp_socket->so_flags1 &= ~SOF1_QOSMARKING_ALLOWED; } } if (tp != NULL && sro.ro_rt != NULL && (outif = sro.ro_rt->rt_ifp) != tp->t_inpcb->inp_last_outifp) { tp->t_inpcb->inp_last_outifp = outif; #if SKYWALK if (NETNS_TOKEN_VALID(&tp->t_inpcb->inp_netns_token)) { netns_set_ifnet(&tp->t_inpcb->inp_netns_token, outif); } #endif /* SKYWALK */ } if (ro != &sro) { /* Synchronize cached PCB route */ inp_route_copyin(tp->t_inpcb, &sro); } else { ROUTE_RELEASE(&sro); } } } /* * 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 in tcp_init(). */ struct tcpcb * tcp_newtcpcb(struct inpcb *inp) { struct inp_tp *it; struct tcpcb *tp; struct socket *so = inp->inp_socket; int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; uint32_t random_32; calculate_tcp_clock(); if ((so->so_flags1 & SOF1_CACHED_IN_SOCK_LAYER) == 0) { it = (struct inp_tp *)(void *)inp; tp = &it->tcb; } else { tp = (struct tcpcb *)(void *)inp->inp_saved_ppcb; } bzero((char *) tp, sizeof(struct tcpcb)); LIST_INIT(&tp->t_segq); tp->t_maxseg = tp->t_maxopd = isipv6 ? tcp_v6mssdflt : tcp_mssdflt; tp->t_flags = TF_REQ_SCALE | (tcp_do_timestamps ? TF_REQ_TSTMP : 0); tp->t_flagsext |= TF_SACK_ENABLE; TAILQ_INIT(&tp->snd_holes); SLIST_INIT(&tp->t_rxt_segments); SLIST_INIT(&tp->t_notify_ack); tp->t_inpcb = inp; /* * 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 = ((TCPTV_RTOBASE - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; tp->t_rttmin = tcp_TCPTV_MIN; tp->t_rxtcur = TCPTV_RTOBASE; if (tcp_use_newreno) { /* use newreno by default */ tp->tcp_cc_index = TCP_CC_ALGO_NEWRENO_INDEX; #if (DEVELOPMENT || DEBUG) } else if (tcp_use_ledbat) { /* use ledbat for testing */ tp->tcp_cc_index = TCP_CC_ALGO_BACKGROUND_INDEX; #endif } else { tp->tcp_cc_index = TCP_CC_ALGO_CUBIC_INDEX; } tcp_cc_allocate_state(tp); if (CC_ALGO(tp)->init != NULL) { CC_ALGO(tp)->init(tp); } /* Initialize rledbat if we are using recv_bg */ if (tcp_rledbat == 1 && TCP_RECV_BG(inp->inp_socket) && tcp_cc_rledbat.init != NULL) { tcp_cc_rledbat.init(tp); } tp->snd_cwnd = tcp_initial_cwnd(tp); tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; tp->snd_ssthresh_prev = TCP_MAXWIN << TCP_MAX_WINSHIFT; tp->t_rcvtime = tcp_now; tp->tentry.timer_start = tcp_now; tp->rcv_unackwin = tcp_now; tp->t_persist_timeout = tcp_max_persist_timeout; tp->t_persist_stop = 0; tp->t_flagsext |= TF_RCVUNACK_WAITSS; tp->t_rexmtthresh = (uint8_t)tcprexmtthresh; tp->rfbuf_ts = tcp_now; tp->rfbuf_space = tcp_initial_cwnd(tp); tp->t_forced_acks = TCP_FORCED_ACKS_COUNT; /* Enable bandwidth measurement on this connection */ tp->t_flagsext |= TF_MEASURESNDBW; if (tp->t_bwmeas == NULL) { tp->t_bwmeas = tcp_bwmeas_alloc(tp); if (tp->t_bwmeas == NULL) { tp->t_flagsext &= ~TF_MEASURESNDBW; } } /* Clear time wait tailq entry */ tp->t_twentry.tqe_next = NULL; tp->t_twentry.tqe_prev = NULL; read_frandom(&random_32, sizeof(random_32)); tp->t_comp_gencnt = random_32; if (tp->t_comp_gencnt <= TCP_ACK_COMPRESSION_DUMMY) { tp->t_comp_gencnt = TCP_ACK_COMPRESSION_DUMMY + 1; } tp->t_comp_lastinc = tcp_now; if (__probable(tcp_randomize_timestamps)) { tp->t_ts_offset = random_32; } /* Initialize Accurate ECN state */ tp->t_client_accecn_state = tcp_connection_client_accurate_ecn_feature_disabled; tp->t_server_accecn_state = tcp_connection_server_accurate_ecn_feature_disabled; /* * 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 = (uint8_t)ip_defttl; inp->inp_ppcb = (caddr_t)tp; return tp; /* XXX */ } /* * 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 = tp->t_inpcb->inp_socket; #if CONFIG_DTRACE struct inpcb *inp = tp->t_inpcb; #endif if (TCPS_HAVERCVDSYN(tp->t_state)) { DTRACE_TCP4(state__change, void, NULL, struct inpcb *, inp, struct tcpcb *, tp, int32_t, TCPS_CLOSED); TCP_LOG_STATE(tp, TCPS_CLOSED); tp->t_state = TCPS_CLOSED; (void) tcp_output(tp); tcpstat.tcps_drops++; } else { tcpstat.tcps_conndrops++; } if (errno == ETIMEDOUT && tp->t_softerror) { errno = tp->t_softerror; } so->so_error = (u_short)errno; TCP_LOG_CONNECTION_SUMMARY(tp); return tcp_close(tp); } void tcp_getrt_rtt(struct tcpcb *tp, struct rtentry *rt) { u_int32_t rtt = rt->rt_rmx.rmx_rtt; int isnetlocal = (tp->t_flags & TF_LOCAL); TCP_LOG_RTM_RTT(tp, rt); if (rtt != 0 && tcp_init_rtt_from_cache != 0) { /* * XXX the lock bit for RTT indicates that the value * is also a minimum value; this is subject to time. */ if (rt->rt_rmx.rmx_locks & RTV_RTT) { tp->t_rttmin = rtt / (RTM_RTTUNIT / TCP_RETRANSHZ); } else { tp->t_rttmin = isnetlocal ? tcp_TCPTV_MIN : TCPTV_REXMTMIN; } tp->t_srtt = rtt / (RTM_RTTUNIT / (TCP_RETRANSHZ * TCP_RTT_SCALE)); tcpstat.tcps_usedrtt++; if (rt->rt_rmx.rmx_rttvar) { tp->t_rttvar = rt->rt_rmx.rmx_rttvar / (RTM_RTTUNIT / (TCP_RETRANSHZ * TCP_RTTVAR_SCALE)); tcpstat.tcps_usedrttvar++; } else { /* default variation is +- 1 rtt */ tp->t_rttvar = tp->t_srtt * TCP_RTTVAR_SCALE / TCP_RTT_SCALE; } /* * The RTO formula in the route metric case is based on: * srtt + 4 * rttvar * modulo the min, max and slop */ TCPT_RANGESET(tp->t_rxtcur, TCP_REXMTVAL(tp), tp->t_rttmin, TCPTV_REXMTMAX, TCP_ADD_REXMTSLOP(tp)); } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_srtt == 0 && tp->t_rxtshift == 0) { struct ifnet *ifp = rt->rt_ifp; if (ifp != NULL && (ifp->if_eflags & IFEF_AWDL) != 0) { /* * AWDL needs a special value for the default initial retransmission timeout */ if (tcp_awdl_rtobase > tcp_TCPTV_MIN) { tp->t_rttvar = ((tcp_awdl_rtobase - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; } else { tp->t_rttvar = ((tcp_TCPTV_MIN - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; } TCPT_RANGESET(tp->t_rxtcur, TCP_REXMTVAL(tp), tp->t_rttmin, TCPTV_REXMTMAX, TCP_ADD_REXMTSLOP(tp)); } } TCP_LOG_RTT_INFO(tp); } static inline void tcp_create_ifnet_stats_per_flow(struct tcpcb *tp, struct ifnet_stats_per_flow *ifs) { struct inpcb *inp; struct socket *so; if (tp == NULL || ifs == NULL) { return; } bzero(ifs, sizeof(*ifs)); inp = tp->t_inpcb; so = inp->inp_socket; ifs->ipv4 = (inp->inp_vflag & INP_IPV6) ? 0 : 1; ifs->local = (tp->t_flags & TF_LOCAL) ? 1 : 0; ifs->connreset = (so->so_error == ECONNRESET) ? 1 : 0; ifs->conntimeout = (so->so_error == ETIMEDOUT) ? 1 : 0; ifs->ecn_flags = tp->ecn_flags; ifs->txretransmitbytes = tp->t_stat.txretransmitbytes; ifs->rxoutoforderbytes = tp->t_stat.rxoutoforderbytes; ifs->rxmitpkts = tp->t_stat.rxmitpkts; ifs->rcvoopack = tp->t_rcvoopack; ifs->pawsdrop = tp->t_pawsdrop; ifs->sack_recovery_episodes = tp->t_sack_recovery_episode; ifs->reordered_pkts = tp->t_reordered_pkts; ifs->dsack_sent = tp->t_dsack_sent; ifs->dsack_recvd = tp->t_dsack_recvd; ifs->srtt = tp->t_srtt; ifs->rttupdated = tp->t_rttupdated; ifs->rttvar = tp->t_rttvar; ifs->rttmin = get_base_rtt(tp); if (tp->t_bwmeas != NULL && tp->t_bwmeas->bw_sndbw_max > 0) { ifs->bw_sndbw_max = tp->t_bwmeas->bw_sndbw_max; } else { ifs->bw_sndbw_max = 0; } if (tp->t_bwmeas != NULL && tp->t_bwmeas->bw_rcvbw_max > 0) { ifs->bw_rcvbw_max = tp->t_bwmeas->bw_rcvbw_max; } else { ifs->bw_rcvbw_max = 0; } ifs->bk_txpackets = so->so_tc_stats[MBUF_TC_BK].txpackets; ifs->txpackets = inp->inp_stat->txpackets; ifs->rxpackets = inp->inp_stat->rxpackets; } static inline void tcp_flow_ecn_perf_stats(struct ifnet_stats_per_flow *ifs, struct if_tcp_ecn_perf_stat *stat) { u_int64_t curval, oldval; stat->total_txpkts += ifs->txpackets; stat->total_rxpkts += ifs->rxpackets; stat->total_rxmitpkts += ifs->rxmitpkts; stat->total_oopkts += ifs->rcvoopack; stat->total_reorderpkts += (ifs->reordered_pkts + ifs->pawsdrop + ifs->dsack_sent + ifs->dsack_recvd); /* Average RTT */ curval = ifs->srtt >> TCP_RTT_SHIFT; if (curval > 0 && ifs->rttupdated >= 16) { if (stat->rtt_avg == 0) { stat->rtt_avg = curval; } else { oldval = stat->rtt_avg; stat->rtt_avg = ((oldval << 4) - oldval + curval) >> 4; } } /* RTT variance */ curval = ifs->rttvar >> TCP_RTTVAR_SHIFT; if (curval > 0 && ifs->rttupdated >= 16) { if (stat->rtt_var == 0) { stat->rtt_var = curval; } else { oldval = stat->rtt_var; stat->rtt_var = ((oldval << 4) - oldval + curval) >> 4; } } /* SACK episodes */ stat->sack_episodes += ifs->sack_recovery_episodes; if (ifs->connreset) { stat->rst_drop++; } } static inline void tcp_flow_lim_stats(struct ifnet_stats_per_flow *ifs, struct if_lim_perf_stat *stat) { u_int64_t curval, oldval; stat->lim_total_txpkts += ifs->txpackets; stat->lim_total_rxpkts += ifs->rxpackets; stat->lim_total_retxpkts += ifs->rxmitpkts; stat->lim_total_oopkts += ifs->rcvoopack; if (ifs->bw_sndbw_max > 0) { /* convert from bytes per ms to bits per second */ ifs->bw_sndbw_max *= 8000; stat->lim_ul_max_bandwidth = MAX(stat->lim_ul_max_bandwidth, ifs->bw_sndbw_max); } if (ifs->bw_rcvbw_max > 0) { /* convert from bytes per ms to bits per second */ ifs->bw_rcvbw_max *= 8000; stat->lim_dl_max_bandwidth = MAX(stat->lim_dl_max_bandwidth, ifs->bw_rcvbw_max); } /* Average RTT */ curval = ifs->srtt >> TCP_RTT_SHIFT; if (curval > 0 && ifs->rttupdated >= 16) { if (stat->lim_rtt_average == 0) { stat->lim_rtt_average = curval; } else { oldval = stat->lim_rtt_average; stat->lim_rtt_average = ((oldval << 4) - oldval + curval) >> 4; } } /* RTT variance */ curval = ifs->rttvar >> TCP_RTTVAR_SHIFT; if (curval > 0 && ifs->rttupdated >= 16) { if (stat->lim_rtt_variance == 0) { stat->lim_rtt_variance = curval; } else { oldval = stat->lim_rtt_variance; stat->lim_rtt_variance = ((oldval << 4) - oldval + curval) >> 4; } } if (stat->lim_rtt_min == 0) { stat->lim_rtt_min = ifs->rttmin; } else { stat->lim_rtt_min = MIN(stat->lim_rtt_min, ifs->rttmin); } /* connection timeouts */ stat->lim_conn_attempts++; if (ifs->conntimeout) { stat->lim_conn_timeouts++; } /* bytes sent using background delay-based algorithms */ stat->lim_bk_txpkts += ifs->bk_txpackets; } /* * Close a TCP control block: * discard all space held by the tcp * discard internet protocol block * wake up any sleepers */ struct tcpcb * tcp_close(struct tcpcb *tp) { struct inpcb *inp = tp->t_inpcb; struct socket *so = inp->inp_socket; int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; struct route *ro; struct rtentry *rt; int dosavessthresh; struct ifnet_stats_per_flow ifs; /* tcp_close was called previously, bail */ if (inp->inp_ppcb == NULL) { return NULL; } tcp_del_fsw_flow(tp); tcp_canceltimers(tp); KERNEL_DEBUG(DBG_FNC_TCP_CLOSE | DBG_FUNC_START, tp, 0, 0, 0, 0); /* * If another thread for this tcp is currently in ip (indicated by * the TF_SENDINPROG flag), defer the cleanup until after it returns * back to tcp. This is done to serialize the close until after all * pending output is finished, in order to avoid having the PCB be * detached and the cached route cleaned, only for ip to cache the * route back into the PCB again. Note that we've cleared all the * timers at this point. Set TF_CLOSING to indicate to tcp_output() * that is should call us again once it returns from ip; at that * point both flags should be cleared and we can proceed further * with the cleanup. */ if ((tp->t_flags & TF_CLOSING) || inp->inp_sndinprog_cnt > 0) { tp->t_flags |= TF_CLOSING; return NULL; } TCP_LOG_CONNECTION_SUMMARY(tp); DTRACE_TCP4(state__change, void, NULL, struct inpcb *, inp, struct tcpcb *, tp, int32_t, TCPS_CLOSED); ro = (isipv6 ? (struct route *)&inp->in6p_route : &inp->inp_route); rt = ro->ro_rt; if (rt != NULL) { RT_LOCK_SPIN(rt); } /* * If we got enough samples through the srtt filter, * save the rtt and rttvar in the routing entry. * 'Enough' is arbitrarily defined as the 16 samples. * 16 samples is enough for the srtt filter to converge * to within 5% of the correct value; fewer samples and * we could save a very bogus rtt. * * Don't update the default route's characteristics and don't * update anything that the user "locked". */ if (tp->t_rttupdated >= 16) { u_int32_t i = 0; bool log_rtt = false; if (isipv6) { struct sockaddr_in6 *sin6; if (rt == NULL) { goto no_valid_rt; } sin6 = SIN6(rt_key(rt)); if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { goto no_valid_rt; } } else if (ROUTE_UNUSABLE(ro) || SIN(rt_key(rt))->sin_addr.s_addr == INADDR_ANY) { DTRACE_TCP4(state__change, void, NULL, struct inpcb *, inp, struct tcpcb *, tp, int32_t, TCPS_CLOSED); TCP_LOG_STATE(tp, TCPS_CLOSED); tp->t_state = TCPS_CLOSED; goto no_valid_rt; } RT_LOCK_ASSERT_HELD(rt); if ((rt->rt_rmx.rmx_locks & RTV_RTT) == 0) { i = tp->t_srtt * (RTM_RTTUNIT / (TCP_RETRANSHZ * TCP_RTT_SCALE)); if (rt->rt_rmx.rmx_rtt && i) { /* * filter this update to half the old & half * the new values, converting scale. * See route.h and tcp_var.h for a * description of the scaling constants. */ rt->rt_rmx.rmx_rtt = (rt->rt_rmx.rmx_rtt + i) / 2; } else { rt->rt_rmx.rmx_rtt = i; } tcpstat.tcps_cachedrtt++; log_rtt = true; } if ((rt->rt_rmx.rmx_locks & RTV_RTTVAR) == 0) { i = tp->t_rttvar * (RTM_RTTUNIT / (TCP_RETRANSHZ * TCP_RTTVAR_SCALE)); if (rt->rt_rmx.rmx_rttvar && i) { rt->rt_rmx.rmx_rttvar = (rt->rt_rmx.rmx_rttvar + i) / 2; } else { rt->rt_rmx.rmx_rttvar = i; } tcpstat.tcps_cachedrttvar++; log_rtt = true; } if (log_rtt) { TCP_LOG_RTM_RTT(tp, rt); TCP_LOG_RTT_INFO(tp); } /* * The old comment here said: * update the pipelimit (ssthresh) if it has been updated * already or if a pipesize was specified & the threshhold * got below half the pipesize. I.e., wait for bad news * before we start updating, then update on both good * and bad news. * * But we want to save the ssthresh even if no pipesize is * specified explicitly in the route, because such * connections still have an implicit pipesize specified * by the global tcp_sendspace. In the absence of a reliable * way to calculate the pipesize, it will have to do. */ i = tp->snd_ssthresh; if (rt->rt_rmx.rmx_sendpipe != 0) { dosavessthresh = (i < rt->rt_rmx.rmx_sendpipe / 2); } else { dosavessthresh = (i < so->so_snd.sb_hiwat / 2); } if (((rt->rt_rmx.rmx_locks & RTV_SSTHRESH) == 0 && i != 0 && rt->rt_rmx.rmx_ssthresh != 0) || dosavessthresh) { /* * convert the limit from user data bytes to * packets then to packet data bytes. */ i = (i + tp->t_maxseg / 2) / tp->t_maxseg; if (i < 2) { i = 2; } i *= (u_int32_t)(tp->t_maxseg + isipv6 ? sizeof(struct ip6_hdr) + sizeof(struct tcphdr) : sizeof(struct tcpiphdr)); if (rt->rt_rmx.rmx_ssthresh) { rt->rt_rmx.rmx_ssthresh = (rt->rt_rmx.rmx_ssthresh + i) / 2; } else { rt->rt_rmx.rmx_ssthresh = i; } tcpstat.tcps_cachedssthresh++; } } /* * Mark route for deletion if no information is cached. */ if (rt != NULL && (so->so_flags & SOF_OVERFLOW)) { if (!(rt->rt_rmx.rmx_locks & RTV_RTT) && rt->rt_rmx.rmx_rtt == 0) { rt->rt_flags |= RTF_DELCLONE; } } no_valid_rt: if (rt != NULL) { RT_UNLOCK(rt); } /* free the reassembly queue, if any */ (void) tcp_freeq(tp); /* performance stats per interface */ tcp_create_ifnet_stats_per_flow(tp, &ifs); tcp_update_stats_per_flow(&ifs, inp->inp_last_outifp); tcp_free_sackholes(tp); tcp_notify_ack_free(tp); inp_decr_sndbytes_allunsent(so, tp->snd_una); if (tp->t_bwmeas != NULL) { tcp_bwmeas_free(tp); } tcp_rxtseg_clean(tp); /* Free the packet list */ if (tp->t_pktlist_head != NULL) { m_freem_list(tp->t_pktlist_head); } TCP_PKTLIST_CLEAR(tp); if (so->so_flags1 & SOF1_CACHED_IN_SOCK_LAYER) { inp->inp_saved_ppcb = (caddr_t) tp; } TCP_LOG_STATE(tp, TCPS_CLOSED); tp->t_state = TCPS_CLOSED; /* * Issue a wakeup before detach so that we don't miss * a wakeup */ sodisconnectwakeup(so); /* * Make sure to clear the TCP Keep Alive Offload as it is * ref counted on the interface */ tcp_clear_keep_alive_offload(so); /* * If this is a socket that does not want to wakeup the device * for it's traffic, the application might need to know that the * socket is closed, send a notification. */ if ((so->so_options & SO_NOWAKEFROMSLEEP) && inp->inp_state != INPCB_STATE_DEAD && !(inp->inp_flags2 & INP2_TIMEWAIT)) { socket_post_kev_msg_closed(so); } if (CC_ALGO(tp)->cleanup != NULL) { CC_ALGO(tp)->cleanup(tp); } tp->tcp_cc_index = TCP_CC_ALGO_NONE; if (TCP_USE_RLEDBAT(tp, so) && tcp_cc_rledbat.cleanup != NULL) { tcp_cc_rledbat.cleanup(tp); } /* Can happen if we close the socket before receiving the third ACK */ if ((tp->t_tfo_flags & TFO_F_COOKIE_VALID)) { OSDecrementAtomic(&tcp_tfo_halfcnt); /* Panic if something has gone terribly wrong. */ VERIFY(tcp_tfo_halfcnt >= 0); tp->t_tfo_flags &= ~TFO_F_COOKIE_VALID; } if (SOCK_CHECK_DOM(so, PF_INET6)) { in6_pcbdetach(inp); } else { in_pcbdetach(inp); } /* * Call soisdisconnected after detach because it might unlock the socket */ soisdisconnected(so); tcpstat.tcps_closed++; KERNEL_DEBUG(DBG_FNC_TCP_CLOSE | DBG_FUNC_END, tcpstat.tcps_closed, 0, 0, 0, 0); return NULL; } int tcp_freeq(struct tcpcb *tp) { struct tseg_qent *q; int rv = 0; int count = 0; while ((q = LIST_FIRST(&tp->t_segq)) != NULL) { LIST_REMOVE(q, tqe_q); tp->t_reassq_mbcnt -= _MSIZE + (q->tqe_m->m_flags & M_EXT) ? q->tqe_m->m_ext.ext_size : 0; m_freem(q->tqe_m); zfree(tcp_reass_zone, q); rv = 1; count++; } tp->t_reassqlen = 0; if (count > 0) { OSAddAtomic(-count, &tcp_reass_total_qlen); } return rv; } void tcp_drain(void) { struct inpcb *inp; struct tcpcb *tp; if (!lck_rw_try_lock_exclusive(&tcbinfo.ipi_lock)) { return; } LIST_FOREACH(inp, tcbinfo.ipi_listhead, inp_list) { if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) != WNT_STOPUSING) { socket_lock(inp->inp_socket, 1); if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) { /* lost a race, try the next one */ socket_unlock(inp->inp_socket, 1); continue; } tp = intotcpcb(inp); so_drain_extended_bk_idle(inp->inp_socket); socket_unlock(inp->inp_socket, 1); } } lck_rw_done(&tcbinfo.ipi_lock); } /* * 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 void tcp_notify(struct inpcb *inp, int error) { struct tcpcb *tp; if (inp == NULL || (inp->inp_state == INPCB_STATE_DEAD)) { return; /* pcb is gone already */ } tp = (struct tcpcb *)inp->inp_ppcb; VERIFY(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_rt) { rtfree(inp->inp_route.ro_rt); inp->inp_route.ro_rt = (struct rtentry *)NULL; } } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && tp->t_softerror) { tcp_drop(tp, error); } else { tp->t_softerror = error; } } struct bwmeas * tcp_bwmeas_alloc(struct tcpcb *tp) { struct bwmeas *elm; elm = zalloc_flags(tcp_bwmeas_zone, Z_ZERO | Z_WAITOK); elm->bw_minsizepkts = TCP_BWMEAS_BURST_MINSIZE; elm->bw_minsize = elm->bw_minsizepkts * tp->t_maxseg; return elm; } void tcp_bwmeas_free(struct tcpcb *tp) { zfree(tcp_bwmeas_zone, tp->t_bwmeas); tp->t_bwmeas = NULL; tp->t_flagsext &= ~(TF_MEASURESNDBW); } int get_tcp_inp_list(struct inpcb **inp_list, int n, inp_gen_t gencnt) { struct tcpcb *tp; struct inpcb *inp; int i = 0; LIST_FOREACH(inp, tcbinfo.ipi_listhead, inp_list) { if (inp->inp_gencnt <= gencnt && inp->inp_state != INPCB_STATE_DEAD) { inp_list[i++] = inp; } if (i >= n) { break; } } TAILQ_FOREACH(tp, &tcp_tw_tailq, t_twentry) { inp = tp->t_inpcb; if (inp->inp_gencnt <= gencnt && inp->inp_state != INPCB_STATE_DEAD) { inp_list[i++] = inp; } if (i >= n) { break; } } return i; } /* * tcpcb_to_otcpcb copies specific bits of a tcpcb to a otcpcb format. * The otcpcb data structure is passed to user space and must not change. */ static void tcpcb_to_otcpcb(struct tcpcb *tp, struct otcpcb *otp) { otp->t_segq = (uint32_t)VM_KERNEL_ADDRPERM(tp->t_segq.lh_first); otp->t_dupacks = tp->t_dupacks; otp->t_timer[TCPT_REXMT_EXT] = tp->t_timer[TCPT_REXMT]; otp->t_timer[TCPT_PERSIST_EXT] = tp->t_timer[TCPT_PERSIST]; otp->t_timer[TCPT_KEEP_EXT] = tp->t_timer[TCPT_KEEP]; otp->t_timer[TCPT_2MSL_EXT] = tp->t_timer[TCPT_2MSL]; otp->t_inpcb = (_TCPCB_PTR(struct inpcb *))VM_KERNEL_ADDRPERM(tp->t_inpcb); otp->t_state = tp->t_state; otp->t_flags = tp->t_flags; otp->t_force = (tp->t_flagsext & TF_FORCE) ? 1 : 0; otp->snd_una = tp->snd_una; otp->snd_max = tp->snd_max; otp->snd_nxt = tp->snd_nxt; otp->snd_up = tp->snd_up; otp->snd_wl1 = tp->snd_wl1; otp->snd_wl2 = tp->snd_wl2; otp->iss = tp->iss; otp->irs = tp->irs; otp->rcv_nxt = tp->rcv_nxt; otp->rcv_adv = tp->rcv_adv; otp->rcv_wnd = tp->rcv_wnd; otp->rcv_up = tp->rcv_up; otp->snd_wnd = tp->snd_wnd; otp->snd_cwnd = tp->snd_cwnd; otp->snd_ssthresh = tp->snd_ssthresh; otp->t_maxopd = tp->t_maxopd; otp->t_rcvtime = tp->t_rcvtime; otp->t_starttime = tp->t_starttime; otp->t_rtttime = tp->t_rtttime; otp->t_rtseq = tp->t_rtseq; otp->t_rxtcur = tp->t_rxtcur; otp->t_maxseg = tp->t_maxseg; otp->t_srtt = tp->t_srtt; otp->t_rttvar = tp->t_rttvar; otp->t_rxtshift = tp->t_rxtshift; otp->t_rttmin = tp->t_rttmin; otp->t_rttupdated = tp->t_rttupdated; otp->max_sndwnd = tp->max_sndwnd; otp->t_softerror = tp->t_softerror; otp->t_oobflags = tp->t_oobflags; otp->t_iobc = tp->t_iobc; otp->snd_scale = tp->snd_scale; otp->rcv_scale = tp->rcv_scale; otp->request_r_scale = tp->request_r_scale; otp->requested_s_scale = tp->requested_s_scale; otp->ts_recent = tp->ts_recent; otp->ts_recent_age = tp->ts_recent_age; otp->last_ack_sent = tp->last_ack_sent; otp->cc_send = 0; otp->cc_recv = 0; otp->snd_recover = tp->snd_recover; otp->snd_cwnd_prev = tp->snd_cwnd_prev; otp->snd_ssthresh_prev = tp->snd_ssthresh_prev; otp->t_badrxtwin = 0; } static int tcp_pcblist SYSCTL_HANDLER_ARGS { #pragma unused(oidp, arg1, arg2) int error, i = 0, n, sz; struct inpcb **inp_list; inp_gen_t gencnt; struct xinpgen xig; /* * The process of preparing the TCB list is too time-consuming and * resource-intensive to repeat twice on every request. */ lck_rw_lock_shared(&tcbinfo.ipi_lock); if (req->oldptr == USER_ADDR_NULL) { n = tcbinfo.ipi_count; req->oldidx = 2 * (sizeof(xig)) + (n + n / 8) * sizeof(struct xtcpcb); lck_rw_done(&tcbinfo.ipi_lock); return 0; } if (req->newptr != USER_ADDR_NULL) { lck_rw_done(&tcbinfo.ipi_lock); return EPERM; } /* * OK, now we're committed to doing something. */ gencnt = tcbinfo.ipi_gencnt; sz = n = tcbinfo.ipi_count; bzero(&xig, sizeof(xig)); xig.xig_len = sizeof(xig); xig.xig_count = n; xig.xig_gen = gencnt; xig.xig_sogen = so_gencnt; error = SYSCTL_OUT(req, &xig, sizeof(xig)); if (error) { lck_rw_done(&tcbinfo.ipi_lock); return error; } /* * We are done if there is no pcb */ if (n == 0) { lck_rw_done(&tcbinfo.ipi_lock); return 0; } inp_list = kalloc_type(struct inpcb *, n, Z_WAITOK); if (inp_list == NULL) { lck_rw_done(&tcbinfo.ipi_lock); return ENOMEM; } n = get_tcp_inp_list(inp_list, n, gencnt); error = 0; for (i = 0; i < n; i++) { struct xtcpcb xt; caddr_t inp_ppcb; struct inpcb *inp; inp = inp_list[i]; if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) == WNT_STOPUSING) { continue; } socket_lock(inp->inp_socket, 1); if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) { socket_unlock(inp->inp_socket, 1); continue; } if (inp->inp_gencnt > gencnt) { socket_unlock(inp->inp_socket, 1); continue; } bzero(&xt, sizeof(xt)); xt.xt_len = sizeof(xt); /* XXX should avoid extra copy */ inpcb_to_compat(inp, &xt.xt_inp); inp_ppcb = inp->inp_ppcb; if (inp_ppcb != NULL) { tcpcb_to_otcpcb((struct tcpcb *)(void *)inp_ppcb, &xt.xt_tp); } else { bzero((char *) &xt.xt_tp, sizeof(xt.xt_tp)); } if (inp->inp_socket) { sotoxsocket(inp->inp_socket, &xt.xt_socket); } socket_unlock(inp->inp_socket, 1); error = SYSCTL_OUT(req, &xt, sizeof(xt)); } 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. */ bzero(&xig, sizeof(xig)); xig.xig_len = sizeof(xig); xig.xig_gen = tcbinfo.ipi_gencnt; xig.xig_sogen = so_gencnt; xig.xig_count = tcbinfo.ipi_count; error = SYSCTL_OUT(req, &xig, sizeof(xig)); } lck_rw_done(&tcbinfo.ipi_lock); kfree_type(struct inpcb *, sz, inp_list); return error; } SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED, 0, 0, tcp_pcblist, "S,xtcpcb", "List of active TCP connections"); #if XNU_TARGET_OS_OSX static void tcpcb_to_xtcpcb64(struct tcpcb *tp, struct xtcpcb64 *otp) { otp->t_segq = (uint32_t)VM_KERNEL_ADDRPERM(tp->t_segq.lh_first); otp->t_dupacks = tp->t_dupacks; otp->t_timer[TCPT_REXMT_EXT] = tp->t_timer[TCPT_REXMT]; otp->t_timer[TCPT_PERSIST_EXT] = tp->t_timer[TCPT_PERSIST]; otp->t_timer[TCPT_KEEP_EXT] = tp->t_timer[TCPT_KEEP]; otp->t_timer[TCPT_2MSL_EXT] = tp->t_timer[TCPT_2MSL]; otp->t_state = tp->t_state; otp->t_flags = tp->t_flags; otp->t_force = (tp->t_flagsext & TF_FORCE) ? 1 : 0; otp->snd_una = tp->snd_una; otp->snd_max = tp->snd_max; otp->snd_nxt = tp->snd_nxt; otp->snd_up = tp->snd_up; otp->snd_wl1 = tp->snd_wl1; otp->snd_wl2 = tp->snd_wl2; otp->iss = tp->iss; otp->irs = tp->irs; otp->rcv_nxt = tp->rcv_nxt; otp->rcv_adv = tp->rcv_adv; otp->rcv_wnd = tp->rcv_wnd; otp->rcv_up = tp->rcv_up; otp->snd_wnd = tp->snd_wnd; otp->snd_cwnd = tp->snd_cwnd; otp->snd_ssthresh = tp->snd_ssthresh; otp->t_maxopd = tp->t_maxopd; otp->t_rcvtime = tp->t_rcvtime; otp->t_starttime = tp->t_starttime; otp->t_rtttime = tp->t_rtttime; otp->t_rtseq = tp->t_rtseq; otp->t_rxtcur = tp->t_rxtcur; otp->t_maxseg = tp->t_maxseg; otp->t_srtt = tp->t_srtt; otp->t_rttvar = tp->t_rttvar; otp->t_rxtshift = tp->t_rxtshift; otp->t_rttmin = tp->t_rttmin; otp->t_rttupdated = tp->t_rttupdated; otp->max_sndwnd = tp->max_sndwnd; otp->t_softerror = tp->t_softerror; otp->t_oobflags = tp->t_oobflags; otp->t_iobc = tp->t_iobc; otp->snd_scale = tp->snd_scale; otp->rcv_scale = tp->rcv_scale; otp->request_r_scale = tp->request_r_scale; otp->requested_s_scale = tp->requested_s_scale; otp->ts_recent = tp->ts_recent; otp->ts_recent_age = tp->ts_recent_age; otp->last_ack_sent = tp->last_ack_sent; otp->cc_send = 0; otp->cc_recv = 0; otp->snd_recover = tp->snd_recover; otp->snd_cwnd_prev = tp->snd_cwnd_prev; otp->snd_ssthresh_prev = tp->snd_ssthresh_prev; otp->t_badrxtwin = 0; } static int tcp_pcblist64 SYSCTL_HANDLER_ARGS { #pragma unused(oidp, arg1, arg2) int error, i = 0, n, sz; struct inpcb **inp_list; inp_gen_t gencnt; struct xinpgen xig; /* * The process of preparing the TCB list is too time-consuming and * resource-intensive to repeat twice on every request. */ lck_rw_lock_shared(&tcbinfo.ipi_lock); if (req->oldptr == USER_ADDR_NULL) { n = tcbinfo.ipi_count; req->oldidx = 2 * (sizeof(xig)) + (n + n / 8) * sizeof(struct xtcpcb64); lck_rw_done(&tcbinfo.ipi_lock); return 0; } if (req->newptr != USER_ADDR_NULL) { lck_rw_done(&tcbinfo.ipi_lock); return EPERM; } /* * OK, now we're committed to doing something. */ gencnt = tcbinfo.ipi_gencnt; sz = n = tcbinfo.ipi_count; bzero(&xig, sizeof(xig)); xig.xig_len = sizeof(xig); xig.xig_count = n; xig.xig_gen = gencnt; xig.xig_sogen = so_gencnt; error = SYSCTL_OUT(req, &xig, sizeof(xig)); if (error) { lck_rw_done(&tcbinfo.ipi_lock); return error; } /* * We are done if there is no pcb */ if (n == 0) { lck_rw_done(&tcbinfo.ipi_lock); return 0; } inp_list = kalloc_type(struct inpcb *, n, Z_WAITOK); if (inp_list == NULL) { lck_rw_done(&tcbinfo.ipi_lock); return ENOMEM; } n = get_tcp_inp_list(inp_list, n, gencnt); error = 0; for (i = 0; i < n; i++) { struct xtcpcb64 xt; struct inpcb *inp; inp = inp_list[i]; if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) == WNT_STOPUSING) { continue; } socket_lock(inp->inp_socket, 1); if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) { socket_unlock(inp->inp_socket, 1); continue; } if (inp->inp_gencnt > gencnt) { socket_unlock(inp->inp_socket, 1); continue; } bzero(&xt, sizeof(xt)); xt.xt_len = sizeof(xt); inpcb_to_xinpcb64(inp, &xt.xt_inpcb); xt.xt_inpcb.inp_ppcb = (uint64_t)VM_KERNEL_ADDRPERM(inp->inp_ppcb); if (inp->inp_ppcb != NULL) { tcpcb_to_xtcpcb64((struct tcpcb *)inp->inp_ppcb, &xt); } if (inp->inp_socket) { sotoxsocket64(inp->inp_socket, &xt.xt_inpcb.xi_socket); } socket_unlock(inp->inp_socket, 1); error = SYSCTL_OUT(req, &xt, sizeof(xt)); } 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. */ bzero(&xig, sizeof(xig)); xig.xig_len = sizeof(xig); xig.xig_gen = tcbinfo.ipi_gencnt; xig.xig_sogen = so_gencnt; xig.xig_count = tcbinfo.ipi_count; error = SYSCTL_OUT(req, &xig, sizeof(xig)); } lck_rw_done(&tcbinfo.ipi_lock); kfree_type(struct inpcb *, sz, inp_list); return error; } SYSCTL_PROC(_net_inet_tcp, OID_AUTO, pcblist64, CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED, 0, 0, tcp_pcblist64, "S,xtcpcb64", "List of active TCP connections"); #endif /* XNU_TARGET_OS_OSX */ static int tcp_pcblist_n SYSCTL_HANDLER_ARGS { #pragma unused(oidp, arg1, arg2) int error = 0; error = get_pcblist_n(IPPROTO_TCP, req, &tcbinfo); return error; } SYSCTL_PROC(_net_inet_tcp, OID_AUTO, pcblist_n, CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED, 0, 0, tcp_pcblist_n, "S,xtcpcb_n", "List of active TCP connections"); static int tcp_progress_indicators SYSCTL_HANDLER_ARGS { #pragma unused(oidp, arg1, arg2) return ntstat_tcp_progress_indicators(req); } SYSCTL_PROC(_net_inet_tcp, OID_AUTO, progress, CTLTYPE_STRUCT | CTLFLAG_RW | CTLFLAG_LOCKED | CTLFLAG_ANYBODY, 0, 0, tcp_progress_indicators, "S", "Various items that indicate the current state of progress on the link"); static int tcp_progress_probe_enable SYSCTL_HANDLER_ARGS { #pragma unused(oidp, arg1, arg2) return ntstat_tcp_progress_enable(req); } SYSCTL_PROC(_net_inet_tcp, OID_AUTO, progress_enable, CTLTYPE_STRUCT | CTLFLAG_RW | CTLFLAG_LOCKED | CTLFLAG_ANYBODY, 0, 0, tcp_progress_probe_enable, "S", "Enable/disable TCP keepalive probing on the specified link(s)"); __private_extern__ void tcp_get_ports_used(ifnet_t ifp, int protocol, uint32_t flags, bitstr_t *bitfield) { inpcb_get_ports_used(ifp, protocol, flags, bitfield, &tcbinfo); } __private_extern__ uint32_t tcp_count_opportunistic(unsigned int ifindex, u_int32_t flags) { return inpcb_count_opportunistic(ifindex, &tcbinfo, flags); } __private_extern__ uint32_t tcp_find_anypcb_byaddr(struct ifaddr *ifa) { #if SKYWALK if (netns_is_enabled()) { return netns_find_anyres_byaddr(ifa, IPPROTO_TCP); } else #endif /* SKYWALK */ return inpcb_find_anypcb_byaddr(ifa, &tcbinfo); } static void tcp_handle_msgsize(struct ip *ip, struct inpcb *inp) { struct rtentry *rt = NULL; u_short ifscope = IFSCOPE_NONE; int mtu; struct sockaddr_in icmpsrc = { .sin_len = sizeof(struct sockaddr_in), .sin_family = AF_INET, .sin_port = 0, .sin_addr = { .s_addr = 0 }, .sin_zero = { 0, 0, 0, 0, 0, 0, 0, 0 } }; struct icmp *icp = NULL; icp = (struct icmp *)(void *) ((caddr_t)ip - offsetof(struct icmp, icmp_ip)); icmpsrc.sin_addr = icp->icmp_ip.ip_dst; /* * MTU discovery: * If we got a needfrag and there is a host route to the * original destination, and the MTU is not locked, then * set the MTU in the route to the suggested new value * (if given) and then notify as usual. The ULPs will * notice that the MTU has changed and adapt accordingly. * If no new MTU was suggested, then we guess a new one * less than the current value. If the new MTU is * unreasonably small (defined by sysctl tcp_minmss), then * we reset the MTU to the interface value and enable the * lock bit, indicating that we are no longer doing MTU * discovery. */ if (ROUTE_UNUSABLE(&(inp->inp_route)) == false) { rt = inp->inp_route.ro_rt; } /* * icmp6_mtudisc_update scopes the routing lookup * to the incoming interface (delivered from mbuf * packet header. * That is mostly ok but for asymmetric networks * that may be an issue. * Frag needed OR Packet too big really communicates * MTU for the out data path. * Take the interface scope from cached route or * the last outgoing interface from inp */ if (rt != NULL) { ifscope = (rt->rt_ifp != NULL) ? rt->rt_ifp->if_index : IFSCOPE_NONE; } else { ifscope = (inp->inp_last_outifp != NULL) ? inp->inp_last_outifp->if_index : IFSCOPE_NONE; } if ((rt == NULL) || !(rt->rt_flags & RTF_HOST) || (rt->rt_flags & (RTF_CLONING | RTF_PRCLONING))) { rt = rtalloc1_scoped(SA(&icmpsrc), 0, RTF_CLONING | RTF_PRCLONING, ifscope); } else if (rt) { RT_LOCK(rt); rtref(rt); RT_UNLOCK(rt); } if (rt != NULL) { RT_LOCK(rt); if ((rt->rt_flags & RTF_HOST) && !(rt->rt_rmx.rmx_locks & RTV_MTU)) { mtu = ntohs(icp->icmp_nextmtu); /* * XXX Stock BSD has changed the following * to compare with icp->icmp_ip.ip_len * to converge faster when sent packet * < route's MTU. We may want to adopt * that change. */ if (mtu == 0) { mtu = ip_next_mtu(rt->rt_rmx. rmx_mtu, 1); } #if DEBUG_MTUDISC printf("MTU for %s reduced to %d\n", inet_ntop(AF_INET, &icmpsrc.sin_addr, ipv4str, sizeof(ipv4str)), mtu); #endif if (mtu < max(296, (tcp_minmss + sizeof(struct tcpiphdr)))) { rt->rt_rmx.rmx_locks |= RTV_MTU; } else if (rt->rt_rmx.rmx_mtu > mtu) { rt->rt_rmx.rmx_mtu = mtu; } } RT_UNLOCK(rt); rtfree(rt); } } void tcp_ctlinput(int cmd, struct sockaddr *sa, void *vip, __unused struct ifnet *ifp) { tcp_seq icmp_tcp_seq; struct ipctlparam *ctl_param = vip; struct ip *ip = NULL; struct mbuf *m = NULL; struct in_addr faddr; struct inpcb *inp; struct tcpcb *tp; struct tcphdr *th; struct icmp *icp; size_t off; #if SKYWALK union sockaddr_in_4_6 sock_laddr; struct protoctl_ev_val prctl_ev_val; #endif /* SKYWALK */ void (*notify)(struct inpcb *, int) = tcp_notify; if (ctl_param != NULL) { ip = ctl_param->ipc_icmp_ip; icp = ctl_param->ipc_icmp; m = ctl_param->ipc_m; off = ctl_param->ipc_off; } else { ip = NULL; icp = NULL; m = NULL; off = 0; } faddr = SIN(sa)->sin_addr; if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) { return; } if ((unsigned)cmd >= PRC_NCMDS) { return; } /* Source quench is deprecated */ if (cmd == PRC_QUENCH) { return; } if (cmd == PRC_MSGSIZE) { notify = tcp_mtudisc; } else if (icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || cmd == PRC_UNREACH_PORT || cmd == PRC_UNREACH_PROTOCOL || cmd == PRC_TIMXCEED_INTRANS) && ip) { notify = tcp_drop_syn_sent; } /* * Hostdead is ugly because it goes linearly through all PCBs. * XXX: We never get this from ICMP, otherwise it makes an * excellent DoS attack on machines with many connections. */ else if (cmd == PRC_HOSTDEAD) { ip = NULL; } else if (inetctlerrmap[cmd] == 0 && !PRC_IS_REDIRECT(cmd)) { return; } #if SKYWALK bzero(&prctl_ev_val, sizeof(prctl_ev_val)); bzero(&sock_laddr, sizeof(sock_laddr)); #endif /* SKYWALK */ if (ip == NULL) { in_pcbnotifyall(&tcbinfo, faddr, inetctlerrmap[cmd], notify); #if SKYWALK protoctl_event_enqueue_nwk_wq_entry(ifp, NULL, sa, 0, 0, IPPROTO_TCP, cmd, NULL); #endif /* SKYWALK */ return; } /* Check if we can safely get the sport, dport and the sequence number from the tcp header. */ if (m == NULL || (m->m_len < off + (sizeof(unsigned short) + sizeof(unsigned short) + sizeof(tcp_seq)))) { /* Insufficient length */ return; } th = (struct tcphdr*)(void*)(mtod(m, uint8_t*) + off); icmp_tcp_seq = ntohl(th->th_seq); inp = in_pcblookup_hash(&tcbinfo, faddr, th->th_dport, ip->ip_src, th->th_sport, 0, NULL); if (inp == NULL || inp->inp_socket == NULL) { #if SKYWALK if (cmd == PRC_MSGSIZE) { prctl_ev_val.val = ntohs(icp->icmp_nextmtu); } prctl_ev_val.tcp_seq_number = icmp_tcp_seq; sock_laddr.sin.sin_family = AF_INET; sock_laddr.sin.sin_len = sizeof(sock_laddr.sin); sock_laddr.sin.sin_addr = ip->ip_src; protoctl_event_enqueue_nwk_wq_entry(ifp, SA(&sock_laddr), sa, th->th_sport, th->th_dport, IPPROTO_TCP, cmd, &prctl_ev_val); #endif /* SKYWALK */ return; } socket_lock(inp->inp_socket, 1); if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) { socket_unlock(inp->inp_socket, 1); return; } if (PRC_IS_REDIRECT(cmd)) { /* signal EHOSTDOWN, as it flushes the cached route */ (*notify)(inp, EHOSTDOWN); } else { tp = intotcpcb(inp); if (SEQ_GEQ(icmp_tcp_seq, tp->snd_una) && SEQ_LT(icmp_tcp_seq, tp->snd_max)) { if (cmd == PRC_MSGSIZE) { tcp_handle_msgsize(ip, inp); } (*notify)(inp, inetctlerrmap[cmd]); } } socket_unlock(inp->inp_socket, 1); } void tcp6_ctlinput(int cmd, struct sockaddr *sa, void *d, __unused struct ifnet *ifp) { tcp_seq icmp_tcp_seq; struct in6_addr *dst; void (*notify)(struct inpcb *, int) = tcp_notify; struct ip6_hdr *ip6; struct mbuf *m; struct inpcb *inp; struct tcpcb *tp; struct icmp6_hdr *icmp6; struct ip6ctlparam *ip6cp = NULL; const struct sockaddr_in6 *sa6_src = NULL; unsigned int mtu; unsigned int off; struct tcp_ports { uint16_t th_sport; uint16_t th_dport; } t_ports; #if SKYWALK union sockaddr_in_4_6 sock_laddr; struct protoctl_ev_val prctl_ev_val; #endif /* SKYWALK */ if (sa->sa_family != AF_INET6 || sa->sa_len != sizeof(struct sockaddr_in6)) { return; } /* Source quench is deprecated */ if (cmd == PRC_QUENCH) { return; } if ((unsigned)cmd >= PRC_NCMDS) { return; } /* if the parameter is from icmp6, decode it. */ if (d != NULL) { ip6cp = (struct ip6ctlparam *)d; icmp6 = ip6cp->ip6c_icmp6; m = ip6cp->ip6c_m; ip6 = ip6cp->ip6c_ip6; off = ip6cp->ip6c_off; sa6_src = ip6cp->ip6c_src; dst = ip6cp->ip6c_finaldst; } else { m = NULL; ip6 = NULL; off = 0; /* fool gcc */ sa6_src = &sa6_any; dst = NULL; } if (cmd == PRC_MSGSIZE) { notify = tcp_mtudisc; } else if (icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || cmd == PRC_UNREACH_PORT || cmd == PRC_TIMXCEED_INTRANS) && ip6 != NULL) { notify = tcp_drop_syn_sent; } /* * Hostdead is ugly because it goes linearly through all PCBs. * XXX: We never get this from ICMP, otherwise it makes an * excellent DoS attack on machines with many connections. */ else if (cmd == PRC_HOSTDEAD) { ip6 = NULL; } else if (inet6ctlerrmap[cmd] == 0 && !PRC_IS_REDIRECT(cmd)) { return; } #if SKYWALK bzero(&prctl_ev_val, sizeof(prctl_ev_val)); bzero(&sock_laddr, sizeof(sock_laddr)); #endif /* SKYWALK */ if (ip6 == NULL) { in6_pcbnotify(&tcbinfo, sa, 0, SA(sa6_src), 0, cmd, NULL, notify); #if SKYWALK protoctl_event_enqueue_nwk_wq_entry(ifp, NULL, sa, 0, 0, IPPROTO_TCP, cmd, NULL); #endif /* SKYWALK */ return; } /* 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); off += sizeof(struct tcp_ports); if (m->m_pkthdr.len < (int32_t) (off + sizeof(tcp_seq))) { return; } m_copydata(m, off, sizeof(tcp_seq), (caddr_t)&icmp_tcp_seq); icmp_tcp_seq = ntohl(icmp_tcp_seq); if (cmd == PRC_MSGSIZE) { 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; } } inp = in6_pcblookup_hash(&tcbinfo, &ip6->ip6_dst, t_ports.th_dport, ip6_input_getdstifscope(m), &ip6->ip6_src, t_ports.th_sport, ip6_input_getsrcifscope(m), 0, NULL); if (inp == NULL || inp->inp_socket == NULL) { #if SKYWALK if (cmd == PRC_MSGSIZE) { prctl_ev_val.val = mtu; } prctl_ev_val.tcp_seq_number = icmp_tcp_seq; sock_laddr.sin6.sin6_family = AF_INET6; sock_laddr.sin6.sin6_len = sizeof(sock_laddr.sin6); sock_laddr.sin6.sin6_addr = ip6->ip6_src; protoctl_event_enqueue_nwk_wq_entry(ifp, SA(&sock_laddr), sa, t_ports.th_sport, t_ports.th_dport, IPPROTO_TCP, cmd, &prctl_ev_val); #endif /* SKYWALK */ return; } socket_lock(inp->inp_socket, 1); if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) { socket_unlock(inp->inp_socket, 1); return; } if (PRC_IS_REDIRECT(cmd)) { /* signal EHOSTDOWN, as it flushes the cached route */ (*notify)(inp, EHOSTDOWN); } else { tp = intotcpcb(inp); if (SEQ_GEQ(icmp_tcp_seq, tp->snd_una) && SEQ_LT(icmp_tcp_seq, tp->snd_max)) { if (cmd == PRC_MSGSIZE) { /* * 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))) { (*notify)(inp, inetctlerrmap[cmd]); } } else { (*notify)(inp, inetctlerrmap[cmd]); } } } socket_unlock(inp->inp_socket, 1); } /* * 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. * * The ISNs in SYN-ACK packets have no monotonicity requirement, * and should be as unpredictable as possible to avoid the possibility * of spoofing and/or connection hijacking. To satisfy this * requirement, SYN-ACK ISNs are generated via the arc4random() * function. If exact RFC 1948 compliance is requested via sysctl, * these ISNs will be generated just like those in SYN packets. * * 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 to generate sequence numbers. * * For more information on the theory of operation, please see * RFC 1948. * * 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. * * Two sysctls control the generation of ISNs: * * 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. * * net.inet.tcp.strict_rfc1948 controls whether RFC 1948 is followed * strictly. When strict compliance is requested, reseeding is * disabled and SYN-ACKs will be generated in the same manner as * SYNs. Strict mode is disabled by default. * */ #define ISN_BYTES_PER_SECOND 1048576 tcp_seq tcp_new_isn(struct tcpcb *tp) { u_int32_t md5_buffer[4]; tcp_seq new_isn; struct timeval timenow; u_char isn_secret[32]; long isn_last_reseed = 0; MD5_CTX isn_ctx; /* Use arc4random for SYN-ACKs when not in exact RFC1948 mode. */ if (((tp->t_state == TCPS_LISTEN) || (tp->t_state == TCPS_TIME_WAIT)) && tcp_strict_rfc1948 == 0) #ifdef __APPLE__ { return RandomULong(); } #else { return arc4random(); } #endif getmicrotime(&timenow); /* Seed if this is the first use, reseed if requested. */ if ((isn_last_reseed == 0) || ((tcp_strict_rfc1948 == 0) && (tcp_isn_reseed_interval > 0) && (((u_int)isn_last_reseed + (u_int)tcp_isn_reseed_interval * hz) < (u_int)timenow.tv_sec))) { #ifdef __APPLE__ read_frandom(&isn_secret, sizeof(isn_secret)); #else read_random_unlimited(&isn_secret, sizeof(isn_secret)); #endif isn_last_reseed = timenow.tv_sec; } /* Compute the md5 hash and return the ISN. */ MD5Init(&isn_ctx); MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_fport, sizeof(u_short)); MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_lport, sizeof(u_short)); if ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0) { MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_faddr, sizeof(struct in6_addr)); MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_laddr, sizeof(struct in6_addr)); } else { MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_faddr, sizeof(struct in_addr)); MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_laddr, sizeof(struct in_addr)); } MD5Update(&isn_ctx, (u_char *) &isn_secret, sizeof(isn_secret)); MD5Final((u_char *) &md5_buffer, &isn_ctx); new_isn = (tcp_seq) md5_buffer[0]; new_isn += timenow.tv_sec * (ISN_BYTES_PER_SECOND / hz); 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. */ void tcp_drop_syn_sent(struct inpcb *inp, int errno) { struct tcpcb *tp = intotcpcb(inp); if (tp && tp->t_state == TCPS_SYN_SENT) { tcp_drop(tp, errno); } } /* * When `need fragmentation' ICMP is received, update our idea of the MSS * based on the new value in the route. 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. */ void tcp_mtudisc(struct inpcb *inp, __unused int errno) { struct tcpcb *tp = intotcpcb(inp); struct rtentry *rt; struct socket *so = inp->inp_socket; int mss; u_int32_t mtu; u_int32_t protoHdrOverhead = sizeof(struct tcpiphdr); int isipv6 = (tp->t_inpcb->inp_vflag & INP_IPV6) != 0; /* * Nothing left to send after the socket is defunct or TCP is in the closed state */ if ((so->so_state & SS_DEFUNCT) || (tp != NULL && tp->t_state == TCPS_CLOSED)) { return; } if (isipv6) { protoHdrOverhead = sizeof(struct ip6_hdr) + sizeof(struct tcphdr); } if (tp != NULL) { if (isipv6) { rt = tcp_rtlookup6(inp, IFSCOPE_NONE); } else { rt = tcp_rtlookup(inp, IFSCOPE_NONE); } if (!rt || !rt->rt_rmx.rmx_mtu) { tp->t_maxopd = tp->t_maxseg = isipv6 ? tcp_v6mssdflt : tcp_mssdflt; /* Route locked during lookup above */ if (rt != NULL) { RT_UNLOCK(rt); } return; } mtu = rt->rt_rmx.rmx_mtu; /* Route locked during lookup above */ RT_UNLOCK(rt); #if NECP // Adjust MTU if necessary. mtu = necp_socket_get_effective_mtu(inp, mtu); #endif /* NECP */ mss = mtu - protoHdrOverhead; if (tp->t_maxopd) { mss = min(mss, tp->t_maxopd); } /* * XXX - The above conditional probably violates the TCP * spec. The problem is that, since we don't know the * other end's MSS, we are supposed to use a conservative * default. But, if we do that, then MTU discovery will * never actually take place, because the conservative * default is much less than the MTUs typically seen * on the Internet today. For the moment, we'll sweep * this under the carpet. * * The conservative default might not actually be a problem * if the only case this occurs is when sending an initial * SYN with options and data to a host we've never talked * to before. Then, they will reply with an MSS value which * will get recorded and the new parameters should get * recomputed. For Further Study. */ if (tp->t_maxopd <= mss) { return; } tp->t_maxopd = mss; if ((tp->t_flags & (TF_REQ_TSTMP | TF_NOOPT)) == TF_REQ_TSTMP && (tp->t_flags & TF_RCVD_TSTMP) == TF_RCVD_TSTMP) { mss -= TCPOLEN_TSTAMP_APPA; } #if MPTCP mss -= mptcp_adj_mss(tp, TRUE); #endif if (so->so_snd.sb_hiwat < mss) { mss = so->so_snd.sb_hiwat; } tp->t_maxseg = mss; ASSERT(tp->t_maxseg); /* * Reset the slow-start flight size as it may depends on the * new MSS */ if (CC_ALGO(tp)->cwnd_init != NULL) { CC_ALGO(tp)->cwnd_init(tp); } if (TCP_USE_RLEDBAT(tp, so) && tcp_cc_rledbat.rwnd_init != NULL) { tcp_cc_rledbat.rwnd_init(tp); } tcpstat.tcps_mturesent++; tp->t_rtttime = 0; tp->snd_nxt = tp->snd_una; tcp_output(tp); } } /* * Look-up the routing entry to the peer of this inpcb. If no route * is found and it cannot be allocated the return NULL. This routine * is called by TCP routines that access the rmx structure and by tcp_mss * to get the interface MTU. If a route is found, this routine will * hold the rtentry lock; the caller is responsible for unlocking. */ struct rtentry * tcp_rtlookup(struct inpcb *inp, unsigned int input_ifscope) { struct route *ro; struct rtentry *rt; struct tcpcb *tp; LCK_MTX_ASSERT(rnh_lock, LCK_MTX_ASSERT_NOTOWNED); ro = &inp->inp_route; if ((rt = ro->ro_rt) != NULL) { RT_LOCK(rt); } if (ROUTE_UNUSABLE(ro)) { if (rt != NULL) { RT_UNLOCK(rt); rt = NULL; } ROUTE_RELEASE(ro); /* No route yet, so try to acquire one */ if (inp->inp_faddr.s_addr != INADDR_ANY) { unsigned int ifscope; ro->ro_dst.sa_family = AF_INET; ro->ro_dst.sa_len = sizeof(struct sockaddr_in); SIN(&ro->ro_dst)->sin_addr = inp->inp_faddr; /* * If the socket was bound to an interface, then * the bound-to-interface takes precedence over * the inbound interface passed in by the caller * (if we get here as part of the output path then * input_ifscope is IFSCOPE_NONE). */ ifscope = (inp->inp_flags & INP_BOUND_IF) ? inp->inp_boundifp->if_index : input_ifscope; rtalloc_scoped(ro, ifscope); if ((rt = ro->ro_rt) != NULL) { RT_LOCK(rt); } } } if (rt != NULL) { RT_LOCK_ASSERT_HELD(rt); } /* * Update MTU discovery determination. Don't do it if: * 1) it is disabled via the sysctl * 2) the route isn't up * 3) the MTU is locked (if it is, then discovery has been * disabled) */ tp = intotcpcb(inp); if (!path_mtu_discovery || ((rt != NULL) && (!(rt->rt_flags & RTF_UP) || (rt->rt_rmx.rmx_locks & RTV_MTU)))) { tp->t_flags &= ~TF_PMTUD; } else { tp->t_flags |= TF_PMTUD; } if (rt != NULL && rt->rt_ifp != NULL) { somultipages(inp->inp_socket, (rt->rt_ifp->if_hwassist & IFNET_MULTIPAGES)); tcp_set_tso(tp, rt->rt_ifp); soif2kcl(inp->inp_socket, (rt->rt_ifp->if_eflags & IFEF_2KCL)); tcp_set_ecn(tp, rt->rt_ifp); if (inp->inp_last_outifp == NULL) { inp->inp_last_outifp = rt->rt_ifp; #if SKYWALK if (NETNS_TOKEN_VALID(&inp->inp_netns_token)) { netns_set_ifnet(&inp->inp_netns_token, inp->inp_last_outifp); } #endif /* SKYWALK */ } } /* Note if the peer is local */ if (rt != NULL && !(rt->rt_ifp->if_flags & IFF_POINTOPOINT) && (rt->rt_gateway->sa_family == AF_LINK || rt->rt_ifp->if_flags & IFF_LOOPBACK || in_localaddr(inp->inp_faddr))) { tp->t_flags |= TF_LOCAL; } /* * Caller needs to call RT_UNLOCK(rt). */ return rt; } struct rtentry * tcp_rtlookup6(struct inpcb *inp, unsigned int input_ifscope) { struct route_in6 *ro6; struct rtentry *rt; struct tcpcb *tp; LCK_MTX_ASSERT(rnh_lock, LCK_MTX_ASSERT_NOTOWNED); ro6 = &inp->in6p_route; if ((rt = ro6->ro_rt) != NULL) { RT_LOCK(rt); } if (ROUTE_UNUSABLE(ro6)) { if (rt != NULL) { RT_UNLOCK(rt); rt = NULL; } ROUTE_RELEASE(ro6); /* No route yet, so try to acquire one */ if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) { struct sockaddr_in6 *dst6; unsigned int ifscope; dst6 = SIN6(&ro6->ro_dst); dst6->sin6_family = AF_INET6; dst6->sin6_len = sizeof(*dst6); dst6->sin6_addr = inp->in6p_faddr; /* * If the socket was bound to an interface, then * the bound-to-interface takes precedence over * the inbound interface passed in by the caller * (if we get here as part of the output path then * input_ifscope is IFSCOPE_NONE). */ ifscope = (inp->inp_flags & INP_BOUND_IF) ? inp->inp_boundifp->if_index : input_ifscope; rtalloc_scoped((struct route *)ro6, ifscope); if ((rt = ro6->ro_rt) != NULL) { RT_LOCK(rt); } } } if (rt != NULL) { RT_LOCK_ASSERT_HELD(rt); } /* * Update path MTU Discovery determination * while looking up the route: * 1) we have a valid route to the destination * 2) the MTU is not locked (if it is, then discovery has been * disabled) */ tp = intotcpcb(inp); /* * Update MTU discovery determination. Don't do it if: * 1) it is disabled via the sysctl * 2) the route isn't up * 3) the MTU is locked (if it is, then discovery has been * disabled) */ if (!path_mtu_discovery || ((rt != NULL) && (!(rt->rt_flags & RTF_UP) || (rt->rt_rmx.rmx_locks & RTV_MTU)))) { tp->t_flags &= ~TF_PMTUD; } else { tp->t_flags |= TF_PMTUD; } if (rt != NULL && rt->rt_ifp != NULL) { somultipages(inp->inp_socket, (rt->rt_ifp->if_hwassist & IFNET_MULTIPAGES)); tcp_set_tso(tp, rt->rt_ifp); soif2kcl(inp->inp_socket, (rt->rt_ifp->if_eflags & IFEF_2KCL)); tcp_set_ecn(tp, rt->rt_ifp); if (inp->inp_last_outifp == NULL) { inp->inp_last_outifp = rt->rt_ifp; #if SKYWALK if (NETNS_TOKEN_VALID(&inp->inp_netns_token)) { netns_set_ifnet(&inp->inp_netns_token, inp->inp_last_outifp); } #endif /* SKYWALK */ } /* Note if the peer is local */ if (!(rt->rt_ifp->if_flags & IFF_POINTOPOINT) && (IN6_IS_ADDR_LOOPBACK(&inp->in6p_faddr) || IN6_IS_ADDR_LINKLOCAL(&inp->in6p_faddr) || rt->rt_gateway->sa_family == AF_LINK || in6_localaddr(&inp->in6p_faddr))) { tp->t_flags |= TF_LOCAL; } } /* * Caller needs to call RT_UNLOCK(rt). */ return rt; } #if IPSEC /* compute ESP/AH header size for TCP, including outer IP header. */ size_t ipsec_hdrsiz_tcp(struct tcpcb *tp) { struct inpcb *inp; struct mbuf *m; size_t hdrsiz; struct ip *ip; struct ip6_hdr *ip6 = NULL; struct tcphdr *th; if ((tp == NULL) || ((inp = tp->t_inpcb) == NULL)) { return 0; } MGETHDR(m, M_DONTWAIT, MT_DATA); /* MAC-OK */ if (!m) { return 0; } if ((inp->inp_vflag & INP_IPV6) != 0) { ip6 = mtod(m, struct ip6_hdr *); th = (struct tcphdr *)(void *)(ip6 + 1); m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + sizeof(struct tcphdr); tcp_fillheaders(m, tp, ip6, th); hdrsiz = ipsec6_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); } else { ip = mtod(m, struct ip *); th = (struct tcphdr *)(ip + 1); m->m_pkthdr.len = m->m_len = sizeof(struct tcpiphdr); tcp_fillheaders(m, tp, ip, th); hdrsiz = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); } m_free(m); return hdrsiz; } #endif /* IPSEC */ int tcp_lock(struct socket *so, int refcount, void *lr) { void *lr_saved; if (lr == NULL) { lr_saved = __builtin_return_address(0); } else { lr_saved = lr; } retry: if (so->so_pcb != NULL) { if (so->so_flags & SOF_MP_SUBFLOW) { struct mptcb *mp_tp = tptomptp(sototcpcb(so)); struct socket *mp_so = mptetoso(mp_tp->mpt_mpte); socket_lock(mp_so, refcount); /* * Check if we became non-MPTCP while waiting for the lock. * If yes, we have to retry to grab the right lock. */ if (!(so->so_flags & SOF_MP_SUBFLOW)) { socket_unlock(mp_so, refcount); goto retry; } } else { lck_mtx_lock(&((struct inpcb *)so->so_pcb)->inpcb_mtx); if (so->so_flags & SOF_MP_SUBFLOW) { /* * While waiting for the lock, we might have * become MPTCP-enabled (see mptcp_subflow_socreate). */ lck_mtx_unlock(&((struct inpcb *)so->so_pcb)->inpcb_mtx); goto retry; } } } else { panic("tcp_lock: so=%p NO PCB! lr=%p lrh= %s", so, lr_saved, solockhistory_nr(so)); /* NOTREACHED */ } if (so->so_usecount < 0) { panic("tcp_lock: so=%p so_pcb=%p lr=%p ref=%x lrh= %s", so, so->so_pcb, lr_saved, so->so_usecount, solockhistory_nr(so)); /* NOTREACHED */ } if (refcount) { so->so_usecount++; } so->lock_lr[so->next_lock_lr] = lr_saved; so->next_lock_lr = (so->next_lock_lr + 1) % SO_LCKDBG_MAX; return 0; } int tcp_unlock(struct socket *so, int refcount, void *lr) { void *lr_saved; if (lr == NULL) { lr_saved = __builtin_return_address(0); } else { lr_saved = lr; } #ifdef MORE_TCPLOCK_DEBUG printf("tcp_unlock: so=0x%llx sopcb=0x%llx lock=0x%llx ref=%x " "lr=0x%llx\n", (uint64_t)VM_KERNEL_ADDRPERM(so), (uint64_t)VM_KERNEL_ADDRPERM(so->so_pcb), (uint64_t)VM_KERNEL_ADDRPERM(&(sotoinpcb(so)->inpcb_mtx)), so->so_usecount, (uint64_t)VM_KERNEL_ADDRPERM(lr_saved)); #endif if (refcount) { so->so_usecount--; } if (so->so_usecount < 0) { panic("tcp_unlock: so=%p usecount=%x lrh= %s", so, so->so_usecount, solockhistory_nr(so)); /* NOTREACHED */ } if (so->so_pcb == NULL) { panic("tcp_unlock: so=%p NO PCB usecount=%x lr=%p lrh= %s", so, so->so_usecount, lr_saved, solockhistory_nr(so)); /* NOTREACHED */ } else { so->unlock_lr[so->next_unlock_lr] = lr_saved; so->next_unlock_lr = (so->next_unlock_lr + 1) % SO_LCKDBG_MAX; if (so->so_flags & SOF_MP_SUBFLOW) { struct mptcb *mp_tp = tptomptp(sototcpcb(so)); struct socket *mp_so = mptetoso(mp_tp->mpt_mpte); socket_lock_assert_owned(mp_so); socket_unlock(mp_so, refcount); } else { LCK_MTX_ASSERT(&((struct inpcb *)so->so_pcb)->inpcb_mtx, LCK_MTX_ASSERT_OWNED); lck_mtx_unlock(&((struct inpcb *)so->so_pcb)->inpcb_mtx); } } return 0; } lck_mtx_t * tcp_getlock(struct socket *so, int flags) { struct inpcb *inp = sotoinpcb(so); if (so->so_pcb) { if (so->so_usecount < 0) { panic("tcp_getlock: so=%p usecount=%x lrh= %s", so, so->so_usecount, solockhistory_nr(so)); } if (so->so_flags & SOF_MP_SUBFLOW) { struct mptcb *mp_tp = tptomptp(sototcpcb(so)); struct socket *mp_so = mptetoso(mp_tp->mpt_mpte); return mp_so->so_proto->pr_getlock(mp_so, flags); } else { return &inp->inpcb_mtx; } } else { panic("tcp_getlock: so=%p NULL so_pcb %s", so, solockhistory_nr(so)); return so->so_proto->pr_domain->dom_mtx; } } /* * Determine if we can grow the recieve socket buffer to avoid sending * a zero window update to the peer. We allow even socket buffers that * have fixed size (set by the application) to grow if the resource * constraints are met. They will also be trimmed after the application * reads data. */ static void tcp_sbrcv_grow_rwin(struct tcpcb *tp, struct sockbuf *sb) { u_int32_t rcvbufinc = tp->t_maxseg << 4; u_int32_t rcvbuf = sb->sb_hiwat; struct socket *so = tp->t_inpcb->inp_socket; if (tcp_recv_bg == 1 || IS_TCP_RECV_BG(so)) { return; } if (tcp_do_autorcvbuf == 1 && (tp->t_flags & TF_SLOWLINK) == 0 && (so->so_flags1 & SOF1_EXTEND_BK_IDLE_WANTED) == 0 && (rcvbuf - sb->sb_cc) < rcvbufinc && rcvbuf < tcp_autorcvbuf_max && (sb->sb_idealsize > 0 && sb->sb_hiwat <= (sb->sb_idealsize + rcvbufinc))) { sbreserve(sb, min((sb->sb_hiwat + rcvbufinc), tcp_autorcvbuf_max)); } } int32_t tcp_sbspace(struct tcpcb *tp) { struct socket *so = tp->t_inpcb->inp_socket; struct sockbuf *sb = &so->so_rcv; u_int32_t rcvbuf; int32_t space; int32_t pending = 0; if (so->so_flags & SOF_MP_SUBFLOW) { /* We still need to grow TCP's buffer to have a BDP-estimate */ tcp_sbrcv_grow_rwin(tp, sb); return mptcp_sbspace(tptomptp(tp)); } tcp_sbrcv_grow_rwin(tp, sb); /* hiwat might have changed */ rcvbuf = sb->sb_hiwat; space = ((int32_t) imin((rcvbuf - sb->sb_cc), (sb->sb_mbmax - sb->sb_mbcnt))); if (space < 0) { space = 0; } #if CONTENT_FILTER /* Compensate for data being processed by content filters */ pending = cfil_sock_data_space(sb); #endif /* CONTENT_FILTER */ if (pending > space) { space = 0; } else { space -= pending; } /* * Avoid increasing window size if the current window * is already very low, we could be in "persist" mode and * we could break some apps (see rdar://5409343) */ if (space < tp->t_maxseg) { return space; } /* Clip window size for slower link */ if (((tp->t_flags & TF_SLOWLINK) != 0) && slowlink_wsize > 0) { return imin(space, slowlink_wsize); } return space; } /* * Checks TCP Segment Offloading capability for a given connection * and interface pair. */ void tcp_set_tso(struct tcpcb *tp, struct ifnet *ifp) { struct inpcb *inp; int isipv6; struct ifnet *tunnel_ifp = NULL; #define IFNET_TSO_MASK (IFNET_TSO_IPV6 | IFNET_TSO_IPV4) tp->t_flags &= ~TF_TSO; /* * Bail if there's a non-TSO-capable filter on the interface. */ if (ifp == NULL || ifp->if_flt_no_tso_count > 0) { return; } inp = tp->t_inpcb; isipv6 = (inp->inp_vflag & INP_IPV6) != 0; #if MPTCP /* * We can't use TSO if this tcpcb belongs to an MPTCP session. */ if (inp->inp_socket->so_flags & SOF_MP_SUBFLOW) { return; } #endif /* * We can't use TSO if the TSO capability of the tunnel interface does * not match the capability of another interface known by TCP */ if (inp->inp_policyresult.results.result == NECP_KERNEL_POLICY_RESULT_IP_TUNNEL) { u_int tunnel_if_index = inp->inp_policyresult.results.result_parameter.tunnel_interface_index; if (tunnel_if_index != 0) { ifnet_head_lock_shared(); tunnel_ifp = ifindex2ifnet[tunnel_if_index]; ifnet_head_done(); } if (tunnel_ifp == NULL) { return; } if ((ifp->if_hwassist & IFNET_TSO_MASK) != (tunnel_ifp->if_hwassist & IFNET_TSO_MASK)) { if (tso_debug > 0) { os_log(OS_LOG_DEFAULT, "%s: %u > %u TSO 0 tunnel_ifp %s hwassist mismatch with ifp %s", __func__, ntohs(tp->t_inpcb->inp_lport), ntohs(tp->t_inpcb->inp_fport), tunnel_ifp->if_xname, ifp->if_xname); } return; } if (inp->inp_last_outifp != NULL && (inp->inp_last_outifp->if_hwassist & IFNET_TSO_MASK) != (tunnel_ifp->if_hwassist & IFNET_TSO_MASK)) { if (tso_debug > 0) { os_log(OS_LOG_DEFAULT, "%s: %u > %u TSO 0 tunnel_ifp %s hwassist mismatch with inp_last_outifp %s", __func__, ntohs(tp->t_inpcb->inp_lport), ntohs(tp->t_inpcb->inp_fport), tunnel_ifp->if_xname, inp->inp_last_outifp->if_xname); } return; } if ((inp->inp_flags & INP_BOUND_IF) && inp->inp_boundifp != NULL && (inp->inp_boundifp->if_hwassist & IFNET_TSO_MASK) != (tunnel_ifp->if_hwassist & IFNET_TSO_MASK)) { if (tso_debug > 0) { os_log(OS_LOG_DEFAULT, "%s: %u > %u TSO 0 tunnel_ifp %s hwassist mismatch with inp_boundifp %s", __func__, ntohs(tp->t_inpcb->inp_lport), ntohs(tp->t_inpcb->inp_fport), tunnel_ifp->if_xname, inp->inp_boundifp->if_xname); } return; } } if (isipv6) { if (ifp->if_hwassist & IFNET_TSO_IPV6) { tp->t_flags |= TF_TSO; if (ifp->if_tso_v6_mtu != 0) { tp->tso_max_segment_size = ifp->if_tso_v6_mtu; } else { tp->tso_max_segment_size = TCP_MAXWIN; } } } else { if (ifp->if_hwassist & IFNET_TSO_IPV4) { tp->t_flags |= TF_TSO; if (ifp->if_tso_v4_mtu != 0) { tp->tso_max_segment_size = ifp->if_tso_v4_mtu; } else { tp->tso_max_segment_size = TCP_MAXWIN; } if (INTF_ADJUST_MTU_FOR_CLAT46(ifp)) { tp->tso_max_segment_size -= CLAT46_HDR_EXPANSION_OVERHD; } } } if (tso_debug > 1) { os_log(OS_LOG_DEFAULT, "%s: %u > %u TSO %d ifp %s", __func__, ntohs(tp->t_inpcb->inp_lport), ntohs(tp->t_inpcb->inp_fport), (tp->t_flags & TF_TSO) != 0, ifp != NULL ? ifp->if_xname : ""); } } #define TIMEVAL_TO_TCPHZ(_tv_) ((uint32_t)((_tv_).tv_sec * TCP_RETRANSHZ + \ (_tv_).tv_usec / TCP_RETRANSHZ_TO_USEC)) /* * Function to calculate the tcp clock. The tcp clock will get updated * at the boundaries of the tcp layer. This is done at 3 places: * 1. Right before processing an input tcp packet * 2. Whenever a connection wants to access the network using tcp_usrreqs * 3. When a tcp timer fires or before tcp slow timeout * */ void calculate_tcp_clock(void) { struct timeval tv = tcp_uptime; struct timeval interval = {.tv_sec = 0, .tv_usec = TCP_RETRANSHZ_TO_USEC}; struct timeval now, hold_now; uint32_t incr = 0; microuptime(&now); /* * Update coarse-grained networking timestamp (in sec.); the idea * is to update the counter returnable via net_uptime() when * we read time. */ net_update_uptime_with_time(&now); timevaladd(&tv, &interval); if (timevalcmp(&now, &tv, >)) { /* time to update the clock */ lck_spin_lock(&tcp_uptime_lock); if (timevalcmp(&tcp_uptime, &now, >=)) { /* clock got updated while waiting for the lock */ lck_spin_unlock(&tcp_uptime_lock); return; } microuptime(&now); hold_now = now; tv = tcp_uptime; timevalsub(&now, &tv); incr = TIMEVAL_TO_TCPHZ(now); /* Account for the previous remainder */ uint32_t remaining_us = (now.tv_usec % TCP_RETRANSHZ_TO_USEC) + tcp_now_remainder_us; if (remaining_us >= TCP_RETRANSHZ_TO_USEC) { incr += (remaining_us / TCP_RETRANSHZ_TO_USEC); } if (incr > 0) { tcp_uptime = hold_now; tcp_now_remainder_us = remaining_us % TCP_RETRANSHZ_TO_USEC; tcp_now += incr; } lck_spin_unlock(&tcp_uptime_lock); } } /* * Compute receive window scaling that we are going to request * for this connection based on sb_hiwat. Try to leave some * room to potentially increase the window size upto a maximum * defined by the constant tcp_autorcvbuf_max. */ void tcp_set_max_rwinscale(struct tcpcb *tp, struct socket *so) { uint32_t maxsockbufsize; tp->request_r_scale = MAX((uint8_t)tcp_win_scale, tp->request_r_scale); maxsockbufsize = ((so->so_rcv.sb_flags & SB_USRSIZE) != 0) ? so->so_rcv.sb_hiwat : tcp_autorcvbuf_max; /* * Window scale should not exceed what is needed * to send the max receive window size; adding 1 to TCP_MAXWIN * ensures that. */ while (tp->request_r_scale < TCP_MAX_WINSHIFT && ((TCP_MAXWIN + 1) << tp->request_r_scale) < maxsockbufsize) { tp->request_r_scale++; } tp->request_r_scale = MIN(tp->request_r_scale, TCP_MAX_WINSHIFT); } int tcp_notsent_lowat_check(struct socket *so) { struct inpcb *inp = sotoinpcb(so); struct tcpcb *tp = NULL; int notsent = 0; if (inp != NULL) { tp = intotcpcb(inp); } if (tp == NULL) { return 0; } notsent = so->so_snd.sb_cc - (tp->snd_nxt - tp->snd_una); /* * When we send a FIN or SYN, not_sent can be negative. * In that case also we need to send a write event to the * process if it is waiting. In the FIN case, it will * get an error from send because cantsendmore will be set. */ if (notsent <= tp->t_notsent_lowat) { return 1; } /* * When Nagle's algorithm is not disabled, it is better * to wakeup the client until there is atleast one * maxseg of data to write. */ if ((tp->t_flags & TF_NODELAY) == 0 && notsent > 0 && notsent < tp->t_maxseg) { return 1; } return 0; } void tcp_rxtseg_insert(struct tcpcb *tp, tcp_seq start, tcp_seq end) { struct tcp_rxt_seg *rxseg = NULL, *prev = NULL, *next = NULL; uint16_t rxcount = 0; if (SLIST_EMPTY(&tp->t_rxt_segments)) { tp->t_dsack_lastuna = tp->snd_una; } /* * First check if there is a segment already existing for this * sequence space. */ SLIST_FOREACH(rxseg, &tp->t_rxt_segments, rx_link) { if (SEQ_GT(rxseg->rx_start, start)) { break; } prev = rxseg; } next = rxseg; /* check if prev seg is for this sequence */ if (prev != NULL && SEQ_LEQ(prev->rx_start, start) && SEQ_GEQ(prev->rx_end, end)) { prev->rx_count++; return; } /* * There are a couple of possibilities at this point. * 1. prev overlaps with the beginning of this sequence * 2. next overlaps with the end of this sequence * 3. there is no overlap. */ if (prev != NULL && SEQ_GT(prev->rx_end, start)) { if (prev->rx_start == start && SEQ_GT(end, prev->rx_end)) { start = prev->rx_end + 1; prev->rx_count++; } else { prev->rx_end = (start - 1); rxcount = prev->rx_count; } } if (next != NULL && SEQ_LT(next->rx_start, end)) { if (SEQ_LEQ(next->rx_end, end)) { end = next->rx_start - 1; next->rx_count++; } else { next->rx_start = end + 1; rxcount = next->rx_count; } } if (!SEQ_LT(start, end)) { return; } if (tcp_rxt_seg_max > 0 && tp->t_rxt_seg_count >= tcp_rxt_seg_max) { rxseg = SLIST_FIRST(&tp->t_rxt_segments); if (prev == rxseg) { prev = NULL; } SLIST_REMOVE(&tp->t_rxt_segments, rxseg, tcp_rxt_seg, rx_link); tcp_rxt_seg_drop++; tp->t_rxt_seg_drop++; TCP_LOG(tp, "removed rxseg list overflow %u:%u ", rxseg->rx_start, rxseg->rx_end); zfree(tcp_rxt_seg_zone, rxseg); tp->t_rxt_seg_count -= 1; } rxseg = zalloc_flags(tcp_rxt_seg_zone, Z_WAITOK | Z_ZERO | Z_NOFAIL); rxseg->rx_start = start; rxseg->rx_end = end; rxseg->rx_count = rxcount + 1; if (prev != NULL) { SLIST_INSERT_AFTER(prev, rxseg, rx_link); } else { SLIST_INSERT_HEAD(&tp->t_rxt_segments, rxseg, rx_link); } tp->t_rxt_seg_count += 1; } struct tcp_rxt_seg * tcp_rxtseg_find(struct tcpcb *tp, tcp_seq start, tcp_seq end) { struct tcp_rxt_seg *rxseg; if (SLIST_EMPTY(&tp->t_rxt_segments)) { return NULL; } SLIST_FOREACH(rxseg, &tp->t_rxt_segments, rx_link) { if (SEQ_LEQ(rxseg->rx_start, start) && SEQ_GEQ(rxseg->rx_end, end)) { return rxseg; } if (SEQ_GT(rxseg->rx_start, start)) { break; } } return NULL; } void tcp_rxtseg_set_spurious(struct tcpcb *tp, tcp_seq start, tcp_seq end) { struct tcp_rxt_seg *rxseg; if (SLIST_EMPTY(&tp->t_rxt_segments)) { return; } SLIST_FOREACH(rxseg, &tp->t_rxt_segments, rx_link) { if (SEQ_GEQ(rxseg->rx_start, start) && SEQ_LEQ(rxseg->rx_end, end)) { /* * If the segment was retransmitted only once, mark it as * spurious. */ if (rxseg->rx_count == 1) { rxseg->rx_flags |= TCP_RXT_SPURIOUS; } } if (SEQ_GEQ(rxseg->rx_start, end)) { break; } } return; } void tcp_rxtseg_clean(struct tcpcb *tp) { struct tcp_rxt_seg *rxseg, *next; SLIST_FOREACH_SAFE(rxseg, &tp->t_rxt_segments, rx_link, next) { SLIST_REMOVE(&tp->t_rxt_segments, rxseg, tcp_rxt_seg, rx_link); zfree(tcp_rxt_seg_zone, rxseg); } tp->t_rxt_seg_count = 0; tp->t_dsack_lastuna = tp->snd_max; } boolean_t tcp_rxtseg_detect_bad_rexmt(struct tcpcb *tp, tcp_seq th_ack) { boolean_t bad_rexmt; struct tcp_rxt_seg *rxseg; if (SLIST_EMPTY(&tp->t_rxt_segments)) { return FALSE; } /* * If all of the segments in this window are not cumulatively * acknowledged, then there can still be undetected packet loss. * Do not restore congestion window in that case. */ if (SEQ_LT(th_ack, tp->snd_recover)) { return FALSE; } bad_rexmt = TRUE; SLIST_FOREACH(rxseg, &tp->t_rxt_segments, rx_link) { if (!(rxseg->rx_flags & TCP_RXT_SPURIOUS)) { bad_rexmt = FALSE; break; } } return bad_rexmt; } u_int32_t tcp_rxtseg_total_size(struct tcpcb *tp) { struct tcp_rxt_seg *rxseg; u_int32_t total_size = 0; SLIST_FOREACH(rxseg, &tp->t_rxt_segments, rx_link) { total_size += (rxseg->rx_end - rxseg->rx_start) + 1; } return total_size; } void tcp_get_connectivity_status(struct tcpcb *tp, struct tcp_conn_status *connstatus) { if (tp == NULL || connstatus == NULL) { return; } bzero(connstatus, sizeof(*connstatus)); if (tp->t_rxtshift >= TCP_CONNECTIVITY_PROBES_MAX) { if (TCPS_HAVEESTABLISHED(tp->t_state)) { connstatus->write_probe_failed = 1; } else { connstatus->conn_probe_failed = 1; } } if (tp->t_rtimo_probes >= TCP_CONNECTIVITY_PROBES_MAX) { connstatus->read_probe_failed = 1; } if (tp->t_inpcb != NULL && tp->t_inpcb->inp_last_outifp != NULL && (tp->t_inpcb->inp_last_outifp->if_eflags & IFEF_PROBE_CONNECTIVITY)) { connstatus->probe_activated = 1; } } boolean_t tfo_enabled(const struct tcpcb *tp) { return (tp->t_flagsext & TF_FASTOPEN)? TRUE : FALSE; } void tcp_disable_tfo(struct tcpcb *tp) { tp->t_flagsext &= ~TF_FASTOPEN; } static struct mbuf * tcp_make_keepalive_frame(struct tcpcb *tp, struct ifnet *ifp, boolean_t is_probe) { struct inpcb *inp = tp->t_inpcb; struct tcphdr *th; u_int8_t *data; int win = 0; struct mbuf *m; /* * The code assumes the IP + TCP headers fit in an mbuf packet header */ _CASSERT(sizeof(struct ip) + sizeof(struct tcphdr) <= _MHLEN); _CASSERT(sizeof(struct ip6_hdr) + sizeof(struct tcphdr) <= _MHLEN); MGETHDR(m, M_WAIT, MT_HEADER); if (m == NULL) { return NULL; } m->m_pkthdr.pkt_proto = IPPROTO_TCP; data = mbuf_datastart(m); if (inp->inp_vflag & INP_IPV4) { bzero(data, sizeof(struct ip) + sizeof(struct tcphdr)); th = (struct tcphdr *)(void *) (data + sizeof(struct ip)); m->m_len = sizeof(struct ip) + sizeof(struct tcphdr); m->m_pkthdr.len = m->m_len; } else { VERIFY(inp->inp_vflag & INP_IPV6); bzero(data, sizeof(struct ip6_hdr) + sizeof(struct tcphdr)); th = (struct tcphdr *)(void *)(data + sizeof(struct ip6_hdr)); m->m_len = sizeof(struct ip6_hdr) + sizeof(struct tcphdr); m->m_pkthdr.len = m->m_len; } tcp_fillheaders(m, tp, data, th); if (inp->inp_vflag & INP_IPV4) { struct ip *ip; ip = (__typeof__(ip))(void *)data; ip->ip_id = rfc6864 ? 0 : ip_randomid((uint64_t)m); ip->ip_off = htons(IP_DF); ip->ip_len = htons(sizeof(struct ip) + sizeof(struct tcphdr)); ip->ip_ttl = inp->inp_ip_ttl; ip->ip_tos |= (inp->inp_ip_tos & ~IPTOS_ECN_MASK); ip->ip_sum = in_cksum_hdr(ip); } else { struct ip6_hdr *ip6; ip6 = (__typeof__(ip6))(void *)data; ip6->ip6_plen = htons(sizeof(struct tcphdr)); ip6->ip6_hlim = in6_selecthlim(inp, ifp); ip6->ip6_flow = ip6->ip6_flow & ~IPV6_FLOW_ECN_MASK; if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) { ip6->ip6_src.s6_addr16[1] = 0; } if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) { ip6->ip6_dst.s6_addr16[1] = 0; } } th->th_flags = TH_ACK; win = tcp_sbspace(tp); if (win > ((int32_t)TCP_MAXWIN << tp->rcv_scale)) { win = (int32_t)TCP_MAXWIN << tp->rcv_scale; } th->th_win = htons((u_short) (win >> tp->rcv_scale)); if (is_probe) { th->th_seq = htonl(tp->snd_una - 1); } else { th->th_seq = htonl(tp->snd_una); } th->th_ack = htonl(tp->rcv_nxt); /* Force recompute TCP checksum to be the final value */ th->th_sum = 0; if (inp->inp_vflag & INP_IPV4) { th->th_sum = inet_cksum(m, IPPROTO_TCP, sizeof(struct ip), sizeof(struct tcphdr)); } else { th->th_sum = inet6_cksum(m, IPPROTO_TCP, sizeof(struct ip6_hdr), sizeof(struct tcphdr)); } return m; } void tcp_fill_keepalive_offload_frames(ifnet_t ifp, struct ifnet_keepalive_offload_frame *frames_array, u_int32_t frames_array_count, size_t frame_data_offset, u_int32_t *used_frames_count) { struct inpcb *inp; inp_gen_t gencnt; u_int32_t frame_index = *used_frames_count; if (ifp == NULL || frames_array == NULL || frames_array_count == 0 || frame_index >= frames_array_count || frame_data_offset >= IFNET_KEEPALIVE_OFFLOAD_FRAME_DATA_SIZE) { return; } /* * This function is called outside the regular TCP processing * so we need to update the TCP clock. */ calculate_tcp_clock(); lck_rw_lock_shared(&tcbinfo.ipi_lock); gencnt = tcbinfo.ipi_gencnt; LIST_FOREACH(inp, tcbinfo.ipi_listhead, inp_list) { struct socket *so; struct ifnet_keepalive_offload_frame *frame; struct mbuf *m = NULL; struct tcpcb *tp = intotcpcb(inp); if (frame_index >= frames_array_count) { break; } if (inp->inp_gencnt > gencnt || inp->inp_state == INPCB_STATE_DEAD) { continue; } if ((so = inp->inp_socket) == NULL || (so->so_state & SS_DEFUNCT)) { continue; } /* * check for keepalive offload flag without socket * lock to avoid a deadlock */ if (!(inp->inp_flags2 & INP2_KEEPALIVE_OFFLOAD)) { continue; } if (!(inp->inp_vflag & (INP_IPV4 | INP_IPV6))) { continue; } if (inp->inp_ppcb == NULL || in_pcb_checkstate(inp, WNT_ACQUIRE, 0) == WNT_STOPUSING) { continue; } socket_lock(so, 1); /* Release the want count */ if (inp->inp_ppcb == NULL || (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING)) { socket_unlock(so, 1); continue; } if ((inp->inp_vflag & INP_IPV4) && (inp->inp_laddr.s_addr == INADDR_ANY || inp->inp_faddr.s_addr == INADDR_ANY)) { socket_unlock(so, 1); continue; } if ((inp->inp_vflag & INP_IPV6) && (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) || IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr))) { socket_unlock(so, 1); continue; } if (inp->inp_lport == 0 || inp->inp_fport == 0) { socket_unlock(so, 1); continue; } if (inp->inp_last_outifp == NULL || inp->inp_last_outifp->if_index != ifp->if_index) { socket_unlock(so, 1); continue; } if ((inp->inp_vflag & INP_IPV4) && frame_data_offset + sizeof(struct ip) + sizeof(struct tcphdr) > IFNET_KEEPALIVE_OFFLOAD_FRAME_DATA_SIZE) { socket_unlock(so, 1); continue; } else if (!(inp->inp_vflag & INP_IPV4) && frame_data_offset + sizeof(struct ip6_hdr) + sizeof(struct tcphdr) > IFNET_KEEPALIVE_OFFLOAD_FRAME_DATA_SIZE) { socket_unlock(so, 1); continue; } /* * There is no point in waking up the device for connections * that are not established. Long lived connection are meant * for processes that will sent and receive data */ if (tp->t_state != TCPS_ESTABLISHED) { socket_unlock(so, 1); continue; } /* * This inp has all the information that is needed to * generate an offload frame. */ frame = &frames_array[frame_index]; frame->type = IFNET_KEEPALIVE_OFFLOAD_FRAME_TCP; frame->ether_type = (inp->inp_vflag & INP_IPV4) ? IFNET_KEEPALIVE_OFFLOAD_FRAME_ETHERTYPE_IPV4 : IFNET_KEEPALIVE_OFFLOAD_FRAME_ETHERTYPE_IPV6; frame->interval = (uint16_t)(tp->t_keepidle > 0 ? tp->t_keepidle : tcp_keepidle); frame->keep_cnt = (uint8_t)TCP_CONN_KEEPCNT(tp); frame->keep_retry = (uint16_t)TCP_CONN_KEEPINTVL(tp); if (so->so_options & SO_NOWAKEFROMSLEEP) { frame->flags |= IFNET_KEEPALIVE_OFFLOAD_FLAG_NOWAKEFROMSLEEP; } frame->local_port = ntohs(inp->inp_lport); frame->remote_port = ntohs(inp->inp_fport); frame->local_seq = tp->snd_nxt; frame->remote_seq = tp->rcv_nxt; if (inp->inp_vflag & INP_IPV4) { ASSERT(frame_data_offset + sizeof(struct ip) + sizeof(struct tcphdr) <= UINT8_MAX); frame->length = (uint8_t)(frame_data_offset + sizeof(struct ip) + sizeof(struct tcphdr)); frame->reply_length = frame->length; frame->addr_length = sizeof(struct in_addr); bcopy(&inp->inp_laddr, frame->local_addr, sizeof(struct in_addr)); bcopy(&inp->inp_faddr, frame->remote_addr, sizeof(struct in_addr)); } else { struct in6_addr *ip6; ASSERT(frame_data_offset + sizeof(struct ip6_hdr) + sizeof(struct tcphdr) <= UINT8_MAX); frame->length = (uint8_t)(frame_data_offset + sizeof(struct ip6_hdr) + sizeof(struct tcphdr)); frame->reply_length = frame->length; frame->addr_length = sizeof(struct in6_addr); ip6 = (struct in6_addr *)(void *)frame->local_addr; bcopy(&inp->in6p_laddr, ip6, sizeof(struct in6_addr)); if (IN6_IS_SCOPE_EMBED(ip6)) { ip6->s6_addr16[1] = 0; } ip6 = (struct in6_addr *)(void *)frame->remote_addr; bcopy(&inp->in6p_faddr, ip6, sizeof(struct in6_addr)); if (IN6_IS_SCOPE_EMBED(ip6)) { ip6->s6_addr16[1] = 0; } } /* * First the probe */ m = tcp_make_keepalive_frame(tp, ifp, TRUE); if (m == NULL) { socket_unlock(so, 1); continue; } bcopy(m_mtod_current(m), frame->data + frame_data_offset, m->m_len); m_freem(m); /* * Now the response packet to incoming probes */ m = tcp_make_keepalive_frame(tp, ifp, FALSE); if (m == NULL) { socket_unlock(so, 1); continue; } bcopy(m_mtod_current(m), frame->reply_data + frame_data_offset, m->m_len); m_freem(m); frame_index++; socket_unlock(so, 1); } lck_rw_done(&tcbinfo.ipi_lock); *used_frames_count = frame_index; } static bool inp_matches_kao_frame(ifnet_t ifp, struct ifnet_keepalive_offload_frame *frame, struct inpcb *inp) { if (inp->inp_ppcb == NULL) { return false; } /* Release the want count */ if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) { return false; } if (inp->inp_last_outifp == NULL || inp->inp_last_outifp->if_index != ifp->if_index) { return false; } if (frame->local_port != ntohs(inp->inp_lport) || frame->remote_port != ntohs(inp->inp_fport)) { return false; } if (inp->inp_vflag & INP_IPV4) { if (memcmp(&inp->inp_laddr, frame->local_addr, sizeof(struct in_addr)) != 0 || memcmp(&inp->inp_faddr, frame->remote_addr, sizeof(struct in_addr)) != 0) { return false; } } else if (inp->inp_vflag & INP_IPV6) { if (memcmp(&inp->inp_laddr, frame->local_addr, sizeof(struct in6_addr)) != 0 || memcmp(&inp->inp_faddr, frame->remote_addr, sizeof(struct in6_addr)) != 0) { return false; } } else { return false; } return true; } int tcp_notify_kao_timeout(ifnet_t ifp, struct ifnet_keepalive_offload_frame *frame) { struct inpcb *inp = NULL; struct socket *so = NULL; bool found = false; /* * Unlock the list before posting event on the matching socket */ lck_rw_lock_shared(&tcbinfo.ipi_lock); LIST_FOREACH(inp, tcbinfo.ipi_listhead, inp_list) { if ((so = inp->inp_socket) == NULL || (so->so_state & SS_DEFUNCT)) { continue; } if (!(inp->inp_flags2 & INP2_KEEPALIVE_OFFLOAD)) { continue; } if (!(inp->inp_vflag & (INP_IPV4 | INP_IPV6))) { continue; } if (inp->inp_ppcb == NULL || in_pcb_checkstate(inp, WNT_ACQUIRE, 0) == WNT_STOPUSING) { continue; } socket_lock(so, 1); if (inp_matches_kao_frame(ifp, frame, inp)) { /* * Keep the matching socket locked */ found = true; break; } socket_unlock(so, 1); } lck_rw_done(&tcbinfo.ipi_lock); if (found) { ASSERT(inp != NULL); ASSERT(so != NULL); ASSERT(so == inp->inp_socket); /* * Drop the TCP connection like tcptimers() does */ struct tcpcb *tp = inp->inp_ppcb; tcpstat.tcps_keepdrops++; soevent(so, (SO_FILT_HINT_LOCKED | SO_FILT_HINT_TIMEOUT)); tp = tcp_drop(tp, ETIMEDOUT); tcpstat.tcps_ka_offload_drops++; os_log_info(OS_LOG_DEFAULT, "%s: dropped lport %u fport %u\n", __func__, frame->local_port, frame->remote_port); socket_unlock(so, 1); } return 0; } errno_t tcp_notify_ack_id_valid(struct tcpcb *tp, struct socket *so, u_int32_t notify_id) { struct tcp_notify_ack_marker *elm; if (so->so_snd.sb_cc == 0) { return ENOBUFS; } SLIST_FOREACH(elm, &tp->t_notify_ack, notify_next) { /* Duplicate id is not allowed */ if (elm->notify_id == notify_id) { return EINVAL; } /* Duplicate position is not allowed */ if (elm->notify_snd_una == tp->snd_una + so->so_snd.sb_cc) { return EINVAL; } } return 0; } errno_t tcp_add_notify_ack_marker(struct tcpcb *tp, u_int32_t notify_id) { struct tcp_notify_ack_marker *nm, *elm = NULL; struct socket *so = tp->t_inpcb->inp_socket; nm = kalloc_type(struct tcp_notify_ack_marker, M_WAIT | Z_ZERO); if (nm == NULL) { return ENOMEM; } nm->notify_id = notify_id; nm->notify_snd_una = tp->snd_una + so->so_snd.sb_cc; SLIST_FOREACH(elm, &tp->t_notify_ack, notify_next) { if (SEQ_GT(nm->notify_snd_una, elm->notify_snd_una)) { break; } } if (elm == NULL) { VERIFY(SLIST_EMPTY(&tp->t_notify_ack)); SLIST_INSERT_HEAD(&tp->t_notify_ack, nm, notify_next); } else { SLIST_INSERT_AFTER(elm, nm, notify_next); } tp->t_notify_ack_count++; return 0; } void tcp_notify_ack_free(struct tcpcb *tp) { struct tcp_notify_ack_marker *elm, *next; if (SLIST_EMPTY(&tp->t_notify_ack)) { return; } SLIST_FOREACH_SAFE(elm, &tp->t_notify_ack, notify_next, next) { SLIST_REMOVE(&tp->t_notify_ack, elm, tcp_notify_ack_marker, notify_next); kfree_type(struct tcp_notify_ack_marker, elm); } SLIST_INIT(&tp->t_notify_ack); tp->t_notify_ack_count = 0; } inline void tcp_notify_acknowledgement(struct tcpcb *tp, struct socket *so) { struct tcp_notify_ack_marker *elm; elm = SLIST_FIRST(&tp->t_notify_ack); if (SEQ_GEQ(tp->snd_una, elm->notify_snd_una)) { soevent(so, SO_FILT_HINT_LOCKED | SO_FILT_HINT_NOTIFY_ACK); } } void tcp_get_notify_ack_count(struct tcpcb *tp, struct tcp_notify_ack_complete *retid) { struct tcp_notify_ack_marker *elm; uint32_t complete = 0; SLIST_FOREACH(elm, &tp->t_notify_ack, notify_next) { if (SEQ_GEQ(tp->snd_una, elm->notify_snd_una)) { ASSERT(complete < UINT32_MAX); complete++; } else { break; } } retid->notify_pending = tp->t_notify_ack_count - complete; retid->notify_complete_count = min(TCP_MAX_NOTIFY_ACK, complete); } void tcp_get_notify_ack_ids(struct tcpcb *tp, struct tcp_notify_ack_complete *retid) { size_t i = 0; struct tcp_notify_ack_marker *elm, *next; SLIST_FOREACH_SAFE(elm, &tp->t_notify_ack, notify_next, next) { if (i >= retid->notify_complete_count) { break; } if (SEQ_GEQ(tp->snd_una, elm->notify_snd_una)) { retid->notify_complete_id[i++] = elm->notify_id; SLIST_REMOVE(&tp->t_notify_ack, elm, tcp_notify_ack_marker, notify_next); kfree_type(struct tcp_notify_ack_marker, elm); tp->t_notify_ack_count--; } else { break; } } } bool tcp_notify_ack_active(struct socket *so) { if ((SOCK_DOM(so) == PF_INET || SOCK_DOM(so) == PF_INET6) && SOCK_TYPE(so) == SOCK_STREAM) { struct tcpcb *tp = intotcpcb(sotoinpcb(so)); if (!SLIST_EMPTY(&tp->t_notify_ack)) { struct tcp_notify_ack_marker *elm; elm = SLIST_FIRST(&tp->t_notify_ack); if (SEQ_GEQ(tp->snd_una, elm->notify_snd_una)) { return true; } } } return false; } inline int32_t inp_get_sndbytes_allunsent(struct socket *so, u_int32_t th_ack) { struct inpcb *inp = sotoinpcb(so); struct tcpcb *tp = intotcpcb(inp); if ((so->so_snd.sb_flags & SB_SNDBYTE_CNT) && so->so_snd.sb_cc > 0) { int32_t unsent, sent; sent = tp->snd_max - th_ack; if (tp->t_flags & TF_SENTFIN) { sent--; } unsent = so->so_snd.sb_cc - sent; return unsent; } return 0; } uint8_t tcp_get_ace(struct tcphdr *th) { uint8_t ace = 0; if (th->th_flags & TH_ECE) { ace += 1; } if (th->th_flags & TH_CWR) { ace += 2; } if (th->th_x2 & (TH_AE >> 8)) { ace += 4; } return ace; } #define IFP_PER_FLOW_STAT(_ipv4_, _stat_) { \ if (_ipv4_) { \ ifp->if_ipv4_stat->_stat_++; \ } else { \ ifp->if_ipv6_stat->_stat_++; \ } \ } #define FLOW_ECN_ENABLED(_flags_) \ ((_flags_ & (TE_ECN_ON)) == (TE_ECN_ON)) void tcp_update_stats_per_flow(struct ifnet_stats_per_flow *ifs, struct ifnet *ifp) { if (ifp == NULL || !IF_FULLY_ATTACHED(ifp)) { return; } ifnet_lock_shared(ifp); if (ifs->ecn_flags & TE_SETUPSENT) { if (ifs->ecn_flags & TE_CLIENT_SETUP) { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_client_setup); if (FLOW_ECN_ENABLED(ifs->ecn_flags)) { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_client_success); } else if (ifs->ecn_flags & TE_LOST_SYN) { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_syn_lost); } else { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_peer_nosupport); } } else { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_server_setup); if (FLOW_ECN_ENABLED(ifs->ecn_flags)) { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_server_success); } else if (ifs->ecn_flags & TE_LOST_SYN) { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_synack_lost); } else { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_peer_nosupport); } } } else { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_off_conn); } if (FLOW_ECN_ENABLED(ifs->ecn_flags)) { if (ifs->ecn_flags & TE_RECV_ECN_CE) { tcpstat.tcps_ecn_conn_recv_ce++; IFP_PER_FLOW_STAT(ifs->ipv4, ecn_conn_recv_ce); } if (ifs->ecn_flags & TE_RECV_ECN_ECE) { tcpstat.tcps_ecn_conn_recv_ece++; IFP_PER_FLOW_STAT(ifs->ipv4, ecn_conn_recv_ece); } if (ifs->ecn_flags & (TE_RECV_ECN_CE | TE_RECV_ECN_ECE)) { if (ifs->txretransmitbytes > 0 || ifs->rxoutoforderbytes > 0) { tcpstat.tcps_ecn_conn_pl_ce++; IFP_PER_FLOW_STAT(ifs->ipv4, ecn_conn_plce); } else { tcpstat.tcps_ecn_conn_nopl_ce++; IFP_PER_FLOW_STAT(ifs->ipv4, ecn_conn_noplce); } } else { if (ifs->txretransmitbytes > 0 || ifs->rxoutoforderbytes > 0) { tcpstat.tcps_ecn_conn_plnoce++; IFP_PER_FLOW_STAT(ifs->ipv4, ecn_conn_plnoce); } } } /* Other stats are interesting for non-local connections only */ if (ifs->local) { ifnet_lock_done(ifp); return; } if (ifs->ipv4) { ifp->if_ipv4_stat->timestamp = net_uptime(); if (FLOW_ECN_ENABLED(ifs->ecn_flags)) { tcp_flow_ecn_perf_stats(ifs, &ifp->if_ipv4_stat->ecn_on); } else { tcp_flow_ecn_perf_stats(ifs, &ifp->if_ipv4_stat->ecn_off); } } else { ifp->if_ipv6_stat->timestamp = net_uptime(); if (FLOW_ECN_ENABLED(ifs->ecn_flags)) { tcp_flow_ecn_perf_stats(ifs, &ifp->if_ipv6_stat->ecn_on); } else { tcp_flow_ecn_perf_stats(ifs, &ifp->if_ipv6_stat->ecn_off); } } if (ifs->rxmit_drop) { if (FLOW_ECN_ENABLED(ifs->ecn_flags)) { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_on.rxmit_drop); } else { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_off.rxmit_drop); } } if (ifs->ecn_fallback_synloss) { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_fallback_synloss); } if (ifs->ecn_fallback_droprst) { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_fallback_droprst); } if (ifs->ecn_fallback_droprxmt) { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_fallback_droprxmt); } if (ifs->ecn_fallback_ce) { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_fallback_ce); } if (ifs->ecn_fallback_reorder) { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_fallback_reorder); } if (ifs->ecn_recv_ce > 0) { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_recv_ce); } if (ifs->ecn_recv_ece > 0) { IFP_PER_FLOW_STAT(ifs->ipv4, ecn_recv_ece); } tcp_flow_lim_stats(ifs, &ifp->if_lim_stat); ifnet_lock_done(ifp); } #if SKYWALK #include #include void tcp_add_fsw_flow(struct tcpcb *tp, struct ifnet *ifp) { struct inpcb *inp = tp->t_inpcb; struct socket *so = inp->inp_socket; uuid_t fsw_uuid; struct nx_flow_req nfr; int err; if (!NX_FSW_TCP_RX_AGG_ENABLED()) { return; } if (ifp == NULL || kern_nexus_get_flowswitch_instance(ifp, fsw_uuid)) { TCP_LOG_FSW_FLOW(tp, "skip ifp no fsw"); return; } memset(&nfr, 0, sizeof(nfr)); if (inp->inp_vflag & INP_IPV4) { ASSERT(!(inp->inp_laddr.s_addr == INADDR_ANY || inp->inp_faddr.s_addr == INADDR_ANY || IN_MULTICAST(ntohl(inp->inp_laddr.s_addr)) || IN_MULTICAST(ntohl(inp->inp_faddr.s_addr)))); nfr.nfr_saddr.sin.sin_len = sizeof(struct sockaddr_in); nfr.nfr_saddr.sin.sin_family = AF_INET; nfr.nfr_saddr.sin.sin_port = inp->inp_lport; memcpy(&nfr.nfr_saddr.sin.sin_addr, &inp->inp_laddr, sizeof(struct in_addr)); nfr.nfr_daddr.sin.sin_len = sizeof(struct sockaddr_in); nfr.nfr_daddr.sin.sin_family = AF_INET; nfr.nfr_daddr.sin.sin_port = inp->inp_fport; memcpy(&nfr.nfr_daddr.sin.sin_addr, &inp->inp_faddr, sizeof(struct in_addr)); } else { ASSERT(!(IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) || IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) || IN6_IS_ADDR_MULTICAST(&inp->in6p_laddr) || IN6_IS_ADDR_MULTICAST(&inp->in6p_faddr))); nfr.nfr_saddr.sin6.sin6_len = sizeof(struct sockaddr_in6); nfr.nfr_saddr.sin6.sin6_family = AF_INET6; nfr.nfr_saddr.sin6.sin6_port = inp->inp_lport; memcpy(&nfr.nfr_saddr.sin6.sin6_addr, &inp->in6p_laddr, sizeof(struct in6_addr)); nfr.nfr_daddr.sin6.sin6_len = sizeof(struct sockaddr_in6); nfr.nfr_daddr.sin.sin_family = AF_INET6; nfr.nfr_daddr.sin6.sin6_port = inp->inp_fport; memcpy(&nfr.nfr_daddr.sin6.sin6_addr, &inp->in6p_faddr, sizeof(struct in6_addr)); /* clear embedded scope ID */ if (IN6_IS_SCOPE_EMBED(&nfr.nfr_saddr.sin6.sin6_addr)) { nfr.nfr_saddr.sin6.sin6_addr.s6_addr16[1] = 0; } if (IN6_IS_SCOPE_EMBED(&nfr.nfr_daddr.sin6.sin6_addr)) { nfr.nfr_daddr.sin6.sin6_addr.s6_addr16[1] = 0; } } nfr.nfr_nx_port = 1; nfr.nfr_ip_protocol = IPPROTO_TCP; nfr.nfr_transport_protocol = IPPROTO_TCP; nfr.nfr_flags = NXFLOWREQF_ASIS; nfr.nfr_epid = (so != NULL ? so->last_pid : 0); if (NETNS_TOKEN_VALID(&inp->inp_netns_token)) { nfr.nfr_port_reservation = inp->inp_netns_token; nfr.nfr_flags |= NXFLOWREQF_EXT_PORT_RSV; } ASSERT(inp->inp_flowhash != 0); nfr.nfr_inp_flowhash = inp->inp_flowhash; uuid_generate_random(nfr.nfr_flow_uuid); err = kern_nexus_flow_add(kern_nexus_shared_controller(), fsw_uuid, &nfr, sizeof(nfr)); if (err == 0) { uuid_copy(tp->t_fsw_uuid, fsw_uuid); uuid_copy(tp->t_flow_uuid, nfr.nfr_flow_uuid); } TCP_LOG_FSW_FLOW(tp, "add err %d\n", err); } void tcp_del_fsw_flow(struct tcpcb *tp) { if (uuid_is_null(tp->t_fsw_uuid) || uuid_is_null(tp->t_flow_uuid)) { return; } struct nx_flow_req nfr; uuid_copy(nfr.nfr_flow_uuid, tp->t_flow_uuid); /* It's possible for this call to fail if the nexus has detached */ int err = kern_nexus_flow_del(kern_nexus_shared_controller(), tp->t_fsw_uuid, &nfr, sizeof(nfr)); VERIFY(err == 0 || err == ENOENT || err == ENXIO); uuid_clear(tp->t_fsw_uuid); uuid_clear(tp->t_flow_uuid); TCP_LOG_FSW_FLOW(tp, "del err %d\n", err); } #endif /* SKYWALK */