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https://passt.top/passt
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tcp: Introduce scatter-gather IO path from socket to tap
...similarly to what was done for UDP. Quick performance test with 32KiB buffers, host to VM: $ iperf3 -c 192.0.2.2 -N [ ID] Interval Transfer Bitrate Retr [ 5] 0.00-10.00 sec 8.47 GBytes 7.27 Gbits/sec 0 sender [ 5] 0.00-10.00 sec 8.45 GBytes 7.26 Gbits/sec receiver $ iperf3 -c 2a01:598:88ba:a056:271f:473a:c0d9:abc1 [ ID] Interval Transfer Bitrate Retr [ 5] 0.00-10.00 sec 8.43 GBytes 7.24 Gbits/sec 0 sender [ 5] 0.00-10.00 sec 8.41 GBytes 7.22 Gbits/sec receiver Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
This commit is contained in:
Stefano Brivio
parent
85a820a66f
commit
39ad062100
1
passt.c
1
passt.c
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@ -441,6 +441,7 @@ static void timer_handler(struct ctx *c, struct timespec *now)
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void proto_update_l2_buf(unsigned char *eth_d, unsigned char *eth_s,
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uint32_t *ip_da)
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{
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tcp_update_l2_buf(eth_d, eth_s, ip_da);
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udp_update_l2_buf(eth_d, eth_s, ip_da);
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}
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558
tcp.c
558
tcp.c
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@ -343,14 +343,18 @@
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#include <linux/tcp.h>
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#include <time.h>
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#include "checksum.h"
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#include "util.h"
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#include "passt.h"
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#include "tap.h"
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#include "siphash.h"
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#include "pcap.h"
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#define MAX_TAP_CONNS (128 * 1024)
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#define MAX_SPLICE_CONNS (128 * 1024)
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#define TCP_TAP_FRAMES 64
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#define PIPE_SIZE (1024 * 1024)
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#define TCP_HASH_TABLE_LOAD 70 /* % */
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@ -503,8 +507,101 @@ struct tcp_splice_conn {
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int v6;
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};
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/* Socket receive buffer */
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static char sock_buf[MAX_WINDOW];
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/* Static buffers */
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/**
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* tcp4_l2_buf_t - Pre-cooked IPv4 packet buffers for tap connections
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* @psum: Partial IP header checksum (excluding tot_len and saddr)
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* @psum: Partial TCP header checksum (excluding length and saddr)
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* @vnet_len: 4-byte qemu vnet buffer length descriptor, only for passt mode
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* @eh: Pre-filled Ethernet header
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* @iph: Pre-filled IP header (except for tot_len and saddr)
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* @uh: Headroom for TCP header
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* @data: Storage for TCP payload
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*/
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__extension__ static struct tcp4_l2_buf_t {
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uint32_t psum; /* 0 */
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uint32_t tsum; /* 4 */
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#ifdef __AVX2__
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uint8_t pad[18]; /* 8, align th to 32 bytes */
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#endif
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uint32_t vnet_len; /* 26 */
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struct ethhdr eh; /* 30 */
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struct iphdr iph; /* 44 */
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struct tcphdr th; /* 64 */
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uint8_t data[USHRT_MAX - sizeof(struct tcphdr)];
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#ifdef __AVX2__
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} __attribute__ ((packed, aligned(32)))
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#else
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} __attribute__ ((packed, aligned(__alignof__(unsigned int))))
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#endif
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tcp4_l2_buf[TCP_TAP_FRAMES] = {
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[ 0 ... TCP_TAP_FRAMES - 1 ] = {
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0, 0,
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#ifdef __AVX2__
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{ 0 },
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#endif
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0, L2_BUF_ETH_IP4_INIT, L2_BUF_IP4_INIT(IPPROTO_TCP),
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{ .doff = sizeof(struct tcphdr) / 4, .ack = 1 }, { 0 },
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},
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};
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static int tcp4_l2_buf_mss;
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static int tcp4_l2_buf_mss_nr_set;
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static int tcp4_l2_buf_mss_tap;
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static int tcp4_l2_buf_mss_tap_nr_set;
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/**
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* tcp6_l2_buf_t - Pre-cooked IPv6 packet buffers for tap connections
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* @vnet_len: 4-byte qemu vnet buffer length descriptor, only for passt mode
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* @eh: Pre-filled Ethernet header
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* @ip6h: Pre-filled IP header (except for payload_len and addresses)
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* @th: Headroom for TCP header
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* @data: Storage for TCP payload
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*/
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__extension__ struct tcp6_l2_buf_t {
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#ifdef __AVX2__
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uint8_t pad[14]; /* 0 align ip6h to 32 bytes */
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#else
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uint8_t pad[2]; /* align ip6h to 4 bytes 0 */
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#endif
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uint32_t vnet_len; /* 14 2 */
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struct ethhdr eh; /* 18 6 */
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struct ipv6hdr ip6h; /* 32 20 */
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struct tcphdr th; /* 72 60 */
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uint8_t data[USHRT_MAX -
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(sizeof(struct ipv6hdr) + sizeof(struct tcphdr))];
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#ifdef __AVX2__
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} __attribute__ ((packed, aligned(32)))
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#else
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} __attribute__ ((packed, aligned(__alignof__(unsigned int))))
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#endif
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tcp6_l2_buf[TCP_TAP_FRAMES] = {
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[ 0 ... TCP_TAP_FRAMES - 1 ] = {
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{ 0 },
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0, L2_BUF_ETH_IP6_INIT, L2_BUF_IP6_INIT(IPPROTO_TCP),
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{ .doff = sizeof(struct tcphdr) / 4, .ack = 1 }, { 0 },
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},
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};
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static int tcp6_l2_buf_mss;
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static int tcp6_l2_buf_mss_nr_set;
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static int tcp6_l2_buf_mss_tap;
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static int tcp6_l2_buf_mss_tap_nr_set;
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/* recvmmsg()/sendmmsg() data for tap */
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static struct iovec tcp4_l2_iov_sock [TCP_TAP_FRAMES + 1];
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static struct iovec tcp6_l2_iov_sock [TCP_TAP_FRAMES + 1];
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static char tcp_buf_discard [MAX_WINDOW];
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static struct iovec tcp4_l2_iov_tap [TCP_TAP_FRAMES];
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static struct iovec tcp6_l2_iov_tap [TCP_TAP_FRAMES];
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static struct msghdr tcp4_l2_mh_sock;
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static struct msghdr tcp6_l2_mh_sock;
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static struct mmsghdr tcp_l2_mh_tap [TCP_TAP_FRAMES];
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/* Bitmap, activity monitoring needed for connection via tap */
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static uint8_t tcp_act[MAX_TAP_CONNS / 8] = { 0 };
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@ -540,6 +637,148 @@ static void tcp_splice_state(struct tcp_splice_conn *conn, enum tcp_state state)
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conn->state = state;
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}
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/**
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* tcp_update_check_ip4() - Update IPv4 with variable parts from stored one
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* @buf: L2 packet buffer with final IPv4 header
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*/
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static void tcp_update_check_ip4(struct tcp4_l2_buf_t *buf)
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{
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uint32_t sum = buf->psum;
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sum += buf->iph.tot_len;
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sum += (buf->iph.saddr >> 16) & 0xffff;
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sum += buf->iph.saddr & 0xffff;
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buf->iph.check = (uint16_t)~csum_fold(sum);
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}
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/**
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* tcp_update_check_tcp4() - Update TCP checksum from stored one
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* @buf: L2 packet buffer with final IPv4 header
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*/
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static void tcp_update_check_tcp4(struct tcp4_l2_buf_t *buf)
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{
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uint16_t tlen = ntohs(buf->iph.tot_len) - 20;
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uint32_t sum = buf->tsum;
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sum += (buf->iph.saddr >> 16) & 0xffff;
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sum += buf->iph.saddr & 0xffff;
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sum += htons(ntohs(buf->iph.tot_len) - 20);
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buf->th.check = 0;
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buf->th.check = csum(&buf->th, tlen, sum);
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}
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/**
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* tcp_update_check_tcp6() - Calculate TCP checksum for IPv6
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* @buf: L2 packet buffer with final IPv6 header
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*/
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static void tcp_update_check_tcp6(struct tcp6_l2_buf_t *buf)
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{
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int len = ntohs(buf->ip6h.payload_len) + sizeof(struct ipv6hdr);
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buf->ip6h.hop_limit = IPPROTO_TCP;
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buf->ip6h.version = 0;
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buf->ip6h.nexthdr = 0;
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buf->th.check = 0;
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buf->th.check = csum(&buf->ip6h, len, 0);
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buf->ip6h.hop_limit = 255;
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buf->ip6h.version = 6;
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buf->ip6h.nexthdr = IPPROTO_TCP;
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}
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/**
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* tcp_update_l2_buf() - Update L2 buffers with Ethernet and IPv4 addresses
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* @eth_d: Ethernet destination address, NULL if unchanged
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* @eth_s: Ethernet source address, NULL if unchanged
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* @ip_da: Pointer to IPv4 destination address, NULL if unchanged
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*/
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void tcp_update_l2_buf(unsigned char *eth_d, unsigned char *eth_s,
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uint32_t *ip_da)
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{
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int i;
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for (i = 0; i < TCP_TAP_FRAMES; i++) {
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struct tcp4_l2_buf_t *b4 = &tcp4_l2_buf[i];
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struct tcp6_l2_buf_t *b6 = &tcp6_l2_buf[i];
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if (eth_d) {
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memcpy(b4->eh.h_dest, eth_d, ETH_ALEN);
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memcpy(b6->eh.h_dest, eth_d, ETH_ALEN);
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}
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if (eth_s) {
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memcpy(b4->eh.h_source, eth_s, ETH_ALEN);
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memcpy(b6->eh.h_source, eth_s, ETH_ALEN);
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}
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if (ip_da) {
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b4->iph.daddr = *ip_da;
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if (!i) {
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b4->iph.saddr = 0;
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b4->iph.tot_len = 0;
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b4->iph.check = 0;
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b4->psum = sum_16b(&b4->iph, 20);
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b4->tsum = ((*ip_da >> 16) & 0xffff) +
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(*ip_da & 0xffff) +
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htons(IPPROTO_TCP);
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} else {
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b4->psum = tcp4_l2_buf[0].psum;
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b4->tsum = tcp4_l2_buf[0].tsum;
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}
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}
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}
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}
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/**
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* tcp_sock4_iov_init() - Initialise scatter-gather L2 buffers for IPv4 sockets
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*/
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static void tcp_sock4_iov_init(void)
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{
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struct iovec *iov;
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int i;
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tcp4_l2_iov_sock[0].iov_base = tcp_buf_discard;
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for (i = 0, iov = tcp4_l2_iov_sock + 1; i < TCP_TAP_FRAMES;
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i++, iov++) {
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iov->iov_base = &tcp4_l2_buf[i].data;
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iov->iov_len = MSS_DEFAULT;
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}
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tcp4_l2_mh_sock.msg_iov = tcp4_l2_iov_sock;
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for (i = 0, iov = tcp4_l2_iov_tap; i < TCP_TAP_FRAMES; i++, iov++) {
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iov->iov_base = &tcp4_l2_buf[i].vnet_len;
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iov->iov_len = MSS_DEFAULT;
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}
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}
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/**
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* tcp_sock6_iov_init() - Initialise scatter-gather L2 buffers for IPv6 sockets
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*/
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static void tcp_sock6_iov_init(void)
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{
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struct iovec *iov;
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int i;
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tcp6_l2_iov_sock[0].iov_base = tcp_buf_discard;
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for (i = 0, iov = tcp6_l2_iov_sock + 1; i < TCP_TAP_FRAMES;
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i++, iov++) {
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iov->iov_base = &tcp6_l2_buf[i].data;
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iov->iov_len = MSS_DEFAULT;
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}
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tcp6_l2_mh_sock.msg_iov = tcp6_l2_iov_sock;
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for (i = 0, iov = tcp6_l2_iov_tap; i < TCP_TAP_FRAMES; i++, iov++) {
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iov->iov_base = &tcp6_l2_buf[i].vnet_len;
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iov->iov_len = MSS_DEFAULT;
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}
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}
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/**
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* tcp_opt_get() - Get option, and value if any, from TCP header
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* @th: Pointer to TCP header
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@ -846,6 +1085,7 @@ static int tcp_send_to_tap(struct ctx *c, struct tcp_tap_conn *conn,
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err = 0;
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info.tcpi_bytes_acked = conn->tcpi_acked_last;
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info.tcpi_snd_wnd = conn->tcpi_snd_wnd;
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info.tcpi_snd_wscale = conn->ws;
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} else {
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err = getsockopt(conn->sock, SOL_TCP, TCP_INFO, &info, &sl);
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if (err && !(flags & RST)) {
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@ -979,8 +1219,19 @@ static void tcp_clamp_window(struct tcp_tap_conn *conn, struct tcphdr *th,
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} else {
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unsigned int window = ntohs(th->window) << conn->ws;
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if (conn->tap_window == window && conn->window_clamped)
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return;
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if (conn->window_clamped) {
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if (conn->tap_window == window)
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return;
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/* Discard +/- 1% updates to spare some syscalls. */
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if ((window > conn->tap_window &&
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window * 99 / 100 < conn->tap_window) ||
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(window < conn->tap_window &&
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window * 101 / 100 > conn->tap_window)) {
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conn->tap_window = window;
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return;
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}
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}
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conn->tap_window = window;
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if (window < 256)
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@ -1087,6 +1338,10 @@ static void tcp_conn_from_tap(struct ctx *c, int af, void *addr,
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conn->mss_guest = tcp_opt_get(th, len, OPT_MSS, NULL, NULL);
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if (conn->mss_guest < 0)
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conn->mss_guest = MSS_DEFAULT;
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if (c->mode == MODE_PASST && c->v6 && conn->mss_guest > SHRT_MAX)
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conn->mss_guest = SHRT_MAX;
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sl = sizeof(conn->mss_guest);
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setsockopt(s, SOL_TCP, TCP_MAXSEG, &conn->mss_guest, sl);
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@ -1271,6 +1526,7 @@ static void tcp_sock_consume(struct tcp_tap_conn *conn, uint32_t ack_seq)
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* needed from the buffer, and we won't rewind back to a lower ACK
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* sequence.
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*/
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if (to_ack > MAX_WINDOW)
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return;
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@ -1286,69 +1542,272 @@ static void tcp_sock_consume(struct tcp_tap_conn *conn, uint32_t ack_seq)
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* @conn: Connection pointer
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* @now: Current timestamp
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*
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* Return: negative on connection reset, 1 on pending data, 0 otherwise
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* Return: negative on connection reset, 0 otherwise
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*/
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static int tcp_data_from_sock(struct ctx *c, struct tcp_tap_conn *conn,
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struct timespec *now)
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{
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uint32_t offset = conn->seq_to_tap - conn->seq_ack_from_tap;
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int len, err, left, send, s = conn->sock;
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int mss_tap, fill_bufs, send_bufs = 0, last_len, msg_len, iov_rem = 0;
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int *buf_mss, *buf_mss_nr_set, *buf_mss_tap, *buf_mss_tap_nr_set;
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int send, len, plen, v4 = IN6_IS_ADDR_V4MAPPED(&conn->a.a6);
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socklen_t sl = sizeof(struct tcp_info);
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struct mmsghdr *mh = tcp_l2_mh_tap;
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int s = conn->sock, i, ret = 0;
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struct iovec *iov, *iov_tap;
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uint32_t already_sent;
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struct tcp_info info;
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if (!conn->tap_window || offset >= conn->tap_window)
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already_sent = conn->seq_to_tap - conn->seq_ack_from_tap;
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if (!conn->tap_window || already_sent >= conn->tap_window)
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return 1;
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len = recv(s, sock_buf,
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/* TODO: Drop 64KiB limit (needed for responsiveness) once
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* tap-side coalescing and zero-copy are fully implemented.
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*/
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MIN(64 * 1024, conn->tap_window),
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/* Don't dequeue until acknowledged by guest */
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MSG_DONTWAIT | MSG_PEEK);
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fill_bufs = DIV_ROUND_UP(conn->tap_window - already_sent,
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conn->mss_guest);
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if (fill_bufs > TCP_TAP_FRAMES)
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fill_bufs = TCP_TAP_FRAMES;
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if (len < 0) {
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if (errno != EAGAIN && errno != EWOULDBLOCK) {
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tcp_rst(c, conn);
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return -errno;
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}
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return 0;
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/* Adjust iovec length for recvmsg() based on what was set last time. */
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if (v4) {
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iov = tcp4_l2_iov_sock + 1;
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buf_mss = &tcp4_l2_buf_mss;
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buf_mss_nr_set = &tcp4_l2_buf_mss_nr_set;
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} else {
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iov = tcp6_l2_iov_sock + 1;
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buf_mss = &tcp6_l2_buf_mss;
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buf_mss_nr_set = &tcp6_l2_buf_mss_nr_set;
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}
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if (*buf_mss != conn->mss_guest) {
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for (i = 0; i < fill_bufs; i++)
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iov[i].iov_len = conn->mss_guest;
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*buf_mss = conn->mss_guest;
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*buf_mss_nr_set = fill_bufs - 1;
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} else if (*buf_mss_nr_set < fill_bufs) {
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for (i = *buf_mss_nr_set; i < fill_bufs; i++)
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iov[i].iov_len = conn->mss_guest;
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*buf_mss_nr_set = fill_bufs - 1;
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}
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if (len == 0) {
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if (conn->state >= ESTABLISHED_SOCK_FIN)
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return 0;
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/* First buffer is to discard data, last one may be partially filled. */
|
||||
iov[-1].iov_len = already_sent;
|
||||
iov_rem = (conn->tap_window - already_sent) % conn->mss_guest;
|
||||
if (iov_rem && fill_bufs < TCP_TAP_FRAMES)
|
||||
iov[fill_bufs - 1].iov_len = iov_rem;
|
||||
if (v4)
|
||||
tcp4_l2_mh_sock.msg_iovlen = fill_bufs + 1;
|
||||
else
|
||||
tcp6_l2_mh_sock.msg_iovlen = fill_bufs + 1;
|
||||
|
||||
tcp_tap_state(conn, ESTABLISHED_SOCK_FIN);
|
||||
if ((err = tcp_send_to_tap(c, conn, FIN | ACK, NULL, 0)))
|
||||
return err;
|
||||
/* Don't dequeue until acknowledged by guest. */
|
||||
len = recvmsg(s, v4 ? &tcp4_l2_mh_sock : &tcp6_l2_mh_sock, MSG_PEEK);
|
||||
if (len < 0)
|
||||
goto err;
|
||||
|
||||
left = 0;
|
||||
if (!len)
|
||||
goto zero_len;
|
||||
|
||||
send = len - already_sent;
|
||||
if (send <= 0)
|
||||
goto out_restore_iov;
|
||||
|
||||
send_bufs = DIV_ROUND_UP(send, conn->mss_guest);
|
||||
last_len = send - (send_bufs - 1) * conn->mss_guest;
|
||||
|
||||
/* Adjust iovec length for sending based on what was set last time. */
|
||||
if (v4) {
|
||||
mss_tap = conn->mss_guest +
|
||||
offsetof(struct tcp4_l2_buf_t, data) -
|
||||
offsetof(struct tcp4_l2_buf_t, vnet_len);
|
||||
|
||||
iov_tap = tcp4_l2_iov_tap;
|
||||
buf_mss_tap = &tcp4_l2_buf_mss_tap;
|
||||
buf_mss_tap_nr_set = &tcp4_l2_buf_mss_tap_nr_set;
|
||||
} else {
|
||||
mss_tap = conn->mss_guest +
|
||||
offsetof(struct tcp6_l2_buf_t, data) -
|
||||
offsetof(struct tcp6_l2_buf_t, vnet_len);
|
||||
|
||||
iov_tap = tcp6_l2_iov_tap;
|
||||
buf_mss_tap = &tcp6_l2_buf_mss_tap;
|
||||
buf_mss_tap_nr_set = &tcp6_l2_buf_mss_tap_nr_set;
|
||||
}
|
||||
if (*buf_mss_tap != mss_tap) {
|
||||
for (i = 0; i < send_bufs; i++)
|
||||
iov_tap[i].iov_len = mss_tap;
|
||||
*buf_mss_tap = mss_tap;
|
||||
*buf_mss_tap_nr_set = send_bufs;
|
||||
} else if (*buf_mss_tap_nr_set < send_bufs) {
|
||||
for (i = *buf_mss_tap_nr_set; i < send_bufs; i++)
|
||||
iov_tap[i].iov_len = mss_tap;
|
||||
*buf_mss_tap_nr_set = send_bufs;
|
||||
}
|
||||
|
||||
iov_tap[send_bufs - 1].iov_len = mss_tap - conn->mss_guest + last_len;
|
||||
|
||||
/* Likely, some new data was acked too. */
|
||||
if (conn->seq_from_tap != conn->seq_ack_to_tap) {
|
||||
if (getsockopt(conn->sock, SOL_TCP, TCP_INFO, &info, &sl))
|
||||
goto err;
|
||||
|
||||
conn->tcpi_acked_last = info.tcpi_bytes_acked;
|
||||
conn->seq_ack_to_tap = info.tcpi_bytes_acked +
|
||||
conn->seq_init_from_tap;
|
||||
} else {
|
||||
info.tcpi_snd_wscale = conn->ws;
|
||||
info.tcpi_snd_wnd = conn->tcpi_snd_wnd;
|
||||
}
|
||||
|
||||
if (v4)
|
||||
mh->msg_hdr.msg_iov = tcp4_l2_iov_tap;
|
||||
else
|
||||
mh->msg_hdr.msg_iov = tcp6_l2_iov_tap;
|
||||
mh->msg_hdr.msg_iovlen = 0;
|
||||
plen = conn->mss_guest;
|
||||
msg_len = 0;
|
||||
for (i = 0; i < send_bufs; i++) {
|
||||
int iov_len, ip_len;
|
||||
|
||||
if (i == send_bufs - 1)
|
||||
plen = last_len;
|
||||
|
||||
if (v4) {
|
||||
struct tcp4_l2_buf_t *b = &tcp4_l2_buf[i];
|
||||
|
||||
ip_len = plen + sizeof(struct iphdr) +
|
||||
sizeof(struct tcphdr);
|
||||
|
||||
b->iph.tot_len = htons(ip_len);
|
||||
b->iph.saddr = conn->a.a4.a.s_addr;
|
||||
b->iph.daddr = c->addr4_seen;
|
||||
if (!i || i == send_bufs - 1)
|
||||
tcp_update_check_ip4(b);
|
||||
else
|
||||
b->iph.check = tcp4_l2_buf[0].iph.check;
|
||||
|
||||
b->th.source = htons(conn->sock_port);
|
||||
b->th.dest = htons(conn->tap_port);
|
||||
b->th.seq = htonl(conn->seq_to_tap);
|
||||
b->th.ack_seq = htonl(conn->seq_ack_to_tap);
|
||||
|
||||
if (conn->no_snd_wnd) {
|
||||
b->th.window = htons(WINDOW_DEFAULT);
|
||||
} else {
|
||||
b->th.window = htons(info.tcpi_snd_wnd >>
|
||||
info.tcpi_snd_wscale);
|
||||
conn->tcpi_snd_wnd = info.tcpi_snd_wnd;
|
||||
}
|
||||
|
||||
tcp_update_check_tcp4(b);
|
||||
|
||||
if (c->mode == MODE_PASTA) {
|
||||
ip_len += sizeof(struct ethhdr);
|
||||
write(c->fd_tap, &b->eh, ip_len);
|
||||
pcap((char *)&b->eh, ip_len);
|
||||
|
||||
conn->seq_to_tap += plen;
|
||||
continue;
|
||||
}
|
||||
|
||||
b->vnet_len = htonl(sizeof(struct ethhdr) + ip_len);
|
||||
} else {
|
||||
struct tcp6_l2_buf_t *b = &tcp6_l2_buf[i];
|
||||
uint32_t flow = conn->seq_init_to_tap;
|
||||
|
||||
ip_len = plen + sizeof(struct ipv6hdr) +
|
||||
sizeof(struct tcphdr);
|
||||
|
||||
b->ip6h.payload_len = htons(plen +
|
||||
sizeof(struct tcphdr));
|
||||
b->ip6h.saddr = conn->a.a6;
|
||||
if (IN6_IS_ADDR_LINKLOCAL(&b->ip6h.saddr))
|
||||
b->ip6h.daddr = c->addr6_ll_seen;
|
||||
else
|
||||
b->ip6h.daddr = c->addr6_seen;
|
||||
|
||||
b->th.source = htons(conn->sock_port);
|
||||
b->th.dest = htons(conn->tap_port);
|
||||
b->th.seq = htonl(conn->seq_to_tap);
|
||||
b->th.ack_seq = htonl(conn->seq_ack_to_tap);
|
||||
|
||||
if (conn->no_snd_wnd) {
|
||||
b->th.window = htons(WINDOW_DEFAULT);
|
||||
} else {
|
||||
b->th.window = htons(info.tcpi_snd_wnd >>
|
||||
info.tcpi_snd_wscale);
|
||||
conn->tcpi_snd_wnd = info.tcpi_snd_wnd;
|
||||
}
|
||||
|
||||
memset(b->ip6h.flow_lbl, 0, 3);
|
||||
tcp_update_check_tcp6(b);
|
||||
|
||||
b->ip6h.flow_lbl[0] = (flow >> 16) & 0xf;
|
||||
b->ip6h.flow_lbl[1] = (flow >> 8) & 0xff;
|
||||
b->ip6h.flow_lbl[2] = (flow >> 0) & 0xff;
|
||||
|
||||
if (c->mode == MODE_PASTA) {
|
||||
ip_len += sizeof(struct ethhdr);
|
||||
write(c->fd_tap, &b->eh, ip_len);
|
||||
pcap((char *)&b->eh, ip_len);
|
||||
|
||||
conn->seq_to_tap += plen;
|
||||
continue;
|
||||
}
|
||||
|
||||
b->vnet_len = htonl(sizeof(struct ethhdr) + ip_len);
|
||||
}
|
||||
|
||||
iov_len = sizeof(uint32_t) + sizeof(struct ethhdr) + ip_len;
|
||||
|
||||
/* Switch to a new message if this one is too long for qemu. */
|
||||
if (msg_len && msg_len + iov_len > SHRT_MAX) {
|
||||
mh++;
|
||||
mh->msg_hdr.msg_iovlen = 0;
|
||||
msg_len = 0;
|
||||
if (v4)
|
||||
mh->msg_hdr.msg_iov = &tcp4_l2_iov_tap[i];
|
||||
else
|
||||
mh->msg_hdr.msg_iov = &tcp6_l2_iov_tap[i];
|
||||
}
|
||||
mh->msg_hdr.msg_iovlen++;
|
||||
msg_len += iov_len;
|
||||
|
||||
conn->seq_to_tap += plen;
|
||||
}
|
||||
|
||||
if (c->mode == MODE_PASTA)
|
||||
goto out;
|
||||
|
||||
sendmmsg(c->fd_tap, tcp_l2_mh_tap, mh - tcp_l2_mh_tap + 1,
|
||||
MSG_NOSIGNAL | MSG_DONTWAIT);
|
||||
pcapmm(tcp_l2_mh_tap, mh - tcp_l2_mh_tap + 1);
|
||||
|
||||
goto out;
|
||||
|
||||
err:
|
||||
if (errno != EAGAIN && errno != EWOULDBLOCK) {
|
||||
tcp_rst(c, conn);
|
||||
ret = -errno;
|
||||
}
|
||||
goto out_restore_iov;
|
||||
|
||||
left = len - offset;
|
||||
while (left && (offset + conn->mss_guest <= conn->tap_window)) {
|
||||
if (left < conn->mss_guest)
|
||||
send = left;
|
||||
else
|
||||
send = conn->mss_guest;
|
||||
zero_len:
|
||||
if (conn->state >= ESTABLISHED_SOCK_FIN)
|
||||
goto out_restore_iov;
|
||||
|
||||
if (offset + send > MAX_WINDOW) {
|
||||
tcp_rst(c, conn);
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
err = tcp_send_to_tap(c, conn, 0, sock_buf + offset, send);
|
||||
if (err)
|
||||
return err;
|
||||
|
||||
offset += send;
|
||||
left -= send;
|
||||
}
|
||||
tcp_tap_state(conn, ESTABLISHED_SOCK_FIN);
|
||||
tcp_send_to_tap(c, conn, FIN | ACK, NULL, 0);
|
||||
goto out_restore_iov;
|
||||
|
||||
out:
|
||||
conn->ts_sock = *now;
|
||||
|
||||
return !!left;
|
||||
out_restore_iov:
|
||||
if (iov_rem)
|
||||
iov[fill_bufs - 1].iov_len = conn->mss_guest;
|
||||
if (send_bufs)
|
||||
iov_tap[send_bufs - 1].iov_len = mss_tap;
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/**
|
||||
|
|
@ -1446,6 +1905,11 @@ int tcp_tap_handler(struct ctx *c, int af, void *addr,
|
|||
if (conn->mss_guest < 0)
|
||||
conn->mss_guest = MSS_DEFAULT;
|
||||
|
||||
/* Don't upset qemu */
|
||||
if (c->mode == MODE_PASST && c->v6 &&
|
||||
conn->mss_guest > SHRT_MAX)
|
||||
conn->mss_guest = SHRT_MAX;
|
||||
|
||||
ws = tcp_opt_get(th, len, OPT_WS, NULL, NULL);
|
||||
if (ws > MAX_WS) {
|
||||
if (tcp_send_to_tap(c, conn, RST, NULL, 0))
|
||||
|
|
|
|||
2
tcp.h
2
tcp.h
|
|
@ -14,6 +14,8 @@ int tcp_tap_handler(struct ctx *c, int af, void *addr,
|
|||
struct tap_msg *msg, int count, struct timespec *now);
|
||||
int tcp_sock_init(struct ctx *c);
|
||||
void tcp_timer(struct ctx *c, struct timespec *ts);
|
||||
void tcp_update_l2_buf(unsigned char *eth_d, unsigned char *eth_s,
|
||||
uint32_t *ip_da);
|
||||
|
||||
/**
|
||||
* union tcp_epoll_ref - epoll reference portion for TCP connections
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user