root/tools/testing/selftests/net/psock_lib.h

INCLUDED FROM

DEFINITIONS

1. pair_udp_setfilter
2. pair_udp_open
3. pair_udp_send_char
4. pair_udp_send
5. pair_udp_close

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright 2013 Google Inc.
   4  * Author: Willem de Bruijn <willemb@google.com>
   5  *         Daniel Borkmann <dborkman@redhat.com>
   6  */
   7 
   8 #ifndef PSOCK_LIB_H
   9 #define PSOCK_LIB_H
  10 
  11 #include <sys/types.h>
  12 #include <sys/socket.h>
  13 #include <string.h>
  14 #include <arpa/inet.h>
  15 #include <unistd.h>
  16 
  17 #define DATA_LEN                        100
  18 #define DATA_CHAR                       'a'
  19 #define DATA_CHAR_1                     'b'
  20 
  21 #define PORT_BASE                       8000
  22 
  23 #ifndef __maybe_unused
  24 # define __maybe_unused         __attribute__ ((__unused__))
  25 #endif
  26 
  27 static __maybe_unused void pair_udp_setfilter(int fd)
  28 {
  29         /* the filter below checks for all of the following conditions that
  30          * are based on the contents of create_payload()
  31          *  ether type 0x800 and
  32          *  ip proto udp     and
  33          *  skb->len == DATA_LEN and
  34          *  udp[38] == 'a' or udp[38] == 'b'
  35          * It can be generated from the following bpf_asm input:
  36          *      ldh [12]
  37          *      jne #0x800, drop        ; ETH_P_IP
  38          *      ldb [23]
  39          *      jneq #17, drop          ; IPPROTO_UDP
  40          *      ld len                  ; ld skb->len
  41          *      jlt #100, drop          ; DATA_LEN
  42          *      ldb [80]
  43          *      jeq #97, pass           ; DATA_CHAR
  44          *      jne #98, drop           ; DATA_CHAR_1
  45          *      pass:
  46          *        ret #-1
  47          *      drop:
  48          *        ret #0
  49          */
  50         struct sock_filter bpf_filter[] = {
  51                 { 0x28,  0,  0, 0x0000000c },
  52                 { 0x15,  0,  8, 0x00000800 },
  53                 { 0x30,  0,  0, 0x00000017 },
  54                 { 0x15,  0,  6, 0x00000011 },
  55                 { 0x80,  0,  0, 0000000000 },
  56                 { 0x35,  0,  4, 0x00000064 },
  57                 { 0x30,  0,  0, 0x00000050 },
  58                 { 0x15,  1,  0, 0x00000061 },
  59                 { 0x15,  0,  1, 0x00000062 },
  60                 { 0x06,  0,  0, 0xffffffff },
  61                 { 0x06,  0,  0, 0000000000 },
  62         };
  63         struct sock_fprog bpf_prog;
  64 
  65         bpf_prog.filter = bpf_filter;
  66         bpf_prog.len = sizeof(bpf_filter) / sizeof(struct sock_filter);
  67 
  68         if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &bpf_prog,
  69                        sizeof(bpf_prog))) {
  70                 perror("setsockopt SO_ATTACH_FILTER");
  71                 exit(1);
  72         }
  73 }
  74 
  75 static __maybe_unused void pair_udp_open(int fds[], uint16_t port)
  76 {
  77         struct sockaddr_in saddr, daddr;
  78 
  79         fds[0] = socket(PF_INET, SOCK_DGRAM, 0);
  80         fds[1] = socket(PF_INET, SOCK_DGRAM, 0);
  81         if (fds[0] == -1 || fds[1] == -1) {
  82                 fprintf(stderr, "ERROR: socket dgram\n");
  83                 exit(1);
  84         }
  85 
  86         memset(&saddr, 0, sizeof(saddr));
  87         saddr.sin_family = AF_INET;
  88         saddr.sin_port = htons(port);
  89         saddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
  90 
  91         memset(&daddr, 0, sizeof(daddr));
  92         daddr.sin_family = AF_INET;
  93         daddr.sin_port = htons(port + 1);
  94         daddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
  95 
  96         /* must bind both to get consistent hash result */
  97         if (bind(fds[1], (void *) &daddr, sizeof(daddr))) {
  98                 perror("bind");
  99                 exit(1);
 100         }
 101         if (bind(fds[0], (void *) &saddr, sizeof(saddr))) {
 102                 perror("bind");
 103                 exit(1);
 104         }
 105         if (connect(fds[0], (void *) &daddr, sizeof(daddr))) {
 106                 perror("connect");
 107                 exit(1);
 108         }
 109 }
 110 
 111 static __maybe_unused void pair_udp_send_char(int fds[], int num, char payload)
 112 {
 113         char buf[DATA_LEN], rbuf[DATA_LEN];
 114 
 115         memset(buf, payload, sizeof(buf));
 116         while (num--) {
 117                 /* Should really handle EINTR and EAGAIN */
 118                 if (write(fds[0], buf, sizeof(buf)) != sizeof(buf)) {
 119                         fprintf(stderr, "ERROR: send failed left=%d\n", num);
 120                         exit(1);
 121                 }
 122                 if (read(fds[1], rbuf, sizeof(rbuf)) != sizeof(rbuf)) {
 123                         fprintf(stderr, "ERROR: recv failed left=%d\n", num);
 124                         exit(1);
 125                 }
 126                 if (memcmp(buf, rbuf, sizeof(buf))) {
 127                         fprintf(stderr, "ERROR: data failed left=%d\n", num);
 128                         exit(1);
 129                 }
 130         }
 131 }
 132 
 133 static __maybe_unused void pair_udp_send(int fds[], int num)
 134 {
 135         return pair_udp_send_char(fds, num, DATA_CHAR);
 136 }
 137 
 138 static __maybe_unused void pair_udp_close(int fds[])
 139 {
 140         close(fds[0]);
 141         close(fds[1]);
 142 }
 143 
 144 #endif /* PSOCK_LIB_H */