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/*
* Copyright 2013 Google Inc.
* Author: Willem de Bruijn <willemb@google.com>
* Daniel Borkmann <dborkman@redhat.com>
*
* License (GPLv2):
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. * See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef PSOCK_LIB_H
#define PSOCK_LIB_H
#include <sys/types.h>
#include <sys/socket.h>
#include <string.h>
#include <arpa/inet.h>
#include <unistd.h>
#define DATA_LEN 100
#define DATA_CHAR 'a'
#define DATA_CHAR_1 'b'
#define PORT_BASE 8000
#ifndef __maybe_unused
# define __maybe_unused __attribute__ ((__unused__))
#endif
static __maybe_unused void sock_setfilter(int fd, int lvl, int optnum)
{
/* the filter below checks for all of the following conditions that
* are based on the contents of create_payload()
* ether type 0x800 and
* ip proto udp and
* skb->len == DATA_LEN and
* udp[38] == 'a' or udp[38] == 'b'
* It can be generated from the following bpf_asm input:
* ldh [12]
* jne #0x800, drop ; ETH_P_IP
* ldb [23]
* jneq #17, drop ; IPPROTO_UDP
* ld len ; ld skb->len
* jlt #100, drop ; DATA_LEN
* ldb [80]
* jeq #97, pass ; DATA_CHAR
* jne #98, drop ; DATA_CHAR_1
* pass:
* ret #-1
* drop:
* ret #0
*/
struct sock_filter bpf_filter[] = {
{ 0x28, 0, 0, 0x0000000c },
{ 0x15, 0, 8, 0x00000800 },
{ 0x30, 0, 0, 0x00000017 },
{ 0x15, 0, 6, 0x00000011 },
{ 0x80, 0, 0, 0000000000 },
{ 0x35, 0, 4, 0x00000064 },
{ 0x30, 0, 0, 0x00000050 },
{ 0x15, 1, 0, 0x00000061 },
{ 0x15, 0, 1, 0x00000062 },
{ 0x06, 0, 0, 0xffffffff },
{ 0x06, 0, 0, 0000000000 },
};
struct sock_fprog bpf_prog;
if (lvl == SOL_PACKET && optnum == PACKET_FANOUT_DATA)
bpf_filter[5].code = 0x16; /* RET A */
bpf_prog.filter = bpf_filter;
bpf_prog.len = sizeof(bpf_filter) / sizeof(struct sock_filter);
if (setsockopt(fd, lvl, optnum, &bpf_prog,
sizeof(bpf_prog))) {
perror("setsockopt SO_ATTACH_FILTER");
exit(1);
}
}
static __maybe_unused void pair_udp_setfilter(int fd)
{
sock_setfilter(fd, SOL_SOCKET, SO_ATTACH_FILTER);
}
static __maybe_unused void pair_udp_open(int fds[], uint16_t port)
{
struct sockaddr_in saddr, daddr;
fds[0] = socket(PF_INET, SOCK_DGRAM, 0);
fds[1] = socket(PF_INET, SOCK_DGRAM, 0);
if (fds[0] == -1 || fds[1] == -1) {
fprintf(stderr, "ERROR: socket dgram\n");
exit(1);
}
memset(&saddr, 0, sizeof(saddr));
saddr.sin_family = AF_INET;
saddr.sin_port = htons(port);
saddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
memset(&daddr, 0, sizeof(daddr));
daddr.sin_family = AF_INET;
daddr.sin_port = htons(port + 1);
daddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
/* must bind both to get consistent hash result */
if (bind(fds[1], (void *) &daddr, sizeof(daddr))) {
perror("bind");
exit(1);
}
if (bind(fds[0], (void *) &saddr, sizeof(saddr))) {
perror("bind");
exit(1);
}
if (connect(fds[0], (void *) &daddr, sizeof(daddr))) {
perror("connect");
exit(1);
}
}
static __maybe_unused void pair_udp_send_char(int fds[], int num, char payload)
{
char buf[DATA_LEN], rbuf[DATA_LEN];
memset(buf, payload, sizeof(buf));
while (num--) {
/* Should really handle EINTR and EAGAIN */
if (write(fds[0], buf, sizeof(buf)) != sizeof(buf)) {
fprintf(stderr, "ERROR: send failed left=%d\n", num);
exit(1);
}
if (read(fds[1], rbuf, sizeof(rbuf)) != sizeof(rbuf)) {
fprintf(stderr, "ERROR: recv failed left=%d\n", num);
exit(1);
}
if (memcmp(buf, rbuf, sizeof(buf))) {
fprintf(stderr, "ERROR: data failed left=%d\n", num);
exit(1);
}
}
}
static __maybe_unused void pair_udp_send(int fds[], int num)
{
return pair_udp_send_char(fds, num, DATA_CHAR);
}
static __maybe_unused void pair_udp_close(int fds[])
{
close(fds[0]);
close(fds[1]);
}
#endif /* PSOCK_LIB_H */
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