tests/net/bpfilter/t_bpfilter.c

   1 /*      $NetBSD: t_bpfilter.c,v 1.6 2012/09/03 21:27:14 alnsn Exp $     */
   2
   3 /*-
   4  * Copyright (c) 2012 The NetBSD Foundation, Inc.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
  16  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  18  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  21  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  */
  27 #include <sys/cdefs.h>
  28 __RCSID("$NetBSD: t_bpfilter.c,v 1.6 2012/09/03 21:27:14 alnsn Exp $");
  29
  30 #include <sys/param.h>
  31 #include <sys/ioctl.h>
  32 #include <sys/socket.h>
  33 #include <sys/mbuf.h>
  34 #include <sys/sysctl.h>
  35 #include <sys/mman.h>
  36 #include <sys/wait.h>
  37 #include <unistd.h>
  38
  39 #include <net/if.h>
  40 #include <net/if_ether.h>
  41 #include <net/bpf.h>
  42
  43 #include <fcntl.h>
  44 #include <stdint.h>
  45 #include <stdio.h>
  46 #include <string.h>
  47
  48 #include <rump/rump.h>
  49 #include <rump/rump_syscalls.h>
  50
  51 /* XXX: atf-c.h has collisions with mbuf */
  52 #undef m_type
  53 #undef m_data
  54 #include <atf-c.h>
  55
  56 #include "../../h_macros.h"
  57 #include "../config/netconfig.c"
  58
  59
  60 #define SNAPLEN UINT32_MAX
  61
  62 #define BMAGIC UINT32_C(0x37)
  63 #define HMAGIC UINT32_C(0xc2c2)
  64 #define WMAGIC UINT32_C(0x7d7d7d7d)
  65
  66 static const char magic_echo_reply_tail[7] = {
  67         BMAGIC,
  68         HMAGIC & 0xff,
  69         HMAGIC & 0xff,
  70         WMAGIC & 0xff,
  71         WMAGIC & 0xff,
  72         WMAGIC & 0xff,
  73         WMAGIC & 0xff
  74 };
  75
  76 /*
  77  * Match ICMP_ECHOREPLY packet with 7 magic bytes at the end.
  78  */
  79 static struct bpf_insn magic_echo_reply_prog[] = {
  80         BPF_STMT(BPF_LD+BPF_ABS+BPF_B,
  81             sizeof(struct ip) + offsetof(struct icmp, icmp_type)),
  82         BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, ICMP_ECHOREPLY, 1, 0),
  83         BPF_STMT(BPF_RET+BPF_K, 0),
  84
  85         BPF_STMT(BPF_LD+BPF_W+BPF_LEN, 0),  /* A <- len   */
  86         BPF_STMT(BPF_ALU+BPF_SUB+BPF_K, 7), /* A <- A - 7 */
  87         BPF_STMT(BPF_MISC+BPF_TAX, 0),      /* X <- A     */
  88
  89         BPF_STMT(BPF_LD+BPF_IND+BPF_B, 0),
  90         BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, BMAGIC, 1, 0),
  91         BPF_STMT(BPF_RET+BPF_K, 0),
  92
  93         BPF_STMT(BPF_LD+BPF_IND+BPF_H, 1),
  94         BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, HMAGIC, 1, 0),
  95         BPF_STMT(BPF_RET+BPF_K, 0),
  96
  97         BPF_STMT(BPF_LD+BPF_IND+BPF_W, 3),
  98         BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, WMAGIC, 1, 0),
  99         BPF_STMT(BPF_RET+BPF_K, 0),
 100
 101         BPF_STMT(BPF_RET+BPF_K, SNAPLEN)
 102 };
 103
 104 static uint16_t
 105 in_cksum(void *data, size_t len)
 106 {
 107         uint16_t *buf = data;
 108         unsigned sum;
 109
 110         for (sum = 0; len > 1; len -= 2)
 111                 sum += *buf++;
 112         if (len)
 113                 sum += *(uint8_t *)buf;
 114
 115         sum = (sum >> 16) + (sum & 0xffff);
 116         sum += (sum >> 16);
 117
 118         return ~sum;
 119 }
 120
 121 /*
 122  * Based on netcfg_rump_pingtest().
 123  */
 124 static bool __unused
 125 pingtest(const char *dst, unsigned int wirelen, const char tail[7])
 126 {
 127         struct timeval tv;
 128         struct sockaddr_in sin;
 129         struct icmp *icmp;
 130         char *pkt;
 131         unsigned int pktsize;
 132         socklen_t slen;
 133         int s;
 134         bool rv = false;
 135
 136         if (wirelen < ETHER_HDR_LEN + sizeof(struct ip))
 137                 return false;
 138
 139         pktsize = wirelen - ETHER_HDR_LEN - sizeof(struct ip);
 140         if (pktsize < sizeof(struct icmp) + 7)
 141                 return false;
 142
 143         s = rump_sys_socket(PF_INET, SOCK_RAW, IPPROTO_ICMP);
 144         if (s == -1)
 145                 return false;
 146
 147         pkt = NULL;
 148
 149         tv.tv_sec = 1;
 150         tv.tv_usec = 0;
 151         if (rump_sys_setsockopt(s, SOL_SOCKET, SO_RCVTIMEO,
 152             &tv, sizeof(tv)) == -1)
 153                 goto out;
 154
 155         memset(&sin, 0, sizeof(sin));
 156         sin.sin_len = sizeof(sin);
 157         sin.sin_family = AF_INET;
 158         sin.sin_addr.s_addr = inet_addr(dst);
 159
 160         pkt = calloc(1, pktsize);
 161         icmp = (struct icmp *)pkt;
 162         if (pkt == NULL)
 163                 goto out;
 164
 165         memcpy(pkt + pktsize - 7, tail, 7);
 166         icmp->icmp_type = ICMP_ECHO;
 167         icmp->icmp_id = htons(37);
 168         icmp->icmp_seq = htons(1);
 169         icmp->icmp_cksum = in_cksum(pkt, pktsize);
 170
 171         slen = sizeof(sin);
 172         if (rump_sys_sendto(s, pkt, pktsize, 0,
 173             (struct sockaddr *)&sin, slen) == -1) {
 174                 goto out;
 175         }
 176
 177         if (rump_sys_recvfrom(s, pkt, pktsize, 0,
 178             (struct sockaddr *)&sin, &slen) == -1)
 179                 goto out;
 180
 181         rv = true;
 182  out:
 183         if (pkt != NULL)
 184                 free(pkt);
 185         rump_sys_close(s);
 186         return rv;
 187 }
 188
 189 static void
 190 magic_ping_test(const char *name, unsigned int wirelen)
 191 {
 192         struct bpf_program prog;
 193         struct bpf_stat bstat;
 194         struct ifreq ifr;
 195         struct timeval tv;
 196         unsigned int bufsize;
 197         bool pinged;
 198         ssize_t n;
 199         char *buf;
 200         pid_t child;
 201         int bpfd;
 202         char token;
 203         int channel[2];
 204
 205         struct bpf_hdr *hdr;
 206
 207         RL(pipe(channel));
 208
 209         prog.bf_len = __arraycount(magic_echo_reply_prog);
 210         prog.bf_insns = magic_echo_reply_prog;
 211
 212         child = fork();
 213         RZ(rump_init());
 214         netcfg_rump_makeshmif(name, ifr.ifr_name);
 215
 216         switch (child) {
 217         case -1:
 218                 atf_tc_fail_errno("fork failed");
 219         case 0:
 220                 netcfg_rump_if(ifr.ifr_name, "10.1.1.10", "255.0.0.0");
 221                 close(channel[0]);
 222                 ATF_CHECK(write(channel[1], "U", 1) == 1);
 223                 close(channel[1]);
 224                 pause();
 225                 return;
 226         default:
 227                 break;
 228         }
 229
 230         netcfg_rump_if(ifr.ifr_name, "10.1.1.20", "255.0.0.0");
 231
 232         RL(bpfd = rump_sys_open("/dev/bpf", O_RDONLY));
 233
 234         tv.tv_sec = 0;
 235         tv.tv_usec = 500;
 236         RL(rump_sys_ioctl(bpfd, BIOCSRTIMEOUT, &tv));
 237
 238         RL(rump_sys_ioctl(bpfd, BIOCGBLEN, &bufsize));
 239         RL(rump_sys_ioctl(bpfd, BIOCSETF, &prog));
 240         RL(rump_sys_ioctl(bpfd, BIOCSETIF, &ifr));
 241
 242         close(channel[1]);
 243         ATF_CHECK(read(channel[0], &token, 1) == 1 && token == 'U');
 244
 245         pinged = pingtest("10.1.1.10", wirelen, magic_echo_reply_tail);
 246         ATF_CHECK(pinged);
 247
 248         buf = malloc(bufsize);
 249         hdr = (struct bpf_hdr *)buf;
 250         ATF_REQUIRE(buf != NULL);
 251         ATF_REQUIRE(bufsize > sizeof(struct bpf_hdr));
 252
 253         n = rump_sys_read(bpfd, buf, bufsize);
 254
 255         ATF_CHECK(n > (int)sizeof(struct bpf_hdr));
 256         ATF_CHECK(hdr->bh_caplen == MIN(SNAPLEN, wirelen));
 257
 258         RL(rump_sys_ioctl(bpfd, BIOCGSTATS, &bstat));
 259         ATF_CHECK(bstat.bs_capt >= 1); /* XXX == 1 */
 260
 261         rump_sys_close(bpfd);
 262         free(buf);
 263
 264         close(channel[0]);
 265
 266         kill(child, SIGKILL);
 267 }
 268
 269 ATF_TC(bpfiltercontig);
 270 ATF_TC_HEAD(bpfiltercontig, tc)
 271 {
 272
 273         atf_tc_set_md_var(tc, "descr", "Checks that bpf program "
 274             "can read bytes from contiguous buffer.");
 275         atf_tc_set_md_var(tc, "timeout", "30");
 276 }
 277
 278 ATF_TC_BODY(bpfiltercontig, tc)
 279 {
 280
 281         magic_ping_test("bpfiltercontig", 128);
 282 }
 283
 284
 285 ATF_TC(bpfiltermchain);
 286 ATF_TC_HEAD(bpfiltermchain, tc)
 287 {
 288
 289         atf_tc_set_md_var(tc, "descr", "Checks that bpf program "
 290             "can read bytes from mbuf chain.");
 291         atf_tc_set_md_var(tc, "timeout", "30");
 292 }
 293
 294 ATF_TC_BODY(bpfiltermchain, tc)
 295 {
 296
 297         magic_ping_test("bpfiltermchain", MINCLSIZE + 1);
 298 }
 299
 300
 301 ATF_TP_ADD_TCS(tp)
 302 {
 303
 304         ATF_TP_ADD_TC(tp, bpfiltercontig);
 305         ATF_TP_ADD_TC(tp, bpfiltermchain);
 306
 307         return atf_no_error();
 308 }