1 /* 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright 2021 Lutz Donnerhacke 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 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above 13 * copyright notice, this list of conditions and the following 14 * disclaimer in the documentation and/or other materials provided 15 * with the distribution. 16 * 3. Neither the name of the copyright holder nor the names of its 17 * contributors may be used to endorse or promote products derived 18 * from this software without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 21 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 22 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 23 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 24 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS 25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 26 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 27 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 29 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR 30 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 31 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 #include <stdio.h> 35 #include <stdlib.h> 36 37 #include <netinet/in.h> 38 39 #include "util.h" 40 41 /* common ip ranges */ 42 struct in_addr masq = { htonl(0x01020304) }; 43 struct in_addr pub = { htonl(0x0102dead) }; 44 struct in_addr prv1 = { htonl(0x0a00dead) }; 45 struct in_addr prv2 = { htonl(0xac10dead) }; 46 struct in_addr prv3 = { htonl(0xc0a8dead) }; 47 struct in_addr cgn = { htonl(0x6440dead) }; 48 struct in_addr ext = { htonl(0x12345678) }; 49 struct in_addr ANY_ADDR = { 0 }; 50 51 #define REQUIRE(x) do { \ 52 if (!(x)) { \ 53 fprintf(stderr, "Failed in %s %s:%d.\n",\ 54 __FUNCTION__, __FILE__, __LINE__); \ 55 exit(-1); \ 56 } \ 57 } while(0) 58 59 int 60 randcmp(const void *a, const void *b) 61 { 62 int res, r = rand(); 63 64 (void)a; 65 (void)b; 66 res = (r/4 < RAND_MAX/9) ? 1 67 : (r/5 < RAND_MAX/9) ? 0 68 : -1; 69 return (res); 70 } 71 72 void 73 hexdump(void *p, size_t len) 74 { 75 size_t i; 76 unsigned char *c = p; 77 78 for (i = 0; i < len; i++) { 79 printf(" %02x", c[i]); 80 switch (i & 0xf) { 81 case 0xf: printf("\n"); break; 82 case 0x7: printf(" "); break; 83 default: break; 84 } 85 } 86 if ((i & 0xf) != 0x0) 87 printf("\n"); 88 } 89 90 struct ip * 91 ip_packet(u_char protocol, size_t len) 92 { 93 struct ip * p; 94 95 REQUIRE(len >= 64 && len <= IP_MAXPACKET); 96 97 p = calloc(1, len); 98 REQUIRE(p != NULL); 99 100 p->ip_v = IPVERSION; 101 p->ip_hl = sizeof(*p)/4; 102 p->ip_len = htons(len); 103 p->ip_ttl = IPDEFTTL; 104 p->ip_p = protocol; 105 REQUIRE(p->ip_hl == 5); 106 107 return (p); 108 } 109 110 struct udphdr * 111 set_udp(struct ip *p, u_short sport, u_short dport) { 112 uint32_t *up = (void *)p; 113 struct udphdr *u = (void *)&(up[p->ip_hl]); 114 int payload = ntohs(p->ip_len) - 4*p->ip_hl; 115 116 REQUIRE(payload >= (int)sizeof(*u)); 117 p->ip_p = IPPROTO_UDP; 118 u->uh_sport = htons(sport); 119 u->uh_dport = htons(dport); 120 u->uh_ulen = htons(payload); 121 return (u); 122 } 123