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 pub2 = { htonl(0x0102beef) }; 45 struct in_addr prv1 = { htonl(0x0a00dead) }; 46 struct in_addr prv2 = { htonl(0xac10dead) }; 47 struct in_addr prv3 = { htonl(0xc0a8dead) }; 48 struct in_addr cgn = { htonl(0x6440dead) }; 49 struct in_addr ext = { htonl(0x12345678) }; 50 struct in_addr ANY_ADDR = { 0 }; 51 52 #define REQUIRE(x) do { \ 53 if (!(x)) { \ 54 fprintf(stderr, "Failed in %s %s:%d.\n",\ 55 __FUNCTION__, __FILE__, __LINE__); \ 56 exit(-1); \ 57 } \ 58 } while(0) 59 60 int 61 randcmp(const void *a, const void *b) 62 { 63 int res, r = rand(); 64 65 (void)a; 66 (void)b; 67 res = (r/4 < RAND_MAX/9) ? 1 68 : (r/5 < RAND_MAX/9) ? 0 69 : -1; 70 return (res); 71 } 72 73 void 74 hexdump(void *p, size_t len) 75 { 76 size_t i; 77 unsigned char *c = p; 78 79 for (i = 0; i < len; i++) { 80 printf(" %02x", c[i]); 81 switch (i & 0xf) { 82 case 0xf: printf("\n"); break; 83 case 0x7: printf(" "); break; 84 default: break; 85 } 86 } 87 if ((i & 0xf) != 0x0) 88 printf("\n"); 89 } 90 91 struct ip * 92 ip_packet(u_char protocol, size_t len) 93 { 94 struct ip * p; 95 96 REQUIRE(len >= 64 && len <= IP_MAXPACKET); 97 98 p = calloc(1, len); 99 REQUIRE(p != NULL); 100 101 p->ip_v = IPVERSION; 102 p->ip_hl = sizeof(*p)/4; 103 p->ip_len = htons(len); 104 p->ip_ttl = IPDEFTTL; 105 p->ip_p = protocol; 106 REQUIRE(p->ip_hl == 5); 107 108 return (p); 109 } 110 111 struct udphdr * 112 set_udp(struct ip *p, u_short sport, u_short dport) { 113 int hlen = p->ip_hl << 2; 114 struct udphdr *u = (struct udphdr *)((uintptr_t)p + hlen); 115 int payload = ntohs(p->ip_len) - hlen; 116 117 REQUIRE(payload >= (int)sizeof(*u)); 118 p->ip_p = IPPROTO_UDP; 119 u->uh_sport = htons(sport); 120 u->uh_dport = htons(dport); 121 u->uh_ulen = htons(payload); 122 return (u); 123 } 124