/* * Copyright (C) 1995-2001 by Darren Reed. * * See the IPFILTER.LICENCE file for details on licencing. * * Copyright 2006 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ #if !defined(lint) static const char sccsid[] = "@(#)ipft_tx.c 1.7 6/5/96 (C) 1993 Darren Reed"; static const char rcsid[] = "@(#)$Id: ipft_tx.c,v 1.15.2.3 2005/06/18 02:41:34 darrenr Exp $"; #endif #include #include "ipf.h" #include "ipt.h" #ifndef linux #include #endif #include extern int opts; static char *tx_proto = ""; static int text_open __P((char *)), text_close __P((void)); static int text_readip __P((char *, int, char **, int *)); static int parseline __P((char *, ip_t *, char **, int *)); static char myflagset[] = "FSRPAUEC"; static u_char myflags[] = { TH_FIN, TH_SYN, TH_RST, TH_PUSH, TH_ACK, TH_URG, TH_ECN, TH_CWR }; struct ipread iptext = { text_open, text_close, text_readip, R_DO_CKSUM }; static FILE *tfp = NULL; static int tfd = -1; static u_32_t tx_hostnum __P((char *, int *)); static u_short tx_portnum __P((char *)); /* * returns an ip address as a long var as a result of either a DNS lookup or * straight inet_addr() call */ static u_32_t tx_hostnum(host, resolved) char *host; int *resolved; { i6addr_t ipa; *resolved = 0; if (!strcasecmp("any", host)) return 0L; if (ISDIGIT(*host)) return inet_addr(host); if (gethost(host, &ipa, 0) == -1) { *resolved = -1; fprintf(stderr, "can't resolve hostname: %s\n", host); return 0; } return ipa.in4_addr; } /* * find the port number given by the name, either from getservbyname() or * straight atoi() */ static u_short tx_portnum(name) char *name; { struct servent *sp, *sp2; u_short p1 = 0; if (ISDIGIT(*name)) return (u_short)atoi(name); if (!tx_proto) tx_proto = "tcp/udp"; if (strcasecmp(tx_proto, "tcp/udp")) { sp = getservbyname(name, tx_proto); if (sp) return ntohs(sp->s_port); (void) fprintf(stderr, "unknown service \"%s\".\n", name); return 0; } sp = getservbyname(name, "tcp"); if (sp) p1 = sp->s_port; sp2 = getservbyname(name, "udp"); if (!sp || !sp2) { (void) fprintf(stderr, "unknown tcp/udp service \"%s\".\n", name); return 0; } if (p1 != sp2->s_port) { (void) fprintf(stderr, "%s %d/tcp is a different port to ", name, p1); (void) fprintf(stderr, "%s %d/udp\n", name, sp->s_port); return 0; } return ntohs(p1); } char *tx_icmptypes[] = { "echorep", (char *)NULL, (char *)NULL, "unreach", "squench", "redir", (char *)NULL, (char *)NULL, "echo", "routerad", "routersol", "timex", "paramprob", "timest", "timestrep", "inforeq", "inforep", "maskreq", "maskrep", "END" }; static int text_open(fname) char *fname; { if (tfp && tfd != -1) { rewind(tfp); return tfd; } if (!strcmp(fname, "-")) { tfd = 0; tfp = stdin; } else { tfd = open(fname, O_RDONLY); if (tfd != -1) tfp = fdopen(tfd, "r"); } return tfd; } static int text_close() { int cfd = tfd; tfd = -1; return close(cfd); } static int text_readip(buf, cnt, ifn, dir) char *buf, **ifn; int cnt, *dir; { register char *s; char line[513]; *ifn = NULL; while (fgets(line, sizeof(line)-1, tfp)) { if ((s = strchr(line, '\n'))) *s = '\0'; if ((s = strchr(line, '\r'))) *s = '\0'; if ((s = strchr(line, '#'))) *s = '\0'; if (!*line) continue; if (!(opts & OPT_BRIEF)) printf("input: %s\n", line); *ifn = NULL; *dir = 0; if (!parseline(line, (ip_t *)buf, ifn, dir)) #if 0 return sizeof(ip_t) + sizeof(tcphdr_t); #else return sizeof(ip_t); #endif } return -1; } static int parseline(line, ip, ifn, out) char *line; ip_t *ip; char **ifn; int *out; { tcphdr_t th, *tcp = &th; struct icmp icmp, *ic = &icmp; char *cps[20], **cpp, c, ipopts[68]; int i, r; if (*ifn) free(*ifn); bzero((char *)ip, MAX(sizeof(*tcp), sizeof(*ic)) + sizeof(*ip)); bzero((char *)tcp, sizeof(*tcp)); bzero((char *)ic, sizeof(*ic)); bzero(ipopts, sizeof(ipopts)); IP_HL_A(ip, sizeof(*ip) >> 2); IP_V_A(ip, IPVERSION); for (i = 0, cps[0] = strtok(line, " \b\t\r\n"); cps[i] && i < 19; ) cps[++i] = strtok(NULL, " \b\t\r\n"); cpp = cps; if (!*cpp) return 1; c = **cpp; if (!ISALPHA(c) || (TOLOWER(c) != 'o' && TOLOWER(c) != 'i')) { fprintf(stderr, "bad direction \"%s\"\n", *cpp); return 1; } *out = (TOLOWER(c) == 'o') ? 1 : 0; cpp++; if (!*cpp) return 1; if (!strcasecmp(*cpp, "on")) { cpp++; if (!*cpp) return 1; *ifn = strdup(*cpp++); if (!*cpp) return 1; } c = **cpp; ip->ip_len = sizeof(ip_t); if (!strcasecmp(*cpp, "tcp") || !strcasecmp(*cpp, "udp") || !strcasecmp(*cpp, "icmp")) { if (c == 't') { ip->ip_p = IPPROTO_TCP; ip->ip_len += sizeof(struct tcphdr); tx_proto = "tcp"; } else if (c == 'u') { ip->ip_p = IPPROTO_UDP; ip->ip_len += sizeof(struct udphdr); tx_proto = "udp"; } else { ip->ip_p = IPPROTO_ICMP; ip->ip_len += ICMPERR_IPICMPHLEN; tx_proto = "icmp"; } cpp++; } else if (ISDIGIT(**cpp) && !index(*cpp, '.')) { ip->ip_p = atoi(*cpp); cpp++; } else ip->ip_p = IPPROTO_IP; if (!*cpp) return 1; if (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_UDP) { char *last; last = strchr(*cpp, ','); if (!last) { fprintf(stderr, "tcp/udp with no source port\n"); return 1; } *last++ = '\0'; tcp->th_sport = htons(tx_portnum(last)); if (ip->ip_p == IPPROTO_TCP) { tcp->th_win = htons(4096); TCP_OFF_A(tcp, sizeof(*tcp) >> 2); } } ip->ip_src.s_addr = tx_hostnum(*cpp, &r); cpp++; if (!*cpp) return 1; if (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_UDP) { char *last; last = strchr(*cpp, ','); if (!last) { fprintf(stderr, "tcp/udp with no destination port\n"); return 1; } *last++ = '\0'; tcp->th_dport = htons(tx_portnum(last)); } ip->ip_dst.s_addr = tx_hostnum(*cpp, &r); cpp++; if (*cpp && ip->ip_p == IPPROTO_TCP) { char *s, *t; tcp->th_flags = 0; for (s = *cpp; *s; s++) if ((t = strchr(myflagset, *s))) tcp->th_flags |= myflags[t - myflagset]; if (tcp->th_flags) cpp++; if (tcp->th_flags == 0) abort(); if (tcp->th_flags & TH_URG) tcp->th_urp = htons(1); } else if (*cpp && ip->ip_p == IPPROTO_ICMP) { extern char *tx_icmptypes[]; char **s, *t; int i; for (s = tx_icmptypes, i = 0; !*s || strcmp(*s, "END"); s++, i++) if (*s && !strncasecmp(*cpp, *s, strlen(*s))) { ic->icmp_type = i; if ((t = strchr(*cpp, ','))) ic->icmp_code = atoi(t+1); cpp++; break; } } if (*cpp && !strcasecmp(*cpp, "opt")) { u_long olen; cpp++; olen = buildopts(*cpp, ipopts, (IP_HL(ip) - 5) << 2); if (olen) { bcopy(ipopts, (char *)(ip + 1), olen); IP_HL_A(ip, IP_HL(ip) + (olen >> 2)); } } if (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_UDP) bcopy((char *)tcp, ((char *)ip) + (IP_HL(ip) << 2), sizeof(*tcp)); else if (ip->ip_p == IPPROTO_ICMP) bcopy((char *)ic, ((char *)ip) + (IP_HL(ip) << 2), sizeof(*ic)); ip->ip_len = htons(ip->ip_len); return 0; }