/* * Copyright (c) 1994 Ugen J.S.Antsilevich * Idea and grammar partially left from: * Copyright (c) 1993 Daniel Boulet * * Redistribution and use in source forms, with and without modification, * are permitted provided that this entire comment appears intact. * * Redistribution in binary form may occur without any restrictions. * Obviously, it would be nice if you gave credit where credit is due * but requiring it would be too onerous. * * This software is provided ``AS IS'' without any warranties of any kind. * * NEW command line interface for IP firewall facility * * $Id: ipfw.c,v 1.16 1995/08/22 00:38:02 gpalmer Exp $ * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define IPFIREWALL #define IPACCT #include #define MAXSTR 25 char progname[MAXSTR]; /* Program name for errors */ char proto_name[MAXSTR]=""; /* Current line protocol */ int s; /* main RAW socket */ int do_resolv=1; /* Would try to resolv all */ int do_short=0; /* Compact output */ int do_acct=0; /* Show packet/byte count */ int ports_ok=0; /* flag allowing ports */ u_short flags=0; /* New entry flags */ #define FW 0x001 /* Firewall action */ #define AC 0x002 /* Accounting action */ #define S_ANY "any" #define IS_TO(x) (!strcmp(x,"to")) #define IS_FROM(x) (!strcmp(x,"from")) #define IS_VIA(x) (!strcmp(x,"via") || !strcmp(x,"on")) #define IS_IPOPT(x) (!strncmp(x,"ipop",4) || !strncmp(x,"opt",3)) #define IS_TCPFLG(x) (!strncmp(x,"tcpf",4) || !strncmp(x,"fla",3)) #define IS_TOKEN(x) (IS_TO(x) || IS_FROM(x) || IS_VIA(x) ||\ IS_IPOPT(x) || IS_TCPFLG(x)) #define IPO_LSRR "ls" #define IPO_SSRR "ss" #define IPO_RR "rr" #define IPO_TS "ts" #define P_AC "a" /* of "accept" for policy action */ #define P_DE "d" /* of "deny" for policy action */ #define CH_FW "f" /* of "firewall" for chains in zero/flush */ #define CH_AC "a" /* of "accounting" for chain in zero/flush/list */ char action_tab[][MAXSTR]={ "addf", #define A_ADDF 0 "delf", #define A_DELF 1 "chkf", #define A_CHKF 2 "adda", #define A_ADDA 3 "dela", #define A_DELA 4 "clr", #define A_CLRA 5 "f", #define A_FLUSH 6 "z", #define A_ZERO 7 "l", #define A_LIST 8 "po", #define A_POLICY 9 "", #define A_NONE 10 }; char type_tab[][MAXSTR]={ "acc", #define T_ACCEPT 0 "pas", #define T_PASS 1 "log", #define T_LOG 2 "rej", #define T_REJECT 3 "lrej", #define T_LREJECT 4 "den", #define T_DENY 5 "lden", #define T_LDENY 6 "sin", #define T_SINGLE 7 "bid", #define T_BIDIR 8 "", #define T_NONE 9 }; char proto_tab[][MAXSTR]={ "all", #define P_ALL 0 "icmp", #define P_ICMP 1 "tcp", #define P_TCP 2 "udp", #define P_UDP 3 "" #define P_NONE 4 }; struct nlist nlf[]={ #define N_FCHAIN 0 { "_ip_fw_chain" }, #define N_POLICY 1 { "_ip_fw_policy" }, "" , }; struct nlist nla[]={ #define N_ACHAIN 0 { "_ip_acct_chain" }, "" , }; int mask_bits(m_ad) struct in_addr m_ad; { int h_fnd=0,h_num=0,i; u_long mask; mask=ntohl(m_ad.s_addr); for (i=0;i>1; } return h_num; } void show_ipfw(chain,c_t) struct ip_fw *chain; int c_t; { char *comma; u_long adrt; struct hostent *he; int i,mb; if (do_short && do_acct) { printf("%8d:%8d ",chain->fw_bcnt,chain->fw_pcnt); } if (do_short) if (c_t==FW) { if (chain->fw_flg & IP_FW_F_ACCEPT) if (chain->fw_flg & IP_FW_F_PRN) printf(" l"); else printf(" a"); else if (chain->fw_flg & IP_FW_F_PRN) if (chain->fw_flg & IP_FW_F_ICMPRPL) printf("lr"); else printf("ld"); else if (chain->fw_flg & IP_FW_F_ICMPRPL) printf(" r"); else printf(" d"); } else { if (chain->fw_flg & IP_FW_F_BIDIR) printf(" b"); else printf(" s"); } else if (c_t==FW) { if (chain->fw_flg & IP_FW_F_ACCEPT) if (chain->fw_flg & IP_FW_F_PRN) printf("log "); else printf("accept "); else if (chain->fw_flg & IP_FW_F_PRN) if (chain->fw_flg & IP_FW_F_ICMPRPL) printf("lreject "); else printf("ldeny "); else if (chain->fw_flg & IP_FW_F_ICMPRPL) printf("reject "); else printf("deny "); } else { if (chain->fw_flg & IP_FW_F_BIDIR) printf("bidir "); else printf("single "); } if (do_short) switch (chain->fw_flg & IP_FW_F_KIND) { case IP_FW_F_ICMP: printf("I "); break; case IP_FW_F_TCP: printf("T "); break; case IP_FW_F_UDP: printf("U "); break; case IP_FW_F_ALL: printf("A "); break; default: break; } else switch (chain->fw_flg & IP_FW_F_KIND) { case IP_FW_F_ICMP: printf("icmp "); break; case IP_FW_F_TCP: printf("tcp "); break; case IP_FW_F_UDP: printf("udp "); break; case IP_FW_F_ALL: printf("all "); break; default: break; } if (do_short) printf("["); else printf("from "); adrt=ntohl(chain->fw_smsk.s_addr); if (adrt==ULONG_MAX && do_resolv) { adrt=(chain->fw_src.s_addr); he=gethostbyaddr((char *)&adrt,sizeof(u_long),AF_INET); if (he==NULL) { printf(inet_ntoa(chain->fw_src)); printf(":"); printf(inet_ntoa(chain->fw_smsk)); } else printf("%s",he->h_name); } else { printf(inet_ntoa(chain->fw_src)); if (adrt!=ULONG_MAX) if ((mb=mask_bits(chain->fw_smsk))>=0) printf("/%d",mb); else { printf(":"); printf(inet_ntoa(chain->fw_smsk)); } } comma = " "; for (i=0;ifw_nsp; i++ ) { printf("%s%d",comma,chain->fw_pts[i]); if (i==0 && (chain->fw_flg & IP_FW_F_SRNG)) comma = ":"; else comma = ","; } if (do_short) printf("]["); else printf(" to "); adrt=ntohl(chain->fw_dmsk.s_addr); if (adrt==ULONG_MAX && do_resolv) { adrt=(chain->fw_dst.s_addr); he=gethostbyaddr((char *)&adrt,sizeof(u_long),AF_INET); if (he==NULL) { printf(inet_ntoa(chain->fw_dst)); printf(":"); printf(inet_ntoa(chain->fw_dmsk)); } else printf("%s",he->h_name); } else { printf(inet_ntoa(chain->fw_dst)); if (adrt!=ULONG_MAX) if ((mb=mask_bits(chain->fw_dmsk))>=0) printf("/%d",mb); else { printf(":"); printf(inet_ntoa(chain->fw_dmsk)); } } comma = " "; for (i=0;ifw_ndp;i++) { printf("%s%d",comma,chain->fw_pts[chain->fw_nsp+i]); if (i==chain->fw_nsp && (chain->fw_flg & IP_FW_F_DRNG)) comma = ":"; else comma = ","; } if (chain->fw_flg&IP_FW_F_IFNAME && chain->fw_via_name[0]) { char ifnb[FW_IFNLEN+1]; if (do_short) printf("]["); else printf(" via "); strncpy(ifnb,chain->fw_via_name,FW_IFNLEN); ifnb[FW_IFNLEN]='\0'; printf("%s%d",ifnb,chain->fw_via_unit); } else if (chain->fw_via_ip.s_addr) { if (do_short) printf("]["); else printf(" via "); printf(inet_ntoa(chain->fw_via_ip)); } if (do_short) printf("]"); if (chain->fw_ipopt && chain->fw_ipnopt) { if (do_short) { printf("["); if (chain->fw_ipopt & IP_FW_IPOPT_SSRR) printf("S"); if (chain->fw_ipnopt & IP_FW_IPOPT_SSRR) printf("s"); if (chain->fw_ipopt & IP_FW_IPOPT_LSRR) printf("L"); if (chain->fw_ipnopt & IP_FW_IPOPT_LSRR) printf("l"); if (chain->fw_ipopt & IP_FW_IPOPT_RR) printf("R"); if (chain->fw_ipnopt & IP_FW_IPOPT_RR) printf("r"); if (chain->fw_ipopt & IP_FW_IPOPT_TS) printf("T"); if (chain->fw_ipnopt & IP_FW_IPOPT_TS) printf("t"); printf("]"); } else { int _opt_printed = 0; #define PRINTOPT(x) {if (_opt_printed) printf(",");\ printf(x); _opt_printed = 1;} printf("ipopt "); if (chain->fw_ipopt & IP_FW_IPOPT_SSRR) PRINTOPT("ssrr"); if (chain->fw_ipnopt & IP_FW_IPOPT_SSRR) PRINTOPT("!ssrr"); if (chain->fw_ipopt & IP_FW_IPOPT_LSRR) PRINTOPT("lsrr"); if (chain->fw_ipnopt & IP_FW_IPOPT_LSRR) PRINTOPT("!lsrr"); if (chain->fw_ipopt & IP_FW_IPOPT_RR) PRINTOPT("rr"); if (chain->fw_ipnopt & IP_FW_IPOPT_RR) PRINTOPT("!rr"); if (chain->fw_ipopt & IP_FW_IPOPT_TS) PRINTOPT("ts"); if (chain->fw_ipnopt & IP_FW_IPOPT_TS) PRINTOPT("!ts"); } } printf("\n"); } list(av) char **av; { kvm_t *kd; static char errb[_POSIX2_LINE_MAX]; struct ip_fw b,*btmp; if (!(kd=kvm_openfiles(NULL,NULL,NULL,O_RDONLY,errb))) { fprintf(stderr,"%s: kvm_openfiles: %s\n", progname,kvm_geterr(kd)); exit(1); } if (*av==NULL || !strncmp(*av,CH_FW,strlen(CH_FW))) { if (kvm_nlist(kd,nlf)<0 || nlf[0].n_type==0) { fprintf(stderr,"%s: kvm_nlist: no namelist in %s\n", progname,getbootfile()); exit(1); } } if (*av==NULL || !strncmp(*av,CH_FW,strlen(CH_FW))) { kvm_read(kd,(u_long)nlf[N_FCHAIN].n_value,&b,sizeof(struct ip_fw)); printf("FireWall chain entries:\n"); while(b.fw_next!=NULL) { btmp=b.fw_next; kvm_read(kd,(u_long)btmp,&b,sizeof(struct ip_fw)); show_ipfw(&b,FW); } } if (*av==NULL || !strncmp(*av,CH_AC,strlen(CH_AC))) { if (kvm_nlist(kd,nla)<0 || nla[0].n_type==0) { fprintf(stderr,"%s: kvm_nlist: no namelist in %s\n", progname,getbootfile()); exit(1); } } if (*av==NULL || !strncmp(*av,CH_AC,strlen(CH_AC))) { kvm_read(kd,(u_long)nla[N_ACHAIN].n_value,&b,sizeof(struct ip_fw)); printf("Accounting chain entries:\n"); while(b.fw_next!=NULL) { btmp=b.fw_next; kvm_read(kd,(u_long)btmp,&b,sizeof(struct ip_fw)); show_ipfw(&b,AC); } } } int get_num(str,tab) char *str; char tab[][MAXSTR]; { int i=0; while(tab[i][0]!='\0') { if (strlen(str)>=strlen(tab[i])) if (!strncmp(str,tab[i],strlen(tab[i]))) return i; i++; } return i; } void show_usage(str) char *str; { if (str) fprintf(stderr,"%s: ERROR - %s\n",progname,str); else fprintf(stderr,"%s: ERROR - bad arguments\n",progname); fprintf(stderr,"See man %s(8) for proper usage.\n",progname); } u_short get_port(str) char *str; { struct servent *sptr; char *end; int port,slen = strlen(str); if ((slen>0) && (strspn(str,"0123456789")==slen)) { port = strtol(str,&end,10); if (*end!='\0') { fprintf(stderr,"%s: illegal port number :%s\n" ,progname,str); exit(1); } if ((port<=0) || (port>USHRT_MAX)) { fprintf(stderr,"%s: port number out of range :%d\n" ,progname,port); exit(1); } return((u_short)port); } else { sptr = getservbyname(str,proto_name); if (!sptr) { fprintf(stderr,"%s: unknown service :%s\n" ,progname,str); exit(1); } return((u_short)ntohs(sptr->s_port)); } } char *findchar(str,c) char *str; char c; { int i,len=strlen(str); for (i=0;ia_max) { fprintf(stderr,"%s: too many ports.\n",progname); exit(1); } *cp='\0'; if ((s_t=(++cp))=='\0') { fprintf(stderr,"%s: bad port list.\n",progname); exit(1); } ports[i++]=get_port(s_h); s_h=s_t; } if (i>a_max) { fprintf(stderr,"%s: too many ports.\n",progname); exit(1); } ports[i]=get_port(s_h); *is_range=0; return (i+1); } void set_entry_ip(str,addr,mask) char *str; struct in_addr *addr,*mask; { char *sm_bit,*sm_oct,*end; int n_bit; struct hostent *hptr; if (!strncmp(str,S_ANY,strlen(S_ANY))) { addr->s_addr=0L; mask->s_addr=0L; return; } if (mask) { (void)strtok(str,"/"); sm_bit=strtok(NULL,""); (void)strtok(str,":"); sm_oct=strtok(NULL,""); } if (!inet_aton(str,addr)) { if (do_resolv) { if (!(hptr=gethostbyname(str))) { fprintf(stderr,"%s: Unknown host name : %s\n", progname,str); exit(1); } else { addr->s_addr=*((u_long *)hptr->h_addr); } } else { fprintf(stderr,"%s: Bad IP : %s\n",progname,str); exit(1); } } /* * This is in case mask we * want to set IP only */ if (!mask) return; mask->s_addr=htonl(ULONG_MAX); if (sm_bit) { n_bit = strtol(sm_bit,&end,10); if (*end!='\0') { show_usage(NULL); exit(1); } if (n_bit<0 || n_bit>sizeof(u_long)*CHAR_BIT) { show_usage(NULL); exit(1); } if (n_bit>0) mask->s_addr= htonl(ULONG_MAX<<(sizeof(u_long)*CHAR_BIT-n_bit)); else mask->s_addr=0L; } if (sm_oct) { if (!inet_aton(sm_oct,mask)) { show_usage(NULL); exit(1); } } /* * Ugh..better of corse do it in kernel so no error possible * but faster here so this way it goes... */ addr->s_addr=mask->s_addr & addr->s_addr; } int set_entry_ifname(str,frwl) char *str; struct ip_fw * frwl; { char name[IFNAMSIZ],buf[IFNAMSIZ],*sptr; short unit; int i; i=0; sptr=str; while(isalpha(*sptr++)) { i++; } *sptr--; if (i==0) return 1; strncpy(name,str,i); name[i]='\0'; unit=(short)atoi(sptr); sprintf(buf,"%s%d",name,unit); if (strcmp(str,buf)) return 1; strncpy(frwl->fw_via_name,name,FW_IFNLEN); frwl->fw_via_unit=unit; return 0; } void set_entry_ipopts(str, frwl) char *str; struct ip_fw *frwl; { char *t_str,*p_str; u_char *optr; p_str = str; while ((t_str = strtok(p_str,",")) != NULL) { p_str = NULL; printf("tstr = %s\n", t_str); if (t_str[0] == '!') { optr = &(frwl->fw_ipnopt); t_str ++; } else optr = &(frwl->fw_ipopt); if (!strncmp(t_str, IPO_LSRR, strlen(IPO_LSRR))) *(optr) |= IP_FW_IPOPT_LSRR; else if (!strncmp(t_str, IPO_SSRR, strlen(IPO_SSRR))) *(optr) |= IP_FW_IPOPT_SSRR; else if (!strncmp(t_str, IPO_RR, strlen(IPO_RR))) *(optr) |= IP_FW_IPOPT_RR; else if (!strncmp(t_str, IPO_TS, strlen(IPO_TS))) *(optr) |= IP_FW_IPOPT_TS; else { fprintf(stderr,"%s: bad ipoption.\n", progname); exit(1); } } } void set_entry(av,frwl) char **av; struct ip_fw * frwl; { int ir; int got_from=0, got_to=0, got_via=0, got_ipopt=0, got_tcpflg=0; #define T_FROM 1 #define T_TO 2 #define T_VIA 3 #define T_IPOPT 4 #define T_TCPFLG 5 int token; /* * This section actually creates * generic entry which matches everything * in this sorry world... */ frwl->fw_nsp=0; frwl->fw_ndp=0; frwl->fw_ipopt = 0; frwl->fw_ipnopt = 0; frwl->fw_via_ip.s_addr=0L; frwl->fw_src.s_addr=0L; frwl->fw_dst.s_addr=0L; frwl->fw_smsk.s_addr=0L; frwl->fw_dmsk.s_addr=0L; get_next: token = 0; if (IS_FROM(*av)) { token = T_FROM; if (got_from) { show_usage("Redefined 'from'."); exit(1); } if (*(++av)==NULL) { show_usage("Missing 'from' specification."); exit(1); } set_entry_ip(*av,&(frwl->fw_src),&(frwl->fw_smsk)); got_from=1; } if (IS_TO(*av)) { token = T_TO; if (got_to) { show_usage("Redefined 'to'."); exit(1); } if (*(++av)==NULL) { show_usage("Missing 'to' specification."); exit(1); } set_entry_ip(*av,&(frwl->fw_dst),&(frwl->fw_dmsk)); got_to = 1; } if (IS_VIA(*av)) { token = T_VIA; if (got_via) { show_usage("Redefined 'via'."); exit(1); } if (*(++av)==NULL) { show_usage("Missing 'via' specification."); exit(1); } /* * Try first to set interface name * from arguments.set_entry_ip() will exit on * wrong argument. */ if (set_entry_ifname(*av,frwl)) set_entry_ip(*av,&(frwl->fw_via_ip),NULL); else flags |= IP_FW_F_IFNAME; got_via = 1; } if (IS_IPOPT(*av)) { token = T_IPOPT; if (got_ipopt) { show_usage("Redefined 'ipoptions'."); exit(1); } if (*(++av)==NULL) { show_usage("Missing 'ipoptions' specification."); exit(1); } set_entry_ipopts(*av, frwl); got_ipopt = 1; } if (*(++av)==NULL) { return; } if (IS_TOKEN(*av)) goto get_next; if (ports_ok && token == T_FROM) { ir = 0; frwl->fw_nsp= set_entry_ports(*av,frwl->fw_pts,IP_FW_MAX_PORTS,&ir); if (ir) flags|=IP_FW_F_SRNG; if (*(++av)==NULL) { return; } } if (ports_ok && token == T_TO) { ir = 0; frwl->fw_ndp= set_entry_ports(*av,&(frwl->fw_pts[frwl->fw_nsp]), (IP_FW_MAX_PORTS-frwl->fw_nsp),&ir); if (ir) flags|=IP_FW_F_DRNG; if (*(++av)==NULL) { return; } } if (token == 0) { show_usage("Unknown token."); exit(1); } goto get_next; } flush(av) char **av; { if (*av==NULL) { if (setsockopt(s,IPPROTO_IP,IP_FW_FLUSH,NULL,0)<0) { fprintf(stderr,"%s: setsockopt failed.\n",progname); exit(1); } else { printf("All firewall entries flushed.\n"); } if (setsockopt(s,IPPROTO_IP,IP_ACCT_FLUSH,NULL,0)<0) { fprintf(stderr,"%s: setsockopt failed.\n",progname); exit(1); } else { printf("All accounting entries flushed.\n"); } exit(0); } if (!strncmp(*av,CH_FW,strlen(CH_FW))) { if (setsockopt(s,IPPROTO_IP,IP_FW_FLUSH,NULL,0)<0) { fprintf(stderr,"%s: setsockopt failed.\n",progname); exit(1); } else { printf("All firewall entries flushed.\n"); exit(0); } } if (!strncmp(*av,CH_AC,strlen(CH_AC))) { if (setsockopt(s,IPPROTO_IP,IP_ACCT_FLUSH,NULL,0)<0) { fprintf(stderr,"%s: setsockopt failed.\n",progname); exit(1); } else { printf("All accounting entries flushed.\n"); exit(0); } } } void policy(av) char **av; { u_short p=0,b; kvm_t *kd; static char errb[_POSIX2_LINE_MAX]; if (*av==NULL || strlen(*av)<=0) { if ( (kd=kvm_openfiles(NULL,NULL,NULL,O_RDONLY,errb)) == NULL) { fprintf(stderr,"%s: kvm_openfiles: %s\n",progname,kvm_geterr(kd)); exit(1); } if (kvm_nlist(kd,nlf) < 0 || nlf[0].n_type == 0) { fprintf(stderr,"%s: kvm_nlist: no namelist in %s\n", progname,getbootfile()); exit(1); } kvm_read(kd,(u_long)nlf[N_POLICY].n_value,&b,sizeof(int)); if (b&IP_FW_P_DENY) printf("Default policy: DENY\n"); else printf("Default policy: ACCEPT\n"); exit(1); } if (!strncmp(*av,P_DE,strlen(P_DE))) p|=IP_FW_P_DENY; else if (!strncmp(*av,P_AC,strlen(P_AC))) p&=~IP_FW_P_DENY; else { fprintf(stderr,"%s: bad policy value.\n",progname); exit(1); } if (setsockopt(s,IPPROTO_IP,IP_FW_POLICY,&p,sizeof(p))<0) { fprintf(stderr,"%s: setsockopt failed.\n",progname); exit(1); } else { if (p&IP_FW_P_DENY) printf("Policy set to DENY.\n"); else printf("Policy set to ACCEPT.\n"); exit(0); } } zero() { if (setsockopt(s,IPPROTO_IP,IP_ACCT_ZERO,NULL,0)<0) { fprintf(stderr,"%s: setsockopt failed.\n",progname); exit(1); } else { printf("Accounting cleared.\n"); exit(0); } } main(ac,av) int ac; char **av; { char ch; extern int optind; int ctl,int_t,is_check=0,int_notdef=0; struct ip_fw frwl; strcpy(progname,*av); s = socket( AF_INET, SOCK_RAW, IPPROTO_RAW ); if ( s < 0 ) { fprintf(stderr,"%s: Can't open raw socket.Must be root to use this programm. \n",progname); exit(1); } if ( ac == 1 ) { show_usage(NULL); exit(1); } while ((ch = getopt(ac, av ,"ans")) != EOF) switch(ch) { case 'a': do_acct=1; break; case 'n': do_resolv=0; break; case 's': do_short=1; break; case '?': default: show_usage(NULL); exit(1); } if (*(av+=optind)==NULL) { show_usage(NULL); exit(1); } switch(get_num(*av,action_tab)) { case A_ADDF: ctl=IP_FW_ADD; int_t=FW; break; case A_DELF: ctl=IP_FW_DEL; int_t=FW; break; case A_CHKF: int_t=FW; is_check=1; break; case A_ADDA: ctl=IP_ACCT_ADD; int_t=AC; break; case A_DELA: ctl=IP_ACCT_DEL; int_t=AC; break; case A_CLRA: ctl=IP_ACCT_CLR; int_t=AC; break; case A_FLUSH: flush(++av); exit(0); /* successful exit */ case A_LIST: list(++av); exit(0); /* successful exit */ case A_ZERO: zero(); exit(0); /* successful exit */ case A_POLICY: policy(++av); exit(0); /* we never get here */ default: int_t=(AC|FW); int_notdef=1; } /* main action switch */ if (is_check) goto proto_switch; if (!int_notdef) if (*(++av)==NULL) { show_usage(NULL); exit(1); } switch(get_num(*av,type_tab)) { case T_LREJECT: flags|=IP_FW_F_PRN; case T_REJECT: flags|=IP_FW_F_ICMPRPL; if (!int_t&FW) { show_usage(NULL); exit(1); } int_t=FW; break; case T_LDENY: flags|=IP_FW_F_PRN; case T_DENY: flags|=0; /* just to show it related to flags */ if (!int_t&FW) { show_usage(NULL); exit(1); } int_t=FW; break; case T_LOG: flags|=IP_FW_F_PRN; case T_ACCEPT: case T_PASS: flags|=IP_FW_F_ACCEPT; if (!int_t&FW) { show_usage(NULL); exit(1); } int_t=FW; break; case T_SINGLE: flags|=0; /* just to show it related to flags */ if (!int_t&AC) { show_usage(NULL); exit(1); } int_t=AC; break; case T_BIDIR: flags|=IP_FW_F_BIDIR; if (!int_t&AC) { show_usage(NULL); exit(1); } int_t=AC; break; default: show_usage(NULL); exit(1); } /* type of switch */ if (int_notdef) { if (int_t==FW) ctl=IP_FW_ADD; if (int_t==AC) ctl=IP_ACCT_ADD; } proto_switch: if (*(++av)==NULL) { show_usage(NULL); exit(1); } switch(get_num(*av,proto_tab)) { case P_ALL: flags|=IP_FW_F_ALL; break; case P_ICMP: flags|=IP_FW_F_ICMP; break; case P_TCP: flags|=IP_FW_F_TCP; ports_ok=1; strcpy(proto_name,"tcp"); break; case P_UDP: flags|=IP_FW_F_UDP; ports_ok=1; strcpy(proto_name,"udp"); break; default: show_usage(NULL); exit(1); } if (*(++av)==NULL) { show_usage(NULL); exit(1); } set_entry(av,&frwl); frwl.fw_flg=flags; if (is_check) { #ifndef disabled fprintf(stderr,"%s: checking disabled.\n",progname); #else struct ip *pkt; struct tcphdr *th; int p_len=sizeof(struct ip)+sizeof(struct tcphdr); pkt=(struct ip*)malloc(p_len); pkt->ip_v = IPVERSION; pkt->ip_hl = sizeof(struct ip)/sizeof(int); th=(struct tcphdr *)(pkt+1); switch(get_num(proto_name,proto_tab)) { case P_TCP: pkt->ip_p = IPPROTO_TCP; break; case P_UDP: pkt->ip_p = IPPROTO_UDP; break; default: fprintf(stderr,"%s: can check TCP/UDP packets\ only.\n",progname); exit(1); } if (frwl.fw_nsp!=1 || frwl.fw_ndp!=1) { fprintf(stderr,"%s: check needs one src/dst port.\n", progname); exit(1); } if (ntohl(frwl.fw_smsk.s_addr)!=ULONG_MAX || ntohl(frwl.fw_dmsk.s_addr)!=ULONG_MAX) { fprintf(stderr,"%s: can't check masked IP.\n",progname); exit(1); } pkt->ip_src.s_addr=frwl.fw_src.s_addr; pkt->ip_dst.s_addr=frwl.fw_dst.s_addr; th->th_sport=htons(frwl.fw_pts[0]); th->th_dport=htons(frwl.fw_pts[frwl.fw_nsp]); if (setsockopt(s,IPPROTO_IP,ctl,pkt,p_len)) printf("Packet DENYED.\n"); else printf("Packet ACCEPTED.\n"); exit(0); #endif } else { if (setsockopt(s,IPPROTO_IP,ctl,&frwl,sizeof(frwl))<0) { fprintf(stderr,"%s: setsockopt failed.\n",progname); exit(1); } } close(s); }