/* * iptunnel.c "ip tunnel" * * Licensed under the GPL v2 or later, see the file LICENSE in this tarball. * * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> * * * Changes: * * Rani Assaf <rani@magic.metawire.com> 980929: resolve addresses * Rani Assaf <rani@magic.metawire.com> 980930: do not allow key for ipip/sit * Phil Karn <karn@ka9q.ampr.org> 990408: "pmtudisc" flag */ #include <sys/socket.h> #include <sys/ioctl.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <arpa/inet.h> #include <netinet/ip.h> #include <netinet/in.h> #include <net/if.h> #include <net/if_arp.h> #include <asm/types.h> #ifndef __constant_htons #define __constant_htons htons #endif #include <linux/if_tunnel.h> #include "rt_names.h" #include "utils.h" #include "ip_common.h" #include "libbb.h" static int do_ioctl_get_ifindex(char *dev) { struct ifreq ifr; int fd; strcpy(ifr.ifr_name, dev); fd = socket(AF_INET, SOCK_DGRAM, 0); if (ioctl(fd, SIOCGIFINDEX, &ifr)) { bb_perror_msg("ioctl"); return 0; } close(fd); return ifr.ifr_ifindex; } static int do_ioctl_get_iftype(char *dev) { struct ifreq ifr; int fd; strcpy(ifr.ifr_name, dev); fd = socket(AF_INET, SOCK_DGRAM, 0); if (ioctl(fd, SIOCGIFHWADDR, &ifr)) { bb_perror_msg("ioctl"); return -1; } close(fd); return ifr.ifr_addr.sa_family; } static char *do_ioctl_get_ifname(int idx) { static struct ifreq ifr; int fd; ifr.ifr_ifindex = idx; fd = socket(AF_INET, SOCK_DGRAM, 0); if (ioctl(fd, SIOCGIFNAME, &ifr)) { bb_perror_msg("ioctl"); return NULL; } close(fd); return ifr.ifr_name; } static int do_get_ioctl(char *basedev, struct ip_tunnel_parm *p) { struct ifreq ifr; int fd; int err; strcpy(ifr.ifr_name, basedev); ifr.ifr_ifru.ifru_data = (void*)p; fd = socket(AF_INET, SOCK_DGRAM, 0); err = ioctl(fd, SIOCGETTUNNEL, &ifr); if (err) { bb_perror_msg("ioctl"); } close(fd); return err; } static int do_add_ioctl(int cmd, char *basedev, struct ip_tunnel_parm *p) { struct ifreq ifr; int fd; int err; if (cmd == SIOCCHGTUNNEL && p->name[0]) { strcpy(ifr.ifr_name, p->name); } else { strcpy(ifr.ifr_name, basedev); } ifr.ifr_ifru.ifru_data = (void*)p; fd = socket(AF_INET, SOCK_DGRAM, 0); err = ioctl(fd, cmd, &ifr); if (err) { bb_perror_msg("ioctl"); } close(fd); return err; } static int do_del_ioctl(char *basedev, struct ip_tunnel_parm *p) { struct ifreq ifr; int fd; int err; if (p->name[0]) { strcpy(ifr.ifr_name, p->name); } else { strcpy(ifr.ifr_name, basedev); } ifr.ifr_ifru.ifru_data = (void*)p; fd = socket(AF_INET, SOCK_DGRAM, 0); err = ioctl(fd, SIOCDELTUNNEL, &ifr); if (err) { bb_perror_msg("ioctl"); } close(fd); return err; } static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p) { int count = 0; char medium[IFNAMSIZ]; memset(p, 0, sizeof(*p)); memset(&medium, 0, sizeof(medium)); p->iph.version = 4; p->iph.ihl = 5; #ifndef IP_DF #define IP_DF 0x4000 /* Flag: "Don't Fragment" */ #endif p->iph.frag_off = htons(IP_DF); while (argc > 0) { if (strcmp(*argv, "mode") == 0) { NEXT_ARG(); if (strcmp(*argv, "ipip") == 0 || strcmp(*argv, "ip/ip") == 0) { if (p->iph.protocol && p->iph.protocol != IPPROTO_IPIP) { bb_error_msg("You managed to ask for more than one tunnel mode."); exit(-1); } p->iph.protocol = IPPROTO_IPIP; } else if (strcmp(*argv, "gre") == 0 || strcmp(*argv, "gre/ip") == 0) { if (p->iph.protocol && p->iph.protocol != IPPROTO_GRE) { bb_error_msg("You managed to ask for more than one tunnel mode."); exit(-1); } p->iph.protocol = IPPROTO_GRE; } else if (strcmp(*argv, "sit") == 0 || strcmp(*argv, "ipv6/ip") == 0) { if (p->iph.protocol && p->iph.protocol != IPPROTO_IPV6) { bb_error_msg("You managed to ask for more than one tunnel mode."); exit(-1); } p->iph.protocol = IPPROTO_IPV6; } else { bb_error_msg("Cannot guess tunnel mode."); exit(-1); } } else if (strcmp(*argv, "key") == 0) { unsigned uval; NEXT_ARG(); p->i_flags |= GRE_KEY; p->o_flags |= GRE_KEY; if (strchr(*argv, '.')) p->i_key = p->o_key = get_addr32(*argv); else { if (get_unsigned(&uval, *argv, 0)<0) { bb_error_msg("invalid value of \"key\""); exit(-1); } p->i_key = p->o_key = htonl(uval); } } else if (strcmp(*argv, "ikey") == 0) { unsigned uval; NEXT_ARG(); p->i_flags |= GRE_KEY; if (strchr(*argv, '.')) p->o_key = get_addr32(*argv); else { if (get_unsigned(&uval, *argv, 0)<0) { bb_error_msg("invalid value of \"ikey\""); exit(-1); } p->i_key = htonl(uval); } } else if (strcmp(*argv, "okey") == 0) { unsigned uval; NEXT_ARG(); p->o_flags |= GRE_KEY; if (strchr(*argv, '.')) p->o_key = get_addr32(*argv); else { if (get_unsigned(&uval, *argv, 0)<0) { bb_error_msg("invalid value of \"okey\""); exit(-1); } p->o_key = htonl(uval); } } else if (strcmp(*argv, "seq") == 0) { p->i_flags |= GRE_SEQ; p->o_flags |= GRE_SEQ; } else if (strcmp(*argv, "iseq") == 0) { p->i_flags |= GRE_SEQ; } else if (strcmp(*argv, "oseq") == 0) { p->o_flags |= GRE_SEQ; } else if (strcmp(*argv, "csum") == 0) { p->i_flags |= GRE_CSUM; p->o_flags |= GRE_CSUM; } else if (strcmp(*argv, "icsum") == 0) { p->i_flags |= GRE_CSUM; } else if (strcmp(*argv, "ocsum") == 0) { p->o_flags |= GRE_CSUM; } else if (strcmp(*argv, "nopmtudisc") == 0) { p->iph.frag_off = 0; } else if (strcmp(*argv, "pmtudisc") == 0) { p->iph.frag_off = htons(IP_DF); } else if (strcmp(*argv, "remote") == 0) { NEXT_ARG(); if (strcmp(*argv, "any")) p->iph.daddr = get_addr32(*argv); } else if (strcmp(*argv, "local") == 0) { NEXT_ARG(); if (strcmp(*argv, "any")) p->iph.saddr = get_addr32(*argv); } else if (strcmp(*argv, "dev") == 0) { NEXT_ARG(); strncpy(medium, *argv, IFNAMSIZ-1); } else if (strcmp(*argv, "ttl") == 0) { unsigned uval; NEXT_ARG(); if (strcmp(*argv, "inherit") != 0) { if (get_unsigned(&uval, *argv, 0)) invarg("invalid TTL\n", *argv); if (uval > 255) invarg("TTL must be <=255\n", *argv); p->iph.ttl = uval; } } else if (strcmp(*argv, "tos") == 0 || matches(*argv, "dsfield") == 0) { __u32 uval; NEXT_ARG(); if (strcmp(*argv, "inherit") != 0) { if (rtnl_dsfield_a2n(&uval, *argv)) invarg("bad TOS value", *argv); p->iph.tos = uval; } else p->iph.tos = 1; } else { if (strcmp(*argv, "name") == 0) { NEXT_ARG(); } if (p->name[0]) duparg2("name", *argv); strncpy(p->name, *argv, IFNAMSIZ); if (cmd == SIOCCHGTUNNEL && count == 0) { struct ip_tunnel_parm old_p; memset(&old_p, 0, sizeof(old_p)); if (do_get_ioctl(*argv, &old_p)) return -1; *p = old_p; } } count++; argc--; argv++; } if (p->iph.protocol == 0) { if (memcmp(p->name, "gre", 3) == 0) p->iph.protocol = IPPROTO_GRE; else if (memcmp(p->name, "ipip", 4) == 0) p->iph.protocol = IPPROTO_IPIP; else if (memcmp(p->name, "sit", 3) == 0) p->iph.protocol = IPPROTO_IPV6; } if (p->iph.protocol == IPPROTO_IPIP || p->iph.protocol == IPPROTO_IPV6) { if ((p->i_flags & GRE_KEY) || (p->o_flags & GRE_KEY)) { bb_error_msg("Keys are not allowed with ipip and sit."); return -1; } } if (medium[0]) { p->link = do_ioctl_get_ifindex(medium); if (p->link == 0) return -1; } if (p->i_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) { p->i_key = p->iph.daddr; p->i_flags |= GRE_KEY; } if (p->o_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) { p->o_key = p->iph.daddr; p->o_flags |= GRE_KEY; } if (IN_MULTICAST(ntohl(p->iph.daddr)) && !p->iph.saddr) { bb_error_msg("Broadcast tunnel requires a source address."); return -1; } return 0; } static int do_add(int cmd, int argc, char **argv) { struct ip_tunnel_parm p; if (parse_args(argc, argv, cmd, &p) < 0) return -1; if (p.iph.ttl && p.iph.frag_off == 0) { bb_error_msg("ttl != 0 and noptmudisc are incompatible"); return -1; } switch (p.iph.protocol) { case IPPROTO_IPIP: return do_add_ioctl(cmd, "tunl0", &p); case IPPROTO_GRE: return do_add_ioctl(cmd, "gre0", &p); case IPPROTO_IPV6: return do_add_ioctl(cmd, "sit0", &p); default: bb_error_msg("cannot determine tunnel mode (ipip, gre or sit)"); return -1; } return -1; } static int do_del(int argc, char **argv) { struct ip_tunnel_parm p; if (parse_args(argc, argv, SIOCDELTUNNEL, &p) < 0) return -1; switch (p.iph.protocol) { case IPPROTO_IPIP: return do_del_ioctl("tunl0", &p); case IPPROTO_GRE: return do_del_ioctl("gre0", &p); case IPPROTO_IPV6: return do_del_ioctl("sit0", &p); default: return do_del_ioctl(p.name, &p); } return -1; } static void print_tunnel(struct ip_tunnel_parm *p) { char s1[256]; char s2[256]; char s3[64]; char s4[64]; format_host(AF_INET, 4, &p->iph.daddr, s1, sizeof(s1)); format_host(AF_INET, 4, &p->iph.saddr, s2, sizeof(s2)); inet_ntop(AF_INET, &p->i_key, s3, sizeof(s3)); inet_ntop(AF_INET, &p->o_key, s4, sizeof(s4)); printf("%s: %s/ip remote %s local %s ", p->name, p->iph.protocol == IPPROTO_IPIP ? "ip" : (p->iph.protocol == IPPROTO_GRE ? "gre" : (p->iph.protocol == IPPROTO_IPV6 ? "ipv6" : "unknown")), p->iph.daddr ? s1 : "any", p->iph.saddr ? s2 : "any"); if (p->link) { char *n = do_ioctl_get_ifname(p->link); if (n) printf(" dev %s ", n); } if (p->iph.ttl) printf(" ttl %d ", p->iph.ttl); else printf(" ttl inherit "); if (p->iph.tos) { SPRINT_BUF(b1); printf(" tos"); if (p->iph.tos&1) printf(" inherit"); if (p->iph.tos&~1) printf("%c%s ", p->iph.tos&1 ? '/' : ' ', rtnl_dsfield_n2a(p->iph.tos&~1, b1, sizeof(b1))); } if (!(p->iph.frag_off&htons(IP_DF))) printf(" nopmtudisc"); if ((p->i_flags&GRE_KEY) && (p->o_flags&GRE_KEY) && p->o_key == p->i_key) printf(" key %s", s3); else if ((p->i_flags|p->o_flags)&GRE_KEY) { if (p->i_flags&GRE_KEY) printf(" ikey %s ", s3); if (p->o_flags&GRE_KEY) printf(" okey %s ", s4); } if (p->i_flags&GRE_SEQ) printf("%s Drop packets out of sequence.\n", _SL_); if (p->i_flags&GRE_CSUM) printf("%s Checksum in received packet is required.", _SL_); if (p->o_flags&GRE_SEQ) printf("%s Sequence packets on output.", _SL_); if (p->o_flags&GRE_CSUM) printf("%s Checksum output packets.", _SL_); } static int do_tunnels_list(struct ip_tunnel_parm *p) { char name[IFNAMSIZ]; unsigned long rx_bytes, rx_packets, rx_errs, rx_drops, rx_fifo, rx_frame, tx_bytes, tx_packets, tx_errs, tx_drops, tx_fifo, tx_colls, tx_carrier, rx_multi; int type; struct ip_tunnel_parm p1; char buf[512]; FILE *fp = fopen("/proc/net/dev", "r"); if (fp == NULL) { perror("fopen"); return -1; } fgets(buf, sizeof(buf), fp); fgets(buf, sizeof(buf), fp); while (fgets(buf, sizeof(buf), fp) != NULL) { char *ptr; buf[sizeof(buf) - 1] = 0; if ((ptr = strchr(buf, ':')) == NULL || (*ptr++ = 0, sscanf(buf, "%s", name) != 1)) { bb_error_msg("Wrong format of /proc/net/dev. Sorry."); return -1; } if (sscanf(ptr, "%lu%lu%lu%lu%lu%lu%lu%*d%lu%lu%lu%lu%lu%lu%lu", &rx_bytes, &rx_packets, &rx_errs, &rx_drops, &rx_fifo, &rx_frame, &rx_multi, &tx_bytes, &tx_packets, &tx_errs, &tx_drops, &tx_fifo, &tx_colls, &tx_carrier) != 14) continue; if (p->name[0] && strcmp(p->name, name)) continue; type = do_ioctl_get_iftype(name); if (type == -1) { bb_error_msg("Failed to get type of [%s]", name); continue; } if (type != ARPHRD_TUNNEL && type != ARPHRD_IPGRE && type != ARPHRD_SIT) continue; memset(&p1, 0, sizeof(p1)); if (do_get_ioctl(name, &p1)) continue; if ((p->link && p1.link != p->link) || (p->name[0] && strcmp(p1.name, p->name)) || (p->iph.daddr && p1.iph.daddr != p->iph.daddr) || (p->iph.saddr && p1.iph.saddr != p->iph.saddr) || (p->i_key && p1.i_key != p->i_key)) continue; print_tunnel(&p1); printf("\n"); } return 0; } static int do_show(int argc, char **argv) { int err; struct ip_tunnel_parm p; if (parse_args(argc, argv, SIOCGETTUNNEL, &p) < 0) return -1; switch (p.iph.protocol) { case IPPROTO_IPIP: err = do_get_ioctl(p.name[0] ? p.name : "tunl0", &p); break; case IPPROTO_GRE: err = do_get_ioctl(p.name[0] ? p.name : "gre0", &p); break; case IPPROTO_IPV6: err = do_get_ioctl(p.name[0] ? p.name : "sit0", &p); break; default: do_tunnels_list(&p); return 0; } if (err) return -1; print_tunnel(&p); printf("\n"); return 0; } int do_iptunnel(int argc, char **argv) { if (argc > 0) { if (matches(*argv, "add") == 0) return do_add(SIOCADDTUNNEL, argc-1, argv+1); if (matches(*argv, "change") == 0) return do_add(SIOCCHGTUNNEL, argc-1, argv+1); if (matches(*argv, "del") == 0) return do_del(argc-1, argv+1); if (matches(*argv, "show") == 0 || matches(*argv, "lst") == 0 || matches(*argv, "list") == 0) return do_show(argc-1, argv+1); } else return do_show(0, NULL); bb_error_msg("Command \"%s\" is unknown.", *argv); exit(-1); }