/* vi: set sw=4 ts=4: */ /* * iprule.c "ip rule". * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> * * * Changes: * * Rani Assaf <rani@magic.metawire.com> 980929: resolve addresses * initially integrated into busybox by Bernhard Fischer */ #include <syslog.h> //#include <sys/socket.h> #include <netinet/in.h> #include <netinet/ip.h> #include <arpa/inet.h> #include "ip_common.h" /* #include "libbb.h" is inside */ #include "rt_names.h" #include "utils.h" /* static void usage(void) __attribute__((noreturn)); static void usage(void) { fprintf(stderr, "Usage: ip rule [ list | add | del ] SELECTOR ACTION\n"); fprintf(stderr, "SELECTOR := [ from PREFIX ] [ to PREFIX ] [ tos TOS ] [ fwmark FWMARK ]\n"); fprintf(stderr, " [ dev STRING ] [ pref NUMBER ]\n"); fprintf(stderr, "ACTION := [ table TABLE_ID ] [ nat ADDRESS ]\n"); fprintf(stderr, " [ prohibit | reject | unreachable ]\n"); fprintf(stderr, " [ realms [SRCREALM/]DSTREALM ]\n"); fprintf(stderr, "TABLE_ID := [ local | main | default | NUMBER ]\n"); exit(-1); } */ static int print_rule(struct sockaddr_nl *who ATTRIBUTE_UNUSED, struct nlmsghdr *n, void *arg) { FILE *fp = (FILE*)arg; struct rtmsg *r = NLMSG_DATA(n); int len = n->nlmsg_len; int host_len = -1; struct rtattr * tb[RTA_MAX+1]; char abuf[256]; SPRINT_BUF(b1); if (n->nlmsg_type != RTM_NEWRULE) return 0; len -= NLMSG_LENGTH(sizeof(*r)); if (len < 0) return -1; memset(tb, 0, sizeof(tb)); parse_rtattr(tb, RTA_MAX, RTM_RTA(r), len); if (r->rtm_family == AF_INET) host_len = 32; else if (r->rtm_family == AF_INET6) host_len = 128; /* else if (r->rtm_family == AF_DECnet) host_len = 16; else if (r->rtm_family == AF_IPX) host_len = 80; */ if (tb[RTA_PRIORITY]) fprintf(fp, "%u:\t", *(unsigned*)RTA_DATA(tb[RTA_PRIORITY])); else fprintf(fp, "0:\t"); fprintf(fp, "from "); if (tb[RTA_SRC]) { if (r->rtm_src_len != host_len) { fprintf(fp, "%s/%u", rt_addr_n2a(r->rtm_family, RTA_PAYLOAD(tb[RTA_SRC]), RTA_DATA(tb[RTA_SRC]), abuf, sizeof(abuf)), r->rtm_src_len ); } else { fprintf(fp, "%s", format_host(r->rtm_family, RTA_PAYLOAD(tb[RTA_SRC]), RTA_DATA(tb[RTA_SRC]), abuf, sizeof(abuf)) ); } } else if (r->rtm_src_len) { fprintf(fp, "0/%d", r->rtm_src_len); } else { fprintf(fp, "all"); } fprintf(fp, " "); if (tb[RTA_DST]) { if (r->rtm_dst_len != host_len) { fprintf(fp, "to %s/%u ", rt_addr_n2a(r->rtm_family, RTA_PAYLOAD(tb[RTA_DST]), RTA_DATA(tb[RTA_DST]), abuf, sizeof(abuf)), r->rtm_dst_len ); } else { fprintf(fp, "to %s ", format_host(r->rtm_family, RTA_PAYLOAD(tb[RTA_DST]), RTA_DATA(tb[RTA_DST]), abuf, sizeof(abuf))); } } else if (r->rtm_dst_len) { fprintf(fp, "to 0/%d ", r->rtm_dst_len); } if (r->rtm_tos) { fprintf(fp, "tos %s ", rtnl_dsfield_n2a(r->rtm_tos, b1, sizeof(b1))); } if (tb[RTA_PROTOINFO]) { fprintf(fp, "fwmark %#x ", *(uint32_t*)RTA_DATA(tb[RTA_PROTOINFO])); } if (tb[RTA_IIF]) { fprintf(fp, "iif %s ", (char*)RTA_DATA(tb[RTA_IIF])); } if (r->rtm_table) fprintf(fp, "lookup %s ", rtnl_rttable_n2a(r->rtm_table, b1, sizeof(b1))); if (tb[RTA_FLOW]) { uint32_t to = *(uint32_t*)RTA_DATA(tb[RTA_FLOW]); uint32_t from = to>>16; to &= 0xFFFF; if (from) { fprintf(fp, "realms %s/", rtnl_rtrealm_n2a(from, b1, sizeof(b1))); } fprintf(fp, "%s ", rtnl_rtrealm_n2a(to, b1, sizeof(b1))); } if (r->rtm_type == RTN_NAT) { if (tb[RTA_GATEWAY]) { fprintf(fp, "map-to %s ", format_host(r->rtm_family, RTA_PAYLOAD(tb[RTA_GATEWAY]), RTA_DATA(tb[RTA_GATEWAY]), abuf, sizeof(abuf))); } else fprintf(fp, "masquerade"); } else if (r->rtm_type != RTN_UNICAST) fprintf(fp, "%s", rtnl_rtntype_n2a(r->rtm_type, b1, sizeof(b1))); fputc('\n', fp); fflush(fp); return 0; } /* Return value becomes exitcode. It's okay to not return at all */ static int iprule_list(int argc, char **argv) { struct rtnl_handle rth; int af = preferred_family; if (af == AF_UNSPEC) af = AF_INET; if (argc > 0) { //bb_error_msg("\"rule show\" needs no arguments"); bb_warn_ignoring_args(argc); return -1; } xrtnl_open(&rth); xrtnl_wilddump_request(&rth, af, RTM_GETRULE); xrtnl_dump_filter(&rth, print_rule, stdout); return 0; } /* Return value becomes exitcode. It's okay to not return at all */ static int iprule_modify(int cmd, int argc, char **argv) { int table_ok = 0; struct rtnl_handle rth; struct { struct nlmsghdr n; struct rtmsg r; char buf[1024]; } req; memset(&req, 0, sizeof(req)); req.n.nlmsg_type = cmd; req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg)); req.n.nlmsg_flags = NLM_F_REQUEST; req.r.rtm_family = preferred_family; req.r.rtm_protocol = RTPROT_BOOT; req.r.rtm_scope = RT_SCOPE_UNIVERSE; req.r.rtm_table = 0; req.r.rtm_type = RTN_UNSPEC; if (cmd == RTM_NEWRULE) { req.n.nlmsg_flags |= NLM_F_CREATE|NLM_F_EXCL; req.r.rtm_type = RTN_UNICAST; } while (argc > 0) { if (strcmp(*argv, "from") == 0) { inet_prefix dst; NEXT_ARG(); get_prefix(&dst, *argv, req.r.rtm_family); req.r.rtm_src_len = dst.bitlen; addattr_l(&req.n, sizeof(req), RTA_SRC, &dst.data, dst.bytelen); } else if (strcmp(*argv, "to") == 0) { inet_prefix dst; NEXT_ARG(); get_prefix(&dst, *argv, req.r.rtm_family); req.r.rtm_dst_len = dst.bitlen; addattr_l(&req.n, sizeof(req), RTA_DST, &dst.data, dst.bytelen); } else if (matches(*argv, "preference") == 0 || matches(*argv, "order") == 0 || matches(*argv, "priority") == 0) { uint32_t pref; NEXT_ARG(); if (get_u32(&pref, *argv, 0)) invarg("preference value", *argv); addattr32(&req.n, sizeof(req), RTA_PRIORITY, pref); } else if (strcmp(*argv, "tos") == 0) { uint32_t tos; NEXT_ARG(); if (rtnl_dsfield_a2n(&tos, *argv)) invarg("TOS value", *argv); req.r.rtm_tos = tos; } else if (strcmp(*argv, "fwmark") == 0) { uint32_t fwmark; NEXT_ARG(); if (get_u32(&fwmark, *argv, 0)) invarg("fwmark value", *argv); addattr32(&req.n, sizeof(req), RTA_PROTOINFO, fwmark); } else if (matches(*argv, "realms") == 0) { uint32_t realm; NEXT_ARG(); if (get_rt_realms(&realm, *argv)) invarg("realms", *argv); addattr32(&req.n, sizeof(req), RTA_FLOW, realm); } else if (matches(*argv, "table") == 0 || strcmp(*argv, "lookup") == 0) { uint32_t tid; NEXT_ARG(); if (rtnl_rttable_a2n(&tid, *argv)) invarg("table ID", *argv); req.r.rtm_table = tid; table_ok = 1; } else if (strcmp(*argv, "dev") == 0 || strcmp(*argv, "iif") == 0) { NEXT_ARG(); addattr_l(&req.n, sizeof(req), RTA_IIF, *argv, strlen(*argv)+1); } else if (strcmp(*argv, "nat") == 0 || matches(*argv, "map-to") == 0) { NEXT_ARG(); addattr32(&req.n, sizeof(req), RTA_GATEWAY, get_addr32(*argv)); req.r.rtm_type = RTN_NAT; } else { int type; if (strcmp(*argv, "type") == 0) { NEXT_ARG(); } if (matches(*argv, "help") == 0) bb_show_usage(); if (rtnl_rtntype_a2n(&type, *argv)) // bogus-looking error message "invalid argument 'cannot parse rule type' to '<*argv>'" invarg("cannot parse rule type", *argv); req.r.rtm_type = type; } argc--; argv++; } if (req.r.rtm_family == AF_UNSPEC) req.r.rtm_family = AF_INET; if (!table_ok && cmd == RTM_NEWRULE) req.r.rtm_table = RT_TABLE_MAIN; xrtnl_open(&rth); if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0) return 2; return 0; } /* Return value becomes exitcode. It's okay to not return at all */ int do_iprule(int argc, char **argv) { static const char * const ip_rule_commands[] = {"add", "delete", "list", "show", 0}; int cmd = 2; /* list */ if (argc < 1) return iprule_list(0, NULL); if (*argv) cmd = index_in_substr_array(ip_rule_commands, *argv); switch (cmd) { case 0: /* add */ cmd = RTM_NEWRULE; break; case 1: /* delete */ cmd = RTM_DELRULE; break; case 2: /* list */ case 3: /* show */ return iprule_list(argc-1, argv+1); break; default: bb_error_msg_and_die("unknown command %s", *argv); } return iprule_modify(cmd, argc-1, argv+1); }