1 /* 2 * lib/netfilter/queue_msg.c Netfilter Queue Messages 3 * 4 * This library is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU Lesser General Public 6 * License as published by the Free Software Foundation version 2.1 7 * of the License. 8 * 9 * Copyright (c) 2007, 2008 Patrick McHardy <kaber (at) trash.net> 10 * Copyright (c) 2010 Karl Hiramoto <karl (at) hiramoto.org> 11 */ 12 13 /** 14 * @ingroup nfnl 15 * @defgroup queue Queue 16 * @brief 17 * @{ 18 */ 19 20 #include <sys/types.h> 21 #include <linux/netfilter/nfnetlink_queue.h> 22 23 #include <netlink-local.h> 24 #include <netlink/attr.h> 25 #include <netlink/netfilter/nfnl.h> 26 #include <netlink/netfilter/queue_msg.h> 27 28 static struct nl_cache_ops nfnl_queue_msg_ops; 29 30 #if __BYTE_ORDER == __BIG_ENDIAN 31 static uint64_t ntohll(uint64_t x) 32 { 33 return x; 34 } 35 #elif __BYTE_ORDER == __LITTLE_ENDIAN 36 static uint64_t ntohll(uint64_t x) 37 { 38 return __bswap_64(x); 39 } 40 #endif 41 42 static struct nla_policy queue_policy[NFQA_MAX+1] = { 43 [NFQA_PACKET_HDR] = { 44 .minlen = sizeof(struct nfqnl_msg_packet_hdr), 45 }, 46 [NFQA_VERDICT_HDR] = { 47 .minlen = sizeof(struct nfqnl_msg_verdict_hdr), 48 }, 49 [NFQA_MARK] = { .type = NLA_U32 }, 50 [NFQA_TIMESTAMP] = { 51 .minlen = sizeof(struct nfqnl_msg_packet_timestamp), 52 }, 53 [NFQA_IFINDEX_INDEV] = { .type = NLA_U32 }, 54 [NFQA_IFINDEX_OUTDEV] = { .type = NLA_U32 }, 55 [NFQA_IFINDEX_PHYSINDEV] = { .type = NLA_U32 }, 56 [NFQA_IFINDEX_PHYSOUTDEV] = { .type = NLA_U32 }, 57 [NFQA_HWADDR] = { 58 .minlen = sizeof(struct nfqnl_msg_packet_hw), 59 }, 60 }; 61 62 int nfnlmsg_queue_msg_parse(struct nlmsghdr *nlh, 63 struct nfnl_queue_msg **result) 64 { 65 struct nfnl_queue_msg *msg; 66 struct nlattr *tb[NFQA_MAX+1]; 67 struct nlattr *attr; 68 int err; 69 70 msg = nfnl_queue_msg_alloc(); 71 if (!msg) 72 return -NLE_NOMEM; 73 74 msg->ce_msgtype = nlh->nlmsg_type; 75 76 err = nlmsg_parse(nlh, sizeof(struct nfgenmsg), tb, NFQA_MAX, 77 queue_policy); 78 if (err < 0) 79 goto errout; 80 81 nfnl_queue_msg_set_group(msg, nfnlmsg_res_id(nlh)); 82 nfnl_queue_msg_set_family(msg, nfnlmsg_family(nlh)); 83 84 attr = tb[NFQA_PACKET_HDR]; 85 if (attr) { 86 struct nfqnl_msg_packet_hdr *hdr = nla_data(attr); 87 88 nfnl_queue_msg_set_packetid(msg, ntohl(hdr->packet_id)); 89 if (hdr->hw_protocol) 90 nfnl_queue_msg_set_hwproto(msg, hdr->hw_protocol); 91 nfnl_queue_msg_set_hook(msg, hdr->hook); 92 } 93 94 attr = tb[NFQA_MARK]; 95 if (attr) 96 nfnl_queue_msg_set_mark(msg, ntohl(nla_get_u32(attr))); 97 98 attr = tb[NFQA_TIMESTAMP]; 99 if (attr) { 100 struct nfqnl_msg_packet_timestamp *timestamp = nla_data(attr); 101 struct timeval tv; 102 103 tv.tv_sec = ntohll(timestamp->sec); 104 tv.tv_usec = ntohll(timestamp->usec); 105 nfnl_queue_msg_set_timestamp(msg, &tv); 106 } 107 108 attr = tb[NFQA_IFINDEX_INDEV]; 109 if (attr) 110 nfnl_queue_msg_set_indev(msg, ntohl(nla_get_u32(attr))); 111 112 attr = tb[NFQA_IFINDEX_OUTDEV]; 113 if (attr) 114 nfnl_queue_msg_set_outdev(msg, ntohl(nla_get_u32(attr))); 115 116 attr = tb[NFQA_IFINDEX_PHYSINDEV]; 117 if (attr) 118 nfnl_queue_msg_set_physindev(msg, ntohl(nla_get_u32(attr))); 119 120 attr = tb[NFQA_IFINDEX_PHYSOUTDEV]; 121 if (attr) 122 nfnl_queue_msg_set_physoutdev(msg, ntohl(nla_get_u32(attr))); 123 124 attr = tb[NFQA_HWADDR]; 125 if (attr) { 126 struct nfqnl_msg_packet_hw *hw = nla_data(attr); 127 128 nfnl_queue_msg_set_hwaddr(msg, hw->hw_addr, 129 ntohs(hw->hw_addrlen)); 130 } 131 132 attr = tb[NFQA_PAYLOAD]; 133 if (attr) { 134 err = nfnl_queue_msg_set_payload(msg, nla_data(attr), 135 nla_len(attr)); 136 if (err < 0) 137 goto errout; 138 } 139 140 *result = msg; 141 return 0; 142 143 errout: 144 nfnl_queue_msg_put(msg); 145 return err; 146 } 147 148 static int queue_msg_parser(struct nl_cache_ops *ops, struct sockaddr_nl *who, 149 struct nlmsghdr *nlh, struct nl_parser_param *pp) 150 { 151 struct nfnl_queue_msg *msg; 152 int err; 153 154 if ((err = nfnlmsg_queue_msg_parse(nlh, &msg)) < 0) 155 goto errout; 156 157 err = pp->pp_cb((struct nl_object *) msg, pp); 158 errout: 159 nfnl_queue_msg_put(msg); 160 return err; 161 } 162 163 /** @} */ 164 165 struct nl_msg *nfnl_queue_msg_build_verdict(const struct nfnl_queue_msg *msg) 166 { 167 struct nl_msg *nlmsg; 168 struct nfqnl_msg_verdict_hdr verdict; 169 170 nlmsg = nfnlmsg_alloc_simple(NFNL_SUBSYS_QUEUE, NFQNL_MSG_VERDICT, 0, 171 nfnl_queue_msg_get_family(msg), 172 nfnl_queue_msg_get_group(msg)); 173 if (nlmsg == NULL) 174 return NULL; 175 176 verdict.id = htonl(nfnl_queue_msg_get_packetid(msg)); 177 verdict.verdict = htonl(nfnl_queue_msg_get_verdict(msg)); 178 if (nla_put(nlmsg, NFQA_VERDICT_HDR, sizeof(verdict), &verdict) < 0) 179 goto nla_put_failure; 180 181 if (nfnl_queue_msg_test_mark(msg) && 182 nla_put_u32(nlmsg, NFQA_MARK, 183 ntohl(nfnl_queue_msg_get_mark(msg))) < 0) 184 goto nla_put_failure; 185 186 return nlmsg; 187 188 nla_put_failure: 189 nlmsg_free(nlmsg); 190 return NULL; 191 } 192 193 /** 194 * Send a message verdict/mark 195 * @arg nlh netlink messsage header 196 * @arg msg queue msg 197 * @return 0 on OK or error code 198 */ 199 int nfnl_queue_msg_send_verdict(struct nl_sock *nlh, 200 const struct nfnl_queue_msg *msg) 201 { 202 struct nl_msg *nlmsg; 203 int err; 204 205 nlmsg = nfnl_queue_msg_build_verdict(msg); 206 if (nlmsg == NULL) 207 return -NLE_NOMEM; 208 209 err = nl_send_auto_complete(nlh, nlmsg); 210 nlmsg_free(nlmsg); 211 if (err < 0) 212 return err; 213 return wait_for_ack(nlh); 214 } 215 216 /** 217 * Send a message verdict including the payload 218 * @arg nlh netlink messsage header 219 * @arg msg queue msg 220 * @arg payload_data packet payload data 221 * @arg payload_len payload length 222 * @return 0 on OK or error code 223 */ 224 int nfnl_queue_msg_send_verdict_payload(struct nl_sock *nlh, 225 const struct nfnl_queue_msg *msg, 226 const void *payload_data, unsigned payload_len) 227 { 228 struct nl_msg *nlmsg; 229 int err; 230 struct iovec iov[3]; 231 struct nlattr nla; 232 233 nlmsg = nfnl_queue_msg_build_verdict(msg); 234 if (nlmsg == NULL) 235 return -NLE_NOMEM; 236 237 memset(iov, 0, sizeof(iov)); 238 239 iov[0].iov_base = (void *) nlmsg_hdr(nlmsg); 240 iov[0].iov_len = nlmsg_hdr(nlmsg)->nlmsg_len; 241 242 nla.nla_type = NFQA_PAYLOAD; 243 nla.nla_len = payload_len + sizeof(nla); 244 nlmsg_hdr(nlmsg)->nlmsg_len += nla.nla_len; 245 246 iov[1].iov_base = (void *) &nla; 247 iov[1].iov_len = sizeof(nla); 248 249 iov[2].iov_base = (void *) payload_data; 250 iov[2].iov_len = NLA_ALIGN(payload_len); 251 252 nl_auto_complete(nlh, nlmsg); 253 err = nl_send_iovec(nlh, nlmsg, iov, 3); 254 255 nlmsg_free(nlmsg); 256 if (err < 0) 257 return err; 258 return wait_for_ack(nlh); 259 } 260 261 #define NFNLMSG_QUEUE_TYPE(type) NFNLMSG_TYPE(NFNL_SUBSYS_QUEUE, (type)) 262 static struct nl_cache_ops nfnl_queue_msg_ops = { 263 .co_name = "netfilter/queue_msg", 264 .co_hdrsize = NFNL_HDRLEN, 265 .co_msgtypes = { 266 { NFNLMSG_QUEUE_TYPE(NFQNL_MSG_PACKET), NL_ACT_NEW, "new" }, 267 END_OF_MSGTYPES_LIST, 268 }, 269 .co_protocol = NETLINK_NETFILTER, 270 .co_msg_parser = queue_msg_parser, 271 .co_obj_ops = &queue_msg_obj_ops, 272 }; 273 274 static void __init nfnl_msg_queue_init(void) 275 { 276 nl_cache_mngt_register(&nfnl_queue_msg_ops); 277 } 278 279 static void __exit nfnl_queue_msg_exit(void) 280 { 281 nl_cache_mngt_unregister(&nfnl_queue_msg_ops); 282 } 283 284 /** @} */ 285
