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-private/netlink.h> 24 #include <netlink/attr.h> 25 #include <netlink/netfilter/nfnl.h> 26 #include <netlink/netfilter/queue_msg.h> 27 #include <byteswap.h> 28 29 static struct nl_cache_ops nfnl_queue_msg_ops; 30 31 #if __BYTE_ORDER == __BIG_ENDIAN 32 static uint64_t ntohll(uint64_t x) 33 { 34 return x; 35 } 36 #elif __BYTE_ORDER == __LITTLE_ENDIAN 37 static uint64_t ntohll(uint64_t x) 38 { 39 return bswap_64(x); 40 } 41 #endif 42 43 static struct nla_policy queue_policy[NFQA_MAX+1] = { 44 [NFQA_PACKET_HDR] = { 45 .minlen = sizeof(struct nfqnl_msg_packet_hdr), 46 }, 47 [NFQA_VERDICT_HDR] = { 48 .minlen = sizeof(struct nfqnl_msg_verdict_hdr), 49 }, 50 [NFQA_MARK] = { .type = NLA_U32 }, 51 [NFQA_TIMESTAMP] = { 52 .minlen = sizeof(struct nfqnl_msg_packet_timestamp), 53 }, 54 [NFQA_IFINDEX_INDEV] = { .type = NLA_U32 }, 55 [NFQA_IFINDEX_OUTDEV] = { .type = NLA_U32 }, 56 [NFQA_IFINDEX_PHYSINDEV] = { .type = NLA_U32 }, 57 [NFQA_IFINDEX_PHYSOUTDEV] = { .type = NLA_U32 }, 58 [NFQA_HWADDR] = { 59 .minlen = sizeof(struct nfqnl_msg_packet_hw), 60 }, 61 }; 62 63 int nfnlmsg_queue_msg_parse(struct nlmsghdr *nlh, 64 struct nfnl_queue_msg **result) 65 { 66 struct nfnl_queue_msg *msg; 67 struct nlattr *tb[NFQA_MAX+1]; 68 struct nlattr *attr; 69 int err; 70 71 msg = nfnl_queue_msg_alloc(); 72 if (!msg) 73 return -NLE_NOMEM; 74 75 msg->ce_msgtype = nlh->nlmsg_type; 76 77 err = nlmsg_parse(nlh, sizeof(struct nfgenmsg), tb, NFQA_MAX, 78 queue_policy); 79 if (err < 0) 80 goto errout; 81 82 nfnl_queue_msg_set_group(msg, nfnlmsg_res_id(nlh)); 83 nfnl_queue_msg_set_family(msg, nfnlmsg_family(nlh)); 84 85 attr = tb[NFQA_PACKET_HDR]; 86 if (attr) { 87 struct nfqnl_msg_packet_hdr *hdr = nla_data(attr); 88 89 nfnl_queue_msg_set_packetid(msg, ntohl(hdr->packet_id)); 90 if (hdr->hw_protocol) 91 nfnl_queue_msg_set_hwproto(msg, hdr->hw_protocol); 92 nfnl_queue_msg_set_hook(msg, hdr->hook); 93 } 94 95 attr = tb[NFQA_MARK]; 96 if (attr) 97 nfnl_queue_msg_set_mark(msg, ntohl(nla_get_u32(attr))); 98 99 attr = tb[NFQA_TIMESTAMP]; 100 if (attr) { 101 struct nfqnl_msg_packet_timestamp *timestamp = nla_data(attr); 102 struct timeval tv; 103 104 tv.tv_sec = ntohll(timestamp->sec); 105 tv.tv_usec = ntohll(timestamp->usec); 106 nfnl_queue_msg_set_timestamp(msg, &tv); 107 } 108 109 attr = tb[NFQA_IFINDEX_INDEV]; 110 if (attr) 111 nfnl_queue_msg_set_indev(msg, ntohl(nla_get_u32(attr))); 112 113 attr = tb[NFQA_IFINDEX_OUTDEV]; 114 if (attr) 115 nfnl_queue_msg_set_outdev(msg, ntohl(nla_get_u32(attr))); 116 117 attr = tb[NFQA_IFINDEX_PHYSINDEV]; 118 if (attr) 119 nfnl_queue_msg_set_physindev(msg, ntohl(nla_get_u32(attr))); 120 121 attr = tb[NFQA_IFINDEX_PHYSOUTDEV]; 122 if (attr) 123 nfnl_queue_msg_set_physoutdev(msg, ntohl(nla_get_u32(attr))); 124 125 attr = tb[NFQA_HWADDR]; 126 if (attr) { 127 struct nfqnl_msg_packet_hw *hw = nla_data(attr); 128 129 nfnl_queue_msg_set_hwaddr(msg, hw->hw_addr, 130 ntohs(hw->hw_addrlen)); 131 } 132 133 attr = tb[NFQA_PAYLOAD]; 134 if (attr) { 135 err = nfnl_queue_msg_set_payload(msg, nla_data(attr), 136 nla_len(attr)); 137 if (err < 0) 138 goto errout; 139 } 140 141 *result = msg; 142 return 0; 143 144 errout: 145 nfnl_queue_msg_put(msg); 146 return err; 147 } 148 149 static int queue_msg_parser(struct nl_cache_ops *ops, struct sockaddr_nl *who, 150 struct nlmsghdr *nlh, struct nl_parser_param *pp) 151 { 152 struct nfnl_queue_msg *msg; 153 int err; 154 155 if ((err = nfnlmsg_queue_msg_parse(nlh, &msg)) < 0) 156 return err; 157 158 err = pp->pp_cb((struct nl_object *) msg, pp); 159 nfnl_queue_msg_put(msg); 160 return err; 161 } 162 163 /** @} */ 164 165 static struct nl_msg * 166 __nfnl_queue_msg_build_verdict(const struct nfnl_queue_msg *msg, 167 uint8_t type) 168 { 169 struct nl_msg *nlmsg; 170 struct nfqnl_msg_verdict_hdr verdict; 171 172 nlmsg = nfnlmsg_alloc_simple(NFNL_SUBSYS_QUEUE, type, 0, 173 nfnl_queue_msg_get_family(msg), 174 nfnl_queue_msg_get_group(msg)); 175 if (nlmsg == NULL) 176 return NULL; 177 178 verdict.id = htonl(nfnl_queue_msg_get_packetid(msg)); 179 verdict.verdict = htonl(nfnl_queue_msg_get_verdict(msg)); 180 if (nla_put(nlmsg, NFQA_VERDICT_HDR, sizeof(verdict), &verdict) < 0) 181 goto nla_put_failure; 182 183 if (nfnl_queue_msg_test_mark(msg) && 184 nla_put_u32(nlmsg, NFQA_MARK, 185 ntohl(nfnl_queue_msg_get_mark(msg))) < 0) 186 goto nla_put_failure; 187 188 return nlmsg; 189 190 nla_put_failure: 191 nlmsg_free(nlmsg); 192 return NULL; 193 } 194 195 struct nl_msg * 196 nfnl_queue_msg_build_verdict(const struct nfnl_queue_msg *msg) 197 { 198 return __nfnl_queue_msg_build_verdict(msg, NFQNL_MSG_VERDICT); 199 } 200 201 struct nl_msg * 202 nfnl_queue_msg_build_verdict_batch(const struct nfnl_queue_msg *msg) 203 { 204 return __nfnl_queue_msg_build_verdict(msg, NFQNL_MSG_VERDICT_BATCH); 205 } 206 207 /** 208 * Send a message verdict/mark 209 * @arg nlh netlink messsage header 210 * @arg msg queue msg 211 * @return 0 on OK or error code 212 */ 213 int nfnl_queue_msg_send_verdict(struct nl_sock *nlh, 214 const struct nfnl_queue_msg *msg) 215 { 216 struct nl_msg *nlmsg; 217 int err; 218 219 nlmsg = nfnl_queue_msg_build_verdict(msg); 220 if (nlmsg == NULL) 221 return -NLE_NOMEM; 222 223 err = nl_send_auto_complete(nlh, nlmsg); 224 nlmsg_free(nlmsg); 225 if (err < 0) 226 return err; 227 return wait_for_ack(nlh); 228 } 229 230 /** 231 * Send a message batched verdict/mark 232 * @arg nlh netlink messsage header 233 * @arg msg queue msg 234 * @return 0 on OK or error code 235 */ 236 int nfnl_queue_msg_send_verdict_batch(struct nl_sock *nlh, 237 const struct nfnl_queue_msg *msg) 238 { 239 struct nl_msg *nlmsg; 240 int err; 241 242 nlmsg = nfnl_queue_msg_build_verdict_batch(msg); 243 if (nlmsg == NULL) 244 return -NLE_NOMEM; 245 246 err = nl_send_auto_complete(nlh, nlmsg); 247 nlmsg_free(nlmsg); 248 if (err < 0) 249 return err; 250 return wait_for_ack(nlh); 251 } 252 253 /** 254 * Send a message verdict including the payload 255 * @arg nlh netlink messsage header 256 * @arg msg queue msg 257 * @arg payload_data packet payload data 258 * @arg payload_len payload length 259 * @return 0 on OK or error code 260 */ 261 int nfnl_queue_msg_send_verdict_payload(struct nl_sock *nlh, 262 const struct nfnl_queue_msg *msg, 263 const void *payload_data, unsigned payload_len) 264 { 265 struct nl_msg *nlmsg; 266 int err; 267 struct iovec iov[3]; 268 struct nlattr nla; 269 270 nlmsg = nfnl_queue_msg_build_verdict(msg); 271 if (nlmsg == NULL) 272 return -NLE_NOMEM; 273 274 memset(iov, 0, sizeof(iov)); 275 276 iov[0].iov_base = (void *) nlmsg_hdr(nlmsg); 277 iov[0].iov_len = nlmsg_hdr(nlmsg)->nlmsg_len; 278 279 nla.nla_type = NFQA_PAYLOAD; 280 nla.nla_len = payload_len + sizeof(nla); 281 nlmsg_hdr(nlmsg)->nlmsg_len += nla.nla_len; 282 283 iov[1].iov_base = (void *) &nla; 284 iov[1].iov_len = sizeof(nla); 285 286 iov[2].iov_base = (void *) payload_data; 287 iov[2].iov_len = NLA_ALIGN(payload_len); 288 289 nl_complete_msg(nlh, nlmsg); 290 err = nl_send_iovec(nlh, nlmsg, iov, 3); 291 292 nlmsg_free(nlmsg); 293 if (err < 0) 294 return err; 295 return wait_for_ack(nlh); 296 } 297 298 #define NFNLMSG_QUEUE_TYPE(type) NFNLMSG_TYPE(NFNL_SUBSYS_QUEUE, (type)) 299 static struct nl_cache_ops nfnl_queue_msg_ops = { 300 .co_name = "netfilter/queue_msg", 301 .co_hdrsize = NFNL_HDRLEN, 302 .co_msgtypes = { 303 { NFNLMSG_QUEUE_TYPE(NFQNL_MSG_PACKET), NL_ACT_NEW, "new" }, 304 END_OF_MSGTYPES_LIST, 305 }, 306 .co_protocol = NETLINK_NETFILTER, 307 .co_msg_parser = queue_msg_parser, 308 .co_obj_ops = &queue_msg_obj_ops, 309 }; 310 311 static void __init nfnl_msg_queue_init(void) 312 { 313 nl_cache_mngt_register(&nfnl_queue_msg_ops); 314 } 315 316 static void __exit nfnl_queue_msg_exit(void) 317 { 318 nl_cache_mngt_unregister(&nfnl_queue_msg_ops); 319 } 320 321 /** @} */ 322
