From 445a1e92c92d052007ab66b0a79d2bfa5683d493 Mon Sep 17 00:00:00 2001 From: "/C=DE/ST=Berlin/L=Berlin/O=Netfilter Project/OU=Development/CN=laforge/emailAddress=laforge@netfilter.org" Date: Wed, 26 Oct 2005 11:39:01 +0000 Subject: rename files correctly (Eric Leblond) --- src/libnetfilter_queue.c | 375 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 375 insertions(+) create mode 100644 src/libnetfilter_queue.c (limited to 'src/libnetfilter_queue.c') diff --git a/src/libnetfilter_queue.c b/src/libnetfilter_queue.c new file mode 100644 index 0000000..8e84c50 --- /dev/null +++ b/src/libnetfilter_queue.c @@ -0,0 +1,375 @@ +/* libnfqnetlink.c: generic library for access to nf_queue + * + * (C) 2005 by Harald Welte + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +struct nfqnl_handle +{ + struct nfnl_handle nfnlh; + struct nfqnl_q_handle *qh_list; +}; + +struct nfqnl_q_handle +{ + struct nfqnl_q_handle *next; + struct nfqnl_handle *h; + u_int16_t id; + + nfqnl_callback *cb; + void *data; +}; + + +int nfqnl_errno; + +/*********************************************************************** + * low level stuff + ***********************************************************************/ + +static void del_qh(struct nfqnl_q_handle *qh) +{ + struct nfqnl_q_handle *cur_qh, *prev_qh = NULL; + + for (cur_qh = qh->h->qh_list; cur_qh; cur_qh = cur_qh->next) { + if (cur_qh == qh) { + if (prev_qh) + prev_qh->next = qh->next; + else + qh->h->qh_list = qh->next; + return; + } + prev_qh = cur_qh; + } +} + +static void add_qh(struct nfqnl_q_handle *qh) +{ + qh->next = qh->h->qh_list; + qh->h->qh_list = qh; +} + +static struct nfqnl_q_handle *find_qh(struct nfqnl_handle *h, u_int16_t id) +{ + struct nfqnl_q_handle *qh; + + for (qh = h->qh_list; qh; qh = qh->next) { + if (qh->id == id) + return qh; + } + return NULL; +} + +/* build a NFQNL_MSG_CONFIG message */ + static int +__build_send_cfg_msg(struct nfqnl_handle *h, u_int8_t command, + u_int16_t queuenum, u_int16_t pf) +{ + char buf[NFNL_HEADER_LEN + +NFA_LENGTH(sizeof(struct nfqnl_msg_config_cmd))]; + struct nfqnl_msg_config_cmd cmd; + struct nlmsghdr *nmh = (struct nlmsghdr *) buf; + + nfnl_fill_hdr(&h->nfnlh, nmh, 0, AF_UNSPEC, queuenum, + NFQNL_MSG_CONFIG, NLM_F_REQUEST|NLM_F_ACK); + + cmd.command = command; + cmd.pf = htons(pf); + nfnl_addattr_l(nmh, sizeof(buf), NFQA_CFG_CMD, &cmd, sizeof(cmd)); + + return nfnl_talk(&h->nfnlh, nmh, 0, 0, NULL, NULL, NULL); +} + +static int __nfqnl_rcv_pkt(struct nlmsghdr *nlh, struct nfattr *nfa[], + void *data) +{ + struct nfgenmsg *nfmsg = NLMSG_DATA(nlh); + struct nfqnl_handle *h = data; + u_int16_t queue_num = ntohs(nfmsg->res_id); + struct nfqnl_q_handle *qh = find_qh(h, queue_num); + + if (!qh) + return -ENODEV; + + if (!qh->cb) + return -ENODEV; + + return qh->cb(qh, nfmsg, nfa, qh->data); +} + +static struct nfnl_callback pkt_cb = { + .call = &__nfqnl_rcv_pkt, + .attr_count = NFQA_MAX, +}; + +/* public interface */ + +struct nfnl_handle *nfqnl_nfnlh(struct nfqnl_handle *h) +{ + return &h->nfnlh; +} + +int nfqnl_fd(struct nfqnl_handle *h) +{ + return nfnl_fd(nfqnl_nfnlh(h)); +} + +struct nfqnl_handle *nfqnl_open(void) +{ + struct nfqnl_handle *h; + int err; + + h = malloc(sizeof(*h)); + if (!h) + return NULL; + + memset(h, 0, sizeof(*h)); + + err = nfnl_open(&h->nfnlh, NFNL_SUBSYS_QUEUE, NFQNL_MSG_MAX, 0); + if (err < 0) { + nfqnl_errno = err; + goto out_free; + } + + pkt_cb.data = h; + err = nfnl_callback_register(&h->nfnlh, NFQNL_MSG_PACKET, &pkt_cb); + if (err < 0) { + nfqnl_errno = err; + goto out_close; + } + + return h; +out_close: + nfnl_close(&h->nfnlh); +out_free: + free(h); + return NULL; +} + +int nfqnl_close(struct nfqnl_handle *h) +{ + int ret = nfnl_close(&h->nfnlh); + if (ret == 0) + free(h); + return ret; +} + +/* bind nf_queue from a specific protocol family */ +int nfqnl_bind_pf(struct nfqnl_handle *h, u_int16_t pf) +{ + return __build_send_cfg_msg(h, NFQNL_CFG_CMD_PF_BIND, 0, pf); +} + +/* unbind nf_queue from a specific protocol family */ +int nfqnl_unbind_pf(struct nfqnl_handle *h, u_int16_t pf) +{ + return __build_send_cfg_msg(h, NFQNL_CFG_CMD_PF_UNBIND, 0, pf); +} + +/* bind this socket to a specific queue number */ +struct nfqnl_q_handle *nfqnl_create_queue(struct nfqnl_handle *h, + u_int16_t num, + nfqnl_callback *cb, + void *data) +{ + int ret; + struct nfqnl_q_handle *qh; + + if (find_qh(h, num)) + return NULL; + + qh = malloc(sizeof(*qh)); + + memset(qh, 0, sizeof(*qh)); + qh->h = h; + qh->id = num; + qh->cb = cb; + qh->data = data; + + ret = __build_send_cfg_msg(h, NFQNL_CFG_CMD_BIND, num, 0); + if (ret < 0) { + nfqnl_errno = ret; + free(qh); + return NULL; + } + + add_qh(qh); + return qh; +} + +/* unbind this socket from a specific queue number */ +int nfqnl_destroy_queue(struct nfqnl_q_handle *qh) +{ + int ret = __build_send_cfg_msg(qh->h, NFQNL_CFG_CMD_UNBIND, qh->id, 0); + if (ret == 0) { + del_qh(qh); + free(qh); + } + + return ret; +} + +int nfqnl_handle_packet(struct nfqnl_handle *h, char *buf, int len) +{ + return nfnl_handle_packet(&h->nfnlh, buf, len); +} + +int nfqnl_set_mode(struct nfqnl_q_handle *qh, + u_int8_t mode, u_int32_t range) +{ + char buf[NFNL_HEADER_LEN + +NFA_LENGTH(sizeof(struct nfqnl_msg_config_params))]; + struct nfqnl_msg_config_params params; + struct nlmsghdr *nmh = (struct nlmsghdr *) buf; + + nfnl_fill_hdr(&qh->h->nfnlh, nmh, 0, AF_UNSPEC, qh->id, + NFQNL_MSG_CONFIG, NLM_F_REQUEST|NLM_F_ACK); + + params.copy_range = htonl(range); + params.copy_mode = mode; + nfnl_addattr_l(nmh, sizeof(buf), NFQA_CFG_PARAMS, ¶ms, + sizeof(params)); + + return nfnl_talk(&qh->h->nfnlh, nmh, 0, 0, NULL, NULL, NULL); +} + +static int __set_verdict(struct nfqnl_q_handle *qh, u_int32_t id, + u_int32_t verdict, u_int32_t mark, int set_mark, + u_int32_t data_len, unsigned char *data) +{ + struct nfqnl_msg_verdict_hdr vh; + char buf[NFNL_HEADER_LEN + +NFA_LENGTH(sizeof(mark)) + +NFA_LENGTH(sizeof(vh))]; + struct nlmsghdr *nmh = (struct nlmsghdr *) buf; + + struct iovec iov[3]; + int nvecs; + + memset(iov, 0, sizeof(iov)); + + vh.verdict = htonl(verdict); + vh.id = htonl(id); + + nfnl_fill_hdr(&qh->h->nfnlh, nmh, 0, AF_UNSPEC, qh->id, + NFQNL_MSG_VERDICT, NLM_F_REQUEST); + + /* add verdict header */ + nfnl_addattr_l(nmh, sizeof(buf), NFQA_VERDICT_HDR, &vh, sizeof(vh)); + + if (set_mark) + nfnl_addattr32(nmh, sizeof(buf), NFQA_MARK, mark); + + iov[0].iov_base = nmh; + iov[0].iov_len = NLMSG_TAIL(nmh) - (void *)nmh; + nvecs = 1; + + if (data_len) { + struct nfattr data_attr; + + nfnl_build_nfa_iovec(&iov[1], &data_attr, NFQA_PAYLOAD, + data_len, data); + nvecs += 2; + } + + return nfnl_sendiov(&qh->h->nfnlh, iov, nvecs, 0); +} + +int nfqnl_set_verdict(struct nfqnl_q_handle *qh, u_int32_t id, + u_int32_t verdict, u_int32_t data_len, + unsigned char *buf) +{ + return __set_verdict(qh, id, verdict, 0, 0, data_len, buf); +} + +int nfqnl_set_verdict_mark(struct nfqnl_q_handle *qh, u_int32_t id, + u_int32_t verdict, u_int32_t mark, + u_int32_t datalen, unsigned char *buf) +{ + return __set_verdict(qh, id, verdict, mark, 1, datalen, buf); +} + +/************************************************************* + * Message parsing functions + *************************************************************/ + +struct nfqnl_msg_packet_hdr *nfqnl_get_msg_packet_hdr(struct nfattr *nfa[]) +{ + return nfnl_get_pointer_to_data(nfa, NFQA_PACKET_HDR, + struct nfqnl_msg_packet_hdr); +} + +uint32_t nfqnl_get_nfmark(struct nfattr *nfa[]) +{ + return ntohl(nfnl_get_data(nfa, NFQA_MARK, u_int32_t)); +} + +struct nfqnl_msg_packet_timestamp *nfqnl_get_timestamp(struct nfattr *nfa[]) +{ + return nfnl_get_pointer_to_data(nfa, NFQA_TIMESTAMP, + struct nfqnl_msg_packet_timestamp); +} + +/* all nfqnl_get_*dev() functions return 0 if not set, since linux only allows + * ifindex >= 1, see net/core/dev.c:2600 (in 2.6.13.1) */ +u_int32_t nfqnl_get_indev(struct nfattr *nfa[]) +{ + return ntohl(nfnl_get_data(nfa, NFQA_IFINDEX_INDEV, u_int32_t)); +} + +u_int32_t nfqnl_get_physindev(struct nfattr *nfa[]) +{ + return ntohl(nfnl_get_data(nfa, NFQA_IFINDEX_PHYSINDEV, u_int32_t)); +} + +u_int32_t nfqnl_get_outdev(struct nfattr *nfa[]) +{ + return ntohl(nfnl_get_data(nfa, NFQA_IFINDEX_OUTDEV, u_int32_t)); +} + +u_int32_t nfqnl_get_physoutdev(struct nfattr *nfa[]) +{ + return ntohl(nfnl_get_data(nfa, NFQA_IFINDEX_PHYSOUTDEV, u_int32_t)); +} + +struct nfqnl_msg_packet_hw *nfqnl_get_packet_hw(struct nfattr *nfa[]) +{ + return nfnl_get_pointer_to_data(nfa, NFQA_HWADDR, + struct nfqnl_msg_packet_hw); +} + +int nfqnl_get_payload(struct nfattr *nfa[], char **data, + unsigned int *datalen) +{ + *data = nfnl_get_pointer_to_data(nfa, NFQA_PAYLOAD, char*); + if (*data) { + *datalen = NFA_PAYLOAD(nfa[NFQA_PAYLOAD-1]); + return 1; + } + return 0; +} -- cgit v1.2.3