| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <time.h> |
| |
| #include <libmnl/libmnl.h> |
| #include <libnetfilter_conntrack/libnetfilter_conntrack.h> |
| |
| struct callback_args { |
| struct mnl_socket *nl; |
| unsigned int seq; |
| int bit; |
| }; |
| |
| static void set_label(struct nf_conntrack *ct, struct callback_args *cbargs) |
| { |
| struct nfct_bitmask *b = (void *) nfct_get_attr(ct, ATTR_CONNLABELS); |
| int bit = cbargs->bit; |
| char buf[MNL_SOCKET_BUFFER_SIZE]; |
| struct nlmsghdr *nlh; |
| struct nfgenmsg *nfh; |
| |
| if (b) { |
| if (bit < 0) |
| b = nfct_bitmask_new(0); |
| else if (nfct_bitmask_test_bit(b, bit)) |
| return; |
| } else { |
| b = nfct_bitmask_new(0); |
| } |
| |
| if (!b) |
| return; |
| if (bit >= 0) |
| nfct_bitmask_set_bit(b, bit); |
| nfct_set_attr(ct, ATTR_CONNLABELS, b); |
| |
| if (bit >= 0) { |
| b = nfct_bitmask_new(bit); |
| if (b) { |
| nfct_bitmask_set_bit(b, bit); |
| nfct_set_attr(ct, ATTR_CONNLABELS_MASK, b); |
| } |
| } |
| |
| cbargs->seq++; |
| |
| nlh = mnl_nlmsg_put_header(buf); |
| nlh->nlmsg_type = (NFNL_SUBSYS_CTNETLINK << 8) | IPCTNL_MSG_CT_NEW; |
| nlh->nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE; |
| nlh->nlmsg_seq = cbargs->seq; |
| |
| nfh = mnl_nlmsg_put_extra_header(nlh, sizeof(struct nfgenmsg)); |
| nfh->nfgen_family = nfct_get_attr_u8(ct, ATTR_L3PROTO); |
| nfh->version = NFNETLINK_V0; |
| nfh->res_id = 0; |
| |
| nfct_nlmsg_build(nlh, ct); |
| |
| if (mnl_socket_sendto(cbargs->nl, nlh, nlh->nlmsg_len) < 0) |
| perror("mnl_socket_sendto"); |
| } |
| |
| static int data_cb(const struct nlmsghdr *nlh, void *data) |
| { |
| struct nf_conntrack *ct; |
| char buf[4096]; |
| |
| ct = nfct_new(); |
| if (ct == NULL) |
| return MNL_CB_OK; |
| |
| nfct_nlmsg_parse(nlh, ct); |
| |
| nfct_snprintf(buf, sizeof(buf), ct, NFCT_T_UNKNOWN, NFCT_O_DEFAULT, 0); |
| printf("%s\n", buf); |
| |
| set_label(ct, data); |
| |
| nfct_destroy(ct); |
| |
| return MNL_CB_OK; |
| } |
| |
| static void show_labels(struct nfct_labelmap *l) |
| { |
| unsigned int i = 0; |
| const char *name; |
| |
| if (l) { |
| fputs("usage: program label, configured labels are:\n", stderr); |
| while ((name = nfct_labelmap_get_name(l, i))) { |
| if (*name) |
| fprintf(stderr, "%s -> bit %d\n", name, i); |
| i++; |
| } |
| } else { |
| fputs("no labels configured, usage: program bit\n", stderr); |
| } |
| exit(1); |
| } |
| |
| static struct mnl_socket *sock_nl_create(void) |
| { |
| struct mnl_socket *nl; |
| |
| nl = mnl_socket_open(NETLINK_NETFILTER); |
| if (nl == NULL) { |
| perror("mnl_socket_open"); |
| exit(EXIT_FAILURE); |
| } |
| |
| if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) { |
| perror("mnl_socket_bind"); |
| exit(EXIT_FAILURE); |
| } |
| |
| return nl; |
| } |
| |
| int main(int argc, char *argv[]) |
| { |
| struct mnl_socket *nl; |
| struct nlmsghdr *nlh; |
| struct nfgenmsg *nfh; |
| char buf[MNL_SOCKET_BUFFER_SIZE]; |
| unsigned int seq, portid; |
| struct callback_args cbargs; |
| int ret; |
| struct nfct_labelmap *l = nfct_labelmap_new(NULL); |
| |
| if (argc < 2) |
| show_labels(l); |
| |
| cbargs.bit = l ? nfct_labelmap_get_bit(l, argv[1]) : -1; |
| |
| if (cbargs.bit < 0) { |
| cbargs.bit = atoi(argv[1]); |
| if (cbargs.bit == 0 && argv[1][0] != '0') |
| show_labels(l); |
| } |
| |
| if (cbargs.bit < 0) |
| puts("will clear all labels"); |
| else |
| printf("will set label bit %d\n", cbargs.bit); |
| |
| nl = sock_nl_create(); |
| portid = mnl_socket_get_portid(nl); |
| |
| nlh = mnl_nlmsg_put_header(buf); |
| nlh->nlmsg_type = (NFNL_SUBSYS_CTNETLINK << 8) | IPCTNL_MSG_CT_GET; |
| nlh->nlmsg_flags = NLM_F_REQUEST|NLM_F_DUMP; |
| nlh->nlmsg_seq = seq = time(NULL); |
| |
| nfh = mnl_nlmsg_put_extra_header(nlh, sizeof(struct nfgenmsg)); |
| nfh->nfgen_family = AF_UNSPEC; |
| nfh->version = NFNETLINK_V0; |
| nfh->res_id = 0; |
| |
| |
| ret = mnl_socket_sendto(nl, nlh, nlh->nlmsg_len); |
| if (ret == -1) { |
| perror("mnl_socket_sendto"); |
| exit(EXIT_FAILURE); |
| } |
| |
| ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); |
| |
| |
| cbargs.nl = sock_nl_create(); |
| cbargs.seq = seq; |
| |
| while (ret > 0) { |
| ret = mnl_cb_run(buf, ret, seq, portid, data_cb, &cbargs); |
| if (ret <= MNL_CB_STOP) |
| break; |
| ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); |
| } |
| if (ret == -1) { |
| perror("mnl_socket_recvfrom"); |
| exit(EXIT_FAILURE); |
| } |
| |
| if (l) |
| nfct_labelmap_destroy(l); |
| mnl_socket_close(nl); |
| |
| return 0; |
| } |