diff options
Diffstat (limited to 'examples/nft-compat-get.c')
| -rw-r--r-- | examples/nft-compat-get.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/examples/nft-compat-get.c b/examples/nft-compat-get.c new file mode 100644 index 0000000..8f00cbf --- /dev/null +++ b/examples/nft-compat-get.c @@ -0,0 +1,140 @@ +/* + * (C) 2012 by Pablo Neira Ayuso <pablo@netfilter.org> + * + * 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. + * + * This software has been sponsored by Sophos Astaro <http://www.sophos.com> + */ + +#include <stdlib.h> +#include <time.h> +#include <string.h> +#include <netinet/in.h> + +#include <linux/netfilter/nfnetlink.h> +#include <linux/netfilter/nf_tables_compat.h> + +#include <libmnl/libmnl.h> + +static int data_attr_cb(const struct nlattr *attr, void *data) +{ + const struct nlattr **tb = data; + int type = mnl_attr_get_type(attr); + + if (mnl_attr_type_valid(attr, NFTA_COMPAT_MAX) < 0) + return MNL_CB_OK; + + switch(type) { + case NFTA_COMPAT_NAME: + if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0) { + perror("mnl_attr_validate"); + return MNL_CB_ERROR; + } + break; + case NFTA_COMPAT_REV: + case NFTA_COMPAT_TYPE: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) { + perror("mnl_attr_validate"); + return MNL_CB_ERROR; + } + break; + } + tb[type] = attr; + return MNL_CB_OK; +} + +static int cb(const struct nlmsghdr *nlh, void *data) +{ + struct nlattr *tb[NFTA_COMPAT_MAX+1] = {}; + struct nfgenmsg *nfg = mnl_nlmsg_get_payload(nlh); + + if (mnl_attr_parse(nlh, sizeof(*nfg), data_attr_cb, tb) < 0) + return MNL_CB_ERROR; + + if (tb[NFTA_COMPAT_NAME]) + printf("name=%s ", mnl_attr_get_str(tb[NFTA_COMPAT_NAME])); + if (tb[NFTA_COMPAT_REV]) + printf("rev=%d ", ntohl(mnl_attr_get_u32(tb[NFTA_COMPAT_REV]))); + if (tb[NFTA_COMPAT_TYPE]) + printf("type=%d ", ntohl(mnl_attr_get_u32(tb[NFTA_COMPAT_REV]))); + + printf("\n"); + + return MNL_CB_OK; +} + +int main(int argc, char *argv[]) +{ + struct mnl_socket *nl; + char buf[MNL_SOCKET_BUFFER_SIZE]; + struct nlmsghdr *nlh; + uint32_t portid, seq, rev, type; + int ret; + + if (argc != 4) { + fprintf(stderr, "Usage: %s <extension_name> <type> <rev>\n", + argv[0]); + return EXIT_FAILURE; + } + + if (strcmp(argv[2], "target") == 0) + type = 1; + else if (strcmp(argv[2], "match") == 0) + type = 0; + else { + fprintf(stderr, "type should be `target' or `match'\n"); + return EXIT_FAILURE; + } + rev = atoi(argv[3]); + + nlh = mnl_nlmsg_put_header(buf); + nlh->nlmsg_type = (NFNL_SUBSYS_NFT_COMPAT << 8) | NFNL_MSG_COMPAT_GET; + nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; + nlh->nlmsg_seq = seq = time(NULL); + + struct nfgenmsg *nfg = mnl_nlmsg_put_extra_header(nlh, sizeof(*nfg)); + nfg->nfgen_family = AF_INET; + nfg->version = NFNETLINK_V0; + nfg->res_id = 0; + + mnl_attr_put_strz(nlh, NFTA_COMPAT_NAME, argv[1]); + mnl_attr_put_u32(nlh, NFTA_COMPAT_REV, htonl(rev)); + mnl_attr_put_u32(nlh, NFTA_COMPAT_TYPE, htonl(type)); + + printf("requesting `%s' rev=%d type=%d\n", argv[1], rev, type); + + 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); + } + portid = mnl_socket_get_portid(nl); + + if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) { + perror("mnl_socket_send"); + exit(EXIT_FAILURE); + } + + ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); + while (ret > 0) { + ret = mnl_cb_run(buf, ret, seq, portid, cb, NULL); + if (ret <= 0) + break; + ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); + } + if (ret == -1) { + perror("error"); + exit(EXIT_FAILURE); + } + mnl_socket_close(nl); + + return EXIT_SUCCESS; +} |