diff options
Diffstat (limited to '')
| -rw-r--r-- | src/obj/synproxy.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/src/obj/synproxy.c b/src/obj/synproxy.c new file mode 100644 index 0000000..baef5c2 --- /dev/null +++ b/src/obj/synproxy.c @@ -0,0 +1,147 @@ +#include <stdio.h> +#include <stdint.h> +#include <arpa/inet.h> +#include <errno.h> +#include <inttypes.h> + +#include <linux/netfilter/nf_tables.h> + +#include "internal.h" +#include <libmnl/libmnl.h> +#include <libnftnl/object.h> + +#include "obj.h" + +static int nftnl_obj_synproxy_set(struct nftnl_obj *e, uint16_t type, + const void *data, uint32_t data_len) +{ + struct nftnl_obj_synproxy *synproxy = nftnl_obj_data(e); + + switch (type) { + case NFTNL_OBJ_SYNPROXY_MSS: + synproxy->mss = *((uint16_t *)data); + break; + case NFTNL_OBJ_SYNPROXY_WSCALE: + synproxy->wscale = *((uint8_t *)data); + break; + case NFTNL_OBJ_SYNPROXY_FLAGS: + synproxy->flags = *((uint32_t *)data); + break; + default: + return -1; + } + return 0; +} + +static const void *nftnl_obj_synproxy_get(const struct nftnl_obj *e, + uint16_t type, uint32_t *data_len) +{ + struct nftnl_obj_synproxy *synproxy = nftnl_obj_data(e); + + switch (type) { + case NFTNL_OBJ_SYNPROXY_MSS: + *data_len = sizeof(synproxy->mss); + return &synproxy->mss; + case NFTNL_OBJ_SYNPROXY_WSCALE: + *data_len = sizeof(synproxy->wscale); + return &synproxy->wscale; + case NFTNL_OBJ_SYNPROXY_FLAGS: + *data_len = sizeof(synproxy->flags); + return &synproxy->flags; + } + return NULL; +} + +static int nftnl_obj_synproxy_cb(const struct nlattr *attr, void *data) +{ + int type = mnl_attr_get_type(attr); + const struct nlattr **tb = data; + + if (mnl_attr_type_valid(attr, NFTA_SYNPROXY_MAX) < 0) + return MNL_CB_OK; + + switch (type) { + case NFTA_SYNPROXY_MSS: + if (mnl_attr_validate(attr, MNL_TYPE_U16) < 0) + abi_breakage(); + break; + case NFTA_SYNPROXY_WSCALE: + if (mnl_attr_validate(attr, MNL_TYPE_U8) < 0) + abi_breakage(); + break; + case NFTA_SYNPROXY_FLAGS: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) + abi_breakage(); + break; + } + + tb[type] = attr; + return MNL_CB_OK; +} + +static void nftnl_obj_synproxy_build(struct nlmsghdr *nlh, + const struct nftnl_obj *e) +{ + struct nftnl_obj_synproxy *synproxy = nftnl_obj_data(e); + + if (e->flags & (1 << NFTNL_OBJ_SYNPROXY_MSS)) + mnl_attr_put_u16(nlh, NFTA_SYNPROXY_MSS, htons(synproxy->mss)); + if (e->flags & (1 << NFTNL_OBJ_SYNPROXY_WSCALE)) + mnl_attr_put_u8(nlh, NFTA_SYNPROXY_WSCALE, synproxy->wscale); + if (e->flags & (1 << NFTNL_OBJ_SYNPROXY_FLAGS)) + mnl_attr_put_u32(nlh, NFTA_SYNPROXY_FLAGS, + htonl(synproxy->flags)); +} + +static int nftnl_obj_synproxy_parse(struct nftnl_obj *e, struct nlattr *attr) +{ + struct nftnl_obj_synproxy *synproxy = nftnl_obj_data(e); + struct nlattr *tb[NFTA_SYNPROXY_MAX + 1] = {}; + + if (mnl_attr_parse_nested(attr, nftnl_obj_synproxy_cb, tb) < 0) + return -1; + + if (tb[NFTA_SYNPROXY_MSS]) { + synproxy->mss = ntohs(mnl_attr_get_u16(tb[NFTA_SYNPROXY_MSS])); + e->flags |= (1 << NFTNL_OBJ_SYNPROXY_MSS); + } + if (tb[NFTA_SYNPROXY_WSCALE]) { + synproxy->wscale = mnl_attr_get_u8(tb[NFTA_SYNPROXY_WSCALE]); + e->flags |= (1 << NFTNL_OBJ_SYNPROXY_WSCALE); + } + if (tb[NFTA_SYNPROXY_FLAGS]) { + synproxy->flags = ntohl(mnl_attr_get_u32(tb[NFTA_SYNPROXY_FLAGS])); + e->flags |= (1 << NFTNL_OBJ_SYNPROXY_FLAGS); + } + + return 0; +} + +static int nftnl_obj_synproxy_snprintf(char *buf, size_t len, + uint32_t flags, + const struct nftnl_obj *e) +{ + struct nftnl_obj_synproxy *synproxy = nftnl_obj_data(e); + int ret, offset = 0; + + if (e->flags & (1 << NFTNL_OBJ_SYNPROXY_MSS) && + e->flags & (1 << NFTNL_OBJ_SYNPROXY_WSCALE)) { + ret = snprintf(buf, len, "mss %u wscale %u ", synproxy->mss, + synproxy->wscale); + SNPRINTF_BUFFER_SIZE(ret, len, offset); + } + + return offset; +} + +struct obj_ops obj_ops_synproxy = { + .name = "synproxy", + .type = NFT_OBJECT_SYNPROXY, + .alloc_len = sizeof(struct nftnl_obj_synproxy), + .max_attr = NFTA_SYNPROXY_MAX, + .set = nftnl_obj_synproxy_set, + .get = nftnl_obj_synproxy_get, + .parse = nftnl_obj_synproxy_parse, + .build = nftnl_obj_synproxy_build, + .output = nftnl_obj_synproxy_snprintf, +}; |