From e0dfd0df703f6eb5a3f2a73cd63914057ca4a4a0 Mon Sep 17 00:00:00 2001 From: "Jose M. Guisado Gomez" Date: Wed, 2 Sep 2020 11:12:40 +0200 Subject: object: add userdata and comment support This patch adds NFTNL_OBJ_USERDATA to support userdata for objects. Also adds NFTNL_UDATA_OBJ_COMMENT to support comments for objects, stored in userdata space. Bumps libnftnl.map to 15 as nftnl_obj_get_data needs to be exported to enable getting object attributes/data. Signed-off-by: Jose M. Guisado Gomez Signed-off-by: Pablo Neira Ayuso --- include/libnftnl/object.h | 1 + include/libnftnl/udata.h | 6 ++++++ include/linux/netfilter/nf_tables.h | 2 ++ include/obj.h | 5 +++++ src/libnftnl.map | 4 ++++ src/object.c | 26 ++++++++++++++++++++++++++ 6 files changed, 44 insertions(+) diff --git a/include/libnftnl/object.h b/include/libnftnl/object.h index 4c23774..9bd83a5 100644 --- a/include/libnftnl/object.h +++ b/include/libnftnl/object.h @@ -19,6 +19,7 @@ enum { NFTNL_OBJ_FAMILY, NFTNL_OBJ_USE, NFTNL_OBJ_HANDLE, + NFTNL_OBJ_USERDATA, NFTNL_OBJ_BASE = 16, __NFTNL_OBJ_MAX }; diff --git a/include/libnftnl/udata.h b/include/libnftnl/udata.h index ba6b3ab..2e38fcc 100644 --- a/include/libnftnl/udata.h +++ b/include/libnftnl/udata.h @@ -22,6 +22,12 @@ enum nftnl_udata_rule_types { }; #define NFTNL_UDATA_RULE_MAX (__NFTNL_UDATA_RULE_MAX - 1) +enum nftnl_udata_obj_types { + NFTNL_UDATA_OBJ_COMMENT, + __NFTNL_UDATA_OBJ_MAX +}; +#define NFTNL_UDATA_OBJ_MAX (__NFTNL_UDATA_OBJ_MAX - 1) + #define NFTNL_UDATA_COMMENT_MAXLEN 128 enum nftnl_udata_set_types { diff --git a/include/linux/netfilter/nf_tables.h b/include/linux/netfilter/nf_tables.h index d508154..8099777 100644 --- a/include/linux/netfilter/nf_tables.h +++ b/include/linux/netfilter/nf_tables.h @@ -1542,6 +1542,7 @@ enum nft_ct_expectation_attributes { * @NFTA_OBJ_DATA: stateful object data (NLA_NESTED) * @NFTA_OBJ_USE: number of references to this expression (NLA_U32) * @NFTA_OBJ_HANDLE: object handle (NLA_U64) + * @NFTA_OBJ_USERDATA: user data (NLA_BINARY) */ enum nft_object_attributes { NFTA_OBJ_UNSPEC, @@ -1552,6 +1553,7 @@ enum nft_object_attributes { NFTA_OBJ_USE, NFTA_OBJ_HANDLE, NFTA_OBJ_PAD, + NFTA_OBJ_USERDATA, __NFTA_OBJ_MAX }; #define NFTA_OBJ_MAX (__NFTA_OBJ_MAX - 1) diff --git a/include/obj.h b/include/obj.h index 10f806c..d9e856a 100644 --- a/include/obj.h +++ b/include/obj.h @@ -22,6 +22,11 @@ struct nftnl_obj { uint32_t flags; uint64_t handle; + struct { + void *data; + uint32_t len; + } user; + union { struct nftnl_obj_counter { uint64_t pkts; diff --git a/src/libnftnl.map b/src/libnftnl.map index 6042479..ceafa3f 100644 --- a/src/libnftnl.map +++ b/src/libnftnl.map @@ -368,3 +368,7 @@ LIBNFTNL_14 { nftnl_flowtable_set_array; nftnl_flowtable_get_array; } LIBNFTNL_13; + +LIBNFTNL_15 { + nftnl_obj_get_data; +} LIBNFTNL_14; diff --git a/src/object.c b/src/object.c index 4f58272..008bade 100644 --- a/src/object.c +++ b/src/object.c @@ -57,6 +57,8 @@ void nftnl_obj_free(const struct nftnl_obj *obj) xfree(obj->table); if (obj->flags & (1 << NFTNL_OBJ_NAME)) xfree(obj->name); + if (obj->flags & (1 << NFTNL_OBJ_USERDATA)) + xfree(obj->user.data); xfree(obj); } @@ -103,6 +105,16 @@ void nftnl_obj_set_data(struct nftnl_obj *obj, uint16_t attr, case NFTNL_OBJ_HANDLE: memcpy(&obj->handle, data, sizeof(obj->handle)); break; + case NFTNL_OBJ_USERDATA: + if (obj->flags & (1 << NFTNL_OBJ_USERDATA)) + xfree(obj->user.data); + + obj->user.data = malloc(data_len); + if (!obj->user.data) + return; + memcpy(obj->user.data, data, data_len); + obj->user.len = data_len; + break; default: if (obj->ops) obj->ops->set(obj, attr, data, data_len); @@ -174,6 +186,9 @@ const void *nftnl_obj_get_data(struct nftnl_obj *obj, uint16_t attr, case NFTNL_OBJ_HANDLE: *data_len = sizeof(uint64_t); return &obj->handle; + case NFTNL_OBJ_USERDATA: + *data_len = obj->user.len; + return obj->user.data; default: if (obj->ops) return obj->ops->get(obj, attr, data_len); @@ -235,6 +250,8 @@ void nftnl_obj_nlmsg_build_payload(struct nlmsghdr *nlh, mnl_attr_put_u32(nlh, NFTA_OBJ_TYPE, htonl(obj->ops->type)); if (obj->flags & (1 << NFTNL_OBJ_HANDLE)) mnl_attr_put_u64(nlh, NFTA_OBJ_HANDLE, htobe64(obj->handle)); + if (obj->flags & (1 << NFTNL_OBJ_USERDATA)) + mnl_attr_put(nlh, NFTA_OBJ_USERDATA, obj->user.len, obj->user.data); if (obj->ops) { struct nlattr *nest = mnl_attr_nest_start(nlh, NFTA_OBJ_DATA); @@ -269,6 +286,10 @@ static int nftnl_obj_parse_attr_cb(const struct nlattr *attr, void *data) if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) abi_breakage(); break; + case NFTA_OBJ_USERDATA: + if (mnl_attr_validate(attr, MNL_TYPE_BINARY) < 0) + abi_breakage(); + break; } tb[type] = attr; @@ -315,6 +336,11 @@ int nftnl_obj_nlmsg_parse(const struct nlmsghdr *nlh, struct nftnl_obj *obj) obj->handle = be64toh(mnl_attr_get_u64(tb[NFTA_OBJ_HANDLE])); obj->flags |= (1 << NFTNL_OBJ_HANDLE); } + if (tb[NFTA_OBJ_USERDATA]) { + nftnl_obj_set_data(obj, NFTNL_OBJ_USERDATA, + mnl_attr_get_payload(tb[NFTA_OBJ_USERDATA]), + mnl_attr_get_payload_len(tb[NFTA_OBJ_USERDATA])); + } obj->family = nfg->nfgen_family; obj->flags |= (1 << NFTNL_OBJ_FAMILY); -- cgit v1.2.3