From 820dc0523e05c12810bb6bf4e56ce26e4c1948a2 Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Fri, 30 Sep 2022 00:38:43 +0200 Subject: [PATCH] net: netfilter: move bpf_ct_set_nat_info kfunc in nf_nat_bpf.c Remove circular dependency between nf_nat module and nf_conntrack one moving bpf_ct_set_nat_info kfunc in nf_nat_bpf.c Fixes: 0fabd2aa199f ("net: netfilter: add bpf_ct_set_nat_info kfunc helper") Suggested-by: Kumar Kartikeya Dwivedi Tested-by: Nathan Chancellor Tested-by: Yauheni Kaliuta Signed-off-by: Lorenzo Bianconi Acked-by: John Fastabend Link: https://lore.kernel.org/r/51a65513d2cda3eeb0754842e8025ab3966068d8.1664490511.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov --- include/net/netfilter/nf_conntrack_bpf.h | 19 ++++++++ net/netfilter/Makefile | 6 +++ net/netfilter/nf_conntrack_bpf.c | 50 -------------------- net/netfilter/nf_nat_bpf.c | 79 ++++++++++++++++++++++++++++++++ net/netfilter/nf_nat_core.c | 4 +- 5 files changed, 106 insertions(+), 52 deletions(-) create mode 100644 net/netfilter/nf_nat_bpf.c diff --git a/include/net/netfilter/nf_conntrack_bpf.h b/include/net/netfilter/nf_conntrack_bpf.h index c8b80ad..2d0da47 100644 --- a/include/net/netfilter/nf_conntrack_bpf.h +++ b/include/net/netfilter/nf_conntrack_bpf.h @@ -4,6 +4,11 @@ #define _NF_CONNTRACK_BPF_H #include +#include + +struct nf_conn___init { + struct nf_conn ct; +}; #if (IS_BUILTIN(CONFIG_NF_CONNTRACK) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) || \ (IS_MODULE(CONFIG_NF_CONNTRACK) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES)) @@ -24,4 +29,18 @@ static inline void cleanup_nf_conntrack_bpf(void) #endif +#if (IS_BUILTIN(CONFIG_NF_NAT) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) || \ + (IS_MODULE(CONFIG_NF_NAT) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES)) + +extern int register_nf_nat_bpf(void); + +#else + +static inline int register_nf_nat_bpf(void) +{ + return 0; +} + +#endif + #endif /* _NF_CONNTRACK_BPF_H */ diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile index 06df49e..0f060d1 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile @@ -60,6 +60,12 @@ obj-$(CONFIG_NF_NAT) += nf_nat.o nf_nat-$(CONFIG_NF_NAT_REDIRECT) += nf_nat_redirect.o nf_nat-$(CONFIG_NF_NAT_MASQUERADE) += nf_nat_masquerade.o +ifeq ($(CONFIG_NF_NAT),m) +nf_nat-$(CONFIG_DEBUG_INFO_BTF_MODULES) += nf_nat_bpf.o +else ifeq ($(CONFIG_NF_NAT),y) +nf_nat-$(CONFIG_DEBUG_INFO_BTF) += nf_nat_bpf.o +endif + # NAT helpers obj-$(CONFIG_NF_NAT_AMANDA) += nf_nat_amanda.o obj-$(CONFIG_NF_NAT_FTP) += nf_nat_ftp.o diff --git a/net/netfilter/nf_conntrack_bpf.c b/net/netfilter/nf_conntrack_bpf.c index 756ea818..8639e7e 100644 --- a/net/netfilter/nf_conntrack_bpf.c +++ b/net/netfilter/nf_conntrack_bpf.c @@ -14,10 +14,8 @@ #include #include #include -#include #include #include -#include /* bpf_ct_opts - Options for CT lookup helpers * @@ -239,10 +237,6 @@ __diag_push(); __diag_ignore_all("-Wmissing-prototypes", "Global functions as their definitions will be in nf_conntrack BTF"); -struct nf_conn___init { - struct nf_conn ct; -}; - /* bpf_xdp_ct_alloc - Allocate a new CT entry * * Parameters: @@ -476,49 +470,6 @@ int bpf_ct_change_status(struct nf_conn *nfct, u32 status) return nf_ct_change_status_common(nfct, status); } -/* bpf_ct_set_nat_info - Set source or destination nat address - * - * Set source or destination nat address of the newly allocated - * nf_conn before insertion. This must be invoked for referenced - * PTR_TO_BTF_ID to nf_conn___init. - * - * Parameters: - * @nfct - Pointer to referenced nf_conn object, obtained using - * bpf_xdp_ct_alloc or bpf_skb_ct_alloc. - * @addr - Nat source/destination address - * @port - Nat source/destination port. Non-positive values are - * interpreted as select a random port. - * @manip - NF_NAT_MANIP_SRC or NF_NAT_MANIP_DST - */ -int bpf_ct_set_nat_info(struct nf_conn___init *nfct, - union nf_inet_addr *addr, int port, - enum nf_nat_manip_type manip) -{ -#if ((IS_MODULE(CONFIG_NF_NAT) && IS_MODULE(CONFIG_NF_CONNTRACK)) || \ - IS_BUILTIN(CONFIG_NF_NAT)) - struct nf_conn *ct = (struct nf_conn *)nfct; - u16 proto = nf_ct_l3num(ct); - struct nf_nat_range2 range; - - if (proto != NFPROTO_IPV4 && proto != NFPROTO_IPV6) - return -EINVAL; - - memset(&range, 0, sizeof(struct nf_nat_range2)); - range.flags = NF_NAT_RANGE_MAP_IPS; - range.min_addr = *addr; - range.max_addr = range.min_addr; - if (port > 0) { - range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; - range.min_proto.all = cpu_to_be16(port); - range.max_proto.all = range.min_proto.all; - } - - return nf_nat_setup_info(ct, &range, manip) == NF_DROP ? -ENOMEM : 0; -#else - return -EOPNOTSUPP; -#endif -} - __diag_pop() BTF_SET8_START(nf_ct_kfunc_set) @@ -532,7 +483,6 @@ BTF_ID_FLAGS(func, bpf_ct_set_timeout, KF_TRUSTED_ARGS) BTF_ID_FLAGS(func, bpf_ct_change_timeout, KF_TRUSTED_ARGS) BTF_ID_FLAGS(func, bpf_ct_set_status, KF_TRUSTED_ARGS) BTF_ID_FLAGS(func, bpf_ct_change_status, KF_TRUSTED_ARGS) -BTF_ID_FLAGS(func, bpf_ct_set_nat_info, KF_TRUSTED_ARGS) BTF_SET8_END(nf_ct_kfunc_set) static const struct btf_kfunc_id_set nf_conntrack_kfunc_set = { diff --git a/net/netfilter/nf_nat_bpf.c b/net/netfilter/nf_nat_bpf.c new file mode 100644 index 0000000..0fa5a0b --- /dev/null +++ b/net/netfilter/nf_nat_bpf.c @@ -0,0 +1,79 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Unstable NAT Helpers for XDP and TC-BPF hook + * + * These are called from the XDP and SCHED_CLS BPF programs. Note that it is + * allowed to break compatibility for these functions since the interface they + * are exposed through to BPF programs is explicitly unstable. + */ + +#include +#include +#include +#include +#include + +__diag_push(); +__diag_ignore_all("-Wmissing-prototypes", + "Global functions as their definitions will be in nf_nat BTF"); + +/* bpf_ct_set_nat_info - Set source or destination nat address + * + * Set source or destination nat address of the newly allocated + * nf_conn before insertion. This must be invoked for referenced + * PTR_TO_BTF_ID to nf_conn___init. + * + * Parameters: + * @nfct - Pointer to referenced nf_conn object, obtained using + * bpf_xdp_ct_alloc or bpf_skb_ct_alloc. + * @addr - Nat source/destination address + * @port - Nat source/destination port. Non-positive values are + * interpreted as select a random port. + * @manip - NF_NAT_MANIP_SRC or NF_NAT_MANIP_DST + */ +int bpf_ct_set_nat_info(struct nf_conn___init *nfct, + union nf_inet_addr *addr, int port, + enum nf_nat_manip_type manip) +{ + struct nf_conn *ct = (struct nf_conn *)nfct; + u16 proto = nf_ct_l3num(ct); + struct nf_nat_range2 range; + + if (proto != NFPROTO_IPV4 && proto != NFPROTO_IPV6) + return -EINVAL; + + memset(&range, 0, sizeof(struct nf_nat_range2)); + range.flags = NF_NAT_RANGE_MAP_IPS; + range.min_addr = *addr; + range.max_addr = range.min_addr; + if (port > 0) { + range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; + range.min_proto.all = cpu_to_be16(port); + range.max_proto.all = range.min_proto.all; + } + + return nf_nat_setup_info(ct, &range, manip) == NF_DROP ? -ENOMEM : 0; +} + +__diag_pop() + +BTF_SET8_START(nf_nat_kfunc_set) +BTF_ID_FLAGS(func, bpf_ct_set_nat_info, KF_TRUSTED_ARGS) +BTF_SET8_END(nf_nat_kfunc_set) + +static const struct btf_kfunc_id_set nf_bpf_nat_kfunc_set = { + .owner = THIS_MODULE, + .set = &nf_nat_kfunc_set, +}; + +int register_nf_nat_bpf(void) +{ + int ret; + + ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, + &nf_bpf_nat_kfunc_set); + if (ret) + return ret; + + return register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, + &nf_bpf_nat_kfunc_set); +} diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c index 7981be5..d8e6380 100644 --- a/net/netfilter/nf_nat_core.c +++ b/net/netfilter/nf_nat_core.c @@ -16,7 +16,7 @@ #include #include -#include +#include #include #include #include @@ -1152,7 +1152,7 @@ static int __init nf_nat_init(void) WARN_ON(nf_nat_hook != NULL); RCU_INIT_POINTER(nf_nat_hook, &nat_hook); - return 0; + return register_nf_nat_bpf(); } static void __exit nf_nat_cleanup(void) -- 2.7.4