diff options
Diffstat (limited to 'net/core/filter.c')
-rw-r--r-- | net/core/filter.c | 478 |
1 files changed, 466 insertions, 12 deletions
diff --git a/net/core/filter.c b/net/core/filter.c index 169974998c76..5912c738a7b2 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -55,6 +55,7 @@ #include <net/sock_reuseport.h> #include <net/busy_poll.h> #include <net/tcp.h> +#include <linux/bpf_trace.h> /** * sk_filter_trim_cap - run a packet through a socket filter @@ -513,14 +514,27 @@ do_pass: break; } - /* Convert JEQ into JNE when 'jump_true' is next insn. */ - if (fp->jt == 0 && BPF_OP(fp->code) == BPF_JEQ) { - insn->code = BPF_JMP | BPF_JNE | bpf_src; + /* Convert some jumps when 'jump_true' is next insn. */ + if (fp->jt == 0) { + switch (BPF_OP(fp->code)) { + case BPF_JEQ: + insn->code = BPF_JMP | BPF_JNE | bpf_src; + break; + case BPF_JGT: + insn->code = BPF_JMP | BPF_JLE | bpf_src; + break; + case BPF_JGE: + insn->code = BPF_JMP | BPF_JLT | bpf_src; + break; + default: + goto jmp_rest; + } + target = i + fp->jf + 1; BPF_EMIT_JMP; break; } - +jmp_rest: /* Other jumps are mapped into two insns: Jxx and JA. */ target = i + fp->jt + 1; insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src; @@ -1778,6 +1792,8 @@ static const struct bpf_func_proto bpf_clone_redirect_proto = { struct redirect_info { u32 ifindex; u32 flags; + struct bpf_map *map; + struct bpf_map *map_to_flush; }; static DEFINE_PER_CPU(struct redirect_info, redirect_info); @@ -1791,6 +1807,7 @@ BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags) ri->ifindex = ifindex; ri->flags = flags; + ri->map = NULL; return TC_ACT_REDIRECT; } @@ -1818,6 +1835,45 @@ static const struct bpf_func_proto bpf_redirect_proto = { .arg2_type = ARG_ANYTHING, }; +BPF_CALL_3(bpf_sk_redirect_map, struct bpf_map *, map, u32, key, u64, flags) +{ + struct redirect_info *ri = this_cpu_ptr(&redirect_info); + + if (unlikely(flags)) + return SK_ABORTED; + + ri->ifindex = key; + ri->flags = flags; + ri->map = map; + + return SK_REDIRECT; +} + +struct sock *do_sk_redirect_map(void) +{ + struct redirect_info *ri = this_cpu_ptr(&redirect_info); + struct sock *sk = NULL; + + if (ri->map) { + sk = __sock_map_lookup_elem(ri->map, ri->ifindex); + + ri->ifindex = 0; + ri->map = NULL; + /* we do not clear flags for future lookup */ + } + + return sk; +} + +static const struct bpf_func_proto bpf_sk_redirect_map_proto = { + .func = bpf_sk_redirect_map, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_CONST_MAP_PTR, + .arg2_type = ARG_ANYTHING, + .arg3_type = ARG_ANYTHING, +}; + BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb) { return task_get_classid(skb); @@ -2024,8 +2080,8 @@ static int bpf_skb_proto_4_to_6(struct sk_buff *skb) return ret; if (skb_is_gso(skb)) { - /* SKB_GSO_UDP stays as is. SKB_GSO_TCPV4 needs to - * be changed into SKB_GSO_TCPV6. + /* SKB_GSO_TCPV4 needs to be changed into + * SKB_GSO_TCPV6. */ if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) { skb_shinfo(skb)->gso_type &= ~SKB_GSO_TCPV4; @@ -2060,8 +2116,8 @@ static int bpf_skb_proto_6_to_4(struct sk_buff *skb) return ret; if (skb_is_gso(skb)) { - /* SKB_GSO_UDP stays as is. SKB_GSO_TCPV6 needs to - * be changed into SKB_GSO_TCPV4. + /* SKB_GSO_TCPV6 needs to be changed into + * SKB_GSO_TCPV4. */ if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) { skb_shinfo(skb)->gso_type &= ~SKB_GSO_TCPV6; @@ -2412,6 +2468,180 @@ static const struct bpf_func_proto bpf_xdp_adjust_head_proto = { .arg2_type = ARG_ANYTHING, }; +static int __bpf_tx_xdp(struct net_device *dev, + struct bpf_map *map, + struct xdp_buff *xdp, + u32 index) +{ + int err; + + if (!dev->netdev_ops->ndo_xdp_xmit) { + return -EOPNOTSUPP; + } + + err = dev->netdev_ops->ndo_xdp_xmit(dev, xdp); + if (err) + return err; + if (map) + __dev_map_insert_ctx(map, index); + else + dev->netdev_ops->ndo_xdp_flush(dev); + return 0; +} + +void xdp_do_flush_map(void) +{ + struct redirect_info *ri = this_cpu_ptr(&redirect_info); + struct bpf_map *map = ri->map_to_flush; + + ri->map_to_flush = NULL; + if (map) + __dev_map_flush(map); +} +EXPORT_SYMBOL_GPL(xdp_do_flush_map); + +static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp, + struct bpf_prog *xdp_prog) +{ + struct redirect_info *ri = this_cpu_ptr(&redirect_info); + struct bpf_map *map = ri->map; + u32 index = ri->ifindex; + struct net_device *fwd; + int err; + + ri->ifindex = 0; + ri->map = NULL; + + fwd = __dev_map_lookup_elem(map, index); + if (!fwd) { + err = -EINVAL; + goto err; + } + if (ri->map_to_flush && ri->map_to_flush != map) + xdp_do_flush_map(); + + err = __bpf_tx_xdp(fwd, map, xdp, index); + if (unlikely(err)) + goto err; + + ri->map_to_flush = map; + _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index); + return 0; +err: + _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err); + return err; +} + +int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, + struct bpf_prog *xdp_prog) +{ + struct redirect_info *ri = this_cpu_ptr(&redirect_info); + struct net_device *fwd; + u32 index = ri->ifindex; + int err; + + if (ri->map) + return xdp_do_redirect_map(dev, xdp, xdp_prog); + + fwd = dev_get_by_index_rcu(dev_net(dev), index); + ri->ifindex = 0; + if (unlikely(!fwd)) { + err = -EINVAL; + goto err; + } + + err = __bpf_tx_xdp(fwd, NULL, xdp, 0); + if (unlikely(err)) + goto err; + + _trace_xdp_redirect(dev, xdp_prog, index); + return 0; +err: + _trace_xdp_redirect_err(dev, xdp_prog, index, err); + return err; +} +EXPORT_SYMBOL_GPL(xdp_do_redirect); + +int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb, + struct bpf_prog *xdp_prog) +{ + struct redirect_info *ri = this_cpu_ptr(&redirect_info); + u32 index = ri->ifindex; + struct net_device *fwd; + unsigned int len; + int err = 0; + + fwd = dev_get_by_index_rcu(dev_net(dev), index); + ri->ifindex = 0; + if (unlikely(!fwd)) { + err = -EINVAL; + goto err; + } + + if (unlikely(!(fwd->flags & IFF_UP))) { + err = -ENETDOWN; + goto err; + } + + len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN; + if (skb->len > len) { + err = -EMSGSIZE; + goto err; + } + + skb->dev = fwd; + _trace_xdp_redirect(dev, xdp_prog, index); + return 0; +err: + _trace_xdp_redirect_err(dev, xdp_prog, index, err); + return err; +} +EXPORT_SYMBOL_GPL(xdp_do_generic_redirect); + +BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags) +{ + struct redirect_info *ri = this_cpu_ptr(&redirect_info); + + if (unlikely(flags)) + return XDP_ABORTED; + + ri->ifindex = ifindex; + ri->flags = flags; + + return XDP_REDIRECT; +} + +static const struct bpf_func_proto bpf_xdp_redirect_proto = { + .func = bpf_xdp_redirect, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_ANYTHING, + .arg2_type = ARG_ANYTHING, +}; + +BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, u64, flags) +{ + struct redirect_info *ri = this_cpu_ptr(&redirect_info); + + if (unlikely(flags)) + return XDP_ABORTED; + + ri->ifindex = ifindex; + ri->flags = flags; + ri->map = map; + + return XDP_REDIRECT; +} + +static const struct bpf_func_proto bpf_xdp_redirect_map_proto = { + .func = bpf_xdp_redirect_map, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_CONST_MAP_PTR, + .arg2_type = ARG_ANYTHING, + .arg3_type = ARG_ANYTHING, +}; + bool bpf_helper_changes_pkt_data(void *func) { if (func == bpf_skb_vlan_push || @@ -2916,6 +3146,20 @@ bpf_base_func_proto(enum bpf_func_id func_id) } static const struct bpf_func_proto * +sock_filter_func_proto(enum bpf_func_id func_id) +{ + switch (func_id) { + /* inet and inet6 sockets are created in a process + * context so there is always a valid uid/gid + */ + case BPF_FUNC_get_current_uid_gid: + return &bpf_get_current_uid_gid_proto; + default: + return bpf_base_func_proto(func_id); + } +} + +static const struct bpf_func_proto * sk_filter_func_proto(enum bpf_func_id func_id) { switch (func_id) { @@ -3007,6 +3251,10 @@ xdp_func_proto(enum bpf_func_id func_id) return &bpf_get_smp_processor_id_proto; case BPF_FUNC_xdp_adjust_head: return &bpf_xdp_adjust_head_proto; + case BPF_FUNC_redirect: + return &bpf_xdp_redirect_proto; + case BPF_FUNC_redirect_map: + return &bpf_xdp_redirect_map_proto; default: return bpf_base_func_proto(func_id); } @@ -3045,6 +3293,32 @@ static const struct bpf_func_proto * switch (func_id) { case BPF_FUNC_setsockopt: return &bpf_setsockopt_proto; + case BPF_FUNC_sock_map_update: + return &bpf_sock_map_update_proto; + default: + return bpf_base_func_proto(func_id); + } +} + +static const struct bpf_func_proto *sk_skb_func_proto(enum bpf_func_id func_id) +{ + switch (func_id) { + case BPF_FUNC_skb_store_bytes: + return &bpf_skb_store_bytes_proto; + case BPF_FUNC_skb_load_bytes: + return &bpf_skb_load_bytes_proto; + case BPF_FUNC_skb_pull_data: + return &bpf_skb_pull_data_proto; + case BPF_FUNC_skb_change_tail: + return &bpf_skb_change_tail_proto; + case BPF_FUNC_skb_change_head: + return &bpf_skb_change_head_proto; + case BPF_FUNC_get_socket_cookie: + return &bpf_get_socket_cookie_proto; + case BPF_FUNC_get_socket_uid: + return &bpf_get_socket_uid_proto; + case BPF_FUNC_sk_redirect_map: + return &bpf_sk_redirect_map_proto; default: return bpf_base_func_proto(func_id); } @@ -3102,6 +3376,10 @@ static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type if (off + size > offsetofend(struct __sk_buff, cb[4])) return false; break; + case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]): + case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]): + case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4): + case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4): case bpf_ctx_range(struct __sk_buff, data): case bpf_ctx_range(struct __sk_buff, data_end): if (size != size_default) @@ -3130,6 +3408,7 @@ static bool sk_filter_is_valid_access(int off, int size, case bpf_ctx_range(struct __sk_buff, tc_classid): case bpf_ctx_range(struct __sk_buff, data): case bpf_ctx_range(struct __sk_buff, data_end): + case bpf_ctx_range_till(struct __sk_buff, family, local_port): return false; } @@ -3151,6 +3430,7 @@ static bool lwt_is_valid_access(int off, int size, { switch (off) { case bpf_ctx_range(struct __sk_buff, tc_classid): + case bpf_ctx_range_till(struct __sk_buff, family, local_port): return false; } @@ -3184,6 +3464,8 @@ static bool sock_filter_is_valid_access(int off, int size, if (type == BPF_WRITE) { switch (off) { case offsetof(struct bpf_sock, bound_dev_if): + case offsetof(struct bpf_sock, mark): + case offsetof(struct bpf_sock, priority): break; default: return false; @@ -3201,8 +3483,8 @@ static bool sock_filter_is_valid_access(int off, int size, return true; } -static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write, - const struct bpf_prog *prog) +static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write, + const struct bpf_prog *prog, int drop_verdict) { struct bpf_insn *insn = insn_buf; @@ -3229,7 +3511,7 @@ static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write, * return TC_ACT_SHOT; */ *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2); - *insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, TC_ACT_SHOT); + *insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict); *insn++ = BPF_EXIT_INSN(); /* restore: */ @@ -3240,6 +3522,12 @@ static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write, return insn - insn_buf; } +static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write, + const struct bpf_prog *prog) +{ + return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT); +} + static bool tc_cls_act_is_valid_access(int off, int size, enum bpf_access_type type, struct bpf_insn_access_aux *info) @@ -3264,6 +3552,8 @@ static bool tc_cls_act_is_valid_access(int off, int size, case bpf_ctx_range(struct __sk_buff, data_end): info->reg_type = PTR_TO_PACKET_END; break; + case bpf_ctx_range_till(struct __sk_buff, family, local_port): + return false; } return bpf_skb_is_valid_access(off, size, type, info); @@ -3336,6 +3626,41 @@ static bool sock_ops_is_valid_access(int off, int size, return __is_valid_sock_ops_access(off, size); } +static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write, + const struct bpf_prog *prog) +{ + return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP); +} + +static bool sk_skb_is_valid_access(int off, int size, + enum bpf_access_type type, + struct bpf_insn_access_aux *info) +{ + if (type == BPF_WRITE) { + switch (off) { + case bpf_ctx_range(struct __sk_buff, mark): + case bpf_ctx_range(struct __sk_buff, tc_index): + case bpf_ctx_range(struct __sk_buff, priority): + break; + default: + return false; + } + } + + switch (off) { + case bpf_ctx_range(struct __sk_buff, tc_classid): + return false; + case bpf_ctx_range(struct __sk_buff, data): + info->reg_type = PTR_TO_PACKET; + break; + case bpf_ctx_range(struct __sk_buff, data_end): + info->reg_type = PTR_TO_PACKET_END; + break; + } + + return bpf_skb_is_valid_access(off, size, type, info); +} + static u32 bpf_convert_ctx_access(enum bpf_access_type type, const struct bpf_insn *si, struct bpf_insn *insn_buf, @@ -3521,6 +3846,106 @@ static u32 bpf_convert_ctx_access(enum bpf_access_type type, *insn++ = BPF_MOV64_IMM(si->dst_reg, 0); #endif break; + case offsetof(struct __sk_buff, family): + BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2); + + *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), + si->dst_reg, si->src_reg, + offsetof(struct sk_buff, sk)); + *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, + bpf_target_off(struct sock_common, + skc_family, + 2, target_size)); + break; + case offsetof(struct __sk_buff, remote_ip4): + BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4); + + *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), + si->dst_reg, si->src_reg, + offsetof(struct sk_buff, sk)); + *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, + bpf_target_off(struct sock_common, + skc_daddr, + 4, target_size)); + break; + case offsetof(struct __sk_buff, local_ip4): + BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, + skc_rcv_saddr) != 4); + + *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), + si->dst_reg, si->src_reg, + offsetof(struct sk_buff, sk)); + *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, + bpf_target_off(struct sock_common, + skc_rcv_saddr, + 4, target_size)); + break; + case offsetof(struct __sk_buff, remote_ip6[0]) ... + offsetof(struct __sk_buff, remote_ip6[3]): +#if IS_ENABLED(CONFIG_IPV6) + BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, + skc_v6_daddr.s6_addr32[0]) != 4); + + off = si->off; + off -= offsetof(struct __sk_buff, remote_ip6[0]); + + *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), + si->dst_reg, si->src_reg, + offsetof(struct sk_buff, sk)); + *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, + offsetof(struct sock_common, + skc_v6_daddr.s6_addr32[0]) + + off); +#else + *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); +#endif + break; + case offsetof(struct __sk_buff, local_ip6[0]) ... + offsetof(struct __sk_buff, local_ip6[3]): +#if IS_ENABLED(CONFIG_IPV6) + BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, + skc_v6_rcv_saddr.s6_addr32[0]) != 4); + + off = si->off; + off -= offsetof(struct __sk_buff, local_ip6[0]); + + *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), + si->dst_reg, si->src_reg, + offsetof(struct sk_buff, sk)); + *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, + offsetof(struct sock_common, + skc_v6_rcv_saddr.s6_addr32[0]) + + off); +#else + *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); +#endif + break; + + case offsetof(struct __sk_buff, remote_port): + BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2); + + *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), + si->dst_reg, si->src_reg, + offsetof(struct sk_buff, sk)); + *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, + bpf_target_off(struct sock_common, + skc_dport, + 2, target_size)); +#ifndef __BIG_ENDIAN_BITFIELD + *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16); +#endif + break; + + case offsetof(struct __sk_buff, local_port): + BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2); + + *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), + si->dst_reg, si->src_reg, + offsetof(struct sk_buff, sk)); + *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, + bpf_target_off(struct sock_common, + skc_num, 2, target_size)); + break; } return insn - insn_buf; @@ -3545,6 +3970,28 @@ static u32 sock_filter_convert_ctx_access(enum bpf_access_type type, offsetof(struct sock, sk_bound_dev_if)); break; + case offsetof(struct bpf_sock, mark): + BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_mark) != 4); + + if (type == BPF_WRITE) + *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, + offsetof(struct sock, sk_mark)); + else + *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, + offsetof(struct sock, sk_mark)); + break; + + case offsetof(struct bpf_sock, priority): + BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_priority) != 4); + + if (type == BPF_WRITE) + *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, + offsetof(struct sock, sk_priority)); + else + *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, + offsetof(struct sock, sk_priority)); + break; + case offsetof(struct bpf_sock, family): BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_family) != 2); @@ -3794,7 +4241,7 @@ const struct bpf_verifier_ops lwt_xmit_prog_ops = { }; const struct bpf_verifier_ops cg_sock_prog_ops = { - .get_func_proto = bpf_base_func_proto, + .get_func_proto = sock_filter_func_proto, .is_valid_access = sock_filter_is_valid_access, .convert_ctx_access = sock_filter_convert_ctx_access, }; @@ -3805,6 +4252,13 @@ const struct bpf_verifier_ops sock_ops_prog_ops = { .convert_ctx_access = sock_ops_convert_ctx_access, }; +const struct bpf_verifier_ops sk_skb_prog_ops = { + .get_func_proto = sk_skb_func_proto, + .is_valid_access = sk_skb_is_valid_access, + .convert_ctx_access = bpf_convert_ctx_access, + .gen_prologue = sk_skb_prologue, +}; + int sk_detach_filter(struct sock *sk) { int ret = -ENOENT; |