/* Copyright (c) 2015 PLUMgrid, http://plumgrid.com * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. */ #include #include "bpf_helpers.h" #include #include #include #include #include #include #include #define IP_MF 0x2000 #define IP_OFFSET 0x1FFF #define PROG(F) SEC("socket/"__stringify(F)) int bpf_func_##F struct bpf_map_def SEC("maps") jmp_table = { .type = BPF_MAP_TYPE_PROG_ARRAY, .key_size = sizeof(u32), .value_size = sizeof(u32), .max_entries = 8, }; #define PARSE_VLAN 1 #define PARSE_MPLS 2 #define PARSE_IP 3 #define PARSE_IPV6 4 /* protocol dispatch routine. * It tail-calls next BPF program depending on eth proto * Note, we could have used: * bpf_tail_call(skb, &jmp_table, proto); * but it would need large prog_array */ static inline void parse_eth_proto(struct __sk_buff *skb, u32 proto) { switch (proto) { case ETH_P_8021Q: case ETH_P_8021AD: bpf_tail_call(skb, &jmp_table, PARSE_VLAN); break; case ETH_P_MPLS_UC: case ETH_P_MPLS_MC: bpf_tail_call(skb, &jmp_table, PARSE_MPLS); break; case ETH_P_IP: bpf_tail_call(skb, &jmp_table, PARSE_IP); break; case ETH_P_IPV6: bpf_tail_call(skb, &jmp_table, PARSE_IPV6); break; } } struct vlan_hdr { __be16 h_vlan_TCI; __be16 h_vlan_encapsulated_proto; }; struct bpf_flow_keys { __be32 src; __be32 dst; union { __be32 ports; __be16 port16[2]; }; __u32 ip_proto; }; static inline int ip_is_fragment(struct __sk_buff *ctx, __u64 nhoff) { return load_half(ctx, nhoff + offsetof(struct iphdr, frag_off)) & (IP_MF | IP_OFFSET); } static inline __u32 ipv6_addr_hash(struct __sk_buff *ctx, __u64 off) { __u64 w0 = load_word(ctx, off); __u64 w1 = load_word(ctx, off + 4); __u64 w2 = load_word(ctx, off + 8); __u64 w3 = load_word(ctx, off + 12); return (__u32)(w0 ^ w1 ^ w2 ^ w3); } struct globals { struct bpf_flow_keys flow; }; struct bpf_map_def SEC("maps") percpu_map = { .type = BPF_MAP_TYPE_ARRAY, .key_size = sizeof(__u32), .value_size = sizeof(struct globals), .max_entries = 32, }; /* user poor man's per_cpu until native support is ready */ static struct globals *this_cpu_globals(void) { u32 key = bpf_get_smp_processor_id(); return bpf_map_lookup_elem(&percpu_map, &key); } /* some simple stats for user space consumption */ struct pair { __u64 packets; __u64 bytes; }; struct bpf_map_def SEC("maps") hash_map = { .type = BPF_MAP_TYPE_HASH, .key_size = sizeof(struct bpf_flow_keys), .value_size = sizeof(struct pair), .max_entries = 1024, }; static void update_stats(struct __sk_buff *skb, struct globals *g) { struct bpf_flow_keys key = g->flow; struct pair *value; value = bpf_map_lookup_elem(&hash_map, &key); if (value) { __sync_fetch_and_add(&value->packets, 1); __sync_fetch_and_add(&value->bytes, skb->len); } else { struct pair val = {1, skb->len}; bpf_map_update_elem(&hash_map, &key, &val, BPF_ANY); } } static __always_inline void parse_ip_proto(struct __sk_buff *skb, struct globals *g, __u32 ip_proto) { __u32 nhoff = skb->cb[0]; int poff; switch (ip_proto) { case IPPROTO_GRE: { struct gre_hdr { __be16 flags; __be16 proto; }; __u32 gre_flags = load_half(skb, nhoff + offsetof(struct gre_hdr, flags)); __u32 gre_proto = load_half(skb, nhoff + offsetof(struct gre_hdr, proto)); if (gre_flags & (GRE_VERSION|GRE_ROUTING)) break; nhoff += 4; if (gre_flags & GRE_CSUM) nhoff += 4; if (gre_flags & GRE_KEY) nhoff += 4; if (gre_flags & GRE_SEQ) nhoff += 4; skb->cb[0] = nhoff; parse_eth_proto(skb, gre_proto); break; } case IPPROTO_IPIP: parse_eth_proto(skb, ETH_P_IP); break; case IPPROTO_IPV6: parse_eth_proto(skb, ETH_P_IPV6); break; case IPPROTO_TCP: case IPPROTO_UDP: g->flow.ports = load_word(skb, nhoff); case IPPROTO_ICMP: g->flow.ip_proto = ip_proto; update_stats(skb, g); break; default: break; } } PROG(PARSE_IP)(struct __sk_buff *skb) { struct globals *g = this_cpu_globals(); __u32 nhoff, verlen, ip_proto; if (!g) return 0; nhoff = skb->cb[0]; if (unlikely(ip_is_fragment(skb, nhoff))) return 0; ip_proto = load_byte(skb, nhoff + offsetof(struct iphdr, protocol)); if (ip_proto != IPPROTO_GRE) { g->flow.src = load_word(skb, nhoff + offsetof(struct iphdr, saddr)); g->flow.dst = load_word(skb, nhoff + offsetof(struct iphdr, daddr)); } verlen = load_byte(skb, nhoff + 0/*offsetof(struct iphdr, ihl)*/); nhoff += (verlen & 0xF) << 2; skb->cb[0] = nhoff; parse_ip_proto(skb, g, ip_proto); return 0; } PROG(PARSE_IPV6)(struct __sk_buff *skb) { struct globals *g = this_cpu_globals(); __u32 nhoff, ip_proto; if (!g) return 0; nhoff = skb->cb[0]; ip_proto = load_byte(skb, nhoff + offsetof(struct ipv6hdr, nexthdr)); g->flow.src = ipv6_addr_hash(skb, nhoff + offsetof(struct ipv6hdr, saddr)); g->flow.dst = ipv6_addr_hash(skb, nhoff + offsetof(struct ipv6hdr, daddr)); nhoff += sizeof(struct ipv6hdr); skb->cb[0] = nhoff; parse_ip_proto(skb, g, ip_proto); return 0; } PROG(PARSE_VLAN)(struct __sk_buff *skb) { __u32 nhoff, proto; nhoff = skb->cb[0]; proto = load_half(skb, nhoff + offsetof(struct vlan_hdr, h_vlan_encapsulated_proto)); nhoff += sizeof(struct vlan_hdr); skb->cb[0] = nhoff; parse_eth_proto(skb, proto); return 0; } PROG(PARSE_MPLS)(struct __sk_buff *skb) { __u32 nhoff, label; nhoff = skb->cb[0]; label = load_word(skb, nhoff); nhoff += sizeof(struct mpls_label); skb->cb[0] = nhoff; if (label & MPLS_LS_S_MASK) { __u8 verlen = load_byte(skb, nhoff); if ((verlen & 0xF0) == 4) parse_eth_proto(skb, ETH_P_IP); else parse_eth_proto(skb, ETH_P_IPV6); } else { parse_eth_proto(skb, ETH_P_MPLS_UC); } return 0; } SEC("socket/0") int main_prog(struct __sk_buff *skb) { __u32 nhoff = ETH_HLEN; __u32 proto = load_half(skb, 12); skb->cb[0] = nhoff; parse_eth_proto(skb, proto); return 0; } char _license[] SEC("license") = "GPL"; inadvertently created an issue with such firmware, by moving some of the FDT manipulation to after the invocation of ExitBootServices(). Given that the stub's libfdt implementation uses the ordinary, accelerated string functions, which rely on hardware handling of unaligned accesses, manipulating the FDT with the MMU off may result in alignment faults. So fix the situation by moving the update_fdt_memmap() call into the callback function invoked by efi_exit_boot_services() right before it calls the ExitBootServices() UEFI service (which is arguably a better place for it anyway) Note that disabling the MMU in ExitBootServices() is not compliant with the UEFI spec, and carries great risk due to the fact that switching from cached to uncached memory accesses halfway through compiler generated code (i.e., involving a stack) can never be done in a way that is architecturally safe. Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Riku Voipio <riku.voipio@linaro.org> Cc: <stable@vger.kernel.org> Cc: mark.rutland@arm.com Cc: linux-efi@vger.kernel.org Cc: matt@codeblueprint.co.uk Cc: leif.lindholm@linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'security/smack/smack.h')