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alistair23-linux/net/core/filter.c
Gianluca Borello db1ac4964f bpf: introduce ARG_PTR_TO_MEM_OR_NULL 
With the current ARG_PTR_TO_MEM/ARG_PTR_TO_UNINIT_MEM semantics, an helper
argument can be NULL when the next argument type is ARG_CONST_SIZE_OR_ZERO
and the verifier can prove the value of this next argument is 0. However,
most helpers are just interested in handling <!NULL, 0>, so forcing them to
deal with <NULL, 0> makes the implementation of those helpers more
complicated for no apparent benefits, requiring them to explicitly handle
those corner cases with checks that bpf programs could start relying upon,
preventing the possibility of removing them later.

Solve this by making ARG_PTR_TO_MEM/ARG_PTR_TO_UNINIT_MEM never accept NULL
even when ARG_CONST_SIZE_OR_ZERO is set, and introduce a new argument type
ARG_PTR_TO_MEM_OR_NULL to explicitly deal with the NULL case.

Currently, the only helper that needs this is bpf_csum_diff_proto(), so
change arg1 and arg3 to this new type as well.

Also add a new battery of tests that explicitly test the
!ARG_PTR_TO_MEM_OR_NULL combination: all the current ones testing the
various <NULL, 0> variations are focused on bpf_csum_diff, so cover also
other helpers.

Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-22 21:40:54 +01:00

4621 lines
119 KiB
C
Raw Blame History

/*
* Linux Socket Filter - Kernel level socket filtering
*
* Based on the design of the Berkeley Packet Filter. The new
* internal format has been designed by PLUMgrid:
*
* Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
*
* Authors:
*
* Jay Schulist <jschlst@samba.org>
* Alexei Starovoitov <ast@plumgrid.com>
* Daniel Borkmann <dborkman@redhat.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Andi Kleen - Fix a few bad bugs and races.
* Kris Katterjohn - Added many additional checks in bpf_check_classic()
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/fcntl.h>
#include <linux/socket.h>
#include <linux/sock_diag.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/if_packet.h>
#include <linux/if_arp.h>
#include <linux/gfp.h>
#include <net/ip.h>
#include <net/protocol.h>
#include <net/netlink.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <net/flow_dissector.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <linux/uaccess.h>
#include <asm/unaligned.h>
#include <asm/cmpxchg.h>
#include <linux/filter.h>
#include <linux/ratelimit.h>
#include <linux/seccomp.h>
#include <linux/if_vlan.h>
#include <linux/bpf.h>
#include <net/sch_generic.h>
#include <net/cls_cgroup.h>
#include <net/dst_metadata.h>
#include <net/dst.h>
#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
* @sk: sock associated with &sk_buff
* @skb: buffer to filter
* @cap: limit on how short the eBPF program may trim the packet
*
* Run the eBPF program and then cut skb->data to correct size returned by
* the program. If pkt_len is 0 we toss packet. If skb->len is smaller
* than pkt_len we keep whole skb->data. This is the socket level
* wrapper to BPF_PROG_RUN. It returns 0 if the packet should
* be accepted or -EPERM if the packet should be tossed.
*
*/
int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap)
{
int err;
struct sk_filter *filter;
/*
* If the skb was allocated from pfmemalloc reserves, only
* allow SOCK_MEMALLOC sockets to use it as this socket is
* helping free memory
*/
if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) {
NET_INC_STATS(sock_net(sk), LINUX_MIB_PFMEMALLOCDROP);
return -ENOMEM;
}
err = BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb);
if (err)
return err;
err = security_sock_rcv_skb(sk, skb);
if (err)
return err;
rcu_read_lock();
filter = rcu_dereference(sk->sk_filter);
if (filter) {
struct sock *save_sk = skb->sk;
unsigned int pkt_len;
skb->sk = sk;
pkt_len = bpf_prog_run_save_cb(filter->prog, skb);
skb->sk = save_sk;
err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM;
}
rcu_read_unlock();
return err;
}
EXPORT_SYMBOL(sk_filter_trim_cap);
BPF_CALL_1(__skb_get_pay_offset, struct sk_buff *, skb)
{
return skb_get_poff(skb);
}
BPF_CALL_3(__skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x)
{
struct nlattr *nla;
if (skb_is_nonlinear(skb))
return 0;
if (skb->len < sizeof(struct nlattr))
return 0;
if (a > skb->len - sizeof(struct nlattr))
return 0;
nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x);
if (nla)
return (void *) nla - (void *) skb->data;
return 0;
}
BPF_CALL_3(__skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x)
{
struct nlattr *nla;
if (skb_is_nonlinear(skb))
return 0;
if (skb->len < sizeof(struct nlattr))
return 0;
if (a > skb->len - sizeof(struct nlattr))
return 0;
nla = (struct nlattr *) &skb->data[a];
if (nla->nla_len > skb->len - a)
return 0;
nla = nla_find_nested(nla, x);
if (nla)
return (void *) nla - (void *) skb->data;
return 0;
}
BPF_CALL_0(__get_raw_cpu_id)
{
return raw_smp_processor_id();
}
static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto = {
.func = __get_raw_cpu_id,
.gpl_only = false,
.ret_type = RET_INTEGER,
};
static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
struct bpf_insn *insn_buf)
{
struct bpf_insn *insn = insn_buf;
switch (skb_field) {
case SKF_AD_MARK:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4);
*insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
offsetof(struct sk_buff, mark));
break;
case SKF_AD_PKTTYPE:
*insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET());
*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX);
#ifdef __BIG_ENDIAN_BITFIELD
*insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5);
#endif
break;
case SKF_AD_QUEUE:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, queue_mapping) != 2);
*insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
offsetof(struct sk_buff, queue_mapping));
break;
case SKF_AD_VLAN_TAG:
case SKF_AD_VLAN_TAG_PRESENT:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2);
BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
/* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
*insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
offsetof(struct sk_buff, vlan_tci));
if (skb_field == SKF_AD_VLAN_TAG) {
*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg,
~VLAN_TAG_PRESENT);
} else {
/* dst_reg >>= 12 */
*insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 12);
/* dst_reg &= 1 */
*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1);
}
break;
}
return insn - insn_buf;
}
static bool convert_bpf_extensions(struct sock_filter *fp,
struct bpf_insn **insnp)
{
struct bpf_insn *insn = *insnp;
u32 cnt;
switch (fp->k) {
case SKF_AD_OFF + SKF_AD_PROTOCOL:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, protocol) != 2);
/* A = *(u16 *) (CTX + offsetof(protocol)) */
*insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
offsetof(struct sk_buff, protocol));
/* A = ntohs(A) [emitting a nop or swap16] */
*insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
break;
case SKF_AD_OFF + SKF_AD_PKTTYPE:
cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn);
insn += cnt - 1;
break;
case SKF_AD_OFF + SKF_AD_IFINDEX:
case SKF_AD_OFF + SKF_AD_HATYPE:
BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4);
BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, type) != 2);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
BPF_REG_TMP, BPF_REG_CTX,
offsetof(struct sk_buff, dev));
/* if (tmp != 0) goto pc + 1 */
*insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1);
*insn++ = BPF_EXIT_INSN();
if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX)
*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP,
offsetof(struct net_device, ifindex));
else
*insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP,
offsetof(struct net_device, type));
break;
case SKF_AD_OFF + SKF_AD_MARK:
cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn);
insn += cnt - 1;
break;
case SKF_AD_OFF + SKF_AD_RXHASH:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, hash) != 4);
*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX,
offsetof(struct sk_buff, hash));
break;
case SKF_AD_OFF + SKF_AD_QUEUE:
cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn);
insn += cnt - 1;
break;
case SKF_AD_OFF + SKF_AD_VLAN_TAG:
cnt = convert_skb_access(SKF_AD_VLAN_TAG,
BPF_REG_A, BPF_REG_CTX, insn);
insn += cnt - 1;
break;
case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT,
BPF_REG_A, BPF_REG_CTX, insn);
insn += cnt - 1;
break;
case SKF_AD_OFF + SKF_AD_VLAN_TPID:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_proto) != 2);
/* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
*insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
offsetof(struct sk_buff, vlan_proto));
/* A = ntohs(A) [emitting a nop or swap16] */
*insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
break;
case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
case SKF_AD_OFF + SKF_AD_NLATTR:
case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
case SKF_AD_OFF + SKF_AD_CPU:
case SKF_AD_OFF + SKF_AD_RANDOM:
/* arg1 = CTX */
*insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
/* arg2 = A */
*insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A);
/* arg3 = X */
*insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X);
/* Emit call(arg1=CTX, arg2=A, arg3=X) */
switch (fp->k) {
case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
*insn = BPF_EMIT_CALL(__skb_get_pay_offset);
break;
case SKF_AD_OFF + SKF_AD_NLATTR:
*insn = BPF_EMIT_CALL(__skb_get_nlattr);
break;
case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
*insn = BPF_EMIT_CALL(__skb_get_nlattr_nest);
break;
case SKF_AD_OFF + SKF_AD_CPU:
*insn = BPF_EMIT_CALL(__get_raw_cpu_id);
break;
case SKF_AD_OFF + SKF_AD_RANDOM:
*insn = BPF_EMIT_CALL(bpf_user_rnd_u32);
bpf_user_rnd_init_once();
break;
}
break;
case SKF_AD_OFF + SKF_AD_ALU_XOR_X:
/* A ^= X */
*insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X);
break;
default:
/* This is just a dummy call to avoid letting the compiler
* evict __bpf_call_base() as an optimization. Placed here
* where no-one bothers.
*/
BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
return false;
}
*insnp = insn;
return true;
}
/**
* bpf_convert_filter - convert filter program
* @prog: the user passed filter program
* @len: the length of the user passed filter program
* @new_prog: allocated 'struct bpf_prog' or NULL
* @new_len: pointer to store length of converted program
*
* Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn'
* style extended BPF (eBPF).
* Conversion workflow:
*
* 1) First pass for calculating the new program length:
* bpf_convert_filter(old_prog, old_len, NULL, &new_len)
*
* 2) 2nd pass to remap in two passes: 1st pass finds new
* jump offsets, 2nd pass remapping:
* bpf_convert_filter(old_prog, old_len, new_prog, &new_len);
*/
static int bpf_convert_filter(struct sock_filter *prog, int len,
struct bpf_prog *new_prog, int *new_len)
{
int new_flen = 0, pass = 0, target, i, stack_off;
struct bpf_insn *new_insn, *first_insn = NULL;
struct sock_filter *fp;
int *addrs = NULL;
u8 bpf_src;
BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK);
BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG);
if (len <= 0 || len > BPF_MAXINSNS)
return -EINVAL;
if (new_prog) {
first_insn = new_prog->insnsi;
addrs = kcalloc(len, sizeof(*addrs),
GFP_KERNEL | __GFP_NOWARN);
if (!addrs)
return -ENOMEM;
}
do_pass:
new_insn = first_insn;
fp = prog;
/* Classic BPF related prologue emission. */
if (new_prog) {
/* Classic BPF expects A and X to be reset first. These need
* to be guaranteed to be the first two instructions.
*/
*new_insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
*new_insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_X, BPF_REG_X);
/* All programs must keep CTX in callee saved BPF_REG_CTX.
* In eBPF case it's done by the compiler, here we need to
* do this ourself. Initial CTX is present in BPF_REG_ARG1.
*/
*new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1);
} else {
new_insn += 3;
}
for (i = 0; i < len; fp++, i++) {
struct bpf_insn tmp_insns[6] = { };
struct bpf_insn *insn = tmp_insns;
if (addrs)
addrs[i] = new_insn - first_insn;
switch (fp->code) {
/* All arithmetic insns and skb loads map as-is. */
case BPF_ALU | BPF_ADD | BPF_X:
case BPF_ALU | BPF_ADD | BPF_K:
case BPF_ALU | BPF_SUB | BPF_X:
case BPF_ALU | BPF_SUB | BPF_K:
case BPF_ALU | BPF_AND | BPF_X:
case BPF_ALU | BPF_AND | BPF_K:
case BPF_ALU | BPF_OR | BPF_X:
case BPF_ALU | BPF_OR | BPF_K:
case BPF_ALU | BPF_LSH | BPF_X:
case BPF_ALU | BPF_LSH | BPF_K:
case BPF_ALU | BPF_RSH | BPF_X:
case BPF_ALU | BPF_RSH | BPF_K:
case BPF_ALU | BPF_XOR | BPF_X:
case BPF_ALU | BPF_XOR | BPF_K:
case BPF_ALU | BPF_MUL | BPF_X:
case BPF_ALU | BPF_MUL | BPF_K:
case BPF_ALU | BPF_DIV | BPF_X:
case BPF_ALU | BPF_DIV | BPF_K:
case BPF_ALU | BPF_MOD | BPF_X:
case BPF_ALU | BPF_MOD | BPF_K:
case BPF_ALU | BPF_NEG:
case BPF_LD | BPF_ABS | BPF_W:
case BPF_LD | BPF_ABS | BPF_H:
case BPF_LD | BPF_ABS | BPF_B:
case BPF_LD | BPF_IND | BPF_W:
case BPF_LD | BPF_IND | BPF_H:
case BPF_LD | BPF_IND | BPF_B:
/* Check for overloaded BPF extension and
* directly convert it if found, otherwise
* just move on with mapping.
*/
if (BPF_CLASS(fp->code) == BPF_LD &&
BPF_MODE(fp->code) == BPF_ABS &&
convert_bpf_extensions(fp, &insn))
break;
*insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k);
break;
/* Jump transformation cannot use BPF block macros
* everywhere as offset calculation and target updates
* require a bit more work than the rest, i.e. jump
* opcodes map as-is, but offsets need adjustment.
*/
#define BPF_EMIT_JMP \
do { \
if (target >= len || target < 0) \
goto err; \
insn->off = addrs ? addrs[target] - addrs[i] - 1 : 0; \
/* Adjust pc relative offset for 2nd or 3rd insn. */ \
insn->off -= insn - tmp_insns; \
} while (0)
case BPF_JMP | BPF_JA:
target = i + fp->k + 1;
insn->code = fp->code;
BPF_EMIT_JMP;
break;
case BPF_JMP | BPF_JEQ | BPF_K:
case BPF_JMP | BPF_JEQ | BPF_X:
case BPF_JMP | BPF_JSET | BPF_K:
case BPF_JMP | BPF_JSET | BPF_X:
case BPF_JMP | BPF_JGT | BPF_K:
case BPF_JMP | BPF_JGT | BPF_X:
case BPF_JMP | BPF_JGE | BPF_K:
case BPF_JMP | BPF_JGE | BPF_X:
if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) {
/* BPF immediates are signed, zero extend
* immediate into tmp register and use it
* in compare insn.
*/
*insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k);
insn->dst_reg = BPF_REG_A;
insn->src_reg = BPF_REG_TMP;
bpf_src = BPF_X;
} else {
insn->dst_reg = BPF_REG_A;
insn->imm = fp->k;
bpf_src = BPF_SRC(fp->code);
insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0;
}
/* Common case where 'jump_false' is next insn. */
if (fp->jf == 0) {
insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
target = i + fp->jt + 1;
BPF_EMIT_JMP;
break;
}
/* 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;
BPF_EMIT_JMP;
insn++;
insn->code = BPF_JMP | BPF_JA;
target = i + fp->jf + 1;
BPF_EMIT_JMP;
break;
/* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
case BPF_LDX | BPF_MSH | BPF_B:
/* tmp = A */
*insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_A);
/* A = BPF_R0 = *(u8 *) (skb->data + K) */
*insn++ = BPF_LD_ABS(BPF_B, fp->k);
/* A &= 0xf */
*insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf);
/* A <<= 2 */
*insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2);
/* X = A */
*insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
/* A = tmp */
*insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP);
break;
/* RET_K is remaped into 2 insns. RET_A case doesn't need an
* extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
*/
case BPF_RET | BPF_A:
case BPF_RET | BPF_K:
if (BPF_RVAL(fp->code) == BPF_K)
*insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0,
0, fp->k);
*insn = BPF_EXIT_INSN();
break;
/* Store to stack. */
case BPF_ST:
case BPF_STX:
stack_off = fp->k * 4 + 4;
*insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) ==
BPF_ST ? BPF_REG_A : BPF_REG_X,
-stack_off);
/* check_load_and_stores() verifies that classic BPF can
* load from stack only after write, so tracking
* stack_depth for ST|STX insns is enough
*/
if (new_prog && new_prog->aux->stack_depth < stack_off)
new_prog->aux->stack_depth = stack_off;
break;
/* Load from stack. */
case BPF_LD | BPF_MEM:
case BPF_LDX | BPF_MEM:
stack_off = fp->k * 4 + 4;
*insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
BPF_REG_A : BPF_REG_X, BPF_REG_FP,
-stack_off);
break;
/* A = K or X = K */
case BPF_LD | BPF_IMM:
case BPF_LDX | BPF_IMM:
*insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ?
BPF_REG_A : BPF_REG_X, fp->k);
break;
/* X = A */
case BPF_MISC | BPF_TAX:
*insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
break;
/* A = X */
case BPF_MISC | BPF_TXA:
*insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X);
break;
/* A = skb->len or X = skb->len */
case BPF_LD | BPF_W | BPF_LEN:
case BPF_LDX | BPF_W | BPF_LEN:
*insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
BPF_REG_A : BPF_REG_X, BPF_REG_CTX,
offsetof(struct sk_buff, len));
break;
/* Access seccomp_data fields. */
case BPF_LDX | BPF_ABS | BPF_W:
/* A = *(u32 *) (ctx + K) */
*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k);
break;
/* Unknown instruction. */
default:
goto err;
}
insn++;
if (new_prog)
memcpy(new_insn, tmp_insns,
sizeof(*insn) * (insn - tmp_insns));
new_insn += insn - tmp_insns;
}
if (!new_prog) {
/* Only calculating new length. */
*new_len = new_insn - first_insn;
return 0;
}
pass++;
if (new_flen != new_insn - first_insn) {
new_flen = new_insn - first_insn;
if (pass > 2)
goto err;
goto do_pass;
}
kfree(addrs);
BUG_ON(*new_len != new_flen);
return 0;
err:
kfree(addrs);
return -EINVAL;
}
/* Security:
*
* As we dont want to clear mem[] array for each packet going through
* __bpf_prog_run(), we check that filter loaded by user never try to read
* a cell if not previously written, and we check all branches to be sure
* a malicious user doesn't try to abuse us.
*/
static int check_load_and_stores(const struct sock_filter *filter, int flen)
{
u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */
int pc, ret = 0;
BUILD_BUG_ON(BPF_MEMWORDS > 16);
masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL);
if (!masks)
return -ENOMEM;
memset(masks, 0xff, flen * sizeof(*masks));
for (pc = 0; pc < flen; pc++) {
memvalid &= masks[pc];
switch (filter[pc].code) {
case BPF_ST:
case BPF_STX:
memvalid |= (1 << filter[pc].k);
break;
case BPF_LD | BPF_MEM:
case BPF_LDX | BPF_MEM:
if (!(memvalid & (1 << filter[pc].k))) {
ret = -EINVAL;
goto error;
}
break;
case BPF_JMP | BPF_JA:
/* A jump must set masks on target */
masks[pc + 1 + filter[pc].k] &= memvalid;
memvalid = ~0;
break;
case BPF_JMP | BPF_JEQ | BPF_K:
case BPF_JMP | BPF_JEQ | BPF_X:
case BPF_JMP | BPF_JGE | BPF_K:
case BPF_JMP | BPF_JGE | BPF_X:
case BPF_JMP | BPF_JGT | BPF_K:
case BPF_JMP | BPF_JGT | BPF_X:
case BPF_JMP | BPF_JSET | BPF_K:
case BPF_JMP | BPF_JSET | BPF_X:
/* A jump must set masks on targets */
masks[pc + 1 + filter[pc].jt] &= memvalid;
masks[pc + 1 + filter[pc].jf] &= memvalid;
memvalid = ~0;
break;
}
}
error:
kfree(masks);
return ret;
}
static bool chk_code_allowed(u16 code_to_probe)
{
static const bool codes[] = {
/* 32 bit ALU operations */
[BPF_ALU | BPF_ADD | BPF_K] = true,
[BPF_ALU | BPF_ADD | BPF_X] = true,
[BPF_ALU | BPF_SUB | BPF_K] = true,
[BPF_ALU | BPF_SUB | BPF_X] = true,
[BPF_ALU | BPF_MUL | BPF_K] = true,
[BPF_ALU | BPF_MUL | BPF_X] = true,
[BPF_ALU | BPF_DIV | BPF_K] = true,
[BPF_ALU | BPF_DIV | BPF_X] = true,
[BPF_ALU | BPF_MOD | BPF_K] = true,
[BPF_ALU | BPF_MOD | BPF_X] = true,
[BPF_ALU | BPF_AND | BPF_K] = true,
[BPF_ALU | BPF_AND | BPF_X] = true,
[BPF_ALU | BPF_OR | BPF_K] = true,
[BPF_ALU | BPF_OR | BPF_X] = true,
[BPF_ALU | BPF_XOR | BPF_K] = true,
[BPF_ALU | BPF_XOR | BPF_X] = true,
[BPF_ALU | BPF_LSH | BPF_K] = true,
[BPF_ALU | BPF_LSH | BPF_X] = true,
[BPF_ALU | BPF_RSH | BPF_K] = true,
[BPF_ALU | BPF_RSH | BPF_X] = true,
[BPF_ALU | BPF_NEG] = true,
/* Load instructions */
[BPF_LD | BPF_W | BPF_ABS] = true,
[BPF_LD | BPF_H | BPF_ABS] = true,
[BPF_LD | BPF_B | BPF_ABS] = true,
[BPF_LD | BPF_W | BPF_LEN] = true,
[BPF_LD | BPF_W | BPF_IND] = true,
[BPF_LD | BPF_H | BPF_IND] = true,
[BPF_LD | BPF_B | BPF_IND] = true,
[BPF_LD | BPF_IMM] = true,
[BPF_LD | BPF_MEM] = true,
[BPF_LDX | BPF_W | BPF_LEN] = true,
[BPF_LDX | BPF_B | BPF_MSH] = true,
[BPF_LDX | BPF_IMM] = true,
[BPF_LDX | BPF_MEM] = true,
/* Store instructions */
[BPF_ST] = true,
[BPF_STX] = true,
/* Misc instructions */
[BPF_MISC | BPF_TAX] = true,
[BPF_MISC | BPF_TXA] = true,
/* Return instructions */
[BPF_RET | BPF_K] = true,
[BPF_RET | BPF_A] = true,
/* Jump instructions */
[BPF_JMP | BPF_JA] = true,
[BPF_JMP | BPF_JEQ | BPF_K] = true,
[BPF_JMP | BPF_JEQ | BPF_X] = true,
[BPF_JMP | BPF_JGE | BPF_K] = true,
[BPF_JMP | BPF_JGE | BPF_X] = true,
[BPF_JMP | BPF_JGT | BPF_K] = true,
[BPF_JMP | BPF_JGT | BPF_X] = true,
[BPF_JMP | BPF_JSET | BPF_K] = true,
[BPF_JMP | BPF_JSET | BPF_X] = true,
};
if (code_to_probe >= ARRAY_SIZE(codes))
return false;
return codes[code_to_probe];
}
static bool bpf_check_basics_ok(const struct sock_filter *filter,
unsigned int flen)
{
if (filter == NULL)
return false;
if (flen == 0 || flen > BPF_MAXINSNS)
return false;
return true;
}
/**
* bpf_check_classic - verify socket filter code
* @filter: filter to verify
* @flen: length of filter
*
* Check the user's filter code. If we let some ugly
* filter code slip through kaboom! The filter must contain
* no references or jumps that are out of range, no illegal
* instructions, and must end with a RET instruction.
*
* All jumps are forward as they are not signed.
*
* Returns 0 if the rule set is legal or -EINVAL if not.
*/
static int bpf_check_classic(const struct sock_filter *filter,
unsigned int flen)
{
bool anc_found;
int pc;
/* Check the filter code now */
for (pc = 0; pc < flen; pc++) {
const struct sock_filter *ftest = &filter[pc];
/* May we actually operate on this code? */
if (!chk_code_allowed(ftest->code))
return -EINVAL;
/* Some instructions need special checks */
switch (ftest->code) {
case BPF_ALU | BPF_DIV | BPF_K:
case BPF_ALU | BPF_MOD | BPF_K:
/* Check for division by zero */
if (ftest->k == 0)
return -EINVAL;
break;
case BPF_ALU | BPF_LSH | BPF_K:
case BPF_ALU | BPF_RSH | BPF_K:
if (ftest->k >= 32)
return -EINVAL;
break;
case BPF_LD | BPF_MEM:
case BPF_LDX | BPF_MEM:
case BPF_ST:
case BPF_STX:
/* Check for invalid memory addresses */
if (ftest->k >= BPF_MEMWORDS)
return -EINVAL;
break;
case BPF_JMP | BPF_JA:
/* Note, the large ftest->k might cause loops.
* Compare this with conditional jumps below,
* where offsets are limited. --ANK (981016)
*/
if (ftest->k >= (unsigned int)(flen - pc - 1))
return -EINVAL;
break;
case BPF_JMP | BPF_JEQ | BPF_K:
case BPF_JMP | BPF_JEQ | BPF_X:
case BPF_JMP | BPF_JGE | BPF_K:
case BPF_JMP | BPF_JGE | BPF_X:
case BPF_JMP | BPF_JGT | BPF_K:
case BPF_JMP | BPF_JGT | BPF_X:
case BPF_JMP | BPF_JSET | BPF_K:
case BPF_JMP | BPF_JSET | BPF_X:
/* Both conditionals must be safe */
if (pc + ftest->jt + 1 >= flen ||
pc + ftest->jf + 1 >= flen)
return -EINVAL;
break;
case BPF_LD | BPF_W | BPF_ABS:
case BPF_LD | BPF_H | BPF_ABS:
case BPF_LD | BPF_B | BPF_ABS:
anc_found = false;
if (bpf_anc_helper(ftest) & BPF_ANC)
anc_found = true;
/* Ancillary operation unknown or unsupported */
if (anc_found == false && ftest->k >= SKF_AD_OFF)
return -EINVAL;
}
}
/* Last instruction must be a RET code */
switch (filter[flen - 1].code) {
case BPF_RET | BPF_K:
case BPF_RET | BPF_A:
return check_load_and_stores(filter, flen);
}
return -EINVAL;
}
static int bpf_prog_store_orig_filter(struct bpf_prog *fp,
const struct sock_fprog *fprog)
{
unsigned int fsize = bpf_classic_proglen(fprog);
struct sock_fprog_kern *fkprog;
fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL);
if (!fp->orig_prog)
return -ENOMEM;
fkprog = fp->orig_prog;
fkprog->len = fprog->len;
fkprog->filter = kmemdup(fp->insns, fsize,
GFP_KERNEL | __GFP_NOWARN);
if (!fkprog->filter) {
kfree(fp->orig_prog);
return -ENOMEM;
}
return 0;
}
static void bpf_release_orig_filter(struct bpf_prog *fp)
{
struct sock_fprog_kern *fprog = fp->orig_prog;
if (fprog) {
kfree(fprog->filter);
kfree(fprog);
}
}
static void __bpf_prog_release(struct bpf_prog *prog)
{
if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) {
bpf_prog_put(prog);
} else {
bpf_release_orig_filter(prog);
bpf_prog_free(prog);
}
}
static void __sk_filter_release(struct sk_filter *fp)
{
__bpf_prog_release(fp->prog);
kfree(fp);
}
/**
* sk_filter_release_rcu - Release a socket filter by rcu_head
* @rcu: rcu_head that contains the sk_filter to free
*/
static void sk_filter_release_rcu(struct rcu_head *rcu)
{
struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
__sk_filter_release(fp);
}
/**
* sk_filter_release - release a socket filter
* @fp: filter to remove
*
* Remove a filter from a socket and release its resources.
*/
static void sk_filter_release(struct sk_filter *fp)
{
if (refcount_dec_and_test(&fp->refcnt))
call_rcu(&fp->rcu, sk_filter_release_rcu);
}
void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
{
u32 filter_size = bpf_prog_size(fp->prog->len);
atomic_sub(filter_size, &sk->sk_omem_alloc);
sk_filter_release(fp);
}
/* try to charge the socket memory if there is space available
* return true on success
*/
static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp)
{
u32 filter_size = bpf_prog_size(fp->prog->len);
/* same check as in sock_kmalloc() */
if (filter_size <= sysctl_optmem_max &&
atomic_read(&sk->sk_omem_alloc) + filter_size < sysctl_optmem_max) {
atomic_add(filter_size, &sk->sk_omem_alloc);
return true;
}
return false;
}
bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
{
if (!refcount_inc_not_zero(&fp->refcnt))
return false;
if (!__sk_filter_charge(sk, fp)) {
sk_filter_release(fp);
return false;
}
return true;
}
static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
{
struct sock_filter *old_prog;
struct bpf_prog *old_fp;
int err, new_len, old_len = fp->len;
/* We are free to overwrite insns et al right here as it
* won't be used at this point in time anymore internally
* after the migration to the internal BPF instruction
* representation.
*/
BUILD_BUG_ON(sizeof(struct sock_filter) !=
sizeof(struct bpf_insn));
/* Conversion cannot happen on overlapping memory areas,
* so we need to keep the user BPF around until the 2nd
* pass. At this time, the user BPF is stored in fp->insns.
*/
old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter),
GFP_KERNEL | __GFP_NOWARN);
if (!old_prog) {
err = -ENOMEM;
goto out_err;
}
/* 1st pass: calculate the new program length. */
err = bpf_convert_filter(old_prog, old_len, NULL, &new_len);
if (err)
goto out_err_free;
/* Expand fp for appending the new filter representation. */
old_fp = fp;
fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
if (!fp) {
/* The old_fp is still around in case we couldn't
* allocate new memory, so uncharge on that one.
*/
fp = old_fp;
err = -ENOMEM;
goto out_err_free;
}
fp->len = new_len;
/* 2nd pass: remap sock_filter insns into bpf_insn insns. */
err = bpf_convert_filter(old_prog, old_len, fp, &new_len);
if (err)
/* 2nd bpf_convert_filter() can fail only if it fails
* to allocate memory, remapping must succeed. Note,
* that at this time old_fp has already been released
* by krealloc().
*/
goto out_err_free;
/* We are guaranteed to never error here with cBPF to eBPF
* transitions, since there's no issue with type compatibility
* checks on program arrays.
*/
fp = bpf_prog_select_runtime(fp, &err);
kfree(old_prog);
return fp;
out_err_free:
kfree(old_prog);
out_err:
__bpf_prog_release(fp);
return ERR_PTR(err);
}
static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp,
bpf_aux_classic_check_t trans)
{
int err;
fp->bpf_func = NULL;
fp->jited = 0;
err = bpf_check_classic(fp->insns, fp->len);
if (err) {
__bpf_prog_release(fp);
return ERR_PTR(err);
}
/* There might be additional checks and transformations
* needed on classic filters, f.e. in case of seccomp.
*/
if (trans) {
err = trans(fp->insns, fp->len);
if (err) {
__bpf_prog_release(fp);
return ERR_PTR(err);
}
}
/* Probe if we can JIT compile the filter and if so, do
* the compilation of the filter.
*/
bpf_jit_compile(fp);
/* JIT compiler couldn't process this filter, so do the
* internal BPF translation for the optimized interpreter.
*/
if (!fp->jited)
fp = bpf_migrate_filter(fp);
return fp;
}
/**
* bpf_prog_create - create an unattached filter
* @pfp: the unattached filter that is created
* @fprog: the filter program
*
* Create a filter independent of any socket. We first run some
* sanity checks on it to make sure it does not explode on us later.
* If an error occurs or there is insufficient memory for the filter
* a negative errno code is returned. On success the return is zero.
*/
int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
{
unsigned int fsize = bpf_classic_proglen(fprog);
struct bpf_prog *fp;
/* Make sure new filter is there and in the right amounts. */
if (!bpf_check_basics_ok(fprog->filter, fprog->len))
return -EINVAL;
fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
if (!fp)
return -ENOMEM;
memcpy(fp->insns, fprog->filter, fsize);
fp->len = fprog->len;
/* Since unattached filters are not copied back to user
* space through sk_get_filter(), we do not need to hold
* a copy here, and can spare us the work.
*/
fp->orig_prog = NULL;
/* bpf_prepare_filter() already takes care of freeing
* memory in case something goes wrong.
*/
fp = bpf_prepare_filter(fp, NULL);
if (IS_ERR(fp))
return PTR_ERR(fp);
*pfp = fp;
return 0;
}
EXPORT_SYMBOL_GPL(bpf_prog_create);
/**
* bpf_prog_create_from_user - create an unattached filter from user buffer
* @pfp: the unattached filter that is created
* @fprog: the filter program
* @trans: post-classic verifier transformation handler
* @save_orig: save classic BPF program
*
* This function effectively does the same as bpf_prog_create(), only
* that it builds up its insns buffer from user space provided buffer.
* It also allows for passing a bpf_aux_classic_check_t handler.
*/
int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
bpf_aux_classic_check_t trans, bool save_orig)
{
unsigned int fsize = bpf_classic_proglen(fprog);
struct bpf_prog *fp;
int err;
/* Make sure new filter is there and in the right amounts. */
if (!bpf_check_basics_ok(fprog->filter, fprog->len))
return -EINVAL;
fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
if (!fp)
return -ENOMEM;
if (copy_from_user(fp->insns, fprog->filter, fsize)) {
__bpf_prog_free(fp);
return -EFAULT;
}
fp->len = fprog->len;
fp->orig_prog = NULL;
if (save_orig) {
err = bpf_prog_store_orig_filter(fp, fprog);
if (err) {
__bpf_prog_free(fp);
return -ENOMEM;
}
}
/* bpf_prepare_filter() already takes care of freeing
* memory in case something goes wrong.
*/
fp = bpf_prepare_filter(fp, trans);
if (IS_ERR(fp))
return PTR_ERR(fp);
*pfp = fp;
return 0;
}
EXPORT_SYMBOL_GPL(bpf_prog_create_from_user);
void bpf_prog_destroy(struct bpf_prog *fp)
{
__bpf_prog_release(fp);
}
EXPORT_SYMBOL_GPL(bpf_prog_destroy);
static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk)
{
struct sk_filter *fp, *old_fp;
fp = kmalloc(sizeof(*fp), GFP_KERNEL);
if (!fp)
return -ENOMEM;
fp->prog = prog;
if (!__sk_filter_charge(sk, fp)) {
kfree(fp);
return -ENOMEM;
}
refcount_set(&fp->refcnt, 1);
old_fp = rcu_dereference_protected(sk->sk_filter,
lockdep_sock_is_held(sk));
rcu_assign_pointer(sk->sk_filter, fp);
if (old_fp)
sk_filter_uncharge(sk, old_fp);
return 0;
}
static int __reuseport_attach_prog(struct bpf_prog *prog, struct sock *sk)
{
struct bpf_prog *old_prog;
int err;
if (bpf_prog_size(prog->len) > sysctl_optmem_max)
return -ENOMEM;
if (sk_unhashed(sk) && sk->sk_reuseport) {
err = reuseport_alloc(sk);
if (err)
return err;
} else if (!rcu_access_pointer(sk->sk_reuseport_cb)) {
/* The socket wasn't bound with SO_REUSEPORT */
return -EINVAL;
}
old_prog = reuseport_attach_prog(sk, prog);
if (old_prog)
bpf_prog_destroy(old_prog);
return 0;
}
static
struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk)
{
unsigned int fsize = bpf_classic_proglen(fprog);
struct bpf_prog *prog;
int err;
if (sock_flag(sk, SOCK_FILTER_LOCKED))
return ERR_PTR(-EPERM);
/* Make sure new filter is there and in the right amounts. */
if (!bpf_check_basics_ok(fprog->filter, fprog->len))
return ERR_PTR(-EINVAL);
prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
if (!prog)
return ERR_PTR(-ENOMEM);
if (copy_from_user(prog->insns, fprog->filter, fsize)) {
__bpf_prog_free(prog);
return ERR_PTR(-EFAULT);
}
prog->len = fprog->len;
err = bpf_prog_store_orig_filter(prog, fprog);
if (err) {
__bpf_prog_free(prog);
return ERR_PTR(-ENOMEM);
}
/* bpf_prepare_filter() already takes care of freeing
* memory in case something goes wrong.
*/
return bpf_prepare_filter(prog, NULL);
}
/**
* sk_attach_filter - attach a socket filter
* @fprog: the filter program
* @sk: the socket to use
*
* Attach the user's filter code. We first run some sanity checks on
* it to make sure it does not explode on us later. If an error
* occurs or there is insufficient memory for the filter a negative
* errno code is returned. On success the return is zero.
*/
int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
{
struct bpf_prog *prog = __get_filter(fprog, sk);
int err;
if (IS_ERR(prog))
return PTR_ERR(prog);
err = __sk_attach_prog(prog, sk);
if (err < 0) {
__bpf_prog_release(prog);
return err;
}
return 0;
}
EXPORT_SYMBOL_GPL(sk_attach_filter);
int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk)
{
struct bpf_prog *prog = __get_filter(fprog, sk);
int err;
if (IS_ERR(prog))
return PTR_ERR(prog);
err = __reuseport_attach_prog(prog, sk);
if (err < 0) {
__bpf_prog_release(prog);
return err;
}
return 0;
}
static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk)
{
if (sock_flag(sk, SOCK_FILTER_LOCKED))
return ERR_PTR(-EPERM);
return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
}
int sk_attach_bpf(u32 ufd, struct sock *sk)
{
struct bpf_prog *prog = __get_bpf(ufd, sk);
int err;
if (IS_ERR(prog))
return PTR_ERR(prog);
err = __sk_attach_prog(prog, sk);
if (err < 0) {
bpf_prog_put(prog);
return err;
}
return 0;
}
int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk)
{
struct bpf_prog *prog = __get_bpf(ufd, sk);
int err;
if (IS_ERR(prog))
return PTR_ERR(prog);
err = __reuseport_attach_prog(prog, sk);
if (err < 0) {
bpf_prog_put(prog);
return err;
}
return 0;
}
struct bpf_scratchpad {
union {
__be32 diff[MAX_BPF_STACK / sizeof(__be32)];
u8 buff[MAX_BPF_STACK];
};
};
static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp);
static inline int __bpf_try_make_writable(struct sk_buff *skb,
unsigned int write_len)
{
return skb_ensure_writable(skb, write_len);
}
static inline int bpf_try_make_writable(struct sk_buff *skb,
unsigned int write_len)
{
int err = __bpf_try_make_writable(skb, write_len);
bpf_compute_data_pointers(skb);
return err;
}
static int bpf_try_make_head_writable(struct sk_buff *skb)
{
return bpf_try_make_writable(skb, skb_headlen(skb));
}
static inline void bpf_push_mac_rcsum(struct sk_buff *skb)
{
if (skb_at_tc_ingress(skb))
skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len);
}
static inline void bpf_pull_mac_rcsum(struct sk_buff *skb)
{
if (skb_at_tc_ingress(skb))
skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len);
}
BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset,
const void *, from, u32, len, u64, flags)
{
void *ptr;
if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH)))
return -EINVAL;
if (unlikely(offset > 0xffff))
return -EFAULT;
if (unlikely(bpf_try_make_writable(skb, offset + len)))
return -EFAULT;
ptr = skb->data + offset;
if (flags & BPF_F_RECOMPUTE_CSUM)
__skb_postpull_rcsum(skb, ptr, len, offset);
memcpy(ptr, from, len);
if (flags & BPF_F_RECOMPUTE_CSUM)
__skb_postpush_rcsum(skb, ptr, len, offset);
if (flags & BPF_F_INVALIDATE_HASH)
skb_clear_hash(skb);
return 0;
}
static const struct bpf_func_proto bpf_skb_store_bytes_proto = {
.func = bpf_skb_store_bytes,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_PTR_TO_MEM,
.arg4_type = ARG_CONST_SIZE,
.arg5_type = ARG_ANYTHING,
};
BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset,
void *, to, u32, len)
{
void *ptr;
if (unlikely(offset > 0xffff))
goto err_clear;
ptr = skb_header_pointer(skb, offset, len, to);
if (unlikely(!ptr))
goto err_clear;
if (ptr != to)
memcpy(to, ptr, len);
return 0;
err_clear:
memset(to, 0, len);
return -EFAULT;
}
static const struct bpf_func_proto bpf_skb_load_bytes_proto = {
.func = bpf_skb_load_bytes,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_PTR_TO_UNINIT_MEM,
.arg4_type = ARG_CONST_SIZE,
};
BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len)
{
/* Idea is the following: should the needed direct read/write
* test fail during runtime, we can pull in more data and redo
* again, since implicitly, we invalidate previous checks here.
*
* Or, since we know how much we need to make read/writeable,
* this can be done once at the program beginning for direct
* access case. By this we overcome limitations of only current
* headroom being accessible.
*/
return bpf_try_make_writable(skb, len ? : skb_headlen(skb));
}
static const struct bpf_func_proto bpf_skb_pull_data_proto = {
.func = bpf_skb_pull_data,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset,
u64, from, u64, to, u64, flags)
{
__sum16 *ptr;
if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK)))
return -EINVAL;
if (unlikely(offset > 0xffff || offset & 1))
return -EFAULT;
if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
return -EFAULT;
ptr = (__sum16 *)(skb->data + offset);
switch (flags & BPF_F_HDR_FIELD_MASK) {
case 0:
if (unlikely(from != 0))
return -EINVAL;
csum_replace_by_diff(ptr, to);
break;
case 2:
csum_replace2(ptr, from, to);
break;
case 4:
csum_replace4(ptr, from, to);
break;
default:
return -EINVAL;
}
return 0;
}
static const struct bpf_func_proto bpf_l3_csum_replace_proto = {
.func = bpf_l3_csum_replace,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_ANYTHING,
.arg5_type = ARG_ANYTHING,
};
BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset,
u64, from, u64, to, u64, flags)
{
bool is_pseudo = flags & BPF_F_PSEUDO_HDR;
bool is_mmzero = flags & BPF_F_MARK_MANGLED_0;
bool do_mforce = flags & BPF_F_MARK_ENFORCE;
__sum16 *ptr;
if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE |
BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK)))
return -EINVAL;
if (unlikely(offset > 0xffff || offset & 1))
return -EFAULT;
if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
return -EFAULT;
ptr = (__sum16 *)(skb->data + offset);
if (is_mmzero && !do_mforce && !*ptr)
return 0;
switch (flags & BPF_F_HDR_FIELD_MASK) {
case 0:
if (unlikely(from != 0))
return -EINVAL;
inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo);
break;
case 2:
inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo);
break;
case 4:
inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo);
break;
default:
return -EINVAL;
}
if (is_mmzero && !*ptr)
*ptr = CSUM_MANGLED_0;
return 0;
}
static const struct bpf_func_proto bpf_l4_csum_replace_proto = {
.func = bpf_l4_csum_replace,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_ANYTHING,
.arg5_type = ARG_ANYTHING,
};
BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size,
__be32 *, to, u32, to_size, __wsum, seed)
{
struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp);
u32 diff_size = from_size + to_size;
int i, j = 0;
/* This is quite flexible, some examples:
*
* from_size == 0, to_size > 0, seed := csum --> pushing data
* from_size > 0, to_size == 0, seed := csum --> pulling data
* from_size > 0, to_size > 0, seed := 0 --> diffing data
*
* Even for diffing, from_size and to_size don't need to be equal.
*/
if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) ||
diff_size > sizeof(sp->diff)))
return -EINVAL;
for (i = 0; i < from_size / sizeof(__be32); i++, j++)
sp->diff[j] = ~from[i];
for (i = 0; i < to_size / sizeof(__be32); i++, j++)
sp->diff[j] = to[i];
return csum_partial(sp->diff, diff_size, seed);
}
static const struct bpf_func_proto bpf_csum_diff_proto = {
.func = bpf_csum_diff,
.gpl_only = false,
.pkt_access = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_MEM_OR_NULL,
.arg2_type = ARG_CONST_SIZE_OR_ZERO,
.arg3_type = ARG_PTR_TO_MEM_OR_NULL,
.arg4_type = ARG_CONST_SIZE_OR_ZERO,
.arg5_type = ARG_ANYTHING,
};
BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum)
{
/* The interface is to be used in combination with bpf_csum_diff()
* for direct packet writes. csum rotation for alignment as well
* as emulating csum_sub() can be done from the eBPF program.
*/
if (skb->ip_summed == CHECKSUM_COMPLETE)
return (skb->csum = csum_add(skb->csum, csum));
return -ENOTSUPP;
}
static const struct bpf_func_proto bpf_csum_update_proto = {
.func = bpf_csum_update,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb)
{
return dev_forward_skb(dev, skb);
}
static inline int __bpf_rx_skb_no_mac(struct net_device *dev,
struct sk_buff *skb)
{
int ret = ____dev_forward_skb(dev, skb);
if (likely(!ret)) {
skb->dev = dev;
ret = netif_rx(skb);
}
return ret;
}
static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
{
int ret;
if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) {
net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
kfree_skb(skb);
return -ENETDOWN;
}
skb->dev = dev;
__this_cpu_inc(xmit_recursion);
ret = dev_queue_xmit(skb);
__this_cpu_dec(xmit_recursion);
return ret;
}
static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev,
u32 flags)
{
/* skb->mac_len is not set on normal egress */
unsigned int mlen = skb->network_header - skb->mac_header;
__skb_pull(skb, mlen);
/* At ingress, the mac header has already been pulled once.
* At egress, skb_pospull_rcsum has to be done in case that
* the skb is originated from ingress (i.e. a forwarded skb)
* to ensure that rcsum starts at net header.
*/
if (!skb_at_tc_ingress(skb))
skb_postpull_rcsum(skb, skb_mac_header(skb), mlen);
skb_pop_mac_header(skb);
skb_reset_mac_len(skb);
return flags & BPF_F_INGRESS ?
__bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb);
}
static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev,
u32 flags)
{
/* Verify that a link layer header is carried */
if (unlikely(skb->mac_header >= skb->network_header)) {
kfree_skb(skb);
return -ERANGE;
}
bpf_push_mac_rcsum(skb);
return flags & BPF_F_INGRESS ?
__bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
}
static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev,
u32 flags)
{
if (dev_is_mac_header_xmit(dev))
return __bpf_redirect_common(skb, dev, flags);
else
return __bpf_redirect_no_mac(skb, dev, flags);
}
BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
{
struct net_device *dev;
struct sk_buff *clone;
int ret;
if (unlikely(flags & ~(BPF_F_INGRESS)))
return -EINVAL;
dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex);
if (unlikely(!dev))
return -EINVAL;
clone = skb_clone(skb, GFP_ATOMIC);
if (unlikely(!clone))
return -ENOMEM;
/* For direct write, we need to keep the invariant that the skbs
* we're dealing with need to be uncloned. Should uncloning fail
* here, we need to free the just generated clone to unclone once
* again.
*/
ret = bpf_try_make_head_writable(skb);
if (unlikely(ret)) {
kfree_skb(clone);
return -ENOMEM;
}
return __bpf_redirect(clone, dev, flags);
}
static const struct bpf_func_proto bpf_clone_redirect_proto = {
.func = bpf_clone_redirect,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
};
struct redirect_info {
u32 ifindex;
u32 flags;
struct bpf_map *map;
struct bpf_map *map_to_flush;
unsigned long map_owner;
};
static DEFINE_PER_CPU(struct redirect_info, redirect_info);
BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags)
{
struct redirect_info *ri = this_cpu_ptr(&redirect_info);
if (unlikely(flags & ~(BPF_F_INGRESS)))
return TC_ACT_SHOT;
ri->ifindex = ifindex;
ri->flags = flags;
return TC_ACT_REDIRECT;
}
int skb_do_redirect(struct sk_buff *skb)
{
struct redirect_info *ri = this_cpu_ptr(&redirect_info);
struct net_device *dev;
dev = dev_get_by_index_rcu(dev_net(skb->dev), ri->ifindex);
ri->ifindex = 0;
if (unlikely(!dev)) {
kfree_skb(skb);
return -EINVAL;
}
return __bpf_redirect(skb, dev, ri->flags);
}
static const struct bpf_func_proto bpf_redirect_proto = {
.func = bpf_redirect,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_ANYTHING,
.arg2_type = ARG_ANYTHING,
};
BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb,
struct bpf_map *, map, u32, key, u64, flags)
{
struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
/* If user passes invalid input drop the packet. */
if (unlikely(flags))
return SK_DROP;
tcb->bpf.key = key;
tcb->bpf.flags = flags;
tcb->bpf.map = map;
return SK_PASS;
}
struct sock *do_sk_redirect_map(struct sk_buff *skb)
{
struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
struct sock *sk = NULL;
if (tcb->bpf.map) {
sk = __sock_map_lookup_elem(tcb->bpf.map, tcb->bpf.key);
tcb->bpf.key = 0;
tcb->bpf.map = NULL;
}
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_PTR_TO_CTX,
.arg2_type = ARG_CONST_MAP_PTR,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_ANYTHING,
};
BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb)
{
return task_get_classid(skb);
}
static const struct bpf_func_proto bpf_get_cgroup_classid_proto = {
.func = bpf_get_cgroup_classid,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb)
{
return dst_tclassid(skb);
}
static const struct bpf_func_proto bpf_get_route_realm_proto = {
.func = bpf_get_route_realm,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb)
{
/* If skb_clear_hash() was called due to mangling, we can
* trigger SW recalculation here. Later access to hash
* can then use the inline skb->hash via context directly
* instead of calling this helper again.
*/
return skb_get_hash(skb);
}
static const struct bpf_func_proto bpf_get_hash_recalc_proto = {
.func = bpf_get_hash_recalc,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb)
{
/* After all direct packet write, this can be used once for
* triggering a lazy recalc on next skb_get_hash() invocation.
*/
skb_clear_hash(skb);
return 0;
}
static const struct bpf_func_proto bpf_set_hash_invalid_proto = {
.func = bpf_set_hash_invalid,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash)
{
/* Set user specified hash as L4(+), so that it gets returned
* on skb_get_hash() call unless BPF prog later on triggers a
* skb_clear_hash().
*/
__skb_set_sw_hash(skb, hash, true);
return 0;
}
static const struct bpf_func_proto bpf_set_hash_proto = {
.func = bpf_set_hash,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto,
u16, vlan_tci)
{
int ret;
if (unlikely(vlan_proto != htons(ETH_P_8021Q) &&
vlan_proto != htons(ETH_P_8021AD)))
vlan_proto = htons(ETH_P_8021Q);
bpf_push_mac_rcsum(skb);
ret = skb_vlan_push(skb, vlan_proto, vlan_tci);
bpf_pull_mac_rcsum(skb);
bpf_compute_data_pointers(skb);
return ret;
}
const struct bpf_func_proto bpf_skb_vlan_push_proto = {
.func = bpf_skb_vlan_push,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
};
EXPORT_SYMBOL_GPL(bpf_skb_vlan_push_proto);
BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb)
{
int ret;
bpf_push_mac_rcsum(skb);
ret = skb_vlan_pop(skb);
bpf_pull_mac_rcsum(skb);
bpf_compute_data_pointers(skb);
return ret;
}
const struct bpf_func_proto bpf_skb_vlan_pop_proto = {
.func = bpf_skb_vlan_pop,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
EXPORT_SYMBOL_GPL(bpf_skb_vlan_pop_proto);
static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len)
{
/* Caller already did skb_cow() with len as headroom,
* so no need to do it here.
*/
skb_push(skb, len);
memmove(skb->data, skb->data + len, off);
memset(skb->data + off, 0, len);
/* No skb_postpush_rcsum(skb, skb->data + off, len)
* needed here as it does not change the skb->csum
* result for checksum complete when summing over
* zeroed blocks.
*/
return 0;
}
static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len)
{
/* skb_ensure_writable() is not needed here, as we're
* already working on an uncloned skb.
*/
if (unlikely(!pskb_may_pull(skb, off + len)))
return -ENOMEM;
skb_postpull_rcsum(skb, skb->data + off, len);
memmove(skb->data + len, skb->data, off);
__skb_pull(skb, len);
return 0;
}
static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len)
{
bool trans_same = skb->transport_header == skb->network_header;
int ret;
/* There's no need for __skb_push()/__skb_pull() pair to
* get to the start of the mac header as we're guaranteed
* to always start from here under eBPF.
*/
ret = bpf_skb_generic_push(skb, off, len);
if (likely(!ret)) {
skb->mac_header -= len;
skb->network_header -= len;
if (trans_same)
skb->transport_header = skb->network_header;
}
return ret;
}
static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len)
{
bool trans_same = skb->transport_header == skb->network_header;
int ret;
/* Same here, __skb_push()/__skb_pull() pair not needed. */
ret = bpf_skb_generic_pop(skb, off, len);
if (likely(!ret)) {
skb->mac_header += len;
skb->network_header += len;
if (trans_same)
skb->transport_header = skb->network_header;
}
return ret;
}
static int bpf_skb_proto_4_to_6(struct sk_buff *skb)
{
const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
u32 off = skb_mac_header_len(skb);
int ret;
ret = skb_cow(skb, len_diff);
if (unlikely(ret < 0))
return ret;
ret = bpf_skb_net_hdr_push(skb, off, len_diff);
if (unlikely(ret < 0))
return ret;
if (skb_is_gso(skb)) {
/* 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;
skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV6;
}
/* Due to IPv6 header, MSS needs to be downgraded. */
skb_shinfo(skb)->gso_size -= len_diff;
/* Header must be checked, and gso_segs recomputed. */
skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
skb_shinfo(skb)->gso_segs = 0;
}
skb->protocol = htons(ETH_P_IPV6);
skb_clear_hash(skb);
return 0;
}
static int bpf_skb_proto_6_to_4(struct sk_buff *skb)
{
const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
u32 off = skb_mac_header_len(skb);
int ret;
ret = skb_unclone(skb, GFP_ATOMIC);
if (unlikely(ret < 0))
return ret;
ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
if (unlikely(ret < 0))
return ret;
if (skb_is_gso(skb)) {
/* 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;
skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV4;
}
/* Due to IPv4 header, MSS can be upgraded. */
skb_shinfo(skb)->gso_size += len_diff;
/* Header must be checked, and gso_segs recomputed. */
skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
skb_shinfo(skb)->gso_segs = 0;
}
skb->protocol = htons(ETH_P_IP);
skb_clear_hash(skb);
return 0;
}
static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto)
{
__be16 from_proto = skb->protocol;
if (from_proto == htons(ETH_P_IP) &&
to_proto == htons(ETH_P_IPV6))
return bpf_skb_proto_4_to_6(skb);
if (from_proto == htons(ETH_P_IPV6) &&
to_proto == htons(ETH_P_IP))
return bpf_skb_proto_6_to_4(skb);
return -ENOTSUPP;
}
BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto,
u64, flags)
{
int ret;
if (unlikely(flags))
return -EINVAL;
/* General idea is that this helper does the basic groundwork
* needed for changing the protocol, and eBPF program fills the
* rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
* and other helpers, rather than passing a raw buffer here.
*
* The rationale is to keep this minimal and without a need to
* deal with raw packet data. F.e. even if we would pass buffers
* here, the program still needs to call the bpf_lX_csum_replace()
* helpers anyway. Plus, this way we keep also separation of
* concerns, since f.e. bpf_skb_store_bytes() should only take
* care of stores.
*
* Currently, additional options and extension header space are
* not supported, but flags register is reserved so we can adapt
* that. For offloads, we mark packet as dodgy, so that headers
* need to be verified first.
*/
ret = bpf_skb_proto_xlat(skb, proto);
bpf_compute_data_pointers(skb);
return ret;
}
static const struct bpf_func_proto bpf_skb_change_proto_proto = {
.func = bpf_skb_change_proto,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
};
BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type)
{
/* We only allow a restricted subset to be changed for now. */
if (unlikely(!skb_pkt_type_ok(skb->pkt_type) ||
!skb_pkt_type_ok(pkt_type)))
return -EINVAL;
skb->pkt_type = pkt_type;
return 0;
}
static const struct bpf_func_proto bpf_skb_change_type_proto = {
.func = bpf_skb_change_type,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
static u32 bpf_skb_net_base_len(const struct sk_buff *skb)
{
switch (skb->protocol) {
case htons(ETH_P_IP):
return sizeof(struct iphdr);
case htons(ETH_P_IPV6):
return sizeof(struct ipv6hdr);
default:
return ~0U;
}
}
static int bpf_skb_net_grow(struct sk_buff *skb, u32 len_diff)
{
u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb);
int ret;
ret = skb_cow(skb, len_diff);
if (unlikely(ret < 0))
return ret;
ret = bpf_skb_net_hdr_push(skb, off, len_diff);
if (unlikely(ret < 0))
return ret;
if (skb_is_gso(skb)) {
/* Due to header grow, MSS needs to be downgraded. */
skb_shinfo(skb)->gso_size -= len_diff;
/* Header must be checked, and gso_segs recomputed. */
skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
skb_shinfo(skb)->gso_segs = 0;
}
return 0;
}
static int bpf_skb_net_shrink(struct sk_buff *skb, u32 len_diff)
{
u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb);
int ret;
ret = skb_unclone(skb, GFP_ATOMIC);
if (unlikely(ret < 0))
return ret;
ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
if (unlikely(ret < 0))
return ret;
if (skb_is_gso(skb)) {
/* Due to header shrink, MSS can be upgraded. */
skb_shinfo(skb)->gso_size += len_diff;
/* Header must be checked, and gso_segs recomputed. */
skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
skb_shinfo(skb)->gso_segs = 0;
}
return 0;
}
static u32 __bpf_skb_max_len(const struct sk_buff *skb)
{
return skb->dev->mtu + skb->dev->hard_header_len;
}
static int bpf_skb_adjust_net(struct sk_buff *skb, s32 len_diff)
{
bool trans_same = skb->transport_header == skb->network_header;
u32 len_cur, len_diff_abs = abs(len_diff);
u32 len_min = bpf_skb_net_base_len(skb);
u32 len_max = __bpf_skb_max_len(skb);
__be16 proto = skb->protocol;
bool shrink = len_diff < 0;
int ret;
if (unlikely(len_diff_abs > 0xfffU))
return -EFAULT;
if (unlikely(proto != htons(ETH_P_IP) &&
proto != htons(ETH_P_IPV6)))
return -ENOTSUPP;
len_cur = skb->len - skb_network_offset(skb);
if (skb_transport_header_was_set(skb) && !trans_same)
len_cur = skb_network_header_len(skb);
if ((shrink && (len_diff_abs >= len_cur ||
len_cur - len_diff_abs < len_min)) ||
(!shrink && (skb->len + len_diff_abs > len_max &&
!skb_is_gso(skb))))
return -ENOTSUPP;
ret = shrink ? bpf_skb_net_shrink(skb, len_diff_abs) :
bpf_skb_net_grow(skb, len_diff_abs);
bpf_compute_data_pointers(skb);
return ret;
}
BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
u32, mode, u64, flags)
{
if (unlikely(flags))
return -EINVAL;
if (likely(mode == BPF_ADJ_ROOM_NET))
return bpf_skb_adjust_net(skb, len_diff);
return -ENOTSUPP;
}
static const struct bpf_func_proto bpf_skb_adjust_room_proto = {
.func = bpf_skb_adjust_room,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_ANYTHING,
};
static u32 __bpf_skb_min_len(const struct sk_buff *skb)
{
u32 min_len = skb_network_offset(skb);
if (skb_transport_header_was_set(skb))
min_len = skb_transport_offset(skb);
if (skb->ip_summed == CHECKSUM_PARTIAL)
min_len = skb_checksum_start_offset(skb) +
skb->csum_offset + sizeof(__sum16);
return min_len;
}
static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len)
{
unsigned int old_len = skb->len;
int ret;
ret = __skb_grow_rcsum(skb, new_len);
if (!ret)
memset(skb->data + old_len, 0, new_len - old_len);
return ret;
}
static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len)
{
return __skb_trim_rcsum(skb, new_len);
}
BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len,
u64, flags)
{
u32 max_len = __bpf_skb_max_len(skb);
u32 min_len = __bpf_skb_min_len(skb);
int ret;
if (unlikely(flags || new_len > max_len || new_len < min_len))
return -EINVAL;
if (skb->encapsulation)
return -ENOTSUPP;
/* The basic idea of this helper is that it's performing the
* needed work to either grow or trim an skb, and eBPF program
* rewrites the rest via helpers like bpf_skb_store_bytes(),
* bpf_lX_csum_replace() and others rather than passing a raw
* buffer here. This one is a slow path helper and intended
* for replies with control messages.
*
* Like in bpf_skb_change_proto(), we want to keep this rather
* minimal and without protocol specifics so that we are able
* to separate concerns as in bpf_skb_store_bytes() should only
* be the one responsible for writing buffers.
*
* It's really expected to be a slow path operation here for
* control message replies, so we're implicitly linearizing,
* uncloning and drop offloads from the skb by this.
*/
ret = __bpf_try_make_writable(skb, skb->len);
if (!ret) {
if (new_len > skb->len)
ret = bpf_skb_grow_rcsum(skb, new_len);
else if (new_len < skb->len)
ret = bpf_skb_trim_rcsum(skb, new_len);
if (!ret && skb_is_gso(skb))
skb_gso_reset(skb);
}
bpf_compute_data_pointers(skb);
return ret;
}
static const struct bpf_func_proto bpf_skb_change_tail_proto = {
.func = bpf_skb_change_tail,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
};
BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room,
u64, flags)
{
u32 max_len = __bpf_skb_max_len(skb);
u32 new_len = skb->len + head_room;
int ret;
if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) ||
new_len < skb->len))
return -EINVAL;
ret = skb_cow(skb, head_room);
if (likely(!ret)) {
/* Idea for this helper is that we currently only
* allow to expand on mac header. This means that
* skb->protocol network header, etc, stay as is.
* Compared to bpf_skb_change_tail(), we're more
* flexible due to not needing to linearize or
* reset GSO. Intention for this helper is to be
* used by an L3 skb that needs to push mac header
* for redirection into L2 device.
*/
__skb_push(skb, head_room);
memset(skb->data, 0, head_room);
skb_reset_mac_header(skb);
}
bpf_compute_data_pointers(skb);
return 0;
}
static const struct bpf_func_proto bpf_skb_change_head_proto = {
.func = bpf_skb_change_head,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
};
static unsigned long xdp_get_metalen(const struct xdp_buff *xdp)
{
return xdp_data_meta_unsupported(xdp) ? 0 :
xdp->data - xdp->data_meta;
}
BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset)
{
unsigned long metalen = xdp_get_metalen(xdp);
void *data_start = xdp->data_hard_start + metalen;
void *data = xdp->data + offset;
if (unlikely(data < data_start ||
data > xdp->data_end - ETH_HLEN))
return -EINVAL;
if (metalen)
memmove(xdp->data_meta + offset,
xdp->data_meta, metalen);
xdp->data_meta += offset;
xdp->data = data;
return 0;
}
static const struct bpf_func_proto bpf_xdp_adjust_head_proto = {
.func = bpf_xdp_adjust_head,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset)
{
void *meta = xdp->data_meta + offset;
unsigned long metalen = xdp->data - meta;
if (xdp_data_meta_unsupported(xdp))
return -ENOTSUPP;
if (unlikely(meta < xdp->data_hard_start ||
meta > xdp->data))
return -EINVAL;
if (unlikely((metalen & (sizeof(__u32) - 1)) ||
(metalen > 32)))
return -EACCES;
xdp->data_meta = meta;
return 0;
}
static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = {
.func = bpf_xdp_adjust_meta,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.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;
dev->netdev_ops->ndo_xdp_flush(dev);
return 0;
}
static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd,
struct bpf_map *map,
struct xdp_buff *xdp,
u32 index)
{
int err;
if (map->map_type == BPF_MAP_TYPE_DEVMAP) {
struct net_device *dev = fwd;
if (!dev->netdev_ops->ndo_xdp_xmit)
return -EOPNOTSUPP;
err = dev->netdev_ops->ndo_xdp_xmit(dev, xdp);
if (err)
return err;
__dev_map_insert_ctx(map, index);
} else if (map->map_type == BPF_MAP_TYPE_CPUMAP) {
struct bpf_cpu_map_entry *rcpu = fwd;
err = cpu_map_enqueue(rcpu, xdp, dev_rx);
if (err)
return err;
__cpu_map_insert_ctx(map, index);
}
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) {
switch (map->map_type) {
case BPF_MAP_TYPE_DEVMAP:
__dev_map_flush(map);
break;
case BPF_MAP_TYPE_CPUMAP:
__cpu_map_flush(map);
break;
default:
break;
}
}
}
EXPORT_SYMBOL_GPL(xdp_do_flush_map);
static void *__xdp_map_lookup_elem(struct bpf_map *map, u32 index)
{
switch (map->map_type) {
case BPF_MAP_TYPE_DEVMAP:
return __dev_map_lookup_elem(map, index);
case BPF_MAP_TYPE_CPUMAP:
return __cpu_map_lookup_elem(map, index);
default:
return NULL;
}
}
static inline bool xdp_map_invalid(const struct bpf_prog *xdp_prog,
unsigned long aux)
{
return (unsigned long)xdp_prog->aux != aux;
}
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);
unsigned long map_owner = ri->map_owner;
struct bpf_map *map = ri->map;
u32 index = ri->ifindex;
void *fwd = NULL;
int err;
ri->ifindex = 0;
ri->map = NULL;
ri->map_owner = 0;
if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) {
err = -EFAULT;
map = NULL;
goto err;
}
fwd = __xdp_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_map(dev, 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);
static int __xdp_generic_ok_fwd_dev(struct sk_buff *skb, struct net_device *fwd)
{
unsigned int len;
if (unlikely(!(fwd->flags & IFF_UP)))
return -ENETDOWN;
len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN;
if (skb->len > len)
return -EMSGSIZE;
return 0;
}
int xdp_do_generic_redirect_map(struct net_device *dev, struct sk_buff *skb,
struct bpf_prog *xdp_prog)
{
struct redirect_info *ri = this_cpu_ptr(&redirect_info);
unsigned long map_owner = ri->map_owner;
struct bpf_map *map = ri->map;
struct net_device *fwd = NULL;
u32 index = ri->ifindex;
int err = 0;
ri->ifindex = 0;
ri->map = NULL;
ri->map_owner = 0;
if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) {
err = -EFAULT;
map = NULL;
goto err;
}
fwd = __xdp_map_lookup_elem(map, index);
if (unlikely(!fwd)) {
err = -EINVAL;
goto err;
}
if (map->map_type == BPF_MAP_TYPE_DEVMAP) {
if (unlikely((err = __xdp_generic_ok_fwd_dev(skb, fwd))))
goto err;
skb->dev = fwd;
} else {
/* TODO: Handle BPF_MAP_TYPE_CPUMAP */
err = -EBADRQC;
goto err;
}
_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_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;
int err = 0;
if (ri->map)
return xdp_do_generic_redirect_map(dev, skb, xdp_prog);
ri->ifindex = 0;
fwd = dev_get_by_index_rcu(dev_net(dev), index);
if (unlikely(!fwd)) {
err = -EINVAL;
goto err;
}
if (unlikely((err = __xdp_generic_ok_fwd_dev(skb, fwd))))
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;
ri->map = NULL;
ri->map_owner = 0;
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_4(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, u64, flags,
unsigned long, map_owner)
{
struct redirect_info *ri = this_cpu_ptr(&redirect_info);
if (unlikely(flags))
return XDP_ABORTED;
ri->ifindex = ifindex;
ri->flags = flags;
ri->map = map;
ri->map_owner = map_owner;
return XDP_REDIRECT;
}
/* Note, arg4 is hidden from users and populated by the verifier
* with the right pointer.
*/
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 ||
func == bpf_skb_vlan_pop ||
func == bpf_skb_store_bytes ||
func == bpf_skb_change_proto ||
func == bpf_skb_change_head ||
func == bpf_skb_change_tail ||
func == bpf_skb_adjust_room ||
func == bpf_skb_pull_data ||
func == bpf_clone_redirect ||
func == bpf_l3_csum_replace ||
func == bpf_l4_csum_replace ||
func == bpf_xdp_adjust_head ||
func == bpf_xdp_adjust_meta)
return true;
return false;
}
static unsigned long bpf_skb_copy(void *dst_buff, const void *skb,
unsigned long off, unsigned long len)
{
void *ptr = skb_header_pointer(skb, off, len, dst_buff);
if (unlikely(!ptr))
return len;
if (ptr != dst_buff)
memcpy(dst_buff, ptr, len);
return 0;
}
BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map,
u64, flags, void *, meta, u64, meta_size)
{
u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
return -EINVAL;
if (unlikely(skb_size > skb->len))
return -EFAULT;
return bpf_event_output(map, flags, meta, meta_size, skb, skb_size,
bpf_skb_copy);
}
static const struct bpf_func_proto bpf_skb_event_output_proto = {
.func = bpf_skb_event_output,
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_CONST_MAP_PTR,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_PTR_TO_MEM,
.arg5_type = ARG_CONST_SIZE,
};
static unsigned short bpf_tunnel_key_af(u64 flags)
{
return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET;
}
BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to,
u32, size, u64, flags)
{
const struct ip_tunnel_info *info = skb_tunnel_info(skb);
u8 compat[sizeof(struct bpf_tunnel_key)];
void *to_orig = to;
int err;
if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6)))) {
err = -EINVAL;
goto err_clear;
}
if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) {
err = -EPROTO;
goto err_clear;
}
if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
err = -EINVAL;
switch (size) {
case offsetof(struct bpf_tunnel_key, tunnel_label):
case offsetof(struct bpf_tunnel_key, tunnel_ext):
goto set_compat;
case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
/* Fixup deprecated structure layouts here, so we have
* a common path later on.
*/
if (ip_tunnel_info_af(info) != AF_INET)
goto err_clear;
set_compat:
to = (struct bpf_tunnel_key *)compat;
break;
default:
goto err_clear;
}
}
to->tunnel_id = be64_to_cpu(info->key.tun_id);
to->tunnel_tos = info->key.tos;
to->tunnel_ttl = info->key.ttl;
if (flags & BPF_F_TUNINFO_IPV6) {
memcpy(to->remote_ipv6, &info->key.u.ipv6.src,
sizeof(to->remote_ipv6));
to->tunnel_label = be32_to_cpu(info->key.label);
} else {
to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src);
}
if (unlikely(size != sizeof(struct bpf_tunnel_key)))
memcpy(to_orig, to, size);
return 0;
err_clear:
memset(to_orig, 0, size);
return err;
}
static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = {
.func = bpf_skb_get_tunnel_key,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_PTR_TO_UNINIT_MEM,
.arg3_type = ARG_CONST_SIZE,
.arg4_type = ARG_ANYTHING,
};
BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size)
{
const struct ip_tunnel_info *info = skb_tunnel_info(skb);
int err;
if (unlikely(!info ||
!(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) {
err = -ENOENT;
goto err_clear;
}
if (unlikely(size < info->options_len)) {
err = -ENOMEM;
goto err_clear;
}
ip_tunnel_info_opts_get(to, info);
if (size > info->options_len)
memset(to + info->options_len, 0, size - info->options_len);
return info->options_len;
err_clear:
memset(to, 0, size);
return err;
}
static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = {
.func = bpf_skb_get_tunnel_opt,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_PTR_TO_UNINIT_MEM,
.arg3_type = ARG_CONST_SIZE,
};
static struct metadata_dst __percpu *md_dst;
BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb,
const struct bpf_tunnel_key *, from, u32, size, u64, flags)
{
struct metadata_dst *md = this_cpu_ptr(md_dst);
u8 compat[sizeof(struct bpf_tunnel_key)];
struct ip_tunnel_info *info;
if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX |
BPF_F_DONT_FRAGMENT)))
return -EINVAL;
if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
switch (size) {
case offsetof(struct bpf_tunnel_key, tunnel_label):
case offsetof(struct bpf_tunnel_key, tunnel_ext):
case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
/* Fixup deprecated structure layouts here, so we have
* a common path later on.
*/
memcpy(compat, from, size);
memset(compat + size, 0, sizeof(compat) - size);
from = (const struct bpf_tunnel_key *) compat;
break;
default:
return -EINVAL;
}
}
if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) ||
from->tunnel_ext))
return -EINVAL;
skb_dst_drop(skb);
dst_hold((struct dst_entry *) md);
skb_dst_set(skb, (struct dst_entry *) md);
info = &md->u.tun_info;
info->mode = IP_TUNNEL_INFO_TX;
info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE;
if (flags & BPF_F_DONT_FRAGMENT)
info->key.tun_flags |= TUNNEL_DONT_FRAGMENT;
info->key.tun_id = cpu_to_be64(from->tunnel_id);
info->key.tos = from->tunnel_tos;
info->key.ttl = from->tunnel_ttl;
if (flags & BPF_F_TUNINFO_IPV6) {
info->mode |= IP_TUNNEL_INFO_IPV6;
memcpy(&info->key.u.ipv6.dst, from->remote_ipv6,
sizeof(from->remote_ipv6));
info->key.label = cpu_to_be32(from->tunnel_label) &
IPV6_FLOWLABEL_MASK;
} else {
info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4);
if (flags & BPF_F_ZERO_CSUM_TX)
info->key.tun_flags &= ~TUNNEL_CSUM;
}
return 0;
}
static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = {
.func = bpf_skb_set_tunnel_key,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_PTR_TO_MEM,
.arg3_type = ARG_CONST_SIZE,
.arg4_type = ARG_ANYTHING,
};
BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb,
const u8 *, from, u32, size)
{
struct ip_tunnel_info *info = skb_tunnel_info(skb);
const struct metadata_dst *md = this_cpu_ptr(md_dst);
if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1))))
return -EINVAL;
if (unlikely(size > IP_TUNNEL_OPTS_MAX))
return -ENOMEM;
ip_tunnel_info_opts_set(info, from, size);
return 0;
}
static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = {
.func = bpf_skb_set_tunnel_opt,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_PTR_TO_MEM,
.arg3_type = ARG_CONST_SIZE,
};
static const struct bpf_func_proto *
bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)
{
if (!md_dst) {
struct metadata_dst __percpu *tmp;
tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX,
METADATA_IP_TUNNEL,
GFP_KERNEL);
if (!tmp)
return NULL;
if (cmpxchg(&md_dst, NULL, tmp))
metadata_dst_free_percpu(tmp);
}
switch (which) {
case BPF_FUNC_skb_set_tunnel_key:
return &bpf_skb_set_tunnel_key_proto;
case BPF_FUNC_skb_set_tunnel_opt:
return &bpf_skb_set_tunnel_opt_proto;
default:
return NULL;
}
}
BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map,
u32, idx)
{
struct bpf_array *array = container_of(map, struct bpf_array, map);
struct cgroup *cgrp;
struct sock *sk;
sk = skb_to_full_sk(skb);
if (!sk || !sk_fullsock(sk))
return -ENOENT;
if (unlikely(idx >= array->map.max_entries))
return -E2BIG;
cgrp = READ_ONCE(array->ptrs[idx]);
if (unlikely(!cgrp))
return -EAGAIN;
return sk_under_cgroup_hierarchy(sk, cgrp);
}
static const struct bpf_func_proto bpf_skb_under_cgroup_proto = {
.func = bpf_skb_under_cgroup,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_CONST_MAP_PTR,
.arg3_type = ARG_ANYTHING,
};
static unsigned long bpf_xdp_copy(void *dst_buff, const void *src_buff,
unsigned long off, unsigned long len)
{
memcpy(dst_buff, src_buff + off, len);
return 0;
}
BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map,
u64, flags, void *, meta, u64, meta_size)
{
u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
return -EINVAL;
if (unlikely(xdp_size > (unsigned long)(xdp->data_end - xdp->data)))
return -EFAULT;
return bpf_event_output(map, flags, meta, meta_size, xdp->data,
xdp_size, bpf_xdp_copy);
}
static const struct bpf_func_proto bpf_xdp_event_output_proto = {
.func = bpf_xdp_event_output,
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_CONST_MAP_PTR,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_PTR_TO_MEM,
.arg5_type = ARG_CONST_SIZE,
};
BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb)
{
return skb->sk ? sock_gen_cookie(skb->sk) : 0;
}
static const struct bpf_func_proto bpf_get_socket_cookie_proto = {
.func = bpf_get_socket_cookie,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
{
struct sock *sk = sk_to_full_sk(skb->sk);
kuid_t kuid;
if (!sk || !sk_fullsock(sk))
return overflowuid;
kuid = sock_net_uid(sock_net(sk), sk);
return from_kuid_munged(sock_net(sk)->user_ns, kuid);
}
static const struct bpf_func_proto bpf_get_socket_uid_proto = {
.func = bpf_get_socket_uid,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
int, level, int, optname, char *, optval, int, optlen)
{
struct sock *sk = bpf_sock->sk;
int ret = 0;
int val;
if (!sk_fullsock(sk))
return -EINVAL;
if (level == SOL_SOCKET) {
if (optlen != sizeof(int))
return -EINVAL;
val = *((int *)optval);
/* Only some socketops are supported */
switch (optname) {
case SO_RCVBUF:
sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
break;
case SO_SNDBUF:
sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
break;
case SO_MAX_PACING_RATE:
sk->sk_max_pacing_rate = val;
sk->sk_pacing_rate = min(sk->sk_pacing_rate,
sk->sk_max_pacing_rate);
break;
case SO_PRIORITY:
sk->sk_priority = val;
break;
case SO_RCVLOWAT:
if (val < 0)
val = INT_MAX;
sk->sk_rcvlowat = val ? : 1;
break;
case SO_MARK:
sk->sk_mark = val;
break;
default:
ret = -EINVAL;
}
#ifdef CONFIG_INET
} else if (level == SOL_TCP &&
sk->sk_prot->setsockopt == tcp_setsockopt) {
if (optname == TCP_CONGESTION) {
char name[TCP_CA_NAME_MAX];
bool reinit = bpf_sock->op > BPF_SOCK_OPS_NEEDS_ECN;
strncpy(name, optval, min_t(long, optlen,
TCP_CA_NAME_MAX-1));
name[TCP_CA_NAME_MAX-1] = 0;
ret = tcp_set_congestion_control(sk, name, false, reinit);
} else {
struct tcp_sock *tp = tcp_sk(sk);
if (optlen != sizeof(int))
return -EINVAL;
val = *((int *)optval);
/* Only some options are supported */
switch (optname) {
case TCP_BPF_IW:
if (val <= 0 || tp->data_segs_out > 0)
ret = -EINVAL;
else
tp->snd_cwnd = val;
break;
case TCP_BPF_SNDCWND_CLAMP:
if (val <= 0) {
ret = -EINVAL;
} else {
tp->snd_cwnd_clamp = val;
tp->snd_ssthresh = val;
}
break;
default:
ret = -EINVAL;
}
}
#endif
} else {
ret = -EINVAL;
}
return ret;
}
static const struct bpf_func_proto bpf_setsockopt_proto = {
.func = bpf_setsockopt,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_PTR_TO_MEM,
.arg5_type = ARG_CONST_SIZE,
};
BPF_CALL_5(bpf_getsockopt, struct bpf_sock_ops_kern *, bpf_sock,
int, level, int, optname, char *, optval, int, optlen)
{
struct sock *sk = bpf_sock->sk;
if (!sk_fullsock(sk))
goto err_clear;
#ifdef CONFIG_INET
if (level == SOL_TCP && sk->sk_prot->getsockopt == tcp_getsockopt) {
if (optname == TCP_CONGESTION) {
struct inet_connection_sock *icsk = inet_csk(sk);
if (!icsk->icsk_ca_ops || optlen <= 1)
goto err_clear;
strncpy(optval, icsk->icsk_ca_ops->name, optlen);
optval[optlen - 1] = 0;
} else {
goto err_clear;
}
} else {
goto err_clear;
}
return 0;
#endif
err_clear:
memset(optval, 0, optlen);
return -EINVAL;
}
static const struct bpf_func_proto bpf_getsockopt_proto = {
.func = bpf_getsockopt,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_PTR_TO_UNINIT_MEM,
.arg5_type = ARG_CONST_SIZE,
};
static const struct bpf_func_proto *
bpf_base_func_proto(enum bpf_func_id func_id)
{
switch (func_id) {
case BPF_FUNC_map_lookup_elem:
return &bpf_map_lookup_elem_proto;
case BPF_FUNC_map_update_elem:
return &bpf_map_update_elem_proto;
case BPF_FUNC_map_delete_elem:
return &bpf_map_delete_elem_proto;
case BPF_FUNC_get_prandom_u32:
return &bpf_get_prandom_u32_proto;
case BPF_FUNC_get_smp_processor_id:
return &bpf_get_raw_smp_processor_id_proto;
case BPF_FUNC_get_numa_node_id:
return &bpf_get_numa_node_id_proto;
case BPF_FUNC_tail_call:
return &bpf_tail_call_proto;
case BPF_FUNC_ktime_get_ns:
return &bpf_ktime_get_ns_proto;
case BPF_FUNC_trace_printk:
if (capable(CAP_SYS_ADMIN))
return bpf_get_trace_printk_proto();
default:
return NULL;
}
}
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) {
case BPF_FUNC_skb_load_bytes:
return &bpf_skb_load_bytes_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;
default:
return bpf_base_func_proto(func_id);
}
}
static const struct bpf_func_proto *
tc_cls_act_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_csum_diff:
return &bpf_csum_diff_proto;
case BPF_FUNC_csum_update:
return &bpf_csum_update_proto;
case BPF_FUNC_l3_csum_replace:
return &bpf_l3_csum_replace_proto;
case BPF_FUNC_l4_csum_replace:
return &bpf_l4_csum_replace_proto;
case BPF_FUNC_clone_redirect:
return &bpf_clone_redirect_proto;
case BPF_FUNC_get_cgroup_classid:
return &bpf_get_cgroup_classid_proto;
case BPF_FUNC_skb_vlan_push:
return &bpf_skb_vlan_push_proto;
case BPF_FUNC_skb_vlan_pop:
return &bpf_skb_vlan_pop_proto;
case BPF_FUNC_skb_change_proto:
return &bpf_skb_change_proto_proto;
case BPF_FUNC_skb_change_type:
return &bpf_skb_change_type_proto;
case BPF_FUNC_skb_adjust_room:
return &bpf_skb_adjust_room_proto;
case BPF_FUNC_skb_change_tail:
return &bpf_skb_change_tail_proto;
case BPF_FUNC_skb_get_tunnel_key:
return &bpf_skb_get_tunnel_key_proto;
case BPF_FUNC_skb_set_tunnel_key:
return bpf_get_skb_set_tunnel_proto(func_id);
case BPF_FUNC_skb_get_tunnel_opt:
return &bpf_skb_get_tunnel_opt_proto;
case BPF_FUNC_skb_set_tunnel_opt:
return bpf_get_skb_set_tunnel_proto(func_id);
case BPF_FUNC_redirect:
return &bpf_redirect_proto;
case BPF_FUNC_get_route_realm:
return &bpf_get_route_realm_proto;
case BPF_FUNC_get_hash_recalc:
return &bpf_get_hash_recalc_proto;
case BPF_FUNC_set_hash_invalid:
return &bpf_set_hash_invalid_proto;
case BPF_FUNC_set_hash:
return &bpf_set_hash_proto;
case BPF_FUNC_perf_event_output:
return &bpf_skb_event_output_proto;
case BPF_FUNC_get_smp_processor_id:
return &bpf_get_smp_processor_id_proto;
case BPF_FUNC_skb_under_cgroup:
return &bpf_skb_under_cgroup_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;
default:
return bpf_base_func_proto(func_id);
}
}
static const struct bpf_func_proto *
xdp_func_proto(enum bpf_func_id func_id)
{
switch (func_id) {
case BPF_FUNC_perf_event_output:
return &bpf_xdp_event_output_proto;
case BPF_FUNC_get_smp_processor_id:
return &bpf_get_smp_processor_id_proto;
case BPF_FUNC_xdp_adjust_head:
return &bpf_xdp_adjust_head_proto;
case BPF_FUNC_xdp_adjust_meta:
return &bpf_xdp_adjust_meta_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);
}
}
static const struct bpf_func_proto *
lwt_inout_func_proto(enum bpf_func_id func_id)
{
switch (func_id) {
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_csum_diff:
return &bpf_csum_diff_proto;
case BPF_FUNC_get_cgroup_classid:
return &bpf_get_cgroup_classid_proto;
case BPF_FUNC_get_route_realm:
return &bpf_get_route_realm_proto;
case BPF_FUNC_get_hash_recalc:
return &bpf_get_hash_recalc_proto;
case BPF_FUNC_perf_event_output:
return &bpf_skb_event_output_proto;
case BPF_FUNC_get_smp_processor_id:
return &bpf_get_smp_processor_id_proto;
case BPF_FUNC_skb_under_cgroup:
return &bpf_skb_under_cgroup_proto;
default:
return bpf_base_func_proto(func_id);
}
}
static const struct bpf_func_proto *
sock_ops_func_proto(enum bpf_func_id func_id)
{
switch (func_id) {
case BPF_FUNC_setsockopt:
return &bpf_setsockopt_proto;
case BPF_FUNC_getsockopt:
return &bpf_getsockopt_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);
}
}
static const struct bpf_func_proto *
lwt_xmit_func_proto(enum bpf_func_id func_id)
{
switch (func_id) {
case BPF_FUNC_skb_get_tunnel_key:
return &bpf_skb_get_tunnel_key_proto;
case BPF_FUNC_skb_set_tunnel_key:
return bpf_get_skb_set_tunnel_proto(func_id);
case BPF_FUNC_skb_get_tunnel_opt:
return &bpf_skb_get_tunnel_opt_proto;
case BPF_FUNC_skb_set_tunnel_opt:
return bpf_get_skb_set_tunnel_proto(func_id);
case BPF_FUNC_redirect:
return &bpf_redirect_proto;
case BPF_FUNC_clone_redirect:
return &bpf_clone_redirect_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_skb_store_bytes:
return &bpf_skb_store_bytes_proto;
case BPF_FUNC_csum_update:
return &bpf_csum_update_proto;
case BPF_FUNC_l3_csum_replace:
return &bpf_l3_csum_replace_proto;
case BPF_FUNC_l4_csum_replace:
return &bpf_l4_csum_replace_proto;
case BPF_FUNC_set_hash_invalid:
return &bpf_set_hash_invalid_proto;
default:
return lwt_inout_func_proto(func_id);
}
}
static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type,
struct bpf_insn_access_aux *info)
{
const int size_default = sizeof(__u32);
if (off < 0 || off >= sizeof(struct __sk_buff))
return false;
/* The verifier guarantees that size > 0. */
if (off % size != 0)
return false;
switch (off) {
case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
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_meta):
case bpf_ctx_range(struct __sk_buff, data_end):
if (size != size_default)
return false;
break;
default:
/* Only narrow read access allowed for now. */
if (type == BPF_WRITE) {
if (size != size_default)
return false;
} else {
bpf_ctx_record_field_size(info, size_default);
if (!bpf_ctx_narrow_access_ok(off, size, size_default))
return false;
}
}
return true;
}
static bool sk_filter_is_valid_access(int off, int size,
enum bpf_access_type type,
struct bpf_insn_access_aux *info)
{
switch (off) {
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_meta):
case bpf_ctx_range(struct __sk_buff, data_end):
case bpf_ctx_range_till(struct __sk_buff, family, local_port):
return false;
}
if (type == BPF_WRITE) {
switch (off) {
case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
break;
default:
return false;
}
}
return bpf_skb_is_valid_access(off, size, type, info);
}
static bool lwt_is_valid_access(int off, int size,
enum bpf_access_type type,
struct bpf_insn_access_aux *info)
{
switch (off) {
case bpf_ctx_range(struct __sk_buff, tc_classid):
case bpf_ctx_range_till(struct __sk_buff, family, local_port):
case bpf_ctx_range(struct __sk_buff, data_meta):
return false;
}
if (type == BPF_WRITE) {
switch (off) {
case bpf_ctx_range(struct __sk_buff, mark):
case bpf_ctx_range(struct __sk_buff, priority):
case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
break;
default:
return false;
}
}
switch (off) {
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 bool sock_filter_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 offsetof(struct bpf_sock, bound_dev_if):
case offsetof(struct bpf_sock, mark):
case offsetof(struct bpf_sock, priority):
break;
default:
return false;
}
}
if (off < 0 || off + size > sizeof(struct bpf_sock))
return false;
/* The verifier guarantees that size > 0. */
if (off % size != 0)
return false;
if (size != sizeof(__u32))
return false;
return true;
}
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;
if (!direct_write)
return 0;
/* if (!skb->cloned)
* goto start;
*
* (Fast-path, otherwise approximation that we might be
* a clone, do the rest in helper.)
*/
*insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET());
*insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK);
*insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7);
/* ret = bpf_skb_pull_data(skb, 0); */
*insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
*insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2);
*insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_skb_pull_data);
/* if (!ret)
* goto restore;
* return TC_ACT_SHOT;
*/
*insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2);
*insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict);
*insn++ = BPF_EXIT_INSN();
/* restore: */
*insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
/* start: */
*insn++ = prog->insnsi[0];
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)
{
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):
case bpf_ctx_range(struct __sk_buff, tc_classid):
case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
break;
default:
return false;
}
}
switch (off) {
case bpf_ctx_range(struct __sk_buff, data):
info->reg_type = PTR_TO_PACKET;
break;
case bpf_ctx_range(struct __sk_buff, data_meta):
info->reg_type = PTR_TO_PACKET_META;
break;
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);
}
static bool __is_valid_xdp_access(int off, int size)
{
if (off < 0 || off >= sizeof(struct xdp_md))
return false;
if (off % size != 0)
return false;
if (size != sizeof(__u32))
return false;
return true;
}
static bool xdp_is_valid_access(int off, int size,
enum bpf_access_type type,
struct bpf_insn_access_aux *info)
{
if (type == BPF_WRITE)
return false;
switch (off) {
case offsetof(struct xdp_md, data):
info->reg_type = PTR_TO_PACKET;
break;
case offsetof(struct xdp_md, data_meta):
info->reg_type = PTR_TO_PACKET_META;
break;
case offsetof(struct xdp_md, data_end):
info->reg_type = PTR_TO_PACKET_END;
break;
}
return __is_valid_xdp_access(off, size);
}
void bpf_warn_invalid_xdp_action(u32 act)
{
const u32 act_max = XDP_REDIRECT;
WARN_ONCE(1, "%s XDP return value %u, expect packet loss!\n",
act > act_max ? "Illegal" : "Driver unsupported",
act);
}
EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
static bool __is_valid_sock_ops_access(int off, int size)
{
if (off < 0 || off >= sizeof(struct bpf_sock_ops))
return false;
/* The verifier guarantees that size > 0. */
if (off % size != 0)
return false;
if (size != sizeof(__u32))
return false;
return true;
}
static bool sock_ops_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 offsetof(struct bpf_sock_ops, op) ...
offsetof(struct bpf_sock_ops, replylong[3]):
break;
default:
return false;
}
}
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)
{
switch (off) {
case bpf_ctx_range(struct __sk_buff, tc_classid):
case bpf_ctx_range(struct __sk_buff, data_meta):
return false;
}
if (type == BPF_WRITE) {
switch (off) {
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, mark):
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,
struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
int off;
switch (si->off) {
case offsetof(struct __sk_buff, len):
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, len, 4,
target_size));
break;
case offsetof(struct __sk_buff, protocol):
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, protocol, 2,
target_size));
break;
case offsetof(struct __sk_buff, vlan_proto):
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, vlan_proto, 2,
target_size));
break;
case offsetof(struct __sk_buff, priority):
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, priority, 4,
target_size));
else
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, priority, 4,
target_size));
break;
case offsetof(struct __sk_buff, ingress_ifindex):
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, skb_iif, 4,
target_size));
break;
case offsetof(struct __sk_buff, ifindex):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
si->dst_reg, si->src_reg,
offsetof(struct sk_buff, dev));
*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
bpf_target_off(struct net_device, ifindex, 4,
target_size));
break;
case offsetof(struct __sk_buff, hash):
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, hash, 4,
target_size));
break;
case offsetof(struct __sk_buff, mark):
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, mark, 4,
target_size));
else
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, mark, 4,
target_size));
break;
case offsetof(struct __sk_buff, pkt_type):
*target_size = 1;
*insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
PKT_TYPE_OFFSET());
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX);
#ifdef __BIG_ENDIAN_BITFIELD
*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5);
#endif
break;
case offsetof(struct __sk_buff, queue_mapping):
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, queue_mapping, 2,
target_size));
break;
case offsetof(struct __sk_buff, vlan_present):
case offsetof(struct __sk_buff, vlan_tci):
BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, vlan_tci, 2,
target_size));
if (si->off == offsetof(struct __sk_buff, vlan_tci)) {
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg,
~VLAN_TAG_PRESENT);
} else {
*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 12);
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1);
}
break;
case offsetof(struct __sk_buff, cb[0]) ...
offsetofend(struct __sk_buff, cb[4]) - 1:
BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, data) < 20);
BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
offsetof(struct qdisc_skb_cb, data)) %
sizeof(__u64));
prog->cb_access = 1;
off = si->off;
off -= offsetof(struct __sk_buff, cb[0]);
off += offsetof(struct sk_buff, cb);
off += offsetof(struct qdisc_skb_cb, data);
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg,
si->src_reg, off);
else
*insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
si->src_reg, off);
break;
case offsetof(struct __sk_buff, tc_classid):
BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, tc_classid) != 2);
off = si->off;
off -= offsetof(struct __sk_buff, tc_classid);
off += offsetof(struct sk_buff, cb);
off += offsetof(struct qdisc_skb_cb, tc_classid);
*target_size = 2;
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_H, si->dst_reg,
si->src_reg, off);
else
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg,
si->src_reg, off);
break;
case offsetof(struct __sk_buff, data):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
si->dst_reg, si->src_reg,
offsetof(struct sk_buff, data));
break;
case offsetof(struct __sk_buff, data_meta):
off = si->off;
off -= offsetof(struct __sk_buff, data_meta);
off += offsetof(struct sk_buff, cb);
off += offsetof(struct bpf_skb_data_end, data_meta);
*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
si->src_reg, off);
break;
case offsetof(struct __sk_buff, data_end):
off = si->off;
off -= offsetof(struct __sk_buff, data_end);
off += offsetof(struct sk_buff, cb);
off += offsetof(struct bpf_skb_data_end, data_end);
*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
si->src_reg, off);
break;
case offsetof(struct __sk_buff, tc_index):
#ifdef CONFIG_NET_SCHED
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, tc_index, 2,
target_size));
else
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, tc_index, 2,
target_size));
#else
*target_size = 2;
if (type == BPF_WRITE)
*insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg);
else
*insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
#endif
break;
case offsetof(struct __sk_buff, napi_id):
#if defined(CONFIG_NET_RX_BUSY_POLL)
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, napi_id, 4,
target_size));
*insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1);
*insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
#else
*target_size = 4;
*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;
}
static u32 sock_filter_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
switch (si->off) {
case offsetof(struct bpf_sock, bound_dev_if):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_bound_dev_if) != 4);
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
offsetof(struct sock, sk_bound_dev_if));
else
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
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);
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
offsetof(struct sock, sk_family));
break;
case offsetof(struct bpf_sock, type):
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
offsetof(struct sock, __sk_flags_offset));
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK);
*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT);
break;
case offsetof(struct bpf_sock, protocol):
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
offsetof(struct sock, __sk_flags_offset));
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK);
*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_PROTO_SHIFT);
break;
}
return insn - insn_buf;
}
static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
switch (si->off) {
case offsetof(struct __sk_buff, ifindex):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
si->dst_reg, si->src_reg,
offsetof(struct sk_buff, dev));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
bpf_target_off(struct net_device, ifindex, 4,
target_size));
break;
default:
return bpf_convert_ctx_access(type, si, insn_buf, prog,
target_size);
}
return insn - insn_buf;
}
static u32 xdp_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
switch (si->off) {
case offsetof(struct xdp_md, data):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data),
si->dst_reg, si->src_reg,
offsetof(struct xdp_buff, data));
break;
case offsetof(struct xdp_md, data_meta):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta),
si->dst_reg, si->src_reg,
offsetof(struct xdp_buff, data_meta));
break;
case offsetof(struct xdp_md, data_end):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end),
si->dst_reg, si->src_reg,
offsetof(struct xdp_buff, data_end));
break;
}
return insn - insn_buf;
}
static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
struct bpf_prog *prog,
u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
int off;
switch (si->off) {
case offsetof(struct bpf_sock_ops, op) ...
offsetof(struct bpf_sock_ops, replylong[3]):
BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, op) !=
FIELD_SIZEOF(struct bpf_sock_ops_kern, op));
BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, reply) !=
FIELD_SIZEOF(struct bpf_sock_ops_kern, reply));
BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, replylong) !=
FIELD_SIZEOF(struct bpf_sock_ops_kern, replylong));
off = si->off;
off -= offsetof(struct bpf_sock_ops, op);
off += offsetof(struct bpf_sock_ops_kern, op);
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
off);
else
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
off);
break;
case offsetof(struct bpf_sock_ops, family):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, sk));
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
offsetof(struct sock_common, skc_family));
break;
case offsetof(struct bpf_sock_ops, remote_ip4):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct sock_common, skc_daddr));
break;
case offsetof(struct bpf_sock_ops, local_ip4):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_rcv_saddr) != 4);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct sock_common,
skc_rcv_saddr));
break;
case offsetof(struct bpf_sock_ops, remote_ip6[0]) ...
offsetof(struct bpf_sock_ops, 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 bpf_sock_ops, remote_ip6[0]);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, 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 bpf_sock_ops, local_ip6[0]) ...
offsetof(struct bpf_sock_ops, 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 bpf_sock_ops, local_ip6[0]);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, 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 bpf_sock_ops, remote_port):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, sk));
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
offsetof(struct sock_common, skc_dport));
#ifndef __BIG_ENDIAN_BITFIELD
*insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
#endif
break;
case offsetof(struct bpf_sock_ops, local_port):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, sk));
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
offsetof(struct sock_common, skc_num));
break;
}
return insn - insn_buf;
}
static u32 sk_skb_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
int off;
switch (si->off) {
case offsetof(struct __sk_buff, data_end):
off = si->off;
off -= offsetof(struct __sk_buff, data_end);
off += offsetof(struct sk_buff, cb);
off += offsetof(struct tcp_skb_cb, bpf.data_end);
*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
si->src_reg, off);
break;
default:
return bpf_convert_ctx_access(type, si, insn_buf, prog,
target_size);
}
return insn - insn_buf;
}
const struct bpf_verifier_ops sk_filter_verifier_ops = {
.get_func_proto = sk_filter_func_proto,
.is_valid_access = sk_filter_is_valid_access,
.convert_ctx_access = bpf_convert_ctx_access,
};
const struct bpf_prog_ops sk_filter_prog_ops = {
};
const struct bpf_verifier_ops tc_cls_act_verifier_ops = {
.get_func_proto = tc_cls_act_func_proto,
.is_valid_access = tc_cls_act_is_valid_access,
.convert_ctx_access = tc_cls_act_convert_ctx_access,
.gen_prologue = tc_cls_act_prologue,
};
const struct bpf_prog_ops tc_cls_act_prog_ops = {
.test_run = bpf_prog_test_run_skb,
};
const struct bpf_verifier_ops xdp_verifier_ops = {
.get_func_proto = xdp_func_proto,
.is_valid_access = xdp_is_valid_access,
.convert_ctx_access = xdp_convert_ctx_access,
};
const struct bpf_prog_ops xdp_prog_ops = {
.test_run = bpf_prog_test_run_xdp,
};
const struct bpf_verifier_ops cg_skb_verifier_ops = {
.get_func_proto = sk_filter_func_proto,
.is_valid_access = sk_filter_is_valid_access,
.convert_ctx_access = bpf_convert_ctx_access,
};
const struct bpf_prog_ops cg_skb_prog_ops = {
.test_run = bpf_prog_test_run_skb,
};
const struct bpf_verifier_ops lwt_inout_verifier_ops = {
.get_func_proto = lwt_inout_func_proto,
.is_valid_access = lwt_is_valid_access,
.convert_ctx_access = bpf_convert_ctx_access,
};
const struct bpf_prog_ops lwt_inout_prog_ops = {
.test_run = bpf_prog_test_run_skb,
};
const struct bpf_verifier_ops lwt_xmit_verifier_ops = {
.get_func_proto = lwt_xmit_func_proto,
.is_valid_access = lwt_is_valid_access,
.convert_ctx_access = bpf_convert_ctx_access,
.gen_prologue = tc_cls_act_prologue,
};
const struct bpf_prog_ops lwt_xmit_prog_ops = {
.test_run = bpf_prog_test_run_skb,
};
const struct bpf_verifier_ops cg_sock_verifier_ops = {
.get_func_proto = sock_filter_func_proto,
.is_valid_access = sock_filter_is_valid_access,
.convert_ctx_access = sock_filter_convert_ctx_access,
};
const struct bpf_prog_ops cg_sock_prog_ops = {
};
const struct bpf_verifier_ops sock_ops_verifier_ops = {
.get_func_proto = sock_ops_func_proto,
.is_valid_access = sock_ops_is_valid_access,
.convert_ctx_access = sock_ops_convert_ctx_access,
};
const struct bpf_prog_ops sock_ops_prog_ops = {
};
const struct bpf_verifier_ops sk_skb_verifier_ops = {
.get_func_proto = sk_skb_func_proto,
.is_valid_access = sk_skb_is_valid_access,
.convert_ctx_access = sk_skb_convert_ctx_access,
.gen_prologue = sk_skb_prologue,
};
const struct bpf_prog_ops sk_skb_prog_ops = {
};
int sk_detach_filter(struct sock *sk)
{
int ret = -ENOENT;
struct sk_filter *filter;
if (sock_flag(sk, SOCK_FILTER_LOCKED))
return -EPERM;
filter = rcu_dereference_protected(sk->sk_filter,
lockdep_sock_is_held(sk));
if (filter) {
RCU_INIT_POINTER(sk->sk_filter, NULL);
sk_filter_uncharge(sk, filter);
ret = 0;
}
return ret;
}
EXPORT_SYMBOL_GPL(sk_detach_filter);
int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf,
unsigned int len)
{
struct sock_fprog_kern *fprog;
struct sk_filter *filter;
int ret = 0;
lock_sock(sk);
filter = rcu_dereference_protected(sk->sk_filter,
lockdep_sock_is_held(sk));
if (!filter)
goto out;
/* We're copying the filter that has been originally attached,
* so no conversion/decode needed anymore. eBPF programs that
* have no original program cannot be dumped through this.
*/
ret = -EACCES;
fprog = filter->prog->orig_prog;
if (!fprog)
goto out;
ret = fprog->len;
if (!len)
/* User space only enquires number of filter blocks. */
goto out;
ret = -EINVAL;
if (len < fprog->len)
goto out;
ret = -EFAULT;
if (copy_to_user(ubuf, fprog->filter, bpf_classic_proglen(fprog)))
goto out;
/* Instead of bytes, the API requests to return the number
* of filter blocks.
*/
ret = fprog->len;
out:
release_sock(sk);
return ret;
}
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