/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Linux Socket Filter Data Structures
 */
#ifndef __LINUX_FILTER_H__
#define __LINUX_FILTER_H__

#include <stdarg.h>

#include <linux/atomic.h>
#include <linux/refcount.h>
#include <linux/compat.h>
#include <linux/skbuff.h>
#include <linux/linkage.h>
#include <linux/printk.h>
#include <linux/workqueue.h>
#include <linux/sched.h>
#include <linux/capability.h>
#include <linux/cryptohash.h>
#include <linux/set_memory.h>

#include <net/sch_generic.h>

#include <uapi/linux/filter.h>
#include <uapi/linux/bpf.h>

struct sk_buff;
struct sock;
struct seccomp_data;
struct bpf_prog_aux;

/* ArgX, context and stack frame pointer register positions. Note,
 * Arg1, Arg2, Arg3, etc are used as argument mappings of function
 * calls in BPF_CALL instruction.
 */
#define BPF_REG_ARG1    BPF_REG_1
#define BPF_REG_ARG2    BPF_REG_2
#define BPF_REG_ARG3    BPF_REG_3
#define BPF_REG_ARG4    BPF_REG_4
#define BPF_REG_ARG5    BPF_REG_5
#define BPF_REG_CTX     BPF_REG_6
#define BPF_REG_FP      BPF_REG_10

/* Additional register mappings for converted user programs. */
#define BPF_REG_A       BPF_REG_0
#define BPF_REG_X       BPF_REG_7
#define BPF_REG_TMP     BPF_REG_8

/* Kernel hidden auxiliary/helper register for hardening step.
 * Only used by eBPF JITs. It's nothing more than a temporary
 * register that JITs use internally, only that here it's part
 * of eBPF instructions that have been rewritten for blinding
 * constants. See JIT pre-step in bpf_jit_blind_constants().
 */
#define BPF_REG_AX              MAX_BPF_REG
#define MAX_BPF_JIT_REG         (MAX_BPF_REG + 1)

/* unused opcode to mark special call to bpf_tail_call() helper */
#define BPF_TAIL_CALL   0xf0

/* As per nm, we expose JITed images as text (code) section for
 * kallsyms. That way, tools like perf can find it to match
 * addresses.
 */
#define BPF_SYM_ELF_TYPE        't'

/* BPF program can access up to 512 bytes of stack space. */
#define MAX_BPF_STACK   512

/* Helper macros for filter block array initializers. */

/* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */

#define BPF_ALU64_REG(OP, DST, SRC)                             \
        ((struct bpf_insn) {                                    \
                .code  = BPF_ALU64 | BPF_OP(OP) | BPF_X,        \
                .dst_reg = DST,                                 \
                .src_reg = SRC,                                 \
                .off   = 0,                                     \
                .imm   = 0 })

#define BPF_ALU32_REG(OP, DST, SRC)                             \
        ((struct bpf_insn) {                                    \
                .code  = BPF_ALU | BPF_OP(OP) | BPF_X,          \
                .dst_reg = DST,                                 \
                .src_reg = SRC,                                 \
                .off   = 0,                                     \
                .imm   = 0 })

/* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */

#define BPF_ALU64_IMM(OP, DST, IMM)                             \
        ((struct bpf_insn) {                                    \
                .code  = BPF_ALU64 | BPF_OP(OP) | BPF_K,        \
                .dst_reg = DST,                                 \
                .src_reg = 0,                                   \
                .off   = 0,                                     \
                .imm   = IMM })

#define BPF_ALU32_IMM(OP, DST, IMM)                             \
        ((struct bpf_insn) {                                    \
                .code  = BPF_ALU | BPF_OP(OP) | BPF_K,          \
                .dst_reg = DST,                                 \
                .src_reg = 0,                                   \
                .off   = 0,                                     \
                .imm   = IMM })

/* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */

#define BPF_ENDIAN(TYPE, DST, LEN)                              \
        ((struct bpf_insn) {                                    \
                .code  = BPF_ALU | BPF_END | BPF_SRC(TYPE),     \
                .dst_reg = DST,                                 \
                .src_reg = 0,                                   \
                .off   = 0,                                     \
                .imm   = LEN })

/* Short form of mov, dst_reg = src_reg */

#define BPF_MOV64_REG(DST, SRC)                                 \
        ((struct bpf_insn) {                                    \
                .code  = BPF_ALU64 | BPF_MOV | BPF_X,           \
                .dst_reg = DST,                                 \
                .src_reg = SRC,                                 \
                .off   = 0,                                     \
                .imm   = 0 })

#define BPF_MOV32_REG(DST, SRC)                                 \
        ((struct bpf_insn) {                                    \
                .code  = BPF_ALU | BPF_MOV | BPF_X,             \
                .dst_reg = DST,                                 \
                .src_reg = SRC,                                 \
                .off   = 0,                                     \
                .imm   = 0 })

/* Short form of mov, dst_reg = imm32 */

#define BPF_MOV64_IMM(DST, IMM)                                 \
        ((struct bpf_insn) {                                    \
                .code  = BPF_ALU64 | BPF_MOV | BPF_K,           \
                .dst_reg = DST,                                 \
                .src_reg = 0,                                   \
                .off   = 0,                                     \
                .imm   = IMM })

#define BPF_MOV32_IMM(DST, IMM)                                 \
        ((struct bpf_insn) {                                    \
                .code  = BPF_ALU | BPF_MOV | BPF_K,             \
                .dst_reg = DST,                                 \
                .src_reg = 0,                                   \
                .off   = 0,                                     \
                .imm   = IMM })

/* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */
#define BPF_LD_IMM64(DST, IMM)                                  \
        BPF_LD_IMM64_RAW(DST, 0, IMM)

#define BPF_LD_IMM64_RAW(DST, SRC, IMM)                         \
        ((struct bpf_insn) {                                    \
                .code  = BPF_LD | BPF_DW | BPF_IMM,             \
                .dst_reg = DST,                                 \
                .src_reg = SRC,                                 \
                .off   = 0,                                     \
                .imm   = (__u32) (IMM) }),                      \
        ((struct bpf_insn) {                                    \
                .code  = 0, /* zero is reserved opcode */       \
                .dst_reg = 0,                                   \
                .src_reg = 0,                                   \
                .off   = 0,                                     \
                .imm   = ((__u64) (IMM)) >> 32 })

/* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */
#define BPF_LD_MAP_FD(DST, MAP_FD)                              \
        BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD)

/* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */

#define BPF_MOV64_RAW(TYPE, DST, SRC, IMM)                      \
        ((struct bpf_insn) {                                    \
                .code  = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE),   \
                .dst_reg = DST,                                 \
                .src_reg = SRC,                                 \
                .off   = 0,                                     \
                .imm   = IMM })

#define BPF_MOV32_RAW(TYPE, DST, SRC, IMM)                      \
        ((struct bpf_insn) {                                    \
                .code  = BPF_ALU | BPF_MOV | BPF_SRC(TYPE),     \
                .dst_reg = DST,                                 \
                .src_reg = SRC,                                 \
                .off   = 0,                                     \
                .imm   = IMM })

/* Direct packet access, R0 = *(uint *) (skb->data + imm32) */

#define BPF_LD_ABS(SIZE, IMM)                                   \
        ((struct bpf_insn) {                                    \
                .code  = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS,     \
                .dst_reg = 0,                                   \
                .src_reg = 0,                                   \
                .off   = 0,                                     \
                .imm   = IMM })

/* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */

#define BPF_LD_IND(SIZE, SRC, IMM)                              \
        ((struct bpf_insn) {                                    \
                .code  = BPF_LD | BPF_SIZE(SIZE) | BPF_IND,     \
                .dst_reg = 0,                                   \
                .src_reg = SRC,                                 \
                .off   = 0,                                     \
                .imm   = IMM })

/* Memory load, dst_reg = *(uint *) (src_reg + off16) */

#define BPF_LDX_MEM(SIZE, DST, SRC, OFF)                        \
        ((struct bpf_insn) {                                    \
                .code  = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM,    \
                .dst_reg = DST,                                 \
                .src_reg = SRC,                                 \
                .off   = OFF,                                   \
                .imm   = 0 })

/* Memory store, *(uint *) (dst_reg + off16) = src_reg */

#define BPF_STX_MEM(SIZE, DST, SRC, OFF)                        \
        ((struct bpf_insn) {                                    \
                .code  = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM,    \
                .dst_reg = DST,                                 \
                .src_reg = SRC,                                 \
                .off   = OFF,                                   \
                .imm   = 0 })

/* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */

#define BPF_STX_XADD(SIZE, DST, SRC, OFF)                       \
        ((struct bpf_insn) {                                    \
                .code  = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD,   \
                .dst_reg = DST,                                 \
                .src_reg = SRC,                                 \
                .off   = OFF,                                   \
                .imm   = 0 })

/* Memory store, *(uint *) (dst_reg + off16) = imm32 */

#define BPF_ST_MEM(SIZE, DST, OFF, IMM)                         \
        ((struct bpf_insn) {                                    \
                .code  = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM,     \
                .dst_reg = DST,                                 \
                .src_reg = 0,                                   \
                .off   = OFF,                                   \
                .imm   = IMM })

/* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */

#define BPF_JMP_REG(OP, DST, SRC, OFF)                          \
        ((struct bpf_insn) {                                    \
                .code  = BPF_JMP | BPF_OP(OP) | BPF_X,          \
                .dst_reg = DST,                                 \
                .src_reg = SRC,                                 \
                .off   = OFF,                                   \
                .imm   = 0 })

/* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */

#define BPF_JMP_IMM(OP, DST, IMM, OFF)                          \
        ((struct bpf_insn) {                                    \
                .code  = BPF_JMP | BPF_OP(OP) | BPF_K,          \
                .dst_reg = DST,                                 \
                .src_reg = 0,                                   \
                .off   = OFF,                                   \
                .imm   = IMM })

/* Unconditional jumps, goto pc + off16 */

#define BPF_JMP_A(OFF)                                          \
        ((struct bpf_insn) {                                    \
                .code  = BPF_JMP | BPF_JA,                      \
                .dst_reg = 0,                                   \
                .src_reg = 0,                                   \
                .off   = OFF,                                   \
                .imm   = 0 })

/* Function call */

#define BPF_EMIT_CALL(FUNC)                                     \
        ((struct bpf_insn) {                                    \
                .code  = BPF_JMP | BPF_CALL,                    \
                .dst_reg = 0,                                   \
                .src_reg = 0,                                   \
                .off   = 0,                                     \
                .imm   = ((FUNC) - __bpf_call_base) })

/* Raw code statement block */

#define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM)                  \
        ((struct bpf_insn) {                                    \
                .code  = CODE,                                  \
                .dst_reg = DST,                                 \
                .src_reg = SRC,                                 \
                .off   = OFF,                                   \
                .imm   = IMM })

/* Program exit */

#define BPF_EXIT_INSN()                                         \
        ((struct bpf_insn) {                                    \
                .code  = BPF_JMP | BPF_EXIT,                    \
                .dst_reg = 0,                                   \
                .src_reg = 0,                                   \
                .off   = 0,                                     \
                .imm   = 0 })

/* Internal classic blocks for direct assignment */

#define __BPF_STMT(CODE, K)                                     \
        ((struct sock_filter) BPF_STMT(CODE, K))

#define __BPF_JUMP(CODE, K, JT, JF)                             \
        ((struct sock_filter) BPF_JUMP(CODE, K, JT, JF))

#define bytes_to_bpf_size(bytes)                                \
({                                                              \
        int bpf_size = -EINVAL;                                 \
                                                                \
        if (bytes == sizeof(u8))                                \
                bpf_size = BPF_B;                               \
        else if (bytes == sizeof(u16))                          \
                bpf_size = BPF_H;                               \
        else if (bytes == sizeof(u32))                          \
                bpf_size = BPF_W;                               \
        else if (bytes == sizeof(u64))                          \
                bpf_size = BPF_DW;                              \
                                                                \
        bpf_size;                                               \
})

#define bpf_size_to_bytes(bpf_size)                             \
({                                                              \
        int bytes = -EINVAL;                                    \
                                                                \
        if (bpf_size == BPF_B)                                  \
                bytes = sizeof(u8);                             \
        else if (bpf_size == BPF_H)                             \
                bytes = sizeof(u16);                            \
        else if (bpf_size == BPF_W)                             \
                bytes = sizeof(u32);                            \
        else if (bpf_size == BPF_DW)                            \
                bytes = sizeof(u64);                            \
                                                                \
        bytes;                                                  \
})

#define BPF_SIZEOF(type)                                        \
        ({                                                      \
                const int __size = bytes_to_bpf_size(sizeof(type)); \
                BUILD_BUG_ON(__size < 0);                       \
                __size;                                         \
        })

#define BPF_FIELD_SIZEOF(type, field)                           \
        ({                                                      \
                const int __size = bytes_to_bpf_size(FIELD_SIZEOF(type, field)); \
                BUILD_BUG_ON(__size < 0);                       \
                __size;                                         \
        })

#define BPF_LDST_BYTES(insn)                                    \
        ({                                                      \
                const int __size = bpf_size_to_bytes(BPF_SIZE(insn->code)); \
                WARN_ON(__size < 0);                            \
                __size;                                         \
        })

#define __BPF_MAP_0(m, v, ...) v
#define __BPF_MAP_1(m, v, t, a, ...) m(t, a)
#define __BPF_MAP_2(m, v, t, a, ...) m(t, a), __BPF_MAP_1(m, v, __VA_ARGS__)
#define __BPF_MAP_3(m, v, t, a, ...) m(t, a), __BPF_MAP_2(m, v, __VA_ARGS__)
#define __BPF_MAP_4(m, v, t, a, ...) m(t, a), __BPF_MAP_3(m, v, __VA_ARGS__)
#define __BPF_MAP_5(m, v, t, a, ...) m(t, a), __BPF_MAP_4(m, v, __VA_ARGS__)

#define __BPF_REG_0(...) __BPF_PAD(5)
#define __BPF_REG_1(...) __BPF_MAP(1, __VA_ARGS__), __BPF_PAD(4)
#define __BPF_REG_2(...) __BPF_MAP(2, __VA_ARGS__), __BPF_PAD(3)
#define __BPF_REG_3(...) __BPF_MAP(3, __VA_ARGS__), __BPF_PAD(2)
#define __BPF_REG_4(...) __BPF_MAP(4, __VA_ARGS__), __BPF_PAD(1)
#define __BPF_REG_5(...) __BPF_MAP(5, __VA_ARGS__)

#define __BPF_MAP(n, ...) __BPF_MAP_##n(__VA_ARGS__)
#define __BPF_REG(n, ...) __BPF_REG_##n(__VA_ARGS__)

#define __BPF_CAST(t, a)                                                       \
        (__force t)                                                            \
        (__force                                                               \
         typeof(__builtin_choose_expr(sizeof(t) == sizeof(unsigned long),      \
                                      (unsigned long)0, (t)0))) a
#define __BPF_V void
#define __BPF_N

#define __BPF_DECL_ARGS(t, a) t   a
#define __BPF_DECL_REGS(t, a) u64 a

#define __BPF_PAD(n)                                                           \
        __BPF_MAP(n, __BPF_DECL_ARGS, __BPF_N, u64, __ur_1, u64, __ur_2,       \
                  u64, __ur_3, u64, __ur_4, u64, __ur_5)

#define BPF_CALL_x(x, name, ...)                                               \
        static __always_inline                                                 \
        u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__));   \
        u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__));         \
        u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__))          \
        {                                                                      \
                return ____##name(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\
        }                                                                      \
        static __always_inline                                                 \
        u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__))

#define BPF_CALL_0(name, ...)   BPF_CALL_x(0, name, __VA_ARGS__)
#define BPF_CALL_1(name, ...)   BPF_CALL_x(1, name, __VA_ARGS__)
#define BPF_CALL_2(name, ...)   BPF_CALL_x(2, name, __VA_ARGS__)
#define BPF_CALL_3(name, ...)   BPF_CALL_x(3, name, __VA_ARGS__)
#define BPF_CALL_4(name, ...)   BPF_CALL_x(4, name, __VA_ARGS__)
#define BPF_CALL_5(name, ...)   BPF_CALL_x(5, name, __VA_ARGS__)

#define bpf_ctx_range(TYPE, MEMBER)                                             \
        offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
#define bpf_ctx_range_till(TYPE, MEMBER1, MEMBER2)                              \
        offsetof(TYPE, MEMBER1) ... offsetofend(TYPE, MEMBER2) - 1

#define bpf_target_off(TYPE, MEMBER, SIZE, PTR_SIZE)                            \
        ({                                                                      \
                BUILD_BUG_ON(FIELD_SIZEOF(TYPE, MEMBER) != (SIZE));             \
                *(PTR_SIZE) = (SIZE);                                           \
                offsetof(TYPE, MEMBER);                                         \
        })

#ifdef CONFIG_COMPAT
/* A struct sock_filter is architecture independent. */
struct compat_sock_fprog {
        u16             len;
        compat_uptr_t   filter; /* struct sock_filter * */
};
#endif

struct sock_fprog_kern {
        u16                     len;
        struct sock_filter      *filter;
};

struct bpf_binary_header {
        unsigned int pages;
        u8 image[];
};

struct bpf_prog {
        u16                     pages;          /* Number of allocated pages */
        kmemcheck_bitfield_begin(meta);
        u16                     jited:1,        /* Is our filter JIT'ed? */
                                locked:1,       /* Program image locked? */
                                gpl_compatible:1, /* Is filter GPL compatible? */
                                cb_access:1,    /* Is control block accessed? */
                                dst_needed:1;   /* Do we need dst entry? */
        kmemcheck_bitfield_end(meta);
        enum bpf_prog_type      type;           /* Type of BPF program */
        u32                     len;            /* Number of filter blocks */
        u32                     jited_len;      /* Size of jited insns in bytes */
        u8                      tag[BPF_TAG_SIZE];
        struct bpf_prog_aux     *aux;           /* Auxiliary fields */
        struct sock_fprog_kern  *orig_prog;     /* Original BPF program */
        unsigned int            (*bpf_func)(const void *ctx,
                                            const struct bpf_insn *insn);
        /* Instructions for interpreter */
        union {
                struct sock_filter      insns[0];
                struct bpf_insn         insnsi[0];
        };
};

struct sk_filter {
        refcount_t      refcnt;
        struct rcu_head rcu;
        struct bpf_prog *prog;
};

#define BPF_PROG_RUN(filter, ctx)  (*filter->bpf_func)(ctx, filter->insnsi)

#define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN

struct bpf_skb_data_end {
        struct qdisc_skb_cb qdisc_cb;
        void *data_end;
};

struct xdp_buff {
        void *data;
        void *data_end;
        void *data_hard_start;
};

/* compute the linear packet data range [data, data_end) which
 * will be accessed by cls_bpf, act_bpf and lwt programs
 */
static inline void bpf_compute_data_end(struct sk_buff *skb)
{
        struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;

        BUILD_BUG_ON(sizeof(*cb) > FIELD_SIZEOF(struct sk_buff, cb));
        cb->data_end = skb->data + skb_headlen(skb);
}

static inline u8 *bpf_skb_cb(struct sk_buff *skb)
{
        /* eBPF programs may read/write skb->cb[] area to transfer meta
         * data between tail calls. Since this also needs to work with
         * tc, that scratch memory is mapped to qdisc_skb_cb's data area.
         *
         * In some socket filter cases, the cb unfortunately needs to be
         * saved/restored so that protocol specific skb->cb[] data won't
         * be lost. In any case, due to unpriviledged eBPF programs
         * attached to sockets, we need to clear the bpf_skb_cb() area
         * to not leak previous contents to user space.
         */
        BUILD_BUG_ON(FIELD_SIZEOF(struct __sk_buff, cb) != BPF_SKB_CB_LEN);
        BUILD_BUG_ON(FIELD_SIZEOF(struct __sk_buff, cb) !=
                     FIELD_SIZEOF(struct qdisc_skb_cb, data));

        return qdisc_skb_cb(skb)->data;
}

static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog,
                                       struct sk_buff *skb)
{
        u8 *cb_data = bpf_skb_cb(skb);
        u8 cb_saved[BPF_SKB_CB_LEN];
        u32 res;

        if (unlikely(prog->cb_access)) {
                memcpy(cb_saved, cb_data, sizeof(cb_saved));
                memset(cb_data, 0, sizeof(cb_saved));
        }

        res = BPF_PROG_RUN(prog, skb);

        if (unlikely(prog->cb_access))
                memcpy(cb_data, cb_saved, sizeof(cb_saved));

        return res;
}

static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog,
                                        struct sk_buff *skb)
{
        u8 *cb_data = bpf_skb_cb(skb);

        if (unlikely(prog->cb_access))
                memset(cb_data, 0, BPF_SKB_CB_LEN);

        return BPF_PROG_RUN(prog, skb);
}

static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog,
                                            struct xdp_buff *xdp)
{
        /* Caller needs to hold rcu_read_lock() (!), otherwise program
         * can be released while still running, or map elements could be
         * freed early while still having concurrent users. XDP fastpath
         * already takes rcu_read_lock() when fetching the program, so
         * it's not necessary here anymore.
         */
        return BPF_PROG_RUN(prog, xdp);
}

static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog)
{
        return prog->len * sizeof(struct bpf_insn);
}

static inline u32 bpf_prog_tag_scratch_size(const struct bpf_prog *prog)
{
        return round_up(bpf_prog_insn_size(prog) +
                        sizeof(__be64) + 1, SHA_MESSAGE_BYTES);
}

static inline unsigned int bpf_prog_size(unsigned int proglen)
{
        return max(sizeof(struct bpf_prog),
                   offsetof(struct bpf_prog, insns[proglen]));
}

static inline bool bpf_prog_was_classic(const struct bpf_prog *prog)
{
        /* When classic BPF programs have been loaded and the arch
         * does not have a classic BPF JIT (anymore), they have been
         * converted via bpf_migrate_filter() to eBPF and thus always
         * have an unspec program type.
         */
        return prog->type == BPF_PROG_TYPE_UNSPEC;
}

static inline bool
bpf_ctx_narrow_access_ok(u32 off, u32 size, const u32 size_default)
{
        bool off_ok;
#ifdef __LITTLE_ENDIAN
        off_ok = (off & (size_default - 1)) == 0;
#else
        off_ok = (off & (size_default - 1)) + size == size_default;
#endif
        return off_ok && size <= size_default && (size & (size - 1)) == 0;
}

#define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0]))

#ifdef CONFIG_ARCH_HAS_SET_MEMORY
static inline void bpf_prog_lock_ro(struct bpf_prog *fp)
{
        fp->locked = 1;
        WARN_ON_ONCE(set_memory_ro((unsigned long)fp, fp->pages));
}

static inline void bpf_prog_unlock_ro(struct bpf_prog *fp)
{
        if (fp->locked) {
                WARN_ON_ONCE(set_memory_rw((unsigned long)fp, fp->pages));
                /* In case set_memory_rw() fails, we want to be the first
                 * to crash here instead of some random place later on.
                 */
                fp->locked = 0;
        }
}

static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr)
{
        WARN_ON_ONCE(set_memory_ro((unsigned long)hdr, hdr->pages));
}

static inline void bpf_jit_binary_unlock_ro(struct bpf_binary_header *hdr)
{
        WARN_ON_ONCE(set_memory_rw((unsigned long)hdr, hdr->pages));
}
#else
static inline void bpf_prog_lock_ro(struct bpf_prog *fp)
{
}

static inline void bpf_prog_unlock_ro(struct bpf_prog *fp)
{
}

static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr)
{
}

static inline void bpf_jit_binary_unlock_ro(struct bpf_binary_header *hdr)
{
}
#endif /* CONFIG_ARCH_HAS_SET_MEMORY */

static inline struct bpf_binary_header *
bpf_jit_binary_hdr(const struct bpf_prog *fp)
{
        unsigned long real_start = (unsigned long)fp->bpf_func;
        unsigned long addr = real_start & PAGE_MASK;

        return (void *)addr;
}

int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap);
static inline int sk_filter(struct sock *sk, struct sk_buff *skb)
{
        return sk_filter_trim_cap(sk, skb, 1);
}

struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err);
void bpf_prog_free(struct bpf_prog *fp);

struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags);
struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
                                  gfp_t gfp_extra_flags);
void __bpf_prog_free(struct bpf_prog *fp);

static inline void bpf_prog_unlock_free(struct bpf_prog *fp)
{
        bpf_prog_unlock_ro(fp);
        __bpf_prog_free(fp);
}

typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter,
                                       unsigned int flen);

int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog);
int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
                              bpf_aux_classic_check_t trans, bool save_orig);
void bpf_prog_destroy(struct bpf_prog *fp);

int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
int sk_attach_bpf(u32 ufd, struct sock *sk);
int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk);
int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk);
int sk_detach_filter(struct sock *sk);
int sk_get_filter(struct sock *sk, struct sock_filter __user *filter,
                  unsigned int len);

bool sk_filter_charge(struct sock *sk, struct sk_filter *fp);
void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp);

u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);

struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog);
void bpf_jit_compile(struct bpf_prog *prog);
bool bpf_helper_changes_pkt_data(void *func);

struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
                                       const struct bpf_insn *patch, u32 len);

/* The pair of xdp_do_redirect and xdp_do_flush_map MUST be called in the
 * same cpu context. Further for best results no more than a single map
 * for the do_redirect/do_flush pair should be used. This limitation is
 * because we only track one map and force a flush when the map changes.
 * This does not appear to be a real limitation for existing software.
 */
int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
                            struct bpf_prog *prog);
int xdp_do_redirect(struct net_device *dev,
                    struct xdp_buff *xdp,
                    struct bpf_prog *prog);
void xdp_do_flush_map(void);

void bpf_warn_invalid_xdp_action(u32 act);
void bpf_warn_invalid_xdp_redirect(u32 ifindex);

struct sock *do_sk_redirect_map(struct sk_buff *skb);

#ifdef CONFIG_BPF_JIT
extern int bpf_jit_enable;
extern int bpf_jit_harden;
extern int bpf_jit_kallsyms;

typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size);

struct bpf_binary_header *
bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
                     unsigned int alignment,
                     bpf_jit_fill_hole_t bpf_fill_ill_insns);
void bpf_jit_binary_free(struct bpf_binary_header *hdr);

void bpf_jit_free(struct bpf_prog *fp);

struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp);
void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other);

static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
                                u32 pass, void *image)
{
        pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen,
               proglen, pass, image, current->comm, task_pid_nr(current));

        if (image)
                print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
                               16, 1, image, proglen, false);
}

static inline bool bpf_jit_is_ebpf(void)
{
# ifdef CONFIG_HAVE_EBPF_JIT
        return true;
# else
        return false;
# endif
}

static inline bool ebpf_jit_enabled(void)
{
        return bpf_jit_enable && bpf_jit_is_ebpf();
}

static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
{
        return fp->jited && bpf_jit_is_ebpf();
}

static inline bool bpf_jit_blinding_enabled(void)
{
        /* These are the prerequisites, should someone ever have the
         * idea to call blinding outside of them, we make sure to
         * bail out.
         */
        if (!bpf_jit_is_ebpf())
                return false;
        if (!bpf_jit_enable)
                return false;
        if (!bpf_jit_harden)
                return false;
        if (bpf_jit_harden == 1 && capable(CAP_SYS_ADMIN))
                return false;

        return true;
}

static inline bool bpf_jit_kallsyms_enabled(void)
{
        /* There are a couple of corner cases where kallsyms should
         * not be enabled f.e. on hardening.
         */
        if (bpf_jit_harden)
                return false;
        if (!bpf_jit_kallsyms)
                return false;
        if (bpf_jit_kallsyms == 1)
                return true;

        return false;
}

const char *__bpf_address_lookup(unsigned long addr, unsigned long *size,
                                 unsigned long *off, char *sym);
bool is_bpf_text_address(unsigned long addr);
int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
                    char *sym);

static inline const char *
bpf_address_lookup(unsigned long addr, unsigned long *size,
                   unsigned long *off, char **modname, char *sym)
{
        const char *ret = __bpf_address_lookup(addr, size, off, sym);

        if (ret && modname)
                *modname = NULL;
        return ret;
}

void bpf_prog_kallsyms_add(struct bpf_prog *fp);
void bpf_prog_kallsyms_del(struct bpf_prog *fp);

#else /* CONFIG_BPF_JIT */

static inline bool ebpf_jit_enabled(void)
{
        return false;
}

static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
{
        return false;
}

static inline void bpf_jit_free(struct bpf_prog *fp)
{
        bpf_prog_unlock_free(fp);
}

static inline bool bpf_jit_kallsyms_enabled(void)
{
        return false;
}

static inline const char *
__bpf_address_lookup(unsigned long addr, unsigned long *size,
                     unsigned long *off, char *sym)
{
        return NULL;
}

static inline bool is_bpf_text_address(unsigned long addr)
{
        return false;
}

static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value,
                                  char *type, char *sym)
{
        return -ERANGE;
}

static inline const char *
bpf_address_lookup(unsigned long addr, unsigned long *size,
                   unsigned long *off, char **modname, char *sym)
{
        return NULL;
}

static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp)
{
}

static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp)
{
}
#endif /* CONFIG_BPF_JIT */

#define BPF_ANC         BIT(15)

static inline bool bpf_needs_clear_a(const struct sock_filter *first)
{
        switch (first->code) {
        case BPF_RET | BPF_K:
        case BPF_LD | BPF_W | BPF_LEN:
                return false;

        case BPF_LD | BPF_W | BPF_ABS:
        case BPF_LD | BPF_H | BPF_ABS:
        case BPF_LD | BPF_B | BPF_ABS:
                if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X)
                        return true;
                return false;

        default:
                return true;
        }
}

static inline u16 bpf_anc_helper(const struct sock_filter *ftest)
{
        BUG_ON(ftest->code & BPF_ANC);

        switch (ftest->code) {
        case BPF_LD | BPF_W | BPF_ABS:
        case BPF_LD | BPF_H | BPF_ABS:
        case BPF_LD | BPF_B | BPF_ABS:
#define BPF_ANCILLARY(CODE)     case SKF_AD_OFF + SKF_AD_##CODE:        \
                                return BPF_ANC | SKF_AD_##CODE
                switch (ftest->k) {
                BPF_ANCILLARY(PROTOCOL);
                BPF_ANCILLARY(PKTTYPE);
                BPF_ANCILLARY(IFINDEX);
                BPF_ANCILLARY(NLATTR);
                BPF_ANCILLARY(NLATTR_NEST);
                BPF_ANCILLARY(MARK);
                BPF_ANCILLARY(QUEUE);
                BPF_ANCILLARY(HATYPE);
                BPF_ANCILLARY(RXHASH);
                BPF_ANCILLARY(CPU);
                BPF_ANCILLARY(ALU_XOR_X);
                BPF_ANCILLARY(VLAN_TAG);
                BPF_ANCILLARY(VLAN_TAG_PRESENT);
                BPF_ANCILLARY(PAY_OFFSET);
                BPF_ANCILLARY(RANDOM);
                BPF_ANCILLARY(VLAN_TPID);
                }
                /* Fallthrough. */
        default:
                return ftest->code;
        }
}

void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb,
                                           int k, unsigned int size);

static inline void *bpf_load_pointer(const struct sk_buff *skb, int k,
                                     unsigned int size, void *buffer)
{
        if (k >= 0)
                return skb_header_pointer(skb, k, size, buffer);

        return bpf_internal_load_pointer_neg_helper(skb, k, size);
}

static inline int bpf_tell_extensions(void)
{
        return SKF_AD_MAX;
}

struct bpf_sock_ops_kern {
        struct  sock *sk;
        u32     op;
        union {
                u32 reply;
                u32 replylong[4];
        };
};

#endif /* __LINUX_FILTER_H__ */