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ebpf_fuzzer.h
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ebpf_fuzzer.h
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#ifndef EBPF_FUZZER_H_LEVT96MB
#define EBPF_FUZZER_H_LEVT96MB
#include <clib.h>
#include "./common.h"
#define BODY_LEN 0x10000
struct ebpf_fuzz_target {
struct list_head sibling;
char *target_name;
char *sample_header;
char *sample_tail;
int (*init)(struct ebpf_fuzz_target *target);
int (*gen_sample_body)(char *b, size_t len,
u32 body1_max);
};
extern int insn_print_common(char *buf, size_t buflen, struct bpf_insn *insn,
size_t cnt);
extern int init(void);
extern struct ebpf_fuzz_target *find_target(char *version);
#ifndef BPF_JMP32
#define BPF_JMP32 0x06
#endif
/* 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_2 /* scratch reg */
#define BPF_REG_D BPF_REG_8 /* data, callee-saved */
#define BPF_REG_H BPF_REG_9 /* hlen, callee-saved */
/* Kernel hidden auxiliary/helper register. */
#define BPF_REG_AX MAX_BPF_REG
#define MAX_BPF_EXT_REG (MAX_BPF_REG + 1)
#define MAX_BPF_JIT_REG MAX_BPF_EXT_REG
/* unused opcode to mark special call to bpf_tail_call() helper */
#define BPF_TAIL_CALL 0xf0
/* unused opcode to mark call to interpreter with arguments */
#define BPF_CALL_ARGS 0xe0
/* 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 })
/* Special form of mov32, used for doing explicit zero extension on dst. */
#define BPF_ZEXT_REG(DST) \
((struct bpf_insn) { \
.code = BPF_ALU | BPF_MOV | BPF_X, \
.dst_reg = DST, \
.src_reg = DST, \
.off = 0, \
.imm = 1 })
/* 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 })
/* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */
#define BPF_JMP32_REG(OP, DST, SRC, OFF) \
((struct bpf_insn) { \
.code = BPF_JMP32 | BPF_OP(OP) | BPF_X, \
.dst_reg = DST, \
.src_reg = SRC, \
.off = OFF, \
.imm = 0 })
/* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */
#define BPF_JMP32_IMM(OP, DST, IMM, OFF) \
((struct bpf_insn) { \
.code = BPF_JMP32 | 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 })
/* Relative call */
#define BPF_CALL_REL(TGT) \
((struct bpf_insn) { \
.code = BPF_JMP | BPF_CALL, \
.dst_reg = 0, \
.src_reg = BPF_PSEUDO_CALL, \
.off = 0, \
.imm = TGT })
#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 })
#define LISTENER_PORT (1337)
#define LISTENER_BACKLOG (0x30)
#define STORAGE_MAP_SIZE (8192)
#define FUZZ_MAP_SIZE (8192)
#define ARRAY_CNT(arr) (sizeof(arr) / sizeof(arr[0]))
#define CORRUPT_FD_CONST 10
#define STORAGE_FD_CONST 11
#define CORRUPT_REG BPF_REG_9
#define STORAGE_REG BPF_REG_8
#define SPECIAL_REG BPF_REG_7
#define INVALID_P_REG BPF_REG_6
#define LEAKED_V_REG BPF_REG_5
#define UMAX_REG BPF_REG_4
#define EXTRA0_REG BPF_REG_3
#define EXTRA1_REG BPF_REG_2
#define EXTRA2_REG BPF_REG_1
#define MAGIC_VAL1 0x4142434445464748
#define MAGIC_VAL2 0x494a4b4c4d4e4f40
#define EBPF_INSN_GET_MAP_ADDR(fd, reg) \
BPF_MOV64_IMM(BPF_REG_0, 0), \
BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_0, -4), \
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), \
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4), \
BPF_LD_MAP_FD(BPF_REG_1, fd), \
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), \
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1), \
BPF_EXIT_INSN(), \
BPF_MOV64_REG((reg), BPF_REG_0), \
BPF_MOV64_IMM(BPF_REG_0, 0)
/* TODO */
struct reg_usage {
int id;
int in_use: 1;
int exclusive: 1;
};
static inline int insn_add_one(struct bpf_insn *insns, int *idx, int max,
struct bpf_insn insn)
{
int start = *idx;
int end = start + 1;
if (end > max) {
return -1;
}
insns[start] = insn;
*idx = end;
return 0;
}
static inline int insn_add(struct bpf_insn *insns, int *idx, int max,
struct bpf_insn *src_insn, int src_insn_count)
{
int err = 0;
for (int i = 0; i < src_insn_count; i++) {
err = insn_add_one(insns, idx, max, src_insn[i]);
if (err < 0)
return -1;
}
return 0;
}
static inline int insn_get_map_ptr(struct bpf_insn *insns, int *idx, int max,
int fd, int reg)
{
struct bpf_insn map_p[] = {
EBPF_INSN_GET_MAP_ADDR(fd, reg),
};
return insn_add(insns, idx, max, map_p, ARRAY_CNT(map_p));
}
#define COPY_INSNS(dst, IDX, src) \
({\
int err = 0;\
struct bpf_insn ____insns[] = {src};\
err = insn_add(dst, (int *)&IDX, BPF_MAXINSNS, ____insns, ARRAY_CNT(____insns));\
if (err < 0) \
return -1;\
})
extern int gen_non_insn(struct bpf_insn *insns, int *idx);
extern int gen_jmp_insn_common(struct bpf_insn *insns, int *idx, int is_imm,
int is_64, int reg0, int reg1, long imm_v, int op);
extern int gen_alu_insn_common(struct bpf_insn *insns, int *idx, int is_imm,
int is_64, int reg0, int reg1, long imm_v, int op);
extern int gen_mov_insn_common(struct bpf_insn *insns, int *idx, int is_imm,
int is_64, int reg0, int reg1, long imm_v);
extern int gen_ld_insn_common(struct bpf_insn *insn, int *idx, int reg0, long imm_v);
#endif /* end of include guard: EBPF_FUZZER_H_LEVT96MB */