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#include <asm/types.h>
#include <linux/types.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stddef.h>
#include <stdbool.h>
#include <linux/unistd.h>
#include <linux/filter.h>
#include <linux/bpf_perf_event.h>
#include <linux/bpf.h>
#include <bpf/bpf.h>
#include "../../../include/linux/filter.h"
#ifndef ARRAY_SIZE
# define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
#endif
#define MAX_INSNS 512
#define MAX_MATCHES 16
struct bpf_align_test {
const char *descr;
struct bpf_insn insns[MAX_INSNS];
enum {
UNDEF,
ACCEPT,
REJECT
} result;
enum bpf_prog_type prog_type;
const char *matches[MAX_MATCHES];
};
static struct bpf_align_test tests[] = {
{
.descr = "mov",
.insns = {
BPF_MOV64_IMM(BPF_REG_3, 2),
BPF_MOV64_IMM(BPF_REG_3, 4),
BPF_MOV64_IMM(BPF_REG_3, 8),
BPF_MOV64_IMM(BPF_REG_3, 16),
BPF_MOV64_IMM(BPF_REG_3, 32),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
"1: R1=ctx R3=imm2,min_value=2,max_value=2,min_align=2 R10=fp",
"2: R1=ctx R3=imm4,min_value=4,max_value=4,min_align=4 R10=fp",
"3: R1=ctx R3=imm8,min_value=8,max_value=8,min_align=8 R10=fp",
"4: R1=ctx R3=imm16,min_value=16,max_value=16,min_align=16 R10=fp",
"5: R1=ctx R3=imm32,min_value=32,max_value=32,min_align=32 R10=fp",
},
},
{
.descr = "shift",
.insns = {
BPF_MOV64_IMM(BPF_REG_3, 1),
BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1),
BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1),
BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1),
BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1),
BPF_ALU64_IMM(BPF_RSH, BPF_REG_3, 4),
BPF_MOV64_IMM(BPF_REG_4, 32),
BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1),
BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1),
BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1),
BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
"1: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R10=fp",
"2: R1=ctx R3=imm2,min_value=2,max_value=2,min_align=2 R10=fp",
"3: R1=ctx R3=imm4,min_value=4,max_value=4,min_align=4 R10=fp",
"4: R1=ctx R3=imm8,min_value=8,max_value=8,min_align=8 R10=fp",
"5: R1=ctx R3=imm16,min_value=16,max_value=16,min_align=16 R10=fp",
"6: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R10=fp",
"7: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm32,min_value=32,max_value=32,min_align=32 R10=fp",
"8: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm16,min_value=16,max_value=16,min_align=16 R10=fp",
"9: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm8,min_value=8,max_value=8,min_align=8 R10=fp",
"10: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm4,min_value=4,max_value=4,min_align=4 R10=fp",
"11: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm2,min_value=2,max_value=2,min_align=2 R10=fp",
},
},
{
.descr = "addsub",
.insns = {
BPF_MOV64_IMM(BPF_REG_3, 4),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, 4),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, 2),
BPF_MOV64_IMM(BPF_REG_4, 8),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 2),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
"1: R1=ctx R3=imm4,min_value=4,max_value=4,min_align=4 R10=fp",
"2: R1=ctx R3=imm8,min_value=8,max_value=8,min_align=4 R10=fp",
"3: R1=ctx R3=imm10,min_value=10,max_value=10,min_align=2 R10=fp",
"4: R1=ctx R3=imm10,min_value=10,max_value=10,min_align=2 R4=imm8,min_value=8,max_value=8,min_align=8 R10=fp",
"5: R1=ctx R3=imm10,min_value=10,max_value=10,min_align=2 R4=imm12,min_value=12,max_value=12,min_align=4 R10=fp",
"6: R1=ctx R3=imm10,min_value=10,max_value=10,min_align=2 R4=imm14,min_value=14,max_value=14,min_align=2 R10=fp",
},
},
{
.descr = "mul",
.insns = {
BPF_MOV64_IMM(BPF_REG_3, 7),
BPF_ALU64_IMM(BPF_MUL, BPF_REG_3, 1),
BPF_ALU64_IMM(BPF_MUL, BPF_REG_3, 2),
BPF_ALU64_IMM(BPF_MUL, BPF_REG_3, 4),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
"1: R1=ctx R3=imm7,min_value=7,max_value=7,min_align=1 R10=fp",
"2: R1=ctx R3=imm7,min_value=7,max_value=7,min_align=1 R10=fp",
"3: R1=ctx R3=imm14,min_value=14,max_value=14,min_align=2 R10=fp",
"4: R1=ctx R3=imm56,min_value=56,max_value=56,min_align=4 R10=fp",
},
},
#define PREP_PKT_POINTERS \
BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, \
offsetof(struct __sk_buff, data)), \
BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, \
offsetof(struct __sk_buff, data_end))
#define LOAD_UNKNOWN(DST_REG) \
PREP_PKT_POINTERS, \
BPF_MOV64_REG(BPF_REG_0, BPF_REG_2), \
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 8), \
BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_0, 1), \
BPF_EXIT_INSN(), \
BPF_LDX_MEM(BPF_B, DST_REG, BPF_REG_2, 0)
{
.descr = "unknown shift",
.insns = {
LOAD_UNKNOWN(BPF_REG_3),
BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1),
BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1),
BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1),
BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1),
LOAD_UNKNOWN(BPF_REG_4),
BPF_ALU64_IMM(BPF_LSH, BPF_REG_4, 5),
BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1),
BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1),
BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1),
BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
"7: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R10=fp",
"8: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv55,min_align=2 R10=fp",
"9: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv54,min_align=4 R10=fp",
"10: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv53,min_align=8 R10=fp",
"11: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv52,min_align=16 R10=fp",
"18: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv56 R10=fp",
"19: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv51,min_align=32 R10=fp",
"20: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv52,min_align=16 R10=fp",
"21: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv53,min_align=8 R10=fp",
"22: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv54,min_align=4 R10=fp",
"23: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv55,min_align=2 R10=fp",
},
},
{
.descr = "unknown mul",
.insns = {
LOAD_UNKNOWN(BPF_REG_3),
BPF_MOV64_REG(BPF_REG_4, BPF_REG_3),
BPF_ALU64_IMM(BPF_MUL, BPF_REG_4, 1),
BPF_MOV64_REG(BPF_REG_4, BPF_REG_3),
BPF_ALU64_IMM(BPF_MUL, BPF_REG_4, 2),
BPF_MOV64_REG(BPF_REG_4, BPF_REG_3),
BPF_ALU64_IMM(BPF_MUL, BPF_REG_4, 4),
BPF_MOV64_REG(BPF_REG_4, BPF_REG_3),
BPF_ALU64_IMM(BPF_MUL, BPF_REG_4, 8),
BPF_ALU64_IMM(BPF_MUL, BPF_REG_4, 2),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
"7: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R10=fp",
"8: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv56 R10=fp",
"9: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv55,min_align=1 R10=fp",
"10: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv56 R10=fp",
"11: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv54,min_align=2 R10=fp",
"12: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv56 R10=fp",
"13: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv53,min_align=4 R10=fp",
"14: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv56 R10=fp",
"15: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv52,min_align=8 R10=fp",
"16: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv50,min_align=8 R10=fp"
},
},
{
.descr = "packet const offset",
.insns = {
PREP_PKT_POINTERS,
BPF_MOV64_REG(BPF_REG_5, BPF_REG_2),
BPF_MOV64_IMM(BPF_REG_0, 0),
/* Skip over ethernet header. */
BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, 14),
BPF_MOV64_REG(BPF_REG_4, BPF_REG_5),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4),
BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_4, 1),
BPF_EXIT_INSN(),
BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_5, 0),
BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_5, 1),
BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_5, 2),
BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_5, 3),
BPF_LDX_MEM(BPF_H, BPF_REG_4, BPF_REG_5, 0),
BPF_LDX_MEM(BPF_H, BPF_REG_4, BPF_REG_5, 2),
BPF_LDX_MEM(BPF_W, BPF_REG_4, BPF_REG_5, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
"4: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R5=pkt(id=0,off=0,r=0) R10=fp",
"5: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R5=pkt(id=0,off=14,r=0) R10=fp",
"6: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R4=pkt(id=0,off=14,r=0) R5=pkt(id=0,off=14,r=0) R10=fp",
"10: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=18) R3=pkt_end R4=inv56 R5=pkt(id=0,off=14,r=18) R10=fp",
"14: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=18) R3=pkt_end R4=inv48 R5=pkt(id=0,off=14,r=18) R10=fp",
"15: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=18) R3=pkt_end R4=inv48 R5=pkt(id=0,off=14,r=18) R10=fp",
},
},
{
.descr = "packet variable offset",
.insns = {
LOAD_UNKNOWN(BPF_REG_6),
BPF_ALU64_IMM(BPF_LSH, BPF_REG_6, 2),
/* First, add a constant to the R5 packet pointer,
* then a variable with a known alignment.
*/
BPF_MOV64_REG(BPF_REG_5, BPF_REG_2),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, 14),
BPF_ALU64_REG(BPF_ADD, BPF_REG_5, BPF_REG_6),
BPF_MOV64_REG(BPF_REG_4, BPF_REG_5),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4),
BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_4, 1),
BPF_EXIT_INSN(),
BPF_LDX_MEM(BPF_W, BPF_REG_4, BPF_REG_5, 0),
/* Now, test in the other direction. Adding first
* the variable offset to R5, then the constant.
*/
BPF_MOV64_REG(BPF_REG_5, BPF_REG_2),
BPF_ALU64_REG(BPF_ADD, BPF_REG_5, BPF_REG_6),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, 14),
BPF_MOV64_REG(BPF_REG_4, BPF_REG_5),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4),
BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_4, 1),
BPF_EXIT_INSN(),
BPF_LDX_MEM(BPF_W, BPF_REG_4, BPF_REG_5, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
/* Calculated offset in R6 has unknown value, but known
* alignment of 4.
*/
"8: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R6=inv54,min_align=4 R10=fp",
/* Offset is added to packet pointer R5, resulting in known
* auxiliary alignment and offset.
*/
"11: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R5=pkt(id=1,off=0,r=0),aux_off=14,aux_off_align=4 R6=inv54,min_align=4 R10=fp",
/* At the time the word size load is performed from R5,
* it's total offset is NET_IP_ALIGN + reg->off (0) +
* reg->aux_off (14) which is 16. Then the variable
* offset is considered using reg->aux_off_align which
* is 4 and meets the load's requirements.
*/
"15: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=pkt(id=1,off=4,r=4),aux_off=14,aux_off_align=4 R5=pkt(id=1,off=0,r=4),aux_off=14,aux_off_align=4 R6=inv54,min_align=4 R10=fp",
/* Variable offset is added to R5 packet pointer,
* resulting in auxiliary alignment of 4.
*/
"18: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv,aux_off=14,aux_off_align=4 R5=pkt(id=2,off=0,r=0),aux_off_align=4 R6=inv54,min_align=4 R10=fp",
/* Constant offset is added to R5, resulting in
* reg->off of 14.
*/
"19: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv,aux_off=14,aux_off_align=4 R5=pkt(id=2,off=14,r=0),aux_off_align=4 R6=inv54,min_align=4 R10=fp",
/* At the time the word size load is performed from R5,
* it's total offset is NET_IP_ALIGN + reg->off (14) which
* is 16. Then the variable offset is considered using
* reg->aux_off_align which is 4 and meets the load's
* requirements.
*/
"23: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=pkt(id=2,off=18,r=18),aux_off_align=4 R5=pkt(id=2,off=14,r=18),aux_off_align=4 R6=inv54,min_align=4 R10=fp",
},
},
};
static int probe_filter_length(const struct bpf_insn *fp)
{
int len;
for (len = MAX_INSNS - 1; len > 0; --len)
if (fp[len].code != 0 || fp[len].imm != 0)
break;
return len + 1;
}
static char bpf_vlog[32768];
static int do_test_single(struct bpf_align_test *test)
{
struct bpf_insn *prog = test->insns;
int prog_type = test->prog_type;
int prog_len, i;
int fd_prog;
int ret;
prog_len = probe_filter_length(prog);
fd_prog = bpf_verify_program(prog_type ? : BPF_PROG_TYPE_SOCKET_FILTER,
prog, prog_len, 1, "GPL", 0,
bpf_vlog, sizeof(bpf_vlog));
if (fd_prog < 0) {
printf("Failed to load program.\n");
printf("%s", bpf_vlog);
ret = 1;
} else {
ret = 0;
for (i = 0; i < MAX_MATCHES; i++) {
const char *t, *m = test->matches[i];
if (!m)
break;
t = strstr(bpf_vlog, m);
if (!t) {
printf("Failed to find match: %s\n", m);
ret = 1;
printf("%s", bpf_vlog);
break;
}
}
close(fd_prog);
}
return ret;
}
static int do_test(unsigned int from, unsigned int to)
{
int all_pass = 0;
int all_fail = 0;
unsigned int i;
for (i = from; i < to; i++) {
struct bpf_align_test *test = &tests[i];
int fail;
printf("Test %3d: %s ... ",
i, test->descr);
fail = do_test_single(test);
if (fail) {
all_fail++;
printf("FAIL\n");
} else {
all_pass++;
printf("PASS\n");
}
}
printf("Results: %d pass %d fail\n",
all_pass, all_fail);
return 0;
}
int main(int argc, char **argv)
{
unsigned int from = 0, to = ARRAY_SIZE(tests);
if (argc == 3) {
unsigned int l = atoi(argv[argc - 2]);
unsigned int u = atoi(argv[argc - 1]);
if (l < to && u < to) {
from = l;
to = u + 1;
}
} else if (argc == 2) {
unsigned int t = atoi(argv[argc - 1]);
if (t < to) {
from = t;
to = t + 1;
}
}
return do_test(from, to);
}
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