glebfm/strace
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

bpf: implement decoding of prog_name and prog_ifindex fields

Browse Source 
* bpf.c (BEGIN_BPF_CMD_DECODER(BPF_PROG_LOAD)): Add support for decoding
of prog_name (introduced in Linux commit v4.15-rc1~84^2~605^2~4) and
prog_ifindex (introduced as prog_target_ifindex in v4.15-rc1~84^2~127^2~13,
renamed in v4.15-rc1~15^2~5^2~3^2~7).
* bpf_attr.h [!BPF_OBJ_NAME_LEN] (BPF_OBJ_NAME_LEN): New macro constant.
[BPF_OBJ_NAME_LEN]: Check that BPF_OBJ_NAME_LEN is equal to 16.
(struct BPF_PROG_LOAD_struct): Add prog_name and prog_ifindex fields.
(BPF_PROG_LOAD_struct_size, expected_BPF_PROG_LOAD_struct_size): Update.
* tests/bpf.c (init_BPF_PROG_LOAD_attr): Rename
to init_BPF_PROG_LOAD_attr3.
(print_BPF_PROG_LOAD_attr): Rename to print_BPF_PROG_LOAD_attr3.
(init_BPF_PROG_LOAD_attr4, print_BPF_PROG_LOAD_attr4): New functions.
(BPF_PROG_LOAD_checks): Check new decoding features.
This commit is contained in:
Eugene Syromyatnikov 2018-02-22 03:22:48 +01:00 committed by Dmitry V. Levin
parent a3509bac24
commit cbaa5db24d
3 changed files with 130 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
bpf.c
View File

@ -194,6 +194,23 @@ BEGIN_BPF_CMD_DECODER(BPF_PROG_LOAD)
if (len <= offsetof(struct BPF_PROG_LOAD_struct, prog_flags))
break;
PRINT_FIELD_FLAGS(", ", attr, prog_flags, bpf_prog_flags, "BPF_F_???");
/* prog_name field was added in Linux commit v4.15-rc1~84^2~605^2~4. */
if (len <= offsetof(struct BPF_PROG_LOAD_struct, prog_name))
break;
PRINT_FIELD_CSTRING_SZ(", ", attr, prog_name,
MIN(sizeof(attr.prog_name),
len - offsetof(struct BPF_PROG_LOAD_struct,
prog_name)));
/*
* prog_ifindex field was added as prog_target_ifindex in Linux commit
* v4.15-rc1~84^2~127^2~13 and renamed to its current name in
* v4.15-rc1~15^2~5^2~3^2~7.
*/
if (len <= offsetof(struct BPF_PROG_LOAD_struct, prog_ifindex))
break;
PRINT_FIELD_IFINDEX(", ", attr, prog_ifindex);
}
END_BPF_CMD_DECODER(RVAL_DECODED | RVAL_FD)

14
bpf_attr.h
View File

@ -28,6 +28,14 @@
#ifndef STRACE_BPF_ATTR_H
#define STRACE_BPF_ATTR_H
#ifndef BPF_OBJ_NAME_LEN
# define BPF_OBJ_NAME_LEN 16U
#else
# if BPF_OBJ_NAME_LEN != 16U
# error "Unexpected value of BPF_OBJ_NAME_LEN"
# endif
#endif
struct BPF_MAP_CREATE_struct {
uint32_t map_type;
uint32_t key_size;
@ -92,11 +100,13 @@ struct BPF_PROG_LOAD_struct {
uint64_t ATTRIBUTE_ALIGNED(8) log_buf;
uint32_t kern_version;
uint32_t prog_flags;
char prog_name[BPF_OBJ_NAME_LEN];
uint32_t prog_ifindex;
};
#define BPF_PROG_LOAD_struct_size \
sizeof(struct BPF_PROG_LOAD_struct)
#define expected_BPF_PROG_LOAD_struct_size 48
offsetofend(struct BPF_PROG_LOAD_struct, prog_ifindex)
#define expected_BPF_PROG_LOAD_struct_size 68
struct BPF_OBJ_PIN_struct {
uint64_t ATTRIBUTE_ALIGNED(8) pathname;

113
tests/bpf.c
View File

@ -334,7 +334,7 @@ static char log_buf[4096];
static const char pathname[] = "/sys/fs/bpf/foo/bar";
static void
init_BPF_PROG_LOAD_attr(struct bpf_attr_check *check)
init_BPF_PROG_LOAD_attr3(struct bpf_attr_check *check)
{
struct BPF_PROG_LOAD_struct *attr = &check->data.BPF_PROG_LOAD_data;
attr->insns = (uintptr_t) insns;
@ -343,16 +343,39 @@ init_BPF_PROG_LOAD_attr(struct bpf_attr_check *check)
}
static void
print_BPF_PROG_LOAD_attr(const struct bpf_attr_check *check, unsigned long addr)
print_BPF_PROG_LOAD_attr3(const struct bpf_attr_check *check, unsigned long addr)
{
printf("prog_type=BPF_PROG_TYPE_SOCKET_FILTER, insn_cnt=%u, insns=%p"
", license=\"%s\", log_level=42, log_size=4096, log_buf=%p"
", kern_version=KERNEL_VERSION(51966, 240, 13)"
", prog_flags=BPF_F_STRICT_ALIGNMENT",
", license=\"%s\", log_level=2718281828, log_size=4096"
", log_buf=%p, kern_version=KERNEL_VERSION(51966, 240, 13)"
", prog_flags=0x2 /* BPF_F_??? */"
", prog_name=\"0123456789abcde\"..., prog_ifindex=3203399405",
(unsigned int) ARRAY_SIZE(insns), insns,
license, log_buf);
}
static void
init_BPF_PROG_LOAD_attr4(struct bpf_attr_check *check)
{
struct BPF_PROG_LOAD_struct *attr = &check->data.BPF_PROG_LOAD_data;
attr->insns = (uintptr_t) insns;
attr->license = (uintptr_t) license;
attr->log_buf = (uintptr_t) log_buf;
attr->prog_ifindex = ifindex_lo();
}
static void
print_BPF_PROG_LOAD_attr4(const struct bpf_attr_check *check, unsigned long addr)
{
printf("prog_type=BPF_PROG_TYPE_UNSPEC, insn_cnt=%u, insns=%p"
", license=\"%s\", log_level=2718281828, log_size=4096"
", log_buf=%p, kern_version=KERNEL_VERSION(51966, 240, 13)"
", prog_flags=BPF_F_STRICT_ALIGNMENT|0x2"
", prog_name=\"0123456789abcde\"..., prog_ifindex=%s",
(unsigned int) ARRAY_SIZE(insns), insns,
license, log_buf, IFINDEX_LO_STR);
}
static struct bpf_attr_check BPF_PROG_LOAD_checks[] = {
{
.data = { .BPF_PROG_LOAD_data = { .prog_type = 1 } },
@ -360,19 +383,85 @@ static struct bpf_attr_check BPF_PROG_LOAD_checks[] = {
.str = "prog_type=BPF_PROG_TYPE_SOCKET_FILTER"
", insn_cnt=0, insns=0, license=NULL"
},
{
{ /* 1 */
.data = { .BPF_PROG_LOAD_data = {
.prog_type = 16,
.insn_cnt = 0xbadc0ded,
.insns = 0,
.license = 0,
.log_level = 42,
.log_size = 3141592653U,
.log_buf = 0,
.kern_version = 0xcafef00d,
.prog_flags = 0,
} },
.size = offsetofend(struct BPF_PROG_LOAD_struct, prog_flags),
.str = "prog_type=0x10 /* BPF_PROG_TYPE_??? */"
", insn_cnt=3134983661, insns=0, license=NULL"
", log_level=42, log_size=3141592653, log_buf=0"
", kern_version=KERNEL_VERSION(51966, 240, 13)"
", prog_flags=0",
},
{ /* 2 */
.data = { .BPF_PROG_LOAD_data = {
.prog_type = 15,
.insn_cnt = 0xbadc0ded,
.insns = 0xffffffff00000000,
.license = 0xffffffff00000000,
.log_level = 2718281828U,
.log_size = sizeof(log_buf),
.log_buf = 0xffffffff00000000,
.kern_version = 0xcafef00d,
.prog_flags = 1,
.prog_name = "fedcba987654321",
} },
.size = offsetofend(struct BPF_PROG_LOAD_struct, prog_name),
.str = "prog_type=BPF_PROG_TYPE_CGROUP_DEVICE"
", insn_cnt=3134983661, insns=0xffffffff00000000"
#if defined MPERS_IS_m32 || SIZEOF_KERNEL_LONG_T > 4
", license=0xffffffff00000000"
#elif defined __arm__ || defined __i386__ || defined __mips__ || \
defined __powerpc__ || defined __riscv__ || defined __s390__ \
|| defined __sparc__ || defined __tile__
", license=0xffffffff00000000 or NULL"
#else
", license=NULL"
#endif
", log_level=2718281828, log_size=4096"
", log_buf=0xffffffff00000000"
", kern_version=KERNEL_VERSION(51966, 240, 13)"
", prog_flags=BPF_F_STRICT_ALIGNMENT"
", prog_name=\"fedcba987654321\"",
},
{ /* 3 */
.data = { .BPF_PROG_LOAD_data = {
.prog_type = 1,
.insn_cnt = ARRAY_SIZE(insns),
.log_level = 42,
.log_level = 2718281828U,
.log_size = sizeof(log_buf),
.kern_version = 0xcafef00d,
.prog_flags = 1
.prog_flags = 2,
.prog_name = "0123456789abcdef",
.prog_ifindex = 0xbeeffeed,
} },
.size = offsetofend(struct BPF_PROG_LOAD_struct, prog_flags),
.init_fn = init_BPF_PROG_LOAD_attr,
.print_fn = print_BPF_PROG_LOAD_attr
}
.size = offsetofend(struct BPF_PROG_LOAD_struct, prog_ifindex),
.init_fn = init_BPF_PROG_LOAD_attr3,
.print_fn = print_BPF_PROG_LOAD_attr3
},
{ /* 4 */
.data = { .BPF_PROG_LOAD_data = {
.prog_type = 0,
.insn_cnt = ARRAY_SIZE(insns),
.log_level = 2718281828U,
.log_size = sizeof(log_buf),
.kern_version = 0xcafef00d,
.prog_flags = 3,
.prog_name = "0123456789abcdef",
} },
.size = offsetofend(struct BPF_PROG_LOAD_struct, prog_ifindex),
.init_fn = init_BPF_PROG_LOAD_attr4,
.print_fn = print_BPF_PROG_LOAD_attr4
},
};
static void