Commit b5b5eca9 authored by David S. Miller's avatar David S. Miller

Merge branch 'bpf-support-for-sockets'

David Ahern says:

====================
net: Add bpf support for sockets

The recently added VRF support in Linux leverages the bind-to-device
API for programs to specify an L3 domain for a socket. While
SO_BINDTODEVICE has been around for ages, not every ipv4/ipv6 capable
program has support for it. Even for those programs that do support it,
the API requires processes to be started as root (CAP_NET_RAW) which
is not desirable from a general security perspective.

This patch set leverages Daniel Mack's work to attach bpf programs to
a cgroup to provide a capability to set sk_bound_dev_if for all
AF_INET{6} sockets opened by a process in a cgroup when the sockets
are allocated.

For example:
 1. configure vrf (e.g., using ifupdown2)
        auto eth0
        iface eth0 inet dhcp
            vrf mgmt

        auto mgmt
        iface mgmt
            vrf-table auto

 2. configure cgroup
        mount -t cgroup2 none /tmp/cgroupv2
        mkdir /tmp/cgroupv2/mgmt
        test_cgrp2_sock /tmp/cgroupv2/mgmt 15

 3. set shell into cgroup (e.g., can be done at login using pam)
        echo $$ >> /tmp/cgroupv2/mgmt/cgroup.procs

At this point all commands run in the shell (e.g, apt) have sockets
automatically bound to the VRF (see output of ss -ap 'dev == <vrf>'),
including processes not running as root.

This capability enables running any program in a VRF context and is key
to deploying Management VRF, a fundamental configuration for networking
gear, with any Linux OS installation.

This patchset also exports the socket family, type and protocol as
read-only allowing bpf filters to deny a process in a cgroup the ability
to open specific types of AF_INET or AF_INET6 sockets.

v7
- comments from Alexei

v6
- add export of socket family, type and protocol
====================
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 7f7bf160 554ae6e7
......@@ -36,31 +36,44 @@ void cgroup_bpf_update(struct cgroup *cgrp,
struct bpf_prog *prog,
enum bpf_attach_type type);
int __cgroup_bpf_run_filter(struct sock *sk,
struct sk_buff *skb,
enum bpf_attach_type type);
/* Wrappers for __cgroup_bpf_run_filter() guarded by cgroup_bpf_enabled. */
#define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk,skb) \
({ \
int __ret = 0; \
if (cgroup_bpf_enabled) \
__ret = __cgroup_bpf_run_filter(sk, skb, \
BPF_CGROUP_INET_INGRESS); \
\
__ret; \
int __cgroup_bpf_run_filter_skb(struct sock *sk,
struct sk_buff *skb,
enum bpf_attach_type type);
int __cgroup_bpf_run_filter_sk(struct sock *sk,
enum bpf_attach_type type);
/* Wrappers for __cgroup_bpf_run_filter_skb() guarded by cgroup_bpf_enabled. */
#define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb) \
({ \
int __ret = 0; \
if (cgroup_bpf_enabled) \
__ret = __cgroup_bpf_run_filter_skb(sk, skb, \
BPF_CGROUP_INET_INGRESS); \
\
__ret; \
})
#define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk,skb) \
({ \
int __ret = 0; \
if (cgroup_bpf_enabled && sk && sk == skb->sk) { \
typeof(sk) __sk = sk_to_full_sk(sk); \
if (sk_fullsock(__sk)) \
__ret = __cgroup_bpf_run_filter(__sk, skb, \
BPF_CGROUP_INET_EGRESS); \
} \
__ret; \
#define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk, skb) \
({ \
int __ret = 0; \
if (cgroup_bpf_enabled && sk && sk == skb->sk) { \
typeof(sk) __sk = sk_to_full_sk(sk); \
if (sk_fullsock(__sk)) \
__ret = __cgroup_bpf_run_filter_skb(__sk, skb, \
BPF_CGROUP_INET_EGRESS); \
} \
__ret; \
})
#define BPF_CGROUP_RUN_PROG_INET_SOCK(sk) \
({ \
int __ret = 0; \
if (cgroup_bpf_enabled && sk) { \
__ret = __cgroup_bpf_run_filter_sk(sk, \
BPF_CGROUP_INET_SOCK_CREATE); \
} \
__ret; \
})
#else
......@@ -72,6 +85,7 @@ static inline void cgroup_bpf_inherit(struct cgroup *cgrp,
#define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk,skb) ({ 0; })
#define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk,skb) ({ 0; })
#define BPF_CGROUP_RUN_PROG_INET_SOCK(sk) ({ 0; })
#endif /* CONFIG_CGROUP_BPF */
......
......@@ -389,6 +389,21 @@ struct sock {
* Because of non atomicity rules, all
* changes are protected by socket lock.
*/
unsigned int __sk_flags_offset[0];
#ifdef __BIG_ENDIAN_BITFIELD
#define SK_FL_PROTO_SHIFT 16
#define SK_FL_PROTO_MASK 0x00ff0000
#define SK_FL_TYPE_SHIFT 0
#define SK_FL_TYPE_MASK 0x0000ffff
#else
#define SK_FL_PROTO_SHIFT 8
#define SK_FL_PROTO_MASK 0x0000ff00
#define SK_FL_TYPE_SHIFT 16
#define SK_FL_TYPE_MASK 0xffff0000
#endif
kmemcheck_bitfield_begin(flags);
unsigned int sk_padding : 2,
sk_no_check_tx : 1,
......
......@@ -101,6 +101,7 @@ enum bpf_prog_type {
BPF_PROG_TYPE_XDP,
BPF_PROG_TYPE_PERF_EVENT,
BPF_PROG_TYPE_CGROUP_SKB,
BPF_PROG_TYPE_CGROUP_SOCK,
BPF_PROG_TYPE_LWT_IN,
BPF_PROG_TYPE_LWT_OUT,
BPF_PROG_TYPE_LWT_XMIT,
......@@ -109,6 +110,7 @@ enum bpf_prog_type {
enum bpf_attach_type {
BPF_CGROUP_INET_INGRESS,
BPF_CGROUP_INET_EGRESS,
BPF_CGROUP_INET_SOCK_CREATE,
__MAX_BPF_ATTACH_TYPE
};
......@@ -567,6 +569,13 @@ enum bpf_ret_code {
/* >127 are reserved for prog type specific return codes */
};
struct bpf_sock {
__u32 bound_dev_if;
__u32 family;
__u32 type;
__u32 protocol;
};
/* User return codes for XDP prog type.
* A valid XDP program must return one of these defined values. All other
* return codes are reserved for future use. Unknown return codes will result
......
......@@ -118,7 +118,7 @@ void __cgroup_bpf_update(struct cgroup *cgrp,
}
/**
* __cgroup_bpf_run_filter() - Run a program for packet filtering
* __cgroup_bpf_run_filter_skb() - Run a program for packet filtering
* @sk: The socken sending or receiving traffic
* @skb: The skb that is being sent or received
* @type: The type of program to be exectuted
......@@ -132,9 +132,9 @@ void __cgroup_bpf_update(struct cgroup *cgrp,
* This function will return %-EPERM if any if an attached program was found
* and if it returned != 1 during execution. In all other cases, 0 is returned.
*/
int __cgroup_bpf_run_filter(struct sock *sk,
struct sk_buff *skb,
enum bpf_attach_type type)
int __cgroup_bpf_run_filter_skb(struct sock *sk,
struct sk_buff *skb,
enum bpf_attach_type type)
{
struct bpf_prog *prog;
struct cgroup *cgrp;
......@@ -164,4 +164,37 @@ int __cgroup_bpf_run_filter(struct sock *sk,
return ret;
}
EXPORT_SYMBOL(__cgroup_bpf_run_filter);
EXPORT_SYMBOL(__cgroup_bpf_run_filter_skb);
/**
* __cgroup_bpf_run_filter_sk() - Run a program on a sock
* @sk: sock structure to manipulate
* @type: The type of program to be exectuted
*
* socket is passed is expected to be of type INET or INET6.
*
* The program type passed in via @type must be suitable for sock
* filtering. No further check is performed to assert that.
*
* This function will return %-EPERM if any if an attached program was found
* and if it returned != 1 during execution. In all other cases, 0 is returned.
*/
int __cgroup_bpf_run_filter_sk(struct sock *sk,
enum bpf_attach_type type)
{
struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
struct bpf_prog *prog;
int ret = 0;
rcu_read_lock();
prog = rcu_dereference(cgrp->bpf.effective[type]);
if (prog)
ret = BPF_PROG_RUN(prog, sk) == 1 ? 0 : -EPERM;
rcu_read_unlock();
return ret;
}
EXPORT_SYMBOL(__cgroup_bpf_run_filter_sk);
......@@ -856,6 +856,7 @@ static int bpf_prog_attach(const union bpf_attr *attr)
{
struct bpf_prog *prog;
struct cgroup *cgrp;
enum bpf_prog_type ptype;
if (!capable(CAP_NET_ADMIN))
return -EPERM;
......@@ -866,25 +867,28 @@ static int bpf_prog_attach(const union bpf_attr *attr)
switch (attr->attach_type) {
case BPF_CGROUP_INET_INGRESS:
case BPF_CGROUP_INET_EGRESS:
prog = bpf_prog_get_type(attr->attach_bpf_fd,
BPF_PROG_TYPE_CGROUP_SKB);
if (IS_ERR(prog))
return PTR_ERR(prog);
cgrp = cgroup_get_from_fd(attr->target_fd);
if (IS_ERR(cgrp)) {
bpf_prog_put(prog);
return PTR_ERR(cgrp);
}
cgroup_bpf_update(cgrp, prog, attr->attach_type);
cgroup_put(cgrp);
ptype = BPF_PROG_TYPE_CGROUP_SKB;
break;
case BPF_CGROUP_INET_SOCK_CREATE:
ptype = BPF_PROG_TYPE_CGROUP_SOCK;
break;
default:
return -EINVAL;
}
prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
if (IS_ERR(prog))
return PTR_ERR(prog);
cgrp = cgroup_get_from_fd(attr->target_fd);
if (IS_ERR(cgrp)) {
bpf_prog_put(prog);
return PTR_ERR(cgrp);
}
cgroup_bpf_update(cgrp, prog, attr->attach_type);
cgroup_put(cgrp);
return 0;
}
......@@ -903,6 +907,7 @@ static int bpf_prog_detach(const union bpf_attr *attr)
switch (attr->attach_type) {
case BPF_CGROUP_INET_INGRESS:
case BPF_CGROUP_INET_EGRESS:
case BPF_CGROUP_INET_SOCK_CREATE:
cgrp = cgroup_get_from_fd(attr->target_fd);
if (IS_ERR(cgrp))
return PTR_ERR(cgrp);
......
......@@ -2818,6 +2818,32 @@ static bool lwt_is_valid_access(int off, int size,
return __is_valid_access(off, size, type);
}
static bool sock_filter_is_valid_access(int off, int size,
enum bpf_access_type type,
enum bpf_reg_type *reg_type)
{
if (type == BPF_WRITE) {
switch (off) {
case offsetof(struct bpf_sock, bound_dev_if):
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 tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write,
const struct bpf_prog *prog)
{
......@@ -3076,6 +3102,51 @@ static u32 sk_filter_convert_ctx_access(enum bpf_access_type type, int dst_reg,
return insn - insn_buf;
}
static u32 sock_filter_convert_ctx_access(enum bpf_access_type type,
int dst_reg, int src_reg,
int ctx_off,
struct bpf_insn *insn_buf,
struct bpf_prog *prog)
{
struct bpf_insn *insn = insn_buf;
switch (ctx_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, dst_reg, src_reg,
offsetof(struct sock, sk_bound_dev_if));
else
*insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
offsetof(struct sock, sk_bound_dev_if));
break;
case offsetof(struct bpf_sock, family):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_family) != 2);
*insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
offsetof(struct sock, sk_family));
break;
case offsetof(struct bpf_sock, type):
*insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
offsetof(struct sock, __sk_flags_offset));
*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, SK_FL_TYPE_MASK);
*insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, SK_FL_TYPE_SHIFT);
break;
case offsetof(struct bpf_sock, protocol):
*insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
offsetof(struct sock, __sk_flags_offset));
*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, SK_FL_PROTO_MASK);
*insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, SK_FL_PROTO_SHIFT);
break;
}
return insn - insn_buf;
}
static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type, int dst_reg,
int src_reg, int ctx_off,
struct bpf_insn *insn_buf,
......@@ -3162,6 +3233,12 @@ static const struct bpf_verifier_ops lwt_xmit_ops = {
.gen_prologue = tc_cls_act_prologue,
};
static const struct bpf_verifier_ops cg_sock_ops = {
.get_func_proto = sk_filter_func_proto,
.is_valid_access = sock_filter_is_valid_access,
.convert_ctx_access = sock_filter_convert_ctx_access,
};
static struct bpf_prog_type_list sk_filter_type __read_mostly = {
.ops = &sk_filter_ops,
.type = BPF_PROG_TYPE_SOCKET_FILTER,
......@@ -3202,6 +3279,11 @@ static struct bpf_prog_type_list lwt_xmit_type __read_mostly = {
.type = BPF_PROG_TYPE_LWT_XMIT,
};
static struct bpf_prog_type_list cg_sock_type __read_mostly = {
.ops = &cg_sock_ops,
.type = BPF_PROG_TYPE_CGROUP_SOCK
};
static int __init register_sk_filter_ops(void)
{
bpf_register_prog_type(&sk_filter_type);
......@@ -3209,6 +3291,7 @@ static int __init register_sk_filter_ops(void)
bpf_register_prog_type(&sched_act_type);
bpf_register_prog_type(&xdp_type);
bpf_register_prog_type(&cg_skb_type);
bpf_register_prog_type(&cg_sock_type);
bpf_register_prog_type(&lwt_in_type);
bpf_register_prog_type(&lwt_out_type);
bpf_register_prog_type(&lwt_xmit_type);
......
......@@ -374,8 +374,18 @@ static int inet_create(struct net *net, struct socket *sock, int protocol,
if (sk->sk_prot->init) {
err = sk->sk_prot->init(sk);
if (err)
if (err) {
sk_common_release(sk);
goto out;
}
}
if (!kern) {
err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
if (err) {
sk_common_release(sk);
goto out;
}
}
out:
return err;
......
......@@ -258,6 +258,14 @@ static int inet6_create(struct net *net, struct socket *sock, int protocol,
goto out;
}
}
if (!kern) {
err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
if (err) {
sk_common_release(sk);
goto out;
}
}
out:
return err;
out_rcu_unlock:
......
......@@ -23,6 +23,8 @@ hostprogs-y += map_perf_test
hostprogs-y += test_overhead
hostprogs-y += test_cgrp2_array_pin
hostprogs-y += test_cgrp2_attach
hostprogs-y += test_cgrp2_sock
hostprogs-y += test_cgrp2_sock2
hostprogs-y += xdp1
hostprogs-y += xdp2
hostprogs-y += test_current_task_under_cgroup
......@@ -52,6 +54,8 @@ map_perf_test-objs := bpf_load.o libbpf.o map_perf_test_user.o
test_overhead-objs := bpf_load.o libbpf.o test_overhead_user.o
test_cgrp2_array_pin-objs := libbpf.o test_cgrp2_array_pin.o
test_cgrp2_attach-objs := libbpf.o test_cgrp2_attach.o
test_cgrp2_sock-objs := libbpf.o test_cgrp2_sock.o
test_cgrp2_sock2-objs := bpf_load.o libbpf.o test_cgrp2_sock2.o
xdp1-objs := bpf_load.o libbpf.o xdp1_user.o
# reuse xdp1 source intentionally
xdp2-objs := bpf_load.o libbpf.o xdp1_user.o
......@@ -73,6 +77,7 @@ always += tracex3_kern.o
always += tracex4_kern.o
always += tracex5_kern.o
always += tracex6_kern.o
always += sock_flags_kern.o
always += test_probe_write_user_kern.o
always += trace_output_kern.o
always += tcbpf1_kern.o
......@@ -107,6 +112,7 @@ HOSTLOADLIBES_tracex3 += -lelf
HOSTLOADLIBES_tracex4 += -lelf -lrt
HOSTLOADLIBES_tracex5 += -lelf
HOSTLOADLIBES_tracex6 += -lelf
HOSTLOADLIBES_test_cgrp2_sock2 += -lelf
HOSTLOADLIBES_test_probe_write_user += -lelf
HOSTLOADLIBES_trace_output += -lelf -lrt
HOSTLOADLIBES_lathist += -lelf
......
......@@ -52,6 +52,8 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
bool is_tracepoint = strncmp(event, "tracepoint/", 11) == 0;
bool is_xdp = strncmp(event, "xdp", 3) == 0;
bool is_perf_event = strncmp(event, "perf_event", 10) == 0;
bool is_cgroup_skb = strncmp(event, "cgroup/skb", 10) == 0;
bool is_cgroup_sk = strncmp(event, "cgroup/sock", 11) == 0;
enum bpf_prog_type prog_type;
char buf[256];
int fd, efd, err, id;
......@@ -72,6 +74,10 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
prog_type = BPF_PROG_TYPE_XDP;
} else if (is_perf_event) {
prog_type = BPF_PROG_TYPE_PERF_EVENT;
} else if (is_cgroup_skb) {
prog_type = BPF_PROG_TYPE_CGROUP_SKB;
} else if (is_cgroup_sk) {
prog_type = BPF_PROG_TYPE_CGROUP_SOCK;
} else {
printf("Unknown event '%s'\n", event);
return -1;
......@@ -85,7 +91,7 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
prog_fd[prog_cnt++] = fd;
if (is_xdp || is_perf_event)
if (is_xdp || is_perf_event || is_cgroup_skb || is_cgroup_sk)
return 0;
if (is_socket) {
......@@ -334,7 +340,8 @@ int load_bpf_file(char *path)
memcmp(shname_prog, "tracepoint/", 11) == 0 ||
memcmp(shname_prog, "xdp", 3) == 0 ||
memcmp(shname_prog, "perf_event", 10) == 0 ||
memcmp(shname_prog, "socket", 6) == 0)
memcmp(shname_prog, "socket", 6) == 0 ||
memcmp(shname_prog, "cgroup/", 7) == 0)
load_and_attach(shname_prog, insns, data_prog->d_size);
}
}
......@@ -353,7 +360,8 @@ int load_bpf_file(char *path)
memcmp(shname, "tracepoint/", 11) == 0 ||
memcmp(shname, "xdp", 3) == 0 ||
memcmp(shname, "perf_event", 10) == 0 ||
memcmp(shname, "socket", 6) == 0)
memcmp(shname, "socket", 6) == 0 ||
memcmp(shname, "cgroup/", 7) == 0)
load_and_attach(shname, data->d_buf, data->d_size);
}
......
......@@ -7,6 +7,7 @@
extern int map_fd[MAX_MAPS];
extern int prog_fd[MAX_PROGS];
extern int event_fd[MAX_PROGS];
extern int prog_cnt;
/* parses elf file compiled by llvm .c->.o
* . parses 'maps' section and creates maps via BPF syscall
......
#include <uapi/linux/bpf.h>
#include <linux/socket.h>
#include <linux/net.h>
#include <uapi/linux/in.h>
#include <uapi/linux/in6.h>
#include "bpf_helpers.h"
SEC("cgroup/sock1")
int bpf_prog1(struct bpf_sock *sk)
{
char fmt[] = "socket: family %d type %d protocol %d\n";
bpf_trace_printk(fmt, sizeof(fmt), sk->family, sk->type, sk->protocol);
/* block PF_INET6, SOCK_RAW, IPPROTO_ICMPV6 sockets
* ie., make ping6 fail
*/
if (sk->family == PF_INET6 &&
sk->type == SOCK_RAW &&
sk->protocol == IPPROTO_ICMPV6)
return 0;
return 1;
}
SEC("cgroup/sock2")
int bpf_prog2(struct bpf_sock *sk)
{
char fmt[] = "socket: family %d type %d protocol %d\n";
bpf_trace_printk(fmt, sizeof(fmt), sk->family, sk->type, sk->protocol);
/* block PF_INET, SOCK_RAW, IPPROTO_ICMP sockets
* ie., make ping fail
*/
if (sk->family == PF_INET &&
sk->type == SOCK_RAW &&
sk->protocol == IPPROTO_ICMP)
return 0;
return 1;
}
char _license[] SEC("license") = "GPL";
/* eBPF example program:
*
* - Loads eBPF program
*
* The eBPF program sets the sk_bound_dev_if index in new AF_INET{6}
* sockets opened by processes in the cgroup.
*
* - Attaches the new program to a cgroup using BPF_PROG_ATTACH
*/
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <unistd.h>
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <net/if.h>
#include <linux/bpf.h>
#include "libbpf.h"
static int prog_load(int idx)
{
struct bpf_insn prog[] = {
BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
BPF_MOV64_IMM(BPF_REG_3, idx),
BPF_MOV64_IMM(BPF_REG_2, offsetof(struct bpf_sock, bound_dev_if)),
BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_3, offsetof(struct bpf_sock, bound_dev_if)),
BPF_MOV64_IMM(BPF_REG_0, 1), /* r0 = verdict */
BPF_EXIT_INSN(),
};
return bpf_prog_load(BPF_PROG_TYPE_CGROUP_SOCK, prog, sizeof(prog),
"GPL", 0);
}
static int usage(const char *argv0)
{
printf("Usage: %s cg-path device-index\n", argv0);
return EXIT_FAILURE;
}
int main(int argc, char **argv)
{
int cg_fd, prog_fd, ret;
unsigned int idx;
if (argc < 2)
return usage(argv[0]);
idx = if_nametoindex(argv[2]);
if (!idx) {
printf("Invalid device name\n");
return EXIT_FAILURE;
}
cg_fd = open(argv[1], O_DIRECTORY | O_RDONLY);
if (cg_fd < 0) {
printf("Failed to open cgroup path: '%s'\n", strerror(errno));
return EXIT_FAILURE;
}
prog_fd = prog_load(idx);
printf("Output from kernel verifier:\n%s\n-------\n", bpf_log_buf);
if (prog_fd < 0) {
printf("Failed to load prog: '%s'\n", strerror(errno));
return EXIT_FAILURE;
}
ret = bpf_prog_attach(prog_fd, cg_fd, BPF_CGROUP_INET_SOCK_CREATE);
if (ret < 0) {
printf("Failed to attach prog to cgroup: '%s'\n",
strerror(errno));
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}
#!/bin/bash
function config_device {
ip netns add at_ns0
ip link add veth0 type veth peer name veth0b
ip link set veth0b up
ip link set veth0 netns at_ns0
ip netns exec at_ns0 ip addr add 172.16.1.100/24 dev veth0
ip netns exec at_ns0 ip addr add 2401:db00::1/64 dev veth0 nodad
ip netns exec at_ns0 ip link set dev veth0 up
ip link add foo type vrf table 1234
ip link set foo up
ip addr add 172.16.1.101/24 dev veth0b
ip addr add 2401:db00::2/64 dev veth0b nodad
ip link set veth0b master foo
}
function attach_bpf {
rm -rf /tmp/cgroupv2
mkdir -p /tmp/cgroupv2
mount -t cgroup2 none /tmp/cgroupv2
mkdir -p /tmp/cgroupv2/foo
test_cgrp2_sock /tmp/cgroupv2/foo foo
echo $$ >> /tmp/cgroupv2/foo/cgroup.procs
}
function cleanup {
set +ex
ip netns delete at_ns0
ip link del veth0
ip link del foo
umount /tmp/cgroupv2
rm -rf /tmp/cgroupv2
set -ex
}
function do_test {
ping -c1 -w1 172.16.1.100
ping6 -c1 -w1 2401:db00::1
}
cleanup 2>/dev/null
config_device
attach_bpf
do_test
cleanup
echo "*** PASS ***"
/* eBPF example program:
*
* - Loads eBPF program
*
* The eBPF program loads a filter from file and attaches the
* program to a cgroup using BPF_PROG_ATTACH
*/
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <unistd.h>
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <net/if.h>
#include <linux/bpf.h>
#include "libbpf.h"
#include "bpf_load.h"
static int usage(const char *argv0)
{
printf("Usage: %s cg-path filter-path [filter-id]\n", argv0);
return EXIT_FAILURE;
}
int main(int argc, char **argv)
{
int cg_fd, ret, filter_id = 0;
if (argc < 3)
return usage(argv[0]);
cg_fd = open(argv[1], O_DIRECTORY | O_RDONLY);
if (cg_fd < 0) {
printf("Failed to open cgroup path: '%s'\n", strerror(errno));
return EXIT_FAILURE;
}
if (load_bpf_file(argv[2]))
return EXIT_FAILURE;
printf("Output from kernel verifier:\n%s\n-------\n", bpf_log_buf);
if (argc > 3)
filter_id = atoi(argv[3]);
if (filter_id > prog_cnt) {
printf("Invalid program id; program not found in file\n");
return EXIT_FAILURE;
}
ret = bpf_prog_attach(prog_fd[filter_id], cg_fd,
BPF_CGROUP_INET_SOCK_CREATE);
if (ret < 0) {
printf("Failed to attach prog to cgroup: '%s'\n",
strerror(errno));
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}
#!/bin/bash
function config_device {
ip netns add at_ns0
ip link add veth0 type veth peer name veth0b
ip link set veth0b up
ip link set veth0 netns at_ns0
ip netns exec at_ns0 ip addr add 172.16.1.100/24 dev veth0
ip netns exec at_ns0 ip addr add 2401:db00::1/64 dev veth0 nodad
ip netns exec at_ns0 ip link set dev veth0 up
ip addr add 172.16.1.101/24 dev veth0b
ip addr add 2401:db00::2/64 dev veth0b nodad
}
function config_cgroup {
rm -rf /tmp/cgroupv2
mkdir -p /tmp/cgroupv2
mount -t cgroup2 none /tmp/cgroupv2
mkdir -p /tmp/cgroupv2/foo
echo $$ >> /tmp/cgroupv2/foo/cgroup.procs
}
function attach_bpf {
test_cgrp2_sock2 /tmp/cgroupv2/foo sock_flags_kern.o $1
[ $? -ne 0 ] && exit 1
}
function cleanup {
ip link del veth0b
ip netns delete at_ns0
umount /tmp/cgroupv2
rm -rf /tmp/cgroupv2
}
cleanup 2>/dev/null
set -e
config_device
config_cgroup
set +e
#
# Test 1 - fail ping6
#
attach_bpf 0
ping -c1 -w1 172.16.1.100
if [ $? -ne 0 ]; then
echo "ping failed when it should succeed"
cleanup
exit 1
fi
ping6 -c1 -w1 2401:db00::1
if [ $? -eq 0 ]; then
echo "ping6 succeeded when it should not"
cleanup
exit 1
fi
#
# Test 2 - fail ping
#
attach_bpf 1
ping6 -c1 -w1 2401:db00::1
if [ $? -ne 0 ]; then
echo "ping6 failed when it should succeed"
cleanup
exit 1
fi
ping -c1 -w1 172.16.1.100
if [ $? -eq 0 ]; then
echo "ping succeeded when it should not"
cleanup
exit 1
fi
cleanup
echo
echo "*** PASS ***"
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment