// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2018 Facebook
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <sys/select.h>
#include <sys/socket.h>
#include <linux/filter.h>
#include <bpf/bpf.h>
#include <bpf/libbpf.h>
#include "cgroup_helpers.h"
#include "bpf_rlimit.h"
#include "bpf_util.h"
#ifndef ENOTSUPP
# define ENOTSUPP 524
#endif
#define CG_PATH "/foo"
#define CONNECT4_PROG_PATH "./connect4_prog.o"
#define CONNECT6_PROG_PATH "./connect6_prog.o"
#define SENDMSG4_PROG_PATH "./sendmsg4_prog.o"
#define SENDMSG6_PROG_PATH "./sendmsg6_prog.o"
#define SERV4_IP "192.168.1.254"
#define SERV4_REWRITE_IP "127.0.0.1"
#define SRC4_IP "172.16.0.1"
#define SRC4_REWRITE_IP "127.0.0.4"
#define SERV4_PORT 4040
#define SERV4_REWRITE_PORT 4444
#define SERV6_IP "face:b00c:1234:5678::abcd"
#define SERV6_REWRITE_IP "::1"
#define SERV6_V4MAPPED_IP "::ffff:192.168.0.4"
#define SRC6_IP "::1"
#define SRC6_REWRITE_IP "::6"
#define SERV6_PORT 6060
#define SERV6_REWRITE_PORT 6666
#define INET_NTOP_BUF 40
struct sock_addr_test;
typedef int (*load_fn)(const struct sock_addr_test *test);
typedef int (*info_fn)(int, struct sockaddr *, socklen_t *);
char bpf_log_buf[BPF_LOG_BUF_SIZE];
struct sock_addr_test {
const char *descr;
/* BPF prog properties */
load_fn loadfn;
enum bpf_attach_type expected_attach_type;
enum bpf_attach_type attach_type;
/* Socket properties */
int domain;
int type;
/* IP:port pairs for BPF prog to override */
const char *requested_ip;
unsigned short requested_port;
const char *expected_ip;
unsigned short expected_port;
const char *expected_src_ip;
/* Expected test result */
enum {
LOAD_REJECT,
ATTACH_REJECT,
SYSCALL_EPERM,
SYSCALL_ENOTSUPP,
SUCCESS,
} expected_result;
};
static int bind4_prog_load(const struct sock_addr_test *test);
static int bind6_prog_load(const struct sock_addr_test *test);
static int connect4_prog_load(const struct sock_addr_test *test);
static int connect6_prog_load(const struct sock_addr_test *test);
static int sendmsg_deny_prog_load(const struct sock_addr_test *test);
static int sendmsg4_rw_asm_prog_load(const struct sock_addr_test *test);
static int sendmsg4_rw_c_prog_load(const struct sock_addr_test *test);
static int sendmsg6_rw_asm_prog_load(const struct sock_addr_test *test);
static int sendmsg6_rw_c_prog_load(const struct sock_addr_test *test);
static int sendmsg6_rw_v4mapped_prog_load(const struct sock_addr_test *test);
static struct sock_addr_test tests[] = {
/* bind */
{
"bind4: load prog with wrong expected attach type",
bind4_prog_load,
BPF_CGROUP_INET6_BIND,
BPF_CGROUP_INET4_BIND,
AF_INET,
SOCK_STREAM,
NULL,
0,
NULL,
0,
NULL,
LOAD_REJECT,
},
{
"bind4: attach prog with wrong attach type",
bind4_prog_load,
BPF_CGROUP_INET4_BIND,
BPF_CGROUP_INET6_BIND,
AF_INET,
SOCK_STREAM,
NULL,
0,
NULL,
0,
NULL,
ATTACH_REJECT,
},
{
"bind4: rewrite IP & TCP port in",
bind4_prog_load,
BPF_CGROUP_INET4_BIND,
BPF_CGROUP_INET4_BIND,
AF_INET,
SOCK_STREAM,
SERV4_IP,
SERV4_PORT,
SERV4_REWRITE_IP,
SERV4_REWRITE_PORT,
NULL,
SUCCESS,
},
{
"bind4: rewrite IP & UDP port in",
bind4_prog_load,
BPF_CGROUP_INET4_BIND,
BPF_CGROUP_INET4_BIND,
AF_INET,
SOCK_DGRAM,
SERV4_IP,
SERV4_PORT,
SERV4_REWRITE_IP,
SERV4_REWRITE_PORT,
NULL,
SUCCESS,
},
{
"bind6: load prog with wrong expected attach type",
bind6_prog_load,
BPF_CGROUP_INET4_BIND,
BPF_CGROUP_INET6_BIND,
AF_INET6,
SOCK_STREAM,
NULL,
0,
NULL,
0,
NULL,
LOAD_REJECT,
},
{
"bind6: attach prog with wrong attach type",
bind6_prog_load,
BPF_CGROUP_INET6_BIND,
BPF_CGROUP_INET4_BIND,
AF_INET,
SOCK_STREAM,
NULL,
0,
NULL,
0,
NULL,
ATTACH_REJECT,
},
{
"bind6: rewrite IP & TCP port in",
bind6_prog_load,
BPF_CGROUP_INET6_BIND,
BPF_CGROUP_INET6_BIND,
AF_INET6,
SOCK_STREAM,
SERV6_IP,
SERV6_PORT,
SERV6_REWRITE_IP,
SERV6_REWRITE_PORT,
NULL,
SUCCESS,
},
{
"bind6: rewrite IP & UDP port in",
bind6_prog_load,
BPF_CGROUP_INET6_BIND,
BPF_CGROUP_INET6_BIND,
AF_INET6,
SOCK_DGRAM,
SERV6_IP,
SERV6_PORT,
SERV6_REWRITE_IP,
SERV6_REWRITE_PORT,
NULL,
SUCCESS,
},
/* connect */
{
"connect4: load prog with wrong expected attach type",
connect4_prog_load,
BPF_CGROUP_INET6_CONNECT,
BPF_CGROUP_INET4_CONNECT,
AF_INET,
SOCK_STREAM,
NULL,
0,
NULL,
0,
NULL,
LOAD_REJECT,
},
{
"connect4: attach prog with wrong attach type",
connect4_prog_load,
BPF_CGROUP_INET4_CONNECT,
BPF_CGROUP_INET6_CONNECT,
AF_INET,
SOCK_STREAM,
NULL,
0,
NULL,
0,
NULL,
ATTACH_REJECT,
},
{
"connect4: rewrite IP & TCP port",
connect4_prog_load,
BPF_CGROUP_INET4_CONNECT,
BPF_CGROUP_INET4_CONNECT,
AF_INET,
SOCK_STREAM,
SERV4_IP,
SERV4_PORT,
SERV4_REWRITE_IP,
SERV4_REWRITE_PORT,
SRC4_REWRITE_IP,
SUCCESS,
},
{
"connect4: rewrite IP & UDP port",
connect4_prog_load,
BPF_CGROUP_INET4_CONNECT,
BPF_CGROUP_INET4_CONNECT,
AF_INET,
SOCK_DGRAM,
SERV4_IP,
SERV4_PORT,
SERV4_REWRITE_IP,
SERV4_REWRITE_PORT,
SRC4_REWRITE_IP,
SUCCESS,
},
{
"connect6: load prog with wrong expected attach type",
connect6_prog_load,
BPF_CGROUP_INET4_CONNECT,
BPF_CGROUP_INET6_CONNECT,
AF_INET6,
SOCK_STREAM,
NULL,
0,
NULL,
0,
NULL,
LOAD_REJECT,
},
{
"connect6: attach prog with wrong attach type",
connect6_prog_load,
BPF_CGROUP_INET6_CONNECT,
BPF_CGROUP_INET4_CONNECT,
AF_INET,
SOCK_STREAM,
NULL,
0,
NULL,
0,
NULL,
ATTACH_REJECT,
},
{
"connect6: rewrite IP & TCP port",
connect6_prog_load,
BPF_CGROUP_INET6_CONNECT,
BPF_CGROUP_INET6_CONNECT,
AF_INET6,
SOCK_STREAM,
SERV6_IP,
SERV6_PORT,
SERV6_REWRITE_IP,
SERV6_REWRITE_PORT,
SRC6_REWRITE_IP,
SUCCESS,
},
{
"connect6: rewrite IP & UDP port",
connect6_prog_load,
BPF_CGROUP_INET6_CONNECT,
BPF_CGROUP_INET6_CONNECT,
AF_INET6,
SOCK_DGRAM,
SERV6_IP,
SERV6_PORT,
SERV6_REWRITE_IP,
SERV6_REWRITE_PORT,
SRC6_REWRITE_IP,
SUCCESS,
},
/* sendmsg */
{
"sendmsg4: load prog with wrong expected attach type",
sendmsg4_rw_asm_prog_load,
BPF_CGROUP_UDP6_SENDMSG,
BPF_CGROUP_UDP4_SENDMSG,
AF_INET,
SOCK_DGRAM,
NULL,
0,
NULL,
0,
NULL,
LOAD_REJECT,
},
{
"sendmsg4: attach prog with wrong attach type",
sendmsg4_rw_asm_prog_load,
BPF_CGROUP_UDP4_SENDMSG,
BPF_CGROUP_UDP6_SENDMSG,
AF_INET,
SOCK_DGRAM,
NULL,
0,
NULL,
0,
NULL,
ATTACH_REJECT,
},
{
"sendmsg4: rewrite IP & port (asm)",
sendmsg4_rw_asm_prog_load,
BPF_CGROUP_UDP4_SENDMSG,
BPF_CGROUP_UDP4_SENDMSG,
AF_INET,
SOCK_DGRAM,
SERV4_IP,
SERV4_PORT,
SERV4_REWRITE_IP,
SERV4_REWRITE_PORT,
SRC4_REWRITE_IP,
SUCCESS,
},
{
"sendmsg4: rewrite IP & port (C)",
sendmsg4_rw_c_prog_load,
BPF_CGROUP_UDP4_SENDMSG,
BPF_CGROUP_UDP4_SENDMSG,
AF_INET,
SOCK_DGRAM,
SERV4_IP,
SERV4_PORT,
SERV4_REWRITE_IP,
SERV4_REWRITE_PORT,
SRC4_REWRITE_IP,
SUCCESS,
},
{
"sendmsg4: deny call",
sendmsg_deny_prog_load,
BPF_CGROUP_UDP4_SENDMSG,
BPF_CGROUP_UDP4_SENDMSG,
AF_INET,
SOCK_DGRAM,
SERV4_IP,
SERV4_PORT,
SERV4_REWRITE_IP,
SERV4_REWRITE_PORT,
SRC4_REWRITE_IP,
SYSCALL_EPERM,
},
{
"sendmsg6: load prog with wrong expected attach type",
sendmsg6_rw_asm_prog_load,
BPF_CGROUP_UDP4_SENDMSG,
BPF_CGROUP_UDP6_SENDMSG,
AF_INET6,
SOCK_DGRAM,
NULL,
0,
NULL,
0,
NULL,
LOAD_REJECT,
},
{
"sendmsg6: attach prog with wrong attach type",
sendmsg6_rw_asm_prog_load,
BPF_CGROUP_UDP6_SENDMSG,
BPF_CGROUP_UDP4_SENDMSG,
AF_INET6,
SOCK_DGRAM,
NULL,
0,
NULL,
0,
NULL,
ATTACH_REJECT,
},
{
"sendmsg6: rewrite IP & port (asm)",
sendmsg6_rw_asm_prog_load,
BPF_CGROUP_UDP6_SENDMSG,
BPF_CGROUP_UDP6_SENDMSG,
AF_INET6,
SOCK_DGRAM,
SERV6_IP,
SERV6_PORT,
SERV6_REWRITE_IP,
SERV6_REWRITE_PORT,
SRC6_REWRITE_IP,
SUCCESS,
},
{
"sendmsg6: rewrite IP & port (C)",
sendmsg6_rw_c_prog_load,
BPF_CGROUP_UDP6_SENDMSG,
BPF_CGROUP_UDP6_SENDMSG,
AF_INET6,
SOCK_DGRAM,
SERV6_IP,
SERV6_PORT,
SERV6_REWRITE_IP,
SERV6_REWRITE_PORT,
SRC6_REWRITE_IP,
SUCCESS,
},
{
"sendmsg6: IPv4-mapped IPv6",
sendmsg6_rw_v4mapped_prog_load,
BPF_CGROUP_UDP6_SENDMSG,
BPF_CGROUP_UDP6_SENDMSG,
AF_INET6,
SOCK_DGRAM,
SERV6_IP,
SERV6_PORT,
SERV6_REWRITE_IP,
SERV6_REWRITE_PORT,
SRC6_REWRITE_IP,
SYSCALL_ENOTSUPP,
},
{
"sendmsg6: deny call",
sendmsg_deny_prog_load,
BPF_CGROUP_UDP6_SENDMSG,
BPF_CGROUP_UDP6_SENDMSG,
AF_INET6,
SOCK_DGRAM,
SERV6_IP,
SERV6_PORT,
SERV6_REWRITE_IP,
SERV6_REWRITE_PORT,
SRC6_REWRITE_IP,
SYSCALL_EPERM,
},
};
static int mk_sockaddr(int domain, const char *ip, unsigned short port,
struct sockaddr *addr, socklen_t addr_len)
{
struct sockaddr_in6 *addr6;
struct sockaddr_in *addr4;
if (domain != AF_INET && domain != AF_INET6) {
log_err("Unsupported address family");
return -1;
}
memset(addr, 0, addr_len);
if (domain == AF_INET) {
if (addr_len < sizeof(struct sockaddr_in))
return -1;
addr4 = (struct sockaddr_in *)addr;
addr4->sin_family = domain;
addr4->sin_port = htons(port);
if (inet_pton(domain, ip, (void *)&addr4->sin_addr) != 1) {
log_err("Invalid IPv4: %s", ip);
return -1;
}
} else if (domain == AF_INET6) {
if (addr_len < sizeof(struct sockaddr_in6))
return -1;
addr6 = (struct sockaddr_in6 *)addr;
addr6->sin6_family = domain;
addr6->sin6_port = htons(port);
if (inet_pton(domain, ip, (void *)&addr6->sin6_addr) != 1) {
log_err("Invalid IPv6: %s", ip);
return -1;
}
}
return 0;
}
static int load_insns(const struct sock_addr_test *test,
const struct bpf_insn *insns, size_t insns_cnt)
{
struct bpf_load_program_attr load_attr;
int ret;
memset(&load_attr, 0, sizeof(struct bpf_load_program_attr));
load_attr.prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
load_attr.expected_attach_type = test->expected_attach_type;
load_attr.insns = insns;
load_attr.insns_cnt = insns_cnt;
load_attr.license = "GPL";
ret = bpf_load_program_xattr(&load_attr, bpf_log_buf, BPF_LOG_BUF_SIZE);
if (ret < 0 && test->expected_result != LOAD_REJECT) {
log_err(">>> Loading program error.\n"
">>> Verifier output:\n%s\n-------\n", bpf_log_buf);
}
return ret;
}
/* [1] These testing programs try to read different context fields, including
* narrow loads of different sizes from user_ip4 and user_ip6, and write to
* those allowed to be overridden.
*
* [2] BPF_LD_IMM64 & BPF_JMP_REG are used below whenever there is a need to
* compare a register with unsigned 32bit integer. BPF_JMP_IMM can't be used
* in such cases since it accepts only _signed_ 32bit integer as IMM
* argument. Also note that BPF_LD_IMM64 contains 2 instructions what matters
* to count jumps properly.
*/
static int bind4_prog_load(const struct sock_addr_test *test)
{
union {
uint8_t u4_addr8[4];
uint16_t u4_addr16[2];
uint32_t u4_addr32;
} ip4;
struct sockaddr_in addr4_rw;
if (inet_pton(AF_INET, SERV4_IP, (void *)&ip4) != 1) {
log_err("Invalid IPv4: %s", SERV4_IP);
return -1;
}
if (mk_sockaddr(AF_INET, SERV4_REWRITE_IP, SERV4_REWRITE_PORT,
(struct sockaddr *)&addr4_rw, sizeof(addr4_rw)) == -1)
return -1;
/* See [1]. */
struct bpf_insn insns[] = {
BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
/* if (sk.family == AF_INET && */
BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
offsetof(struct bpf_sock_addr, family)),
BPF_JMP_IMM(BPF_JNE, BPF_REG_7, AF_INET, 16),
/* (sk.type == SOCK_DGRAM || sk.type == SOCK_STREAM) && */
BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
offsetof(struct bpf_sock_addr, type)),
BPF_JMP_IMM(BPF_JNE, BPF_REG_7, SOCK_DGRAM, 1),
BPF_JMP_A(1),
BPF_JMP_IMM(BPF_JNE, BPF_REG_7, SOCK_STREAM, 12),
/* 1st_byte_of_user_ip4 == expected && */
BPF_LDX_MEM(BPF_B, BPF_REG_7, BPF_REG_6,
offsetof(struct bpf_sock_addr, user_ip4)),
BPF_JMP_IMM(BPF_JNE, BPF_REG_7, ip4.u4_addr8[0], 10),
/* 1st_half_of_user_ip4 == expected && */
BPF_LDX_MEM(BPF_H, BPF_REG_7, BPF_REG_6,
offsetof(struct bpf_sock_addr, user_ip4)),
BPF_JMP_IMM(BPF_JNE, BPF_REG_7, ip4.u4_addr16[0], 8),
/* whole_user_ip4 == expected) { */
BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
offsetof(struct bpf_sock_addr, user_ip4)),
BPF_LD_IMM64(BPF_REG_8, ip4.u4_addr32), /* See [2]. */
BPF_JMP_REG(BPF_JNE, BPF_REG_7, BPF_REG_8, 4),
/* user_ip4 = addr4_rw.sin_addr */
BPF_MOV32_IMM(BPF_REG_7, addr4_rw.sin_addr.s_addr),
BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7,
offsetof(struct bpf_sock_addr, user_ip4)),
/* user_port = addr4_rw.sin_port */
BPF_MOV32_IMM(BPF_REG_7, addr4_rw.sin_port),
BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7,
offsetof(struct bpf_sock_addr, user_port)),
/* } */
/* return 1 */
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_EXIT_INSN(),
};
return load_insns(test, insns, sizeof(insns) / sizeof(struct bpf_insn));
}
static int bind6_prog_load(const struct sock_addr_test *test)
{
struct sockaddr_in6 addr6_rw;
struct in6_addr ip6;
if (inet_pton(AF_INET6, SERV6_IP, (void *)&ip6) != 1) {
log_err("Invalid IPv6: %s", SERV6_IP);
return -1;
}
if (mk_sockaddr(AF_INET6, SERV6_REWRITE_IP, SERV6_REWRITE_PORT,
(struct sockaddr *)&addr6_rw, sizeof(addr6_rw)) == -1)
return -1;
/* See [1]. */
struct bpf_insn insns[] = {
BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
/* if (sk.family == AF_INET6 && */
BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
offsetof(struct bpf_sock_addr, family)),
BPF_JMP_IMM(BPF_JNE, BPF_REG_7, AF_INET6, 18),
/* 5th_byte_of_user_ip6 == expected && */
BPF_LDX_MEM(BPF_B, BPF_REG_7, BPF_REG_6,
offsetof(struct bpf_sock_addr, user_ip6[1])),
BPF_JMP_IMM(BPF_JNE, BPF_REG_7, ip6.s6_addr[4], 16),
/* 3rd_half_of_user_ip6 == expected && */
BPF_LDX_MEM(BPF_H, BPF_REG_7, BPF_REG_6,
offsetof(struct bpf_sock_addr, user_ip6[1])),
BPF_JMP_IMM(BPF_JNE, BPF_REG_7, ip6.s6_addr16[2], 14),
/* last_word_of_user_ip6 == expected) { */
BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
offsetof(struct bpf_sock_addr, user_ip6[3])),
BPF_LD_IMM64(BPF_REG_8, ip6.s6_addr32[3]), /* See [2]. */
BPF_JMP_REG(BPF_JNE, BPF_REG_7, BPF_REG_8, 10),
#define STORE_IPV6_WORD(N) \
BPF_MOV32_IMM(BPF_REG_7, addr6_rw.sin6_addr.s6_addr32[N]), \
BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7, \
offsetof(struct bpf_sock_addr, user_ip6[N]))
/* user_ip6 = addr6_rw.sin6_addr */
STORE_IPV6_WORD(0),
STORE_IPV6_WORD(1),
STORE_IPV6_WORD(2),
STORE_IPV6_WORD(3),
/* user_port = addr6_rw.sin6_port */
BPF_MOV32_IMM(BPF_REG_7, addr6_rw.sin6_port),
BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7,
offsetof(struct bpf_sock_addr, user_port)),
/* } */
/* return 1 */
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_EXIT_INSN(),
};
return load_insns(test, insns, sizeof(insns) / sizeof(struct bpf_insn));
}
static int load_path(const struct sock_addr_test *test, const char *path)
{
struct bpf_prog_load_attr attr;
struct bpf_object *obj;
int prog_fd;
memset(&attr, 0, sizeof(struct bpf_prog_load_attr));
attr.file = path;
attr.prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
attr.expected_attach_type = test->expected_attach_type;
if (bpf_prog_load_xattr(&attr, &obj, &prog_fd)) {
if (test->expected_result != LOAD_REJECT)
log_err(">>> Loading program (%s) error.\n", path);
return -1;
}
return prog_fd;
}
static int connect4_prog_load(const struct sock_addr_test *test)
{
return load_path(test, CONNECT4_PROG_PATH);
}
static int connect6_prog_load(const struct sock_addr_test *test)
{
return load_path(test, CONNECT6_PROG_PATH);
}
static int sendmsg_deny_prog_load(const struct sock_addr_test *test)
{
struct bpf_insn insns[] = {
/* return 0 */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
};
return load_insns(test, insns, sizeof(insns) / sizeof(struct bpf_insn));
}
static int sendmsg4_rw_asm_prog_load(const struct sock_addr_test *test)
{
struct sockaddr_in dst4_rw_addr;
struct in_addr src4_rw_ip;
if (inet_pton(AF_INET, SRC4_REWRITE_IP, (void *)&src4_rw_ip) != 1) {
log_err("Invalid IPv4: %s", SRC4_REWRITE_IP);
return -1;
}
if (mk_sockaddr(AF_INET, SERV4_REWRITE_IP, SERV4_REWRITE_PORT,
(struct sockaddr *)&dst4_rw_addr,
sizeof(dst4_rw_addr)) == -1)
return -1;
struct bpf_insn insns[] = {
BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
/* if (sk.family == AF_INET && */
BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
offsetof(struct bpf_sock_addr, family)),
BPF_JMP_IMM(BPF_JNE, BPF_REG_7, AF_INET, 8),
/* sk.type == SOCK_DGRAM) { */
BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
offsetof(struct bpf_sock_addr, type)),
BPF_JMP_IMM(BPF_JNE, BPF_REG_7, SOCK_DGRAM, 6),
/* msg_src_ip4 = src4_rw_ip */
BPF_MOV32_IMM(BPF_REG_7, src4_rw_ip.s_addr),
BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7,
offsetof(struct bpf_sock_addr, msg_src_ip4)),
/* user_ip4 = dst4_rw_addr.sin_addr */
BPF_MOV32_IMM(BPF_REG_7, dst4_rw_addr.sin_addr.s_addr),
BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7,
offsetof(struct bpf_sock_addr, user_ip4)),
/* user_port = dst4_rw_addr.sin_port */
BPF_MOV32_IMM(BPF_REG_7, dst4_rw_addr.sin_port),
BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7,
offsetof(struct bpf_sock_addr, user_port)),
/* } */
/* return 1 */
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_EXIT_INSN(),
};
return load_insns(test, insns, sizeof(insns) / sizeof(struct bpf_insn));
}
static int sendmsg4_rw_c_prog_load(const struct sock_addr_test *test)
{
return load_path(test, SENDMSG4_PROG_PATH);
}
static int sendmsg6_rw_dst_asm_prog_load(const struct sock_addr_test *test,
const char *rw_dst_ip)
{
struct sockaddr_in6 dst6_rw_addr;
struct in6_addr src6_rw_ip;
if (inet_pton(AF_INET6, SRC6_REWRITE_IP, (void *)&src6_rw_ip) != 1) {
log_err("Invalid IPv6: %s", SRC6_REWRITE_IP);
return -1;
}
if (mk_sockaddr(AF_INET6, rw_dst_ip, SERV6_REWRITE_PORT,
(struct sockaddr *)&dst6_rw_addr,
sizeof(dst6_rw_addr)) == -1)
return -1;
struct bpf_insn insns[] = {
BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
/* if (sk.family == AF_INET6) { */
BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
offsetof(struct bpf_sock_addr, family)),
BPF_JMP_IMM(BPF_JNE, BPF_REG_7, AF_INET6, 18),
#define STORE_IPV6_WORD_N(DST, SRC, N) \
BPF_MOV32_IMM(BPF_REG_7, SRC[N]), \
BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7, \
offsetof(struct bpf_sock_addr, DST[N]))
#define STORE_IPV6(DST, SRC) \
STORE_IPV6_WORD_N(DST, SRC, 0), \
STORE_IPV6_WORD_N(DST, SRC, 1), \
STORE_IPV6_WORD_N(DST, SRC, 2), \
STORE_IPV6_WORD_N(DST, SRC, 3)
STORE_IPV6(msg_src_ip6, src6_rw_ip.s6_addr32),
STORE_IPV6(user_ip6, dst6_rw_addr.sin6_addr.s6_addr32),
/* user_port = dst6_rw_addr.sin6_port */
BPF_MOV32_IMM(BPF_REG_7, dst6_rw_addr.sin6_port),
BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7,
offsetof(struct bpf_sock_addr, user_port)),
/* } */
/* return 1 */
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_EXIT_INSN(),
};
return load_insns(test, insns, sizeof(insns) / sizeof(struct bpf_insn));
}
static int sendmsg6_rw_asm_prog_load(const struct sock_addr_test *test)
{
return sendmsg6_rw_dst_asm_prog_load(test, SERV6_REWRITE_IP);
}
static int sendmsg6_rw_v4mapped_prog_load(const struct sock_addr_test *test)
{
return sendmsg6_rw_dst_asm_prog_load(test, SERV6_V4MAPPED_IP);
}
static int sendmsg6_rw_c_prog_load(const struct sock_addr_test *test)
{
return load_path(test, SENDMSG6_PROG_PATH);
}
static int cmp_addr(const struct sockaddr_storage *addr1,
const struct sockaddr_storage *addr2, int cmp_port)
{
const struct sockaddr_in *four1, *four2;
const struct sockaddr_in6 *six1, *six2;
if (addr1->ss_family != addr2->ss_family)
return -1;
if (addr1->ss_family == AF_INET) {
four1 = (const struct sockaddr_in *)addr1;
four2 = (const struct sockaddr_in *)addr2;
return !((four1->sin_port == four2->sin_port || !cmp_port) &&
four1->sin_addr.s_addr == four2->sin_addr.s_addr);
} else if (addr1->ss_family == AF_INET6) {
six1 = (const struct sockaddr_in6 *)addr1;
six2 = (const struct sockaddr_in6 *)addr2;
return !((six1->sin6_port == six2->sin6_port || !cmp_port) &&
!memcmp(&six1->sin6_addr, &six2->sin6_addr,
sizeof(struct in6_addr)));
}
return -1;
}
static int cmp_sock_addr(info_fn fn, int sock1,
const struct sockaddr_storage *addr2, int cmp_port)
{
struct sockaddr_storage addr1;
socklen_t len1 = sizeof(addr1);
memset(&addr1, 0, len1);
if (fn(sock1, (struct sockaddr *)&addr1, (socklen_t *)&len1) != 0)
return -1;
return cmp_addr(&addr1, addr2, cmp_port);
}
static int cmp_local_ip(int sock1, const struct sockaddr_storage *addr2)
{
return cmp_sock_addr(getsockname, sock1, addr2, /*cmp_port*/ 0);
}
static int cmp_local_addr(int sock1, const struct sockaddr_storage *addr2)
{
return cmp_sock_addr(getsockname, sock1, addr2, /*cmp_port*/ 1);
}
static int cmp_peer_addr(int sock1, const struct sockaddr_storage *addr2)
{
return cmp_sock_addr(getpeername, sock1, addr2, /*cmp_port*/ 1);
}
static int start_server(int type, const struct sockaddr_storage *addr,
socklen_t addr_len)
{
int fd;
fd = socket(addr->ss_family, type, 0);
if (fd == -1) {
log_err("Failed to create server socket");
goto out;
}
if (bind(fd, (const struct sockaddr *)addr, addr_len) == -1) {
log_err("Failed to bind server socket");
goto close_out;
}
if (type == SOCK_STREAM) {
if (listen(fd, 128) == -1) {
log_err("Failed to listen on server socket");
goto close_out;
}
}
goto out;
close_out:
close(fd);
fd = -1;
out:
return fd;
}
static int connect_to_server(int type, const struct sockaddr_storage *addr,
socklen_t addr_len)
{
int domain;
int fd = -1;
domain = addr->ss_family;
if (domain != AF_INET && domain != AF_INET6) {
log_err("Unsupported address family");
goto err;
}
fd = socket(domain, type, 0);
if (fd == -1) {
log_err("Failed to create client socket");
goto err;
}
if (connect(fd, (const struct sockaddr *)addr, addr_len) == -1) {
log_err("Fail to connect to server");
goto err;
}
goto out;
err:
close(fd);
fd = -1;
out:
return fd;
}
int init_pktinfo(int domain, struct cmsghdr *cmsg)
{
struct in6_pktinfo *pktinfo6;
struct in_pktinfo *pktinfo4;
if (domain == AF_INET) {
cmsg->cmsg_level = SOL_IP;
cmsg->cmsg_type = IP_PKTINFO;
cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_pktinfo));
pktinfo4 = (struct in_pktinfo *)CMSG_DATA(cmsg);
memset(pktinfo4, 0, sizeof(struct in_pktinfo));
if (inet_pton(domain, SRC4_IP,
(void *)&pktinfo4->ipi_spec_dst) != 1)
return -1;
} else if (domain == AF_INET6) {
cmsg->cmsg_level = SOL_IPV6;
cmsg->cmsg_type = IPV6_PKTINFO;
cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
pktinfo6 = (struct in6_pktinfo *)CMSG_DATA(cmsg);
memset(pktinfo6, 0, sizeof(struct in6_pktinfo));
if (inet_pton(domain, SRC6_IP,
(void *)&pktinfo6->ipi6_addr) != 1)
return -1;
} else {
return -1;
}
return 0;
}
static int sendmsg_to_server(int type, const struct sockaddr_storage *addr,
socklen_t addr_len, int set_cmsg, int flags,
int *syscall_err)
{
union {
char buf[CMSG_SPACE(sizeof(struct in6_pktinfo))];
struct cmsghdr align;
} control6;
union {
char buf[CMSG_SPACE(sizeof(struct in_pktinfo))];
struct cmsghdr align;
} control4;
struct msghdr hdr;
struct iovec iov;
char data = 'a';
int domain;
int fd = -1;
domain = addr->ss_family;
if (domain != AF_INET && domain != AF_INET6) {
log_err("Unsupported address family");
goto err;
}
fd = socket(domain, type, 0);
if (fd == -1) {
log_err("Failed to create client socket");
goto err;
}
memset(&iov, 0, sizeof(iov));
iov.iov_base = &data;
iov.iov_len = sizeof(data);
memset(&hdr, 0, sizeof(hdr));
hdr.msg_name = (void *)addr;
hdr.msg_namelen = addr_len;
hdr.msg_iov = &iov;
hdr.msg_iovlen = 1;
if (set_cmsg) {
if (domain == AF_INET) {
hdr.msg_control = &control4;
hdr.msg_controllen = sizeof(control4.buf);
} else if (domain == AF_INET6) {
hdr.msg_control = &control6;
hdr.msg_controllen = sizeof(control6.buf);
}
if (init_pktinfo(domain, CMSG_FIRSTHDR(&hdr))) {
log_err("Fail to init pktinfo");
goto err;
}
}
if (sendmsg(fd, &hdr, flags) != sizeof(data)) {
log_err("Fail to send message to server");
*syscall_err = errno;
goto err;
}
goto out;
err:
close(fd);
fd = -1;
out:
return fd;
}
static int fastconnect_to_server(const struct sockaddr_storage *addr,
socklen_t addr_len)
{
int sendmsg_err;
return sendmsg_to_server(SOCK_STREAM, addr, addr_len, /*set_cmsg*/0,
MSG_FASTOPEN, &sendmsg_err);
}
static int recvmsg_from_client(int sockfd, struct sockaddr_storage *src_addr)
{
struct timeval tv;
struct msghdr hdr;
struct iovec iov;
char data[64];
fd_set rfds;
FD_ZERO(&rfds);
FD_SET(sockfd, &rfds);
tv.tv_sec = 2;
tv.tv_usec = 0;
if (select(sockfd + 1, &rfds, NULL, NULL, &tv) <= 0 ||
!FD_ISSET(sockfd, &rfds))
return -1;
memset(&iov, 0, sizeof(iov));
iov.iov_base = data;
iov.iov_len = sizeof(data);
memset(&hdr, 0, sizeof(hdr));
hdr.msg_name = src_addr;
hdr.msg_namelen = sizeof(struct sockaddr_storage);
hdr.msg_iov = &iov;
hdr.msg_iovlen = 1;
return recvmsg(sockfd, &hdr, 0);
}
static int init_addrs(const struct sock_addr_test *test,
struct sockaddr_storage *requested_addr,
struct sockaddr_storage *expected_addr,
struct sockaddr_storage *expected_src_addr)
{
socklen_t addr_len = sizeof(struct sockaddr_storage);
if (mk_sockaddr(test->domain, test->expected_ip, test->expected_port,
(struct sockaddr *)expected_addr, addr_len) == -1)
goto err;
if (mk_sockaddr(test->domain, test->requested_ip, test->requested_port,
(struct sockaddr *)requested_addr, addr_len) == -1)
goto err;
if (test->expected_src_ip &&
mk_sockaddr(test->domain, test->expected_src_ip, 0,
(struct sockaddr *)expected_src_addr, addr_len) == -1)
goto err;
return 0;
err:
return -1;
}
static int run_bind_test_case(const struct sock_addr_test *test)
{
socklen_t addr_len = sizeof(struct sockaddr_storage);
struct sockaddr_storage requested_addr;
struct sockaddr_storage expected_addr;
int clientfd = -1;
int servfd = -1;
int err = 0;
if (init_addrs(test, &requested_addr, &expected_addr, NULL))
goto err;
servfd = start_server(test->type, &requested_addr, addr_len);
if (servfd == -1)
goto err;
if (cmp_local_addr(servfd, &expected_addr))
goto err;
/* Try to connect to server just in case */
clientfd = connect_to_server(test->type, &expected_addr, addr_len);
if (clientfd == -1)
goto err;
goto out;
err:
err = -1;
out:
close(clientfd);
close(servfd);
return err;
}
static int run_connect_test_case(const struct sock_addr_test *test)
{
socklen_t addr_len = sizeof(struct sockaddr_storage);
struct sockaddr_storage expected_src_addr;
struct sockaddr_storage requested_addr;
struct sockaddr_storage expected_addr;
int clientfd = -1;
int servfd = -1;
int err = 0;
if (init_addrs(test, &requested_addr, &expected_addr,
&expected_src_addr))
goto err;
/* Prepare server to connect to */
servfd = start_server(test->type, &expected_addr, addr_len);
if (servfd == -1)
goto err;
clientfd = connect_to_server(test->type, &requested_addr, addr_len);
if (clientfd == -1)
goto err;
/* Make sure src and dst addrs were overridden properly */
if (cmp_peer_addr(clientfd, &expected_addr))
goto err;
if (cmp_local_ip(clientfd, &expected_src_addr))
goto err;
if (test->type == SOCK_STREAM) {
/* Test TCP Fast Open scenario */
clientfd = fastconnect_to_server(&requested_addr, addr_len);
if (clientfd == -1)
goto err;
/* Make sure src and dst addrs were overridden properly */
if (cmp_peer_addr(clientfd, &expected_addr))
goto err;
if (cmp_local_ip(clientfd, &expected_src_addr))
goto err;
}
goto out;
err:
err = -1;
out:
close(clientfd);
close(servfd);
return err;
}
static int run_sendmsg_test_case(const struct sock_addr_test *test)
{
socklen_t addr_len = sizeof(struct sockaddr_storage);
struct sockaddr_storage expected_src_addr;
struct sockaddr_storage requested_addr;
struct sockaddr_storage expected_addr;
struct sockaddr_storage real_src_addr;
int clientfd = -1;
int servfd = -1;
int set_cmsg;
int err = 0;
if (test->type != SOCK_DGRAM)
goto err;
if (init_addrs(test, &requested_addr, &expected_addr,
&expected_src_addr))
goto err;
/* Prepare server to sendmsg to */
servfd = start_server(test->type, &expected_addr, addr_len);
if (servfd == -1)
goto err;
for (set_cmsg = 0; set_cmsg <= 1; ++set_cmsg) {
if (clientfd >= 0)
close(clientfd);
clientfd = sendmsg_to_server(test->type, &requested_addr,
addr_len, set_cmsg, /*flags*/0,
&err);
if (err)
goto out;
else if (clientfd == -1)
goto err;
/* Try to receive message on server instead of using
* getpeername(2) on client socket, to check that client's
* destination address was rewritten properly, since
* getpeername(2) doesn't work with unconnected datagram
* sockets.
*
* Get source address from recvmsg(2) as well to make sure
* source was rewritten properly: getsockname(2) can't be used
* since socket is unconnected and source defined for one
* specific packet may differ from the one used by default and
* returned by getsockname(2).
*/
if (recvmsg_from_client(servfd, &real_src_addr) == -1)
goto err;
if (cmp_addr(&real_src_addr, &expected_src_addr, /*cmp_port*/0))
goto err;
}
goto out;
err:
err = -1;
out:
close(clientfd);
close(servfd);
return err;
}
static int run_test_case(int cgfd, const struct sock_addr_test *test)
{
int progfd = -1;
int err = 0;
printf("Test case: %s .. ", test->descr);
progfd = test->loadfn(test);
if (test->expected_result == LOAD_REJECT && progfd < 0)
goto out;
else if (test->expected_result == LOAD_REJECT || progfd < 0)
goto err;
err = bpf_prog_attach(progfd, cgfd, test->attach_type,
BPF_F_ALLOW_OVERRIDE);
if (test->expected_result == ATTACH_REJECT && err) {
err = 0; /* error was expected, reset it */
goto out;
} else if (test->expected_result == ATTACH_REJECT || err) {
goto err;
}
switch (test->attach_type) {
case BPF_CGROUP_INET4_BIND:
case BPF_CGROUP_INET6_BIND:
err = run_bind_test_case(test);
break;
case BPF_CGROUP_INET4_CONNECT:
case BPF_CGROUP_INET6_CONNECT:
err = run_connect_test_case(test);
break;
case BPF_CGROUP_UDP4_SENDMSG:
case BPF_CGROUP_UDP6_SENDMSG:
err = run_sendmsg_test_case(test);
break;
default:
goto err;
}
if (test->expected_result == SYSCALL_EPERM && err == EPERM) {
err = 0; /* error was expected, reset it */
goto out;
}
if (test->expected_result == SYSCALL_ENOTSUPP && err == ENOTSUPP) {
err = 0; /* error was expected, reset it */
goto out;
}
if (err || test->expected_result != SUCCESS)
goto err;
goto out;
err:
err = -1;
out:
/* Detaching w/o checking return code: best effort attempt. */
if (progfd != -1)
bpf_prog_detach(cgfd, test->attach_type);
close(progfd);
printf("[%s]\n", err ? "FAIL" : "PASS");
return err;
}
static int run_tests(int cgfd)
{
int passes = 0;
int fails = 0;
int i;
for (i = 0; i < ARRAY_SIZE(tests); ++i) {
if (run_test_case(cgfd, &tests[i]))
++fails;
else
++passes;
}
printf("Summary: %d PASSED, %d FAILED\n", passes, fails);
return fails ? -1 : 0;
}
int main(int argc, char **argv)
{
int cgfd = -1;
int err = 0;
if (argc < 2) {
fprintf(stderr,
"%s has to be run via %s.sh. Skip direct run.\n",
argv[0], argv[0]);
exit(err);
}
if (setup_cgroup_environment())
goto err;
cgfd = create_and_get_cgroup(CG_PATH);
if (!cgfd)
goto err;
if (join_cgroup(CG_PATH))
goto err;
if (run_tests(cgfd))
goto err;
goto out;
err:
err = -1;
out:
close(cgfd);
cleanup_cgroup_environment();
return err;
}