static int build_rule_snat(int index, const char *address,
struct nftnl_rule **res)
{
struct nftnl_rule *rule;
struct nftnl_expr *expr;
uint32_t snat;
int err;
/*
* # nft --debug netlink add rule connman nat-postrouting \
* oif eth0 snat 1.2.3.4
* ip connman nat-postrouting
* [ meta load oif => reg 1 ]
* [ cmp eq reg 1 0x0000000b ]
* [ immediate reg 1 0x04030201 ]
* [ nat snat ip addr_min reg 1 addr_max reg 0 ]
*/
rule = nftnl_rule_alloc();
if (!rule)
return -ENOMEM;
nftnl_rule_set(rule, NFTNL_RULE_TABLE, CONNMAN_TABLE);
nftnl_rule_set(rule, NFTNL_RULE_CHAIN, CONNMAN_CHAIN_NAT_POST);
/* OIF */
expr = nftnl_expr_alloc("meta");
if (!expr)
goto err;
nftnl_expr_set_u32(expr, NFTNL_EXPR_META_KEY, NFT_META_OIF);
nftnl_expr_set_u32(expr, NFTNL_EXPR_META_DREG, NFT_REG_1);
nftnl_rule_add_expr(rule, expr);
err = add_cmp(rule, NFT_REG_1, NFT_CMP_EQ, &index, sizeof(index));
if (err < 0)
goto err;
/* snat */
expr = nftnl_expr_alloc("immediate");
if (!expr)
goto err;
snat = inet_addr(address);
nftnl_expr_set_u32(expr, NFTNL_EXPR_IMM_DREG, NFT_REG_1);
nftnl_expr_set(expr, NFTNL_EXPR_IMM_DATA, &snat, sizeof(snat));
nftnl_rule_add_expr(rule, expr);
expr = nftnl_expr_alloc("nat");
if (!expr)
goto err;
nftnl_expr_set_u32(expr, NFTNL_EXPR_NAT_TYPE, NFT_NAT_SNAT);
nftnl_expr_set_u32(expr, NFTNL_EXPR_NAT_FAMILY, NFPROTO_IPV4);
nftnl_expr_set_u32(expr, NFTNL_EXPR_NAT_REG_ADDR_MIN, NFT_REG_1);
nftnl_rule_add_expr(rule, expr);
*res = rule;
return 0;
err:
nftnl_rule_free(rule);
return -ENOMEM;
}
static int build_rule_src_ip(const char *src_ip, uint32_t mark, struct nftnl_rule **res)
{
struct nftnl_rule *rule;
struct nftnl_expr *expr;
int err;
in_addr_t s_addr;
/*
* # nft --debug netlink add rule connman route-output \
* ip saddr 192.168.10.31 mark set 1234
*
* ip connman route-output
* [ payload load 4b @ network header + 12 => reg 1 ]
* [ cmp eq reg 1 0x1f0aa8c0 ]
* [ immediate reg 1 0x000004d2 ]
* [ meta set mark with reg 1 ]
*/
rule = nftnl_rule_alloc();
if (!rule)
return -ENOMEM;
nftnl_rule_set(rule, NFTNL_RULE_TABLE, CONNMAN_TABLE);
nftnl_rule_set(rule, NFTNL_RULE_CHAIN, CONNMAN_CHAIN_ROUTE_OUTPUT);
/* family ipv4 */
nftnl_rule_set_u32(rule, NFTNL_RULE_FAMILY, NFPROTO_IPV4);
/* source IP */
err = add_payload(rule, NFT_PAYLOAD_NETWORK_HEADER, NFT_REG_1,
offsetof(struct iphdr, saddr), sizeof(struct in_addr));
if (err < 0)
goto err;
s_addr = inet_addr(src_ip);
err = add_cmp(rule, NFT_REG_1, NFT_CMP_EQ, &s_addr, sizeof(s_addr));
if (err < 0)
goto err;
expr = nftnl_expr_alloc("immediate");
if (!expr)
goto err;
nftnl_expr_set_u32(expr, NFTNL_EXPR_IMM_DREG, NFT_REG_1);
nftnl_expr_set(expr, NFTNL_EXPR_IMM_DATA, &mark, sizeof(mark));
nftnl_rule_add_expr(rule, expr);
expr = nftnl_expr_alloc("meta");
if (!expr)
goto err;
nftnl_expr_set_u32(expr, NFTNL_EXPR_META_KEY, NFT_META_MARK);
nftnl_expr_set_u32(expr, NFTNL_EXPR_META_SREG, NFT_REG_1);
nftnl_rule_add_expr(rule, expr);
*res = rule;
return 0;
err:
return -ENOMEM;
}
static int build_rule_marking(uid_t uid, uint32_t mark, struct nftnl_rule **res)
{
struct nftnl_rule *rule;
struct nftnl_expr *expr;
int err;
/*
* http://wiki.nftables.org/wiki-nftables/index.php/Setting_packet_metainformation
* http://wiki.nftables.org/wiki-nftables/index.php/Matching_packet_metainformation
*
* # nft --debug netlink add rule connman route-output \
* meta skuid wagi mark set 1234
*
* ip connman route-output
* [ meta load skuid => reg 1 ]
* [ cmp eq reg 1 0x000003e8 ]
* [ immediate reg 1 0x000004d2 ]
* [ meta set mark with reg 1 ]
*/
rule = nftnl_rule_alloc();
if (!rule)
return -ENOMEM;
nftnl_rule_set(rule, NFTNL_RULE_TABLE, CONNMAN_TABLE);
nftnl_rule_set(rule, NFTNL_RULE_CHAIN, CONNMAN_CHAIN_ROUTE_OUTPUT);
expr = nftnl_expr_alloc("meta");
if (!expr)
goto err;
nftnl_expr_set_u32(expr, NFTNL_EXPR_META_KEY, NFT_META_SKUID);
nftnl_expr_set_u32(expr, NFTNL_EXPR_META_DREG, NFT_REG_1);
nftnl_rule_add_expr(rule, expr);
err = add_cmp(rule, NFT_REG_1, NFT_CMP_EQ, &uid, sizeof(uid));
if (err < 0)
goto err;
expr = nftnl_expr_alloc("immediate");
if (!expr)
goto err;
nftnl_expr_set_u32(expr, NFTNL_EXPR_IMM_DREG, NFT_REG_1);
nftnl_expr_set(expr, NFTNL_EXPR_IMM_DATA, &mark, sizeof(mark));
nftnl_rule_add_expr(rule, expr);
expr = nftnl_expr_alloc("meta");
if (!expr)
goto err;
nftnl_expr_set_u32(expr, NFTNL_EXPR_META_KEY, NFT_META_MARK);
nftnl_expr_set_u32(expr, NFTNL_EXPR_META_SREG, NFT_REG_1);
nftnl_rule_add_expr(rule, expr);
*res = rule;
return 0;
err:
return -ENOMEM;
}
int main(int argc, char *argv[])
{
struct nftnl_rule *a, *b;
struct nftnl_expr *ex;
struct nlmsghdr *nlh;
char buf[4096];
struct nftnl_expr_iter *iter_a, *iter_b;
struct nftnl_expr *rule_a, *rule_b;
uint32_t chain_t = 0x12345678;
uint32_t data_t = 0x12345678;
a = nftnl_rule_alloc();
b = nftnl_rule_alloc();
if (a == NULL || b == NULL)
print_err("OOM");
ex = nftnl_expr_alloc("immediate");
if (ex == NULL)
print_err("OOM");
nftnl_expr_set_u32(ex, NFTNL_EXPR_IMM_DREG, 0x1234568);
nftnl_expr_set(ex, NFTNL_EXPR_IMM_DATA, &chain_t, sizeof(chain_t));
nftnl_expr_set_u32(ex, NFTNL_EXPR_IMM_VERDICT, 0x12345678);
nftnl_expr_set(ex, NFTNL_EXPR_IMM_CHAIN, &data_t, sizeof(data_t));
nftnl_rule_add_expr(a, ex);
nlh = nftnl_rule_nlmsg_build_hdr(buf, NFT_MSG_NEWRULE, AF_INET, 0, 1234);
nftnl_rule_nlmsg_build_payload(nlh, a);
if (nftnl_rule_nlmsg_parse(nlh, b) < 0)
print_err("parsing problems");
iter_a = nftnl_expr_iter_create(a);
iter_b = nftnl_expr_iter_create(b);
if (iter_a == NULL || iter_b == NULL)
print_err("OOM");
rule_a = nftnl_expr_iter_next(iter_a);
rule_b = nftnl_expr_iter_next(iter_b);
if (rule_a == NULL || rule_b == NULL)
print_err("OOM");
cmp_nftnl_expr(rule_a, rule_b);
if (nftnl_expr_iter_next(iter_a) != NULL ||
nftnl_expr_iter_next(iter_b) != NULL)
print_err("More 1 expr.");
nftnl_expr_iter_destroy(iter_a);
nftnl_expr_iter_destroy(iter_b);
nftnl_rule_free(a);
nftnl_rule_free(b);
if (!test_ok)
exit(EXIT_FAILURE);
printf("%s: \033[32mOK\e[0m\n", argv[0]);
return EXIT_SUCCESS;
}
int main(int argc, char *argv[])
{
struct nftnl_rule *a, *b;
struct nftnl_expr *ex;
struct nlmsghdr *nlh;
char buf[4096];
struct nftnl_expr_iter *iter_a, *iter_b;
struct nftnl_expr *rule_a, *rule_b;
a = nftnl_rule_alloc();
b = nftnl_rule_alloc();
if (a == NULL || b == NULL)
print_err("OOM");
ex = nftnl_expr_alloc("byteorder");
if (ex == NULL)
print_err("OOM");
nftnl_expr_set_u32(ex, NFTNL_EXPR_BYTEORDER_SREG, 0x12345678);
nftnl_expr_set_u32(ex, NFTNL_EXPR_BYTEORDER_DREG, 0x12345678);
nftnl_expr_set_u32(ex, NFTNL_EXPR_BYTEORDER_OP, 0x12345678);
nftnl_expr_set_u32(ex, NFTNL_EXPR_BYTEORDER_LEN, 0x12345678);
nftnl_expr_set_u32(ex, NFTNL_EXPR_BYTEORDER_SIZE, 0x12345678);
nftnl_rule_add_expr(a, ex);
nlh = nftnl_rule_nlmsg_build_hdr(buf, NFT_MSG_NEWRULE, AF_INET, 0, 1234);
nftnl_rule_nlmsg_build_payload(nlh, a);
if (nftnl_rule_nlmsg_parse(nlh, b) < 0)
print_err("parsing problems");
iter_a = nftnl_expr_iter_create(a);
iter_b = nftnl_expr_iter_create(b);
if (iter_a == NULL || iter_b == NULL)
print_err("OOM");
rule_a = nftnl_expr_iter_next(iter_a);
rule_b = nftnl_expr_iter_next(iter_b);
if (rule_a == NULL || rule_b == NULL)
print_err("OOM");
cmp_nftnl_expr(rule_a,rule_b);
if (nftnl_expr_iter_next(iter_a) != NULL ||
nftnl_expr_iter_next(iter_b) != NULL)
print_err("More 1 expr.");
nftnl_expr_iter_destroy(iter_a);
nftnl_expr_iter_destroy(iter_b);
nftnl_rule_free(a);
nftnl_rule_free(b);
if (!test_ok)
exit(EXIT_FAILURE);
printf("%s: \033[32mOK\e[0m\n", argv[0]);
return EXIT_SUCCESS;
}
static void add_counter(struct nftnl_rule *r)
{
struct nftnl_expr *e;
e = nftnl_expr_alloc("counter");
if (e == NULL) {
perror("expr counter oom");
exit(EXIT_FAILURE);
}
nftnl_rule_add_expr(r, e);
}
void add_meta(struct nftnl_rule *r, uint32_t key)
{
struct nftnl_expr *expr;
expr = nftnl_expr_alloc("meta");
if (expr == NULL)
return;
nftnl_expr_set_u32(expr, NFTNL_EXPR_META_KEY, key);
nftnl_expr_set_u32(expr, NFTNL_EXPR_META_DREG, NFT_REG_1);
nftnl_rule_add_expr(r, expr);
}
void add_cmp_ptr(struct nftnl_rule *r, uint32_t op, void *data, size_t len)
{
struct nftnl_expr *expr;
expr = nftnl_expr_alloc("cmp");
if (expr == NULL)
return;
nftnl_expr_set_u32(expr, NFTNL_EXPR_CMP_SREG, NFT_REG_1);
nftnl_expr_set_u32(expr, NFTNL_EXPR_CMP_OP, op);
nftnl_expr_set(expr, NFTNL_EXPR_CMP_DATA, data, len);
nftnl_rule_add_expr(r, expr);
}
void add_payload(struct nftnl_rule *r, int offset, int len, uint32_t base)
{
struct nftnl_expr *expr;
expr = nftnl_expr_alloc("payload");
if (expr == NULL)
return;
nftnl_expr_set_u32(expr, NFTNL_EXPR_PAYLOAD_BASE, base);
nftnl_expr_set_u32(expr, NFTNL_EXPR_PAYLOAD_DREG, NFT_REG_1);
nftnl_expr_set_u32(expr, NFTNL_EXPR_PAYLOAD_OFFSET, offset);
nftnl_expr_set_u32(expr, NFTNL_EXPR_PAYLOAD_LEN, len);
nftnl_rule_add_expr(r, expr);
}
/* bitwise operation is = sreg & mask ^ xor */
void add_bitwise_u16(struct nftnl_rule *r, int mask, int xor)
{
struct nftnl_expr *expr;
expr = nftnl_expr_alloc("bitwise");
if (expr == NULL)
return;
nftnl_expr_set_u32(expr, NFTNL_EXPR_BITWISE_SREG, NFT_REG_1);
nftnl_expr_set_u32(expr, NFTNL_EXPR_BITWISE_DREG, NFT_REG_1);
nftnl_expr_set_u32(expr, NFTNL_EXPR_BITWISE_LEN, sizeof(uint16_t));
nftnl_expr_set(expr, NFTNL_EXPR_BITWISE_MASK, &mask, sizeof(uint16_t));
nftnl_expr_set(expr, NFTNL_EXPR_BITWISE_XOR, &xor, sizeof(uint16_t));
nftnl_rule_add_expr(r, expr);
}
static int add_cmp(struct nftnl_rule *rule, uint32_t sreg, uint32_t op,
const void *data, uint32_t data_len)
{
struct nftnl_expr *expr;
expr = nftnl_expr_alloc("cmp");
if (!expr)
return -ENOMEM;
nftnl_expr_set_u32(expr, NFTNL_EXPR_CMP_SREG, sreg);
nftnl_expr_set_u32(expr, NFTNL_EXPR_CMP_OP, op);
nftnl_expr_set(expr, NFTNL_EXPR_CMP_DATA, data, data_len);
nftnl_rule_add_expr(rule, expr);
return 0;
}
static void add_cmp(struct nftnl_rule *r, uint32_t sreg, uint32_t op,
const void *data, uint32_t data_len)
{
struct nftnl_expr *e;
e = nftnl_expr_alloc("cmp");
if (e == NULL) {
perror("expr cmp oom");
exit(EXIT_FAILURE);
}
nftnl_expr_set_u32(e, NFTNL_EXPR_CMP_SREG, sreg);
nftnl_expr_set_u32(e, NFTNL_EXPR_CMP_OP, op);
nftnl_expr_set(e, NFTNL_EXPR_CMP_DATA, data, data_len);
nftnl_rule_add_expr(r, e);
}
static void add_bitwise(struct nftnl_rule *r, uint8_t *mask, size_t len)
{
struct nftnl_expr *expr;
uint32_t xor[4] = { 0 };
expr = nftnl_expr_alloc("bitwise");
if (expr == NULL)
return;
nftnl_expr_set_u32(expr, NFTNL_EXPR_BITWISE_SREG, NFT_REG_1);
nftnl_expr_set_u32(expr, NFTNL_EXPR_BITWISE_DREG, NFT_REG_1);
nftnl_expr_set_u32(expr, NFTNL_EXPR_BITWISE_LEN, len);
nftnl_expr_set(expr, NFTNL_EXPR_BITWISE_MASK, mask, len);
nftnl_expr_set(expr, NFTNL_EXPR_BITWISE_XOR, &xor, len);
nftnl_rule_add_expr(r, expr);
}
static int add_payload(struct nftnl_rule *rule, uint32_t base,
uint32_t dreg, uint32_t offset, uint32_t len)
{
struct nftnl_expr *expr;
expr = nftnl_expr_alloc("payload");
if (!expr)
return -ENOMEM;
nftnl_expr_set_u32(expr, NFTNL_EXPR_PAYLOAD_BASE, base);
nftnl_expr_set_u32(expr, NFTNL_EXPR_PAYLOAD_DREG, dreg);
nftnl_expr_set_u32(expr, NFTNL_EXPR_PAYLOAD_OFFSET, offset);
nftnl_expr_set_u32(expr, NFTNL_EXPR_PAYLOAD_LEN, len);
nftnl_rule_add_expr(rule, expr);
return 0;
}
static void add_payload(struct nftnl_rule *r, uint32_t base, uint32_t dreg,
uint32_t offset, uint32_t len)
{
struct nftnl_expr *e;
e = nftnl_expr_alloc("payload");
if (e == NULL) {
perror("expr payload oom");
exit(EXIT_FAILURE);
}
nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_BASE, base);
nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_DREG, dreg);
nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_OFFSET, offset);
nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_LEN, len);
nftnl_rule_add_expr(r, e);
}
static int add_bitwise(struct nftnl_rule *rule, int reg, const void *mask,
size_t len)
{
struct nftnl_expr *expr;
uint8_t *xor;
expr = nftnl_expr_alloc("bitwise");
if (!expr)
return -ENOMEM;
xor = alloca(len);
memset(xor, 0, len);
nftnl_expr_set_u32(expr, NFTNL_EXPR_BITWISE_SREG, reg);
nftnl_expr_set_u32(expr, NFTNL_EXPR_BITWISE_DREG, reg);
nftnl_expr_set_u32(expr, NFTNL_EXPR_BITWISE_LEN, len);
nftnl_expr_set(expr, NFTNL_EXPR_BITWISE_MASK, mask, len);
nftnl_expr_set(expr, NFTNL_EXPR_BITWISE_XOR, xor, len);
nftnl_rule_add_expr(rule, expr);
return 0;
}
static int build_rule_nat(const char *address, unsigned char prefixlen,
const char *interface, struct nftnl_rule **res)
{
struct nftnl_rule *rule;
struct in_addr ipv4_addr, ipv4_mask;
struct nftnl_expr *expr;
int err;
/*
* # nft --debug netlink add rule connman nat-postrouting \
* oifname eth0 ip saddr 10.10.0.0/24 masquerade
*
* ip connman nat-postrouting
* [ meta load oifname => reg 1 ]
* [ cmp eq reg 1 0x30687465 0x00000000 0x00000000 0x00000000 ]
* [ payload load 4b @ network header + 12 => reg 1 ]
* [ bitwise reg 1 = (reg=1 & 0x00ffffff ) ^ 0x00000000 ]
* [ cmp eq reg 1 0x00000a0a ]
* [ masq ]
*/
rule = nftnl_rule_alloc();
if (!rule)
return -ENOMEM;
nftnl_rule_set(rule, NFTNL_RULE_TABLE, CONNMAN_TABLE);
nftnl_rule_set(rule, NFTNL_RULE_CHAIN, CONNMAN_CHAIN_NAT_POST);
/* family ipv4 */
nftnl_rule_set_u32(rule, NFTNL_RULE_FAMILY, NFPROTO_IPV4);
/* oifname */
expr = nftnl_expr_alloc("meta");
if (!expr)
goto err;
nftnl_expr_set_u32(expr, NFTNL_EXPR_META_KEY, NFT_META_OIFNAME);
nftnl_expr_set_u32(expr, NFTNL_EXPR_META_DREG, NFT_REG_1);
nftnl_rule_add_expr(rule, expr);
err = add_cmp(rule, NFT_REG_1, NFT_CMP_EQ, interface,
strlen(interface) + 1);
if (err < 0)
goto err;
/* source */
ipv4_mask.s_addr = htonl((0xffffffff << (32 - prefixlen)) & 0xffffffff);
ipv4_addr.s_addr = inet_addr(address);
ipv4_addr.s_addr &= ipv4_mask.s_addr;
err = add_payload(rule, NFT_PAYLOAD_NETWORK_HEADER, NFT_REG_1,
offsetof(struct iphdr, saddr), sizeof(struct in_addr));
if (err < 0)
goto err;
err = add_bitwise(rule, NFT_REG_1, &ipv4_mask.s_addr,
sizeof(struct in_addr));
if (err < 0)
goto err;
err = add_cmp(rule, NFT_REG_1, NFT_CMP_EQ, &ipv4_addr.s_addr,
sizeof(struct in_addr));
if (err < 0)
goto err;
/* masquerade */
expr = nftnl_expr_alloc("masq");
if (!expr)
goto err;
nftnl_rule_add_expr(rule, expr);
*res = rule;
return 0;
err:
nftnl_rule_free(rule);
return -ENOMEM;
}
