From 39b87dbec6c2ea78ba4ccb34e6d61ce353d792bc Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Thu, 7 Oct 2010 18:09:18 +0200 Subject: utils: add user-space expectation example This patch adds an example on how to set up a user-space expectation. Signed-off-by: Pablo Neira Ayuso --- utils/expect_create_userspace.c | 128 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 128 insertions(+) create mode 100644 utils/expect_create_userspace.c (limited to 'utils/expect_create_userspace.c') diff --git a/utils/expect_create_userspace.c b/utils/expect_create_userspace.c new file mode 100644 index 0000000..67e7b2a --- /dev/null +++ b/utils/expect_create_userspace.c @@ -0,0 +1,128 @@ +#include +#include +#include + +#include +#include + +/* + * This example shows how to setup a user-space expectation. This requires + * a Linux kernel >= 2.6.37. + */ + +int main() +{ + int ret; + struct nfct_handle *h; + struct nf_conntrack *master, *expected, *mask; + struct nf_expect *exp; + + /* + * Step 1: Setup master conntrack + */ + + master = nfct_new(); + if (!master) { + perror("nfct_new"); + exit(EXIT_FAILURE); + } + + nfct_set_attr_u8(master, ATTR_L3PROTO, AF_INET); + nfct_set_attr_u32(master, ATTR_IPV4_SRC, inet_addr("1.1.1.1")); + nfct_set_attr_u32(master, ATTR_IPV4_DST, inet_addr("2.2.2.2")); + + nfct_set_attr_u8(master, ATTR_L4PROTO, IPPROTO_TCP); + nfct_set_attr_u16(master, ATTR_PORT_SRC, htons(1025)); + nfct_set_attr_u16(master, ATTR_PORT_DST, htons(21)); + + nfct_setobjopt(master, NFCT_SOPT_SETUP_REPLY); + + nfct_set_attr_u8(master, ATTR_TCP_STATE, TCP_CONNTRACK_ESTABLISHED); + nfct_set_attr_u32(master, ATTR_TIMEOUT, 200); + + h = nfct_open(CONNTRACK, 0); + if (!h) { + perror("nfct_open"); + return -1; + } + + /* + * In a real scenario in which you want to implement an helper in + * user-space with NFQUEUE, the master conntrack does not need to + * be created, since it should already exist. + */ + ret = nfct_query(h, NFCT_Q_CREATE, master); + + printf("TEST: add master conntrack "); + if (ret == -1) + printf("(%d)(%s)\n", ret, strerror(errno)); + else + printf("(OK)\n"); + + nfct_close(h); + + expected = nfct_new(); + if (!expected) { + perror("nfct_new"); + exit(EXIT_FAILURE); + } + + nfct_set_attr_u8(expected, ATTR_L3PROTO, AF_INET); + nfct_set_attr_u32(expected, ATTR_IPV4_SRC, inet_addr("1.1.1.1")); + nfct_set_attr_u32(expected, ATTR_IPV4_DST, inet_addr("2.2.2.2")); + + nfct_set_attr_u8(expected, ATTR_L4PROTO, IPPROTO_TCP); + nfct_set_attr_u16(expected, ATTR_PORT_SRC, 0); + nfct_set_attr_u16(expected, ATTR_PORT_DST, htons(10241)); + + mask = nfct_new(); + if (!mask) { + perror("nfct_new"); + exit(EXIT_FAILURE); + } + + nfct_set_attr_u8(mask, ATTR_L3PROTO, AF_INET); + nfct_set_attr_u32(mask, ATTR_IPV4_SRC, 0xffffffff); + nfct_set_attr_u32(mask, ATTR_IPV4_DST, 0xffffffff); + + nfct_set_attr_u8(mask, ATTR_L4PROTO, IPPROTO_TCP); + nfct_set_attr_u16(mask, ATTR_PORT_SRC, 0x0000); + nfct_set_attr_u16(mask, ATTR_PORT_DST, 0xffff); + + /* + * Step 2: Setup expectation + */ + + exp = nfexp_new(); + if (!exp) { + perror("nfexp_new"); + exit(EXIT_FAILURE); + } + + nfexp_set_attr(exp, ATTR_EXP_MASTER, master); + nfexp_set_attr(exp, ATTR_EXP_EXPECTED, expected); + nfexp_set_attr(exp, ATTR_EXP_MASK, mask); + nfexp_set_attr_u32(exp, ATTR_EXP_TIMEOUT, 200); + + nfct_destroy(master); + nfct_destroy(expected); + nfct_destroy(mask); + + h = nfct_open(EXPECT, 0); + if (!h) { + perror("nfct_open"); + return -1; + } + + ret = nfexp_query(h, NFCT_Q_CREATE, exp); + + printf("TEST: create expectation "); + if (ret == -1) + printf("(%d)(%s)\n", ret, strerror(errno)); + else + printf("(OK)\n"); + + nfct_close(h); + + ret == -1 ? exit(EXIT_FAILURE) : exit(EXIT_SUCCESS); +} -- cgit v1.2.3