Add support for ct expectation objects, used to define specific expectations.

Signed-off-by: Stéphane Veyret <svey...@gmail.com>
---
 include/libnftnl/object.h           |   7 +
 include/linux/netfilter/nf_tables.h |  13 +-
 include/obj.h                       |   7 +
 src/Makefile.am                     |   1 +
 src/obj/ct_expect.c                 | 193 ++++++++++++++++++++++++++++
 src/object.c                        |   1 +
 6 files changed, 221 insertions(+), 1 deletion(-)
 create mode 100644 src/obj/ct_expect.c

diff --git a/include/libnftnl/object.h b/include/libnftnl/object.h
index 4ce2230..dcb631c 100644
--- a/include/libnftnl/object.h
+++ b/include/libnftnl/object.h
@@ -70,6 +70,13 @@ enum {
        NFTNL_OBJ_CT_TIMEOUT_ARRAY,
 };
 
+enum {
+       NFTNL_OBJ_CT_EXPECT_L3PROTO = NFTNL_OBJ_BASE,
+       NFTNL_OBJ_CT_EXPECT_L4PROTO,
+       NFTNL_OBJ_CT_EXPECT_DPORT,
+       NFTNL_OBJ_CT_EXPECT_TIMEOUT,
+};
+
 enum {
        NFTNL_OBJ_LIMIT_RATE    = NFTNL_OBJ_BASE,
        NFTNL_OBJ_LIMIT_UNIT,
diff --git a/include/linux/netfilter/nf_tables.h 
b/include/linux/netfilter/nf_tables.h
index fd38cdc..59969f1 100644
--- a/include/linux/netfilter/nf_tables.h
+++ b/include/linux/netfilter/nf_tables.h
@@ -1429,6 +1429,16 @@ enum nft_ct_timeout_attributes {
 };
 #define NFTA_CT_TIMEOUT_MAX    (__NFTA_CT_TIMEOUT_MAX - 1)
 
+enum nft_ct_expectation_attributes {
+       NFTA_CT_EXPECT_UNSPEC,
+       NFTA_CT_EXPECT_L3PROTO,
+       NFTA_CT_EXPECT_L4PROTO,
+       NFTA_CT_EXPECT_DPORT,
+       NFTA_CT_EXPECT_TIMEOUT,
+       __NFTA_CT_EXPECT_MAX,
+};
+#define NFTA_CT_EXPECT_MAX     (__NFTA_CT_EXPECT_MAX - 1)
+
 #define NFT_OBJECT_UNSPEC      0
 #define NFT_OBJECT_COUNTER     1
 #define NFT_OBJECT_QUOTA       2
@@ -1438,7 +1448,8 @@ enum nft_ct_timeout_attributes {
 #define NFT_OBJECT_TUNNEL      6
 #define NFT_OBJECT_CT_TIMEOUT  7
 #define NFT_OBJECT_SECMARK     8
-#define __NFT_OBJECT_MAX       9
+#define NFT_OBJECT_CT_EXPECT   9
+#define __NFT_OBJECT_MAX       10
 #define NFT_OBJECT_MAX         (__NFT_OBJECT_MAX - 1)
 
 /**
diff --git a/include/obj.h b/include/obj.h
index 35b5c40..f5935ab 100644
--- a/include/obj.h
+++ b/include/obj.h
@@ -42,6 +42,12 @@ struct nftnl_obj {
                        uint8_t         l4proto;
                        uint32_t        timeout[NFTNL_CTTIMEOUT_ARRAY_MAX];
                } ct_timeout;
+               struct nftnl_obj_ct_expect {
+                       uint16_t        l3proto;
+                       uint8_t         l4proto;
+                       uint16_t        dport;
+                       uint32_t        timeout;
+               } ct_expect;
                struct nftnl_obj_limit {
                        uint64_t        rate;
                        uint64_t        unit;
@@ -99,6 +105,7 @@ extern struct obj_ops obj_ops_counter;
 extern struct obj_ops obj_ops_quota;
 extern struct obj_ops obj_ops_ct_helper;
 extern struct obj_ops obj_ops_ct_timeout;
+extern struct obj_ops obj_ops_ct_expect;
 extern struct obj_ops obj_ops_limit;
 extern struct obj_ops obj_ops_tunnel;
 extern struct obj_ops obj_ops_secmark;
diff --git a/src/Makefile.am b/src/Makefile.am
index 2d5873f..8f9c022 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -65,4 +65,5 @@ libnftnl_la_SOURCES = utils.c         \
                      obj/limit.c       \
                      obj/ct_timeout.c  \
                      obj/secmark.c     \
+                     obj/ct_expect.c   \
                      libnftnl.map
diff --git a/src/obj/ct_expect.c b/src/obj/ct_expect.c
new file mode 100644
index 0000000..16066c4
--- /dev/null
+++ b/src/obj/ct_expect.c
@@ -0,0 +1,193 @@
+/*
+ * (C) 2019 by Stéphane Veyret <svey...@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <arpa/inet.h>
+#include <errno.h>
+
+#include <libmnl/libmnl.h>
+
+#include "obj.h"
+
+static int nftnl_obj_ct_expect_set(struct nftnl_obj *e, uint16_t type,
+                                  const void *data, uint32_t data_len)
+{
+       struct nftnl_obj_ct_expect *exp = nftnl_obj_data(e);
+
+       switch (type) {
+       case NFTNL_OBJ_CT_EXPECT_L3PROTO:
+               memcpy(&exp->l3proto, data, sizeof(exp->l3proto));
+               break;
+       case NFTNL_OBJ_CT_EXPECT_L4PROTO:
+               memcpy(&exp->l4proto, data, sizeof(exp->l4proto));
+               break;
+       case NFTNL_OBJ_CT_EXPECT_DPORT:
+               memcpy(&exp->dport, data, sizeof(exp->dport));
+               break;
+       case NFTNL_OBJ_CT_EXPECT_TIMEOUT:
+               memcpy(&exp->timeout, data, sizeof(exp->timeout));
+               break;
+       default:
+               return -1;
+       }
+       return 0;
+}
+
+static const void *nftnl_obj_ct_expect_get(const struct nftnl_obj *e,
+                                          uint16_t type, uint32_t *data_len)
+{
+       struct nftnl_obj_ct_expect *exp = nftnl_obj_data(e);
+
+       switch (type) {
+       case NFTNL_OBJ_CT_EXPECT_L3PROTO:
+               *data_len = sizeof(exp->l3proto);
+               return &exp->l3proto;
+       case NFTNL_OBJ_CT_EXPECT_L4PROTO:
+               *data_len = sizeof(exp->l4proto);
+               return &exp->l4proto;
+       case NFTNL_OBJ_CT_EXPECT_DPORT:
+               *data_len = sizeof(exp->dport);
+               return &exp->dport;
+       case NFTNL_OBJ_CT_EXPECT_TIMEOUT:
+               *data_len = sizeof(exp->timeout);
+               return &exp->timeout;
+       }
+       return NULL;
+}
+
+static int nftnl_obj_ct_expect_cb(const struct nlattr *attr, void *data)
+{
+       int type = mnl_attr_get_type(attr);
+       const struct nlattr **tb = data;
+
+       if (mnl_attr_type_valid(attr, NFTA_CT_EXPECT_MAX) < 0)
+               return MNL_CB_OK;
+
+       switch (type) {
+       case NFTA_CT_EXPECT_L3PROTO:
+               if (mnl_attr_validate(attr, MNL_TYPE_U16) < 0)
+                       abi_breakage();
+               break;
+       case NFTA_CT_EXPECT_L4PROTO:
+               if (mnl_attr_validate(attr, MNL_TYPE_U8) < 0)
+                       abi_breakage();
+               break;
+       case NFTA_CT_EXPECT_DPORT:
+               if (mnl_attr_validate(attr, MNL_TYPE_U16) < 0)
+                       abi_breakage();
+               break;
+       case NFTA_CT_EXPECT_TIMEOUT:
+               if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
+                       abi_breakage();
+               break;
+       }
+
+       tb[type] = attr;
+       return MNL_CB_OK;
+}
+
+static void
+nftnl_obj_ct_expect_build(struct nlmsghdr *nlh, const struct nftnl_obj *e)
+{
+       struct nftnl_obj_ct_expect *exp = nftnl_obj_data(e);
+
+       if (e->flags & (1 << NFTNL_OBJ_CT_EXPECT_L3PROTO))
+               mnl_attr_put_u16(nlh, NFTA_CT_EXPECT_L3PROTO, 
htons(exp->l3proto));
+       if (e->flags & (1 << NFTNL_OBJ_CT_EXPECT_L4PROTO))
+               mnl_attr_put_u8(nlh, NFTA_CT_EXPECT_L4PROTO, exp->l4proto);
+       if (e->flags & (1 << NFTNL_OBJ_CT_EXPECT_DPORT))
+               mnl_attr_put_u16(nlh, NFTA_CT_EXPECT_DPORT, htons(exp->dport));
+       if (e->flags & (1 << NFTNL_OBJ_CT_EXPECT_TIMEOUT))
+               mnl_attr_put_u32(nlh, NFTA_CT_EXPECT_TIMEOUT, exp->timeout);
+}
+
+static int
+nftnl_obj_ct_expect_parse(struct nftnl_obj *e, struct nlattr *attr)
+{
+       struct nftnl_obj_ct_expect *exp = nftnl_obj_data(e);
+       struct nlattr *tb[NFTA_CT_EXPECT_MAX + 1] = {};
+
+       if (mnl_attr_parse_nested(attr, nftnl_obj_ct_expect_cb, tb) < 0)
+               return -1;
+
+       if (tb[NFTA_CT_EXPECT_L3PROTO]) {
+               exp->l3proto = 
ntohs(mnl_attr_get_u16(tb[NFTA_CT_EXPECT_L3PROTO]));
+               e->flags |= (1 << NFTNL_OBJ_CT_EXPECT_L3PROTO);
+       }
+       if (tb[NFTA_CT_EXPECT_L4PROTO]) {
+               exp->l4proto = mnl_attr_get_u8(tb[NFTA_CT_EXPECT_L4PROTO]);
+               e->flags |= (1 << NFTNL_OBJ_CT_EXPECT_L4PROTO);
+       }
+       if (tb[NFTA_CT_EXPECT_DPORT]) {
+               exp->dport = ntohs(mnl_attr_get_u16(tb[NFTA_CT_EXPECT_DPORT]));
+               e->flags |= (1 << NFTNL_OBJ_CT_EXPECT_DPORT);
+       }
+       if (tb[NFTA_CT_EXPECT_TIMEOUT]) {
+               exp->timeout = mnl_attr_get_u32(tb[NFTA_CT_EXPECT_TIMEOUT]);
+               e->flags |= (1 << NFTNL_OBJ_CT_EXPECT_TIMEOUT);
+       }
+
+       return 0;
+}
+
+static int nftnl_obj_ct_expect_snprintf_default(char *buf, size_t len,
+                                              const struct nftnl_obj *e)
+{
+       int ret = 0;
+       int offset = 0, remain = len;
+       struct nftnl_obj_ct_expect *exp = nftnl_obj_data(e);
+
+       if (e->flags & (1 << NFTNL_OBJ_CT_EXPECT_L3PROTO)) {
+               ret = snprintf(buf + offset, len, "family %d ", exp->l3proto);
+               SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+       }
+       if (e->flags & (1 << NFTNL_OBJ_CT_EXPECT_L4PROTO)) {
+               ret = snprintf(buf + offset, len, "protocol %d ", exp->l4proto);
+               SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+       }
+       if (e->flags & (1 << NFTNL_OBJ_CT_EXPECT_DPORT)) {
+               ret = snprintf(buf + offset, len, "dport %d ", exp->dport);
+               SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+       }
+       if (e->flags & (1 << NFTNL_OBJ_CT_EXPECT_TIMEOUT)) {
+               ret = snprintf(buf + offset, len, "timeout %d ", exp->timeout);
+               SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+       }
+
+       buf[offset] = '\0';
+       return offset;
+}
+
+static int nftnl_obj_ct_expect_snprintf(char *buf, size_t len, uint32_t type,
+                                      uint32_t flags,
+                                      const struct nftnl_obj *e)
+{
+       if (len)
+               buf[0] = '\0';
+
+       switch (type) {
+       case NFTNL_OUTPUT_DEFAULT:
+               return nftnl_obj_ct_expect_snprintf_default(buf, len, e);
+       case NFTNL_OUTPUT_JSON:
+       default:
+               break;
+       }
+       return -1;
+}
+
+struct obj_ops obj_ops_ct_expect = {
+       .name           = "ct_expect",
+       .type           = NFT_OBJECT_CT_EXPECT,
+       .alloc_len      = sizeof(struct nftnl_obj_ct_expect),
+       .max_attr       = NFTA_CT_EXPECT_MAX,
+       .set            = nftnl_obj_ct_expect_set,
+       .get            = nftnl_obj_ct_expect_get,
+       .parse          = nftnl_obj_ct_expect_parse,
+       .build          = nftnl_obj_ct_expect_build,
+       .snprintf       = nftnl_obj_ct_expect_snprintf,
+};
diff --git a/src/object.c b/src/object.c
index 5c8d183..23f8840 100644
--- a/src/object.c
+++ b/src/object.c
@@ -33,6 +33,7 @@ static struct obj_ops *obj_ops[__NFT_OBJECT_MAX] = {
        [NFT_OBJECT_TUNNEL]     = &obj_ops_tunnel,
        [NFT_OBJECT_CT_TIMEOUT] = &obj_ops_ct_timeout,
        [NFT_OBJECT_SECMARK]    = &obj_ops_secmark,
+       [NFT_OBJECT_CT_EXPECT] = &obj_ops_ct_expect,
 };
 
 static struct obj_ops *nftnl_obj_ops_lookup(uint32_t type)
-- 
2.21.0

Reply via email to