expr: add last match time support

This new expression displays when last matching has happened.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/include/libnftnl/expr.h b/include/libnftnl/expr.h
index 4e6059a609dfb1ae30c1d5fb9a3211d03e7c09d9..9b90e3ea3569ce94cfb9936fdc4328644c84c941 100644 (file)
--- a/include/libnftnl/expr.h
+++ b/include/libnftnl/expr.h
@@ -311,6 +311,10 @@ enum {
        NFTNL_EXPR_SYNPROXY_FLAGS,
 };
 
+enum {
+       NFTNL_EXPR_LAST_MSECS = NFTNL_EXPR_BASE,
+};
+
 #ifdef __cplusplus
 } /* extern "C" */
 #endif

diff --git a/src/Makefile.am b/src/Makefile.am
index 90b1967420b1dd20d517161424ed766cab815e9e..c3b0ab974bd212069035cc1ae8892996c35d2949 100644 (file)
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -34,6 +34,7 @@ libnftnl_la_SOURCES = utils.c         \
                      expr/flow_offload.c \
                      expr/fib.c        \
                      expr/fwd.c        \
+                     expr/last.c       \
                      expr/limit.c      \
                      expr/log.c        \
                      expr/lookup.c     \

diff --git a/src/expr/last.c b/src/expr/last.c
new file mode 100644 (file)
index 0000000..0020fbc
--- /dev/null
+++ b/src/expr/last.c
@@ -0,0 +1,118 @@
+/*
+ * (C) 2016 by Pablo Neira Ayuso <pablo@netfilter.org>
+ *
+ * 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 <stdio.h>
+#include <stdint.h>
+#include <arpa/inet.h>
+#include <errno.h>
+#include <inttypes.h>
+
+#include <linux/netfilter/nf_tables.h>
+
+#include "internal.h"
+#include <libmnl/libmnl.h>
+#include <libnftnl/expr.h>
+#include <libnftnl/rule.h>
+
+struct nftnl_expr_last {
+       uint64_t        msecs;
+};
+
+static int nftnl_expr_last_set(struct nftnl_expr *e, uint16_t type,
+                               const void *data, uint32_t data_len)
+{
+       struct nftnl_expr_last *last = nftnl_expr_data(e);
+
+       switch (type) {
+       case NFTNL_EXPR_LAST_MSECS:
+               memcpy(&last->msecs, data, sizeof(last->msecs));
+               break;
+       default:
+               return -1;
+       }
+       return 0;
+}
+
+static const void *nftnl_expr_last_get(const struct nftnl_expr *e,
+                                       uint16_t type, uint32_t *data_len)
+{
+       struct nftnl_expr_last *last = nftnl_expr_data(e);
+
+       switch (type) {
+       case NFTNL_EXPR_LAST_MSECS:
+               *data_len = sizeof(last->msecs);
+               return &last->msecs;
+       }
+       return NULL;
+}
+
+static int nftnl_expr_last_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_LAST_MAX) < 0)
+               return MNL_CB_OK;
+
+       switch(type) {
+       case NFTA_LAST_MSECS:
+               if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0)
+                       abi_breakage();
+               break;
+       }
+
+       tb[type] = attr;
+       return MNL_CB_OK;
+}
+
+static void
+nftnl_expr_last_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
+{
+       struct nftnl_expr_last *last = nftnl_expr_data(e);
+
+       if (e->flags & (1 << NFTNL_EXPR_LAST_MSECS))
+               mnl_attr_put_u64(nlh, NFTA_LAST_MSECS, htobe64(last->msecs));
+}
+
+static int
+nftnl_expr_last_parse(struct nftnl_expr *e, struct nlattr *attr)
+{
+       struct nftnl_expr_last *last = nftnl_expr_data(e);
+       struct nlattr *tb[NFTA_LAST_MAX + 1] = {};
+
+       if (mnl_attr_parse_nested(attr, nftnl_expr_last_cb, tb) < 0)
+               return -1;
+
+       if (tb[NFTA_LAST_MSECS]) {
+               last->msecs = be64toh(mnl_attr_get_u64(tb[NFTA_LAST_MSECS]));
+               e->flags |= (1 << NFTNL_EXPR_LAST_MSECS);
+       }
+
+       return 0;
+}
+
+static int nftnl_expr_last_snprintf(char *buf, size_t len,
+                                      uint32_t flags,
+                                      const struct nftnl_expr *e)
+{
+       struct nftnl_expr_last *last = nftnl_expr_data(e);
+
+       return snprintf(buf, len, "last %"PRIu64" ", last->msecs);
+}
+
+struct expr_ops expr_ops_last = {
+       .name           = "last",
+       .alloc_len      = sizeof(struct nftnl_expr_last),
+       .max_attr       = NFTA_LAST_MAX,
+       .set            = nftnl_expr_last_set,
+       .get            = nftnl_expr_last_get,
+       .parse          = nftnl_expr_last_parse,
+       .build          = nftnl_expr_last_build,
+       .snprintf       = nftnl_expr_last_snprintf,
+};

diff --git a/src/expr_ops.c b/src/expr_ops.c
index 3538dd60a6b7a77dfe700aea86a2f3d5ffb7c9ea..7248e4f98b0a1d650fc2f99c4c56f92f60c91755 100644 (file)
--- a/src/expr_ops.c
+++ b/src/expr_ops.c
@@ -14,6 +14,7 @@ extern struct expr_ops expr_ops_dup;
 extern struct expr_ops expr_ops_exthdr;
 extern struct expr_ops expr_ops_fwd;
 extern struct expr_ops expr_ops_immediate;
+extern struct expr_ops expr_ops_last;
 extern struct expr_ops expr_ops_limit;
 extern struct expr_ops expr_ops_log;
 extern struct expr_ops expr_ops_lookup;
@@ -57,6 +58,7 @@ static struct expr_ops *expr_ops[] = {
        &expr_ops_exthdr,
        &expr_ops_fwd,
        &expr_ops_immediate,
+       &expr_ops_last,
        &expr_ops_limit,
        &expr_ops_log,
        &expr_ops_lookup,