socket: add parse and build userdata interface

Add support for meta userdata area.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>

diff --git a/src/expression.c b/src/expression.c
index 847c88ee82c5532ad87258893cd846bea66bddeb..191bc2be104b90d8bd8bfaa5f03e457e6fd2f48d 100644 (file)
--- a/src/expression.c
+++ b/src/expression.c
@@ -1229,6 +1229,7 @@ const struct expr_ops *expr_ops_by_type(enum expr_types etype)
        case EXPR_PAYLOAD: return &payload_expr_ops;
        case EXPR_EXTHDR: return &exthdr_expr_ops;
        case EXPR_META: return &meta_expr_ops;
+       case EXPR_SOCKET: return &socket_expr_ops;
        default:
                break;
        }

diff --git a/src/socket.c b/src/socket.c
index e10b32267762c8363184657c660aee5551a0afab..d78a163a21fa3a3855f7d23f23e1234f09fa3861 100644 (file)
--- a/src/socket.c
+++ b/src/socket.c
@@ -43,6 +43,55 @@ static void socket_expr_clone(struct expr *new, const struct expr *expr)
        new->socket.key = expr->socket.key;
 }
 
+#define NFTNL_UDATA_SOCKET_KEY 0
+#define NFTNL_UDATA_SOCKET_MAX 1
+
+static int socket_expr_build_udata(struct nftnl_udata_buf *udbuf,
+                                const struct expr *expr)
+{
+       nftnl_udata_put_u32(udbuf, NFTNL_UDATA_SOCKET_KEY, expr->socket.key);
+
+       return 0;
+}
+
+static int socket_parse_udata(const struct nftnl_udata *attr, void *data)
+{
+       const struct nftnl_udata **ud = data;
+       uint8_t type = nftnl_udata_type(attr);
+       uint8_t len = nftnl_udata_len(attr);
+
+       switch (type) {
+       case NFTNL_UDATA_SOCKET_KEY:
+               if (len != sizeof(uint32_t))
+                       return -1;
+               break;
+       default:
+               return 0;
+       }
+
+       ud[type] = attr;
+       return 0;
+}
+
+static struct expr *socket_expr_parse_udata(const struct nftnl_udata *attr)
+{
+       const struct nftnl_udata *ud[NFTNL_UDATA_SOCKET_MAX + 1] = {};
+       uint32_t key;
+       int err;
+
+       err = nftnl_udata_parse(nftnl_udata_get(attr), nftnl_udata_len(attr),
+                               socket_parse_udata, ud);
+       if (err < 0)
+               return NULL;
+
+       if (!ud[NFTNL_UDATA_SOCKET_KEY])
+               return NULL;
+
+       key = nftnl_udata_get_u32(ud[NFTNL_UDATA_SOCKET_KEY]);
+
+       return socket_expr_alloc(&internal_location, key);
+}
+
 const struct expr_ops socket_expr_ops = {
        .type           = EXPR_SOCKET,
        .name           = "socket",
@@ -50,6 +99,8 @@ const struct expr_ops socket_expr_ops = {
        .json           = socket_expr_json,
        .cmp            = socket_expr_cmp,
        .clone          = socket_expr_clone,
+       .build_udata    = socket_expr_build_udata,
+       .parse_udata    = socket_expr_parse_udata,
 };
 
 struct expr *socket_expr_alloc(const struct location *loc, enum nft_socket_keys key)