From 42468fb6df61ac7cdb325cc3be32375bdfce6b4b Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 6 Aug 2018 13:35:05 +0200 Subject: expr: add support for matching tunnel metadata Signed-off-by: Pablo Neira Ayuso --- src/expr/tunnel.c | 192 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 192 insertions(+) create mode 100644 src/expr/tunnel.c (limited to 'src/expr/tunnel.c') diff --git a/src/expr/tunnel.c b/src/expr/tunnel.c new file mode 100644 index 0000000..2067c35 --- /dev/null +++ b/src/expr/tunnel.c @@ -0,0 +1,192 @@ +/* + * (C) 2018 by Pablo Neira Ayuso + * + * 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 +#include +#include +#include +#include +#include + +#include "internal.h" +#include +#include +#include + +struct nftnl_expr_tunnel { + enum nft_tunnel_keys key; + enum nft_registers dreg; +}; + +static int nftnl_expr_tunnel_set(struct nftnl_expr *e, uint16_t type, + const void *data, uint32_t data_len) +{ + struct nftnl_expr_tunnel *tunnel = nftnl_expr_data(e); + + switch(type) { + case NFTNL_EXPR_TUNNEL_KEY: + tunnel->key = *((uint32_t *)data); + break; + case NFTNL_EXPR_TUNNEL_DREG: + tunnel->dreg = *((uint32_t *)data); + break; + default: + return -1; + } + return 0; +} + +static const void * +nftnl_expr_tunnel_get(const struct nftnl_expr *e, uint16_t type, + uint32_t *data_len) +{ + struct nftnl_expr_tunnel *tunnel = nftnl_expr_data(e); + + switch(type) { + case NFTNL_EXPR_TUNNEL_KEY: + *data_len = sizeof(tunnel->key); + return &tunnel->key; + case NFTNL_EXPR_TUNNEL_DREG: + *data_len = sizeof(tunnel->dreg); + return &tunnel->dreg; + } + return NULL; +} + +static int nftnl_expr_tunnel_cb(const struct nlattr *attr, void *data) +{ + const struct nlattr **tb = data; + int type = mnl_attr_get_type(attr); + + if (mnl_attr_type_valid(attr, NFTA_TUNNEL_MAX) < 0) + return MNL_CB_OK; + + switch(type) { + case NFTA_TUNNEL_KEY: + case NFTA_TUNNEL_DREG: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) + abi_breakage(); + break; + } + + tb[type] = attr; + return MNL_CB_OK; +} + +static void +nftnl_expr_tunnel_build(struct nlmsghdr *nlh, const struct nftnl_expr *e) +{ + struct nftnl_expr_tunnel *tunnel = nftnl_expr_data(e); + + if (e->flags & (1 << NFTNL_EXPR_TUNNEL_KEY)) + mnl_attr_put_u32(nlh, NFTA_TUNNEL_KEY, htonl(tunnel->key)); + if (e->flags & (1 << NFTNL_EXPR_TUNNEL_DREG)) + mnl_attr_put_u32(nlh, NFTA_TUNNEL_DREG, htonl(tunnel->dreg)); +} + +static int +nftnl_expr_tunnel_parse(struct nftnl_expr *e, struct nlattr *attr) +{ + struct nftnl_expr_tunnel *tunnel = nftnl_expr_data(e); + struct nlattr *tb[NFTA_TUNNEL_MAX + 1] = {}; + + if (mnl_attr_parse_nested(attr, nftnl_expr_tunnel_cb, tb) < 0) + return -1; + + if (tb[NFTA_TUNNEL_KEY]) { + tunnel->key = ntohl(mnl_attr_get_u32(tb[NFTA_TUNNEL_KEY])); + e->flags |= (1 << NFTNL_EXPR_TUNNEL_KEY); + } + if (tb[NFTA_TUNNEL_DREG]) { + tunnel->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_TUNNEL_DREG])); + e->flags |= (1 << NFTNL_EXPR_TUNNEL_DREG); + } + + return 0; +} + +static const char *tunnel_key2str_array[NFT_TUNNEL_MAX + 1] = { + [NFT_TUNNEL_PATH] = "path", + [NFT_TUNNEL_ID] = "id", +}; + +static const char *tunnel_key2str(uint8_t key) +{ + if (key <= NFT_TUNNEL_MAX) + return tunnel_key2str_array[key]; + + return "unknown"; +} + +static inline int str2tunnel_key(const char *str) +{ + int i; + + for (i = 0; i <= NFT_TUNNEL_MAX; i++) { + if (strcmp(str, tunnel_key2str_array[i]) == 0) + return i; + } + + errno = EINVAL; + return -1; +} + +static int +nftnl_expr_tunnel_snprintf_default(char *buf, size_t len, + const struct nftnl_expr *e) +{ + struct nftnl_expr_tunnel *tunnel = nftnl_expr_data(e); + + if (e->flags & (1 << NFTNL_EXPR_TUNNEL_DREG)) { + return snprintf(buf, len, "load %s => reg %u ", + tunnel_key2str(tunnel->key), tunnel->dreg); + } + return 0; +} + +static int nftnl_expr_tunnel_export(char *buf, size_t size, + const struct nftnl_expr *e, int type) +{ + struct nftnl_expr_tunnel *tunnel = nftnl_expr_data(e); + NFTNL_BUF_INIT(b, buf, size); + + if (e->flags & (1 << NFTNL_EXPR_TUNNEL_DREG)) + nftnl_buf_u32(&b, type, tunnel->dreg, DREG); + if (e->flags & (1 << NFTNL_EXPR_TUNNEL_KEY)) + nftnl_buf_str(&b, type, tunnel_key2str(tunnel->key), KEY); + + return nftnl_buf_done(&b); +} + +static int +nftnl_expr_tunnel_snprintf(char *buf, size_t len, uint32_t type, + uint32_t flags, const struct nftnl_expr *e) +{ + switch (type) { + case NFTNL_OUTPUT_DEFAULT: + return nftnl_expr_tunnel_snprintf_default(buf, len, e); + case NFTNL_OUTPUT_XML: + case NFTNL_OUTPUT_JSON: + return nftnl_expr_tunnel_export(buf, len, e, type); + default: + break; + } + return -1; +} + +struct expr_ops expr_ops_tunnel = { + .name = "tunnel", + .alloc_len = sizeof(struct nftnl_expr_tunnel), + .max_attr = NFTA_TUNNEL_MAX, + .set = nftnl_expr_tunnel_set, + .get = nftnl_expr_tunnel_get, + .parse = nftnl_expr_tunnel_parse, + .build = nftnl_expr_tunnel_build, + .snprintf = nftnl_expr_tunnel_snprintf, +}; -- cgit v1.2.3