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Diffstat (limited to '')
| -rw-r--r-- | src/expr/rt.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/src/expr/rt.c b/src/expr/rt.c new file mode 100644 index 0000000..695a658 --- /dev/null +++ b/src/expr/rt.c @@ -0,0 +1,166 @@ +/* + * Copyright (c) 2016 Anders K. Pedersen <akp@cohaesio.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 <stdio.h> +#include <stdint.h> +#include <string.h> +#include <arpa/inet.h> +#include <errno.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_rt { + enum nft_rt_keys key; + enum nft_registers dreg; +}; + +static int +nftnl_expr_rt_set(struct nftnl_expr *e, uint16_t type, + const void *data, uint32_t data_len) +{ + struct nftnl_expr_rt *rt = nftnl_expr_data(e); + + switch (type) { + case NFTNL_EXPR_RT_KEY: + memcpy(&rt->key, data, sizeof(rt->key)); + break; + case NFTNL_EXPR_RT_DREG: + memcpy(&rt->dreg, data, sizeof(rt->dreg)); + break; + default: + return -1; + } + return 0; +} + +static const void * +nftnl_expr_rt_get(const struct nftnl_expr *e, uint16_t type, + uint32_t *data_len) +{ + struct nftnl_expr_rt *rt = nftnl_expr_data(e); + + switch (type) { + case NFTNL_EXPR_RT_KEY: + *data_len = sizeof(rt->key); + return &rt->key; + case NFTNL_EXPR_RT_DREG: + *data_len = sizeof(rt->dreg); + return &rt->dreg; + } + return NULL; +} + +static int nftnl_expr_rt_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_RT_MAX) < 0) + return MNL_CB_OK; + + switch (type) { + case NFTA_RT_KEY: + case NFTA_RT_DREG: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) + abi_breakage(); + break; + } + + tb[type] = attr; + return MNL_CB_OK; +} + +static void +nftnl_expr_rt_build(struct nlmsghdr *nlh, const struct nftnl_expr *e) +{ + struct nftnl_expr_rt *rt = nftnl_expr_data(e); + + if (e->flags & (1 << NFTNL_EXPR_RT_KEY)) + mnl_attr_put_u32(nlh, NFTA_RT_KEY, htonl(rt->key)); + if (e->flags & (1 << NFTNL_EXPR_RT_DREG)) + mnl_attr_put_u32(nlh, NFTA_RT_DREG, htonl(rt->dreg)); +} + +static int +nftnl_expr_rt_parse(struct nftnl_expr *e, struct nlattr *attr) +{ + struct nftnl_expr_rt *rt = nftnl_expr_data(e); + struct nlattr *tb[NFTA_RT_MAX+1] = {}; + + if (mnl_attr_parse_nested(attr, nftnl_expr_rt_cb, tb) < 0) + return -1; + + if (tb[NFTA_RT_KEY]) { + rt->key = ntohl(mnl_attr_get_u32(tb[NFTA_RT_KEY])); + e->flags |= (1 << NFTNL_EXPR_RT_KEY); + } + if (tb[NFTA_RT_DREG]) { + rt->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_RT_DREG])); + e->flags |= (1 << NFTNL_EXPR_RT_DREG); + } + + return 0; +} + +static const char *rt_key2str_array[NFT_RT_MAX + 1] = { + [NFT_RT_CLASSID] = "classid", + [NFT_RT_NEXTHOP4] = "nexthop4", + [NFT_RT_NEXTHOP6] = "nexthop6", + [NFT_RT_TCPMSS] = "tcpmss", + [NFT_RT_XFRM] = "ipsec", +}; + +static const char *rt_key2str(uint8_t key) +{ + if (key <= NFT_RT_MAX) + return rt_key2str_array[key]; + + return "unknown"; +} + +static inline int str2rt_key(const char *str) +{ + int i; + + for (i = 0; i < NFT_RT_MAX; i++) { + if (strcmp(str, rt_key2str_array[i]) == 0) + return i; + } + + errno = EINVAL; + return -1; +} + +static int +nftnl_expr_rt_snprintf(char *buf, size_t len, + uint32_t flags, const struct nftnl_expr *e) +{ + struct nftnl_expr_rt *rt = nftnl_expr_data(e); + + if (e->flags & (1 << NFTNL_EXPR_RT_DREG)) { + return snprintf(buf, len, "load %s => reg %u ", + rt_key2str(rt->key), rt->dreg); + } + return 0; +} + +struct expr_ops expr_ops_rt = { + .name = "rt", + .alloc_len = sizeof(struct nftnl_expr_rt), + .max_attr = NFTA_RT_MAX, + .set = nftnl_expr_rt_set, + .get = nftnl_expr_rt_get, + .parse = nftnl_expr_rt_parse, + .build = nftnl_expr_rt_build, + .output = nftnl_expr_rt_snprintf, +}; |