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Diffstat (limited to '')
| -rw-r--r-- | src/rt.c | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/src/rt.c b/src/rt.c new file mode 100644 index 0000000..f5c8055 --- /dev/null +++ b/src/rt.c @@ -0,0 +1,211 @@ +/* + * Routing expression related definition and types. + * + * 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 version 2 as + * published by the Free Software Foundation. + */ + +#include <nft.h> + +#include <errno.h> +#include <stddef.h> +#include <stdio.h> +#include <arpa/inet.h> +#include <linux/netfilter.h> + +#include <nftables.h> +#include <expression.h> +#include <datatype.h> +#include <rt.h> +#include <rule.h> +#include <json.h> + +void realm_table_rt_init(struct nft_ctx *ctx) +{ + ctx->output.tbl.realm = rt_symbol_table_init("/etc/iproute2/rt_realms"); +} + +void realm_table_rt_exit(struct nft_ctx *ctx) +{ + rt_symbol_table_free(ctx->output.tbl.realm); +} + +static void realm_type_print(const struct expr *expr, struct output_ctx *octx) +{ + return symbolic_constant_print(octx->tbl.realm, expr, true, octx); +} + +static struct error_record *realm_type_parse(struct parse_ctx *ctx, + const struct expr *sym, + struct expr **res) +{ + return symbolic_constant_parse(ctx, sym, ctx->tbl->realm, res); +} + +const struct datatype realm_type = { + .type = TYPE_REALM, + .name = "realm", + .desc = "routing realm", + .byteorder = BYTEORDER_HOST_ENDIAN, + .size = 4 * BITS_PER_BYTE, + .basetype = &integer_type, + .print = realm_type_print, + .parse = realm_type_parse, + .flags = DTYPE_F_PREFIX, +}; + +const struct rt_template rt_templates[] = { + [NFT_RT_CLASSID] = RT_TEMPLATE("classid", + &realm_type, + 4 * BITS_PER_BYTE, + BYTEORDER_HOST_ENDIAN, + false), + [NFT_RT_NEXTHOP4] = RT_TEMPLATE("nexthop", + &ipaddr_type, + 4 * BITS_PER_BYTE, + BYTEORDER_BIG_ENDIAN, + true), + [NFT_RT_NEXTHOP6] = RT_TEMPLATE("nexthop", + &ip6addr_type, + 16 * BITS_PER_BYTE, + BYTEORDER_BIG_ENDIAN, + true), + [NFT_RT_TCPMSS] = RT_TEMPLATE("mtu", + &integer_type, + 2 * BITS_PER_BYTE, + BYTEORDER_HOST_ENDIAN, + false), + [NFT_RT_XFRM] = RT_TEMPLATE("ipsec", + &boolean_type, + BITS_PER_BYTE, + BYTEORDER_HOST_ENDIAN, + false), +}; + +static void rt_expr_print(const struct expr *expr, struct output_ctx *octx) +{ + const char *ip = ""; + + switch (expr->rt.key) { + case NFT_RT_NEXTHOP4: + ip = "ip "; + break; + case NFT_RT_NEXTHOP6: + ip = "ip6 "; + break; + default: + break; + } + + nft_print(octx, "rt %s%s", ip, rt_templates[expr->rt.key].token); +} + +static bool rt_expr_cmp(const struct expr *e1, const struct expr *e2) +{ + return e1->rt.key == e2->rt.key; +} + +static void rt_expr_clone(struct expr *new, const struct expr *expr) +{ + new->rt.key = expr->rt.key; +} + +#define NFTNL_UDATA_RT_KEY 0 +#define NFTNL_UDATA_RT_MAX 1 + +static int rt_expr_build_udata(struct nftnl_udata_buf *udbuf, + const struct expr *expr) +{ + nftnl_udata_put_u32(udbuf, NFTNL_UDATA_RT_KEY, expr->rt.key); + + return 0; +} + +static int rt_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_RT_KEY: + if (len != sizeof(uint32_t)) + return -1; + break; + default: + return 0; + } + + ud[type] = attr; + return 0; +} + +static struct expr *rt_expr_parse_udata(const struct nftnl_udata *attr) +{ + const struct nftnl_udata *ud[NFTNL_UDATA_RT_MAX + 1] = {}; + uint32_t key; + int err; + + err = nftnl_udata_parse(nftnl_udata_get(attr), nftnl_udata_len(attr), + rt_parse_udata, ud); + if (err < 0) + return NULL; + + if (!ud[NFTNL_UDATA_RT_KEY]) + return NULL; + + key = nftnl_udata_get_u32(ud[NFTNL_UDATA_RT_KEY]); + + return rt_expr_alloc(&internal_location, key, false); +} + +const struct expr_ops rt_expr_ops = { + .type = EXPR_RT, + .name = "rt", + .print = rt_expr_print, + .json = rt_expr_json, + .cmp = rt_expr_cmp, + .clone = rt_expr_clone, + .parse_udata = rt_expr_parse_udata, + .build_udata = rt_expr_build_udata, +}; + +struct expr *rt_expr_alloc(const struct location *loc, enum nft_rt_keys key, + bool invalid) +{ + const struct rt_template *tmpl = &rt_templates[key]; + struct expr *expr; + + if (invalid && tmpl->invalid) + expr = expr_alloc(loc, EXPR_RT, &invalid_type, + tmpl->byteorder, 0); + else + expr = expr_alloc(loc, EXPR_RT, tmpl->dtype, + tmpl->byteorder, tmpl->len); + expr->rt.key = key; + + return expr; +} + +void rt_expr_update_type(struct proto_ctx *ctx, struct expr *expr) +{ + const struct proto_desc *desc; + + switch (expr->rt.key) { + case NFT_RT_NEXTHOP4: + desc = ctx->protocol[PROTO_BASE_NETWORK_HDR].desc; + if (desc == &proto_ip) + datatype_set(expr, &ipaddr_type); + else if (desc == &proto_ip6) { + expr->rt.key++; + datatype_set(expr, &ip6addr_type); + } + expr->len = expr->dtype->size; + break; + default: + break; + } +} |