diff options
Diffstat (limited to 'src/expr/fib.c')
-rw-r--r-- | src/expr/fib.c | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/src/expr/fib.c b/src/expr/fib.c new file mode 100644 index 0000000..957f929 --- /dev/null +++ b/src/expr/fib.c @@ -0,0 +1,202 @@ +/* + * (C) 2016 Red Hat GmbH + * Author: Florian Westphal <fw@strlen.de> + * + * 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 <inttypes.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_fib { + uint32_t flags; + uint32_t result; + enum nft_registers dreg; +}; + +static int +nftnl_expr_fib_set(struct nftnl_expr *e, uint16_t result, + const void *data, uint32_t data_len) +{ + struct nftnl_expr_fib *fib = nftnl_expr_data(e); + + switch (result) { + case NFTNL_EXPR_FIB_RESULT: + memcpy(&fib->result, data, sizeof(fib->result)); + break; + case NFTNL_EXPR_FIB_DREG: + memcpy(&fib->dreg, data, sizeof(fib->dreg)); + break; + case NFTNL_EXPR_FIB_FLAGS: + memcpy(&fib->flags, data, sizeof(fib->flags)); + break; + default: + return -1; + } + return 0; +} + +static const void * +nftnl_expr_fib_get(const struct nftnl_expr *e, uint16_t result, + uint32_t *data_len) +{ + struct nftnl_expr_fib *fib = nftnl_expr_data(e); + + switch (result) { + case NFTNL_EXPR_FIB_RESULT: + *data_len = sizeof(fib->result); + return &fib->result; + case NFTNL_EXPR_FIB_DREG: + *data_len = sizeof(fib->dreg); + return &fib->dreg; + case NFTNL_EXPR_FIB_FLAGS: + *data_len = sizeof(fib->flags); + return &fib->flags; + } + return NULL; +} + +static int nftnl_expr_fib_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_FIB_MAX) < 0) + return MNL_CB_OK; + + switch (type) { + case NFTA_FIB_RESULT: + case NFTA_FIB_DREG: + case NFTA_FIB_FLAGS: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) + abi_breakage(); + break; + } + + tb[type] = attr; + return MNL_CB_OK; +} + +static void +nftnl_expr_fib_build(struct nlmsghdr *nlh, const struct nftnl_expr *e) +{ + struct nftnl_expr_fib *fib = nftnl_expr_data(e); + + if (e->flags & (1 << NFTNL_EXPR_FIB_FLAGS)) + mnl_attr_put_u32(nlh, NFTA_FIB_FLAGS, htonl(fib->flags)); + if (e->flags & (1 << NFTNL_EXPR_FIB_RESULT)) + mnl_attr_put_u32(nlh, NFTA_FIB_RESULT, htonl(fib->result)); + if (e->flags & (1 << NFTNL_EXPR_FIB_DREG)) + mnl_attr_put_u32(nlh, NFTA_FIB_DREG, htonl(fib->dreg)); +} + +static int +nftnl_expr_fib_parse(struct nftnl_expr *e, struct nlattr *attr) +{ + struct nftnl_expr_fib *fib = nftnl_expr_data(e); + struct nlattr *tb[NFTA_FIB_MAX+1] = {}; + int ret = 0; + + if (mnl_attr_parse_nested(attr, nftnl_expr_fib_cb, tb) < 0) + return -1; + + if (tb[NFTA_FIB_RESULT]) { + fib->result = ntohl(mnl_attr_get_u32(tb[NFTA_FIB_RESULT])); + e->flags |= (1 << NFTNL_EXPR_FIB_RESULT); + } + if (tb[NFTA_FIB_DREG]) { + fib->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_FIB_DREG])); + e->flags |= (1 << NFTNL_EXPR_FIB_DREG); + } + if (tb[NFTA_FIB_FLAGS]) { + fib->flags = ntohl(mnl_attr_get_u32(tb[NFTA_FIB_FLAGS])); + e->flags |= (1 << NFTNL_EXPR_FIB_FLAGS); + } + return ret; +} + +static const char *fib_type[NFT_FIB_RESULT_MAX + 1] = { + [NFT_FIB_RESULT_OIF] = "oif", + [NFT_FIB_RESULT_OIFNAME] = "oifname", + [NFT_FIB_RESULT_ADDRTYPE] = "type", +}; + +static const char *fib_type_str(enum nft_fib_result r) +{ + if (r <= NFT_FIB_RESULT_MAX) + return fib_type[r]; + + return "unknown"; +} + +static int +nftnl_expr_fib_snprintf(char *buf, size_t remain, + uint32_t printflags, const struct nftnl_expr *e) +{ + struct nftnl_expr_fib *fib = nftnl_expr_data(e); + uint32_t flags = fib->flags & ~NFTA_FIB_F_PRESENT; + uint32_t present_flag = fib->flags & NFTA_FIB_F_PRESENT; + int offset = 0, ret, i; + static const struct { + int bit; + const char *name; + } tab[] = { + { NFTA_FIB_F_SADDR, "saddr" }, + { NFTA_FIB_F_DADDR, "daddr" }, + { NFTA_FIB_F_MARK, "mark" }, + { NFTA_FIB_F_IIF, "iif" }, + { NFTA_FIB_F_OIF, "oif" }, + }; + + for (i = 0; i < (sizeof(tab) / sizeof(tab[0])); i++) { + if (flags & tab[i].bit) { + ret = snprintf(buf + offset, remain, "%s ", + tab[i].name); + SNPRINTF_BUFFER_SIZE(ret, remain, offset); + + flags &= ~tab[i].bit; + if (flags) { + ret = snprintf(buf + offset, remain, ". "); + SNPRINTF_BUFFER_SIZE(ret, remain, offset); + } + } + } + + if (flags) { + ret = snprintf(buf + offset, remain, "unknown 0x%" PRIx32, + flags); + SNPRINTF_BUFFER_SIZE(ret, remain, offset); + } + + ret = snprintf(buf + offset, remain, "%s%s => reg %d ", + fib_type_str(fib->result), + present_flag ? " present" : "", + fib->dreg); + SNPRINTF_BUFFER_SIZE(ret, remain, offset); + + return offset; +} + +struct expr_ops expr_ops_fib = { + .name = "fib", + .alloc_len = sizeof(struct nftnl_expr_fib), + .max_attr = NFTA_FIB_MAX, + .set = nftnl_expr_fib_set, + .get = nftnl_expr_fib_get, + .parse = nftnl_expr_fib_parse, + .build = nftnl_expr_fib_build, + .output = nftnl_expr_fib_snprintf, +}; |