diff options
Diffstat (limited to 'src/expr/osf.c')
| -rw-r--r-- | src/expr/osf.c | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/src/expr/osf.c b/src/expr/osf.c new file mode 100644 index 0000000..f15a722 --- /dev/null +++ b/src/expr/osf.c @@ -0,0 +1,151 @@ +#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> + +#define OSF_GENRE_SIZE 32 + +struct nftnl_expr_osf { + enum nft_registers dreg; + uint8_t ttl; + uint32_t flags; +}; + +static int nftnl_expr_osf_set(struct nftnl_expr *e, uint16_t type, + const void *data, uint32_t data_len) +{ + struct nftnl_expr_osf *osf = nftnl_expr_data(e); + + switch(type) { + case NFTNL_EXPR_OSF_DREG: + memcpy(&osf->dreg, data, sizeof(osf->dreg)); + break; + case NFTNL_EXPR_OSF_TTL: + memcpy(&osf->ttl, data, sizeof(osf->ttl)); + break; + case NFTNL_EXPR_OSF_FLAGS: + memcpy(&osf->flags, data, sizeof(osf->flags)); + break; + } + return 0; +} + +static const void * +nftnl_expr_osf_get(const struct nftnl_expr *e, uint16_t type, + uint32_t *data_len) +{ + struct nftnl_expr_osf *osf = nftnl_expr_data(e); + + switch(type) { + case NFTNL_EXPR_OSF_DREG: + *data_len = sizeof(osf->dreg); + return &osf->dreg; + case NFTNL_EXPR_OSF_TTL: + *data_len = sizeof(osf->ttl); + return &osf->ttl; + case NFTNL_EXPR_OSF_FLAGS: + *data_len = sizeof(osf->flags); + return &osf->flags; + } + return NULL; +} + +static int nftnl_expr_osf_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_OSF_MAX) < 0) + return MNL_CB_OK; + + switch(type) { + case NFTNL_EXPR_OSF_DREG: + case NFTNL_EXPR_OSF_FLAGS: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) + abi_breakage(); + break; + + case NFTNL_EXPR_OSF_TTL: + if (mnl_attr_validate(attr, MNL_TYPE_U8) < 0) + abi_breakage(); + break; + + } + + tb[type] = attr; + return MNL_CB_OK; +} + +static void +nftnl_expr_osf_build(struct nlmsghdr *nlh, const struct nftnl_expr *e) +{ + struct nftnl_expr_osf *osf = nftnl_expr_data(e); + + if (e->flags & (1 << NFTNL_EXPR_OSF_DREG)) + mnl_attr_put_u32(nlh, NFTNL_EXPR_OSF_DREG, htonl(osf->dreg)); + if (e->flags & (1 << NFTNL_EXPR_OSF_TTL)) + mnl_attr_put_u8(nlh, NFTNL_EXPR_OSF_TTL, osf->ttl); + if (e->flags & (1 << NFTNL_EXPR_OSF_FLAGS)) + if (osf->flags) + mnl_attr_put_u32(nlh, NFTNL_EXPR_OSF_FLAGS, htonl(osf->flags)); +} + +static int +nftnl_expr_osf_parse(struct nftnl_expr *e, struct nlattr *attr) +{ + struct nftnl_expr_osf *osf = nftnl_expr_data(e); + struct nlattr *tb[NFTA_OSF_MAX + 1] = {}; + + if (mnl_attr_parse_nested(attr, nftnl_expr_osf_cb, tb) < 0) + return -1; + + if (tb[NFTA_OSF_DREG]) { + osf->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_OSF_DREG])); + e->flags |= (1 << NFTNL_EXPR_OSF_DREG); + } + + if (tb[NFTA_OSF_TTL]) { + osf->ttl = mnl_attr_get_u8(tb[NFTA_OSF_TTL]); + e->flags |= (1 << NFTNL_EXPR_OSF_TTL); + } + + if (tb[NFTA_OSF_FLAGS]) { + osf->flags = ntohl(mnl_attr_get_u32(tb[NFTA_OSF_FLAGS])); + e->flags |= (1 << NFTNL_EXPR_OSF_FLAGS); + } + + return 0; +} + +static int +nftnl_expr_osf_snprintf(char *buf, size_t len, + uint32_t flags, const struct nftnl_expr *e) +{ + struct nftnl_expr_osf *osf = nftnl_expr_data(e); + int ret, offset = 0; + + if (e->flags & (1 << NFTNL_EXPR_OSF_DREG)) { + ret = snprintf(buf, len, "dreg %u ", osf->dreg); + SNPRINTF_BUFFER_SIZE(ret, len, offset); + } + + return offset; +} + +struct expr_ops expr_ops_osf = { + .name = "osf", + .alloc_len = sizeof(struct nftnl_expr_osf), + .max_attr = NFTA_OSF_MAX, + .set = nftnl_expr_osf_set, + .get = nftnl_expr_osf_get, + .parse = nftnl_expr_osf_parse, + .build = nftnl_expr_osf_build, + .output = nftnl_expr_osf_snprintf, +}; |