From 824d199e49f1b35502bfe0b99083df2066b907d0 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Tue, 17 Dec 2019 18:16:58 +0100 Subject: numgen: add parse and build userdata interface Add support for meta userdata area. Signed-off-by: Pablo Neira Ayuso Signed-off-by: Florian Westphal --- src/expression.c | 1 + src/numgen.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 63 insertions(+) diff --git a/src/expression.c b/src/expression.c index 14bf329e..1791454e 100644 --- a/src/expression.c +++ b/src/expression.c @@ -1232,6 +1232,7 @@ const struct expr_ops *expr_ops_by_type(enum expr_types etype) case EXPR_SOCKET: return &socket_expr_ops; case EXPR_OSF: return &osf_expr_ops; case EXPR_CT: return &ct_expr_ops; + case EXPR_NUMGEN: return &numgen_expr_ops; default: break; } diff --git a/src/numgen.c b/src/numgen.c index 8318d0a2..ea2b2626 100644 --- a/src/numgen.c +++ b/src/numgen.c @@ -51,6 +51,66 @@ static void numgen_expr_clone(struct expr *new, const struct expr *expr) new->numgen.offset = expr->numgen.offset; } +#define NFTNL_UDATA_NUMGEN_TYPE 0 +#define NFTNL_UDATA_NUMGEN_MOD 1 +#define NFTNL_UDATA_NUMGEN_OFFSET 2 +#define NFTNL_UDATA_NUMGEN_MAX 3 + +static int numgen_expr_build_udata(struct nftnl_udata_buf *udbuf, + const struct expr *expr) +{ + nftnl_udata_put_u32(udbuf, NFTNL_UDATA_NUMGEN_TYPE, expr->numgen.type); + nftnl_udata_put_u32(udbuf, NFTNL_UDATA_NUMGEN_MOD, expr->numgen.mod); + nftnl_udata_put_u32(udbuf, NFTNL_UDATA_NUMGEN_OFFSET, expr->numgen.offset); + + return 0; +} + +static int numgen_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_NUMGEN_TYPE: + case NFTNL_UDATA_NUMGEN_MOD: + case NFTNL_UDATA_NUMGEN_OFFSET: + if (len != sizeof(uint32_t)) + return -1; + break; + default: + return 0; + } + + ud[type] = attr; + return 0; +} + +static struct expr *numgen_expr_parse_udata(const struct nftnl_udata *attr) +{ + const struct nftnl_udata *ud[NFTNL_UDATA_NUMGEN_MAX + 1] = {}; + enum nft_ng_types type; + uint32_t mod, offset; + int err; + + err = nftnl_udata_parse(nftnl_udata_get(attr), nftnl_udata_len(attr), + numgen_parse_udata, ud); + if (err < 0) + return NULL; + + if (!ud[NFTNL_UDATA_NUMGEN_TYPE] || + !ud[NFTNL_UDATA_NUMGEN_MOD] || + !ud[NFTNL_UDATA_NUMGEN_OFFSET]) + return NULL; + + type = nftnl_udata_get_u32(ud[NFTNL_UDATA_NUMGEN_TYPE]); + mod = nftnl_udata_get_u32(ud[NFTNL_UDATA_NUMGEN_MOD]); + offset = nftnl_udata_get_u32(ud[NFTNL_UDATA_NUMGEN_OFFSET]); + + return numgen_expr_alloc(&internal_location, type, mod, offset); +} + const struct expr_ops numgen_expr_ops = { .type = EXPR_NUMGEN, .name = "numgen", @@ -58,6 +118,8 @@ const struct expr_ops numgen_expr_ops = { .json = numgen_expr_json, .cmp = numgen_expr_cmp, .clone = numgen_expr_clone, + .parse_udata = numgen_expr_parse_udata, + .build_udata = numgen_expr_build_udata, }; struct expr *numgen_expr_alloc(const struct location *loc, -- cgit v1.2.3