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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /net/netfilter/nft_bitwise.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/netfilter/nft_bitwise.c')
-rw-r--r-- | net/netfilter/nft_bitwise.c | 533 |
1 files changed, 533 insertions, 0 deletions
diff --git a/net/netfilter/nft_bitwise.c b/net/netfilter/nft_bitwise.c new file mode 100644 index 000000000..b84312df9 --- /dev/null +++ b/net/netfilter/nft_bitwise.c @@ -0,0 +1,533 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net> + * + * Development of this code funded by Astaro AG (http://www.astaro.com/) + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/netlink.h> +#include <linux/netfilter.h> +#include <linux/netfilter/nf_tables.h> +#include <net/netfilter/nf_tables_core.h> +#include <net/netfilter/nf_tables.h> +#include <net/netfilter/nf_tables_offload.h> + +struct nft_bitwise { + u8 sreg; + u8 dreg; + enum nft_bitwise_ops op:8; + u8 len; + struct nft_data mask; + struct nft_data xor; + struct nft_data data; +}; + +static void nft_bitwise_eval_bool(u32 *dst, const u32 *src, + const struct nft_bitwise *priv) +{ + unsigned int i; + + for (i = 0; i < DIV_ROUND_UP(priv->len, sizeof(u32)); i++) + dst[i] = (src[i] & priv->mask.data[i]) ^ priv->xor.data[i]; +} + +static void nft_bitwise_eval_lshift(u32 *dst, const u32 *src, + const struct nft_bitwise *priv) +{ + u32 shift = priv->data.data[0]; + unsigned int i; + u32 carry = 0; + + for (i = DIV_ROUND_UP(priv->len, sizeof(u32)); i > 0; i--) { + dst[i - 1] = (src[i - 1] << shift) | carry; + carry = src[i - 1] >> (BITS_PER_TYPE(u32) - shift); + } +} + +static void nft_bitwise_eval_rshift(u32 *dst, const u32 *src, + const struct nft_bitwise *priv) +{ + u32 shift = priv->data.data[0]; + unsigned int i; + u32 carry = 0; + + for (i = 0; i < DIV_ROUND_UP(priv->len, sizeof(u32)); i++) { + dst[i] = carry | (src[i] >> shift); + carry = src[i] << (BITS_PER_TYPE(u32) - shift); + } +} + +void nft_bitwise_eval(const struct nft_expr *expr, + struct nft_regs *regs, const struct nft_pktinfo *pkt) +{ + const struct nft_bitwise *priv = nft_expr_priv(expr); + const u32 *src = ®s->data[priv->sreg]; + u32 *dst = ®s->data[priv->dreg]; + + switch (priv->op) { + case NFT_BITWISE_BOOL: + nft_bitwise_eval_bool(dst, src, priv); + break; + case NFT_BITWISE_LSHIFT: + nft_bitwise_eval_lshift(dst, src, priv); + break; + case NFT_BITWISE_RSHIFT: + nft_bitwise_eval_rshift(dst, src, priv); + break; + } +} + +static const struct nla_policy nft_bitwise_policy[NFTA_BITWISE_MAX + 1] = { + [NFTA_BITWISE_SREG] = { .type = NLA_U32 }, + [NFTA_BITWISE_DREG] = { .type = NLA_U32 }, + [NFTA_BITWISE_LEN] = { .type = NLA_U32 }, + [NFTA_BITWISE_MASK] = { .type = NLA_NESTED }, + [NFTA_BITWISE_XOR] = { .type = NLA_NESTED }, + [NFTA_BITWISE_OP] = { .type = NLA_U32 }, + [NFTA_BITWISE_DATA] = { .type = NLA_NESTED }, +}; + +static int nft_bitwise_init_bool(struct nft_bitwise *priv, + const struct nlattr *const tb[]) +{ + struct nft_data_desc mask = { + .type = NFT_DATA_VALUE, + .size = sizeof(priv->mask), + .len = priv->len, + }; + struct nft_data_desc xor = { + .type = NFT_DATA_VALUE, + .size = sizeof(priv->xor), + .len = priv->len, + }; + int err; + + if (tb[NFTA_BITWISE_DATA]) + return -EINVAL; + + if (!tb[NFTA_BITWISE_MASK] || + !tb[NFTA_BITWISE_XOR]) + return -EINVAL; + + err = nft_data_init(NULL, &priv->mask, &mask, tb[NFTA_BITWISE_MASK]); + if (err < 0) + return err; + + err = nft_data_init(NULL, &priv->xor, &xor, tb[NFTA_BITWISE_XOR]); + if (err < 0) + goto err_xor_err; + + return 0; + +err_xor_err: + nft_data_release(&priv->mask, mask.type); + + return err; +} + +static int nft_bitwise_init_shift(struct nft_bitwise *priv, + const struct nlattr *const tb[]) +{ + struct nft_data_desc desc = { + .type = NFT_DATA_VALUE, + .size = sizeof(priv->data), + .len = sizeof(u32), + }; + int err; + + if (tb[NFTA_BITWISE_MASK] || + tb[NFTA_BITWISE_XOR]) + return -EINVAL; + + if (!tb[NFTA_BITWISE_DATA]) + return -EINVAL; + + err = nft_data_init(NULL, &priv->data, &desc, tb[NFTA_BITWISE_DATA]); + if (err < 0) + return err; + + if (priv->data.data[0] >= BITS_PER_TYPE(u32)) { + nft_data_release(&priv->data, desc.type); + return -EINVAL; + } + + return 0; +} + +static int nft_bitwise_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_bitwise *priv = nft_expr_priv(expr); + u32 len; + int err; + + err = nft_parse_u32_check(tb[NFTA_BITWISE_LEN], U8_MAX, &len); + if (err < 0) + return err; + + priv->len = len; + + err = nft_parse_register_load(tb[NFTA_BITWISE_SREG], &priv->sreg, + priv->len); + if (err < 0) + return err; + + err = nft_parse_register_store(ctx, tb[NFTA_BITWISE_DREG], + &priv->dreg, NULL, NFT_DATA_VALUE, + priv->len); + if (err < 0) + return err; + + if (tb[NFTA_BITWISE_OP]) { + priv->op = ntohl(nla_get_be32(tb[NFTA_BITWISE_OP])); + switch (priv->op) { + case NFT_BITWISE_BOOL: + case NFT_BITWISE_LSHIFT: + case NFT_BITWISE_RSHIFT: + break; + default: + return -EOPNOTSUPP; + } + } else { + priv->op = NFT_BITWISE_BOOL; + } + + switch(priv->op) { + case NFT_BITWISE_BOOL: + err = nft_bitwise_init_bool(priv, tb); + break; + case NFT_BITWISE_LSHIFT: + case NFT_BITWISE_RSHIFT: + err = nft_bitwise_init_shift(priv, tb); + break; + } + + return err; +} + +static int nft_bitwise_dump_bool(struct sk_buff *skb, + const struct nft_bitwise *priv) +{ + if (nft_data_dump(skb, NFTA_BITWISE_MASK, &priv->mask, + NFT_DATA_VALUE, priv->len) < 0) + return -1; + + if (nft_data_dump(skb, NFTA_BITWISE_XOR, &priv->xor, + NFT_DATA_VALUE, priv->len) < 0) + return -1; + + return 0; +} + +static int nft_bitwise_dump_shift(struct sk_buff *skb, + const struct nft_bitwise *priv) +{ + if (nft_data_dump(skb, NFTA_BITWISE_DATA, &priv->data, + NFT_DATA_VALUE, sizeof(u32)) < 0) + return -1; + return 0; +} + +static int nft_bitwise_dump(struct sk_buff *skb, const struct nft_expr *expr) +{ + const struct nft_bitwise *priv = nft_expr_priv(expr); + int err = 0; + + if (nft_dump_register(skb, NFTA_BITWISE_SREG, priv->sreg)) + return -1; + if (nft_dump_register(skb, NFTA_BITWISE_DREG, priv->dreg)) + return -1; + if (nla_put_be32(skb, NFTA_BITWISE_LEN, htonl(priv->len))) + return -1; + if (nla_put_be32(skb, NFTA_BITWISE_OP, htonl(priv->op))) + return -1; + + switch (priv->op) { + case NFT_BITWISE_BOOL: + err = nft_bitwise_dump_bool(skb, priv); + break; + case NFT_BITWISE_LSHIFT: + case NFT_BITWISE_RSHIFT: + err = nft_bitwise_dump_shift(skb, priv); + break; + } + + return err; +} + +static struct nft_data zero; + +static int nft_bitwise_offload(struct nft_offload_ctx *ctx, + struct nft_flow_rule *flow, + const struct nft_expr *expr) +{ + const struct nft_bitwise *priv = nft_expr_priv(expr); + struct nft_offload_reg *reg = &ctx->regs[priv->dreg]; + + if (priv->op != NFT_BITWISE_BOOL) + return -EOPNOTSUPP; + + if (memcmp(&priv->xor, &zero, sizeof(priv->xor)) || + priv->sreg != priv->dreg || priv->len != reg->len) + return -EOPNOTSUPP; + + memcpy(®->mask, &priv->mask, sizeof(priv->mask)); + + return 0; +} + +static bool nft_bitwise_reduce(struct nft_regs_track *track, + const struct nft_expr *expr) +{ + const struct nft_bitwise *priv = nft_expr_priv(expr); + const struct nft_bitwise *bitwise; + unsigned int regcount; + u8 dreg; + int i; + + if (!track->regs[priv->sreg].selector) + return false; + + bitwise = nft_expr_priv(track->regs[priv->dreg].selector); + if (track->regs[priv->sreg].selector == track->regs[priv->dreg].selector && + track->regs[priv->sreg].num_reg == 0 && + track->regs[priv->dreg].bitwise && + track->regs[priv->dreg].bitwise->ops == expr->ops && + priv->sreg == bitwise->sreg && + priv->dreg == bitwise->dreg && + priv->op == bitwise->op && + priv->len == bitwise->len && + !memcmp(&priv->mask, &bitwise->mask, sizeof(priv->mask)) && + !memcmp(&priv->xor, &bitwise->xor, sizeof(priv->xor)) && + !memcmp(&priv->data, &bitwise->data, sizeof(priv->data))) { + track->cur = expr; + return true; + } + + if (track->regs[priv->sreg].bitwise || + track->regs[priv->sreg].num_reg != 0) { + nft_reg_track_cancel(track, priv->dreg, priv->len); + return false; + } + + if (priv->sreg != priv->dreg) { + nft_reg_track_update(track, track->regs[priv->sreg].selector, + priv->dreg, priv->len); + } + + dreg = priv->dreg; + regcount = DIV_ROUND_UP(priv->len, NFT_REG32_SIZE); + for (i = 0; i < regcount; i++, dreg++) + track->regs[dreg].bitwise = expr; + + return false; +} + +static const struct nft_expr_ops nft_bitwise_ops = { + .type = &nft_bitwise_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_bitwise)), + .eval = nft_bitwise_eval, + .init = nft_bitwise_init, + .dump = nft_bitwise_dump, + .reduce = nft_bitwise_reduce, + .offload = nft_bitwise_offload, +}; + +static int +nft_bitwise_extract_u32_data(const struct nlattr * const tb, u32 *out) +{ + struct nft_data data; + struct nft_data_desc desc = { + .type = NFT_DATA_VALUE, + .size = sizeof(data), + .len = sizeof(u32), + }; + int err; + + err = nft_data_init(NULL, &data, &desc, tb); + if (err < 0) + return err; + + *out = data.data[0]; + + return 0; +} + +static int nft_bitwise_fast_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_bitwise_fast_expr *priv = nft_expr_priv(expr); + int err; + + err = nft_parse_register_load(tb[NFTA_BITWISE_SREG], &priv->sreg, + sizeof(u32)); + if (err < 0) + return err; + + err = nft_parse_register_store(ctx, tb[NFTA_BITWISE_DREG], &priv->dreg, + NULL, NFT_DATA_VALUE, sizeof(u32)); + if (err < 0) + return err; + + if (tb[NFTA_BITWISE_DATA]) + return -EINVAL; + + if (!tb[NFTA_BITWISE_MASK] || + !tb[NFTA_BITWISE_XOR]) + return -EINVAL; + + err = nft_bitwise_extract_u32_data(tb[NFTA_BITWISE_MASK], &priv->mask); + if (err < 0) + return err; + + err = nft_bitwise_extract_u32_data(tb[NFTA_BITWISE_XOR], &priv->xor); + if (err < 0) + return err; + + return 0; +} + +static int +nft_bitwise_fast_dump(struct sk_buff *skb, const struct nft_expr *expr) +{ + const struct nft_bitwise_fast_expr *priv = nft_expr_priv(expr); + struct nft_data data; + + if (nft_dump_register(skb, NFTA_BITWISE_SREG, priv->sreg)) + return -1; + if (nft_dump_register(skb, NFTA_BITWISE_DREG, priv->dreg)) + return -1; + if (nla_put_be32(skb, NFTA_BITWISE_LEN, htonl(sizeof(u32)))) + return -1; + if (nla_put_be32(skb, NFTA_BITWISE_OP, htonl(NFT_BITWISE_BOOL))) + return -1; + + data.data[0] = priv->mask; + if (nft_data_dump(skb, NFTA_BITWISE_MASK, &data, + NFT_DATA_VALUE, sizeof(u32)) < 0) + return -1; + + data.data[0] = priv->xor; + if (nft_data_dump(skb, NFTA_BITWISE_XOR, &data, + NFT_DATA_VALUE, sizeof(u32)) < 0) + return -1; + + return 0; +} + +static int nft_bitwise_fast_offload(struct nft_offload_ctx *ctx, + struct nft_flow_rule *flow, + const struct nft_expr *expr) +{ + const struct nft_bitwise_fast_expr *priv = nft_expr_priv(expr); + struct nft_offload_reg *reg = &ctx->regs[priv->dreg]; + + if (priv->xor || priv->sreg != priv->dreg || reg->len != sizeof(u32)) + return -EOPNOTSUPP; + + reg->mask.data[0] = priv->mask; + return 0; +} + +static bool nft_bitwise_fast_reduce(struct nft_regs_track *track, + const struct nft_expr *expr) +{ + const struct nft_bitwise_fast_expr *priv = nft_expr_priv(expr); + const struct nft_bitwise_fast_expr *bitwise; + + if (!track->regs[priv->sreg].selector) + return false; + + bitwise = nft_expr_priv(track->regs[priv->dreg].selector); + if (track->regs[priv->sreg].selector == track->regs[priv->dreg].selector && + track->regs[priv->dreg].bitwise && + track->regs[priv->dreg].bitwise->ops == expr->ops && + priv->sreg == bitwise->sreg && + priv->dreg == bitwise->dreg && + priv->mask == bitwise->mask && + priv->xor == bitwise->xor) { + track->cur = expr; + return true; + } + + if (track->regs[priv->sreg].bitwise) { + nft_reg_track_cancel(track, priv->dreg, NFT_REG32_SIZE); + return false; + } + + if (priv->sreg != priv->dreg) { + track->regs[priv->dreg].selector = + track->regs[priv->sreg].selector; + } + track->regs[priv->dreg].bitwise = expr; + + return false; +} + +const struct nft_expr_ops nft_bitwise_fast_ops = { + .type = &nft_bitwise_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_bitwise_fast_expr)), + .eval = NULL, /* inlined */ + .init = nft_bitwise_fast_init, + .dump = nft_bitwise_fast_dump, + .reduce = nft_bitwise_fast_reduce, + .offload = nft_bitwise_fast_offload, +}; + +static const struct nft_expr_ops * +nft_bitwise_select_ops(const struct nft_ctx *ctx, + const struct nlattr * const tb[]) +{ + int err; + u32 len; + + if (!tb[NFTA_BITWISE_LEN] || + !tb[NFTA_BITWISE_SREG] || + !tb[NFTA_BITWISE_DREG]) + return ERR_PTR(-EINVAL); + + err = nft_parse_u32_check(tb[NFTA_BITWISE_LEN], U8_MAX, &len); + if (err < 0) + return ERR_PTR(err); + + if (len != sizeof(u32)) + return &nft_bitwise_ops; + + if (tb[NFTA_BITWISE_OP] && + ntohl(nla_get_be32(tb[NFTA_BITWISE_OP])) != NFT_BITWISE_BOOL) + return &nft_bitwise_ops; + + return &nft_bitwise_fast_ops; +} + +struct nft_expr_type nft_bitwise_type __read_mostly = { + .name = "bitwise", + .select_ops = nft_bitwise_select_ops, + .policy = nft_bitwise_policy, + .maxattr = NFTA_BITWISE_MAX, + .owner = THIS_MODULE, +}; + +bool nft_expr_reduce_bitwise(struct nft_regs_track *track, + const struct nft_expr *expr) +{ + const struct nft_expr *last = track->last; + const struct nft_expr *next; + + if (expr == last) + return false; + + next = nft_expr_next(expr); + if (next->ops == &nft_bitwise_ops) + return nft_bitwise_reduce(track, next); + else if (next->ops == &nft_bitwise_fast_ops) + return nft_bitwise_fast_reduce(track, next); + + return false; +} +EXPORT_SYMBOL_GPL(nft_expr_reduce_bitwise); |