From 2f7c68cb55ecb7331f2381deb497c27155f32faf Mon Sep 17 00:00:00 2001 From: hc <hc@nodka.com> Date: Wed, 03 Jan 2024 09:43:39 +0000 Subject: [PATCH] update kernel to 5.10.198 --- kernel/net/netfilter/nft_exthdr.c | 193 +++++++++++++++++++++++++++++++++++++++++++---- 1 files changed, 174 insertions(+), 19 deletions(-) diff --git a/kernel/net/netfilter/nft_exthdr.c b/kernel/net/netfilter/nft_exthdr.c index 670dd14..cb69a29 100644 --- a/kernel/net/netfilter/nft_exthdr.c +++ b/kernel/net/netfilter/nft_exthdr.c @@ -10,8 +10,10 @@ #include <linux/netlink.h> #include <linux/netfilter.h> #include <linux/netfilter/nf_tables.h> +#include <linux/sctp.h> #include <net/netfilter/nf_tables_core.h> #include <net/netfilter/nf_tables.h> +#include <net/sctp/sctp.h> #include <net/tcp.h> struct nft_exthdr { @@ -31,6 +33,14 @@ return 1; else return opt[offset + 1]; +} + +static int nft_skb_copy_to_reg(const struct sk_buff *skb, int offset, u32 *dest, unsigned int len) +{ + if (len % NFT_REG32_SIZE) + dest[len / NFT_REG32_SIZE] = 0; + + return skb_copy_bits(skb, offset, dest, len); } static void nft_exthdr_ipv6_eval(const struct nft_expr *expr, @@ -54,8 +64,7 @@ } offset += priv->offset; - dest[priv->len / NFT_REG32_SIZE] = 0; - if (skb_copy_bits(pkt->skb, offset, dest, priv->len) < 0) + if (nft_skb_copy_to_reg(pkt->skb, offset, dest, priv->len) < 0) goto err; return; err: @@ -151,8 +160,7 @@ } offset += priv->offset; - dest[priv->len / NFT_REG32_SIZE] = 0; - if (skb_copy_bits(pkt->skb, offset, dest, priv->len) < 0) + if (nft_skb_copy_to_reg(pkt->skb, offset, dest, priv->len) < 0) goto err; return; err: @@ -168,7 +176,7 @@ if (!pkt->tprot_set || pkt->tprot != IPPROTO_TCP) return NULL; - tcph = skb_header_pointer(pkt->skb, pkt->xt.thoff, sizeof(*tcph), buffer); + tcph = skb_header_pointer(pkt->skb, nft_thoff(pkt), sizeof(*tcph), buffer); if (!tcph) return NULL; @@ -176,7 +184,7 @@ if (*tcphdr_len < sizeof(*tcph) || *tcphdr_len > len) return NULL; - return skb_header_pointer(pkt->skb, pkt->xt.thoff, *tcphdr_len, buffer); + return skb_header_pointer(pkt->skb, nft_thoff(pkt), *tcphdr_len, buffer); } static void nft_exthdr_tcp_eval(const struct nft_expr *expr, @@ -208,7 +216,8 @@ if (priv->flags & NFT_EXTHDR_F_PRESENT) { *dest = 1; } else { - dest[priv->len / NFT_REG32_SIZE] = 0; + if (priv->len % NFT_REG32_SIZE) + dest[priv->len / NFT_REG32_SIZE] = 0; memcpy(dest, opt + offset, priv->len); } @@ -234,9 +243,14 @@ tcph = nft_tcp_header_pointer(pkt, sizeof(buff), buff, &tcphdr_len); if (!tcph) - return; + goto err; + if (skb_ensure_writable(pkt->skb, nft_thoff(pkt) + tcphdr_len)) + goto err; + + tcph = (struct tcphdr *)(pkt->skb->data + nft_thoff(pkt)); opt = (u8 *)tcph; + for (i = sizeof(*tcph); i < tcphdr_len - 1; i += optl) { union { __be16 v16; @@ -249,16 +263,7 @@ continue; if (i + optl > tcphdr_len || priv->len + priv->offset > optl) - return; - - if (skb_ensure_writable(pkt->skb, - pkt->xt.thoff + i + priv->len)) - return; - - tcph = nft_tcp_header_pointer(pkt, sizeof(buff), buff, - &tcphdr_len); - if (!tcph) - return; + goto err; offset = i + priv->offset; @@ -301,6 +306,107 @@ return; } + return; +err: + regs->verdict.code = NFT_BREAK; +} + +static void nft_exthdr_tcp_strip_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + u8 buff[sizeof(struct tcphdr) + MAX_TCP_OPTION_SPACE]; + struct nft_exthdr *priv = nft_expr_priv(expr); + unsigned int i, tcphdr_len, optl; + struct tcphdr *tcph; + u8 *opt; + + tcph = nft_tcp_header_pointer(pkt, sizeof(buff), buff, &tcphdr_len); + if (!tcph) + goto err; + + if (skb_ensure_writable(pkt->skb, nft_thoff(pkt) + tcphdr_len)) + goto drop; + + tcph = (struct tcphdr *)(pkt->skb->data + nft_thoff(pkt)); + opt = (u8 *)tcph; + + for (i = sizeof(*tcph); i < tcphdr_len - 1; i += optl) { + unsigned int j; + + optl = optlen(opt, i); + if (priv->type != opt[i]) + continue; + + if (i + optl > tcphdr_len) + goto drop; + + for (j = 0; j < optl; ++j) { + u16 n = TCPOPT_NOP; + u16 o = opt[i+j]; + + if ((i + j) % 2 == 0) { + o <<= 8; + n <<= 8; + } + inet_proto_csum_replace2(&tcph->check, pkt->skb, htons(o), + htons(n), false); + } + memset(opt + i, TCPOPT_NOP, optl); + return; + } + + /* option not found, continue. This allows to do multiple + * option removals per rule. + */ + return; +err: + regs->verdict.code = NFT_BREAK; + return; +drop: + /* can't remove, no choice but to drop */ + regs->verdict.code = NF_DROP; +} + +static void nft_exthdr_sctp_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + unsigned int offset = nft_thoff(pkt) + sizeof(struct sctphdr); + struct nft_exthdr *priv = nft_expr_priv(expr); + u32 *dest = ®s->data[priv->dreg]; + const struct sctp_chunkhdr *sch; + struct sctp_chunkhdr _sch; + + if (pkt->tprot != IPPROTO_SCTP) + goto err; + + do { + sch = skb_header_pointer(pkt->skb, offset, sizeof(_sch), &_sch); + if (!sch || !sch->length) + break; + + if (sch->type == priv->type) { + if (priv->flags & NFT_EXTHDR_F_PRESENT) { + nft_reg_store8(dest, true); + return; + } + if (priv->offset + priv->len > ntohs(sch->length) || + offset + ntohs(sch->length) > pkt->skb->len) + break; + + if (nft_skb_copy_to_reg(pkt->skb, offset + priv->offset, + dest, priv->len) < 0) + break; + return; + } + offset += SCTP_PAD4(ntohs(sch->length)); + } while (offset < pkt->skb->len); +err: + if (priv->flags & NFT_EXTHDR_F_PRESENT) + nft_reg_store8(dest, false); + else + regs->verdict.code = NFT_BREAK; } static const struct nla_policy nft_exthdr_policy[NFTA_EXTHDR_MAX + 1] = { @@ -410,6 +516,28 @@ priv->len); } +static int nft_exthdr_tcp_strip_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_exthdr *priv = nft_expr_priv(expr); + + if (tb[NFTA_EXTHDR_SREG] || + tb[NFTA_EXTHDR_DREG] || + tb[NFTA_EXTHDR_FLAGS] || + tb[NFTA_EXTHDR_OFFSET] || + tb[NFTA_EXTHDR_LEN]) + return -EINVAL; + + if (!tb[NFTA_EXTHDR_TYPE]) + return -EINVAL; + + priv->type = nla_get_u8(tb[NFTA_EXTHDR_TYPE]); + priv->op = NFT_EXTHDR_OP_TCPOPT; + + return 0; +} + static int nft_exthdr_ipv4_init(const struct nft_ctx *ctx, const struct nft_expr *expr, const struct nlattr * const tb[]) @@ -470,6 +598,13 @@ return nft_exthdr_dump_common(skb, priv); } +static int nft_exthdr_dump_strip(struct sk_buff *skb, const struct nft_expr *expr) +{ + const struct nft_exthdr *priv = nft_expr_priv(expr); + + return nft_exthdr_dump_common(skb, priv); +} + static const struct nft_expr_ops nft_exthdr_ipv6_ops = { .type = &nft_exthdr_type, .size = NFT_EXPR_SIZE(sizeof(struct nft_exthdr)), @@ -502,6 +637,22 @@ .dump = nft_exthdr_dump_set, }; +static const struct nft_expr_ops nft_exthdr_tcp_strip_ops = { + .type = &nft_exthdr_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_exthdr)), + .eval = nft_exthdr_tcp_strip_eval, + .init = nft_exthdr_tcp_strip_init, + .dump = nft_exthdr_dump_strip, +}; + +static const struct nft_expr_ops nft_exthdr_sctp_ops = { + .type = &nft_exthdr_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_exthdr)), + .eval = nft_exthdr_sctp_eval, + .init = nft_exthdr_init, + .dump = nft_exthdr_dump, +}; + static const struct nft_expr_ops * nft_exthdr_select_ops(const struct nft_ctx *ctx, const struct nlattr * const tb[]) @@ -521,7 +672,7 @@ return &nft_exthdr_tcp_set_ops; if (tb[NFTA_EXTHDR_DREG]) return &nft_exthdr_tcp_ops; - break; + return &nft_exthdr_tcp_strip_ops; case NFT_EXTHDR_OP_IPV6: if (tb[NFTA_EXTHDR_DREG]) return &nft_exthdr_ipv6_ops; @@ -532,6 +683,10 @@ return &nft_exthdr_ipv4_ops; } break; + case NFT_EXTHDR_OP_SCTP: + if (tb[NFTA_EXTHDR_DREG]) + return &nft_exthdr_sctp_ops; + break; } return ERR_PTR(-EOPNOTSUPP); -- Gitblit v1.6.2