/* SPDX-License-Identifier: GPL-2.0-or-later */ #ifndef _NET_IPV6_GRO_H #define _NET_IPV6_GRO_H #include <linux/indirect_call_wrapper.h> #include <linux/ip.h> #include <linux/ipv6.h> #include <net/ip6_checksum.h> #include <linux/skbuff.h> #include <net/udp.h> struct napi_gro_cb { /* Virtual address of skb_shinfo(skb)->frags[0].page + offset. */ void *frag0; /* Length of frag0. */ unsigned int frag0_len; /* This indicates where we are processing relative to skb->data. */ int data_offset; /* This is non-zero if the packet cannot be merged with the new skb. */ u16 flush; /* Save the IP ID here and check when we get to the transport layer */ u16 flush_id; /* Number of segments aggregated. */ u16 count; /* Used in ipv6_gro_receive() and foo-over-udp */ u16 proto; /* jiffies when first packet was created/queued */ unsigned long age; /* Used in napi_gro_cb::free */ #define NAPI_GRO_FREE 1 #define NAPI_GRO_FREE_STOLEN_HEAD 2 /* portion of the cb set to zero at every gro iteration */ struct_group(zeroed, /* Start offset for remote checksum offload */ u16 gro_remcsum_start; /* This is non-zero if the packet may be of the same flow. */ u8 same_flow:1; /* Used in tunnel GRO receive */ u8 encap_mark:1; /* GRO checksum is valid */ u8 csum_valid:1; /* Number of checksums via CHECKSUM_UNNECESSARY */ u8 csum_cnt:3; /* Free the skb? */ u8 free:2; /* Used in foo-over-udp, set in udp[46]_gro_receive */ u8 is_ipv6:1; /* Used in GRE, set in fou/gue_gro_receive */ u8 is_fou:1; /* Used to determine if flush_id can be ignored */ u8 is_atomic:1; /* Number of gro_receive callbacks this packet already went through */ u8 recursion_counter:4; /* GRO is done by frag_list pointer chaining. */ u8 is_flist:1; ); /* used to support CHECKSUM_COMPLETE for tunneling protocols */ __wsum csum; /* used in skb_gro_receive() slow path */ struct sk_buff *last; }; #define NAPI_GRO_CB(skb) ((struct napi_gro_cb *)(skb)->cb) #define GRO_RECURSION_LIMIT 15 static inline int gro_recursion_inc_test(struct sk_buff *skb) { return ++NAPI_GRO_CB(skb)->recursion_counter == GRO_RECURSION_LIMIT; } typedef struct sk_buff *(*gro_receive_t)(struct list_head *, struct sk_buff *); static inline struct sk_buff *call_gro_receive(gro_receive_t cb, struct list_head *head, struct sk_buff *skb) { if (unlikely(gro_recursion_inc_test(skb))) { NAPI_GRO_CB(skb)->flush |= 1; return NULL; } return cb(head, skb); } typedef struct sk_buff *(*gro_receive_sk_t)(struct sock *, struct list_head *, struct sk_buff *); static inline struct sk_buff *call_gro_receive_sk(gro_receive_sk_t cb, struct sock *sk, struct list_head *head, struct sk_buff *skb) { if (unlikely(gro_recursion_inc_test(skb))) { NAPI_GRO_CB(skb)->flush |= 1; return NULL; } return cb(sk, head, skb); } static inline unsigned int skb_gro_offset(const struct sk_buff *skb) { return NAPI_GRO_CB(skb)->data_offset; } static inline unsigned int skb_gro_len(const struct sk_buff *skb) { return skb->len - NAPI_GRO_CB(skb)->data_offset; } static inline void skb_gro_pull(struct sk_buff *skb, unsigned int len) { NAPI_GRO_CB(skb)->data_offset += len; } static inline void *skb_gro_header_fast(struct sk_buff *skb, unsigned int offset) { return NAPI_GRO_CB(skb)->frag0 + offset; } static inline int skb_gro_header_hard(struct sk_buff *skb, unsigned int hlen) { return NAPI_GRO_CB(skb)->frag0_len < hlen; } static inline void skb_gro_frag0_invalidate(struct sk_buff *skb) { NAPI_GRO_CB(skb)->frag0 = NULL; NAPI_GRO_CB(skb)->frag0_len = 0; } static inline void *skb_gro_header_slow(struct sk_buff *skb, unsigned int hlen, unsigned int offset) { if (!pskb_may_pull(skb, hlen)) return NULL; skb_gro_frag0_invalidate(skb); return skb->data + offset; } static inline void *skb_gro_header(struct sk_buff *skb, unsigned int hlen, unsigned int offset) { void *ptr; ptr = skb_gro_header_fast(skb, offset); if (skb_gro_header_hard(skb, hlen)) ptr = skb_gro_header_slow(skb, hlen, offset); return ptr; } static inline void *skb_gro_network_header(struct sk_buff *skb) { return (NAPI_GRO_CB(skb)->frag0 ?: skb->data) + skb_network_offset(skb); } static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto) { const struct iphdr *iph = skb_gro_network_header(skb); return csum_tcpudp_nofold(iph->saddr, iph->daddr, skb_gro_len(skb), proto, 0); } static inline void skb_gro_postpull_rcsum(struct sk_buff *skb, const void *start, unsigned int len) { if (NAPI_GRO_CB(skb)->csum_valid) NAPI_GRO_CB(skb)->csum = wsum_negate(csum_partial(start, len, wsum_negate(NAPI_GRO_CB(skb)->csum))); } /* GRO checksum functions. These are logical equivalents of the normal * checksum functions (in skbuff.h) except that they operate on the GRO * offsets and fields in sk_buff. */ __sum16 __skb_gro_checksum_complete(struct sk_buff *skb); static inline bool skb_at_gro_remcsum_start(struct sk_buff *skb) { return (NAPI_GRO_CB(skb)->gro_remcsum_start == skb_gro_offset(skb)); } static inline bool __skb_gro_checksum_validate_needed(struct sk_buff *skb, bool zero_okay, __sum16 check) { return ((skb->ip_summed != CHECKSUM_PARTIAL || skb_checksum_start_offset(skb) < skb_gro_offset(skb)) && !skb_at_gro_remcsum_start(skb) && NAPI_GRO_CB(skb)->csum_cnt == 0 && (!zero_okay || check)); } static inline __sum16 __skb_gro_checksum_validate_complete(struct sk_buff *skb, __wsum psum) { if (NAPI_GRO_CB(skb)->csum_valid && !csum_fold(csum_add(psum, NAPI_GRO_CB(skb)->csum))) return 0; NAPI_GRO_CB(skb)->csum = psum; return __skb_gro_checksum_complete(skb); } static inline void skb_gro_incr_csum_unnecessary(struct sk_buff *skb) { if (NAPI_GRO_CB(skb)->csum_cnt > 0) { /* Consume a checksum from CHECKSUM_UNNECESSARY */ NAPI_GRO_CB(skb)->csum_cnt--; } else { /* Update skb for CHECKSUM_UNNECESSARY and csum_level when we * verified a new top level checksum or an encapsulated one * during GRO. This saves work if we fallback to normal path. */ __skb_incr_checksum_unnecessary(skb); } } #define __skb_gro_checksum_validate(skb, proto, zero_okay, check, \ compute_pseudo) \ ({ \ __sum16 __ret = 0; \ if (__skb_gro_checksum_validate_needed(skb, zero_okay, check)) \ __ret = __skb_gro_checksum_validate_complete(skb, \ compute_pseudo(skb, proto)); \ if (!__ret) \ skb_gro_incr_csum_unnecessary(skb); \ __ret; \ }) #define skb_gro_checksum_validate(skb, proto, compute_pseudo) \ __skb_gro_checksum_validate(skb, proto, false, 0, compute_pseudo) #define skb_gro_checksum_validate_zero_check(skb, proto, check, \ compute_pseudo) \ __skb_gro_checksum_validate(skb, proto, true, check, compute_pseudo) #define skb_gro_checksum_simple_validate(skb) \ __skb_gro_checksum_validate(skb, 0, false, 0, null_compute_pseudo) static inline bool __skb_gro_checksum_convert_check(struct sk_buff *skb) { return (NAPI_GRO_CB(skb)->csum_cnt == 0 && !NAPI_GRO_CB(skb)->csum_valid); } static inline void __skb_gro_checksum_convert(struct sk_buff *skb, __wsum pseudo) { NAPI_GRO_CB(skb)->csum = ~pseudo; NAPI_GRO_CB(skb)->csum_valid = 1; } #define skb_gro_checksum_try_convert(skb, proto, compute_pseudo) \ do { \ if (__skb_gro_checksum_convert_check(skb)) \ __skb_gro_checksum_convert(skb, \ compute_pseudo(skb, proto)); \ } while (0) struct gro_remcsum { int offset; __wsum delta; }; static inline void skb_gro_remcsum_init(struct gro_remcsum *grc) { grc->offset = 0; grc->delta = 0; } static inline void *skb_gro_remcsum_process(struct sk_buff *skb, void *ptr, unsigned int off, size_t hdrlen, int start, int offset, struct gro_remcsum *grc, bool nopartial) { __wsum delta; size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start); BUG_ON(!NAPI_GRO_CB(skb)->csum_valid); if (!nopartial) { NAPI_GRO_CB(skb)->gro_remcsum_start = off + hdrlen + start; return ptr; } ptr = skb_gro_header(skb, off + plen, off); if (!ptr) return NULL; delta = remcsum_adjust(ptr + hdrlen, NAPI_GRO_CB(skb)->csum, start, offset); /* Adjust skb->csum since we changed the packet */ NAPI_GRO_CB(skb)->csum = csum_add(NAPI_GRO_CB(skb)->csum, delta); grc->offset = off + hdrlen + offset; grc->delta = delta; return ptr; } static inline void skb_gro_remcsum_cleanup(struct sk_buff *skb, struct gro_remcsum *grc) { void *ptr; size_t plen = grc->offset + sizeof(u16); if (!grc->delta) return; ptr = skb_gro_header(skb, plen, grc->offset); if (!ptr) return; remcsum_unadjust((__sum16 *)ptr, grc->delta); } #ifdef CONFIG_XFRM_OFFLOAD static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff *pp, int flush) { if (PTR_ERR(pp) != -EINPROGRESS) NAPI_GRO_CB(skb)->flush |= flush; } static inline void skb_gro_flush_final_remcsum(struct sk_buff *skb, struct sk_buff *pp, int flush, struct gro_remcsum *grc) { if (PTR_ERR(pp) != -EINPROGRESS) { NAPI_GRO_CB(skb)->flush |= flush; skb_gro_remcsum_cleanup(skb, grc); skb->remcsum_offload = 0; } } #else static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff *pp, int flush) { NAPI_GRO_CB(skb)->flush |= flush; } static inline void skb_gro_flush_final_remcsum(struct sk_buff *skb, struct sk_buff *pp, int flush, struct gro_remcsum *grc) { NAPI_GRO_CB(skb)->flush |= flush; skb_gro_remcsum_cleanup(skb, grc); skb->remcsum_offload = 0; } #endif INDIRECT_CALLABLE_DECLARE(struct sk_buff *ipv6_gro_receive(struct list_head *, struct sk_buff *)); INDIRECT_CALLABLE_DECLARE(int ipv6_gro_complete(struct sk_buff *, int)); INDIRECT_CALLABLE_DECLARE(struct sk_buff *inet_gro_receive(struct list_head *, struct sk_buff *)); INDIRECT_CALLABLE_DECLARE(int inet_gro_complete(struct sk_buff *, int)); INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp4_gro_receive(struct list_head *, struct sk_buff *)); INDIRECT_CALLABLE_DECLARE(int udp4_gro_complete(struct sk_buff *, int)); INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp6_gro_receive(struct list_head *, struct sk_buff *)); INDIRECT_CALLABLE_DECLARE(int udp6_gro_complete(struct sk_buff *, int)); #define indirect_call_gro_receive_inet(cb, f2, f1, head, skb) \ ({ \ unlikely(gro_recursion_inc_test(skb)) ? \ NAPI_GRO_CB(skb)->flush |= 1, NULL : \ INDIRECT_CALL_INET(cb, f2, f1, head, skb); \ }) struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb, struct udphdr *uh, struct sock *sk); int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup); static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb) { struct udphdr *uh; unsigned int hlen, off; off = skb_gro_offset(skb); hlen = off + sizeof(*uh); uh = skb_gro_header(skb, hlen, off); return uh; } static inline __wsum ip6_gro_compute_pseudo(struct sk_buff *skb, int proto) { const struct ipv6hdr *iph = skb_gro_network_header(skb); return ~csum_unfold(csum_ipv6_magic(&iph->saddr, &iph->daddr, skb_gro_len(skb), proto, 0)); } int skb_gro_receive(struct sk_buff *p, struct sk_buff *skb); /* Pass the currently batched GRO_NORMAL SKBs up to the stack. */ static inline void gro_normal_list(struct napi_struct *napi) { if (!napi->rx_count) return; netif_receive_skb_list_internal(&napi->rx_list); INIT_LIST_HEAD(&napi->rx_list); napi->rx_count = 0; } /* Queue one GRO_NORMAL SKB up for list processing. If batch size exceeded, * pass the whole batch up to the stack. */ static inline void gro_normal_one(struct napi_struct *napi, struct sk_buff *skb, int segs) { list_add_tail(&skb->list, &napi->rx_list); napi->rx_count += segs; if (napi->rx_count >= READ_ONCE(gro_normal_batch)) gro_normal_list(napi); } #endif /* _NET_IPV6_GRO_H */