diff options
Diffstat (limited to 'include/linux/skbuff.h')
| -rw-r--r-- | include/linux/skbuff.h | 154 |
1 files changed, 130 insertions, 24 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 9b3802a197a..8eaa62400fc 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -47,11 +47,29 @@ * * The hardware you're dealing with doesn't calculate the full checksum * (as in CHECKSUM_COMPLETE), but it does parse headers and verify checksums - * for specific protocols e.g. TCP/UDP/SCTP, then, for such packets it will - * set CHECKSUM_UNNECESSARY if their checksums are okay. skb->csum is still - * undefined in this case though. It is a bad option, but, unfortunately, - * nowadays most vendors do this. Apparently with the secret goal to sell - * you new devices, when you will add new protocol to your host, f.e. IPv6 8) + * for specific protocols. For such packets it will set CHECKSUM_UNNECESSARY + * if their checksums are okay. skb->csum is still undefined in this case + * though. It is a bad option, but, unfortunately, nowadays most vendors do + * this. Apparently with the secret goal to sell you new devices, when you + * will add new protocol to your host, f.e. IPv6 8) + * + * CHECKSUM_UNNECESSARY is applicable to following protocols: + * TCP: IPv6 and IPv4. + * UDP: IPv4 and IPv6. A device may apply CHECKSUM_UNNECESSARY to a + * zero UDP checksum for either IPv4 or IPv6, the networking stack + * may perform further validation in this case. + * GRE: only if the checksum is present in the header. + * SCTP: indicates the CRC in SCTP header has been validated. + * + * skb->csum_level indicates the number of consecutive checksums found in + * the packet minus one that have been verified as CHECKSUM_UNNECESSARY. + * For instance if a device receives an IPv6->UDP->GRE->IPv4->TCP packet + * and a device is able to verify the checksums for UDP (possibly zero), + * GRE (checksum flag is set), and TCP-- skb->csum_level would be set to + * two. If the device were only able to verify the UDP checksum and not + * GRE, either because it doesn't support GRE checksum of because GRE + * checksum is bad, skb->csum_level would be set to zero (TCP checksum is + * not considered in this case). * * CHECKSUM_COMPLETE: * @@ -112,6 +130,9 @@ #define CHECKSUM_COMPLETE 2 #define CHECKSUM_PARTIAL 3 +/* Maximum value in skb->csum_level */ +#define SKB_MAX_CSUM_LEVEL 3 + #define SKB_DATA_ALIGN(X) ALIGN(X, SMP_CACHE_BYTES) #define SKB_WITH_OVERHEAD(X) \ ((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) @@ -527,6 +548,16 @@ struct sk_buff { ip_summed:2, nohdr:1, nfctinfo:3; + +/* if you move pkt_type around you also must adapt those constants */ +#ifdef __BIG_ENDIAN_BITFIELD +#define PKT_TYPE_MAX (7 << 5) +#else +#define PKT_TYPE_MAX 7 +#endif +#define PKT_TYPE_OFFSET() offsetof(struct sk_buff, __pkt_type_offset) + + __u8 __pkt_type_offset[0]; __u8 pkt_type:3, fclone:2, ipvs_property:1, @@ -571,16 +602,12 @@ struct sk_buff { __u8 wifi_acked:1; __u8 no_fcs:1; __u8 head_frag:1; - /* Encapsulation protocol and NIC drivers should use - * this flag to indicate to each other if the skb contains - * encapsulated packet or not and maybe use the inner packet - * headers if needed - */ + /* Indicates the inner headers are valid in the skbuff. */ __u8 encapsulation:1; __u8 encap_hdr_csum:1; __u8 csum_valid:1; __u8 csum_complete_sw:1; - /* 2/4 bit hole (depending on ndisc_nodetype presence) */ + /* 1/3 bit hole (depending on ndisc_nodetype presence) */ kmemcheck_bitfield_end(flags2); #if defined CONFIG_NET_DMA || defined CONFIG_NET_RX_BUSY_POLL @@ -598,6 +625,12 @@ struct sk_buff { __u32 reserved_tailroom; }; + kmemcheck_bitfield_begin(flags3); + __u8 csum_level:2; + __u8 csum_bad:1; + /* 13 bit hole */ + kmemcheck_bitfield_end(flags3); + __be16 inner_protocol; __u16 inner_transport_header; __u16 inner_network_header; @@ -736,6 +769,12 @@ static inline struct sk_buff *alloc_skb(unsigned int size, return __alloc_skb(size, priority, 0, NUMA_NO_NODE); } +struct sk_buff *alloc_skb_with_frags(unsigned long header_len, + unsigned long data_len, + int max_page_order, + int *errcode, + gfp_t gfp_mask); + static inline struct sk_buff *alloc_skb_fclone(unsigned int size, gfp_t priority) { @@ -1044,6 +1083,7 @@ static inline int skb_header_cloned(const struct sk_buff *skb) * Drop a reference to the header part of the buffer. This is done * by acquiring a payload reference. You must not read from the header * part of skb->data after this. + * Note : Check if you can use __skb_header_release() instead. */ static inline void skb_header_release(struct sk_buff *skb) { @@ -1053,6 +1093,20 @@ static inline void skb_header_release(struct sk_buff *skb) } /** + * __skb_header_release - release reference to header + * @skb: buffer to operate on + * + * Variant of skb_header_release() assuming skb is private to caller. + * We can avoid one atomic operation. + */ +static inline void __skb_header_release(struct sk_buff *skb) +{ + skb->nohdr = 1; + atomic_set(&skb_shinfo(skb)->dataref, 1 + (1 << SKB_DATAREF_SHIFT)); +} + + +/** * skb_shared - is the buffer shared * @skb: buffer to check * @@ -1862,18 +1916,6 @@ static inline int pskb_network_may_pull(struct sk_buff *skb, unsigned int len) return pskb_may_pull(skb, skb_network_offset(skb) + len); } -static inline void skb_pop_rcv_encapsulation(struct sk_buff *skb) -{ - /* Only continue with checksum unnecessary if device indicated - * it is valid across encapsulation (skb->encapsulation was set). - */ - if (skb->ip_summed == CHECKSUM_UNNECESSARY && !skb->encapsulation) - skb->ip_summed = CHECKSUM_NONE; - - skb->encapsulation = 0; - skb->csum_valid = 0; -} - /* * CPUs often take a performance hit when accessing unaligned memory * locations. The actual performance hit varies, it can be small if the @@ -2679,6 +2721,8 @@ static inline ktime_t net_invalid_timestamp(void) return ktime_set(0, 0); } +struct sk_buff *skb_clone_sk(struct sk_buff *skb); + #ifdef CONFIG_NETWORK_PHY_TIMESTAMPING void skb_clone_tx_timestamp(struct sk_buff *skb); @@ -2794,6 +2838,42 @@ static inline __sum16 skb_checksum_complete(struct sk_buff *skb) 0 : __skb_checksum_complete(skb); } +static inline void __skb_decr_checksum_unnecessary(struct sk_buff *skb) +{ + if (skb->ip_summed == CHECKSUM_UNNECESSARY) { + if (skb->csum_level == 0) + skb->ip_summed = CHECKSUM_NONE; + else + skb->csum_level--; + } +} + +static inline void __skb_incr_checksum_unnecessary(struct sk_buff *skb) +{ + if (skb->ip_summed == CHECKSUM_UNNECESSARY) { + if (skb->csum_level < SKB_MAX_CSUM_LEVEL) + skb->csum_level++; + } else if (skb->ip_summed == CHECKSUM_NONE) { + skb->ip_summed = CHECKSUM_UNNECESSARY; + skb->csum_level = 0; + } +} + +static inline void __skb_mark_checksum_bad(struct sk_buff *skb) +{ + /* Mark current checksum as bad (typically called from GRO + * path). In the case that ip_summed is CHECKSUM_NONE + * this must be the first checksum encountered in the packet. + * When ip_summed is CHECKSUM_UNNECESSARY, this is the first + * checksum after the last one validated. For UDP, a zero + * checksum can not be marked as bad. + */ + + if (skb->ip_summed == CHECKSUM_NONE || + skb->ip_summed == CHECKSUM_UNNECESSARY) + skb->csum_bad = 1; +} + /* Check if we need to perform checksum complete validation. * * Returns true if checksum complete is needed, false otherwise @@ -2805,6 +2885,7 @@ static inline bool __skb_checksum_validate_needed(struct sk_buff *skb, { if (skb_csum_unnecessary(skb) || (zero_okay && !check)) { skb->csum_valid = 1; + __skb_decr_checksum_unnecessary(skb); return false; } @@ -2834,6 +2915,9 @@ static inline __sum16 __skb_checksum_validate_complete(struct sk_buff *skb, skb->csum_valid = 1; return 0; } + } else if (skb->csum_bad) { + /* ip_summed == CHECKSUM_NONE in this case */ + return 1; } skb->csum = psum; @@ -2891,6 +2975,26 @@ static inline __wsum null_compute_pseudo(struct sk_buff *skb, int proto) #define skb_checksum_simple_validate(skb) \ __skb_checksum_validate(skb, 0, true, false, 0, null_compute_pseudo) +static inline bool __skb_checksum_convert_check(struct sk_buff *skb) +{ + return (skb->ip_summed == CHECKSUM_NONE && + skb->csum_valid && !skb->csum_bad); +} + +static inline void __skb_checksum_convert(struct sk_buff *skb, + __sum16 check, __wsum pseudo) +{ + skb->csum = ~pseudo; + skb->ip_summed = CHECKSUM_COMPLETE; +} + +#define skb_checksum_try_convert(skb, proto, check, compute_pseudo) \ +do { \ + if (__skb_checksum_convert_check(skb)) \ + __skb_checksum_convert(skb, check, \ + compute_pseudo(skb, proto)); \ +} while (0) + #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) void nf_conntrack_destroy(struct nf_conntrack *nfct); static inline void nf_conntrack_put(struct nf_conntrack *nfct) @@ -3145,7 +3249,9 @@ bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off); int skb_checksum_setup(struct sk_buff *skb, bool recalculate); -u32 __skb_get_poff(const struct sk_buff *skb); +u32 skb_get_poff(const struct sk_buff *skb); +u32 __skb_get_poff(const struct sk_buff *skb, void *data, + const struct flow_keys *keys, int hlen); /** * skb_head_is_locked - Determine if the skb->head is locked down |