SysTutorials Posts

skb_tailroom – bytes at buffer end Synopsis int skb_tailroom(const struct sk_buff *skb); Arguments skb buffer to check Description Return the number of bytes of free space at the tail of an sk_buff Copyright

skb_store_bits – store bits from kernel buffer to skb Synopsis int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len); Arguments skb destination buffer offset offset in destination from source buffer len number of bytes to copy Description Copy the specified number of bytes from the source buffer to the destination skb. This function…

skb_split – Split fragmented skb to two parts at length len. Synopsis void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len); Arguments skb the buffer to split skb1 the buffer to receive the second part len new length for skb Copyright

skb_shared – is the buffer shared Synopsis int skb_shared(const struct sk_buff *skb); Arguments skb buffer to check Description Returns true if more than one person has a reference to this buffer. Copyright

skb_share_check – check if buffer is shared and if so clone it Synopsis struct sk_buff *skb_share_check(struct sk_buff *skb, gfp_t pri); Arguments skb buffer to check pri priority for memory allocation Description If the buffer is shared the buffer is cloned and the old copy drops a reference. A new clone with a single reference is…

skb_seq_read – Sequentially read skb data Synopsis unsigned int skb_seq_read(unsigned int consumed, const u8 **data, struct skb_seq_state *st); Arguments consumed number of bytes consumed by the caller so far data destination pointer for data to be returned st state variable Description Reads a block of skb data at consumed relative to the lower offset specified…

skb_segment – Perform protocol segmentation on skb. Synopsis struct sk_buff *skb_segment(struct sk_buff *head_skb, netdev_features_t features); Arguments head_skb buffer to segment features features for the output path (see dev->features) Description This function performs segmentation on the given skb. It returns a pointer to the first in a list of new skbs for the segments. In case…

skb_scrub_packet – scrub an skb Synopsis void skb_scrub_packet(struct sk_buff *skb, bool xnet); Arguments skb buffer to clean xnet packet is crossing netns Description skb_scrub_packet can be used after encapsulating or decapsulting a packet into/from a tunnel. Some information have to be cleared during these operations. skb_scrub_packet can also be used to clean a skb before…

skb_reserve – adjust headroom Synopsis void skb_reserve(struct sk_buff *skb, int len); Arguments skb buffer to alter len bytes to move Description Increase the headroom of an empty sk_buff by reducing the tail room. This is only allowed for an empty buffer. Copyright

skb_queue_tail – queue a buffer at the list tail Synopsis void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk); Arguments list list to use newsk buffer to queue Description Queue a buffer at the tail of the list. This function takes the list lock and can be used safely with other locking sk_buff functions safely. A buffer…

skb_queue_splice_tail_init – join two skb lists and reinitialise the emptied list Synopsis void skb_queue_splice_tail_init(struct sk_buff_head *list, struct sk_buff_head *head); Arguments list the new list to add head the place to add it in the first list Description Each of the lists is a queue. The list at list is reinitialised Copyright

skb_queue_splice_tail – join two skb lists, each list being a queue Synopsis void skb_queue_splice_tail(const struct sk_buff_head *list, struct sk_buff_head *head); Arguments list the new list to add head the place to add it in the first list Copyright

skb_queue_splice_init – join two skb lists and reinitialise the emptied list Synopsis void skb_queue_splice_init(struct sk_buff_head *list, struct sk_buff_head *head); Arguments list the new list to add head the place to add it in the first list Description The list at list is reinitialised Copyright

skb_queue_splice – join two skb lists, this is designed for stacks Synopsis void skb_queue_splice(const struct sk_buff_head *list, struct sk_buff_head *head); Arguments list the new list to add head the place to add it in the first list Copyright

skb_queue_purge – empty a list Synopsis void skb_queue_purge(struct sk_buff_head *list); Arguments list list to empty Description Delete all buffers on an sk_buff list. Each buffer is removed from the list and one reference dropped. This function takes the list lock and is atomic with respect to other list locking functions. Copyright

skb_queue_prev – return the prev packet in the queue Synopsis struct sk_buff *skb_queue_prev(const struct sk_buff_head *list, const struct sk_buff *skb); Arguments list queue head skb current buffer Description Return the prev packet in list before skb. It is only valid to call this if skb_queue_is_first evaluates to false. Copyright

skb_queue_next – return the next packet in the queue Synopsis struct sk_buff *skb_queue_next(const struct sk_buff_head *list, const struct sk_buff *skb); Arguments list queue head skb current buffer Description Return the next packet in list after skb. It is only valid to call this if skb_queue_is_last evaluates to false. Copyright

skb_queue_len – get queue length Synopsis __u32 skb_queue_len(const struct sk_buff_head * list_); Arguments list_ list to measure Description Return the length of an sk_buff queue. Copyright

skb_queue_is_last – check if skb is the last entry in the queue Synopsis bool skb_queue_is_last(const struct sk_buff_head * list, const struct sk_buff * skb); Arguments list queue head skb buffer Description Returns true if skb is the last buffer on the list. Copyright

skb_queue_is_first – check if skb is the first entry in the queue Synopsis bool skb_queue_is_first(const struct sk_buff_head * list, const struct sk_buff * skb); Arguments list queue head skb buffer Description Returns true if skb is the first buffer on the list. Copyright