/* SCTP kernel implementation * (C) Copyright IBM Corp. 2001, 2004 * Copyright (c) 1999-2000 Cisco, Inc. * Copyright (c) 1999-2001 Motorola, Inc. * Copyright (c) 2001 Intel Corp. * Copyright (c) 2001 Nokia, Inc. * Copyright (c) 2001 La Monte H.P. Yarroll * * These functions manipulate an sctp event. The struct ulpevent is used * to carry notifications and data to the ULP (sockets). * * This SCTP implementation is free software; * you can redistribute it and/or modify it under the terms of * the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * * This SCTP implementation is distributed in the hope that it * will be useful, but WITHOUT ANY WARRANTY; without even the implied * ************************ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. * See the GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with GNU CC; see the file COPYING. If not, see * . * * Please send any bug reports or fixes you make to the * email address(es): * lksctp developers * * Written or modified by: * Jon Grimm * La Monte H.P. Yarroll * Ardelle Fan * Sridhar Samudrala */ #include #include #include #include #include #include static void sctp_ulpevent_receive_data(struct sctp_ulpevent *event, struct sctp_association *asoc); static void sctp_ulpevent_release_data(struct sctp_ulpevent *event); static void sctp_ulpevent_release_frag_data(struct sctp_ulpevent *event); /* Initialize an ULP event from an given skb. */ static void sctp_ulpevent_init(struct sctp_ulpevent *event, __u16 msg_flags, unsigned int len) { memset(event, 0, sizeof(struct sctp_ulpevent)); event->msg_flags = msg_flags; event->rmem_len = len; } /* Create a new sctp_ulpevent. */ static struct sctp_ulpevent *sctp_ulpevent_new(int size, __u16 msg_flags, gfp_t gfp) { struct sctp_ulpevent *event; struct sk_buff *skb; skb = alloc_skb(size, gfp); if (!skb) goto fail; event = sctp_skb2event(skb); sctp_ulpevent_init(event, msg_flags, skb->truesize); return event; fail: return NULL; } /* Is this a MSG_NOTIFICATION? */ int sctp_ulpevent_is_notification(const struct sctp_ulpevent *event) { return MSG_NOTIFICATION == (event->msg_flags & MSG_NOTIFICATION); } /* Hold the association in case the msg_name needs read out of * the association. */ static inline void sctp_ulpevent_set_owner(struct sctp_ulpevent *event, const struct sctp_association *asoc) { struct sctp_chunk *chunk = event->chunk; struct sk_buff *skb; /* Cast away the const, as we are just wanting to * bump the reference count. */ sctp_association_hold((struct sctp_association *)asoc); skb = sctp_event2skb(event); event->asoc = (struct sctp_association *)asoc; atomic_add(event->rmem_len, &event->asoc->rmem_alloc); sctp_skb_set_owner_r(skb, asoc->base.sk); if (chunk && chunk->head_skb && !chunk->head_skb->sk) chunk->head_skb->sk = asoc->base.sk; } /* A simple destructor to give up the reference to the association. */ static inline void sctp_ulpevent_release_owner(struct sctp_ulpevent *event) { struct sctp_association *asoc = event->asoc; atomic_sub(event->rmem_len, &asoc->rmem_alloc); sctp_association_put(asoc); } /* Create and initialize an SCTP_ASSOC_CHANGE event. * * 5.3.1.1 SCTP_ASSOC_CHANGE * * Communication notifications inform the ULP that an SCTP association * has either begun or ended. The identifier for a new association is * provided by this notification. * * Note: There is no field checking here. If a field is unused it will be * zero'd out. */ struct sctp_ulpevent *sctp_ulpevent_make_assoc_change( const struct sctp_association *asoc, __u16 flags, __u16 state, __u16 error, __u16 outbound, __u16 inbound, struct sctp_chunk *chunk, gfp_t gfp) { struct sctp_ulpevent *event; struct sctp_assoc_change *sac; struct sk_buff *skb; /* If the lower layer passed in the chunk, it will be * an ABORT, so we need to include it in the sac_info. */ if (chunk) { /* Copy the chunk data to a new skb and reserve enough * head room to use as notification. */ skb = skb_copy_expand(chunk->skb, sizeof(struct sctp_assoc_change), 0, gfp); if (!skb) goto fail; /* Embed the event fields inside the cloned skb. */ event = sctp_skb2event(skb); sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize); /* Include the notification structure */ sac = (struct sctp_assoc_change *) skb_push(skb, sizeof(struct sctp_assoc_change)); /* Trim the buffer to the right length. */ skb_trim(skb, sizeof(struct sctp_assoc_change) + ntohs(chunk->chunk_hdr->length) - sizeof(sctp_chunkhdr_t)); } else { event = sctp_ulpevent_new(sizeof(struct sctp_assoc_change), MSG_NOTIFICATION, gfp); if (!event) goto fail; skb = sctp_event2skb(event); sac = (struct sctp_assoc_change *) skb_put(skb, sizeof(struct sctp_assoc_change)); } /* Socket Extensions for SCTP * 5.3.1.1 SCTP_ASSOC_CHANGE * * sac_type: * It should be SCTP_ASSOC_CHANGE. */ sac->sac_type = SCTP_ASSOC_CHANGE; /* Socket Extensions for SCTP * 5.3.1.1 SCTP_ASSOC_CHANGE * * sac_state: 32 bits (signed integer) * This field holds one of a number of values that communicate the * event that happened to the association. */ sac->sac_state = state; /* Socket Extensions for SCTP * 5.3.1.1 SCTP_ASSOC_CHANGE * * sac_flags: 16 bits (unsigned integer) * Currently unused. */ sac->sac_flags = 0; /* Socket Extensions for SCTP * 5.3.1.1 SCTP_ASSOC_CHANGE * * sac_length: sizeof (__u32) * This field is the total length of the notification data, including * the notification header. */ sac->sac_length = skb->len; /* Socket Extensions for SCTP * 5.3.1.1 SCTP_ASSOC_CHANGE * * sac_error: 32 bits (signed integer) * * If the state was reached due to a error condition (e.g. * COMMUNICATION_LOST) any relevant error information is available in * this field. This corresponds to the protocol error codes defined in * [SCTP]. */ sac->sac_error = error; /* Socket Extensions for SCTP * 5.3.1.1 SCTP_ASSOC_CHANGE * * sac_outbound_streams: 16 bits (unsigned integer) * sac_inbound_streams: 16 bits (unsigned integer) * * The maximum number of streams allowed in each direction are * available in sac_outbound_streams and sac_inbound streams. */ sac->sac_outbound_streams = outbound; sac->sac_inbound_streams = inbound; /* Socket Extensions for SCTP * 5.3.1.1 SCTP_ASSOC_CHANGE * * sac_assoc_id: sizeof (sctp_assoc_t) * * The association id field, holds the identifier for the association. * All notifications for a given association have the same association * identifier. For TCP style socket, this field is ignored. */ sctp_ulpevent_set_owner(event, asoc); sac->sac_assoc_id = sctp_assoc2id(asoc); return event; fail: return NULL; } /* Create and initialize an SCTP_PEER_ADDR_CHANGE event. * * Socket Extensions for SCTP - draft-01 * 5.3.1.2 SCTP_PEER_ADDR_CHANGE * * When a destination address on a multi-homed peer encounters a change * an interface details event is sent. */ struct sctp_ulpevent *sctp_ulpevent_make_peer_addr_change( const struct sctp_association *asoc, const struct sockaddr_storage *aaddr, int flags, int state, int error, gfp_t gfp) { struct sctp_ulpevent *event; struct sctp_paddr_change *spc; struct sk_buff *skb; event = sctp_ulpevent_new(sizeof(struct sctp_paddr_change), MSG_NOTIFICATION, gfp); if (!event) goto fail; skb = sctp_event2skb(event); spc = (struct sctp_paddr_change *) skb_put(skb, sizeof(struct sctp_paddr_change)); /* Sockets API Extensions for SCTP * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE * * spc_type: * * It should be SCTP_PEER_ADDR_CHANGE. */ spc->spc_type = SCTP_PEER_ADDR_CHANGE; /* Sockets API Extensions for SCTP * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE * * spc_length: sizeof (__u32) * * This field is the total length of the notification data, including * the notification header. */ spc->spc_length = sizeof(struct sctp_paddr_change); /* Sockets API Extensions for SCTP * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE * * spc_flags: 16 bits (unsigned integer) * Currently unused. */ spc->spc_flags = 0; /* Sockets API Extensions for SCTP * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE * * spc_state: 32 bits (signed integer) * * This field holds one of a number of values that communicate the * event that happened to the address. */ spc->spc_state = state; /* Sockets API Extensions for SCTP * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE * * spc_error: 32 bits (signed integer) * * If the state was reached due to any error condition (e.g. * ADDRESS_UNREACHABLE) any relevant error information is available in * this field. */ spc->spc_error = error; /* Socket Extensions for SCTP * 5.3.1.1 SCTP_ASSOC_CHANGE * * spc_assoc_id: sizeof (sctp_assoc_t) * * The association id field, holds the identifier for the association. * All notifications for a given association have the same association * identifier. For TCP style socket, this field is ignored. */ sctp_ulpevent_set_owner(event, asoc); spc->spc_assoc_id = sctp_assoc2id(asoc); /* Sockets API Extensions for SCTP * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE * * spc_aaddr: sizeof (struct sockaddr_storage) * * The affected address field, holds the remote peer's address that is * encountering the change of state. */ memcpy(&spc->spc_aaddr, aaddr, sizeof(struct sockaddr_storage)); /* Map ipv4 address into v4-mapped-on-v6 address. */ sctp_get_pf_specific(asoc->base.sk->sk_family)->addr_to_user( sctp_sk(asoc->base.sk), (union sctp_addr *)&spc->spc_aaddr); return event; fail: return NULL; } /* Create and initialize an SCTP_REMOTE_ERROR notification. * * Note: This assumes that the chunk->skb->data already points to the * operation error payload. * * Socket Extensions for SCTP - draft-01 * 5.3.1.3 SCTP_REMOTE_ERROR * * A remote peer may send an Operational Error message to its peer. * This message indicates a variety of error conditions on an * association. The entire error TLV as it appears on the wire is * included in a SCTP_REMOTE_ERROR event. Please refer to the SCTP * specification [SCTP] and any extensions for a list of possible * error formats. */ struct sctp_ulpevent * sctp_ulpevent_make_remote_error(const struct sctp_association *asoc, struct sctp_chunk *chunk, __u16 flags, gfp_t gfp) { struct sctp_ulpevent *event; struct sctp_remote_error *sre; struct sk_buff *skb; sctp_errhdr_t *ch; __be16 cause; int elen; ch = (sctp_errhdr_t *)(chunk->skb->data); cause = ch->cause; elen = SCTP_PAD4(ntohs(ch->length)) - sizeof(sctp_errhdr_t); /* Pull off the ERROR header. */ skb_pull(chunk->skb, sizeof(sctp_errhdr_t)); /* Copy the skb to a new skb with room for us to prepend * notification with. */ skb = skb_copy_expand(chunk->skb, sizeof(*sre), 0, gfp); /* Pull off the rest of the cause TLV from the chunk. */ skb_pull(chunk->skb, elen); if (!skb) goto fail; /* Embed the event fields inside the cloned skb. */ event = sctp_skb2event(skb); sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize); sre = (struct sctp_remote_error *) skb_push(skb, sizeof(*sre)); /* Trim the buffer to the right length. */ skb_trim(skb, sizeof(*sre) + elen); /* RFC6458, Section 6.1.3. SCTP_REMOTE_ERROR */ memset(sre, 0, sizeof(*sre)); sre->sre_type = SCTP_REMOTE_ERROR; sre->sre_flags = 0; sre->sre_length = skb->len; sre->sre_error = cause; sctp_ulpevent_set_owner(event, asoc); sre->sre_assoc_id = sctp_assoc2id(asoc); return event; fail: return NULL; } /* Create and initialize a SCTP_SEND_FAILED notification. * * Socket Extensions for SCTP - draft-01 * 5.3.1.4 SCTP_SEND_FAILED */ struct sctp_ulpevent *sctp_ulpevent_make_send_failed( const struct sctp_association *asoc, struct sctp_chunk *chunk, __u16 flags, __u32 error, gfp_t gfp) { struct sctp_ulpevent *event; struct sctp_send_failed *ssf; struct sk_buff *skb; /* Pull off any padding. */ int len = ntohs(chunk->chunk_hdr->length); /* Make skb with more room so we can prepend notification. */ skb = skb_copy_expand(chunk->skb, sizeof(struct sctp_send_failed), /* headroom */ 0, /* tailroom */ gfp); if (!skb) goto fail; /* Pull off the common chunk header and DATA header. */ skb_pull(skb, sizeof(struct sctp_data_chunk)); len -= sizeof(struct sctp_data_chunk); /* Embed the event fields inside the cloned skb. */ event = sctp_skb2event(skb); sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize); ssf = (struct sctp_send_failed *) skb_push(skb, sizeof(struct sctp_send_failed)); /* Socket Extensions for SCTP * 5.3.1.4 SCTP_SEND_FAILED * * ssf_type: * It should be SCTP_SEND_FAILED. */ ssf->ssf_type = SCTP_SEND_FAILED; /* Socket Extensions for SCTP * 5.3.1.4 SCTP_SEND_FAILED * * ssf_flags: 16 bits (unsigned integer) * The flag value will take one of the following values * * SCTP_DATA_UNSENT - Indicates that the data was never put on * the wire. * * SCTP_DATA_SENT - Indicates that the data was put on the wire. * Note that this does not necessarily mean that the * data was (or was not) successfully delivered. */ ssf->ssf_flags = flags; /* Socket Extensions for SCTP * 5.3.1.4 SCTP_SEND_FAILED * * ssf_length: sizeof (__u32) * This field is the total length of the notification data, including * the notification header. */ ssf->ssf_length = sizeof(struct sctp_send_failed) + len; skb_trim(skb, ssf->ssf_length); /* Socket Extensions for SCTP * 5.3.1.4 SCTP_SEND_FAILED * * ssf_error: 16 bits (unsigned integer) * This value represents the reason why the send failed, and if set, * will be a SCTP protocol error code as defined in [SCTP] section * 3.3.10. */ ssf->ssf_error = error; /* Socket Extensions for SCTP * 5.3.1.4 SCTP_SEND_FAILED * * ssf_info: sizeof (struct sctp_sndrcvinfo) * The original send information associated with the undelivered * message. */ memcpy(&ssf->ssf_info, &chunk->sinfo, sizeof(struct sctp_sndrcvinfo)); /* Per TSVWG discussion with Randy. Allow the application to * reassemble a fragmented message. */ ssf->ssf_info.sinfo_flags = chunk->chunk_hdr->flags; /* Socket Extensions for SCTP * 5.3.1.4 SCTP_SEND_FAILED * * ssf_assoc_id: sizeof (sctp_assoc_t) * The association id field, sf_assoc_id, holds the identifier for the * association. All notifications for a given association have the * same association identifier. For TCP style socket, this field is * ignored. */ sctp_ulpevent_set_owner(event, asoc); ssf->ssf_assoc_id = sctp_assoc2id(asoc); return event; fail: return NULL; } /* Create and initialize a SCTP_SHUTDOWN_EVENT notification. * * Socket Extensions for SCTP - draft-01 * 5.3.1.5 SCTP_SHUTDOWN_EVENT */ struct sctp_ulpevent *sctp_ulpevent_make_shutdown_event( const struct sctp_association *asoc, __u16 flags, gfp_t gfp) { struct sctp_ulpevent *event; struct sctp_shutdown_event *sse; struct sk_buff *skb; event = sctp_ulpevent_new(sizeof(struct sctp_shutdown_event), MSG_NOTIFICATION, gfp); if (!event) goto fail; skb = sctp_event2skb(event); sse = (struct sctp_shutdown_event *) skb_put(skb, sizeof(struct sctp_shutdown_event)); /* Socket Extensions for SCTP * 5.3.1.5 SCTP_SHUTDOWN_EVENT * * sse_type * It should be SCTP_SHUTDOWN_EVENT */ sse->sse_type = SCTP_SHUTDOWN_EVENT; /* Socket Extensions for SCTP * 5.3.1.5 SCTP_SHUTDOWN_EVENT * * sse_flags: 16 bits (unsigned integer) * Currently unused. */ sse->sse_flags = 0; /* Socket Extensions for SCTP * 5.3.1.5 SCTP_SHUTDOWN_EVENT * * sse_length: sizeof (__u32) * This field is the total length of the notification data, including * the notification header. */ sse->sse_length = sizeof(struct sctp_shutdown_event); /* Socket Extensions for SCTP * 5.3.1.5 SCTP_SHUTDOWN_EVENT * * sse_assoc_id: sizeof (sctp_assoc_t) * The association id field, holds the identifier for the association. * All notifications for a given association have the same association * identifier. For TCP style socket, this field is ignored. */ sctp_ulpevent_set_owner(event, asoc); sse->sse_assoc_id = sctp_assoc2id(asoc); return event; fail: return NULL; } /* Create and initialize a SCTP_ADAPTATION_INDICATION notification. * * Socket Extensions for SCTP * 5.3.1.6 SCTP_ADAPTATION_INDICATION */ struct sctp_ulpevent *sctp_ulpevent_make_adaptation_indication( const struct sctp_association *asoc, gfp_t gfp) { struct sctp_ulpevent *event; struct sctp_adaptation_event *sai; struct sk_buff *skb; event = sctp_ulpevent_new(sizeof(struct sctp_adaptation_event), MSG_NOTIFICATION, gfp); if (!event) goto fail; skb = sctp_event2skb(event); sai = (struct sctp_adaptation_event *) skb_put(skb, sizeof(struct sctp_adaptation_event)); sai->sai_type = SCTP_ADAPTATION_INDICATION; sai->sai_flags = 0; sai->sai_length = sizeof(struct sctp_adaptation_event); sai->sai_adaptation_ind = asoc->peer.adaptation_ind; sctp_ulpevent_set_owner(event, asoc); sai->sai_assoc_id = sctp_assoc2id(asoc); return event; fail: return NULL; } /* A message has been received. Package this message as a notification * to pass it to the upper layers. Go ahead and calculate the sndrcvinfo * even if filtered out later. * * Socket Extensions for SCTP * 5.2.2 SCTP Header Information Structure (SCTP_SNDRCV) */ struct sctp_ulpevent *sctp_ulpevent_make_rcvmsg(struct sctp_association *asoc, struct sctp_chunk *chunk, gfp_t gfp) { struct sctp_ulpevent *event = NULL; struct sk_buff *skb; size_t padding, len; int rx_count; /* * check to see if we need to make space for this * new skb, expand the rcvbuffer if needed, or drop * the frame */ if (asoc->ep->rcvbuf_policy) rx_count = atomic_read(&asoc->rmem_alloc); else rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc); if (rx_count >= asoc->base.sk->sk_rcvbuf) { if ((asoc->base.sk->sk_userlocks & SOCK_RCVBUF_LOCK) || (!sk_rmem_schedule(asoc->base.sk, chunk->skb, chunk->skb->truesize))) goto fail; } /* Clone the original skb, sharing the data. */ skb = skb_clone(chunk->skb, gfp); if (!skb) goto fail; /* Now that all memory allocations for this chunk succeeded, we * can mark it as received so the tsn_map is updated correctly. */ if (sctp_tsnmap_mark(&asoc->peer.tsn_map, ntohl(chunk->subh.data_hdr->tsn), chunk->transport)) goto fail_mark; /* First calculate the padding, so we don't inadvertently * pass up the wrong length to the user. * * RFC 2960 - Section 3.2 Chunk Field Descriptions * * The total length of a chunk(including Type, Length and Value fields) * MUST be a multiple of 4 bytes. If the length of the chunk is not a * multiple of 4 bytes, the sender MUST pad the chunk with all zero * bytes and this padding is not included in the chunk length field. * The sender should never pad with more than 3 bytes. The receiver * MUST ignore the padding bytes. */ len = ntohs(chunk->chunk_hdr->length); padding = SCTP_PAD4(len) - len; /* Fixup cloned skb with just this chunks data. */ skb_trim(skb, chunk->chunk_end - padding - skb->data); /* Embed the event fields inside the cloned skb. */ event = sctp_skb2event(skb); /* Initialize event with flags 0 and correct length * Since this is a clone of the original skb, only account for * the data of this chunk as other chunks will be accounted separately. */ sctp_ulpevent_init(event, 0, skb->len + sizeof(struct sk_buff)); /* And hold the chunk as we need it for getting the IP headers * later in recvmsg */ sctp_chunk_hold(chunk); event->chunk = chunk; sctp_ulpevent_receive_data(event, asoc); event->stream = ntohs(chunk->subh.data_hdr->stream); event->ssn = ntohs(chunk->subh.data_hdr->ssn); event->ppid = chunk->subh.data_hdr->ppid; if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) { event->flags |= SCTP_UNORDERED; event->cumtsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map); } event->tsn = ntohl(chunk->subh.data_hdr->tsn); event->msg_flags |= chunk->chunk_hdr->flags; return event; fail_mark: sctp_chunk_put(chunk); kfree_skb(skb); fail: return NULL; } /* Create a partial delivery related event. * * 5.3.1.7 SCTP_PARTIAL_DELIVERY_EVENT * * When a receiver is engaged in a partial delivery of a * message this notification will be used to indicate * various events. */ struct sctp_ulpevent *sctp_ulpevent_make_pdapi( const struct sctp_association *asoc, __u32 indication, gfp_t gfp) { struct sctp_ulpevent *event; struct sctp_pdapi_event *pd; struct sk_buff *skb; event = sctp_ulpevent_new(sizeof(struct sctp_pdapi_event), MSG_NOTIFICATION, gfp); if (!event) goto fail; skb = sctp_event2skb(event); pd = (struct sctp_pdapi_event *) skb_put(skb, sizeof(struct sctp_pdapi_event)); /* pdapi_type * It should be SCTP_PARTIAL_DELIVERY_EVENT * * pdapi_flags: 16 bits (unsigned integer) * Currently unused. */ pd->pdapi_type = SCTP_PARTIAL_DELIVERY_EVENT; pd->pdapi_flags = 0; /* pdapi_length: 32 bits (unsigned integer) * * This field is the total length of the notification data, including * the notification header. It will generally be sizeof (struct * sctp_pdapi_event). */ pd->pdapi_length = sizeof(struct sctp_pdapi_event); /* pdapi_indication: 32 bits (unsigned integer) * * This field holds the indication being sent to the application. */ pd->pdapi_indication = indication; /* pdapi_assoc_id: sizeof (sctp_assoc_t) * * The association id field, holds the identifier for the association. */ sctp_ulpevent_set_owner(event, asoc); pd->pdapi_assoc_id = sctp_assoc2id(asoc); return event; fail: return NULL; } struct sctp_ulpevent *sctp_ulpevent_make_authkey( const struct sctp_association *asoc, __u16 key_id, __u32 indication, gfp_t gfp) { struct sctp_ulpevent *event; struct sctp_authkey_event *ak; struct sk_buff *skb; event = sctp_ulpevent_new(sizeof(struct sctp_authkey_event), MSG_NOTIFICATION, gfp); if (!event) goto fail; skb = sctp_event2skb(event); ak = (struct sctp_authkey_event *) skb_put(skb, sizeof(struct sctp_authkey_event)); ak->auth_type = SCTP_AUTHENTICATION_EVENT; ak->auth_flags = 0; ak->auth_length = sizeof(struct sctp_authkey_event); ak->auth_keynumber = key_id; ak->auth_altkeynumber = 0; ak->auth_indication = indication; /* * The association id field, holds the identifier for the association. */ sctp_ulpevent_set_owner(event, asoc); ak->auth_assoc_id = sctp_assoc2id(asoc); return event; fail: return NULL; } /* * Socket Extensions for SCTP * 6.3.10. SCTP_SENDER_DRY_EVENT */ struct sctp_ulpevent *sctp_ulpevent_make_sender_dry_event( const struct sctp_association *asoc, gfp_t gfp) { struct sctp_ulpevent *event; struct sctp_sender_dry_event *sdry; struct sk_buff *skb; event = sctp_ulpevent_new(sizeof(struct sctp_sender_dry_event), MSG_NOTIFICATION, gfp); if (!event) return NULL; skb = sctp_event2skb(event); sdry = (struct sctp_sender_dry_event *) skb_put(skb, sizeof(struct sctp_sender_dry_event)); sdry->sender_dry_type = SCTP_SENDER_DRY_EVENT; sdry->sender_dry_flags = 0; sdry->sender_dry_length = sizeof(struct sctp_sender_dry_event); sctp_ulpevent_set_owner(event, asoc); sdry->sender_dry_assoc_id = sctp_assoc2id(asoc); return event; } struct sctp_ulpevent *sctp_ulpevent_make_stream_reset_event( const struct sctp_association *asoc, __u16 flags, __u16 stream_num, __u16 *stream_list, gfp_t gfp) { struct sctp_stream_reset_event *sreset; struct sctp_ulpevent *event; struct sk_buff *skb; int length, i; length = sizeof(struct sctp_stream_reset_event) + 2 * stream_num; event = sctp_ulpevent_new(length, MSG_NOTIFICATION, gfp); if (!event) return NULL; skb = sctp_event2skb(event); sreset = (struct sctp_stream_reset_event *)skb_put(skb, length); sreset->strreset_type = SCTP_STREAM_RESET_EVENT; sreset->strreset_flags = flags; sreset->strreset_length = length; sctp_ulpevent_set_owner(event, asoc); sreset->strreset_assoc_id = sctp_assoc2id(asoc); for (i = 0; i < stream_num; i++) sreset->strreset_stream_list[i] = ntohs(stream_list[i]); return event; } /* Return the notification type, assuming this is a notification * event. */ __u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event) { union sctp_notification *notification; struct sk_buff *skb; skb = sctp_event2skb(event); notification = (union sctp_notification *) skb->data; return notification->sn_header.sn_type; } /* RFC6458, Section 5.3.2. SCTP Header Information Structure * (SCTP_SNDRCV, DEPRECATED) */ void sctp_ulpevent_read_sndrcvinfo(const struct sctp_ulpevent *event, struct msghdr *msghdr) { struct sctp_sndrcvinfo sinfo; if (sctp_ulpevent_is_notification(event)) return; memset(&sinfo, 0, sizeof(sinfo)); sinfo.sinfo_stream = event->stream; sinfo.sinfo_ssn = event->ssn; sinfo.sinfo_ppid = event->ppid; sinfo.sinfo_flags = event->flags; sinfo.sinfo_tsn = event->tsn; sinfo.sinfo_cumtsn = event->cumtsn; sinfo.sinfo_assoc_id = sctp_assoc2id(event->asoc); /* Context value that is set via SCTP_CONTEXT socket option. */ sinfo.sinfo_context = event->asoc->default_rcv_context; /* These fields are not used while receiving. */ sinfo.sinfo_timetolive = 0; put_cmsg(msghdr, IPPROTO_SCTP, SCTP_SNDRCV, sizeof(sinfo), &sinfo); } /* RFC6458, Section 5.3.5 SCTP Receive Information Structure * (SCTP_SNDRCV) */ void sctp_ulpevent_read_rcvinfo(const struct sctp_ulpevent *event, struct msghdr *msghdr) { struct sctp_rcvinfo rinfo; if (sctp_ulpevent_is_notification(event)) return; memset(&rinfo, 0, sizeof(struct sctp_rcvinfo)); rinfo.rcv_sid = event->stream; rinfo.rcv_ssn = event->ssn; rinfo.rcv_ppid = event->ppid; rinfo.rcv_flags = event->flags; rinfo.rcv_tsn = event->tsn; rinfo.rcv_cumtsn = event->cumtsn; rinfo.rcv_assoc_id = sctp_assoc2id(event->asoc); rinfo.rcv_context = event->asoc->default_rcv_context; put_cmsg(msghdr, IPPROTO_SCTP, SCTP_RCVINFO, sizeof(rinfo), &rinfo); } /* RFC6458, Section 5.3.6. SCTP Next Receive Information Structure * (SCTP_NXTINFO) */ static void __sctp_ulpevent_read_nxtinfo(const struct sctp_ulpevent *event, struct msghdr *msghdr, const struct sk_buff *skb) { struct sctp_nxtinfo nxtinfo; memset(&nxtinfo, 0, sizeof(nxtinfo)); nxtinfo.nxt_sid = event->stream; nxtinfo.nxt_ppid = event->ppid; nxtinfo.nxt_flags = event->flags; if (sctp_ulpevent_is_notification(event)) nxtinfo.nxt_flags |= SCTP_NOTIFICATION; nxtinfo.nxt_length = skb->len; nxtinfo.nxt_assoc_id = sctp_assoc2id(event->asoc); put_cmsg(msghdr, IPPROTO_SCTP, SCTP_NXTINFO, sizeof(nxtinfo), &nxtinfo); } void sctp_ulpevent_read_nxtinfo(const struct sctp_ulpevent *event, struct msghdr *msghdr, struct sock *sk) { struct sk_buff *skb; int err; skb = sctp_skb_recv_datagram(sk, MSG_PEEK, 1, &err); if (skb != NULL) { __sctp_ulpevent_read_nxtinfo(sctp_skb2event(skb), msghdr, skb); /* Just release refcount here. */ kfree_skb(skb); } } /* Do accounting for bytes received and hold a reference to the association * for each skb. */ static void sctp_ulpevent_receive_data(struct sctp_ulpevent *event, struct sctp_association *asoc) { struct sk_buff *skb, *frag; skb = sctp_event2skb(event); /* Set the owner and charge rwnd for bytes received. */ sctp_ulpevent_set_owner(event, asoc); sctp_assoc_rwnd_decrease(asoc, skb_headlen(skb)); if (!skb->data_len) return; /* Note: Not clearing the entire event struct as this is just a * fragment of the real event. However, we still need to do rwnd * accounting. * In general, the skb passed from IP can have only 1 level of * fragments. But we allow multiple levels of fragments. */ skb_walk_frags(skb, frag) sctp_ulpevent_receive_data(sctp_skb2event(frag), asoc); } /* Do accounting for bytes just read by user and release the references to * the association. */ static void sctp_ulpevent_release_data(struct sctp_ulpevent *event) { struct sk_buff *skb, *frag; unsigned int len; /* Current stack structures assume that the rcv buffer is * per socket. For UDP style sockets this is not true as * multiple associations may be on a single UDP-style socket. * Use the local private area of the skb to track the owning * association. */ skb = sctp_event2skb(event); len = skb->len; if (!skb->data_len) goto done; /* Don't forget the fragments. */ skb_walk_frags(skb, frag) { /* NOTE: skb_shinfos are recursive. Although IP returns * skb's with only 1 level of fragments, SCTP reassembly can * increase the levels. */ sctp_ulpevent_release_frag_data(sctp_skb2event(frag)); } done: sctp_assoc_rwnd_increase(event->asoc, len); sctp_chunk_put(event->chunk); sctp_ulpevent_release_owner(event); } static void sctp_ulpevent_release_frag_data(struct sctp_ulpevent *event) { struct sk_buff *skb, *frag; skb = sctp_event2skb(event); if (!skb->data_len) goto done; /* Don't forget the fragments. */ skb_walk_frags(skb, frag) { /* NOTE: skb_shinfos are recursive. Although IP returns * skb's with only 1 level of fragments, SCTP reassembly can * increase the levels. */ sctp_ulpevent_release_frag_data(sctp_skb2event(frag)); } done: sctp_chunk_put(event->chunk); sctp_ulpevent_release_owner(event); } /* Free a ulpevent that has an owner. It includes releasing the reference * to the owner, updating the rwnd in case of a DATA event and freeing the * skb. */ void sctp_ulpevent_free(struct sctp_ulpevent *event) { if (sctp_ulpevent_is_notification(event)) sctp_ulpevent_release_owner(event); else sctp_ulpevent_release_data(event); kfree_skb(sctp_event2skb(event)); } /* Purge the skb lists holding ulpevents. */ unsigned int sctp_queue_purge_ulpevents(struct sk_buff_head *list) { struct sk_buff *skb; unsigned int data_unread = 0; while ((skb = skb_dequeue(list)) != NULL) { struct sctp_ulpevent *event = sctp_skb2event(skb); if (!sctp_ulpevent_is_notification(event)) data_unread += skb->len; sctp_ulpevent_free(event); } return data_unread; }