/*-

 * SPDX-License-Identifier: BSD-3-Clause

 *

 * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved.

 * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.

 * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are met:

 *

 * a) Redistributions of source code must retain the above copyright notice,

 *    this list of conditions and the following disclaimer.

 *

 * b) Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in

 *    the documentation and/or other materials provided with the distribution.

 *

 * c) Neither the name of Cisco Systems, Inc. nor the names of its

 *    contributors may be used to endorse or promote products derived

 *    from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,

 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE

 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF

 * THE POSSIBILITY OF SUCH DAMAGE.

 */

#include <netinet/sctp_os.h>

#include <netinet/sctp_pcb.h>

#include <netinet/sctputil.h>

#include <netinet/sctp_var.h>

#include <netinet/sctp_var.h>

#include <netinet/sctp_sysctl.h>

#include <netinet/sctp.h>

#include <netinet/sctp_uio.h>

#include <netinet/sctp_peeloff.h>

#include <netinet/sctputil.h>

#include <netinet/sctp_auth.h>

int

sctp_can_peel_off(struct socket *head, sctp_assoc_t assoc_id)

{

  struct sctp_inpcb *inp;

  struct sctp_tcb *stcb;

  uint32_t state;

  if (head == NULL) {

    SCTP_LTRACE_ERR_RET(NULL, NULL, NULL, SCTP_FROM_SCTP_PEELOFF, EBADF);

    return (EBADF);

  }

  inp = (struct sctp_inpcb *)head->so_pcb;

  if (inp == NULL) {

    SCTP_LTRACE_ERR_RET(NULL, NULL, NULL, SCTP_FROM_SCTP_PEELOFF, EFAULT);

    return (EFAULT);

  }

  if ((inp->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) ||

      (inp->sctp_flags & SCTP_PCB_FLAGS_IN_TCPPOOL)) {

    SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP_PEELOFF, EOPNOTSUPP);

    return (EOPNOTSUPP);

  }

  stcb = sctp_findassociation_ep_asocid(inp, assoc_id, 1);

  if (stcb == NULL) {

    SCTP_LTRACE_ERR_RET(inp, stcb, NULL, SCTP_FROM_SCTP_PEELOFF, ENOENT);

    return (ENOENT);

  }

  state = SCTP_GET_STATE(stcb);

  if ((state == SCTP_STATE_EMPTY) ||

      (state == SCTP_STATE_INUSE)) {

    SCTP_TCB_UNLOCK(stcb);

    SCTP_LTRACE_ERR_RET(inp, stcb, NULL, SCTP_FROM_SCTP_PEELOFF, ENOTCONN);

    return (ENOTCONN);

  }

  SCTP_TCB_UNLOCK(stcb);

  /* We are clear to peel this one off */

  return (0);

}

int

sctp_do_peeloff(struct socket *head, struct socket *so, sctp_assoc_t assoc_id)

{

  struct sctp_inpcb *inp, *n_inp;

  struct sctp_tcb *stcb;

  uint32_t state;

  inp = (struct sctp_inpcb *)head->so_pcb;

  if (inp == NULL) {

    SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP_PEELOFF, EFAULT);

    return (EFAULT);

  }

  stcb = sctp_findassociation_ep_asocid(inp, assoc_id, 1);

  if (stcb == NULL) {

    SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP_PEELOFF, ENOTCONN);

    return (ENOTCONN);

  }

  state = SCTP_GET_STATE(stcb);

  if ((state == SCTP_STATE_EMPTY) ||

      (state == SCTP_STATE_INUSE)) {

    SCTP_TCB_UNLOCK(stcb);

    SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP_PEELOFF, ENOTCONN);

    return (ENOTCONN);

  }

  n_inp = (struct sctp_inpcb *)so->so_pcb;

  n_inp->sctp_flags = (SCTP_PCB_FLAGS_UDPTYPE |

      SCTP_PCB_FLAGS_CONNECTED |

      SCTP_PCB_FLAGS_IN_TCPPOOL |  /* Turn on Blocking IO */

      (SCTP_PCB_COPY_FLAGS & inp->sctp_flags));

  n_inp->sctp_socket = so;

  n_inp->sctp_features = inp->sctp_features;

  n_inp->sctp_mobility_features = inp->sctp_mobility_features;

  n_inp->sctp_frag_point = inp->sctp_frag_point;

  n_inp->sctp_cmt_on_off = inp->sctp_cmt_on_off;

  n_inp->ecn_supported = inp->ecn_supported;

  n_inp->prsctp_supported = inp->prsctp_supported;

  n_inp->auth_supported = inp->auth_supported;

  n_inp->asconf_supported = inp->asconf_supported;

  n_inp->reconfig_supported = inp->reconfig_supported;

  n_inp->nrsack_supported = inp->nrsack_supported;

  n_inp->pktdrop_supported = inp->pktdrop_supported;

  n_inp->partial_delivery_point = inp->partial_delivery_point;

  n_inp->sctp_context = inp->sctp_context;

  n_inp->max_cwnd = inp->max_cwnd;

  n_inp->local_strreset_support = inp->local_strreset_support;

  /* copy in the authentication parameters from the original endpoint */

  if (n_inp->sctp_ep.local_hmacs)

    sctp_free_hmaclist(n_inp->sctp_ep.local_hmacs);

  n_inp->sctp_ep.local_hmacs =

      sctp_copy_hmaclist(inp->sctp_ep.local_hmacs);

  if (n_inp->sctp_ep.local_auth_chunks)

    sctp_free_chunklist(n_inp->sctp_ep.local_auth_chunks);

  n_inp->sctp_ep.local_auth_chunks =

      sctp_copy_chunklist(inp->sctp_ep.local_auth_chunks);

  (void)sctp_copy_skeylist(&inp->sctp_ep.shared_keys,

      &n_inp->sctp_ep.shared_keys);

#if defined(__Userspace__)

  n_inp->ulp_info = inp->ulp_info;

  n_inp->recv_callback = inp->recv_callback;

  n_inp->send_callback = inp->send_callback;

  n_inp->send_sb_threshold = inp->send_sb_threshold;

#endif

  /*

   * Now we must move it from one hash table to another and get the

   * stcb in the right place.

   */

  sctp_move_pcb_and_assoc(inp, n_inp, stcb);

  atomic_add_int(&stcb->asoc.refcnt, 1);

  SCTP_TCB_UNLOCK(stcb);

#if defined(__FreeBSD__) && !defined(__Userspace__)

  sctp_pull_off_control_to_new_inp(inp, n_inp, stcb, SBL_WAIT);

#else

  sctp_pull_off_control_to_new_inp(inp, n_inp, stcb, M_WAITOK);

#endif

  atomic_subtract_int(&stcb->asoc.refcnt, 1);

  return (0);

}

#if defined(HAVE_SCTP_PEELOFF_SOCKOPT)

struct socket *

sctp_get_peeloff(struct socket *head, sctp_assoc_t assoc_id, int *error)

{

  struct socket *newso;

  struct sctp_inpcb *inp, *n_inp;

  struct sctp_tcb *stcb;

  SCTPDBG(SCTP_DEBUG_PEEL1, "SCTP peel-off called\n");

  inp = (struct sctp_inpcb *)head->so_pcb;

  if (inp == NULL) {

    SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP_PEELOFF, EFAULT);

    *error = EFAULT;

    return (NULL);

  }

  stcb = sctp_findassociation_ep_asocid(inp, assoc_id, 1);

  if (stcb == NULL) {

    SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP_PEELOFF, ENOTCONN);

    *error = ENOTCONN;

    return (NULL);

  }

  atomic_add_int(&stcb->asoc.refcnt, 1);

  SCTP_TCB_UNLOCK(stcb);

#if defined(__FreeBSD__) && !defined(__Userspace__)

  CURVNET_SET(head->so_vnet);

#endif

  newso = sonewconn(head, SS_ISCONNECTED

#if defined(__APPLE__) && !defined(__Userspace__)

      , NULL

#endif

    );

#if defined(__FreeBSD__) && !defined(__Userspace__)

  CURVNET_RESTORE();

#endif

  if (newso == NULL) {

    SCTPDBG(SCTP_DEBUG_PEEL1, "sctp_peeloff:sonewconn failed\n");

    SCTP_LTRACE_ERR_RET(NULL, stcb, NULL, SCTP_FROM_SCTP_PEELOFF, ENOMEM);

    *error = ENOMEM;

    atomic_subtract_int(&stcb->asoc.refcnt, 1);

    return (NULL);

  }

#if defined(__APPLE__) && !defined(__Userspace__)

    else {

    SCTP_SOCKET_LOCK(newso, 1);

  }

#endif

  SCTP_TCB_LOCK(stcb);

  atomic_subtract_int(&stcb->asoc.refcnt, 1);

  n_inp = (struct sctp_inpcb *)newso->so_pcb;

  SOCK_LOCK(head);

  n_inp->sctp_flags = (SCTP_PCB_FLAGS_UDPTYPE |

      SCTP_PCB_FLAGS_CONNECTED |

      SCTP_PCB_FLAGS_IN_TCPPOOL | /* Turn on Blocking IO */

      (SCTP_PCB_COPY_FLAGS & inp->sctp_flags));

  n_inp->sctp_features = inp->sctp_features;

  n_inp->sctp_frag_point = inp->sctp_frag_point;

  n_inp->sctp_cmt_on_off = inp->sctp_cmt_on_off;

  n_inp->ecn_supported = inp->ecn_supported;

  n_inp->prsctp_supported = inp->prsctp_supported;

  n_inp->auth_supported = inp->auth_supported;

  n_inp->asconf_supported = inp->asconf_supported;

  n_inp->reconfig_supported = inp->reconfig_supported;

  n_inp->nrsack_supported = inp->nrsack_supported;

  n_inp->pktdrop_supported = inp->pktdrop_supported;

  n_inp->partial_delivery_point = inp->partial_delivery_point;

  n_inp->sctp_context = inp->sctp_context;

  n_inp->max_cwnd = inp->max_cwnd;

  n_inp->local_strreset_support = inp->local_strreset_support;

  n_inp->inp_starting_point_for_iterator = NULL;

#if defined(__Userspace__)

  n_inp->ulp_info = inp->ulp_info;

  n_inp->recv_callback = inp->recv_callback;

  n_inp->send_callback = inp->send_callback;

  n_inp->send_sb_threshold = inp->send_sb_threshold;

#endif

  /* copy in the authentication parameters from the original endpoint */

  if (n_inp->sctp_ep.local_hmacs)

    sctp_free_hmaclist(n_inp->sctp_ep.local_hmacs);

  n_inp->sctp_ep.local_hmacs =

      sctp_copy_hmaclist(inp->sctp_ep.local_hmacs);

  if (n_inp->sctp_ep.local_auth_chunks)

    sctp_free_chunklist(n_inp->sctp_ep.local_auth_chunks);

  n_inp->sctp_ep.local_auth_chunks =

      sctp_copy_chunklist(inp->sctp_ep.local_auth_chunks);

  (void)sctp_copy_skeylist(&inp->sctp_ep.shared_keys,

      &n_inp->sctp_ep.shared_keys);

  n_inp->sctp_socket = newso;

  if (sctp_is_feature_on(inp, SCTP_PCB_FLAGS_AUTOCLOSE)) {

    sctp_feature_off(n_inp, SCTP_PCB_FLAGS_AUTOCLOSE);

    n_inp->sctp_ep.auto_close_time = 0;

    sctp_timer_stop(SCTP_TIMER_TYPE_AUTOCLOSE, n_inp, stcb, NULL,

        SCTP_FROM_SCTP_PEELOFF + SCTP_LOC_1);

  }

  /* Turn off any non-blocking semantic. */

  SOCK_LOCK(newso);

  SCTP_CLEAR_SO_NBIO(newso);

  newso->so_state |= SS_ISCONNECTED;

  SOCK_UNLOCK(newso);

  /* We remove it right away */

#ifdef SCTP_LOCK_LOGGING

  if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LOCK_LOGGING_ENABLE) {

    sctp_log_lock(inp, (struct sctp_tcb *)NULL, SCTP_LOG_LOCK_SOCK);

  }

#endif

  TAILQ_REMOVE(&head->so_comp, newso, so_list);

  head->so_qlen--;

  SOCK_UNLOCK(head);

  /*

   * Now we must move it from one hash table to another and get the

   * stcb in the right place.

   */

  sctp_move_pcb_and_assoc(inp, n_inp, stcb);

  atomic_add_int(&stcb->asoc.refcnt, 1);

  SCTP_TCB_UNLOCK(stcb);

  /*

   * And now the final hack. We move data in the pending side i.e.

   * head to the new socket buffer. Let the GRUBBING begin :-0

   */

#if defined(__FreeBSD__) && !defined(__Userspace__)

  sctp_pull_off_control_to_new_inp(inp, n_inp, stcb, SBL_WAIT);

#else

  sctp_pull_off_control_to_new_inp(inp, n_inp, stcb, M_WAITOK);

#endif

  atomic_subtract_int(&stcb->asoc.refcnt, 1);

  return (newso);

}

#endif