/*-
 * Copyright (c) 1982, 1986, 1989, 1990, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. Neither the name of the University 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 REGENTS 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 REGENTS 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 "opt_capsicum.h"
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_sctp.h"
#include "opt_ktrace.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/capsicum.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/sysproto.h>
#include <sys/malloc.h>
#include <sys/filedesc.h>
#include <sys/event.h>
#include <sys/proc.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/filio.h>
#include <sys/jail.h>
#include <sys/mount.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/sf_buf.h>
#include <sys/sysent.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/signalvar.h>
#include <sys/syscall.h>
#include <sys/syscallsubr.h>
#include <sys/sysctl.h>
#include <sys/uio.h>
#include <sys/vnode.h>
#ifdef KTRACE
#include <sys/ktrace.h>
#endif
#ifdef COMPAT_FREEBSD32
#include <compat/freebsd32/freebsd32.h>
#include <compat/freebsd32/freebsd32_syscall.h>
#include <compat/freebsd32/freebsd32_util.h>
#endif

#include <net/vnet.h>

#include <security/audit/audit.h>
#include <security/mac/mac_framework.h>

#include <netinet/sctp.h>
#include <netinet/sctp_pcb.h>
#include <netinet/sctp_var.h>
#ifdef INET6
#include <netinet6/sctp6_var.h>
#endif
#include <netinet/sctp_os_bsd.h>
#include <netinet/sctp_peeloff.h>

static struct syscall_helper_data sctp_syscalls[] = {
        SYSCALL_INIT_HELPER_F(sctp_peeloff, SYF_CAPENABLED),
        SYSCALL_INIT_HELPER_F(sctp_generic_sendmsg, SYF_CAPENABLED),
        SYSCALL_INIT_HELPER_F(sctp_generic_sendmsg_iov, SYF_CAPENABLED),
        SYSCALL_INIT_HELPER_F(sctp_generic_recvmsg, SYF_CAPENABLED),
        SYSCALL_INIT_LAST
};

#ifdef COMPAT_FREEBSD32
static struct syscall_helper_data sctp32_syscalls[] = {
        SYSCALL32_INIT_HELPER_COMPAT(sctp_peeloff),
        SYSCALL32_INIT_HELPER_COMPAT(sctp_generic_sendmsg),
        SYSCALL32_INIT_HELPER_COMPAT(sctp_generic_sendmsg_iov),
        SYSCALL32_INIT_HELPER_COMPAT(sctp_generic_recvmsg),
        SYSCALL_INIT_LAST
};
#endif

int
sctp_syscalls_init(void)
{
        int error;

        error = syscall_helper_register(sctp_syscalls, SY_THR_STATIC_KLD);
        if (error != 0)
                return (error);
#ifdef COMPAT_FREEBSD32
        error = syscall32_helper_register(sctp32_syscalls, SY_THR_STATIC_KLD);
        if (error != 0)
                return (error);
#endif
        return (0);
}

#ifdef SCTP
SYSINIT(sctp_syscalls, SI_SUB_SYSCALLS, SI_ORDER_ANY, sctp_syscalls_init, NULL);
#endif

int
sctp_syscalls_uninit(void)
{
        int error;

#ifdef COMPAT_FREEBSD32
        error = syscall32_helper_unregister(sctp32_syscalls);
        if (error != 0)
                return (error);
#endif
        error = syscall_helper_unregister(sctp_syscalls);
        if (error != 0)
                return (error);
        return (0);
}

/*
 * SCTP syscalls.
 */
int
sys_sctp_peeloff(struct thread *td, struct sctp_peeloff_args *uap)
{
        struct file *headfp, *nfp = NULL;
        struct socket *head, *so;
        struct filecaps fcaps;
        cap_rights_t rights;
        u_int fflag;
        int error, fd;

        AUDIT_ARG_FD(uap->sd);
        error = getsock_cap(td, uap->sd,
            cap_rights_init_one(&rights, CAP_PEELOFF), &headfp, &fcaps);
        if (error != 0)
                goto done2;
        fflag = atomic_load_int(&headfp->f_flag);
        head = headfp->f_data;
        if (head->so_proto->pr_protocol != IPPROTO_SCTP) {
                error = EOPNOTSUPP;
                goto done;
        }
        error = sctp_can_peel_off(head, (sctp_assoc_t)uap->name);
        if (error != 0)
                goto done;
        /*
         * At this point we know we do have a assoc to pull
         * we proceed to get the fd setup. This may block
         * but that is ok.
         */

        error = falloc_caps(td, &nfp, &fd, 0, &fcaps);
        if (error != 0)
                goto done;
        td->td_retval[0] = fd;

        CURVNET_SET(head->so_vnet);
        switch (head->so_proto->pr_domain->dom_family) {
#ifdef INET
        case AF_INET:
                so = sopeeloff(head, &sctp_stream_protosw);
                break;
#endif
#ifdef INET6
        case AF_INET6:
                so = sopeeloff(head, &sctp6_stream_protosw);
                break;
#endif
        default:
                error = EOPNOTSUPP;
                goto noconnection;
        }
        if (so == NULL) {
                error = ENOMEM;
                goto noconnection;
        }
        finit(nfp, fflag, DTYPE_SOCKET, so, &socketops);
        error = sctp_do_peeloff(head, so, (sctp_assoc_t)uap->name);
        if (error != 0)
                goto noconnection;
        if (head->so_sigio != NULL)
                fsetown(fgetown(&head->so_sigio), &so->so_sigio);

noconnection:
        /*
         * close the new descriptor, assuming someone hasn't ripped it
         * out from under us.
         */
        if (error != 0)
                fdclose(td, nfp, fd);

        /*
         * Release explicitly held references before returning.
         */
        CURVNET_RESTORE();
done:
        if (nfp != NULL)
                fdrop(nfp, td);
        fdrop(headfp, td);
done2:
        return (error);
}

int
sys_sctp_generic_sendmsg(struct thread *td, struct sctp_generic_sendmsg_args *uap)
{
        struct sctp_sndrcvinfo sinfo, *u_sinfo = NULL;
        struct socket *so;
        struct file *fp = NULL;
        struct sockaddr *to = NULL;
#ifdef KTRACE
        struct uio *ktruio = NULL;
#endif
        struct uio auio;
        struct iovec iov[1];
        cap_rights_t rights;
        int error = 0, len;

        if (uap->sinfo != NULL) {
                error = copyin(uap->sinfo, &sinfo, sizeof (sinfo));
                if (error != 0)
                        return (error);
                u_sinfo = &sinfo;
        }

        cap_rights_init_one(&rights, CAP_SEND);
        if (uap->tolen != 0) {
                error = getsockaddr(&to, uap->to, uap->tolen);
                if (error != 0) {
                        to = NULL;
                        goto sctp_bad2;
                }
                cap_rights_set_one(&rights, CAP_CONNECT);
        }

        AUDIT_ARG_FD(uap->sd);
        error = getsock(td, uap->sd, &rights, &fp);
        if (error != 0)
                goto sctp_bad;
#ifdef KTRACE
        if (to && (KTRPOINT(td, KTR_STRUCT)))
                ktrsockaddr(to);
#endif

        iov[0].iov_base = uap->msg;
        iov[0].iov_len = uap->mlen;

        so = (struct socket *)fp->f_data;
        if (so->so_proto->pr_protocol != IPPROTO_SCTP) {
                error = EOPNOTSUPP;
                goto sctp_bad;
        }
#ifdef MAC
        error = mac_socket_check_send(td->td_ucred, so);
        if (error != 0)
                goto sctp_bad;
#endif /* MAC */

        auio.uio_iov =  iov;
        auio.uio_iovcnt = 1;
        auio.uio_segflg = UIO_USERSPACE;
        auio.uio_rw = UIO_WRITE;
        auio.uio_td = td;
        auio.uio_offset = 0;                    /* XXX */
        auio.uio_resid = 0;
#ifdef KTRACE
        if (KTRPOINT(td, KTR_GENIO))
                ktruio = cloneuio(&auio);
#endif /* KTRACE */
        len = auio.uio_resid = uap->mlen;
        CURVNET_SET(so->so_vnet);
        error = sctp_lower_sosend(so, to, &auio, (struct mbuf *)NULL,
            (struct mbuf *)NULL, uap->flags, u_sinfo, td);
        CURVNET_RESTORE();
        if (error != 0) {
                if (auio.uio_resid != len && (error == ERESTART ||
                    error == EINTR || error == EWOULDBLOCK))
                        error = 0;
                /* Generation of SIGPIPE can be controlled per socket. */
                if (error == EPIPE && !(so->so_options & SO_NOSIGPIPE) &&
                    !(uap->flags & MSG_NOSIGNAL)) {
                        PROC_LOCK(td->td_proc);
                        tdsignal(td, SIGPIPE);
                        PROC_UNLOCK(td->td_proc);
                }
        }
        if (error == 0)
                td->td_retval[0] = len - auio.uio_resid;
#ifdef KTRACE
        if (ktruio != NULL) {
                if (error == 0)
                        ktruio->uio_resid = td->td_retval[0];
                ktrgenio(uap->sd, UIO_WRITE, ktruio, error);
        }
#endif /* KTRACE */
sctp_bad:
        if (fp != NULL)
                fdrop(fp, td);
sctp_bad2:
        free(to, M_SONAME);
        return (error);
}

int
sys_sctp_generic_sendmsg_iov(struct thread *td, struct sctp_generic_sendmsg_iov_args *uap)
{
        struct sctp_sndrcvinfo sinfo, *u_sinfo = NULL;
        struct socket *so;
        struct file *fp = NULL;
        struct sockaddr *to = NULL;
#ifdef KTRACE
        struct uio *ktruio = NULL;
#endif
        struct uio auio;
        struct iovec *iov, *tiov;
        cap_rights_t rights;
        ssize_t len;
        int error, i;

        if (uap->sinfo != NULL) {
                error = copyin(uap->sinfo, &sinfo, sizeof (sinfo));
                if (error != 0)
                        return (error);
                u_sinfo = &sinfo;
        }
        cap_rights_init_one(&rights, CAP_SEND);
        if (uap->tolen != 0) {
                error = getsockaddr(&to, uap->to, uap->tolen);
                if (error != 0) {
                        to = NULL;
                        goto sctp_bad2;
                }
                cap_rights_set_one(&rights, CAP_CONNECT);
        }

        AUDIT_ARG_FD(uap->sd);
        error = getsock(td, uap->sd, &rights, &fp);
        if (error != 0)
                goto sctp_bad1;

#ifdef COMPAT_FREEBSD32
        if (SV_CURPROC_FLAG(SV_ILP32))
                error = freebsd32_copyiniov((struct iovec32 *)uap->iov,
                    uap->iovlen, &iov, EMSGSIZE);
        else
#endif
                error = copyiniov(uap->iov, uap->iovlen, &iov, EMSGSIZE);
        if (error != 0)
                goto sctp_bad1;
#ifdef KTRACE
        if (to && (KTRPOINT(td, KTR_STRUCT)))
                ktrsockaddr(to);
#endif

        so = (struct socket *)fp->f_data;
        if (so->so_proto->pr_protocol != IPPROTO_SCTP) {
                error = EOPNOTSUPP;
                goto sctp_bad;
        }
#ifdef MAC
        error = mac_socket_check_send(td->td_ucred, so);
        if (error != 0)
                goto sctp_bad;
#endif /* MAC */

        auio.uio_iov = iov;
        auio.uio_iovcnt = uap->iovlen;
        auio.uio_segflg = UIO_USERSPACE;
        auio.uio_rw = UIO_WRITE;
        auio.uio_td = td;
        auio.uio_offset = 0;                    /* XXX */
        auio.uio_resid = 0;
        tiov = iov;
        for (i = 0; i <uap->iovlen; i++, tiov++) {
                if ((auio.uio_resid += tiov->iov_len) < 0) {
                        error = EINVAL;
                        goto sctp_bad;
                }
        }
#ifdef KTRACE
        if (KTRPOINT(td, KTR_GENIO))
                ktruio = cloneuio(&auio);
#endif /* KTRACE */
        len = auio.uio_resid;
        CURVNET_SET(so->so_vnet);
        error = sctp_lower_sosend(so, to, &auio,
                    (struct mbuf *)NULL, (struct mbuf *)NULL,
                    uap->flags, u_sinfo, td);
        CURVNET_RESTORE();
        if (error != 0) {
                if (auio.uio_resid != len && (error == ERESTART ||
                    error == EINTR || error == EWOULDBLOCK))
                        error = 0;
                /* Generation of SIGPIPE can be controlled per socket */
                if (error == EPIPE && !(so->so_options & SO_NOSIGPIPE) &&
                    !(uap->flags & MSG_NOSIGNAL)) {
                        PROC_LOCK(td->td_proc);
                        tdsignal(td, SIGPIPE);
                        PROC_UNLOCK(td->td_proc);
                }
        }
        if (error == 0)
                td->td_retval[0] = len - auio.uio_resid;
#ifdef KTRACE
        if (ktruio != NULL) {
                if (error == 0)
                        ktruio->uio_resid = td->td_retval[0];
                ktrgenio(uap->sd, UIO_WRITE, ktruio, error);
        }
#endif /* KTRACE */
sctp_bad:
        free(iov, M_IOV);
sctp_bad1:
        if (fp != NULL)
                fdrop(fp, td);
sctp_bad2:
        free(to, M_SONAME);
        return (error);
}

int
sys_sctp_generic_recvmsg(struct thread *td, struct sctp_generic_recvmsg_args *uap)
{
        uint8_t sockbufstore[256];
        struct uio auio;
        struct iovec *iov, *tiov;
        struct sctp_sndrcvinfo sinfo;
        struct socket *so;
        struct file *fp = NULL;
        struct sockaddr *fromsa;
        cap_rights_t rights;
#ifdef KTRACE
        struct uio *ktruio = NULL;
#endif
        ssize_t len;
        int error, fromlen, i, msg_flags;

        AUDIT_ARG_FD(uap->sd);
        error = getsock(td, uap->sd, cap_rights_init_one(&rights, CAP_RECV),
            &fp);
        if (error != 0)
                return (error);
#ifdef COMPAT_FREEBSD32
        if (SV_CURPROC_FLAG(SV_ILP32))
                error = freebsd32_copyiniov((struct iovec32 *)uap->iov,
                    uap->iovlen, &iov, EMSGSIZE);
        else
#endif
                error = copyiniov(uap->iov, uap->iovlen, &iov, EMSGSIZE);
        if (error != 0)
                goto out1;

        so = fp->f_data;
        if (so->so_proto->pr_protocol != IPPROTO_SCTP) {
                error = EOPNOTSUPP;
                goto out;
        }
#ifdef MAC
        error = mac_socket_check_receive(td->td_ucred, so);
        if (error != 0)
                goto out;
#endif /* MAC */

        if (uap->fromlenaddr != NULL) {
                error = copyin(uap->fromlenaddr, &fromlen, sizeof (fromlen));
                if (error != 0)
                        goto out;
        } else {
                fromlen = 0;
        }
        if (uap->msg_flags) {
                error = copyin(uap->msg_flags, &msg_flags, sizeof (int));
                if (error != 0)
                        goto out;
        } else {
                msg_flags = 0;
        }
        auio.uio_iov = iov;
        auio.uio_iovcnt = uap->iovlen;
        auio.uio_segflg = UIO_USERSPACE;
        auio.uio_rw = UIO_READ;
        auio.uio_td = td;
        auio.uio_offset = 0;                    /* XXX */
        auio.uio_resid = 0;
        tiov = iov;
        for (i = 0; i <uap->iovlen; i++, tiov++) {
                if ((auio.uio_resid += tiov->iov_len) < 0) {
                        error = EINVAL;
                        goto out;
                }
        }
        len = auio.uio_resid;
        fromsa = (struct sockaddr *)sockbufstore;

#ifdef KTRACE
        if (KTRPOINT(td, KTR_GENIO))
                ktruio = cloneuio(&auio);
#endif /* KTRACE */
        memset(&sinfo, 0, sizeof(struct sctp_sndrcvinfo));
        CURVNET_SET(so->so_vnet);
        error = sctp_sorecvmsg(so, &auio, (struct mbuf **)NULL,
                    fromsa, fromlen, &msg_flags,
                    (struct sctp_sndrcvinfo *)&sinfo, 1);
        CURVNET_RESTORE();
        if (error != 0) {
                if (auio.uio_resid != len && (error == ERESTART ||
                    error == EINTR || error == EWOULDBLOCK))
                        error = 0;
        } else {
                if (uap->sinfo)
                        error = copyout(&sinfo, uap->sinfo, sizeof (sinfo));
        }
#ifdef KTRACE
        if (ktruio != NULL) {
                ktruio->uio_resid = len - auio.uio_resid;
                ktrgenio(uap->sd, UIO_READ, ktruio, error);
        }
#endif /* KTRACE */
        if (error != 0)
                goto out;
        td->td_retval[0] = len - auio.uio_resid;

        if (fromlen && uap->from) {
                len = fromlen;
                if (len <= 0 || fromsa == NULL)
                        len = 0;
                else {
                        len = MIN(len, fromsa->sa_len);
                        error = copyout(fromsa, uap->from, (size_t)len);
                        if (error != 0)
                                goto out;
                }
                error = copyout(&len, uap->fromlenaddr, sizeof (socklen_t));
                if (error != 0)
                        goto out;
        }
#ifdef KTRACE
        if (KTRPOINT(td, KTR_STRUCT))
                ktrsockaddr(fromsa);
#endif
        if (uap->msg_flags) {
                error = copyout(&msg_flags, uap->msg_flags, sizeof (int));
                if (error != 0)
                        goto out;
        }
out:
        free(iov, M_IOV);
out1:
        if (fp != NULL)
                fdrop(fp, td);

        return (error);
}