/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to

 * deal in the Software without restriction, including without limitation the

 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or

 * sell copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS

 * IN THE SOFTWARE.

 */

#include "uv.h"

#include "internal.h"

#include <assert.h>

#include <errno.h>

#include <string.h>

#include <sys/un.h>

#include <unistd.h>

#include <stdlib.h>

/* Does the file path contain embedded nul bytes? */

static int includes_invalid_nul(const char *s, size_t n) {

  if (n == 0)

    return 0;

#ifdef __linux__

  /* Accept abstract socket namespace paths, throughout which nul bytes have

   * no special significance ("\0foo\0bar").

   */

  if (s[0] == '\0')

    return 0;

#endif

  return NULL != memchr(s, '\0', n);

}

int uv_pipe_init(uv_loop_t* loop, uv_pipe_t* handle, int ipc) {

  uv__stream_init(loop, (uv_stream_t*)handle, UV_NAMED_PIPE);

  handle->shutdown_req = NULL;

  handle->connect_req = NULL;

  handle->pipe_fname = NULL;

  handle->ipc = ipc;

  return 0;

}

int uv_pipe_bind(uv_pipe_t* handle, const char* name) {

  return uv_pipe_bind2(handle, name, strlen(name), 0);

}

int uv_pipe_bind2(uv_pipe_t* handle,

                  const char* name,

                  size_t namelen,

                  unsigned int flags) {

  struct sockaddr_un saddr;

  char* pipe_fname = NULL;

  int sockfd = -1;

  int err;

  socklen_t addrlen;

  if (flags & ~UV_PIPE_NO_TRUNCATE)

    return UV_EINVAL;

  if (name == NULL)

    return UV_EINVAL;

  /* namelen==0 on Linux means autobind the listen socket in the abstract

   * socket namespace, see `man 7 unix` for details.

   */

#if !defined(__linux__)

  if (namelen == 0)

    return UV_EINVAL;

#endif

  if (includes_invalid_nul(name, namelen))

    return UV_EINVAL;

  if (flags & UV_PIPE_NO_TRUNCATE)

    if (namelen > sizeof(saddr.sun_path))

      return UV_EINVAL;

  /* Truncate long paths. Documented behavior. */

  if (namelen > sizeof(saddr.sun_path))

    namelen = sizeof(saddr.sun_path);

  /* Already bound? */

  if (uv__stream_fd(handle) >= 0)

    return UV_EINVAL;

  if (uv__is_closing(handle))

    return UV_EINVAL;

  /* Make a copy of the file path unless it is an abstract socket.

   * We unlink the file later but abstract sockets disappear

   * automatically since they're not real file system entities.

   */

  if (*name == '\0') {

    addrlen = offsetof(struct sockaddr_un, sun_path) + namelen;

  } else {

    pipe_fname = uv__malloc(namelen + 1);

    if (pipe_fname == NULL)

      return UV_ENOMEM;

    memcpy(pipe_fname, name, namelen);

    pipe_fname[namelen] = '\0';

    addrlen = sizeof saddr;

  }

  err = uv__socket(AF_UNIX, SOCK_STREAM, 0);

  if (err < 0)

    goto err_socket;

  sockfd = err;

  memset(&saddr, 0, sizeof saddr);

  memcpy(&saddr.sun_path, name, namelen);

  saddr.sun_family = AF_UNIX;

  if (bind(sockfd, (struct sockaddr*)&saddr, addrlen)) {

    err = UV__ERR(errno);

    /* Convert ENOENT to EACCES for compatibility with Windows. */

    if (err == UV_ENOENT)

      err = UV_EACCES;

    uv__close(sockfd);

    goto err_socket;

  }

  /* Success. */

  handle->flags |= UV_HANDLE_BOUND;

  handle->pipe_fname = pipe_fname; /* NULL or a copy of |name| */

  handle->io_watcher.fd = sockfd;

  return 0;

err_socket:

  uv__free(pipe_fname);

  return err;

}

int uv__pipe_listen(uv_pipe_t* handle, int backlog, uv_connection_cb cb) {

  if (uv__stream_fd(handle) == -1)

    return UV_EINVAL;

  if (handle->ipc)

    return UV_EINVAL;

#if defined(__MVS__) || defined(__PASE__)

  /* On zOS, backlog=0 has undefined behaviour */

  /* On IBMi PASE, backlog=0 leads to "Connection refused" error */

  if (backlog == 0)

    backlog = 1;

  else if (backlog < 0)

    backlog = SOMAXCONN;

#endif

  if (listen(uv__stream_fd(handle), backlog))

    return UV__ERR(errno);

  handle->connection_cb = cb;

  uv__io_cb_set(&handle->io_watcher, UV__SERVER_IO);

  return uv__io_start(handle->loop, &handle->io_watcher, POLLIN);

}

void uv__pipe_close(uv_pipe_t* handle) {

  if (handle->pipe_fname) {

    /*

     * Unlink the file system entity before closing the file descriptor.

     * Doing it the other way around introduces a race where our process

     * unlinks a socket with the same name that's just been created by

     * another thread or process.

     */

    unlink(handle->pipe_fname);

    uv__free((void*)handle->pipe_fname);

    handle->pipe_fname = NULL;

  }

  uv__stream_close((uv_stream_t*)handle);

}

int uv_pipe_open(uv_pipe_t* handle, uv_file fd) {

  int flags;

  int mode;

  int err;

  flags = 0;

  if (uv__fd_exists(handle->loop, fd))

    return UV_EEXIST;

  do

    mode = fcntl(fd, F_GETFL);

  while (mode == -1 && errno == EINTR);

  if (mode == -1)

    return UV__ERR(errno); /* according to docs, must be EBADF */

  err = uv__nonblock(fd, 1);

  if (err)

    return err;

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

  err = uv__stream_try_select((uv_stream_t*) handle, &fd);

  if (err)

    return err;

#endif /* defined(__APPLE__) */

  mode &= O_ACCMODE;

  if (mode != O_WRONLY)

    flags |= UV_HANDLE_READABLE;

  if (mode != O_RDONLY)

    flags |= UV_HANDLE_WRITABLE;

  return uv__stream_open((uv_stream_t*)handle, fd, flags);

}

void uv_pipe_connect(uv_connect_t* req,

                    uv_pipe_t* handle,

                    const char* name,

                    uv_connect_cb cb) {

  int err;

  err = uv_pipe_connect2(req, handle, name, strlen(name), 0, cb);

  if (err) {

    handle->delayed_error = err;

    handle->connect_req = req;

    uv__req_init(handle->loop, req, UV_CONNECT);

    req->handle = (uv_stream_t*) handle;

    req->cb = cb;

    uv__queue_init(&req->queue);

    /* Force callback to run on next tick in case of error. */

    uv__io_feed(handle->loop, &handle->io_watcher);

  }

}

int uv_pipe_connect2(uv_connect_t* req,

                     uv_pipe_t* handle,

                     const char* name,

                     size_t namelen,

                     unsigned int flags,

                     uv_connect_cb cb) {

  struct sockaddr_un saddr;

  int new_sock;

  int err;

  int r;

  socklen_t addrlen;

  if (flags & ~UV_PIPE_NO_TRUNCATE)

    return UV_EINVAL;

  if (name == NULL)

    return UV_EINVAL;

  if (namelen == 0)

    return UV_EINVAL;

  if (includes_invalid_nul(name, namelen))

    return UV_EINVAL;

  if (flags & UV_PIPE_NO_TRUNCATE)

    if (namelen > sizeof(saddr.sun_path))

      return UV_EINVAL;

  /* Truncate long paths. Documented behavior. */

  if (namelen > sizeof(saddr.sun_path))

    namelen = sizeof(saddr.sun_path);

  new_sock = (uv__stream_fd(handle) == -1);

  if (new_sock) {

    err = uv__socket(AF_UNIX, SOCK_STREAM, 0);

    if (err < 0)

      goto out;

    handle->io_watcher.fd = err;

  }

  memset(&saddr, 0, sizeof saddr);

  memcpy(&saddr.sun_path, name, namelen);

  saddr.sun_family = AF_UNIX;

  if (*name == '\0')

    addrlen = offsetof(struct sockaddr_un, sun_path) + namelen;

  else

    addrlen = sizeof saddr;

  do {

    r = connect(uv__stream_fd(handle), (struct sockaddr*)&saddr, addrlen);

  }

  while (r == -1 && errno == EINTR);

  if (r == -1 && errno != EINPROGRESS) {

    err = UV__ERR(errno);

#if defined(__CYGWIN__) || defined(__MSYS__)

    /* EBADF is supposed to mean that the socket fd is bad, but

       Cygwin reports EBADF instead of ENOTSOCK when the file is

       not a socket.  We do not expect to see a bad fd here

       (e.g. due to new_sock), so translate the error.  */

    if (err == UV_EBADF)

      err = UV_ENOTSOCK;

#endif

    goto out;

  }

  err = 0;

  if (new_sock) {

    err = uv__stream_open((uv_stream_t*)handle,

                          uv__stream_fd(handle),

                          UV_HANDLE_READABLE | UV_HANDLE_WRITABLE);

  }

  if (err == 0)

    uv__io_start(handle->loop, &handle->io_watcher, POLLOUT);

out:

  handle->delayed_error = err;

  handle->connect_req = req;

  uv__req_init(handle->loop, req, UV_CONNECT);

  req->handle = (uv_stream_t*) handle;

  req->cb = cb;

  uv__queue_init(&req->queue);

  /* Force callback to run on next tick in case of error. */

  if (err)

    uv__io_feed(handle->loop, &handle->io_watcher);

  return 0;

}

static int uv__pipe_getsockpeername(const uv_pipe_t* handle,

                                    uv__peersockfunc func,

                                    char* buffer,

                                    size_t* size) {

#if defined(__linux__)

  static const int is_linux = 1;

#else

  static const int is_linux = 0;

#endif

  struct sockaddr_un sa;

  socklen_t addrlen;

  size_t slop;

  char* p;

  int err;

  if (buffer == NULL || size == NULL || *size == 0)

    return UV_EINVAL;

  addrlen = sizeof(sa);

  memset(&sa, 0, addrlen);

  err = uv__getsockpeername((const uv_handle_t*) handle,

                            func,

                            (struct sockaddr*) &sa,

                            (int*) &addrlen);

  if (err < 0) {

    *size = 0;

    return err;

  }

  slop = 1;

  if (is_linux && sa.sun_path[0] == '\0') {

    /* Linux abstract namespace. Not zero-terminated. */

    slop = 0;

    addrlen -= offsetof(struct sockaddr_un, sun_path);

  } else {

    p = memchr(sa.sun_path, '\0', sizeof(sa.sun_path));

    if (p == NULL)

      p = ARRAY_END(sa.sun_path);

    addrlen = p - sa.sun_path;

  }

  if ((size_t)addrlen + slop > *size) {

    *size = addrlen + slop;

    return UV_ENOBUFS;

  }

  memcpy(buffer, sa.sun_path, addrlen);

  *size = addrlen;

  /* only null-terminate if it's not an abstract socket */

  if (buffer[0] != '\0')

    buffer[addrlen] = '\0';

  return 0;

}

int uv_pipe_getsockname(const uv_pipe_t* handle, char* buffer, size_t* size) {

  return uv__pipe_getsockpeername(handle, getsockname, buffer, size);

}

int uv_pipe_getpeername(const uv_pipe_t* handle, char* buffer, size_t* size) {

  return uv__pipe_getsockpeername(handle, getpeername, buffer, size);

}

void uv_pipe_pending_instances(uv_pipe_t* handle, int count) {

}

int uv_pipe_pending_count(uv_pipe_t* handle) {

  uv__stream_queued_fds_t* queued_fds;

  if (!handle->ipc)

    return 0;

  if (handle->accepted_fd == -1)

    return 0;

  if (handle->queued_fds == NULL)

    return 1;

  queued_fds = handle->queued_fds;

  return queued_fds->offset + 1;

}

uv_handle_type uv_pipe_pending_type(uv_pipe_t* handle) {

  if (!handle->ipc)

    return UV_UNKNOWN_HANDLE;

  if (handle->accepted_fd == -1)

    return UV_UNKNOWN_HANDLE;

  else

    return uv_guess_handle(handle->accepted_fd);

}

int uv_pipe_chmod(uv_pipe_t* handle, int mode) {

  char name_buffer[1 + UV__PATH_MAX];

  int desired_mode;

  size_t name_len;

  const char* name;

  int fd;

  int r;

  if (handle == NULL)

    return UV_EBADF;

  fd = uv__stream_fd(handle);

  if (fd == -1)

    return UV_EBADF;

  if (mode != UV_READABLE &&

      mode != UV_WRITABLE &&

      mode != (UV_WRITABLE | UV_READABLE))

    return UV_EINVAL;

  desired_mode = 0;

  if (mode & UV_READABLE)

    desired_mode |= S_IRUSR | S_IRGRP | S_IROTH;

  if (mode & UV_WRITABLE)

    desired_mode |= S_IWUSR | S_IWGRP | S_IWOTH;

  /* fchmod on macOS and (Free|Net|Open)BSD does not support UNIX sockets. */

  if (fchmod(fd, desired_mode))

    if (errno != EINVAL && errno != EOPNOTSUPP)

      return UV__ERR(errno);

  /* Fall back to chmod. */

  name_len = sizeof(name_buffer);

  r = uv_pipe_getsockname(handle, name_buffer, &name_len);

  if (r != 0)

    return r;

  name = name_buffer;

  /* On some platforms, getsockname returns an empty string, and we try with pipe_fname. */

  if (name_len == 0 && handle->pipe_fname != NULL)

    name = handle->pipe_fname;

  if (chmod(name, desired_mode))

    return UV__ERR(errno);

  return 0;

}

int uv_pipe(uv_os_fd_t fds[2], int read_flags, int write_flags) {

  uv_os_fd_t temp[2];

  int err;

#if defined(__linux__) || \

    defined(__FreeBSD__) || \

    defined(__OpenBSD__) || \

    defined(__DragonFly__) || \

    defined(__NetBSD__) || \

    defined(__illumos__) || \

    (defined(UV__SOLARIS_11_4) && UV__SOLARIS_11_4)

  int flags = O_CLOEXEC;

  if ((read_flags & UV_NONBLOCK_PIPE) && (write_flags & UV_NONBLOCK_PIPE))

    flags |= UV_FS_O_NONBLOCK;

  if (pipe2(temp, flags))

    return UV__ERR(errno);

  if (flags & UV_FS_O_NONBLOCK) {

    fds[0] = temp[0];

    fds[1] = temp[1];

    return 0;

  }

#else

  if (pipe(temp))

    return UV__ERR(errno);

  if ((err = uv__cloexec(temp[0], 1)))

    goto fail;

  if ((err = uv__cloexec(temp[1], 1)))

    goto fail;

#endif

  if (read_flags & UV_NONBLOCK_PIPE)

    if ((err = uv__nonblock(temp[0], 1)))

      goto fail;

  if (write_flags & UV_NONBLOCK_PIPE)

    if ((err = uv__nonblock(temp[1], 1)))

      goto fail;

  fds[0] = temp[0];

  fds[1] = temp[1];

  return 0;

fail:

  uv__close(temp[0]);

  uv__close(temp[1]);

  return err;

}

int uv__make_pipe(int fds[2], int flags) {

  return uv_pipe(fds,

                 flags & UV_NONBLOCK_PIPE,

                 flags & UV_NONBLOCK_PIPE);

}