text: /*
   * clnt_tcp.c, Implements a TCP/IP based, client side RPC.
   *
   * Copyright (c) 2010, Oracle America, Inc.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are
   * met:
   *
   *     * Redistributions of source code must retain the above copyright
   *       notice, this list of conditions and the following disclaimer.
   *     * 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.
   *     * Neither the name of the "Oracle America, 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 HOLDER 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.
   *
   * TCP based RPC supports 'batched calls'.
   * A sequence of calls may be batched-up in a send buffer.  The rpc call
   * return immediately to the client even though the call was not necessarily
   * sent.  The batching occurs if the results' xdr routine is NULL (0) AND
   * the rpc timeout value is zero (see clnt.h, rpc).
   *
   * Clients should NOT casually batch calls that in fact return results; that is,
   * the server side should be aware that a call is batched and not produce any
   * return message.  Batched calls that produce many result messages can
   * deadlock (netlock) the client and the server....
   *
   * Now go hang yourself.
   */
  
  #include <errno.h>
  #include <libintl.h>
  #include <netdb.h>
  #include <rpc/pmap_clnt.h>
  #include <rpc/rpc.h>
  #include <shlib-compat.h>
  #include <stdio.h>
  #include <sys/poll.h>
  #include <sys/socket.h>
  #include <unistd.h>
  #include <wchar.h>
  
  extern u_long _create_xid(void);
  
  #define MCALL_MSG_SIZE 24
  
  struct ct_data
  {
      int ct_sock;
      bool_t ct_closeit;
      struct timeval ct_wait;
      bool_t ct_waitset; /* wait set by clnt_control? */
      struct sockaddr_in ct_addr;
      struct rpc_err ct_error;
      char ct_mcall[MCALL_MSG_SIZE]; /* marshalled callmsg */
      u_int ct_mpos;                 /* pos after marshal */
      XDR ct_xdrs;
  };
  
  static int readtcp(char*, char*, int);
  static int writetcp(char*, char*, int);
  
  static enum clnt_stat clnttcp_call(CLIENT*, u_long, xdrproc_t, caddr_t,
                                     xdrproc_t, caddr_t, struct timeval);
  static void clnttcp_abort(void);
  static void clnttcp_geterr(CLIENT*, struct rpc_err*);
  static bool_t clnttcp_freeres(CLIENT*, xdrproc_t, caddr_t);
  static bool_t clnttcp_control(CLIENT*, int, char*);
  static void clnttcp_destroy(CLIENT*);
  
  static const struct clnt_ops tcp_ops = {clnttcp_call,    clnttcp_abort,
                                          clnttcp_geterr,  clnttcp_freeres,
                                          clnttcp_destroy, clnttcp_control};
  
  /*
   * Create a client handle for a tcp/ip connection.
   * If *sockp<0, *sockp is set to a newly created TCP socket and it is
   * connected to raddr.  If *sockp non-negative then
   * raddr is ignored.  The rpc/tcp package does buffering
   * similar to stdio, so the client must pick send and receive buffer sizes,];
   * 0 => use the default.
   * If raddr->sin_port is 0, then a binder on the remote machine is
   * consulted for the right port number.
   * NB: *sockp is copied into a private area.
   * NB: It is the clients responsibility to close *sockp.
   * NB: The rpch->cl_auth is set null authentication.  Caller may wish to set
   * this something more useful.
   */
  CLIENT* clnttcp_create(struct sockaddr_in* raddr, u_long prog, u_long vers,
                         int* sockp, u_int sendsz, u_int recvsz)
  {
      CLIENT* h;
      struct ct_data* ct;
      struct rpc_msg call_msg;
  
      h = (CLIENT*)mem_alloc(sizeof(*h));
      ct = (struct ct_data*)mem_alloc(sizeof(*ct));
      if (h == NULL || ct == NULL)
      {
          struct rpc_createerr* ce = &get_rpc_createerr();
          (void)__fxprintf(NULL, "%s: %s", __func__, _("out of memory\n"));
          ce->cf_stat = RPC_SYSTEMERROR;
          ce->cf_error.re_errno = ENOMEM;
          goto fooy;
      }
  
      /*
       * If no port number given ask the pmap for one
       */
      if (raddr->sin_port == 0)
      {
          u_short port;
          if ((port = pmap_getport(raddr, prog, vers, IPPROTO_TCP)) == 0)
          {
              mem_free((caddr_t)ct, sizeof(struct ct_data));
              mem_free((caddr_t)h, sizeof(CLIENT));
              return ((CLIENT*)NULL);
          }
          raddr->sin_port = htons(port);
      }
  
      /*
       * If no socket given, open one
       */
      if (*sockp < 0)
      {
          *sockp = __socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
          (void)bindresvport(*sockp, (struct sockaddr_in*)0);
          if ((*sockp < 0) ||
              (__connect(*sockp, (struct sockaddr*)raddr, sizeof(*raddr)) < 0))
          {
              struct rpc_createerr* ce = &get_rpc_createerr();
              ce->cf_stat = RPC_SYSTEMERROR;
              ce->cf_error.re_errno = errno;
              if (*sockp >= 0)
                  (void)__close(*sockp);
              goto fooy;
          }
          ct->ct_closeit = TRUE;
      }
      else
      {
          ct->ct_closeit = FALSE;
      }
  
      /*
       * Set up private data struct
       */
      ct->ct_sock = *sockp;
      ct->ct_wait.tv_usec = 0;
      ct->ct_waitset = FALSE;
      ct->ct_addr = *raddr;
  
      /*
       * Initialize call message
       */
      call_msg.rm_xid = _create_xid();
      call_msg.rm_direction = CALL;
      call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
      call_msg.rm_call.cb_prog = prog;
      call_msg.rm_call.cb_vers = vers;
  
      /*
       * pre-serialize the static part of the call msg and stash it away
       */
      xdrmem_create(&(ct->ct_xdrs), ct->ct_mcall, MCALL_MSG_SIZE, XDR_ENCODE);
      if (!xdr_callhdr(&(ct->ct_xdrs), &call_msg))
      {
          if (ct->ct_closeit)
          {
              (void)__close(*sockp);
          }
          goto fooy;
      }
      ct->ct_mpos = XDR_GETPOS(&(ct->ct_xdrs));
      XDR_DESTROY(&(ct->ct_xdrs));
  
      /*
       * Create a client handle which uses xdrrec for serialization
       * and authnone for authentication.
       */
      xdrrec_create(&(ct->ct_xdrs), sendsz, recvsz, (caddr_t)ct, readtcp,
                    writetcp);
      h->cl_ops = (struct clnt_ops*)&tcp_ops;
      h->cl_private = (caddr_t)ct;
      h->cl_auth = authnone_create();
      return h;
  
  fooy:
      /*
       * Something goofed, free stuff and barf
       */
      mem_free((caddr_t)ct, sizeof(struct ct_data));
      mem_free((caddr_t)h, sizeof(CLIENT));
      return ((CLIENT*)NULL);
  }
  #ifdef EXPORT_RPC_SYMBOLS
  libc_hidden_def(clnttcp_create)
  #else
  libc_hidden_nolink_sunrpc(clnttcp_create, GLIBC_2_0)
  #endif
  
      static enum clnt_stat
      clnttcp_call(CLIENT* h, u_long proc, xdrproc_t xdr_args, caddr_t args_ptr,
                   xdrproc_t xdr_results, caddr_t results_ptr,
                   struct timeval timeout)
  {
      struct ct_data* ct = (struct ct_data*)h->cl_private;
      XDR* xdrs = &(ct->ct_xdrs);
      struct rpc_msg reply_msg;
      u_long x_id;
      uint32_t* msg_x_id = (uint32_t*)(ct->ct_mcall); /* yuk */
      bool_t shipnow;
      int refreshes = 2;
  
      if (!ct->ct_waitset)
      {
          ct->ct_wait = timeout;
      }
  
      shipnow = (xdr_results == (xdrproc_t)0 && ct->ct_wait.tv_sec == 0 &&
                 ct->ct_wait.tv_usec == 0)
                    ? FALSE
                    : TRUE;
  
  call_again:
      xdrs->x_op = XDR_ENCODE;
      ct->ct_error.re_status = RPC_SUCCESS;
      x_id = ntohl(--(*msg_x_id));
      if ((!XDR_PUTBYTES(xdrs, ct->ct_mcall, ct->ct_mpos)) ||
          (!XDR_PUTLONG(xdrs, (long*)&proc)) ||
          (!AUTH_MARSHALL(h->cl_auth, xdrs)) || (!(*xdr_args)(xdrs, args_ptr)))
      {
          if (ct->ct_error.re_status == RPC_SUCCESS)
              ct->ct_error.re_status = RPC_CANTENCODEARGS;
          (void)xdrrec_endofrecord(xdrs, TRUE);
          return (ct->ct_error.re_status);
      }
      if (!xdrrec_endofrecord(xdrs, shipnow))
          return ct->ct_error.re_status = RPC_CANTSEND;
      if (!shipnow)
          return RPC_SUCCESS;
      /*
       * Hack to provide rpc-based message passing
       */
      if (ct->ct_wait.tv_sec == 0 && ct->ct_wait.tv_usec == 0)
      {
          return ct->ct_error.re_status = RPC_TIMEDOUT;
      }
  
      /*
       * Keep receiving until we get a valid transaction id
       */
      xdrs->x_op = XDR_DECODE;
      while (TRUE)
      {
          reply_msg.acpted_rply.ar_verf = _null_auth;
          reply_msg.acpted_rply.ar_results.where = NULL;
          reply_msg.acpted_rply.ar_results.proc = (xdrproc_t)xdr_void;
          if (!xdrrec_skiprecord(xdrs))
              return (ct->ct_error.re_status);
          /* now decode and validate the response header */
          if (!xdr_replymsg(xdrs, &reply_msg))
          {
              if (ct->ct_error.re_status == RPC_SUCCESS)
                  continue;
              return ct->ct_error.re_status;
          }
          if ((uint32_t)reply_msg.rm_xid == (uint32_t)x_id)
              break;
      }
  
      /*
       * process header
       */
      _seterr_reply(&reply_msg, &(ct->ct_error));
      if (ct->ct_error.re_status == RPC_SUCCESS)
      {
          if (!AUTH_VALIDATE(h->cl_auth, &reply_msg.acpted_rply.ar_verf))
          {
              ct->ct_error.re_status = RPC_AUTHERROR;
              ct->ct_error.re_why = AUTH_INVALIDRESP;
          }
          else if (!(*xdr_results)(xdrs, results_ptr))
          {
              if (ct->ct_error.re_status == RPC_SUCCESS)
                  ct->ct_error.re_status = RPC_CANTDECODERES;
          }
          /* free verifier ... */
          if (reply_msg.acpted_rply.ar_verf.oa_base != NULL)
          {
              xdrs->x_op = XDR_FREE;
              (void)xdr_opaque_auth(xdrs, &(reply_msg.acpted_rply.ar_verf));
          }
      } /* end successful completion */
      else
      {
          /* maybe our credentials need to be refreshed ... */
          if (refreshes-- && AUTH_REFRESH(h->cl_auth))
              goto call_again;
      } /* end of unsuccessful completion */
      return ct->ct_error.re_status;
  }
  
  static void clnttcp_geterr(CLIENT* h, struct rpc_err* errp)
  {
      struct ct_data* ct = (struct ct_data*)h->cl_private;
  
      *errp = ct->ct_error;
  }
  
  static bool_t clnttcp_freeres(CLIENT* cl, xdrproc_t xdr_res, caddr_t res_ptr)
  {
      struct ct_data* ct = (struct ct_data*)cl->cl_private;
      XDR* xdrs = &(ct->ct_xdrs);
  
      xdrs->x_op = XDR_FREE;
      return (*xdr_res)(xdrs, res_ptr);
  }
  
  static void clnttcp_abort(void)
  {
  }
  
  static bool_t clnttcp_control(CLIENT* cl, int request, char* info)
  {
      struct ct_data* ct = (struct ct_data*)cl->cl_private;
      u_long ul;
      uint32_t ui32;
  
      switch (request)
      {
          case CLSET_FD_CLOSE:
              ct->ct_closeit = TRUE;
              break;
          case CLSET_FD_NCLOSE:
              ct->ct_closeit = FALSE;
              break;
          case CLSET_TIMEOUT:
              ct->ct_wait = *(struct timeval*)info;
              ct->ct_waitset = TRUE;
              break;
          case CLGET_TIMEOUT:
              *(struct timeval*)info = ct->ct_wait;
              break;
          case CLGET_SERVER_ADDR:
              *(struct sockaddr_in*)info = ct->ct_addr;
              break;
          case CLGET_FD:
              *(int*)info = ct->ct_sock;
              break;
          case CLGET_XID:
              /*
               * use the knowledge that xid is the
               * first element in the call structure *.
               * This will get the xid of the PREVIOUS call
               */
              memcpy(&ui32, ct->ct_mcall, sizeof(ui32));
              ul = ntohl(ui32);
              memcpy(info, &ul, sizeof(ul));
              break;
          case CLSET_XID:
              /* This will set the xid of the NEXT call */
              memcpy(&ul, info, sizeof(ul));
              ui32 = htonl(ul - 1);
              memcpy(ct->ct_mcall, &ui32, sizeof(ui32));
              /* decrement by 1 as clnttcp_call() increments once */
              break;
          case CLGET_VERS:
              /*
               * This RELIES on the information that, in the call body,
               * the version number field is the fifth field from the
               * beginning of the RPC header. MUST be changed if the
               * call_struct is changed
               */
              memcpy(&ui32, ct->ct_mcall + 4 * BYTES_PER_XDR_UNIT, sizeof(ui32));
              ul = ntohl(ui32);
              memcpy(info, &ul, sizeof(ul));
              break;
          case CLSET_VERS:
              memcpy(&ul, info, sizeof(ul));
              ui32 = htonl(ul);
              memcpy(ct->ct_mcall + 4 * BYTES_PER_XDR_UNIT, &ui32, sizeof(ui32));
              break;
          case CLGET_PROG:
              /*
               * This RELIES on the information that, in the call body,
               * the program number field is the  field from the
               * beginning of the RPC header. MUST be changed if the
               * call_struct is changed
               */
              memcpy(&ui32, ct->ct_mcall + 3 * BYTES_PER_XDR_UNIT, sizeof(ui32));
              ul = ntohl(ui32);
              memcpy(info, &ul, sizeof(ul));
              break;
          case CLSET_PROG:
              memcpy(&ul, info, sizeof(ul));
              ui32 = htonl(ul);
              memcpy(ct->ct_mcall + 3 * BYTES_PER_XDR_UNIT, &ui32, sizeof(ui32));
              break;
          /* The following are only possible with TI-RPC */
          case CLGET_RETRY_TIMEOUT:
          case CLSET_RETRY_TIMEOUT:
          case CLGET_SVC_ADDR:
          case CLSET_SVC_ADDR:
          case CLSET_PUSH_TIMOD:
          case CLSET_POP_TIMOD:
          default:
              return FALSE;
      }
      return TRUE;
  }
  
  static void clnttcp_destroy(CLIENT* h)
  {
      struct ct_data* ct = (struct ct_data*)h->cl_private;
  
      if (ct->ct_closeit)
      {
          (void)__close(ct->ct_sock);
      }
      XDR_DESTROY(&(ct->ct_xdrs));
      mem_free((caddr_t)ct, sizeof(struct ct_data));
      mem_free((caddr_t)h, sizeof(CLIENT));
  }
  
  /*
   * Interface between xdr serializer and tcp connection.
   * Behaves like the system calls, read & write, but keeps some error state
   * around for the rpc level.
   */
  static int readtcp(char* ctptr, char* buf, int len)
  {
      struct ct_data* ct = (struct ct_data*)ctptr;
      struct pollfd fd;
      int milliseconds =
          (ct->ct_wait.tv_sec * 1000) + (ct->ct_wait.tv_usec / 1000);
  
      if (len == 0)
          return 0;
  
      fd.fd = ct->ct_sock;
      fd.events = POLLIN;
      while (TRUE)
      {
          switch (__poll(&fd, 1, milliseconds))
          {
              case 0:
                  ct->ct_error.re_status = RPC_TIMEDOUT;
                  return -1;
  
              case -1:
                  if (errno == EINTR)
                      continue;
                  ct->ct_error.re_status = RPC_CANTRECV;
                  ct->ct_error.re_errno = errno;
                  return -1;
          }
          break;
      }
      switch (len = __read(ct->ct_sock, buf, len))
      {
  
          case 0:
              /* premature eof */
              ct->ct_error.re_errno = ECONNRESET;
              ct->ct_error.re_status = RPC_CANTRECV;
              len = -1; /* it's really an error */
              break;
  
          case -1:
              ct->ct_error.re_errno = errno;
              ct->ct_error.re_status = RPC_CANTRECV;
              break;
      }
      return len;
  }
  
  static int writetcp(char* ctptr, char* buf, int len)
  {
      int i, cnt;
      struct ct_data* ct = (struct ct_data*)ctptr;
  
      for (cnt = len; cnt > 0; cnt -= i, buf += i)
      {
          if ((i = __write(ct->ct_sock, buf, cnt)) == -1)
          {
              ct->ct_error.re_errno = errno;
              ct->ct_error.re_status = RPC_CANTSEND;
              return -1;
          }
      }
      return len;
  }
  