* backport of "WinXP" and "Win2K3" values for %a

[Samba.git] / source / rpc_server / srv_pipe_hnd.c

/* 
 *  Unix SMB/Netbios implementation.
 *  Version 1.9.
 *  RPC Pipe client / server routines
 *  Copyright (C) Andrew Tridgell              1992-1998,
 *  Copyright (C) Luke Kenneth Casson Leighton 1996-1998,
 *  Copyright (C) Jeremy Allison                                    1999.
 *  
 *  This program 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 of the License, or
 *  (at your option) any later version.
 *  
 *  This program 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 this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */


#include "includes.h"


#define PIPE            "\\PIPE\\"
#define PIPELEN         strlen(PIPE)

static pipes_struct *chain_p;
static int pipes_open;

/*
 * Sometimes I can't decide if I hate Windows printer driver
 * writers more than I hate the Windows spooler service driver
 * writers. This gets around a combination of bugs in the spooler
 * and the HP 8500 PCL driver that causes a spooler spin. JRA.
 *
 * bumped up from 20 -> 64 after viewing traffic from WordPerfect 
 * 2002 running on NT 4.- SP6
 */

#ifndef MAX_OPEN_SPOOLSS_PIPES
#define MAX_OPEN_SPOOLSS_PIPES 256
#endif
static int current_spoolss_pipes_open;

static pipes_struct *Pipes;
static struct bitmap *bmap;

/****************************************************************************
 Pipe iterator functions.
****************************************************************************/

pipes_struct *get_first_pipe(void)
{
        return Pipes;
}

pipes_struct *get_next_pipe(pipes_struct *p)
{
        return p->next;
}

/* this must be larger than the sum of the open files and directories */
static int pipe_handle_offset;

/****************************************************************************
 Set the pipe_handle_offset. Called from smbd/files.c
****************************************************************************/

void set_pipe_handle_offset(int max_open_files)
{
  if(max_open_files < 0x7000)
    pipe_handle_offset = 0x7000;
  else
    pipe_handle_offset = max_open_files + 10; /* For safety. :-) */
}

/****************************************************************************
 Reset pipe chain handle number.
****************************************************************************/
void reset_chain_p(void)
{
        chain_p = NULL;
}

/****************************************************************************
 Initialise pipe handle states.
****************************************************************************/

void init_rpc_pipe_hnd(void)
{
        bmap = bitmap_allocate(MAX_OPEN_PIPES);
        if (!bmap)
                exit_server("out of memory in init_rpc_pipe_hnd");
}

/****************************************************************************
 Initialise an outgoing packet.
****************************************************************************/

static BOOL pipe_init_outgoing_data(pipes_struct *p)
{
        output_data *o_data = &p->out_data;

        /* Reset the offset counters. */
        o_data->data_sent_length = 0;
        o_data->current_pdu_len = 0;
        o_data->current_pdu_sent = 0;

        memset(o_data->current_pdu, '\0', sizeof(o_data->current_pdu));

        /* Free any memory in the current return data buffer. */
        prs_mem_free(&o_data->rdata);

        /*
         * Initialize the outgoing RPC data buffer.
         * we will use this as the raw data area for replying to rpc requests.
         */     
        if(!prs_init(&o_data->rdata, MAX_PDU_FRAG_LEN, p->mem_ctx, MARSHALL)) {
                DEBUG(0,("pipe_init_outgoing_data: malloc fail.\n"));
                return False;
        }

        return True;
}

/****************************************************************************
 Find first available pipe slot.
****************************************************************************/

pipes_struct *open_rpc_pipe_p(char *pipe_name, 
                              connection_struct *conn, uint16 vuid)
{
        int i;
        pipes_struct *p;
        static int next_pipe;
        BOOL is_spoolss_pipe = False;

        DEBUG(4,("Open pipe requested %s (pipes_open=%d)\n",
                 pipe_name, pipes_open));

        if (strstr(pipe_name, "spoolss"))
                is_spoolss_pipe = True;

        if (is_spoolss_pipe && current_spoolss_pipes_open >= MAX_OPEN_SPOOLSS_PIPES) {
                DEBUG(10,("open_rpc_pipe_p: spooler bug workaround. Denying open on pipe %s\n",
                        pipe_name ));
                return NULL;
        }

        /* not repeating pipe numbers makes it easier to track things in 
           log files and prevents client bugs where pipe numbers are reused
           over connection restarts */
        if (next_pipe == 0)
                next_pipe = (sys_getpid() ^ time(NULL)) % MAX_OPEN_PIPES;

        i = bitmap_find(bmap, next_pipe);

        if (i == -1) {
                DEBUG(0,("ERROR! Out of pipe structures\n"));
                return NULL;
        }

        next_pipe = (i+1) % MAX_OPEN_PIPES;

        for (p = Pipes; p; p = p->next)
                DEBUG(5,("open_rpc_pipe_p: name %s pnum=%x\n", p->name, p->pnum));  

        p = (pipes_struct *)malloc(sizeof(*p));

        if (!p)
                return NULL;

        ZERO_STRUCTP(p);

        if ((p->mem_ctx = talloc_init()) == NULL) {
                DEBUG(0,("open_rpc_pipe_p: talloc_init failed.\n"));
                SAFE_FREE(p);
                return NULL;
        }

        if (!init_pipe_handle_list(p, pipe_name)) {
                DEBUG(0,("open_rpc_pipe_p: init_pipe_handles failed.\n"));
                talloc_destroy(p->mem_ctx);
                SAFE_FREE(p);
                return NULL;
        }


        DLIST_ADD(Pipes, p);

        /*
         * Initialize the incoming RPC data buffer with one PDU worth of memory.
         * We cheat here and say we're marshalling, as we intend to add incoming
         * data directly into the prs_struct and we want it to auto grow. We will
         * change the type to UNMARSALLING before processing the stream.
         */

        if(!prs_init(&p->in_data.data, MAX_PDU_FRAG_LEN, p->mem_ctx, MARSHALL)) {
                DEBUG(0,("open_rpc_pipe_p: malloc fail for in_data struct.\n"));
                return NULL;
        }

        bitmap_set(bmap, i);
        i += pipe_handle_offset;

        pipes_open++;

        p->pnum = i;

        p->open = True;
        p->device_state = 0;
        p->priority = 0;
        p->conn = conn;
        p->vuid  = vuid;

        p->max_trans_reply = 0;
        
        p->ntlmssp_chal_flags = 0;
        p->ntlmssp_auth_validated = False;
        p->ntlmssp_auth_requested = False;

        p->pipe_bound = False;
        p->fault_state = False;
        p->endian = RPC_LITTLE_ENDIAN;

        /*
         * Initialize the incoming RPC struct.
         */

        p->in_data.pdu_needed_len = 0;
        p->in_data.pdu_received_len = 0;

        /*
         * Initialize the outgoing RPC struct.
         */

        p->out_data.current_pdu_len = 0;
        p->out_data.current_pdu_sent = 0;
        p->out_data.data_sent_length = 0;

        /*
         * Initialize the outgoing RPC data buffer with no memory.
         */     
        prs_init(&p->out_data.rdata, 0, p->mem_ctx, MARSHALL);
        
        ZERO_STRUCT(p->pipe_user);

        p->pipe_user.uid = (uid_t)-1;
        p->pipe_user.gid = (gid_t)-1;
        
        fstrcpy(p->name, pipe_name);
        
        DEBUG(4,("Opened pipe %s with handle %x (pipes_open=%d)\n",
                 pipe_name, i, pipes_open));
        
        chain_p = p;
        
        /* OVERWRITE p as a temp variable, to display all open pipes */ 
        for (p = Pipes; p; p = p->next)
                DEBUG(5,("open pipes: name %s pnum=%x\n", p->name, p->pnum));  

        if (is_spoolss_pipe)
                current_spoolss_pipes_open++;

        /*
         * The connection can be idled whilst this pipe is open
         * if there are no handles open. JRA.
         */

        return chain_p;
}

/****************************************************************************
 Sets the fault state on incoming packets.
****************************************************************************/

static void set_incoming_fault(pipes_struct *p)
{
        prs_mem_free(&p->in_data.data);
        p->in_data.pdu_needed_len = 0;
        p->in_data.pdu_received_len = 0;
        p->fault_state = True;
        DEBUG(10,("set_incoming_fault: Setting fault state on pipe %s : pnum = 0x%x\n",
                p->name, p->pnum ));
}

/****************************************************************************
 Ensures we have at least RPC_HEADER_LEN amount of data in the incoming buffer.
****************************************************************************/

static ssize_t fill_rpc_header(pipes_struct *p, char *data, size_t data_to_copy)
{
        size_t len_needed_to_complete_hdr = MIN(data_to_copy, RPC_HEADER_LEN - p->in_data.pdu_received_len);

        DEBUG(10,("fill_rpc_header: data_to_copy = %u, len_needed_to_complete_hdr = %u, receive_len = %u\n",
                        (unsigned int)data_to_copy, (unsigned int)len_needed_to_complete_hdr,
                        (unsigned int)p->in_data.pdu_received_len ));

        memcpy((char *)&p->in_data.current_in_pdu[p->in_data.pdu_received_len], data, len_needed_to_complete_hdr);
        p->in_data.pdu_received_len += len_needed_to_complete_hdr;

        return (ssize_t)len_needed_to_complete_hdr;
}

/****************************************************************************
 Unmarshalls a new PDU header. Assumes the raw header data is in current_in_pdu.
****************************************************************************/

static ssize_t unmarshall_rpc_header(pipes_struct *p)
{
        /*
         * Unmarshall the header to determine the needed length.
         */

        prs_struct rpc_in;

        if(p->in_data.pdu_received_len != RPC_HEADER_LEN) {
                DEBUG(0,("unmarshall_rpc_header: assert on rpc header length failed.\n"));
                set_incoming_fault(p);
                return -1;
        }

        prs_init( &rpc_in, 0, p->mem_ctx, UNMARSHALL);
        prs_set_endian_data( &rpc_in, p->endian);

        prs_give_memory( &rpc_in, (char *)&p->in_data.current_in_pdu[0],
                                        p->in_data.pdu_received_len, False);

        /*
         * Unmarshall the header as this will tell us how much
         * data we need to read to get the complete pdu.
         * This also sets the endian flag in rpc_in.
         */

        if(!smb_io_rpc_hdr("", &p->hdr, &rpc_in, 0)) {
                DEBUG(0,("unmarshall_rpc_header: failed to unmarshall RPC_HDR.\n"));
                set_incoming_fault(p);
                prs_mem_free(&rpc_in);
                return -1;
        }

        /*
         * Validate the RPC header.
         */

        if(p->hdr.major != 5 && p->hdr.minor != 0) {
                DEBUG(0,("unmarshall_rpc_header: invalid major/minor numbers in RPC_HDR.\n"));
                set_incoming_fault(p);
                prs_mem_free(&rpc_in);
                return -1;
        }

        /*
         * If there's not data in the incoming buffer this should be the start of a new RPC.
         */

        if(prs_offset(&p->in_data.data) == 0) {

                /*
                 * AS/U doesn't set FIRST flag in a BIND packet it seems.
                 */

                if ((p->hdr.pkt_type == RPC_REQUEST) && !(p->hdr.flags & RPC_FLG_FIRST)) {
                        /*
                         * Ensure that the FIRST flag is set. If not then we have
                         * a stream missmatch.
                         */

                        DEBUG(0,("unmarshall_rpc_header: FIRST flag not set in first PDU !\n"));
                        set_incoming_fault(p);
                        prs_mem_free(&rpc_in);
                        return -1;
                }

                /*
                 * If this is the first PDU then set the endianness
                 * flag in the pipe. We will need this when parsing all
                 * data in this RPC.
                 */

                p->endian = rpc_in.bigendian_data;

                DEBUG(5,("unmarshall_rpc_header: using %sendian RPC\n",
                                p->endian == RPC_LITTLE_ENDIAN ? "little-" : "big-" ));

        } else {

                /*
                 * If this is *NOT* the first PDU then check the endianness
                 * flag in the pipe is the same as that in the PDU.
                 */

                if (p->endian != rpc_in.bigendian_data) {
                        DEBUG(0,("unmarshall_rpc_header: FIRST endianness flag (%d) different in next PDU !\n", (int)p->endian));
                        set_incoming_fault(p);
                        prs_mem_free(&rpc_in);
                        return -1;
                }
        }

        /*
         * Ensure that the pdu length is sane.
         */

        if((p->hdr.frag_len < RPC_HEADER_LEN) || (p->hdr.frag_len > MAX_PDU_FRAG_LEN)) {
                DEBUG(0,("unmarshall_rpc_header: assert on frag length failed.\n"));
                set_incoming_fault(p);
                prs_mem_free(&rpc_in);
                return -1;
        }

        DEBUG(10,("unmarshall_rpc_header: type = %u, flags = %u\n", (unsigned int)p->hdr.pkt_type,
                        (unsigned int)p->hdr.flags ));

        /*
         * Adjust for the header we just ate.
         */
        p->in_data.pdu_received_len = 0;
        p->in_data.pdu_needed_len = (uint32)p->hdr.frag_len - RPC_HEADER_LEN;

        /*
         * Null the data we just ate.
         */

        memset((char *)&p->in_data.current_in_pdu[0], '\0', RPC_HEADER_LEN);

        prs_mem_free(&rpc_in);

        return 0; /* No extra data processed. */
}

/****************************************************************************
 Call this to free any talloc'ed memory. Do this before and after processing
 a complete PDU.
****************************************************************************/

void free_pipe_context(pipes_struct *p)
{
        if (p->mem_ctx) {
                DEBUG(3,("free_pipe_context: destroying talloc pool of size %u\n", talloc_pool_size(p->mem_ctx) ));
                talloc_destroy_pool(p->mem_ctx);
        } else {
                p->mem_ctx = talloc_init();
                if (p->mem_ctx == NULL)
                        p->fault_state = True;
        }
}

/****************************************************************************
 Processes a request pdu. This will do auth processing if needed, and
 appends the data into the complete stream if the LAST flag is not set.
****************************************************************************/

static BOOL process_request_pdu(pipes_struct *p, prs_struct *rpc_in_p)
{
        BOOL auth_verify = ((p->ntlmssp_chal_flags & NTLMSSP_NEGOTIATE_SIGN) != 0);
        size_t data_len = p->hdr.frag_len - RPC_HEADER_LEN - RPC_HDR_REQ_LEN -
                                (auth_verify ? RPC_HDR_AUTH_LEN : 0) - p->hdr.auth_len;

        if(!p->pipe_bound) {
                DEBUG(0,("process_request_pdu: rpc request with no bind.\n"));
                set_incoming_fault(p);
                return False;
        }

        /*
         * Check if we need to do authentication processing.
         * This is only done on requests, not binds.
         */

        /*
         * Read the RPC request header.
         */

        if(!smb_io_rpc_hdr_req("req", &p->hdr_req, rpc_in_p, 0)) {
                DEBUG(0,("process_request_pdu: failed to unmarshall RPC_HDR_REQ.\n"));
                set_incoming_fault(p);
                return False;
        }

        if(p->ntlmssp_auth_validated && !api_pipe_auth_process(p, rpc_in_p)) {
                DEBUG(0,("process_request_pdu: failed to do auth processing.\n"));
                set_incoming_fault(p);
                return False;
        }

        if (p->ntlmssp_auth_requested && !p->ntlmssp_auth_validated) {

                /*
                 * Authentication _was_ requested and it already failed.
                 */

                DEBUG(0,("process_request_pdu: RPC request received on pipe %s where \
authentication failed. Denying the request.\n", p->name));
                set_incoming_fault(p);
        return False;
    }

        /*
         * Check the data length doesn't go over the 40Mb limit.
         * increased after observing a bug in the Windows NT 4.0 SP6a
         * spoolsv.exe when the response to a GETPRINTERDRIVER2 RPC
         * will not fit in the initial buffer of size 0x1068   --jerry 22/01/2002
         */
        
        if(prs_offset(&p->in_data.data) + data_len > 40*1024*1024) {
                DEBUG(0,("process_request_pdu: rpc data buffer too large (%u) + (%u)\n",
                                (unsigned int)prs_data_size(&p->in_data.data), (unsigned int)data_len ));
                set_incoming_fault(p);
                return False;
        }

        /*
         * Append the data portion into the buffer and return.
         */

        {
                char *data_from = prs_data_p(rpc_in_p) + prs_offset(rpc_in_p);

                if(!prs_append_data(&p->in_data.data, data_from, data_len)) {
                        DEBUG(0,("process_request_pdu: Unable to append data size %u to parse buffer of size %u.\n",
                                        (unsigned int)data_len, (unsigned int)prs_data_size(&p->in_data.data) ));
                        set_incoming_fault(p);
                        return False;
                }

        }

        if(p->hdr.flags & RPC_FLG_LAST) {
                BOOL ret = False;
                /*
                 * Ok - we finally have a complete RPC stream.
                 * Call the rpc command to process it.
                 */

                /*
                 * Ensure the internal prs buffer size is *exactly* the same
                 * size as the current offset.
                 */

                if(!prs_set_buffer_size(&p->in_data.data, prs_offset(&p->in_data.data)))
                {
                        DEBUG(0,("process_request_pdu: Call to prs_set_buffer_size failed!\n"));
                        set_incoming_fault(p);
                        return False;
                }

                /*
                 * Set the parse offset to the start of the data and set the
                 * prs_struct to UNMARSHALL.
                 */

                prs_set_offset(&p->in_data.data, 0);
                prs_switch_type(&p->in_data.data, UNMARSHALL);

                /*
                 * Process the complete data stream here.
                 */

                free_pipe_context(p);

                if(pipe_init_outgoing_data(p))
                        ret = api_pipe_request(p);

                free_pipe_context(p);

                /*
                 * We have consumed the whole data stream. Set back to
                 * marshalling and set the offset back to the start of
                 * the buffer to re-use it (we could also do a prs_mem_free()
                 * and then re_init on the next start of PDU. Not sure which
                 * is best here.... JRA.
                 */

                prs_switch_type(&p->in_data.data, MARSHALL);
                prs_set_offset(&p->in_data.data, 0);
                return ret;
        }

        return True;
}

/****************************************************************************
 Processes a finished PDU stored in current_in_pdu. The RPC_HEADER has
 already been parsed and stored in p->hdr.
****************************************************************************/

static ssize_t process_complete_pdu(pipes_struct *p)
{
        prs_struct rpc_in;
        size_t data_len = p->in_data.pdu_received_len;
        char *data_p = (char *)&p->in_data.current_in_pdu[0];
        BOOL reply = False;

        if(p->fault_state) {
                DEBUG(10,("process_complete_pdu: pipe %s in fault state.\n",
                        p->name ));
                set_incoming_fault(p);
                setup_fault_pdu(p, NT_STATUS(0x1c010002));
                return (ssize_t)data_len;
        }

        prs_init( &rpc_in, 0, p->mem_ctx, UNMARSHALL);

        /*
         * Ensure we're using the corrent endianness for both the 
         * RPC header flags and the raw data we will be reading from.
         */

        prs_set_endian_data( &rpc_in, p->endian);
        prs_set_endian_data( &p->in_data.data, p->endian);

        prs_give_memory( &rpc_in, data_p, (uint32)data_len, False);

        DEBUG(10,("process_complete_pdu: processing packet type %u\n",
                        (unsigned int)p->hdr.pkt_type ));

        switch (p->hdr.pkt_type) {
                case RPC_BIND:
                case RPC_ALTCONT:
                        /*
                         * We assume that a pipe bind is only in one pdu.
                         */
                        if(pipe_init_outgoing_data(p))
                                reply = api_pipe_bind_req(p, &rpc_in);
                        break;
                case RPC_BINDRESP:
                        /*
                         * We assume that a pipe bind_resp is only in one pdu.
                         */
                        if(pipe_init_outgoing_data(p))
                                reply = api_pipe_bind_auth_resp(p, &rpc_in);
                        break;
                case RPC_REQUEST:
                        reply = process_request_pdu(p, &rpc_in);
                        break;
                default:
                        DEBUG(0,("process_complete_pdu: Unknown rpc type = %u received.\n", (unsigned int)p->hdr.pkt_type ));
                        break;
        }

        /* Reset to little endian. Probably don't need this but it won't hurt. */
        prs_set_endian_data( &p->in_data.data, RPC_LITTLE_ENDIAN);

        if (!reply) {
                DEBUG(3,("process_complete_pdu: DCE/RPC fault sent on pipe %s\n", p->pipe_srv_name));
                set_incoming_fault(p);
                setup_fault_pdu(p, NT_STATUS(0x1c010002));
                prs_mem_free(&rpc_in);
        } else {
                /*
                 * Reset the lengths. We're ready for a new pdu.
                 */
                p->in_data.pdu_needed_len = 0;
                p->in_data.pdu_received_len = 0;
        }

        prs_mem_free(&rpc_in);
        return (ssize_t)data_len;
}

/****************************************************************************
 Accepts incoming data on an rpc pipe. Processes the data in pdu sized units.
****************************************************************************/

static ssize_t process_incoming_data(pipes_struct *p, char *data, size_t n)
{
        size_t data_to_copy = MIN(n, MAX_PDU_FRAG_LEN - p->in_data.pdu_received_len);

        DEBUG(10,("process_incoming_data: Start: pdu_received_len = %u, pdu_needed_len = %u, incoming data = %u\n",
                (unsigned int)p->in_data.pdu_received_len, (unsigned int)p->in_data.pdu_needed_len,
                (unsigned int)n ));

        if(data_to_copy == 0) {
                /*
                 * This is an error - data is being received and there is no
                 * space in the PDU. Free the received data and go into the fault state.
                 */
                DEBUG(0,("process_incoming_data: No space in incoming pdu buffer. Current size = %u \
incoming data size = %u\n", (unsigned int)p->in_data.pdu_received_len, (unsigned int)n ));
                set_incoming_fault(p);
                return -1;
        }

        /*
         * If we have no data already, wait until we get at least a RPC_HEADER_LEN
         * number of bytes before we can do anything.
         */

        if((p->in_data.pdu_needed_len == 0) && (p->in_data.pdu_received_len < RPC_HEADER_LEN)) {
                /*
                 * Always return here. If we have more data then the RPC_HEADER
                 * will be processed the next time around the loop.
                 */
                return fill_rpc_header(p, data, data_to_copy);
        }

        /*
         * At this point we know we have at least an RPC_HEADER_LEN amount of data
         * stored in current_in_pdu.
         */

        /*
         * If pdu_needed_len is zero this is a new pdu. 
         * Unmarshall the header so we know how much more
         * data we need, then loop again.
         */

        if(p->in_data.pdu_needed_len == 0)
                return unmarshall_rpc_header(p);

        /*
         * Ok - at this point we have a valid RPC_HEADER in p->hdr.
         * Keep reading until we have a full pdu.
         */

        data_to_copy = MIN(data_to_copy, p->in_data.pdu_needed_len);

        /*
         * Copy as much of the data as we need into the current_in_pdu buffer.
         */

        memcpy( (char *)&p->in_data.current_in_pdu[p->in_data.pdu_received_len], data, data_to_copy);
        p->in_data.pdu_received_len += data_to_copy;

        /*
         * Do we have a complete PDU ?
         */

        if(p->in_data.pdu_received_len == p->in_data.pdu_needed_len)
                return process_complete_pdu(p);

        DEBUG(10,("process_incoming_data: not a complete PDU yet. pdu_received_len = %u, pdu_needed_len = %u\n",
                (unsigned int)p->in_data.pdu_received_len, (unsigned int)p->in_data.pdu_needed_len ));

        return (ssize_t)data_to_copy;

}

/****************************************************************************
 Accepts incoming data on an rpc pipe.
****************************************************************************/

ssize_t write_to_pipe(pipes_struct *p, char *data, size_t n)
{
        size_t data_left = n;

        DEBUG(6,("write_to_pipe: %x", p->pnum));

        DEBUG(6,(" name: %s open: %s len: %d\n",
                 p->name, BOOLSTR(p->open), (int)n));

        dump_data(50, data, n);

        while(data_left) {
                ssize_t data_used;

                DEBUG(10,("write_to_pipe: data_left = %u\n", (unsigned int)data_left ));

                data_used = process_incoming_data(p, data, data_left);

                DEBUG(10,("write_to_pipe: data_used = %d\n", (int)data_used ));

                if(data_used < 0)
                        return -1;

                data_left -= data_used;
                data += data_used;
        }       

        return n;
}

/****************************************************************************
 Replies to a request to read data from a pipe.

 Headers are interspersed with the data at PDU intervals. By the time
 this function is called, the start of the data could possibly have been
 read by an SMBtrans (file_offset != 0).

 Calling create_rpc_reply() here is a hack. The data should already
 have been prepared into arrays of headers + data stream sections.
****************************************************************************/

ssize_t read_from_pipe(pipes_struct *p, char *data, size_t n)
{
        uint32 pdu_remaining = 0;
        ssize_t data_returned = 0;

        if (!p || !p->open) {
                DEBUG(0,("read_from_pipe: pipe not open\n"));
                return -1;              
        }

        DEBUG(6,("read_from_pipe: %x", p->pnum));

        DEBUG(6,(" name: %s len: %u\n", p->name, (unsigned int)n));

        /*
         * We cannot return more than one PDU length per
         * read request.
         */

        /*
         * This condition should result in the connection being closed.
         * Netapp filers seem to set it to 0xffff which results in domain
         * authentications failing.  Just ignore it so things work.
         */

        if(n > MAX_PDU_FRAG_LEN) {
                DEBUG(5,("read_from_pipe: too large read (%u) requested on \
pipe %s. We can only service %d sized reads.\n", (unsigned int)n, p->name, MAX_PDU_FRAG_LEN ));
        }

        /*
         * Determine if there is still data to send in the
         * pipe PDU buffer. Always send this first. Never
         * send more than is left in the current PDU. The
         * client should send a new read request for a new
         * PDU.
         */

        if((pdu_remaining = p->out_data.current_pdu_len - p->out_data.current_pdu_sent) > 0) {
                data_returned = (ssize_t)MIN(n, pdu_remaining);

                DEBUG(10,("read_from_pipe: %s: current_pdu_len = %u, current_pdu_sent = %u \
returning %d bytes.\n", p->name, (unsigned int)p->out_data.current_pdu_len, 
                        (unsigned int)p->out_data.current_pdu_sent, (int)data_returned));

                memcpy( data, &p->out_data.current_pdu[p->out_data.current_pdu_sent], (size_t)data_returned);
                p->out_data.current_pdu_sent += (uint32)data_returned;
                goto out;
        }

        /*
         * At this point p->current_pdu_len == p->current_pdu_sent (which
         * may of course be zero if this is the first return fragment.
         */

        DEBUG(10,("read_from_pipe: %s: fault_state = %d : data_sent_length \
= %u, prs_offset(&p->out_data.rdata) = %u.\n",
                p->name, (int)p->fault_state, (unsigned int)p->out_data.data_sent_length, (unsigned int)prs_offset(&p->out_data.rdata) ));

        if(p->out_data.data_sent_length >= prs_offset(&p->out_data.rdata)) {
                /*
                 * We have sent all possible data, return 0.
                 */
                data_returned = 0;
                goto out;
        }

        /*
         * We need to create a new PDU from the data left in p->rdata.
         * Create the header/data/footers. This also sets up the fields
         * p->current_pdu_len, p->current_pdu_sent, p->data_sent_length
         * and stores the outgoing PDU in p->current_pdu.
         */

        if(!create_next_pdu(p)) {
                DEBUG(0,("read_from_pipe: %s: create_next_pdu failed.\n", p->name));
                return -1;
        }

        data_returned = MIN(n, p->out_data.current_pdu_len);

        memcpy( data, p->out_data.current_pdu, (size_t)data_returned);
        p->out_data.current_pdu_sent += (uint32)data_returned;

  out:

        return data_returned;
}

/****************************************************************************
 Wait device state on a pipe. Exactly what this is for is unknown...
****************************************************************************/

BOOL wait_rpc_pipe_hnd_state(pipes_struct *p, uint16 priority)
{
        if (p == NULL)
                return False;

        if (p->open) {
                DEBUG(3,("wait_rpc_pipe_hnd_state: Setting pipe wait state priority=%x on pipe (name=%s)\n",
                         priority, p->name));

                p->priority = priority;
                
                return True;
        } 

        DEBUG(3,("wait_rpc_pipe_hnd_state: Error setting pipe wait state priority=%x (name=%s)\n",
                 priority, p->name));
        return False;
}


/****************************************************************************
 Set device state on a pipe. Exactly what this is for is unknown...
****************************************************************************/

BOOL set_rpc_pipe_hnd_state(pipes_struct *p, uint16 device_state)
{
        if (p == NULL)
                return False;

        if (p->open) {
                DEBUG(3,("set_rpc_pipe_hnd_state: Setting pipe device state=%x on pipe (name=%s)\n",
                         device_state, p->name));

                p->device_state = device_state;
                
                return True;
        } 

        DEBUG(3,("set_rpc_pipe_hnd_state: Error setting pipe device state=%x (name=%s)\n",
                 device_state, p->name));
        return False;
}


/****************************************************************************
 Close an rpc pipe.
****************************************************************************/

BOOL close_rpc_pipe_hnd(pipes_struct *p, connection_struct *conn)
{
        if (!p) {
                DEBUG(0,("Invalid pipe in close_rpc_pipe_hnd\n"));
                return False;
        }

        if (strstr(p->name, "spoolss"))
                current_spoolss_pipes_open--;

        prs_mem_free(&p->out_data.rdata);
        prs_mem_free(&p->in_data.data);

        if (p->mem_ctx)
                talloc_destroy(p->mem_ctx);

        /* Free the handles database. */
        close_policy_by_pipe(p);

        bitmap_clear(bmap, p->pnum - pipe_handle_offset);

        pipes_open--;

        DEBUG(4,("closed pipe name %s pnum=%x (pipes_open=%d)\n", 
                 p->name, p->pnum, pipes_open));  

        DLIST_REMOVE(Pipes, p);

        delete_nt_token(&p->pipe_user.nt_user_token);
        safe_free(p->pipe_user.groups);

        ZERO_STRUCTP(p);

        SAFE_FREE(p);

        return True;
}

/****************************************************************************
 Find an rpc pipe given a pipe handle in a buffer and an offset.
****************************************************************************/

pipes_struct *get_rpc_pipe_p(char *buf, int where)
{
        int pnum = SVAL(buf,where);

        if (chain_p)
                return chain_p;

        return get_rpc_pipe(pnum);
}

/****************************************************************************
 Find an rpc pipe given a pipe handle.
****************************************************************************/

pipes_struct *get_rpc_pipe(int pnum)
{
        pipes_struct *p;

        DEBUG(4,("search for pipe pnum=%x\n", pnum));

        for (p=Pipes;p;p=p->next)
                DEBUG(5,("pipe name %s pnum=%x (pipes_open=%d)\n", 
                          p->name, p->pnum, pipes_open));  

        for (p=Pipes;p;p=p->next) {
                if (p->pnum == pnum) {
                        chain_p = p;
                        return p;
                }
        }

        return NULL;
}