proto_detail_work.c

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/*
 *   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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */
 
/**
 * $Id: 1db3139246e97dfa4062dd2e7714b691a1af2d64 $
 * @file proto_detail_work.c
 * @brief Detail handler for files
 *
 * @copyright 2017 The FreeRADIUS server project.
 * @copyright 2017 Alan DeKok (aland@deployingradius.com)
 */
#include <netdb.h>
#include <freeradius-devel/server/protocol.h>
#include <freeradius-devel/server/pair.h>
#include <freeradius-devel/server/main_loop.h>
#include <freeradius-devel/io/application.h>
#include <freeradius-devel/io/listen.h>
#include <freeradius-devel/util/syserror.h>
#include "proto_detail.h"
 
#include <fcntl.h>
#include <sys/stat.h>
 
#ifndef NDEBUG
#if 0
/*
 *      When we want detailed debugging here, without detailed server
 *      debugging.
 */
#define MPRINT DEBUG
#else
#define MPRINT DEBUG3
#endif
#else
// No debugging, just remove the mprint entirely
#define MPRINT(_x, ...)
#endif
 
typedef struct {
        proto_detail_work_thread_t      *parent;                //!< talloc_parent is SLOW!
        fr_time_t                       timestamp;              //!< when we read the entry.
        off_t                           done_offset;            //!< where we're tracking the status
 
        int                             id;                     //!< for retransmission counters
 
        uint8_t                         *packet;                //!< for retransmissions
        size_t                          packet_len;             //!< for retransmissions
 
        fr_retry_t                      retry;                  //!< our retry timers
        fr_event_timer_t const          *ev;                    //!< retransmission timer
        fr_dlist_t                      entry;                  //!< for the retransmission list
} fr_detail_entry_t;
 
static conf_parser_t limit_config[] = {
        { FR_CONF_OFFSET("initial_rtx_time", proto_detail_work_t, retry_config.irt), .dflt = STRINGIFY(2) },
        { FR_CONF_OFFSET("max_rtx_time", proto_detail_work_t, retry_config.mrt), .dflt = STRINGIFY(16) },
 
        /*
         *      Retransmit indefinitely, as v2 and v3 did.
         */
        { FR_CONF_OFFSET("max_rtx_count", proto_detail_work_t, retry_config.mrc), .dflt = STRINGIFY(0) },
        /*
         *      ...again same as v2 and v3.
         */
        { FR_CONF_OFFSET("max_rtx_duration", proto_detail_work_t, retry_config.mrd), .dflt = STRINGIFY(0) },
        { FR_CONF_OFFSET("max_outstanding", proto_detail_work_t, max_outstanding), .dflt = STRINGIFY(1) },
        CONF_PARSER_TERMINATOR
};
 
 
static const conf_parser_t file_listen_config[] = {
        { FR_CONF_OFFSET_FLAGS("filename", CONF_FLAG_REQUIRED, proto_detail_work_t, filename_work ) },
 
        { FR_CONF_OFFSET("track", proto_detail_work_t, track_progress ) },
 
        { FR_CONF_OFFSET("retransmit", proto_detail_work_t, retransmit ), .dflt = "yes" },
 
        { FR_CONF_POINTER("limit", 0, CONF_FLAG_SUBSECTION, NULL), .subcs = (void const *) limit_config },
        CONF_PARSER_TERMINATOR
};
 
static fr_dict_t const *dict_freeradius;
 
extern fr_dict_autoload_t proto_detail_work_dict[];
fr_dict_autoload_t proto_detail_work_dict[] = {
        { .out = &dict_freeradius, .proto = "freeradius" },
 
        { NULL }
};
 
static fr_dict_attr_t const *attr_packet_transmit_counter;
 
extern fr_dict_attr_autoload_t proto_detail_work_dict_attr[];
fr_dict_attr_autoload_t proto_detail_work_dict_attr[] = {
        { .out = &attr_packet_transmit_counter, .name = "Packet-Transmit-Counter", .type = FR_TYPE_UINT32, .dict = &dict_freeradius },
        { NULL }
};
 
/*
 *      All of the decoding is done by proto_detail.c
 */
static int mod_decode(void const *instance, request_t *request, UNUSED uint8_t *const data, UNUSED size_t data_len)
{
 
        proto_detail_work_t const       *inst = talloc_get_type_abort_const(instance, proto_detail_work_t);
        fr_detail_entry_t const         *track = request->async->packet_ctx;
        fr_pair_t *vp;
 
        request->client = inst->client;
 
        request->packet->id = track->id;
        request->reply->id = track->id;
        REQUEST_VERIFY(request);
 
        MEM(pair_update_request(&vp, attr_packet_transmit_counter) >= 0);
        vp->vp_uint32 = track->retry.count;
 
        return 0;
}
 
static fr_event_update_t pause_read[] = {
        FR_EVENT_SUSPEND(fr_event_io_func_t, read),
        { 0 }
};
 
static fr_event_update_t resume_read[] = {
        FR_EVENT_RESUME(fr_event_io_func_t, read),
        { 0 }
};
 
static ssize_t mod_read(fr_listen_t *li, void **packet_ctx, fr_time_t *recv_time_p, uint8_t *buffer, size_t buffer_len, size_t *leftover)
{
        proto_detail_work_t const       *inst = talloc_get_type_abort_const(li->app_io_instance, proto_detail_work_t);
        proto_detail_work_thread_t      *thread = talloc_get_type_abort(li->thread_instance, proto_detail_work_thread_t);
 
        ssize_t                         data_size;
        size_t                          packet_len;
        fr_detail_entry_t               *track;
        uint8_t                         *partial, *end, *next, *p, *record_end;
        uint8_t                         *stopped_search;
        off_t                           done_offset;
 
        fr_assert(*leftover < buffer_len);
        fr_assert(thread->fd >= 0);
        fr_assert(thread->el);
 
        MPRINT("AT COUNT %d offset %ld", thread->count, (long) thread->read_offset);
 
        /*
         *      Process retransmissions before anything else in the
         *      file.
         */
        track = fr_dlist_head(&thread->list);
        if (track) {
                fr_dlist_remove(&thread->list, track);
 
                /*
                 *      Don't over-write "leftover" bytes!
                 */
                if (*leftover) {
                        fr_assert(thread->leftover == 0);
                        if (!thread->leftover_buffer) MEM(thread->leftover_buffer = talloc_array(thread, uint8_t, buffer_len));
 
                        memcpy(thread->leftover_buffer, buffer, *leftover);
                        thread->leftover = *leftover;
                        *leftover = 0;
                }
 
                fr_assert(buffer_len >= track->packet_len);
                memcpy(buffer, track->packet, track->packet_len);
 
                DEBUG("Retrying packet %d (retransmission %u)", track->id, track->retry.count);
                *packet_ctx = track;
                *recv_time_p = track->timestamp;
                return track->packet_len;
        }
 
        /*
         *      If we decide that we're closing, ignore everything
         *      else in the file.  Someone extended the file on us
         *      without locking it first.  So too bad for them.
         */
        if (thread->closing) {
                if (inst->track_progress) thread->read_offset = lseek(thread->fd, 0, SEEK_END);
                return 0;
        }
 
        /*
         *      Once a socket is ready, the network side tries to read
         *      many packets.  So if we want to stop it from reading,
         *      we have to check this ourselves.
         */
        if (thread->outstanding >= inst->max_outstanding) {
                fr_assert(thread->paused);
                return 0;
        }
 
        /*
         *      If we've cached leftover data from the ring buffer,
         *      copy it back.
         */
        if (thread->leftover) {
                fr_assert(*leftover == 0);
                fr_assert(thread->leftover < buffer_len);
 
                memcpy(buffer, thread->leftover_buffer, thread->leftover);
                *leftover = thread->leftover;
                thread->leftover = 0;
        }
 
        /*
         *      Seek to the current read offset.
         */
        (void) lseek(thread->fd, thread->read_offset, SEEK_SET);
 
        /*
         *      There will be "leftover" bytes left over in the buffer
         *      from any previous read.  At the start of the file,
         *      "leftover" will be zero.
         */
        partial = buffer + *leftover;
 
        MPRINT("READ leftover %zd", *leftover);
 
        /*
         *      Try to read as much data as possible.
         */
        if (!thread->eof) {
                size_t room;
 
                room = buffer_len - *leftover;
 
                data_size = read(thread->fd, partial, room);
                if (data_size < 0) {
                        ERROR("proto_detail (%s): Failed reading file %s: %s",
                              thread->name, thread->filename_work, fr_syserror(errno));
                        return -1;
                }
 
                MPRINT("GOT %zd bytes", data_size);
 
                /*
                 *      Remember the read offset, and whether we got EOF.
                 */
                thread->read_offset = lseek(thread->fd, 0, SEEK_CUR);
 
                /*
                 *      Only set EOF if there's no more data in the buffer to manage.
                 */
                thread->eof = (data_size == 0) || (thread->read_offset == thread->file_size) || ((size_t) data_size < room);
                if (thread->eof) {
                        MPRINT("Set EOF data_size %ld vs room %ld", data_size, room);
                        MPRINT("Set EOF read %ld vs file %ld", (long) thread->read_offset, (long) thread->file_size);
                }
                end = partial + data_size;
 
        } else {
                MPRINT("READ UNTIL EOF");
                /*
                 *      We didn't read any more data from the file,
                 *      but there should be data left in the buffer.
                 */
                fr_assert(*leftover > 0);
                end = buffer + *leftover;
        }
 
redo:
        next = NULL;
        stopped_search = end;
 
        /*
         *      Look for "end of record" marker, starting from the
         *      beginning of the buffer.
         *
         *      Note that all of the data MUST be printable, and raw
         *      LFs are forbidden in attribute contents.
         */
        fr_assert((buffer + thread->last_search) <= end);
 
        MPRINT("Starting search from offset %ld", thread->last_search);
 
        p = buffer + thread->last_search;
        while (p < end) {
                if (p[0] != '\n') {
                        p++;
                        continue;
                }
                if ((p + 1) == end) {
                        /*
                         *      Remember the last LF, so if the next
                         *      read starts with a LF, we can find the
                         *      end of record marker.
                         */
                        stopped_search = p;
                        break; /* no more data */
                }
 
                if (p[1] == '\n') {
                        p[0] = '\0';
                        p[1] = '\0';
                        next = p + 2;
                        stopped_search = next;
                        break;
                }
 
                /*
                 *      If we're not at EOF, and we're not at end of
                 *      record, every line MUST have a leading tab.
                 */
                if (p[1] != '\t') {
                        ERROR("proto_detail (%s): Malformed line found at offset %zu in file %s",
                              thread->name, (size_t)((p - buffer) + thread->header_offset),
                              thread->filename_work);
                        return -1;
                }
 
                /*
                 *      Smash the \n with zero, so that each line can
                 *      be parsed individually.
                 */
                p[0] = '\0';
 
                /*
                 *      Skip the \n\t
                 */
                if ((p + 2) >= end) {
                        stopped_search = p;
                        break;
                }
 
                p += 2;
 
                /*
                 *      Skip attribute name
                 */
                while ((p < end) && !isspace((uint8_t) *p)) p++;
 
                /*
                 *      Not enough room for " = ", skip this sanity
                 *      check, and just search for a \n on the next
                 *      round through the loop.
                 */
                if ((end - p) < 3) {
                        stopped_search = p;
                        break;
                }
 
                /*
                 *      Check for " = ".  If the line doesn't contain
                 *      this, it's malformed.
                 */
                if (memcmp(p, " = ", 3) != 0) {
                        ERROR("proto_detail (%s): Malformed line found at offset %zu: %.*s of file %s",
                              thread->name,
                              (size_t)((p - buffer) + thread->header_offset), (int) (end - p), p,
                              thread->filename_work);
                        return -1;
                }
 
                /*
                 *      Skip the " = ", and go back to the top of the
                 *      loop where we check for the next \n.
                 */
                p += 3;
        }
 
        thread->last_search = (stopped_search - buffer);
 
        /*
         *      If there is a next record, remember how large this
         *      record is, and update "leftover" bytes.
         */
        if (next) {
                packet_len = next - buffer;
                *leftover = end - next;
 
                MPRINT("FOUND next at %zd, leftover is %zd", packet_len, *leftover);
 
        } else if (!thread->eof) {
                if ((size_t) (end - buffer) == buffer_len) {
                        ERROR("proto_detail (%s): Too large entry (>%d bytes) found at offset %zu: %.*s of file %s",
                              thread->name, (int) buffer_len,
                              (size_t)((p - buffer) + thread->header_offset), (int) (end - p), p,
                              thread->filename_work);
                        return -1;
                }
 
                /*
                 *      We're not at EOF, and there is no "next"
                 *      entry.  Remember all of the leftover data in
                 *      the buffer, and ask the caller to call us when
                 *      there's more data.
                 */
                *leftover = end - buffer;
                MPRINT("Not at EOF, and no next.  Leftover is %zd", *leftover);
                return 0;
 
        } else {
                /*
                 *      Else we're at EOF, it's OK to not have an "end
                 *      of record" marker.  We just eat all of the
                 *      remaining data.
                 */
                packet_len = end - buffer;
                *leftover = 0;
 
                MPRINT("NO end of record, but at EOF, found %zd leftover is 0", packet_len);
        }
 
        /*
         *      Too big?  Ignore it.
         *
         *      @todo - skip the record, using memmove() etc.
         */
        if (packet_len > inst->parent->max_packet_size) {
                DEBUG("Ignoring 'too large' entry at offset %zu of %s",
                      (size_t) thread->header_offset, thread->filename_work);
                DEBUG("Entry size %lu is greater than allowed maximum %u",
                      packet_len, inst->parent->max_packet_size);
        skip_record:
                MPRINT("Skipping record");
                if (next) {
                        memmove(buffer, next, (end - next));
                        data_size = (end - next);
                        *leftover = 0;
                        end = buffer + data_size;
                        thread->last_search = 0;
 
                        /*
                         *      No more data, we're done.
                         */
                        if (end == buffer) return 0;
                        goto redo;
                }
 
                fr_assert(*leftover == 0);
                goto done;
        }
 
        /*
         *      Search for the "Timestamp" attribute.  We overload
         *      that to track which entries have been used.
         */
        record_end = buffer + packet_len;
        p = buffer;
        done_offset = 0;
 
        while (p < record_end) {
                if (*p != '\0') {
                        p++;
                        continue;
                }
 
                p++;
                if (p == record_end) break;
 
                if (((record_end - p) >= 5) &&
                    (memcmp(p, "\tDone", 5) == 0)) {
                        goto skip_record;
                }
 
                if (((record_end - p) > 10) &&
                    (memcmp(p, "\tTimestamp", 10) == 0)) {
                        p++;
                        done_offset = thread->header_offset + (p - buffer);
                }
        }
 
        /*
         *      Allocate the tracking entry.
         */
        track = talloc_zero(thread, fr_detail_entry_t);
        track->parent = thread;
        track->timestamp = fr_time();
        track->id = thread->count++;
 
        track->done_offset = done_offset;
        if (inst->retransmit) {
                track->packet = talloc_memdup(track, buffer, packet_len);
                track->packet_len = packet_len;
        }
 
        /*
         *      We've read one more packet.
         */
        thread->header_offset += packet_len;
 
        *packet_ctx = track;
        *recv_time_p = track->timestamp;
 
done:
        /*
         *      If we're at EOF, mark us as "closing".
         */
        if (thread->eof) {
                fr_assert(!thread->closing);
                thread->closing = (*leftover == 0);
                MPRINT("AT EOF, BUT CLOSING %d", thread->closing);
        }
 
        thread->outstanding++;
 
        /*
         *      Pause reading until such time as we need more packets.
         */
        if (!thread->paused && (thread->outstanding >= inst->max_outstanding)) {
                (void) fr_event_filter_update(thread->el, thread->fd, FR_EVENT_FILTER_IO, pause_read);
                thread->paused = true;
 
                /*
                 *      Back up so that read() knows there's more data.
                 */
                if (*leftover) (void) lseek(thread->fd, thread->read_offset - 1, SEEK_SET);
        }
 
        /*
         *      Next time, start searching from the start of the
         *      buffer.
         */
        thread->last_search = 0;
 
        MPRINT("Returning NUM %u - %.*s", thread->outstanding, (int) packet_len, buffer);
        return packet_len;
}
 
 
static void work_retransmit(UNUSED fr_event_list_t *el, UNUSED fr_time_t now, void *uctx)
{
        fr_detail_entry_t               *track = talloc_get_type_abort(uctx, fr_detail_entry_t);
        proto_detail_work_thread_t      *thread = track->parent;
 
        DEBUG("%s - retransmitting packet %d", thread->name, track->id);
 
        fr_dlist_insert_tail(&thread->list, track);
 
        if (thread->paused && (thread->outstanding < thread->inst->max_outstanding)) {
                (void) fr_event_filter_update(thread->el, thread->fd, FR_EVENT_FILTER_IO, resume_read);
                thread->paused = false;
        }
 
        fr_assert(thread->fd >= 0);
 
        /*
         *      Seek to the START of the file, so that the FD will
         *      always return ready.
         *
         *      The mod_read() function will take care of seeking to
         *      the correct read offset.
         */
        (void) lseek(thread->fd, 0, SEEK_SET);
 
#ifdef __linux__
        fr_network_listen_read(thread->nr, thread->listen);
#endif
}
 
static ssize_t mod_write(fr_listen_t *li, void *packet_ctx, UNUSED fr_time_t request_time,
                         uint8_t *buffer, size_t buffer_len, UNUSED size_t written)
{
        proto_detail_work_t const       *inst = talloc_get_type_abort_const(li->app_io_instance, proto_detail_work_t);
        proto_detail_work_thread_t      *thread = talloc_get_type_abort(li->thread_instance, proto_detail_work_thread_t);
        fr_detail_entry_t               *track = packet_ctx;
 
        if (buffer_len < 1) return -1;
 
        fr_assert(thread->outstanding > 0);
        fr_assert(thread->fd >= 0);
 
        if (!buffer[0]) {
                if (!inst->retransmit) goto mark_done;
 
                if (fr_time_eq(track->retry.start, fr_time_wrap(0))) {
                        fr_retry_init(&track->retry, fr_time(), &inst->retry_config);
                } else {
                        fr_retry_state_t state;
 
                        state = fr_retry_next(&track->retry, fr_time());
                        if (state == FR_RETRY_MRC) {
                                DEBUG("%s - packet %d failed after %u retransmissions",
                                      thread->name, track->id, track->retry.count);
                                goto fail;
 
                        }
 
                        if (state == FR_RETRY_MRD) {
                                DEBUG("%s - packet %d failed after %u seconds",
                                      thread->name, track->id,
                                      (unsigned int) fr_time_delta_to_sec(inst->retry_config.mrd));
                                goto fail;
                        }
                }
 
                DEBUG("%s - packet %d failed during processing.  Will retransmit in %.6fs",
                      thread->name, track->id, fr_time_delta_unwrap(track->retry.rt) / (double)NSEC);
 
                if (fr_event_timer_at(thread, thread->el, &track->ev,
                                      track->retry.next, work_retransmit, track) < 0) {
                        ERROR("%s - Failed inserting retransmission timeout", thread->name);
                fail:
                        if (inst->track_progress && (track->done_offset > 0)) goto mark_done;
                        goto free_track;
                }
 
                if (!thread->paused && (thread->outstanding >= inst->max_outstanding)) {
                        (void) fr_event_filter_update(thread->el, thread->fd, FR_EVENT_FILTER_IO, pause_read);
                        thread->paused = true;
                }
 
                return 1;
 
        } else if (inst->track_progress && (track->done_offset > 0)) {
        mark_done:
                /*
                 *      Seek to the entry, mark it as done, and then seek to
                 *      the point in the file where we were reading from.
                 */
                (void) lseek(thread->fd, track->done_offset, SEEK_SET);
                if (write(thread->fd, "Done", 4) < 0) {
                        ERROR("%s - Failed marking entry as done: %s", thread->name, fr_syserror(errno));
                }
                (void) lseek(thread->fd, thread->read_offset, SEEK_SET);
        }
 
free_track:
        thread->outstanding--;
 
        /*
         *      If we need to read some more packet, let's do so.
         */
        if (thread->paused && (thread->outstanding < inst->max_outstanding)) {
                (void) fr_event_filter_update(thread->el, thread->fd, FR_EVENT_FILTER_IO, resume_read);
                thread->paused = false;
 
                /*
                 *      And seek to the start of the file, so that the
                 *      reader gets activated again.  The reader will
                 *      lseek() to the read offset, so this seek is fine.
                 */
                (void) lseek(thread->fd, 0, SEEK_SET);
        }
 
        /*
         *      @todo - add a used / free pool for these
         */
        talloc_free(track);
 
        /*
         *      Close the socket if we're at EOF, and there are no
         *      outstanding replies to deal with.
         */
        if (thread->closing && !thread->outstanding) {
                MPRINT("WRITE ASKED TO CLOSE");
                return 0;
        }
 
        MPRINT("WRITE RETURN B %ld", buffer_len);
        return buffer_len;
}
 
/** Open a detail listener
 *
 */
static int mod_open(fr_listen_t *li)
{
        proto_detail_work_t const       *inst = talloc_get_type_abort_const(li->app_io_instance, proto_detail_work_t);
        proto_detail_work_thread_t      *thread = talloc_get_type_abort(li->thread_instance, proto_detail_work_thread_t);
 
        fr_dlist_init(&thread->list, fr_detail_entry_t, entry);
 
        /*
         *      Open the file if we haven't already been given one.
         */
        if (thread->fd < 0) {
                thread->filename_work = talloc_strdup(inst, inst->filename_work);
 
                li->fd = thread->fd = open(thread->filename_work, inst->mode);
                if (thread->fd < 0) {
                        cf_log_err(inst->cs, "Failed opening %s: %s", thread->filename_work, fr_syserror(errno));
                        return -1;
                }
        }
 
        /*
         *      If we're tracking progress, learn where the EOF is.
         */
        if (inst->track_progress) {
                struct stat buf;
 
                if (fstat(thread->fd, &buf) < 0) {
                        cf_log_err(inst->cs, "Failed examining %s: %s", thread->filename_work, fr_syserror(errno));
                        return -1;
                }
 
                thread->file_size = buf.st_size;
        } else {
                /*
                 *      Avoid triggering erroneous EOF.
                 */
                thread->file_size = 1;
        }
 
        fr_assert(thread->name == NULL);
        fr_assert(thread->filename_work != NULL);
        thread->name = talloc_typed_asprintf(thread, "detail_work reading file %s", thread->filename_work);
 
        /*
         *      Linux doesn't like us adding write callbacks for FDs
         *      which reference files.  Since the callback is only
         *      used when the FD blocks, and files don't (mostly)
         *      block, we just mark this read-only.
         *
         *      The code in src/lib/io/network.c will call the
         *      mod_write() callback on any write, even if the
         *      listener is marked "read_only"
         */
        li->no_write_callback = true;
 
        return 0;
}
 
 
static int mod_close_internal(proto_detail_work_thread_t *thread)
{
        proto_detail_work_t const       *inst = talloc_get_type_abort_const(thread->inst, proto_detail_work_t);
 
        /*
         *      One less worker...  we check for "0" because of the
         *      hacks in proto_detail which let us start up with
         *      "transport = work" for debugging purposes.
         */
        if (thread->file_parent) {
                pthread_mutex_lock(&thread->file_parent->worker_mutex);
                if (thread->file_parent->num_workers > 0) thread->file_parent->num_workers--;
                pthread_mutex_unlock(&thread->file_parent->worker_mutex);
        }
 
        DEBUG("Closing %sdetail worker file %s", thread->outstanding == 0 ? "and deleting " : "", thread->name);
 
#ifdef NOTE_REVOKE
        fr_event_fd_delete(thread->el, thread->fd, FR_EVENT_FILTER_VNODE);
#endif
        fr_event_fd_delete(thread->el, thread->fd, FR_EVENT_FILTER_IO);
 
        if (thread->outstanding == 0) unlink(thread->filename_work);
 
        close(thread->fd);
        thread->fd = -1;
 
        /*
         *      If we've been spawned from proto_detail_file, clean
         *      ourselves up, including our listener.
         */
        if (thread->listen) {
                talloc_free(thread->listen);
        }
 
        if (inst->parent->exit_when_done) {
                INFO("Done reading detail files, process will now exit");
 
                /*
                 *      The least hacky way of signalling that the server
                 *      should exit.  This is an almost identical code
                 *      path as receiving a SIGTERM.
                 */
                main_loop_signal_raise(RADIUS_SIGNAL_SELF_TERM);
        }
 
        return 0;
}
 
 
/** Close  a detail listener
 *
 */
static int mod_close(fr_listen_t *li)
{
        proto_detail_work_thread_t *thread = talloc_get_type_abort(li->thread_instance, proto_detail_work_thread_t);
 
        return mod_close_internal(thread);
}
 
#ifdef NOTE_REVOKE
static void mod_revoke(UNUSED fr_event_list_t *el, UNUSED int fd, UNUSED int flags, void *uctx)
{
        proto_detail_work_thread_t *thread = talloc_get_type_abort(uctx, proto_detail_work_thread_t);
 
        /*
         *      The underlying file system is gone.  Stop reading the
         *      file, destroy all of the IO handlers, and delete everything.
         */
        DEBUG("Detail worker %s had file system unmounted.  Stopping.", thread->name);
        mod_close_internal(thread);
}
#endif
 
 
/** Set the event list for a new IO instance
 *
 * @param[in] li the listener
 * @param[in] el the event list
 * @param[in] nr context from the network side
 */
static void mod_event_list_set(fr_listen_t *li, fr_event_list_t *el, void *nr)
{
        proto_detail_work_thread_t *thread = talloc_get_type_abort(li->thread_instance, proto_detail_work_thread_t);
 
#ifdef NOTE_REVOKE
        fr_event_vnode_func_t funcs;
 
        memset(&funcs, 0, sizeof(funcs));
        funcs.revoke = mod_revoke;
 
        if (fr_event_filter_insert(thread, NULL, el, thread->fd, FR_EVENT_FILTER_VNODE, &funcs, NULL, thread) < 0) {
                WARN("Failed to add event watching for unmounted file system");
        }
#endif
 
        thread->el = el;
        thread->nr = nr;
}
 
 
static char const *mod_name(fr_listen_t *li)
 
{       proto_detail_work_thread_t *thread = talloc_get_type_abort(li->thread_instance, proto_detail_work_thread_t);
 
        return thread->name;
}
 
static int mod_instantiate(module_inst_ctx_t const *mctx)
{
        proto_detail_work_t *inst = talloc_get_type_abort(mctx->inst->data, proto_detail_work_t);
        fr_client_t *client;
 
        client = inst->client = talloc_zero(inst, fr_client_t);
        if (!inst->client) return 0;
 
        client->ipaddr.af = AF_INET;
        client->ipaddr.addr.v4.s_addr = htonl(INADDR_NONE);
        client->src_ipaddr = client->ipaddr;
 
        client->longname = client->shortname = client->secret = inst->filename;
        client->nas_type = talloc_strdup(client, "other");
 
        return 0;
}
 
static int mod_bootstrap(module_inst_ctx_t const *mctx)
{
        proto_detail_work_t     *inst = talloc_get_type_abort(mctx->inst->data, proto_detail_work_t);
        CONF_SECTION            *cs = mctx->inst->conf;
        dl_module_inst_t const  *dl_inst;
 
        /*
         *      Find the dl_module_inst_t holding our instance data
         *      so we can find out what the parent of our instance
         *      was.
         */
        dl_inst = dl_module_instance_by_data(mctx->inst->data);
        fr_assert(dl_inst);
 
        inst->parent = talloc_get_type_abort(dl_inst->parent->data, proto_detail_t);
        inst->cs = cs;
 
        if (inst->track_progress) {
                inst->mode = O_RDWR;
        } else {
                inst->mode = O_RDONLY;
        }
 
        if (inst->retransmit) {
                FR_TIME_DELTA_BOUND_CHECK("limit.initial_rtx_time", inst->retry_config.irt, >=, fr_time_delta_from_sec(1));
                FR_TIME_DELTA_BOUND_CHECK("limit.initial_rtx_time", inst->retry_config.irt, <=, fr_time_delta_from_sec(60));
 
                /*
                 *      If you need more than this, just set it to
                 *      "0", and check Packet-Transmit-Count manually.
                 */
                FR_INTEGER_BOUND_CHECK("limit.max_rtx_count", inst->retry_config.mrc, <=, 20);
                FR_TIME_DELTA_BOUND_CHECK("limit.max_rtx_duration", inst->retry_config.mrd, <=, fr_time_delta_from_sec(600));
 
                /*
                 *      This is a reasonable value.
                 */
                FR_TIME_DELTA_BOUND_CHECK("limit.max_rtx_timer", inst->retry_config.mrt, <=, fr_time_delta_from_sec(30));
        }
 
        FR_INTEGER_BOUND_CHECK("limit.max_outstanding", inst->max_outstanding, >=, 1);
 
        return 0;
}
 
 
/** Private interface for use by proto_detail_file
 *
 */
extern fr_app_io_t proto_detail_work;
fr_app_io_t proto_detail_work = {
        .common = {
                .magic                  = MODULE_MAGIC_INIT,
                .name                   = "detail_work",
                .config                 = file_listen_config,
                .inst_size              = sizeof(proto_detail_work_t),
                .thread_inst_size       = sizeof(proto_detail_work_thread_t),
                .bootstrap              = mod_bootstrap,
                .instantiate            = mod_instantiate
        },
        .default_message_size   = 65536,
        .default_reply_size     = 32,
 
        .open                   = mod_open,
        .close                  = mod_close,
        .read                   = mod_read,
        .decode                 = mod_decode,
        .write                  = mod_write,
        .event_list_set         = mod_event_list_set,
        .get_name               = mod_name,
};