request.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: 6d0a283701e1c804cb11c364277b8d74e1468f7d $
 *
 * @brief Functions for allocating requests and storing internal data in them.
 * @file src/lib/server/request.c
 *
 * @copyright 2015 The FreeRADIUS server project
 */
RCSID("$Id: 6d0a283701e1c804cb11c364277b8d74e1468f7d $")
 
#include <freeradius-devel/server/request.h>
#include <freeradius-devel/server/request_data.h>
#include <freeradius-devel/unlang/interpret.h>
 
#include <freeradius-devel/util/debug.h>
#include <freeradius-devel/util/atexit.h>
 
static fr_dict_t const *dict_freeradius;
 
extern fr_dict_autoload_t request_dict[];
fr_dict_autoload_t request_dict[] = {
        { .out = &dict_freeradius, .proto = "freeradius" },
        { NULL }
};
 
fr_dict_attr_t const *request_attr_root;
fr_dict_attr_t const *request_attr_request;
fr_dict_attr_t const *request_attr_reply;
fr_dict_attr_t const *request_attr_control;
fr_dict_attr_t const *request_attr_state;
fr_dict_attr_t const *request_attr_local;
 
extern fr_dict_attr_autoload_t request_dict_attr[];
fr_dict_attr_autoload_t request_dict_attr[] = {
        { .out = &request_attr_root, .name = "root", .type = FR_TYPE_GROUP, .dict = &dict_freeradius },
        { .out = &request_attr_request, .name = "request", .type = FR_TYPE_GROUP, .dict = &dict_freeradius },
        { .out = &request_attr_reply, .name = "reply", .type = FR_TYPE_GROUP, .dict = &dict_freeradius },
        { .out = &request_attr_control, .name = "control", .type = FR_TYPE_GROUP, .dict = &dict_freeradius },
        { .out = &request_attr_state, .name = "session-state", .type = FR_TYPE_GROUP, .dict = &dict_freeradius },
        { .out = &request_attr_local, .name = "local-variables", .type = FR_TYPE_GROUP, .dict = &dict_freeradius },
        { NULL }
};
 
#ifndef NDEBUG
static int _state_ctx_free(fr_pair_t *state)
{
        DEBUG4("state-ctx %p freed", state);
 
        return 0;
}
#endif
 
static inline void CC_HINT(always_inline) request_log_init_orphan(request_t *request)
{
        /*
         *      These may be changed later by request_pre_handler
         */
        request->log.lvl = fr_debug_lvl;        /* Default to global debug level */
        if (!request->log.dst) {
                request->log.dst = talloc_zero(request, log_dst_t);
        } else {
                memset(request->log.dst, 0, sizeof(*request->log.dst));
        }
        request->log.dst->func = vlog_request;
        request->log.dst->uctx = &default_log;
        request->log.dst->lvl = fr_debug_lvl;
}
 
/** Prepend another logging destination to the list.
 *
 
 * @param request       the request
 * @param log_dst       the logging destination
 * @param lvl           the new request debug lvl
 */
void request_log_prepend(request_t *request, fr_log_t *log_dst, fr_log_lvl_t lvl)
{
        log_dst_t *dst;
 
        if (lvl == L_DBG_LVL_DISABLE) {
                while (request->log.dst) {
                        dst = request->log.dst->next;
                        talloc_free(request->log.dst);
                        request->log.dst = dst;
                }
                request->log.lvl = L_DBG_LVL_OFF;
                return;
        }
 
        /*
         *      Remove a particular log destination.
         */
        if (lvl == L_DBG_LVL_OFF) {
                log_dst_t **last;
 
                last = &request->log.dst;
                while (*last) {
                        dst = *last;
                        if (((fr_log_t *)dst->uctx)->parent == log_dst) {
                                *last = dst->next;
                                talloc_free(dst);
                                if (!request->log.dst) request->log.lvl = L_DBG_LVL_OFF;
                                return;
                        }
 
                        last = &(dst->next);
                }
 
                return;
        }
 
        /*
         *      Change the debug level of an existing destination.
         */
        for (dst = request->log.dst; dst != NULL; dst = dst->next) {
                if (((fr_log_t *)dst->uctx)->parent == log_dst) {
                        dst->lvl = lvl;
                        if (lvl > request->log.lvl) request->log.lvl = lvl;
                        return;
                }
        }
 
        /*
         *      Not found, add a new log destination.
         */
        MEM(dst = talloc_zero(request, log_dst_t));
 
        dst->func = vlog_request;
        dst->uctx = log_dst;
 
        dst->lvl = lvl;
        if (lvl > request->log.lvl) request->log.lvl = lvl;
        dst->next = request->log.dst;
 
        request->log.dst = dst;
}
 
static inline void CC_HINT(always_inline) request_log_init_child(request_t *child, request_t const *parent)
{
        /*
         *      Copy debug information.
         */
        memcpy(&(child->log), &(parent->log), sizeof(child->log));
        child->log.indent.unlang = 0;   /* Apart from the indent which we reset */
        child->log.indent.module = 0;   /* Apart from the indent which we reset */
        child->log.lvl = parent->log.lvl;
}
 
static inline void CC_HINT(always_inline) request_log_init_detachable(request_t *child, request_t const *parent)
{
        request_log_init_child(child, parent);
 
        /*
         *      Ensure that we use our own version of the logging
         *      information, and not the original request one.
         */
        child->log.dst = talloc_zero(child, log_dst_t);
        memcpy(child->log.dst, parent->log.dst, sizeof(*child->log.dst));
}
 
static inline CC_HINT(always_inline) int request_detachable_init(request_t *child, request_t *parent)
{
        /*
         *      Associate the child with the parent, using the child's
         *      pointer as a unique identifier.  Free it if the parent
         *      goes away, but don't persist it across
         *      challenge-response boundaries.
         */
        if (request_data_talloc_add(parent, child, 0, request_t, child, true, true, false) < 0) return -1;
 
        return 0;
}
 
static inline CC_HINT(always_inline) int request_child_init(request_t *child, request_t *parent)
{
        child->number = parent->child_number++;
        if (!child->proto_dict) {
                child->proto_dict = parent->proto_dict;
                child->local_dict = parent->proto_dict;
        }
 
        if ((parent->seq_start == 0) || (parent->number == parent->seq_start)) {
                child->name = talloc_typed_asprintf(child, "%s.%" PRIu64, parent->name, child->number);
        } else {
                child->name = talloc_typed_asprintf(child, "(%s,%" PRIu64 ").%" PRIu64,
                                                   parent->name, parent->seq_start, child->number);
        }
        child->seq_start = 0;   /* children always start with their own sequence */
        child->parent = parent;
 
        /*
         *      For new server support.
         *
         *      FIXME: Key instead off of a "virtual server" data structure.
         *
         *      FIXME: Permit different servers for inner && outer sessions?
         */
        child->packet = fr_packet_alloc(child, true);
        if (!child->packet) {
                talloc_free(child);
                return -1;
        }
 
        child->reply = fr_packet_alloc(child, false);
        if (!child->reply) {
                talloc_free(child);
                return -1;
        }
 
        return 0;
}
 
/** Setup logging and other fields for a request
 *
 * @param[in] file              the request was allocated in.
 * @param[in] line              the request was allocated on.
 * @param[in] request           to (re)-initialise.
 * @param[in] type              of request to initialise.
 * @param[in] args              Other optional arguments.
 */
int _request_init(char const *file, int line,
                  request_t *request, request_type_t type,
                  request_init_args_t const *args)
{
        fr_dict_t const *dict;
 
        /*
         *      Sanity checks for different requests types
         */
        switch (type) {
        case REQUEST_TYPE_EXTERNAL:
                fr_assert(args);
 
                if (!fr_cond_assert_msg(!args->parent, "External requests must NOT have a parent")) return -1;
 
                fr_assert(args->namespace);
 
                dict = args->namespace;
                break;
 
        case REQUEST_TYPE_INTERNAL:
                if (!args || !args->namespace) {
                        dict = fr_dict_internal();
                } else {
                        dict = args->namespace;
                }
                break;
 
        case REQUEST_TYPE_DETACHED:
                fr_assert_fail("Detached requests should start as type == REQUEST_TYPE_INTERNAL, "
                               "args->detachable and be detached later");
                return -1;
 
        /* Quiet GCC */
        default:
                fr_assert_fail("Invalid request type");
                return -1;
        }
 
        *request = (request_t){
#ifndef NDEBUG
                .magic = REQUEST_MAGIC,
#endif
                .type = type,
                .master_state = REQUEST_ACTIVE,
                .proto_dict = fr_dict_proto_dict(dict),
                .local_dict = dict,
                .component = "<pre-core>",
                .flags = {
                        .detachable = args && args->detachable,
                },
                .alloc_file = file,
                .alloc_line = line
        };
 
 
        /*
         *      Initialise the stack
         */
        MEM(request->stack = unlang_interpret_stack_alloc(request));
 
        /*
         *      Initialise the request data list
         */
        request_data_list_init(&request->data);
 
        {
                fr_pair_t *vp = NULL, *pair_root;
 
                /*
                 *      Alloc the pair root this is a
                 *      special pair which does not
                 *      free its children when it is
                 *      freed.
                 */
                pair_root = fr_pair_root_afrom_da(request, request_attr_root);
                if (unlikely(!pair_root)) return -1;
                request->pair_root = pair_root;
 
                /*
                 *      Copy all the pair lists over into
                 *      the request.  We then check for
                 *      the any uninitialised lists and
                 *      create them locally.
                 */
                if (args) memcpy(&request->pair_list, &args->pair_list, sizeof(request->pair_list));
 
#define list_init(_ctx, _list) \
        do { \
                vp = fr_pair_afrom_da(_ctx, request_attr_##_list); \
                if (unlikely(!vp)) { \
                        talloc_free(pair_root); \
                        memset(&request->pair_list, 0, sizeof(request->pair_list)); \
                        return -1; \
                } \
                fr_pair_append(&pair_root->children, vp); \
                request->pair_list._list = vp; \
        } while(0)
 
                if (!request->pair_list.request) list_init(request->pair_root, request);
                if (!request->pair_list.reply) list_init(request->pair_root, reply);
                if (!request->pair_list.control) list_init(request->pair_root, control);
                if (!request->pair_list.local) list_init(request->pair_root, local);
                if (!request->pair_list.state) {
                        list_init(NULL, state);
#ifndef NDEBUG
                        talloc_set_destructor(request->pair_list.state, _state_ctx_free);
#endif
                }
        }
 
        /*
         *      Initialise packets and additional
         *      fields if this is going to be a
         *      child request.
         */
        if (args && args->parent) {
                if (request_child_init(request, args->parent) < 0) return -1;
 
                if (args->detachable) {
                        if (request_detachable_init(request, args->parent) < 0) return -1;
                        request_log_init_detachable(request, args->parent);
                } else {
                        request_log_init_child(request, args->parent);
                }
        } else {
                request_log_init_orphan(request);
        }
 
        /*
         *      This is only used by src/lib/io/worker.c
         */
        fr_dlist_entry_init(&request->listen_entry);
 
        return 0;
}
 
/** Callback for slabs to deinitialise the request
 *
 * Does not need to be called for local requests.
 *
 * @param[in] request           deinitialise
 * @return
 *      - 0 in the request was deinitialised.
 *      - -1 if the request is in an unexpected state.
 */
int request_slab_deinit(request_t *request)
{
        fr_assert_msg(!fr_timer_armed(request->timeout),
                      "alloced %s:%i: %s still in the  timeout sublist",
                      request->alloc_file,
                      request->alloc_line,
                      request->name ? request->name : "(null)");
        fr_assert_msg(!fr_heap_entry_inserted(request->runnable),
                      "alloced %s:%i: %s still in the runnable heap ID %i",
                      request->alloc_file,
                      request->alloc_line,
                      request->name ? request->name : "(null)", request->runnable);
 
        RDEBUG3("Request deinitialising (%p)", request);
 
        /*
         *      state_ctx is parented separately.
         */
        if (request->session_state_ctx) TALLOC_FREE(request->session_state_ctx);
 
        /*
         *      Zero out everything.
         */
        memset(request, 0, sizeof(*request));
 
#ifndef NDEBUG
        request->component = "free_list";
        request->runnable = FR_HEAP_INDEX_INVALID;
        request->magic = 0x01020304;    /* set the request to be nonsense */
#endif
 
        return 0;
}
 
static inline CC_HINT(always_inline) request_t *request_alloc_pool(TALLOC_CTX *ctx)
{
        request_t *request;
 
        /*
         *      Only allocate requests in the NULL
         *      ctx.  There's no scenario where it's
         *      appropriate to allocate them in a
         *      pool, and using a strict talloc
         *      hierarchy means that child requests
         *      cannot be returned to a free list
         *      and would have to be freed.
         */
        MEM(request = talloc_pooled_object(ctx, request_t,
                                           REQUEST_POOL_HEADERS,
                                           REQUEST_POOL_SIZE));
        fr_assert(ctx != request);
 
        return request;
}
 
static int _request_local_free(request_t *request)
{
        RDEBUG4("Local request freed (%p)", request);
 
        /*
         *      Ensure anything that might reference the request is
         *      freed before it is.
         */
        talloc_free_children(request);
 
        /*
         *      state_ctx is parented separately.
         *
         *      The reason why it's OK to do this, is if the state attributes
         *      need to persist across requests, they will already have been
         *      moved to a fr_state_entry_t, with the state pointers in the
         *      request being set to NULL, before the request is freed/
         *
         *      Note also that we do NOT call TALLOC_FREE(), which
         *      sets state_ctx=NULL.  We don't control the order in
         *      which talloc frees the children.  And the parents
         *      state_ctx pointer needs to stick around so that all of
         *      the children can check it.
         *
         *      If this assertion hits, it means that someone didn't
         *      call fr_state_store_in_parent()
         */
        if (request->session_state_ctx) {
                fr_assert(!request->parent || (request->session_state_ctx != request->parent->session_state_ctx));
 
                talloc_free(request->session_state_ctx);
        }
 
#ifndef NDEBUG
        request->magic = 0x01020304;    /* set the request to be nonsense */
#endif
 
        return 0;
}
 
/** Allocate a request that's not in the free list
 *
 * This can be useful if modules need a persistent request for their own purposes
 * which needs to be outside of the normal free list, so that it can be freed
 * when the module requires, not when the thread destructor runs.
 */
request_t *_request_local_alloc(char const *file, int line, TALLOC_CTX *ctx,
                                request_type_t type, request_init_args_t const *args)
{
        request_t *request;
 
        request = request_alloc_pool(ctx);
        if (_request_init(file, line, request, type, args) < 0) return NULL;
 
        talloc_set_destructor(request, _request_local_free);
 
        return request;
}
 
/** Replace the session_state_ctx with a new one.
 *
 *  NOTHING should rewrite request->session_state_ctx.
 *
 *  It's now a pair, and is stored in request->pair_root.
 *  So it's wrong for anyone other than this function to play games with it.
 *
 * @param[in] request   to replace the state of.
 * @param[in] new_state state to assign to the request.
 *                      May be NULL in which case a new_state state will
 *                      be alloced and assigned.
 *
 * @return the fr_pair_t containing the old state list.
 */
fr_pair_t *request_state_replace(request_t *request, fr_pair_t *new_state)
{
        fr_pair_t *old = request->session_state_ctx;
 
        fr_assert(request->session_state_ctx != NULL);
        fr_assert(request->session_state_ctx != new_state);
 
        fr_pair_remove(&request->pair_root->children, old);
 
        /*
         *      Save (or delete) the existing state, and re-initialize
         *      it with a brand new one.
         */
        if (!new_state) MEM(new_state = fr_pair_afrom_da(NULL, request_attr_state));
 
        request->session_state_ctx = new_state;
 
        fr_pair_append(&request->pair_root->children, new_state);
 
        return old;
}
 
/** Unlink a subrequest from its parent
 *
 * @note This should be used for requests in preparation for freeing them.
 *
 * @param[in] child             request to unlink.
 * @return
 *       - 0 on success.
 *       - -1 on failure.
 */
int request_detach(request_t *child)
{
        request_t       *request = child->parent;
 
        /*
         *      Already detached or not detachable
         */
        if (request_is_detached(child)) return 0;
 
        if (!request_is_detachable(child)) {
                fr_strerror_const("Request is not detachable");
                return -1;
        }
 
        /*
         *      Unlink the child from the parent.
         */
        request_data_get(request, child, 0);
 
        child->parent = NULL;
 
        /*
         *      Request is now detached
         */
        child->type = REQUEST_TYPE_DETACHED;
 
        /*
         *      ...and is no longer detachable.
         */
        child->flags.detachable = 0;
 
        return 0;
}
 
static int _request_global_free(UNUSED void *uctx)
{
        fr_dict_autofree(request_dict);
        return 0;
}
 
static int _request_global_init(UNUSED void *uctx)
{
        if (fr_dict_autoload(request_dict) < 0) {
                PERROR("%s", __FUNCTION__);
                return -1;
        }
        if (fr_dict_attr_autoload(request_dict_attr) < 0) {
                PERROR("%s", __FUNCTION__);
                fr_dict_autofree(request_dict);
                return -1;
        }
        return 0;
}
 
int request_global_init(void)
{
        int ret;
        fr_atexit_global_once_ret(&ret, _request_global_init, _request_global_free, NULL);
        return ret;
}
 
#ifdef WITH_VERIFY_PTR
/*
 *      Verify a packet.
 */
static void packet_verify(char const *file, int line,
                          request_t const *request, fr_packet_t const *packet, fr_pair_list_t *list, char const *type)
{
        TALLOC_CTX *parent;
 
        fr_fatal_assert_msg(packet, "CONSISTENCY CHECK FAILED %s[%i]: fr_packet_t %s pointer was NULL",
                            file, line, type);
 
        parent = talloc_parent(packet);
        if (parent != request) {
                fr_log_talloc_report(packet);
                if (parent) fr_log_talloc_report(parent);
 
 
                fr_fatal_assert_fail("CONSISTENCY CHECK FAILED %s[%i]: Expected fr_packet_t %s to be parented "
                                     "by %p (%s), but parented by %p (%s)",
                                     file, line, type, request, talloc_get_name(request),
                                     parent, parent ? talloc_get_name(parent) : "NULL");
        }
 
        /*
         *      Enforce nesting at the top level.  This catches minor programming bugs in the server core.
         *
         *      If we care more, we could do these checks recursively.  But the tmpl_tokenize code already
         *      enforces parent / child namespaces.  So the end user shouldn't be able to break the parenting.
         *
         *      This code really only checks for programming bugs where the C code creates a pair, and then
         *      adds it to the wrong list.  This was happening during the transition from flat to nested, as
         *      the code was in the middle of being fixed.  It should only happen now if the programmer
         *      forgets, and uses the wrong APIs.
         */
        fr_pair_list_foreach(list, vp) {
                if (vp->da->flags.is_raw) continue;
 
                if (vp->da->flags.internal) continue;
 
                if (vp->da->depth > 1) {
                        fr_fatal_assert_fail("CONSISTENCY CHECK FAILED %s[%i]: Expected fr_pair_t %s to be parented "
                                     "by (%s), but it is instead at the top-level %s list",
                                             file, line, vp->da->name, vp->da->parent->name, type);
                }
        }
 
        PACKET_VERIFY(packet);
}
 
/*
 *      Catch horrible talloc errors.
 */
void request_verify(char const *file, int line, request_t const *request)
{
        request_data_t *rd = NULL;
 
        fr_fatal_assert_msg(request, "CONSISTENCY CHECK FAILED %s[%i]: request_t pointer was NULL", file, line);
 
        (void) talloc_get_type_abort_const(request, request_t);
 
        fr_assert(request->magic == REQUEST_MAGIC);
 
        (void)talloc_get_type_abort(request->request_ctx, fr_pair_t);
        fr_pair_list_verify(file, line, request->request_ctx, &request->request_pairs);
        (void)talloc_get_type_abort(request->reply_ctx, fr_pair_t);
        fr_pair_list_verify(file, line, request->reply_ctx, &request->reply_pairs);
        (void)talloc_get_type_abort(request->control_ctx, fr_pair_t);
        fr_pair_list_verify(file, line, request->control_ctx, &request->control_pairs);
        (void)talloc_get_type_abort(request->session_state_ctx, fr_pair_t);
 
#ifndef NDEBUG
        {
                TALLOC_CTX *parent = talloc_parent(request->session_state_ctx);
 
                fr_assert_msg((parent == NULL) || (parent == talloc_null_ctx()),
                              "session_state_ctx must not be parented by another chunk, but is parented by %s",
                              talloc_get_name(talloc_parent(request->session_state_ctx)));
        }
#endif
 
        fr_pair_list_verify(file, line, request->session_state_ctx, &request->session_state_pairs);
        fr_pair_list_verify(file, line, request->local_ctx, &request->local_pairs);
 
        fr_assert(request->proto_dict != NULL);
        fr_assert(request->local_dict != NULL);
 
        if (request->packet) {
                packet_verify(file, line, request, request->packet, &request->request_pairs, "request");
        }
        if (request->reply) {
                packet_verify(file, line, request, request->reply, &request->reply_pairs, "reply");
        }
 
        if (request->async) {
                (void) talloc_get_type_abort(request->async, fr_async_t);
                fr_assert(talloc_parent(request->async) == request);
        }
 
        while ((rd = fr_dlist_next(&request->data, rd))) {
                (void) talloc_get_type_abort(rd, request_data_t);
 
                if (request_data_persistable(rd)) {
                        fr_assert(request->session_state_ctx);
                        fr_assert(talloc_parent(rd) == request->session_state_ctx);
                } else {
                        fr_assert(talloc_parent(rd) == request);
                }
        }
}
#endif