rlm_client.c

Go to the documentation of this file.

/*
 *   This program is 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: b27095240c97e450b5518f00e475ddabaf26be86 $
 * @file rlm_client.c
 * @brief Reads client definitions from flat files as required.
 *
 * @copyright 2008 The FreeRADIUS server project
 * @copyright 2008 Alan DeKok (aland@deployingradius.com)
 * @copyright 2016 Arran Cudbard-Bell (a.cudbardb@freeradius.org)
 */
RCSID("$Id: b27095240c97e450b5518f00e475ddabaf26be86 $")
 
#include <freeradius-devel/server/base.h>
#include <freeradius-devel/server/module_rlm.h>
#include <freeradius-devel/unlang/xlat_func.h>
 
/** Client field
 *
 */
typedef struct {
        CONF_SECTION    *cs;            //!< Client's CONF_SECTION.
        CONF_PAIR       *cp;            //!< First instance of the field in the client's CONF_SECTION.
        char const      *field;         //!< Field name.
} client_get_vp_ctx_t;
 
static int _map_proc_client_get_vp(TALLOC_CTX *ctx, fr_pair_list_t *out, request_t *request,
                                   map_t const *map, void *uctx)
{
        client_get_vp_ctx_t     *client = uctx;
        fr_pair_list_t          head;
        fr_pair_t               *vp;
        fr_dict_attr_t const    *da;
        CONF_PAIR const         *cp;
 
        fr_assert(ctx != NULL);
 
        fr_pair_list_init(&head);
 
        /*
         *      FIXME: allow multiple entries.
         */
        if (tmpl_is_attr(map->lhs)) {
                da = tmpl_attr_tail_da(map->lhs);
        } else {
                char *attr;
 
                if (tmpl_aexpand(ctx, &attr, request, map->lhs, NULL, NULL) <= 0) {
                        RWDEBUG("Failed expanding string");
                error:
                        fr_pair_list_free(&head);
                        return -1;
                }
 
                da = fr_dict_attr_by_name(NULL, fr_dict_root(request->local_dict), attr);
                if (!da) {
                        RWDEBUG("No such attribute '%s'", attr);
                        talloc_free(attr);
                        goto error;
                }
 
                talloc_free(attr);
        }
 
        for (cp = client->cp;
             cp;
             cp = cf_pair_find_next(client->cs, cp, client->field)) {
                char const *value = cf_pair_value(cp);
 
                MEM(vp = fr_pair_afrom_da(ctx, da));
                if (fr_pair_value_from_str(vp, value, talloc_strlen(value), NULL, false) < 0) {
                        RWDEBUG("Failed parsing value \"%pV\" for attribute %s: %s", fr_box_strvalue(value),
                                tmpl_attr_tail_da(map->lhs)->name, fr_strerror());
                        talloc_free(vp);
                        goto error;
                }
 
                fr_pair_append(&head, vp);
 
                if (map->op != T_OP_ADD_EQ) break;      /* Create multiple attribute for multiple CONF_PAIRs */
        }
 
        fr_pair_list_append(out, &head);
 
        return 0;
}
 
/** Map multiple attributes from a client into the request
 *
 * @param[out] p_result         Result of applying the map:
 *                              - #RLM_MODULE_NOOP no rows were returned.
 *                              - #RLM_MODULE_UPDATED if one or more #fr_pair_t were added to the #request_t.
 *                              - #RLM_MODULE_FAIL if an error occurred.
 * @param[in] mpctx             NULL
 * @param[in] request           The current request.
 * @param[in] client_override   If NULL, use the current client, else use the client matching
 *                              the ip given.
 * @param[in] maps              Head of the map list.
 * @return UNLANG_ACTION_CALCULATE_RESULT
 */
static unlang_action_t map_proc_client(unlang_result_t *p_result, UNUSED map_ctx_t const *mpctx,
                                       request_t *request, fr_value_box_list_t *client_override, map_list_t const *maps)
{
        rlm_rcode_t             rcode = RLM_MODULE_OK;
        map_t const             *map = NULL;
        fr_client_t             *client;
        client_get_vp_ctx_t     uctx;
 
        if (!fr_value_box_list_empty(client_override)) {
                fr_ipaddr_t     ip;
                char const      *client_str;
                fr_value_box_t  *client_override_head = fr_value_box_list_head(client_override);
 
                /*
                 *      Concat don't asprint, as this becomes a noop
                 *      in the vast majority of cases.
                 */
                if (fr_value_box_list_concat_in_place(request,
                                                      client_override_head, client_override, FR_TYPE_STRING,
                                                      FR_VALUE_BOX_LIST_FREE, true,
                                                      SIZE_MAX) < 0) {
                        REDEBUG("Failed concatenating input data");
                        RETURN_UNLANG_FAIL;
                }
                client_str = client_override_head->vb_strvalue;
 
                if (fr_inet_pton(&ip, client_str, -1, AF_UNSPEC, false, true) < 0) {
                        REDEBUG("\"%s\" is not a valid IPv4 or IPv6 address", client_str);
                        rcode = RLM_MODULE_FAIL;
                        goto finish;
                }
 
                client = client_find(NULL, &ip, IPPROTO_IP);
                if (!client) {
                        RDEBUG("No client found with IP \"%s\"", client_str);
                        rcode = RLM_MODULE_NOTFOUND;
                        goto finish;
                }
 
                if (client->cs) {
                        char const *filename;
                        int line;
 
                        filename = cf_filename(client->cs);
                        line = cf_lineno(client->cs);
 
                        if (filename) {
                                RDEBUG2("Found client matching \"%s\".  Defined in \"%s\" line %i",
                                        client_str, filename, line);
                        } else {
                                RDEBUG2("Found client matching \"%s\"", client_str);
                        }
                }
        } else {
                client = client_from_request(request);
                if (!client) {
                        REDEBUG("No client associated with this request");
                        RETURN_UNLANG_FAIL;
                }
        }
        uctx.cs = client->cs;
 
        RINDENT();
        while ((map = map_list_next(maps, map))) {
                char    *field = NULL;
 
                if (tmpl_aexpand(request, &field, request, map->rhs, NULL, NULL) < 0) {
                        REDEBUG("Failed expanding RHS at %s", map->lhs->name);
                        rcode = RLM_MODULE_FAIL;
                        talloc_free(field);
                        break;
                }
 
                uctx.cp = cf_pair_find(client->cs, field);
                if (!uctx.cp) {
                        RDEBUG3("No matching client property \"%s\", skipping...", field);
                        goto next;                      /* No matching CONF_PAIR found */
                }
                uctx.field = field;
 
                /*
                 *      Pass the raw data to the callback, which will
                 *      create the VP and add it to the map.
                 */
                if (map_to_request(request, map, _map_proc_client_get_vp, &uctx) < 0) {
                        rcode = RLM_MODULE_FAIL;
                        talloc_free(field);
                        break;
                }
                rcode = RLM_MODULE_UPDATED;
 
        next:
                talloc_free(field);
        }
        REXDENT();
 
finish:
        RETURN_UNLANG_RCODE(rcode);
}
 
static xlat_arg_parser_t const xlat_client_args[] = {
        { .required = true, .single = true, .type = FR_TYPE_STRING },
        { .single = true, .type = FR_TYPE_STRING },
        XLAT_ARG_PARSER_TERMINATOR
};
 
/** xlat to get client config data
 *
 * Example:
@verbatim
%request.client(foo, [<ipaddr>])
@endverbatim
 *
 * @ingroup xlat_functions
 */
static xlat_action_t xlat_client(TALLOC_CTX *ctx, fr_dcursor_t *out,
                                 UNUSED xlat_ctx_t const *xctx,
                                 request_t *request, fr_value_box_list_t *in)
{
        char const      *value = NULL;
        fr_ipaddr_t     ip;
        CONF_PAIR       *cp;
        fr_client_t     *client = NULL;
        fr_value_box_t  *field = fr_value_box_list_head(in);
        fr_value_box_t  *client_ip = fr_value_box_list_next(in, field);
        fr_value_box_t  *vb;
 
        if (client_ip) {
                if (fr_inet_pton(&ip, client_ip->vb_strvalue, -1, AF_UNSPEC, false, true) < 0) {
                        RDEBUG("Invalid client IP address \"%s\"", client_ip->vb_strvalue);
                        return XLAT_ACTION_FAIL;
                }
 
                client = client_find(NULL, &ip, IPPROTO_IP);
                if (!client) {
                        RDEBUG("No client found with IP \"%s\"", client_ip->vb_strvalue);
                        return XLAT_ACTION_FAIL;
                }
        } else {
                client = client_from_request(request);
                if (!client) {
                        REDEBUG("No client associated with this request");
                        return XLAT_ACTION_FAIL;
                }
        }
 
        cp = cf_pair_find(client->cs, field->vb_strvalue);
        if (!cp || !(value = cf_pair_value(cp))) {
                if (strcmp(field->vb_strvalue, "shortname") == 0 && client->shortname) {
                        value = client->shortname;
                }
                else if (strcmp(field->vb_strvalue, "nas_type") == 0 && client->nas_type) {
                        value = client->nas_type;
                }
                if (!value) return XLAT_ACTION_DONE;
        }
 
        MEM(vb = fr_value_box_alloc_null(ctx));
 
        if (fr_value_box_strdup(ctx, vb, NULL, value, false) < 0) {
                talloc_free(vb);
                return XLAT_ACTION_FAIL;
        }
 
        fr_dcursor_append(out, vb);
        return XLAT_ACTION_DONE;
}
 
 
/*
 *      Find the client definition.
 */
static unlang_action_t CC_HINT(nonnull) mod_authorize(unlang_result_t *p_result, UNUSED module_ctx_t const *mctx, request_t *request)
{
        size_t          length;
        char const      *value;
        CONF_PAIR       *cp;
        char            buffer[2048];
        fr_client_t     *client;
 
        /*
         *      Ensure we're only being called from the main thread,
         *      with fake packets.
         */
        if ((request->packet->socket.inet.src_port != 0) || (!fr_pair_list_empty(&request->request_pairs)) ||
            (request->parent != NULL)) {
                REDEBUG("Improper configuration");
                RETURN_UNLANG_NOOP;
        }
 
        client = client_from_request(request);
        if (!client || !client->cs) {
                REDEBUG("Unknown client definition");
                RETURN_UNLANG_NOOP;
        }
 
        cp = cf_pair_find(client->cs, "directory");
        if (!cp) {
                REDEBUG("No directory configuration in the client");
                RETURN_UNLANG_NOOP;
        }
 
        value = cf_pair_value(cp);
        if (!value) {
                REDEBUG("No value given for the directory entry in the client");
                RETURN_UNLANG_NOOP;
        }
 
        length = strlen(value);
        if (length > (sizeof(buffer) - 256)) {
                REDEBUG("Directory name too long");
                RETURN_UNLANG_NOOP;
        }
 
        memcpy(buffer, value, length + 1);
        fr_inet_ntoh(&request->packet->socket.inet.src_ipaddr, buffer + length, sizeof(buffer) - length - 1);
 
        /*
         *      Read the buffer and generate the client.
         */
        if (!client->server) RETURN_UNLANG_FAIL;
 
        client = client_read(buffer, client->server_cs, true);
        if (!client) RETURN_UNLANG_FAIL;
 
        /*
         *      Replace the client.  This is more than a bit of a
         *      hack.
         */
        request->client = client;
 
        RETURN_UNLANG_OK;
}
 
static int mod_load(void)
{
        xlat_t  *xlat;
 
        if (unlikely((xlat = xlat_func_register(NULL, "client", xlat_client, FR_TYPE_STRING)) == NULL)) return -1;
        xlat_func_args_set(xlat, xlat_client_args);
 
        if (unlikely((xlat = xlat_func_register(NULL, "request.client", xlat_client, FR_TYPE_STRING)) == NULL)) return -1;
        xlat_func_args_set(xlat, xlat_client_args);
 
        map_proc_register(NULL, NULL, "client", map_proc_client, NULL, 0, FR_VALUE_BOX_SAFE_FOR_ANY);
 
        return 0;
}
 
static void mod_unload(void)
{
        xlat_func_unregister("client");
        map_proc_unregister("client");
}
 
/*
 *      The module name should be the only globally exported symbol.
 *      That is, everything else should be 'static'.
 *
 *      If the module needs to temporarily modify it's instantiation
 *      data, the type should be changed to MODULE_TYPE_THREAD_UNSAFE.
 *      The server will then take care of ensuring that the module
 *      is single-threaded.
 */
extern module_rlm_t rlm_client;
module_rlm_t rlm_client = {
        .common = {
                .magic          = MODULE_MAGIC_INIT,
                .name           = "dynamic_clients",
                .onload         = mod_load,
                .unload         = mod_unload
        },
        .method_group = {
                .bindings = (module_method_binding_t[]){
                        { .section = SECTION_NAME(CF_IDENT_ANY, CF_IDENT_ANY), .method = mod_authorize },
                        MODULE_BINDING_TERMINATOR
                }
        }
};