wps_upnp.c
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00001 /*
00002  * UPnP WPS Device
00003  * Copyright (c) 2000-2003 Intel Corporation
00004  * Copyright (c) 2006-2007 Sony Corporation
00005  * Copyright (c) 2008-2009 Atheros Communications
00006  * Copyright (c) 2009, Jouni Malinen <j@w1.fi>
00007  *
00008  * See below for more details on licensing and code history.
00009  */
00010 
00011 /*
00012  * This has been greatly stripped down from the original file
00013  * (upnp_wps_device.c) by Ted Merrill, Atheros Communications
00014  * in order to eliminate use of the bulky libupnp library etc.
00015  *
00016  * History:
00017  * upnp_wps_device.c is/was a shim layer between wps_opt_upnp.c and
00018  * the libupnp library.
00019  * The layering (by Sony) was well done; only a very minor modification
00020  * to API of upnp_wps_device.c was required.
00021  * libupnp was found to be undesirable because:
00022  * -- It consumed too much code and data space
00023  * -- It uses multiple threads, making debugging more difficult
00024  *      and possibly reducing reliability.
00025  * -- It uses static variables and only supports one instance.
00026  * The shim and libupnp are here replaced by special code written
00027  * specifically for the needs of hostapd.
00028  * Various shortcuts can and are taken to keep the code size small.
00029  * Generally, execution time is not as crucial.
00030  *
00031  * BUGS:
00032  * -- UPnP requires that we be able to resolve domain names.
00033  * While uncommon, if we have to do it then it will stall the entire
00034  * hostapd program, which is bad.
00035  * This is because we use the standard linux getaddrinfo() function
00036  * which is syncronous.
00037  * An asyncronous solution would be to use the free "ares" library.
00038  * -- Does not have a robust output buffering scheme.  Uses a single
00039  * fixed size output buffer per TCP/HTTP connection, with possible (although
00040  * unlikely) possibility of overflow and likely excessive use of RAM.
00041  * A better solution would be to write the HTTP output as a buffered stream,
00042  * using chunking: (handle header specially, then) generate data with
00043  * a printf-like function into a buffer, catching buffer full condition,
00044  * then send it out surrounded by http chunking.
00045  * -- There is some code that could be separated out into the common
00046  * library to be shared with wpa_supplicant.
00047  * -- Needs renaming with module prefix to avoid polluting the debugger
00048  * namespace and causing possible collisions with other static fncs
00049  * and structure declarations when using the debugger.
00050  * -- The http error code generation is pretty bogus, hopefully noone cares.
00051  *
00052  * Author: Ted Merrill, Atheros Communications, based upon earlier work
00053  * as explained above and below.
00054  *
00055  * Copyright:
00056  * Copyright 2008 Atheros Communications.
00057  *
00058  * The original header (of upnp_wps_device.c) reads:
00059  *
00060  *  Copyright (c) 2006-2007 Sony Corporation. All Rights Reserved.
00061  *
00062  *  File Name: upnp_wps_device.c
00063  *  Description: EAP-WPS UPnP device source
00064  *
00065  *   Redistribution and use in source and binary forms, with or without
00066  *   modification, are permitted provided that the following conditions
00067  *   are met:
00068  *
00069  *     * Redistributions of source code must retain the above copyright
00070  *       notice, this list of conditions and the following disclaimer.
00071  *     * Redistributions in binary form must reproduce the above copyright
00072  *       notice, this list of conditions and the following disclaimer in
00073  *       the documentation and/or other materials provided with the
00074  *       distribution.
00075  *     * Neither the name of Sony Corporation nor the names of its
00076  *       contributors may be used to endorse or promote products derived
00077  *       from this software without specific prior written permission.
00078  *
00079  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
00080  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
00081  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
00082  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
00083  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
00084  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
00085  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
00086  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
00087  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
00088  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
00089  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00090  *
00091  * Portions from Intel libupnp files, e.g. genlib/net/http/httpreadwrite.c
00092  * typical header:
00093  *
00094  * Copyright (c) 2000-2003 Intel Corporation
00095  * All rights reserved.
00096  *
00097  * Redistribution and use in source and binary forms, with or without
00098  * modification, are permitted provided that the following conditions are met:
00099  *
00100  * * Redistributions of source code must retain the above copyright notice,
00101  * this list of conditions and the following disclaimer.
00102  * * Redistributions in binary form must reproduce the above copyright notice,
00103  * this list of conditions and the following disclaimer in the documentation
00104  * and/or other materials provided with the distribution.
00105  * * Neither name of Intel Corporation nor the names of its contributors
00106  * may be used to endorse or promote products derived from this software
00107  * without specific prior written permission.
00108  *
00109  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
00110  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
00111  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
00112  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL OR
00113  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
00114  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
00115  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
00116  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
00117  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
00118  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
00119  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00120 */
00121 
00122 /*
00123  * Overview of WPS over UPnP:
00124  *
00125  * UPnP is a protocol that allows devices to discover each other and control
00126  * each other. In UPnP terminology, a device is either a "device" (a server
00127  * that provides information about itself and allows itself to be controlled)
00128  * or a "control point" (a client that controls "devices") or possibly both.
00129  * This file implements a UPnP "device".
00130  *
00131  * For us, we use mostly basic UPnP discovery, but the control part of interest
00132  * is WPS carried via UPnP messages. There is quite a bit of basic UPnP
00133  * discovery to do before we can get to WPS, however.
00134  *
00135  * UPnP discovery begins with "devices" send out multicast UDP packets to a
00136  * certain fixed multicast IP address and port, and "control points" sending
00137  * out other such UDP packets.
00138  *
00139  * The packets sent by devices are NOTIFY packets (not to be confused with TCP
00140  * NOTIFY packets that are used later) and those sent by control points are
00141  * M-SEARCH packets. These packets contain a simple HTTP style header. The
00142  * packets are sent redundantly to get around packet loss. Devices respond to
00143  * M-SEARCH packets with HTTP-like UDP packets containing HTTP/1.1 200 OK
00144  * messages, which give similar information as the UDP NOTIFY packets.
00145  *
00146  * The above UDP packets advertise the (arbitrary) TCP ports that the
00147  * respective parties will listen to. The control point can then do a HTTP
00148  * SUBSCRIBE (something like an HTTP PUT) after which the device can do a
00149  * separate HTTP NOTIFY (also like an HTTP PUT) to do event messaging.
00150  *
00151  * The control point will also do HTTP GET of the "device file" listed in the
00152  * original UDP information from the device (see UPNP_WPS_DEVICE_XML_FILE
00153  * data), and based on this will do additional GETs... HTTP POSTs are done to
00154  * cause an action.
00155  *
00156  * Beyond some basic information in HTTP headers, additional information is in
00157  * the HTTP bodies, in a format set by the SOAP and XML standards, a markup
00158  * language related to HTML used for web pages. This language is intended to
00159  * provide the ultimate in self-documentation by providing a universal
00160  * namespace based on pseudo-URLs called URIs. Note that although a URI looks
00161  * like a URL (a web address), they are never accessed as such but are used
00162  * only as identifiers.
00163  *
00164  * The POST of a GetDeviceInfo gets information similar to what might be
00165  * obtained from a probe request or response on Wi-Fi. WPS messages M1-M8
00166  * are passed via a POST of a PutMessage; the M1-M8 WPS messages are converted
00167  * to a bin64 ascii representation for encapsulation. When proxying messages,
00168  * WLANEvent and PutWLANResponse are used.
00169  *
00170  * This of course glosses over a lot of details.
00171  */
00172 
00173 #include "includes.h"
00174 
00175 #include <assert.h>
00176 #include <net/if.h>
00177 #include <netdb.h>
00178 #include <sys/ioctl.h>
00179 
00180 #include "common.h"
00181 #include "uuid.h"
00182 #include "base64.h"
00183 #include "wps.h"
00184 #include "wps_i.h"
00185 #include "wps_upnp.h"
00186 #include "wps_upnp_i.h"
00187 
00188 
00189 /*
00190  * UPnP allows a client ("control point") to send a server like us ("device")
00191  * a domain name for registration, and we are supposed to resolve it. This is
00192  * bad because, using the standard Linux library, we will stall the entire
00193  * hostapd waiting for resolution.
00194  *
00195  * The "correct" solution would be to use an event driven library for domain
00196  * name resolution such as "ares". However, this would increase code size
00197  * further. Since it is unlikely that we'll actually see such domain names, we
00198  * can just refuse to accept them.
00199  */
00200 #define NO_DOMAIN_NAME_RESOLUTION 1  /* 1 to allow only dotted ip addresses */
00201 
00202 
00203 /*
00204  * UPnP does not scale well. If we were in a room with thousands of control
00205  * points then potentially we could be expected to handle subscriptions for
00206  * each of them, which would exhaust our memory. So we must set a limit. In
00207  * practice we are unlikely to see more than one or two.
00208  */
00209 #define MAX_SUBSCRIPTIONS 4    /* how many subscribing clients we handle */
00210 #define MAX_ADDR_PER_SUBSCRIPTION 8
00211 
00212 
00213 /* Write the current date/time per RFC */
00214 void format_date(struct wpabuf *buf)
00215 {
00216         const char *weekday_str = "Sun\0Mon\0Tue\0Wed\0Thu\0Fri\0Sat";
00217         const char *month_str = "Jan\0Feb\0Mar\0Apr\0May\0Jun\0"
00218                 "Jul\0Aug\0Sep\0Oct\0Nov\0Dec";
00219         struct tm *date;
00220         time_t t;
00221 
00222         t = time(NULL);
00223         date = gmtime(&t);
00224         wpabuf_printf(buf, "%s, %02d %s %d %02d:%02d:%02d GMT",
00225                       &weekday_str[date->tm_wday * 4], date->tm_mday,
00226                       &month_str[date->tm_mon * 4], date->tm_year + 1900,
00227                       date->tm_hour, date->tm_min, date->tm_sec);
00228 }
00229 
00230 
00231 /***************************************************************************
00232  * UUIDs (unique identifiers)
00233  *
00234  * These are supposed to be unique in all the world.
00235  * Sometimes permanent ones are used, sometimes temporary ones
00236  * based on random numbers... there are different rules for valid content
00237  * of different types.
00238  * Each uuid is 16 bytes long.
00239  **************************************************************************/
00240 
00241 /* uuid_make -- construct a random UUID
00242  * The UPnP documents don't seem to offer any guidelines as to which method to
00243  * use for constructing UUIDs for subscriptions. Presumably any method from
00244  * rfc4122 is good enough; I've chosen random number method.
00245  */
00246 static void uuid_make(u8 uuid[UUID_LEN])
00247 {
00248         os_get_random(uuid, UUID_LEN);
00249 
00250         /* Replace certain bits as specified in rfc4122 or X.667 */
00251         uuid[6] &= 0x0f; uuid[6] |= (4 << 4);   /* version 4 == random gen */
00252         uuid[8] &= 0x3f; uuid[8] |= 0x80;
00253 }
00254 
00255 
00256 /*
00257  * Subscriber address handling.
00258  * Since a subscriber may have an arbitrary number of addresses, we have to
00259  * add a bunch of code to handle them.
00260  *
00261  * Addresses are passed in text, and MAY be domain names instead of the (usual
00262  * and expected) dotted IP addresses. Resolving domain names consumes a lot of
00263  * resources. Worse, we are currently using the standard Linux getaddrinfo()
00264  * which will block the entire program until complete or timeout! The proper
00265  * solution would be to use the "ares" library or similar with more state
00266  * machine steps etc. or just disable domain name resolution by setting
00267  * NO_DOMAIN_NAME_RESOLUTION to 1 at top of this file.
00268  */
00269 
00270 /* subscr_addr_delete -- delete single unlinked subscriber address
00271  * (be sure to unlink first if need be)
00272  */
00273 static void subscr_addr_delete(struct subscr_addr *a)
00274 {
00275         /*
00276          * Note: do NOT free domain_and_port or path because they point to
00277          * memory within the allocation of "a".
00278          */
00279         os_free(a);
00280 }
00281 
00282 
00283 /* subscr_addr_free_all -- unlink and delete list of subscriber addresses. */
00284 static void subscr_addr_free_all(struct subscription *s)
00285 {
00286         struct subscr_addr *a, *tmp;
00287         dl_list_for_each_safe(a, tmp, &s->addr_list, struct subscr_addr, list)
00288         {
00289                 dl_list_del(&a->list);
00290                 subscr_addr_delete(a);
00291         }
00292 }
00293 
00294 
00295 /* subscr_addr_add_url -- add address(es) for one url to subscription */
00296 static void subscr_addr_add_url(struct subscription *s, const char *url)
00297 {
00298         int alloc_len;
00299         char *scratch_mem = NULL;
00300         char *mem;
00301         char *domain_and_port;
00302         char *delim;
00303         char *path;
00304         char *domain;
00305         int port = 80;  /* port to send to (default is port 80) */
00306         struct addrinfo hints;
00307         struct addrinfo *result = NULL;
00308         struct addrinfo *rp;
00309         int rerr;
00310         struct subscr_addr *a = NULL;
00311 
00312         /* url MUST begin with http: */
00313         if (os_strncasecmp(url, "http://", 7))
00314                 goto fail;
00315         url += 7;
00316 
00317         /* allocate memory for the extra stuff we need */
00318         alloc_len = (2 * (os_strlen(url) + 1));
00319         scratch_mem = os_zalloc(alloc_len);
00320         if (scratch_mem == NULL)
00321                 goto fail;
00322         mem = scratch_mem;
00323         strcpy(mem, url);
00324         domain_and_port = mem;
00325         mem += 1 + os_strlen(mem);
00326         delim = os_strchr(domain_and_port, '/');
00327         if (delim) {
00328                 *delim++ = 0;   /* null terminate domain and port */
00329                 path = delim;
00330         } else {
00331                 path = domain_and_port + os_strlen(domain_and_port);
00332         }
00333         domain = mem;
00334         strcpy(domain, domain_and_port);
00335         delim = strchr(domain, ':');
00336         if (delim) {
00337                 *delim++ = 0;   /* null terminate domain */
00338                 if (isdigit(*delim))
00339                         port = atol(delim);
00340         }
00341 
00342         /*
00343          * getaddrinfo does the right thing with dotted decimal notations, or
00344          * will resolve domain names. Resolving domain names will unfortunately
00345          * hang the entire program until it is resolved or it times out
00346          * internal to getaddrinfo; fortunately we think that the use of actual
00347          * domain names (vs. dotted decimal notations) should be uncommon.
00348          */
00349         os_memset(&hints, 0, sizeof(struct addrinfo));
00350         hints.ai_family = AF_INET;      /* IPv4 */
00351         hints.ai_socktype = SOCK_STREAM;
00352 #if NO_DOMAIN_NAME_RESOLUTION
00353         /* Suppress domain name resolutions that would halt
00354          * the program for periods of time
00355          */
00356         hints.ai_flags = AI_NUMERICHOST;
00357 #else
00358         /* Allow domain name resolution. */
00359         hints.ai_flags = 0;
00360 #endif
00361         hints.ai_protocol = 0;          /* Any protocol? */
00362         rerr = getaddrinfo(domain, NULL /* fill in port ourselves */,
00363                            &hints, &result);
00364         if (rerr) {
00365                 wpa_printf(MSG_INFO, "WPS UPnP: Resolve error %d (%s) on: %s",
00366                            rerr, gai_strerror(rerr), domain);
00367                 goto fail;
00368         }
00369         for (rp = result; rp; rp = rp->ai_next) {
00370                 /* Limit no. of address to avoid denial of service attack */
00371                 if (dl_list_len(&s->addr_list) >= MAX_ADDR_PER_SUBSCRIPTION) {
00372                         wpa_printf(MSG_INFO, "WPS UPnP: subscr_addr_add_url: "
00373                                    "Ignoring excessive addresses");
00374                         break;
00375                 }
00376 
00377                 a = os_zalloc(sizeof(*a) + alloc_len);
00378                 if (a == NULL)
00379                         continue;
00380                 mem = (void *) (a + 1);
00381                 a->domain_and_port = mem;
00382                 strcpy(mem, domain_and_port);
00383                 mem += 1 + strlen(mem);
00384                 a->path = mem;
00385                 if (path[0] != '/')
00386                         *mem++ = '/';
00387                 strcpy(mem, path);
00388                 mem += 1 + strlen(mem);
00389                 os_memcpy(&a->saddr, rp->ai_addr, sizeof(a->saddr));
00390                 a->saddr.sin_port = htons(port);
00391 
00392                 dl_list_add(&s->addr_list, &a->list);
00393                 a = NULL;       /* don't free it below */
00394         }
00395 
00396 fail:
00397         if (result)
00398                 freeaddrinfo(result);
00399         os_free(scratch_mem);
00400         os_free(a);
00401 }
00402 
00403 
00404 /* subscr_addr_list_create -- create list from urls in string.
00405  *      Each url is enclosed by angle brackets.
00406  */
00407 static void subscr_addr_list_create(struct subscription *s,
00408                                     const char *url_list)
00409 {
00410         char *end;
00411         for (;;) {
00412                 while (*url_list == ' ' || *url_list == '\t')
00413                         url_list++;
00414                 if (*url_list != '<')
00415                         break;
00416                 url_list++;
00417                 end = os_strchr(url_list, '>');
00418                 if (end == NULL)
00419                         break;
00420                 *end++ = 0;
00421                 subscr_addr_add_url(s, url_list);
00422                 url_list = end;
00423         }
00424 }
00425 
00426 
00427 int send_wpabuf(int fd, struct wpabuf *buf)
00428 {
00429         wpa_printf(MSG_DEBUG, "WPS UPnP: Send %lu byte message",
00430                    (unsigned long) wpabuf_len(buf));
00431         errno = 0;
00432         if (write(fd, wpabuf_head(buf), wpabuf_len(buf)) !=
00433             (int) wpabuf_len(buf)) {
00434                 wpa_printf(MSG_ERROR, "WPS UPnP: Failed to send buffer: "
00435                            "errno=%d (%s)",
00436                            errno, strerror(errno));
00437                 return -1;
00438         }
00439 
00440         return 0;
00441 }
00442 
00443 
00444 static void wpabuf_put_property(struct wpabuf *buf, const char *name,
00445                                 const char *value)
00446 {
00447         wpabuf_put_str(buf, "<e:property>");
00448         wpabuf_printf(buf, "<%s>", name);
00449         if (value)
00450                 wpabuf_put_str(buf, value);
00451         wpabuf_printf(buf, "</%s>", name);
00452         wpabuf_put_str(buf, "</e:property>\n");
00453 }
00454 
00455 
00464 static void upnp_wps_device_send_event(struct upnp_wps_device_sm *sm)
00465 {
00466         /* Enqueue event message for all subscribers */
00467         struct wpabuf *buf; /* holds event message */
00468         int buf_size = 0;
00469         struct subscription *s, *tmp;
00470         /* Actually, utf-8 is the default, but it doesn't hurt to specify it */
00471         const char *format_head =
00472                 "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"
00473                 "<e:propertyset xmlns:e=\"urn:schemas-upnp-org:event-1-0\">\n";
00474         const char *format_tail = "</e:propertyset>\n";
00475 
00476         if (dl_list_empty(&sm->subscriptions)) {
00477                 /* optimize */
00478                 return;
00479         }
00480 
00481         /* Determine buffer size needed first */
00482         buf_size += os_strlen(format_head);
00483         buf_size += 50 + 2 * os_strlen("WLANEvent");
00484         if (sm->wlanevent)
00485                 buf_size += os_strlen(sm->wlanevent);
00486         buf_size += os_strlen(format_tail);
00487 
00488         buf = wpabuf_alloc(buf_size);
00489         if (buf == NULL)
00490                 return;
00491         wpabuf_put_str(buf, format_head);
00492         wpabuf_put_property(buf, "WLANEvent", sm->wlanevent);
00493         wpabuf_put_str(buf, format_tail);
00494 
00495         wpa_printf(MSG_MSGDUMP, "WPS UPnP: WLANEvent message:\n%s",
00496                    (char *) wpabuf_head(buf));
00497 
00498         dl_list_for_each_safe(s, tmp, &sm->subscriptions, struct subscription,
00499                               list) {
00500                 if (event_add(s, buf)) {
00501                         wpa_printf(MSG_INFO, "WPS UPnP: Dropping "
00502                                    "subscriber due to event backlog");
00503                         dl_list_del(&s->list);
00504                         subscription_destroy(s);
00505                 }
00506         }
00507 
00508         wpabuf_free(buf);
00509 }
00510 
00511 
00512 /*
00513  * Event subscription (subscriber machines register with us to receive event
00514  * messages).
00515  * This is the result of an incoming HTTP over TCP SUBSCRIBE request.
00516  */
00517 
00518 /* subscription_destroy -- destroy an unlinked subscription
00519  * Be sure to unlink first if necessary.
00520  */
00521 void subscription_destroy(struct subscription *s)
00522 {
00523         wpa_printf(MSG_DEBUG, "WPS UPnP: Destroy subscription %p", s);
00524         subscr_addr_free_all(s);
00525         event_delete_all(s);
00526         upnp_er_remove_notification(s);
00527         os_free(s);
00528 }
00529 
00530 
00531 /* subscription_list_age -- remove expired subscriptions */
00532 static void subscription_list_age(struct upnp_wps_device_sm *sm, time_t now)
00533 {
00534         struct subscription *s, *tmp;
00535         dl_list_for_each_safe(s, tmp, &sm->subscriptions,
00536                               struct subscription, list) {
00537                 if (s->timeout_time > now)
00538                         break;
00539                 wpa_printf(MSG_DEBUG, "WPS UPnP: Removing aged subscription");
00540                 dl_list_del(&s->list);
00541                 subscription_destroy(s);
00542         }
00543 }
00544 
00545 
00546 /* subscription_find -- return existing subscription matching uuid, if any
00547  * returns NULL if not found
00548  */
00549 struct subscription * subscription_find(struct upnp_wps_device_sm *sm,
00550                                         const u8 uuid[UUID_LEN])
00551 {
00552         struct subscription *s;
00553         dl_list_for_each(s, &sm->subscriptions, struct subscription, list) {
00554                 if (os_memcmp(s->uuid, uuid, UUID_LEN) == 0)
00555                         return s; /* Found match */
00556         }
00557         return NULL;
00558 }
00559 
00560 
00561 static struct wpabuf * build_fake_wsc_ack(void)
00562 {
00563         struct wpabuf *msg = wpabuf_alloc(100);
00564         if (msg == NULL)
00565                 return NULL;
00566         wpabuf_put_u8(msg, UPNP_WPS_WLANEVENT_TYPE_EAP);
00567         wpabuf_put_str(msg, "00:00:00:00:00:00");
00568         if (wps_build_version(msg) ||
00569             wps_build_msg_type(msg, WPS_WSC_ACK)) {
00570                 wpabuf_free(msg);
00571                 return NULL;
00572         }
00573         /* Enrollee Nonce */
00574         wpabuf_put_be16(msg, ATTR_ENROLLEE_NONCE);
00575         wpabuf_put_be16(msg, WPS_NONCE_LEN);
00576         wpabuf_put(msg, WPS_NONCE_LEN);
00577         /* Registrar Nonce */
00578         wpabuf_put_be16(msg, ATTR_REGISTRAR_NONCE);
00579         wpabuf_put_be16(msg, WPS_NONCE_LEN);
00580         wpabuf_put(msg, WPS_NONCE_LEN);
00581         return msg;
00582 }
00583 
00584 
00585 /* subscription_first_event -- send format/queue event that is automatically
00586  * sent on a new subscription.
00587  */
00588 static int subscription_first_event(struct subscription *s)
00589 {
00590         /*
00591          * Actually, utf-8 is the default, but it doesn't hurt to specify it.
00592          *
00593          * APStatus is apparently a bit set,
00594          * 0x1 = configuration change (but is always set?)
00595          * 0x10 = ap is locked
00596          *
00597          * Per UPnP spec, we send out the last value of each variable, even
00598          * for WLANEvent, whatever it was.
00599          */
00600         char *wlan_event;
00601         struct wpabuf *buf;
00602         int ap_status = 1;      /* TODO: add 0x10 if access point is locked */
00603         const char *head =
00604                 "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"
00605                 "<e:propertyset xmlns:e=\"urn:schemas-upnp-org:event-1-0\">\n";
00606         const char *tail = "</e:propertyset>\n";
00607         char txt[10];
00608 
00609         if (s->sm->wlanevent == NULL) {
00610                 /*
00611                  * There has been no events before the subscription. However,
00612                  * UPnP device architecture specification requires all the
00613                  * evented variables to be included, so generate a dummy event
00614                  * for this particular case using a WSC_ACK and all-zeros
00615                  * nonces. The ER (UPnP control point) will ignore this, but at
00616                  * least it will learn that WLANEvent variable will be used in
00617                  * event notifications in the future.
00618                  */
00619                 struct wpabuf *msg;
00620                 wpa_printf(MSG_DEBUG, "WPS UPnP: Use a fake WSC_ACK as the "
00621                            "initial WLANEvent");
00622                 msg = build_fake_wsc_ack();
00623                 if (msg) {
00624                         s->sm->wlanevent = (char *)
00625                                 base64_encode(wpabuf_head(msg),
00626                                               wpabuf_len(msg), NULL);
00627                         wpabuf_free(msg);
00628                 }
00629         }
00630 
00631         wlan_event = s->sm->wlanevent;
00632         if (wlan_event == NULL || *wlan_event == '\0') {
00633                 wpa_printf(MSG_DEBUG, "WPS UPnP: WLANEvent not known for "
00634                            "initial event message");
00635                 wlan_event = "";
00636         }
00637         buf = wpabuf_alloc(500 + os_strlen(wlan_event));
00638         if (buf == NULL)
00639                 return 1;
00640 
00641         wpabuf_put_str(buf, head);
00642         wpabuf_put_property(buf, "STAStatus", "1");
00643         os_snprintf(txt, sizeof(txt), "%d", ap_status);
00644         wpabuf_put_property(buf, "APStatus", txt);
00645         if (*wlan_event)
00646                 wpabuf_put_property(buf, "WLANEvent", wlan_event);
00647         wpabuf_put_str(buf, tail);
00648 
00649         if (event_add(s, buf)) {
00650                 wpabuf_free(buf);
00651                 return 1;
00652         }
00653         wpabuf_free(buf);
00654 
00655         return 0;
00656 }
00657 
00658 
00665 struct subscription * subscription_start(struct upnp_wps_device_sm *sm,
00666                                          const char *callback_urls)
00667 {
00668         struct subscription *s;
00669         time_t now = time(NULL);
00670         time_t expire = now + UPNP_SUBSCRIBE_SEC;
00671 
00672         /* Get rid of expired subscriptions so we have room */
00673         subscription_list_age(sm, now);
00674 
00675         /* If too many subscriptions, remove oldest */
00676         if (dl_list_len(&sm->subscriptions) >= MAX_SUBSCRIPTIONS) {
00677                 s = dl_list_first(&sm->subscriptions, struct subscription,
00678                                   list);
00679                 wpa_printf(MSG_INFO, "WPS UPnP: Too many subscriptions, "
00680                            "trashing oldest");
00681                 dl_list_del(&s->list);
00682                 subscription_destroy(s);
00683         }
00684 
00685         s = os_zalloc(sizeof(*s));
00686         if (s == NULL)
00687                 return NULL;
00688         dl_list_init(&s->addr_list);
00689         dl_list_init(&s->event_queue);
00690 
00691         s->sm = sm;
00692         s->timeout_time = expire;
00693         uuid_make(s->uuid);
00694         subscr_addr_list_create(s, callback_urls);
00695         /* Add to end of list, since it has the highest expiration time */
00696         dl_list_add_tail(&sm->subscriptions, &s->list);
00697         /* Queue up immediate event message (our last event)
00698          * as required by UPnP spec.
00699          */
00700         if (subscription_first_event(s)) {
00701                 wpa_printf(MSG_INFO, "WPS UPnP: Dropping subscriber due to "
00702                            "event backlog");
00703                 dl_list_del(&s->list);
00704                 subscription_destroy(s);
00705                 return NULL;
00706         }
00707         wpa_printf(MSG_DEBUG, "WPS UPnP: Subscription %p started with %s",
00708                    s, callback_urls);
00709         /* Schedule sending this */
00710         event_send_all_later(sm);
00711         return s;
00712 }
00713 
00714 
00715 /* subscription_renew -- find subscription and reset timeout */
00716 struct subscription * subscription_renew(struct upnp_wps_device_sm *sm,
00717                                          const u8 uuid[UUID_LEN])
00718 {
00719         time_t now = time(NULL);
00720         time_t expire = now + UPNP_SUBSCRIBE_SEC;
00721         struct subscription *s = subscription_find(sm, uuid);
00722         if (s == NULL)
00723                 return NULL;
00724         wpa_printf(MSG_DEBUG, "WPS UPnP: Subscription renewed");
00725         dl_list_del(&s->list);
00726         s->timeout_time = expire;
00727         /* add back to end of list, since it now has highest expiry */
00728         dl_list_add_tail(&sm->subscriptions, &s->list);
00729         return s;
00730 }
00731 
00732 
00745 int upnp_wps_device_send_wlan_event(struct upnp_wps_device_sm *sm,
00746                                     const u8 from_mac_addr[ETH_ALEN],
00747                                     enum upnp_wps_wlanevent_type ev_type,
00748                                     const struct wpabuf *msg)
00749 {
00750         int ret = -1;
00751         char type[2];
00752         const u8 *mac = from_mac_addr;
00753         char mac_text[18];
00754         u8 *raw = NULL;
00755         size_t raw_len;
00756         char *val;
00757         size_t val_len;
00758         int pos = 0;
00759 
00760         if (!sm)
00761                 goto fail;
00762 
00763         os_snprintf(type, sizeof(type), "%1u", ev_type);
00764 
00765         raw_len = 1 + 17 + (msg ? wpabuf_len(msg) : 0);
00766         raw = os_zalloc(raw_len);
00767         if (!raw)
00768                 goto fail;
00769 
00770         *(raw + pos) = (u8) ev_type;
00771         pos += 1;
00772         os_snprintf(mac_text, sizeof(mac_text), MACSTR, MAC2STR(mac));
00773         wpa_printf(MSG_DEBUG, "WPS UPnP: Proxying WLANEvent from %s",
00774                    mac_text);
00775         os_memcpy(raw + pos, mac_text, 17);
00776         pos += 17;
00777         if (msg) {
00778                 os_memcpy(raw + pos, wpabuf_head(msg), wpabuf_len(msg));
00779                 pos += wpabuf_len(msg);
00780         }
00781         raw_len = pos;
00782 
00783         val = (char *) base64_encode(raw, raw_len, &val_len);
00784         if (val == NULL)
00785                 goto fail;
00786 
00787         os_free(sm->wlanevent);
00788         sm->wlanevent = val;
00789         upnp_wps_device_send_event(sm);
00790 
00791         ret = 0;
00792 
00793 fail:
00794         os_free(raw);
00795 
00796         return ret;
00797 }
00798 
00799 
00800 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
00801 #include <sys/sysctl.h>
00802 #include <net/route.h>
00803 #include <net/if_dl.h>
00804 
00805 static int eth_get(const char *device, u8 ea[ETH_ALEN])
00806 {
00807         struct if_msghdr *ifm;
00808         struct sockaddr_dl *sdl;
00809         u_char *p, *buf;
00810         size_t len;
00811         int mib[] = { CTL_NET, AF_ROUTE, 0, AF_LINK, NET_RT_IFLIST, 0 };
00812 
00813         if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0)
00814                 return -1;
00815         if ((buf = os_malloc(len)) == NULL)
00816                 return -1;
00817         if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
00818                 os_free(buf);
00819                 return -1;
00820         }
00821         for (p = buf; p < buf + len; p += ifm->ifm_msglen) {
00822                 ifm = (struct if_msghdr *)p;
00823                 sdl = (struct sockaddr_dl *)(ifm + 1);
00824                 if (ifm->ifm_type != RTM_IFINFO ||
00825                     (ifm->ifm_addrs & RTA_IFP) == 0)
00826                         continue;
00827                 if (sdl->sdl_family != AF_LINK || sdl->sdl_nlen == 0 ||
00828                     os_memcmp(sdl->sdl_data, device, sdl->sdl_nlen) != 0)
00829                         continue;
00830                 os_memcpy(ea, LLADDR(sdl), sdl->sdl_alen);
00831                 break;
00832         }
00833         os_free(buf);
00834 
00835         if (p >= buf + len) {
00836                 errno = ESRCH;
00837                 return -1;
00838         }
00839         return 0;
00840 }
00841 #endif /* __FreeBSD__ */
00842 
00843 
00852 int get_netif_info(const char *net_if, unsigned *ip_addr, char **ip_addr_text,
00853                    u8 mac[ETH_ALEN])
00854 {
00855         struct ifreq req;
00856         int sock = -1;
00857         struct sockaddr_in *addr;
00858         struct in_addr in_addr;
00859 
00860         *ip_addr_text = os_zalloc(16);
00861         if (*ip_addr_text == NULL)
00862                 goto fail;
00863 
00864         sock = socket(AF_INET, SOCK_DGRAM, 0);
00865         if (sock < 0)
00866                 goto fail;
00867 
00868         os_strlcpy(req.ifr_name, net_if, sizeof(req.ifr_name));
00869         if (ioctl(sock, SIOCGIFADDR, &req) < 0) {
00870                 wpa_printf(MSG_ERROR, "WPS UPnP: SIOCGIFADDR failed: %d (%s)",
00871                            errno, strerror(errno));
00872                 goto fail;
00873         }
00874         addr = (void *) &req.ifr_addr;
00875         *ip_addr = addr->sin_addr.s_addr;
00876         in_addr.s_addr = *ip_addr;
00877         os_snprintf(*ip_addr_text, 16, "%s", inet_ntoa(in_addr));
00878 
00879 #ifdef __linux__
00880         os_strlcpy(req.ifr_name, net_if, sizeof(req.ifr_name));
00881         if (ioctl(sock, SIOCGIFHWADDR, &req) < 0) {
00882                 wpa_printf(MSG_ERROR, "WPS UPnP: SIOCGIFHWADDR failed: "
00883                            "%d (%s)", errno, strerror(errno));
00884                 goto fail;
00885         }
00886         os_memcpy(mac, req.ifr_addr.sa_data, 6);
00887 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
00888         if (eth_get(net_if, mac) < 0) {
00889                 wpa_printf(MSG_ERROR, "WPS UPnP: Failed to get MAC address");
00890                 goto fail;
00891         }
00892 #else
00893 #error MAC address fetch not implemented
00894 #endif
00895 
00896         close(sock);
00897         return 0;
00898 
00899 fail:
00900         if (sock >= 0)
00901                 close(sock);
00902         os_free(*ip_addr_text);
00903         *ip_addr_text = NULL;
00904         return -1;
00905 }
00906 
00907 
00908 static void upnp_wps_free_msearchreply(struct dl_list *head)
00909 {
00910         struct advertisement_state_machine *a, *tmp;
00911         dl_list_for_each_safe(a, tmp, head, struct advertisement_state_machine,
00912                               list)
00913                 msearchreply_state_machine_stop(a);
00914 }
00915 
00916 
00917 static void upnp_wps_free_subscriptions(struct dl_list *head)
00918 {
00919         struct subscription *s, *tmp;
00920         dl_list_for_each_safe(s, tmp, head, struct subscription, list) {
00921                 dl_list_del(&s->list);
00922                 subscription_destroy(s);
00923         }
00924 }
00925 
00926 
00931 void upnp_wps_device_stop(struct upnp_wps_device_sm *sm)
00932 {
00933         if (!sm || !sm->started)
00934                 return;
00935 
00936         wpa_printf(MSG_DEBUG, "WPS UPnP: Stop device");
00937         web_listener_stop(sm);
00938         upnp_wps_free_msearchreply(&sm->msearch_replies);
00939         upnp_wps_free_subscriptions(&sm->subscriptions);
00940 
00941         advertisement_state_machine_stop(sm, 1);
00942 
00943         event_send_stop_all(sm);
00944         os_free(sm->wlanevent);
00945         sm->wlanevent = NULL;
00946         os_free(sm->ip_addr_text);
00947         sm->ip_addr_text = NULL;
00948         if (sm->multicast_sd >= 0)
00949                 close(sm->multicast_sd);
00950         sm->multicast_sd = -1;
00951         ssdp_listener_stop(sm);
00952 
00953         sm->started = 0;
00954 }
00955 
00956 
00963 int upnp_wps_device_start(struct upnp_wps_device_sm *sm, char *net_if)
00964 {
00965         if (!sm || !net_if)
00966                 return -1;
00967 
00968         if (sm->started)
00969                 upnp_wps_device_stop(sm);
00970 
00971         sm->multicast_sd = -1;
00972         sm->ssdp_sd = -1;
00973         sm->started = 1;
00974         sm->advertise_count = 0;
00975 
00976         /* Fix up linux multicast handling */
00977         if (add_ssdp_network(net_if))
00978                 goto fail;
00979 
00980         /* Determine which IP and mac address we're using */
00981         if (get_netif_info(net_if, &sm->ip_addr, &sm->ip_addr_text,
00982                            sm->mac_addr)) {
00983                 wpa_printf(MSG_INFO, "WPS UPnP: Could not get IP/MAC address "
00984                            "for %s. Does it have IP address?", net_if);
00985                 goto fail;
00986         }
00987 
00988         /* Listen for incoming TCP connections so that others
00989          * can fetch our "xml files" from us.
00990          */
00991         if (web_listener_start(sm))
00992                 goto fail;
00993 
00994         /* Set up for receiving discovery (UDP) packets */
00995         if (ssdp_listener_start(sm))
00996                 goto fail;
00997 
00998         /* Set up for sending multicast */
00999         if (ssdp_open_multicast(sm) < 0)
01000                 goto fail;
01001 
01002         /*
01003          * Broadcast NOTIFY messages to let the world know we exist.
01004          * This is done via a state machine since the messages should not be
01005          * all sent out at once.
01006          */
01007         if (advertisement_state_machine_start(sm))
01008                 goto fail;
01009 
01010         return 0;
01011 
01012 fail:
01013         upnp_wps_device_stop(sm);
01014         return -1;
01015 }
01016 
01017 
01022 void upnp_wps_device_deinit(struct upnp_wps_device_sm *sm)
01023 {
01024         if (!sm)
01025                 return;
01026 
01027         upnp_wps_device_stop(sm);
01028 
01029         if (sm->peer.wps)
01030                 wps_deinit(sm->peer.wps);
01031         os_free(sm->root_dir);
01032         os_free(sm->desc_url);
01033         os_free(sm->ctx->ap_pin);
01034         os_free(sm->ctx);
01035         os_free(sm);
01036 }
01037 
01038 
01046 struct upnp_wps_device_sm *
01047 upnp_wps_device_init(struct upnp_wps_device_ctx *ctx, struct wps_context *wps,
01048                      void *priv)
01049 {
01050         struct upnp_wps_device_sm *sm;
01051 
01052         sm = os_zalloc(sizeof(*sm));
01053         if (!sm) {
01054                 wpa_printf(MSG_ERROR, "WPS UPnP: upnp_wps_device_init failed");
01055                 return NULL;
01056         }
01057 
01058         sm->ctx = ctx;
01059         sm->wps = wps;
01060         sm->priv = priv;
01061         dl_list_init(&sm->msearch_replies);
01062         dl_list_init(&sm->subscriptions);
01063 
01064         return sm;
01065 }
01066 
01067 
01073 int upnp_wps_subscribers(struct upnp_wps_device_sm *sm)
01074 {
01075         return !dl_list_empty(&sm->subscriptions);
01076 }


wpa_supplicant_node
Author(s): Package maintained by Blaise Gassend
autogenerated on Thu Jan 2 2014 11:25:15