digest: add support for OpenSSL 1.1.0

[siplcs.git] / src / core / sipe-lync-autodiscover.c

/**
 * @file sipe-lync-autodiscover.c
 *
 * pidgin-sipe
 *
 * Copyright (C) 2016-2017 SIPE Project <http://sipe.sourceforge.net/>
 *
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Specification references:
 *
 *   - [MS-OCDISCWS]: https://msdn.microsoft.com/en-us/library/hh623245.aspx
 *   - Understanding Autodiscover in Lync Server 2013
 *                    https://technet.microsoft.com/en-us/library/jj945654.aspx
 */

#include <string.h>

#include <glib.h>

#include "sipe-common.h"
#include "sipe-backend.h"
#include "sipe-core.h"
#include "sipe-core-private.h"
#include "sipe-http.h"
#include "sipe-lync-autodiscover.h"
#include "sipe-utils.h"
#include "sipe-svc.h"
#include "sipe-webticket.h"
#include "sipe-xml.h"

#define LYNC_AUTODISCOVER_ACCEPT_HEADER \
        "Accept: application/vnd.microsoft.rtc.autodiscover+xml;v=1\r\n"

struct lync_autodiscover_request {
        sipe_lync_autodiscover_callback *cb;
        gpointer cb_data;
        gpointer id;                       /* != NULL for active request */
        struct sipe_http_request *request;
        struct sipe_svc_session *session;
        const gchar *protocol;
        const gchar **method;
        gchar *uri;
        gboolean is_pending;
};

struct sipe_lync_autodiscover {
        GSList *pending_requests;
};

/* Use "lar" inside the code fragment */
#define FOR_ALL_REQUESTS_WITH_SAME_ID(code) \
        {                                                                   \
                GSList *entry = sipe_private->lync_autodiscover->pending_requests; \
                while (entry) {                                                    \
                        struct lync_autodiscover_request *lar = entry->data;       \
                        entry = entry->next;                                       \
                        if (lar->id == id) {                                       \
                                code;                                              \
                        }                                                          \
                }                                                                  \
        }

static void sipe_lync_autodiscover_request_free(struct sipe_core_private *sipe_private,
                                                struct lync_autodiscover_request *request)
{
        struct sipe_lync_autodiscover *sla = sipe_private->lync_autodiscover;

        sla->pending_requests = g_slist_remove(sla->pending_requests, request);

        if (request->request)
                sipe_http_request_cancel(request->request);
        if (request->cb)
                /* Callback: aborted */
                (*request->cb)(sipe_private, NULL, request->cb_data);
        sipe_svc_session_close(request->session);
        g_free(request->uri);
        g_free(request);
}

static void sipe_lync_autodiscover_cb(struct sipe_core_private *sipe_private,
                                      guint status,
                                      GSList *headers,
                                      const gchar *body,
                                      gpointer callback_data);
static void lync_request(struct sipe_core_private *sipe_private,
                         struct lync_autodiscover_request *request,
                         const gchar *uri,
                         const gchar *headers)
{
        request->request = sipe_http_request_get(sipe_private,
                                                 uri,
                                                 headers ? headers : LYNC_AUTODISCOVER_ACCEPT_HEADER,
                                                 sipe_lync_autodiscover_cb,
                                                 request);
}

static GSList *sipe_lync_autodiscover_add(GSList *servers,
                                          const sipe_xml *node,
                                          const gchar *name)
{
        const sipe_xml *child = sipe_xml_child(node, name);
        const gchar *fqdn = sipe_xml_attribute(child, "fqdn");
        guint port = sipe_xml_int_attribute(child, "port", 0);

        /* Add new entry to head of list */
        if (fqdn && (port != 0)) {
                struct sipe_lync_autodiscover_data *lync_data = g_new0(struct sipe_lync_autodiscover_data, 1);
                lync_data->server = g_strdup(fqdn);
                lync_data->port   = port;
                servers = g_slist_prepend(servers, lync_data);
        }

        return(servers);
}

GSList *sipe_lync_autodiscover_pop(GSList *servers)
{
        if (servers) {
                struct sipe_lync_autodiscover_data *lync_data = servers->data;
                servers = g_slist_remove(servers, lync_data);

                if (lync_data) {
                        g_free((gchar *) lync_data->server);
                        g_free(lync_data);
                }
        }

        return(servers);
}

static void sipe_lync_autodiscover_queue_request(struct sipe_core_private *sipe_private,
                                                 struct lync_autodiscover_request *request);
static void sipe_lync_autodiscover_parse(struct sipe_core_private *sipe_private,
                                         struct lync_autodiscover_request *request,
                                         const gchar *body)
{
        sipe_xml *xml = sipe_xml_parse(body, strlen(body));
        const sipe_xml *node;
        gboolean next = TRUE;
        const gchar *access_location;

        /* Root: resources exposed by this server */
        for (node = sipe_xml_child(xml, "Root/Link");
             node;
             node = sipe_xml_twin(node)) {
                const gchar *token = sipe_xml_attribute(node, "token");
                const gchar *uri = sipe_xml_attribute(node, "href");

                if (token && uri) {
                        /* Redirect? */
                        if (sipe_strcase_equal(token, "Redirect")) {
                                SIPE_DEBUG_INFO("sipe_lync_autodiscover_parse: redirect to %s",
                                                uri);
                                lync_request(sipe_private, request, uri, NULL);
                                next = FALSE;
                                break;

                        /* User? */
                        } else if (sipe_strcase_equal(token, "User")) {
                                SIPE_DEBUG_INFO("sipe_lync_autodiscover_parse: user %s",
                                                uri);

                                /* remember URI for authentication failure */
                                request->uri = g_strdup(uri);

                                lync_request(sipe_private, request, uri, NULL);
                                next = FALSE;
                                break;

                        } else
                                SIPE_DEBUG_INFO("sipe_lync_autodiscover_parse: unknown token %s",
                                                token);
                }
        }

        access_location = sipe_xml_attribute(xml, "AccessLocation");

        /* User: topology information of the user’s home server */
        if ((node = sipe_xml_child(xml, "User")) != NULL) {
                gpointer id = request->id;

                /* Active request? */
                if (id) {
                        GSList *servers;

                        /* List is reversed, i.e. internal will be tried first */
                        servers = g_slist_prepend(NULL, NULL);

                        if (!access_location ||
                            sipe_strcase_equal(access_location, "external")) {
                                servers = sipe_lync_autodiscover_add(servers,
                                                                     node,
                                                                     "SipClientExternalAccess");
                        }

                        if (!access_location ||
                            sipe_strcase_equal(access_location, "internal")) {
                                servers = sipe_lync_autodiscover_add(servers,
                                                                     node,
                                                                     "SipClientInternalAccess");
                        }

                        /* Callback takes ownership of servers list */
                        (*request->cb)(sipe_private, servers, request->cb_data);

                        /* We're done with requests for this callback */
                        FOR_ALL_REQUESTS_WITH_SAME_ID( \
                                lar->cb = NULL;        \
                                lar->id = NULL         \
                        );

                }

                /* Request completed */
                next = FALSE;
                sipe_lync_autodiscover_request_free(sipe_private, request);
                /* request is invalid */
        }

        sipe_xml_free(xml);

        if (next)
                sipe_lync_autodiscover_queue_request(sipe_private, request);
}

static void sipe_lync_autodiscover_webticket(struct sipe_core_private *sipe_private,
                                             SIPE_UNUSED_PARAMETER const gchar *base_uri,
                                             const gchar *auth_uri,
                                             const gchar *wsse_security,
                                             SIPE_UNUSED_PARAMETER const gchar *failure_msg,
                                             gpointer callback_data)
{
        struct lync_autodiscover_request *request = callback_data;
        gchar *saml;

        /* Extract SAML Assertion from WSSE Security XML text */
        if (wsse_security &&
            ((saml = sipe_xml_extract_raw(wsse_security,
                                          "Assertion",
                                          TRUE)) != NULL)) {
                gchar *base64 = g_base64_encode((const guchar *) saml,
                                                strlen(saml));
                gchar *headers = g_strdup_printf(LYNC_AUTODISCOVER_ACCEPT_HEADER
                                                 "X-MS-WebTicket: opaque=%s\r\n",
                                                 base64);
                g_free(base64);

                SIPE_DEBUG_INFO("sipe_lync_autodiscover_webticket: got ticket for Auth URI %s",
                                auth_uri);
                g_free(saml);

                lync_request(sipe_private, request, auth_uri, headers);
                g_free(headers);

        } else
                sipe_lync_autodiscover_queue_request(sipe_private, request);
}

static void sipe_lync_autodiscover_cb(struct sipe_core_private *sipe_private,
                                      guint status,
                                      GSList *headers,
                                      const gchar *body,
                                      gpointer callback_data)
{
        struct lync_autodiscover_request *request = callback_data;
        const gchar *type = sipe_utils_nameval_find(headers, "Content-Type");
        gchar *uri = request->uri;

        request->request = NULL;
        request->uri     = NULL;

        switch (status) {
        case SIPE_HTTP_STATUS_OK:
                /* only accept Autodiscover XML responses */
                if (body && g_str_has_prefix(type, "application/vnd.microsoft.rtc.autodiscover+xml"))
                        sipe_lync_autodiscover_parse(sipe_private, request, body);
                else
                        sipe_lync_autodiscover_queue_request(sipe_private, request);
                break;

        case SIPE_HTTP_STATUS_FAILED:
                {
                        if (uri) {
                                /* check for authentication failure */
                                const gchar *webticket_uri = sipe_utils_nameval_find(headers,
                                                                                     "X-MS-WebTicketURL");

                                if (!(webticket_uri &&
                                      sipe_webticket_request_with_auth(sipe_private,
                                                                       request->session,
                                                                       webticket_uri,
                                                                       uri, /* Auth URI */
                                                                       sipe_lync_autodiscover_webticket,
                                                                       request)))
                                        sipe_lync_autodiscover_queue_request(sipe_private, request);
                        } else
                                sipe_lync_autodiscover_queue_request(sipe_private, request);
                }
                break;

        case SIPE_HTTP_STATUS_ABORTED:
                /* we are not allowed to generate new requests */
                sipe_lync_autodiscover_request_free(sipe_private, request);
                break;

        default:
                sipe_lync_autodiscover_queue_request(sipe_private, request);
                break;
        }

        g_free(uri);
}

/* Proceed to next method for request */
static void sipe_lync_autodiscover_request(struct sipe_core_private *sipe_private,
                                           struct lync_autodiscover_request *request)
{
        gpointer id = request->id;

        /* Active request? */
        if (id) {
                static const gchar *methods[] = {
                        "%s://LyncDiscoverInternal.%s/?sipuri=%s",
                        "%s://LyncDiscover.%s/?sipuri=%s",
                        NULL
                };

                request->is_pending = TRUE;

                if (request->method)
                        request->method++;
                else
                        request->method = methods;

                if (*request->method) {
                        gchar *uri = g_strdup_printf(*request->method,
                                                     request->protocol,
                                                     SIPE_CORE_PUBLIC->sip_domain,
                                                     sipe_private->username);

                        SIPE_DEBUG_INFO("sipe_lync_autodiscover_request: trying '%s'", uri);

                        lync_request(sipe_private, request, uri, NULL);
                        g_free(uri);

                } else {
                        guint count = 0;

                        /* Count entries with the same request ID */
                        FOR_ALL_REQUESTS_WITH_SAME_ID( \
                                count++;               \
                        );

                        if (count == 1) {
                                /*
                                 * This is the last pending request for this
                                 * ID, i.e. autodiscover has failed. Create
                                 * empty server list and return it.
                                 */
                                GSList *servers = g_slist_prepend(NULL, NULL);

                                /* All methods tried, indicate failure to caller */
                                SIPE_DEBUG_INFO_NOFORMAT("sipe_lync_autodiscover_request: no more methods to try!");

                                /* Callback takes ownership of servers list */
                                (*request->cb)(sipe_private, servers, request->cb_data);
                        }

                        /* Request completed */
                        request->cb = NULL;
                        sipe_lync_autodiscover_request_free(sipe_private, request);
                        /* request is invalid */
                }
        } else {
                /* Inactive request, callback already NULL */
                sipe_lync_autodiscover_request_free(sipe_private, request);
                /* request is invalid */
        }
}

/* Proceed to next method for all requests */
static void sipe_lync_autodiscover_queue_request(struct sipe_core_private *sipe_private,
                                                 struct lync_autodiscover_request *request)
{
        gpointer id = request->id;

        /* This request is ready to proceed to next method */
        request->is_pending = FALSE;

        /* Is any request for the same ID still pending? */
        FOR_ALL_REQUESTS_WITH_SAME_ID( \
                if (lar->is_pending)   \
                        return         \
        );

        SIPE_DEBUG_INFO_NOFORMAT("sipe_lync_autodiscover_queue_request: proceed in lockstep");

        /* No, proceed to next method for all requests */
        FOR_ALL_REQUESTS_WITH_SAME_ID(                       \
                sipe_lync_autodiscover_request(sipe_private, \
                                               lar)          \
        );
}

static gpointer sipe_lync_autodiscover_create(struct sipe_core_private *sipe_private,
                                              gpointer id,
                                              const gchar *protocol,
                                              sipe_lync_autodiscover_callback *callback,
                                              gpointer callback_data)
{
        struct sipe_lync_autodiscover *sla = sipe_private->lync_autodiscover;
        struct lync_autodiscover_request *request = g_new0(struct lync_autodiscover_request, 1);

        /* use address of first request structure as unique ID */
        if (id == NULL)
                id = request;

        request->protocol = protocol;
        request->cb       = callback;
        request->cb_data  = callback_data;
        request->id       = id;
        request->session  = sipe_svc_session_start();

        sla->pending_requests = g_slist_prepend(sla->pending_requests,
                                                request);

        sipe_lync_autodiscover_request(sipe_private, request);

        return(id);
}

void sipe_lync_autodiscover_start(struct sipe_core_private *sipe_private,
                                  sipe_lync_autodiscover_callback *callback,
                                  gpointer callback_data)
{
        gpointer id = NULL;

#define CREATE(protocol) \
        id = sipe_lync_autodiscover_create(sipe_private,  \
                                           id,            \
                                           #protocol,     \
                                           callback,      \
                                           callback_data)
        CREATE(http);
        CREATE(https);
}

void sipe_lync_autodiscover_init(struct sipe_core_private *sipe_private)
{
        struct sipe_lync_autodiscover *sla = g_new0(struct sipe_lync_autodiscover, 1);

        sipe_private->lync_autodiscover = sla;
}

void sipe_lync_autodiscover_free(struct sipe_core_private *sipe_private)
{
        struct sipe_lync_autodiscover *sla = sipe_private->lync_autodiscover;

        while (sla->pending_requests)
                sipe_lync_autodiscover_request_free(sipe_private,
                                                    sla->pending_requests->data);

        g_free(sla);
        sipe_private->lync_autodiscover = NULL;
}

/*
  Local Variables:
  mode: c
  c-file-style: "bsd"
  indent-tabs-mode: t
  tab-width: 8
  End:
*/