Fix CI errors

sesman/libscp/libscp_session.c

@@ -63,6 +63,10 @@ scp_session_set_type(struct SCP_SESSION *s, tui8 type)
             s->type = SCP_SESSION_TYPE_XVNC;
             break;
 
+        case SCP_SESSION_TYPE_RESIZABLE_XVNC:
+            s->type = SCP_SESSION_TYPE_RESIZABLE_XVNC;
+            break;
+
         case SCP_SESSION_TYPE_XRDP:
             s->type = SCP_SESSION_TYPE_XRDP;
             break;

sesman/libscp/libscp_types.h

@@ -38,15 +38,16 @@
 #define SCP_RESOURCE_SHARING_REQUEST_YES 0x01
 #define SCP_RESOURCE_SHARING_REQUEST_NO  0x00
 
-#define SCP_SESSION_TYPE_XVNC    0x00
-#define SCP_SESSION_TYPE_XRDP    0x01
-#define SCP_SESSION_TYPE_MANAGE  0x02
-#define SCP_SESSION_TYPE_XORG    0x03
+#define SCP_SESSION_TYPE_XVNC              0x00
+#define SCP_SESSION_TYPE_XRDP              0x01
+#define SCP_SESSION_TYPE_MANAGE            0x02
+#define SCP_SESSION_TYPE_XORG              0x03
 
 /* SCP_GW_AUTHENTICATION can be used when XRDP + sesman act as a gateway
  * XRDP sends this command to let sesman verify if the user is allowed
  * to use the gateway */
-#define SCP_GW_AUTHENTICATION    0x04
+#define SCP_GW_AUTHENTICATION              0x04
+#define SCP_SESSION_TYPE_RESIZABLE_XVNC    0x05
 
 #define SCP_ADDRESS_TYPE_IPV4 0x00
 #define SCP_ADDRESS_TYPE_IPV6 0x01

sesman/libscp/libscp_v0.c

@@ -56,6 +56,10 @@ scp_v0c_connect(struct SCP_CONNECTION *c, struct SCP_SESSION *s)
     {
         out_uint16_be(c->out_s, 0);
     }
+    else if (s->type == SCP_SESSION_TYPE_RESIZABLE_XVNC)
+    {
+        out_uint16_be(c->out_s, 1);
+    }
     else if (s->type == SCP_SESSION_TYPE_XRDP)
     {
         out_uint16_be(c->out_s, 10);
@@ -199,7 +203,7 @@ scp_v0s_accept(struct SCP_CONNECTION *c, struct SCP_SESSION **s, int skipVchk)
 
     in_uint16_be(c->in_s, code);
 
-    if (code == 0 || code == 10 || code == 20)
+    if (code == 0 || code == 1 || code == 10 || code == 20)
     {
         session = scp_session_create();
 
@@ -215,6 +219,10 @@ scp_v0s_accept(struct SCP_CONNECTION *c, struct SCP_SESSION **s, int skipVchk)
         {
             scp_session_set_type(session, SCP_SESSION_TYPE_XVNC);
         }
+        else if (code == 1)
+        {
+            scp_session_set_type(session, SCP_SESSION_TYPE_RESIZABLE_XVNC);
+        }
         else if (code == 10)
         {
             scp_session_set_type(session, SCP_SESSION_TYPE_XRDP);

sesman/scp_v0.c

@@ -120,7 +120,8 @@ scp_v0_process(struct SCP_CONNECTION *c, struct SCP_SESSION *s)
                                 "username %s", s->username);
                 }
 
-                if (SCP_SESSION_TYPE_XVNC == s->type)
+                if (SCP_SESSION_TYPE_XVNC == s->type ||
+                    SCP_SESSION_TYPE_RESIZABLE_XVNC == s->type)
                 {
                     log_message( LOG_LEVEL_INFO, "starting Xvnc session...");
                     display = session_start(data, SESMAN_SESSION_TYPE_XVNC, c, s);

sesman/scp_v1.c

@@ -124,7 +124,8 @@ scp_v1_process(struct SCP_CONNECTION *c, struct SCP_SESSION *s)
             log_message(LOG_LEVEL_INFO, "++ created session (access granted): username %s", s->username);
         }
 
-        if (SCP_SESSION_TYPE_XVNC == s->type)
+        if (SCP_SESSION_TYPE_XVNC == s->type ||
+            SCP_SESSION_TYPE_RESIZABLE_XVNC == s->type)
         {
             log_message(LOG_LEVEL_INFO, "starting Xvnc session...");
             display = session_start(data, SESMAN_SESSION_TYPE_XVNC, c, s);

sesman/session.c

@@ -105,10 +105,13 @@ session_get_bydata(const char *name, int width, int height, int bpp, int type,
     {
         case SCP_SESSION_TYPE_XVNC: /* 0 */
             type = SESMAN_SESSION_TYPE_XVNC; /* 2 */
-            /* Xvnc cannot resize */
+            /* standard Xvnc can never resize */
             policy = (enum SESMAN_CFG_SESS_POLICY)
                      (policy | SESMAN_CFG_SESS_POLICY_D);
             break;
+        case SCP_SESSION_TYPE_RESIZABLE_XVNC:
+            type = SESMAN_SESSION_TYPE_XVNC;
+            break;
         case SCP_SESSION_TYPE_XRDP: /* 1 */
             type = SESMAN_SESSION_TYPE_XRDP; /* 1 */
             break;

sesman/tools/sesrun.c

@@ -31,6 +31,10 @@
 #include "sesman.h"
 #include "tcp.h"
 
+#if !defined(PACKAGE_VERSION)
+#define PACKAGE_VERSION "???"
+#endif
+
 struct config_sesman g_cfg; /* config.h */
 
 /******************************************************************************/
@@ -61,10 +65,14 @@ main(int argc, char **argv)
 
     if (argc == 1)
     {
-        g_printf("xrdp session starter v0.1\n");
+        g_printf("xrdp session starter v" PACKAGE_VERSION "\n");
         g_printf("\nusage:\n");
-        g_printf("sesrun <server> <username> <password> <width> <height> <bpp> <session_cod>\n");
-        g_printf("session code 0 for Xvnc, 10 for X11RDP, 20 for Xorg\n");
+        g_printf("sesrun <server> <username> <password> <width> <height> <bpp> <session_code>\n");
+        g_printf("session code:-\n");
+        g_printf(" -  0 for fixed Xvnc\n");
+        g_printf(" -  1 for resizeable Xvnc\n");
+        g_printf(" - 10 for X11RDP\n");
+        g_printf(" - 20 for Xorg\n");
     }
     else if (argc == 8)
     {

vnc/vnc.c

@@ -16,6 +16,14 @@
  * limitations under the License.
  *
  * libvnc
+ *
+ * The message definitions used in this source file can be found mostly
+ * in RFC6143 - "The Remote Framebuffer Protocol".
+ *
+ * The ExtendedDesktopSize encoding is reserved in RFC6143, but not
+ * documented there. It is documented by the RFB protocol community
+ * wiki currently held at https://github.com/rfbproto/rfbroto. This is
+ * referred to below as the "RFB community wiki"
  */
 
 #if defined(HAVE_CONFIG_H)
@@ -26,21 +34,29 @@
 #include "log.h"
 #include "trans.h"
 #include "ssl_calls.h"
+#include "xrdp_client_info.h"
 
 #define LLOG_LEVEL 1
 #define LLOGLN(_level, _args) \
-  do \
-  { \
-    if (_level < LLOG_LEVEL) \
+    do \
     { \
-        g_write("xrdp:vnc [%10.10u]: ", g_time3()); \
-        g_writeln _args ; \
+        if (_level < LLOG_LEVEL) \
+        { \
+            g_write("xrdp:vnc [%10.10u]: ", g_time3()); \
+            g_writeln _args ; \
+        } \
     } \
-  } \
-  while (0)
+    while (0)
 
 #define AS_LOG_MESSAGE log_message
 
+/* Encodings and pseudo-encodings from RFC6143 */
+#define ENC_RAW                   0
+#define ENC_COPY_RECT             1
+#define ENC_CURSOR                (unsigned int)-239
+#define ENC_DESKTOP_SIZE          (unsigned int)-223
+#define ENC_EXTENDED_DESKTOP_SIZE (unsigned int)-308
+
 static int
 lib_mod_process_message(struct vnc *v, struct stream *s);
 
@@ -256,6 +272,356 @@ lib_process_channel_data(struct vnc *v, int chanid, int flags, int size,
 }
 
 /******************************************************************************/
+static void
+log_debug_screen_layout(const char *source,
+                        const struct vnc_screen_layout *layout)
+{
+    unsigned int i;
+    char text[256];
+    size_t pos;
+    int res;
+
+    pos = 0;
+    res = g_snprintf(text, sizeof(text) - pos,
+                     "Layout from %s (#screens=%d) :",
+                     source, layout->count);
+
+    i = 0;
+    while (res > 0 && (size_t)res < sizeof(text) - pos && i < layout->count)
+    {
+        pos += res;
+        res = g_snprintf(&text[pos], sizeof(text) - pos,
+                         " %d:(%dx%d+%d+%d)",
+                         layout->s[i].id,
+                         layout->s[i].width, layout->s[i].height,
+                         layout->s[i].x, layout->s[i].y);
+        ++i;
+    }
+    log_message(LOG_LEVEL_DEBUG, "%s", text);
+}
+
+/*****************************************************************************
+ * Compares two vnc_screen structures, returning a value which can
+ * also be used for sorting on id
+ */
+static int cmp_vnc_screen(const struct vnc_screen *a,
+                          const struct vnc_screen *b)
+{
+    int result = 0;
+    if (a->id != b->id)
+    {
+        result = a->id - b->id;
+    }
+    else if (a->x != b->x)
+    {
+        result = a->x - b->x;
+    }
+    else if (a->y != b->y)
+    {
+        result = a->y - b->y;
+    }
+    else if (a->width != b->width)
+    {
+        result = a->width - b->width;
+    }
+    else if (a->height != b->height)
+    {
+        result = a->height - b->height;
+    }
+
+    return result;
+}
+
+
+/*****************************************************************************
+ * Compares two vnc_screen_layout structures
+ *
+ * Result can only be used for equality testing
+ */
+static int cmp_vnc_screen_layout(const struct vnc_screen_layout *a,
+                                 const struct vnc_screen_layout *b)
+{
+    unsigned int i;
+    int result = b->count - a->count;
+
+    for (i = 0 ; result == 0 && i < a->count ; ++i)
+    {
+        result = cmp_vnc_screen(&a->s[i], &b->s[i]);
+    }
+
+    return result;
+}
+
+
+/*****************************************************************************
+ * Reads an extended desktop size rectangle from the VNC server
+ *
+ * Returned structure is in increasing ID order, rather than order on-the-wire
+ *
+ * On a successful return, layout->s has been allocated, and must be
+ * freed after use.
+ */
+static int
+read_extended_desktop_size_rect(struct vnc *v,
+                                struct vnc_screen_layout *layout)
+{
+    struct stream *s;
+    int error;
+    unsigned int i;
+
+    layout->count = 0;
+
+    make_stream(s);
+    init_stream(s, 8192);
+
+    /* Read in the current screen config */
+    error = trans_force_read_s(v->trans, s, 4);
+    if (error == 0)
+    {
+        /* Get the number of screens */
+        in_uint8(s, layout->count);
+        in_uint8s(s, 3);
+
+        error = trans_force_read_s(v->trans, s, 16 * layout->count);
+        if (error == 0)
+        {
+            layout->s = g_new(struct vnc_screen, layout->count);
+            if (layout->s == NULL)
+            {
+                log_message(LOG_LEVEL_ERROR,
+                            "VNC : Can't alloc for %d screens", layout->count);
+                layout->count = 0;
+                error = 1;
+            }
+            else
+            {
+                for (i = 0 ; i < layout->count ; ++i)
+                {
+                    in_uint32_be(s, layout->s[i].id);
+                    in_uint16_be(s, layout->s[i].x);
+                    in_uint16_be(s, layout->s[i].y);
+                    in_uint16_be(s, layout->s[i].width);
+                    in_uint16_be(s, layout->s[i].height);
+                    in_uint32_be(s, layout->s[i].flags);
+                }
+            }
+
+            /*  sort monitors in increasing ID order */
+            qsort(layout->s, layout->count, sizeof(layout->s[0]),
+                  (int (*)(const void *, const void *))cmp_vnc_screen);
+        }
+    }
+
+    free_stream(s);
+
+    return error;
+}
+
+/*****************************************************************************
+ * Check to see if a SetDesktopSize message should be sent, based on the
+ * current Xvnc geometry and screen layout
+ */
+static int
+set_desktop_size_is_needed(struct vnc *v, int vnc_width, int vnc_height,
+                           const struct vnc_screen_layout *vnc_layout)
+{
+    int result = 0;
+
+    if (v->mod_width != vnc_width || v->mod_height != vnc_height)
+    {
+        log_message(LOG_LEVEL_DEBUG, "VNC SetDesktopSize needed "
+                    "for size change from (%d,%d) to (%d,%d)",
+                    vnc_width, vnc_height, v->mod_width, v->mod_height);
+        result = 1;
+    }
+    else if (cmp_vnc_screen_layout(vnc_layout, &v->screen_layout) != 0)
+    {
+        log_message(LOG_LEVEL_DEBUG, "VNC SetDesktopSize needed "
+                    "for changed screen layouts");
+        result = 1;
+    }
+    else
+    {
+        log_message(LOG_LEVEL_DEBUG, "VNC SetDesktopSize not needed");
+    }
+
+    return result;
+}
+
+/*****************************************************************************
+ * Send a SetDesktopSize message based on the initial RDP parameters
+ */
+static int
+send_set_desktop_size_msg(struct vnc *v)
+{
+    unsigned int i;
+    struct stream *s;
+    int error;
+
+    make_stream(s);
+    init_stream(s, 8192);
+    out_uint8(s, 251);
+    out_uint8(s, 0);
+    out_uint16_be(s, v->mod_width);
+    out_uint16_be(s, v->mod_height);
+
+    out_uint8(s, v->screen_layout.count);
+    out_uint8(s, 0);
+    for (i = 0 ; i < v->screen_layout.count ; ++i)
+    {
+        out_uint32_be(s, v->screen_layout.s[i].id);
+        out_uint16_be(s, v->screen_layout.s[i].x);
+        out_uint16_be(s, v->screen_layout.s[i].y);
+        out_uint16_be(s, v->screen_layout.s[i].width);
+        out_uint16_be(s, v->screen_layout.s[i].height);
+        out_uint32_be(s, v->screen_layout.s[i].flags);
+    }
+    s_mark_end(s);
+    log_message(LOG_LEVEL_DEBUG, "VNC Sending SetDesktopSize");
+    error = lib_send_copy(v, s);
+    free_stream(s);
+
+    return error;
+}
+
+/*****************************************************************************
+ * Check to resize the attached client
+ *
+ * The resizing of multi-screen layouts isn't supported. If
+ * we end up in this situation we currently throw an error, resulting in
+ * a disconnect.
+ */
+static int
+check_to_resize_client(struct vnc *v, int width, int height,
+                       const struct vnc_screen_layout *layout)
+{
+    int error = 0;
+
+    if (width != v->mod_width || height != v->mod_height ||
+            cmp_vnc_screen_layout(&v->screen_layout, layout) != 0)
+    {
+        /*
+         * we don't have the capability to cope with a rearrangement
+         * of a multi-screen layout.
+         */
+        if (layout->count != 1 || v->screen_layout.count != 1)
+        {
+            char text[256];
+            g_sprintf(text, "VNC Resize to %d screen(s) from %d screen(s) "
+                      "not implemented",
+                      v->screen_layout.count, layout->count);
+            v->server_msg(v, text, 0);
+
+            /* Dump some useful info, in case we get here when we don't
+             * need to */
+            log_debug_screen_layout("OldLayout", layout);
+            log_debug_screen_layout("NewLayout", layout);
+            error = 1;
+        }
+        else
+        {
+            v->mod_width = width;
+            v->mod_height = height;
+            v->screen_layout.s[0] = layout->s[0];
+            error = v->server_reset(v, width, height, v->mod_bpp);
+        }
+    }
+    return error;
+}
+
+/*****************************************************************************
+ * Process an ExtendedDesktopSize message
+ */
+static int
+process_extended_desktop_size(struct vnc *v, int x, int y, int cx, int cy,
+                              const struct vnc_screen_layout *layout)
+{
+    int error = 0;
+
+    switch (x)
+    {
+        default:
+            /* Spec says to treat unknown values as a zero */
+            if (x != 0)
+            {
+                log_message(LOG_LEVEL_ERROR,
+                            "VNC got ExtendedDesktopSize rectangle type %d", x);
+            }
+
+            if (v->first_framebuffer_update)
+            {
+                /*
+                 * This is a response to our first framebuffer update
+                 * request.  At this point, we want to impose our will
+                 * on the client.  After that, the server may request
+                 * size changes of its own.
+                 */
+                log_message(LOG_LEVEL_DEBUG,
+                            "VNC got first ExtendedDesktopSize rectangle "
+                            "x=%d, y=%d, cx=%d, cy=%d", x, y, cx, cy);
+                log_debug_screen_layout("Xvnc", layout);
+
+                /*
+                 * If we've only got one screen, and the other side has
+                 * only got one screen, we will preserve their screen
+                 * ID and any flags.  This may prevent us sending
+                 * an unwanted SetDesktopSize message if the screen
+                 * dimensions are a match. We can't do this with more than
+                 * one screen, as we have no way to map different IDs
+                 */
+                if (layout->count == 1 && v->screen_layout.count == 1)
+                {
+                    log_message(LOG_LEVEL_DEBUG, "VNC "
+                                "setting screen id to %d from server",
+                                layout->s[0].id);
+
+                    v->screen_layout.s[0].id = layout->s[0].id;
+                    v->screen_layout.s[0].flags = layout->s[0].flags;
+                }
+                if (set_desktop_size_is_needed(v, cx, cy, layout))
+                {
+                    error = send_set_desktop_size_msg(v);
+                    v->set_desktop_size_in_progress = 1;
+                }
+            }
+            else if (v->set_desktop_size_in_progress)
+            {
+                /* Ignore this, until the X server has responded */
+            }
+            else
+            {
+                /* Could be a response to another framebuffer update request,
+                 * or a server-side change (i.e. with xrandr)
+                 */
+                error = check_to_resize_client(v, cx, cy, layout);
+            }
+            break;
+
+        case 1: /* Response to a SetDesktopSize message from us */
+            v->set_desktop_size_in_progress = 0;
+            if (y == 0)
+            {
+                log_message(LOG_LEVEL_DEBUG,
+                            "VNC SetDesktopSize was successful");
+            }
+            else
+            {
+                log_message(LOG_LEVEL_ERROR,
+                            "VNC SetDesktopSize failed and returned %d", y);
+            }
+            break;
+
+        case 2:
+            /*
+             * Another client has resized or re-arranged the screen
+             */
+            error = check_to_resize_client(v, cx, cy, layout);
+            break;
+    }
+    return error;
+}
+
+/*****************************************************************************/
 int
 lib_mod_event(struct vnc *v, int msg, long param1, long param2,
               long param3, long param4)
@@ -385,7 +751,7 @@ lib_mod_event(struct vnc *v, int msg, long param1, long param2,
             /* FramebufferUpdateRequest */
             init_stream(s, 8192);
             out_uint8(s, 3);
-            out_uint8(s, 0);
+            out_uint8(s, 0); /* incremental == 0 : Full contents */
             x = (param1 >> 16) & 0xffff;
             out_uint16_be(s, x);
             y = param1 & 0xffff;
@@ -615,6 +981,8 @@ lib_framebuffer_update(struct vnc *v)
     int need_size;
     struct stream *s;
     struct stream *pixel_s;
+    int extended_desktop_size_msg_received = 0;
+    struct vnc_screen_layout layout = { 0 };
 
     num_recs = 0;
     Bpp = (v->mod_bpp + 7) / 8;
@@ -655,7 +1023,7 @@ lib_framebuffer_update(struct vnc *v)
             in_uint16_be(s, cy);
             in_uint32_be(s, encoding);
 
-            if (encoding == 0) /* raw */
+            if (encoding == ENC_RAW)
             {
                 need_size = cx * cy * Bpp;
                 init_stream(pixel_s, need_size);
@@ -666,7 +1034,7 @@ lib_framebuffer_update(struct vnc *v)
                     error = v->server_paint_rect(v, x, y, cx, cy, pixel_s->data, cx, cy, 0, 0);
                 }
             }
-            else if (encoding == 1) /* copy rect */
+            else if (encoding == ENC_COPY_RECT)
             {
                 init_stream(s, 8192);
                 error = trans_force_read_s(v->trans, s, 4);
@@ -678,7 +1046,7 @@ lib_framebuffer_update(struct vnc *v)
                     error = v->server_screen_blt(v, x, y, cx, cy, srcx, srcy);
                 }
             }
-            else if (encoding == 0xffffff11) /* cursor */
+            else if (encoding == ENC_CURSOR)
             {
                 g_memset(cursor_data, 0, 32 * (32 * 3));
                 g_memset(cursor_mask, 0, 32 * (32 / 8));
@@ -723,12 +1091,24 @@ lib_framebuffer_update(struct vnc *v)
                     error = v->server_set_cursor(v, x, y, cursor_data, cursor_mask);
                 }
             }
-            else if (encoding == 0xffffff21) /* desktop size */
+            else if (encoding == ENC_DESKTOP_SIZE)
             {
+                /* Only received for non-resizeable desktops */
                 v->mod_width = cx;
                 v->mod_height = cy;
                 error = v->server_reset(v, cx, cy, v->mod_bpp);
             }
+            else if (encoding == ENC_EXTENDED_DESKTOP_SIZE)
+            {
+                extended_desktop_size_msg_received  = 1;
+                error = read_extended_desktop_size_rect(v, &layout);
+                if (error == 0)
+                {
+                    error = process_extended_desktop_size(v, x, y, cx, cy,
+                                                          &layout);
+                    g_free(layout.s);
+                }
+            }
             else
             {
                 g_sprintf(text, "VNC error in lib_framebuffer_update encoding = %8.8x",
@@ -743,6 +1123,20 @@ lib_framebuffer_update(struct vnc *v)
         error = v->server_end_update(v);
     }
 
+    if (v->first_framebuffer_update)
+    {
+        v->first_framebuffer_update = 0;
+        if (v->resizeable_mode && !extended_desktop_size_msg_received)
+        {
+            log_message(LOG_LEVEL_ERROR, "Resizeable mode requested, "
+                        "but X server does not support it");
+            if (error == 0)
+            {
+                error = 1;
+            }
+        }
+    }
+
     if (error == 0)
     {
         if (v->suppress_output == 0)
@@ -750,7 +1144,7 @@ lib_framebuffer_update(struct vnc *v)
             /* FramebufferUpdateRequest */
             init_stream(s, 8192);
             out_uint8(s, 3);
-            out_uint8(s, 1);
+            out_uint8(s, 1); /* incremental == 1 : Changes only */
             out_uint16_be(s, 0);
             out_uint16_be(s, 0);
             out_uint16_be(s, v->mod_width);
@@ -1026,7 +1420,7 @@ lib_mod_connect(struct vnc *v)
         default:
             v->server_msg(v, "VNC error - only supporting 8, 15, 16, 24 and 32 "
                           "bpp rdp connections", 0);
-        return 1;
+            return 1;
     }
 
     if (g_strcmp(v->ip, "") == 0)
@@ -1055,7 +1449,7 @@ lib_mod_connect(struct vnc *v)
         v->server_msg(v, text, 0);
         g_sleep(v->delay_ms);
     }
-    
+
     g_sprintf(text, "VNC connecting to %s %s", v->ip, con_port);
     v->server_msg(v, text, 0);
 
@@ -1188,8 +1582,14 @@ lib_mod_connect(struct vnc *v)
 
     if (error == 0)
     {
-        in_uint16_be(s, v->mod_width);
-        in_uint16_be(s, v->mod_height);
+        /* In resizeable mode, we're not interested at this stage how
+         * big the X server is, as we're going to go for the size set
+         * by the "client_info" param */
+        if (!v->resizeable_mode)
+        {
+            in_uint16_be(s, v->mod_width);
+            in_uint16_be(s, v->mod_height);
+        }
         init_stream(pixel_format, 8192);
         v->server_msg(v, "VNC receiving pixel format", 0);
         error = trans_force_read_s(v->trans, pixel_format, 16);
@@ -1329,11 +1729,20 @@ lib_mod_connect(struct vnc *v)
         init_stream(s, 8192);
         out_uint8(s, 2);
         out_uint8(s, 0);
-        out_uint16_be(s, 4);
-        out_uint32_be(s, 0); /* raw */
-        out_uint32_be(s, 1); /* copy rect */
-        out_uint32_be(s, 0xffffff11); /* cursor */
-        out_uint32_be(s, 0xffffff21); /* desktop size */
+        out_uint16_be(s, 4); /* Number of encodings following */
+        out_uint32_be(s, ENC_RAW);
+        out_uint32_be(s, ENC_COPY_RECT);
+        out_uint32_be(s, ENC_CURSOR);
+        if (v->resizeable_mode)
+        {
+            v->server_msg(v, "VNC with ExtendedDesktopSize pseudo-encoding", 0);
+            out_uint32_be(s, ENC_EXTENDED_DESKTOP_SIZE);
+        }
+        else
+        {
+            v->server_msg(v, "VNC with DesktopSize pseudo-encoding", 0);
+            out_uint32_be(s, ENC_DESKTOP_SIZE);
+        }
         v->server_msg(v, "VNC sending encodings", 0);
         s_mark_end(s);
         error = trans_force_write_s(v->trans, s);
@@ -1344,6 +1753,7 @@ lib_mod_connect(struct vnc *v)
         error = v->server_reset(v, v->mod_width, v->mod_height, v->mod_bpp);
     }
 
+    v->first_framebuffer_update = 1;
     if (error == 0)
     {
         if (v->suppress_output == 0)
@@ -1351,7 +1761,7 @@ lib_mod_connect(struct vnc *v)
             /* FramebufferUpdateRequest */
             init_stream(s, 8192);
             out_uint8(s, 3);
-            out_uint8(s, 0);
+            out_uint8(s, 0); /* incremental == 0 : Full contents */
             out_uint16_be(s, 0);
             out_uint16_be(s, 0);
             out_uint16_be(s, v->mod_width);
@@ -1459,6 +1869,57 @@ lib_mod_set_param(struct vnc *v, const char *name, const char *value)
         v->got_guid = 1;
         g_memcpy(v->guid, value, 16);
     }
+    else if (g_strcasecmp(name, "code") == 0)
+    {
+        v->resizeable_mode = (g_atoi(value) == 1);
+    }
+    else if (g_strcasecmp(name, "client_info") == 0)
+    {
+        const struct xrdp_client_info *client_info =
+            (const struct xrdp_client_info *) value;
+
+        g_free(v->screen_layout.s);
+
+        /* The RDP client (width,height) is requested for the X server
+         * later on if we're in resizeable mode. If we're not, these
+         * settings will be overwritten later by the ServerInit
+         * message from the X server */
+        v->mod_width = client_info->width;
+        v->mod_height = client_info->height;
+
+        /* Save info needed for resizeable support */
+        if (!client_info->multimon || client_info->monitorCount < 1)
+        {
+            v->screen_layout.count = 1;
+            v->screen_layout.s = g_new(struct vnc_screen, 1);
+            v->screen_layout.s[0].id = 0;
+            v->screen_layout.s[0].x = 0;
+            v->screen_layout.s[0].y = 0;
+            v->screen_layout.s[0].width = client_info->width;
+            v->screen_layout.s[0].height = client_info->height;
+            v->screen_layout.s[0].flags = 0;
+        }
+        else
+        {
+            int i;
+            v->screen_layout.count = client_info->monitorCount;
+            v->screen_layout.s = g_new(struct vnc_screen,
+                                       v->screen_layout.count);
+            for (i = 0 ; i < client_info->monitorCount ; ++i)
+            {
+                v->screen_layout.s[i].id = i;
+                v->screen_layout.s[i].x = client_info->minfo[i].left;
+                v->screen_layout.s[i].y = client_info->minfo[i].top;
+                v->screen_layout.s[i].width =  client_info->minfo[i].right -
+                                               client_info->minfo[i].left + 1;
+                v->screen_layout.s[i].height = client_info->minfo[i].bottom -
+                                               client_info->minfo[i].top + 1;
+                v->screen_layout.s[i].flags = 0;
+            }
+        }
+        log_debug_screen_layout("client_info", &v->screen_layout);
+    }
+
 
     return 0;
 }
@@ -1504,7 +1965,7 @@ lib_mod_check_wait_objs(struct vnc *v)
 /******************************************************************************/
 /* return error */
 int
-lib_mod_frame_ack(struct vnc* v, int flags, int frame_id)
+lib_mod_frame_ack(struct vnc *v, int flags, int frame_id)
 {
     return 0;
 }
@@ -1512,7 +1973,7 @@ lib_mod_frame_ack(struct vnc* v, int flags, int frame_id)
 /******************************************************************************/
 /* return error */
 int
-lib_mod_suppress_output(struct vnc* v, int suppress,
+lib_mod_suppress_output(struct vnc *v, int suppress,
                         int left, int top, int right, int bottom)
 {
     int error;
@@ -1526,7 +1987,7 @@ lib_mod_suppress_output(struct vnc* v, int suppress,
         make_stream(s);
         init_stream(s, 8192);
         out_uint8(s, 3);
-        out_uint8(s, 0);
+        out_uint8(s, 0); /* incremental == 0 : Full contents */
         out_uint16_be(s, 0);
         out_uint16_be(s, 0);
         out_uint16_be(s, v->mod_width);
@@ -1575,5 +2036,6 @@ mod_exit(tintptr handle)
     }
     trans_delete(v->trans);
     g_free(v);
+    g_free(v->screen_layout.s);
     return 0;
 }

vnc/vnc.h

@@ -26,98 +26,121 @@
 
 #define CURRENT_MOD_VER 4
 
+/* Screen used for ExtendedDesktopSize / Set DesktopSize */
+struct vnc_screen
+{
+    int id;
+    int x;
+    int y;
+    int width;
+    int height;
+    int flags;
+};
+
+struct vnc_screen_layout
+{
+    unsigned int count;
+    /* For comparison, screens are sorted in increasing order of ID */
+    struct vnc_screen *s;
+};
+
 struct vnc
 {
-  int size; /* size of this struct */
-  int version; /* internal version */
-  /* client functions */
-  int (*mod_start)(struct vnc* v, int w, int h, int bpp);
-  int (*mod_connect)(struct vnc* v);
-  int (*mod_event)(struct vnc* v, int msg, long param1, long param2,
-                   long param3, long param4);
-  int (*mod_signal)(struct vnc* v);
-  int (*mod_end)(struct vnc* v);
-  int (*mod_set_param)(struct vnc *v, const char *name, const char *value);
-  int (*mod_session_change)(struct vnc* v, int, int);
-  int (*mod_get_wait_objs)(struct vnc* v, tbus* read_objs, int* rcount,
-                           tbus* write_objs, int* wcount, int* timeout);
-  int (*mod_check_wait_objs)(struct vnc* v);
-  int (*mod_frame_ack)(struct vnc* v, int flags, int frame_id);
-  int (*mod_suppress_output)(struct vnc* v, int suppress,
-                             int left, int top, int right, int bottom);
-  tintptr mod_dumby[100 - 11]; /* align, 100 minus the number of mod
+    int size; /* size of this struct */
+    int version; /* internal version */
+    /* client functions */
+    int (*mod_start)(struct vnc *v, int w, int h, int bpp);
+    int (*mod_connect)(struct vnc *v);
+    int (*mod_event)(struct vnc *v, int msg, long param1, long param2,
+                     long param3, long param4);
+    int (*mod_signal)(struct vnc *v);
+    int (*mod_end)(struct vnc *v);
+    int (*mod_set_param)(struct vnc *v, const char *name, const char *value);
+    int (*mod_session_change)(struct vnc *v, int, int);
+    int (*mod_get_wait_objs)(struct vnc *v, tbus *read_objs, int *rcount,
+                             tbus *write_objs, int *wcount, int *timeout);
+    int (*mod_check_wait_objs)(struct vnc *v);
+    int (*mod_frame_ack)(struct vnc *v, int flags, int frame_id);
+    int (*mod_suppress_output)(struct vnc *v, int suppress,
+                               int left, int top, int right, int bottom);
+    tintptr mod_dumby[100 - 11]; /* align, 100 minus the number of mod
                                   functions above */
-  /* server functions */
-  int (*server_begin_update)(struct vnc* v);
-  int (*server_end_update)(struct vnc* v);
-  int (*server_fill_rect)(struct vnc* v, int x, int y, int cx, int cy);
-  int (*server_screen_blt)(struct vnc* v, int x, int y, int cx, int cy,
-                           int srcx, int srcy);
-  int (*server_paint_rect)(struct vnc* v, int x, int y, int cx, int cy,
-                           char* data, int width, int height, int srcx, int srcy);
-  int (*server_set_cursor)(struct vnc* v, int x, int y, char* data, char* mask);
-  int (*server_palette)(struct vnc* v, int* palette);
-  int (*server_msg)(struct vnc* v, const char *msg, int code);
-  int (*server_is_term)(struct vnc* v);
-  int (*server_set_clip)(struct vnc* v, int x, int y, int cx, int cy);
-  int (*server_reset_clip)(struct vnc* v);
-  int (*server_set_fgcolor)(struct vnc* v, int fgcolor);
-  int (*server_set_bgcolor)(struct vnc* v, int bgcolor);
-  int (*server_set_opcode)(struct vnc* v, int opcode);
-  int (*server_set_mixmode)(struct vnc* v, int mixmode);
-  int (*server_set_brush)(struct vnc* v, int x_origin, int y_origin,
-                          int style, char* pattern);
-  int (*server_set_pen)(struct vnc* v, int style,
-                        int width);
-  int (*server_draw_line)(struct vnc* v, int x1, int y1, int x2, int y2);
-  int (*server_add_char)(struct vnc* v, int font, int character,
-                         int offset, int baseline,
-                         int width, int height, char* data);
-  int (*server_draw_text)(struct vnc* v, int font,
-                          int flags, int mixmode, int clip_left, int clip_top,
-                          int clip_right, int clip_bottom,
-                          int box_left, int box_top,
-                          int box_right, int box_bottom,
-                          int x, int y, char* data, int data_len);
-  int (*server_reset)(struct vnc* v, int width, int height, int bpp);
-  int (*server_query_channel)(struct vnc* v, int index,
-                              char* channel_name,
-                              int* channel_flags);
-  int (*server_get_channel_id)(struct vnc* v, const char *name);
-  int (*server_send_to_channel)(struct vnc* v, int channel_id,
-                                char* data, int data_len,
-                                int total_data_len, int flags);
-  int (*server_bell_trigger)(struct vnc* v);
-  tintptr server_dumby[100 - 25]; /* align, 100 minus the number of server
+    /* server functions */
+    int (*server_begin_update)(struct vnc *v);
+    int (*server_end_update)(struct vnc *v);
+    int (*server_fill_rect)(struct vnc *v, int x, int y, int cx, int cy);
+    int (*server_screen_blt)(struct vnc *v, int x, int y, int cx, int cy,
+                             int srcx, int srcy);
+    int (*server_paint_rect)(struct vnc *v, int x, int y, int cx, int cy,
+                             char *data, int width, int height, int srcx, int srcy);
+    int (*server_set_cursor)(struct vnc *v, int x, int y, char *data, char *mask);
+    int (*server_palette)(struct vnc *v, int *palette);
+    int (*server_msg)(struct vnc *v, const char *msg, int code);
+    int (*server_is_term)(struct vnc *v);
+    int (*server_set_clip)(struct vnc *v, int x, int y, int cx, int cy);
+    int (*server_reset_clip)(struct vnc *v);
+    int (*server_set_fgcolor)(struct vnc *v, int fgcolor);
+    int (*server_set_bgcolor)(struct vnc *v, int bgcolor);
+    int (*server_set_opcode)(struct vnc *v, int opcode);
+    int (*server_set_mixmode)(struct vnc *v, int mixmode);
+    int (*server_set_brush)(struct vnc *v, int x_origin, int y_origin,
+                            int style, char *pattern);
+    int (*server_set_pen)(struct vnc *v, int style,
+                          int width);
+    int (*server_draw_line)(struct vnc *v, int x1, int y1, int x2, int y2);
+    int (*server_add_char)(struct vnc *v, int font, int character,
+                           int offset, int baseline,
+                           int width, int height, char *data);
+    int (*server_draw_text)(struct vnc *v, int font,
+                            int flags, int mixmode, int clip_left, int clip_top,
+                            int clip_right, int clip_bottom,
+                            int box_left, int box_top,
+                            int box_right, int box_bottom,
+                            int x, int y, char *data, int data_len);
+    int (*server_reset)(struct vnc *v, int width, int height, int bpp);
+    int (*server_query_channel)(struct vnc *v, int index,
+                                char *channel_name,
+                                int *channel_flags);
+    int (*server_get_channel_id)(struct vnc *v, const char *name);
+    int (*server_send_to_channel)(struct vnc *v, int channel_id,
+                                  char *data, int data_len,
+                                  int total_data_len, int flags);
+    int (*server_bell_trigger)(struct vnc *v);
+    tintptr server_dumby[100 - 25]; /* align, 100 minus the number of server
                                      functions above */
-  /* common */
-  tintptr handle; /* pointer to self as long */
-  tintptr wm;
-  tintptr painter;
-  tintptr si;
-  /* mod data */
-  int server_width;
-  int server_height;
-  int server_bpp;
-  int mod_width;
-  int mod_height;
-  int mod_bpp;
-  char mod_name[256];
-  int mod_mouse_state;
-  int palette[256];
-  int vnc_desktop;
-  char username[256];
-  char password[256];
-  char ip[256];
-  char port[256];
-  int sck_closed;
-  int shift_state; /* 0 up, 1 down */
-  int keylayout;
-  int clip_chanid;
-  struct stream *clip_data_s;
-  int delay_ms;
-  struct trans *trans;
-  int got_guid;
-  tui8 guid[16];
-  int suppress_output;
+    /* common */
+    tintptr handle; /* pointer to self as long */
+    tintptr wm;
+    tintptr painter;
+    tintptr si;
+    /* mod data */
+    int server_width;
+    int server_height;
+    int server_bpp;
+    int mod_width;
+    int mod_height;
+    int mod_bpp;
+    char mod_name[256];
+    int mod_mouse_state;
+    int palette[256];
+    int vnc_desktop;
+    char username[256];
+    char password[256];
+    char ip[256];
+    char port[256];
+    int sck_closed;
+    int shift_state; /* 0 up, 1 down */
+    int keylayout;
+    int clip_chanid;
+    struct stream *clip_data_s;
+    int delay_ms;
+    struct trans *trans;
+    int got_guid;
+    tui8 guid[16];
+    int suppress_output;
+    /* Resizeable support */
+    int resizeable_mode;  /* true for resizeable mode, false for traditional */
+    struct vnc_screen_layout screen_layout;
+    int first_framebuffer_update; /* Identifies the first framebuffer_update */
+    int set_desktop_size_in_progress; /* Waiting for SetDesktopSize response */
 };

xrdp/xrdp.ini.in

@@ -171,6 +171,12 @@ ip=127.0.0.1
 port=-1
 #xserverbpp=24
 #delay_ms=2000
+; If your Xvnc server supports the ExtendedDesktopSize encoding, you can
+; uncomment the following line for resizeable session support. This includes
+; support for multiple monitors.
+; Unlike traditional VNC sessions, you can connect to (and resize) active
+; VNC sessions on the same machine which have different sizes.
+#code=1
 
 [vnc-any]
 name=vnc-any

xrdp/xrdp_mm.c

@@ -197,7 +197,7 @@ xrdp_mm_send_login(struct xrdp_mm *self)
         }
         else if (g_strcasecmp(name, "code") == 0)
         {
-            /* this code is either 0 for Xvnc, 10 for X11rdp or 20 for Xorg */
+            /* this code is either 0/1 for Xvnc, 10 for X11rdp or 20 for Xorg */
             self->code = g_atoi(value);
         }
         else if (g_strcasecmp(name, "xserverbpp") == 0)
@@ -215,7 +215,7 @@ xrdp_mm_send_login(struct xrdp_mm *self)
 
     s = trans_get_out_s(self->sesman_trans, 8192);
     s_push_layer(s, channel_hdr, 8);
-    /* this code is either 0 for Xvnc, 10 for X11rdp or 20 for Xorg */
+    /* this code is either 0/1 for Xvnc, 10 for X11rdp or 20 for Xorg */
     out_uint16_be(s, self->code);
     index = g_strlen(username);
     out_uint16_be(s, index);
@@ -515,7 +515,7 @@ xrdp_mm_setup_mod2(struct xrdp_mm *self, tui8 *guid)
     {
         if (self->display > 0)
         {
-            if (self->code == 0) /* Xvnc */
+            if (self->code == 0 || self->code == 1) /* Xvnc */
             {
                 g_snprintf(text, 255, "%d", 5900 + self->display);
             }
@@ -1903,7 +1903,7 @@ cleanup_states(struct xrdp_mm *self)
         self-> sesman_trans_up = 0; /* true once connected to sesman */
         self-> delete_sesman_trans = 0; /* boolean set when done with sesman connection */
         self-> display = 0; /* 10 for :10.0, 11 for :11.0, etc */
-        self-> code = 0; /* 0 Xvnc session, 10 X11rdp session, 20 Xorg session */
+        self-> code = 0; /* 0/1 Xvnc session, 10 X11rdp session, 20 Xorg session */
         self-> sesman_controlled = 0; /* true if this is a sesman session */
         self-> chan_trans = NULL; /* connection to chansrv */
         self-> chan_trans_up = 0; /* true once connected to chansrv */

xrdp/xrdp_types.h

@@ -290,7 +290,7 @@ struct xrdp_mm
   int (*mod_exit)(struct xrdp_mod*);
   struct xrdp_mod* mod; /* module interface */
   int display; /* 10 for :10.0, 11 for :11.0, etc */
-  int code; /* 0=Xvnc session, 10=X11rdp session, 20=xorg driver mode */
+  int code; /* 0/1=Xvnc session, 10=X11rdp session, 20=xorg driver mode */
   int sesman_controlled; /* true if this is a sesman session */
   struct trans* chan_trans; /* connection to chansrv */
   int chan_trans_up; /* true once connected to chansrv */