From eb10985372a6b6aa5c4e9efe97fbc7d38bfbc726 Mon Sep 17 00:00:00 2001
From: matt335672 <30179339+matt335672@users.noreply.github.com>
Date: Fri, 13 Sep 2024 12:08:31 +0100
Subject: [PATCH] Add support for creating sockdir to chansrv

Chansrv now checks for the user sockdir being present. If it
isn't, it connects to chansrv and requests it be created.

This also needs the sesman port to be added to the chansrv
config struct.

(cherry picked from commit c46eece00fc31b5eac2d1177a737518130fd3002)
---
 sesman/chansrv/Makefile.am      |  3 +-
 sesman/chansrv/chansrv.c        | 58 ++++++++++++++++++++++++++++
 sesman/chansrv/chansrv_config.c | 67 ++++++++++++++++++++++++++++++++-
 sesman/chansrv/chansrv_config.h |  3 ++
 4 files changed, 129 insertions(+), 2 deletions(-)

diff --git a/sesman/chansrv/Makefile.am b/sesman/chansrv/Makefile.am
index 959cdb52fb..8b7f9b363a 100644
--- a/sesman/chansrv/Makefile.am
+++ b/sesman/chansrv/Makefile.am
@@ -10,7 +10,8 @@ AM_CPPFLAGS = \
   -DXRDP_PID_PATH=\"${localstatedir}/run\" \
   -DXRDP_SOCKET_ROOT_PATH=\"${socketdir}\" \
   -I$(top_srcdir)/sesman/libsesman \
-  -I$(top_srcdir)/common
+  -I$(top_srcdir)/common \
+  -I$(top_srcdir)/libipm
 
 CHANSRV_EXTRA_LIBS =
 
diff --git a/sesman/chansrv/chansrv.c b/sesman/chansrv/chansrv.c
index 80f0a2314f..b3caf9fe55 100644
--- a/sesman/chansrv/chansrv.c
+++ b/sesman/chansrv/chansrv.c
@@ -41,6 +41,9 @@
 #include "xrdp_sockets.h"
 #include "audin.h"
 
+#include "scp.h"
+#include "scp_sync.h"
+
 #include "ms-rdpbcgr.h"
 
 #define MAX_PATH 260
@@ -1664,6 +1667,54 @@ run_exec(void)
     return 0;
 }
 
+/*****************************************************************************/
+/**
+ * Make sure XRDP_SOCKET_PATH exists
+ *
+ * We can't do anything without XRDP_SOCKET_PATH existing.
+ *
+ * Normally this is done by sesman before chansrv starts. If we're running
+ * standalone however (i.e. with x11vnc) this won't be done. We don't have the
+ * privilege to create the directory, so we have to ask sesman to do it
+ * for us.
+ */
+static int
+chansrv_create_xrdp_socket_path(void)
+{
+    char xrdp_socket_path[XRDP_SOCKETS_MAXPATH];
+    int rv = 1;
+
+    /* Use our UID to qualify XRDP_SOCKET_PATH */
+    g_snprintf(xrdp_socket_path, sizeof(xrdp_socket_path),
+               XRDP_SOCKET_PATH, g_getuid());
+
+    if (g_directory_exist(xrdp_socket_path))
+    {
+        rv = 0;
+    }
+    else
+    {
+        LOG(LOG_LEVEL_INFO, "%s doesn't exist - asking sesman to create it",
+            xrdp_socket_path);
+
+        struct trans *t = NULL;
+
+        if (!(t = scp_connect(g_cfg->listen_port, "xrdp-chansrv", g_is_term)))
+        {
+            LOG(LOG_LEVEL_ERROR, "Can't connect to sesman");
+        }
+        else if (scp_sync_uds_login_request(t) == 0 &&
+                 scp_sync_create_sockdir_request(t) == 0)
+        {
+            rv = 0;
+            (void)scp_send_close_connection_request(t);
+        }
+        trans_delete(t);
+    }
+
+    return rv;
+}
+
 /*****************************************************************************/
 int
 main(int argc, char **argv)
@@ -1756,6 +1807,13 @@ main(int argc, char **argv)
     }
 
     LOG_DEVEL(LOG_LEVEL_INFO, "main: app started pid %d(0x%8.8x)", pid, pid);
+
+    if (chansrv_create_xrdp_socket_path() != 0)
+    {
+        main_cleanup();
+        return 1;
+    }
+
     /*  set up signal handler  */
     g_signal_terminate(term_signal_handler); /* SIGTERM */
     g_signal_user_interrupt(term_signal_handler); /* SIGINT */
diff --git a/sesman/chansrv/chansrv_config.c b/sesman/chansrv/chansrv_config.c
index 000c8a4c8e..76b134a028 100644
--- a/sesman/chansrv/chansrv_config.c
+++ b/sesman/chansrv/chansrv_config.c
@@ -73,6 +73,61 @@ log_to_stdout(const enum logLevels lvl, const char *msg, ...)
     return LOG_STARTUP_OK;
 }
 
+/***************************************************************************//**
+ * Reads the config values we need from the [Globals] section
+ *
+ * @param logmsg Function to use to log messages
+ * @param names List of definitions in the section
+ * @params values List of corresponding values for the names
+ * @params cfg Pointer to structure we're filling in
+ *
+ * @return 0 for success
+ */
+static int
+read_config_globals(log_func_t logmsg,
+                    struct list *names, struct list *values,
+                    struct config_chansrv *cfg)
+{
+    int error = 0;
+    int index;
+
+    for (index = 0; index < names->count; ++index)
+    {
+        const char *name = (const char *)list_get_item(names, index);
+        const char *value = (const char *)list_get_item(values, index);
+
+        char unrecognised[256];
+        if (g_strcasecmp(name, "ListenPort") == 0)
+        {
+            char *listen_port = strdup(value);
+            if (listen_port == NULL)
+            {
+                LOG(LOG_LEVEL_WARNING,
+                    "Can't allocate config memory for ListenPort");
+            }
+            else
+            {
+                g_free(cfg->listen_port);
+                cfg->listen_port = listen_port;
+            }
+        }
+        if (g_strcasecmp(name, "RestrictInboundClipboard") == 0)
+        {
+            cfg->restrict_inbound_clipboard =
+                sesman_clip_restrict_string_to_bitmask(
+                    value, unrecognised, sizeof(unrecognised));
+            if (unrecognised[0] != '\0')
+            {
+                LOG(LOG_LEVEL_WARNING,
+                    "Unrecognised tokens parsing 'RestrictInboundClipboard' %s",
+                    unrecognised);
+            }
+        }
+    }
+
+    return error;
+}
+
 /***************************************************************************//**
  * Reads the config values we need from the [Security] section
  *
@@ -213,6 +268,7 @@ new_config(void)
     }
     else
     {
+        cfg->listen_port = NULL;
         cfg->enable_fuse_mount = DEFAULT_ENABLE_FUSE_MOUNT;
         cfg->restrict_outbound_clipboard = DEFAULT_RESTRICT_OUTBOUND_CLIPBOARD;
         cfg->restrict_inbound_clipboard = DEFAULT_RESTRICT_INBOUND_CLIPBOARD;
@@ -258,6 +314,11 @@ config_read(int use_logger, const char *sesman_ini)
             names->auto_free = 1;
             values->auto_free = 1;
 
+            if (!error && file_read_section(fd, "Globals", names, values) == 0)
+            {
+                error = read_config_globals(logmsg, names, values, cfg);
+            }
+
             if (!error && file_read_section(fd, "Security", names, values) == 0)
             {
                 error = read_config_security(logmsg, names, values, cfg);
@@ -288,9 +349,12 @@ config_read(int use_logger, const char *sesman_ini)
 void
 config_dump(struct config_chansrv *config)
 {
+    char buf[256];
+
     g_writeln("Global configuration:");
+    g_writeln("    xrdp-sesman ListenPort:    %s",
+              (config->listen_port) ? config->listen_port : "<default>");
 
-    char buf[256];
     g_writeln("\nSecurity configuration:");
     sesman_clip_restrict_mask_to_string(
         config->restrict_outbound_clipboard,
@@ -319,6 +383,7 @@ config_free(struct config_chansrv *cc)
 {
     if (cc != NULL)
     {
+        g_free(cc->listen_port);
         g_free(cc->fuse_mount_name);
         g_free(cc);
     }
diff --git a/sesman/chansrv/chansrv_config.h b/sesman/chansrv/chansrv_config.h
index a7b30bc694..b438a302be 100644
--- a/sesman/chansrv/chansrv_config.h
+++ b/sesman/chansrv/chansrv_config.h
@@ -23,6 +23,9 @@
 
 struct config_chansrv
 {
+    /** sesman listening port */
+    char *listen_port;
+
     /** Whether the FUSE mount is enabled or not */
     int enable_fuse_mount;