Better error message during failed spawn of captive-sandbox-server(1).
[captive.git] / src / libcaptive / sandbox / split.c
index 3a42c02..10ce69f 100644 (file)
@@ -28,7 +28,6 @@
 #include "captive/rtl-file.h"
 #include <unistd.h>
 #include <fcntl.h>
-#include <linc/linc.h> /* for linc_main_get_loop() */
 #include "server-Directory.h"
 #include "server-Vfs.h"
 #include "../client/vfs.h"
 #include <errno.h>
 #include "../client/giochannel-blind.h"        /* for captive_giochannel_blind_new() */
 #include <signal.h>
+#include "../storage/relastblock.h"    /* for captive_storage_relastblock() */
+#include <sys/file.h>  /* flock() */
+
+#ifdef HAVE_ORBIT_LINK
+void link_set_tmpdir(const char *dir);
+#else
+#include <linc/linc.h> /* for linc_main_get_loop() */
+#endif
 
 
 /* CONFIG: */
@@ -82,7 +89,13 @@ gchar *orb_argv[]={
        CORBA_exception_init(evp);
 
        /* Init 'orb' */
-       *orbp=CORBA_ORB_init(&orb_argc,orb_argv,"orbit-local-orb",evp);
+       /* libcaptive is single-threaded only, caller must lock it.
+        * If thread A spawned the sandbox while currently doing its own work
+        * and thread B calls the sandbox thread B waits on ORB_run()
+        * while the sandbox waits for the response of thread A ORB. Deadlock.
+        * "orbit-local-non-threaded-orb" requests thread unaware ORB.
+        */
+       *orbp=CORBA_ORB_init(&orb_argc,orb_argv,"orbit-local-non-threaded-orb",evp);
        g_return_val_if_fail(*orbp!=CORBA_OBJECT_NIL,FALSE);
        g_return_val_if_fail(validate_CORBA_Environment(evp),FALSE);
 
@@ -168,13 +181,30 @@ void sandbox_child_prepare_shutdown(void)
 }
 #endif
 
+GMainLoop *captive_corba_get_loop(void)
+{
+#ifdef HAVE_ORBIT_LINK
+static GMainLoop *link_loop;
+
+       if (!link_loop)
+               link_loop=g_main_loop_new(g_main_context_default(),TRUE);
+       return link_loop;
+#else
+       return linc_main_get_loop();
+#endif
+}
+
+GMainContext *captive_corba_get_context(void)
+{
+       return g_main_loop_get_context(captive_corba_get_loop());
+}
 
 void sandbox_child_shutdown(void)
 {
        /* Do not fail by passing logging messages to the master. */
        impl_Captive_Vfs_init_g_log_func_disable();
 
-       g_main_loop_quit(linc_main_get_loop());
+       g_main_loop_quit(captive_corba_get_loop());
 }
 
 
@@ -243,10 +273,10 @@ int errint;
 
        heartbeat_source_callback_orb=captive_corba_orb;
 
-       /* linc_main_get_loop() makes sense only after corba_init() -> CORBA_ORB_init() */
+       /* captive_corba_get_context() makes sense only after corba_init() -> CORBA_ORB_init() */
        errguint=g_source_attach(
                        captive_corba_sandbox_child_heartbeat_gsource,  /* source */
-                       g_main_loop_get_context(linc_main_get_loop())); /* context; NULL means 'default context' */
+                       captive_corba_get_context());   /* context; NULL means 'default context' */
        g_assert(errguint!=0);
 
        /* Init 'Vfs_object' */
@@ -305,8 +335,12 @@ const gchar *socketname=NULL,*socketpathname;
        /* CORBA_ORB_run() -> linc_main_loop_run() -> g_main_loop_run()
         * and therefore we should be safe with glib events handling.
         */
+#ifdef HAVE_ORBIT_LINK
+       g_main_loop_run(captive_corba_get_loop());
+#else
        CORBA_ORB_run(captive_corba_orb,&captive_corba_ev);
        g_assert(validate_CORBA_Environment(&captive_corba_ev));
+#endif
 
        /* Shutdown 'Vfs' servant */
        Vfs_servant=PortableServer_POA_reference_to_servant(captive_corba_poa,Vfs_object,&captive_corba_ev);
@@ -331,11 +365,12 @@ static void options_module_captive_to_options_module_corba
 
        g_return_if_fail(src_options_module_captive->type==CAPTIVE_OPTIONS_MODULE_TYPE_PE32);
 
-       dest_options_module_corba->pathname_utf8=g_strdup(src_options_module_captive->pathname_utf8);
-       dest_options_module_corba->data._buffer=g_memdup(src_options_module_captive->u.pe32.base,
-                       src_options_module_captive->u.pe32.length);
+       dest_options_module_corba->pathname_utf8=CORBA_string_dup(src_options_module_captive->pathname_utf8);
        dest_options_module_corba->data._maximum=src_options_module_captive->u.pe32.length;
        dest_options_module_corba->data._length =src_options_module_captive->u.pe32.length;
+       dest_options_module_corba->data._buffer=Captive_Bytes_allocbuf(dest_options_module_corba->data._maximum);
+       memcpy(dest_options_module_corba->data._buffer,src_options_module_captive->u.pe32.base,
+                       src_options_module_captive->u.pe32.length);
        dest_options_module_corba->data._release=TRUE;
 }
 
@@ -435,6 +470,42 @@ struct sandbox_parent_own_orbit_dir_cleanup_signal *sigstructp;
                }
 }
 
+static void createlockdir(const gchar *dir)
+{
+gint retries;
+
+       for (retries=0;retries<10;retries++) {
+struct stat statbuf;
+int dirfd;
+
+               if (mkdir(dir,0700)) {
+                       if (errno!=EEXIST)
+                               g_error(_("Failed to create chroot directory \"%s\": %m"),dir);
+                       unlink_nonrecursive(dir);
+                       if (mkdir(dir,0700))
+                               g_error(_("Failed to create chroot directory \"%s\" after attempted unlink: %m"),dir);
+                       }
+               dirfd=open(dir,O_RDONLY);
+               if (dirfd==-1) {
+                       if (errno!=ENOENT)
+                               g_error(_("Failed to open created chroot directory \"%s\" to lock it: %m"),dir);
+                       continue;
+                       }
+               /* Do not use 'LOCK_NB' here as the garbage collector should release it soon. */
+               if (flock(dirfd,LOCK_EX))
+                       g_error(_("Failed to lock created chroot directory \"%s\": %m"),dir);
+               if (lstat(dir,&statbuf)) {
+                       if (errno!=ENOENT)
+                               g_error(_("Failed to lstat(2) created chroot directory \"%s\": %m"),dir);
+                       if (close(dirfd))
+                               g_error(_("Failed to close created and locked chroot directory \"%s\": %m"),dir);
+                       continue;
+                       }
+               /* Leave 'dirfd' open to leave it LOCK_EX-ed. */
+               break;
+               }
+}
+
 static gchar *sandbox_parent_read_ior
                (int Vfs_IOR_fd_read,gchar **child_chroot_pid_hashkey_dirp,CaptiveVfsParentObject *captive_vfs_parent_object)
 {
@@ -445,6 +516,7 @@ gchar *ior,*child_chroot_pid_hashkey_dir;
 int errint;
 gchar *s,*sd,*se;
 gboolean errbool;
+const gchar *ior_read_error;
 
        /* Initialize /tmp/orbit-$username directory for linking IOR socket. */
        errbool=corba_init("captive-sandbox-parent",&captive_corba_ev,&captive_corba_orb,&captive_corba_poa);
@@ -453,24 +525,34 @@ gboolean errbool;
        /* FIXME: Security: Duplicate giop_tmpdir_init() here. */
        if (!sandbox_parent_own_orbit_dir) {
                /* FIXME: Make 'CAPTIVE_SANDBOX_CHROOT' configurable. */
-               sandbox_parent_own_orbit_dir=g_strdup_printf("%s/tmp/captive-orbit-%d",CAPTIVE_SANDBOX_CHROOT,getpid());
-               if (mkdir(sandbox_parent_own_orbit_dir,0700)) {
-                       g_assert(errno==EEXIST);
-                       sandbox_parent_own_orbit_dir_cleanup_init();
-                       unlink_nonrecursive(sandbox_parent_own_orbit_dir);
-                       if (mkdir(sandbox_parent_own_orbit_dir,0700))
-                               g_assert_not_reached();
-                       }
+               /* Use also geteuid() marker here as could not remove the directory
+                * of some other user otherwise.
+                */
+               sandbox_parent_own_orbit_dir=g_strdup_printf("%s/tmp/captive-orbit-%d-%d",CAPTIVE_SANDBOX_CHROOT,getpid(),geteuid());
                sandbox_parent_own_orbit_dir_cleanup_init();
+               createlockdir(sandbox_parent_own_orbit_dir);
+#ifdef HAVE_ORBIT_LINK
+               link_set_tmpdir(sandbox_parent_own_orbit_dir);
+#else
                linc_set_tmpdir(sandbox_parent_own_orbit_dir);
+#endif
                }
 
        data=captive_rtl_file_read(Vfs_IOR_fd_read,&data_size); /* data_fd_read */
        errint=close(Vfs_IOR_fd_read);
-       g_assert(errint==0);
-       g_assert(data!=NULL);
-       g_assert(data_size>=1);
-       g_assert(data[data_size-1]=='\n');
+       ior_read_error=NULL;
+#define IOR_READ_ERROR(cond) G_STMT_START { \
+               if (!ior_read_error && !(cond)) \
+                       ior_read_error=G_STRINGIFY(cond); \
+               } G_STMT_END
+       IOR_READ_ERROR(errint==0);
+       IOR_READ_ERROR(data!=NULL);
+       IOR_READ_ERROR(data_size>=1);
+       IOR_READ_ERROR(data[data_size-1]=='\n');
+       if (ior_read_error)
+               g_error(_("Error connecting to the sandbox server (failed \"%s\"). Try running by hand: %s"),
+                               ior_read_error,CAPTIVE_VFS_OBJECT(captive_vfs_parent_object)->options.sandbox_server_argv[0]);
+#undef IOR_READ_ERROR
 
        hash=g_hash_table_new(g_str_hash,g_str_equal);
 
@@ -615,19 +697,32 @@ int errint;
        g_assert(validate_CORBA_Environment(&captive_corba_ev));
 
        /* Init 'CaptiveIOChannel_object' */
-       if (!captive_vfs_parent_object->corba_parent_giochanel_blind_source)
+       if (!captive_vfs_parent_object->corba_parent_giochanel_blind_source) {
+GIOChannel *giochannel;
+
+               giochannel=CAPTIVE_VFS_OBJECT(captive_vfs_parent_object)->options.image_iochannel;
+               g_io_channel_ref(giochannel);
+
+               giochannel=captive_storage_relastblock(giochannel);
+
                switch (CAPTIVE_VFS_OBJECT(captive_vfs_parent_object)->options.rwmode) {
                        case CAPTIVE_OPTION_RWMODE_RO:
                        case CAPTIVE_OPTION_RWMODE_RW:
-                               captive_vfs_parent_object->corba_parent_giochanel_blind_source=CAPTIVE_VFS_OBJECT(captive_vfs_parent_object)->options.image_iochannel;
                                break;
-                       case CAPTIVE_OPTION_RWMODE_BLIND:
-                               captive_vfs_parent_object->corba_parent_giochanel_blind_source=(GIOChannel *)captive_giochannel_blind_new(
-                                               CAPTIVE_VFS_OBJECT(captive_vfs_parent_object)->options.image_iochannel, /* giochannel_orig */
+                       case CAPTIVE_OPTION_RWMODE_BLIND: {
+GIOChannel *giochannel_orig;
+
+                               giochannel_orig=giochannel;
+                               giochannel=(GIOChannel *)captive_giochannel_blind_new(
+                                               giochannel,     /* giochannel_orig */
                                                TRUE); /* writeable */
-                               break;
+                               g_io_channel_unref(giochannel_orig);    /* reffed by captive_giochannel_blind_new() */
+                               } break;
                        default: g_assert_not_reached();
                        }
+               captive_vfs_parent_object->corba_parent_giochanel_blind_source=giochannel;
+               }
+
        if (!captive_vfs_parent_object->corba_parent_giochanel_blind)
                captive_vfs_parent_object->corba_parent_giochanel_blind=(GIOChannel *)captive_giochannel_blind_new(
                                captive_vfs_parent_object->corba_parent_giochanel_blind_source,  /* giochannel_orig */
@@ -699,7 +794,9 @@ gchar *s;
                g_assert(errint==0);
                }
 
-       options_corba.g_log_func=GLogFunc_object;
+       options_corba.g_log_func=CORBA_Object_duplicate(GLogFunc_object,&captive_corba_ev);
+       g_assert(validate_CORBA_Environment(&captive_corba_ev));
+
        options_module_captive_to_options_module_corba(&options_corba.filesystem,&CAPTIVE_VFS_OBJECT(captive_vfs_parent_object)->options.filesystem);
        /* Prevent secondary captive_giochannel_blind inside of our sandbox child
         * as we already have one captive_giochannel_blind in the parent.
@@ -708,12 +805,14 @@ gchar *s;
                        : CAPTIVE_VFS_OBJECT(captive_vfs_parent_object)->options.rwmode);
        options_corba.media         =CAPTIVE_VFS_OBJECT(captive_vfs_parent_object)->options.media;
        options_corba.debug_messages=CAPTIVE_VFS_OBJECT(captive_vfs_parent_object)->options.debug_messages;
-       options_corba.image_iochannel=CaptiveIOChannel_object;
+
+       options_corba.image_iochannel=CORBA_Object_duplicate(CaptiveIOChannel_object,&captive_corba_ev);
+       g_assert(validate_CORBA_Environment(&captive_corba_ev));
 
        load_module_length=g_list_length(CAPTIVE_VFS_OBJECT(captive_vfs_parent_object)->options.load_module);
-       captive_newn(options_corba.load_module._buffer,load_module_length);
        options_corba.load_module._maximum=load_module_length;
        options_corba.load_module._length=load_module_length;
+       options_corba.load_module._buffer=Captive_CaptiveOptionsModuleList_allocbuf(options_corba.load_module._maximum);
        options_corba.load_module._release=TRUE;
        for (load_moduleui=0,load_module_node=CAPTIVE_VFS_OBJECT(captive_vfs_parent_object)->options.load_module;
                        load_module_node;
@@ -725,7 +824,8 @@ gchar *s;
        Captive_Vfs_init(Vfs_object,&options_corba,&captive_corba_ev);
        g_assert(validate_CORBA_Environment(&captive_corba_ev));
 
-       /* FIXME: Free 'options_corba' - LEAK */
+       Captive_CaptiveOptions__freekids(&options_corba,
+                       NULL);  /* d; unused */
 
        captive_vfs_parent_object->corba_Vfs_object=Vfs_object;
        captive_vfs_parent_object->corba_GLogFunc_object=GLogFunc_object;
@@ -826,6 +926,8 @@ gboolean errbool;
                        g_return_val_if_reached(FALSE);
 
                case 0: { /* child */
+const char *sandbox_argv0;
+int execv_rc;
 
                        errint=close(Vfs_IOR_fds[0]);   /* close Vfs_IOR_fd_read */
                        g_return_val_if_fail(errint==0,FALSE);
@@ -841,8 +943,10 @@ gboolean errbool;
 
                        captive_sandbox_fd_closeup(2 /* STDERR */ +1);
 
-                       execv(CAPTIVE_VFS_OBJECT(captive_vfs_parent_object)->options.sandbox_server_argv[0],
+                       sandbox_argv0=CAPTIVE_VFS_OBJECT(captive_vfs_parent_object)->options.sandbox_server_argv[0];
+                       execv_rc=execv(sandbox_argv0,
                                        /* re-const */ (char * const *)CAPTIVE_VFS_OBJECT(captive_vfs_parent_object)->options.sandbox_server_argv);
+                       g_warning(_("Failed to spawn sandbox server - execv(\"%s\",...)=%d: %m"),sandbox_argv0,execv_rc);
                        g_return_val_if_reached(FALSE);
                        } /* NOTREACHED */