Cleanup, refactoring, fix edge cases for directory jailing

example/child.js

+function (modules) {
+  if (typeof global === 'undefined') {
+    (function () {
+      var global = new Function('return this;')();
+      Object.defineProperty(global, 'global', {
+        value: global,
+        writable: true,
+        enumerable: false,
+        configurable: true
+      });
+    })();
+  }
+  // A stupid way to make dependencies available, that will
+  // probably necessary to be compatible with ye olde node.
+  global.dir = modules.dir
+  var testme = modules.compile('subexample/grandchild.js');
+  modules.print(JSON.stringify(testme(3, 4)));
+  return
+}

example/example.js

@@ -4,24 +4,9 @@ function (args) {
   var modules = args.modules;
   var Queues = args.Queues;
   var timers = Queues.timers;
-  if (typeof global === 'undefined') {
-    (function () {
-      var global = new Function('return this;')();
-      Object.defineProperty(global, 'global', {
-        value: global,
-        writable: true,
-        enumerable: false,
-        configurable: true
-      });
-    })();
-  }
-  var result = modules.dir('./src');
-  result.sort();
-  modules.print(JSON.stringify(result));
-  var testme = modules.assert_safe_path('testme.js');
-  var testme = modules.compile('testme.js');
+  var testme = modules.compile('child.js');
   testme(modules);
   // modules.print(Object.keys(args.modules));
   // modules.print(args.Queues.timers.length);
-  return result
+  return
 }

example/subexample/grandchild.js

+function (a, b) {
+  // var foo = dir('.');
+  var result = dir('docs');
+  result.push(a * b);
+  result.sort();
+  return result;
+}

example/subexample/testme.js

-function (a, b) {
-  return a * b;
-}

example/testme.js

-function (modules) {
-  var testme = modules.assert_safe_path('subexample/testme.js');
-  var testme = modules.compile('subexample/testme.js');
-  modules.print(testme(3, 4));
-  return
-}

src/app_assert_safe_path.c

@@ -6,11 +6,13 @@ duk_int_t app_assert_safe_path (duk_context *ctx) {
     return duk_error(ctx, DUK_ERR_ERROR, "Path cannot be empty.");
   } else if (filename[0] == '/') {
     return duk_error(ctx, DUK_ERR_ERROR, "Path should not start with '/' to reference the root directory: %s", filename);
+  } else if (strcmp(filename, "..") == 0) {
+    return duk_error(ctx, DUK_ERR_ERROR, "Path cannot be the parent directory '..'");
   } else if (strstr(filename, "../") != NULL) {
     return duk_error(ctx, DUK_ERR_ERROR, "Path should not contain '..' to reference parent directories: %s", filename);
-  } else if (filename[0] == '.') {
+  } else if (strncmp(filename, "./", 2) == 0) {
     // (this restriction isn't about safety, just consistancy and KISS)
-    return duk_error(ctx, DUK_ERR_ERROR, "Path should not start with '.' to reference the current directory: %s", filename);
+    return duk_error(ctx, DUK_ERR_ERROR, "Path should not start with extraneous './' reference the current directory: %s", filename);
   } else if (strstr(filename, "\\") != NULL) {
     // No paths with non-standard file separators.
     return duk_error(ctx, DUK_ERR_ERROR, "Path should not contain '\\' character, only use '/' to separate paths: %s", filename);

src/app_push_dir.c

 int app_push_dir (duk_context *ctx) {
-  // Check argument
-  const char *dirname = duk_require_string(ctx, -1);
-
+  // Safety check filename argument
+  app_assert_safe_path(ctx);
+  const char *dirname = duk_get_string(ctx, -1);
   // Construct array
   duk_idx_t dir_idx = duk_push_array(ctx);
-
   // Shove filenames into array
   struct dirent *dir;
   int i = 0;
+  int ii = 0;
   DIR *d = opendir(dirname);
   if (d) {
     while (i < 100) {
       dir = readdir(d);
       if (dir == NULL) break;
-      duk_push_string(ctx, dir->d_name);
-      duk_put_prop_index(ctx, dir_idx, i);
+      if (strcmp(dir->d_name, ".")  != 0 &&
+          strcmp(dir->d_name, "..") != 0) {
+        duk_push_string(ctx, dir->d_name);
+        duk_put_prop_index(ctx, dir_idx, ii);
+        ii++;
+      }
       i++;
     }
     closedir(d);

src/app_push_trusted_function.c

@@ -13,29 +13,20 @@ int app_push_trusted_function (duk_context *ctx) {
   // Replace with absolute filename
   duk_pop(ctx);
   duk_push_string(ctx, joined_path);
-  // Open the file
-  FILE * pFile = fopen(joined_path, "rb");
-  if (pFile == NULL) {
-    return duk_error(ctx, DUK_ERR_ERROR, "could not open file: %s", joined_path);
+  // Read the file
+  char *message = NULL;
+  char *buffer = NULL;
+  size_t bytesRead = NULL;
+  duk_int_t ret = c_read_script_file(joined_path, &message, &buffer, &bytesRead);
+  if (ret) {
+    if (buffer != NULL) free(buffer);
+    duk_push_error_object(ctx, DUK_ERR_ERROR, "%s", message);
+    free(message);
+    return duk_throw(ctx);
   }
-  // Get file size http://www.cplusplus.com/reference/cstdio/fread/
-  fseek(pFile, 0, SEEK_END);
-  long fileSize = ftell(pFile);
-  rewind(pFile);
-  // Allocate a buffer the write size
-  char * buffer = (char*) malloc (sizeof(char) * fileSize);
-  if (buffer == NULL) {
-    return duk_error(ctx, DUK_ERR_ERROR, "could not allocate memory: needed %d bytes to read %s", fileSize, joined_path);
-  }
-  // Dump file into memory
-  size_t bytesRead = fread(buffer, 1, fileSize, pFile);
-  if (bytesRead != fileSize) {
-    return duk_error(ctx, DUK_ERR_ERROR, "failed reading file: %s", joined_path);
-  }
-  // Close the file bc we're done with it
-  fclose(pFile);
   // Create a function from the file buffer. Leaves it on the stack.
   duk_compile_lstring_filename(ctx, DUK_COMPILE_FUNCTION + DUK_COMPILE_STRICT, buffer, bytesRead);
   free(buffer);
+  if (message != NULL) free(message);
   return 1;
 }

src/autogenerated.h

@@ -11,7 +11,8 @@ int app_push_trusted_function (duk_context *ctx);
 void app_stash_global_string(duk_context *ctx, char *name);
 void app_unstash_global_string(duk_context *ctx, char *name);
 char* c_join_paths(const char *base, const char *filename);
-int native_import (duk_context *ctx, char * filename);
+int c_read_script_file (const char *joined_path, char **message, char **buffer, size_t *bytesRead);
+int native_import (duk_context *ctx, const char *filename);
 static duk_ret_t native_print(duk_context *ctx);
 int queue_create(duk_context *ctx, char *name);
 int queue_push_queue(duk_context *ctx, char *name);
@@ -25,6 +26,7 @@ int queue_push_queue(duk_context *ctx, char *name);
 #include "app_stash_global_string.c"
 #include "app_unstash_global_string.c"
 #include "c_join_paths.c"
+#include "c_read_script_file.c"
 #include "native_import.c"
 #include "native_print.c"
 #include "queue/queue_create.c"

src/c_read_script_file.c

+int c_read_script_file (const char *joined_path, char **message, char **buffer, size_t *bytesRead) {
+  // Open the file
+  FILE * pFile = fopen(joined_path, "rb");
+  if (pFile == NULL) {
+    asprintf(message, "could not open file %s", joined_path);
+    return 1;
+  }
+  // Get file size http://www.cplusplus.com/reference/cstdio/fread/
+  fseek(pFile, 0, SEEK_END);
+  long int fileSize = ftell(pFile);
+  rewind(pFile);
+  // Allocate a buffer the write size
+  *buffer = (char*) malloc (sizeof(char) * fileSize);
+  if (*buffer == NULL) {
+    asprintf(message, "could not allocate the %ld bytes of memory to read %s", fileSize, joined_path);
+    return 2;
+  }
+  // Dump file into memory
+  *bytesRead = fread(*buffer, 1, fileSize, pFile);
+  if (*bytesRead != fileSize) {
+    asprintf(message, "failed reading file %s", joined_path);
+    return 3;
+  }
+  // Close the file bc we're done with it
+  fclose(pFile);
+  return 0;
+}

src/main.c

@@ -4,6 +4,7 @@
 extern char **environ;
 
 // Include dependencies
+#define _GNU_SOURCE
 #include <stdio.h>
 #include <stdlib.h>
 #include <dirent.h>
@@ -51,10 +52,6 @@ int main(int argc, char *argv[] /* char *environ[] */) {
     // Create a global (techinically heap-level) event queue
     queue_create(ctx, "timers");
 
-    // Creat a 2nd JS thread (yes, it's possible in Duktape!)
-    duk_push_thread(ctx); // TODO: Use duk_push_thread_new_globalenv for modules?
-    duk_context *ctx2 = duk_get_context(ctx, -1);
-
     // Load top-level function module
     duk_int_t ret = native_import(ctx, argv[1]);
     if (ret != 0) {
@@ -62,7 +59,7 @@ int main(int argc, char *argv[] /* char *environ[] */) {
       goto finally;
     }
 
-    // Construct the all-powerful god argument
+    // Construct the prime argument
     duk_push_object(ctx);
     // Create argv object
     app_push_argv(ctx, argc, argv);
@@ -89,7 +86,7 @@ int main(int argc, char *argv[] /* char *environ[] */) {
     duk_put_prop_string(ctx, -2, "timers");
     duk_put_prop_string(ctx, -2, "Queues");
 
-    // Run top-level module, passing the god arg as the sole argument.
+    // Run top-level module, passing the prime arg as the sole argument.
     ret = duk_pcall(ctx, 1);
     if (ret != 0) {
       fprintf(stderr, "%s %s\n", argv[1], duk_safe_to_string(ctx, -1));
@@ -99,61 +96,6 @@ int main(int argc, char *argv[] /* char *environ[] */) {
     //   duk_push_context_dump(ctx);
     //   printf("%s\n", duk_to_string(ctx, -1));
     // }
-
-    // Now trigger SOME of the event callbacks but not all
-    if (omp_get_thread_num() % 2) {
-      queue_push_queue(ctx, "timers");
-      duk_get_prop_index(ctx, -1, 0);
-      duk_remove(ctx, -2);
-      ret = duk_pcall(ctx, 0);
-      if (ret != 0) {
-        fprintf(stderr, "%s %s\n", argv[1], duk_safe_to_string(ctx, -1));
-        goto finally;
-      }
-    }
-
-
-    // Load top-level function module
-    ret = native_import(ctx2, argv[1]);
-    if (ret != 0) {
-      fprintf(stderr, "%s %s\n", argv[1], duk_safe_to_string(ctx2, -1));
-      goto finally;
-    }
-
-    // Construct the all-powerful god argument
-    duk_push_object(ctx2);
-    // Create argv object
-    app_push_argv(ctx2, argc, argv);
-    duk_put_prop_string(ctx2, -2, "argv");
-    // Create environment variables object
-    app_push_environ(ctx2);
-    duk_put_prop_string(ctx2, -2, "environ");
-    // Provide access to native functions
-    duk_push_object(ctx2);
-    duk_push_c_function(ctx2, app_push_dir, 1);
-    duk_put_prop_string(ctx2, -2, "dir");
-    duk_push_c_function(ctx2, native_print, DUK_VARARGS);
-    duk_put_prop_string(ctx2, -2, "print");
-    duk_get_global_string(ctx2, "Duktape");
-    duk_put_prop_string(ctx2, -2, "Duktape");
-    duk_put_prop_string(ctx2, -2, "modules");
-    // Provide direct access to the event loop
-    duk_push_object(ctx2);
-    queue_push_queue(ctx2, "timers");
-    duk_put_prop_string(ctx2, -2, "timers");
-    duk_put_prop_string(ctx2, -2, "Queues");
-
-    // Run top-level module, passing the god arg as the sole argument.
-    ret = duk_pcall(ctx2, 1);
-    if (ret != 0) {
-      fprintf(stderr, "%s %s\n", argv[1], duk_safe_to_string(ctx2, -1));
-      goto finally;
-    }
-    // else {
-    //   duk_push_context_dump(ctx);
-    //   printf("%s\n", duk_to_string(ctx, -1));
-    // }
-
   finally:
     duk_destroy_heap(ctx);
   #pragma omp critical

src/native_import.c

-int native_import (duk_context *ctx, char * filename) {
-  // Open the file
-  FILE * pFile = fopen(filename, "rb");
-  if (pFile == NULL) {
-    fputs("File error\n", stderr);
-    exit(1);
+int native_import (duk_context *ctx, const char *filename) {
+  char *message = NULL;
+  char *buffer = NULL;
+  size_t bytesRead = NULL;
+  duk_int_t ret = c_read_script_file(filename, &message, &buffer, &bytesRead);
+  if (ret) {
+    if (message != NULL) fprintf(stderr, "%s\n", message);
+    if (message != NULL) free(message);
+    if (buffer != NULL) free(buffer);
+    exit(ret);
   }
-  // Get file size http://www.cplusplus.com/reference/cstdio/fread/
-  fseek(pFile, 0, SEEK_END);
-  long fileSize = ftell(pFile);
-  rewind(pFile);
-  // Allocate a buffer the write size
-  char * buffer = (char*) malloc (sizeof(char) * fileSize);
-  if (buffer == NULL) {
-    fputs("Memory error\n", stderr);
-    exit(2);
-  }
-  // Dump file into memory
-  size_t bytesRead = fread(buffer, 1, fileSize, pFile);
-  if (bytesRead != fileSize) {
-    fputs("Reading error\n", stderr);
-    exit(3);
-  }
-  // Close the file bc we're done with it
-  fclose(pFile);
   // Create a function from the file buffer. Leaves it on the stack.
-  duk_int_t ret;
   duk_push_string(ctx, filename);
   ret = duk_pcompile_lstring_filename(ctx, DUK_COMPILE_FUNCTION + DUK_COMPILE_STRICT, buffer, bytesRead);
   free(buffer);
+  if (message != NULL) free(message);
   return ret;
 }

test.sh

@@ -2,13 +2,13 @@
 DUKBOOTS="${1:-./dukboots}"
 NUM_CORES="$(grep -c ^processor /proc/cpuinfo)"
 echo "$NUM_CORES cores"
-EXPECT_ONE='[".","..","app_push_argv.c","app_push_dir.c","app_push_environ.c","app_stash_global_string.c","app_unstash_global_string.c","main.c","native_import.c","native_print.c"]'
+EXPECT_ONE='[12,"index.html"]'
 EXPECT="$EXPECT_ONE"
-for n in $(seq 2 $((NUM_CORES * 2))); do
+for n in $(seq 2 $((NUM_CORES * 1))); do
   EXPECT="$EXPECT
 $EXPECT_ONE"
 done
-RESULT="$($DUKBOOTS example.js)"
+RESULT="$($DUKBOOTS example/example.js)"
 echo "$EXPECT"
 echo "---"
 echo "$RESULT"