X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/0f2cbd1b451dd142a372b6b0985c4ce2f37c04eb..a85c067ba6c6940512cf57ec213277a370d87e70:/src/src/lookups/dsearch.c

diff --git a/src/src/lookups/dsearch.c b/src/src/lookups/dsearch.c
index ecdf242a0..6cae0dafb 100644
--- a/src/src/lookups/dsearch.c
+++ b/src/src/lookups/dsearch.c
@@ -1,11 +1,11 @@
-/* $Cambridge: exim/src/src/lookups/dsearch.c,v 1.5 2007/05/31 12:42:07 magnus Exp $ */
-
 /*************************************************
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
-/* Copyright (c) University of Cambridge 1995 - 2007 */
+/* Copyright (c) The Exim Maintainers 2020 - 2022 */
+/* Copyright (c) University of Cambridge 1995 - 2015 */
 /* See the file NOTICE for conditions of use and distribution. */
+/* SPDX-License-Identifier: GPL-2.0-only */
 
 /* The idea for this code came from Matthew Byng-Maddick, but his original has
 been heavily reworked a lot for Exim 4 (and it now uses stat() (more precisely:
@@ -14,7 +14,6 @@ lstat()) rather than a directory scan). */
 
 #include "../exim.h"
 #include "lf_functions.h"
-#include "dsearch.h"
 
 
 
@@ -27,15 +26,13 @@ whether it exists and whether it is searchable. However, we don't need to keep
 it open, because the "search" can be done by a call to lstat() rather than
 actually scanning through the list of files. */
 
-void *
-dsearch_open(uschar *dirname, uschar **errmsg)
+static void *
+dsearch_open(const uschar * dirname, uschar ** errmsg)
 {
-DIR *dp = opendir(CS dirname);
-if (dp == NULL)
+DIR * dp = exim_opendir(dirname);
+if (!dp)
   {
-  int save_errno = errno;
-  *errmsg = string_open_failed(errno, "%s for directory search", dirname);
-  errno = save_errno;
+  *errmsg = string_open_failed("%s for directory search", dirname);
   return NULL;
   }
 closedir(dp);
@@ -50,13 +47,16 @@ return (void *)(-1);
 /* The handle will always be (void *)(-1), but don't try casting it to an
 integer as this gives warnings on 64-bit systems. */
 
-BOOL
-dsearch_check(void *handle, uschar *filename, int modemask, uid_t *owners,
-  gid_t *owngroups, uschar **errmsg)
+static BOOL
+dsearch_check(void * handle, const uschar * filename, int modemask,
+  uid_t * owners, gid_t * owngroups, uschar ** errmsg)
 {
 handle = handle;
-return lf_check_file(-1, filename, S_IFDIR, modemask, owners, owngroups,
-  "dsearch", errmsg) == 0;
+if (*filename == '/')
+  return lf_check_file(-1, filename, S_IFDIR, modemask, owners, owngroups,
+    "dsearch", errmsg) == 0;
+*errmsg = string_sprintf("dirname '%s' for dsearch is not absolute", filename);
+return FALSE;
 }
 
 
@@ -64,21 +64,26 @@ return lf_check_file(-1, filename, S_IFDIR, modemask, owners, owngroups,
 *              Find entry point                  *
 *************************************************/
 
+#define RET_FULL	BIT(0)
+#define FILTER_TYPE	BIT(1)
+#define FILTER_ALL	BIT(1)
+#define FILTER_FILE	BIT(2)
+#define FILTER_DIR	BIT(3)
+#define FILTER_SUBDIR	BIT(4)
+
 /* See local README for interface description. We use lstat() instead of
 scanning the directory, as it is hopefully faster to let the OS do the scanning
 for us. */
 
-int
-dsearch_find(void *handle, uschar *dirname, uschar *keystring, int length,
-  uschar **result, uschar **errmsg, BOOL *do_cache)
+static int
+dsearch_find(void * handle, const uschar * dirname, const uschar * keystring,
+  int length, uschar ** result, uschar ** errmsg, uint * do_cache,
+  const uschar * opts)
 {
 struct stat statbuf;
 int save_errno;
-uschar filename[PATH_MAX];
-
-handle = handle;  /* Keep picky compilers happy */
-length = length;
-do_cache = do_cache;
+uschar * filename;
+unsigned flags = 0;
 
 if (Ustrchr(keystring, '/') != 0)
   {
@@ -87,22 +92,47 @@ if (Ustrchr(keystring, '/') != 0)
   return DEFER;
   }
 
-if (!string_format(filename, sizeof(filename), "%s/%s", dirname, keystring))
+if (opts)
   {
-  *errmsg = US"path name too long";
-  return DEFER;
+  int sep = ',';
+  uschar * ele;
+
+  while ((ele = string_nextinlist(&opts, &sep, NULL, 0)))
+    if (Ustrcmp(ele, "ret=full") == 0)
+      flags |= RET_FULL;
+    else if (Ustrncmp(ele, "filter=", 7) == 0)
+      {
+      ele += 7;
+      if (Ustrcmp(ele, "file") == 0)
+	flags |= FILTER_TYPE | FILTER_FILE;
+      else if (Ustrcmp(ele, "dir") == 0)
+	flags |= FILTER_TYPE | FILTER_DIR;
+      else if (Ustrcmp(ele, "subdir") == 0)
+	flags |= FILTER_TYPE | FILTER_SUBDIR;	/* like dir but not "." or ".." */
+      }
   }
 
-if (Ulstat(filename, &statbuf) >= 0)
+filename = string_sprintf("%s/%s", dirname, keystring);
+if (  Ulstat(filename, &statbuf) >= 0
+   && (  !(flags & FILTER_TYPE)
+      || (flags & FILTER_FILE && S_ISREG(statbuf.st_mode))
+      || (  flags & (FILTER_DIR | FILTER_SUBDIR)
+       	 && S_ISDIR(statbuf.st_mode)
+	 && (  flags & FILTER_DIR
+	    || keystring[0] != '.'
+	    || keystring[1] && keystring[1] != '.'
+   )  )  )  )
   {
-  *result = string_copy(keystring);
+  /* Since the filename exists in the filesystem, we can return a
+  non-tainted result. */
+  *result = string_copy_taint(flags & RET_FULL ? filename : keystring, GET_UNTAINTED);
   return OK;
   }
 
-if (errno == ENOENT) return FAIL;
+if (errno == ENOENT || errno == 0) return FAIL;
 
 save_errno = errno;
-*errmsg = string_sprintf("%s: lstat failed", filename);
+*errmsg = string_sprintf("%s: lstat: %s", filename, strerror(errno));
 errno = save_errno;
 return DEFER;
 }
@@ -115,9 +145,47 @@ return DEFER;
 /* See local README for interface description */
 
 void
-dsearch_close(void *handle)
+static dsearch_close(void *handle)
 {
 handle = handle;   /* Avoid compiler warning */
 }
 
+
+/*************************************************
+*         Version reporting entry point          *
+*************************************************/
+
+/* See local README for interface description. */
+
+#include "../version.h"
+
+gstring *
+dsearch_version_report(gstring * g)
+{
+#ifdef DYNLOOKUP
+g = string_fmt_append(g, "Library version: dsearch: Exim version %s\n", EXIM_VERSION_STR);
+#endif
+return g;
+}
+
+
+static lookup_info _lookup_info = {
+  .name = US"dsearch",			/* lookup name */
+  .type = lookup_absfile,		/* uses absolute file name */
+  .open = dsearch_open,			/* open function */
+  .check = dsearch_check,		/* check function */
+  .find = dsearch_find,			/* find function */
+  .close = dsearch_close,		/* close function */
+  .tidy = NULL,				/* no tidy function */
+  .quote = NULL,			/* no quoting function */
+  .version_report = dsearch_version_report         /* version reporting */
+};
+
+#ifdef DYNLOOKUP
+#define dsearch_lookup_module_info _lookup_module_info
+#endif
+
+static lookup_info *_lookup_list[] = { &_lookup_info };
+lookup_module_info dsearch_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 1 };
+
 /* End of lookups/dsearch.c */