Adding upstream version 4.94.2.upstream/4.94.2upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 195 insertions, 0 deletions

diff --git a/src/lookups/dsearch.c b/src/lookups/dsearch.c
new file mode 100644
index 0000000..501293a
--- /dev/null
+++ b/src/lookups/dsearch.c
@@ -0,0 +1,195 @@
+/*************************************************
+*     Exim - an Internet mail transport agent    *
+*************************************************/
+
+/* Copyright (c) University of Cambridge 1995 - 2015 */
+/* Copyright (c) The Exim Maintainers 2020 */
+/* See the file NOTICE for conditions of use and distribution. */
+
+/* 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:
+lstat()) rather than a directory scan). */
+
+
+#include "../exim.h"
+#include "lf_functions.h"
+
+
+
+/*************************************************
+*              Open entry point                  *
+*************************************************/
+
+/* See local README for interface description. We open the directory to test
+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. */
+
+static void *
+dsearch_open(const uschar * dirname, uschar ** errmsg)
+{
+DIR * dp = exim_opendir(dirname);
+if (!dp)
+  {
+  int save_errno = errno;
+  *errmsg = string_open_failed(errno, "%s for directory search", dirname);
+  errno = save_errno;
+  return NULL;
+  }
+closedir(dp);
+return (void *)(-1);
+}
+
+
+/*************************************************
+*             Check entry point                  *
+*************************************************/
+
+/* The handle will always be (void *)(-1), but don't try casting it to an
+integer as this gives warnings on 64-bit systems. */
+
+static BOOL
+dsearch_check(void * handle, const uschar * filename, int modemask,
+  uid_t * owners, gid_t * owngroups, uschar ** errmsg)
+{
+handle = handle;
+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;
+}
+
+
+/*************************************************
+*              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. */
+
+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;
+unsigned flags = 0;
+
+handle = handle;  /* Keep picky compilers happy */
+length = length;
+do_cache = do_cache;
+
+if (Ustrchr(keystring, '/') != 0)
+  {
+  *errmsg = string_sprintf("key for dsearch lookup contains a slash: %s",
+    keystring);
+  return DEFER;
+  }
+
+if (opts)
+  {
+  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 ".." */
+      }
+  }
+
+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] != '.'
+   )  )  )  )
+  {
+  /* Since the filename exists in the filesystem, we can return a
+  non-tainted result. */
+  *result = string_copy_taint(flags & RET_FULL ? filename : keystring, FALSE);
+  return OK;
+  }
+
+if (errno == ENOENT || errno == 0) return FAIL;
+
+save_errno = errno;
+*errmsg = string_sprintf("%s: lstat: %s", filename, strerror(errno));
+errno = save_errno;
+return DEFER;
+}
+
+
+/*************************************************
+*              Close entry point                 *
+*************************************************/
+
+/* See local README for interface description */
+
+void
+static dsearch_close(void *handle)
+{
+handle = handle;   /* Avoid compiler warning */
+}
+
+
+/*************************************************
+*         Version reporting entry point          *
+*************************************************/
+
+/* See local README for interface description. */
+
+#include "../version.h"
+
+void
+dsearch_version_report(FILE *f)
+{
+#ifdef DYNLOOKUP
+fprintf(f, "Library version: dsearch: Exim version %s\n", EXIM_VERSION_STR);
+#endif
+}
+
+
+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 */