mod_dav: Refactor Lock-Token parsing into dav_parse_locktoken()

  helper in util.c, replacing duplicated inline parsing in
  mod_dav.c and ms_wdv.c.

* modules/dav/main/util.c (dav_parse_locktoken): New function.

* modules/dav/main/mod_dav.h (dav_parse_locktoken): Declare it.

* modules/dav/main/mod_dav.c (dav_method_unlock): Use
  dav_parse_locktoken() instead of inline bracket parsing.

* modules/dav/main/ms_wdv.c (dav_process_ms_wdv_lock): Likewise.
  (dav_process_ms_wdv_if_header): Add length check before indexing
  the If header value to avoid reading past an empty string.

Submitted by: metsw24-max <metsw24 gmail.com>
Github: closes #618

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1935940 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/modules/dav/main/mod_dav.c b/modules/dav/main/mod_dav.c
index 42b651f281963a52665a6a31ab4bafb4b352089f..2a024396f5f22ffad0683187629ac18ddff8d5a8 100644 (file)
--- a/modules/dav/main/mod_dav.c
+++ b/modules/dav/main/mod_dav.c
@@ -3606,18 +3606,9 @@ static int dav_method_unlock(request_rec *r)
         return HTTP_BAD_REQUEST;
     }
 
-    locktoken_txt = apr_pstrdup(r->pool, const_locktoken_txt);
-    if (locktoken_txt[0] != '<') {
-        /* ### should provide more specifics... */
-        return HTTP_BAD_REQUEST;
-    }
-    locktoken_txt++;
-
-    if (locktoken_txt[strlen(locktoken_txt) - 1] != '>') {
-        /* ### should provide more specifics... */
-        return HTTP_BAD_REQUEST;
-    }
-    locktoken_txt[strlen(locktoken_txt) - 1] = '\0';
+    err = dav_parse_locktoken(r->pool, const_locktoken_txt, &locktoken_txt);
+    if (err != NULL)
+        return dav_handle_err(r, err, NULL);
 
     if ((err = (*locks_hooks->parse_locktoken)(r->pool, locktoken_txt,
                                                &locktoken)) != NULL) {

diff --git a/modules/dav/main/mod_dav.h b/modules/dav/main/mod_dav.h
index a481c4dd28f42ec9aa4782e292cc101fd4f100ee..dd15c29ac83500716542830d93756458cf23e8ba 100644 (file)
--- a/modules/dav/main/mod_dav.h
+++ b/modules/dav/main/mod_dav.h
@@ -1331,6 +1331,9 @@ struct dav_hooks_propdb
 
 DAV_DECLARE(time_t) dav_get_timeout(request_rec *r);
 DAV_DECLARE(time_t) dav_get_timeout_string(request_rec *r, const char *s);
+DAV_DECLARE(dav_error *) dav_parse_locktoken(apr_pool_t *p,
+                                             const char *input,
+                                             char **output);
 
 /*
 ** Opaque, provider-specific information for a lock database.
@@ -2756,5 +2759,4 @@ DAV_DECLARE(const dav_resource_type_provider *) dav_get_resource_type_providers(
 #endif
 
 #endif /* _MOD_DAV_H_ */
-/** @} */
-
+/** @} */
\ No newline at end of file

diff --git a/modules/dav/main/ms_wdv.c b/modules/dav/main/ms_wdv.c
index cd9bb10cf532982665900c32fb7840671d0e25f8..1b80b9a8e2e90b231096a79925f9b88abe3d5e25 100644 (file)
--- a/modules/dav/main/ms_wdv.c
+++ b/modules/dav/main/ms_wdv.c
@@ -36,13 +36,16 @@ static void delete_if_fixup(request_rec *r)
     const char *if_hdr;
     const char *cp;
     apr_size_t len;
+    int has_open, has_close;
 
     if ((if_hdr =  apr_table_get(r->headers_in, "If")) == NULL)
         goto out;
 
     /* check for parenthesis enclosed value */
     len = strlen(if_hdr);
-    if (if_hdr[0] != '(' || if_hdr[len - 1]!= ')')
+    has_open = (len > 0 && if_hdr[0] == '(');
+    has_close = (len > 0 && if_hdr[len - 1] == ')');
+    if (!has_open || !has_close)
         goto out;
 
     for (cp = if_hdr; *cp; cp++) {
@@ -197,10 +200,13 @@ static dav_error *mswdv_combined_lock(request_rec *r)
      * section 4.5 suggests using Lock-Token without brakets.
      */
     if (lock_token_hdr) {
-        apr_size_t len = strlen(lock_token_hdr);
+        char *parsed_locktoken;
 
-        if (lock_token_hdr[0] == '<' || lock_token_hdr[len - 1] == '>')
-            lock_token_hdr = apr_pstrndup(r->pool, lock_token_hdr + 1, len - 2);
+        err = dav_parse_locktoken(r->pool, lock_token_hdr, &parsed_locktoken);
+        if (err != NULL)
+            goto out;
+
+        lock_token_hdr = parsed_locktoken;
     }
 
     if (lock_timeout_hdr) {
@@ -832,4 +838,3 @@ DAV_DECLARE(apr_status_t) dav_mswdv_input(ap_filter_t *f,
 
     return APR_SUCCESS;
 }
-

diff --git a/modules/dav/main/util.c b/modules/dav/main/util.c
index 87d110d1b2a6106d32c9e83d864c73eda13d0d53..df1b349b5ce524753c5d6757d0617380844d1872 100644 (file)
--- a/modules/dav/main/util.c
+++ b/modules/dav/main/util.c
@@ -590,6 +590,36 @@ DAV_DECLARE(time_t) dav_get_timeout_string(request_rec *r,
     return DAV_TIMEOUT_INFINITE;
 }
 
+DAV_DECLARE(dav_error *) dav_parse_locktoken(apr_pool_t *p,
+                                             const char *input,
+                                             char **output)
+{
+    char *token;
+    apr_size_t len;
+    int has_open;
+    int has_close;
+
+    *output = NULL;
+
+    len = strlen(input);
+    has_open = (len > 0 && input[0] == '<');
+    has_close = (len > 2 && input[len - 1] == '>');
+
+    if (len < 2 || !has_open || !has_close) {
+        return dav_new_error(p, HTTP_BAD_REQUEST, 0, 0,
+                             "Malformed Lock-Token");
+    }
+
+    token = apr_pstrmemdup(p, input + 1, len - 2);
+    if (*token == '\0') {
+        return dav_new_error(p, HTTP_BAD_REQUEST, 0, 0,
+                             "Malformed Lock-Token");
+    }
+
+    *output = token;
+    return NULL;
+}
+
 /* ---------------------------------------------------------------
 **
 ** If Header processing