check_ref_format(): tighten refname rules

diff --git a/refs.c b/refs.c
index 8d3c502a151648abefc4afae70d1ec5f7b5d41b6..e355489e512e82df8e7ed22111157220eb01efc8 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -693,7 +693,7 @@ static inline int bad_ref_char(int ch)
 
 int check_ref_format(const char *ref)
 {
-       int ch, level, bad_type;
+       int ch, level, bad_type, last;
        int ret = CHECK_REF_FORMAT_OK;
        const char *cp = ref;
 
@@ -717,19 +717,24 @@ int check_ref_format(const char *ref)
                                return CHECK_REF_FORMAT_ERROR;
                }
 
+               last = ch;
                /* scan the rest of the path component */
                while ((ch = *cp++) != 0) {
                        bad_type = bad_ref_char(ch);
-                       if (bad_type) {
+                       if (bad_type)
                                return CHECK_REF_FORMAT_ERROR;
-                       }
                        if (ch == '/')
                                break;
-                       if (ch == '.' && *cp == '.')
+                       if (last == '.' && ch == '.')
+                               return CHECK_REF_FORMAT_ERROR;
+                       if (last == '@' && ch == '{')
                                return CHECK_REF_FORMAT_ERROR;
+                       last = ch;
                }
                level++;
                if (!ch) {
+                       if (ref <= cp - 2 && cp[-2] == '.')
+                               return CHECK_REF_FORMAT_ERROR;
                        if (level < 2)
                                return CHECK_REF_FORMAT_ONELEVEL;
                        return ret;