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--- lib/viewcvs.py.orig Tue Jan 15 10:35:55 2002
+++ lib/viewcvs.py Fri Apr 25 19:18:22 2003
@@ -174,6 +174,10 @@
# parse the query params into a dictionary (and use defaults)
query_dict = default_settings.copy()
for name, values in cgi.parse().items():
+ # validate the parameter
+ _validate_param(name, values[0])
+
+ # if we're here, then the parameter is okay
query_dict[name] = values[0]
# set up query strings, prefixed by question marks and ampersands
@@ -228,6 +232,77 @@
self.branch = branch
self.taginfo = taginfo
+
+def _validate_param(name, value):
+ """Validate whether the given value is acceptable for the param name.
+
+ If the value is not allowed, then an error response is generated, and
+ this function throws an exception. Otherwise, it simply returns None.
+ """
+
+ try:
+ validator = _legal_params[name]
+ except KeyError:
+ error('An illegal parameter name ("%s") was passed.' % cgi.escape(name))
+
+ # is the validator a regex?
+ if hasattr(validator, 'match'):
+ if not validator.match(value):
+ error('An illegal value ("%s") was passed as a parameter.' %
+ cgi.escape(value))
+ return
+
+ # the validator must be a function
+ validator(value)
+
+def _validate_cvsroot(value):
+ if not cfg.general.cvs_roots.has_key(value):
+ error('The CVS root "%s" is unknown.' % cgi.escape(value))
+
+def _validate_regex(value):
+ # hmm. there isn't anything that we can do here.
+
+ ### we need to watch the flow of these parameters through the system
+ ### to ensure they don't hit the page unescaped. otherwise, these
+ ### parameters could constitute a CSS attack.
+ pass
+
+# obvious things here. note that we don't need uppercase for alpha.
+_re_validate_alpha = re.compile('^[a-z]+$')
+_re_validate_number = re.compile('^[0-9]+$')
+
+# when comparing two revs, we sometimes construct REV:SYMBOL, so ':' is needed
+_re_validate_revnum = re.compile('^[-_.a-zA-Z0-9:]+$')
+
+# it appears that RFC 2045 also says these chars are legal: !#$%&'*+^{|}~`
+# but woah... I'll just leave them out for now
+_re_validate_mimetype = re.compile('^[-_.a-zA-Z0-9/]+$')
+
+# the legal query parameters and their validation functions
+_legal_params = {
+ 'cvsroot' : _validate_cvsroot,
+ 'search' : _validate_regex,
+
+ 'hideattic' : _re_validate_number,
+ 'sortby' : _re_validate_alpha,
+ 'sortdir' : _re_validate_alpha,
+ 'logsort' : _re_validate_alpha,
+ 'diff_format' : _re_validate_alpha,
+ 'only_with_tag' : _re_validate_revnum,
+ 'dir_pagestart' : _re_validate_number,
+ 'log_pagestart' : _re_validate_number,
+ 'hidecvsroot' : _re_validate_number,
+ 'annotate' : _re_validate_revnum,
+ 'graph' : _re_validate_revnum,
+ 'makeimage' : _re_validate_number,
+ 'tarball' : _re_validate_number,
+ 'r1' : _re_validate_revnum,
+ 'tr1' : _re_validate_revnum,
+ 'r2' : _re_validate_revnum,
+ 'tr2' : _re_validate_revnum,
+ 'rev' : _re_validate_revnum,
+ 'content-type' : _re_validate_mimetype,
+ }
class LogEntry:
"Hold state for each revision entry in an 'rlog' output."
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