Fix problem solution access check; fixes DMOJ#1371

judge/models/comment.py

@@ -15,7 +15,7 @@
 
 from judge.models.contest import Contest
 from judge.models.interface import BlogPost
-from judge.models.problem import Problem
+from judge.models.problem import Problem, Solution
 from judge.models.profile import Profile
 from judge.utils.cachedict import CacheDict
 
@@ -62,10 +62,12 @@ def most_recent(cls, user, n, batch=None):
             .defer('author__about', 'body').order_by('-id')
 
         problem_cache = CacheDict(lambda code: Problem.objects.defer('description', 'summary').get(code=code))
+        solution_cache = CacheDict(lambda code: Solution.objects.defer('content').get(problem__code=code))
         contest_cache = CacheDict(lambda key: Contest.objects.defer('description').get(key=key))
         blog_cache = CacheDict(lambda id: BlogPost.objects.defer('summary', 'content').get(id=id))
 
         problem_access = CacheDict(lambda code: problem_cache[code].is_accessible_by(user))
+        solution_access = CacheDict(lambda code: problem_access[code] and solution_cache[code].is_accessible_by(user))
         contest_access = CacheDict(lambda key: contest_cache[key].is_accessible_by(user))
         blog_access = CacheDict(lambda id: blog_cache[id].can_see(user))
 
@@ -78,29 +80,26 @@ def most_recent(cls, user, n, batch=None):
                 break
             for comment in slice:
                 page_key = comment.page[2:]
-                if comment.page.startswith('p:') or comment.page.startswith('s:'):
-                    try:
-                        if problem_access[page_key]:
-                            comment.page_title = problem_cache[page_key].name
-                            output.append(comment)
-                    except Problem.DoesNotExist:
-                        pass
-                elif comment.page.startswith('c:'):
-                    try:
-                        if contest_access[page_key]:
-                            comment.page_title = contest_cache[page_key].name
-                            output.append(comment)
-                    except Contest.DoesNotExist:
-                        pass
-                elif comment.page.startswith('b:'):
-                    try:
-                        if blog_access[page_key]:
-                            comment.page_title = blog_cache[page_key].title
-                            output.append(comment)
-                    except BlogPost.DoesNotExist:
-                        pass
+                try:
+                    if comment.page.startswith('p:'):
+                        has_access = problem_access[page_key]
+                        comment.page_title = problem_cache[page_key].name
+                    elif comment.page.startswith('s:'):
+                        has_access = solution_access[page_key]
+                        comment.page_title = _('Editorial for %s') % problem_cache[page_key].name
+                    elif comment.page.startswith('c:'):
+                        has_access = contest_access[page_key]
+                        comment.page_title = contest_cache[page_key].name
+                    elif comment.page.startswith('b:'):
+                        has_access = blog_access[page_key]
+                        comment.page_title = blog_cache[page_key].title
+                    else:
+                        has_access = True
+                except ObjectDoesNotExist:
+                    pass
                 else:
-                    output.append(comment)
+                    if has_access:
+                        output.append(comment)
                 if len(output) >= n:
                     return output
         return output
@@ -149,8 +148,10 @@ def page_title(self):
         return self.get_page_title(self.page)
 
     def is_accessible_by(self, user):
-        if self.page.startswith('p:') or self.page.startswith('s:'):
+        if self.page.startswith('p:'):
             return Problem.objects.get(code=self.page[2:]).is_accessible_by(user)
+        elif self.page.startswith('s:'):
+            return Solution.objects.get(problem__code=self.page[2:]).is_accessible_by(user)
         elif self.page.startswith('c:'):
             return Contest.objects.get(key=self.page[2:]).is_accessible_by(user)
         elif self.page.startswith('b:'):

judge/models/problem.py

@@ -9,6 +9,7 @@
 from django.db.models.expressions import RawSQL
 from django.db.models.functions import Coalesce
 from django.urls import reverse
+from django.utils import timezone
 from django.utils.functional import cached_property
 from django.utils.translation import gettext_lazy as _
 
@@ -460,6 +461,15 @@ def get_absolute_url(self):
     def __str__(self):
         return _('Editorial for %s') % self.problem.name
 
+    def is_accessible_by(self, user):
+        if self.is_public and self.publish_on < timezone.now():
+            return True
+        if user.has_perm('judge.see_private_solution'):
+            return True
+        if self.problem.is_editable_by(user):
+            return True
+        return False
+
     class Meta:
         permissions = (
             ('see_private_solution', _('See hidden solutions')),

judge/views/problem.py

@@ -15,7 +15,7 @@
 from django.shortcuts import get_object_or_404
 from django.template.loader import get_template
 from django.urls import reverse
-from django.utils import timezone, translation
+from django.utils import translation
 from django.utils.functional import cached_property
 from django.utils.html import escape, format_html
 from django.utils.safestring import mark_safe
@@ -118,11 +118,9 @@ def get_context_data(self, **kwargs):
 
         solution = get_object_or_404(Solution, problem=self.object)
 
-        if (not solution.is_public or solution.publish_on > timezone.now()) and \
-                not self.request.user.has_perm('judge.see_private_solution') or \
-                (self.request.user.is_authenticated and
-                 self.request.profile.current_contest):
+        if not solution.is_accessible_by(self.request.user) or self.request.in_contest:
             raise Http404()
+
         context['solution'] = solution
         context['has_solved_problem'] = self.object.id in self.get_completed_problems()
         return context

templates/problem/problem.html

@@ -126,8 +126,7 @@ <h2 style="color:#393630; display: inline-block">{{ title }}</h2>
     {% endif %}
     <div><a href="{{ url('chronological_submissions', problem.code) }}">{{ _('All submissions') }}</a></div>
     <div><a href="{{ url('ranked_submissions', problem.code) }}">{{ _('Best submissions') }}</a></div>
-    {% if editorial and editorial.is_public and 
-            not (request.user.is_authenticated and request.profile.current_contest) %}
+    {% if (editorial and editorial.is_accessible_by(request.user)) and not request.in_contest %}
         <hr>
         <div><a href="{{ url('problem_editorial', problem.code) }}">{{ _('Read editorial') }}</a></div>
     {% endif %}