Add support for setting a custom CSP

app/config.py

@@ -109,6 +109,8 @@ class Config(pydantic.BaseModel):
 
     inbox_retention_days: int = 15
 
+    custom_content_security_policy: str | None = None
+
     # Config items to make tests easier
     sqlalchemy_database: str | None = None
     key_path: str | None = None
@@ -165,6 +167,7 @@ if CONFIG.privacy_replace:
 
 BLOCKED_SERVERS = {blocked_server.hostname for blocked_server in CONFIG.blocked_servers}
 ALSO_KNOWN_AS = CONFIG.also_known_as
+CUSTOM_CONTENT_SECURITY_POLICY = CONFIG.custom_content_security_policy
 
 INBOX_RETENTION_DAYS = CONFIG.inbox_retention_days
 CUSTOM_FOOTER = (

app/main.py

@@ -137,10 +137,16 @@ class CustomMiddleware:
                 headers["x-frame-options"] = "DENY"
                 headers["permissions-policy"] = "interest-cohort=()"
                 headers["content-security-policy"] = (
+                    (
                         f"default-src 'self'; "
                         f"style-src 'self' 'sha256-{HIGHLIGHT_CSS_HASH}'; "
                         f"frame-ancestors 'none'; base-uri 'self'; form-action 'self';"
                     )
+                    if not config.CUSTOM_CONTENT_SECURITY_POLICY
+                    else config.CUSTOM_CONTENT_SECURITY_POLICY.format(
+                        HIGHLIGHT_CSS_HASH=HIGHLIGHT_CSS_HASH
+                    )
+                )
                 if not DEBUG:
                     headers["strict-transport-security"] = "max-age=63072000;"
 

app/scss/main.scss

@@ -1,9 +1,11 @@
-$font-stack: Helvetica, sans-serif;
+$font-stack: -apple-system, BlinkMacSystemFont, avenir next, avenir, segoe ui, helvetica neue, helvetica, Cantarell,
+  Ubuntu, roboto, noto, arial, sans-serif;
+
 $background: #ddd;
 $light-background: #e6e6e6;
 $text-color: #111;
 $primary-color: #1d781d;
-$secondary-color: #781D78;
+$secondary-color: #781d78;
 $form-background-color: #ccc;
 $form-text-color: #333;
 $muted-color: #555; // solarized comment text
@@ -13,6 +15,46 @@ $code-highlight-background: #f0f0f0;
 // Load custom theme
 @import "theme.scss";
 
+/* Box sizing rules */
+*,
+*::before,
+*::after {
+  box-sizing: border-box;
+}
+
+/* Set core root defaults */
+html:focus-within {
+  scroll-behavior: smooth;
+}
+
+/* Inherit fonts for inputs and buttons */
+input,
+button,
+textarea,
+select {
+  font: inherit;
+}
+
+html {
+  max-width: 90ch;
+  padding: 3em 1em;
+  margin: auto;
+  line-height: 1.75;
+  font-size: 1.25em;
+}
+
+body {
+  font-family: $font-stack;
+  background: $background;
+  color: $text-color;
+  display: flex;
+  min-height: 100vh;
+  flex-direction: column;
+}
+a {
+  text-decoration: none;
+}
+
 .primary-color {
   color: $primary-color;
 }
@@ -84,7 +126,6 @@ $code-highlight-background: #f0f0f0;
   }
 }
 
-
 blockquote {
   border-left: 3px solid $secondary-color;
   margin-left: 0;
@@ -99,23 +140,6 @@ blockquote {
   background: $light-background;
 }
 
-
-body {
-  font-family: $font-stack;
-  font-size: 20px;
-  line-height: 32px;
-  background: $background;
-  color: $text-color;
-  margin: 0;
-  padding: 0;
-  display: flex;
-  min-height: 100vh;
-  flex-direction: column;
-}
-a {
-    text-decoration: none;
-}
-
 dl {
   display: flex;
   dt {
@@ -160,13 +184,16 @@ div.highlight {
   padding: 0 20px;
 }
 
-code, pre {
+code,
+pre {
   color: $secondary-color; // #cb4b16; // #268bd2; // #2aa198;
   font-family: monospace;
 }
 
 .form {
-    input, select, textarea {
+  input,
+  select,
+  textarea {
     font-size: 20px;
     border: 0;
     padding: 5px;
@@ -176,7 +203,7 @@ code, pre {
       outline: 1px solid $secondary-color;
     }
   }
-    input[type=submit] {
+  input[type="submit"] {
     font-size: 20px;
     outline: none;
     background: $primary-color;
@@ -217,7 +244,6 @@ a {
 }
 main {
   width: 100%;
-    max-width: 1000px;
   margin: 30px auto;
 }
 
@@ -237,8 +263,8 @@ main {
 }
 
 footer {
+  font-size: 1em;
   width: 100%;
-  max-width: 1000px;
   margin: 20px auto;
   color: $muted-color;
   p {
@@ -279,7 +305,9 @@ footer {
   }
 }
 
-#notifications, #followers, #following {
+#notifications,
+#followers,
+#following {
   ul {
     list-style-type: none;
     margin: 0;
@@ -304,7 +332,9 @@ footer {
   }
 }
 
-.show-sensitive-btn, .show-more-btn, .label-btn {
+.show-sensitive-btn,
+.show-more-btn,
+.label-btn {
   @include admin-button;
   padding: 10px 5px;
   margin: 20px 0;
@@ -335,13 +365,13 @@ ul.poll-items {
     }
 
     .poll-bar {
-       width:100%;height:20px;
+      width: 100%;
+      height: 20px;
       line {
         stroke: $secondary-color;
         stroke-width: 20px;
       }
     }
-
   }
 }
 
@@ -365,7 +395,8 @@ nav {
   form {
     margin: 15px 0;
   }
-    input[type=submit], button {
+  input[type="submit"],
+  button {
     @include admin-button;
   }
 }
@@ -378,7 +409,6 @@ nav.flexbox {
     list-style-type: none;
     margin: 0;
     padding: 0;
-
   }
 
   ul li {
@@ -391,7 +421,8 @@ nav.flexbox {
   a:not(.label-btn) {
     color: $primary-color;
     text-decoration: none;
-        &:hover, &:active {
+    &:hover,
+    &:active {
       color: $secondary-color;
       text-decoration: underline;
     }
@@ -421,14 +452,17 @@ a.label-btn {
     display: inline;
     color: $muted-color;
   }
-    .e-content, .activity-og-meta {
+  .e-content,
+  .activity-og-meta {
     a:hover {
       text-decoration: underline;
     }
   }
   .activity-attachment {
     margin: 30px 0 20px 0;
-        img, audio, video {
+    img,
+    audio,
+    video {
       width: 100%;
       max-width: 740px;
     }
@@ -471,7 +505,8 @@ a.label-btn {
 .actor-metadata {
   color: $muted-color;
 }
-.emoji, .custom-emoji {
+.emoji,
+.custom-emoji {
   max-width: 25px;
 }
 

app/templates.py

@@ -424,3 +424,4 @@ _templates.env.globals["BASE_URL"] = config.BASE_URL
 _templates.env.globals["HIDES_FOLLOWERS"] = config.HIDES_FOLLOWERS
 _templates.env.globals["HIDES_FOLLOWING"] = config.HIDES_FOLLOWING
 _templates.env.globals["NAVBAR_ITEMS"] = config.NavBarItems
+_templates.env.globals["ICON_URL"] = config.CONFIG.icon_url

app/templates/custom_page.html

@@ -14,7 +14,7 @@
 <meta content="{{ local_actor.display_name }}'s microblog" property="og:site_name" />
 <meta content="Homepage" property="og:title" />
 <meta content="{{ local_actor.summary | html2text | trim }}" property="og:description" />
-<meta content="{{ local_actor.url }}" property="og:image" />
+<meta content="{{ ICON_URL }}" property="og:image" />
 <meta content="summary" property="twitter:card" />
 <meta content="{{ local_actor.handle }}" property="profile:username" />
 {% endif %}

app/templates/header.html

@@ -26,11 +26,12 @@
 
 {%- macro header_link(url, text) -%}
 {% set url_for = BASE_URL + request.app.router.url_path_for(url) %}
-<a href="{{ url_for }}" {% if request.url.path == url_for %}class="active"{% endif %}>{{ text }}</a>
+<a href="{{ url_for }}" {% if BASE_URL + request.url.path == url_for %}class="active"{% endif %}>{{ text }}</a>
 {% endmacro %}
 
 {%- macro navbar_item_link(navbar_item) -%}
-<a href="{{ navbar_item[0] }}" {% if request.url.path == navbar_item[0] %}class="active"{% endif %}>{{ navbar_item[1] }}</a>
+{% set url_for = BASE_URL + navbar_item[0] %}
+<a href="{{ navbar_item[0] }}" {% if BASE_URL + request.url.path == url_for %}class="active"{% endif %}>{{ navbar_item[1] }}</a>
 {% endmacro %}
 
 <div class="public-top-menu">

app/templates/index.html

@@ -13,7 +13,7 @@
 <meta content="{{ local_actor.display_name }}'s microblog" property="og:site_name" />
 <meta content="Homepage" property="og:title" />
 <meta content="{{ local_actor.summary | html2text | trim }}" property="og:description" />
-<meta content="{{ local_actor.url }}" property="og:image" />
+<meta content="{{ ICON_URL }}" property="og:image" />
 <meta content="summary" property="twitter:card" />
 <meta content="{{ local_actor.handle }}" property="profile:username" />
 {% endblock %}

app/templates/layout.html

@@ -19,7 +19,7 @@
 <div id="admin">
 {% macro admin_link(url, text) %}
 {% set url_for = BASE_URL + request.app.router.url_path_for(url) %}
-<a href="{{ url_for }}" {% if request.url.path == url_for %}class="active"{% endif %}>{{ text }}</a>
+<a href="{{ url_for }}" {% if BASE_URL + request.url.path == url_for %}class="active"{% endif %}>{{ text }}</a>
 {% endmacro %}
 <div class="admin-menu">
 <nav class="flexbox">

docs/user_guide.md

@@ -131,9 +131,19 @@ See `app/scss/main.scss` to see what variables can be overridden.
 
 If you'd like to customize your instance's theme beyond CSS, you can modify the app's HTML by placing templates in `data/templates` which overwrite the defaults in `app/templates`.
 
+#### Custom Content Security Policy (CSP)
+
+You can override the default Content Security Policy by adding a line in `data/profile.toml`:
+
+```toml
+custom_content_security_policy = "default-src 'self'; style-src 'self' 'sha256-{HIGHLIGHT_CSS_HASH}'; frame-ancestors 'none'; base-uri 'self'; form-action 'self';"
+```
+
+This example will output the default CSP, note that `{HIGHLIGHT_CSS_HASH}` will be dynamically replaced by the correct value (the hash of the CSS needed for syntax highlighting).
+
 #### Code highlighting theme
 
-You can switch to one of the [styles supported by Pygments](https://pygments.org/styles/) by adding a line in `profile.toml`:
+You can switch to one of the [styles supported by Pygments](https://pygments.org/styles/) by adding a line in `data/profile.toml`:
 
 ```toml
 code_highlighting_theme = "solarized-dark"