feat: to network modifier

packages/adblocker/src/filters/network.ts

@@ -153,6 +153,7 @@ export const enum NETWORK_FILTER_MASK {
   isHostnameAnchor = 1 << 28,
   isRedirectRule = 1 << 29,
   isRedirect = 1 << 30,
+  isTo = 1 << 31,
   // IMPORTANT: the mask is now full, no more options can be added
   // Consider creating a separate fitler type for isReplace if a new
   // network filter option is needed.
@@ -731,8 +732,19 @@ export default class NetworkFilter implements IFilter {
         const value = rawOption[1];
 
         switch (option) {
+          case 'to':
           case 'denyallow': {
-            denyallow = Domains.parse(value.split('|'), debug);
+            if (denyallow !== undefined) {
+              return null;
+            }
+            let parts = value.split('|');
+            if (option === 'to') {
+              mask = setBit(mask, NETWORK_FILTER_MASK.isTo);
+              parts = parts.map((part) =>
+                part.charCodeAt(0) === 126 /* '~' */ ? part.slice(1) : `~${part}`,
+              );
+            }
+            denyallow = Domains.parse(parts, debug);
             break;
           }
           case 'domain':
@@ -1524,10 +1536,14 @@ export default class NetworkFilter implements IFilter {
     }
 
     if (this.denyallow !== undefined) {
+      const optionName = this.isTo() ? 'to' : 'denyallow';
       if (this.denyallow.parts !== undefined) {
-        options.push(`denyallow=${this.denyallow.parts}`);
+        const parts = this.denyallow.parts.split(',');
+        options.push(
+          `${optionName}=${this.isTo() ? parts.map((part) => (part.charCodeAt(0) === 126 /* '~' */ ? part.slice(1) : `~${part}`)).join('|') : parts.join('|')}`,
+        );
       } else {
-        options.push('denyallow=<hashed>');
+        options.push(`${optionName}=<hashed>`);
       }
     }
 
@@ -1818,6 +1834,10 @@ export default class NetworkFilter implements IFilter {
     return getBit(this.mask, NETWORK_FILTER_MASK.isBadFilter);
   }
 
+  public isTo() {
+    return getBit(this.mask, NETWORK_FILTER_MASK.isTo);
+  }
+
   public isUnicode() {
     return getBit(this.mask, NETWORK_FILTER_MASK.isUnicode);
   }

packages/adblocker/test/matching.test.ts

@@ -396,6 +396,23 @@ describe('#NetworkFilter.match', () => {
       url: 'https://sub.y.com/bar',
       type: 'script',
     });
+
+    // to
+    expect(f`*$3p,from=a.com,to=b.com`).to.matchRequest({
+      sourceUrl: 'https://a.com',
+      url: 'https://b.com/bar',
+      type: 'script',
+    });
+    expect(f`*$frame,3p,from=a.com|b.com,to=~c.com`).to.not.matchRequest({
+      sourceUrl: 'https://a.com',
+      url: 'https://c.com/bar',
+      type: 'sub_frame',
+    });
+    expect(f`$frame,csp=non-relevant,to=~safe.com,from=c.com|d.com`).to.not.matchRequest({
+      sourceUrl: 'https://c.com',
+      url: 'https://safe.com/foo',
+      type: 'sub_frame',
+    });
   });
 });
 

packages/adblocker/test/parsing.test.ts

@@ -803,6 +803,25 @@ describe('Network filters', () => {
           denyallow: undefined,
         });
       });
+
+      context('to', () => {
+        it('fails when both denyallow and to used', () => {
+          network('||foo.com$denyallow=foo.com,to=bar.com', null);
+          network('||foo.com$to=foo.com,denyallow=bar.com', null);
+        });
+
+        it('reverses domains condition', () => {
+          network('||foo.com$to=bar.com|baz.com', {
+            denyallow: {
+              hostnames: undefined,
+              entities: undefined,
+              notHostnames: h(['bar.com', 'baz.com']),
+              notEntities: undefined,
+              parts: undefined,
+            },
+          });
+        });
+      });
     });
 
     describe('redirect', () => {