feat: add ClamAV to scan for malicious files

backend/src/clamscan/clamscan.module.ts

@@ -0,0 +1,10 @@
+import { forwardRef, Module } from "@nestjs/common";
+import { FileModule } from "src/file/file.module";
+import { ClamScanService } from "./clamscan.service";
+
+@Module({
+  imports: [forwardRef(() => FileModule)],
+  providers: [ClamScanService],
+  exports: [ClamScanService],
+})
+export class ClamscanModule {}

backend/src/clamscan/clamscan.service.ts

@@ -0,0 +1,86 @@
+import { Injectable } from "@nestjs/common";
+import * as NodeClam from "clamscan";
+import * as fs from "fs";
+import { FileService } from "src/file/file.service";
+import { PrismaService } from "src/prisma/prisma.service";
+
+const clamscanConfig = {
+  clamdscan: {
+    host: process.env.NODE_ENV == "docker" ? "clamav" : "127.0.0.1",
+    port: 3310,
+    localFallback: false,
+  },
+  preference: "clamdscan",
+};
+
+@Injectable()
+export class ClamScanService {
+  constructor(
+    private fileService: FileService,
+    private prisma: PrismaService
+  ) {}
+
+  private ClamScan: Promise<NodeClam | null> = new NodeClam()
+    .init(clamscanConfig)
+    .then((res) => {
+      console.log("ClamAV is active");
+      return res;
+    })
+    .catch(() => {
+      console.log("ClamAV is not active");
+      return null;
+    });
+
+  async check(shareId: string) {
+    const clamScan = await this.ClamScan;
+
+    if (!clamScan) return [];
+
+    const infectedFiles = [];
+
+    const files = fs
+      .readdirSync(`./data/uploads/shares/${shareId}`)
+      .filter((file) => file != "archive.zip");
+
+    for (const fileId of files) {
+      const { isInfected } = await clamScan
+        .isInfected(`./data/uploads/shares/${shareId}/${fileId}`)
+        .catch(() => {
+          console.log("ClamAV is not active");
+          return { isInfected: false };
+        });
+
+      const fileName = (
+        await this.prisma.file.findUnique({ where: { id: fileId } })
+      ).name;
+
+      if (isInfected) {
+        infectedFiles.push({ id: fileId, name: fileName });
+      }
+    }
+
+    return infectedFiles;
+  }
+
+  async checkAndRemove(shareId: string) {
+    const infectedFiles = await this.check(shareId);
+
+    if (infectedFiles.length > 0) {
+      await this.fileService.deleteAllFiles(shareId);
+      await this.prisma.file.deleteMany({ where: { shareId } });
+
+      const fileNames = infectedFiles.map((file) => file.name).join(", ");
+
+      await this.prisma.share.update({
+        where: { id: shareId },
+        data: {
+          removedReason: `Your share got removed because the file(s) ${fileNames} are malicious.`,
+        },
+      });
+
+      console.log(
+        `Share ${shareId} deleted because it contained ${infectedFiles.length} malicious file(s)`
+      );
+    }
+  }
+}