Kawayi kuke tuki upload fayiloli cikin tsafta?

Question

Accepted Answer

**Upload fayiloli** sune gama ya jisa sai cike haɗari mai mahimmanci — fayiloli marasa amfani zasu iya haifar da aiwatarwar lambar, yadasassun cuta, ko nakacewar tsarin. Tabbatarwa na upload ta buƙaci guba nau'in fayiloli, girman, da abun ciki, ajiyar fayiloli cikin tsafta, da kinajeye suki jiya.

## Haɗarin upload fayiloli

```text
Allowing users to upload files is dangerous if not secured:
  ✗ MALICIOUS executable/script files → could run on the server (e.g. uploading a web
    shell / script that gets executed → server compromise)
  ✗ MALWARE distribution (files served to other users)
  ✗ Oversized files → denial of service (disk/memory exhaustion)
  ✗ Path traversal in filenames (../../) → overwrite system files
  ✗ Files with misleading types/content (a .jpg that's actually a script)
```

## Tabbatarwa na upload fayiloli

```text
✓ VALIDATE file TYPE → check the actual CONTENT/MIME (not just the extension, which lies);
  ALLOWLIST permitted types (don't blocklist); reject everything else
✓ LIMIT file SIZE → prevent resource exhaustion (max upload size)
✓ Don't execute uploads → store OUTSIDE the web root; never serve from an executable
  directory; serve via a handler (not directly executable)
✓ RENAME files (random/generated names) → avoid path traversal and overwrites; sanitize
  filenames
✓ SCAN for malware where appropriate; set correct Content-Type/Content-Disposition when serving
✓ Use separate storage/domain or object storage (S3) for user files; access controls
```

## Me ya fa shi mahalacciya

Ganin yadda ake tabbatarwa na upload fayiloli a tsafta yana da mahimmanci saboda **upload fayiloli sune gama yadda ke da haɗari mai mahimmanci**, saboda haka jiya su a tsafta shi mahimmanci, wanda ya sa shi mahimmanci ilmin tsafta na aiki.

Ba da damar masu amfani na upload fayiloli yana buƙada haɗari mai yawa: **fayiloli marasa amfani na aiwatarwa/rubutu** waɗanda zasu iya gudana akan sarki (kamar tumashen yanar gida wanda ya haifar da cikakken tsabar sarki — haɗari mai tsanani), yadasassun cuta ga sauran masu amfani, rigingimin sabis daga fayiloli masu girma, **path traversal** a cikin sunan fayiloli (rubuta fayiloli na tsarin), da fayiloli masu nau'i mai ban ruɗi (.jpg wanda shine script kwatanci).

Wadannan suka sa upload fayiloli marasa tabbatarwa zama haɗari mai tsanani, gama yadda aka faɗa.

Ganin yadda ake **tabbatarwa upload** shi muhimmanci ilminta aiki: **guba nau'in fayiloli ta ainihin abun ciki/MIME** (ba kawai tsadar jiya, wanda zasu iya karya) da **bada izini** nau'in da aka yarda, **iyakance girman fayiloli** (tabbatar daga kashe albarkatu), mahimmanci **kara aiwatarwa upload** (ajiyar su waje daga tushen yanar gida kuma kada kinajeye daga jiya mai aiwatarwa — tabbatar daga haɗarin aiwatarwa lambar), **sake sunan fayiloli** da jiya sunan fayiloli (tabbatar daga path traversal da rubuta), nemo cuta a inda ya dace, saita nau'in abun ciki a daidai lokaci, da ajiyar abubuwa (kamar jiyya ajiyya) tare da iko sarrafa.

Wadannan abubuwan suka magance haɗarin kushe upload.

Saboda upload fayiloli sune gama yadda ke da haɗari mai mahimmanci, mai tsanani (keɓance tsabar sarki ta upload marasa amfani) da tabbatarwa su ta buƙaci abubuwan na musamman (nau'i/girman guba, ajiyar marasa aiwatarwa, sake sunan, kinajeye jiya), kuma ganin wadannan shi mahimmanci don kowane ajiyya tare da upload, ganin yadda ake tabbatarwa na upload fayiloli a tsafta shi mahimmanci, aiki-aiki ilminta tsafta — mahimmanci don gama yadda ke da haɗari, marasa tabbatarwa (aiwatarwa lambar, path traversal, DoS) tare da karfi na musamman, da ilminta mahimmanci domin kowane mai samar da upload aiki.