Update validation.py #83
Conversation
Added MIME-type validation
WalkthroughAdded MIME type validation to the Changes
Estimated code review effort🎯 2 (Simple) | ⏱️ ~10 minutes Poem
Pre-merge checks and finishing touches❌ Failed checks (1 warning, 1 inconclusive)
✅ Passed checks (1 passed)
✨ Finishing touches
🧪 Generate unit tests (beta)
Comment |
PR Compliance Guide 🔍Below is a summary of compliance checks for this PR:
Compliance status legend🟢 - Fully Compliant🟡 - Partial Compliant 🔴 - Not Compliant ⚪ - Requires Further Human Verification 🏷️ - Compliance label |
||||||||||||||||||
PR Code Suggestions ✨Explore these optional code suggestions:
|
||||||||||||
![coderabbitai[bot]](https://avatars.githubusercontent.com/in/347564?s=60&v=4){kind=small}
There was a problem hiding this comment.
Actionable comments posted: 1
🧹 Nitpick comments (2)
optifit backend/validation.py (2)
91-91: Minor: Follow PEP 8 comment style.Comments should have a space after
#and begin with a capital letter.Apply this diff:
- #mime type check + # MIME type check- #reset point for later processing + # Reset file pointer for later processingAlso applies to: 96-96
97-97: Redundant file pointer reset.The file pointer is already at position 0 from line 68, making this
seek(0)call redundant. However, this is defensive programming and doesn't cause issues.If you prefer to keep it for clarity (which is reasonable), consider adding a comment explaining why. Otherwise, you can remove it:
- #reset point for later processing - file.seek(0)
📜 Review details
Configuration used: CodeRabbit UI
Review profile: CHILL
Plan: Pro
📒 Files selected for processing (1)
optifit backend/validation.py(2 hunks)
🧰 Additional context used
🪛 Ruff (0.14.1)
optifit backend/validation.py
94-94: Avoid specifying long messages outside the exception class
(TRY003)
🔇 Additional comments (1)
optifit backend/validation.py (1)
3-3: Note:mimetypesis filename-based only, not content-based.The
mimetypesmodule determines MIME types by examining the filename extension, not the actual file content. This makes it unsuitable for security validation against malicious files.
| #mime type check | ||
| mime_type, _ = mimetypes.guess_type(file.filename) | ||
| if not mime_type or not mime_type.startswith('video/'): | ||
| raise UnsupportedMediaTypeError(f"Invalid MIME type: {mime_type}") |
There was a problem hiding this comment.
Critical: MIME validation is ineffective for security - validates filename only, not content.
mimetypes.guess_type() determines the MIME type based solely on the filename extension, not the actual file content. This means:
- A malicious executable renamed to
malware.mp4will pass this validation - This check duplicates the extension validation already performed on lines 85-90
- The PR description claims to prevent processing "dangerous or invalid files" based on their "actual nature," but this implementation does not achieve that goal
To properly validate file content, use a library that reads the file's magic bytes/signature:
Option 1 (Recommended): Use python-magic
Install the library:
pip install python-magicThen replace the MIME validation with content-based detection:
- #mime type check
- mime_type, _ = mimetypes.guess_type(file.filename)
- if not mime_type or not mime_type.startswith('video/'):
- raise UnsupportedMediaTypeError(f"Invalid MIME type: {mime_type}")
+ # MIME type check based on file content
+ import magic
+ file.seek(0)
+ file_header = file.read(2048)
+ file.seek(0)
+ mime_type = magic.from_buffer(file_header, mime=True)
+ if not mime_type or not mime_type.startswith('video/'):
+ raise UnsupportedMediaTypeError(f"Invalid MIME type: {mime_type}. File content does not match a video format.")Option 2: Use filetype library
Install the library:
pip install filetypeThen replace the MIME validation:
- #mime type check
- mime_type, _ = mimetypes.guess_type(file.filename)
- if not mime_type or not mime_type.startswith('video/'):
- raise UnsupportedMediaTypeError(f"Invalid MIME type: {mime_type}")
+ # MIME type check based on file content
+ import filetype
+ file.seek(0)
+ file_header = file.read(262)
+ file.seek(0)
+ kind = filetype.guess(file_header)
+ if not kind or not kind.mime.startswith('video/'):
+ raise UnsupportedMediaTypeError(f"Invalid file type. File content does not match a video format.")🧰 Tools
🪛 Ruff (0.14.1)
94-94: Avoid specifying long messages outside the exception class
(TRY003)
2 participants
User description
Added MIME-type validation
Description
Please explain the purpose of this PR and what it changes.
I have added MIME-type validation in the validation.py file so that we can get to know the actual nature of the file uploaded, making the system for safe and robust by preventing processing of dangerous and invalid files.
Related Issue
Link the issue this PR addresses (e.g., Closes #123).
Type of Change
How Has This Been Tested?
Explain the tests you ran and how reviewers can verify the changes.
I uploaded a file named video.exe by renaming it to video.mp4 and it was flagged invalid by mime.The reviewer can do the same.
Screenshots (if applicable)
Checklist
PR Type
Enhancement
Description
Add MIME-type validation to prevent file spoofing attacks
Validate uploaded video files against actual MIME types
Reset file pointer after validation for processing
Import
mimetypesmodule for MIME type detectionDiagram Walkthrough
flowchart LR A["File Upload"] --> B["Check Extension"] B --> C["Validate MIME Type"] C --> D{Valid Video?} D -->|Yes| E["Reset File Pointer"] E --> F["Return True"] D -->|No| G["Raise Error"]File Walkthrough
validation.py
Add MIME-type validation to video file validationoptifit backend/validation.py
mimetypesmodule for MIME type detectionvalidate_video_file()functionprocessing
UnsupportedMediaTypeErrorif MIME type is invalid or missingSummary by CodeRabbit