IFB
text/calendar
Magic Bytes
Offset: 0
42 45 47 49 4E 3A 56 43 41 4C 45 4E 44 41 52
The iCalendar Free/Busy (IFB) file is a text-based format derived from the iCalendar standard, originally defined by the Internet Engineering Task Force (IETF). This format is primarily employed by email and calendar applications, such as Microsoft Outlook and Apple Calendar, to transmit availability status without disclosing sensitive event details. While technically a plain text format containing no executable code, users should be aware that these files publicly broadcast schedule availability when published to shared servers.
Validation Code
How to validate .ifb files in Python
def is_ifb(file_path: str) -> bool:
"""Check if file is a valid IFB by magic bytes."""
signature = bytes([0x42, 0x45, 0x47, 0x49, 0x4E, 0x3A, 0x56, 0x43, 0x41, 0x4C, 0x45, 0x4E, 0x44, 0x41, 0x52])
with open(file_path, "rb") as f:
return f.read(15) == signatureHow to validate .ifb files in Node.js
function isIFB(buffer: Buffer): boolean {
const signature = Buffer.from([0x42, 0x45, 0x47, 0x49, 0x4E, 0x3A, 0x56, 0x43, 0x41, 0x4C, 0x45, 0x4E, 0x44, 0x41, 0x52]);
return buffer.subarray(0, 15).equals(signature);
}How to validate .ifb files in Go
func IsIFB(data []byte) bool {
signature := []byte{0x42, 0x45, 0x47, 0x49, 0x4E, 0x3A, 0x56, 0x43, 0x41, 0x4C, 0x45, 0x4E, 0x44, 0x41, 0x52}
if len(data) < 15 {
return false
}
return bytes.Equal(data[:15], signature)
}API Endpoint
/api/v1/ifb
curl https://filesignature.org/api/v1/ifb
Related Formats
Frequently Asked Questions
What is a .ifb file?
A .ifb file is a IFB file. The iCalendar Free/Busy (IFB) file is a text-based format derived from the iCalendar standard, originally defined by the Internet Engineering Task Force (IETF). This format is primarily employed by email and calendar applications, such as Microsoft Outlook and Apple Calendar, to transmit availability status without disclosing sensitive event details. While technically a plain text format containing no executable code, users should be aware that these files publicly broadcast schedule availability when published to shared servers.
What are the magic bytes for .ifb files?
The magic bytes for IFB files are 42 45 47 49 4E 3A 56 43 41 4C 45 4E 44 41 52 at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.
How do I validate a .ifb file?
To validate a .ifb file, read the first bytes of the file and compare them against the known magic bytes (42 45 47 49 4E 3A 56 43 41 4C 45 4E 44 41 52) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.
What is the MIME type for .ifb files?
The primary MIME type for .ifb files is text/calendar.
Is it safe to open .ifb files?
IFB (.ifb) files are generally safe to open. They are classified as low risk because they primarily contain data rather than executable code. However, always ensure files come from a trusted source.