Use the hash command to calculate the MD5 or CRC-64 hash of a local file - Object Storage Service

Use the hash command to calculate the MD5 or CRC-64 hash of a local file.

Important

For ossutil 1.6.16 and later, you can use ossutil as the binary name in the command line regardless of your operating system. For versions earlier than 1.6.16, you must specify a binary name that corresponds to your operating system. For more information, see ossutil command reference.

Command syntax

ossutil hash localfile [--type=<value>]

The following table describes the parameters and options.

Parameter or option

Description

localfile

The full path of the local file.

--type

The type of data computation. The valid values are as follows:

md5: Calculates the MD5 hash of the local file.
If you set this parameter to md5, the command returns both the MD5 hash and the Content-MD5 value. The Content-MD5 value is the Base64-encoded 128-bit MD5 hash. For more information about Content-MD5, see RFC 1864.
crc64 (default): Calculates the CRC-64 hash of the local file. The calculation is based on CRC-64/XZ.

After you upload a file to a destination bucket, note the following about the file's CRC-64 and MD5 values:

You can run the stat command and check the X-Oss-Hash-Crc64ecma and Content-Md5 fields to obtain the CRC-64 and Content-MD5 values of the file. For more information, see stat (view bucket and object information).
You cannot run the stat command to view the CRC-64 value of a file that was uploaded to a bucket before OSS supported CRC-64 verification.
You cannot run the stat command to view the Content-MD5 value of a file that was uploaded using append upload or multipart upload.

Examples

Calculate the CRC-64 hash of the local file test.txt.

ossutil hash test.txt --type=crc64
CRC64-ECMA                  : 295992936743767023

Calculate the MD5 hash of the local file test.txt.

ossutil hash test.txt --type=md5
 MD5                         : 01C3C45C03B2AF225EFAD9F911A33D73
 Content-MD5                 : AcPEXAOyryJe+tn5EaM9cw==