Signing and Verifying

In addition to creating accounts, leo account can be used to sign data and verify signatures. This can be useful for a particular class of applications that rely on signed data as input.

Signing

The leo account sign command enables developers and users to create cryptographic signatures using an Aleo private key. These signatures can be verified within leo using the signature::verify function or with the leo account verify command.

To generate a signature for Leo and Aleo values, run the following:

# replace `5field` with any aleo value
leo account sign --private-key {$PRIVATE_KEY} -m 5field

# Output:
sign1...

To generate a signature for any plaintext, use the --raw flag:

# replace "Hello, Aleo" with any plaintext message
leo account sign --private-key {$PRIVATE_KEY} -raw -m "Hello, Aleo"

# Output:
sign1...

There are a few alternatives to using the --private-key flag:

• --private-key-file <path/to/file> - read a private key from a text file
• no flags - read a private key from environment, or .env

Verifying

To complement with the leo account sign command, the leo account verify command verifies the signatures of Aleo values and plaintext messages.

To verify signed aleo values, run:

# replace `5field` with the message and `sign1signaturehere` with the signature
leo account verify -a {$ADDRESS} -m 5field -s sign1signaturehere

# Output:
✅ The signature is valid

# Error Output:
Error [ECLI0377002]: cli error: ❌ The signature is invalid

To verify signatures of signed plaintext values, run:

# replace "Hello, Aleo" with the message and `sign1signaturehere` with the signature
leo account verify -a {$ADDRESS} --raw -m "Hello, Aleo" -s sign1signaturehere

# Output:
✅ The signature is valid

# Error Output:
Error [ECLI0377002]: cli error: ❌ The signature is invalid