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gognupgkey-pair

gpg public key validation

I need to validate gpg public keys from users input but pem.Decode() does not work with the following public key unless I remove the checksum =dMc+ at the end. What is the right way to handle this? Thks

package main

import (
    "fmt"
    "encoding/pem"
)

func main() {
    pubkey :=`
-----BEGIN PGP PUBLIC KEY BLOCK-----
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=dMc+
-----END PGP PUBLIC KEY BLOCK-----`

    block, _ := pem.Decode([]byte(pubkey))

    if block != nil {
        fmt.Println("Decode worked : ", block.Type)
    }
}
Solution

  • You can use the golang.org/x/crypto/openpgp package:

    main.go

    package main

import (
        "bytes"
        "fmt"
        "os"
        "golang.org/x/crypto/openpgp"
)

func main() {
        r := bytes.NewReader([]byte(pubKey))
        keys, err := openpgp.ReadArmoredKeyRing(r)
        if err != nil {
                fmt.Printf("Unable to read armored key ring: %v\n", err)
                os.Exit(1)
        }
        for i, key := range keys {
                fmt.Printf("Key #%d identities:\n", i + 1)
                for name, _ := range key.Identities {
                        fmt.Printf("\t%s\n", name)
                }
        }
}

const pubKey = `
-----BEGIN PGP PUBLIC KEY BLOCK-----
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=dMc+
-----END PGP PUBLIC KEY BLOCK-----`

    Output

    $ go run main.go
Key #1 identities:
        testman <testman@testtest.com>