README
¶
Certificate Information for Go
A Golang tool for printing x509 TLS certificates in a format similar to OpenSSL.
This is a (maintained) fork of grantae/certinfo.
In addition to being able to extract and print standard information from any x509 certificate (request), it also includes capabilities to extract and print properties specific to the Smallstep toolchain and other, selected OIDs.
Installation
go get github.com/smallstep/certinfo
Usage
Print a certificate from a website
package main
import (
"crypto/tls"
"fmt"
"log"
"github.com/smallstep/certinfo"
)
func main() {
// Connect to google.com
cfg := tls.Config{}
conn, err := tls.Dial("tcp", "google.com:443", &cfg)
if err != nil {
log.Fatalln("TLS connection failed: " + err.Error())
}
// Grab the last certificate in the chain
certChain := conn.ConnectionState().PeerCertificates
cert := certChain[len(certChain)-1]
// Print the certificate
result, err := certinfo.CertificateText(cert)
if err != nil {
log.Fatal(err)
}
fmt.Print(result)
}
Print a PEM-encoded certificate from a file
package main
import (
"crypto/x509"
"encoding/pem"
"fmt"
"log"
"os"
"github.com/smallstep/certinfo"
)
func main() {
// Read and parse the PEM certificate file
pemData, err := os.ReadFile("cert.pem")
if err != nil {
log.Fatal(err)
}
block, rest := pem.Decode([]byte(pemData))
if block == nil || len(rest) > 0 {
log.Fatal("Certificate decoding error")
}
cert, err := x509.ParseCertificate(block.Bytes)
if err != nil {
log.Fatal(err)
}
// Print the certificate
result, err := certinfo.CertificateText(cert)
if err != nil {
log.Fatal(err)
}
fmt.Print(result)
}
Testing
go test github.com/smallstep/certinfo
This compares several PEM-encoded certificates with their expected outputs.
License
MIT -- see LICENSE for more information.
Documentation
¶
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func CertificateRequestShortText ¶
func CertificateRequestShortText(cr *x509.CertificateRequest) (string, error)
CertificateRequestShortText returns the human-readable string representation of the given certificate request using a short and friendly format.
func CertificateRequestText ¶
func CertificateRequestText(csr *x509.CertificateRequest) (string, error)
CertificateRequestText returns a human-readable string representation of the certificate request csr. The format is similar (but not identical) to the OpenSSL way of printing certificates.
func CertificateShortText ¶
func CertificateShortText(cert *x509.Certificate) (string, error)
CertificateShortText returns the human-readable string representation of the given cert using a short and friendly format.
func CertificateText ¶
func CertificateText(cert *x509.Certificate) (string, error)
CertificateText returns a human-readable string representation of the certificate cert. The format is similar (but not identical) to the OpenSSL way of printing certificates.
Types ¶
This section is empty.
Source Files