gosaml
SAML client library written in Go (golang)
SAML is the successful OASIS standard for cloud based single sign on (SSO). SAML allows for companies that maintain a security infrastructure internally to allow using that same set of credentials via a safe, secure mechanism with externally hosted services.
For instance, New Relic allows you to configure a saml provider (https://newrelic.com/docs/subscriptions/saml-service-providers) so you can maintain your own credentials instead of using New Relic's.
Ping Identity has a nice video for SAML here: https://www.pingidentity.com/resource-center/Introduction-to-SAML-Video.cfm
Installation
Use the go get command to fetch gosaml and its dependencies into your local $GOPATH:
$ go get github.com/mattbaird/gosaml
Usage
Generating Unsigned AuthnRequests
package main
import (
"fmt"
"github.com/mattbaird/gosaml"
)
func main() {
// Configure the app and account settings
appSettings := saml.NewAppSettings("http://www.onelogin.net", "issuer")
accountSettings := saml.NewAccountSettings("cert", "http://www.onelogin.net")
// Construct an AuthnRequest
authRequest := saml.NewAuthorizationRequest(*appSettings, *accountSettings)
// Return a SAML AuthnRequest as a string
saml, err := authRequest.GetRequest(false)
if err != nil {
fmt.Println(err)
return
}
fmt.Println(saml)
}The above code will generate the following AuthnRequest XML:
<?xml version="1.0" encoding="UTF-8"?>
<samlp:AuthnRequest xmlns:samlp="urn:oasis:names:tc:SAML:2.0:protocol" xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion"
ID="_fd22bc94-0dee-489f-47d5-b86e3100268c" Version="2.0" ProtocolBinding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST"
AssertionConsumerServiceURL="http://www.onelogin.net" IssueInstant="2014-09-02T13:15:28" AssertionConsumerServiceIndex="0"
AttributeConsumingServiceIndex="0">
<saml:Issuer>https://sp.example.com/SAML2</saml:Issuer>
<samlp:NameIDPolicy AllowCreate="true" Format="urn:oasis:names:tc:SAML:2.0:nameid-format:transient"></samlp:NameIDPolicy>
<samlp:RequestedAuthnContext xmlns:samlp="urn:oasis:names:tc:SAML:2.0:protocol" Comparison="exact"></samlp:RequestedAuthnContext>
<saml:AuthnContextClassRef xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion">
urn:oasis:names:tc:SAML:2.0:ac:classes:PasswordProtectedTransport
</saml:AuthnContextClassRef>
</samlp:AuthnRequest>Generating Signed AuthnRequests
See the github wiki for basic instructions on generating an X.509 certificate for signing.
package main
import (
"fmt"
"github.com/mattbaird/gosaml"
)
func main() {
// Configure the app and account settings
appSettings := saml.NewAppSettings("http://www.onelogin.net", "issuer")
accountSettings := saml.NewAccountSettings("cert", "http://www.onelogin.net")
// Construct an AuthnRequest
authRequest := saml.NewAuthorizationRequest(*appSettings, *accountSettings)
// Return a SAML AuthnRequest as a string
saml, err := authRequest.GetSignedRequest(false, "/path/to/publickey.cer", "/path/to/privatekey.pem")
if err != nil {
fmt.Println(err)
return
}
fmt.Println(saml)
}The above code will generate the following AuthnRequest XML:
<?xml version="1.0" encoding="UTF-8"?>
<samlp:AuthnRequest xmlns:samlp="urn:oasis:names:tc:SAML:2.0:protocol" xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion"
xmlns:samlsig="http://www.w3.org/2000/09/xmldsig#" ID="_0a4ca0ba-a90c-4780-5f73-d0142f0f0c0f" Version="2.0"
ProtocolBinding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST" AssertionConsumerServiceURL="http://www.onelogin.net"
IssueInstant="2014-09-03T11:17:07" AssertionConsumerServiceIndex="0" AttributeConsumingServiceIndex="0">
<saml:Issuer>https://sp.example.com/SAML2</saml:Issuer>
<samlp:NameIDPolicy AllowCreate="true" Format="urn:oasis:names:tc:SAML:2.0:nameid-format:transient"/>
<samlp:RequestedAuthnContext xmlns:samlp="urn:oasis:names:tc:SAML:2.0:protocol" Comparison="exact"/>
<saml:AuthnContextClassRef xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion">
urn:oasis:names:tc:SAML:2.0:ac:classes:PasswordProtectedTransport
</saml:AuthnContextClassRef>
<samlsig:Signature Id="Signature1">
<samlsig:SignedInfo>
<samlsig:CanonicalizationMethod Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/>
<samlsig:SignatureMethod Algorithm="http://www.w3.org/2000/09/xmldsig#rsa-sha1"/>
<samlsig:Reference URI="#_0a4ca0ba-a90c-4780-5f73-d0142f0f0c0f">
<samlsig:Transforms>
<samlsig:Transform Algorithm="http://www.w3.org/2000/09/xmldsig#enveloped-signature"/>
</samlsig:Transforms>
<samlsig:DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1"/>
<samlsig:DigestValue>8nJJwstdugjt6LJ+pbICc2iBwCc=</samlsig:DigestValue>
</samlsig:Reference>
</samlsig:SignedInfo>
<samlsig:SignatureValue>J35w3/wk5pmrKn6qdfo4L0r0c...t2MGKH8w==</samlsig:SignatureValue>
<samlsig:KeyInfo>
<samlsig:X509Data>
<samlsig:X509Certificate>MIICKzCCAdWgAwIBA...JHpg+GVGdcCty+4xA==</samlsig:X509Certificate>
</samlsig:X509Data>
</samlsig:KeyInfo>
</samlsig:Signature>
</samlp:AuthnRequest>