Back to godoc.org
go.mozilla.org/pkcs7

Package pkcs7

v0.0.0 (432b235)
Latest Go to latest
Published: Jan 28, 2020 | License: MIT | Module: go.mozilla.org/pkcs7

Overview

Package pkcs7 implements parsing and generation of some PKCS#7 structures.

Index

Examples

Package Files

Constants

const (
	// EncryptionAlgorithmDESCBC is the DES CBC encryption algorithm
	EncryptionAlgorithmDESCBC = iota

	// EncryptionAlgorithmAES128CBC is the AES 128 bits with CBC encryption algorithm
	// Avoid this algorithm unless required for interoperability; use AES GCM instead.
	EncryptionAlgorithmAES128CBC

	// EncryptionAlgorithmAES256CBC is the AES 256 bits with CBC encryption algorithm
	// Avoid this algorithm unless required for interoperability; use AES GCM instead.
	EncryptionAlgorithmAES256CBC

	// EncryptionAlgorithmAES128GCM is the AES 128 bits with GCM encryption algorithm
	EncryptionAlgorithmAES128GCM

	// EncryptionAlgorithmAES256GCM is the AES 256 bits with GCM encryption algorithm
	EncryptionAlgorithmAES256GCM
)

Variables

var (
	// Signed Data OIDs
	OIDData                   = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 7, 1}
	OIDSignedData             = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 7, 2}
	OIDEnvelopedData          = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 7, 3}
	OIDEncryptedData          = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 7, 6}
	OIDAttributeContentType   = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 9, 3}
	OIDAttributeMessageDigest = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 9, 4}
	OIDAttributeSigningTime   = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 9, 5}

	// Digest Algorithms
	OIDDigestAlgorithmSHA1   = asn1.ObjectIdentifier{1, 3, 14, 3, 2, 26}
	OIDDigestAlgorithmSHA256 = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 1}
	OIDDigestAlgorithmSHA384 = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 2}
	OIDDigestAlgorithmSHA512 = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 3}

	OIDDigestAlgorithmDSA     = asn1.ObjectIdentifier{1, 2, 840, 10040, 4, 1}
	OIDDigestAlgorithmDSASHA1 = asn1.ObjectIdentifier{1, 2, 840, 10040, 4, 3}

	OIDDigestAlgorithmECDSASHA1   = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 1}
	OIDDigestAlgorithmECDSASHA256 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 2}
	OIDDigestAlgorithmECDSASHA384 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 3}
	OIDDigestAlgorithmECDSASHA512 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 4}

	// Signature Algorithms
	OIDEncryptionAlgorithmRSA       = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 1}
	OIDEncryptionAlgorithmRSASHA1   = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 5}
	OIDEncryptionAlgorithmRSASHA256 = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 11}
	OIDEncryptionAlgorithmRSASHA384 = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 12}
	OIDEncryptionAlgorithmRSASHA512 = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 13}

	OIDEncryptionAlgorithmECDSAP256 = asn1.ObjectIdentifier{1, 2, 840, 10045, 3, 1, 7}
	OIDEncryptionAlgorithmECDSAP384 = asn1.ObjectIdentifier{1, 3, 132, 0, 34}
	OIDEncryptionAlgorithmECDSAP521 = asn1.ObjectIdentifier{1, 3, 132, 0, 35}

	// Encryption Algorithms
	OIDEncryptionAlgorithmDESCBC     = asn1.ObjectIdentifier{1, 3, 14, 3, 2, 7}
	OIDEncryptionAlgorithmDESEDE3CBC = asn1.ObjectIdentifier{1, 2, 840, 113549, 3, 7}
	OIDEncryptionAlgorithmAES256CBC  = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 1, 42}
	OIDEncryptionAlgorithmAES128GCM  = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 1, 6}
	OIDEncryptionAlgorithmAES128CBC  = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 1, 2}
	OIDEncryptionAlgorithmAES256GCM  = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 1, 46}
)
var ContentEncryptionAlgorithm = EncryptionAlgorithmDESCBC

ContentEncryptionAlgorithm determines the algorithm used to encrypt the plaintext message. Change the value of this variable to change which algorithm is used in the Encrypt() function.

var ErrNotEncryptedContent = errors.New("pkcs7: content data is a decryptable data type")

ErrNotEncryptedContent is returned when attempting to Decrypt data that is not encrypted data

var ErrPSKNotProvided = errors.New("pkcs7: cannot encrypt content: PSK not provided")

ErrPSKNotProvided is returned when attempting to encrypt using a PSK without actually providing the PSK.

var ErrUnsupportedAlgorithm = errors.New("pkcs7: cannot decrypt data: only RSA, DES, DES-EDE3, AES-256-CBC and AES-128-GCM supported")

ErrUnsupportedAlgorithm tells you when our quick dev assumptions have failed

var ErrUnsupportedContentType = errors.New("pkcs7: cannot parse data: unimplemented content type")

ErrUnsupportedContentType is returned when a PKCS7 content is not supported. Currently only Data (1.2.840.113549.1.7.1), Signed Data (1.2.840.113549.1.7.2), and Enveloped Data are supported (1.2.840.113549.1.7.3)

var ErrUnsupportedEncryptionAlgorithm = errors.New("pkcs7: cannot encrypt content: only DES-CBC, AES-CBC, and AES-GCM supported")

ErrUnsupportedEncryptionAlgorithm is returned when attempting to encrypt content with an unsupported algorithm.

func DegenerateCertificate

func DegenerateCertificate(cert []byte) ([]byte, error)

DegenerateCertificate creates a signed data structure containing only the provided certificate or certificate chain.

func Encrypt

func Encrypt(content []byte, recipients []*x509.Certificate) ([]byte, error)

Encrypt creates and returns an envelope data PKCS7 structure with encrypted recipient keys for each recipient public key.

The algorithm used to perform encryption is determined by the current value of the global ContentEncryptionAlgorithm package variable. By default, the value is EncryptionAlgorithmDESCBC. To use a different algorithm, change the value before calling Encrypt(). For example:

ContentEncryptionAlgorithm = EncryptionAlgorithmAES128GCM

TODO(fullsailor): Add support for encrypting content with other algorithms

func EncryptUsingPSK

func EncryptUsingPSK(content []byte, key []byte) ([]byte, error)

EncryptUsingPSK creates and returns an encrypted data PKCS7 structure, encrypted using caller provided pre-shared secret.

type Attribute

type Attribute struct {
	Type  asn1.ObjectIdentifier
	Value interface{}
}

Attribute represents a key value pair attribute. Value must be marshalable byte `encoding/asn1`

type MessageDigestMismatchError

type MessageDigestMismatchError struct {
	ExpectedDigest []byte
	ActualDigest   []byte
}

MessageDigestMismatchError is returned when the signer data digest does not match the computed digest for the contained content

func (*MessageDigestMismatchError) Error

func (err *MessageDigestMismatchError) Error() string

type PKCS7

type PKCS7 struct {
	Content      []byte
	Certificates []*x509.Certificate
	CRLs         []pkix.CertificateList
	Signers      []signerInfo
	// contains filtered or unexported fields
}

PKCS7 Represents a PKCS7 structure

func Parse

func Parse(data []byte) (p7 *PKCS7, err error)

Parse decodes a DER encoded PKCS7 package

func (*PKCS7) Decrypt

func (p7 *PKCS7) Decrypt(cert *x509.Certificate, pkey crypto.PrivateKey) ([]byte, error)

Decrypt decrypts encrypted content info for recipient cert and private key

func (*PKCS7) DecryptUsingPSK

func (p7 *PKCS7) DecryptUsingPSK(key []byte) ([]byte, error)

DecryptUsingPSK decrypts encrypted data using caller provided pre-shared secret

func (*PKCS7) GetOnlySigner

func (p7 *PKCS7) GetOnlySigner() *x509.Certificate

GetOnlySigner returns an x509.Certificate for the first signer of the signed data payload. If there are more or less than one signer, nil is returned

func (*PKCS7) UnmarshalSignedAttribute

func (p7 *PKCS7) UnmarshalSignedAttribute(attributeType asn1.ObjectIdentifier, out interface{}) error

UnmarshalSignedAttribute decodes a single attribute from the signer info

func (*PKCS7) Verify

func (p7 *PKCS7) Verify() (err error)

Verify is a wrapper around VerifyWithChain() that initializes an empty trust store, effectively disabling certificate verification when validating a signature.

func (*PKCS7) VerifyWithChain

func (p7 *PKCS7) VerifyWithChain(truststore *x509.CertPool) (err error)

VerifyWithChain checks the signatures of a PKCS7 object. If truststore is not nil, it also verifies the chain of trust of the end-entity signer cert to one of the root in the truststore.

type SignedData

type SignedData struct {
	// contains filtered or unexported fields
}

SignedData is an opaque data structure for creating signed data payloads

Example

Code:

cert, err := createTestCertificate(x509.SHA256WithRSA)
if err != nil {
	fmt.Printf("Cannot create test certificates: %s", err)
}

signedData, err := NewSignedData([]byte("Example data to be signed"))
if err != nil {
	fmt.Printf("Cannot initialize signed data: %s", err)
}

if err := signedData.AddSigner(cert.Certificate, cert.PrivateKey, SignerInfoConfig{}); err != nil {
	fmt.Printf("Cannot add signer: %s", err)
}

signedData.Detach()

detachedSignature, err := signedData.Finish()
if err != nil {
	fmt.Printf("Cannot finish signing data: %s", err)
}
pem.Encode(os.Stdout, &pem.Block{Type: "PKCS7", Bytes: detachedSignature})

func NewSignedData

func NewSignedData(data []byte) (*SignedData, error)

NewSignedData takes data and initializes a PKCS7 SignedData struct that is ready to be signed via AddSigner. The digest algorithm is set to SHA1 by default and can be changed by calling SetDigestAlgorithm.

func (*SignedData) AddCertificate

func (sd *SignedData) AddCertificate(cert *x509.Certificate)

AddCertificate adds the certificate to the payload. Useful for parent certificates

func (*SignedData) AddSigner

func (sd *SignedData) AddSigner(ee *x509.Certificate, pkey crypto.PrivateKey, config SignerInfoConfig) error

AddSigner is a wrapper around AddSignerChain() that adds a signer without any parent.

func (*SignedData) AddSignerChain

func (sd *SignedData) AddSignerChain(ee *x509.Certificate, pkey crypto.PrivateKey, parents []*x509.Certificate, config SignerInfoConfig) error

AddSignerChain signs attributes about the content and adds certificates and signers infos to the Signed Data. The certificate and private key of the end-entity signer are used to issue the signature, and any parent of that end-entity that need to be added to the list of certifications can be specified in the parents slice.

The signature algorithm used to hash the data is the one of the end-entity certificate.

func (*SignedData) Detach

func (sd *SignedData) Detach()

Detach removes content from the signed data struct to make it a detached signature. This must be called right before Finish()

func (*SignedData) Finish

func (sd *SignedData) Finish() ([]byte, error)

Finish marshals the content and its signers

func (*SignedData) GetSignedData

func (sd *SignedData) GetSignedData() *signedData

GetSignedData returns the private Signed Data

func (*SignedData) RemoveAuthenticatedAttributes

func (sd *SignedData) RemoveAuthenticatedAttributes()

RemoveAuthenticatedAttributes removes authenticated attributes from signedData similar to OpenSSL's PKCS7_NOATTR or -noattr flags

func (*SignedData) RemoveUnauthenticatedAttributes

func (sd *SignedData) RemoveUnauthenticatedAttributes()

RemoveUnauthenticatedAttributes removes unauthenticated attributes from signedData

func (*SignedData) SetDigestAlgorithm

func (sd *SignedData) SetDigestAlgorithm(d asn1.ObjectIdentifier)

SetDigestAlgorithm sets the digest algorithm to be used in the signing process.

This should be called before adding signers

func (*SignedData) SetEncryptionAlgorithm

func (sd *SignedData) SetEncryptionAlgorithm(d asn1.ObjectIdentifier)

SetEncryptionAlgorithm sets the encryption algorithm to be used in the signing process.

This should be called before adding signers

func (*SignedData) SignWithoutAttr

func (sd *SignedData) SignWithoutAttr(ee *x509.Certificate, pkey crypto.PrivateKey, config SignerInfoConfig) error

SignWithoutAttr issues a signature on the content of the pkcs7 SignedData. Unlike AddSigner/AddSignerChain, it calculates the digest on the data alone and does not include any signed attributes like timestamp and so on.

This function is needed to sign old Android APKs, something you probably shouldn't do unless you're maintaining backward compatibility for old applications.

type SignerInfoConfig

type SignerInfoConfig struct {
	ExtraSignedAttributes   []Attribute
	ExtraUnsignedAttributes []Attribute
}

SignerInfoConfig are optional values to include when adding a signer

Documentation was rendered with GOOS=linux and GOARCH=amd64.

Jump to identifier

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to identifier