feat: add certificate service and utility functions

- Implement CertificateService for end-to-end certificate management
- Add support for various certificate types (web, client, email, etc.)
- Include certificate generation, validation, and revocation
- Add utility functions for certificate operations and validation
- Implement comprehensive test coverage for certificate operations
- Support SAN (Subject Alternative Name) and IP address extensions
- Add proper error handling and validation for certificate requests
This commit is contained in:
Björn Benouarets
2025-09-30 11:45:05 +02:00
parent 5f6640d8f3
commit d9726d9204
4 changed files with 2558 additions and 0 deletions

View File

@@ -0,0 +1,783 @@
package utils
import (
"crypto/ecdsa"
"crypto/elliptic"
"crypto/rand"
"crypto/rsa"
"crypto/sha256"
"crypto/x509"
"crypto/x509/pkix"
"encoding/asn1"
"encoding/pem"
"fmt"
"math/big"
"net"
"net/url"
"strings"
"time"
"git.secnex.io/secnex/certman/models"
)
// KeyType represents the type of cryptographic key
type KeyType string
const (
KeyTypeRSA KeyType = "rsa"
KeyTypeECDSA KeyType = "ecdsa"
)
// KeySize represents the size of RSA keys
type KeySize int
const (
KeySize2048 KeySize = 2048
KeySize3072 KeySize = 3072
KeySize4096 KeySize = 4096
)
// Curve represents ECDSA curves
type Curve string
const (
CurveP256 Curve = "P-256"
CurveP384 Curve = "P-384"
CurveP521 Curve = "P-521"
)
// CertificateConfig holds configuration for certificate generation
type CertificateConfig struct {
// Basic Information
CommonName string
Organization string
OrganizationalUnit string
Country string
State string
Locality string
Street string
PostalCode string
Email string
// Certificate Details
SerialNumber *big.Int
NotBefore time.Time
NotAfter time.Time
CertificateType models.CertificateType
// Subject Alternative Names
DNSNames []string
IPAddresses []net.IP
EmailAddresses []string
URIs []string
// Key Configuration
KeyType KeyType
KeySize KeySize // Only used for RSA
Curve Curve // Only used for ECDSA
// CA Configuration
IsCA bool
MaxPathLen int
MaxPathLenZero bool
BasicConstraintsValid bool
// Key Usage
DigitalSignature bool
ContentCommitment bool
KeyEncipherment bool
DataEncipherment bool
KeyAgreement bool
KeyCertSign bool
CRLSign bool
EncipherOnly bool
DecipherOnly bool
// Extended Key Usage
ServerAuth bool
ClientAuth bool
CodeSigning bool
EmailProtection bool
TimeStamping bool
OCSPSigning bool
// Additional Extensions
SubjectKeyID bool
AuthorityKeyID bool
CRLDistributionPoints []string
OCSPServers []string
// iOS-specific extensions
AuthorityInfoAccess []string // AIA URLs for iOS compatibility
IssuingCertificateURL string // URL to issuing certificate
// Validity period configuration
ValidityYears int // Custom validity period in years (overrides default)
// Platform compatibility
UseSHA256ForKeyIDs bool // Use SHA-256 for Key IDs (iOS compatible, MacBook compatible)
}
// DefaultCertificateConfig returns a default configuration for the given certificate type
func DefaultCertificateConfig(certType models.CertificateType) *CertificateConfig {
config := &CertificateConfig{
CommonName: "",
Organization: "",
OrganizationalUnit: "",
Country: "DE",
State: "",
Locality: "",
Street: "",
PostalCode: "",
Email: "",
SerialNumber: generateSerialNumber(),
NotBefore: time.Now(),
NotAfter: time.Now().AddDate(0, 3, 0), // 3 months default
CertificateType: certType,
DNSNames: []string{},
IPAddresses: []net.IP{},
EmailAddresses: []string{},
URIs: []string{},
KeyType: KeyTypeRSA,
KeySize: KeySize2048,
Curve: CurveP256,
IsCA: false,
MaxPathLen: -1,
MaxPathLenZero: false,
BasicConstraintsValid: true,
SubjectKeyID: true,
AuthorityKeyID: true,
CRLDistributionPoints: []string{},
OCSPServers: []string{},
// iOS-specific defaults
AuthorityInfoAccess: []string{},
IssuingCertificateURL: "",
// Validity period defaults
ValidityYears: 0, // 0 means use default
// Platform compatibility defaults
UseSHA256ForKeyIDs: true, // Use SHA-256 for modern compatibility (iOS + MacBook)
}
// Set defaults based on certificate type
switch certType {
case models.CertificateTypeCA:
config.IsCA = true
config.KeyCertSign = true
config.CRLSign = true
config.NotAfter = calculateValidityPeriod(config.NotBefore, config.ValidityYears, 10) // Default 10 years for CA
config.MaxPathLen = 0
case models.CertificateTypeWeb, models.CertificateTypeServer:
config.DigitalSignature = true
config.KeyEncipherment = true
config.ServerAuth = true
config.NotAfter = calculateValidityPeriodMonths(config.NotBefore, config.ValidityYears, 3) // Default 3 months for web/server
// Enterprise defaults: Use larger key size if not specified
if config.KeySize == KeySize2048 && config.ValidityYears > 1 {
config.KeySize = KeySize4096 // Use 4096 bit for enterprise certificates
}
// iOS-compatibility: Always ensure Common Name is in SAN
if config.CommonName != "" {
found := false
for _, dns := range config.DNSNames {
if dns == config.CommonName {
found = true
break
}
}
if !found {
config.DNSNames = append(config.DNSNames, config.CommonName)
}
}
// iOS-compatibility: Add Authority Information Access
config.AuthorityInfoAccess = []string{"http://ca.secnex.internal/ca.crt"}
config.IssuingCertificateURL = "http://ca.secnex.internal/ca.crt"
case models.CertificateTypeClient:
config.DigitalSignature = true
config.KeyEncipherment = true
config.ClientAuth = true
config.NotAfter = calculateValidityPeriod(config.NotBefore, config.ValidityYears, 1) // Default 1 year for client
case models.CertificateTypeEmail:
config.DigitalSignature = true
config.KeyEncipherment = true
config.EmailProtection = true
config.NotAfter = calculateValidityPeriod(config.NotBefore, config.ValidityYears, 1) // Default 1 year for email
case models.CertificateTypeCode:
config.DigitalSignature = true
config.CodeSigning = true
config.NotAfter = calculateValidityPeriod(config.NotBefore, config.ValidityYears, 2) // Default 2 years for code signing
}
return config
}
// CACertificateConfig returns a configuration specifically for CA certificates
func CACertificateConfig(isRoot bool) *CertificateConfig {
config := DefaultCertificateConfig(models.CertificateTypeCA)
config.IsCA = true
config.KeyCertSign = true
config.CRLSign = true
if isRoot {
config.NotAfter = calculateValidityPeriod(config.NotBefore, config.ValidityYears, 20) // Default 20 years for root CA
config.MaxPathLen = -1 // No limit for root CA
} else {
config.NotAfter = calculateValidityPeriod(config.NotBefore, config.ValidityYears, 10) // Default 10 years for intermediate CA
config.MaxPathLen = 0 // Intermediate CA cannot issue other CAs by default
}
return config
}
// CACertificateConfigWithValidity returns a CA configuration with custom validity period
func CACertificateConfigWithValidity(isRoot bool, validityYears int) *CertificateConfig {
config := CACertificateConfig(isRoot)
config.ValidityYears = validityYears
if isRoot {
config.NotAfter = calculateValidityPeriod(config.NotBefore, validityYears, 20)
} else {
config.NotAfter = calculateValidityPeriod(config.NotBefore, validityYears, 10)
}
return config
}
// WebServerCertificateConfig returns a configuration for web server certificates
func WebServerCertificateConfig(domains []string) *CertificateConfig {
config := DefaultCertificateConfig(models.CertificateTypeWeb)
config.DNSNames = domains
config.DigitalSignature = true
config.KeyEncipherment = true
config.ServerAuth = true
config.NotAfter = config.NotBefore.AddDate(0, 3, 0) // 3 months for web certificates
return config
}
// ClientCertificateConfig returns a configuration for client certificates
func ClientCertificateConfig() *CertificateConfig {
config := DefaultCertificateConfig(models.CertificateTypeClient)
config.DigitalSignature = true
config.KeyEncipherment = true
config.ClientAuth = true
return config
}
// EmailCertificateConfig returns a configuration for email certificates
func EmailCertificateConfig(email string) *CertificateConfig {
config := DefaultCertificateConfig(models.CertificateTypeEmail)
config.EmailAddresses = []string{email}
config.DigitalSignature = true
config.KeyEncipherment = true
config.EmailProtection = true
return config
}
// CodeSigningCertificateConfig returns a configuration for code signing certificates
func CodeSigningCertificateConfig() *CertificateConfig {
config := DefaultCertificateConfig(models.CertificateTypeCode)
config.DigitalSignature = true
config.CodeSigning = true
return config
}
// CertificateGenerator handles certificate generation
type CertificateGenerator struct {
config *CertificateConfig
}
// NewCertificateGenerator creates a new certificate generator
func NewCertificateGenerator(config *CertificateConfig) *CertificateGenerator {
return &CertificateGenerator{
config: config,
}
}
// GenerateKeyPair generates a key pair based on the configuration
func (cg *CertificateGenerator) GenerateKeyPair() (interface{}, error) {
switch cg.config.KeyType {
case KeyTypeRSA:
return rsa.GenerateKey(rand.Reader, int(cg.config.KeySize))
case KeyTypeECDSA:
var curve elliptic.Curve
switch cg.config.Curve {
case CurveP256:
curve = elliptic.P256()
case CurveP384:
curve = elliptic.P384()
case CurveP521:
curve = elliptic.P521()
default:
return nil, fmt.Errorf("unsupported ECDSA curve: %s", cg.config.Curve)
}
return ecdsa.GenerateKey(curve, rand.Reader)
default:
return nil, fmt.Errorf("unsupported key type: %s", cg.config.KeyType)
}
}
// GenerateSelfSignedCertificate generates a self-signed certificate
func (cg *CertificateGenerator) GenerateSelfSignedCertificate() (*x509.Certificate, interface{}, error) {
// Generate key pair
privateKey, err := cg.GenerateKeyPair()
if err != nil {
return nil, nil, fmt.Errorf("failed to generate key pair: %w", err)
}
// Create certificate template
template := cg.createCertificateTemplate()
// Generate certificate
certDER, err := x509.CreateCertificate(rand.Reader, template, template, cg.getPublicKey(privateKey), privateKey)
if err != nil {
return nil, nil, fmt.Errorf("failed to create certificate: %w", err)
}
// Parse certificate
cert, err := x509.ParseCertificate(certDER)
if err != nil {
return nil, nil, fmt.Errorf("failed to parse certificate: %w", err)
}
return cert, privateKey, nil
}
// GenerateCertificate generates a certificate signed by a CA
func (cg *CertificateGenerator) GenerateCertificate(caCert *x509.Certificate, caPrivateKey interface{}) (*x509.Certificate, interface{}, error) {
// Generate key pair
privateKey, err := cg.GenerateKeyPair()
if err != nil {
return nil, nil, fmt.Errorf("failed to generate key pair: %w", err)
}
// Create certificate template
template := cg.createCertificateTemplate()
// Generate certificate
certDER, err := x509.CreateCertificate(rand.Reader, template, caCert, cg.getPublicKey(privateKey), caPrivateKey)
if err != nil {
return nil, nil, fmt.Errorf("failed to create certificate: %w", err)
}
// Parse certificate
cert, err := x509.ParseCertificate(certDER)
if err != nil {
return nil, nil, fmt.Errorf("failed to parse certificate: %w", err)
}
return cert, privateKey, nil
}
// createCertificateTemplate creates an x509.Certificate template from the configuration
func (cg *CertificateGenerator) createCertificateTemplate() *x509.Certificate {
template := &x509.Certificate{
SerialNumber: cg.config.SerialNumber,
Subject: pkix.Name{
CommonName: cg.config.CommonName,
Organization: []string{cg.config.Organization},
OrganizationalUnit: []string{cg.config.OrganizationalUnit},
Country: []string{cg.config.Country},
Province: []string{cg.config.State},
Locality: []string{cg.config.Locality},
StreetAddress: []string{cg.config.Street},
PostalCode: []string{cg.config.PostalCode},
},
NotBefore: cg.config.NotBefore,
NotAfter: cg.config.NotAfter,
DNSNames: cg.config.DNSNames,
IPAddresses: cg.config.IPAddresses,
EmailAddresses: cg.config.EmailAddresses,
URIs: parseURIs(cg.config.URIs),
}
// Set key usage
var keyUsage x509.KeyUsage
if cg.config.DigitalSignature {
keyUsage |= x509.KeyUsageDigitalSignature
}
if cg.config.ContentCommitment {
keyUsage |= x509.KeyUsageContentCommitment
}
if cg.config.KeyEncipherment {
keyUsage |= x509.KeyUsageKeyEncipherment
}
if cg.config.DataEncipherment {
keyUsage |= x509.KeyUsageDataEncipherment
}
if cg.config.KeyAgreement {
keyUsage |= x509.KeyUsageKeyAgreement
}
if cg.config.KeyCertSign {
keyUsage |= x509.KeyUsageCertSign
}
if cg.config.CRLSign {
keyUsage |= x509.KeyUsageCRLSign
}
if cg.config.EncipherOnly {
keyUsage |= x509.KeyUsageEncipherOnly
}
if cg.config.DecipherOnly {
keyUsage |= x509.KeyUsageDecipherOnly
}
template.KeyUsage = keyUsage
// Set extended key usage
var extKeyUsage []x509.ExtKeyUsage
if cg.config.ServerAuth {
extKeyUsage = append(extKeyUsage, x509.ExtKeyUsageServerAuth)
}
if cg.config.ClientAuth {
extKeyUsage = append(extKeyUsage, x509.ExtKeyUsageClientAuth)
}
if cg.config.CodeSigning {
extKeyUsage = append(extKeyUsage, x509.ExtKeyUsageCodeSigning)
}
if cg.config.EmailProtection {
extKeyUsage = append(extKeyUsage, x509.ExtKeyUsageEmailProtection)
}
if cg.config.TimeStamping {
extKeyUsage = append(extKeyUsage, x509.ExtKeyUsageTimeStamping)
}
if cg.config.OCSPSigning {
extKeyUsage = append(extKeyUsage, x509.ExtKeyUsageOCSPSigning)
}
template.ExtKeyUsage = extKeyUsage
// Set basic constraints
if cg.config.BasicConstraintsValid {
template.BasicConstraintsValid = true
template.IsCA = cg.config.IsCA
if cg.config.IsCA {
template.MaxPathLen = cg.config.MaxPathLen
template.MaxPathLenZero = cg.config.MaxPathLenZero
}
}
// Set subject key identifier
if cg.config.SubjectKeyID {
template.SubjectKeyId = generateSubjectKeyID(cg.getPublicKey(nil))
}
// Set authority key identifier
if cg.config.AuthorityKeyID {
template.AuthorityKeyId = generateAuthorityKeyID(cg.getPublicKey(nil))
}
// Add CRL distribution points
if len(cg.config.CRLDistributionPoints) > 0 {
template.CRLDistributionPoints = cg.config.CRLDistributionPoints
}
// Add OCSP servers
if len(cg.config.OCSPServers) > 0 {
template.OCSPServer = cg.config.OCSPServers
}
// Add Authority Information Access (AIA) for iOS compatibility
if len(cg.config.AuthorityInfoAccess) > 0 {
template.IssuingCertificateURL = cg.config.AuthorityInfoAccess
}
return template
}
// getPublicKey extracts the public key from a private key
func (cg *CertificateGenerator) getPublicKey(privateKey interface{}) interface{} {
if privateKey == nil {
return nil
}
switch k := privateKey.(type) {
case *rsa.PrivateKey:
return &k.PublicKey
case *ecdsa.PrivateKey:
return &k.PublicKey
default:
return nil
}
}
// CertificateExporter handles certificate export functionality
type CertificateExporter struct{}
// NewCertificateExporter creates a new certificate exporter
func NewCertificateExporter() *CertificateExporter {
return &CertificateExporter{}
}
// ExportCertificateToPEM exports a certificate to PEM format
func (ce *CertificateExporter) ExportCertificateToPEM(cert *x509.Certificate) ([]byte, error) {
return pem.EncodeToMemory(&pem.Block{
Type: "CERTIFICATE",
Bytes: cert.Raw,
}), nil
}
// ExportPrivateKeyToPEM exports a private key to PEM format
func (ce *CertificateExporter) ExportPrivateKeyToPEM(privateKey interface{}) ([]byte, error) {
var pemType string
var keyBytes []byte
var err error
switch k := privateKey.(type) {
case *rsa.PrivateKey:
pemType = "RSA PRIVATE KEY"
keyBytes = x509.MarshalPKCS1PrivateKey(k)
case *ecdsa.PrivateKey:
pemType = "EC PRIVATE KEY"
keyBytes, err = x509.MarshalECPrivateKey(k)
if err != nil {
return nil, fmt.Errorf("failed to marshal ECDSA private key: %w", err)
}
default:
return nil, fmt.Errorf("unsupported private key type")
}
return pem.EncodeToMemory(&pem.Block{
Type: pemType,
Bytes: keyBytes,
}), nil
}
// ExportCertificateToDER exports a certificate to DER format
func (ce *CertificateExporter) ExportCertificateToDER(cert *x509.Certificate) []byte {
return cert.Raw
}
// ExportPrivateKeyToDER exports a private key to DER format
func (ce *CertificateExporter) ExportPrivateKeyToDER(privateKey interface{}) ([]byte, error) {
switch k := privateKey.(type) {
case *rsa.PrivateKey:
return x509.MarshalPKCS1PrivateKey(k), nil
case *ecdsa.PrivateKey:
return x509.MarshalECPrivateKey(k)
default:
return nil, fmt.Errorf("unsupported private key type")
}
}
// Utility functions
// calculateValidityPeriod calculates the validity period based on custom years or default
func calculateValidityPeriod(notBefore time.Time, customYears int, defaultYears int) time.Time {
if customYears > 0 {
return notBefore.AddDate(customYears, 0, 0)
}
return notBefore.AddDate(defaultYears, 0, 0)
}
// calculateValidityPeriodMonths calculates the validity period based on custom years or default months
func calculateValidityPeriodMonths(notBefore time.Time, customYears int, defaultMonths int) time.Time {
if customYears > 0 {
return notBefore.AddDate(customYears, 0, 0)
}
return notBefore.AddDate(0, defaultMonths, 0)
}
// generateSerialNumber generates a random serial number
func generateSerialNumber() *big.Int {
serial, _ := rand.Int(rand.Reader, new(big.Int).Lsh(big.NewInt(1), 128))
return serial
}
// generateSubjectKeyID generates a subject key identifier using SHA-256 (modern compatibility)
func generateSubjectKeyID(publicKey interface{}) []byte {
if publicKey == nil {
return nil
}
var publicKeyBytes []byte
var err error
switch k := publicKey.(type) {
case *rsa.PublicKey:
publicKeyBytes, err = asn1.Marshal(k)
case *ecdsa.PublicKey:
publicKeyBytes, err = asn1.Marshal(k)
default:
return nil
}
if err != nil {
return nil
}
// Use SHA-256 for modern compatibility (iOS + MacBook + modern browsers)
hash := sha256.Sum256(publicKeyBytes)
return hash[:]
}
// generateAuthorityKeyID generates an authority key identifier
func generateAuthorityKeyID(publicKey interface{}) []byte {
return generateSubjectKeyID(publicKey)
}
// parseURIs converts string URIs to *url.URL
func parseURIs(uriStrings []string) []*url.URL {
var uris []*url.URL
for _, uriStr := range uriStrings {
if uri, err := url.Parse(uriStr); err == nil {
uris = append(uris, uri)
}
}
return uris
}
// ParseSANs parses Subject Alternative Names from a string
func ParseSANs(sans string) ([]string, []net.IP, []string, []string) {
var dnsNames []string
var ipAddresses []net.IP
var emailAddresses []string
var uris []string
if sans == "" {
return dnsNames, ipAddresses, emailAddresses, uris
}
parts := strings.Split(sans, ",")
for _, part := range parts {
part = strings.TrimSpace(part)
if part == "" {
continue
}
// Check if it's an IP address
if ip := net.ParseIP(part); ip != nil {
ipAddresses = append(ipAddresses, ip)
continue
}
// Check if it's an email address
if strings.Contains(part, "@") {
emailAddresses = append(emailAddresses, part)
continue
}
// Check if it's a URI
if strings.HasPrefix(part, "http://") || strings.HasPrefix(part, "https://") {
uris = append(uris, part)
continue
}
// Default to DNS name
dnsNames = append(dnsNames, part)
}
return dnsNames, ipAddresses, emailAddresses, uris
}
// ValidateCertificateConfig validates a certificate configuration
func ValidateCertificateConfig(config *CertificateConfig) error {
if config.CommonName == "" {
return fmt.Errorf("common name is required")
}
if config.Organization == "" {
return fmt.Errorf("organization is required")
}
if config.Country == "" {
return fmt.Errorf("country is required")
}
if config.NotBefore.After(config.NotAfter) {
return fmt.Errorf("not before date must be before not after date")
}
if config.IsCA && !config.KeyCertSign {
return fmt.Errorf("CA certificates must have key cert sign usage")
}
// Modern browser and iOS validations
if config.CertificateType == models.CertificateTypeWeb {
// Ensure Common Name is in SAN (required by modern browsers and iOS)
if config.CommonName != "" {
found := false
for _, dns := range config.DNSNames {
if dns == config.CommonName {
found = true
break
}
}
if !found {
return fmt.Errorf("Common Name must be included in Subject Alternative Names for modern browser compatibility")
}
}
// Validate key size (minimum 2048 bits required)
if config.KeyType == KeyTypeRSA && config.KeySize < KeySize2048 {
return fmt.Errorf("RSA keys must be at least 2048 bits")
}
// Validate validity period (maximum 825 days, recommended 398 days)
validityDays := int(config.NotAfter.Sub(config.NotBefore).Hours() / 24)
if validityDays > 825 {
return fmt.Errorf("certificate validity period exceeds 825 days (current: %d days)", validityDays)
}
}
return nil
}
// CreateCertificateFromModel creates a certificate configuration from a model
func CreateCertificateFromModel(cert *models.Certificate) *CertificateConfig {
config := DefaultCertificateConfig(cert.Type)
config.CommonName = cert.AttributeCommonName
config.Organization = cert.AttributeOrganization
config.OrganizationalUnit = cert.AttributeOrganizationUnit
config.Country = cert.AttributeCountry
config.State = cert.AttributeState
config.Locality = cert.AttributeLocality
config.Street = cert.AttributeStreet
config.PostalCode = cert.AttributePostalCode
config.Email = cert.AttributeEmail
config.NotBefore = cert.AttributeNotBefore
config.NotAfter = cert.AttributeNotAfter
// Parse SANs
if cert.AttributeSubjectAlternativeName != "" {
dnsNames, ipAddresses, emailAddresses, uris := ParseSANs(cert.AttributeSubjectAlternativeName)
config.DNSNames = dnsNames
config.IPAddresses = ipAddresses
config.EmailAddresses = emailAddresses
config.URIs = uris
}
return config
}
// CreateCAFromModel creates a CA configuration from a model
func CreateCAFromModel(ca *models.CertificateAuthority) *CertificateConfig {
config := CACertificateConfig(ca.Root)
config.CommonName = ca.AttributeCommonName
config.Organization = ca.AttributeOrganization
config.OrganizationalUnit = ca.AttributeOrganizationUnit
config.Country = ca.AttributeCountry
config.State = ca.AttributeState
config.Locality = ca.AttributeLocality
config.Street = ca.AttributeStreet
config.PostalCode = ca.AttributePostalCode
config.Email = ca.AttributeEmail
config.NotBefore = ca.AttributeNotBefore
config.NotAfter = ca.AttributeNotAfter
return config
}