diff options
Diffstat (limited to 'vendor/github.com/miekg/dns/dnssec_keygen.go')
-rw-r--r-- | vendor/github.com/miekg/dns/dnssec_keygen.go | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/vendor/github.com/miekg/dns/dnssec_keygen.go b/vendor/github.com/miekg/dns/dnssec_keygen.go new file mode 100644 index 000000000..229a07937 --- /dev/null +++ b/vendor/github.com/miekg/dns/dnssec_keygen.go @@ -0,0 +1,156 @@ +package dns + +import ( + "crypto" + "crypto/dsa" + "crypto/ecdsa" + "crypto/elliptic" + "crypto/rand" + "crypto/rsa" + "math/big" +) + +// Generate generates a DNSKEY of the given bit size. +// The public part is put inside the DNSKEY record. +// The Algorithm in the key must be set as this will define +// what kind of DNSKEY will be generated. +// The ECDSA algorithms imply a fixed keysize, in that case +// bits should be set to the size of the algorithm. +func (k *DNSKEY) Generate(bits int) (crypto.PrivateKey, error) { + switch k.Algorithm { + case DSA, DSANSEC3SHA1: + if bits != 1024 { + return nil, ErrKeySize + } + case RSAMD5, RSASHA1, RSASHA256, RSASHA1NSEC3SHA1: + if bits < 512 || bits > 4096 { + return nil, ErrKeySize + } + case RSASHA512: + if bits < 1024 || bits > 4096 { + return nil, ErrKeySize + } + case ECDSAP256SHA256: + if bits != 256 { + return nil, ErrKeySize + } + case ECDSAP384SHA384: + if bits != 384 { + return nil, ErrKeySize + } + } + + switch k.Algorithm { + case DSA, DSANSEC3SHA1: + params := new(dsa.Parameters) + if err := dsa.GenerateParameters(params, rand.Reader, dsa.L1024N160); err != nil { + return nil, err + } + priv := new(dsa.PrivateKey) + priv.PublicKey.Parameters = *params + err := dsa.GenerateKey(priv, rand.Reader) + if err != nil { + return nil, err + } + k.setPublicKeyDSA(params.Q, params.P, params.G, priv.PublicKey.Y) + return priv, nil + case RSAMD5, RSASHA1, RSASHA256, RSASHA512, RSASHA1NSEC3SHA1: + priv, err := rsa.GenerateKey(rand.Reader, bits) + if err != nil { + return nil, err + } + k.setPublicKeyRSA(priv.PublicKey.E, priv.PublicKey.N) + return priv, nil + case ECDSAP256SHA256, ECDSAP384SHA384: + var c elliptic.Curve + switch k.Algorithm { + case ECDSAP256SHA256: + c = elliptic.P256() + case ECDSAP384SHA384: + c = elliptic.P384() + } + priv, err := ecdsa.GenerateKey(c, rand.Reader) + if err != nil { + return nil, err + } + k.setPublicKeyECDSA(priv.PublicKey.X, priv.PublicKey.Y) + return priv, nil + default: + return nil, ErrAlg + } +} + +// Set the public key (the value E and N) +func (k *DNSKEY) setPublicKeyRSA(_E int, _N *big.Int) bool { + if _E == 0 || _N == nil { + return false + } + buf := exponentToBuf(_E) + buf = append(buf, _N.Bytes()...) + k.PublicKey = toBase64(buf) + return true +} + +// Set the public key for Elliptic Curves +func (k *DNSKEY) setPublicKeyECDSA(_X, _Y *big.Int) bool { + if _X == nil || _Y == nil { + return false + } + var intlen int + switch k.Algorithm { + case ECDSAP256SHA256: + intlen = 32 + case ECDSAP384SHA384: + intlen = 48 + } + k.PublicKey = toBase64(curveToBuf(_X, _Y, intlen)) + return true +} + +// Set the public key for DSA +func (k *DNSKEY) setPublicKeyDSA(_Q, _P, _G, _Y *big.Int) bool { + if _Q == nil || _P == nil || _G == nil || _Y == nil { + return false + } + buf := dsaToBuf(_Q, _P, _G, _Y) + k.PublicKey = toBase64(buf) + return true +} + +// Set the public key (the values E and N) for RSA +// RFC 3110: Section 2. RSA Public KEY Resource Records +func exponentToBuf(_E int) []byte { + var buf []byte + i := big.NewInt(int64(_E)) + if len(i.Bytes()) < 256 { + buf = make([]byte, 1) + buf[0] = uint8(len(i.Bytes())) + } else { + buf = make([]byte, 3) + buf[0] = 0 + buf[1] = uint8(len(i.Bytes()) >> 8) + buf[2] = uint8(len(i.Bytes())) + } + buf = append(buf, i.Bytes()...) + return buf +} + +// Set the public key for X and Y for Curve. The two +// values are just concatenated. +func curveToBuf(_X, _Y *big.Int, intlen int) []byte { + buf := intToBytes(_X, intlen) + buf = append(buf, intToBytes(_Y, intlen)...) + return buf +} + +// Set the public key for X and Y for Curve. The two +// values are just concatenated. +func dsaToBuf(_Q, _P, _G, _Y *big.Int) []byte { + t := divRoundUp(divRoundUp(_G.BitLen(), 8)-64, 8) + buf := []byte{byte(t)} + buf = append(buf, intToBytes(_Q, 20)...) + buf = append(buf, intToBytes(_P, 64+t*8)...) + buf = append(buf, intToBytes(_G, 64+t*8)...) + buf = append(buf, intToBytes(_Y, 64+t*8)...) + return buf +} |