open-vault/builtin/logical/transit/path_sign_verify.go
Jeff Mitchell 76b0d11793
Redo transit locking (#4720)
This massively simplifies transit locking behavior by pushing some
locking down to the Policy level, and embedding either a local or global
lock in the Policy depending on whether caching is enabled or not.
2018-06-12 12:24:12 -04:00

372 lines
10 KiB
Go

package transit
import (
"context"
"crypto/sha256"
"crypto/sha512"
"encoding/base64"
"fmt"
"hash"
"github.com/hashicorp/vault/helper/errutil"
"github.com/hashicorp/vault/helper/keysutil"
"github.com/hashicorp/vault/logical"
"github.com/hashicorp/vault/logical/framework"
)
func (b *backend) pathSign() *framework.Path {
return &framework.Path{
Pattern: "sign/" + framework.GenericNameRegex("name") + framework.OptionalParamRegex("urlalgorithm"),
Fields: map[string]*framework.FieldSchema{
"name": &framework.FieldSchema{
Type: framework.TypeString,
Description: "The key to use",
},
"input": &framework.FieldSchema{
Type: framework.TypeString,
Description: "The base64-encoded input data",
},
"context": &framework.FieldSchema{
Type: framework.TypeString,
Description: `Base64 encoded context for key derivation. Required if key
derivation is enabled; currently only available with ed25519 keys.`,
},
"hash_algorithm": &framework.FieldSchema{
Type: framework.TypeString,
Default: "sha2-256",
Description: `Hash algorithm to use (POST body parameter). Valid values are:
* sha2-224
* sha2-256
* sha2-384
* sha2-512
Defaults to "sha2-256". Not valid for all key types,
including ed25519.`,
},
"algorithm": &framework.FieldSchema{
Type: framework.TypeString,
Default: "sha2-256",
Description: `Deprecated: use "hash_algorithm" instead.`,
},
"urlalgorithm": &framework.FieldSchema{
Type: framework.TypeString,
Description: `Hash algorithm to use (POST URL parameter)`,
},
"key_version": &framework.FieldSchema{
Type: framework.TypeInt,
Description: `The version of the key to use for signing.
Must be 0 (for latest) or a value greater than or equal
to the min_encryption_version configured on the key.`,
},
"prehashed": &framework.FieldSchema{
Type: framework.TypeBool,
Description: `Set to 'true' when the input is already hashed. If the key type is 'rsa-2048' or 'rsa-4096', then the algorithm used to hash the input should be indicated by the 'algorithm' parameter.`,
},
"signature_algorithm": &framework.FieldSchema{
Type: framework.TypeString,
Description: `The signature algorithm to use for signing. Currently only applies to RSA key types.
Options are 'pss' or 'pkcs1v15'. Defaults to 'pss'`,
},
},
Callbacks: map[logical.Operation]framework.OperationFunc{
logical.UpdateOperation: b.pathSignWrite,
},
HelpSynopsis: pathSignHelpSyn,
HelpDescription: pathSignHelpDesc,
}
}
func (b *backend) pathVerify() *framework.Path {
return &framework.Path{
Pattern: "verify/" + framework.GenericNameRegex("name") + framework.OptionalParamRegex("urlalgorithm"),
Fields: map[string]*framework.FieldSchema{
"name": &framework.FieldSchema{
Type: framework.TypeString,
Description: "The key to use",
},
"context": &framework.FieldSchema{
Type: framework.TypeString,
Description: `Base64 encoded context for key derivation. Required if key
derivation is enabled; currently only available with ed25519 keys.`,
},
"signature": &framework.FieldSchema{
Type: framework.TypeString,
Description: "The signature, including vault header/key version",
},
"hmac": &framework.FieldSchema{
Type: framework.TypeString,
Description: "The HMAC, including vault header/key version",
},
"input": &framework.FieldSchema{
Type: framework.TypeString,
Description: "The base64-encoded input data to verify",
},
"urlalgorithm": &framework.FieldSchema{
Type: framework.TypeString,
Description: `Hash algorithm to use (POST URL parameter)`,
},
"hash_algorithm": &framework.FieldSchema{
Type: framework.TypeString,
Default: "sha2-256",
Description: `Hash algorithm to use (POST body parameter). Valid values are:
* sha2-224
* sha2-256
* sha2-384
* sha2-512
Defaults to "sha2-256". Not valid for all key types.`,
},
"algorithm": &framework.FieldSchema{
Type: framework.TypeString,
Default: "sha2-256",
Description: `Deprecated: use "hash_algorithm" instead.`,
},
"prehashed": &framework.FieldSchema{
Type: framework.TypeBool,
Description: `Set to 'true' when the input is already hashed. If the key type is 'rsa-2048' or 'rsa-4096', then the algorithm used to hash the input should be indicated by the 'algorithm' parameter.`,
},
"signature_algorithm": &framework.FieldSchema{
Type: framework.TypeString,
Description: `The signature algorithm to use for signature verification. Currently only applies to RSA key types.
Options are 'pss' or 'pkcs1v15'. Defaults to 'pss'`,
},
},
Callbacks: map[logical.Operation]framework.OperationFunc{
logical.UpdateOperation: b.pathVerifyWrite,
},
HelpSynopsis: pathVerifyHelpSyn,
HelpDescription: pathVerifyHelpDesc,
}
}
func (b *backend) pathSignWrite(ctx context.Context, req *logical.Request, d *framework.FieldData) (*logical.Response, error) {
name := d.Get("name").(string)
ver := d.Get("key_version").(int)
inputB64 := d.Get("input").(string)
hashAlgorithm := d.Get("urlalgorithm").(string)
if hashAlgorithm == "" {
hashAlgorithm = d.Get("hash_algorithm").(string)
if hashAlgorithm == "" {
hashAlgorithm = d.Get("algorithm").(string)
}
}
prehashed := d.Get("prehashed").(bool)
sigAlgorithm := d.Get("signature_algorithm").(string)
input, err := base64.StdEncoding.DecodeString(inputB64)
if err != nil {
return logical.ErrorResponse(fmt.Sprintf("unable to decode input as base64: %s", err)), logical.ErrInvalidRequest
}
// Get the policy
p, _, err := b.lm.GetPolicy(ctx, keysutil.PolicyRequest{
Storage: req.Storage,
Name: name,
})
if err != nil {
return nil, err
}
if p == nil {
return logical.ErrorResponse("encryption key not found"), logical.ErrInvalidRequest
}
if !b.System().CachingDisabled() {
p.Lock(false)
}
if !p.Type.SigningSupported() {
p.Unlock()
return logical.ErrorResponse(fmt.Sprintf("key type %v does not support signing", p.Type)), logical.ErrInvalidRequest
}
contextRaw := d.Get("context").(string)
var context []byte
if len(contextRaw) != 0 {
context, err = base64.StdEncoding.DecodeString(contextRaw)
if err != nil {
p.Unlock()
return logical.ErrorResponse("failed to base64-decode context"), logical.ErrInvalidRequest
}
}
if p.Type.HashSignatureInput() && !prehashed {
var hf hash.Hash
switch hashAlgorithm {
case "sha2-224":
hf = sha256.New224()
case "sha2-256":
hf = sha256.New()
case "sha2-384":
hf = sha512.New384()
case "sha2-512":
hf = sha512.New()
default:
p.Unlock()
return logical.ErrorResponse(fmt.Sprintf("unsupported hash algorithm %s", hashAlgorithm)), nil
}
hf.Write(input)
input = hf.Sum(nil)
}
sig, err := p.Sign(ver, context, input, hashAlgorithm, sigAlgorithm)
if err != nil {
p.Unlock()
return nil, err
}
if sig == nil {
p.Unlock()
return nil, fmt.Errorf("signature could not be computed")
}
// Generate the response
resp := &logical.Response{
Data: map[string]interface{}{
"signature": sig.Signature,
},
}
if len(sig.PublicKey) > 0 {
resp.Data["public_key"] = sig.PublicKey
}
p.Unlock()
return resp, nil
}
func (b *backend) pathVerifyWrite(ctx context.Context, req *logical.Request, d *framework.FieldData) (*logical.Response, error) {
sig := d.Get("signature").(string)
hmac := d.Get("hmac").(string)
switch {
case sig != "" && hmac != "":
return logical.ErrorResponse("provide one of 'signature' or 'hmac'"), logical.ErrInvalidRequest
case sig == "" && hmac == "":
return logical.ErrorResponse("neither a 'signature' nor an 'hmac' were given to verify"), logical.ErrInvalidRequest
case hmac != "":
return b.pathHMACVerify(ctx, req, d, hmac)
}
name := d.Get("name").(string)
inputB64 := d.Get("input").(string)
hashAlgorithm := d.Get("urlalgorithm").(string)
if hashAlgorithm == "" {
hashAlgorithm = d.Get("hash_algorithm").(string)
if hashAlgorithm == "" {
hashAlgorithm = d.Get("algorithm").(string)
}
}
prehashed := d.Get("prehashed").(bool)
sigAlgorithm := d.Get("signature_algorithm").(string)
input, err := base64.StdEncoding.DecodeString(inputB64)
if err != nil {
return logical.ErrorResponse(fmt.Sprintf("unable to decode input as base64: %s", err)), logical.ErrInvalidRequest
}
// Get the policy
p, _, err := b.lm.GetPolicy(ctx, keysutil.PolicyRequest{
Storage: req.Storage,
Name: name,
})
if err != nil {
return nil, err
}
if p == nil {
return logical.ErrorResponse("encryption key not found"), logical.ErrInvalidRequest
}
if !b.System().CachingDisabled() {
p.Lock(false)
}
if !p.Type.SigningSupported() {
p.Unlock()
return logical.ErrorResponse(fmt.Sprintf("key type %v does not support verification", p.Type)), logical.ErrInvalidRequest
}
contextRaw := d.Get("context").(string)
var context []byte
if len(contextRaw) != 0 {
context, err = base64.StdEncoding.DecodeString(contextRaw)
if err != nil {
p.Unlock()
return logical.ErrorResponse("failed to base64-decode context"), logical.ErrInvalidRequest
}
}
if p.Type.HashSignatureInput() && !prehashed {
var hf hash.Hash
switch hashAlgorithm {
case "sha2-224":
hf = sha256.New224()
case "sha2-256":
hf = sha256.New()
case "sha2-384":
hf = sha512.New384()
case "sha2-512":
hf = sha512.New()
default:
p.Unlock()
return logical.ErrorResponse(fmt.Sprintf("unsupported hash algorithm %s", hashAlgorithm)), nil
}
hf.Write(input)
input = hf.Sum(nil)
}
valid, err := p.VerifySignature(context, input, sig, hashAlgorithm, sigAlgorithm)
if err != nil {
switch err.(type) {
case errutil.UserError:
p.Unlock()
return logical.ErrorResponse(err.Error()), logical.ErrInvalidRequest
case errutil.InternalError:
p.Unlock()
return nil, err
default:
p.Unlock()
return nil, err
}
}
// Generate the response
resp := &logical.Response{
Data: map[string]interface{}{
"valid": valid,
},
}
p.Unlock()
return resp, nil
}
const pathSignHelpSyn = `Generate a signature for input data using the named key`
const pathSignHelpDesc = `
Generates a signature of the input data using the named key and the given hash algorithm.
`
const pathVerifyHelpSyn = `Verify a signature or HMAC for input data created using the named key`
const pathVerifyHelpDesc = `
Verifies a signature or HMAC of the input data using the named key and the given hash algorithm.
`