mirror of
https://github.com/cheat/cheat.git
synced 2024-12-18 18:55:06 +01:00
27 lines
847 B
Go
27 lines
847 B
Go
package s2k
|
|
|
|
// Cache stores keys derived with s2k functions from one passphrase
|
|
// to avoid recomputation if multiple items are encrypted with
|
|
// the same parameters.
|
|
type Cache map[Params][]byte
|
|
|
|
// GetOrComputeDerivedKey tries to retrieve the key
|
|
// for the given s2k parameters from the cache.
|
|
// If there is no hit, it derives the key with the s2k function from the passphrase,
|
|
// updates the cache, and returns the key.
|
|
func (c *Cache) GetOrComputeDerivedKey(passphrase []byte, params *Params, expectedKeySize int) ([]byte, error) {
|
|
key, found := (*c)[*params]
|
|
if !found || len(key) != expectedKeySize {
|
|
var err error
|
|
derivedKey := make([]byte, expectedKeySize)
|
|
s2k, err := params.Function()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
s2k(derivedKey, passphrase)
|
|
(*c)[*params] = key
|
|
return derivedKey, nil
|
|
}
|
|
return key, nil
|
|
}
|