README
¶
Random
Interface for random number generators.
Overview
Provides an interface for all random number generators used by holster/secret. Allows
random number generation to be done in one place as well as faking random
numbers when predictable output is required (like in tests).
The cryptographically secure pseudo-random number generator (CSPRNG) used is /dev/urandom.
Generate a n-bit random number
import (
"fmt"
"github.com/mailgun/holster/random"
)
outputSize = 16 // 128 bit = 16 byte
csprng := random.CSPRNG{}
// hex-encoded random bytes
randomHexDigest, err := csprng.HexDigest(outputSize)
fmt.Printf("Random Hex Digest: %v, err: %v\n", randomHexDigest, err)
// raw bytes
randomBytes, err := csprng.Bytes(outputSize)
fmt.Printf("Random Bytes: %# x, err: %v\n", randomBytes, err)
// Output: Random Hex Digest: 45eb93fdf5afe149ee3e61412c97e9bc, err: <nil>
// Random Bytes: 0xee 0x52 0x5b 0x50 0xb9 0x10 0x3c 0x14 0x75 0x9a 0xa5 0xb9 0xa3 0xc4 0x6e 0x50, err: <nil>
Generate a fake n-bit random number
import (
"fmt"
"github.com/mailgun/holster/random"
)
outputSize = 16 // 128 bit = 16 byte
fakerng := random.FakeRNG{}
// (fake) hex-encoded random bytes
fakeRandomHexDigest := fakerng.HexDigest(outputSize)
fmt.Printf("(Fake) Random Hex Digest: %v\n", fakeHexDigest)
// (fake) raw bytes
fakeRandomBytes := fakerng.Bytes(outputSize)
fmt.Printf("(Fake) Random Bytes: %# x\n", fakeRandomBytes)
// Output: Random Hex Digest: 0102030405060708090A0B0C0E0F1011
// Random Bytes: 0x00 0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08 0x09 0x0a 0x0b 0x0c 0x0d 0x0e 0x0f
Documentation
¶
Overview ¶
Copyright 2017 Mailgun Technologies Inc
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type CSPRNG ¶
type CSPRNG struct{}
Real random values, used in production
type FakeRNG ¶
type FakeRNG struct{}
Fake random, used in tests. never use this in production!
type RandomProvider ¶
type RandomProvider interface {
Bytes(bytes int) ([]byte, error)
HexDigest(bytes int) (string, error)
}
Interface for our random number generator. We need this to fake random values in tests.
type SeededRNG ¶
type SeededRNG struct {
Seed int64
// contains filtered or unexported fields
}
SeededRNG returns bytes generated in a predictable sequence by package math/rand. Not cryptographically secure, not thread safe. Changes to Seed after the first call to Bytes or HexDigest will have no effect. The zero value of SeededRNG is ready to use, and will use a seed of 0.
Source Files