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Package sha256

import "crypto/sha256"

Overview ▸

Overview ▾

Package sha256 implements the SHA224 and SHA256 hash algorithms as defined in FIPS 180-4.

Index ▸

Index ▾

func New() hash.Hash

func New224() hash.Hash

func Sum224(data []byte) [Size224]byte

func Sum256(data []byte) [Size]byte

Examples (Expand All)

Package files

sha256.go sha256block.go sha256block_amd64.go sha256block_decl.go

Constants

The blocksize of SHA256 and SHA224 in bytes.

const BlockSize = 64

The size of a SHA256 checksum in bytes.

const Size = 32

The size of a SHA224 checksum in bytes.

const Size224 = 28

func New ¶

func New() hash.Hash

New returns a new hash.Hash computing the SHA256 checksum. The Hash also implements encoding.BinaryMarshaler and encoding.BinaryUnmarshaler to marshal and unmarshal the internal state of the hash.

▸ Example

▾ Example

package main

import (
	"crypto/sha256"
	"fmt"
)

func main() {
	h := sha256.New()
	h.Write([]byte("hello world\n"))
	fmt.Printf("%x", h.Sum(nil))
}

a948904f2f0f479b8f8197694b30184b0d2ed1c1cd2a1ec0fb85d299a192a447

▸ Example (File)

▾ Example (File)

package main

import (
	"crypto/sha256"
	"fmt"
	"io"
	"log"
	"os"
)

func main() {
	f, err := os.Open("file.txt")
	if err != nil {
		log.Fatal(err)
	}
	defer f.Close()

	h := sha256.New()
	if _, err := io.Copy(h, f); err != nil {
		log.Fatal(err)
	}

	fmt.Printf("%x", h.Sum(nil))
}

func New224 ¶

func New224() hash.Hash

New224 returns a new hash.Hash computing the SHA224 checksum.

func Sum224 ¶ 1.2

func Sum224(data []byte) [Size224]byte

Sum224 returns the SHA224 checksum of the data.

func Sum256 ¶ 1.2

func Sum256(data []byte) [Size]byte

Sum256 returns the SHA256 checksum of the data.

▸ Example

▾ Example

package main

import (
	"crypto/sha256"
	"fmt"
)

func main() {
	sum := sha256.Sum256([]byte("hello world\n"))
	fmt.Printf("%x", sum)
}

a948904f2f0f479b8f8197694b30184b0d2ed1c1cd2a1ec0fb85d299a192a447