pem

pem

https://pkg.go.dev/encoding/pem@go1.20.1

​ pem包实现了PEM数据编码,该编码起源于隐私增强邮件(Privacy Enhanced Mail)。如今,PEM编码最常用于TLS密钥和证书。详见RFC 1421

常量

This section is empty.

变量

This section is empty.

函数

func Encode

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func Encode(out io.Writer, b *Block) error

​ Encode函数将b的PEM编码写入out

Encode Example
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package main

import (
	"encoding/pem"
	"log"
	"os"
)

func main() {
	block := &pem.Block{
		Type: "MESSAGE",
		Headers: map[string]string{
			"Animal": "Gopher",
		},
		Bytes: []byte("test"),
	}

	if err := pem.Encode(os.Stdout, block); err != nil {
		log.Fatal(err)
	}
}
Output:

-----BEGIN MESSAGE-----
Animal: Gopher

dGVzdA==
-----END MESSAGE-----

func EncodeToMemory

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func EncodeToMemory(b *Block) []byte

​ EncodeToMemory函数返回b的PEM编码。

​ 如果b具有无效的标头且无法被编码,EncodeToMemory函数返回nil。如果报告这种错误情况的细节很重要,请使用Encode代替。

类型

type Block

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type Block struct {
	Type    string            // The type, taken from the preamble (i.e. "RSA PRIVATE KEY").// 类型,取自序言(即 "RSA PRIVATE KEY")。
	Headers map[string]string // 可选的头信息。
	Bytes   []byte            // The decoded bytes of the contents. Typically a DER encoded ASN.1 structure. // 解码后的内容字节。通常是一个DER编码的ASN.1结构。
}

​ Block表示一个PEM编码的结构。

​ 其编码后的形式是:

-----BEGIN Type-----
Headers
base64-encoded Bytes
-----END Type-----

​ 其中Headers是一个可能是空的Key: Value行序列。

func Decode

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func Decode(data []byte) (p *Block, rest []byte)

​ Decode函数会在输入中查找下一个PEM格式的块(证书、私钥等)。它返回该块以及剩余的输入。如果未找到PEM数据,p为nil,并将整个输入返回给rest

Decode Example
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package main

import (
	"crypto/x509"
	"encoding/pem"
	"fmt"
	"log"
)

func main() {
	var pubPEMData = []byte(`
-----BEGIN PUBLIC KEY-----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-----END PUBLIC KEY-----
and some more`)

	block, rest := pem.Decode(pubPEMData)
	if block == nil || block.Type != "PUBLIC KEY" {
		log.Fatal("failed to decode PEM block containing public key")
	}

	pub, err := x509.ParsePKIXPublicKey(block.Bytes)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Printf("Got a %T, with remaining data: %q", pub, rest)
}

Output:

Got a *rsa.PublicKey, with remaining data: "and some more"