Regex 从证书PEM字符串开始和结束的trip正则表达式

证书PEM文件包含以下开头和结尾：

-----BEGIN CERTIFICATE----- [Base64 of certificate] -----END CERTIFICATE

我只需要提取

[Base64 of certificate]

部分，即去掉

“----开始证书-----”

和

“----结束证书-----”

字符串，我想知道这是否可以用正则表达式来完成，如果可以，正则表达式会是什么样子

我试过：

-----BEGIN CERTIFICATE----- (.*) -----END CERTIFICATE-----

但是，它没有给我证书的Base64，而是返回了所有内容

谢谢，

---

Jim

因为我不知道您使用的语言，我给您提供了一个相对可移植的模式（必须支持向前看和向后看）：

---

（？因为我不知道您使用的语言，所以我给您提供了一个相对可移植的模式（必须支持向前看和向后看）：

（？以下是支持您的需求的示例perl代码

my $Str = "-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----";
if($Str =~ /^\W+\w+\s+\w+\W+\s(.*)\s+\W+.*$/s) {
    print "$1" . "\n\n";
} else {
    print "No\n" . "\n\n";
}

输出：
下面是支持您的需求的示例perl代码

my $Str = "-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----";
if($Str =~ /^\W+\w+\s+\w+\W+\s(.*)\s+\W+.*$/s) {
    print "$1" . "\n\n";
} else {
    print "No\n" . "\n\n";
}

输出：
在perl中：

my base64_cert_data;
if ($certbuf=~/(-+BEGIN CERTIFICATE-+)(.*?)(-+END CERTIFICATE-+)/s) {
    base64_cert_data = $2;
}

正则表达式解释：

/(-+BEGIN CERTIFICATE-+)(.*?)(-+END CERTIFICATE-+)/s

1st Capturing group (-+BEGIN CERTIFICATE-+)
    -+ matches the character - literally
        Quantifier: + Between one and unlimited times, as many times as possible, giving back as needed [greedy]
    BEGIN CERTIFICATE matches the characters BEGIN CERTIFICATE literally (case sensitive)
    -+ matches the character - literally
        Quantifier: + Between one and unlimited times, as many times as possible, giving back as needed [greedy]
2nd Capturing group (.*?)
    .*? matches any character
        Quantifier: *? Between zero and unlimited times, as few times as possible, expanding as needed [lazy]
3rd Capturing group (-+END CERTIFICATE-+)
    -+ matches the character - literally
        Quantifier: + Between one and unlimited times, as many times as possible, giving back as needed [greedy]
    END CERTIFICATE matches the characters END CERTIFICATE literally (case sensitive)
    -+ matches the character - literally
        Quantifier: + Between one and unlimited times, as many times as possible, giving back as needed [greedy]
s modifier: single line. Dot matches newline characters

在perl中：

my base64_cert_data;
if ($certbuf=~/(-+BEGIN CERTIFICATE-+)(.*?)(-+END CERTIFICATE-+)/s) {
    base64_cert_data = $2;
}

正则表达式解释：

/(-+BEGIN CERTIFICATE-+)(.*?)(-+END CERTIFICATE-+)/s

1st Capturing group (-+BEGIN CERTIFICATE-+)
    -+ matches the character - literally
        Quantifier: + Between one and unlimited times, as many times as possible, giving back as needed [greedy]
    BEGIN CERTIFICATE matches the characters BEGIN CERTIFICATE literally (case sensitive)
    -+ matches the character - literally
        Quantifier: + Between one and unlimited times, as many times as possible, giving back as needed [greedy]
2nd Capturing group (.*?)
    .*? matches any character
        Quantifier: *? Between zero and unlimited times, as few times as possible, expanding as needed [lazy]
3rd Capturing group (-+END CERTIFICATE-+)
    -+ matches the character - literally
        Quantifier: + Between one and unlimited times, as many times as possible, giving back as needed [greedy]
    END CERTIFICATE matches the characters END CERTIFICATE literally (case sensitive)
    -+ matches the character - literally
        Quantifier: + Between one and unlimited times, as many times as possible, giving back as needed [greedy]
s modifier: single line. Dot matches newline characters

base64字符集是：

[A-Za-z0-9+/\r\n]+={0,2}
-这是对PEM文件（base64证书）通常使用的内容的准确描述。
=
用于填充（在末尾），
\r\n
是新行字符

综合起来，我们得到：

“-+BEGIN\\s+.*证书[^-]*-+（？：\\s |\\r |\\n）+”//头
+“（[A-Za-z0-9+/\r\n]+={0,2}）”///Base64文本
+“-+END\\s+.*证书[^-]*-+”//页脚

如果您想成为语言不可知论者，您可以期望页眉/页脚是一个或多个
-
字符，后面紧跟着大写字母，然后是一个或多个
-
字符。
base64字符集是：

[A-Za-z0-9+/\r\n]+={0,2}
-这是对PEM文件（base64证书）通常使用的内容的准确描述。
=
用于填充（在末尾），
\r\n
是新行字符

综合起来，我们得到：

“-+BEGIN\\s+.*证书[^-]*-+（？：\\s |\\r |\\n）+”//头
+“（[A-Za-z0-9+/\r\n]+={0,2}）”///Base64文本
+“-+END\\s+.*证书[^-]*-+”//页脚

如果你想成为语言不可知论者，你可以期望页眉/页脚是一个或多个
-
字符，后跟大写字母，再加上一个或多个
-
字符。
你使用什么语言？鉴于-不会出现在主base64块的任何地方，我在java中的理解是：str=str.replaceAll（“-+.[A-Z]+-+”，”）-这还包括CSR和键等其他内容。您使用哪种语言？鉴于它不会出现在主base64块中的任何位置，我在java中对此的理解是：str=str.replaceAll（“-+.[A-Z]+-+”，”）-这还包括CSR和密钥等其他内容。在查看一些问题时，这是验证base64编码的唯一尝试。我仍然需要修改一点以'-+开始[a-zA-Z]*-+\\n[a-zA-z0-9\/\\n+]+-+结束[a-zA-Z]*-+\\n'。然后我再次检查密钥而不是证书。在某些编程语言中，您可以完全忽略区分大小写以简化一些事情。密钥通常在页眉/页脚中有证书，并且密钥将有密钥。在查看一些问题时，这是验证base64编码的唯一尝试。我仍然需要修改有点“-+开始[a-zA-Z]*-+\\n[a-zA-z0-9\/\\n+]+-+结束[a-zA-Z]*-+\\n”。然后我再次检查密钥而不是证书。在某些编程语言中，可以完全忽略大小写敏感度以简化一些事情。密钥通常在页眉/页脚中有证书，而密钥将有密钥。