split -d -p "BEGIN CERTIFICATE" collection.pem pem-
例
$ cat ssl.crt -----BEGIN CERTIFICATE----- MIIFJTCCBA2gAwIBAgISBDQTF4tkOl1xOEFjwYVzvtpGMA0GCSqGSIb3DQEBCwUA MDIxCzAJBgNVBAYTAlVTMRYwFAYDVQQKEw1MZXQncyBFbmNyeXB0MQswCQYDVQQD EwJSMzAeFw0yMzA4MDIwMDI1NTJaFw0yMzEwMzEwMDI1NTFaMCcxJTAjBgNVBAMT HGt5YW5ueS0xNjkwOTM5MDQ5LnFhYm9vdC5uZXQwggEiMA0GCSqGSIb3DQEBAQUA A4IBDwAwggEKAoIBAQCXNXXtaLl6jsyiUMGTWBOfCpwv5G7znkFyAatUkhmo6yfd +v+LX20Iisl76022fDwjf3ZYOXGQuticZ+yrB9eeDsgvQDuppXB0BHHQmr1Oe+O1 rrO6iNntTi3iLmRa08CU8V5gNe3LWQ0iwUU2ZCUDVos5G1kLFJwbmPdVuqk/pfZ9 hJajxkCnyE75HKf9VvA/YHcDvknB3qXfDdqQb3uq4P2h7hOe/oH+iMCZXiML0OAG XczWtuJvcemFSiNHHmNC3eHAnTKCBEnSo1kgjC1MJbanUvVJ0H/GJpEwYnshP9a7 1yMZp3J64wKXRDF8F3pp0zsuBy8XNkw9xKUh2UDDAgMBAAGjggI+MIICOjAOBgNV HQ8BAf8EBAMCBaAwHQYDVR0lBBYwFAYIKwYBBQUHAwEGCCsGAQUFBwMCMAwGA1Ud EwEB/wQCMAAwHQYDVR0OBBYEFCw5T1pV8oWTDLBVf7Z815J3BS4XMB8GA1UdIwQY MBaAFBQusxe3WFbLrlAJQOYfr52LFMLGMFUGCCsGAQUFBwEBBEkwRzAhBggrBgEF BQcwAYYVaHR0cDovL3IzLm8ubGVuY3Iub3JnMCIGCCsGAQUFBzAChhZodHRwOi8v cjMuaS5sZW5jci5vcmcvMEcGA1UdEQRAMD6CHioua3lhbm55LTE2OTA5MzkwNDku cWFib290Lm5ldIIca3lhbm55LTE2OTA5MzkwNDkucWFib290Lm5ldDATBgNVHSAE DDAKMAgGBmeBDAECATCCAQQGCisGAQQB1nkCBAIEgfUEgfIA8AB3ALc++yTfnE26 dfI5xbpY9Gxd/ELPep81xJ4dCYEl7bSZAAABibPZ9WMAAAQDAEgwRgIhAJD38ucl 1j104Pi1fuvy8t/FpfY7/GbIiJTeHyv1WIaUAiEA+P8UDWg3Je3WDAvoGzhEilzV Z9kioy78irS4libfkfMAdQCt9776fP8QyIudPZwePhhqtGcpXc+xDCTKhYY069yC igAAAYmz2fWZAAAEAwBGMEQCICOu4anjPJx503dLcckQzJOqbQ1T46NwmxfRPFFB Xm71AiB0nti9hid91s2fIfLKwJ3O0+oNQITdFNySRPOotvhY8zANBgkqhkiG9w0B AQsFAAOCAQEAPtDRakMTR0lZeP4YJ3VQ522q1MqIcjlyV9T2iAwCnagC/aH+gfj0 pUXeR2eoatKjJ3/vpyWPV49sSWW9vuKjyeRFQXXotVrQr1J5uqJpeJpTOpIl+8+3 xXTe1ArDC3Uxfqze55O8sQLyNsxLktZaWQ66GhJlGZMywWWwDr61NLzVeeMxnRtg q3mrzsvdm53i5mbvJED6mBkfzpL2DK7TG3IukeDA0mzzUrTFCtn0XlbZGvqtiP17 WlDyv45kGi2jM9B45xYEjtQcw58DpwG7pWwYmvjFYG570l0mHdan6pOSco5VC0Xi 30WAe+cMBj7xLHEzM4aMvtCzPL2stqA8Vw== -----END CERTIFICATE----- -----BEGIN CERTIFICATE----- MIIFFjCCAv6gAwIBAgIRAJErCErPDBinU/bWLiWnX1owDQYJKoZIhvcNAQELBQAw TzELMAkGA1UEBhMCVVMxKTAnBgNVBAoTIEludGVybmV0IFNlY3VyaXR5IFJlc2Vh cmNoIEdyb3VwMRUwEwYDVQQDEwxJU1JHIFJvb3QgWDEwHhcNMjAwOTA0MDAwMDAw WhcNMjUwOTE1MTYwMDAwWjAyMQswCQYDVQQGEwJVUzEWMBQGA1UEChMNTGV0J3Mg RW5jcnlwdDELMAkGA1UEAxMCUjMwggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEK AoIBAQC7AhUozPaglNMPEuyNVZLD+ILxmaZ6QoinXSaqtSu5xUyxr45r+XXIo9cP R5QUVTVXjJ6oojkZ9YI8QqlObvU7wy7bjcCwXPNZOOftz2nwWgsbvsCUJCWH+jdx sxPnHKzhm+/b5DtFUkWWqcFTzjTIUu61ru2P3mBw4qVUq7ZtDpelQDRrK9O8Zutm NHz6a4uPVymZ+DAXXbpyb/uBxa3Shlg9F8fnCbvxK/eG3MHacV3URuPMrSXBiLxg Z3Vms/EY96Jc5lP/Ooi2R6X/ExjqmAl3P51T+c8B5fWmcBcUr2Ok/5mzk53cU6cG /kiFHaFpriV1uxPMUgP17VGhi9sVAgMBAAGjggEIMIIBBDAOBgNVHQ8BAf8EBAMC AYYwHQYDVR0lBBYwFAYIKwYBBQUHAwIGCCsGAQUFBwMBMBIGA1UdEwEB/wQIMAYB Af8CAQAwHQYDVR0OBBYEFBQusxe3WFbLrlAJQOYfr52LFMLGMB8GA1UdIwQYMBaA FHm0WeZ7tuXkAXOACIjIGlj26ZtuMDIGCCsGAQUFBwEBBCYwJDAiBggrBgEFBQcw AoYWaHR0cDovL3gxLmkubGVuY3Iub3JnLzAnBgNVHR8EIDAeMBygGqAYhhZodHRw Oi8veDEuYy5sZW5jci5vcmcvMCIGA1UdIAQbMBkwCAYGZ4EMAQIBMA0GCysGAQQB gt8TAQEBMA0GCSqGSIb3DQEBCwUAA4ICAQCFyk5HPqP3hUSFvNVneLKYY611TR6W PTNlclQtgaDqw+34IL9fzLdwALduO/ZelN7kIJ+m74uyA+eitRY8kc607TkC53wl ikfmZW4/RvTZ8M6UK+5UzhK8jCdLuMGYL6KvzXGRSgi3yLgjewQtCPkIVz6D2QQz CkcheAmCJ8MqyJu5zlzyZMjAvnnAT45tRAxekrsu94sQ4egdRCnbWSDtY7kh+BIm lJNXoB1lBMEKIq4QDUOXoRgffuDghje1WrG9ML+Hbisq/yFOGwXD9RiX8F6sw6W4 avAuvDszue5L3sz85K+EC4Y/wFVDNvZo4TYXao6Z0f+lQKc0t8DQYzk1OXVu8rp2 yJMC6alLbBfODALZvYH7n7do1AZls4I9d1P4jnkDrQoxB3UqQ9hVl3LEKQ73xF1O yK5GhDDX8oVfGKF5u+decIsH4YaTw7mP3GFxJSqv3+0lUFJoi5Lc5da149p90Ids hCExroL1+7mryIkXPeFM5TgO9r0rvZaBFOvV2z0gp35Z0+L4WPlbuEjN/lxPFin+ HlUjr8gRsI3qfJOQFy/9rKIJR0Y/8Omwt/8oTWgy1mdeHmmjk7j1nYsvC9JSQ6Zv MldlTTKB3zhThV1+XWYp6rjd5JW1zbVWEkLNxE7GJThEUG3szgBVGP7pSWTUTsqX nLRbwHOoq7hHwg== -----END CERTIFICATE-----
$ split -d -p "BEGIN CERTIFICATE" ssl.crt pem- $ ls pem-* pem-00 pem-01 $ openssl x509 -in pem-00 -serial -dates -issuer -subject -noout serial=043413178B643A5D71384163C18573BEDA46 notBefore=Aug 2 00:25:52 2023 GMT notAfter=Oct 31 00:25:51 2023 GMT issuer=C = US, O = Let's Encrypt, CN = R3 subject=CN = kyanny-1690939049.qaboot.net $ openssl x509 -in pem-01 -serial -dates -issuer -subject -noout serial=912B084ACF0C18A753F6D62E25A75F5A notBefore=Sep 4 00:00:00 2020 GMT notAfter=Sep 15 16:00:00 2025 GMT issuer=C = US, O = Internet Security Research Group, CN = ISRG Root X1 subject=C = US, O = Let's Encrypt, CN = R3
