add more tests

#[test]

#[cfg(ossl110)]

fn test_subject_key_id() {

    let cert = include_bytes!("../../test/github.pem");

    let cert = include_bytes!("../../test/certv3.pem");

    let cert = X509::from_pem(cert).unwrap();

    let subject_key_id = cert.subject_key_id().unwrap();

    assert_eq!(

        subject_key_id.as_slice(),

        &b"\xC7\x07\x27\x78\x85\xF2\x9D\x33\xC9\x4C\x5E\x56\x7D\x5C\xD6\x8E\x72\x67\xEB\xDE"[..]

        &b"\xB6\x73\x2F\x61\xA5\x4B\xA1\xEF\x48\x2C\x15\xB1\x9F\xF3\xDC\x34\x2F\xBC\xAC\x30"[..]

    );

}

#[test]

#[cfg(ossl110)]

fn test_authority_key_id() {

    let cert = include_bytes!("../../test/github.pem");

    let cert = include_bytes!("../../test/certv3.pem");

    let cert = X509::from_pem(cert).unwrap();

    let subject_key_id = cert.authority_key_id().unwrap();

    let authority_key_id = cert.authority_key_id().unwrap();

    assert_eq!(

        subject_key_id.as_slice(),

        &b"\x0A\xBC\x08\x29\x17\x8C\xA5\x39\x6D\x7A\x0E\xCE\x33\xC7\x2E\xB3\xED\xFB\xC3\x7A"[..]

        authority_key_id.as_slice(),

        &b"\x6C\xD3\xA5\x03\xAB\x0D\x5F\x2C\xC9\x8D\x8A\x9C\x88\xA7\x88\x77\xB8\x37\xFD\x9A"[..]

    );

}

#[test]

fn test_authority_issuer_and_serial() {

    let cert = include_bytes!("../../test/authority_key_identifier.pem");

    let cert = X509::from_pem(cert).unwrap();

    let authority_issuer = cert.authority_issuer().unwrap();

    assert_eq!(1, authority_issuer.len());

    let dn = authority_issuer[0].directory_name().unwrap();

    let mut o = dn.entries_by_nid(Nid::ORGANIZATIONNAME);

    let o = o.next().unwrap().data().as_utf8().unwrap();

    assert_eq!(o.as_bytes(), b"PyCA");

    let mut cn = dn.entries_by_nid(Nid::COMMONNAME);

    let cn = cn.next().unwrap().data().as_utf8().unwrap();

    assert_eq!(cn.as_bytes(), b"cryptography.io");

    let authority_serial = cert.authority_serial().unwrap();

    let serial = authority_serial.to_bn().unwrap();

    let expected = BigNum::from_u32(3).unwrap();

    assert_eq!(serial, expected);

}

#[test]

fn test_subject_alt_name_iter() {

    let cert = include_bytes!("../../test/alt_name_cert.pem");

-----BEGIN CERTIFICATE-----

MIIDIjCCAgqgAwIBAgIBAzANBgkqhkiG9w0BAQUFADApMQ0wCwYDVQQKDARQeUNB

MRgwFgYDVQQDDA9jcnlwdG9ncmFwaHkuaW8wHhcNMTUwNTAzMDk0OTU2WhcNMTYw

NTAyMDk0OTU2WjApMQ0wCwYDVQQKDARQeUNBMRgwFgYDVQQDDA9jcnlwdG9ncmFw

aHkuaW8wggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQDCadi1UZioxdnP

ajqlRZHeKsSxvXXhgrWvlt91P3gV0dBThRFhJsLOhjNLz6PO6KeRbjz9GhTA2hdk

xtIpXrjvTv9dEJ1/k0xebsHWgFC43aTlgekw0U4cMwMe5NGeeg1tfzbJwldIN+cK

vabc08ADlkmM6DMnUArkzA2yii0DErRFMSIGrkDr6E9puord3h6Mh8Jfnc3TDAq8

Qo1DI2XM7oFSWNfecQ9KbIC5wzzT+7Shoyz7QmCk/XhRzt8Xcfc3yAXIwazvLf8b

YP1auaSG11a5E+w6onj91h8UHKKOXu+rdq5YYPZ+qUYpxA7ZJ/VAGadMulYbXaO8

Syi39HTpAgMBAAGjVTBTMFEGA1UdIwRKMEiAFDlFPso9Yh3qhkn2WqtAt6RwmPHs

oS2kKzApMQ0wCwYDVQQKDARQeUNBMRgwFgYDVQQDDA9jcnlwdG9ncmFwaHkuaW+C

AQMwDQYJKoZIhvcNAQEFBQADggEBAFbZYy6aZJUK/f7nJx2Rs/ht6hMbM32/RoXZ

JGbYapNVqVu/vymcfc/se3FHS5OVmPsnRlo/FIKDn/r5DGl73Sn/FvDJiLJZFucT

msyYuHZ+ZRYWzWmN2fcB3cfxj0s3qps6f5OoCOqoINOSe4HRGlw4X9keZSD+3xAt

vHNwQdlPC7zWbPdrzLT+FqR0e/O81vFJJS6drHJWqPcR3NQVtZw+UF7A/HKwbfeL

Nu2zj6165hzOi9HUxa2/mPr/eLUUV1sTzXp2+TFjt3rVCjW1XnpMLdwNBHzjpyAB

dTOX3iw0+BPy3s2jtnCW1PLpc74kvSTaBwhg74sq39EXfIKax00=

-----END CERTIFICATE-----

-----BEGIN CERTIFICATE-----

MIIFajCCBPGgAwIBAgIQDNCovsYyz+ZF7KCpsIT7HDAKBggqhkjOPQQDAzBWMQsw

CQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMTAwLgYDVQQDEydEaWdp

Q2VydCBUTFMgSHlicmlkIEVDQyBTSEEzODQgMjAyMCBDQTEwHhcNMjMwMjE0MDAw

MDAwWhcNMjQwMzE0MjM1OTU5WjBmMQswCQYDVQQGEwJVUzETMBEGA1UECBMKQ2Fs

aWZvcm5pYTEWMBQGA1UEBxMNU2FuIEZyYW5jaXNjbzEVMBMGA1UEChMMR2l0SHVi

LCBJbmMuMRMwEQYDVQQDEwpnaXRodWIuY29tMFkwEwYHKoZIzj0CAQYIKoZIzj0D

AQcDQgAEo6QDRgPfRlFWy8k5qyLN52xZlnqToPu5QByQMog2xgl2nFD1Vfd2Xmgg

nO4i7YMMFTAQQUReMqyQodWq8uVDs6OCA48wggOLMB8GA1UdIwQYMBaAFAq8CCkX

jKU5bXoOzjPHLrPt+8N6MB0GA1UdDgQWBBTHByd4hfKdM8lMXlZ9XNaOcmfr3jAl

BgNVHREEHjAcggpnaXRodWIuY29tgg53d3cuZ2l0aHViLmNvbTAOBgNVHQ8BAf8E

BAMCB4AwHQYDVR0lBBYwFAYIKwYBBQUHAwEGCCsGAQUFBwMCMIGbBgNVHR8EgZMw

gZAwRqBEoEKGQGh0dHA6Ly9jcmwzLmRpZ2ljZXJ0LmNvbS9EaWdpQ2VydFRMU0h5

YnJpZEVDQ1NIQTM4NDIwMjBDQTEtMS5jcmwwRqBEoEKGQGh0dHA6Ly9jcmw0LmRp

Z2ljZXJ0LmNvbS9EaWdpQ2VydFRMU0h5YnJpZEVDQ1NIQTM4NDIwMjBDQTEtMS5j

cmwwPgYDVR0gBDcwNTAzBgZngQwBAgIwKTAnBggrBgEFBQcCARYbaHR0cDovL3d3

dy5kaWdpY2VydC5jb20vQ1BTMIGFBggrBgEFBQcBAQR5MHcwJAYIKwYBBQUHMAGG

GGh0dHA6Ly9vY3NwLmRpZ2ljZXJ0LmNvbTBPBggrBgEFBQcwAoZDaHR0cDovL2Nh

Y2VydHMuZGlnaWNlcnQuY29tL0RpZ2lDZXJ0VExTSHlicmlkRUNDU0hBMzg0MjAy

MENBMS0xLmNydDAJBgNVHRMEAjAAMIIBgAYKKwYBBAHWeQIEAgSCAXAEggFsAWoA

dwDuzdBk1dsazsVct520zROiModGfLzs3sNRSFlGcR+1mwAAAYZQ3Rv6AAAEAwBI

MEYCIQDkFq7T4iy6gp+pefJLxpRS7U3gh8xQymmxtI8FdzqU6wIhALWfw/nLD63Q

YPIwG3EFchINvWUfB6mcU0t2lRIEpr8uAHYASLDja9qmRzQP5WoC+p0w6xxSActW

3SyB2bu/qznYhHMAAAGGUN0cKwAABAMARzBFAiAePGAyfiBR9dbhr31N9ZfESC5G

V2uGBTcyTyUENrH3twIhAPwJfsB8A4MmNr2nW+sdE1n2YiCObW+3DTHr2/UR7lvU

AHcAO1N3dT4tuYBOizBbBv5AO2fYT8P0x70ADS1yb+H61BcAAAGGUN0cOgAABAMA

SDBGAiEAzOBr9OZ0+6OSZyFTiywN64PysN0FLeLRyL5jmEsYrDYCIQDu0jtgWiMI

KU6CM0dKcqUWLkaFE23c2iWAhYAHqrFRRzAKBggqhkjOPQQDAwNnADBkAjAE3A3U

3jSZCpwfqOHBdlxi9ASgKTU+wg0qw3FqtfQ31OwLYFdxh0MlNk/HwkjRSWgCMFbQ

vMkXEPvNvv4t30K6xtpG26qmZ+6OiISBIIXMljWnsiYR1gyZnTzIg3AQSw4Vmw==

-----END CERTIFICATE-----