Getting server certificates with openssl

This recipe is very useful if you need to download the certificate from a server that uses ssl for connection encryption.

With your favorite openssl distribution just type:

openssl s_client -connect 172.16.1.42:22

CONNECTED(00000003)

depth=0 /C=ES/ST=Spain/L=madrid/O=xxx/OU=seguridad/CN=localhost

verify error:num=18:self signed certificate

verify return:1

depth=0 /C=ES/ST=Spain/L=madrid/O=xxx/OU=seguridad/CN=localhost

verify return:1

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Certificate chain

0 s:/C=ES/ST=Spain/L=madrid/O=xxx/OU=seguridad/CN=localhost

i:/C=ES/ST=Spain/L=madrid/O=xxx/OU=seguridad/CN=localhost

---

Server certificate

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

MIIC/DCCAroCBEuLj7EwCwYHKoZIzjgEAwUAMGQxCzAJBgNVBAYTAkVTMQ4wDAYD

VQQIEwVTcGFpbjEPMA0GA1UEBxMGbWFkcmlkMQwwCgYDVQQKEwNzaWExEjAQBgNV

BAsTCXNlZ3VyaWRhZDESMBAGA1UEAxMJbG9jYWxob3N0MB4XDTEwMDMwMTA5NTgw

OVoXDTEwMDUzMDA5NTgwOVowZDELMAkGA1UEBhMCRVMxDjAMBgNVBAgTBVNwYWlu

MQ8wDQYDVQQHEwZtYWRyaWQxDDAKBgNVBAoTA3NpYTESMBAGA1UECxMJc2VndXJp

ZGFkMRIwEAYDVQQDEwlsb2NhbGhvc3QwggG3MIIBLAYHKoZIzjgEATCCAR8CgYEA

/X9TgR11EilS30qcLuzk5/YRt1I870QAwx4/gLZRJmlFXUAiUftZPY1Y+r/F9bow

9subVWzXgTuAHTRv8mZgt2uZUKWkn5/oBHsQIsJPu6nX/rfGG/g7V+fGqKYVDwT7

g/bTxR7DAjVUE1oWkTL2dfOuK2HXKu/yIgMZndFIAccCFQCXYFCPFSMLzLKSuYKi

64QL8Fgc9QKBgQD34aCF1ps93su8q1w2uFe5eZSvu/o66oL5V0wLPQeCZ1FZV466

1FlP5nEHEIGAtEkWcSPoTCgWE7fPCTKMyKbhPBZ6i1R8jSjgo64eK7OmdZFuo38L

+iE1YvH7YnoBJDvMpPG+qFGQiaiD3+Fa5Z8GkotmXoB7VSVkAUw7/s9JKgOBhAAC

gYB6L1euyIcyqIcnDqjNoVxTIbq+hXPGuV7E27j6PkXQdhboJJPvOrBnS7GbCMtP

65IbedsJm+raK5rfCzkUXvrg6/LNM9zs6BNBZBVLiyh2o2ueecGc6hBCUA2WMbGc

6QB3oBIfxAv++//1+knIL1+A26jrBU58AfnNpDK43T1coTALBgcqhkjOOAQDBQAD

LwAwLAIURZdToJ9MjzXze0oCgS280KwsunICFC1Crf4hj1kP7OdZhVXvlP4gCQi1

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

subject=/C=ES/ST=Spain/L=madrid/O=xxx/OU=seguridad/CN=localhost

issuer=/C=ES/ST=Spain/L=madrid/O=xxx/OU=seguridad/CN=localhost

---

Acceptable client certificate CA names

/C=ES/O=Recipes/CN=ca

---

SSL handshake has read 1315 bytes and written 288 bytes

---

New, TLSv1/SSLv3, Cipher is EDH-DSS-DES-CBC3-SHA

Server public key is 1024 bit

Compression: NONE

Expansion: NONE

SSL-Session:

Protocol : TLSv1

Cipher : EDH-DSS-DES-CBC3-SHA

Session-ID: 4B976688585F4BDA3C35765B4F2C6119F90064A77BFCC73D4C2E26A283864204

Session-ID-ctx:

Master-Key: D0D069F3AC2059DA628F55A2847A7EA9744AADBB62FA379D1D480832FB36330A560D93872F75CA340C999733EB0E2F45

Key-Arg : None

Start Time: 1268213384

Timeout : 300 (sec)

Verify return code: 18 (self signed certificate)

---

closed