Forum Discussion
SHA2 / SHA256 certificates
I have a customer that wants to use SHA2 / SHA256 certificates on their website (fronted by LTM), however clients such as Windows XP SP2 are unable to verify such certificates. The customer would lik...
Hi Kurt, I appreciate the reply, but unfortunately I don't think either option will work. I've done a bit more investigation since my first post - and to confirm my thoughts, I ran a quick (successful) test to an SSL site with SHA2 cert... the Client Hello contains the following Cipher Suites (36 suites) presented by my browser:
Cipher Suite: TLS_EMPTY_RENEGOTIATION_INFO_SCSV (0x00ff)
Cipher Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA (0xc00a)
Cipher Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA (0xc014)
Cipher Suite: TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA (0x0088)
Cipher Suite: TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA (0x0087)
Cipher Suite: TLS_DHE_DSS_WITH_AES_256_CBC_SHA (0x0038)
Cipher Suite: TLS_ECDH_RSA_WITH_AES_256_CBC_SHA (0xc00f)
Cipher Suite: TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA (0xc005)
Cipher Suite: TLS_RSA_WITH_CAMELLIA_256_CBC_SHA (0x0084)
Cipher Suite: TLS_RSA_WITH_AES_256_CBC_SHA (0x0035)
Cipher Suite: TLS_DHE_RSA_WITH_AES_256_CBC_SHA (0x0039)
Cipher Suite: TLS_ECDHE_ECDSA_WITH_RC4_128_SHA (0xc007)
Cipher Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA (0xc009)
Cipher Suite: TLS_ECDHE_RSA_WITH_RC4_128_SHA (0xc011)
Cipher Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA (0xc013)
Cipher Suite: TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA (0x0045)
Cipher Suite: TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA (0x0044)
Cipher Suite: TLS_DHE_RSA_WITH_AES_128_CBC_SHA (0x0033)
Cipher Suite: TLS_DHE_DSS_WITH_AES_128_CBC_SHA (0x0032)
Cipher Suite: TLS_ECDH_RSA_WITH_RC4_128_SHA (0xc00c)
Cipher Suite: TLS_ECDH_RSA_WITH_AES_128_CBC_SHA (0xc00e)
Cipher Suite: TLS_ECDH_ECDSA_WITH_RC4_128_SHA (0xc002)
Cipher Suite: TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA (0xc004)
Cipher Suite: TLS_RSA_WITH_SEED_CBC_SHA (0x0096)
Cipher Suite: TLS_RSA_WITH_CAMELLIA_128_CBC_SHA (0x0041)
Cipher Suite: TLS_RSA_WITH_RC4_128_MD5 (0x0004)
Cipher Suite: TLS_RSA_WITH_RC4_128_SHA (0x0005)
Cipher Suite: TLS_RSA_WITH_AES_128_CBC_SHA (0x002f)
Cipher Suite: TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA (0xc008)
Cipher Suite: TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA (0xc012)
Cipher Suite: TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA (0x0016)
Cipher Suite: TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA (0x0013)
Cipher Suite: TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA (0xc00d)
Cipher Suite: TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA (0xc003)
Cipher Suite: SSL_RSA_FIPS_WITH_3DES_EDE_CBC_SHA (0xfeff)
Cipher Suite: TLS_RSA_WITH_3DES_EDE_CBC_SHA (0x000a)
...as you can see, SHA2 is not listed. The Server Hello then shows the selected suite:
Cipher Suite: TLS_RSA_WITH_AES_256_CBC_SHA (0x0035)
... the certificate sent by the server shows the following information:
Certificates Length: 3714
Certificates (3714 bytes)
Certificate Length: 2083
Certificate (id-at-commonName=*detail removed*)
signedCertificate
algorithmIdentifier (sha256WithRSAEncryption)
Algorithm Id: 1.2.840.113549.1.1.11 (sha256WithRSAEncryption)
Padding: 0
encrypted: 54f056b0f5ec7b2a15d6e756c058d3df65d22cfaf8ed4e20...
Certificate Length: 1625
Certificate (id-at-commonName=*detail removed*)
signedCertificate
algorithmIdentifier (shaWithRSAEncryption)
Algorithm Id: 1.2.840.113549.1.1.5 (shaWithRSAEncryption)
Padding: 0
encrypted: 5d4f84f1a888d3a3b2bc9c6de5294977e1e7d6dca9d835ae...
You can see that the algorithmIdentifier is sha256WithRSAEncryption. So, in summary, my browser/OS was able to verify the SHA256 cert, but did not present any cipher suites with SHA256 included.
I guess this means that LTM SSL profiles plays no part in the certificate verification process, has no view of it, and therefore this problem can not be solved.
I hope I'm wrong :)