SUNRPC: Support the Camellia enctypes

RFC 6803 defines two encryption types that use Camellia ciphers (RFC
3713) and CMAC digests. Implement support for those in SunRPC's GSS
Kerberos 5 mechanism.

There has not been an explicit request to support these enctypes.
However, this new set of enctypes provides a good alternative to the
AES-SHA1 enctypes that are to be deprecated at some point.

As this implementation is still a "beta", the default is to not
build it automatically.
Tested-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

include/linux/sunrpc/gss_krb5.h

@@ -176,6 +176,8 @@ enum seal_alg {
 #define CKSUMTYPE_HMAC_SHA1_DES3	0x000c
 #define CKSUMTYPE_HMAC_SHA1_96_AES128   0x000f
 #define CKSUMTYPE_HMAC_SHA1_96_AES256   0x0010
+#define CKSUMTYPE_CMAC_CAMELLIA128	0x0011
+#define CKSUMTYPE_CMAC_CAMELLIA256	0x0012
 #define CKSUMTYPE_HMAC_SHA256_128_AES128	0x0013
 #define CKSUMTYPE_HMAC_SHA384_192_AES256	0x0014
 #define CKSUMTYPE_HMAC_MD5_ARCFOUR      -138 /* Microsoft md5 hmac cksumtype */
@@ -220,6 +222,8 @@ enum seal_alg {
 #define ENCTYPE_AES256_CTS_HMAC_SHA384_192	0x0014
 #define ENCTYPE_ARCFOUR_HMAC            0x0017
 #define ENCTYPE_ARCFOUR_HMAC_EXP        0x0018
+#define ENCTYPE_CAMELLIA128_CTS_CMAC	0x0019
+#define ENCTYPE_CAMELLIA256_CTS_CMAC	0x001A
 #define ENCTYPE_UNKNOWN         0x01ff
 
 /*

net/sunrpc/Kconfig

@@ -80,6 +80,19 @@ config RPCSEC_GSS_KRB5_ENCTYPES_AES_SHA1
 	  SHA-1 digests. These include aes128-cts-hmac-sha1-96 and
 	  aes256-cts-hmac-sha1-96.
 
+config RPCSEC_GSS_KRB5_ENCTYPES_CAMELLIA
+	bool "Enable Kerberos encryption types based on Camellia and CMAC"
+	depends on RPCSEC_GSS_KRB5
+	depends on CRYPTO_CBC && CRYPTO_CTS && CRYPTO_CAMELLIA
+	depends on CRYPTO_CMAC
+	default n
+	select RPCSEC_GSS_KRB5_CRYPTOSYSTEM
+	help
+	  Choose Y to enable the use of Kerberos 5 encryption types
+	  that utilize Camellia ciphers (RFC 3713) and CMAC digests
+	  (NIST Special Publication 800-38B). These include
+	  camellia128-cts-cmac and camellia256-cts-cmac.
+
 config RPCSEC_GSS_KRB5_ENCTYPES_AES_SHA2
 	bool "Enable Kerberos enctypes based on AES and SHA-2"
 	depends on RPCSEC_GSS_KRB5

net/sunrpc/auth_gss/gss_krb5_mech.c

@@ -147,6 +147,61 @@ static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
 	},
 #endif
 
+#if defined(CONFIG_RPCSEC_GSS_KRB5_ENCTYPES_CAMELLIA)
+	/*
+	 * Camellia-128 with CMAC (RFC 6803)
+	 */
+	{
+		.etype		= ENCTYPE_CAMELLIA128_CTS_CMAC,
+		.ctype		= CKSUMTYPE_CMAC_CAMELLIA128,
+		.name		= "camellia128-cts-cmac",
+		.encrypt_name	= "cts(cbc(camellia))",
+		.aux_cipher	= "cbc(camellia)",
+		.cksum_name	= "cmac(camellia)",
+		.cksumlength	= BITS2OCTETS(128),
+		.keyed_cksum	= 1,
+		.keylength	= BITS2OCTETS(128),
+		.Kc_length	= BITS2OCTETS(128),
+		.Ke_length	= BITS2OCTETS(128),
+		.Ki_length	= BITS2OCTETS(128),
+
+		.import_ctx	= gss_krb5_import_ctx_v2,
+		.encrypt	= gss_krb5_aes_encrypt,
+		.decrypt	= gss_krb5_aes_decrypt,
+
+		.get_mic	= gss_krb5_get_mic_v2,
+		.verify_mic	= gss_krb5_verify_mic_v2,
+		.wrap		= gss_krb5_wrap_v2,
+		.unwrap		= gss_krb5_unwrap_v2,
+	},
+	/*
+	 * Camellia-256 with CMAC (RFC 6803)
+	 */
+	{
+		.etype		= ENCTYPE_CAMELLIA256_CTS_CMAC,
+		.ctype		= CKSUMTYPE_CMAC_CAMELLIA256,
+		.name		= "camellia256-cts-cmac",
+		.encrypt_name	= "cts(cbc(camellia))",
+		.aux_cipher	= "cbc(camellia)",
+		.cksum_name	= "cmac(camellia)",
+		.cksumlength	= BITS2OCTETS(128),
+		.keyed_cksum	= 1,
+		.keylength	= BITS2OCTETS(256),
+		.Kc_length	= BITS2OCTETS(256),
+		.Ke_length	= BITS2OCTETS(256),
+		.Ki_length	= BITS2OCTETS(256),
+
+		.import_ctx	= gss_krb5_import_ctx_v2,
+		.encrypt	= gss_krb5_aes_encrypt,
+		.decrypt	= gss_krb5_aes_decrypt,
+
+		.get_mic	= gss_krb5_get_mic_v2,
+		.verify_mic	= gss_krb5_verify_mic_v2,
+		.wrap		= gss_krb5_wrap_v2,
+		.unwrap		= gss_krb5_unwrap_v2,
+	},
+#endif
+
 #if defined(CONFIG_RPCSEC_GSS_KRB5_ENCTYPES_AES_SHA2)
 	/*
 	 * AES-128 with SHA-256 (RFC 8009)