2008-04-30 16:47:00

by Kevin Coffman

[permalink] [raw]
Subject: [enctypes round 2: PATCH 14/26] gss_krb5: add support for triple-des encryption

Add the final pieces to support the triple-des encryption type.

Signed-off-by: Kevin Coffman <[email protected]>
---

fs/Kconfig | 2 +
include/linux/sunrpc/gss_krb5.h | 5 +++
net/sunrpc/auth_gss/gss_krb5_crypto.c | 3 ++
net/sunrpc/auth_gss/gss_krb5_keys.c | 53 +++++++++++++++++++++++++++++++++
net/sunrpc/auth_gss/gss_krb5_mech.c | 23 ++++++++++++++
net/sunrpc/auth_gss/gss_krb5_seal.c | 1 +
net/sunrpc/auth_gss/gss_krb5_unseal.c | 1 +
net/sunrpc/auth_gss/gss_krb5_wrap.c | 2 +
8 files changed, 90 insertions(+), 0 deletions(-)

diff --git a/fs/Kconfig b/fs/Kconfig
index 2e43d46..257939b 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -1828,6 +1828,8 @@ config RPCSEC_GSS_KRB5
select CRYPTO_MD5
select CRYPTO_DES
select CRYPTO_CBC
+ select CRYPTO_HMAC
+ select CRYPTO_SHA1
help
Choose Y here to enable Secure RPC using the Kerberos version 5
GSS-API mechanism (RFC 1964).
diff --git a/include/linux/sunrpc/gss_krb5.h b/include/linux/sunrpc/gss_krb5.h
index 70241c9..a76255d 100644
--- a/include/linux/sunrpc/gss_krb5.h
+++ b/include/linux/sunrpc/gss_krb5.h
@@ -263,3 +263,8 @@ krb5_derive_key(struct gss_krb5_enctype *gk5e,
const struct xdr_netobj *inkey,
struct xdr_netobj *outkey,
const struct xdr_netobj *in_constant);
+
+u32
+gss_krb5_des3_make_key(struct gss_krb5_enctype *gk5e,
+ struct xdr_netobj *randombits,
+ struct xdr_netobj *key);
diff --git a/net/sunrpc/auth_gss/gss_krb5_crypto.c b/net/sunrpc/auth_gss/gss_krb5_crypto.c
index 389f366..0c91186 100644
--- a/net/sunrpc/auth_gss/gss_krb5_crypto.c
+++ b/net/sunrpc/auth_gss/gss_krb5_crypto.c
@@ -185,6 +185,9 @@ make_checksum(struct krb5_ctx *kctx, char *header, int hdrlen,
checksumdata + checksumlen - kctx->gk5e->cksumlength,
kctx->gk5e->cksumlength);
break;
+ case CKSUMTYPE_HMAC_SHA1_DES3:
+ memcpy(cksumout->data, checksumdata, kctx->gk5e->cksumlength);
+ break;
default:
BUG();
break;
diff --git a/net/sunrpc/auth_gss/gss_krb5_keys.c b/net/sunrpc/auth_gss/gss_krb5_keys.c
index 832ce90..29c4bc5 100644
--- a/net/sunrpc/auth_gss/gss_krb5_keys.c
+++ b/net/sunrpc/auth_gss/gss_krb5_keys.c
@@ -250,3 +250,56 @@ err_free_cipher:
err_return:
return ret;
}
+
+#define smask(step) ((1<<step)-1)
+#define pstep(x, step) (((x)&smask(step))^(((x)>>step)&smask(step)))
+#define parity_char(x) pstep(pstep(pstep((x), 4), 2), 1)
+
+static void mit_des_fixup_key_parity(u8 key[8])
+{
+ int i;
+ for (i = 0; i < 8; i++) {
+ key[i] &= 0xfe;
+ key[i] |= 1^parity_char(key[i]);
+ }
+}
+
+/*
+ * This is the des3 key derivation postprocess function
+ */
+u32 gss_krb5_des3_make_key(struct gss_krb5_enctype *gk5e,
+ struct xdr_netobj *randombits,
+ struct xdr_netobj *key)
+{
+ int i;
+ u32 ret = EINVAL;
+
+ if (key->len != 24) {
+ dprintk("%s: key->len is %d\n", __func__, key->len);
+ goto err_out;
+ }
+ if (randombits->len != 21) {
+ dprintk("%s: randombits->len is %d\n",
+ __func__, randombits->len);
+ goto err_out;
+ }
+
+ /* take the seven bytes, move them around into the top 7 bits of the
+ 8 key bytes, then compute the parity bits. Do this three times. */
+
+ for (i = 0; i < 3; i++) {
+ memcpy(key->data + i*8, randombits->data + i*7, 7);
+ key->data[i*8+7] = (((key->data[i*8]&1)<<1) |
+ ((key->data[i*8+1]&1)<<2) |
+ ((key->data[i*8+2]&1)<<3) |
+ ((key->data[i*8+3]&1)<<4) |
+ ((key->data[i*8+4]&1)<<5) |
+ ((key->data[i*8+5]&1)<<6) |
+ ((key->data[i*8+6]&1)<<7));
+
+ mit_des_fixup_key_parity(key->data + i*8);
+ }
+ ret = 0;
+err_out:
+ return(ret);
+}
diff --git a/net/sunrpc/auth_gss/gss_krb5_mech.c b/net/sunrpc/auth_gss/gss_krb5_mech.c
index f5935fa..cef534d 100644
--- a/net/sunrpc/auth_gss/gss_krb5_mech.c
+++ b/net/sunrpc/auth_gss/gss_krb5_mech.c
@@ -69,6 +69,26 @@ static struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
.cksumlength = 8,
.keyed_cksum = 0,
},
+ /*
+ * 3DES
+ */
+ {
+ .etype = ENCTYPE_DES3_CBC_RAW,
+ .ctype = CKSUMTYPE_HMAC_SHA1_DES3,
+ .name = "des3-hmac-sha1",
+ .encrypt_name = "cbc(des3_ede)",
+ .cksum_name = "hmac(sha1)",
+ .encrypt = krb5_encrypt,
+ .decrypt = krb5_decrypt,
+ .mk_key = gss_krb5_des3_make_key,
+ .signalg = SGN_ALG_HMAC_SHA1_DES3_KD,
+ .sealalg = SEAL_ALG_DES3KD,
+ .keybytes = 21,
+ .keylength = 24,
+ .blocksize = 8,
+ .cksumlength = 20,
+ .keyed_cksum = 1,
+ },
};

static int num_supported_enctypes = ARRAY_SIZE(supported_gss_krb5_enctypes);
@@ -437,6 +457,9 @@ gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx)
p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));
if (IS_ERR(p))
goto out_err;
+ /* Map ENCTYPE_DES3_CBC_SHA1 to ENCTYPE_DES3_CBC_RAW */
+ if (ctx->enctype == ENCTYPE_DES3_CBC_SHA1)
+ ctx->enctype = ENCTYPE_DES3_CBC_RAW;
ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
if (ctx->gk5e == NULL) {
printk("gss_kerberos_mech: unsupported krb5 enctype %u\n",
diff --git a/net/sunrpc/auth_gss/gss_krb5_seal.c b/net/sunrpc/auth_gss/gss_krb5_seal.c
index 58563be..432d6e5 100644
--- a/net/sunrpc/auth_gss/gss_krb5_seal.c
+++ b/net/sunrpc/auth_gss/gss_krb5_seal.c
@@ -143,6 +143,7 @@ gss_get_mic_kerberos(struct gss_ctx *gss_ctx, struct xdr_buf *text,
default:
BUG();
case ENCTYPE_DES_CBC_RAW:
+ case ENCTYPE_DES3_CBC_RAW:
return gss_get_mic_v1(ctx, text, token);
}
}
diff --git a/net/sunrpc/auth_gss/gss_krb5_unseal.c b/net/sunrpc/auth_gss/gss_krb5_unseal.c
index d405943..404edbb 100644
--- a/net/sunrpc/auth_gss/gss_krb5_unseal.c
+++ b/net/sunrpc/auth_gss/gss_krb5_unseal.c
@@ -153,6 +153,7 @@ gss_verify_mic_kerberos(struct gss_ctx *gss_ctx,
default:
BUG();
case ENCTYPE_DES_CBC_RAW:
+ case ENCTYPE_DES3_CBC_RAW:
return gss_verify_mic_v1(ctx, message_buffer, read_token);
}
}
diff --git a/net/sunrpc/auth_gss/gss_krb5_wrap.c b/net/sunrpc/auth_gss/gss_krb5_wrap.c
index 2e4ab81..c9c8cfb 100644
--- a/net/sunrpc/auth_gss/gss_krb5_wrap.c
+++ b/net/sunrpc/auth_gss/gss_krb5_wrap.c
@@ -352,6 +352,7 @@ gss_wrap_kerberos(struct gss_ctx *gctx, int offset,
default:
BUG();
case ENCTYPE_DES_CBC_RAW:
+ case ENCTYPE_DES3_CBC_RAW:
return gss_wrap_kerberos_v1(kctx, offset, buf, pages);
}
}
@@ -365,6 +366,7 @@ gss_unwrap_kerberos(struct gss_ctx *gctx, int offset, struct xdr_buf *buf)
default:
BUG();
case ENCTYPE_DES_CBC_RAW:
+ case ENCTYPE_DES3_CBC_RAW:
return gss_unwrap_kerberos_v1(kctx, offset, buf);
}
}