gss_krb5: add support for triple-des encryption

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

Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

6 files changed, 83 insertions, 0 deletions

diff --git a/net/sunrpc/auth_gss/gss_krb5_crypto.c b/net/sunrpc/auth_gss/gss_krb5_crypto.c
index cae04d7a45a5..bb76873aa019 100644
--- a/net/sunrpc/auth_gss/gss_krb5_crypto.c
+++ b/net/sunrpc/auth_gss/gss_krb5_crypto.c
@@ -184,6 +184,9 @@ 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 253b4149584a..d54668790f0c 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(const 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 03f1dcddbd29..7cebdf843266 100644
--- a/net/sunrpc/auth_gss/gss_krb5_mech.c
+++ b/net/sunrpc/auth_gss/gss_krb5_mech.c
@@ -71,6 +71,26 @@ static const 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 const int num_supported_enctypes =
@@ -440,6 +460,9 @@ 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) {
                 dprintk("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 cd512719092b..7ede900049a7 100644
--- a/net/sunrpc/auth_gss/gss_krb5_seal.c
+++ b/net/sunrpc/auth_gss/gss_krb5_seal.c
@@ -142,6 +142,7 @@ 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 7515bffddf15..3e15bdb5a9eb 100644
--- a/net/sunrpc/auth_gss/gss_krb5_unseal.c
+++ b/net/sunrpc/auth_gss/gss_krb5_unseal.c
@@ -152,6 +152,7 @@ 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 2eb3046a84ea..1c8ebd3dbd3c 100644
--- a/net/sunrpc/auth_gss/gss_krb5_wrap.c
+++ b/net/sunrpc/auth_gss/gss_krb5_wrap.c
@@ -350,6 +350,7 @@ 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);
         }
 }
@@ -363,6 +364,7 @@ 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);
         }
 }