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Diffstat (limited to 'net/sunrpc/auth_gss/gss_krb5_unseal.c')
-rw-r--r--net/sunrpc/auth_gss/gss_krb5_unseal.c202
1 files changed, 202 insertions, 0 deletions
diff --git a/net/sunrpc/auth_gss/gss_krb5_unseal.c b/net/sunrpc/auth_gss/gss_krb5_unseal.c
new file mode 100644
index 00000000000..8767fc53183
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+++ b/net/sunrpc/auth_gss/gss_krb5_unseal.c
@@ -0,0 +1,202 @@
+/*
+ * linux/net/sunrpc/gss_krb5_unseal.c
+ *
+ * Adapted from MIT Kerberos 5-1.2.1 lib/gssapi/krb5/k5unseal.c
+ *
+ * Copyright (c) 2000 The Regents of the University of Michigan.
+ * All rights reserved.
+ *
+ * Andy Adamson <andros@umich.edu>
+ */
+
+/*
+ * Copyright 1993 by OpenVision Technologies, Inc.
+ *
+ * Permission to use, copy, modify, distribute, and sell this software
+ * and its documentation for any purpose is hereby granted without fee,
+ * provided that the above copyright notice appears in all copies and
+ * that both that copyright notice and this permission notice appear in
+ * supporting documentation, and that the name of OpenVision not be used
+ * in advertising or publicity pertaining to distribution of the software
+ * without specific, written prior permission. OpenVision makes no
+ * representations about the suitability of this software for any
+ * purpose. It is provided "as is" without express or implied warranty.
+ *
+ * OPENVISION DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL OPENVISION BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
+ * USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+ * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * Copyright (C) 1998 by the FundsXpress, INC.
+ *
+ * All rights reserved.
+ *
+ * Export of this software from the United States of America may require
+ * a specific license from the United States Government. It is the
+ * responsibility of any person or organization contemplating export to
+ * obtain such a license before exporting.
+ *
+ * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
+ * distribute this software and its documentation for any purpose and
+ * without fee is hereby granted, provided that the above copyright
+ * notice appear in all copies and that both that copyright notice and
+ * this permission notice appear in supporting documentation, and that
+ * the name of FundsXpress. not be used in advertising or publicity pertaining
+ * to distribution of the software without specific, written prior
+ * permission. FundsXpress makes no representations about the suitability of
+ * this software for any purpose. It is provided "as is" without express
+ * or implied warranty.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/sunrpc/gss_krb5.h>
+#include <linux/crypto.h>
+
+#ifdef RPC_DEBUG
+# define RPCDBG_FACILITY RPCDBG_AUTH
+#endif
+
+
+/* message_buffer is an input if toktype is MIC and an output if it is WRAP:
+ * If toktype is MIC: read_token is a mic token, and message_buffer is the
+ * data that the mic was supposedly taken over.
+ * If toktype is WRAP: read_token is a wrap token, and message_buffer is used
+ * to return the decrypted data.
+ */
+
+/* XXX will need to change prototype and/or just split into a separate function
+ * when we add privacy (because read_token will be in pages too). */
+u32
+krb5_read_token(struct krb5_ctx *ctx,
+ struct xdr_netobj *read_token,
+ struct xdr_buf *message_buffer,
+ int *qop_state, int toktype)
+{
+ int signalg;
+ int sealalg;
+ s32 checksum_type;
+ struct xdr_netobj md5cksum = {.len = 0, .data = NULL};
+ s32 now;
+ int direction;
+ s32 seqnum;
+ unsigned char *ptr = (unsigned char *)read_token->data;
+ int bodysize;
+ u32 ret = GSS_S_DEFECTIVE_TOKEN;
+
+ dprintk("RPC: krb5_read_token\n");
+
+ if (g_verify_token_header(&ctx->mech_used, &bodysize, &ptr,
+ read_token->len))
+ goto out;
+
+ if ((*ptr++ != ((toktype>>8)&0xff)) || (*ptr++ != (toktype&0xff)))
+ goto out;
+
+ /* XXX sanity-check bodysize?? */
+
+ if (toktype == KG_TOK_WRAP_MSG) {
+ /* XXX gone */
+ goto out;
+ }
+
+ /* get the sign and seal algorithms */
+
+ signalg = ptr[0] + (ptr[1] << 8);
+ sealalg = ptr[2] + (ptr[3] << 8);
+
+ /* Sanity checks */
+
+ if ((ptr[4] != 0xff) || (ptr[5] != 0xff))
+ goto out;
+
+ if (((toktype != KG_TOK_WRAP_MSG) && (sealalg != 0xffff)) ||
+ ((toktype == KG_TOK_WRAP_MSG) && (sealalg == 0xffff)))
+ goto out;
+
+ /* in the current spec, there is only one valid seal algorithm per
+ key type, so a simple comparison is ok */
+
+ if ((toktype == KG_TOK_WRAP_MSG) && !(sealalg == ctx->sealalg))
+ goto out;
+
+ /* there are several mappings of seal algorithms to sign algorithms,
+ but few enough that we can try them all. */
+
+ if ((ctx->sealalg == SEAL_ALG_NONE && signalg > 1) ||
+ (ctx->sealalg == SEAL_ALG_1 && signalg != SGN_ALG_3) ||
+ (ctx->sealalg == SEAL_ALG_DES3KD &&
+ signalg != SGN_ALG_HMAC_SHA1_DES3_KD))
+ goto out;
+
+ /* compute the checksum of the message */
+
+ /* initialize the the cksum */
+ switch (signalg) {
+ case SGN_ALG_DES_MAC_MD5:
+ checksum_type = CKSUMTYPE_RSA_MD5;
+ break;
+ default:
+ ret = GSS_S_DEFECTIVE_TOKEN;
+ goto out;
+ }
+
+ switch (signalg) {
+ case SGN_ALG_DES_MAC_MD5:
+ ret = make_checksum(checksum_type, ptr - 2, 8,
+ message_buffer, &md5cksum);
+ if (ret)
+ goto out;
+
+ ret = krb5_encrypt(ctx->seq, NULL, md5cksum.data,
+ md5cksum.data, 16);
+ if (ret)
+ goto out;
+
+ if (memcmp(md5cksum.data + 8, ptr + 14, 8)) {
+ ret = GSS_S_BAD_SIG;
+ goto out;
+ }
+ break;
+ default:
+ ret = GSS_S_DEFECTIVE_TOKEN;
+ goto out;
+ }
+
+ /* it got through unscathed. Make sure the context is unexpired */
+
+ if (qop_state)
+ *qop_state = GSS_C_QOP_DEFAULT;
+
+ now = get_seconds();
+
+ ret = GSS_S_CONTEXT_EXPIRED;
+ if (now > ctx->endtime)
+ goto out;
+
+ /* do sequencing checks */
+
+ ret = GSS_S_BAD_SIG;
+ if ((ret = krb5_get_seq_num(ctx->seq, ptr + 14, ptr + 6, &direction,
+ &seqnum)))
+ goto out;
+
+ if ((ctx->initiate && direction != 0xff) ||
+ (!ctx->initiate && direction != 0))
+ goto out;
+
+ ret = GSS_S_COMPLETE;
+out:
+ if (md5cksum.data) kfree(md5cksum.data);
+ return ret;
+}