1 /* 2 * linux/net/sunrpc/gss_krb5_seal.c 3 * 4 * Adapted from MIT Kerberos 5-1.2.1 lib/gssapi/krb5/k5seal.c 5 * 6 * Copyright (c) 2000-2008 The Regents of the University of Michigan. 7 * All rights reserved. 8 * 9 * Andy Adamson <andros@umich.edu> 10 * J. Bruce Fields <bfields@umich.edu> 11 */ 12 13 /* 14 * Copyright 1993 by OpenVision Technologies, Inc. 15 * 16 * Permission to use, copy, modify, distribute, and sell this software 17 * and its documentation for any purpose is hereby granted without fee, 18 * provided that the above copyright notice appears in all copies and 19 * that both that copyright notice and this permission notice appear in 20 * supporting documentation, and that the name of OpenVision not be used 21 * in advertising or publicity pertaining to distribution of the software 22 * without specific, written prior permission. OpenVision makes no 23 * representations about the suitability of this software for any 24 * purpose. It is provided "as is" without express or implied warranty. 25 * 26 * OPENVISION DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 27 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO 28 * EVENT SHALL OPENVISION BE LIABLE FOR ANY SPECIAL, INDIRECT OR 29 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF 30 * USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR 31 * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 32 * PERFORMANCE OF THIS SOFTWARE. 33 */ 34 35 /* 36 * Copyright (C) 1998 by the FundsXpress, INC. 37 * 38 * All rights reserved. 39 * 40 * Export of this software from the United States of America may require 41 * a specific license from the United States Government. It is the 42 * responsibility of any person or organization contemplating export to 43 * obtain such a license before exporting. 44 * 45 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and 46 * distribute this software and its documentation for any purpose and 47 * without fee is hereby granted, provided that the above copyright 48 * notice appear in all copies and that both that copyright notice and 49 * this permission notice appear in supporting documentation, and that 50 * the name of FundsXpress. not be used in advertising or publicity pertaining 51 * to distribution of the software without specific, written prior 52 * permission. FundsXpress makes no representations about the suitability of 53 * this software for any purpose. It is provided "as is" without express 54 * or implied warranty. 55 * 56 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 57 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 58 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 59 */ 60 61 #include <linux/types.h> 62 #include <linux/jiffies.h> 63 #include <linux/sunrpc/gss_krb5.h> 64 #include <linux/random.h> 65 #include <linux/crypto.h> 66 #include <linux/atomic.h> 67 68 #include "gss_krb5_internal.h" 69 70 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 71 # define RPCDBG_FACILITY RPCDBG_AUTH 72 #endif 73 74 #if defined(CONFIG_RPCSEC_GSS_KRB5_SIMPLIFIED) 75 76 static void * 77 setup_token(struct krb5_ctx *ctx, struct xdr_netobj *token) 78 { 79 u16 *ptr; 80 void *krb5_hdr; 81 int body_size = GSS_KRB5_TOK_HDR_LEN + ctx->gk5e->cksumlength; 82 83 token->len = g_token_size(&ctx->mech_used, body_size); 84 85 ptr = (u16 *)token->data; 86 g_make_token_header(&ctx->mech_used, body_size, (unsigned char **)&ptr); 87 88 /* ptr now at start of header described in rfc 1964, section 1.2.1: */ 89 krb5_hdr = ptr; 90 *ptr++ = KG_TOK_MIC_MSG; 91 /* 92 * signalg is stored as if it were converted from LE to host endian, even 93 * though it's an opaque pair of bytes according to the RFC. 94 */ 95 *ptr++ = (__force u16)cpu_to_le16(ctx->gk5e->signalg); 96 *ptr++ = SEAL_ALG_NONE; 97 *ptr = 0xffff; 98 99 return krb5_hdr; 100 } 101 102 u32 103 gss_krb5_get_mic_v1(struct krb5_ctx *ctx, struct xdr_buf *text, 104 struct xdr_netobj *token) 105 { 106 char cksumdata[GSS_KRB5_MAX_CKSUM_LEN]; 107 struct xdr_netobj md5cksum = {.len = sizeof(cksumdata), 108 .data = cksumdata}; 109 void *ptr; 110 time64_t now; 111 u32 seq_send; 112 u8 *cksumkey; 113 114 dprintk("RPC: %s\n", __func__); 115 BUG_ON(ctx == NULL); 116 117 now = ktime_get_real_seconds(); 118 119 ptr = setup_token(ctx, token); 120 121 if (ctx->gk5e->keyed_cksum) 122 cksumkey = ctx->cksum; 123 else 124 cksumkey = NULL; 125 126 if (make_checksum(ctx, ptr, 8, text, 0, cksumkey, 127 KG_USAGE_SIGN, &md5cksum)) 128 return GSS_S_FAILURE; 129 130 memcpy(ptr + GSS_KRB5_TOK_HDR_LEN, md5cksum.data, md5cksum.len); 131 132 seq_send = atomic_fetch_inc(&ctx->seq_send); 133 134 if (krb5_make_seq_num(ctx, ctx->seq, ctx->initiate ? 0 : 0xff, 135 seq_send, ptr + GSS_KRB5_TOK_HDR_LEN, ptr + 8)) 136 return GSS_S_FAILURE; 137 138 return (ctx->endtime < now) ? GSS_S_CONTEXT_EXPIRED : GSS_S_COMPLETE; 139 } 140 141 #endif 142 143 static void * 144 setup_token_v2(struct krb5_ctx *ctx, struct xdr_netobj *token) 145 { 146 u16 *ptr; 147 void *krb5_hdr; 148 u8 *p, flags = 0x00; 149 150 if ((ctx->flags & KRB5_CTX_FLAG_INITIATOR) == 0) 151 flags |= 0x01; 152 if (ctx->flags & KRB5_CTX_FLAG_ACCEPTOR_SUBKEY) 153 flags |= 0x04; 154 155 /* Per rfc 4121, sec 4.2.6.1, there is no header, 156 * just start the token. 157 */ 158 krb5_hdr = (u16 *)token->data; 159 ptr = krb5_hdr; 160 161 *ptr++ = KG2_TOK_MIC; 162 p = (u8 *)ptr; 163 *p++ = flags; 164 *p++ = 0xff; 165 ptr = (u16 *)p; 166 *ptr++ = 0xffff; 167 *ptr = 0xffff; 168 169 token->len = GSS_KRB5_TOK_HDR_LEN + ctx->gk5e->cksumlength; 170 return krb5_hdr; 171 } 172 173 u32 174 gss_krb5_get_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *text, 175 struct xdr_netobj *token) 176 { 177 struct crypto_ahash *tfm = ctx->initiate ? 178 ctx->initiator_sign : ctx->acceptor_sign; 179 struct xdr_netobj cksumobj = { 180 .len = ctx->gk5e->cksumlength, 181 }; 182 __be64 seq_send_be64; 183 void *krb5_hdr; 184 time64_t now; 185 186 dprintk("RPC: %s\n", __func__); 187 188 krb5_hdr = setup_token_v2(ctx, token); 189 190 /* Set up the sequence number. Now 64-bits in clear 191 * text and w/o direction indicator */ 192 seq_send_be64 = cpu_to_be64(atomic64_fetch_inc(&ctx->seq_send64)); 193 memcpy(krb5_hdr + 8, (char *) &seq_send_be64, 8); 194 195 cksumobj.data = krb5_hdr + GSS_KRB5_TOK_HDR_LEN; 196 if (gss_krb5_checksum(tfm, krb5_hdr, GSS_KRB5_TOK_HDR_LEN, 197 text, 0, &cksumobj)) 198 return GSS_S_FAILURE; 199 200 now = ktime_get_real_seconds(); 201 return (ctx->endtime < now) ? GSS_S_CONTEXT_EXPIRED : GSS_S_COMPLETE; 202 } 203