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 67#ifdef RPC_DEBUG 68# define RPCDBG_FACILITY RPCDBG_AUTH 69#endif 70 71DEFINE_SPINLOCK(krb5_seq_lock); 72 73static char * 74setup_token(struct krb5_ctx *ctx, struct xdr_netobj *token) 75{ 76 __be16 *ptr, *krb5_hdr; 77 int body_size = GSS_KRB5_TOK_HDR_LEN + ctx->gk5e->cksumlength; 78 79 token->len = g_token_size(&ctx->mech_used, body_size); 80 81 ptr = (__be16 *)token->data; 82 g_make_token_header(&ctx->mech_used, body_size, (unsigned char **)&ptr); 83 84 /* ptr now at start of header described in rfc 1964, section 1.2.1: */ 85 krb5_hdr = ptr; 86 *ptr++ = KG_TOK_MIC_MSG; 87 *ptr++ = cpu_to_le16(ctx->gk5e->signalg); 88 *ptr++ = SEAL_ALG_NONE; 89 *ptr++ = 0xffff; 90 91 return (char *)krb5_hdr; 92} 93 94static void * 95setup_token_v2(struct krb5_ctx *ctx, struct xdr_netobj *token) 96{ 97 __be16 *ptr, *krb5_hdr; 98 u8 *p, flags = 0x00; 99 100 if ((ctx->flags & KRB5_CTX_FLAG_INITIATOR) == 0) 101 flags |= 0x01; 102 if (ctx->flags & KRB5_CTX_FLAG_ACCEPTOR_SUBKEY) 103 flags |= 0x04; 104 105 /* Per rfc 4121, sec 4.2.6.1, there is no header, 106 * just start the token */ 107 krb5_hdr = ptr = (__be16 *)token->data; 108 109 *ptr++ = KG2_TOK_MIC; 110 p = (u8 *)ptr; 111 *p++ = flags; 112 *p++ = 0xff; 113 ptr = (__be16 *)p; 114 *ptr++ = 0xffff; 115 *ptr++ = 0xffff; 116 117 token->len = GSS_KRB5_TOK_HDR_LEN + ctx->gk5e->cksumlength; 118 return krb5_hdr; 119} 120 121static u32 122gss_get_mic_v1(struct krb5_ctx *ctx, struct xdr_buf *text, 123 struct xdr_netobj *token) 124{ 125 char cksumdata[GSS_KRB5_MAX_CKSUM_LEN]; 126 struct xdr_netobj md5cksum = {.len = sizeof(cksumdata), 127 .data = cksumdata}; 128 void *ptr; 129 s32 now; 130 u32 seq_send; 131 u8 *cksumkey; 132 133 dprintk("RPC: %s\n", __func__); 134 BUG_ON(ctx == NULL); 135 136 now = get_seconds(); 137 138 ptr = setup_token(ctx, token); 139 140 if (ctx->gk5e->keyed_cksum) 141 cksumkey = ctx->cksum; 142 else 143 cksumkey = NULL; 144 145 if (make_checksum(ctx, ptr, 8, text, 0, cksumkey, 146 KG_USAGE_SIGN, &md5cksum)) 147 return GSS_S_FAILURE; 148 149 memcpy(ptr + GSS_KRB5_TOK_HDR_LEN, md5cksum.data, md5cksum.len); 150 151 spin_lock(&krb5_seq_lock); 152 seq_send = ctx->seq_send++; 153 spin_unlock(&krb5_seq_lock); 154 155 if (krb5_make_seq_num(ctx, ctx->seq, ctx->initiate ? 0 : 0xff, 156 seq_send, ptr + GSS_KRB5_TOK_HDR_LEN, ptr + 8)) 157 return GSS_S_FAILURE; 158 159 return (ctx->endtime < now) ? GSS_S_CONTEXT_EXPIRED : GSS_S_COMPLETE; 160} 161 162u32 163gss_get_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *text, 164 struct xdr_netobj *token) 165{ 166 char cksumdata[GSS_KRB5_MAX_CKSUM_LEN]; 167 struct xdr_netobj cksumobj = { .len = sizeof(cksumdata), 168 .data = cksumdata}; 169 void *krb5_hdr; 170 s32 now; 171 u64 seq_send; 172 u8 *cksumkey; 173 unsigned int cksum_usage; 174 175 dprintk("RPC: %s\n", __func__); 176 177 krb5_hdr = setup_token_v2(ctx, token); 178 179 /* Set up the sequence number. Now 64-bits in clear 180 * text and w/o direction indicator */ 181 spin_lock(&krb5_seq_lock); 182 seq_send = ctx->seq_send64++; 183 spin_unlock(&krb5_seq_lock); 184 *((u64 *)(krb5_hdr + 8)) = cpu_to_be64(seq_send); 185 186 if (ctx->initiate) { 187 cksumkey = ctx->initiator_sign; 188 cksum_usage = KG_USAGE_INITIATOR_SIGN; 189 } else { 190 cksumkey = ctx->acceptor_sign; 191 cksum_usage = KG_USAGE_ACCEPTOR_SIGN; 192 } 193 194 if (make_checksum_v2(ctx, krb5_hdr, GSS_KRB5_TOK_HDR_LEN, 195 text, 0, cksumkey, cksum_usage, &cksumobj)) 196 return GSS_S_FAILURE; 197 198 memcpy(krb5_hdr + GSS_KRB5_TOK_HDR_LEN, cksumobj.data, cksumobj.len); 199 200 now = get_seconds(); 201 202 return (ctx->endtime < now) ? GSS_S_CONTEXT_EXPIRED : GSS_S_COMPLETE; 203} 204 205u32 206gss_get_mic_kerberos(struct gss_ctx *gss_ctx, struct xdr_buf *text, 207 struct xdr_netobj *token) 208{ 209 struct krb5_ctx *ctx = gss_ctx->internal_ctx_id; 210 211 switch (ctx->enctype) { 212 default: 213 BUG(); 214 case ENCTYPE_DES_CBC_RAW: 215 case ENCTYPE_DES3_CBC_RAW: 216 case ENCTYPE_ARCFOUR_HMAC: 217 return gss_get_mic_v1(ctx, text, token); 218 case ENCTYPE_AES128_CTS_HMAC_SHA1_96: 219 case ENCTYPE_AES256_CTS_HMAC_SHA1_96: 220 return gss_get_mic_v2(ctx, text, token); 221 } 222} 223