Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/net/sunrpc/gss_generic_token.c |
| 3 | * |
| 4 | * Adapted from MIT Kerberos 5-1.2.1 lib/gssapi/generic/util_token.c |
| 5 | * |
| 6 | * Copyright (c) 2000 The Regents of the University of Michigan. |
| 7 | * All rights reserved. |
| 8 | * |
| 9 | * Andy Adamson <andros@umich.edu> |
| 10 | */ |
| 11 | |
| 12 | /* |
| 13 | * Copyright 1993 by OpenVision Technologies, Inc. |
YOSHIFUJI Hideaki | cca5172 | 2007-02-09 15:38:13 -0800 | [diff] [blame] | 14 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | * Permission to use, copy, modify, distribute, and sell this software |
| 16 | * and its documentation for any purpose is hereby granted without fee, |
| 17 | * provided that the above copyright notice appears in all copies and |
| 18 | * that both that copyright notice and this permission notice appear in |
| 19 | * supporting documentation, and that the name of OpenVision not be used |
| 20 | * in advertising or publicity pertaining to distribution of the software |
| 21 | * without specific, written prior permission. OpenVision makes no |
| 22 | * representations about the suitability of this software for any |
| 23 | * purpose. It is provided "as is" without express or implied warranty. |
YOSHIFUJI Hideaki | cca5172 | 2007-02-09 15:38:13 -0800 | [diff] [blame] | 24 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | * OPENVISION DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, |
| 26 | * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO |
| 27 | * EVENT SHALL OPENVISION BE LIABLE FOR ANY SPECIAL, INDIRECT OR |
| 28 | * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF |
| 29 | * USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR |
| 30 | * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR |
| 31 | * PERFORMANCE OF THIS SOFTWARE. |
| 32 | */ |
| 33 | |
| 34 | #include <linux/types.h> |
| 35 | #include <linux/module.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | #include <linux/string.h> |
| 37 | #include <linux/sunrpc/sched.h> |
| 38 | #include <linux/sunrpc/gss_asn1.h> |
| 39 | |
| 40 | |
Jeff Layton | f895b25 | 2014-11-17 16:58:04 -0500 | [diff] [blame^] | 41 | #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | # define RPCDBG_FACILITY RPCDBG_AUTH |
| 43 | #endif |
| 44 | |
| 45 | |
| 46 | /* TWRITE_STR from gssapiP_generic.h */ |
| 47 | #define TWRITE_STR(ptr, str, len) \ |
| 48 | memcpy((ptr), (char *) (str), (len)); \ |
| 49 | (ptr) += (len); |
| 50 | |
| 51 | /* XXXX this code currently makes the assumption that a mech oid will |
| 52 | never be longer than 127 bytes. This assumption is not inherent in |
| 53 | the interfaces, so the code can be fixed if the OSI namespace |
| 54 | balloons unexpectedly. */ |
| 55 | |
| 56 | /* Each token looks like this: |
| 57 | |
| 58 | 0x60 tag for APPLICATION 0, SEQUENCE |
| 59 | (constructed, definite-length) |
| 60 | <length> possible multiple bytes, need to parse/generate |
| 61 | 0x06 tag for OBJECT IDENTIFIER |
| 62 | <moid_length> compile-time constant string (assume 1 byte) |
| 63 | <moid_bytes> compile-time constant string |
| 64 | <inner_bytes> the ANY containing the application token |
| 65 | bytes 0,1 are the token type |
| 66 | bytes 2,n are the token data |
| 67 | |
| 68 | For the purposes of this abstraction, the token "header" consists of |
| 69 | the sequence tag and length octets, the mech OID DER encoding, and the |
| 70 | first two inner bytes, which indicate the token type. The token |
| 71 | "body" consists of everything else. |
| 72 | |
| 73 | */ |
| 74 | |
| 75 | static int |
| 76 | der_length_size( int length) |
| 77 | { |
| 78 | if (length < (1<<7)) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 79 | return 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | else if (length < (1<<8)) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 81 | return 2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | #if (SIZEOF_INT == 2) |
| 83 | else |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 84 | return 3; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | #else |
| 86 | else if (length < (1<<16)) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 87 | return 3; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 88 | else if (length < (1<<24)) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 89 | return 4; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 90 | else |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 91 | return 5; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 92 | #endif |
| 93 | } |
| 94 | |
| 95 | static void |
| 96 | der_write_length(unsigned char **buf, int length) |
| 97 | { |
| 98 | if (length < (1<<7)) { |
| 99 | *(*buf)++ = (unsigned char) length; |
| 100 | } else { |
| 101 | *(*buf)++ = (unsigned char) (der_length_size(length)+127); |
| 102 | #if (SIZEOF_INT > 2) |
| 103 | if (length >= (1<<24)) |
| 104 | *(*buf)++ = (unsigned char) (length>>24); |
| 105 | if (length >= (1<<16)) |
| 106 | *(*buf)++ = (unsigned char) ((length>>16)&0xff); |
| 107 | #endif |
| 108 | if (length >= (1<<8)) |
| 109 | *(*buf)++ = (unsigned char) ((length>>8)&0xff); |
| 110 | *(*buf)++ = (unsigned char) (length&0xff); |
| 111 | } |
| 112 | } |
| 113 | |
| 114 | /* returns decoded length, or < 0 on failure. Advances buf and |
| 115 | decrements bufsize */ |
| 116 | |
| 117 | static int |
| 118 | der_read_length(unsigned char **buf, int *bufsize) |
| 119 | { |
| 120 | unsigned char sf; |
| 121 | int ret; |
| 122 | |
| 123 | if (*bufsize < 1) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 124 | return -1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 125 | sf = *(*buf)++; |
| 126 | (*bufsize)--; |
| 127 | if (sf & 0x80) { |
| 128 | if ((sf &= 0x7f) > ((*bufsize)-1)) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 129 | return -1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | if (sf > SIZEOF_INT) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 131 | return -1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | ret = 0; |
| 133 | for (; sf; sf--) { |
| 134 | ret = (ret<<8) + (*(*buf)++); |
| 135 | (*bufsize)--; |
| 136 | } |
| 137 | } else { |
| 138 | ret = sf; |
| 139 | } |
| 140 | |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 141 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | } |
| 143 | |
| 144 | /* returns the length of a token, given the mech oid and the body size */ |
| 145 | |
| 146 | int |
| 147 | g_token_size(struct xdr_netobj *mech, unsigned int body_size) |
| 148 | { |
| 149 | /* set body_size to sequence contents size */ |
Kevin Coffman | 4ab4b0b | 2008-03-31 10:31:44 -0400 | [diff] [blame] | 150 | body_size += 2 + (int) mech->len; /* NEED overflow check */ |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 151 | return 1 + der_length_size(body_size) + body_size; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | } |
| 153 | |
Trond Myklebust | 7bd8826 | 2008-12-23 15:21:32 -0500 | [diff] [blame] | 154 | EXPORT_SYMBOL_GPL(g_token_size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 155 | |
| 156 | /* fills in a buffer with the token header. The buffer is assumed to |
| 157 | be the right size. buf is advanced past the token header */ |
| 158 | |
| 159 | void |
| 160 | g_make_token_header(struct xdr_netobj *mech, int body_size, unsigned char **buf) |
| 161 | { |
| 162 | *(*buf)++ = 0x60; |
Kevin Coffman | 4ab4b0b | 2008-03-31 10:31:44 -0400 | [diff] [blame] | 163 | der_write_length(buf, 2 + mech->len + body_size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 164 | *(*buf)++ = 0x06; |
| 165 | *(*buf)++ = (unsigned char) mech->len; |
| 166 | TWRITE_STR(*buf, mech->data, ((int) mech->len)); |
| 167 | } |
| 168 | |
Trond Myklebust | 7bd8826 | 2008-12-23 15:21:32 -0500 | [diff] [blame] | 169 | EXPORT_SYMBOL_GPL(g_make_token_header); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 170 | |
| 171 | /* |
| 172 | * Given a buffer containing a token, reads and verifies the token, |
| 173 | * leaving buf advanced past the token header, and setting body_size |
| 174 | * to the number of remaining bytes. Returns 0 on success, |
| 175 | * G_BAD_TOK_HEADER for a variety of errors, and G_WRONG_MECH if the |
| 176 | * mechanism in the token does not match the mech argument. buf and |
| 177 | * *body_size are left unmodified on error. |
| 178 | */ |
| 179 | u32 |
| 180 | g_verify_token_header(struct xdr_netobj *mech, int *body_size, |
| 181 | unsigned char **buf_in, int toksize) |
| 182 | { |
| 183 | unsigned char *buf = *buf_in; |
| 184 | int seqsize; |
| 185 | struct xdr_netobj toid; |
| 186 | int ret = 0; |
| 187 | |
| 188 | if ((toksize-=1) < 0) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 189 | return G_BAD_TOK_HEADER; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 190 | if (*buf++ != 0x60) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 191 | return G_BAD_TOK_HEADER; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 192 | |
| 193 | if ((seqsize = der_read_length(&buf, &toksize)) < 0) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 194 | return G_BAD_TOK_HEADER; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 195 | |
| 196 | if (seqsize != toksize) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 197 | return G_BAD_TOK_HEADER; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 198 | |
| 199 | if ((toksize-=1) < 0) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 200 | return G_BAD_TOK_HEADER; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 201 | if (*buf++ != 0x06) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 202 | return G_BAD_TOK_HEADER; |
YOSHIFUJI Hideaki | cca5172 | 2007-02-09 15:38:13 -0800 | [diff] [blame] | 203 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 204 | if ((toksize-=1) < 0) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 205 | return G_BAD_TOK_HEADER; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 206 | toid.len = *buf++; |
| 207 | |
| 208 | if ((toksize-=toid.len) < 0) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 209 | return G_BAD_TOK_HEADER; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 210 | toid.data = buf; |
| 211 | buf+=toid.len; |
| 212 | |
YOSHIFUJI Hideaki | cca5172 | 2007-02-09 15:38:13 -0800 | [diff] [blame] | 213 | if (! g_OID_equal(&toid, mech)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | ret = G_WRONG_MECH; |
YOSHIFUJI Hideaki | cca5172 | 2007-02-09 15:38:13 -0800 | [diff] [blame] | 215 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 216 | /* G_WRONG_MECH is not returned immediately because it's more important |
| 217 | to return G_BAD_TOK_HEADER if the token header is in fact bad */ |
| 218 | |
| 219 | if ((toksize-=2) < 0) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 220 | return G_BAD_TOK_HEADER; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 221 | |
| 222 | if (ret) |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 223 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | |
| 225 | if (!ret) { |
| 226 | *buf_in = buf; |
| 227 | *body_size = toksize; |
| 228 | } |
| 229 | |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 230 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | } |
| 232 | |
Trond Myklebust | 7bd8826 | 2008-12-23 15:21:32 -0500 | [diff] [blame] | 233 | EXPORT_SYMBOL_GPL(g_verify_token_header); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | |