David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1 | /* Kerberos-based RxRPC security |
| 2 | * |
| 3 | * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. |
| 4 | * Written by David Howells (dhowells@redhat.com) |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | */ |
| 11 | |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 12 | #include <crypto/skcipher.h> |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 13 | #include <linux/module.h> |
| 14 | #include <linux/net.h> |
| 15 | #include <linux/skbuff.h> |
| 16 | #include <linux/udp.h> |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 17 | #include <linux/scatterlist.h> |
| 18 | #include <linux/ctype.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 19 | #include <linux/slab.h> |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 20 | #include <net/sock.h> |
| 21 | #include <net/af_rxrpc.h> |
David Howells | 3394128 | 2009-09-14 01:17:35 +0000 | [diff] [blame] | 22 | #include <keys/rxrpc-type.h> |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 23 | #include "ar-internal.h" |
| 24 | |
| 25 | #define RXKAD_VERSION 2 |
| 26 | #define MAXKRB5TICKETLEN 1024 |
| 27 | #define RXKAD_TKT_TYPE_KERBEROS_V5 256 |
| 28 | #define ANAME_SZ 40 /* size of authentication name */ |
| 29 | #define INST_SZ 40 /* size of principal's instance */ |
| 30 | #define REALM_SZ 40 /* size of principal's auth domain */ |
| 31 | #define SNAME_SZ 40 /* size of service name */ |
| 32 | |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 33 | struct rxkad_level1_hdr { |
| 34 | __be32 data_size; /* true data size (excluding padding) */ |
| 35 | }; |
| 36 | |
| 37 | struct rxkad_level2_hdr { |
| 38 | __be32 data_size; /* true data size (excluding padding) */ |
| 39 | __be32 checksum; /* decrypted data checksum */ |
| 40 | }; |
| 41 | |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 42 | /* |
| 43 | * this holds a pinned cipher so that keventd doesn't get called by the cipher |
| 44 | * alloc routine, but since we have it to hand, we use it to decrypt RESPONSE |
| 45 | * packets |
| 46 | */ |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 47 | static struct crypto_skcipher *rxkad_ci; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 48 | static DEFINE_MUTEX(rxkad_ci_mutex); |
| 49 | |
| 50 | /* |
| 51 | * initialise connection security |
| 52 | */ |
| 53 | static int rxkad_init_connection_security(struct rxrpc_connection *conn) |
| 54 | { |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 55 | struct crypto_skcipher *ci; |
David Howells | 3394128 | 2009-09-14 01:17:35 +0000 | [diff] [blame] | 56 | struct rxrpc_key_token *token; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 57 | int ret; |
| 58 | |
| 59 | _enter("{%d},{%x}", conn->debug_id, key_serial(conn->key)); |
| 60 | |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 61 | token = conn->key->payload.data[0]; |
David Howells | 3394128 | 2009-09-14 01:17:35 +0000 | [diff] [blame] | 62 | conn->security_ix = token->security_index; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 63 | |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 64 | ci = crypto_alloc_skcipher("pcbc(fcrypt)", 0, CRYPTO_ALG_ASYNC); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 65 | if (IS_ERR(ci)) { |
| 66 | _debug("no cipher"); |
| 67 | ret = PTR_ERR(ci); |
| 68 | goto error; |
| 69 | } |
| 70 | |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 71 | if (crypto_skcipher_setkey(ci, token->kad->session_key, |
| 72 | sizeof(token->kad->session_key)) < 0) |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 73 | BUG(); |
| 74 | |
| 75 | switch (conn->security_level) { |
| 76 | case RXRPC_SECURITY_PLAIN: |
| 77 | break; |
| 78 | case RXRPC_SECURITY_AUTH: |
| 79 | conn->size_align = 8; |
| 80 | conn->security_size = sizeof(struct rxkad_level1_hdr); |
| 81 | conn->header_size += sizeof(struct rxkad_level1_hdr); |
| 82 | break; |
| 83 | case RXRPC_SECURITY_ENCRYPT: |
| 84 | conn->size_align = 8; |
| 85 | conn->security_size = sizeof(struct rxkad_level2_hdr); |
| 86 | conn->header_size += sizeof(struct rxkad_level2_hdr); |
| 87 | break; |
| 88 | default: |
| 89 | ret = -EKEYREJECTED; |
| 90 | goto error; |
| 91 | } |
| 92 | |
| 93 | conn->cipher = ci; |
| 94 | ret = 0; |
| 95 | error: |
| 96 | _leave(" = %d", ret); |
| 97 | return ret; |
| 98 | } |
| 99 | |
| 100 | /* |
| 101 | * prime the encryption state with the invariant parts of a connection's |
| 102 | * description |
| 103 | */ |
| 104 | static void rxkad_prime_packet_security(struct rxrpc_connection *conn) |
| 105 | { |
David Howells | 3394128 | 2009-09-14 01:17:35 +0000 | [diff] [blame] | 106 | struct rxrpc_key_token *token; |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 107 | SKCIPHER_REQUEST_ON_STACK(req, conn->cipher); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 108 | struct scatterlist sg[2]; |
| 109 | struct rxrpc_crypt iv; |
| 110 | struct { |
| 111 | __be32 x[4]; |
| 112 | } tmpbuf __attribute__((aligned(16))); /* must all be in same page */ |
| 113 | |
| 114 | _enter(""); |
| 115 | |
| 116 | if (!conn->key) |
| 117 | return; |
| 118 | |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 119 | token = conn->key->payload.data[0]; |
David Howells | 3394128 | 2009-09-14 01:17:35 +0000 | [diff] [blame] | 120 | memcpy(&iv, token->kad->session_key, sizeof(iv)); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 121 | |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 122 | tmpbuf.x[0] = htonl(conn->epoch); |
| 123 | tmpbuf.x[1] = htonl(conn->cid); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 124 | tmpbuf.x[2] = 0; |
| 125 | tmpbuf.x[3] = htonl(conn->security_ix); |
| 126 | |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 127 | sg_init_one(&sg[0], &tmpbuf, sizeof(tmpbuf)); |
| 128 | sg_init_one(&sg[1], &tmpbuf, sizeof(tmpbuf)); |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 129 | |
| 130 | skcipher_request_set_tfm(req, conn->cipher); |
| 131 | skcipher_request_set_callback(req, 0, NULL, NULL); |
| 132 | skcipher_request_set_crypt(req, &sg[1], &sg[0], sizeof(tmpbuf), iv.x); |
| 133 | |
| 134 | crypto_skcipher_encrypt(req); |
| 135 | skcipher_request_zero(req); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 136 | |
| 137 | memcpy(&conn->csum_iv, &tmpbuf.x[2], sizeof(conn->csum_iv)); |
David Howells | 2b15ef1 | 2016-03-04 15:59:13 +0000 | [diff] [blame] | 138 | ASSERTCMP((u32 __force)conn->csum_iv.n[0], ==, (u32 __force)tmpbuf.x[2]); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 139 | |
| 140 | _leave(""); |
| 141 | } |
| 142 | |
| 143 | /* |
| 144 | * partially encrypt a packet (level 1 security) |
| 145 | */ |
| 146 | static int rxkad_secure_packet_auth(const struct rxrpc_call *call, |
| 147 | struct sk_buff *skb, |
| 148 | u32 data_size, |
| 149 | void *sechdr) |
| 150 | { |
| 151 | struct rxrpc_skb_priv *sp; |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 152 | SKCIPHER_REQUEST_ON_STACK(req, call->conn->cipher); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 153 | struct rxrpc_crypt iv; |
| 154 | struct scatterlist sg[2]; |
| 155 | struct { |
| 156 | struct rxkad_level1_hdr hdr; |
| 157 | __be32 first; /* first four bytes of data and padding */ |
| 158 | } tmpbuf __attribute__((aligned(8))); /* must all be in same page */ |
| 159 | u16 check; |
| 160 | |
| 161 | sp = rxrpc_skb(skb); |
| 162 | |
| 163 | _enter(""); |
| 164 | |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 165 | check = sp->hdr.seq ^ sp->hdr.callNumber; |
| 166 | data_size |= (u32)check << 16; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 167 | |
| 168 | tmpbuf.hdr.data_size = htonl(data_size); |
| 169 | memcpy(&tmpbuf.first, sechdr + 4, sizeof(tmpbuf.first)); |
| 170 | |
| 171 | /* start the encryption afresh */ |
| 172 | memset(&iv, 0, sizeof(iv)); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 173 | |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 174 | sg_init_one(&sg[0], &tmpbuf, sizeof(tmpbuf)); |
| 175 | sg_init_one(&sg[1], &tmpbuf, sizeof(tmpbuf)); |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 176 | |
| 177 | skcipher_request_set_tfm(req, call->conn->cipher); |
| 178 | skcipher_request_set_callback(req, 0, NULL, NULL); |
| 179 | skcipher_request_set_crypt(req, &sg[1], &sg[0], sizeof(tmpbuf), iv.x); |
| 180 | |
| 181 | crypto_skcipher_encrypt(req); |
| 182 | skcipher_request_zero(req); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 183 | |
| 184 | memcpy(sechdr, &tmpbuf, sizeof(tmpbuf)); |
| 185 | |
| 186 | _leave(" = 0"); |
| 187 | return 0; |
| 188 | } |
| 189 | |
| 190 | /* |
| 191 | * wholly encrypt a packet (level 2 security) |
| 192 | */ |
| 193 | static int rxkad_secure_packet_encrypt(const struct rxrpc_call *call, |
David Howells | b4f1342 | 2016-03-04 15:56:19 +0000 | [diff] [blame] | 194 | struct sk_buff *skb, |
| 195 | u32 data_size, |
| 196 | void *sechdr) |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 197 | { |
David Howells | 3394128 | 2009-09-14 01:17:35 +0000 | [diff] [blame] | 198 | const struct rxrpc_key_token *token; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 199 | struct rxkad_level2_hdr rxkhdr |
| 200 | __attribute__((aligned(8))); /* must be all on one page */ |
| 201 | struct rxrpc_skb_priv *sp; |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 202 | SKCIPHER_REQUEST_ON_STACK(req, call->conn->cipher); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 203 | struct rxrpc_crypt iv; |
| 204 | struct scatterlist sg[16]; |
| 205 | struct sk_buff *trailer; |
Eric Dumazet | 95c9617 | 2012-04-15 05:58:06 +0000 | [diff] [blame] | 206 | unsigned int len; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 207 | u16 check; |
| 208 | int nsg; |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 209 | int err; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 210 | |
| 211 | sp = rxrpc_skb(skb); |
| 212 | |
| 213 | _enter(""); |
| 214 | |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 215 | check = sp->hdr.seq ^ sp->hdr.callNumber; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 216 | |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 217 | rxkhdr.data_size = htonl(data_size | (u32)check << 16); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 218 | rxkhdr.checksum = 0; |
| 219 | |
| 220 | /* encrypt from the session key */ |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 221 | token = call->conn->key->payload.data[0]; |
David Howells | 3394128 | 2009-09-14 01:17:35 +0000 | [diff] [blame] | 222 | memcpy(&iv, token->kad->session_key, sizeof(iv)); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 223 | |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 224 | sg_init_one(&sg[0], sechdr, sizeof(rxkhdr)); |
| 225 | sg_init_one(&sg[1], &rxkhdr, sizeof(rxkhdr)); |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 226 | |
| 227 | skcipher_request_set_tfm(req, call->conn->cipher); |
| 228 | skcipher_request_set_callback(req, 0, NULL, NULL); |
| 229 | skcipher_request_set_crypt(req, &sg[1], &sg[0], sizeof(rxkhdr), iv.x); |
| 230 | |
| 231 | crypto_skcipher_encrypt(req); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 232 | |
| 233 | /* we want to encrypt the skbuff in-place */ |
| 234 | nsg = skb_cow_data(skb, 0, &trailer); |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 235 | err = -ENOMEM; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 236 | if (nsg < 0 || nsg > 16) |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 237 | goto out; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 238 | |
| 239 | len = data_size + call->conn->size_align - 1; |
| 240 | len &= ~(call->conn->size_align - 1); |
| 241 | |
David S. Miller | 51c739d | 2007-10-30 21:29:29 -0700 | [diff] [blame] | 242 | sg_init_table(sg, nsg); |
| 243 | skb_to_sgvec(skb, sg, 0, len); |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 244 | |
| 245 | skcipher_request_set_crypt(req, sg, sg, len, iv.x); |
| 246 | |
| 247 | crypto_skcipher_encrypt(req); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 248 | |
| 249 | _leave(" = 0"); |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 250 | err = 0; |
| 251 | |
| 252 | out: |
| 253 | skcipher_request_zero(req); |
| 254 | return err; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 255 | } |
| 256 | |
| 257 | /* |
| 258 | * checksum an RxRPC packet header |
| 259 | */ |
| 260 | static int rxkad_secure_packet(const struct rxrpc_call *call, |
David Howells | b4f1342 | 2016-03-04 15:56:19 +0000 | [diff] [blame] | 261 | struct sk_buff *skb, |
| 262 | size_t data_size, |
| 263 | void *sechdr) |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 264 | { |
| 265 | struct rxrpc_skb_priv *sp; |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 266 | SKCIPHER_REQUEST_ON_STACK(req, call->conn->cipher); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 267 | struct rxrpc_crypt iv; |
| 268 | struct scatterlist sg[2]; |
| 269 | struct { |
| 270 | __be32 x[2]; |
| 271 | } tmpbuf __attribute__((aligned(8))); /* must all be in same page */ |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 272 | u32 x, y; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 273 | int ret; |
| 274 | |
| 275 | sp = rxrpc_skb(skb); |
| 276 | |
| 277 | _enter("{%d{%x}},{#%u},%zu,", |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 278 | call->debug_id, key_serial(call->conn->key), sp->hdr.seq, |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 279 | data_size); |
| 280 | |
| 281 | if (!call->conn->cipher) |
| 282 | return 0; |
| 283 | |
| 284 | ret = key_validate(call->conn->key); |
| 285 | if (ret < 0) |
| 286 | return ret; |
| 287 | |
| 288 | /* continue encrypting from where we left off */ |
| 289 | memcpy(&iv, call->conn->csum_iv.x, sizeof(iv)); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 290 | |
| 291 | /* calculate the security checksum */ |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 292 | x = call->channel << (32 - RXRPC_CIDSHIFT); |
| 293 | x |= sp->hdr.seq & 0x3fffffff; |
| 294 | tmpbuf.x[0] = htonl(sp->hdr.callNumber); |
| 295 | tmpbuf.x[1] = htonl(x); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 296 | |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 297 | sg_init_one(&sg[0], &tmpbuf, sizeof(tmpbuf)); |
| 298 | sg_init_one(&sg[1], &tmpbuf, sizeof(tmpbuf)); |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 299 | |
| 300 | skcipher_request_set_tfm(req, call->conn->cipher); |
| 301 | skcipher_request_set_callback(req, 0, NULL, NULL); |
| 302 | skcipher_request_set_crypt(req, &sg[1], &sg[0], sizeof(tmpbuf), iv.x); |
| 303 | |
| 304 | crypto_skcipher_encrypt(req); |
| 305 | skcipher_request_zero(req); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 306 | |
Al Viro | 91e916c | 2008-03-29 03:08:38 +0000 | [diff] [blame] | 307 | y = ntohl(tmpbuf.x[1]); |
| 308 | y = (y >> 16) & 0xffff; |
| 309 | if (y == 0) |
| 310 | y = 1; /* zero checksums are not permitted */ |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 311 | sp->hdr.cksum = y; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 312 | |
| 313 | switch (call->conn->security_level) { |
| 314 | case RXRPC_SECURITY_PLAIN: |
| 315 | ret = 0; |
| 316 | break; |
| 317 | case RXRPC_SECURITY_AUTH: |
| 318 | ret = rxkad_secure_packet_auth(call, skb, data_size, sechdr); |
| 319 | break; |
| 320 | case RXRPC_SECURITY_ENCRYPT: |
| 321 | ret = rxkad_secure_packet_encrypt(call, skb, data_size, |
| 322 | sechdr); |
| 323 | break; |
| 324 | default: |
| 325 | ret = -EPERM; |
| 326 | break; |
| 327 | } |
| 328 | |
Al Viro | 91e916c | 2008-03-29 03:08:38 +0000 | [diff] [blame] | 329 | _leave(" = %d [set %hx]", ret, y); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 330 | return ret; |
| 331 | } |
| 332 | |
| 333 | /* |
| 334 | * decrypt partial encryption on a packet (level 1 security) |
| 335 | */ |
| 336 | static int rxkad_verify_packet_auth(const struct rxrpc_call *call, |
| 337 | struct sk_buff *skb, |
| 338 | u32 *_abort_code) |
| 339 | { |
| 340 | struct rxkad_level1_hdr sechdr; |
| 341 | struct rxrpc_skb_priv *sp; |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 342 | SKCIPHER_REQUEST_ON_STACK(req, call->conn->cipher); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 343 | struct rxrpc_crypt iv; |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 344 | struct scatterlist sg[16]; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 345 | struct sk_buff *trailer; |
| 346 | u32 data_size, buf; |
| 347 | u16 check; |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 348 | int nsg; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 349 | |
| 350 | _enter(""); |
| 351 | |
| 352 | sp = rxrpc_skb(skb); |
| 353 | |
| 354 | /* we want to decrypt the skbuff in-place */ |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 355 | nsg = skb_cow_data(skb, 0, &trailer); |
| 356 | if (nsg < 0 || nsg > 16) |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 357 | goto nomem; |
| 358 | |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 359 | sg_init_table(sg, nsg); |
David S. Miller | 51c739d | 2007-10-30 21:29:29 -0700 | [diff] [blame] | 360 | skb_to_sgvec(skb, sg, 0, 8); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 361 | |
| 362 | /* start the decryption afresh */ |
| 363 | memset(&iv, 0, sizeof(iv)); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 364 | |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 365 | skcipher_request_set_tfm(req, call->conn->cipher); |
| 366 | skcipher_request_set_callback(req, 0, NULL, NULL); |
| 367 | skcipher_request_set_crypt(req, sg, sg, 8, iv.x); |
| 368 | |
| 369 | crypto_skcipher_decrypt(req); |
| 370 | skcipher_request_zero(req); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 371 | |
| 372 | /* remove the decrypted packet length */ |
| 373 | if (skb_copy_bits(skb, 0, &sechdr, sizeof(sechdr)) < 0) |
| 374 | goto datalen_error; |
| 375 | if (!skb_pull(skb, sizeof(sechdr))) |
| 376 | BUG(); |
| 377 | |
| 378 | buf = ntohl(sechdr.data_size); |
| 379 | data_size = buf & 0xffff; |
| 380 | |
| 381 | check = buf >> 16; |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 382 | check ^= sp->hdr.seq ^ sp->hdr.callNumber; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 383 | check &= 0xffff; |
| 384 | if (check != 0) { |
| 385 | *_abort_code = RXKADSEALEDINCON; |
| 386 | goto protocol_error; |
| 387 | } |
| 388 | |
| 389 | /* shorten the packet to remove the padding */ |
| 390 | if (data_size > skb->len) |
| 391 | goto datalen_error; |
| 392 | else if (data_size < skb->len) |
| 393 | skb->len = data_size; |
| 394 | |
| 395 | _leave(" = 0 [dlen=%x]", data_size); |
| 396 | return 0; |
| 397 | |
| 398 | datalen_error: |
| 399 | *_abort_code = RXKADDATALEN; |
| 400 | protocol_error: |
| 401 | _leave(" = -EPROTO"); |
| 402 | return -EPROTO; |
| 403 | |
| 404 | nomem: |
| 405 | _leave(" = -ENOMEM"); |
| 406 | return -ENOMEM; |
| 407 | } |
| 408 | |
| 409 | /* |
| 410 | * wholly decrypt a packet (level 2 security) |
| 411 | */ |
| 412 | static int rxkad_verify_packet_encrypt(const struct rxrpc_call *call, |
| 413 | struct sk_buff *skb, |
| 414 | u32 *_abort_code) |
| 415 | { |
David Howells | 3394128 | 2009-09-14 01:17:35 +0000 | [diff] [blame] | 416 | const struct rxrpc_key_token *token; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 417 | struct rxkad_level2_hdr sechdr; |
| 418 | struct rxrpc_skb_priv *sp; |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 419 | SKCIPHER_REQUEST_ON_STACK(req, call->conn->cipher); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 420 | struct rxrpc_crypt iv; |
| 421 | struct scatterlist _sg[4], *sg; |
| 422 | struct sk_buff *trailer; |
| 423 | u32 data_size, buf; |
| 424 | u16 check; |
| 425 | int nsg; |
| 426 | |
| 427 | _enter(",{%d}", skb->len); |
| 428 | |
| 429 | sp = rxrpc_skb(skb); |
| 430 | |
| 431 | /* we want to decrypt the skbuff in-place */ |
| 432 | nsg = skb_cow_data(skb, 0, &trailer); |
| 433 | if (nsg < 0) |
| 434 | goto nomem; |
| 435 | |
| 436 | sg = _sg; |
| 437 | if (unlikely(nsg > 4)) { |
| 438 | sg = kmalloc(sizeof(*sg) * nsg, GFP_NOIO); |
| 439 | if (!sg) |
| 440 | goto nomem; |
| 441 | } |
| 442 | |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 443 | sg_init_table(sg, nsg); |
David S. Miller | 51c739d | 2007-10-30 21:29:29 -0700 | [diff] [blame] | 444 | skb_to_sgvec(skb, sg, 0, skb->len); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 445 | |
| 446 | /* decrypt from the session key */ |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 447 | token = call->conn->key->payload.data[0]; |
David Howells | 3394128 | 2009-09-14 01:17:35 +0000 | [diff] [blame] | 448 | memcpy(&iv, token->kad->session_key, sizeof(iv)); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 449 | |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 450 | skcipher_request_set_tfm(req, call->conn->cipher); |
| 451 | skcipher_request_set_callback(req, 0, NULL, NULL); |
| 452 | skcipher_request_set_crypt(req, sg, sg, skb->len, iv.x); |
| 453 | |
| 454 | crypto_skcipher_decrypt(req); |
| 455 | skcipher_request_zero(req); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 456 | if (sg != _sg) |
| 457 | kfree(sg); |
| 458 | |
| 459 | /* remove the decrypted packet length */ |
| 460 | if (skb_copy_bits(skb, 0, &sechdr, sizeof(sechdr)) < 0) |
| 461 | goto datalen_error; |
| 462 | if (!skb_pull(skb, sizeof(sechdr))) |
| 463 | BUG(); |
| 464 | |
| 465 | buf = ntohl(sechdr.data_size); |
| 466 | data_size = buf & 0xffff; |
| 467 | |
| 468 | check = buf >> 16; |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 469 | check ^= sp->hdr.seq ^ sp->hdr.callNumber; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 470 | check &= 0xffff; |
| 471 | if (check != 0) { |
| 472 | *_abort_code = RXKADSEALEDINCON; |
| 473 | goto protocol_error; |
| 474 | } |
| 475 | |
| 476 | /* shorten the packet to remove the padding */ |
| 477 | if (data_size > skb->len) |
| 478 | goto datalen_error; |
| 479 | else if (data_size < skb->len) |
| 480 | skb->len = data_size; |
| 481 | |
| 482 | _leave(" = 0 [dlen=%x]", data_size); |
| 483 | return 0; |
| 484 | |
| 485 | datalen_error: |
| 486 | *_abort_code = RXKADDATALEN; |
| 487 | protocol_error: |
| 488 | _leave(" = -EPROTO"); |
| 489 | return -EPROTO; |
| 490 | |
| 491 | nomem: |
| 492 | _leave(" = -ENOMEM"); |
| 493 | return -ENOMEM; |
| 494 | } |
| 495 | |
| 496 | /* |
| 497 | * verify the security on a received packet |
| 498 | */ |
| 499 | static int rxkad_verify_packet(const struct rxrpc_call *call, |
| 500 | struct sk_buff *skb, |
| 501 | u32 *_abort_code) |
| 502 | { |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 503 | SKCIPHER_REQUEST_ON_STACK(req, call->conn->cipher); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 504 | struct rxrpc_skb_priv *sp; |
| 505 | struct rxrpc_crypt iv; |
| 506 | struct scatterlist sg[2]; |
| 507 | struct { |
| 508 | __be32 x[2]; |
| 509 | } tmpbuf __attribute__((aligned(8))); /* must all be in same page */ |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 510 | u16 cksum; |
| 511 | u32 x, y; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 512 | int ret; |
| 513 | |
| 514 | sp = rxrpc_skb(skb); |
| 515 | |
| 516 | _enter("{%d{%x}},{#%u}", |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 517 | call->debug_id, key_serial(call->conn->key), sp->hdr.seq); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 518 | |
| 519 | if (!call->conn->cipher) |
| 520 | return 0; |
| 521 | |
David Howells | 8b81547 | 2009-09-14 01:17:30 +0000 | [diff] [blame] | 522 | if (sp->hdr.securityIndex != RXRPC_SECURITY_RXKAD) { |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 523 | *_abort_code = RXKADINCONSISTENCY; |
| 524 | _leave(" = -EPROTO [not rxkad]"); |
| 525 | return -EPROTO; |
| 526 | } |
| 527 | |
| 528 | /* continue encrypting from where we left off */ |
| 529 | memcpy(&iv, call->conn->csum_iv.x, sizeof(iv)); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 530 | |
| 531 | /* validate the security checksum */ |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 532 | x = call->channel << (32 - RXRPC_CIDSHIFT); |
| 533 | x |= sp->hdr.seq & 0x3fffffff; |
| 534 | tmpbuf.x[0] = htonl(call->call_id); |
| 535 | tmpbuf.x[1] = htonl(x); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 536 | |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 537 | sg_init_one(&sg[0], &tmpbuf, sizeof(tmpbuf)); |
| 538 | sg_init_one(&sg[1], &tmpbuf, sizeof(tmpbuf)); |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 539 | |
| 540 | skcipher_request_set_tfm(req, call->conn->cipher); |
| 541 | skcipher_request_set_callback(req, 0, NULL, NULL); |
| 542 | skcipher_request_set_crypt(req, &sg[1], &sg[0], sizeof(tmpbuf), iv.x); |
| 543 | |
| 544 | crypto_skcipher_encrypt(req); |
| 545 | skcipher_request_zero(req); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 546 | |
Al Viro | 91e916c | 2008-03-29 03:08:38 +0000 | [diff] [blame] | 547 | y = ntohl(tmpbuf.x[1]); |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 548 | cksum = (y >> 16) & 0xffff; |
| 549 | if (cksum == 0) |
| 550 | cksum = 1; /* zero checksums are not permitted */ |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 551 | |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 552 | if (sp->hdr.cksum != cksum) { |
| 553 | *_abort_code = RXKADSEALEDINCON; |
| 554 | _leave(" = -EPROTO [csum failed]"); |
| 555 | return -EPROTO; |
| 556 | } |
| 557 | |
| 558 | switch (call->conn->security_level) { |
| 559 | case RXRPC_SECURITY_PLAIN: |
| 560 | ret = 0; |
| 561 | break; |
| 562 | case RXRPC_SECURITY_AUTH: |
| 563 | ret = rxkad_verify_packet_auth(call, skb, _abort_code); |
| 564 | break; |
| 565 | case RXRPC_SECURITY_ENCRYPT: |
| 566 | ret = rxkad_verify_packet_encrypt(call, skb, _abort_code); |
| 567 | break; |
| 568 | default: |
| 569 | ret = -ENOANO; |
| 570 | break; |
| 571 | } |
| 572 | |
| 573 | _leave(" = %d", ret); |
| 574 | return ret; |
| 575 | } |
| 576 | |
| 577 | /* |
| 578 | * issue a challenge |
| 579 | */ |
| 580 | static int rxkad_issue_challenge(struct rxrpc_connection *conn) |
| 581 | { |
| 582 | struct rxkad_challenge challenge; |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 583 | struct rxrpc_wire_header whdr; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 584 | struct msghdr msg; |
| 585 | struct kvec iov[2]; |
| 586 | size_t len; |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 587 | u32 serial; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 588 | int ret; |
| 589 | |
| 590 | _enter("{%d,%x}", conn->debug_id, key_serial(conn->key)); |
| 591 | |
| 592 | ret = key_validate(conn->key); |
| 593 | if (ret < 0) |
| 594 | return ret; |
| 595 | |
| 596 | get_random_bytes(&conn->security_nonce, sizeof(conn->security_nonce)); |
| 597 | |
| 598 | challenge.version = htonl(2); |
| 599 | challenge.nonce = htonl(conn->security_nonce); |
| 600 | challenge.min_level = htonl(0); |
| 601 | challenge.__padding = 0; |
| 602 | |
| 603 | msg.msg_name = &conn->trans->peer->srx.transport.sin; |
| 604 | msg.msg_namelen = sizeof(conn->trans->peer->srx.transport.sin); |
| 605 | msg.msg_control = NULL; |
| 606 | msg.msg_controllen = 0; |
| 607 | msg.msg_flags = 0; |
| 608 | |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 609 | whdr.epoch = htonl(conn->epoch); |
| 610 | whdr.cid = htonl(conn->cid); |
| 611 | whdr.callNumber = 0; |
| 612 | whdr.seq = 0; |
| 613 | whdr.type = RXRPC_PACKET_TYPE_CHALLENGE; |
| 614 | whdr.flags = conn->out_clientflag; |
| 615 | whdr.userStatus = 0; |
| 616 | whdr.securityIndex = conn->security_ix; |
| 617 | whdr._rsvd = 0; |
| 618 | whdr.serviceId = htons(conn->service_id); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 619 | |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 620 | iov[0].iov_base = &whdr; |
| 621 | iov[0].iov_len = sizeof(whdr); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 622 | iov[1].iov_base = &challenge; |
| 623 | iov[1].iov_len = sizeof(challenge); |
| 624 | |
| 625 | len = iov[0].iov_len + iov[1].iov_len; |
| 626 | |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 627 | serial = atomic_inc_return(&conn->serial); |
| 628 | whdr.serial = htonl(serial); |
| 629 | _proto("Tx CHALLENGE %%%u", serial); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 630 | |
| 631 | ret = kernel_sendmsg(conn->trans->local->socket, &msg, iov, 2, len); |
| 632 | if (ret < 0) { |
| 633 | _debug("sendmsg failed: %d", ret); |
| 634 | return -EAGAIN; |
| 635 | } |
| 636 | |
| 637 | _leave(" = 0"); |
| 638 | return 0; |
| 639 | } |
| 640 | |
| 641 | /* |
| 642 | * send a Kerberos security response |
| 643 | */ |
| 644 | static int rxkad_send_response(struct rxrpc_connection *conn, |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 645 | struct rxrpc_host_header *hdr, |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 646 | struct rxkad_response *resp, |
| 647 | const struct rxkad_key *s2) |
| 648 | { |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 649 | struct rxrpc_wire_header whdr; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 650 | struct msghdr msg; |
| 651 | struct kvec iov[3]; |
| 652 | size_t len; |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 653 | u32 serial; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 654 | int ret; |
| 655 | |
| 656 | _enter(""); |
| 657 | |
| 658 | msg.msg_name = &conn->trans->peer->srx.transport.sin; |
| 659 | msg.msg_namelen = sizeof(conn->trans->peer->srx.transport.sin); |
| 660 | msg.msg_control = NULL; |
| 661 | msg.msg_controllen = 0; |
| 662 | msg.msg_flags = 0; |
| 663 | |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 664 | memset(&whdr, 0, sizeof(whdr)); |
| 665 | whdr.epoch = htonl(hdr->epoch); |
| 666 | whdr.cid = htonl(hdr->cid); |
| 667 | whdr.type = RXRPC_PACKET_TYPE_RESPONSE; |
| 668 | whdr.flags = conn->out_clientflag; |
| 669 | whdr.securityIndex = hdr->securityIndex; |
| 670 | whdr.serviceId = htons(hdr->serviceId); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 671 | |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 672 | iov[0].iov_base = &whdr; |
| 673 | iov[0].iov_len = sizeof(whdr); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 674 | iov[1].iov_base = resp; |
| 675 | iov[1].iov_len = sizeof(*resp); |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 676 | iov[2].iov_base = (void *)s2->ticket; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 677 | iov[2].iov_len = s2->ticket_len; |
| 678 | |
| 679 | len = iov[0].iov_len + iov[1].iov_len + iov[2].iov_len; |
| 680 | |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 681 | serial = atomic_inc_return(&conn->serial); |
| 682 | whdr.serial = htonl(serial); |
| 683 | _proto("Tx RESPONSE %%%u", serial); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 684 | |
| 685 | ret = kernel_sendmsg(conn->trans->local->socket, &msg, iov, 3, len); |
| 686 | if (ret < 0) { |
| 687 | _debug("sendmsg failed: %d", ret); |
| 688 | return -EAGAIN; |
| 689 | } |
| 690 | |
| 691 | _leave(" = 0"); |
| 692 | return 0; |
| 693 | } |
| 694 | |
| 695 | /* |
| 696 | * calculate the response checksum |
| 697 | */ |
| 698 | static void rxkad_calc_response_checksum(struct rxkad_response *response) |
| 699 | { |
| 700 | u32 csum = 1000003; |
| 701 | int loop; |
| 702 | u8 *p = (u8 *) response; |
| 703 | |
| 704 | for (loop = sizeof(*response); loop > 0; loop--) |
| 705 | csum = csum * 0x10204081 + *p++; |
| 706 | |
| 707 | response->encrypted.checksum = htonl(csum); |
| 708 | } |
| 709 | |
| 710 | /* |
| 711 | * load a scatterlist with a potentially split-page buffer |
| 712 | */ |
| 713 | static void rxkad_sg_set_buf2(struct scatterlist sg[2], |
| 714 | void *buf, size_t buflen) |
| 715 | { |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 716 | int nsg = 1; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 717 | |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 718 | sg_init_table(sg, 2); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 719 | |
| 720 | sg_set_buf(&sg[0], buf, buflen); |
| 721 | if (sg[0].offset + buflen > PAGE_SIZE) { |
| 722 | /* the buffer was split over two pages */ |
| 723 | sg[0].length = PAGE_SIZE - sg[0].offset; |
| 724 | sg_set_buf(&sg[1], buf + sg[0].length, buflen - sg[0].length); |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 725 | nsg++; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 726 | } |
| 727 | |
Jens Axboe | c46f233 | 2007-10-31 12:06:37 +0100 | [diff] [blame] | 728 | sg_mark_end(&sg[nsg - 1]); |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 729 | |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 730 | ASSERTCMP(sg[0].length + sg[1].length, ==, buflen); |
| 731 | } |
| 732 | |
| 733 | /* |
| 734 | * encrypt the response packet |
| 735 | */ |
| 736 | static void rxkad_encrypt_response(struct rxrpc_connection *conn, |
| 737 | struct rxkad_response *resp, |
| 738 | const struct rxkad_key *s2) |
| 739 | { |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 740 | SKCIPHER_REQUEST_ON_STACK(req, conn->cipher); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 741 | struct rxrpc_crypt iv; |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 742 | struct scatterlist sg[2]; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 743 | |
| 744 | /* continue encrypting from where we left off */ |
| 745 | memcpy(&iv, s2->session_key, sizeof(iv)); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 746 | |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 747 | rxkad_sg_set_buf2(sg, &resp->encrypted, sizeof(resp->encrypted)); |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 748 | |
| 749 | skcipher_request_set_tfm(req, conn->cipher); |
| 750 | skcipher_request_set_callback(req, 0, NULL, NULL); |
| 751 | skcipher_request_set_crypt(req, sg, sg, sizeof(resp->encrypted), iv.x); |
| 752 | |
| 753 | crypto_skcipher_encrypt(req); |
| 754 | skcipher_request_zero(req); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 755 | } |
| 756 | |
| 757 | /* |
| 758 | * respond to a challenge packet |
| 759 | */ |
| 760 | static int rxkad_respond_to_challenge(struct rxrpc_connection *conn, |
| 761 | struct sk_buff *skb, |
| 762 | u32 *_abort_code) |
| 763 | { |
David Howells | 3394128 | 2009-09-14 01:17:35 +0000 | [diff] [blame] | 764 | const struct rxrpc_key_token *token; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 765 | struct rxkad_challenge challenge; |
| 766 | struct rxkad_response resp |
| 767 | __attribute__((aligned(8))); /* must be aligned for crypto */ |
| 768 | struct rxrpc_skb_priv *sp; |
| 769 | u32 version, nonce, min_level, abort_code; |
| 770 | int ret; |
| 771 | |
| 772 | _enter("{%d,%x}", conn->debug_id, key_serial(conn->key)); |
| 773 | |
| 774 | if (!conn->key) { |
| 775 | _leave(" = -EPROTO [no key]"); |
| 776 | return -EPROTO; |
| 777 | } |
| 778 | |
| 779 | ret = key_validate(conn->key); |
| 780 | if (ret < 0) { |
| 781 | *_abort_code = RXKADEXPIRED; |
| 782 | return ret; |
| 783 | } |
| 784 | |
| 785 | abort_code = RXKADPACKETSHORT; |
| 786 | sp = rxrpc_skb(skb); |
| 787 | if (skb_copy_bits(skb, 0, &challenge, sizeof(challenge)) < 0) |
| 788 | goto protocol_error; |
| 789 | |
| 790 | version = ntohl(challenge.version); |
| 791 | nonce = ntohl(challenge.nonce); |
| 792 | min_level = ntohl(challenge.min_level); |
| 793 | |
| 794 | _proto("Rx CHALLENGE %%%u { v=%u n=%u ml=%u }", |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 795 | sp->hdr.serial, version, nonce, min_level); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 796 | |
| 797 | abort_code = RXKADINCONSISTENCY; |
| 798 | if (version != RXKAD_VERSION) |
| 799 | goto protocol_error; |
| 800 | |
| 801 | abort_code = RXKADLEVELFAIL; |
| 802 | if (conn->security_level < min_level) |
| 803 | goto protocol_error; |
| 804 | |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 805 | token = conn->key->payload.data[0]; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 806 | |
| 807 | /* build the response packet */ |
| 808 | memset(&resp, 0, sizeof(resp)); |
| 809 | |
David Howells | 098a209 | 2016-03-04 15:59:00 +0000 | [diff] [blame] | 810 | resp.version = htonl(RXKAD_VERSION); |
| 811 | resp.encrypted.epoch = htonl(conn->epoch); |
| 812 | resp.encrypted.cid = htonl(conn->cid); |
| 813 | resp.encrypted.securityIndex = htonl(conn->security_ix); |
| 814 | resp.encrypted.inc_nonce = htonl(nonce + 1); |
| 815 | resp.encrypted.level = htonl(conn->security_level); |
| 816 | resp.kvno = htonl(token->kad->kvno); |
| 817 | resp.ticket_len = htonl(token->kad->ticket_len); |
| 818 | |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 819 | resp.encrypted.call_id[0] = |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 820 | htonl(conn->channels[0] ? conn->channels[0]->call_id : 0); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 821 | resp.encrypted.call_id[1] = |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 822 | htonl(conn->channels[1] ? conn->channels[1]->call_id : 0); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 823 | resp.encrypted.call_id[2] = |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 824 | htonl(conn->channels[2] ? conn->channels[2]->call_id : 0); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 825 | resp.encrypted.call_id[3] = |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 826 | htonl(conn->channels[3] ? conn->channels[3]->call_id : 0); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 827 | |
| 828 | /* calculate the response checksum and then do the encryption */ |
| 829 | rxkad_calc_response_checksum(&resp); |
David Howells | 3394128 | 2009-09-14 01:17:35 +0000 | [diff] [blame] | 830 | rxkad_encrypt_response(conn, &resp, token->kad); |
| 831 | return rxkad_send_response(conn, &sp->hdr, &resp, token->kad); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 832 | |
| 833 | protocol_error: |
| 834 | *_abort_code = abort_code; |
| 835 | _leave(" = -EPROTO [%d]", abort_code); |
| 836 | return -EPROTO; |
| 837 | } |
| 838 | |
| 839 | /* |
| 840 | * decrypt the kerberos IV ticket in the response |
| 841 | */ |
| 842 | static int rxkad_decrypt_ticket(struct rxrpc_connection *conn, |
| 843 | void *ticket, size_t ticket_len, |
| 844 | struct rxrpc_crypt *_session_key, |
| 845 | time_t *_expiry, |
| 846 | u32 *_abort_code) |
| 847 | { |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 848 | struct skcipher_request *req; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 849 | struct rxrpc_crypt iv, key; |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 850 | struct scatterlist sg[1]; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 851 | struct in_addr addr; |
Eric Dumazet | 95c9617 | 2012-04-15 05:58:06 +0000 | [diff] [blame] | 852 | unsigned int life; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 853 | time_t issue, now; |
| 854 | bool little_endian; |
| 855 | int ret; |
| 856 | u8 *p, *q, *name, *end; |
| 857 | |
| 858 | _enter("{%d},{%x}", conn->debug_id, key_serial(conn->server_key)); |
| 859 | |
| 860 | *_expiry = 0; |
| 861 | |
| 862 | ret = key_validate(conn->server_key); |
| 863 | if (ret < 0) { |
| 864 | switch (ret) { |
| 865 | case -EKEYEXPIRED: |
| 866 | *_abort_code = RXKADEXPIRED; |
| 867 | goto error; |
| 868 | default: |
| 869 | *_abort_code = RXKADNOAUTH; |
| 870 | goto error; |
| 871 | } |
| 872 | } |
| 873 | |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 874 | ASSERT(conn->server_key->payload.data[0] != NULL); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 875 | ASSERTCMP((unsigned long) ticket & 7UL, ==, 0); |
| 876 | |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 877 | memcpy(&iv, &conn->server_key->payload.data[2], sizeof(iv)); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 878 | |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 879 | req = skcipher_request_alloc(conn->server_key->payload.data[0], |
| 880 | GFP_NOFS); |
| 881 | if (!req) { |
| 882 | *_abort_code = RXKADNOAUTH; |
| 883 | ret = -ENOMEM; |
| 884 | goto error; |
| 885 | } |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 886 | |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 887 | sg_init_one(&sg[0], ticket, ticket_len); |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 888 | |
| 889 | skcipher_request_set_callback(req, 0, NULL, NULL); |
| 890 | skcipher_request_set_crypt(req, sg, sg, ticket_len, iv.x); |
| 891 | |
| 892 | crypto_skcipher_decrypt(req); |
| 893 | skcipher_request_free(req); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 894 | |
| 895 | p = ticket; |
| 896 | end = p + ticket_len; |
| 897 | |
| 898 | #define Z(size) \ |
| 899 | ({ \ |
| 900 | u8 *__str = p; \ |
| 901 | q = memchr(p, 0, end - p); \ |
| 902 | if (!q || q - p > (size)) \ |
| 903 | goto bad_ticket; \ |
| 904 | for (; p < q; p++) \ |
| 905 | if (!isprint(*p)) \ |
| 906 | goto bad_ticket; \ |
| 907 | p++; \ |
| 908 | __str; \ |
| 909 | }) |
| 910 | |
| 911 | /* extract the ticket flags */ |
| 912 | _debug("KIV FLAGS: %x", *p); |
| 913 | little_endian = *p & 1; |
| 914 | p++; |
| 915 | |
| 916 | /* extract the authentication name */ |
| 917 | name = Z(ANAME_SZ); |
| 918 | _debug("KIV ANAME: %s", name); |
| 919 | |
| 920 | /* extract the principal's instance */ |
| 921 | name = Z(INST_SZ); |
| 922 | _debug("KIV INST : %s", name); |
| 923 | |
| 924 | /* extract the principal's authentication domain */ |
| 925 | name = Z(REALM_SZ); |
| 926 | _debug("KIV REALM: %s", name); |
| 927 | |
| 928 | if (end - p < 4 + 8 + 4 + 2) |
| 929 | goto bad_ticket; |
| 930 | |
| 931 | /* get the IPv4 address of the entity that requested the ticket */ |
| 932 | memcpy(&addr, p, sizeof(addr)); |
| 933 | p += 4; |
Harvey Harrison | 21454aa | 2008-10-31 00:54:56 -0700 | [diff] [blame] | 934 | _debug("KIV ADDR : %pI4", &addr); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 935 | |
| 936 | /* get the session key from the ticket */ |
| 937 | memcpy(&key, p, sizeof(key)); |
| 938 | p += 8; |
| 939 | _debug("KIV KEY : %08x %08x", ntohl(key.n[0]), ntohl(key.n[1])); |
| 940 | memcpy(_session_key, &key, sizeof(key)); |
| 941 | |
| 942 | /* get the ticket's lifetime */ |
| 943 | life = *p++ * 5 * 60; |
| 944 | _debug("KIV LIFE : %u", life); |
| 945 | |
| 946 | /* get the issue time of the ticket */ |
| 947 | if (little_endian) { |
| 948 | __le32 stamp; |
| 949 | memcpy(&stamp, p, 4); |
| 950 | issue = le32_to_cpu(stamp); |
| 951 | } else { |
| 952 | __be32 stamp; |
| 953 | memcpy(&stamp, p, 4); |
| 954 | issue = be32_to_cpu(stamp); |
| 955 | } |
| 956 | p += 4; |
john stultz | 2c6b47d | 2007-07-24 17:47:43 -0700 | [diff] [blame] | 957 | now = get_seconds(); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 958 | _debug("KIV ISSUE: %lx [%lx]", issue, now); |
| 959 | |
| 960 | /* check the ticket is in date */ |
| 961 | if (issue > now) { |
| 962 | *_abort_code = RXKADNOAUTH; |
| 963 | ret = -EKEYREJECTED; |
| 964 | goto error; |
| 965 | } |
| 966 | |
| 967 | if (issue < now - life) { |
| 968 | *_abort_code = RXKADEXPIRED; |
| 969 | ret = -EKEYEXPIRED; |
| 970 | goto error; |
| 971 | } |
| 972 | |
| 973 | *_expiry = issue + life; |
| 974 | |
| 975 | /* get the service name */ |
| 976 | name = Z(SNAME_SZ); |
| 977 | _debug("KIV SNAME: %s", name); |
| 978 | |
| 979 | /* get the service instance name */ |
| 980 | name = Z(INST_SZ); |
| 981 | _debug("KIV SINST: %s", name); |
| 982 | |
| 983 | ret = 0; |
| 984 | error: |
| 985 | _leave(" = %d", ret); |
| 986 | return ret; |
| 987 | |
| 988 | bad_ticket: |
| 989 | *_abort_code = RXKADBADTICKET; |
| 990 | ret = -EBADMSG; |
| 991 | goto error; |
| 992 | } |
| 993 | |
| 994 | /* |
| 995 | * decrypt the response packet |
| 996 | */ |
| 997 | static void rxkad_decrypt_response(struct rxrpc_connection *conn, |
| 998 | struct rxkad_response *resp, |
| 999 | const struct rxrpc_crypt *session_key) |
| 1000 | { |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 1001 | SKCIPHER_REQUEST_ON_STACK(req, rxkad_ci); |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 1002 | struct scatterlist sg[2]; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1003 | struct rxrpc_crypt iv; |
| 1004 | |
| 1005 | _enter(",,%08x%08x", |
| 1006 | ntohl(session_key->n[0]), ntohl(session_key->n[1])); |
| 1007 | |
| 1008 | ASSERT(rxkad_ci != NULL); |
| 1009 | |
| 1010 | mutex_lock(&rxkad_ci_mutex); |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 1011 | if (crypto_skcipher_setkey(rxkad_ci, session_key->x, |
| 1012 | sizeof(*session_key)) < 0) |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1013 | BUG(); |
| 1014 | |
| 1015 | memcpy(&iv, session_key, sizeof(iv)); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1016 | |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 1017 | rxkad_sg_set_buf2(sg, &resp->encrypted, sizeof(resp->encrypted)); |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 1018 | |
| 1019 | skcipher_request_set_tfm(req, rxkad_ci); |
| 1020 | skcipher_request_set_callback(req, 0, NULL, NULL); |
| 1021 | skcipher_request_set_crypt(req, sg, sg, sizeof(resp->encrypted), iv.x); |
| 1022 | |
| 1023 | crypto_skcipher_decrypt(req); |
| 1024 | skcipher_request_zero(req); |
| 1025 | |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1026 | mutex_unlock(&rxkad_ci_mutex); |
| 1027 | |
| 1028 | _leave(""); |
| 1029 | } |
| 1030 | |
| 1031 | /* |
| 1032 | * verify a response |
| 1033 | */ |
| 1034 | static int rxkad_verify_response(struct rxrpc_connection *conn, |
| 1035 | struct sk_buff *skb, |
| 1036 | u32 *_abort_code) |
| 1037 | { |
| 1038 | struct rxkad_response response |
| 1039 | __attribute__((aligned(8))); /* must be aligned for crypto */ |
| 1040 | struct rxrpc_skb_priv *sp; |
| 1041 | struct rxrpc_crypt session_key; |
| 1042 | time_t expiry; |
| 1043 | void *ticket; |
Al Viro | 91e916c | 2008-03-29 03:08:38 +0000 | [diff] [blame] | 1044 | u32 abort_code, version, kvno, ticket_len, level; |
| 1045 | __be32 csum; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1046 | int ret; |
| 1047 | |
| 1048 | _enter("{%d,%x}", conn->debug_id, key_serial(conn->server_key)); |
| 1049 | |
| 1050 | abort_code = RXKADPACKETSHORT; |
| 1051 | if (skb_copy_bits(skb, 0, &response, sizeof(response)) < 0) |
| 1052 | goto protocol_error; |
| 1053 | if (!pskb_pull(skb, sizeof(response))) |
| 1054 | BUG(); |
| 1055 | |
| 1056 | version = ntohl(response.version); |
| 1057 | ticket_len = ntohl(response.ticket_len); |
| 1058 | kvno = ntohl(response.kvno); |
| 1059 | sp = rxrpc_skb(skb); |
| 1060 | _proto("Rx RESPONSE %%%u { v=%u kv=%u tl=%u }", |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 1061 | sp->hdr.serial, version, kvno, ticket_len); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1062 | |
| 1063 | abort_code = RXKADINCONSISTENCY; |
| 1064 | if (version != RXKAD_VERSION) |
David Howells | 4aa9cb3 | 2007-12-07 04:31:47 -0800 | [diff] [blame] | 1065 | goto protocol_error; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1066 | |
| 1067 | abort_code = RXKADTICKETLEN; |
| 1068 | if (ticket_len < 4 || ticket_len > MAXKRB5TICKETLEN) |
| 1069 | goto protocol_error; |
| 1070 | |
| 1071 | abort_code = RXKADUNKNOWNKEY; |
| 1072 | if (kvno >= RXKAD_TKT_TYPE_KERBEROS_V5) |
| 1073 | goto protocol_error; |
| 1074 | |
| 1075 | /* extract the kerberos ticket and decrypt and decode it */ |
| 1076 | ticket = kmalloc(ticket_len, GFP_NOFS); |
| 1077 | if (!ticket) |
| 1078 | return -ENOMEM; |
| 1079 | |
| 1080 | abort_code = RXKADPACKETSHORT; |
| 1081 | if (skb_copy_bits(skb, 0, ticket, ticket_len) < 0) |
| 1082 | goto protocol_error_free; |
| 1083 | |
| 1084 | ret = rxkad_decrypt_ticket(conn, ticket, ticket_len, &session_key, |
| 1085 | &expiry, &abort_code); |
| 1086 | if (ret < 0) { |
| 1087 | *_abort_code = abort_code; |
| 1088 | kfree(ticket); |
| 1089 | return ret; |
| 1090 | } |
| 1091 | |
| 1092 | /* use the session key from inside the ticket to decrypt the |
| 1093 | * response */ |
| 1094 | rxkad_decrypt_response(conn, &response, &session_key); |
| 1095 | |
| 1096 | abort_code = RXKADSEALEDINCON; |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 1097 | if (ntohl(response.encrypted.epoch) != conn->epoch) |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1098 | goto protocol_error_free; |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 1099 | if (ntohl(response.encrypted.cid) != conn->cid) |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1100 | goto protocol_error_free; |
| 1101 | if (ntohl(response.encrypted.securityIndex) != conn->security_ix) |
| 1102 | goto protocol_error_free; |
| 1103 | csum = response.encrypted.checksum; |
| 1104 | response.encrypted.checksum = 0; |
| 1105 | rxkad_calc_response_checksum(&response); |
| 1106 | if (response.encrypted.checksum != csum) |
| 1107 | goto protocol_error_free; |
| 1108 | |
| 1109 | if (ntohl(response.encrypted.call_id[0]) > INT_MAX || |
| 1110 | ntohl(response.encrypted.call_id[1]) > INT_MAX || |
| 1111 | ntohl(response.encrypted.call_id[2]) > INT_MAX || |
| 1112 | ntohl(response.encrypted.call_id[3]) > INT_MAX) |
| 1113 | goto protocol_error_free; |
| 1114 | |
| 1115 | abort_code = RXKADOUTOFSEQUENCE; |
David Howells | 0d12f8a | 2016-03-04 15:53:46 +0000 | [diff] [blame] | 1116 | if (ntohl(response.encrypted.inc_nonce) != conn->security_nonce + 1) |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1117 | goto protocol_error_free; |
| 1118 | |
| 1119 | abort_code = RXKADLEVELFAIL; |
| 1120 | level = ntohl(response.encrypted.level); |
| 1121 | if (level > RXRPC_SECURITY_ENCRYPT) |
| 1122 | goto protocol_error_free; |
| 1123 | conn->security_level = level; |
| 1124 | |
| 1125 | /* create a key to hold the security data and expiration time - after |
| 1126 | * this the connection security can be handled in exactly the same way |
| 1127 | * as for a client connection */ |
| 1128 | ret = rxrpc_get_server_data_key(conn, &session_key, expiry, kvno); |
| 1129 | if (ret < 0) { |
| 1130 | kfree(ticket); |
| 1131 | return ret; |
| 1132 | } |
| 1133 | |
| 1134 | kfree(ticket); |
| 1135 | _leave(" = 0"); |
| 1136 | return 0; |
| 1137 | |
| 1138 | protocol_error_free: |
| 1139 | kfree(ticket); |
| 1140 | protocol_error: |
| 1141 | *_abort_code = abort_code; |
| 1142 | _leave(" = -EPROTO [%d]", abort_code); |
| 1143 | return -EPROTO; |
| 1144 | } |
| 1145 | |
| 1146 | /* |
| 1147 | * clear the connection security |
| 1148 | */ |
| 1149 | static void rxkad_clear(struct rxrpc_connection *conn) |
| 1150 | { |
| 1151 | _enter(""); |
| 1152 | |
| 1153 | if (conn->cipher) |
Herbert Xu | 1afe593 | 2016-01-24 21:19:01 +0800 | [diff] [blame] | 1154 | crypto_free_skcipher(conn->cipher); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1155 | } |
| 1156 | |
| 1157 | /* |
David Howells | 648af7f | 2016-04-07 17:23:51 +0100 | [diff] [blame] | 1158 | * Initialise the rxkad security service. |
| 1159 | */ |
| 1160 | static int rxkad_init(void) |
| 1161 | { |
| 1162 | /* pin the cipher we need so that the crypto layer doesn't invoke |
| 1163 | * keventd to go get it */ |
| 1164 | rxkad_ci = crypto_alloc_skcipher("pcbc(fcrypt)", 0, CRYPTO_ALG_ASYNC); |
Wu Fengguang | fa54cc7 | 2016-06-05 07:17:19 +0800 | [diff] [blame^] | 1165 | return PTR_ERR_OR_ZERO(rxkad_ci); |
David Howells | 648af7f | 2016-04-07 17:23:51 +0100 | [diff] [blame] | 1166 | } |
| 1167 | |
| 1168 | /* |
| 1169 | * Clean up the rxkad security service. |
| 1170 | */ |
| 1171 | static void rxkad_exit(void) |
| 1172 | { |
| 1173 | if (rxkad_ci) |
| 1174 | crypto_free_skcipher(rxkad_ci); |
| 1175 | } |
| 1176 | |
| 1177 | /* |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1178 | * RxRPC Kerberos-based security |
| 1179 | */ |
David Howells | 648af7f | 2016-04-07 17:23:51 +0100 | [diff] [blame] | 1180 | const struct rxrpc_security rxkad = { |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1181 | .name = "rxkad", |
David Howells | 8b81547 | 2009-09-14 01:17:30 +0000 | [diff] [blame] | 1182 | .security_index = RXRPC_SECURITY_RXKAD, |
David Howells | 648af7f | 2016-04-07 17:23:51 +0100 | [diff] [blame] | 1183 | .init = rxkad_init, |
| 1184 | .exit = rxkad_exit, |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1185 | .init_connection_security = rxkad_init_connection_security, |
| 1186 | .prime_packet_security = rxkad_prime_packet_security, |
| 1187 | .secure_packet = rxkad_secure_packet, |
| 1188 | .verify_packet = rxkad_verify_packet, |
| 1189 | .issue_challenge = rxkad_issue_challenge, |
| 1190 | .respond_to_challenge = rxkad_respond_to_challenge, |
| 1191 | .verify_response = rxkad_verify_response, |
| 1192 | .clear = rxkad_clear, |
| 1193 | }; |