1237fead6SMichael Halcrow /** 2237fead6SMichael Halcrow * eCryptfs: Linux filesystem encryption layer 3237fead6SMichael Halcrow * In-kernel key management code. Includes functions to parse and 4237fead6SMichael Halcrow * write authentication token-related packets with the underlying 5237fead6SMichael Halcrow * file. 6237fead6SMichael Halcrow * 7237fead6SMichael Halcrow * Copyright (C) 2004-2006 International Business Machines Corp. 8237fead6SMichael Halcrow * Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com> 9237fead6SMichael Halcrow * Michael C. Thompson <mcthomps@us.ibm.com> 10237fead6SMichael Halcrow * 11237fead6SMichael Halcrow * This program is free software; you can redistribute it and/or 12237fead6SMichael Halcrow * modify it under the terms of the GNU General Public License as 13237fead6SMichael Halcrow * published by the Free Software Foundation; either version 2 of the 14237fead6SMichael Halcrow * License, or (at your option) any later version. 15237fead6SMichael Halcrow * 16237fead6SMichael Halcrow * This program is distributed in the hope that it will be useful, but 17237fead6SMichael Halcrow * WITHOUT ANY WARRANTY; without even the implied warranty of 18237fead6SMichael Halcrow * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 19237fead6SMichael Halcrow * General Public License for more details. 20237fead6SMichael Halcrow * 21237fead6SMichael Halcrow * You should have received a copy of the GNU General Public License 22237fead6SMichael Halcrow * along with this program; if not, write to the Free Software 23237fead6SMichael Halcrow * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 24237fead6SMichael Halcrow * 02111-1307, USA. 25237fead6SMichael Halcrow */ 26237fead6SMichael Halcrow 27237fead6SMichael Halcrow #include <linux/string.h> 28237fead6SMichael Halcrow #include <linux/sched.h> 29237fead6SMichael Halcrow #include <linux/syscalls.h> 30237fead6SMichael Halcrow #include <linux/pagemap.h> 31237fead6SMichael Halcrow #include <linux/key.h> 32237fead6SMichael Halcrow #include <linux/random.h> 33237fead6SMichael Halcrow #include <linux/crypto.h> 34237fead6SMichael Halcrow #include <linux/scatterlist.h> 35237fead6SMichael Halcrow #include "ecryptfs_kernel.h" 36237fead6SMichael Halcrow 37237fead6SMichael Halcrow /** 38237fead6SMichael Halcrow * request_key returned an error instead of a valid key address; 39237fead6SMichael Halcrow * determine the type of error, make appropriate log entries, and 40237fead6SMichael Halcrow * return an error code. 41237fead6SMichael Halcrow */ 42237fead6SMichael Halcrow int process_request_key_err(long err_code) 43237fead6SMichael Halcrow { 44237fead6SMichael Halcrow int rc = 0; 45237fead6SMichael Halcrow 46237fead6SMichael Halcrow switch (err_code) { 47237fead6SMichael Halcrow case ENOKEY: 48237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "No key\n"); 49237fead6SMichael Halcrow rc = -ENOENT; 50237fead6SMichael Halcrow break; 51237fead6SMichael Halcrow case EKEYEXPIRED: 52237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Key expired\n"); 53237fead6SMichael Halcrow rc = -ETIME; 54237fead6SMichael Halcrow break; 55237fead6SMichael Halcrow case EKEYREVOKED: 56237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Key revoked\n"); 57237fead6SMichael Halcrow rc = -EINVAL; 58237fead6SMichael Halcrow break; 59237fead6SMichael Halcrow default: 60237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Unknown error code: " 61237fead6SMichael Halcrow "[0x%.16x]\n", err_code); 62237fead6SMichael Halcrow rc = -EINVAL; 63237fead6SMichael Halcrow } 64237fead6SMichael Halcrow return rc; 65237fead6SMichael Halcrow } 66237fead6SMichael Halcrow 67237fead6SMichael Halcrow static void wipe_auth_tok_list(struct list_head *auth_tok_list_head) 68237fead6SMichael Halcrow { 69237fead6SMichael Halcrow struct list_head *walker; 70237fead6SMichael Halcrow struct ecryptfs_auth_tok_list_item *auth_tok_list_item; 71237fead6SMichael Halcrow 72237fead6SMichael Halcrow walker = auth_tok_list_head->next; 73237fead6SMichael Halcrow while (walker != auth_tok_list_head) { 74237fead6SMichael Halcrow auth_tok_list_item = 75237fead6SMichael Halcrow list_entry(walker, struct ecryptfs_auth_tok_list_item, 76237fead6SMichael Halcrow list); 77237fead6SMichael Halcrow walker = auth_tok_list_item->list.next; 78237fead6SMichael Halcrow memset(auth_tok_list_item, 0, 79237fead6SMichael Halcrow sizeof(struct ecryptfs_auth_tok_list_item)); 80237fead6SMichael Halcrow kmem_cache_free(ecryptfs_auth_tok_list_item_cache, 81237fead6SMichael Halcrow auth_tok_list_item); 82237fead6SMichael Halcrow } 83237fead6SMichael Halcrow } 84237fead6SMichael Halcrow 85237fead6SMichael Halcrow struct kmem_cache *ecryptfs_auth_tok_list_item_cache; 86237fead6SMichael Halcrow 87237fead6SMichael Halcrow /** 88237fead6SMichael Halcrow * parse_packet_length 89237fead6SMichael Halcrow * @data: Pointer to memory containing length at offset 90237fead6SMichael Halcrow * @size: This function writes the decoded size to this memory 91237fead6SMichael Halcrow * address; zero on error 92237fead6SMichael Halcrow * @length_size: The number of bytes occupied by the encoded length 93237fead6SMichael Halcrow * 94237fead6SMichael Halcrow * Returns Zero on success 95237fead6SMichael Halcrow */ 96237fead6SMichael Halcrow static int parse_packet_length(unsigned char *data, size_t *size, 97237fead6SMichael Halcrow size_t *length_size) 98237fead6SMichael Halcrow { 99237fead6SMichael Halcrow int rc = 0; 100237fead6SMichael Halcrow 101237fead6SMichael Halcrow (*length_size) = 0; 102237fead6SMichael Halcrow (*size) = 0; 103237fead6SMichael Halcrow if (data[0] < 192) { 104237fead6SMichael Halcrow /* One-byte length */ 105237fead6SMichael Halcrow (*size) = data[0]; 106237fead6SMichael Halcrow (*length_size) = 1; 107237fead6SMichael Halcrow } else if (data[0] < 224) { 108237fead6SMichael Halcrow /* Two-byte length */ 109237fead6SMichael Halcrow (*size) = ((data[0] - 192) * 256); 110237fead6SMichael Halcrow (*size) += (data[1] + 192); 111237fead6SMichael Halcrow (*length_size) = 2; 112237fead6SMichael Halcrow } else if (data[0] == 255) { 113237fead6SMichael Halcrow /* Five-byte length; we're not supposed to see this */ 114237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Five-byte packet length not " 115237fead6SMichael Halcrow "supported\n"); 116237fead6SMichael Halcrow rc = -EINVAL; 117237fead6SMichael Halcrow goto out; 118237fead6SMichael Halcrow } else { 119237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error parsing packet length\n"); 120237fead6SMichael Halcrow rc = -EINVAL; 121237fead6SMichael Halcrow goto out; 122237fead6SMichael Halcrow } 123237fead6SMichael Halcrow out: 124237fead6SMichael Halcrow return rc; 125237fead6SMichael Halcrow } 126237fead6SMichael Halcrow 127237fead6SMichael Halcrow /** 128237fead6SMichael Halcrow * write_packet_length 129237fead6SMichael Halcrow * @dest: The byte array target into which to write the 130237fead6SMichael Halcrow * length. Must have at least 5 bytes allocated. 131237fead6SMichael Halcrow * @size: The length to write. 132237fead6SMichael Halcrow * @packet_size_length: The number of bytes used to encode the 133237fead6SMichael Halcrow * packet length is written to this address. 134237fead6SMichael Halcrow * 135237fead6SMichael Halcrow * Returns zero on success; non-zero on error. 136237fead6SMichael Halcrow */ 137237fead6SMichael Halcrow static int write_packet_length(char *dest, size_t size, 138237fead6SMichael Halcrow size_t *packet_size_length) 139237fead6SMichael Halcrow { 140237fead6SMichael Halcrow int rc = 0; 141237fead6SMichael Halcrow 142237fead6SMichael Halcrow if (size < 192) { 143237fead6SMichael Halcrow dest[0] = size; 144237fead6SMichael Halcrow (*packet_size_length) = 1; 145237fead6SMichael Halcrow } else if (size < 65536) { 146237fead6SMichael Halcrow dest[0] = (((size - 192) / 256) + 192); 147237fead6SMichael Halcrow dest[1] = ((size - 192) % 256); 148237fead6SMichael Halcrow (*packet_size_length) = 2; 149237fead6SMichael Halcrow } else { 150237fead6SMichael Halcrow rc = -EINVAL; 151237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, 152237fead6SMichael Halcrow "Unsupported packet size: [%d]\n", size); 153237fead6SMichael Halcrow } 154237fead6SMichael Halcrow return rc; 155237fead6SMichael Halcrow } 156237fead6SMichael Halcrow 157237fead6SMichael Halcrow /** 158237fead6SMichael Halcrow * parse_tag_3_packet 159237fead6SMichael Halcrow * @crypt_stat: The cryptographic context to modify based on packet 160237fead6SMichael Halcrow * contents. 161237fead6SMichael Halcrow * @data: The raw bytes of the packet. 162237fead6SMichael Halcrow * @auth_tok_list: eCryptfs parses packets into authentication tokens; 163237fead6SMichael Halcrow * a new authentication token will be placed at the end 164237fead6SMichael Halcrow * of this list for this packet. 165237fead6SMichael Halcrow * @new_auth_tok: Pointer to a pointer to memory that this function 166237fead6SMichael Halcrow * allocates; sets the memory address of the pointer to 167237fead6SMichael Halcrow * NULL on error. This object is added to the 168237fead6SMichael Halcrow * auth_tok_list. 169237fead6SMichael Halcrow * @packet_size: This function writes the size of the parsed packet 170237fead6SMichael Halcrow * into this memory location; zero on error. 171237fead6SMichael Halcrow * @max_packet_size: maximum number of bytes to parse 172237fead6SMichael Halcrow * 173237fead6SMichael Halcrow * Returns zero on success; non-zero on error. 174237fead6SMichael Halcrow */ 175237fead6SMichael Halcrow static int 176237fead6SMichael Halcrow parse_tag_3_packet(struct ecryptfs_crypt_stat *crypt_stat, 177237fead6SMichael Halcrow unsigned char *data, struct list_head *auth_tok_list, 178237fead6SMichael Halcrow struct ecryptfs_auth_tok **new_auth_tok, 179237fead6SMichael Halcrow size_t *packet_size, size_t max_packet_size) 180237fead6SMichael Halcrow { 181237fead6SMichael Halcrow int rc = 0; 182237fead6SMichael Halcrow size_t body_size; 183237fead6SMichael Halcrow struct ecryptfs_auth_tok_list_item *auth_tok_list_item; 184237fead6SMichael Halcrow size_t length_size; 185237fead6SMichael Halcrow 186237fead6SMichael Halcrow (*packet_size) = 0; 187237fead6SMichael Halcrow (*new_auth_tok) = NULL; 188237fead6SMichael Halcrow 189237fead6SMichael Halcrow /* we check that: 190237fead6SMichael Halcrow * one byte for the Tag 3 ID flag 191237fead6SMichael Halcrow * two bytes for the body size 192237fead6SMichael Halcrow * do not exceed the maximum_packet_size 193237fead6SMichael Halcrow */ 194237fead6SMichael Halcrow if (unlikely((*packet_size) + 3 > max_packet_size)) { 195237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Packet size exceeds max\n"); 196237fead6SMichael Halcrow rc = -EINVAL; 197237fead6SMichael Halcrow goto out; 198237fead6SMichael Halcrow } 199237fead6SMichael Halcrow 200237fead6SMichael Halcrow /* check for Tag 3 identifyer - one byte */ 201237fead6SMichael Halcrow if (data[(*packet_size)++] != ECRYPTFS_TAG_3_PACKET_TYPE) { 202237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Enter w/ first byte != 0x%.2x\n", 203237fead6SMichael Halcrow ECRYPTFS_TAG_3_PACKET_TYPE); 204237fead6SMichael Halcrow rc = -EINVAL; 205237fead6SMichael Halcrow goto out; 206237fead6SMichael Halcrow } 207237fead6SMichael Halcrow /* Released: wipe_auth_tok_list called in ecryptfs_parse_packet_set or 208237fead6SMichael Halcrow * at end of function upon failure */ 209237fead6SMichael Halcrow auth_tok_list_item = 210c3762229SRobert P. J. Day kmem_cache_zalloc(ecryptfs_auth_tok_list_item_cache, GFP_KERNEL); 211237fead6SMichael Halcrow if (!auth_tok_list_item) { 212237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Unable to allocate memory\n"); 213237fead6SMichael Halcrow rc = -ENOMEM; 214237fead6SMichael Halcrow goto out; 215237fead6SMichael Halcrow } 216237fead6SMichael Halcrow (*new_auth_tok) = &auth_tok_list_item->auth_tok; 217237fead6SMichael Halcrow 218237fead6SMichael Halcrow /* check for body size - one to two bytes */ 219237fead6SMichael Halcrow rc = parse_packet_length(&data[(*packet_size)], &body_size, 220237fead6SMichael Halcrow &length_size); 221237fead6SMichael Halcrow if (rc) { 222237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Error parsing packet length; " 223237fead6SMichael Halcrow "rc = [%d]\n", rc); 224237fead6SMichael Halcrow goto out_free; 225237fead6SMichael Halcrow } 226237fead6SMichael Halcrow if (unlikely(body_size < (0x05 + ECRYPTFS_SALT_SIZE))) { 227237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Invalid body size ([%d])\n", 228237fead6SMichael Halcrow body_size); 229237fead6SMichael Halcrow rc = -EINVAL; 230237fead6SMichael Halcrow goto out_free; 231237fead6SMichael Halcrow } 232237fead6SMichael Halcrow (*packet_size) += length_size; 233237fead6SMichael Halcrow 234237fead6SMichael Halcrow /* now we know the length of the remainting Tag 3 packet size: 235237fead6SMichael Halcrow * 5 fix bytes for: version string, cipher, S2K ID, hash algo, 236237fead6SMichael Halcrow * number of hash iterations 237237fead6SMichael Halcrow * ECRYPTFS_SALT_SIZE bytes for salt 238237fead6SMichael Halcrow * body_size bytes minus the stuff above is the encrypted key size 239237fead6SMichael Halcrow */ 240237fead6SMichael Halcrow if (unlikely((*packet_size) + body_size > max_packet_size)) { 241237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Packet size exceeds max\n"); 242237fead6SMichael Halcrow rc = -EINVAL; 243237fead6SMichael Halcrow goto out_free; 244237fead6SMichael Halcrow } 245237fead6SMichael Halcrow 246237fead6SMichael Halcrow /* There are 5 characters of additional information in the 247237fead6SMichael Halcrow * packet */ 248237fead6SMichael Halcrow (*new_auth_tok)->session_key.encrypted_key_size = 249237fead6SMichael Halcrow body_size - (0x05 + ECRYPTFS_SALT_SIZE); 250237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Encrypted key size = [%d]\n", 251237fead6SMichael Halcrow (*new_auth_tok)->session_key.encrypted_key_size); 252237fead6SMichael Halcrow 253237fead6SMichael Halcrow /* Version 4 (from RFC2440) - one byte */ 254237fead6SMichael Halcrow if (unlikely(data[(*packet_size)++] != 0x04)) { 255237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Unknown version number " 256237fead6SMichael Halcrow "[%d]\n", data[(*packet_size) - 1]); 257237fead6SMichael Halcrow rc = -EINVAL; 258237fead6SMichael Halcrow goto out_free; 259237fead6SMichael Halcrow } 260237fead6SMichael Halcrow 261237fead6SMichael Halcrow /* cipher - one byte */ 262237fead6SMichael Halcrow ecryptfs_cipher_code_to_string(crypt_stat->cipher, 263237fead6SMichael Halcrow (u16)data[(*packet_size)]); 264237fead6SMichael Halcrow /* A little extra work to differentiate among the AES key 265237fead6SMichael Halcrow * sizes; see RFC2440 */ 266237fead6SMichael Halcrow switch(data[(*packet_size)++]) { 267237fead6SMichael Halcrow case RFC2440_CIPHER_AES_192: 268237fead6SMichael Halcrow crypt_stat->key_size = 24; 269237fead6SMichael Halcrow break; 270237fead6SMichael Halcrow default: 271237fead6SMichael Halcrow crypt_stat->key_size = 272237fead6SMichael Halcrow (*new_auth_tok)->session_key.encrypted_key_size; 273237fead6SMichael Halcrow } 274237fead6SMichael Halcrow ecryptfs_init_crypt_ctx(crypt_stat); 275237fead6SMichael Halcrow /* S2K identifier 3 (from RFC2440) */ 276237fead6SMichael Halcrow if (unlikely(data[(*packet_size)++] != 0x03)) { 277237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Only S2K ID 3 is currently " 278237fead6SMichael Halcrow "supported\n"); 279237fead6SMichael Halcrow rc = -ENOSYS; 280237fead6SMichael Halcrow goto out_free; 281237fead6SMichael Halcrow } 282237fead6SMichael Halcrow 283237fead6SMichael Halcrow /* TODO: finish the hash mapping */ 284237fead6SMichael Halcrow /* hash algorithm - one byte */ 285237fead6SMichael Halcrow switch (data[(*packet_size)++]) { 286237fead6SMichael Halcrow case 0x01: /* See RFC2440 for these numbers and their mappings */ 287237fead6SMichael Halcrow /* Choose MD5 */ 288237fead6SMichael Halcrow /* salt - ECRYPTFS_SALT_SIZE bytes */ 289237fead6SMichael Halcrow memcpy((*new_auth_tok)->token.password.salt, 290237fead6SMichael Halcrow &data[(*packet_size)], ECRYPTFS_SALT_SIZE); 291237fead6SMichael Halcrow (*packet_size) += ECRYPTFS_SALT_SIZE; 292237fead6SMichael Halcrow 293237fead6SMichael Halcrow /* This conversion was taken straight from RFC2440 */ 294237fead6SMichael Halcrow /* number of hash iterations - one byte */ 295237fead6SMichael Halcrow (*new_auth_tok)->token.password.hash_iterations = 296237fead6SMichael Halcrow ((u32) 16 + (data[(*packet_size)] & 15)) 297237fead6SMichael Halcrow << ((data[(*packet_size)] >> 4) + 6); 298237fead6SMichael Halcrow (*packet_size)++; 299237fead6SMichael Halcrow 300237fead6SMichael Halcrow /* encrypted session key - 301237fead6SMichael Halcrow * (body_size-5-ECRYPTFS_SALT_SIZE) bytes */ 302237fead6SMichael Halcrow memcpy((*new_auth_tok)->session_key.encrypted_key, 303237fead6SMichael Halcrow &data[(*packet_size)], 304237fead6SMichael Halcrow (*new_auth_tok)->session_key.encrypted_key_size); 305237fead6SMichael Halcrow (*packet_size) += 306237fead6SMichael Halcrow (*new_auth_tok)->session_key.encrypted_key_size; 307237fead6SMichael Halcrow (*new_auth_tok)->session_key.flags &= 308237fead6SMichael Halcrow ~ECRYPTFS_CONTAINS_DECRYPTED_KEY; 309237fead6SMichael Halcrow (*new_auth_tok)->session_key.flags |= 310237fead6SMichael Halcrow ECRYPTFS_CONTAINS_ENCRYPTED_KEY; 311237fead6SMichael Halcrow (*new_auth_tok)->token.password.hash_algo = 0x01; 312237fead6SMichael Halcrow break; 313237fead6SMichael Halcrow default: 314237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Unsupported hash algorithm: " 315237fead6SMichael Halcrow "[%d]\n", data[(*packet_size) - 1]); 316237fead6SMichael Halcrow rc = -ENOSYS; 317237fead6SMichael Halcrow goto out_free; 318237fead6SMichael Halcrow } 319237fead6SMichael Halcrow (*new_auth_tok)->token_type = ECRYPTFS_PASSWORD; 320237fead6SMichael Halcrow /* TODO: Parametarize; we might actually want userspace to 321237fead6SMichael Halcrow * decrypt the session key. */ 322237fead6SMichael Halcrow ECRYPTFS_CLEAR_FLAG((*new_auth_tok)->session_key.flags, 323237fead6SMichael Halcrow ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT); 324237fead6SMichael Halcrow ECRYPTFS_CLEAR_FLAG((*new_auth_tok)->session_key.flags, 325237fead6SMichael Halcrow ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT); 326237fead6SMichael Halcrow list_add(&auth_tok_list_item->list, auth_tok_list); 327237fead6SMichael Halcrow goto out; 328237fead6SMichael Halcrow out_free: 329237fead6SMichael Halcrow (*new_auth_tok) = NULL; 330237fead6SMichael Halcrow memset(auth_tok_list_item, 0, 331237fead6SMichael Halcrow sizeof(struct ecryptfs_auth_tok_list_item)); 332237fead6SMichael Halcrow kmem_cache_free(ecryptfs_auth_tok_list_item_cache, 333237fead6SMichael Halcrow auth_tok_list_item); 334237fead6SMichael Halcrow out: 335237fead6SMichael Halcrow if (rc) 336237fead6SMichael Halcrow (*packet_size) = 0; 337237fead6SMichael Halcrow return rc; 338237fead6SMichael Halcrow } 339237fead6SMichael Halcrow 340237fead6SMichael Halcrow /** 341237fead6SMichael Halcrow * parse_tag_11_packet 342237fead6SMichael Halcrow * @data: The raw bytes of the packet 343237fead6SMichael Halcrow * @contents: This function writes the data contents of the literal 344237fead6SMichael Halcrow * packet into this memory location 345237fead6SMichael Halcrow * @max_contents_bytes: The maximum number of bytes that this function 346237fead6SMichael Halcrow * is allowed to write into contents 347237fead6SMichael Halcrow * @tag_11_contents_size: This function writes the size of the parsed 348237fead6SMichael Halcrow * contents into this memory location; zero on 349237fead6SMichael Halcrow * error 350237fead6SMichael Halcrow * @packet_size: This function writes the size of the parsed packet 351237fead6SMichael Halcrow * into this memory location; zero on error 352237fead6SMichael Halcrow * @max_packet_size: maximum number of bytes to parse 353237fead6SMichael Halcrow * 354237fead6SMichael Halcrow * Returns zero on success; non-zero on error. 355237fead6SMichael Halcrow */ 356237fead6SMichael Halcrow static int 357237fead6SMichael Halcrow parse_tag_11_packet(unsigned char *data, unsigned char *contents, 358237fead6SMichael Halcrow size_t max_contents_bytes, size_t *tag_11_contents_size, 359237fead6SMichael Halcrow size_t *packet_size, size_t max_packet_size) 360237fead6SMichael Halcrow { 361237fead6SMichael Halcrow int rc = 0; 362237fead6SMichael Halcrow size_t body_size; 363237fead6SMichael Halcrow size_t length_size; 364237fead6SMichael Halcrow 365237fead6SMichael Halcrow (*packet_size) = 0; 366237fead6SMichael Halcrow (*tag_11_contents_size) = 0; 367237fead6SMichael Halcrow 368237fead6SMichael Halcrow /* check that: 369237fead6SMichael Halcrow * one byte for the Tag 11 ID flag 370237fead6SMichael Halcrow * two bytes for the Tag 11 length 371237fead6SMichael Halcrow * do not exceed the maximum_packet_size 372237fead6SMichael Halcrow */ 373237fead6SMichael Halcrow if (unlikely((*packet_size) + 3 > max_packet_size)) { 374237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Packet size exceeds max\n"); 375237fead6SMichael Halcrow rc = -EINVAL; 376237fead6SMichael Halcrow goto out; 377237fead6SMichael Halcrow } 378237fead6SMichael Halcrow 379237fead6SMichael Halcrow /* check for Tag 11 identifyer - one byte */ 380237fead6SMichael Halcrow if (data[(*packet_size)++] != ECRYPTFS_TAG_11_PACKET_TYPE) { 381237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, 382237fead6SMichael Halcrow "Invalid tag 11 packet format\n"); 383237fead6SMichael Halcrow rc = -EINVAL; 384237fead6SMichael Halcrow goto out; 385237fead6SMichael Halcrow } 386237fead6SMichael Halcrow 387237fead6SMichael Halcrow /* get Tag 11 content length - one or two bytes */ 388237fead6SMichael Halcrow rc = parse_packet_length(&data[(*packet_size)], &body_size, 389237fead6SMichael Halcrow &length_size); 390237fead6SMichael Halcrow if (rc) { 391237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, 392237fead6SMichael Halcrow "Invalid tag 11 packet format\n"); 393237fead6SMichael Halcrow goto out; 394237fead6SMichael Halcrow } 395237fead6SMichael Halcrow (*packet_size) += length_size; 396237fead6SMichael Halcrow 397237fead6SMichael Halcrow if (body_size < 13) { 398237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Invalid body size ([%d])\n", 399237fead6SMichael Halcrow body_size); 400237fead6SMichael Halcrow rc = -EINVAL; 401237fead6SMichael Halcrow goto out; 402237fead6SMichael Halcrow } 403237fead6SMichael Halcrow /* We have 13 bytes of surrounding packet values */ 404237fead6SMichael Halcrow (*tag_11_contents_size) = (body_size - 13); 405237fead6SMichael Halcrow 406237fead6SMichael Halcrow /* now we know the length of the remainting Tag 11 packet size: 407237fead6SMichael Halcrow * 14 fix bytes for: special flag one, special flag two, 408237fead6SMichael Halcrow * 12 skipped bytes 409237fead6SMichael Halcrow * body_size bytes minus the stuff above is the Tag 11 content 410237fead6SMichael Halcrow */ 411237fead6SMichael Halcrow /* FIXME why is the body size one byte smaller than the actual 412237fead6SMichael Halcrow * size of the body? 413237fead6SMichael Halcrow * this seems to be an error here as well as in 414237fead6SMichael Halcrow * write_tag_11_packet() */ 415237fead6SMichael Halcrow if (unlikely((*packet_size) + body_size + 1 > max_packet_size)) { 416237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Packet size exceeds max\n"); 417237fead6SMichael Halcrow rc = -EINVAL; 418237fead6SMichael Halcrow goto out; 419237fead6SMichael Halcrow } 420237fead6SMichael Halcrow 421237fead6SMichael Halcrow /* special flag one - one byte */ 422237fead6SMichael Halcrow if (data[(*packet_size)++] != 0x62) { 423237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Unrecognizable packet\n"); 424237fead6SMichael Halcrow rc = -EINVAL; 425237fead6SMichael Halcrow goto out; 426237fead6SMichael Halcrow } 427237fead6SMichael Halcrow 428237fead6SMichael Halcrow /* special flag two - one byte */ 429237fead6SMichael Halcrow if (data[(*packet_size)++] != 0x08) { 430237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Unrecognizable packet\n"); 431237fead6SMichael Halcrow rc = -EINVAL; 432237fead6SMichael Halcrow goto out; 433237fead6SMichael Halcrow } 434237fead6SMichael Halcrow 435237fead6SMichael Halcrow /* skip the next 12 bytes */ 436237fead6SMichael Halcrow (*packet_size) += 12; /* We don't care about the filename or 437237fead6SMichael Halcrow * the timestamp */ 438237fead6SMichael Halcrow 439237fead6SMichael Halcrow /* get the Tag 11 contents - tag_11_contents_size bytes */ 440237fead6SMichael Halcrow memcpy(contents, &data[(*packet_size)], (*tag_11_contents_size)); 441237fead6SMichael Halcrow (*packet_size) += (*tag_11_contents_size); 442237fead6SMichael Halcrow 443237fead6SMichael Halcrow out: 444237fead6SMichael Halcrow if (rc) { 445237fead6SMichael Halcrow (*packet_size) = 0; 446237fead6SMichael Halcrow (*tag_11_contents_size) = 0; 447237fead6SMichael Halcrow } 448237fead6SMichael Halcrow return rc; 449237fead6SMichael Halcrow } 450237fead6SMichael Halcrow 451237fead6SMichael Halcrow /** 452237fead6SMichael Halcrow * decrypt_session_key - Decrypt the session key with the given auth_tok. 453237fead6SMichael Halcrow * 454237fead6SMichael Halcrow * Returns Zero on success; non-zero error otherwise. 455237fead6SMichael Halcrow */ 456237fead6SMichael Halcrow static int decrypt_session_key(struct ecryptfs_auth_tok *auth_tok, 457237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat) 458237fead6SMichael Halcrow { 459237fead6SMichael Halcrow struct ecryptfs_password *password_s_ptr; 460237fead6SMichael Halcrow struct scatterlist src_sg[2], dst_sg[2]; 461237fead6SMichael Halcrow struct mutex *tfm_mutex = NULL; 462237fead6SMichael Halcrow /* TODO: Use virt_to_scatterlist for these */ 463237fead6SMichael Halcrow char *encrypted_session_key; 464237fead6SMichael Halcrow char *session_key; 4658bba066fSMichael Halcrow struct blkcipher_desc desc = { 4668bba066fSMichael Halcrow .flags = CRYPTO_TFM_REQ_MAY_SLEEP 4678bba066fSMichael Halcrow }; 4688bba066fSMichael Halcrow int rc = 0; 469237fead6SMichael Halcrow 470237fead6SMichael Halcrow password_s_ptr = &auth_tok->token.password; 471237fead6SMichael Halcrow if (ECRYPTFS_CHECK_FLAG(password_s_ptr->flags, 472237fead6SMichael Halcrow ECRYPTFS_SESSION_KEY_ENCRYPTION_KEY_SET)) 473237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Session key encryption key " 474237fead6SMichael Halcrow "set; skipping key generation\n"); 475237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Session key encryption key (size [%d])" 476237fead6SMichael Halcrow ":\n", 477237fead6SMichael Halcrow password_s_ptr->session_key_encryption_key_bytes); 478237fead6SMichael Halcrow if (ecryptfs_verbosity > 0) 479237fead6SMichael Halcrow ecryptfs_dump_hex(password_s_ptr->session_key_encryption_key, 480237fead6SMichael Halcrow password_s_ptr-> 481237fead6SMichael Halcrow session_key_encryption_key_bytes); 482237fead6SMichael Halcrow if (!strcmp(crypt_stat->cipher, 483237fead6SMichael Halcrow crypt_stat->mount_crypt_stat->global_default_cipher_name) 484237fead6SMichael Halcrow && crypt_stat->mount_crypt_stat->global_key_tfm) { 4858bba066fSMichael Halcrow desc.tfm = crypt_stat->mount_crypt_stat->global_key_tfm; 486237fead6SMichael Halcrow tfm_mutex = &crypt_stat->mount_crypt_stat->global_key_tfm_mutex; 487237fead6SMichael Halcrow } else { 4888bba066fSMichael Halcrow char *full_alg_name; 4898bba066fSMichael Halcrow 4908bba066fSMichael Halcrow rc = ecryptfs_crypto_api_algify_cipher_name(&full_alg_name, 4918bba066fSMichael Halcrow crypt_stat->cipher, 4928bba066fSMichael Halcrow "ecb"); 4938bba066fSMichael Halcrow if (rc) 4948bba066fSMichael Halcrow goto out; 4958bba066fSMichael Halcrow desc.tfm = crypto_alloc_blkcipher(full_alg_name, 0, 4968bba066fSMichael Halcrow CRYPTO_ALG_ASYNC); 4978bba066fSMichael Halcrow kfree(full_alg_name); 4988bba066fSMichael Halcrow if (IS_ERR(desc.tfm)) { 4998bba066fSMichael Halcrow rc = PTR_ERR(desc.tfm); 5008bba066fSMichael Halcrow printk(KERN_ERR "Error allocating crypto context; " 5018bba066fSMichael Halcrow "rc = [%d]\n", rc); 502237fead6SMichael Halcrow goto out; 503237fead6SMichael Halcrow } 5048bba066fSMichael Halcrow crypto_blkcipher_set_flags(desc.tfm, CRYPTO_TFM_REQ_WEAK_KEY); 505237fead6SMichael Halcrow } 506237fead6SMichael Halcrow if (tfm_mutex) 507237fead6SMichael Halcrow mutex_lock(tfm_mutex); 5088bba066fSMichael Halcrow rc = crypto_blkcipher_setkey(desc.tfm, 509e5d9cbdeSMichael Halcrow password_s_ptr->session_key_encryption_key, 510237fead6SMichael Halcrow crypt_stat->key_size); 511e5d9cbdeSMichael Halcrow if (rc < 0) { 512e5d9cbdeSMichael Halcrow printk(KERN_ERR "Error setting key for crypto context\n"); 513e5d9cbdeSMichael Halcrow rc = -EINVAL; 514e5d9cbdeSMichael Halcrow goto out_free_tfm; 515e5d9cbdeSMichael Halcrow } 516237fead6SMichael Halcrow /* TODO: virt_to_scatterlist */ 517237fead6SMichael Halcrow encrypted_session_key = (char *)__get_free_page(GFP_KERNEL); 518237fead6SMichael Halcrow if (!encrypted_session_key) { 519237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Out of memory\n"); 520237fead6SMichael Halcrow rc = -ENOMEM; 521237fead6SMichael Halcrow goto out_free_tfm; 522237fead6SMichael Halcrow } 523237fead6SMichael Halcrow session_key = (char *)__get_free_page(GFP_KERNEL); 524237fead6SMichael Halcrow if (!session_key) { 525237fead6SMichael Halcrow kfree(encrypted_session_key); 526237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Out of memory\n"); 527237fead6SMichael Halcrow rc = -ENOMEM; 528237fead6SMichael Halcrow goto out_free_tfm; 529237fead6SMichael Halcrow } 530237fead6SMichael Halcrow memcpy(encrypted_session_key, auth_tok->session_key.encrypted_key, 531237fead6SMichael Halcrow auth_tok->session_key.encrypted_key_size); 532237fead6SMichael Halcrow src_sg[0].page = virt_to_page(encrypted_session_key); 533237fead6SMichael Halcrow src_sg[0].offset = 0; 534237fead6SMichael Halcrow BUG_ON(auth_tok->session_key.encrypted_key_size > PAGE_CACHE_SIZE); 535237fead6SMichael Halcrow src_sg[0].length = auth_tok->session_key.encrypted_key_size; 536237fead6SMichael Halcrow dst_sg[0].page = virt_to_page(session_key); 537237fead6SMichael Halcrow dst_sg[0].offset = 0; 538237fead6SMichael Halcrow auth_tok->session_key.decrypted_key_size = 539237fead6SMichael Halcrow auth_tok->session_key.encrypted_key_size; 540237fead6SMichael Halcrow dst_sg[0].length = auth_tok->session_key.encrypted_key_size; 5418bba066fSMichael Halcrow rc = crypto_blkcipher_decrypt(&desc, dst_sg, src_sg, 542237fead6SMichael Halcrow auth_tok->session_key.encrypted_key_size); 5438bba066fSMichael Halcrow if (rc) { 5448bba066fSMichael Halcrow printk(KERN_ERR "Error decrypting; rc = [%d]\n", rc); 5458bba066fSMichael Halcrow goto out_free_memory; 5468bba066fSMichael Halcrow } 547237fead6SMichael Halcrow auth_tok->session_key.decrypted_key_size = 548237fead6SMichael Halcrow auth_tok->session_key.encrypted_key_size; 549237fead6SMichael Halcrow memcpy(auth_tok->session_key.decrypted_key, session_key, 550237fead6SMichael Halcrow auth_tok->session_key.decrypted_key_size); 551237fead6SMichael Halcrow auth_tok->session_key.flags |= ECRYPTFS_CONTAINS_DECRYPTED_KEY; 552237fead6SMichael Halcrow memcpy(crypt_stat->key, auth_tok->session_key.decrypted_key, 553237fead6SMichael Halcrow auth_tok->session_key.decrypted_key_size); 554237fead6SMichael Halcrow ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_KEY_VALID); 555237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Decrypted session key:\n"); 556237fead6SMichael Halcrow if (ecryptfs_verbosity > 0) 557237fead6SMichael Halcrow ecryptfs_dump_hex(crypt_stat->key, 558237fead6SMichael Halcrow crypt_stat->key_size); 5598bba066fSMichael Halcrow out_free_memory: 560237fead6SMichael Halcrow memset(encrypted_session_key, 0, PAGE_CACHE_SIZE); 561237fead6SMichael Halcrow free_page((unsigned long)encrypted_session_key); 562237fead6SMichael Halcrow memset(session_key, 0, PAGE_CACHE_SIZE); 563237fead6SMichael Halcrow free_page((unsigned long)session_key); 564237fead6SMichael Halcrow out_free_tfm: 565237fead6SMichael Halcrow if (tfm_mutex) 566237fead6SMichael Halcrow mutex_unlock(tfm_mutex); 567237fead6SMichael Halcrow else 5688bba066fSMichael Halcrow crypto_free_blkcipher(desc.tfm); 569237fead6SMichael Halcrow out: 570237fead6SMichael Halcrow return rc; 571237fead6SMichael Halcrow } 572237fead6SMichael Halcrow 573237fead6SMichael Halcrow /** 574237fead6SMichael Halcrow * ecryptfs_parse_packet_set 575237fead6SMichael Halcrow * @dest: The header page in memory 576237fead6SMichael Halcrow * @version: Version of file format, to guide parsing behavior 577237fead6SMichael Halcrow * 578237fead6SMichael Halcrow * Get crypt_stat to have the file's session key if the requisite key 579237fead6SMichael Halcrow * is available to decrypt the session key. 580237fead6SMichael Halcrow * 581237fead6SMichael Halcrow * Returns Zero if a valid authentication token was retrieved and 582237fead6SMichael Halcrow * processed; negative value for file not encrypted or for error 583237fead6SMichael Halcrow * conditions. 584237fead6SMichael Halcrow */ 585237fead6SMichael Halcrow int ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat, 586237fead6SMichael Halcrow unsigned char *src, 587237fead6SMichael Halcrow struct dentry *ecryptfs_dentry) 588237fead6SMichael Halcrow { 589237fead6SMichael Halcrow size_t i = 0; 590237fead6SMichael Halcrow int rc = 0; 591237fead6SMichael Halcrow size_t found_auth_tok = 0; 592237fead6SMichael Halcrow size_t next_packet_is_auth_tok_packet; 593237fead6SMichael Halcrow char sig[ECRYPTFS_SIG_SIZE_HEX]; 594237fead6SMichael Halcrow struct list_head auth_tok_list; 595237fead6SMichael Halcrow struct list_head *walker; 596237fead6SMichael Halcrow struct ecryptfs_auth_tok *chosen_auth_tok = NULL; 597237fead6SMichael Halcrow struct ecryptfs_mount_crypt_stat *mount_crypt_stat = 598237fead6SMichael Halcrow &ecryptfs_superblock_to_private( 599237fead6SMichael Halcrow ecryptfs_dentry->d_sb)->mount_crypt_stat; 600237fead6SMichael Halcrow struct ecryptfs_auth_tok *candidate_auth_tok = NULL; 601237fead6SMichael Halcrow size_t packet_size; 602237fead6SMichael Halcrow struct ecryptfs_auth_tok *new_auth_tok; 603237fead6SMichael Halcrow unsigned char sig_tmp_space[ECRYPTFS_SIG_SIZE]; 604237fead6SMichael Halcrow size_t tag_11_contents_size; 605237fead6SMichael Halcrow size_t tag_11_packet_size; 606237fead6SMichael Halcrow 607237fead6SMichael Halcrow INIT_LIST_HEAD(&auth_tok_list); 608237fead6SMichael Halcrow /* Parse the header to find as many packets as we can, these will be 609237fead6SMichael Halcrow * added the our &auth_tok_list */ 610237fead6SMichael Halcrow next_packet_is_auth_tok_packet = 1; 611237fead6SMichael Halcrow while (next_packet_is_auth_tok_packet) { 612237fead6SMichael Halcrow size_t max_packet_size = ((PAGE_CACHE_SIZE - 8) - i); 613237fead6SMichael Halcrow 614237fead6SMichael Halcrow switch (src[i]) { 615237fead6SMichael Halcrow case ECRYPTFS_TAG_3_PACKET_TYPE: 616237fead6SMichael Halcrow rc = parse_tag_3_packet(crypt_stat, 617237fead6SMichael Halcrow (unsigned char *)&src[i], 618237fead6SMichael Halcrow &auth_tok_list, &new_auth_tok, 619237fead6SMichael Halcrow &packet_size, max_packet_size); 620237fead6SMichael Halcrow if (rc) { 621237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error parsing " 622237fead6SMichael Halcrow "tag 3 packet\n"); 623237fead6SMichael Halcrow rc = -EIO; 624237fead6SMichael Halcrow goto out_wipe_list; 625237fead6SMichael Halcrow } 626237fead6SMichael Halcrow i += packet_size; 627237fead6SMichael Halcrow rc = parse_tag_11_packet((unsigned char *)&src[i], 628237fead6SMichael Halcrow sig_tmp_space, 629237fead6SMichael Halcrow ECRYPTFS_SIG_SIZE, 630237fead6SMichael Halcrow &tag_11_contents_size, 631237fead6SMichael Halcrow &tag_11_packet_size, 632237fead6SMichael Halcrow max_packet_size); 633237fead6SMichael Halcrow if (rc) { 634237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "No valid " 635237fead6SMichael Halcrow "(ecryptfs-specific) literal " 636237fead6SMichael Halcrow "packet containing " 637237fead6SMichael Halcrow "authentication token " 638237fead6SMichael Halcrow "signature found after " 639237fead6SMichael Halcrow "tag 3 packet\n"); 640237fead6SMichael Halcrow rc = -EIO; 641237fead6SMichael Halcrow goto out_wipe_list; 642237fead6SMichael Halcrow } 643237fead6SMichael Halcrow i += tag_11_packet_size; 644237fead6SMichael Halcrow if (ECRYPTFS_SIG_SIZE != tag_11_contents_size) { 645237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Expected " 646237fead6SMichael Halcrow "signature of size [%d]; " 647237fead6SMichael Halcrow "read size [%d]\n", 648237fead6SMichael Halcrow ECRYPTFS_SIG_SIZE, 649237fead6SMichael Halcrow tag_11_contents_size); 650237fead6SMichael Halcrow rc = -EIO; 651237fead6SMichael Halcrow goto out_wipe_list; 652237fead6SMichael Halcrow } 653237fead6SMichael Halcrow ecryptfs_to_hex(new_auth_tok->token.password.signature, 654237fead6SMichael Halcrow sig_tmp_space, tag_11_contents_size); 655237fead6SMichael Halcrow new_auth_tok->token.password.signature[ 656237fead6SMichael Halcrow ECRYPTFS_PASSWORD_SIG_SIZE] = '\0'; 657237fead6SMichael Halcrow ECRYPTFS_SET_FLAG(crypt_stat->flags, 658237fead6SMichael Halcrow ECRYPTFS_ENCRYPTED); 659237fead6SMichael Halcrow break; 660237fead6SMichael Halcrow case ECRYPTFS_TAG_11_PACKET_TYPE: 661237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Invalid packet set " 662237fead6SMichael Halcrow "(Tag 11 not allowed by itself)\n"); 663237fead6SMichael Halcrow rc = -EIO; 664237fead6SMichael Halcrow goto out_wipe_list; 665237fead6SMichael Halcrow break; 666237fead6SMichael Halcrow default: 667237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "No packet at offset " 668237fead6SMichael Halcrow "[%d] of the file header; hex value of " 669237fead6SMichael Halcrow "character is [0x%.2x]\n", i, src[i]); 670237fead6SMichael Halcrow next_packet_is_auth_tok_packet = 0; 671237fead6SMichael Halcrow } 672237fead6SMichael Halcrow } 673237fead6SMichael Halcrow if (list_empty(&auth_tok_list)) { 674237fead6SMichael Halcrow rc = -EINVAL; /* Do not support non-encrypted files in 675237fead6SMichael Halcrow * the 0.1 release */ 676237fead6SMichael Halcrow goto out; 677237fead6SMichael Halcrow } 678237fead6SMichael Halcrow /* If we have a global auth tok, then we should try to use 679237fead6SMichael Halcrow * it */ 680237fead6SMichael Halcrow if (mount_crypt_stat->global_auth_tok) { 681237fead6SMichael Halcrow memcpy(sig, mount_crypt_stat->global_auth_tok_sig, 682237fead6SMichael Halcrow ECRYPTFS_SIG_SIZE_HEX); 683237fead6SMichael Halcrow chosen_auth_tok = mount_crypt_stat->global_auth_tok; 684237fead6SMichael Halcrow } else 685237fead6SMichael Halcrow BUG(); /* We should always have a global auth tok in 686237fead6SMichael Halcrow * the 0.1 release */ 687237fead6SMichael Halcrow /* Scan list to see if our chosen_auth_tok works */ 688237fead6SMichael Halcrow list_for_each(walker, &auth_tok_list) { 689237fead6SMichael Halcrow struct ecryptfs_auth_tok_list_item *auth_tok_list_item; 690237fead6SMichael Halcrow auth_tok_list_item = 691237fead6SMichael Halcrow list_entry(walker, struct ecryptfs_auth_tok_list_item, 692237fead6SMichael Halcrow list); 693237fead6SMichael Halcrow candidate_auth_tok = &auth_tok_list_item->auth_tok; 694237fead6SMichael Halcrow if (unlikely(ecryptfs_verbosity > 0)) { 695237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, 696237fead6SMichael Halcrow "Considering cadidate auth tok:\n"); 697237fead6SMichael Halcrow ecryptfs_dump_auth_tok(candidate_auth_tok); 698237fead6SMichael Halcrow } 699237fead6SMichael Halcrow /* TODO: Replace ECRYPTFS_SIG_SIZE_HEX w/ dynamic value */ 700237fead6SMichael Halcrow if (candidate_auth_tok->token_type == ECRYPTFS_PASSWORD 701237fead6SMichael Halcrow && !strncmp(candidate_auth_tok->token.password.signature, 702237fead6SMichael Halcrow sig, ECRYPTFS_SIG_SIZE_HEX)) { 703237fead6SMichael Halcrow found_auth_tok = 1; 704237fead6SMichael Halcrow goto leave_list; 705237fead6SMichael Halcrow /* TODO: Transfer the common salt into the 706237fead6SMichael Halcrow * crypt_stat salt */ 707237fead6SMichael Halcrow } 708237fead6SMichael Halcrow } 709237fead6SMichael Halcrow leave_list: 710237fead6SMichael Halcrow if (!found_auth_tok) { 711237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Could not find authentication " 712237fead6SMichael Halcrow "token on temporary list for sig [%.*s]\n", 713237fead6SMichael Halcrow ECRYPTFS_SIG_SIZE_HEX, sig); 714237fead6SMichael Halcrow rc = -EIO; 715237fead6SMichael Halcrow goto out_wipe_list; 716237fead6SMichael Halcrow } else { 717237fead6SMichael Halcrow memcpy(&(candidate_auth_tok->token.password), 718237fead6SMichael Halcrow &(chosen_auth_tok->token.password), 719237fead6SMichael Halcrow sizeof(struct ecryptfs_password)); 720237fead6SMichael Halcrow rc = decrypt_session_key(candidate_auth_tok, crypt_stat); 721237fead6SMichael Halcrow if (rc) { 722237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error decrypting the " 723237fead6SMichael Halcrow "session key\n"); 724237fead6SMichael Halcrow goto out_wipe_list; 725237fead6SMichael Halcrow } 726237fead6SMichael Halcrow rc = ecryptfs_compute_root_iv(crypt_stat); 727237fead6SMichael Halcrow if (rc) { 728237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error computing " 729237fead6SMichael Halcrow "the root IV\n"); 730237fead6SMichael Halcrow goto out_wipe_list; 731237fead6SMichael Halcrow } 732237fead6SMichael Halcrow } 733237fead6SMichael Halcrow rc = ecryptfs_init_crypt_ctx(crypt_stat); 734237fead6SMichael Halcrow if (rc) { 735237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error initializing crypto " 736237fead6SMichael Halcrow "context for cipher [%s]; rc = [%d]\n", 737237fead6SMichael Halcrow crypt_stat->cipher, rc); 738237fead6SMichael Halcrow } 739237fead6SMichael Halcrow out_wipe_list: 740237fead6SMichael Halcrow wipe_auth_tok_list(&auth_tok_list); 741237fead6SMichael Halcrow out: 742237fead6SMichael Halcrow return rc; 743237fead6SMichael Halcrow } 744237fead6SMichael Halcrow 745237fead6SMichael Halcrow /** 746237fead6SMichael Halcrow * write_tag_11_packet 747237fead6SMichael Halcrow * @dest: Target into which Tag 11 packet is to be written 748237fead6SMichael Halcrow * @max: Maximum packet length 749237fead6SMichael Halcrow * @contents: Byte array of contents to copy in 750237fead6SMichael Halcrow * @contents_length: Number of bytes in contents 751237fead6SMichael Halcrow * @packet_length: Length of the Tag 11 packet written; zero on error 752237fead6SMichael Halcrow * 753237fead6SMichael Halcrow * Returns zero on success; non-zero on error. 754237fead6SMichael Halcrow */ 755237fead6SMichael Halcrow static int 756237fead6SMichael Halcrow write_tag_11_packet(char *dest, int max, char *contents, size_t contents_length, 757237fead6SMichael Halcrow size_t *packet_length) 758237fead6SMichael Halcrow { 759237fead6SMichael Halcrow int rc = 0; 760237fead6SMichael Halcrow size_t packet_size_length; 761237fead6SMichael Halcrow 762237fead6SMichael Halcrow (*packet_length) = 0; 763237fead6SMichael Halcrow if ((13 + contents_length) > max) { 764237fead6SMichael Halcrow rc = -EINVAL; 765237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Packet length larger than " 766237fead6SMichael Halcrow "maximum allowable\n"); 767237fead6SMichael Halcrow goto out; 768237fead6SMichael Halcrow } 769237fead6SMichael Halcrow /* General packet header */ 770237fead6SMichael Halcrow /* Packet tag */ 771237fead6SMichael Halcrow dest[(*packet_length)++] = ECRYPTFS_TAG_11_PACKET_TYPE; 772237fead6SMichael Halcrow /* Packet length */ 773237fead6SMichael Halcrow rc = write_packet_length(&dest[(*packet_length)], 774237fead6SMichael Halcrow (13 + contents_length), &packet_size_length); 775237fead6SMichael Halcrow if (rc) { 776237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error generating tag 11 packet " 777237fead6SMichael Halcrow "header; cannot generate packet length\n"); 778237fead6SMichael Halcrow goto out; 779237fead6SMichael Halcrow } 780237fead6SMichael Halcrow (*packet_length) += packet_size_length; 781237fead6SMichael Halcrow /* Tag 11 specific */ 782237fead6SMichael Halcrow /* One-octet field that describes how the data is formatted */ 783237fead6SMichael Halcrow dest[(*packet_length)++] = 0x62; /* binary data */ 784237fead6SMichael Halcrow /* One-octet filename length followed by filename */ 785237fead6SMichael Halcrow dest[(*packet_length)++] = 8; 786237fead6SMichael Halcrow memcpy(&dest[(*packet_length)], "_CONSOLE", 8); 787237fead6SMichael Halcrow (*packet_length) += 8; 788237fead6SMichael Halcrow /* Four-octet number indicating modification date */ 789237fead6SMichael Halcrow memset(&dest[(*packet_length)], 0x00, 4); 790237fead6SMichael Halcrow (*packet_length) += 4; 791237fead6SMichael Halcrow /* Remainder is literal data */ 792237fead6SMichael Halcrow memcpy(&dest[(*packet_length)], contents, contents_length); 793237fead6SMichael Halcrow (*packet_length) += contents_length; 794237fead6SMichael Halcrow out: 795237fead6SMichael Halcrow if (rc) 796237fead6SMichael Halcrow (*packet_length) = 0; 797237fead6SMichael Halcrow return rc; 798237fead6SMichael Halcrow } 799237fead6SMichael Halcrow 800237fead6SMichael Halcrow /** 801237fead6SMichael Halcrow * write_tag_3_packet 802237fead6SMichael Halcrow * @dest: Buffer into which to write the packet 803237fead6SMichael Halcrow * @max: Maximum number of bytes that can be written 804237fead6SMichael Halcrow * @auth_tok: Authentication token 805237fead6SMichael Halcrow * @crypt_stat: The cryptographic context 806237fead6SMichael Halcrow * @key_rec: encrypted key 807237fead6SMichael Halcrow * @packet_size: This function will write the number of bytes that end 808237fead6SMichael Halcrow * up constituting the packet; set to zero on error 809237fead6SMichael Halcrow * 810237fead6SMichael Halcrow * Returns zero on success; non-zero on error. 811237fead6SMichael Halcrow */ 812237fead6SMichael Halcrow static int 813237fead6SMichael Halcrow write_tag_3_packet(char *dest, size_t max, struct ecryptfs_auth_tok *auth_tok, 814237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat, 815237fead6SMichael Halcrow struct ecryptfs_key_record *key_rec, size_t *packet_size) 816237fead6SMichael Halcrow { 817237fead6SMichael Halcrow size_t i; 818237fead6SMichael Halcrow size_t signature_is_valid = 0; 819237fead6SMichael Halcrow size_t encrypted_session_key_valid = 0; 820237fead6SMichael Halcrow char session_key_encryption_key[ECRYPTFS_MAX_KEY_BYTES]; 821237fead6SMichael Halcrow struct scatterlist dest_sg[2]; 822237fead6SMichael Halcrow struct scatterlist src_sg[2]; 823237fead6SMichael Halcrow struct mutex *tfm_mutex = NULL; 824237fead6SMichael Halcrow size_t key_rec_size; 825237fead6SMichael Halcrow size_t packet_size_length; 826237fead6SMichael Halcrow size_t cipher_code; 8278bba066fSMichael Halcrow struct blkcipher_desc desc = { 8288bba066fSMichael Halcrow .tfm = NULL, 8298bba066fSMichael Halcrow .flags = CRYPTO_TFM_REQ_MAY_SLEEP 8308bba066fSMichael Halcrow }; 8318bba066fSMichael Halcrow int rc = 0; 832237fead6SMichael Halcrow 833237fead6SMichael Halcrow (*packet_size) = 0; 834237fead6SMichael Halcrow /* Check for a valid signature on the auth_tok */ 835237fead6SMichael Halcrow for (i = 0; i < ECRYPTFS_SIG_SIZE_HEX; i++) 836237fead6SMichael Halcrow signature_is_valid |= auth_tok->token.password.signature[i]; 837237fead6SMichael Halcrow if (!signature_is_valid) 838237fead6SMichael Halcrow BUG(); 839237fead6SMichael Halcrow ecryptfs_from_hex((*key_rec).sig, auth_tok->token.password.signature, 840237fead6SMichael Halcrow ECRYPTFS_SIG_SIZE); 841237fead6SMichael Halcrow encrypted_session_key_valid = 0; 842237fead6SMichael Halcrow for (i = 0; i < crypt_stat->key_size; i++) 843237fead6SMichael Halcrow encrypted_session_key_valid |= 844237fead6SMichael Halcrow auth_tok->session_key.encrypted_key[i]; 845237fead6SMichael Halcrow if (encrypted_session_key_valid) { 846237fead6SMichael Halcrow memcpy((*key_rec).enc_key, 847237fead6SMichael Halcrow auth_tok->session_key.encrypted_key, 848237fead6SMichael Halcrow auth_tok->session_key.encrypted_key_size); 849237fead6SMichael Halcrow goto encrypted_session_key_set; 850237fead6SMichael Halcrow } 851237fead6SMichael Halcrow if (auth_tok->session_key.encrypted_key_size == 0) 852237fead6SMichael Halcrow auth_tok->session_key.encrypted_key_size = 853237fead6SMichael Halcrow crypt_stat->key_size; 854237fead6SMichael Halcrow if (crypt_stat->key_size == 24 855237fead6SMichael Halcrow && strcmp("aes", crypt_stat->cipher) == 0) { 856237fead6SMichael Halcrow memset((crypt_stat->key + 24), 0, 8); 857237fead6SMichael Halcrow auth_tok->session_key.encrypted_key_size = 32; 858237fead6SMichael Halcrow } 859237fead6SMichael Halcrow (*key_rec).enc_key_size = 860237fead6SMichael Halcrow auth_tok->session_key.encrypted_key_size; 861237fead6SMichael Halcrow if (ECRYPTFS_CHECK_FLAG(auth_tok->token.password.flags, 862237fead6SMichael Halcrow ECRYPTFS_SESSION_KEY_ENCRYPTION_KEY_SET)) { 863237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Using previously generated " 864237fead6SMichael Halcrow "session key encryption key of size [%d]\n", 865237fead6SMichael Halcrow auth_tok->token.password. 866237fead6SMichael Halcrow session_key_encryption_key_bytes); 867237fead6SMichael Halcrow memcpy(session_key_encryption_key, 868237fead6SMichael Halcrow auth_tok->token.password.session_key_encryption_key, 869237fead6SMichael Halcrow crypt_stat->key_size); 870237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, 871237fead6SMichael Halcrow "Cached session key " "encryption key: \n"); 872237fead6SMichael Halcrow if (ecryptfs_verbosity > 0) 873237fead6SMichael Halcrow ecryptfs_dump_hex(session_key_encryption_key, 16); 874237fead6SMichael Halcrow } 875237fead6SMichael Halcrow if (unlikely(ecryptfs_verbosity > 0)) { 876237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Session key encryption key:\n"); 877237fead6SMichael Halcrow ecryptfs_dump_hex(session_key_encryption_key, 16); 878237fead6SMichael Halcrow } 879237fead6SMichael Halcrow rc = virt_to_scatterlist(crypt_stat->key, 880237fead6SMichael Halcrow (*key_rec).enc_key_size, src_sg, 2); 881237fead6SMichael Halcrow if (!rc) { 882237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error generating scatterlist " 883237fead6SMichael Halcrow "for crypt_stat session key\n"); 884237fead6SMichael Halcrow rc = -ENOMEM; 885237fead6SMichael Halcrow goto out; 886237fead6SMichael Halcrow } 887237fead6SMichael Halcrow rc = virt_to_scatterlist((*key_rec).enc_key, 888237fead6SMichael Halcrow (*key_rec).enc_key_size, dest_sg, 2); 889237fead6SMichael Halcrow if (!rc) { 890237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error generating scatterlist " 891237fead6SMichael Halcrow "for crypt_stat encrypted session key\n"); 892237fead6SMichael Halcrow rc = -ENOMEM; 893237fead6SMichael Halcrow goto out; 894237fead6SMichael Halcrow } 895237fead6SMichael Halcrow if (!strcmp(crypt_stat->cipher, 896237fead6SMichael Halcrow crypt_stat->mount_crypt_stat->global_default_cipher_name) 897237fead6SMichael Halcrow && crypt_stat->mount_crypt_stat->global_key_tfm) { 8988bba066fSMichael Halcrow desc.tfm = crypt_stat->mount_crypt_stat->global_key_tfm; 899237fead6SMichael Halcrow tfm_mutex = &crypt_stat->mount_crypt_stat->global_key_tfm_mutex; 9008bba066fSMichael Halcrow } else { 9018bba066fSMichael Halcrow char *full_alg_name; 9028bba066fSMichael Halcrow 9038bba066fSMichael Halcrow rc = ecryptfs_crypto_api_algify_cipher_name(&full_alg_name, 9048bba066fSMichael Halcrow crypt_stat->cipher, 9058bba066fSMichael Halcrow "ecb"); 9068bba066fSMichael Halcrow if (rc) 907237fead6SMichael Halcrow goto out; 9088bba066fSMichael Halcrow desc.tfm = crypto_alloc_blkcipher(full_alg_name, 0, 9098bba066fSMichael Halcrow CRYPTO_ALG_ASYNC); 9108bba066fSMichael Halcrow kfree(full_alg_name); 9118bba066fSMichael Halcrow if (IS_ERR(desc.tfm)) { 9128bba066fSMichael Halcrow rc = PTR_ERR(desc.tfm); 9138bba066fSMichael Halcrow ecryptfs_printk(KERN_ERR, "Could not initialize crypto " 9148bba066fSMichael Halcrow "context for cipher [%s]; rc = [%d]\n", 9158bba066fSMichael Halcrow crypt_stat->cipher, rc); 9168bba066fSMichael Halcrow goto out; 9178bba066fSMichael Halcrow } 9188bba066fSMichael Halcrow crypto_blkcipher_set_flags(desc.tfm, CRYPTO_TFM_REQ_WEAK_KEY); 919237fead6SMichael Halcrow } 920237fead6SMichael Halcrow if (tfm_mutex) 921237fead6SMichael Halcrow mutex_lock(tfm_mutex); 9228bba066fSMichael Halcrow rc = crypto_blkcipher_setkey(desc.tfm, session_key_encryption_key, 923237fead6SMichael Halcrow crypt_stat->key_size); 924237fead6SMichael Halcrow if (rc < 0) { 925237fead6SMichael Halcrow if (tfm_mutex) 926237fead6SMichael Halcrow mutex_unlock(tfm_mutex); 927237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error setting key for crypto " 9288bba066fSMichael Halcrow "context; rc = [%d]\n", rc); 929237fead6SMichael Halcrow goto out; 930237fead6SMichael Halcrow } 931237fead6SMichael Halcrow rc = 0; 932237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Encrypting [%d] bytes of the key\n", 933237fead6SMichael Halcrow crypt_stat->key_size); 9348bba066fSMichael Halcrow rc = crypto_blkcipher_encrypt(&desc, dest_sg, src_sg, 935237fead6SMichael Halcrow (*key_rec).enc_key_size); 9368bba066fSMichael Halcrow if (rc) { 9378bba066fSMichael Halcrow printk(KERN_ERR "Error encrypting; rc = [%d]\n", rc); 9388bba066fSMichael Halcrow goto out; 9398bba066fSMichael Halcrow } 940237fead6SMichael Halcrow if (tfm_mutex) 941237fead6SMichael Halcrow mutex_unlock(tfm_mutex); 942237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "This should be the encrypted key:\n"); 943237fead6SMichael Halcrow if (ecryptfs_verbosity > 0) 944237fead6SMichael Halcrow ecryptfs_dump_hex((*key_rec).enc_key, 945237fead6SMichael Halcrow (*key_rec).enc_key_size); 946237fead6SMichael Halcrow encrypted_session_key_set: 947237fead6SMichael Halcrow /* Now we have a valid key_rec. Append it to the 948237fead6SMichael Halcrow * key_rec set. */ 949237fead6SMichael Halcrow key_rec_size = (sizeof(struct ecryptfs_key_record) 950237fead6SMichael Halcrow - ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES 951237fead6SMichael Halcrow + ((*key_rec).enc_key_size)); 952237fead6SMichael Halcrow /* TODO: Include a packet size limit as a parameter to this 953237fead6SMichael Halcrow * function once we have multi-packet headers (for versions 954237fead6SMichael Halcrow * later than 0.1 */ 955237fead6SMichael Halcrow if (key_rec_size >= ECRYPTFS_MAX_KEYSET_SIZE) { 956237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Keyset too large\n"); 957237fead6SMichael Halcrow rc = -EINVAL; 958237fead6SMichael Halcrow goto out; 959237fead6SMichael Halcrow } 960237fead6SMichael Halcrow /* TODO: Packet size limit */ 961237fead6SMichael Halcrow /* We have 5 bytes of surrounding packet data */ 962237fead6SMichael Halcrow if ((0x05 + ECRYPTFS_SALT_SIZE 963237fead6SMichael Halcrow + (*key_rec).enc_key_size) >= max) { 964237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Authentication token is too " 965237fead6SMichael Halcrow "large\n"); 966237fead6SMichael Halcrow rc = -EINVAL; 967237fead6SMichael Halcrow goto out; 968237fead6SMichael Halcrow } 969237fead6SMichael Halcrow /* This format is inspired by OpenPGP; see RFC 2440 970237fead6SMichael Halcrow * packet tag 3 */ 971237fead6SMichael Halcrow dest[(*packet_size)++] = ECRYPTFS_TAG_3_PACKET_TYPE; 972237fead6SMichael Halcrow /* ver+cipher+s2k+hash+salt+iter+enc_key */ 973237fead6SMichael Halcrow rc = write_packet_length(&dest[(*packet_size)], 974237fead6SMichael Halcrow (0x05 + ECRYPTFS_SALT_SIZE 975237fead6SMichael Halcrow + (*key_rec).enc_key_size), 976237fead6SMichael Halcrow &packet_size_length); 977237fead6SMichael Halcrow if (rc) { 978237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error generating tag 3 packet " 979237fead6SMichael Halcrow "header; cannot generate packet length\n"); 980237fead6SMichael Halcrow goto out; 981237fead6SMichael Halcrow } 982237fead6SMichael Halcrow (*packet_size) += packet_size_length; 983237fead6SMichael Halcrow dest[(*packet_size)++] = 0x04; /* version 4 */ 984237fead6SMichael Halcrow cipher_code = ecryptfs_code_for_cipher_string(crypt_stat); 985237fead6SMichael Halcrow if (cipher_code == 0) { 986237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Unable to generate code for " 987237fead6SMichael Halcrow "cipher [%s]\n", crypt_stat->cipher); 988237fead6SMichael Halcrow rc = -EINVAL; 989237fead6SMichael Halcrow goto out; 990237fead6SMichael Halcrow } 991237fead6SMichael Halcrow dest[(*packet_size)++] = cipher_code; 992237fead6SMichael Halcrow dest[(*packet_size)++] = 0x03; /* S2K */ 993237fead6SMichael Halcrow dest[(*packet_size)++] = 0x01; /* MD5 (TODO: parameterize) */ 994237fead6SMichael Halcrow memcpy(&dest[(*packet_size)], auth_tok->token.password.salt, 995237fead6SMichael Halcrow ECRYPTFS_SALT_SIZE); 996237fead6SMichael Halcrow (*packet_size) += ECRYPTFS_SALT_SIZE; /* salt */ 997237fead6SMichael Halcrow dest[(*packet_size)++] = 0x60; /* hash iterations (65536) */ 998237fead6SMichael Halcrow memcpy(&dest[(*packet_size)], (*key_rec).enc_key, 999237fead6SMichael Halcrow (*key_rec).enc_key_size); 1000237fead6SMichael Halcrow (*packet_size) += (*key_rec).enc_key_size; 1001237fead6SMichael Halcrow out: 10028bba066fSMichael Halcrow if (desc.tfm && !tfm_mutex) 10038bba066fSMichael Halcrow crypto_free_blkcipher(desc.tfm); 1004237fead6SMichael Halcrow if (rc) 1005237fead6SMichael Halcrow (*packet_size) = 0; 1006237fead6SMichael Halcrow return rc; 1007237fead6SMichael Halcrow } 1008237fead6SMichael Halcrow 1009237fead6SMichael Halcrow /** 1010237fead6SMichael Halcrow * ecryptfs_generate_key_packet_set 1011237fead6SMichael Halcrow * @dest: Virtual address from which to write the key record set 1012237fead6SMichael Halcrow * @crypt_stat: The cryptographic context from which the 1013237fead6SMichael Halcrow * authentication tokens will be retrieved 1014237fead6SMichael Halcrow * @ecryptfs_dentry: The dentry, used to retrieve the mount crypt stat 1015237fead6SMichael Halcrow * for the global parameters 1016237fead6SMichael Halcrow * @len: The amount written 1017237fead6SMichael Halcrow * @max: The maximum amount of data allowed to be written 1018237fead6SMichael Halcrow * 1019237fead6SMichael Halcrow * Generates a key packet set and writes it to the virtual address 1020237fead6SMichael Halcrow * passed in. 1021237fead6SMichael Halcrow * 1022237fead6SMichael Halcrow * Returns zero on success; non-zero on error. 1023237fead6SMichael Halcrow */ 1024237fead6SMichael Halcrow int 1025237fead6SMichael Halcrow ecryptfs_generate_key_packet_set(char *dest_base, 1026237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat, 1027237fead6SMichael Halcrow struct dentry *ecryptfs_dentry, size_t *len, 1028237fead6SMichael Halcrow size_t max) 1029237fead6SMichael Halcrow { 1030237fead6SMichael Halcrow int rc = 0; 1031237fead6SMichael Halcrow struct ecryptfs_auth_tok *auth_tok; 1032237fead6SMichael Halcrow struct ecryptfs_mount_crypt_stat *mount_crypt_stat = 1033237fead6SMichael Halcrow &ecryptfs_superblock_to_private( 1034237fead6SMichael Halcrow ecryptfs_dentry->d_sb)->mount_crypt_stat; 1035237fead6SMichael Halcrow size_t written; 1036237fead6SMichael Halcrow struct ecryptfs_key_record key_rec; 1037237fead6SMichael Halcrow 1038237fead6SMichael Halcrow (*len) = 0; 1039237fead6SMichael Halcrow if (mount_crypt_stat->global_auth_tok) { 1040237fead6SMichael Halcrow auth_tok = mount_crypt_stat->global_auth_tok; 1041237fead6SMichael Halcrow if (auth_tok->token_type == ECRYPTFS_PASSWORD) { 1042237fead6SMichael Halcrow rc = write_tag_3_packet((dest_base + (*len)), 1043237fead6SMichael Halcrow max, auth_tok, 1044237fead6SMichael Halcrow crypt_stat, &key_rec, 1045237fead6SMichael Halcrow &written); 1046237fead6SMichael Halcrow if (rc) { 1047237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Error " 1048237fead6SMichael Halcrow "writing tag 3 packet\n"); 1049237fead6SMichael Halcrow goto out; 1050237fead6SMichael Halcrow } 1051237fead6SMichael Halcrow (*len) += written; 1052237fead6SMichael Halcrow /* Write auth tok signature packet */ 1053237fead6SMichael Halcrow rc = write_tag_11_packet( 1054237fead6SMichael Halcrow (dest_base + (*len)), 1055237fead6SMichael Halcrow (max - (*len)), 1056237fead6SMichael Halcrow key_rec.sig, ECRYPTFS_SIG_SIZE, &written); 1057237fead6SMichael Halcrow if (rc) { 1058237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error writing " 1059237fead6SMichael Halcrow "auth tok signature packet\n"); 1060237fead6SMichael Halcrow goto out; 1061237fead6SMichael Halcrow } 1062237fead6SMichael Halcrow (*len) += written; 1063237fead6SMichael Halcrow } else { 1064237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Unsupported " 1065237fead6SMichael Halcrow "authentication token type\n"); 1066237fead6SMichael Halcrow rc = -EINVAL; 1067237fead6SMichael Halcrow goto out; 1068237fead6SMichael Halcrow } 1069237fead6SMichael Halcrow if (rc) { 1070237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Error writing " 1071237fead6SMichael Halcrow "authentication token packet with sig " 1072237fead6SMichael Halcrow "= [%s]\n", 1073237fead6SMichael Halcrow mount_crypt_stat->global_auth_tok_sig); 1074237fead6SMichael Halcrow rc = -EIO; 1075237fead6SMichael Halcrow goto out; 1076237fead6SMichael Halcrow } 1077237fead6SMichael Halcrow } else 1078237fead6SMichael Halcrow BUG(); 1079237fead6SMichael Halcrow if (likely((max - (*len)) > 0)) { 1080237fead6SMichael Halcrow dest_base[(*len)] = 0x00; 1081237fead6SMichael Halcrow } else { 1082237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error writing boundary byte\n"); 1083237fead6SMichael Halcrow rc = -EIO; 1084237fead6SMichael Halcrow } 1085237fead6SMichael Halcrow out: 1086237fead6SMichael Halcrow if (rc) 1087237fead6SMichael Halcrow (*len) = 0; 1088237fead6SMichael Halcrow return rc; 1089237fead6SMichael Halcrow } 1090