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687db64c567b4529aa723a8f5f87946f7cde4cd5
heimdal/lib/krb5/crypto.c
Love Hornquist Astrand 687db64c56 Patch from Secure Endpoints/Asanka Herath for windows support
2009-12-21 08:45:28 +01:00

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/*
* Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#define KRB5_DEPRECATED
#include "krb5_locl.h"
#include <pkinit_asn1.h>
#ifndef HEIMDAL_SMALLER
#define DES3_OLD_ENCTYPE 1
#endif
struct key_data {
krb5_keyblock *key;
krb5_data *schedule;
};
struct key_usage {
unsigned usage;
struct key_data key;
};
struct krb5_crypto_data {
struct encryption_type *et;
struct key_data key;
int num_key_usage;
struct key_usage *key_usage;
};
#define CRYPTO_ETYPE(C) ((C)->et->type)
/* bits for `flags' below */
#define F_KEYED 1 /* checksum is keyed */
#define F_CPROOF 2 /* checksum is collision proof */
#define F_DERIVED 4 /* uses derived keys */
#define F_VARIANT 8 /* uses `variant' keys (6.4.3) */
#define F_PSEUDO 16 /* not a real protocol type */
#define F_SPECIAL 32 /* backwards */
#define F_DISABLED 64 /* enctype/checksum disabled */
struct salt_type {
krb5_salttype type;
const char *name;
krb5_error_code (*string_to_key)(krb5_context, krb5_enctype, krb5_data,
krb5_salt, krb5_data, krb5_keyblock*);
};
struct key_type {
krb5_keytype type; /* XXX */
const char *name;
size_t bits;
size_t size;
size_t schedule_size;
void (*random_key)(krb5_context, krb5_keyblock*);
void (*schedule)(krb5_context, struct key_type *, struct key_data *);
struct salt_type *string_to_key;
void (*random_to_key)(krb5_context, krb5_keyblock*, const void*, size_t);
void (*cleanup)(krb5_context, struct key_data *);
const EVP_CIPHER *(*evp)(void);
};
struct checksum_type {
krb5_cksumtype type;
const char *name;
size_t blocksize;
size_t checksumsize;
unsigned flags;
krb5_enctype (*checksum)(krb5_context context,
struct key_data *key,
const void *buf, size_t len,
unsigned usage,
Checksum *csum);
krb5_error_code (*verify)(krb5_context context,
struct key_data *key,
const void *buf, size_t len,
unsigned usage,
Checksum *csum);
};
struct encryption_type {
krb5_enctype type;
const char *name;
size_t blocksize;
size_t padsize;
size_t confoundersize;
struct key_type *keytype;
struct checksum_type *checksum;
struct checksum_type *keyed_checksum;
unsigned flags;
krb5_error_code (*encrypt)(krb5_context context,
struct key_data *key,
void *data, size_t len,
krb5_boolean encryptp,
int usage,
void *ivec);
size_t prf_length;
krb5_error_code (*prf)(krb5_context,
krb5_crypto, const krb5_data *, krb5_data *);
};
#define ENCRYPTION_USAGE(U) (((U) << 8) | 0xAA)
#define INTEGRITY_USAGE(U) (((U) << 8) | 0x55)
#define CHECKSUM_USAGE(U) (((U) << 8) | 0x99)
static struct checksum_type *_find_checksum(krb5_cksumtype type);
static struct encryption_type *_find_enctype(krb5_enctype type);
static krb5_error_code _get_derived_key(krb5_context, krb5_crypto,
unsigned, struct key_data**);
static struct key_data *_new_derived_key(krb5_crypto crypto, unsigned usage);
static krb5_error_code derive_key(krb5_context context,
struct encryption_type *et,
struct key_data *key,
const void *constant,
size_t len);
static krb5_error_code hmac(krb5_context context,
struct checksum_type *cm,
const void *data,
size_t len,
unsigned usage,
struct key_data *keyblock,
Checksum *result);
static void free_key_data(krb5_context,
struct key_data *,
struct encryption_type *);
static void free_key_schedule(krb5_context,
struct key_data *,
struct encryption_type *);
static krb5_error_code usage2arcfour (krb5_context, unsigned *);
static void xor (DES_cblock *, const unsigned char *);
/************************************************************
* *
************************************************************/
struct evp_schedule {
EVP_CIPHER_CTX ectx;
EVP_CIPHER_CTX dctx;
};
static HEIMDAL_MUTEX crypto_mutex = HEIMDAL_MUTEX_INITIALIZER;
#ifdef HEIM_WEAK_CRYPTO
static void
krb5_DES_random_key(krb5_context context,
krb5_keyblock *key)
{
DES_cblock *k = key->keyvalue.data;
do {
krb5_generate_random_block(k, sizeof(DES_cblock));
DES_set_odd_parity(k);
} while(DES_is_weak_key(k));
}
static void
krb5_DES_schedule_old(krb5_context context,
struct key_type *kt,
struct key_data *key)
{
DES_set_key_unchecked(key->key->keyvalue.data, key->schedule->data);
}
#ifdef ENABLE_AFS_STRING_TO_KEY
/* This defines the Andrew string_to_key function. It accepts a password
* string as input and converts it via a one-way encryption algorithm to a DES
* encryption key. It is compatible with the original Andrew authentication
* service password database.
*/
/*
* Short passwords, i.e 8 characters or less.
*/
static void
krb5_DES_AFS3_CMU_string_to_key (krb5_data pw,
krb5_data cell,
DES_cblock *key)
{
char password[8+1]; /* crypt is limited to 8 chars anyway */
int i;
for(i = 0; i < 8; i++) {
char c = ((i < pw.length) ? ((char*)pw.data)[i] : 0) ^
((i < cell.length) ?
tolower(((unsigned char*)cell.data)[i]) : 0);
password[i] = c ? c : 'X';
}
password[8] = '\0';
memcpy(key, crypt(password, "p1") + 2, sizeof(DES_cblock));
/* parity is inserted into the LSB so left shift each byte up one
bit. This allows ascii characters with a zero MSB to retain as
much significance as possible. */
for (i = 0; i < sizeof(DES_cblock); i++)
((unsigned char*)key)[i] <<= 1;
DES_set_odd_parity (key);
}
/*
* Long passwords, i.e 9 characters or more.
*/
static void
krb5_DES_AFS3_Transarc_string_to_key (krb5_data pw,
krb5_data cell,
DES_cblock *key)
{
DES_key_schedule schedule;
DES_cblock temp_key;
DES_cblock ivec;
char password[512];
size_t passlen;
memcpy(password, pw.data, min(pw.length, sizeof(password)));
if(pw.length < sizeof(password)) {
int len = min(cell.length, sizeof(password) - pw.length);
int i;
memcpy(password + pw.length, cell.data, len);
for (i = pw.length; i < pw.length + len; ++i)
password[i] = tolower((unsigned char)password[i]);
}
passlen = min(sizeof(password), pw.length + cell.length);
memcpy(&ivec, "kerberos", 8);
memcpy(&temp_key, "kerberos", 8);
DES_set_odd_parity (&temp_key);
DES_set_key_unchecked (&temp_key, &schedule);
DES_cbc_cksum ((void*)password, &ivec, passlen, &schedule, &ivec);
memcpy(&temp_key, &ivec, 8);
DES_set_odd_parity (&temp_key);
DES_set_key_unchecked (&temp_key, &schedule);
DES_cbc_cksum ((void*)password, key, passlen, &schedule, &ivec);
memset(&schedule, 0, sizeof(schedule));
memset(&temp_key, 0, sizeof(temp_key));
memset(&ivec, 0, sizeof(ivec));
memset(password, 0, sizeof(password));
DES_set_odd_parity (key);
}
static krb5_error_code
DES_AFS3_string_to_key(krb5_context context,
krb5_enctype enctype,
krb5_data password,
krb5_salt salt,
krb5_data opaque,
krb5_keyblock *key)
{
DES_cblock tmp;
if(password.length > 8)
krb5_DES_AFS3_Transarc_string_to_key(password, salt.saltvalue, &tmp);
else
krb5_DES_AFS3_CMU_string_to_key(password, salt.saltvalue, &tmp);
key->keytype = enctype;
krb5_data_copy(&key->keyvalue, tmp, sizeof(tmp));
memset(&key, 0, sizeof(key));
return 0;
}
#endif /* ENABLE_AFS_STRING_TO_KEY */
static void
DES_string_to_key_int(unsigned char *data, size_t length, DES_cblock *key)
{
DES_key_schedule schedule;
int i;
int reverse = 0;
unsigned char *p;
unsigned char swap[] = { 0x0, 0x8, 0x4, 0xc, 0x2, 0xa, 0x6, 0xe,
0x1, 0x9, 0x5, 0xd, 0x3, 0xb, 0x7, 0xf };
memset(key, 0, 8);
p = (unsigned char*)key;
for (i = 0; i < length; i++) {
unsigned char tmp = data[i];
if (!reverse)
*p++ ^= (tmp << 1);
else
*--p ^= (swap[tmp & 0xf] << 4) | swap[(tmp & 0xf0) >> 4];
if((i % 8) == 7)
reverse = !reverse;
}
DES_set_odd_parity(key);
if(DES_is_weak_key(key))
(*key)[7] ^= 0xF0;
DES_set_key_unchecked(key, &schedule);
DES_cbc_cksum((void*)data, key, length, &schedule, key);
memset(&schedule, 0, sizeof(schedule));
DES_set_odd_parity(key);
if(DES_is_weak_key(key))
(*key)[7] ^= 0xF0;
}
static krb5_error_code
krb5_DES_string_to_key(krb5_context context,
krb5_enctype enctype,
krb5_data password,
krb5_salt salt,
krb5_data opaque,
krb5_keyblock *key)
{
unsigned char *s;
size_t len;
DES_cblock tmp;
#ifdef ENABLE_AFS_STRING_TO_KEY
if (opaque.length == 1) {
unsigned long v;
_krb5_get_int(opaque.data, &v, 1);
if (v == 1)
return DES_AFS3_string_to_key(context, enctype, password,
salt, opaque, key);
}
#endif
len = password.length + salt.saltvalue.length;
s = malloc(len);
if(len > 0 && s == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
memcpy(s, password.data, password.length);
memcpy(s + password.length, salt.saltvalue.data, salt.saltvalue.length);
DES_string_to_key_int(s, len, &tmp);
key->keytype = enctype;
krb5_data_copy(&key->keyvalue, tmp, sizeof(tmp));
memset(&tmp, 0, sizeof(tmp));
memset(s, 0, len);
free(s);
return 0;
}
static void
krb5_DES_random_to_key(krb5_context context,
krb5_keyblock *key,
const void *data,
size_t size)
{
DES_cblock *k = key->keyvalue.data;
memcpy(k, data, key->keyvalue.length);
DES_set_odd_parity(k);
if(DES_is_weak_key(k))
xor(k, (const unsigned char*)"\0\0\0\0\0\0\0\xf0");
}
#endif
/*
*
*/
static void
DES3_random_key(krb5_context context,
krb5_keyblock *key)
{
DES_cblock *k = key->keyvalue.data;
do {
krb5_generate_random_block(k, 3 * sizeof(DES_cblock));
DES_set_odd_parity(&k[0]);
DES_set_odd_parity(&k[1]);
DES_set_odd_parity(&k[2]);
} while(DES_is_weak_key(&k[0]) ||
DES_is_weak_key(&k[1]) ||
DES_is_weak_key(&k[2]));
}
/*
* A = A xor B. A & B are 8 bytes.
*/
static void
xor (DES_cblock *key, const unsigned char *b)
{
unsigned char *a = (unsigned char*)key;
a[0] ^= b[0];
a[1] ^= b[1];
a[2] ^= b[2];
a[3] ^= b[3];
a[4] ^= b[4];
a[5] ^= b[5];
a[6] ^= b[6];
a[7] ^= b[7];
}
#ifdef DES3_OLD_ENCTYPE
static krb5_error_code
DES3_string_to_key(krb5_context context,
krb5_enctype enctype,
krb5_data password,
krb5_salt salt,
krb5_data opaque,
krb5_keyblock *key)
{
char *str;
size_t len;
unsigned char tmp[24];
DES_cblock keys[3];
krb5_error_code ret;
len = password.length + salt.saltvalue.length;
str = malloc(len);
if(len != 0 && str == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
memcpy(str, password.data, password.length);
memcpy(str + password.length, salt.saltvalue.data, salt.saltvalue.length);
{
DES_cblock ivec;
DES_key_schedule s[3];
int i;
ret = _krb5_n_fold(str, len, tmp, 24);
if (ret) {
memset(str, 0, len);
free(str);
krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
return ret;
}
for(i = 0; i < 3; i++){
memcpy(keys + i, tmp + i * 8, sizeof(keys[i]));
DES_set_odd_parity(keys + i);
if(DES_is_weak_key(keys + i))
xor(keys + i, (const unsigned char*)"\0\0\0\0\0\0\0\xf0");
DES_set_key_unchecked(keys + i, &s[i]);
}
memset(&ivec, 0, sizeof(ivec));
DES_ede3_cbc_encrypt(tmp,
tmp, sizeof(tmp),
&s[0], &s[1], &s[2], &ivec, DES_ENCRYPT);
memset(s, 0, sizeof(s));
memset(&ivec, 0, sizeof(ivec));
for(i = 0; i < 3; i++){
memcpy(keys + i, tmp + i * 8, sizeof(keys[i]));
DES_set_odd_parity(keys + i);
if(DES_is_weak_key(keys + i))
xor(keys + i, (const unsigned char*)"\0\0\0\0\0\0\0\xf0");
}
memset(tmp, 0, sizeof(tmp));
}
key->keytype = enctype;
krb5_data_copy(&key->keyvalue, keys, sizeof(keys));
memset(keys, 0, sizeof(keys));
memset(str, 0, len);
free(str);
return 0;
}
#endif
static krb5_error_code
DES3_string_to_key_derived(krb5_context context,
krb5_enctype enctype,
krb5_data password,
krb5_salt salt,
krb5_data opaque,
krb5_keyblock *key)
{
krb5_error_code ret;
size_t len = password.length + salt.saltvalue.length;
char *s;
s = malloc(len);
if(len != 0 && s == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
memcpy(s, password.data, password.length);
memcpy(s + password.length, salt.saltvalue.data, salt.saltvalue.length);
ret = krb5_string_to_key_derived(context,
s,
len,
enctype,
key);
memset(s, 0, len);
free(s);
return ret;
}
static void
DES3_random_to_key(krb5_context context,
krb5_keyblock *key,
const void *data,
size_t size)
{
unsigned char *x = key->keyvalue.data;
const u_char *q = data;
DES_cblock *k;
int i, j;
memset(x, 0, sizeof(x));
for (i = 0; i < 3; ++i) {
unsigned char foo;
for (j = 0; j < 7; ++j) {
unsigned char b = q[7 * i + j];
x[8 * i + j] = b;
}
foo = 0;
for (j = 6; j >= 0; --j) {
foo |= q[7 * i + j] & 1;
foo <<= 1;
}
x[8 * i + 7] = foo;
}
k = key->keyvalue.data;
for (i = 0; i < 3; i++) {
DES_set_odd_parity(&k[i]);
if(DES_is_weak_key(&k[i]))
xor(&k[i], (const unsigned char*)"\0\0\0\0\0\0\0\xf0");
}
}
/*
* ARCFOUR
*/
static krb5_error_code
ARCFOUR_string_to_key(krb5_context context,
krb5_enctype enctype,
krb5_data password,
krb5_salt salt,
krb5_data opaque,
krb5_keyblock *key)
{
krb5_error_code ret;
uint16_t *s = NULL;
size_t len, i;
EVP_MD_CTX *m;
m = EVP_MD_CTX_create();
if (m == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
goto out;
}
EVP_DigestInit_ex(m, EVP_md4(), NULL);
ret = wind_utf8ucs2_length(password.data, &len);
if (ret) {
krb5_set_error_message (context, ret,
N_("Password not an UCS2 string", ""));
goto out;
}
s = malloc (len * sizeof(s[0]));
if (len != 0 && s == NULL) {
krb5_set_error_message (context, ENOMEM,
N_("malloc: out of memory", ""));
ret = ENOMEM;
goto out;
}
ret = wind_utf8ucs2(password.data, s, &len);
if (ret) {
krb5_set_error_message (context, ret,
N_("Password not an UCS2 string", ""));
goto out;
}
/* LE encoding */
for (i = 0; i < len; i++) {
unsigned char p;
p = (s[i] & 0xff);
EVP_DigestUpdate (m, &p, 1);
p = (s[i] >> 8) & 0xff;
EVP_DigestUpdate (m, &p, 1);
}
key->keytype = enctype;
ret = krb5_data_alloc (&key->keyvalue, 16);
if (ret) {
krb5_set_error_message (context, ENOMEM, N_("malloc: out of memory", ""));
goto out;
}
EVP_DigestFinal_ex (m, key->keyvalue.data, NULL);
out:
EVP_MD_CTX_destroy(m);
if (s)
memset (s, 0, len);
free (s);
return ret;
}
/*
* AES
*/
int _krb5_AES_string_to_default_iterator = 4096;
static krb5_error_code
AES_string_to_key(krb5_context context,
krb5_enctype enctype,
krb5_data password,
krb5_salt salt,
krb5_data opaque,
krb5_keyblock *key)
{
krb5_error_code ret;
uint32_t iter;
struct encryption_type *et;
struct key_data kd;
if (opaque.length == 0)
iter = _krb5_AES_string_to_default_iterator;
else if (opaque.length == 4) {
unsigned long v;
_krb5_get_int(opaque.data, &v, 4);
iter = ((uint32_t)v);
} else
return KRB5_PROG_KEYTYPE_NOSUPP; /* XXX */
et = _find_enctype(enctype);
if (et == NULL)
return KRB5_PROG_KEYTYPE_NOSUPP;
kd.schedule = NULL;
ALLOC(kd.key, 1);
if(kd.key == NULL) {
krb5_set_error_message (context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
kd.key->keytype = enctype;
ret = krb5_data_alloc(&kd.key->keyvalue, et->keytype->size);
if (ret) {
krb5_set_error_message (context, ret, N_("malloc: out of memory", ""));
return ret;
}
ret = PKCS5_PBKDF2_HMAC_SHA1(password.data, password.length,
salt.saltvalue.data, salt.saltvalue.length,
iter,
et->keytype->size, kd.key->keyvalue.data);
if (ret != 1) {
free_key_data(context, &kd, et);
krb5_set_error_message(context, KRB5_PROG_KEYTYPE_NOSUPP,
"Error calculating s2k");
return KRB5_PROG_KEYTYPE_NOSUPP;
}
ret = derive_key(context, et, &kd, "kerberos", strlen("kerberos"));
if (ret == 0)
ret = krb5_copy_keyblock_contents(context, kd.key, key);
free_key_data(context, &kd, et);
return ret;
}
static void
evp_schedule(krb5_context context, struct key_type *kt, struct key_data *kd)
{
struct evp_schedule *key = kd->schedule->data;
const EVP_CIPHER *c = (*kt->evp)();
EVP_CIPHER_CTX_init(&key->ectx);
EVP_CIPHER_CTX_init(&key->dctx);
EVP_CipherInit_ex(&key->ectx, c, NULL, kd->key->keyvalue.data, NULL, 1);
EVP_CipherInit_ex(&key->dctx, c, NULL, kd->key->keyvalue.data, NULL, 0);
}
static void
evp_cleanup(krb5_context context, struct key_data *kd)
{
struct evp_schedule *key = kd->schedule->data;
EVP_CIPHER_CTX_cleanup(&key->ectx);
EVP_CIPHER_CTX_cleanup(&key->dctx);
}
/*
*
*/
#ifdef HEIM_WEAK_CRYPTO
static struct salt_type des_salt[] = {
{
KRB5_PW_SALT,
"pw-salt",
krb5_DES_string_to_key
},
#ifdef ENABLE_AFS_STRING_TO_KEY
{
KRB5_AFS3_SALT,
"afs3-salt",
DES_AFS3_string_to_key
},
#endif
{ 0 }
};
#endif
#ifdef DES3_OLD_ENCTYPE
static struct salt_type des3_salt[] = {
{
KRB5_PW_SALT,
"pw-salt",
DES3_string_to_key
},
{ 0 }
};
#endif
static struct salt_type des3_salt_derived[] = {
{
KRB5_PW_SALT,
"pw-salt",
DES3_string_to_key_derived
},
{ 0 }
};
static struct salt_type AES_salt[] = {
{
KRB5_PW_SALT,
"pw-salt",
AES_string_to_key
},
{ 0 }
};
static struct salt_type arcfour_salt[] = {
{
KRB5_PW_SALT,
"pw-salt",
ARCFOUR_string_to_key
},
{ 0 }
};
/*
*
*/
static struct key_type keytype_null = {
KEYTYPE_NULL,
"null",
0,
0,
0,
NULL,
NULL,
NULL
};
#ifdef HEIM_WEAK_CRYPTO
static struct key_type keytype_des_old = {
KEYTYPE_DES,
"des-old",
56,
8,
sizeof(DES_key_schedule),
krb5_DES_random_key,
krb5_DES_schedule_old,
des_salt,
krb5_DES_random_to_key
};
static struct key_type keytype_des = {
KEYTYPE_DES,
"des",
56,
8,
sizeof(struct evp_schedule),
krb5_DES_random_key,
evp_schedule,
des_salt,
krb5_DES_random_to_key,
evp_cleanup,
EVP_des_cbc
};
#endif /* HEIM_WEAK_CRYPTO */
#ifdef DES3_OLD_ENCTYPE
static struct key_type keytype_des3 = {
KEYTYPE_DES3,
"des3",
168,
24,
sizeof(struct evp_schedule),
DES3_random_key,
evp_schedule,
des3_salt,
DES3_random_to_key,
evp_cleanup,
EVP_des_ede3_cbc
};
#endif
static struct key_type keytype_des3_derived = {
KEYTYPE_DES3,
"des3",
168,
24,
sizeof(struct evp_schedule),
DES3_random_key,
evp_schedule,
des3_salt_derived,
DES3_random_to_key,
evp_cleanup,
EVP_des_ede3_cbc
};
static struct key_type keytype_aes128 = {
KEYTYPE_AES128,
"aes-128",
128,
16,
sizeof(struct evp_schedule),
NULL,
evp_schedule,
AES_salt,
NULL,
evp_cleanup,
EVP_aes_128_cbc
};
static struct key_type keytype_aes256 = {
KEYTYPE_AES256,
"aes-256",
256,
32,
sizeof(struct evp_schedule),
NULL,
evp_schedule,
AES_salt,
NULL,
evp_cleanup,
EVP_aes_256_cbc
};
static struct key_type keytype_arcfour = {
KEYTYPE_ARCFOUR,
"arcfour",
128,
16,
sizeof(struct evp_schedule),
NULL,
evp_schedule,
arcfour_salt,
NULL,
evp_cleanup,
EVP_rc4
};
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_salttype_to_string (krb5_context context,
krb5_enctype etype,
krb5_salttype stype,
char **string)
{
struct encryption_type *e;
struct salt_type *st;
e = _find_enctype (etype);
if (e == NULL) {
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
"encryption type %d not supported",
etype);
return KRB5_PROG_ETYPE_NOSUPP;
}
for (st = e->keytype->string_to_key; st && st->type; st++) {
if (st->type == stype) {
*string = strdup (st->name);
if (*string == NULL) {
krb5_set_error_message (context, ENOMEM,
N_("malloc: out of memory", ""));
return ENOMEM;
}
return 0;
}
}
krb5_set_error_message (context, HEIM_ERR_SALTTYPE_NOSUPP,
"salttype %d not supported", stype);
return HEIM_ERR_SALTTYPE_NOSUPP;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_string_to_salttype (krb5_context context,
krb5_enctype etype,
const char *string,
krb5_salttype *salttype)
{
struct encryption_type *e;
struct salt_type *st;
e = _find_enctype (etype);
if (e == NULL) {
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
etype);
return KRB5_PROG_ETYPE_NOSUPP;
}
for (st = e->keytype->string_to_key; st && st->type; st++) {
if (strcasecmp (st->name, string) == 0) {
*salttype = st->type;
return 0;
}
}
krb5_set_error_message(context, HEIM_ERR_SALTTYPE_NOSUPP,
N_("salttype %s not supported", ""), string);
return HEIM_ERR_SALTTYPE_NOSUPP;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_get_pw_salt(krb5_context context,
krb5_const_principal principal,
krb5_salt *salt)
{
size_t len;
int i;
krb5_error_code ret;
char *p;
salt->salttype = KRB5_PW_SALT;
len = strlen(principal->realm);
for (i = 0; i < principal->name.name_string.len; ++i)
len += strlen(principal->name.name_string.val[i]);
ret = krb5_data_alloc (&salt->saltvalue, len);
if (ret)
return ret;
p = salt->saltvalue.data;
memcpy (p, principal->realm, strlen(principal->realm));
p += strlen(principal->realm);
for (i = 0; i < principal->name.name_string.len; ++i) {
memcpy (p,
principal->name.name_string.val[i],
strlen(principal->name.name_string.val[i]));
p += strlen(principal->name.name_string.val[i]);
}
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_free_salt(krb5_context context,
krb5_salt salt)
{
krb5_data_free(&salt.saltvalue);
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_string_to_key_data (krb5_context context,
krb5_enctype enctype,
krb5_data password,
krb5_principal principal,
krb5_keyblock *key)
{
krb5_error_code ret;
krb5_salt salt;
ret = krb5_get_pw_salt(context, principal, &salt);
if(ret)
return ret;
ret = krb5_string_to_key_data_salt(context, enctype, password, salt, key);
krb5_free_salt(context, salt);
return ret;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_string_to_key (krb5_context context,
krb5_enctype enctype,
const char *password,
krb5_principal principal,
krb5_keyblock *key)
{
krb5_data pw;
pw.data = rk_UNCONST(password);
pw.length = strlen(password);
return krb5_string_to_key_data(context, enctype, pw, principal, key);
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_string_to_key_data_salt (krb5_context context,
krb5_enctype enctype,
krb5_data password,
krb5_salt salt,
krb5_keyblock *key)
{
krb5_data opaque;
krb5_data_zero(&opaque);
return krb5_string_to_key_data_salt_opaque(context, enctype, password,
salt, opaque, key);
}
/*
* Do a string -> key for encryption type `enctype' operation on
* `password' (with salt `salt' and the enctype specific data string
* `opaque'), returning the resulting key in `key'
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_string_to_key_data_salt_opaque (krb5_context context,
krb5_enctype enctype,
krb5_data password,
krb5_salt salt,
krb5_data opaque,
krb5_keyblock *key)
{
struct encryption_type *et =_find_enctype(enctype);
struct salt_type *st;
if(et == NULL) {
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
enctype);
return KRB5_PROG_ETYPE_NOSUPP;
}
for(st = et->keytype->string_to_key; st && st->type; st++)
if(st->type == salt.salttype)
return (*st->string_to_key)(context, enctype, password,
salt, opaque, key);
krb5_set_error_message(context, HEIM_ERR_SALTTYPE_NOSUPP,
N_("salt type %d not supported", ""),
salt.salttype);
return HEIM_ERR_SALTTYPE_NOSUPP;
}
/*
* Do a string -> key for encryption type `enctype' operation on the
* string `password' (with salt `salt'), returning the resulting key
* in `key'
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_string_to_key_salt (krb5_context context,
krb5_enctype enctype,
const char *password,
krb5_salt salt,
krb5_keyblock *key)
{
krb5_data pw;
pw.data = rk_UNCONST(password);
pw.length = strlen(password);
return krb5_string_to_key_data_salt(context, enctype, pw, salt, key);
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_string_to_key_salt_opaque (krb5_context context,
krb5_enctype enctype,
const char *password,
krb5_salt salt,
krb5_data opaque,
krb5_keyblock *key)
{
krb5_data pw;
pw.data = rk_UNCONST(password);
pw.length = strlen(password);
return krb5_string_to_key_data_salt_opaque(context, enctype,
pw, salt, opaque, key);
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_enctype_keysize(krb5_context context,
krb5_enctype type,
size_t *keysize)
{
struct encryption_type *et = _find_enctype(type);
if(et == NULL) {
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
type);
return KRB5_PROG_ETYPE_NOSUPP;
}
*keysize = et->keytype->size;
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_enctype_keybits(krb5_context context,
krb5_enctype type,
size_t *keybits)
{
struct encryption_type *et = _find_enctype(type);
if(et == NULL) {
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
"encryption type %d not supported",
type);
return KRB5_PROG_ETYPE_NOSUPP;
}
*keybits = et->keytype->bits;
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_generate_random_keyblock(krb5_context context,
krb5_enctype type,
krb5_keyblock *key)
{
krb5_error_code ret;
struct encryption_type *et = _find_enctype(type);
if(et == NULL) {
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
type);
return KRB5_PROG_ETYPE_NOSUPP;
}
ret = krb5_data_alloc(&key->keyvalue, et->keytype->size);
if(ret)
return ret;
key->keytype = type;
if(et->keytype->random_key)
(*et->keytype->random_key)(context, key);
else
krb5_generate_random_block(key->keyvalue.data,
key->keyvalue.length);
return 0;
}
static krb5_error_code
_key_schedule(krb5_context context,
struct key_data *key)
{
krb5_error_code ret;
struct encryption_type *et = _find_enctype(key->key->keytype);
struct key_type *kt;
if (et == NULL) {
krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
key->key->keytype);
return KRB5_PROG_ETYPE_NOSUPP;
}
kt = et->keytype;
if(kt->schedule == NULL)
return 0;
if (key->schedule != NULL)
return 0;
ALLOC(key->schedule, 1);
if(key->schedule == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
ret = krb5_data_alloc(key->schedule, kt->schedule_size);
if(ret) {
free(key->schedule);
key->schedule = NULL;
return ret;
}
(*kt->schedule)(context, kt, key);
return 0;
}
/************************************************************
* *
************************************************************/
static krb5_error_code
NONE_checksum(krb5_context context,
struct key_data *key,
const void *data,
size_t len,
unsigned usage,
Checksum *C)
{
return 0;
}
#if defined(DES3_OLD_ENCTYPE) || defined(HEIM_WEAK_CRYPTO)
static krb5_error_code
des_checksum(krb5_context context,
const EVP_MD *evp_md,
struct key_data *key,
const void *data,
size_t len,
Checksum *cksum)
{
struct evp_schedule *ctx = key->schedule->data;
EVP_MD_CTX *m;
DES_cblock ivec;
unsigned char *p = cksum->checksum.data;
krb5_generate_random_block(p, 8);
m = EVP_MD_CTX_create();
if (m == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
EVP_DigestInit_ex(m, evp_md, NULL);
EVP_DigestUpdate(m, p, 8);
EVP_DigestUpdate(m, data, len);
EVP_DigestFinal_ex (m, p + 8, NULL);
EVP_MD_CTX_destroy(m);
memset (&ivec, 0, sizeof(ivec));
EVP_CipherInit_ex(&ctx->ectx, NULL, NULL, NULL, (void *)&ivec, -1);
EVP_Cipher(&ctx->ectx, p, p, 24);
return 0;
}
static krb5_error_code
des_verify(krb5_context context,
const EVP_MD *evp_md,
struct key_data *key,
const void *data,
size_t len,
Checksum *C)
{
struct evp_schedule *ctx = key->schedule->data;
EVP_MD_CTX *m;
unsigned char tmp[24];
unsigned char res[16];
DES_cblock ivec;
krb5_error_code ret = 0;
m = EVP_MD_CTX_create();
if (m == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
memset(&ivec, 0, sizeof(ivec));
EVP_CipherInit_ex(&ctx->dctx, NULL, NULL, NULL, (void *)&ivec, -1);
EVP_Cipher(&ctx->dctx, tmp, C->checksum.data, 24);
EVP_DigestInit_ex(m, evp_md, NULL);
EVP_DigestUpdate(m, tmp, 8); /* confounder */
EVP_DigestUpdate(m, data, len);
EVP_DigestFinal_ex (m, res, NULL);
EVP_MD_CTX_destroy(m);
if(ct_memcmp(res, tmp + 8, sizeof(res)) != 0) {
krb5_clear_error_message (context);
ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
}
memset(tmp, 0, sizeof(tmp));
memset(res, 0, sizeof(res));
return ret;
}
#endif
#ifdef HEIM_WEAK_CRYPTO
static krb5_error_code
CRC32_checksum(krb5_context context,
struct key_data *key,
const void *data,
size_t len,
unsigned usage,
Checksum *C)
{
uint32_t crc;
unsigned char *r = C->checksum.data;
_krb5_crc_init_table ();
crc = _krb5_crc_update (data, len, 0);
r[0] = crc & 0xff;
r[1] = (crc >> 8) & 0xff;
r[2] = (crc >> 16) & 0xff;
r[3] = (crc >> 24) & 0xff;
return 0;
}
static krb5_error_code
RSA_MD4_checksum(krb5_context context,
struct key_data *key,
const void *data,
size_t len,
unsigned usage,
Checksum *C)
{
if (EVP_Digest(data, len, C->checksum.data, NULL, EVP_md4(), NULL) != 1)
krb5_abortx(context, "md4 checksum failed");
return 0;
}
static krb5_error_code
RSA_MD4_DES_checksum(krb5_context context,
struct key_data *key,
const void *data,
size_t len,
unsigned usage,
Checksum *cksum)
{
return des_checksum(context, EVP_md4(), key, data, len, cksum);
}
static krb5_error_code
RSA_MD4_DES_verify(krb5_context context,
struct key_data *key,
const void *data,
size_t len,
unsigned usage,
Checksum *C)
{
return des_verify(context, EVP_md5(), key, data, len, C);
}
static krb5_error_code
RSA_MD5_DES_checksum(krb5_context context,
struct key_data *key,
const void *data,
size_t len,
unsigned usage,
Checksum *C)
{
return des_checksum(context, EVP_md5(), key, data, len, C);
}
static krb5_error_code
RSA_MD5_DES_verify(krb5_context context,
struct key_data *key,
const void *data,
size_t len,
unsigned usage,
Checksum *C)
{
return des_verify(context, EVP_md5(), key, data, len, C);
}
#endif /* HEIM_WEAK_CRYPTO */
#ifdef DES3_OLD_ENCTYPE
static krb5_error_code
RSA_MD5_DES3_checksum(krb5_context context,
struct key_data *key,
const void *data,
size_t len,
unsigned usage,
Checksum *C)
{
return des_checksum(context, EVP_md5(), key, data, len, C);
}
static krb5_error_code
RSA_MD5_DES3_verify(krb5_context context,
struct key_data *key,
const void *data,
size_t len,
unsigned usage,
Checksum *C)
{
return des_verify(context, EVP_md5(), key, data, len, C);
}
#endif
static krb5_error_code
SHA1_checksum(krb5_context context,
struct key_data *key,
const void *data,
size_t len,
unsigned usage,
Checksum *C)
{
if (EVP_Digest(data, len, C->checksum.data, NULL, EVP_sha1(), NULL) != 1)
krb5_abortx(context, "sha1 checksum failed");
return 0;
}
/* HMAC according to RFC2104 */
static krb5_error_code
hmac(krb5_context context,
struct checksum_type *cm,
const void *data,
size_t len,
unsigned usage,
struct key_data *keyblock,
Checksum *result)
{
unsigned char *ipad, *opad;
unsigned char *key;
size_t key_len;
int i;
ipad = malloc(cm->blocksize + len);
if (ipad == NULL)
return ENOMEM;
opad = malloc(cm->blocksize + cm->checksumsize);
if (opad == NULL) {
free(ipad);
return ENOMEM;
}
memset(ipad, 0x36, cm->blocksize);
memset(opad, 0x5c, cm->blocksize);
if(keyblock->key->keyvalue.length > cm->blocksize){
(*cm->checksum)(context,
keyblock,
keyblock->key->keyvalue.data,
keyblock->key->keyvalue.length,
usage,
result);
key = result->checksum.data;
key_len = result->checksum.length;
} else {
key = keyblock->key->keyvalue.data;
key_len = keyblock->key->keyvalue.length;
}
for(i = 0; i < key_len; i++){
ipad[i] ^= key[i];
opad[i] ^= key[i];
}
memcpy(ipad + cm->blocksize, data, len);
(*cm->checksum)(context, keyblock, ipad, cm->blocksize + len,
usage, result);
memcpy(opad + cm->blocksize, result->checksum.data,
result->checksum.length);
(*cm->checksum)(context, keyblock, opad,
cm->blocksize + cm->checksumsize, usage, result);
memset(ipad, 0, cm->blocksize + len);
free(ipad);
memset(opad, 0, cm->blocksize + cm->checksumsize);
free(opad);
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_hmac(krb5_context context,
krb5_cksumtype cktype,
const void *data,
size_t len,
unsigned usage,
krb5_keyblock *key,
Checksum *result)
{
struct checksum_type *c = _find_checksum(cktype);
struct key_data kd;
krb5_error_code ret;
if (c == NULL) {
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("checksum type %d not supported", ""),
cktype);
return KRB5_PROG_SUMTYPE_NOSUPP;
}
kd.key = key;
kd.schedule = NULL;
ret = hmac(context, c, data, len, usage, &kd, result);
if (kd.schedule)
krb5_free_data(context, kd.schedule);
return ret;
}
static krb5_error_code
SP_HMAC_SHA1_checksum(krb5_context context,
struct key_data *key,
const void *data,
size_t len,
unsigned usage,
Checksum *result)
{
struct checksum_type *c = _find_checksum(CKSUMTYPE_SHA1);
Checksum res;
char sha1_data[20];
krb5_error_code ret;
res.checksum.data = sha1_data;
res.checksum.length = sizeof(sha1_data);
ret = hmac(context, c, data, len, usage, key, &res);
if (ret)
krb5_abortx(context, "hmac failed");
memcpy(result->checksum.data, res.checksum.data, result->checksum.length);
return 0;
}
/*
* checksum according to section 5. of draft-brezak-win2k-krb-rc4-hmac-03.txt
*/
static krb5_error_code
HMAC_MD5_checksum(krb5_context context,
struct key_data *key,
const void *data,
size_t len,
unsigned usage,
Checksum *result)
{
EVP_MD_CTX *m;
struct checksum_type *c = _find_checksum (CKSUMTYPE_RSA_MD5);
const char signature[] = "signaturekey";
Checksum ksign_c;
struct key_data ksign;
krb5_keyblock kb;
unsigned char t[4];
unsigned char tmp[16];
unsigned char ksign_c_data[16];
krb5_error_code ret;
m = EVP_MD_CTX_create();
if (m == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
ksign_c.checksum.length = sizeof(ksign_c_data);
ksign_c.checksum.data = ksign_c_data;
ret = hmac(context, c, signature, sizeof(signature), 0, key, &ksign_c);
if (ret) {
EVP_MD_CTX_destroy(m);
return ret;
}
ksign.key = &kb;
kb.keyvalue = ksign_c.checksum;
EVP_DigestInit_ex(m, EVP_md5(), NULL);
t[0] = (usage >> 0) & 0xFF;
t[1] = (usage >> 8) & 0xFF;
t[2] = (usage >> 16) & 0xFF;
t[3] = (usage >> 24) & 0xFF;
EVP_DigestUpdate(m, t, 4);
EVP_DigestUpdate(m, data, len);
EVP_DigestFinal_ex (m, tmp, NULL);
EVP_MD_CTX_destroy(m);
ret = hmac(context, c, tmp, sizeof(tmp), 0, &ksign, result);
if (ret)
return ret;
return 0;
}
static struct checksum_type checksum_none = {
CKSUMTYPE_NONE,
"none",
1,
0,
0,
NONE_checksum,
NULL
};
#ifdef HEIM_WEAK_CRYPTO
static struct checksum_type checksum_crc32 = {
CKSUMTYPE_CRC32,
"crc32",
1,
4,
0,
CRC32_checksum,
NULL
};
static struct checksum_type checksum_rsa_md4 = {
CKSUMTYPE_RSA_MD4,
"rsa-md4",
64,
16,
F_CPROOF,
RSA_MD4_checksum,
NULL
};
static struct checksum_type checksum_rsa_md4_des = {
CKSUMTYPE_RSA_MD4_DES,
"rsa-md4-des",
64,
24,
F_KEYED | F_CPROOF | F_VARIANT,
RSA_MD4_DES_checksum,
RSA_MD4_DES_verify
};
static struct checksum_type checksum_rsa_md5_des = {
CKSUMTYPE_RSA_MD5_DES,
"rsa-md5-des",
64,
24,
F_KEYED | F_CPROOF | F_VARIANT,
RSA_MD5_DES_checksum,
RSA_MD5_DES_verify
};
#endif /* HEIM_WEAK_CRYPTO */
static krb5_error_code
RSA_MD5_checksum(krb5_context context,
struct key_data *key,
const void *data,
size_t len,
unsigned usage,
Checksum *C)
{
if (EVP_Digest(data, len, C->checksum.data, NULL, EVP_md5(), NULL) != 1)
krb5_abortx(context, "md5 checksum failed");
return 0;
}
static struct checksum_type checksum_rsa_md5 = {
CKSUMTYPE_RSA_MD5,
"rsa-md5",
64,
16,
F_CPROOF,
RSA_MD5_checksum,
NULL
};
#ifdef DES3_OLD_ENCTYPE
static struct checksum_type checksum_rsa_md5_des3 = {
CKSUMTYPE_RSA_MD5_DES3,
"rsa-md5-des3",
64,
24,
F_KEYED | F_CPROOF | F_VARIANT,
RSA_MD5_DES3_checksum,
RSA_MD5_DES3_verify
};
#endif
static struct checksum_type checksum_sha1 = {
CKSUMTYPE_SHA1,
"sha1",
64,
20,
F_CPROOF,
SHA1_checksum,
NULL
};
static struct checksum_type checksum_hmac_sha1_des3 = {
CKSUMTYPE_HMAC_SHA1_DES3,
"hmac-sha1-des3",
64,
20,
F_KEYED | F_CPROOF | F_DERIVED,
SP_HMAC_SHA1_checksum,
NULL
};
static struct checksum_type checksum_hmac_sha1_aes128 = {
CKSUMTYPE_HMAC_SHA1_96_AES_128,
"hmac-sha1-96-aes128",
64,
12,
F_KEYED | F_CPROOF | F_DERIVED,
SP_HMAC_SHA1_checksum,
NULL
};
static struct checksum_type checksum_hmac_sha1_aes256 = {
CKSUMTYPE_HMAC_SHA1_96_AES_256,
"hmac-sha1-96-aes256",
64,
12,
F_KEYED | F_CPROOF | F_DERIVED,
SP_HMAC_SHA1_checksum,
NULL
};
static struct checksum_type checksum_hmac_md5 = {
CKSUMTYPE_HMAC_MD5,
"hmac-md5",
64,
16,
F_KEYED | F_CPROOF,
HMAC_MD5_checksum,
NULL
};
static struct checksum_type *checksum_types[] = {
&checksum_none,
#ifdef HEIM_WEAK_CRYPTO
&checksum_crc32,
&checksum_rsa_md4,
&checksum_rsa_md4_des,
&checksum_rsa_md5_des,
#endif
#ifdef DES3_OLD_ENCTYPE
&checksum_rsa_md5_des3,
#endif
&checksum_rsa_md5,
&checksum_sha1,
&checksum_hmac_sha1_des3,
&checksum_hmac_sha1_aes128,
&checksum_hmac_sha1_aes256,
&checksum_hmac_md5
};
static int num_checksums = sizeof(checksum_types) / sizeof(checksum_types[0]);
static struct checksum_type *
_find_checksum(krb5_cksumtype type)
{
int i;
for(i = 0; i < num_checksums; i++)
if(checksum_types[i]->type == type)
return checksum_types[i];
return NULL;
}
static krb5_error_code
get_checksum_key(krb5_context context,
krb5_crypto crypto,
unsigned usage, /* not krb5_key_usage */
struct checksum_type *ct,
struct key_data **key)
{
krb5_error_code ret = 0;
if(ct->flags & F_DERIVED)
ret = _get_derived_key(context, crypto, usage, key);
else if(ct->flags & F_VARIANT) {
int i;
*key = _new_derived_key(crypto, 0xff/* KRB5_KU_RFC1510_VARIANT */);
if(*key == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
ret = krb5_copy_keyblock(context, crypto->key.key, &(*key)->key);
if(ret)
return ret;
for(i = 0; i < (*key)->key->keyvalue.length; i++)
((unsigned char*)(*key)->key->keyvalue.data)[i] ^= 0xF0;
} else {
*key = &crypto->key;
}
if(ret == 0)
ret = _key_schedule(context, *key);
return ret;
}
static krb5_error_code
create_checksum (krb5_context context,
struct checksum_type *ct,
krb5_crypto crypto,
unsigned usage,
void *data,
size_t len,
Checksum *result)
{
krb5_error_code ret;
struct key_data *dkey;
int keyed_checksum;
if (ct->flags & F_DISABLED) {
krb5_clear_error_message (context);
return KRB5_PROG_SUMTYPE_NOSUPP;
}
keyed_checksum = (ct->flags & F_KEYED) != 0;
if(keyed_checksum && crypto == NULL) {
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("Checksum type %s is keyed but no "
"crypto context (key) was passed in", ""),
ct->name);
return KRB5_PROG_SUMTYPE_NOSUPP; /* XXX */
}
if(keyed_checksum) {
ret = get_checksum_key(context, crypto, usage, ct, &dkey);
if (ret)
return ret;
} else
dkey = NULL;
result->cksumtype = ct->type;
ret = krb5_data_alloc(&result->checksum, ct->checksumsize);
if (ret)
return (ret);
return (*ct->checksum)(context, dkey, data, len, usage, result);
}
static int
arcfour_checksum_p(struct checksum_type *ct, krb5_crypto crypto)
{
return (ct->type == CKSUMTYPE_HMAC_MD5) &&
(crypto->key.key->keytype == KEYTYPE_ARCFOUR);
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_create_checksum(krb5_context context,
krb5_crypto crypto,
krb5_key_usage usage,
int type,
void *data,
size_t len,
Checksum *result)
{
struct checksum_type *ct = NULL;
unsigned keyusage;
/* type 0 -> pick from crypto */
if (type) {
ct = _find_checksum(type);
} else if (crypto) {
ct = crypto->et->keyed_checksum;
if (ct == NULL)
ct = crypto->et->checksum;
}
if(ct == NULL) {
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("checksum type %d not supported", ""),
type);
return KRB5_PROG_SUMTYPE_NOSUPP;
}
if (arcfour_checksum_p(ct, crypto)) {
keyusage = usage;
usage2arcfour(context, &keyusage);
} else
keyusage = CHECKSUM_USAGE(usage);
return create_checksum(context, ct, crypto, keyusage,
data, len, result);
}
static krb5_error_code
verify_checksum(krb5_context context,
krb5_crypto crypto,
unsigned usage, /* not krb5_key_usage */
void *data,
size_t len,
Checksum *cksum)
{
krb5_error_code ret;
struct key_data *dkey;
int keyed_checksum;
Checksum c;
struct checksum_type *ct;
ct = _find_checksum(cksum->cksumtype);
if (ct == NULL || (ct->flags & F_DISABLED)) {
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("checksum type %d not supported", ""),
cksum->cksumtype);
return KRB5_PROG_SUMTYPE_NOSUPP;
}
if(ct->checksumsize != cksum->checksum.length) {
krb5_clear_error_message (context);
return KRB5KRB_AP_ERR_BAD_INTEGRITY; /* XXX */
}
keyed_checksum = (ct->flags & F_KEYED) != 0;
if(keyed_checksum) {
struct checksum_type *kct;
if (crypto == NULL) {
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("Checksum type %s is keyed but no "
"crypto context (key) was passed in", ""),
ct->name);
return KRB5_PROG_SUMTYPE_NOSUPP; /* XXX */
}
kct = crypto->et->keyed_checksum;
if (kct != NULL && kct->type != ct->type) {
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("Checksum type %s is keyed, but "
"the key type %s passed didnt have that checksum "
"type as the keyed type", ""),
ct->name, crypto->et->name);
return KRB5_PROG_SUMTYPE_NOSUPP; /* XXX */
}
ret = get_checksum_key(context, crypto, usage, ct, &dkey);
if (ret)
return ret;
} else
dkey = NULL;
if(ct->verify)
return (*ct->verify)(context, dkey, data, len, usage, cksum);
ret = krb5_data_alloc (&c.checksum, ct->checksumsize);
if (ret)
return ret;
ret = (*ct->checksum)(context, dkey, data, len, usage, &c);
if (ret) {
krb5_data_free(&c.checksum);
return ret;
}
if(c.checksum.length != cksum->checksum.length ||
ct_memcmp(c.checksum.data, cksum->checksum.data, c.checksum.length)) {
krb5_clear_error_message (context);
ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
} else {
ret = 0;
}
krb5_data_free (&c.checksum);
return ret;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_verify_checksum(krb5_context context,
krb5_crypto crypto,
krb5_key_usage usage,
void *data,
size_t len,
Checksum *cksum)
{
struct checksum_type *ct;
unsigned keyusage;
ct = _find_checksum(cksum->cksumtype);
if(ct == NULL) {
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("checksum type %d not supported", ""),
cksum->cksumtype);
return KRB5_PROG_SUMTYPE_NOSUPP;
}
if (arcfour_checksum_p(ct, crypto)) {
keyusage = usage;
usage2arcfour(context, &keyusage);
} else
keyusage = CHECKSUM_USAGE(usage);
return verify_checksum(context, crypto, keyusage,
data, len, cksum);
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_crypto_get_checksum_type(krb5_context context,
krb5_crypto crypto,
krb5_cksumtype *type)
{
struct checksum_type *ct = NULL;
if (crypto != NULL) {
ct = crypto->et->keyed_checksum;
if (ct == NULL)
ct = crypto->et->checksum;
}
if (ct == NULL) {
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("checksum type not found", ""));
return KRB5_PROG_SUMTYPE_NOSUPP;
}
*type = ct->type;
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_checksumsize(krb5_context context,
krb5_cksumtype type,
size_t *size)
{
struct checksum_type *ct = _find_checksum(type);
if(ct == NULL) {
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("checksum type %d not supported", ""),
type);
return KRB5_PROG_SUMTYPE_NOSUPP;
}
*size = ct->checksumsize;
return 0;
}
KRB5_LIB_FUNCTION krb5_boolean KRB5_LIB_CALL
krb5_checksum_is_keyed(krb5_context context,
krb5_cksumtype type)
{
struct checksum_type *ct = _find_checksum(type);
if(ct == NULL) {
if (context)
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("checksum type %d not supported", ""),
type);
return KRB5_PROG_SUMTYPE_NOSUPP;
}
return ct->flags & F_KEYED;
}
KRB5_LIB_FUNCTION krb5_boolean KRB5_LIB_CALL
krb5_checksum_is_collision_proof(krb5_context context,
krb5_cksumtype type)
{
struct checksum_type *ct = _find_checksum(type);
if(ct == NULL) {
if (context)
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("checksum type %d not supported", ""),
type);
return KRB5_PROG_SUMTYPE_NOSUPP;
}
return ct->flags & F_CPROOF;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_checksum_disable(krb5_context context,
krb5_cksumtype type)
{
struct checksum_type *ct = _find_checksum(type);
if(ct == NULL) {
if (context)
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("checksum type %d not supported", ""),
type);
return KRB5_PROG_SUMTYPE_NOSUPP;
}
ct->flags |= F_DISABLED;
return 0;
}
/************************************************************
* *
************************************************************/
static krb5_error_code
NULL_encrypt(krb5_context context,
struct key_data *key,
void *data,
size_t len,
krb5_boolean encryptp,
int usage,
void *ivec)
{
return 0;
}
static krb5_error_code
evp_encrypt(krb5_context context,
struct key_data *key,
void *data,
size_t len,
krb5_boolean encryptp,
int usage,
void *ivec)
{
struct evp_schedule *ctx = key->schedule->data;
EVP_CIPHER_CTX *c;
c = encryptp ? &ctx->ectx : &ctx->dctx;
if (ivec == NULL) {
/* alloca ? */
size_t len = EVP_CIPHER_CTX_iv_length(c);
void *loiv = malloc(len);
if (loiv == NULL) {
krb5_clear_error_message(context);
return ENOMEM;
}
memset(loiv, 0, len);
EVP_CipherInit_ex(c, NULL, NULL, NULL, loiv, -1);
free(loiv);
} else
EVP_CipherInit_ex(c, NULL, NULL, NULL, ivec, -1);
EVP_Cipher(c, data, data, len);
return 0;
}
static const unsigned char zero_ivec[EVP_MAX_BLOCK_LENGTH] = { 0 };
static krb5_error_code
evp_encrypt_cts(krb5_context context,
struct key_data *key,
void *data,
size_t len,
krb5_boolean encryptp,
int usage,
void *ivec)
{
size_t i, blocksize;
struct evp_schedule *ctx = key->schedule->data;
char tmp[EVP_MAX_BLOCK_LENGTH], ivec2[EVP_MAX_BLOCK_LENGTH];
EVP_CIPHER_CTX *c;
unsigned char *p;
c = encryptp ? &ctx->ectx : &ctx->dctx;
blocksize = EVP_CIPHER_CTX_block_size(c);
if (len < blocksize) {
krb5_set_error_message(context, EINVAL,
"message block too short");
return EINVAL;
} else if (len == blocksize) {
EVP_CipherInit_ex(c, NULL, NULL, NULL, zero_ivec, -1);
EVP_Cipher(c, data, data, len);
return 0;
}
if (ivec)
EVP_CipherInit_ex(c, NULL, NULL, NULL, ivec, -1);
else
EVP_CipherInit_ex(c, NULL, NULL, NULL, zero_ivec, -1);
if (encryptp) {
p = data;
i = ((len - 1) / blocksize) * blocksize;
EVP_Cipher(c, p, p, i);
p += i - blocksize;
len -= i;
memcpy(ivec2, p, blocksize);
for (i = 0; i < len; i++)
tmp[i] = p[i + blocksize] ^ ivec2[i];
for (; i < blocksize; i++)
tmp[i] = 0 ^ ivec2[i];
EVP_CipherInit_ex(c, NULL, NULL, NULL, zero_ivec, -1);
EVP_Cipher(c, p, tmp, blocksize);
memcpy(p + blocksize, ivec2, len);
if (ivec)
memcpy(ivec, p, blocksize);
} else {
char tmp2[EVP_MAX_BLOCK_LENGTH], tmp3[EVP_MAX_BLOCK_LENGTH];
p = data;
if (len > blocksize * 2) {
/* remove last two blocks and round up, decrypt this with cbc, then do cts dance */
i = ((((len - blocksize * 2) + blocksize - 1) / blocksize) * blocksize);
memcpy(ivec2, p + i - blocksize, blocksize);
EVP_Cipher(c, p, p, i);
p += i;
len -= i + blocksize;
} else {
if (ivec)
memcpy(ivec2, ivec, blocksize);
else
memcpy(ivec2, zero_ivec, blocksize);
len -= blocksize;
}
memcpy(tmp, p, blocksize);
EVP_CipherInit_ex(c, NULL, NULL, NULL, zero_ivec, -1);
EVP_Cipher(c, tmp2, p, blocksize);
memcpy(tmp3, p + blocksize, len);
memcpy(tmp3 + len, tmp2 + len, blocksize - len); /* xor 0 */
for (i = 0; i < len; i++)
p[i + blocksize] = tmp2[i] ^ tmp3[i];
EVP_CipherInit_ex(c, NULL, NULL, NULL, zero_ivec, -1);
EVP_Cipher(c, p, tmp3, blocksize);
for (i = 0; i < blocksize; i++)
p[i] ^= ivec2[i];
if (ivec)
memcpy(ivec, tmp, blocksize);
}
return 0;
}
#ifdef HEIM_WEAK_CRYPTO
static krb5_error_code
evp_des_encrypt_null_ivec(krb5_context context,
struct key_data *key,
void *data,
size_t len,
krb5_boolean encryptp,
int usage,
void *ignore_ivec)
{
struct evp_schedule *ctx = key->schedule->data;
EVP_CIPHER_CTX *c;
DES_cblock ivec;
memset(&ivec, 0, sizeof(ivec));
c = encryptp ? &ctx->ectx : &ctx->dctx;
EVP_CipherInit_ex(c, NULL, NULL, NULL, (void *)&ivec, -1);
EVP_Cipher(c, data, data, len);
return 0;
}
static krb5_error_code
evp_des_encrypt_key_ivec(krb5_context context,
struct key_data *key,
void *data,
size_t len,
krb5_boolean encryptp,
int usage,
void *ignore_ivec)
{
struct evp_schedule *ctx = key->schedule->data;
EVP_CIPHER_CTX *c;
DES_cblock ivec;
memcpy(&ivec, key->key->keyvalue.data, sizeof(ivec));
c = encryptp ? &ctx->ectx : &ctx->dctx;
EVP_CipherInit_ex(c, NULL, NULL, NULL, (void *)&ivec, -1);
EVP_Cipher(c, data, data, len);
return 0;
}
static krb5_error_code
DES_CFB64_encrypt_null_ivec(krb5_context context,
struct key_data *key,
void *data,
size_t len,
krb5_boolean encryptp,
int usage,
void *ignore_ivec)
{
DES_cblock ivec;
int num = 0;
DES_key_schedule *s = key->schedule->data;
memset(&ivec, 0, sizeof(ivec));
DES_cfb64_encrypt(data, data, len, s, &ivec, &num, encryptp);
return 0;
}
static krb5_error_code
DES_PCBC_encrypt_key_ivec(krb5_context context,
struct key_data *key,
void *data,
size_t len,
krb5_boolean encryptp,
int usage,
void *ignore_ivec)
{
DES_cblock ivec;
DES_key_schedule *s = key->schedule->data;
memcpy(&ivec, key->key->keyvalue.data, sizeof(ivec));
DES_pcbc_encrypt(data, data, len, s, &ivec, encryptp);
return 0;
}
#endif
/*
* section 6 of draft-brezak-win2k-krb-rc4-hmac-03
*
* warning: not for small children
*/
static krb5_error_code
ARCFOUR_subencrypt(krb5_context context,
struct key_data *key,
void *data,
size_t len,
unsigned usage,
void *ivec)
{
EVP_CIPHER_CTX ctx;
struct checksum_type *c = _find_checksum (CKSUMTYPE_RSA_MD5);
Checksum k1_c, k2_c, k3_c, cksum;
struct key_data ke;
krb5_keyblock kb;
unsigned char t[4];
unsigned char *cdata = data;
unsigned char k1_c_data[16], k2_c_data[16], k3_c_data[16];
krb5_error_code ret;
t[0] = (usage >> 0) & 0xFF;
t[1] = (usage >> 8) & 0xFF;
t[2] = (usage >> 16) & 0xFF;
t[3] = (usage >> 24) & 0xFF;
k1_c.checksum.length = sizeof(k1_c_data);
k1_c.checksum.data = k1_c_data;
ret = hmac(NULL, c, t, sizeof(t), 0, key, &k1_c);
if (ret)
krb5_abortx(context, "hmac failed");
memcpy (k2_c_data, k1_c_data, sizeof(k1_c_data));
k2_c.checksum.length = sizeof(k2_c_data);
k2_c.checksum.data = k2_c_data;
ke.key = &kb;
kb.keyvalue = k2_c.checksum;
cksum.checksum.length = 16;
cksum.checksum.data = data;
ret = hmac(NULL, c, cdata + 16, len - 16, 0, &ke, &cksum);
if (ret)
krb5_abortx(context, "hmac failed");
ke.key = &kb;
kb.keyvalue = k1_c.checksum;
k3_c.checksum.length = sizeof(k3_c_data);
k3_c.checksum.data = k3_c_data;
ret = hmac(NULL, c, data, 16, 0, &ke, &k3_c);
if (ret)
krb5_abortx(context, "hmac failed");
EVP_CIPHER_CTX_init(&ctx);
EVP_CipherInit_ex(&ctx, EVP_rc4(), NULL, k3_c.checksum.data, NULL, 1);
EVP_Cipher(&ctx, cdata + 16, cdata + 16, len - 16);
EVP_CIPHER_CTX_cleanup(&ctx);
memset (k1_c_data, 0, sizeof(k1_c_data));
memset (k2_c_data, 0, sizeof(k2_c_data));
memset (k3_c_data, 0, sizeof(k3_c_data));
return 0;
}
static krb5_error_code
ARCFOUR_subdecrypt(krb5_context context,
struct key_data *key,
void *data,
size_t len,
unsigned usage,
void *ivec)
{
EVP_CIPHER_CTX ctx;
struct checksum_type *c = _find_checksum (CKSUMTYPE_RSA_MD5);
Checksum k1_c, k2_c, k3_c, cksum;
struct key_data ke;
krb5_keyblock kb;
unsigned char t[4];
unsigned char *cdata = data;
unsigned char k1_c_data[16], k2_c_data[16], k3_c_data[16];
unsigned char cksum_data[16];
krb5_error_code ret;
t[0] = (usage >> 0) & 0xFF;
t[1] = (usage >> 8) & 0xFF;
t[2] = (usage >> 16) & 0xFF;
t[3] = (usage >> 24) & 0xFF;
k1_c.checksum.length = sizeof(k1_c_data);
k1_c.checksum.data = k1_c_data;
ret = hmac(NULL, c, t, sizeof(t), 0, key, &k1_c);
if (ret)
krb5_abortx(context, "hmac failed");
memcpy (k2_c_data, k1_c_data, sizeof(k1_c_data));
k2_c.checksum.length = sizeof(k2_c_data);
k2_c.checksum.data = k2_c_data;
ke.key = &kb;
kb.keyvalue = k1_c.checksum;
k3_c.checksum.length = sizeof(k3_c_data);
k3_c.checksum.data = k3_c_data;
ret = hmac(NULL, c, cdata, 16, 0, &ke, &k3_c);
if (ret)
krb5_abortx(context, "hmac failed");
EVP_CIPHER_CTX_init(&ctx);
EVP_CipherInit_ex(&ctx, EVP_rc4(), NULL, k3_c.checksum.data, NULL, 0);
EVP_Cipher(&ctx, cdata + 16, cdata + 16, len - 16);
EVP_CIPHER_CTX_cleanup(&ctx);
ke.key = &kb;
kb.keyvalue = k2_c.checksum;
cksum.checksum.length = 16;
cksum.checksum.data = cksum_data;
ret = hmac(NULL, c, cdata + 16, len - 16, 0, &ke, &cksum);
if (ret)
krb5_abortx(context, "hmac failed");
memset (k1_c_data, 0, sizeof(k1_c_data));
memset (k2_c_data, 0, sizeof(k2_c_data));
memset (k3_c_data, 0, sizeof(k3_c_data));
if (ct_memcmp (cksum.checksum.data, data, 16) != 0) {
krb5_clear_error_message (context);
return KRB5KRB_AP_ERR_BAD_INTEGRITY;
} else {
return 0;
}
}
/*
* convert the usage numbers used in
* draft-ietf-cat-kerb-key-derivation-00.txt to the ones in
* draft-brezak-win2k-krb-rc4-hmac-04.txt
*/
static krb5_error_code
usage2arcfour (krb5_context context, unsigned *usage)
{
switch (*usage) {
case KRB5_KU_AS_REP_ENC_PART : /* 3 */
*usage = 8;
return 0;
case KRB5_KU_USAGE_SEAL : /* 22 */
*usage = 13;
return 0;
case KRB5_KU_USAGE_SIGN : /* 23 */
*usage = 15;
return 0;
case KRB5_KU_USAGE_SEQ: /* 24 */
*usage = 0;
return 0;
default :
return 0;
}
}
static krb5_error_code
ARCFOUR_encrypt(krb5_context context,
struct key_data *key,
void *data,
size_t len,
krb5_boolean encryptp,
int usage,
void *ivec)
{
krb5_error_code ret;
unsigned keyusage = usage;
if((ret = usage2arcfour (context, &keyusage)) != 0)
return ret;
if (encryptp)
return ARCFOUR_subencrypt (context, key, data, len, keyusage, ivec);
else
return ARCFOUR_subdecrypt (context, key, data, len, keyusage, ivec);
}
/*
*
*/
static krb5_error_code
AES_PRF(krb5_context context,
krb5_crypto crypto,
const krb5_data *in,
krb5_data *out)
{
struct checksum_type *ct = crypto->et->checksum;
krb5_error_code ret;
Checksum result;
krb5_keyblock *derived;
result.cksumtype = ct->type;
ret = krb5_data_alloc(&result.checksum, ct->checksumsize);
if (ret) {
krb5_set_error_message(context, ret, N_("malloc: out memory", ""));
return ret;
}
ret = (*ct->checksum)(context, NULL, in->data, in->length, 0, &result);
if (ret) {
krb5_data_free(&result.checksum);
return ret;
}
if (result.checksum.length < crypto->et->blocksize)
krb5_abortx(context, "internal prf error");
derived = NULL;
ret = krb5_derive_key(context, crypto->key.key,
crypto->et->type, "prf", 3, &derived);
if (ret)
krb5_abortx(context, "krb5_derive_key");
ret = krb5_data_alloc(out, crypto->et->blocksize);
if (ret)
krb5_abortx(context, "malloc failed");
{
const EVP_CIPHER *c = (*crypto->et->keytype->evp)();
EVP_CIPHER_CTX ctx;
EVP_CIPHER_CTX_init(&ctx); /* ivec all zero */
EVP_CipherInit_ex(&ctx, c, NULL, derived->keyvalue.data, NULL, 1);
EVP_Cipher(&ctx, out->data, result.checksum.data,
crypto->et->blocksize);
EVP_CIPHER_CTX_cleanup(&ctx);
}
krb5_data_free(&result.checksum);
krb5_free_keyblock(context, derived);
return ret;
}
/*
* these should currently be in reverse preference order.
* (only relevant for !F_PSEUDO) */
static struct encryption_type enctype_null = {
ETYPE_NULL,
"null",
1,
1,
0,
&keytype_null,
&checksum_none,
NULL,
F_DISABLED,
NULL_encrypt,
0,
NULL
};
static struct encryption_type enctype_arcfour_hmac_md5 = {
ETYPE_ARCFOUR_HMAC_MD5,
"arcfour-hmac-md5",
1,
1,
8,
&keytype_arcfour,
&checksum_hmac_md5,
NULL,
F_SPECIAL,
ARCFOUR_encrypt,
0,
NULL
};
#ifdef DES3_OLD_ENCTYPE
static struct encryption_type enctype_des3_cbc_md5 = {
ETYPE_DES3_CBC_MD5,
"des3-cbc-md5",
8,
8,
8,
&keytype_des3,
&checksum_rsa_md5,
&checksum_rsa_md5_des3,
0,
evp_encrypt,
0,
NULL
};
#endif
static struct encryption_type enctype_des3_cbc_sha1 = {
ETYPE_DES3_CBC_SHA1,
"des3-cbc-sha1",
8,
8,
8,
&keytype_des3_derived,
&checksum_sha1,
&checksum_hmac_sha1_des3,
F_DERIVED,
evp_encrypt,
0,
NULL
};
#ifdef DES3_OLD_ENCTYPE
static struct encryption_type enctype_old_des3_cbc_sha1 = {
ETYPE_OLD_DES3_CBC_SHA1,
"old-des3-cbc-sha1",
8,
8,
8,
&keytype_des3,
&checksum_sha1,
&checksum_hmac_sha1_des3,
0,
evp_encrypt,
0,
NULL
};
#endif
static struct encryption_type enctype_aes128_cts_hmac_sha1 = {
ETYPE_AES128_CTS_HMAC_SHA1_96,
"aes128-cts-hmac-sha1-96",
16,
1,
16,
&keytype_aes128,
&checksum_sha1,
&checksum_hmac_sha1_aes128,
F_DERIVED,
evp_encrypt_cts,
16,
AES_PRF
};
static struct encryption_type enctype_aes256_cts_hmac_sha1 = {
ETYPE_AES256_CTS_HMAC_SHA1_96,
"aes256-cts-hmac-sha1-96",
16,
1,
16,
&keytype_aes256,
&checksum_sha1,
&checksum_hmac_sha1_aes256,
F_DERIVED,
evp_encrypt_cts,
16,
AES_PRF
};
static struct encryption_type enctype_des3_cbc_none = {
ETYPE_DES3_CBC_NONE,
"des3-cbc-none",
8,
8,
0,
&keytype_des3_derived,
&checksum_none,
NULL,
F_PSEUDO,
evp_encrypt,
0,
NULL
};
#ifdef HEIM_WEAK_CRYPTO
static struct encryption_type enctype_des_cbc_crc = {
ETYPE_DES_CBC_CRC,
"des-cbc-crc",
8,
8,
8,
&keytype_des,
&checksum_crc32,
NULL,
F_DISABLED,
evp_des_encrypt_key_ivec,
0,
NULL
};
static struct encryption_type enctype_des_cbc_md4 = {
ETYPE_DES_CBC_MD4,
"des-cbc-md4",
8,
8,
8,
&keytype_des,
&checksum_rsa_md4,
&checksum_rsa_md4_des,
F_DISABLED,
evp_des_encrypt_null_ivec,
0,
NULL
};
static struct encryption_type enctype_des_cbc_md5 = {
ETYPE_DES_CBC_MD5,
"des-cbc-md5",
8,
8,
8,
&keytype_des,
&checksum_rsa_md5,
&checksum_rsa_md5_des,
F_DISABLED,
evp_des_encrypt_null_ivec,
0,
NULL
};
static struct encryption_type enctype_des_cbc_none = {
ETYPE_DES_CBC_NONE,
"des-cbc-none",
8,
8,
0,
&keytype_des,
&checksum_none,
NULL,
F_PSEUDO|F_DISABLED,
evp_des_encrypt_null_ivec,
0,
NULL
};
static struct encryption_type enctype_des_cfb64_none = {
ETYPE_DES_CFB64_NONE,
"des-cfb64-none",
1,
1,
0,
&keytype_des_old,
&checksum_none,
NULL,
F_PSEUDO|F_DISABLED,
DES_CFB64_encrypt_null_ivec,
0,
NULL
};
static struct encryption_type enctype_des_pcbc_none = {
ETYPE_DES_PCBC_NONE,
"des-pcbc-none",
8,
8,
0,
&keytype_des_old,
&checksum_none,
NULL,
F_PSEUDO|F_DISABLED,
DES_PCBC_encrypt_key_ivec,
0,
NULL
};
#endif /* HEIM_WEAK_CRYPTO */
static struct encryption_type *etypes[] = {
&enctype_aes256_cts_hmac_sha1,
&enctype_aes128_cts_hmac_sha1,
&enctype_des3_cbc_sha1,
&enctype_des3_cbc_none, /* used by the gss-api mech */
&enctype_arcfour_hmac_md5,
#ifdef DES3_OLD_ENCTYPE
&enctype_des3_cbc_md5,
&enctype_old_des3_cbc_sha1,
#endif
#ifdef HEIM_WEAK_CRYPTO
&enctype_des_cbc_crc,
&enctype_des_cbc_md4,
&enctype_des_cbc_md5,
&enctype_des_cbc_none,
&enctype_des_cfb64_none,
&enctype_des_pcbc_none,
#endif
&enctype_null
};
static unsigned num_etypes = sizeof(etypes) / sizeof(etypes[0]);
static struct encryption_type *
_find_enctype(krb5_enctype type)
{
int i;
for(i = 0; i < num_etypes; i++)
if(etypes[i]->type == type)
return etypes[i];
return NULL;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_enctype_to_string(krb5_context context,
krb5_enctype etype,
char **string)
{
struct encryption_type *e;
e = _find_enctype(etype);
if(e == NULL) {
krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
etype);
*string = NULL;
return KRB5_PROG_ETYPE_NOSUPP;
}
*string = strdup(e->name);
if(*string == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_string_to_enctype(krb5_context context,
const char *string,
krb5_enctype *etype)
{
int i;
for(i = 0; i < num_etypes; i++)
if(strcasecmp(etypes[i]->name, string) == 0){
*etype = etypes[i]->type;
return 0;
}
krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %s not supported", ""),
string);
return KRB5_PROG_ETYPE_NOSUPP;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_enctype_to_keytype(krb5_context context,
krb5_enctype etype,
krb5_keytype *keytype)
{
struct encryption_type *e = _find_enctype(etype);
if(e == NULL) {
krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
etype);
return KRB5_PROG_ETYPE_NOSUPP;
}
*keytype = e->keytype->type; /* XXX */
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_enctype_valid(krb5_context context,
krb5_enctype etype)
{
struct encryption_type *e = _find_enctype(etype);
if(e == NULL) {
krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
etype);
return KRB5_PROG_ETYPE_NOSUPP;
}
if (e->flags & F_DISABLED) {
krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %s is disabled", ""),
e->name);
return KRB5_PROG_ETYPE_NOSUPP;
}
return 0;
}
/**
* Return the coresponding encryption type for a checksum type.
*
* @param context Kerberos context
* @param ctype The checksum type to get the result enctype for
* @param etype The returned encryption, when the matching etype is
* not found, etype is set to ETYPE_NULL.
*
* @return Return an error code for an failure or 0 on success.
* @ingroup krb5_crypto
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_cksumtype_to_enctype(krb5_context context,
krb5_cksumtype ctype,
krb5_enctype *etype)
{
int i;
*etype = ETYPE_NULL;
for(i = 0; i < num_etypes; i++) {
if(etypes[i]->keyed_checksum &&
etypes[i]->keyed_checksum->type == ctype)
{
*etype = etypes[i]->type;
return 0;
}
}
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("checksum type %d not supported", ""),
(int)ctype);
return KRB5_PROG_SUMTYPE_NOSUPP;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_cksumtype_valid(krb5_context context,
krb5_cksumtype ctype)
{
struct checksum_type *c = _find_checksum(ctype);
if (c == NULL) {
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("checksum type %d not supported", ""),
ctype);
return KRB5_PROG_SUMTYPE_NOSUPP;
}
if (c->flags & F_DISABLED) {
krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP,
N_("checksum type %s is disabled", ""),
c->name);
return KRB5_PROG_SUMTYPE_NOSUPP;
}
return 0;
}
static krb5_boolean
derived_crypto(krb5_context context,
krb5_crypto crypto)
{
return (crypto->et->flags & F_DERIVED) != 0;
}
static krb5_boolean
special_crypto(krb5_context context,
krb5_crypto crypto)
{
return (crypto->et->flags & F_SPECIAL) != 0;
}
#define CHECKSUMSIZE(C) ((C)->checksumsize)
#define CHECKSUMTYPE(C) ((C)->type)
static krb5_error_code
encrypt_internal_derived(krb5_context context,
krb5_crypto crypto,
unsigned usage,
const void *data,
size_t len,
krb5_data *result,
void *ivec)
{
size_t sz, block_sz, checksum_sz, total_sz;
Checksum cksum;
unsigned char *p, *q;
krb5_error_code ret;
struct key_data *dkey;
const struct encryption_type *et = crypto->et;
checksum_sz = CHECKSUMSIZE(et->keyed_checksum);
sz = et->confoundersize + len;
block_sz = (sz + et->padsize - 1) &~ (et->padsize - 1); /* pad */
total_sz = block_sz + checksum_sz;
p = calloc(1, total_sz);
if(p == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
q = p;
krb5_generate_random_block(q, et->confoundersize); /* XXX */
q += et->confoundersize;
memcpy(q, data, len);
ret = create_checksum(context,
et->keyed_checksum,
crypto,
INTEGRITY_USAGE(usage),
p,
block_sz,
&cksum);
if(ret == 0 && cksum.checksum.length != checksum_sz) {
free_Checksum (&cksum);
krb5_clear_error_message (context);
ret = KRB5_CRYPTO_INTERNAL;
}
if(ret)
goto fail;
memcpy(p + block_sz, cksum.checksum.data, cksum.checksum.length);
free_Checksum (&cksum);
ret = _get_derived_key(context, crypto, ENCRYPTION_USAGE(usage), &dkey);
if(ret)
goto fail;
ret = _key_schedule(context, dkey);
if(ret)
goto fail;
ret = (*et->encrypt)(context, dkey, p, block_sz, 1, usage, ivec);
if (ret)
goto fail;
result->data = p;
result->length = total_sz;
return 0;
fail:
memset(p, 0, total_sz);
free(p);
return ret;
}
static krb5_error_code
encrypt_internal(krb5_context context,
krb5_crypto crypto,
const void *data,
size_t len,
krb5_data *result,
void *ivec)
{
size_t sz, block_sz, checksum_sz;
Checksum cksum;
unsigned char *p, *q;
krb5_error_code ret;
const struct encryption_type *et = crypto->et;
checksum_sz = CHECKSUMSIZE(et->checksum);
sz = et->confoundersize + checksum_sz + len;
block_sz = (sz + et->padsize - 1) &~ (et->padsize - 1); /* pad */
p = calloc(1, block_sz);
if(p == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
q = p;
krb5_generate_random_block(q, et->confoundersize); /* XXX */
q += et->confoundersize;
memset(q, 0, checksum_sz);
q += checksum_sz;
memcpy(q, data, len);
ret = create_checksum(context,
et->checksum,
crypto,
0,
p,
block_sz,
&cksum);
if(ret == 0 && cksum.checksum.length != checksum_sz) {
krb5_clear_error_message (context);
free_Checksum(&cksum);
ret = KRB5_CRYPTO_INTERNAL;
}
if(ret)
goto fail;
memcpy(p + et->confoundersize, cksum.checksum.data, cksum.checksum.length);
free_Checksum(&cksum);
ret = _key_schedule(context, &crypto->key);
if(ret)
goto fail;
ret = (*et->encrypt)(context, &crypto->key, p, block_sz, 1, 0, ivec);
if (ret) {
memset(p, 0, block_sz);
free(p);
return ret;
}
result->data = p;
result->length = block_sz;
return 0;
fail:
memset(p, 0, block_sz);
free(p);
return ret;
}
static krb5_error_code
encrypt_internal_special(krb5_context context,
krb5_crypto crypto,
int usage,
const void *data,
size_t len,
krb5_data *result,
void *ivec)
{
struct encryption_type *et = crypto->et;
size_t cksum_sz = CHECKSUMSIZE(et->checksum);
size_t sz = len + cksum_sz + et->confoundersize;
char *tmp, *p;
krb5_error_code ret;
tmp = malloc (sz);
if (tmp == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
p = tmp;
memset (p, 0, cksum_sz);
p += cksum_sz;
krb5_generate_random_block(p, et->confoundersize);
p += et->confoundersize;
memcpy (p, data, len);
ret = (*et->encrypt)(context, &crypto->key, tmp, sz, TRUE, usage, ivec);
if (ret) {
memset(tmp, 0, sz);
free(tmp);
return ret;
}
result->data = tmp;
result->length = sz;
return 0;
}
static krb5_error_code
decrypt_internal_derived(krb5_context context,
krb5_crypto crypto,
unsigned usage,
void *data,
size_t len,
krb5_data *result,
void *ivec)
{
size_t checksum_sz;
Checksum cksum;
unsigned char *p;
krb5_error_code ret;
struct key_data *dkey;
struct encryption_type *et = crypto->et;
unsigned long l;
checksum_sz = CHECKSUMSIZE(et->keyed_checksum);
if (len < checksum_sz + et->confoundersize) {
krb5_set_error_message(context, KRB5_BAD_MSIZE,
N_("Encrypted data shorter then "
"checksum + confunder", ""));
return KRB5_BAD_MSIZE;
}
if (((len - checksum_sz) % et->padsize) != 0) {
krb5_clear_error_message(context);
return KRB5_BAD_MSIZE;
}
p = malloc(len);
if(len != 0 && p == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
memcpy(p, data, len);
len -= checksum_sz;
ret = _get_derived_key(context, crypto, ENCRYPTION_USAGE(usage), &dkey);
if(ret) {
free(p);
return ret;
}
ret = _key_schedule(context, dkey);
if(ret) {
free(p);
return ret;
}
ret = (*et->encrypt)(context, dkey, p, len, 0, usage, ivec);
if (ret) {
free(p);
return ret;
}
cksum.checksum.data = p + len;
cksum.checksum.length = checksum_sz;
cksum.cksumtype = CHECKSUMTYPE(et->keyed_checksum);
ret = verify_checksum(context,
crypto,
INTEGRITY_USAGE(usage),
p,
len,
&cksum);
if(ret) {
free(p);
return ret;
}
l = len - et->confoundersize;
memmove(p, p + et->confoundersize, l);
result->data = realloc(p, l);
if(result->data == NULL && l != 0) {
free(p);
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
result->length = l;
return 0;
}
static krb5_error_code
decrypt_internal(krb5_context context,
krb5_crypto crypto,
void *data,
size_t len,
krb5_data *result,
void *ivec)
{
krb5_error_code ret;
unsigned char *p;
Checksum cksum;
size_t checksum_sz, l;
struct encryption_type *et = crypto->et;
if ((len % et->padsize) != 0) {
krb5_clear_error_message(context);
return KRB5_BAD_MSIZE;
}
checksum_sz = CHECKSUMSIZE(et->checksum);
p = malloc(len);
if(len != 0 && p == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
memcpy(p, data, len);
ret = _key_schedule(context, &crypto->key);
if(ret) {
free(p);
return ret;
}
ret = (*et->encrypt)(context, &crypto->key, p, len, 0, 0, ivec);
if (ret) {
free(p);
return ret;
}
ret = krb5_data_copy(&cksum.checksum, p + et->confoundersize, checksum_sz);
if(ret) {
free(p);
return ret;
}
memset(p + et->confoundersize, 0, checksum_sz);
cksum.cksumtype = CHECKSUMTYPE(et->checksum);
ret = verify_checksum(context, NULL, 0, p, len, &cksum);
free_Checksum(&cksum);
if(ret) {
free(p);
return ret;
}
l = len - et->confoundersize - checksum_sz;
memmove(p, p + et->confoundersize + checksum_sz, l);
result->data = realloc(p, l);
if(result->data == NULL && l != 0) {
free(p);
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
result->length = l;
return 0;
}
static krb5_error_code
decrypt_internal_special(krb5_context context,
krb5_crypto crypto,
int usage,
void *data,
size_t len,
krb5_data *result,
void *ivec)
{
struct encryption_type *et = crypto->et;
size_t cksum_sz = CHECKSUMSIZE(et->checksum);
size_t sz = len - cksum_sz - et->confoundersize;
unsigned char *p;
krb5_error_code ret;
if ((len % et->padsize) != 0) {
krb5_clear_error_message(context);
return KRB5_BAD_MSIZE;
}
p = malloc (len);
if (p == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
memcpy(p, data, len);
ret = (*et->encrypt)(context, &crypto->key, p, len, FALSE, usage, ivec);
if (ret) {
free(p);
return ret;
}
memmove (p, p + cksum_sz + et->confoundersize, sz);
result->data = realloc(p, sz);
if(result->data == NULL && sz != 0) {
free(p);
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
result->length = sz;
return 0;
}
static krb5_crypto_iov *
find_iv(krb5_crypto_iov *data, int num_data, int type)
{
int i;
for (i = 0; i < num_data; i++)
if (data[i].flags == type)
return &data[i];
return NULL;
}
/**
* Inline encrypt a kerberos message
*
* @param context Kerberos context
* @param crypto Kerberos crypto context
* @param usage Key usage for this buffer
* @param data array of buffers to process
* @param num_data length of array
* @param ivec initial cbc/cts vector
*
* @return Return an error code or 0.
* @ingroup krb5_crypto
*
* Kerberos encrypted data look like this:
*
* 1. KRB5_CRYPTO_TYPE_HEADER
* 2. array [1,...] KRB5_CRYPTO_TYPE_DATA and array [0,...]
* KRB5_CRYPTO_TYPE_SIGN_ONLY in any order, however the receiver
* have to aware of the order. KRB5_CRYPTO_TYPE_SIGN_ONLY is
* commonly used headers and trailers.
* 3. KRB5_CRYPTO_TYPE_PADDING, at least on padsize long if padsize > 1
* 4. KRB5_CRYPTO_TYPE_TRAILER
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_encrypt_iov_ivec(krb5_context context,
krb5_crypto crypto,
unsigned usage,
krb5_crypto_iov *data,
int num_data,
void *ivec)
{
size_t headersz, trailersz, len;
int i;
size_t sz, block_sz, pad_sz;
Checksum cksum;
unsigned char *p, *q;
krb5_error_code ret;
struct key_data *dkey;
const struct encryption_type *et = crypto->et;
krb5_crypto_iov *tiv, *piv, *hiv;
if (num_data < 0) {
krb5_clear_error_message(context);
return KRB5_CRYPTO_INTERNAL;
}
if(!derived_crypto(context, crypto)) {
krb5_clear_error_message(context);
return KRB5_CRYPTO_INTERNAL;
}
headersz = et->confoundersize;
trailersz = CHECKSUMSIZE(et->keyed_checksum);
for (len = 0, i = 0; i < num_data; i++) {
if (data[i].flags != KRB5_CRYPTO_TYPE_DATA)
continue;
len += data[i].data.length;
}
sz = headersz + len;
block_sz = (sz + et->padsize - 1) &~ (et->padsize - 1); /* pad */
pad_sz = block_sz - sz;
/* header */
hiv = find_iv(data, num_data, KRB5_CRYPTO_TYPE_HEADER);
if (hiv == NULL || hiv->data.length != headersz)
return KRB5_BAD_MSIZE;
krb5_generate_random_block(hiv->data.data, hiv->data.length);
/* padding */
piv = find_iv(data, num_data, KRB5_CRYPTO_TYPE_PADDING);
/* its ok to have no TYPE_PADDING if there is no padding */
if (piv == NULL && pad_sz != 0)
return KRB5_BAD_MSIZE;
if (piv) {
if (piv->data.length < pad_sz)
return KRB5_BAD_MSIZE;
piv->data.length = pad_sz;
if (pad_sz)
memset(piv->data.data, pad_sz, pad_sz);
else
piv = NULL;
}
/* trailer */
tiv = find_iv(data, num_data, KRB5_CRYPTO_TYPE_TRAILER);
if (tiv == NULL || tiv->data.length != trailersz)
return KRB5_BAD_MSIZE;
/*
* XXX replace with EVP_Sign? at least make create_checksum an iov
* function.
* XXX CTS EVP is broken, can't handle multi buffers :(
*/
len = block_sz;
for (i = 0; i < num_data; i++) {
if (data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY)
continue;
len += data[i].data.length;
}
p = q = malloc(len);
memcpy(q, hiv->data.data, hiv->data.length);
q += hiv->data.length;
for (i = 0; i < num_data; i++) {
if (data[i].flags != KRB5_CRYPTO_TYPE_DATA &&
data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY)
continue;
memcpy(q, data[i].data.data, data[i].data.length);
q += data[i].data.length;
}
if (piv)
memset(q, 0, piv->data.length);
ret = create_checksum(context,
et->keyed_checksum,
crypto,
INTEGRITY_USAGE(usage),
p,
len,
&cksum);
free(p);
if(ret == 0 && cksum.checksum.length != trailersz) {
free_Checksum (&cksum);
krb5_clear_error_message (context);
ret = KRB5_CRYPTO_INTERNAL;
}
if(ret)
return ret;
/* save cksum at end */
memcpy(tiv->data.data, cksum.checksum.data, cksum.checksum.length);
free_Checksum (&cksum);
/* XXX replace with EVP_Cipher */
p = q = malloc(block_sz);
if(p == NULL)
return ENOMEM;
memcpy(q, hiv->data.data, hiv->data.length);
q += hiv->data.length;
for (i = 0; i < num_data; i++) {
if (data[i].flags != KRB5_CRYPTO_TYPE_DATA)
continue;
memcpy(q, data[i].data.data, data[i].data.length);
q += data[i].data.length;
}
if (piv)
memset(q, 0, piv->data.length);
ret = _get_derived_key(context, crypto, ENCRYPTION_USAGE(usage), &dkey);
if(ret) {
free(p);
return ret;
}
ret = _key_schedule(context, dkey);
if(ret) {
free(p);
return ret;
}
ret = (*et->encrypt)(context, dkey, p, block_sz, 1, usage, ivec);
if (ret) {
free(p);
return ret;
}
/* now copy data back to buffers */
q = p;
memcpy(hiv->data.data, q, hiv->data.length);
q += hiv->data.length;
for (i = 0; i < num_data; i++) {
if (data[i].flags != KRB5_CRYPTO_TYPE_DATA)
continue;
memcpy(data[i].data.data, q, data[i].data.length);
q += data[i].data.length;
}
if (piv)
memcpy(piv->data.data, q, pad_sz);
free(p);
return ret;
}
/**
* Inline decrypt a Kerberos message.
*
* @param context Kerberos context
* @param crypto Kerberos crypto context
* @param usage Key usage for this buffer
* @param data array of buffers to process
* @param num_data length of array
* @param ivec initial cbc/cts vector
*
* @return Return an error code or 0.
* @ingroup krb5_crypto
*
* 1. KRB5_CRYPTO_TYPE_HEADER
* 2. one KRB5_CRYPTO_TYPE_DATA and array [0,...] of KRB5_CRYPTO_TYPE_SIGN_ONLY in
* any order, however the receiver have to aware of the
* order. KRB5_CRYPTO_TYPE_SIGN_ONLY is commonly used unencrypoted
* protocol headers and trailers. The output data will be of same
* size as the input data or shorter.
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_decrypt_iov_ivec(krb5_context context,
krb5_crypto crypto,
unsigned usage,
krb5_crypto_iov *data,
unsigned int num_data,
void *ivec)
{
unsigned int i;
size_t headersz, trailersz, len;
Checksum cksum;
unsigned char *p, *q;
krb5_error_code ret;
struct key_data *dkey;
struct encryption_type *et = crypto->et;
krb5_crypto_iov *tiv, *hiv;
if (num_data < 0) {
krb5_clear_error_message(context);
return KRB5_CRYPTO_INTERNAL;
}
if(!derived_crypto(context, crypto)) {
krb5_clear_error_message(context);
return KRB5_CRYPTO_INTERNAL;
}
headersz = et->confoundersize;
hiv = find_iv(data, num_data, KRB5_CRYPTO_TYPE_HEADER);
if (hiv == NULL || hiv->data.length != headersz)
return KRB5_BAD_MSIZE;
/* trailer */
trailersz = CHECKSUMSIZE(et->keyed_checksum);
tiv = find_iv(data, num_data, KRB5_CRYPTO_TYPE_TRAILER);
if (tiv->data.length != trailersz)
return KRB5_BAD_MSIZE;
/* Find length of data we will decrypt */
len = headersz;
for (i = 0; i < num_data; i++) {
if (data[i].flags != KRB5_CRYPTO_TYPE_DATA)
continue;
len += data[i].data.length;
}
if ((len % et->padsize) != 0) {
krb5_clear_error_message(context);
return KRB5_BAD_MSIZE;
}
/* XXX replace with EVP_Cipher */
p = q = malloc(len);
if (p == NULL)
return ENOMEM;
memcpy(q, hiv->data.data, hiv->data.length);
q += hiv->data.length;
for (i = 0; i < num_data; i++) {
if (data[i].flags != KRB5_CRYPTO_TYPE_DATA)
continue;
memcpy(q, data[i].data.data, data[i].data.length);
q += data[i].data.length;
}
ret = _get_derived_key(context, crypto, ENCRYPTION_USAGE(usage), &dkey);
if(ret) {
free(p);
return ret;
}
ret = _key_schedule(context, dkey);
if(ret) {
free(p);
return ret;
}
ret = (*et->encrypt)(context, dkey, p, len, 0, usage, ivec);
if (ret) {
free(p);
return ret;
}
/* copy data back to buffers */
memcpy(hiv->data.data, p, hiv->data.length);
q = p + hiv->data.length;
for (i = 0; i < num_data; i++) {
if (data[i].flags != KRB5_CRYPTO_TYPE_DATA)
continue;
memcpy(data[i].data.data, q, data[i].data.length);
q += data[i].data.length;
}
free(p);
/* check signature */
for (i = 0; i < num_data; i++) {
if (data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY)
continue;
len += data[i].data.length;
}
p = q = malloc(len);
if (p == NULL)
return ENOMEM;
memcpy(q, hiv->data.data, hiv->data.length);
q += hiv->data.length;
for (i = 0; i < num_data; i++) {
if (data[i].flags != KRB5_CRYPTO_TYPE_DATA &&
data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY)
continue;
memcpy(q, data[i].data.data, data[i].data.length);
q += data[i].data.length;
}
cksum.checksum.data = tiv->data.data;
cksum.checksum.length = tiv->data.length;
cksum.cksumtype = CHECKSUMTYPE(et->keyed_checksum);
ret = verify_checksum(context,
crypto,
INTEGRITY_USAGE(usage),
p,
len,
&cksum);
free(p);
return ret;
}
/**
* Create a Kerberos message checksum.
*
* @param context Kerberos context
* @param crypto Kerberos crypto context
* @param usage Key usage for this buffer
* @param data array of buffers to process
* @param num_data length of array
* @param type output data
*
* @return Return an error code or 0.
* @ingroup krb5_crypto
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_create_checksum_iov(krb5_context context,
krb5_crypto crypto,
unsigned usage,
krb5_crypto_iov *data,
unsigned int num_data,
krb5_cksumtype *type)
{
Checksum cksum;
krb5_crypto_iov *civ;
krb5_error_code ret;
int i;
size_t len;
char *p, *q;
if (num_data < 0) {
krb5_clear_error_message(context);
return KRB5_CRYPTO_INTERNAL;
}
if(!derived_crypto(context, crypto)) {
krb5_clear_error_message(context);
return KRB5_CRYPTO_INTERNAL;
}
civ = find_iv(data, num_data, KRB5_CRYPTO_TYPE_CHECKSUM);
if (civ == NULL)
return KRB5_BAD_MSIZE;
len = 0;
for (i = 0; i < num_data; i++) {
if (data[i].flags != KRB5_CRYPTO_TYPE_DATA &&
data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY)
continue;
len += data[i].data.length;
}
p = q = malloc(len);
for (i = 0; i < num_data; i++) {
if (data[i].flags != KRB5_CRYPTO_TYPE_DATA &&
data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY)
continue;
memcpy(q, data[i].data.data, data[i].data.length);
q += data[i].data.length;
}
ret = krb5_create_checksum(context, crypto, usage, 0, p, len, &cksum);
free(p);
if (ret)
return ret;
if (type)
*type = cksum.cksumtype;
if (cksum.checksum.length > civ->data.length) {
krb5_set_error_message(context, KRB5_BAD_MSIZE,
N_("Checksum larger then input buffer", ""));
free_Checksum(&cksum);
return KRB5_BAD_MSIZE;
}
civ->data.length = cksum.checksum.length;
memcpy(civ->data.data, cksum.checksum.data, civ->data.length);
free_Checksum(&cksum);
return 0;
}
/**
* Verify a Kerberos message checksum.
*
* @param context Kerberos context
* @param crypto Kerberos crypto context
* @param usage Key usage for this buffer
* @param data array of buffers to process
* @param num_data length of array
* @param type return checksum type if not NULL
*
* @return Return an error code or 0.
* @ingroup krb5_crypto
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_verify_checksum_iov(krb5_context context,
krb5_crypto crypto,
unsigned usage,
krb5_crypto_iov *data,
unsigned int num_data,
krb5_cksumtype *type)
{
struct encryption_type *et = crypto->et;
Checksum cksum;
krb5_crypto_iov *civ;
krb5_error_code ret;
int i;
size_t len;
char *p, *q;
if (num_data < 0) {
krb5_clear_error_message(context);
return KRB5_CRYPTO_INTERNAL;
}
if(!derived_crypto(context, crypto)) {
krb5_clear_error_message(context);
return KRB5_CRYPTO_INTERNAL;
}
civ = find_iv(data, num_data, KRB5_CRYPTO_TYPE_CHECKSUM);
if (civ == NULL)
return KRB5_BAD_MSIZE;
len = 0;
for (i = 0; i < num_data; i++) {
if (data[i].flags != KRB5_CRYPTO_TYPE_DATA &&
data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY)
continue;
len += data[i].data.length;
}
p = q = malloc(len);
for (i = 0; i < num_data; i++) {
if (data[i].flags != KRB5_CRYPTO_TYPE_DATA &&
data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY)
continue;
memcpy(q, data[i].data.data, data[i].data.length);
q += data[i].data.length;
}
cksum.cksumtype = CHECKSUMTYPE(et->keyed_checksum);
cksum.checksum.length = civ->data.length;
cksum.checksum.data = civ->data.data;
ret = krb5_verify_checksum(context, crypto, usage, p, len, &cksum);
free(p);
if (ret == 0 && type)
*type = cksum.cksumtype;
return ret;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_crypto_length(krb5_context context,
krb5_crypto crypto,
int type,
size_t *len)
{
if (!derived_crypto(context, crypto)) {
krb5_set_error_message(context, EINVAL, "not a derived crypto");
return EINVAL;
}
switch(type) {
case KRB5_CRYPTO_TYPE_EMPTY:
*len = 0;
return 0;
case KRB5_CRYPTO_TYPE_HEADER:
*len = crypto->et->blocksize;
return 0;
case KRB5_CRYPTO_TYPE_DATA:
case KRB5_CRYPTO_TYPE_SIGN_ONLY:
/* len must already been filled in */
return 0;
case KRB5_CRYPTO_TYPE_PADDING:
if (crypto->et->padsize > 1)
*len = crypto->et->padsize;
else
*len = 0;
return 0;
case KRB5_CRYPTO_TYPE_TRAILER:
*len = CHECKSUMSIZE(crypto->et->keyed_checksum);
return 0;
case KRB5_CRYPTO_TYPE_CHECKSUM:
if (crypto->et->keyed_checksum)
*len = CHECKSUMSIZE(crypto->et->keyed_checksum);
else
*len = CHECKSUMSIZE(crypto->et->checksum);
return 0;
}
krb5_set_error_message(context, EINVAL,
"%d not a supported type", type);
return EINVAL;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_crypto_length_iov(krb5_context context,
krb5_crypto crypto,
krb5_crypto_iov *data,
unsigned int num_data)
{
krb5_error_code ret;
int i;
for (i = 0; i < num_data; i++) {
ret = krb5_crypto_length(context, crypto,
data[i].flags,
&data[i].data.length);
if (ret)
return ret;
}
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_encrypt_ivec(krb5_context context,
krb5_crypto crypto,
unsigned usage,
const void *data,
size_t len,
krb5_data *result,
void *ivec)
{
if(derived_crypto(context, crypto))
return encrypt_internal_derived(context, crypto, usage,
data, len, result, ivec);
else if (special_crypto(context, crypto))
return encrypt_internal_special (context, crypto, usage,
data, len, result, ivec);
else
return encrypt_internal(context, crypto, data, len, result, ivec);
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_encrypt(krb5_context context,
krb5_crypto crypto,
unsigned usage,
const void *data,
size_t len,
krb5_data *result)
{
return krb5_encrypt_ivec(context, crypto, usage, data, len, result, NULL);
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_encrypt_EncryptedData(krb5_context context,
krb5_crypto crypto,
unsigned usage,
void *data,
size_t len,
int kvno,
EncryptedData *result)
{
result->etype = CRYPTO_ETYPE(crypto);
if(kvno){
ALLOC(result->kvno, 1);
*result->kvno = kvno;
}else
result->kvno = NULL;
return krb5_encrypt(context, crypto, usage, data, len, &result->cipher);
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_decrypt_ivec(krb5_context context,
krb5_crypto crypto,
unsigned usage,
void *data,
size_t len,
krb5_data *result,
void *ivec)
{
if(derived_crypto(context, crypto))
return decrypt_internal_derived(context, crypto, usage,
data, len, result, ivec);
else if (special_crypto (context, crypto))
return decrypt_internal_special(context, crypto, usage,
data, len, result, ivec);
else
return decrypt_internal(context, crypto, data, len, result, ivec);
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_decrypt(krb5_context context,
krb5_crypto crypto,
unsigned usage,
void *data,
size_t len,
krb5_data *result)
{
return krb5_decrypt_ivec (context, crypto, usage, data, len, result,
NULL);
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_decrypt_EncryptedData(krb5_context context,
krb5_crypto crypto,
unsigned usage,
const EncryptedData *e,
krb5_data *result)
{
return krb5_decrypt(context, crypto, usage,
e->cipher.data, e->cipher.length, result);
}
/************************************************************
* *
************************************************************/
#define ENTROPY_NEEDED 128
static int
seed_something(void)
{
char buf[1024], seedfile[256];
/* If there is a seed file, load it. But such a file cannot be trusted,
so use 0 for the entropy estimate */
if (RAND_file_name(seedfile, sizeof(seedfile))) {
int fd;
fd = open(seedfile, O_RDONLY | O_BINARY | O_CLOEXEC);
if (fd >= 0) {
ssize_t ret;
rk_cloexec(fd);
ret = read(fd, buf, sizeof(buf));
if (ret > 0)
RAND_add(buf, ret, 0.0);
close(fd);
} else
seedfile[0] = '\0';
} else
seedfile[0] = '\0';
/* Calling RAND_status() will try to use /dev/urandom if it exists so
we do not have to deal with it. */
if (RAND_status() != 1) {
#ifndef _WIN32
krb5_context context;
const char *p;
/* Try using egd */
if (!krb5_init_context(&context)) {
p = krb5_config_get_string(context, NULL, "libdefaults",
"egd_socket", NULL);
if (p != NULL)
RAND_egd_bytes(p, ENTROPY_NEEDED);
krb5_free_context(context);
}
#else
/* TODO: Once a Windows CryptoAPI RAND method is defined, we
can use that and failover to another method. */
#endif
}
if (RAND_status() == 1) {
/* Update the seed file */
if (seedfile[0])
RAND_write_file(seedfile);
return 0;
} else
return -1;
}
KRB5_LIB_FUNCTION void KRB5_LIB_CALL
krb5_generate_random_block(void *buf, size_t len)
{
static int rng_initialized = 0;
HEIMDAL_MUTEX_lock(&crypto_mutex);
if (!rng_initialized) {
if (seed_something())
krb5_abortx(NULL, "Fatal: could not seed the "
"random number generator");
rng_initialized = 1;
}
HEIMDAL_MUTEX_unlock(&crypto_mutex);
if (RAND_bytes(buf, len) != 1)
krb5_abortx(NULL, "Failed to generate random block");
}
static krb5_error_code
derive_key(krb5_context context,
struct encryption_type *et,
struct key_data *key,
const void *constant,
size_t len)
{
unsigned char *k = NULL;
unsigned int nblocks = 0, i;
krb5_error_code ret = 0;
struct key_type *kt = et->keytype;
ret = _key_schedule(context, key);
if(ret)
return ret;
if(et->blocksize * 8 < kt->bits || len != et->blocksize) {
nblocks = (kt->bits + et->blocksize * 8 - 1) / (et->blocksize * 8);
k = malloc(nblocks * et->blocksize);
if(k == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
goto out;
}
ret = _krb5_n_fold(constant, len, k, et->blocksize);
if (ret) {
krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
goto out;
}
for(i = 0; i < nblocks; i++) {
if(i > 0)
memcpy(k + i * et->blocksize,
k + (i - 1) * et->blocksize,
et->blocksize);
(*et->encrypt)(context, key, k + i * et->blocksize, et->blocksize,
1, 0, NULL);
}
} else {
/* this case is probably broken, but won't be run anyway */
void *c = malloc(len);
size_t res_len = (kt->bits + 7) / 8;
if(len != 0 && c == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
goto out;
}
memcpy(c, constant, len);
(*et->encrypt)(context, key, c, len, 1, 0, NULL);
k = malloc(res_len);
if(res_len != 0 && k == NULL) {
free(c);
ret = ENOMEM;
krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
goto out;
}
ret = _krb5_n_fold(c, len, k, res_len);
free(c);
if (ret) {
krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
goto out;
}
}
/* XXX keytype dependent post-processing */
switch(kt->type) {
case KEYTYPE_DES3:
DES3_random_to_key(context, key->key, k, nblocks * et->blocksize);
break;
case KEYTYPE_AES128:
case KEYTYPE_AES256:
memcpy(key->key->keyvalue.data, k, key->key->keyvalue.length);
break;
default:
ret = KRB5_CRYPTO_INTERNAL;
krb5_set_error_message(context, ret,
N_("derive_key() called with unknown keytype (%u)", ""),
kt->type);
break;
}
out:
if (key->schedule) {
free_key_schedule(context, key, et);
key->schedule = NULL;
}
if (k) {
memset(k, 0, nblocks * et->blocksize);
free(k);
}
return ret;
}
static struct key_data *
_new_derived_key(krb5_crypto crypto, unsigned usage)
{
struct key_usage *d = crypto->key_usage;
d = realloc(d, (crypto->num_key_usage + 1) * sizeof(*d));
if(d == NULL)
return NULL;
crypto->key_usage = d;
d += crypto->num_key_usage++;
memset(d, 0, sizeof(*d));
d->usage = usage;
return &d->key;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_derive_key(krb5_context context,
const krb5_keyblock *key,
krb5_enctype etype,
const void *constant,
size_t constant_len,
krb5_keyblock **derived_key)
{
krb5_error_code ret;
struct encryption_type *et;
struct key_data d;
*derived_key = NULL;
et = _find_enctype (etype);
if (et == NULL) {
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
etype);
return KRB5_PROG_ETYPE_NOSUPP;
}
ret = krb5_copy_keyblock(context, key, &d.key);
if (ret)
return ret;
d.schedule = NULL;
ret = derive_key(context, et, &d, constant, constant_len);
if (ret == 0)
ret = krb5_copy_keyblock(context, d.key, derived_key);
free_key_data(context, &d, et);
return ret;
}
static krb5_error_code
_get_derived_key(krb5_context context,
krb5_crypto crypto,
unsigned usage,
struct key_data **key)
{
int i;
struct key_data *d;
unsigned char constant[5];
for(i = 0; i < crypto->num_key_usage; i++)
if(crypto->key_usage[i].usage == usage) {
*key = &crypto->key_usage[i].key;
return 0;
}
d = _new_derived_key(crypto, usage);
if(d == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
krb5_copy_keyblock(context, crypto->key.key, &d->key);
_krb5_put_int(constant, usage, 5);
derive_key(context, crypto->et, d, constant, sizeof(constant));
*key = d;
return 0;
}
/**
* Create a crypto context used for all encryption and signature
* operation. The encryption type to use is taken from the key, but
* can be overridden with the enctype parameter. This can be useful
* for encryptions types which is compatiable (DES for example).
*
* To free the crypto context, use krb5_crypto_destroy().
*
* @param context Kerberos context
* @param key the key block information with all key data
* @param etype the encryption type
* @param crypto the resulting crypto context
*
* @return Return an error code or 0.
*
* @ingroup krb5_crypto
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_crypto_init(krb5_context context,
const krb5_keyblock *key,
krb5_enctype etype,
krb5_crypto *crypto)
{
krb5_error_code ret;
ALLOC(*crypto, 1);
if(*crypto == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
if(etype == ETYPE_NULL)
etype = key->keytype;
(*crypto)->et = _find_enctype(etype);
if((*crypto)->et == NULL || ((*crypto)->et->flags & F_DISABLED)) {
free(*crypto);
*crypto = NULL;
krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
etype);
return KRB5_PROG_ETYPE_NOSUPP;
}
if((*crypto)->et->keytype->size != key->keyvalue.length) {
free(*crypto);
*crypto = NULL;
krb5_set_error_message (context, KRB5_BAD_KEYSIZE,
"encryption key has bad length");
return KRB5_BAD_KEYSIZE;
}
ret = krb5_copy_keyblock(context, key, &(*crypto)->key.key);
if(ret) {
free(*crypto);
*crypto = NULL;
return ret;
}
(*crypto)->key.schedule = NULL;
(*crypto)->num_key_usage = 0;
(*crypto)->key_usage = NULL;
return 0;
}
static void
free_key_schedule(krb5_context context,
struct key_data *key,
struct encryption_type *et)
{
if (et->keytype->cleanup)
(*et->keytype->cleanup)(context, key);
memset(key->schedule->data, 0, key->schedule->length);
krb5_free_data(context, key->schedule);
}
static void
free_key_data(krb5_context context, struct key_data *key,
struct encryption_type *et)
{
krb5_free_keyblock(context, key->key);
if(key->schedule) {
free_key_schedule(context, key, et);
key->schedule = NULL;
}
}
static void
free_key_usage(krb5_context context, struct key_usage *ku,
struct encryption_type *et)
{
free_key_data(context, &ku->key, et);
}
/**
* Free a crypto context created by krb5_crypto_init().
*
* @param context Kerberos context
* @param crypto crypto context to free
*
* @return Return an error code or 0.
*
* @ingroup krb5_crypto
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_crypto_destroy(krb5_context context,
krb5_crypto crypto)
{
int i;
for(i = 0; i < crypto->num_key_usage; i++)
free_key_usage(context, &crypto->key_usage[i], crypto->et);
free(crypto->key_usage);
free_key_data(context, &crypto->key, crypto->et);
free (crypto);
return 0;
}
/**
* Return the blocksize used algorithm referenced by the crypto context
*
* @param context Kerberos context
* @param crypto crypto context to query
* @param blocksize the resulting blocksize
*
* @return Return an error code or 0.
*
* @ingroup krb5_crypto
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_crypto_getblocksize(krb5_context context,
krb5_crypto crypto,
size_t *blocksize)
{
*blocksize = crypto->et->blocksize;
return 0;
}
/**
* Return the encryption type used by the crypto context
*
* @param context Kerberos context
* @param crypto crypto context to query
* @param enctype the resulting encryption type
*
* @return Return an error code or 0.
*
* @ingroup krb5_crypto
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_crypto_getenctype(krb5_context context,
krb5_crypto crypto,
krb5_enctype *enctype)
{
*enctype = crypto->et->type;
return 0;
}
/**
* Return the padding size used by the crypto context
*
* @param context Kerberos context
* @param crypto crypto context to query
* @param padsize the return padding size
*
* @return Return an error code or 0.
*
* @ingroup krb5_crypto
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_crypto_getpadsize(krb5_context context,
krb5_crypto crypto,
size_t *padsize)
{
*padsize = crypto->et->padsize;
return 0;
}
/**
* Return the confounder size used by the crypto context
*
* @param context Kerberos context
* @param crypto crypto context to query
* @param confoundersize the returned confounder size
*
* @return Return an error code or 0.
*
* @ingroup krb5_crypto
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_crypto_getconfoundersize(krb5_context context,
krb5_crypto crypto,
size_t *confoundersize)
{
*confoundersize = crypto->et->confoundersize;
return 0;
}
/**
* Disable encryption type
*
* @param context Kerberos 5 context
* @param enctype encryption type to disable
*
* @return Return an error code or 0.
*
* @ingroup krb5_crypto
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_enctype_disable(krb5_context context,
krb5_enctype enctype)
{
struct encryption_type *et = _find_enctype(enctype);
if(et == NULL) {
if (context)
krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
enctype);
return KRB5_PROG_ETYPE_NOSUPP;
}
et->flags |= F_DISABLED;
return 0;
}
/**
* Enable encryption type
*
* @param context Kerberos 5 context
* @param enctype encryption type to enable
*
* @return Return an error code or 0.
*
* @ingroup krb5_crypto
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_enctype_enable(krb5_context context,
krb5_enctype enctype)
{
struct encryption_type *et = _find_enctype(enctype);
if(et == NULL) {
if (context)
krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
enctype);
return KRB5_PROG_ETYPE_NOSUPP;
}
et->flags &= ~F_DISABLED;
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_string_to_key_derived(krb5_context context,
const void *str,
size_t len,
krb5_enctype etype,
krb5_keyblock *key)
{
struct encryption_type *et = _find_enctype(etype);
krb5_error_code ret;
struct key_data kd;
size_t keylen;
u_char *tmp;
if(et == NULL) {
krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
etype);
return KRB5_PROG_ETYPE_NOSUPP;
}
keylen = et->keytype->bits / 8;
ALLOC(kd.key, 1);
if(kd.key == NULL) {
krb5_set_error_message (context, ENOMEM,
N_("malloc: out of memory", ""));
return ENOMEM;
}
ret = krb5_data_alloc(&kd.key->keyvalue, et->keytype->size);
if(ret) {
free(kd.key);
return ret;
}
kd.key->keytype = etype;
tmp = malloc (keylen);
if(tmp == NULL) {
krb5_free_keyblock(context, kd.key);
krb5_set_error_message (context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
ret = _krb5_n_fold(str, len, tmp, keylen);
if (ret) {
free(tmp);
krb5_set_error_message (context, ENOMEM, N_("malloc: out of memory", ""));
return ret;
}
kd.schedule = NULL;
DES3_random_to_key(context, kd.key, tmp, keylen);
memset(tmp, 0, keylen);
free(tmp);
ret = derive_key(context,
et,
&kd,
"kerberos", /* XXX well known constant */
strlen("kerberos"));
if (ret) {
free_key_data(context, &kd, et);
return ret;
}
ret = krb5_copy_keyblock_contents(context, kd.key, key);
free_key_data(context, &kd, et);
return ret;
}
static size_t
wrapped_length (krb5_context context,
krb5_crypto crypto,
size_t data_len)
{
struct encryption_type *et = crypto->et;
size_t padsize = et->padsize;
size_t checksumsize = CHECKSUMSIZE(et->checksum);
size_t res;
res = et->confoundersize + checksumsize + data_len;
res = (res + padsize - 1) / padsize * padsize;
return res;
}
static size_t
wrapped_length_dervied (krb5_context context,
krb5_crypto crypto,
size_t data_len)
{
struct encryption_type *et = crypto->et;
size_t padsize = et->padsize;
size_t res;
res = et->confoundersize + data_len;
res = (res + padsize - 1) / padsize * padsize;
if (et->keyed_checksum)
res += et->keyed_checksum->checksumsize;
else
res += et->checksum->checksumsize;
return res;
}
/*
* Return the size of an encrypted packet of length `data_len'
*/
size_t
krb5_get_wrapped_length (krb5_context context,
krb5_crypto crypto,
size_t data_len)
{
if (derived_crypto (context, crypto))
return wrapped_length_dervied (context, crypto, data_len);
else
return wrapped_length (context, crypto, data_len);
}
/*
* Return the size of an encrypted packet of length `data_len'
*/
static size_t
crypto_overhead (krb5_context context,
krb5_crypto crypto)
{
struct encryption_type *et = crypto->et;
size_t res;
res = CHECKSUMSIZE(et->checksum);
res += et->confoundersize;
if (et->padsize > 1)
res += et->padsize;
return res;
}
static size_t
crypto_overhead_dervied (krb5_context context,
krb5_crypto crypto)
{
struct encryption_type *et = crypto->et;
size_t res;
if (et->keyed_checksum)
res = CHECKSUMSIZE(et->keyed_checksum);
else
res = CHECKSUMSIZE(et->checksum);
res += et->confoundersize;
if (et->padsize > 1)
res += et->padsize;
return res;
}
size_t
krb5_crypto_overhead (krb5_context context, krb5_crypto crypto)
{
if (derived_crypto (context, crypto))
return crypto_overhead_dervied (context, crypto);
else
return crypto_overhead (context, crypto);
}
/**
* Converts the random bytestring to a protocol key according to
* Kerberos crypto frame work. It may be assumed that all the bits of
* the input string are equally random, even though the entropy
* present in the random source may be limited.
*
* @param context Kerberos 5 context
* @param type the enctype resulting key will be of
* @param data input random data to convert to a key
* @param size size of input random data, at least krb5_enctype_keysize() long
* @param key key, output key, free with krb5_free_keyblock_contents()
*
* @return Return an error code or 0.
*
* @ingroup krb5_crypto
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_random_to_key(krb5_context context,
krb5_enctype type,
const void *data,
size_t size,
krb5_keyblock *key)
{
krb5_error_code ret;
struct encryption_type *et = _find_enctype(type);
if(et == NULL) {
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
type);
return KRB5_PROG_ETYPE_NOSUPP;
}
if ((et->keytype->bits + 7) / 8 > size) {
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption key %s needs %d bytes "
"of random to make an encryption key "
"out of it", ""),
et->name, (int)et->keytype->size);
return KRB5_PROG_ETYPE_NOSUPP;
}
ret = krb5_data_alloc(&key->keyvalue, et->keytype->size);
if(ret)
return ret;
key->keytype = type;
if (et->keytype->random_to_key)
(*et->keytype->random_to_key)(context, key, data, size);
else
memcpy(key->keyvalue.data, data, et->keytype->size);
return 0;
}
krb5_error_code
_krb5_pk_octetstring2key(krb5_context context,
krb5_enctype type,
const void *dhdata,
size_t dhsize,
const heim_octet_string *c_n,
const heim_octet_string *k_n,
krb5_keyblock *key)
{
struct encryption_type *et = _find_enctype(type);
krb5_error_code ret;
size_t keylen, offset;
void *keydata;
unsigned char counter;
unsigned char shaoutput[SHA_DIGEST_LENGTH];
EVP_MD_CTX *m;
if(et == NULL) {
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
type);
return KRB5_PROG_ETYPE_NOSUPP;
}
keylen = (et->keytype->bits + 7) / 8;
keydata = malloc(keylen);
if (keydata == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
m = EVP_MD_CTX_create();
if (m == NULL) {
free(keydata);
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
counter = 0;
offset = 0;
do {
EVP_DigestInit_ex(m, EVP_sha1(), NULL);
EVP_DigestUpdate(m, &counter, 1);
EVP_DigestUpdate(m, dhdata, dhsize);
if (c_n)
EVP_DigestUpdate(m, c_n->data, c_n->length);
if (k_n)
EVP_DigestUpdate(m, k_n->data, k_n->length);
EVP_DigestFinal_ex(m, shaoutput, NULL);
memcpy((unsigned char *)keydata + offset,
shaoutput,
min(keylen - offset, sizeof(shaoutput)));
offset += sizeof(shaoutput);
counter++;
} while(offset < keylen);
memset(shaoutput, 0, sizeof(shaoutput));
EVP_MD_CTX_destroy(m);
ret = krb5_random_to_key(context, type, keydata, keylen, key);
memset(keydata, 0, sizeof(keylen));
free(keydata);
return ret;
}
static krb5_error_code
encode_uvinfo(krb5_context context, krb5_const_principal p, krb5_data *data)
{
KRB5PrincipalName pn;
krb5_error_code ret;
size_t size;
pn.principalName = p->name;
pn.realm = p->realm;
ASN1_MALLOC_ENCODE(KRB5PrincipalName, data->data, data->length,
&pn, &size, ret);
if (ret) {
krb5_data_zero(data);
krb5_set_error_message(context, ret,
N_("Failed to encode KRB5PrincipalName", ""));
return ret;
}
if (data->length != size)
krb5_abortx(context, "asn1 compiler internal error");
return 0;
}
static krb5_error_code
encode_otherinfo(krb5_context context,
const AlgorithmIdentifier *ai,
krb5_const_principal client,
krb5_const_principal server,
krb5_enctype enctype,
const krb5_data *as_req,
const krb5_data *pk_as_rep,
const Ticket *ticket,
krb5_data *other)
{
PkinitSP80056AOtherInfo otherinfo;
PkinitSuppPubInfo pubinfo;
krb5_error_code ret;
krb5_data pub;
size_t size;
krb5_data_zero(other);
memset(&otherinfo, 0, sizeof(otherinfo));
memset(&pubinfo, 0, sizeof(pubinfo));
pubinfo.enctype = enctype;
pubinfo.as_REQ = *as_req;
pubinfo.pk_as_rep = *pk_as_rep;
pubinfo.ticket = *ticket;
ASN1_MALLOC_ENCODE(PkinitSuppPubInfo, pub.data, pub.length,
&pubinfo, &size, ret);
if (ret) {
krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
return ret;
}
if (pub.length != size)
krb5_abortx(context, "asn1 compiler internal error");
ret = encode_uvinfo(context, client, &otherinfo.partyUInfo);
if (ret) {
free(pub.data);
return ret;
}
ret = encode_uvinfo(context, server, &otherinfo.partyVInfo);
if (ret) {
free(otherinfo.partyUInfo.data);
free(pub.data);
return ret;
}
otherinfo.algorithmID = *ai;
otherinfo.suppPubInfo = &pub;
ASN1_MALLOC_ENCODE(PkinitSP80056AOtherInfo, other->data, other->length,
&otherinfo, &size, ret);
free(otherinfo.partyUInfo.data);
free(otherinfo.partyVInfo.data);
free(pub.data);
if (ret) {
krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
return ret;
}
if (other->length != size)
krb5_abortx(context, "asn1 compiler internal error");
return 0;
}
krb5_error_code
_krb5_pk_kdf(krb5_context context,
const struct AlgorithmIdentifier *ai,
const void *dhdata,
size_t dhsize,
krb5_const_principal client,
krb5_const_principal server,
krb5_enctype enctype,
const krb5_data *as_req,
const krb5_data *pk_as_rep,
const Ticket *ticket,
krb5_keyblock *key)
{
struct encryption_type *et;
krb5_error_code ret;
krb5_data other;
size_t keylen, offset;
uint32_t counter;
unsigned char *keydata;
unsigned char shaoutput[SHA_DIGEST_LENGTH];
EVP_MD_CTX *m;
if (der_heim_oid_cmp(&asn1_oid_id_pkinit_kdf_ah_sha1, &ai->algorithm) != 0) {
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
N_("KDF not supported", ""));
return KRB5_PROG_ETYPE_NOSUPP;
}
if (ai->parameters != NULL &&
(ai->parameters->length != 2 ||
memcmp(ai->parameters->data, "\x05\x00", 2) != 0))
{
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
N_("kdf params not NULL or the NULL-type",
""));
return KRB5_PROG_ETYPE_NOSUPP;
}
et = _find_enctype(enctype);
if(et == NULL) {
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
enctype);
return KRB5_PROG_ETYPE_NOSUPP;
}
keylen = (et->keytype->bits + 7) / 8;
keydata = malloc(keylen);
if (keydata == NULL) {
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
ret = encode_otherinfo(context, ai, client, server,
enctype, as_req, pk_as_rep, ticket, &other);
if (ret) {
free(keydata);
return ret;
}
m = EVP_MD_CTX_create();
if (m == NULL) {
free(keydata);
free(other.data);
krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
return ENOMEM;
}
offset = 0;
counter = 1;
do {
unsigned char cdata[4];
EVP_DigestInit_ex(m, EVP_sha1(), NULL);
_krb5_put_int(cdata, counter, 4);
EVP_DigestUpdate(m, cdata, 4);
EVP_DigestUpdate(m, dhdata, dhsize);
EVP_DigestUpdate(m, other.data, other.length);
EVP_DigestFinal_ex(m, shaoutput, NULL);
memcpy((unsigned char *)keydata + offset,
shaoutput,
min(keylen - offset, sizeof(shaoutput)));
offset += sizeof(shaoutput);
counter++;
} while(offset < keylen);
memset(shaoutput, 0, sizeof(shaoutput));
EVP_MD_CTX_destroy(m);
free(other.data);
ret = krb5_random_to_key(context, enctype, keydata, keylen, key);
memset(keydata, 0, sizeof(keylen));
free(keydata);
return ret;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_crypto_prf_length(krb5_context context,
krb5_enctype type,
size_t *length)
{
struct encryption_type *et = _find_enctype(type);
if(et == NULL || et->prf_length == 0) {
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
N_("encryption type %d not supported", ""),
type);
return KRB5_PROG_ETYPE_NOSUPP;
}
*length = et->prf_length;
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_crypto_prf(krb5_context context,
const krb5_crypto crypto,
const krb5_data *input,
krb5_data *output)
{
struct encryption_type *et = crypto->et;
krb5_data_zero(output);
if(et->prf == NULL) {
krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
"kerberos prf for %s not supported",
et->name);
return KRB5_PROG_ETYPE_NOSUPP;
}
return (*et->prf)(context, crypto, input, output);
}
static krb5_error_code
krb5_crypto_prfplus(krb5_context context,
const krb5_crypto crypto,
const krb5_data *input,
size_t length,
krb5_data *output)
{
krb5_error_code ret;
krb5_data input2;
unsigned char i = 1;
unsigned char *p;
krb5_data_zero(&input2);
krb5_data_zero(output);
krb5_clear_error_message(context);
ret = krb5_data_alloc(output, length);
if (ret) goto out;
ret = krb5_data_alloc(&input2, input->length + 1);
if (ret) goto out;
krb5_clear_error_message(context);
memcpy(((unsigned char *)input2.data) + 1, input->data, input->length);
p = output->data;
while (length) {
krb5_data block;
((unsigned char *)input2.data)[0] = i++;
ret = krb5_crypto_prf(context, crypto, &input2, &block);
if (ret)
goto out;
if (block.length < length) {
memcpy(p, block.data, block.length);
length -= block.length;
} else {
memcpy(p, block.data, length);
length = 0;
}
p += block.length;
krb5_data_free(&block);
}
out:
krb5_data_free(&input2);
if (ret)
krb5_data_free(output);
return 0;
}
/**
* The FX-CF2 key derivation function, used in FAST and preauth framework.
*
* @param context Kerberos 5 context
* @param crypto1 first key to combine
* @param crypto2 second key to combine
* @param pepper1 factor to combine with first key to garante uniqueness
* @param pepper2 factor to combine with second key to garante uniqueness
* @param enctype the encryption type of the resulting key
* @param res allocated key, free with krb5_free_keyblock_contents()
*
* @return Return an error code or 0.
*
* @ingroup krb5_crypto
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_crypto_fx_cf2(krb5_context context,
const krb5_crypto crypto1,
const krb5_crypto crypto2,
krb5_data *pepper1,
krb5_data *pepper2,
krb5_enctype enctype,
krb5_keyblock *res)
{
krb5_error_code ret;
krb5_data os1, os2;
size_t i, keysize;
memset(res, 0, sizeof(*res));
ret = krb5_enctype_keysize(context, enctype, &keysize);
if (ret)
return ret;
ret = krb5_data_alloc(&res->keyvalue, keysize);
if (ret)
goto out;
ret = krb5_crypto_prfplus(context, crypto1, pepper1, keysize, &os1);
if (ret)
goto out;
ret = krb5_crypto_prfplus(context, crypto2, pepper2, keysize, &os2);
if (ret)
goto out;
res->keytype = enctype;
{
unsigned char *p1 = os1.data, *p2 = os2.data, *p3 = res->keyvalue.data;
for (i = 0; i < keysize; i++)
p3[i] = p1[i] ^ p2[i];
}
out:
if (ret)
krb5_data_free(&res->keyvalue);
krb5_data_free(&os1);
krb5_data_free(&os2);
return ret;
}
#ifndef HEIMDAL_SMALLER
/**
* Deprecated: keytypes doesn't exists, they are really enctypes.
*
* @ingroup krb5_deprecated
*/
KRB5_DEPRECATED
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_keytype_to_enctypes (krb5_context context,
krb5_keytype keytype,
unsigned *len,
krb5_enctype **val)
{
int i;
unsigned n = 0;
krb5_enctype *ret;
for (i = num_etypes - 1; i >= 0; --i) {
if (etypes[i]->keytype->type == keytype
&& !(etypes[i]->flags & F_PSEUDO)
&& krb5_enctype_valid(context, etypes[i]->type) == 0)
++n;
}
if (n == 0) {
krb5_set_error_message(context, KRB5_PROG_KEYTYPE_NOSUPP,
"Keytype have no mapping");
return KRB5_PROG_KEYTYPE_NOSUPP;
}
ret = malloc(n * sizeof(*ret));
if (ret == NULL && n != 0) {
krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
return ENOMEM;
}
n = 0;
for (i = num_etypes - 1; i >= 0; --i) {
if (etypes[i]->keytype->type == keytype
&& !(etypes[i]->flags & F_PSEUDO)
&& krb5_enctype_valid(context, etypes[i]->type) == 0)
ret[n++] = etypes[i]->type;
}
*len = n;
*val = ret;
return 0;
}
/**
* Deprecated: keytypes doesn't exists, they are really enctypes.
*
* @ingroup krb5_deprecated
*/
/* if two enctypes have compatible keys */
KRB5_DEPRECATED
KRB5_LIB_FUNCTION krb5_boolean KRB5_LIB_CALL
krb5_enctypes_compatible_keys(krb5_context context,
krb5_enctype etype1,
krb5_enctype etype2)
{
struct encryption_type *e1 = _find_enctype(etype1);
struct encryption_type *e2 = _find_enctype(etype2);
return e1 != NULL && e2 != NULL && e1->keytype == e2->keytype;
}
#endif /* HEIMDAL_SMALLER */
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