/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* lib/krad/attr.c - RADIUS attribute functions for libkrad */
/*
* Copyright 2013 Red Hat, Inc. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER
* 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.
*/
#include <k5-int.h>
#include "internal.h"
#include <string.h>
/* RFC 2865 */
#define BLOCKSIZE 16
typedef krb5_error_code
(*attribute_transform_fn)(krb5_context ctx, const char *secret,
const unsigned char *auth, const krb5_data *in,
unsigned char outbuf[MAX_ATTRSIZE], size_t *outlen,
krb5_boolean *is_fips);
typedef struct {
const char *name;
unsigned char minval;
unsigned char maxval;
attribute_transform_fn encode;
attribute_transform_fn decode;
} attribute_record;
static krb5_error_code
user_password_encode(krb5_context ctx, const char *secret,
const unsigned char *auth, const krb5_data *in,
unsigned char outbuf[MAX_ATTRSIZE], size_t *outlen,
krb5_boolean *is_fips);
static krb5_error_code
user_password_decode(krb5_context ctx, const char *secret,
const unsigned char *auth, const krb5_data *in,
unsigned char outbuf[MAX_ATTRSIZE], size_t *outlen,
krb5_boolean *ignored);
static const attribute_record attributes[UCHAR_MAX] = {
{"User-Name", 1, MAX_ATTRSIZE, NULL, NULL},
{"User-Password", 1, 128, user_password_encode, user_password_decode},
{"CHAP-Password", 17, 17, NULL, NULL},
{"NAS-IP-Address", 4, 4, NULL, NULL},
{"NAS-Port", 4, 4, NULL, NULL},
{"Service-Type", 4, 4, NULL, NULL},
{"Framed-Protocol", 4, 4, NULL, NULL},
{"Framed-IP-Address", 4, 4, NULL, NULL},
{"Framed-IP-Netmask", 4, 4, NULL, NULL},
{"Framed-Routing", 4, 4, NULL, NULL},
{"Filter-Id", 1, MAX_ATTRSIZE, NULL, NULL},
{"Framed-MTU", 4, 4, NULL, NULL},
{"Framed-Compression", 4, 4, NULL, NULL},
{"Login-IP-Host", 4, 4, NULL, NULL},
{"Login-Service", 4, 4, NULL, NULL},
{"Login-TCP-Port", 4, 4, NULL, NULL},
{NULL, 0, 0, NULL, NULL}, /* Unassigned */
{"Reply-Message", 1, MAX_ATTRSIZE, NULL, NULL},
{"Callback-Number", 1, MAX_ATTRSIZE, NULL, NULL},
{"Callback-Id", 1, MAX_ATTRSIZE, NULL, NULL},
{NULL, 0, 0, NULL, NULL}, /* Unassigned */
{"Framed-Route", 1, MAX_ATTRSIZE, NULL, NULL},
{"Framed-IPX-Network", 4, 4, NULL, NULL},
{"State", 1, MAX_ATTRSIZE, NULL, NULL},
{"Class", 1, MAX_ATTRSIZE, NULL, NULL},
{"Vendor-Specific", 5, MAX_ATTRSIZE, NULL, NULL},
{"Session-Timeout", 4, 4, NULL, NULL},
{"Idle-Timeout", 4, 4, NULL, NULL},
{"Termination-Action", 4, 4, NULL, NULL},
{"Called-Station-Id", 1, MAX_ATTRSIZE, NULL, NULL},
{"Calling-Station-Id", 1, MAX_ATTRSIZE, NULL, NULL},
{"NAS-Identifier", 1, MAX_ATTRSIZE, NULL, NULL},
{"Proxy-State", 1, MAX_ATTRSIZE, NULL, NULL},
{"Login-LAT-Service", 1, MAX_ATTRSIZE, NULL, NULL},
{"Login-LAT-Node", 1, MAX_ATTRSIZE, NULL, NULL},
{"Login-LAT-Group", 32, 32, NULL, NULL},
{"Framed-AppleTalk-Link", 4, 4, NULL, NULL},
{"Framed-AppleTalk-Network", 4, 4, NULL, NULL},
{"Framed-AppleTalk-Zone", 1, MAX_ATTRSIZE, NULL, NULL},
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{NULL, 0, 0, NULL, NULL}, /* Reserved for accounting */
{"CHAP-Challenge", 5, MAX_ATTRSIZE, NULL, NULL},
{"NAS-Port-Type", 4, 4, NULL, NULL},
{"Port-Limit", 4, 4, NULL, NULL},
{"Login-LAT-Port", 1, MAX_ATTRSIZE, NULL, NULL},
};
/* Encode User-Password attribute. */
static krb5_error_code
user_password_encode(krb5_context ctx, const char *secret,
const unsigned char *auth, const krb5_data *in,
unsigned char outbuf[MAX_ATTRSIZE], size_t *outlen,
krb5_boolean *is_fips)
{
const unsigned char *indx;
krb5_error_code retval;
unsigned int seclen;
krb5_checksum sum;
size_t blck, len, i;
krb5_data tmp;
/* Copy the input buffer to the (zero-padded) output buffer. */
len = (in->length + BLOCKSIZE - 1) / BLOCKSIZE * BLOCKSIZE;
if (len > MAX_ATTRSIZE)
return ENOBUFS;
memset(outbuf, 0, len);
memcpy(outbuf, in->data, in->length);
/* Create our temporary space for processing each block. */
seclen = strlen(secret);
retval = alloc_data(&tmp, seclen + BLOCKSIZE);
if (retval != 0)
return retval;
memcpy(tmp.data, secret, seclen);
for (blck = 0, indx = auth; blck * BLOCKSIZE < len; blck++) {
memcpy(tmp.data + seclen, indx, BLOCKSIZE);
if (kr_use_fips(ctx)) {
/* Skip encryption here. Taint so that we won't pass it out of
* the machine by accident. */
*is_fips = TRUE;
sum.contents = calloc(1, BLOCKSIZE);
} else {
retval = krb5_c_make_checksum(ctx, CKSUMTYPE_RSA_MD5, NULL, 0, &tmp,
&sum);
}
if (retval != 0) {
zap(tmp.data, tmp.length);
zap(outbuf, len);
krb5_free_data_contents(ctx, &tmp);
return retval;
}
for (i = 0; i < BLOCKSIZE; i++)
outbuf[blck * BLOCKSIZE + i] ^= sum.contents[i];
krb5_free_checksum_contents(ctx, &sum);
indx = &outbuf[blck * BLOCKSIZE];
}
zap(tmp.data, tmp.length);
krb5_free_data_contents(ctx, &tmp);
*outlen = len;
return 0;
}
/* Decode User-Password attribute. */
static krb5_error_code
user_password_decode(krb5_context ctx, const char *secret,
const unsigned char *auth, const krb5_data *in,
unsigned char outbuf[MAX_ATTRSIZE], size_t *outlen,
krb5_boolean *is_fips)
{
const unsigned char *indx;
krb5_error_code retval;
unsigned int seclen;
krb5_checksum sum;
ssize_t blck, i;
krb5_data tmp;
if (in->length % BLOCKSIZE != 0)
return EINVAL;
if (in->length > MAX_ATTRSIZE)
return ENOBUFS;
/* Create our temporary space for processing each block. */
seclen = strlen(secret);
retval = alloc_data(&tmp, seclen + BLOCKSIZE);
if (retval != 0)
return retval;
memcpy(tmp.data, secret, seclen);
for (blck = 0, indx = auth; blck * BLOCKSIZE < in->length; blck++) {
memcpy(tmp.data + seclen, indx, BLOCKSIZE);
if (kr_use_fips(ctx)) {
/* Skip encryption here. Taint so that we won't pass it out of
* the machine by accident. */
*is_fips = TRUE;
sum.contents = calloc(1, BLOCKSIZE);
} else {
retval = krb5_c_make_checksum(ctx, CKSUMTYPE_RSA_MD5, NULL, 0,
&tmp, &sum);
}
if (retval != 0) {
zap(tmp.data, tmp.length);
zap(outbuf, in->length);
krb5_free_data_contents(ctx, &tmp);
return retval;
}
for (i = 0; i < BLOCKSIZE; i++) {
outbuf[blck * BLOCKSIZE + i] = in->data[blck * BLOCKSIZE + i] ^
sum.contents[i];
}
krb5_free_checksum_contents(ctx, &sum);
indx = (const unsigned char *)&in->data[blck * BLOCKSIZE];
}
/* Strip off trailing NULL bytes. */
*outlen = in->length;
while (*outlen > 0 && outbuf[*outlen - 1] == '\0')
(*outlen)--;
krb5_free_data_contents(ctx, &tmp);
return 0;
}
krb5_error_code
kr_attr_valid(krad_attr type, const krb5_data *data)
{
const attribute_record *ar;
if (type == 0)
return EINVAL;
ar = &attributes[type - 1];
return (data->length >= ar->minval && data->length <= ar->maxval) ? 0 :
EMSGSIZE;
}
krb5_error_code
kr_attr_encode(krb5_context ctx, const char *secret,
const unsigned char *auth, krad_attr type,
const krb5_data *in, unsigned char outbuf[MAX_ATTRSIZE],
size_t *outlen, krb5_boolean *is_fips)
{
krb5_error_code retval;
retval = kr_attr_valid(type, in);
if (retval != 0)
return retval;
if (attributes[type - 1].encode == NULL) {
if (in->length > MAX_ATTRSIZE)
return ENOBUFS;
*outlen = in->length;
memcpy(outbuf, in->data, in->length);
return 0;
}
return attributes[type - 1].encode(ctx, secret, auth, in, outbuf, outlen,
is_fips);
}
krb5_error_code
kr_attr_decode(krb5_context ctx, const char *secret, const unsigned char *auth,
krad_attr type, const krb5_data *in,
unsigned char outbuf[MAX_ATTRSIZE], size_t *outlen)
{
krb5_error_code retval;
krb5_boolean ignored;
retval = kr_attr_valid(type, in);
if (retval != 0)
return retval;
if (attributes[type - 1].encode == NULL) {
if (in->length > MAX_ATTRSIZE)
return ENOBUFS;
*outlen = in->length;
memcpy(outbuf, in->data, in->length);
return 0;
}
return attributes[type - 1].decode(ctx, secret, auth, in, outbuf, outlen,
&ignored);
}
krad_attr
krad_attr_name2num(const char *name)
{
unsigned char i;
for (i = 0; i < UCHAR_MAX; i++) {
if (attributes[i].name == NULL)
continue;
if (strcmp(attributes[i].name, name) == 0)
return i + 1;
}
return 0;
}
const char *
krad_attr_num2name(krad_attr type)
{
if (type == 0)
return NULL;
return attributes[type - 1].name;
}