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|
/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* lib/krb5/krb/pac.c */
/*
* Copyright 2008 by the Massachusetts Institute of Technology.
* All Rights Reserved.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*/
#include "k5-int.h"
#include "authdata.h"
/* draft-brezak-win2k-krb-authz-00 */
/*
* Add a buffer to the provided PAC and update header.
*/
krb5_error_code
k5_pac_add_buffer(krb5_context context,
krb5_pac pac,
krb5_ui_4 type,
const krb5_data *data,
krb5_boolean zerofill,
krb5_data *out_data)
{
PACTYPE *header;
size_t header_len, i, pad = 0;
char *pac_data;
assert((data->data == NULL) == zerofill);
/* Check there isn't already a buffer of this type */
if (k5_pac_locate_buffer(context, pac, type, NULL) == 0) {
return EEXIST;
}
header = (PACTYPE *)realloc(pac->pac,
sizeof(PACTYPE) +
(pac->pac->cBuffers * sizeof(PAC_INFO_BUFFER)));
if (header == NULL) {
return ENOMEM;
}
pac->pac = header;
header_len = PACTYPE_LENGTH + (pac->pac->cBuffers * PAC_INFO_BUFFER_LENGTH);
if (data->length % PAC_ALIGNMENT)
pad = PAC_ALIGNMENT - (data->length % PAC_ALIGNMENT);
pac_data = realloc(pac->data.data,
pac->data.length + PAC_INFO_BUFFER_LENGTH + data->length + pad);
if (pac_data == NULL) {
return ENOMEM;
}
pac->data.data = pac_data;
/* Update offsets of existing buffers */
for (i = 0; i < pac->pac->cBuffers; i++)
pac->pac->Buffers[i].Offset += PAC_INFO_BUFFER_LENGTH;
/* Make room for new PAC_INFO_BUFFER */
memmove(pac->data.data + header_len + PAC_INFO_BUFFER_LENGTH,
pac->data.data + header_len,
pac->data.length - header_len);
memset(pac->data.data + header_len, 0, PAC_INFO_BUFFER_LENGTH);
/* Initialise new PAC_INFO_BUFFER */
pac->pac->Buffers[i].ulType = type;
pac->pac->Buffers[i].cbBufferSize = data->length;
pac->pac->Buffers[i].Offset = pac->data.length + PAC_INFO_BUFFER_LENGTH;
assert((pac->pac->Buffers[i].Offset % PAC_ALIGNMENT) == 0);
/* Copy in new PAC data and zero padding bytes */
if (zerofill)
memset(pac->data.data + pac->pac->Buffers[i].Offset, 0, data->length);
else
memcpy(pac->data.data + pac->pac->Buffers[i].Offset, data->data, data->length);
memset(pac->data.data + pac->pac->Buffers[i].Offset + data->length, 0, pad);
pac->pac->cBuffers++;
pac->data.length += PAC_INFO_BUFFER_LENGTH + data->length + pad;
if (out_data != NULL) {
out_data->data = pac->data.data + pac->pac->Buffers[i].Offset;
out_data->length = data->length;
}
pac->verified = FALSE;
return 0;
}
krb5_error_code KRB5_CALLCONV
krb5_pac_add_buffer(krb5_context context,
krb5_pac pac,
krb5_ui_4 type,
const krb5_data *data)
{
return k5_pac_add_buffer(context, pac, type, data, FALSE, NULL);
}
/*
* Free a PAC
*/
void KRB5_CALLCONV
krb5_pac_free(krb5_context context,
krb5_pac pac)
{
if (pac != NULL) {
zapfree(pac->data.data, pac->data.length);
free(pac->pac);
zapfree(pac, sizeof(*pac));
}
}
krb5_error_code
k5_pac_locate_buffer(krb5_context context,
const krb5_pac pac,
krb5_ui_4 type,
krb5_data *data)
{
PAC_INFO_BUFFER *buffer = NULL;
size_t i;
if (pac == NULL)
return EINVAL;
for (i = 0; i < pac->pac->cBuffers; i++) {
if (pac->pac->Buffers[i].ulType == type) {
if (buffer == NULL)
buffer = &pac->pac->Buffers[i];
else
return EINVAL;
}
}
if (buffer == NULL)
return ENOENT;
assert(buffer->Offset + buffer->cbBufferSize <= pac->data.length);
if (data != NULL) {
data->length = buffer->cbBufferSize;
data->data = pac->data.data + buffer->Offset;
}
return 0;
}
/*
* Find a buffer and copy data into output
*/
krb5_error_code KRB5_CALLCONV
krb5_pac_get_buffer(krb5_context context,
krb5_pac pac,
krb5_ui_4 type,
krb5_data *data)
{
krb5_data d;
krb5_error_code ret;
ret = k5_pac_locate_buffer(context, pac, type, &d);
if (ret != 0)
return ret;
data->data = k5memdup(d.data, d.length, &ret);
if (data->data == NULL)
return ret;
data->length = d.length;
return 0;
}
/*
* Return an array of the types of data in the PAC
*/
krb5_error_code KRB5_CALLCONV
krb5_pac_get_types(krb5_context context,
krb5_pac pac,
size_t *len,
krb5_ui_4 **types)
{
size_t i;
*types = (krb5_ui_4 *)malloc(pac->pac->cBuffers * sizeof(krb5_ui_4));
if (*types == NULL)
return ENOMEM;
*len = pac->pac->cBuffers;
for (i = 0; i < pac->pac->cBuffers; i++)
(*types)[i] = pac->pac->Buffers[i].ulType;
return 0;
}
/*
* Initialize PAC
*/
krb5_error_code KRB5_CALLCONV
krb5_pac_init(krb5_context context,
krb5_pac *ppac)
{
krb5_pac pac;
pac = (krb5_pac)malloc(sizeof(*pac));
if (pac == NULL)
return ENOMEM;
pac->pac = (PACTYPE *)malloc(sizeof(PACTYPE));
if (pac->pac == NULL) {
free(pac);
return ENOMEM;
}
pac->pac->cBuffers = 0;
pac->pac->Version = 0;
pac->data.length = PACTYPE_LENGTH;
pac->data.data = calloc(1, pac->data.length);
if (pac->data.data == NULL) {
krb5_pac_free(context, pac);
return ENOMEM;
}
pac->verified = FALSE;
*ppac = pac;
return 0;
}
static krb5_error_code
k5_pac_copy(krb5_context context,
krb5_pac src,
krb5_pac *dst)
{
size_t header_len;
krb5_ui_4 cbuffers;
krb5_error_code code;
krb5_pac pac;
cbuffers = src->pac->cBuffers;
if (cbuffers != 0)
cbuffers--;
header_len = sizeof(PACTYPE) + cbuffers * sizeof(PAC_INFO_BUFFER);
pac = (krb5_pac)malloc(sizeof(*pac));
if (pac == NULL)
return ENOMEM;
pac->pac = k5memdup(src->pac, header_len, &code);
if (pac->pac == NULL) {
free(pac);
return code;
}
code = krb5int_copy_data_contents(context, &src->data, &pac->data);
if (code != 0) {
free(pac->pac);
free(pac);
return ENOMEM;
}
pac->verified = src->verified;
*dst = pac;
return 0;
}
/*
* Parse the supplied data into the PAC allocated by this function
*/
krb5_error_code KRB5_CALLCONV
krb5_pac_parse(krb5_context context,
const void *ptr,
size_t len,
krb5_pac *ppac)
{
krb5_error_code ret;
size_t i;
const unsigned char *p = (const unsigned char *)ptr;
krb5_pac pac;
size_t header_len;
krb5_ui_4 cbuffers, version;
*ppac = NULL;
if (len < PACTYPE_LENGTH)
return ERANGE;
cbuffers = load_32_le(p);
p += 4;
version = load_32_le(p);
p += 4;
if (version != 0)
return EINVAL;
header_len = PACTYPE_LENGTH + (cbuffers * PAC_INFO_BUFFER_LENGTH);
if (len < header_len)
return ERANGE;
ret = krb5_pac_init(context, &pac);
if (ret != 0)
return ret;
pac->pac = (PACTYPE *)realloc(pac->pac,
sizeof(PACTYPE) + ((cbuffers - 1) * sizeof(PAC_INFO_BUFFER)));
if (pac->pac == NULL) {
krb5_pac_free(context, pac);
return ENOMEM;
}
pac->pac->cBuffers = cbuffers;
pac->pac->Version = version;
for (i = 0; i < pac->pac->cBuffers; i++) {
PAC_INFO_BUFFER *buffer = &pac->pac->Buffers[i];
buffer->ulType = load_32_le(p);
p += 4;
buffer->cbBufferSize = load_32_le(p);
p += 4;
buffer->Offset = load_64_le(p);
p += 8;
if (buffer->Offset % PAC_ALIGNMENT) {
krb5_pac_free(context, pac);
return EINVAL;
}
if (buffer->Offset < header_len ||
buffer->Offset + buffer->cbBufferSize > len) {
krb5_pac_free(context, pac);
return ERANGE;
}
}
pac->data.data = realloc(pac->data.data, len);
if (pac->data.data == NULL) {
krb5_pac_free(context, pac);
return ENOMEM;
}
memcpy(pac->data.data, ptr, len);
pac->data.length = len;
*ppac = pac;
return 0;
}
static krb5_error_code
k5_time_to_seconds_since_1970(int64_t ntTime, krb5_timestamp *elapsedSeconds)
{
uint64_t abstime;
ntTime /= 10000000;
abstime = ntTime > 0 ? ntTime - NT_TIME_EPOCH : -ntTime;
if (abstime > KRB5_INT32_MAX)
return ERANGE;
*elapsedSeconds = abstime;
return 0;
}
krb5_error_code
k5_seconds_since_1970_to_time(krb5_timestamp elapsedSeconds, uint64_t *ntTime)
{
*ntTime = elapsedSeconds;
if (elapsedSeconds > 0)
*ntTime += NT_TIME_EPOCH;
*ntTime *= 10000000;
return 0;
}
krb5_error_code
k5_pac_validate_client(krb5_context context,
const krb5_pac pac,
krb5_timestamp authtime,
krb5_const_principal principal)
{
krb5_error_code ret;
krb5_data client_info;
char *pac_princname;
unsigned char *p;
krb5_timestamp pac_authtime;
krb5_ui_2 pac_princname_length;
int64_t pac_nt_authtime;
krb5_principal pac_principal;
ret = k5_pac_locate_buffer(context, pac, KRB5_PAC_CLIENT_INFO,
&client_info);
if (ret != 0)
return ret;
if (client_info.length < PAC_CLIENT_INFO_LENGTH)
return ERANGE;
p = (unsigned char *)client_info.data;
pac_nt_authtime = load_64_le(p);
p += 8;
pac_princname_length = load_16_le(p);
p += 2;
ret = k5_time_to_seconds_since_1970(pac_nt_authtime, &pac_authtime);
if (ret != 0)
return ret;
if (client_info.length < PAC_CLIENT_INFO_LENGTH + pac_princname_length ||
pac_princname_length % 2)
return ERANGE;
ret = krb5int_ucs2lecs_to_utf8s(p, (size_t)pac_princname_length / 2,
&pac_princname, NULL);
if (ret != 0)
return ret;
ret = krb5_parse_name_flags(context, pac_princname,
KRB5_PRINCIPAL_PARSE_NO_REALM, &pac_principal);
if (ret != 0) {
free(pac_princname);
return ret;
}
free(pac_princname);
if (pac_authtime != authtime ||
!krb5_principal_compare_flags(context,
pac_principal,
principal,
KRB5_PRINCIPAL_COMPARE_IGNORE_REALM))
ret = KRB5KRB_AP_WRONG_PRINC;
krb5_free_principal(context, pac_principal);
return ret;
}
static krb5_error_code
k5_pac_zero_signature(krb5_context context,
const krb5_pac pac,
krb5_ui_4 type,
krb5_data *data)
{
PAC_INFO_BUFFER *buffer = NULL;
size_t i;
assert(type == KRB5_PAC_SERVER_CHECKSUM ||
type == KRB5_PAC_PRIVSVR_CHECKSUM);
assert(data->length >= pac->data.length);
for (i = 0; i < pac->pac->cBuffers; i++) {
if (pac->pac->Buffers[i].ulType == type) {
buffer = &pac->pac->Buffers[i];
break;
}
}
if (buffer == NULL)
return ENOENT;
if (buffer->Offset + buffer->cbBufferSize > pac->data.length)
return ERANGE;
if (buffer->cbBufferSize < PAC_SIGNATURE_DATA_LENGTH)
return KRB5_BAD_MSIZE;
/* Zero out the data portion of the checksum only */
memset(data->data + buffer->Offset + PAC_SIGNATURE_DATA_LENGTH,
0,
buffer->cbBufferSize - PAC_SIGNATURE_DATA_LENGTH);
return 0;
}
static krb5_error_code
k5_pac_verify_server_checksum(krb5_context context,
const krb5_pac pac,
const krb5_keyblock *server)
{
krb5_error_code ret;
krb5_data pac_data; /* PAC with zeroed checksums */
krb5_checksum checksum;
krb5_data checksum_data;
krb5_boolean valid;
krb5_octet *p;
ret = k5_pac_locate_buffer(context, pac, KRB5_PAC_SERVER_CHECKSUM,
&checksum_data);
if (ret != 0)
return ret;
if (checksum_data.length < PAC_SIGNATURE_DATA_LENGTH)
return KRB5_BAD_MSIZE;
p = (krb5_octet *)checksum_data.data;
checksum.checksum_type = load_32_le(p);
checksum.length = checksum_data.length - PAC_SIGNATURE_DATA_LENGTH;
checksum.contents = p + PAC_SIGNATURE_DATA_LENGTH;
if (!krb5_c_is_keyed_cksum(checksum.checksum_type))
return KRB5KRB_AP_ERR_INAPP_CKSUM;
pac_data.length = pac->data.length;
pac_data.data = k5memdup(pac->data.data, pac->data.length, &ret);
if (pac_data.data == NULL)
return ret;
/* Zero out both checksum buffers */
ret = k5_pac_zero_signature(context, pac, KRB5_PAC_SERVER_CHECKSUM,
&pac_data);
if (ret != 0) {
free(pac_data.data);
return ret;
}
ret = k5_pac_zero_signature(context, pac, KRB5_PAC_PRIVSVR_CHECKSUM,
&pac_data);
if (ret != 0) {
free(pac_data.data);
return ret;
}
ret = krb5_c_verify_checksum(context, server,
KRB5_KEYUSAGE_APP_DATA_CKSUM,
&pac_data, &checksum, &valid);
free(pac_data.data);
if (ret != 0) {
return ret;
}
if (valid == FALSE)
ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
return ret;
}
static krb5_error_code
k5_pac_verify_kdc_checksum(krb5_context context,
const krb5_pac pac,
const krb5_keyblock *privsvr)
{
krb5_error_code ret;
krb5_data server_checksum, privsvr_checksum;
krb5_checksum checksum;
krb5_boolean valid;
krb5_octet *p;
ret = k5_pac_locate_buffer(context, pac, KRB5_PAC_PRIVSVR_CHECKSUM,
&privsvr_checksum);
if (ret != 0)
return ret;
if (privsvr_checksum.length < PAC_SIGNATURE_DATA_LENGTH)
return KRB5_BAD_MSIZE;
ret = k5_pac_locate_buffer(context, pac, KRB5_PAC_SERVER_CHECKSUM,
&server_checksum);
if (ret != 0)
return ret;
if (server_checksum.length < PAC_SIGNATURE_DATA_LENGTH)
return KRB5_BAD_MSIZE;
p = (krb5_octet *)privsvr_checksum.data;
checksum.checksum_type = load_32_le(p);
checksum.length = privsvr_checksum.length - PAC_SIGNATURE_DATA_LENGTH;
checksum.contents = p + PAC_SIGNATURE_DATA_LENGTH;
if (!krb5_c_is_keyed_cksum(checksum.checksum_type))
return KRB5KRB_AP_ERR_INAPP_CKSUM;
server_checksum.data += PAC_SIGNATURE_DATA_LENGTH;
server_checksum.length -= PAC_SIGNATURE_DATA_LENGTH;
ret = krb5_c_verify_checksum(context, privsvr,
KRB5_KEYUSAGE_APP_DATA_CKSUM,
&server_checksum, &checksum, &valid);
if (ret != 0)
return ret;
if (valid == FALSE)
ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
return ret;
}
krb5_error_code KRB5_CALLCONV
krb5_pac_verify(krb5_context context,
const krb5_pac pac,
krb5_timestamp authtime,
krb5_const_principal principal,
const krb5_keyblock *server,
const krb5_keyblock *privsvr)
{
krb5_error_code ret;
if (server != NULL) {
ret = k5_pac_verify_server_checksum(context, pac, server);
if (ret != 0)
return ret;
}
if (privsvr != NULL) {
ret = k5_pac_verify_kdc_checksum(context, pac, privsvr);
if (ret != 0)
return ret;
}
if (principal != NULL) {
ret = k5_pac_validate_client(context, pac, authtime, principal);
if (ret != 0)
return ret;
}
pac->verified = TRUE;
return 0;
}
/*
* PAC auth data attribute backend
*/
struct mspac_context {
krb5_pac pac;
};
static krb5_error_code
mspac_init(krb5_context kcontext, void **plugin_context)
{
*plugin_context = NULL;
return 0;
}
static void
mspac_flags(krb5_context kcontext,
void *plugin_context,
krb5_authdatatype ad_type,
krb5_flags *flags)
{
*flags = AD_USAGE_TGS_REQ;
}
static void
mspac_fini(krb5_context kcontext, void *plugin_context)
{
return;
}
static krb5_error_code
mspac_request_init(krb5_context kcontext,
krb5_authdata_context context,
void *plugin_context,
void **request_context)
{
struct mspac_context *pacctx;
pacctx = (struct mspac_context *)malloc(sizeof(*pacctx));
if (pacctx == NULL)
return ENOMEM;
pacctx->pac = NULL;
*request_context = pacctx;
return 0;
}
static krb5_error_code
mspac_import_authdata(krb5_context kcontext,
krb5_authdata_context context,
void *plugin_context,
void *request_context,
krb5_authdata **authdata,
krb5_boolean kdc_issued,
krb5_const_principal kdc_issuer)
{
krb5_error_code code;
struct mspac_context *pacctx = (struct mspac_context *)request_context;
if (kdc_issued)
return EINVAL;
if (pacctx->pac != NULL) {
krb5_pac_free(kcontext, pacctx->pac);
pacctx->pac = NULL;
}
assert(authdata[0] != NULL);
assert((authdata[0]->ad_type & AD_TYPE_FIELD_TYPE_MASK) ==
KRB5_AUTHDATA_WIN2K_PAC);
code = krb5_pac_parse(kcontext, authdata[0]->contents,
authdata[0]->length, &pacctx->pac);
return code;
}
static krb5_error_code
mspac_export_authdata(krb5_context kcontext,
krb5_authdata_context context,
void *plugin_context,
void *request_context,
krb5_flags usage,
krb5_authdata ***out_authdata)
{
struct mspac_context *pacctx = (struct mspac_context *)request_context;
krb5_error_code code;
krb5_authdata **authdata;
krb5_data data;
if (pacctx->pac == NULL)
return 0;
authdata = calloc(2, sizeof(krb5_authdata *));
if (authdata == NULL)
return ENOMEM;
authdata[0] = calloc(1, sizeof(krb5_authdata));
if (authdata[0] == NULL) {
free(authdata);
return ENOMEM;
}
authdata[1] = NULL;
code = krb5int_copy_data_contents(kcontext, &pacctx->pac->data, &data);
if (code != 0) {
krb5_free_authdata(kcontext, authdata);
return code;
}
authdata[0]->magic = KV5M_AUTHDATA;
authdata[0]->ad_type = KRB5_AUTHDATA_WIN2K_PAC;
authdata[0]->length = data.length;
authdata[0]->contents = (krb5_octet *)data.data;
authdata[1] = NULL;
*out_authdata = authdata;
return 0;
}
static krb5_error_code
mspac_verify(krb5_context kcontext,
krb5_authdata_context context,
void *plugin_context,
void *request_context,
const krb5_auth_context *auth_context,
const krb5_keyblock *key,
const krb5_ap_req *req)
{
krb5_error_code code;
struct mspac_context *pacctx = (struct mspac_context *)request_context;
if (pacctx->pac == NULL)
return EINVAL;
code = krb5_pac_verify(kcontext, pacctx->pac,
req->ticket->enc_part2->times.authtime,
req->ticket->enc_part2->client, key, NULL);
if (code != 0)
TRACE_MSPAC_VERIFY_FAIL(kcontext, code);
/*
* If the above verification failed, don't fail the whole authentication,
* just don't mark the PAC as verified. A checksum mismatch can occur if
* the PAC was copied from a cross-realm TGT by an ignorant KDC, and Apple
* Mac OS X Server Open Directory (as of 10.6) generates PACs with no
* server checksum at all.
*/
return 0;
}
static void
mspac_request_fini(krb5_context kcontext,
krb5_authdata_context context,
void *plugin_context,
void *request_context)
{
struct mspac_context *pacctx = (struct mspac_context *)request_context;
if (pacctx != NULL) {
if (pacctx->pac != NULL)
krb5_pac_free(kcontext, pacctx->pac);
free(pacctx);
}
}
#define STRLENOF(x) (sizeof((x)) - 1)
static struct {
krb5_ui_4 type;
krb5_data attribute;
} mspac_attribute_types[] = {
{ (krb5_ui_4)-1, { KV5M_DATA, STRLENOF("urn:mspac:"),
"urn:mspac:" } },
{ KRB5_PAC_LOGON_INFO, { KV5M_DATA,
STRLENOF("urn:mspac:logon-info"),
"urn:mspac:logon-info" } },
{ KRB5_PAC_CREDENTIALS_INFO, { KV5M_DATA,
STRLENOF("urn:mspac:credentials-info"),
"urn:mspac:credentials-info" } },
{ KRB5_PAC_SERVER_CHECKSUM, { KV5M_DATA,
STRLENOF("urn:mspac:server-checksum"),
"urn:mspac:server-checksum" } },
{ KRB5_PAC_PRIVSVR_CHECKSUM, { KV5M_DATA,
STRLENOF("urn:mspac:privsvr-checksum"),
"urn:mspac:privsvr-checksum" } },
{ KRB5_PAC_CLIENT_INFO, { KV5M_DATA,
STRLENOF("urn:mspac:client-info"),
"urn:mspac:client-info" } },
{ KRB5_PAC_DELEGATION_INFO, { KV5M_DATA,
STRLENOF("urn:mspac:delegation-info"),
"urn:mspac:delegation-info" } },
{ KRB5_PAC_UPN_DNS_INFO, { KV5M_DATA,
STRLENOF("urn:mspac:upn-dns-info"),
"urn:mspac:upn-dns-info" } },
};
#define MSPAC_ATTRIBUTE_COUNT (sizeof(mspac_attribute_types)/sizeof(mspac_attribute_types[0]))
static krb5_error_code
mspac_type2attr(krb5_ui_4 type, krb5_data *attr)
{
unsigned int i;
for (i = 0; i < MSPAC_ATTRIBUTE_COUNT; i++) {
if (mspac_attribute_types[i].type == type) {
*attr = mspac_attribute_types[i].attribute;
return 0;
}
}
return ENOENT;
}
static krb5_error_code
mspac_attr2type(const krb5_data *attr, krb5_ui_4 *type)
{
unsigned int i;
for (i = 0; i < MSPAC_ATTRIBUTE_COUNT; i++) {
if (attr->length == mspac_attribute_types[i].attribute.length &&
strncasecmp(attr->data, mspac_attribute_types[i].attribute.data, attr->length) == 0) {
*type = mspac_attribute_types[i].type;
return 0;
}
}
if (attr->length > STRLENOF("urn:mspac:") &&
strncasecmp(attr->data, "urn:mspac:", STRLENOF("urn:mspac:")) == 0)
{
char *p = &attr->data[STRLENOF("urn:mspac:")];
char *endptr;
*type = strtoul(p, &endptr, 10);
if (*type != 0 && *endptr == '\0')
return 0;
}
return ENOENT;
}
static krb5_error_code
mspac_get_attribute_types(krb5_context kcontext,
krb5_authdata_context context,
void *plugin_context,
void *request_context,
krb5_data **out_attrs)
{
struct mspac_context *pacctx = (struct mspac_context *)request_context;
unsigned int i, j;
krb5_data *attrs;
krb5_error_code code;
if (pacctx->pac == NULL)
return ENOENT;
attrs = calloc(1 + pacctx->pac->pac->cBuffers + 1, sizeof(krb5_data));
if (attrs == NULL)
return ENOMEM;
j = 0;
/* The entire PAC */
code = krb5int_copy_data_contents(kcontext,
&mspac_attribute_types[0].attribute,
&attrs[j++]);
if (code != 0) {
free(attrs);
return code;
}
/* PAC buffers */
for (i = 0; i < pacctx->pac->pac->cBuffers; i++) {
krb5_data attr;
code = mspac_type2attr(pacctx->pac->pac->Buffers[i].ulType, &attr);
if (code == 0) {
code = krb5int_copy_data_contents(kcontext, &attr, &attrs[j++]);
if (code != 0) {
krb5int_free_data_list(kcontext, attrs);
return code;
}
} else {
int length;
length = asprintf(&attrs[j].data, "urn:mspac:%d",
pacctx->pac->pac->Buffers[i].ulType);
if (length < 0) {
krb5int_free_data_list(kcontext, attrs);
return ENOMEM;
}
attrs[j++].length = length;
}
}
attrs[j].data = NULL;
attrs[j].length = 0;
*out_attrs = attrs;
return 0;
}
static krb5_error_code
mspac_get_attribute(krb5_context kcontext,
krb5_authdata_context context,
void *plugin_context,
void *request_context,
const krb5_data *attribute,
krb5_boolean *authenticated,
krb5_boolean *complete,
krb5_data *value,
krb5_data *display_value,
int *more)
{
struct mspac_context *pacctx = (struct mspac_context *)request_context;
krb5_error_code code;
krb5_ui_4 type;
if (display_value != NULL) {
display_value->data = NULL;
display_value->length = 0;
}
if (*more != -1 || pacctx->pac == NULL)
return ENOENT;
/* If it didn't verify, pretend it didn't exist. */
if (!pacctx->pac->verified) {
TRACE_MSPAC_DISCARD_UNVERF(kcontext);
return ENOENT;
}
code = mspac_attr2type(attribute, &type);
if (code != 0)
return code;
/* -1 is a magic type that refers to the entire PAC */
if (type == (krb5_ui_4)-1) {
if (value != NULL)
code = krb5int_copy_data_contents(kcontext,
&pacctx->pac->data,
value);
else
code = 0;
} else {
if (value != NULL)
code = krb5_pac_get_buffer(kcontext, pacctx->pac, type, value);
else
code = k5_pac_locate_buffer(kcontext, pacctx->pac, type, NULL);
}
if (code == 0) {
*authenticated = pacctx->pac->verified;
*complete = TRUE;
}
*more = 0;
return code;
}
static krb5_error_code
mspac_set_attribute(krb5_context kcontext,
krb5_authdata_context context,
void *plugin_context,
void *request_context,
krb5_boolean complete,
const krb5_data *attribute,
const krb5_data *value)
{
struct mspac_context *pacctx = (struct mspac_context *)request_context;
krb5_error_code code;
krb5_ui_4 type;
if (pacctx->pac == NULL)
return ENOENT;
code = mspac_attr2type(attribute, &type);
if (code != 0)
return code;
/* -1 is a magic type that refers to the entire PAC */
if (type == (krb5_ui_4)-1) {
krb5_pac newpac;
code = krb5_pac_parse(kcontext, value->data, value->length, &newpac);
if (code != 0)
return code;
krb5_pac_free(kcontext, pacctx->pac);
pacctx->pac = newpac;
} else {
code = krb5_pac_add_buffer(kcontext, pacctx->pac, type, value);
}
return code;
}
static krb5_error_code
mspac_export_internal(krb5_context kcontext,
krb5_authdata_context context,
void *plugin_context,
void *request_context,
krb5_boolean restrict_authenticated,
void **ptr)
{
struct mspac_context *pacctx = (struct mspac_context *)request_context;
krb5_error_code code;
krb5_pac pac;
*ptr = NULL;
if (pacctx->pac == NULL)
return ENOENT;
if (restrict_authenticated && (pacctx->pac->verified) == FALSE)
return ENOENT;
code = krb5_pac_parse(kcontext, pacctx->pac->data.data,
pacctx->pac->data.length, &pac);
if (code == 0) {
pac->verified = pacctx->pac->verified;
*ptr = pac;
}
return code;
}
static void
mspac_free_internal(krb5_context kcontext,
krb5_authdata_context context,
void *plugin_context,
void *request_context,
void *ptr)
{
if (ptr != NULL)
krb5_pac_free(kcontext, (krb5_pac)ptr);
return;
}
static krb5_error_code
mspac_size(krb5_context kcontext,
krb5_authdata_context context,
void *plugin_context,
void *request_context,
size_t *sizep)
{
struct mspac_context *pacctx = (struct mspac_context *)request_context;
*sizep += sizeof(krb5_int32);
if (pacctx->pac != NULL)
*sizep += pacctx->pac->data.length;
*sizep += sizeof(krb5_int32);
return 0;
}
static krb5_error_code
mspac_externalize(krb5_context kcontext,
krb5_authdata_context context,
void *plugin_context,
void *request_context,
krb5_octet **buffer,
size_t *lenremain)
{
krb5_error_code code = 0;
struct mspac_context *pacctx = (struct mspac_context *)request_context;
size_t required = 0;
krb5_octet *bp;
size_t remain;
bp = *buffer;
remain = *lenremain;
if (pacctx->pac != NULL) {
mspac_size(kcontext, context, plugin_context,
request_context, &required);
if (required <= remain) {
krb5_ser_pack_int32((krb5_int32)pacctx->pac->data.length,
&bp, &remain);
krb5_ser_pack_bytes((krb5_octet *)pacctx->pac->data.data,
(size_t)pacctx->pac->data.length,
&bp, &remain);
krb5_ser_pack_int32((krb5_int32)pacctx->pac->verified,
&bp, &remain);
} else {
code = ENOMEM;
}
} else {
krb5_ser_pack_int32(0, &bp, &remain); /* length */
krb5_ser_pack_int32(0, &bp, &remain); /* verified */
}
*buffer = bp;
*lenremain = remain;
return code;
}
static krb5_error_code
mspac_internalize(krb5_context kcontext,
krb5_authdata_context context,
void *plugin_context,
void *request_context,
krb5_octet **buffer,
size_t *lenremain)
{
struct mspac_context *pacctx = (struct mspac_context *)request_context;
krb5_error_code code;
krb5_int32 ibuf;
krb5_octet *bp;
size_t remain;
krb5_pac pac = NULL;
bp = *buffer;
remain = *lenremain;
/* length */
code = krb5_ser_unpack_int32(&ibuf, &bp, &remain);
if (code != 0)
return code;
if (ibuf != 0) {
code = krb5_pac_parse(kcontext, bp, ibuf, &pac);
if (code != 0)
return code;
bp += ibuf;
remain -= ibuf;
}
/* verified */
code = krb5_ser_unpack_int32(&ibuf, &bp, &remain);
if (code != 0) {
krb5_pac_free(kcontext, pac);
return code;
}
if (pac != NULL) {
pac->verified = (ibuf != 0);
}
if (pacctx->pac != NULL) {
krb5_pac_free(kcontext, pacctx->pac);
}
pacctx->pac = pac;
*buffer = bp;
*lenremain = remain;
return 0;
}
static krb5_error_code
mspac_copy(krb5_context kcontext,
krb5_authdata_context context,
void *plugin_context,
void *request_context,
void *dst_plugin_context,
void *dst_request_context)
{
struct mspac_context *srcctx = (struct mspac_context *)request_context;
struct mspac_context *dstctx = (struct mspac_context *)dst_request_context;
krb5_error_code code = 0;
assert(dstctx != NULL);
assert(dstctx->pac == NULL);
if (srcctx->pac != NULL)
code = k5_pac_copy(kcontext, srcctx->pac, &dstctx->pac);
return code;
}
static krb5_authdatatype mspac_ad_types[] = { KRB5_AUTHDATA_WIN2K_PAC, 0 };
krb5plugin_authdata_client_ftable_v0 krb5int_mspac_authdata_client_ftable = {
"mspac",
mspac_ad_types,
mspac_init,
mspac_fini,
mspac_flags,
mspac_request_init,
mspac_request_fini,
mspac_get_attribute_types,
mspac_get_attribute,
mspac_set_attribute,
NULL, /* delete_attribute_proc */
mspac_export_authdata,
mspac_import_authdata,
mspac_export_internal,
mspac_free_internal,
mspac_verify,
mspac_size,
mspac_externalize,
mspac_internalize,
mspac_copy
};
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