qemu/libcacard/cac.c
Stefan Weil 754e72e195 libcacard/cac: Remove unused statement (value stored is never read)
Warning from ccc-analyzer:

libcacard/cac.c:192:13: warning: Value stored to 'ret' is never read
            ret = VCARD_DONE;
            ^     ~~~~~~~~~~

Here 'ret' is assigned a value inside of a switch statement and also after
that switch statement.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-12-02 21:07:02 +04:00

428 lines
13 KiB
C

/*
* implement the applets for the CAC card.
*
* This code is licensed under the GNU LGPL, version 2.1 or later.
* See the COPYING.LIB file in the top-level directory.
*/
#include "qemu-common.h"
#include "cac.h"
#include "vcard.h"
#include "vcard_emul.h"
#include "card_7816.h"
/* private data for PKI applets */
typedef struct CACPKIAppletDataStruct {
unsigned char *cert;
int cert_len;
unsigned char *cert_buffer;
int cert_buffer_len;
unsigned char *sign_buffer;
int sign_buffer_len;
VCardKey *key;
} CACPKIAppletData;
/*
* CAC applet private data
*/
struct VCardAppletPrivateStruct {
union {
CACPKIAppletData pki_data;
void *reserved;
} u;
};
/*
* handle all the APDU's that are common to all CAC applets
*/
static VCardStatus
cac_common_process_apdu(VCard *card, VCardAPDU *apdu, VCardResponse **response)
{
int ef;
VCardStatus ret = VCARD_FAIL;
switch (apdu->a_ins) {
case VCARD7816_INS_SELECT_FILE:
if (apdu->a_p1 != 0x02) {
/* let the 7816 code handle applet switches */
ret = VCARD_NEXT;
break;
}
/* handle file id setting */
if (apdu->a_Lc != 2) {
*response = vcard_make_response(
VCARD7816_STATUS_ERROR_DATA_INVALID);
ret = VCARD_DONE;
break;
}
/* CAC 1.0 only supports ef = 0 */
ef = apdu->a_body[0] | (apdu->a_body[1] << 8);
if (ef != 0) {
*response = vcard_make_response(
VCARD7816_STATUS_ERROR_FILE_NOT_FOUND);
ret = VCARD_DONE;
break;
}
*response = vcard_make_response(VCARD7816_STATUS_SUCCESS);
ret = VCARD_DONE;
break;
case VCARD7816_INS_GET_RESPONSE:
case VCARD7816_INS_VERIFY:
/* let the 7816 code handle these */
ret = VCARD_NEXT;
break;
case CAC_GET_PROPERTIES:
case CAC_GET_ACR:
/* skip these for now, this will probably be needed */
*response = vcard_make_response(VCARD7816_STATUS_ERROR_P1_P2_INCORRECT);
ret = VCARD_DONE;
break;
default:
*response = vcard_make_response(
VCARD7816_STATUS_ERROR_COMMAND_NOT_SUPPORTED);
ret = VCARD_DONE;
break;
}
return ret;
}
/*
* reset the inter call state between applet selects
*/
static VCardStatus
cac_applet_pki_reset(VCard *card, int channel)
{
VCardAppletPrivate *applet_private = NULL;
CACPKIAppletData *pki_applet = NULL;
applet_private = vcard_get_current_applet_private(card, channel);
assert(applet_private);
pki_applet = &(applet_private->u.pki_data);
pki_applet->cert_buffer = NULL;
if (pki_applet->sign_buffer) {
g_free(pki_applet->sign_buffer);
pki_applet->sign_buffer = NULL;
}
pki_applet->cert_buffer_len = 0;
pki_applet->sign_buffer_len = 0;
return VCARD_DONE;
}
static VCardStatus
cac_applet_pki_process_apdu(VCard *card, VCardAPDU *apdu,
VCardResponse **response)
{
CACPKIAppletData *pki_applet = NULL;
VCardAppletPrivate *applet_private = NULL;
int size, next;
unsigned char *sign_buffer;
vcard_7816_status_t status;
VCardStatus ret = VCARD_FAIL;
applet_private = vcard_get_current_applet_private(card, apdu->a_channel);
assert(applet_private);
pki_applet = &(applet_private->u.pki_data);
switch (apdu->a_ins) {
case CAC_UPDATE_BUFFER:
*response = vcard_make_response(
VCARD7816_STATUS_ERROR_CONDITION_NOT_SATISFIED);
ret = VCARD_DONE;
break;
case CAC_GET_CERTIFICATE:
if ((apdu->a_p2 != 0) || (apdu->a_p1 != 0)) {
*response = vcard_make_response(
VCARD7816_STATUS_ERROR_P1_P2_INCORRECT);
break;
}
assert(pki_applet->cert != NULL);
size = apdu->a_Le;
if (pki_applet->cert_buffer == NULL) {
pki_applet->cert_buffer = pki_applet->cert;
pki_applet->cert_buffer_len = pki_applet->cert_len;
}
size = MIN(size, pki_applet->cert_buffer_len);
next = MIN(255, pki_applet->cert_buffer_len - size);
*response = vcard_response_new_bytes(
card, pki_applet->cert_buffer, size,
apdu->a_Le, next ?
VCARD7816_SW1_WARNING_CHANGE :
VCARD7816_SW1_SUCCESS,
next);
pki_applet->cert_buffer += size;
pki_applet->cert_buffer_len -= size;
if ((*response == NULL) || (next == 0)) {
pki_applet->cert_buffer = NULL;
}
if (*response == NULL) {
*response = vcard_make_response(
VCARD7816_STATUS_EXC_ERROR_MEMORY_FAILURE);
}
ret = VCARD_DONE;
break;
case CAC_SIGN_DECRYPT:
if (apdu->a_p2 != 0) {
*response = vcard_make_response(
VCARD7816_STATUS_ERROR_P1_P2_INCORRECT);
break;
}
size = apdu->a_Lc;
sign_buffer = realloc(pki_applet->sign_buffer,
pki_applet->sign_buffer_len+size);
if (sign_buffer == NULL) {
g_free(pki_applet->sign_buffer);
pki_applet->sign_buffer = NULL;
pki_applet->sign_buffer_len = 0;
*response = vcard_make_response(
VCARD7816_STATUS_EXC_ERROR_MEMORY_FAILURE);
ret = VCARD_DONE;
break;
}
memcpy(sign_buffer+pki_applet->sign_buffer_len, apdu->a_body, size);
size += pki_applet->sign_buffer_len;
switch (apdu->a_p1) {
case 0x80:
/* p1 == 0x80 means we haven't yet sent the whole buffer, wait for
* the rest */
pki_applet->sign_buffer = sign_buffer;
pki_applet->sign_buffer_len = size;
*response = vcard_make_response(VCARD7816_STATUS_SUCCESS);
break;
case 0x00:
/* we now have the whole buffer, do the operation, result will be
* in the sign_buffer */
status = vcard_emul_rsa_op(card, pki_applet->key,
sign_buffer, size);
if (status != VCARD7816_STATUS_SUCCESS) {
*response = vcard_make_response(status);
break;
}
*response = vcard_response_new(card, sign_buffer, size, apdu->a_Le,
VCARD7816_STATUS_SUCCESS);
if (*response == NULL) {
*response = vcard_make_response(
VCARD7816_STATUS_EXC_ERROR_MEMORY_FAILURE);
}
break;
default:
*response = vcard_make_response(
VCARD7816_STATUS_ERROR_P1_P2_INCORRECT);
break;
}
g_free(sign_buffer);
pki_applet->sign_buffer = NULL;
pki_applet->sign_buffer_len = 0;
ret = VCARD_DONE;
break;
case CAC_READ_BUFFER:
/* new CAC call, go ahead and use the old version for now */
/* TODO: implement */
*response = vcard_make_response(
VCARD7816_STATUS_ERROR_COMMAND_NOT_SUPPORTED);
ret = VCARD_DONE;
break;
default:
ret = cac_common_process_apdu(card, apdu, response);
break;
}
return ret;
}
static VCardStatus
cac_applet_id_process_apdu(VCard *card, VCardAPDU *apdu,
VCardResponse **response)
{
VCardStatus ret = VCARD_FAIL;
switch (apdu->a_ins) {
case CAC_UPDATE_BUFFER:
*response = vcard_make_response(
VCARD7816_STATUS_ERROR_CONDITION_NOT_SATISFIED);
ret = VCARD_DONE;
break;
case CAC_READ_BUFFER:
/* new CAC call, go ahead and use the old version for now */
/* TODO: implement */
*response = vcard_make_response(
VCARD7816_STATUS_ERROR_COMMAND_NOT_SUPPORTED);
ret = VCARD_DONE;
break;
default:
ret = cac_common_process_apdu(card, apdu, response);
break;
}
return ret;
}
/*
* TODO: if we ever want to support general CAC middleware, we will need to
* implement the various containers.
*/
static VCardStatus
cac_applet_container_process_apdu(VCard *card, VCardAPDU *apdu,
VCardResponse **response)
{
VCardStatus ret = VCARD_FAIL;
switch (apdu->a_ins) {
case CAC_READ_BUFFER:
case CAC_UPDATE_BUFFER:
*response = vcard_make_response(
VCARD7816_STATUS_ERROR_COMMAND_NOT_SUPPORTED);
ret = VCARD_DONE;
break;
default:
ret = cac_common_process_apdu(card, apdu, response);
break;
}
return ret;
}
/*
* utilities for creating and destroying the private applet data
*/
static void
cac_delete_pki_applet_private(VCardAppletPrivate *applet_private)
{
CACPKIAppletData *pki_applet_data = NULL;
if (applet_private == NULL) {
return;
}
pki_applet_data = &(applet_private->u.pki_data);
if (pki_applet_data->cert != NULL) {
g_free(pki_applet_data->cert);
}
if (pki_applet_data->sign_buffer != NULL) {
g_free(pki_applet_data->sign_buffer);
}
if (pki_applet_data->key != NULL) {
vcard_emul_delete_key(pki_applet_data->key);
}
g_free(applet_private);
}
static VCardAppletPrivate *
cac_new_pki_applet_private(const unsigned char *cert,
int cert_len, VCardKey *key)
{
CACPKIAppletData *pki_applet_data = NULL;
VCardAppletPrivate *applet_private = NULL;
applet_private = (VCardAppletPrivate *)g_malloc(sizeof(VCardAppletPrivate));
pki_applet_data = &(applet_private->u.pki_data);
pki_applet_data->cert_buffer = NULL;
pki_applet_data->cert_buffer_len = 0;
pki_applet_data->sign_buffer = NULL;
pki_applet_data->sign_buffer_len = 0;
pki_applet_data->key = NULL;
pki_applet_data->cert = (unsigned char *)g_malloc(cert_len+1);
/*
* if we want to support compression, then we simply change the 0 to a 1
* and compress the cert data with libz
*/
pki_applet_data->cert[0] = 0; /* not compressed */
memcpy(&pki_applet_data->cert[1], cert, cert_len);
pki_applet_data->cert_len = cert_len+1;
pki_applet_data->key = key;
return applet_private;
}
/*
* create a new cac applet which links to a given cert
*/
static VCardApplet *
cac_new_pki_applet(int i, const unsigned char *cert,
int cert_len, VCardKey *key)
{
VCardAppletPrivate *applet_private = NULL;
VCardApplet *applet = NULL;
unsigned char pki_aid[] = { 0xa0, 0x00, 0x00, 0x00, 0x79, 0x01, 0x00 };
int pki_aid_len = sizeof(pki_aid);
pki_aid[pki_aid_len-1] = i;
applet_private = cac_new_pki_applet_private(cert, cert_len, key);
if (applet_private == NULL) {
goto failure;
}
applet = vcard_new_applet(cac_applet_pki_process_apdu, cac_applet_pki_reset,
pki_aid, pki_aid_len);
if (applet == NULL) {
goto failure;
}
vcard_set_applet_private(applet, applet_private,
cac_delete_pki_applet_private);
applet_private = NULL;
return applet;
failure:
if (applet_private != NULL) {
cac_delete_pki_applet_private(applet_private);
}
return NULL;
}
static unsigned char cac_default_container_aid[] = {
0xa0, 0x00, 0x00, 0x00, 0x30, 0x00, 0x00 };
static unsigned char cac_id_aid[] = {
0xa0, 0x00, 0x00, 0x00, 0x79, 0x03, 0x00 };
/*
* Initialize the cac card. This is the only public function in this file. All
* the rest are connected through function pointers.
*/
VCardStatus
cac_card_init(VReader *reader, VCard *card,
const char *params,
unsigned char * const *cert,
int cert_len[],
VCardKey *key[] /* adopt the keys*/,
int cert_count)
{
int i;
VCardApplet *applet;
/* CAC Cards are VM Cards */
vcard_set_type(card, VCARD_VM);
/* create one PKI applet for each cert */
for (i = 0; i < cert_count; i++) {
applet = cac_new_pki_applet(i, cert[i], cert_len[i], key[i]);
if (applet == NULL) {
goto failure;
}
vcard_add_applet(card, applet);
}
/* create a default blank container applet */
applet = vcard_new_applet(cac_applet_container_process_apdu,
NULL, cac_default_container_aid,
sizeof(cac_default_container_aid));
if (applet == NULL) {
goto failure;
}
vcard_add_applet(card, applet);
/* create a default blank container applet */
applet = vcard_new_applet(cac_applet_id_process_apdu,
NULL, cac_id_aid,
sizeof(cac_id_aid));
if (applet == NULL) {
goto failure;
}
vcard_add_applet(card, applet);
return VCARD_DONE;
failure:
return VCARD_FAIL;
}