Page MenuHome GnuPG
Files F34109904

card-p15.c
No OneTemporary
Actions

card-p15.c
View Options

/* card-p15.c - PKCS-15 based card access
* Copyright (C) 2002 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* GnuPG is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* GnuPG is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#include <config.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#ifdef HAVE_OPENSC
#include <opensc/pkcs15.h>
#include "scdaemon.h"
#include <ksba.h>
#include "card-common.h"
struct p15private_s {
int n_prkey_rsa_objs;
struct sc_pkcs15_object *prkey_rsa_objs[32];
int n_cert_objs;
struct sc_pkcs15_object *cert_objs[32];
};
/* Allocate private data. */
static int
init_private_data (CARD card)
{
struct p15private_s *priv;
int rc;
if (card->p15priv)
return 0; /* already done. */
priv = xtrycalloc (1, sizeof *priv);
if (!priv)
return out_of_core ();
/* OpenSC (0.7.0) is a bit strange in that the get_objects functions
tries to be a bit too clever and implicitly does an enumeration
which eventually leads to the fact that every call to this
fucntion returns one more macthing object. The old code in
p15_enum_keypairs assume that it would alwyas return the same
numer of objects and used this to figure out what the last object
enumerated is. We now do an enum_objects just once and keep it
in the private data. */
rc = sc_pkcs15_get_objects (card->p15card, SC_PKCS15_TYPE_PRKEY_RSA,
priv->prkey_rsa_objs,
DIM (priv->prkey_rsa_objs));
if (rc < 0)
{
log_error ("private keys enumeration failed: %s\n", sc_strerror (rc));
xfree (priv);
return gpg_error (GPG_ERR_CARD);
}
priv->n_prkey_rsa_objs = rc;
/* Read all certificate objects. */
rc = sc_pkcs15_get_objects (card->p15card, SC_PKCS15_TYPE_CERT_X509,
priv->cert_objs,
DIM (priv->cert_objs));
if (rc < 0)
{
log_error ("private keys enumeration failed: %s\n", sc_strerror (rc));
xfree (priv);
return gpg_error (GPG_ERR_CARD);
}
priv->n_cert_objs = rc;
card->p15priv = priv;
return 0;
}
/* Release private data used in this module. */
void
p15_release_private_data (CARD card)
{
if (!card->p15priv)
return;
xfree (card->p15priv);
card->p15priv = NULL;
}
/* See card.c for interface description */
static int
p15_enum_keypairs (CARD card, int idx,
unsigned char *keygrip, char **keyid)
{
int rc;
struct p15private_s *priv;
struct sc_pkcs15_object *tmpobj;
int nobjs;
struct sc_pkcs15_prkey_info *pinfo;
struct sc_pkcs15_cert_info *certinfo;
struct sc_pkcs15_cert *certder;
ksba_cert_t cert;
rc = init_private_data (card);
if (rc)
return rc;
priv = card->p15priv;
nobjs = priv->n_prkey_rsa_objs;
rc = 0;
if (idx >= nobjs)
return -1;
pinfo = priv->prkey_rsa_objs[idx]->data;
/* now we need to read the certificate so that we can calculate the
keygrip */
rc = sc_pkcs15_find_cert_by_id (card->p15card, &pinfo->id, &tmpobj);
if (rc)
{
log_info ("certificate for private key %d not found: %s\n",
idx, sc_strerror (rc));
/* note, that we return the ID anyway */
rc = gpg_error (GPG_ERR_MISSING_CERT);
goto return_keyid;
}
certinfo = tmpobj->data;
rc = sc_pkcs15_read_certificate (card->p15card, certinfo, &certder);
if (rc)
{
log_info ("failed to read certificate for private key %d: %s\n",
idx, sc_strerror (rc));
return gpg_error (GPG_ERR_CARD);
}
rc = ksba_cert_new (&cert);
if (rc)
{
sc_pkcs15_free_certificate (certder);
return rc;
}
rc = ksba_cert_init_from_mem (cert, certder->data, certder->data_len);
sc_pkcs15_free_certificate (certder);
if (rc)
{
log_error ("failed to parse the certificate for private key %d: %s\n",
idx, gpg_strerror (rc));
ksba_cert_release (cert);
return rc;
}
if (card_help_get_keygrip (cert, keygrip))
{
log_error ("failed to calculate the keygrip of private key %d\n", idx);
ksba_cert_release (cert);
return gpg_error (GPG_ERR_CARD);
}
ksba_cert_release (cert);
rc = 0;
return_keyid:
if (keyid)
{
char *p;
int i;
*keyid = p = xtrymalloc (9+pinfo->id.len*2+1);
if (!*keyid)
return out_of_core ();
p = stpcpy (p, "P15-5015.");
for (i=0; i < pinfo->id.len; i++, p += 2)
sprintf (p, "%02X", pinfo->id.value[i]);
*p = 0;
}
return rc;
}
/* See card.c for interface description */
static int
p15_enum_certs (CARD card, int idx, char **certid, int *type)
{
int rc;
struct p15private_s *priv;
struct sc_pkcs15_object *obj;
struct sc_pkcs15_cert_info *cinfo;
int nobjs;
rc = init_private_data (card);
if (rc)
return rc;
priv = card->p15priv;
nobjs = priv->n_cert_objs;
rc = 0;
if (idx >= nobjs)
return -1;
obj = priv->cert_objs[idx];
cinfo = obj->data;
if (certid)
{
char *p;
int i;
*certid = p = xtrymalloc (9+cinfo->id.len*2+1);
if (!*certid)
return out_of_core ();
p = stpcpy (p, "P15-5015.");
for (i=0; i < cinfo->id.len; i++, p += 2)
sprintf (p, "%02X", cinfo->id.value[i]);
*p = 0;
}
if (type)
{
if (!obj->df)
*type = 0; /* unknown */
else if (obj->df->type == SC_PKCS15_CDF)
*type = 100;
else if (obj->df->type == SC_PKCS15_CDF_TRUSTED)
*type = 101;
else if (obj->df->type == SC_PKCS15_CDF_USEFUL)
*type = 102;
else
*type = 0; /* error -> unknown */
}
return rc;
}
static int
idstr_to_id (const char *idstr, struct sc_pkcs15_id *id)
{
const char *s;
int n;
/* For now we only support the standard DF */
if (strncmp (idstr, "P15-5015.", 9) )
return gpg_error (GPG_ERR_INV_ID);
for (s=idstr+9, n=0; hexdigitp (s); s++, n++)
;
if (*s || (n&1))
return gpg_error (GPG_ERR_INV_ID); /*invalid or odd number of digits*/
n /= 2;
if (!n || n > SC_PKCS15_MAX_ID_SIZE)
return gpg_error (GPG_ERR_INV_ID); /* empty or too large */
for (s=idstr+9, n=0; *s; s += 2, n++)
id->value[n] = xtoi_2 (s);
id->len = n;
return 0;
}
/* See card.c for interface description */
static int
p15_read_cert (CARD card, const char *certidstr,
unsigned char **cert, size_t *ncert)
{
struct sc_pkcs15_object *tmpobj;
struct sc_pkcs15_id certid;
struct sc_pkcs15_cert_info *certinfo;
struct sc_pkcs15_cert *certder;
int rc;
if (!card || !certidstr || !cert || !ncert)
return gpg_error (GPG_ERR_INV_VALUE);
if (!card->p15card)
return gpg_error (GPG_ERR_NO_PKCS15_APP);
rc = idstr_to_id (certidstr, &certid);
if (rc)
return rc;
rc = sc_pkcs15_find_cert_by_id (card->p15card, &certid, &tmpobj);
if (rc)
{
log_info ("certificate '%s' not found: %s\n",
certidstr, sc_strerror (rc));
return -1;
}
certinfo = tmpobj->data;
rc = sc_pkcs15_read_certificate (card->p15card, certinfo, &certder);
if (rc)
{
log_info ("failed to read certificate '%s': %s\n",
certidstr, sc_strerror (rc));
return gpg_error (GPG_ERR_CARD);
}
*cert = xtrymalloc (certder->data_len);
if (!*cert)
{
gpg_error_t tmperr = out_of_core ();
sc_pkcs15_free_certificate (certder);
return tmperr;
}
memcpy (*cert, certder->data, certder->data_len);
*ncert = certder->data_len;
sc_pkcs15_free_certificate (certder);
return 0;
}
static int
p15_prepare_key (CARD card, const char *keyidstr,
int (pincb)(void*, const char *, char **),
void *pincb_arg, struct sc_pkcs15_object **r_keyobj)
{
struct sc_pkcs15_id keyid;
struct sc_pkcs15_pin_info *pin;
struct sc_pkcs15_object *keyobj, *pinobj;
char *pinvalue;
int rc;
rc = idstr_to_id (keyidstr, &keyid);
if (rc)
return rc;
rc = sc_pkcs15_find_prkey_by_id (card->p15card, &keyid, &keyobj);
if (rc < 0)
{
log_error ("private key not found: %s\n", sc_strerror(rc));
return gpg_error (GPG_ERR_NO_SECKEY);
}
rc = sc_pkcs15_find_pin_by_auth_id (card->p15card,
&keyobj->auth_id, &pinobj);
if (rc)
{
log_error ("failed to find PIN by auth ID: %s\n", sc_strerror (rc));
return gpg_error (GPG_ERR_BAD_PIN_METHOD);
}
pin = pinobj->data;
/* Fixme: pack this into a verification loop */
/* Fixme: we might want to pass pin->min_length and
pin->stored_length */
rc = pincb (pincb_arg, pinobj->label, &pinvalue);
if (rc)
{
log_info ("PIN callback returned error: %s\n", gpg_strerror (rc));
return rc;
}
rc = sc_pkcs15_verify_pin (card->p15card, pin,
pinvalue, strlen (pinvalue));
xfree (pinvalue);
if (rc)
{
log_info ("PIN verification failed: %s\n", sc_strerror (rc));
return gpg_error (GPG_ERR_BAD_PIN);
}
/* fixme: check wheter we need to release KEYOBJ in case of an error */
*r_keyobj = keyobj;
return 0;
}
/* See card.c for interface description */
static int
p15_sign (CARD card, const char *keyidstr, int hashalgo,
int (pincb)(void*, const char *, char **),
void *pincb_arg,
const void *indata, size_t indatalen,
unsigned char **outdata, size_t *outdatalen )
{
unsigned int cryptflags;
struct sc_pkcs15_object *keyobj;
int rc;
unsigned char *outbuf = NULL;
size_t outbuflen;
if (hashalgo != GCRY_MD_SHA1)
return gpg_error (GPG_ERR_UNSUPPORTED_ALGORITHM);
rc = p15_prepare_key (card, keyidstr, pincb, pincb_arg, &keyobj);
if (rc)
return rc;
cryptflags = SC_ALGORITHM_RSA_PAD_PKCS1;
outbuflen = 1024;
outbuf = xtrymalloc (outbuflen);
if (!outbuf)
return out_of_core ();
rc = sc_pkcs15_compute_signature (card->p15card, keyobj,
cryptflags,
indata, indatalen,
outbuf, outbuflen );
if (rc < 0)
{
log_error ("failed to create signature: %s\n", sc_strerror (rc));
rc = gpg_error (GPG_ERR_CARD);
}
else
{
*outdatalen = rc;
*outdata = outbuf;
outbuf = NULL;
rc = 0;
}
xfree (outbuf);
return rc;
}
/* See card.c for description */
static int
p15_decipher (CARD card, const char *keyidstr,
int (pincb)(void*, const char *, char **),
void *pincb_arg,
const void *indata, size_t indatalen,
unsigned char **outdata, size_t *outdatalen )
{
struct sc_pkcs15_object *keyobj;
int rc;
unsigned char *outbuf = NULL;
size_t outbuflen;
rc = p15_prepare_key (card, keyidstr, pincb, pincb_arg, &keyobj);
if (rc)
return rc;
if (card && card->scard && card->scard->driver
&& !strcasecmp (card->scard->driver->short_name, "tcos"))
{
/* very ugly hack to force the use of a local key. We need this
until we have fixed the initialization code for TCOS cards */
struct sc_pkcs15_prkey_info *prkey = keyobj->data;
if ( !(prkey->key_reference & 0x80))
{
prkey->key_reference |= 0x80;
log_debug ("using TCOS hack to force the use of local keys\n");
}
if (*keyidstr && keyidstr[strlen(keyidstr)-1] == '6')
{
prkey->key_reference |= 1;
log_debug ("warning: using even more TCOS hacks\n");
}
}
outbuflen = indatalen < 256? 256 : indatalen;
outbuf = xtrymalloc (outbuflen);
if (!outbuf)
return out_of_core ();
rc = sc_pkcs15_decipher (card->p15card, keyobj,
0,
indata, indatalen,
outbuf, outbuflen);
if (rc < 0)
{
log_error ("failed to decipher the data: %s\n", sc_strerror (rc));
rc = gpg_error (GPG_ERR_CARD);
}
else
{
*outdatalen = rc;
*outdata = outbuf;
outbuf = NULL;
rc = 0;
}
xfree (outbuf);
return rc;
}
/* Bind our operations to the card */
void
card_p15_bind (CARD card)
{
card->fnc.enum_keypairs = p15_enum_keypairs;
card->fnc.enum_certs = p15_enum_certs;
card->fnc.read_cert = p15_read_cert;
card->fnc.sign = p15_sign;
card->fnc.decipher = p15_decipher;
}
#endif /*HAVE_OPENSC*/

File Metadata

Mime Type
text/x-c
Expires
Fri, Dec 5, 5:29 AM (7 h, 40 m)
Storage Engine
local-disk
Storage Format
Raw Data
Storage Handle
8d/73/cee8722f6753416eb69907879eb5

Event Timeline