gnupg/agent/learncard.c

449 lines
10 KiB
C

/* learncard.c - Handle the LEARN command
* Copyright (C) 2002, 2003 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 <ctype.h>
#include <assert.h>
#include <unistd.h>
#include <sys/stat.h>
#include "agent.h"
#include <assuan.h>
struct keypair_info_s {
struct keypair_info_s *next;
int no_cert;
char *id; /* points into grip */
char hexgrip[1];
};
typedef struct keypair_info_s *KEYPAIR_INFO;
struct kpinfo_cb_parm_s {
int error;
KEYPAIR_INFO info;
};
struct certinfo_s {
struct certinfo_s *next;
int type;
int done;
char id[1];
};
typedef struct certinfo_s *CERTINFO;
struct certinfo_cb_parm_s {
int error;
CERTINFO info;
};
struct sinfo_s {
struct sinfo_s *next;
char *data; /* Points into keyword. */
char keyword[1];
};
typedef struct sinfo_s *SINFO;
struct sinfo_cb_parm_s {
int error;;
SINFO info;
};
static void
release_keypair_info (KEYPAIR_INFO info)
{
while (info)
{
KEYPAIR_INFO tmp = info->next;
xfree (info);
info = tmp;
}
}
static void
release_certinfo (CERTINFO info)
{
while (info)
{
CERTINFO tmp = info->next;
xfree (info);
info = tmp;
}
}
static void
release_sinfo (SINFO info)
{
while (info)
{
SINFO tmp = info->next;
xfree (info);
info = tmp;
}
}
/* This callback is used by agent_card_learn and passed the content of
all KEYPAIRINFO lines. It merely stores this data away */
static void
kpinfo_cb (void *opaque, const char *line)
{
struct kpinfo_cb_parm_s *parm = opaque;
KEYPAIR_INFO item;
char *p;
if (parm->error)
return; /* no need to gather data after an error coccured */
item = xtrycalloc (1, sizeof *item + strlen (line));
if (!item)
{
parm->error = out_of_core ();
return;
}
strcpy (item->hexgrip, line);
for (p = item->hexgrip; hexdigitp (p); p++)
;
if (p == item->hexgrip && *p == 'X' && spacep (p+1))
{
item->no_cert = 1;
p++;
}
else if ((p - item->hexgrip) != 40 || !spacep (p))
{ /* not a 20 byte hex keygrip or not followed by a space */
parm->error = gpg_error (GPG_ERR_INV_RESPONSE);
xfree (item);
return;
}
*p++ = 0;
while (spacep (p))
p++;
item->id = p;
while (*p && !spacep (p))
p++;
if (p == item->id)
{ /* invalid ID string */
parm->error = gpg_error (GPG_ERR_INV_RESPONSE);
xfree (item);
return;
}
*p = 0; /* ignore trailing stuff */
/* store it */
item->next = parm->info;
parm->info = item;
}
/* This callback is used by agent_card_learn and passed the content of
all CERTINFO lines. It merely stores this data away */
static void
certinfo_cb (void *opaque, const char *line)
{
struct certinfo_cb_parm_s *parm = opaque;
CERTINFO item;
int type;
char *p, *pend;
if (parm->error)
return; /* no need to gather data after an error coccured */
type = strtol (line, &p, 10);
while (spacep (p))
p++;
for (pend = p; *pend && !spacep (pend); pend++)
;
if (p == pend || !*p)
{
parm->error = gpg_error (GPG_ERR_INV_RESPONSE);
return;
}
*pend = 0; /* ignore trailing stuff */
item = xtrycalloc (1, sizeof *item + strlen (p));
if (!item)
{
parm->error = out_of_core ();
return;
}
item->type = type;
strcpy (item->id, p);
/* store it */
item->next = parm->info;
parm->info = item;
}
/* This callback is used by agent_card_learn and passed the content of
all SINFO lines. It merely stores this data away */
static void
sinfo_cb (void *opaque, const char *keyword, size_t keywordlen,
const char *data)
{
struct sinfo_cb_parm_s *sparm = opaque;
SINFO item;
if (sparm->error)
return; /* no need to gather data after an error coccured */
item = xtrycalloc (1, sizeof *item + keywordlen + 1 + strlen (data));
if (!item)
{
sparm->error = out_of_core ();
return;
}
memcpy (item->keyword, keyword, keywordlen);
item->data = item->keyword + keywordlen;
*item->data = 0;
item->data++;
strcpy (item->data, data);
/* store it */
item->next = sparm->info;
sparm->info = item;
}
/* Create an S-expression with the shadow info. */
static unsigned char *
make_shadow_info (const char *serialno, const char *idstring)
{
const char *s;
unsigned char *info, *p;
char numbuf[21];
int n;
for (s=serialno, n=0; *s && s[1]; s += 2)
n++;
info = p = xtrymalloc (1 + 21 + n
+ 21 + strlen (idstring) + 1 + 1);
*p++ = '(';
sprintf (numbuf, "%d:", n);
p = stpcpy (p, numbuf);
for (s=serialno; *s && s[1]; s += 2)
*p++ = xtoi_2 (s);
sprintf (numbuf, "%d:", strlen (idstring));
p = stpcpy (p, numbuf);
p = stpcpy (p, idstring);
*p++ = ')';
*p = 0;
return info;
}
static int
send_cert_back (const char *id, void *assuan_context)
{
int rc;
char *derbuf;
size_t derbuflen;
rc = agent_card_readcert (id, &derbuf, &derbuflen);
if (rc)
{
log_error ("error reading certificate: %s\n",
gpg_strerror (rc));
return rc;
}
rc = assuan_send_data (assuan_context, derbuf, derbuflen);
xfree (derbuf);
if (!rc)
rc = assuan_send_data (assuan_context, NULL, 0);
if (!rc)
rc = assuan_write_line (assuan_context, "END");
if (rc)
{
log_error ("sending certificate failed: %s\n",
assuan_strerror (rc));
return map_assuan_err (rc);
}
return 0;
}
/* Perform the learn operation. If ASSUAN_CONTEXT is not NULL all new
certificates are send via Assuan */
int
agent_handle_learn (void *assuan_context)
{
int rc;
struct kpinfo_cb_parm_s parm;
struct certinfo_cb_parm_s cparm;
struct sinfo_cb_parm_s sparm;
char *serialno = NULL;
KEYPAIR_INFO item;
SINFO sitem;
unsigned char grip[20];
char *p;
int i;
static int certtype_list[] = {
101, /* trusted */
102, /* useful */
100, /* regular */
-1 /* end of list */
};
memset (&parm, 0, sizeof parm);
memset (&cparm, 0, sizeof cparm);
memset (&sparm, 0, sizeof sparm);
/* Check whether a card is present and get the serial number */
rc = agent_card_serialno (&serialno);
if (rc)
goto leave;
/* now gather all the available info */
rc = agent_card_learn (kpinfo_cb, &parm, certinfo_cb, &cparm,
sinfo_cb, &sparm);
if (!rc && (parm.error || cparm.error || sparm.error))
rc = parm.error? parm.error : cparm.error? cparm.error : sparm.error;
if (rc)
{
log_debug ("agent_card_learn failed: %s\n", gpg_strerror (rc));
goto leave;
}
log_info ("card has S/N: %s\n", serialno);
/* Pass on all the collected status information. */
if (assuan_context)
{
for (sitem = sparm.info; sitem; sitem = sitem->next)
{
assuan_write_status (assuan_context, sitem->keyword, sitem->data);
}
}
/* Write out the certificates in a standard order. */
for (i=0; certtype_list[i] != -1; i++)
{
CERTINFO citem;
for (citem = cparm.info; citem; citem = citem->next)
{
if (certtype_list[i] != citem->type)
continue;
if (opt.verbose)
log_info (" id: %s (type=%d)\n",
citem->id, citem->type);
if (assuan_context)
{
rc = send_cert_back (citem->id, assuan_context);
if (rc)
goto leave;
citem->done = 1;
}
}
}
for (item = parm.info; item; item = item->next)
{
unsigned char *pubkey, *shdkey;
size_t n;
if (opt.verbose)
log_info (" id: %s (grip=%s)\n", item->id, item->hexgrip);
if (item->no_cert)
continue; /* no public key yet available */
for (p=item->hexgrip, i=0; i < 20; p += 2, i++)
grip[i] = xtoi_2 (p);
if (!agent_key_available (grip))
continue;
/* unknown - store it */
rc = agent_card_readkey (item->id, &pubkey);
if (rc)
{
log_debug ("agent_card_readkey failed: %s\n", gpg_strerror (rc));
goto leave;
}
{
unsigned char *shadow_info = make_shadow_info (serialno, item->id);
if (!shadow_info)
{
rc = gpg_error (GPG_ERR_ENOMEM);
xfree (pubkey);
goto leave;
}
rc = agent_shadow_key (pubkey, shadow_info, &shdkey);
xfree (shadow_info);
}
xfree (pubkey);
if (rc)
{
log_error ("shadowing the key failed: %s\n", gpg_strerror (rc));
goto leave;
}
n = gcry_sexp_canon_len (shdkey, 0, NULL, NULL);
assert (n);
rc = agent_write_private_key (grip, shdkey, n, 0);
xfree (shdkey);
if (rc)
{
log_error ("error writing key: %s\n", gpg_strerror (rc));
goto leave;
}
if (opt.verbose)
log_info ("stored\n");
if (assuan_context)
{
CERTINFO citem;
/* only send the certificate if we have not done so before */
for (citem = cparm.info; citem; citem = citem->next)
{
if (!strcmp (citem->id, item->id))
break;
}
if (!citem)
{
rc = send_cert_back (item->id, assuan_context);
if (rc)
goto leave;
}
}
}
leave:
xfree (serialno);
release_keypair_info (parm.info);
release_certinfo (cparm.info);
release_sinfo (sparm.info);
return rc;
}