scd: writekey support of ECC.

* scd/app-openpgp.c (CURVE_SEC_P256K1, get_algo_byte): New.
(store_fpr): Support ECC keys with varargs.
(get_ecc_key_parameters, get_curve_name): Support secp256k1.
(parse_ecc_curve): Likewise.
(build_ecdsa_privkey_template, rsa_writekey, ecdsa_writekey): New.
(ecdh_writekey): New.  Not implemented yet.
(do_writekey): Call rsa_writekey, ecdsa_writekey, or ecdh_writekey.
(do_genkey): Follow the change of store_fpr.

Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
This commit is contained in:
NIIBE Yutaka 2014-03-12 17:25:33 +09:00
parent 0b2cca807d
commit 781b941743
1 changed files with 424 additions and 93 deletions

View File

@ -1,6 +1,6 @@
/* app-openpgp.c - The OpenPGP card application.
* Copyright (C) 2003, 2004, 2005, 2007, 2008,
* 2009, 2013 Free Software Foundation, Inc.
* 2009, 2013, 2014 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
@ -45,6 +45,7 @@
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <assert.h>
#include <time.h>
@ -143,7 +144,9 @@ enum
{
CURVE_NIST_P256,
CURVE_NIST_P384,
CURVE_NIST_P521
CURVE_NIST_P521,
CURVE_SEC_P256K1,
CURVE_UNKOWN,
};
@ -735,24 +738,58 @@ parse_login_data (app_t app)
xfree (relptr);
}
static unsigned char
get_algo_byte (key_type_t key_type)
{
if (key_type == KEY_TYPE_ECDSA)
return 19;
else if (key_type == KEY_TYPE_ECDH)
return 18;
else
return 1; /* RSA */
}
#define MAX_ARGS_STORE_FPR 3
/* Note, that FPR must be at least 20 bytes. */
static gpg_error_t
store_fpr (app_t app, int keynumber, u32 timestamp,
const unsigned char *m, size_t mlen,
const unsigned char *e, size_t elen,
unsigned char *fpr, unsigned int card_version)
unsigned char *fpr, unsigned int card_version,
key_type_t key_type,
...)
{
unsigned int n, nbits;
unsigned char *buffer, *p;
int tag, tag2;
int rc;
const unsigned char *m[MAX_ARGS_STORE_FPR];
size_t mlen[MAX_ARGS_STORE_FPR];
va_list ap;
int argc;
int i;
for (; mlen && !*m; mlen--, m++) /* strip leading zeroes */
;
for (; elen && !*e; elen--, e++) /* strip leading zeroes */
;
n = 6; /* key packet version, 4-byte timestamps, and algorithm */
if (key_type == KEY_TYPE_RSA || key_type == KEY_TYPE_ECDSA)
argc = 2;
else if (key_type == KEY_TYPE_ECDH)
argc = 3;
else
return gpg_error (GPG_ERR_NOT_IMPLEMENTED);
va_start (ap, key_type);
for (i = 0; i < argc; i++)
{
m[i] = va_arg (ap, const unsigned char *);
mlen[i] = va_arg (ap, size_t);
for (; mlen[i] && !*m[i]; mlen[i]--, m[i]++) /* strip leading zeroes */
;
if (key_type == KEY_TYPE_RSA || i == 1)
n += 2;
n += mlen[i];
}
va_end (ap);
n = 6 + 2 + mlen + 2 + elen;
p = buffer = xtrymalloc (3 + n);
if (!buffer)
return gpg_error_from_syserror ();
@ -765,15 +802,19 @@ store_fpr (app_t app, int keynumber, u32 timestamp,
*p++ = timestamp >> 16;
*p++ = timestamp >> 8;
*p++ = timestamp;
*p++ = 1; /* RSA */
nbits = count_bits (m, mlen);
*p++ = nbits >> 8;
*p++ = nbits;
memcpy (p, m, mlen); p += mlen;
nbits = count_bits (e, elen);
*p++ = nbits >> 8;
*p++ = nbits;
memcpy (p, e, elen); p += elen;
*p++ = get_algo_byte (key_type);
for (i = 0; i < argc; i++)
{
if (key_type == KEY_TYPE_RSA || i == 1)
{
nbits = count_bits (m[i], mlen[i]);
*p++ = nbits >> 8;
*p++ = nbits;
}
memcpy (p, m[i], mlen[i]);
p += mlen[i];
}
gcry_md_hash_buffer (GCRY_MD_SHA1, fpr, buffer, n+3);
@ -889,11 +930,16 @@ get_ecc_key_parameters (int curve, int *r_n_bits, const char **r_curve_oid)
*r_n_bits = 384;
*r_curve_oid = "1.3.132.0.34";
}
else
else if (curve == CURVE_NIST_P521)
{
*r_n_bits = 521;
*r_curve_oid = "1.3.132.0.35";
}
else
{
*r_n_bits = 256;
*r_curve_oid = "1.3.132.0.10";
}
}
static void
@ -1234,8 +1280,10 @@ get_curve_name (int curve)
return "NIST P-256";
else if (curve == CURVE_NIST_P384)
return "NIST P-384";
else
else if (curve == CURVE_NIST_P521)
return "NIST P-521";
else
return "secp256k1";
}
@ -1456,7 +1504,7 @@ get_public_key (app_t app, int keyno)
= get_curve_name (app->app_local->keyattr[keyno].ecdsa.curve);
err = gcry_sexp_build (&s_pkey, NULL,
"(public-key(ecdsa(curve%s)(q%b)))",
"(public-key(ecc(curve%s)(q%b)))",
curve_name, mlen, mbuf);
if (err)
goto leave;
@ -2500,8 +2548,6 @@ add_tlv (unsigned char *buffer, unsigned int tag, size_t length)
}
/* Build the private key template as specified in the OpenPGP specs
v2.0 section 4.3.3.7. */
static gpg_error_t
build_privkey_template (app_t app, int keyno,
const unsigned char *rsa_n, size_t rsa_n_len,
@ -2648,6 +2694,74 @@ build_privkey_template (app_t app, int keyno,
return 0;
}
static gpg_error_t
build_ecdsa_privkey_template (app_t app, int keyno,
const unsigned char *ecc_d, size_t ecc_d_len,
unsigned char **result, size_t *resultlen)
{
unsigned char privkey[2];
size_t privkey_len;
unsigned char exthdr[2+2+1];
size_t exthdr_len;
unsigned char suffix[2+1];
size_t suffix_len;
unsigned char *tp;
size_t datalen;
unsigned char *template;
size_t template_size;
*result = NULL;
*resultlen = 0;
/* Build the 7f48 cardholder private key template. */
datalen = 0;
tp = privkey;
tp += add_tlv (tp, 0x91, ecc_d_len); /* Tag 0x91??? */
datalen += ecc_d_len;
privkey_len = tp - privkey;
/* Build the extended header list without the private key template. */
tp = exthdr;
*tp++ = keyno ==0 ? 0xb6 : keyno == 1? 0xb8 : 0xa4;
*tp++ = 0;
tp += add_tlv (tp, 0x7f48, privkey_len);
exthdr_len = tp - exthdr;
/* Build the 5f48 suffix of the data. */
tp = suffix;
tp += add_tlv (tp, 0x5f48, datalen);
suffix_len = tp - suffix;
/* Now concatenate everything. */
template_size = (1 + 1 /* 0x4d and len. */
+ exthdr_len
+ privkey_len
+ suffix_len
+ datalen);
tp = template = xtrymalloc_secure (template_size);
if (!template)
return gpg_error_from_syserror ();
tp += add_tlv (tp, 0x4d, exthdr_len + privkey_len + suffix_len + datalen);
memcpy (tp, exthdr, exthdr_len);
tp += exthdr_len;
memcpy (tp, privkey, privkey_len);
tp += privkey_len;
memcpy (tp, suffix, suffix_len);
tp += suffix_len;
memcpy (tp, ecc_d, ecc_d_len);
tp += ecc_d_len;
assert (tp - template == template_size);
*result = template;
*resultlen = tp - template;
return 0;
}
/* Helper for do_writekley to change the size of a key. Not ethat
this deletes the entire key without asking. */
@ -2749,26 +2863,15 @@ change_keyattr_from_string (app_t app,
}
/* Handle the WRITEKEY command for OpenPGP. This function expects a
canonical encoded S-expression with the secret key in KEYDATA and
its length (for assertions) in KEYDATALEN. KEYID needs to be the
usual keyid which for OpenPGP is the string "OPENPGP.n" with
n=1,2,3. Bit 0 of FLAGS indicates whether an existing key shall
get overwritten. PINCB and PINCB_ARG are the usual arguments for
the pinentry callback. */
static gpg_error_t
do_writekey (app_t app, ctrl_t ctrl,
const char *keyid, unsigned int flags,
gpg_error_t (*pincb)(void*, const char *, char **),
void *pincb_arg,
const unsigned char *keydata, size_t keydatalen)
rsa_writekey (app_t app, gpg_error_t (*pincb)(void*, const char *, char **),
void *pincb_arg, int keyno,
const unsigned char *buf, size_t buflen, int depth)
{
gpg_error_t err;
int force = (flags & 1);
int keyno;
const unsigned char *buf, *tok;
size_t buflen, toklen;
int depth, last_depth1, last_depth2;
const unsigned char *tok;
size_t toklen;
int last_depth1, last_depth2;
const unsigned char *rsa_n = NULL;
const unsigned char *rsa_e = NULL;
const unsigned char *rsa_p = NULL;
@ -2782,52 +2885,6 @@ do_writekey (app_t app, ctrl_t ctrl,
unsigned char fprbuf[20];
u32 created_at = 0;
(void)ctrl;
if (!strcmp (keyid, "OPENPGP.1"))
keyno = 0;
else if (!strcmp (keyid, "OPENPGP.2"))
keyno = 1;
else if (!strcmp (keyid, "OPENPGP.3"))
keyno = 2;
else
return gpg_error (GPG_ERR_INV_ID);
err = does_key_exist (app, keyno, 0, force);
if (err)
return err;
/*
Parse the S-expression
*/
buf = keydata;
buflen = keydatalen;
depth = 0;
if ((err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen)))
goto leave;
if ((err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen)))
goto leave;
if (!tok || toklen != 11 || memcmp ("private-key", tok, toklen))
{
if (!tok)
;
else if (toklen == 21 && !memcmp ("protected-private-key", tok, toklen))
log_info ("protected-private-key passed to writekey\n");
else if (toklen == 20 && !memcmp ("shadowed-private-key", tok, toklen))
log_info ("shadowed-private-key passed to writekey\n");
err = gpg_error (GPG_ERR_BAD_SECKEY);
goto leave;
}
if ((err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen)))
goto leave;
if ((err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen)))
goto leave;
if (!tok || toklen != 3 || memcmp ("rsa", tok, toklen))
{
err = gpg_error (GPG_ERR_WRONG_PUBKEY_ALGO);
goto leave;
}
last_depth1 = depth;
while (!(err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen))
&& depth && depth >= last_depth1)
@ -3100,9 +3157,8 @@ do_writekey (app_t app, ctrl_t ctrl,
goto leave;
}
err = store_fpr (app, keyno, created_at,
rsa_n, rsa_n_len, rsa_e, rsa_e_len,
fprbuf, app->card_version);
err = store_fpr (app, keyno, created_at, fprbuf, app->card_version,
KEY_TYPE_RSA, rsa_n, rsa_n_len, rsa_e, rsa_e_len);
if (err)
goto leave;
@ -3113,6 +3169,279 @@ do_writekey (app_t app, ctrl_t ctrl,
}
static gpg_error_t
ecdh_writekey (app_t app, gpg_error_t (*pincb)(void*, const char *, char **),
void *pincb_arg, int keyno,
const unsigned char *buf, size_t buflen, int depth)
{
return GPG_ERR_NOT_IMPLEMENTED;
}
static gpg_error_t
ecdsa_writekey (app_t app, gpg_error_t (*pincb)(void*, const char *, char **),
void *pincb_arg, int keyno,
const unsigned char *buf, size_t buflen, int depth)
{
gpg_error_t err;
const unsigned char *tok;
size_t toklen;
int last_depth1, last_depth2;
const unsigned char *ecc_q = NULL;
const unsigned char *ecc_d = NULL;
size_t ecc_q_len, ecc_d_len;
unsigned char *template = NULL;
size_t template_len;
unsigned char fprbuf[20];
u32 created_at = 0;
int curve = CURVE_UNKOWN;
/* (private-key(ecdsa(curve%s)(q%m)(d%m))): curve = "1.2.840.10045.3.1.7" */
/* (private-key(ecc(curve%s)(q%m)(d%m))): curve = "secp256k1" */
last_depth1 = depth;
while (!(err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen))
&& depth && depth >= last_depth1)
{
if (tok)
{
err = gpg_error (GPG_ERR_UNKNOWN_SEXP);
goto leave;
}
if ((err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen)))
goto leave;
if (tok && toklen == 5 && !memcmp (tok, "curve", 5))
{
if ((err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen)))
goto leave;
if (tok && toklen == 19 && !memcmp (tok, "1.2.840.10045.3.1.7", 19))
curve = CURVE_NIST_P256;
else if (tok && toklen == 9 && !memcmp (tok, "secp256k1", 9))
curve = CURVE_SEC_P256K1;
}
else if (tok && toklen == 1)
{
const unsigned char **mpi;
size_t *mpi_len;
switch (*tok)
{
case 'q': mpi = &ecc_q; mpi_len = &ecc_q_len; break;
case 'd': mpi = &ecc_d; mpi_len = &ecc_d_len; break;
default: mpi = NULL; mpi_len = NULL; break;
}
if (mpi && *mpi)
{
err = gpg_error (GPG_ERR_DUP_VALUE);
goto leave;
}
if ((err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen)))
goto leave;
if (tok && mpi)
{
/* Strip off leading zero bytes and save. */
for (;toklen && !*tok; toklen--, tok++)
;
*mpi = tok;
*mpi_len = toklen;
}
}
/* Skip until end of list. */
last_depth2 = depth;
while (!(err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen))
&& depth && depth >= last_depth2)
;
if (err)
goto leave;
}
/* Parse other attributes. */
last_depth1 = depth;
while (!(err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen))
&& depth && depth >= last_depth1)
{
if (tok)
{
err = gpg_error (GPG_ERR_UNKNOWN_SEXP);
goto leave;
}
if ((err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen)))
goto leave;
if (tok && toklen == 10 && !memcmp ("created-at", tok, toklen))
{
if ((err = parse_sexp (&buf,&buflen,&depth,&tok,&toklen)))
goto leave;
if (tok)
{
for (created_at=0; toklen && *tok && *tok >= '0' && *tok <= '9';
tok++, toklen--)
created_at = created_at*10 + (*tok - '0');
}
}
/* Skip until end of list. */
last_depth2 = depth;
while (!(err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen))
&& depth && depth >= last_depth2)
;
if (err)
goto leave;
}
/* Check that we have all parameters and that they match the card
description. */
if (!created_at)
{
log_error (_("creation timestamp missing\n"));
err = gpg_error (GPG_ERR_INV_VALUE);
goto leave;
}
if (opt.verbose)
log_info ("ECC private key size is %u bytes\n", (unsigned int)ecc_d_len);
/* We need to remove the cached public key. */
xfree (app->app_local->pk[keyno].key);
app->app_local->pk[keyno].key = NULL;
app->app_local->pk[keyno].keylen = 0;
app->app_local->pk[keyno].read_done = 0;
if (app->app_local->extcap.is_v2)
{
/* Build the private key template as described in section 4.3.3.7 of
the OpenPGP card specs version 2.0. */
int exmode;
err = build_ecdsa_privkey_template (app, keyno,
ecc_d, ecc_d_len,
&template, &template_len);
if (err)
goto leave;
/* Prepare for storing the key. */
err = verify_chv3 (app, pincb, pincb_arg);
if (err)
goto leave;
/* Store the key. */
if (app->app_local->cardcap.ext_lc_le && template_len > 254)
exmode = 1; /* Use extended length w/o a limit. */
else if (app->app_local->cardcap.cmd_chaining && template_len > 254)
exmode = -254;
else
exmode = 0;
err = iso7816_put_data_odd (app->slot, exmode, 0x3fff,
template, template_len);
}
else
return gpg_error (GPG_ERR_NOT_SUPPORTED);
if (err)
{
log_error (_("failed to store the key: %s\n"), gpg_strerror (err));
goto leave;
}
err = store_fpr (app, keyno, created_at, fprbuf, app->card_version,
KEY_TYPE_ECDSA,
curve == CURVE_NIST_P256?
"\x08\x2a\x86\x48\xce\x3d\x03\x01\x07"
: "\05\x2b\x81\x04\x00\x0a",
curve == CURVE_NIST_P256? 9 : 6,
ecc_q, ecc_q_len);
if (err)
goto leave;
leave:
xfree (template);
return err;
}
/* Handle the WRITEKEY command for OpenPGP. This function expects a
canonical encoded S-expression with the secret key in KEYDATA and
its length (for assertions) in KEYDATALEN. KEYID needs to be the
usual keyid which for OpenPGP is the string "OPENPGP.n" with
n=1,2,3. Bit 0 of FLAGS indicates whether an existing key shall
get overwritten. PINCB and PINCB_ARG are the usual arguments for
the pinentry callback. */
static gpg_error_t
do_writekey (app_t app, ctrl_t ctrl,
const char *keyid, unsigned int flags,
gpg_error_t (*pincb)(void*, const char *, char **),
void *pincb_arg,
const unsigned char *keydata, size_t keydatalen)
{
gpg_error_t err;
int force = (flags & 1);
int keyno;
const unsigned char *buf, *tok;
size_t buflen, toklen;
int depth;
(void)ctrl;
if (!strcmp (keyid, "OPENPGP.1"))
keyno = 0;
else if (!strcmp (keyid, "OPENPGP.2"))
keyno = 1;
else if (!strcmp (keyid, "OPENPGP.3"))
keyno = 2;
else
return gpg_error (GPG_ERR_INV_ID);
err = does_key_exist (app, keyno, 0, force);
if (err)
return err;
/*
Parse the S-expression
*/
buf = keydata;
buflen = keydatalen;
depth = 0;
if ((err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen)))
goto leave;
if ((err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen)))
goto leave;
if (!tok || toklen != 11 || memcmp ("private-key", tok, toklen))
{
if (!tok)
;
else if (toklen == 21 && !memcmp ("protected-private-key", tok, toklen))
log_info ("protected-private-key passed to writekey\n");
else if (toklen == 20 && !memcmp ("shadowed-private-key", tok, toklen))
log_info ("shadowed-private-key passed to writekey\n");
err = gpg_error (GPG_ERR_BAD_SECKEY);
goto leave;
}
if ((err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen)))
goto leave;
if ((err = parse_sexp (&buf, &buflen, &depth, &tok, &toklen)))
goto leave;
if (tok && toklen == 3 && memcmp ("rsa", tok, toklen) == 0)
rsa_writekey (app, pincb, pincb_arg, keyno, buf, buflen, depth);
else if ((tok && toklen == 3 && memcmp ("ecc", tok, toklen) == 0
&& (keyno == 0 || keyno == 2))
|| (tok && toklen == 5 && memcmp ("ecdsa", tok, toklen) == 0))
ecdsa_writekey (app, pincb, pincb_arg, keyno, buf, buflen, depth);
else if ((tok && toklen == 3 && memcmp ("ecc", tok, toklen) == 0
&& keyno == 1)
|| (tok && toklen == 4 && memcmp ("ecdh", tok, toklen) == 0))
ecdh_writekey (app, pincb, pincb_arg, keyno, buf, buflen, depth);
else
{
err = gpg_error (GPG_ERR_WRONG_PUBKEY_ALGO);
goto leave;
}
leave:
return err;
}
/* Handle the GENKEY command. */
static gpg_error_t
do_genkey (app_t app, ctrl_t ctrl, const char *keynostr, unsigned int flags,
@ -3234,8 +3563,8 @@ do_genkey (app_t app, ctrl_t ctrl, const char *keynostr, unsigned int flags,
send_status_info (ctrl, "KEY-CREATED-AT",
numbuf, (size_t)strlen(numbuf), NULL, 0);
rc = store_fpr (app, keyno, (u32)created_at,
m, mlen, e, elen, fprbuf, app->card_version);
rc = store_fpr (app, keyno, (u32)created_at, fprbuf, app->card_version,
KEY_TYPE_RSA, m, mlen, e, elen);
if (rc)
goto leave;
send_fpr_if_not_null (ctrl, "KEY-FPR", -1, fprbuf);
@ -3973,8 +4302,10 @@ parse_ecc_curve (const unsigned char *buffer, size_t buflen)
curve = CURVE_NIST_P384;
else if (buflen == 6 && buffer[5] == 0x23)
curve = CURVE_NIST_P521;
else
else if (buflen == 9)
curve = CURVE_NIST_P256;
else
curve = CURVE_SEC_P256K1;
return curve;
}