agent: Fix agent_public_key_from_file for ECC.

* agent/cvt-openpgp.c (extract_private_key): New.
(convert_to_openpgp): Use extract_private_key.
* agent/findkey.c (agent_public_key_from_file): Use
extract_private_key.

--

This patch add support of ECC key with a curve name and flags.  Since
same functionality is also needed for convert_to_openpgp, it was
factored out into the extract_private_key function.
This commit is contained in:
NIIBE Yutaka 2015-01-27 09:30:11 +09:00
parent 6c87d1ce66
commit 9453d645d4
3 changed files with 151 additions and 94 deletions

View File

@ -497,4 +497,11 @@ int agent_card_scd (ctrl_t ctrl, const char *cmdline,
int agent_handle_learn (ctrl_t ctrl, int send, void *assuan_context);
/*-- cvt-openpgp.c --*/
gpg_error_t
extract_private_key (gcry_sexp_t s_key, int req_private_key_data,
const char **r_algoname, int *r_npkey, int *r_nskey,
const char **r_format, gcry_mpi_t *mpi_array,
gcry_sexp_t *r_curve, gcry_sexp_t *r_flags);
#endif /*AGENT_H*/

View File

@ -1177,36 +1177,50 @@ apply_protection (gcry_mpi_t *array, int npkey, int nskey,
}
/* Convert our key S_KEY into an OpenPGP key transfer format. On
success a canonical encoded S-expression is stored at R_TRANSFERKEY
and its length at R_TRANSFERKEYLEN; this S-expression is also
padded to a multiple of 64 bits. */
/*
* Examining S_KEY in S-Expression and extract data.
* When REQ_PRIVATE_KEY_DATA == 1, S_KEY's CAR should be 'private-key',
* but it also allows shadowed or protected versions.
* On success, it returns 0, otherwise error number.
* R_ALGONAME is static string which is no need to free by caller.
* R_NPKEY is pointer to number of public key data.
* R_NSKEY is pointer to number of private key data.
* R_ELEMS is static string which is no need to free by caller.
* ARRAY contains public and private key data.
* R_CURVE is pointer to S-Expression of the curve (can be NULL).
* R_FLAGS is pointer to S-Expression of the flags (can be NULL).
*/
gpg_error_t
convert_to_openpgp (ctrl_t ctrl, gcry_sexp_t s_key, const char *passphrase,
unsigned char **r_transferkey, size_t *r_transferkeylen)
extract_private_key (gcry_sexp_t s_key, int req_private_key_data,
const char **r_algoname, int *r_npkey, int *r_nskey,
const char **r_elems, gcry_mpi_t *array,
gcry_sexp_t *r_curve, gcry_sexp_t *r_flags)
{
gpg_error_t err;
gcry_sexp_t list, l2;
char *name;
const char *algoname;
const char *algoname, *format;
int npkey, nskey;
gcry_mpi_t array[10];
gcry_sexp_t curve = NULL;
char protect_iv[16];
char salt[8];
unsigned long s2k_count;
int i, j;
gcry_sexp_t flags = NULL;
(void)ctrl;
if (!req_private_key_data)
{
list = gcry_sexp_find_token (s_key, "shadowed-private-key", 0 );
if (!list)
list = gcry_sexp_find_token (s_key, "protected-private-key", 0 );
if (!list)
list = gcry_sexp_find_token (s_key, "private-key", 0 );
}
else
list = gcry_sexp_find_token (s_key, "private-key", 0);
*r_transferkey = NULL;
for (i=0; i < DIM (array); i++)
array[i] = NULL;
list = gcry_sexp_find_token (s_key, "private-key", 0);
if (!list)
return gpg_error (GPG_ERR_NO_OBJ); /* Does not contain a key object. */
{
log_error ("invalid private key format\n");
return gpg_error (GPG_ERR_BAD_SECKEY);
}
l2 = gcry_sexp_cadr (list);
gcry_sexp_release (list);
list = l2;
@ -1224,66 +1238,81 @@ convert_to_openpgp (ctrl_t ctrl, gcry_sexp_t s_key, const char *passphrase,
if (!strcmp (name, "rsa"))
{
algoname = "rsa";
format = "ned?p?q?u?";
npkey = 2;
nskey = 6;
err = gcry_sexp_extract_param (list, NULL, "nedpqu",
err = gcry_sexp_extract_param (list, NULL, format,
array+0, array+1, array+2, array+3,
array+4, array+5, NULL);
}
else if (!strcmp (name, "elg"))
{
algoname = "elg";
format = "pgyx?";
npkey = 3;
nskey = 4;
err = gcry_sexp_extract_param (list, NULL, "pgyx",
err = gcry_sexp_extract_param (list, NULL, format,
array+0, array+1, array+2, array+3,
NULL);
}
else if (!strcmp (name, "dsa"))
{
algoname = "dsa";
format = "pqgyx?";
npkey = 4;
nskey = 5;
err = gcry_sexp_extract_param (list, NULL, "pqgyx",
err = gcry_sexp_extract_param (list, NULL, format,
array+0, array+1, array+2, array+3,
array+4, NULL);
}
else if (!strcmp (name, "ecc"))
{
gcry_buffer_t iob;
char iobbuf[32];
algoname = "ecc"; /* Decide later by checking the usage. */
algoname = "ecc";
format = "/qd?";
npkey = 1;
nskey = 2;
iob.data = iobbuf;
iob.size = sizeof iobbuf - 1;
iob.off = 0;
iob.len = 0;
err = gcry_sexp_extract_param (list, NULL, "&'curve'/qd",
&iob, array+0, array+1, NULL);
if (!err)
curve = gcry_sexp_find_token (list, "curve", 0);
flags = gcry_sexp_find_token (list, "flags", 0);
err = gcry_sexp_extract_param (list, NULL, format,
array+0, array+1, NULL);
if (flags)
{
assert (iob.len < sizeof iobbuf -1);
iobbuf[iob.len] = 0;
err = gcry_sexp_build (&curve, NULL, "(curve %s)", iobbuf);
gcry_sexp_t param = gcry_sexp_find_token (flags, "param", 0);
if (param)
{
gcry_sexp_release (param);
array[6] = array[0];
array[7] = array[1];
err = gcry_sexp_extract_param (list, NULL, "pabgnh?",
array+0, array+1, array+2, array+3,
array+4, array+5, NULL);
if (array[5] == NULL)
{
array[5] = GCRYMPI_CONST_ONE;
npkey += 6;
nskey += 6;
}
format = "pabgnhqd?";
}
}
}
else if (!strcmp (name, "ecdsa"))
{
algoname = "ecdsa";
format = "pabgnqd?";
npkey = 6;
nskey = 7;
err = gcry_sexp_extract_param (list, NULL, "pabgnqd",
err = gcry_sexp_extract_param (list, NULL, format,
array+0, array+1, array+2, array+3,
array+4, array+5, array+6, NULL);
}
else if (!strcmp (name, "ecdh"))
{
algoname = "ecdh";
format = "pabgnqd?";
npkey = 6;
nskey= 7;
err = gcry_sexp_extract_param (list, NULL, "pabgnqd",
err = gcry_sexp_extract_param (list, NULL, format,
array+0, array+1, array+2, array+3,
array+4, array+5, array+6, NULL);
}
@ -1292,12 +1321,63 @@ convert_to_openpgp (ctrl_t ctrl, gcry_sexp_t s_key, const char *passphrase,
err = gpg_error (GPG_ERR_PUBKEY_ALGO);
}
xfree (name);
gcry_sexp_release (list); list = NULL;
gcry_sexp_release (list);
if (err)
{
gcry_sexp_release (curve);
gcry_sexp_release (flags);
return err;
}
else
{
*r_algoname = algoname;
if (r_elems)
{
if (format[0] == '/') /* It is opaque data qualifier, skip it. */
*r_elems = format+1;
else
*r_elems = format;
}
*r_npkey = npkey;
if (r_nskey)
*r_nskey = nskey;
*r_curve = curve;
*r_flags = flags;
return 0;
}
}
/* Convert our key S_KEY into an OpenPGP key transfer format. On
success a canonical encoded S-expression is stored at R_TRANSFERKEY
and its length at R_TRANSFERKEYLEN; this S-expression is also
padded to a multiple of 64 bits. */
gpg_error_t
convert_to_openpgp (ctrl_t ctrl, gcry_sexp_t s_key, const char *passphrase,
unsigned char **r_transferkey, size_t *r_transferkeylen)
{
gpg_error_t err;
const char *algoname;
int npkey, nskey;
gcry_mpi_t array[10];
gcry_sexp_t curve = NULL;
gcry_sexp_t flags = NULL;
char protect_iv[16];
char salt[8];
unsigned long s2k_count;
int i, j;
(void)ctrl;
*r_transferkey = NULL;
for (i=0; i < DIM (array); i++)
array[i] = NULL;
err = extract_private_key (s_key, 1, &algoname, &npkey, &nskey, NULL,
array, &curve, &flags);
if (err)
return err;
gcry_create_nonce (protect_iv, sizeof protect_iv);
gcry_create_nonce (salt, sizeof salt);
@ -1363,6 +1443,7 @@ convert_to_openpgp (ctrl_t ctrl, gcry_sexp_t s_key, const char *passphrase,
for (i=0; i < DIM (array); i++)
gcry_mpi_release (array[i]);
gcry_sexp_release (curve);
gcry_sexp_release (flags);
return err;
}

View File

@ -978,18 +978,20 @@ agent_public_key_from_file (ctrl_t ctrl,
gpg_error_t err;
int i, idx;
gcry_sexp_t s_skey;
char algoname[6];
char elems[7];
const char *algoname, *elems;
int npkey;
gcry_mpi_t array[10];
gcry_sexp_t curve = NULL;
gcry_sexp_t flags = NULL;
gcry_sexp_t uri_sexp, comment_sexp;
const char *uri, *comment;
size_t uri_length, comment_length;
char *format, *p;
void *args[4+2+2+1]; /* Size is max. # of elements + 2 for uri + 2
for comment + end-of-list. */
void *args[2+7+2+2+1]; /* Size is 2 + max. # of elements + 2 for uri + 2
for comment + end-of-list. */
int argidx;
gcry_sexp_t list, l2;
gcry_sexp_t list = NULL;
const char *s;
gcry_mpi_t *array;
(void)ctrl;
@ -999,55 +1001,17 @@ agent_public_key_from_file (ctrl_t ctrl,
if (err)
return err;
err = key_parms_from_sexp (s_skey, &list,
algoname, sizeof algoname,
elems, sizeof elems);
for (i=0; i < DIM (array); i++)
array[i] = NULL;
err = extract_private_key (s_skey, 0, &algoname, &npkey, NULL, &elems,
array, &curve, &flags);
if (err)
{
gcry_sexp_release (s_skey);
return err;
}
/* Allocate an array for the parameters and copy them out of the
secret key. FIXME: We should have a generic copy function. */
array = xtrycalloc (strlen(elems) + 1, sizeof *array);
if (!array)
{
err = gpg_error_from_syserror ();
gcry_sexp_release (list);
gcry_sexp_release (s_skey);
return err;
}
for (idx=0, s=elems; *s; s++, idx++ )
{
l2 = gcry_sexp_find_token (list, s, 1);
if (!l2)
{
/* Required parameter not found. */
for (i=0; i<idx; i++)
gcry_mpi_release (array[i]);
xfree (array);
gcry_sexp_release (list);
gcry_sexp_release (s_skey);
return gpg_error (GPG_ERR_BAD_SECKEY);
}
array[idx] = gcry_sexp_nth_mpi (l2, 1, GCRYMPI_FMT_USG);
gcry_sexp_release (l2);
if (!array[idx])
{
/* Required parameter is invalid. */
for (i=0; i<idx; i++)
gcry_mpi_release (array[i]);
xfree (array);
gcry_sexp_release (list);
gcry_sexp_release (s_skey);
return gpg_error (GPG_ERR_BAD_SECKEY);
}
}
gcry_sexp_release (list);
list = NULL;
uri = NULL;
uri_length = 0;
uri_sexp = gcry_sexp_find_token (s_skey, "uri", 0);
@ -1072,13 +1036,14 @@ agent_public_key_from_file (ctrl_t ctrl,
them. */
assert (sizeof (size_t) <= sizeof (void*));
format = xtrymalloc (15+7*strlen (elems)+10+15+1+1);
format = xtrymalloc (15+4+7*npkey+10+15+1+1);
if (!format)
{
err = gpg_error_from_syserror ();
for (i=0; array[i]; i++)
gcry_mpi_release (array[i]);
xfree (array);
gcry_sexp_release (curve);
gcry_sexp_release (flags);
gcry_sexp_release (uri_sexp);
gcry_sexp_release (comment_sexp);
return err;
@ -1086,10 +1051,13 @@ agent_public_key_from_file (ctrl_t ctrl,
argidx = 0;
p = stpcpy (stpcpy (format, "(public-key("), algoname);
for (idx=0, s=elems; *s; s++, idx++ )
p = stpcpy (p, "%S%S"); /* curve name and flags. */
args[argidx++] = &curve;
args[argidx++] = &flags;
for (idx=0, s=elems; idx < npkey; idx++)
{
*p++ = '(';
*p++ = *s;
*p++ = *s++;
p = stpcpy (p, " %m)");
assert (argidx < DIM (args));
args[argidx++] = &array[idx];
@ -1118,7 +1086,8 @@ agent_public_key_from_file (ctrl_t ctrl,
xfree (format);
for (i=0; array[i]; i++)
gcry_mpi_release (array[i]);
xfree (array);
gcry_sexp_release (curve);
gcry_sexp_release (flags);
gcry_sexp_release (uri_sexp);
gcry_sexp_release (comment_sexp);