2005-02-19 Moritz Schulte <moritz@g10code.com>

* command-ssh.c (ssh_receive_mpint_list): Slightly rewritten, do
	not use elems_secret member of key_spec.
	(ssh_key_type_spec): Removed member: elems_secret.
	(ssh_key_types): Removed elems_secret data.
	(ssh_sexp_construct): Renamed to ...
	(sexp_key_construct): ... this; changed callers.
	(ssh_sexp_extract): Renamed to ...
	(sexp_key_extract): ... this; changed callers.
	(ssh_sexp_extract_key_type): Renamed to ...
	(sexp_extract_identifier): ... this; changed callers; use
	make_cstring().
	Added more comments.
This commit is contained in:
Moritz Schulte 2005-02-19 17:17:30 +00:00
parent cd42f5e45f
commit 823eaefb0b
2 changed files with 93 additions and 39 deletions

View File

@ -1,3 +1,18 @@
2005-02-19 Moritz Schulte <moritz@g10code.com>
* command-ssh.c (ssh_receive_mpint_list): Slightly rewritten, do
not use elems_secret member of key_spec.
(ssh_key_type_spec): Removed member: elems_secret.
(ssh_key_types): Removed elems_secret data.
(ssh_sexp_construct): Renamed to ...
(sexp_key_construct): ... this; changed callers.
(ssh_sexp_extract): Renamed to ...
(sexp_key_extract): ... this; changed callers.
(ssh_sexp_extract_key_type): Renamed to ...
(sexp_extract_identifier): ... this; changed callers; use
make_cstring().
Added more comments.
2005-02-18 Moritz Schulte <moritz@g10code.com>
* command-ssh.c (ssh_sexp_construct): Rewritten generation of sexp

View File

@ -75,12 +75,17 @@
/* Basic types. */
/*
* Basic types.
*/
/* Type for a request handler. */
typedef gpg_error_t (*ssh_request_handler_t) (ctrl_t ctrl,
estream_t request,
estream_t response);
/* Type, which is used for associating request handlers with the
appropriate request IDs. */
typedef struct ssh_request_spec
{
unsigned char type;
@ -88,22 +93,51 @@ typedef struct ssh_request_spec
const char *identifier;
} ssh_request_spec_t;
/* Type for "key modifier functions", which are necessary since
OpenSSH and GnuPG treat key material slightly different. A key
modifier is called right after a new key identity has been received
in order to "sanitize" the material. */
typedef gpg_error_t (*ssh_key_modifier_t) (const char *elems,
gcry_mpi_t *mpis);
/* The encoding of a generated signature is dependent on the
algorithm; therefore algorithm specific signature encoding
functions are necessary. */
typedef gpg_error_t (*ssh_signature_encoder_t) (estream_t signature_blob,
gcry_mpi_t *mpis);
/* Type, which is used for boundling all the algorithm specific
information together in a single object. */
typedef struct ssh_key_type_spec
{
/* Algorithm identifier as used by OpenSSH. */
const char *ssh_identifier;
/* Algorithm identifier as used by GnuPG. */
const char *identifier;
/* List of MPI names for secret keys; order matches the one of the
agent protocol. */
const char *elems_key_secret;
/* List of MPI names for public keys; order matches the one of the
agent protocol. */
const char *elems_key_public;
const char *elems_secret;
/* List of MPI names for signature data. */
const char *elems_signature;
/* List of MPI names for secret keys; order matches the one, which
is required by gpg-agent's key access layer. */
const char *elems_sexp_order;
/* Key modifier function. */
ssh_key_modifier_t key_modifier;
/* Signature encoder function. */
ssh_signature_encoder_t signature_encoder;
/* Misc flags. */
unsigned int flags;
} ssh_key_type_spec_t;
@ -166,12 +200,12 @@ static ssh_request_spec_t request_specs[] =
static ssh_key_type_spec_t ssh_key_types[] =
{
{
"ssh-rsa", "rsa", "nedupq", "en", "dupq", "s", "nedpqu",
"ssh-rsa", "rsa", "nedupq", "en", "s", "nedpqu",
ssh_key_modifier_rsa, ssh_signature_encoder_rsa,
SPEC_FLAG_USE_PKCS1V2
},
{
"ssh-dss", "dsa", "pqgyx", "pqgy", "x", "rs", "pqgyx",
"ssh-dss", "dsa", "pqgyx", "pqgy", "rs", "pqgyx",
NULL, ssh_signature_encoder_dsa,
0
},
@ -206,7 +240,8 @@ realloc_secure (void *a, size_t n)
}
/* Create and return a new C-string from DATA/DATA_N (i.e.: add
NUL-termination); return NULL on OOM. */
static char *
make_cstring (const char *data, size_t data_n)
{
@ -604,6 +639,7 @@ file_to_buffer (const char *filename, unsigned char **buffer, size_t *buffer_n)
*/
/* Free the list of MPIs MPI_LIST. */
static void
mpint_list_free (gcry_mpi_t *mpi_list)
{
@ -622,29 +658,27 @@ static gpg_error_t
ssh_receive_mpint_list (estream_t stream, int secret,
ssh_key_type_spec_t key_spec, gcry_mpi_t **mpi_list)
{
const char *elems_secret;
const char *elems;
unsigned int elems_public_n;
const char *elems_public;
unsigned int elems_n;
gcry_mpi_t *mpis;
unsigned int i;
gpg_error_t err;
const char *elems;
int elem_is_secret;
gcry_mpi_t *mpis;
gpg_error_t err;
unsigned int i;
mpis = NULL;
err = 0;
if (secret)
{
elems = key_spec.elems_key_secret;
elems_secret = key_spec.elems_secret;
}
elems = key_spec.elems_key_secret;
else
{
elems = key_spec.elems_key_public;
elems_secret = "";
}
elems = key_spec.elems_key_public;
elems_n = strlen (elems);
elems_public = key_spec.elems_key_public;
elems_public_n = strlen (elems_public);
mpis = xtrymalloc (sizeof (*mpis) * (elems_n + 1));
if (! mpis)
{
@ -653,10 +687,12 @@ ssh_receive_mpint_list (estream_t stream, int secret,
}
memset (mpis, 0, sizeof (*mpis) * (elems_n + 1));
elem_is_secret = 0;
for (i = 0; i < elems_n; i++)
{
elem_is_secret = strchr (elems_secret, elems[i]) ? 1 : 0;
if (secret)
elem_is_secret = ! strchr (elems_public, elems[i]);
err = stream_read_mpi (stream, elem_is_secret, &mpis[i]);
if (err)
break;
@ -676,6 +712,7 @@ ssh_receive_mpint_list (estream_t stream, int secret,
/* Key modifier function for RSA. */
static gpg_error_t
ssh_key_modifier_rsa (const char *elems, gcry_mpi_t *mpis)
{
@ -709,6 +746,7 @@ ssh_key_modifier_rsa (const char *elems, gcry_mpi_t *mpis)
return 0;
}
/* Signature encoder function for RSA. */
static gpg_error_t
ssh_signature_encoder_rsa (estream_t signature_blob, gcry_mpi_t *mpis)
{
@ -732,7 +770,7 @@ ssh_signature_encoder_rsa (estream_t signature_blob, gcry_mpi_t *mpis)
}
/* Signature encoder function for DSA. */
static gpg_error_t
ssh_signature_encoder_dsa (estream_t signature_blob, gcry_mpi_t *mpis)
{
@ -781,9 +819,9 @@ ssh_signature_encoder_dsa (estream_t signature_blob, gcry_mpi_t *mpis)
*/
/* */
static gpg_error_t
ssh_sexp_construct (gcry_sexp_t *sexp,
sexp_key_construct (gcry_sexp_t *sexp,
ssh_key_type_spec_t key_spec, int secret,
gcry_mpi_t *mpis, const char *comment)
{
@ -871,8 +909,9 @@ ssh_sexp_construct (gcry_sexp_t *sexp,
return err;
}
static gpg_error_t
ssh_sexp_extract (gcry_sexp_t sexp,
sexp_key_extract (gcry_sexp_t sexp,
ssh_key_type_spec_t key_spec, int *secret,
gcry_mpi_t **mpis, const char **comment)
{
@ -1002,17 +1041,19 @@ ssh_sexp_extract (gcry_sexp_t sexp,
return err;
}
/* Extract the car from SEXP, and create a newly created C-string it,
which is to be stored in IDENTIFIER. */
static gpg_error_t
ssh_sexp_extract_key_type (gcry_sexp_t sexp, const char **key_type)
sexp_extract_identifier (gcry_sexp_t sexp, const char **identifier)
{
char *identifier_new;
gcry_sexp_t sublist;
char *key_type_new;
const char *data;
size_t data_n;
gpg_error_t err;
identifier_new = NULL;
err = 0;
key_type_new = NULL;
sublist = gcry_sexp_nth (sexp, 1);
if (! sublist)
@ -1028,16 +1069,14 @@ ssh_sexp_extract_key_type (gcry_sexp_t sexp, const char **key_type)
goto out;
}
key_type_new = xtrymalloc (data_n + 1);
if (! key_type_new)
identifier_new = make_cstring (data, data_n);
if (! identifier_new)
{
err = gpg_error_from_errno (errno);
err = gpg_err_code_from_errno (errno);
goto out;
}
strncpy (key_type_new, data, data_n);
key_type_new[data_n] = 0;
*key_type = key_type_new;
*identifier = identifier_new;
out:
@ -1121,7 +1160,7 @@ ssh_receive_key (estream_t stream, gcry_sexp_t *key_new, int secret,
goto out;
}
err = ssh_sexp_construct (&key, spec, secret, mpi_list, comment);
err = sexp_key_construct (&key, spec, secret, mpi_list, comment);
if (err)
goto out;
@ -1221,7 +1260,7 @@ ssh_send_key_public (estream_t stream, gcry_sexp_t key_public)
comment = NULL;
blob = NULL;
err = ssh_sexp_extract_key_type (key_public, &key_type);
err = sexp_extract_identifier (key_public, &key_type);
if (err)
goto out;
@ -1229,7 +1268,7 @@ ssh_send_key_public (estream_t stream, gcry_sexp_t key_public)
if (err)
goto out;
err = ssh_sexp_extract (key_public, spec, NULL, &mpi_list, &comment);
err = sexp_key_extract (key_public, spec, NULL, &mpi_list, &comment);
if (err)
goto out;
@ -1303,11 +1342,11 @@ key_secret_to_public (gcry_sexp_t *key_public,
comment = NULL;
mpis = NULL;
err = ssh_sexp_extract (key_secret, spec, &is_secret, &mpis, &comment);
err = sexp_key_extract (key_secret, spec, &is_secret, &mpis, &comment);
if (err)
goto out;
err = ssh_sexp_construct (key_public, spec, 0, mpis, comment);
err = sexp_key_construct (key_public, spec, 0, mpis, comment);
out:
@ -1415,7 +1454,7 @@ ssh_handler_request_identities (ctrl_t ctrl,
xfree (buffer);
buffer = NULL;
err = ssh_sexp_extract_key_type (key_secret, &key_type);
err = sexp_extract_identifier (key_secret, &key_type);
if (err)
break;