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Diffstat (limited to 'scd/app-openpgp.c')
-rw-r--r--scd/app-openpgp.c192
1 files changed, 111 insertions, 81 deletions
diff --git a/scd/app-openpgp.c b/scd/app-openpgp.c
index 6e4aa5808..89bea7220 100644
--- a/scd/app-openpgp.c
+++ b/scd/app-openpgp.c
@@ -355,7 +355,6 @@ do_deinit (app_t app)
* we do not need this if the buffer has been allocated in secure
* memory. However at some places we can't make that sure and thus we
* better to an extra wipe here. */
-#if 0 /* Not yet used. */
static void
wipe_and_free (void *p, size_t len)
{
@@ -366,11 +365,10 @@ wipe_and_free (void *p, size_t len)
xfree (p);
}
}
-#endif
+
/* Similar to wipe_and_free but assumes P is eitehr NULL or a proper
* string. */
-#if 0 /* Not yet used. */
static void
wipe_and_free_string (char *p)
{
@@ -380,7 +378,7 @@ wipe_and_free_string (char *p)
xfree (p);
}
}
-#endif
+
/* Wrapper around iso7816_get_data which first tries to get the data
from the cache. With GET_IMMEDIATE passed as true, the cache is
@@ -2484,26 +2482,41 @@ get_prompt_info (app_t app, int chvno, unsigned long sigcount, int remaining)
return result;
}
+
/* Compute hash if KDF-DO is available. CHVNO must be 0 for reset
- code, 1 or 2 for user pin and 3 for admin pin.
- */
+ * code, 1 or 2 for user pin and 3 for admin pin. PIN is the original
+ * PIN as entered by the user. R_PINVALUE and r_PINLEN will receive a
+ * newly allocated buffer with a possible modified pin. */
static gpg_error_t
-pin2hash_if_kdf (app_t app, int chvno, char *pinvalue, int *r_pinlen)
+pin2hash_if_kdf (app_t app, int chvno, const char *pin,
+ char **r_pinvalue, size_t *r_pinlen)
{
gpg_error_t err = 0;
void *relptr = NULL;
unsigned char *buffer;
- size_t buflen;
+ size_t pinlen, buflen;
+ char *dek = NULL;
+ size_t deklen = 32;
+ *r_pinvalue = NULL;
+ *r_pinlen = 0;
+
+ pinlen = strlen (pin);
if (app->app_local->extcap.kdf_do
&& (relptr = get_one_do (app, 0x00F9, &buffer, &buflen, NULL))
&& buflen >= KDF_DATA_LENGTH_MIN && (buffer[2] == 0x03))
{
const char *salt;
unsigned long s2k_count;
- char dek[32];
int salt_index;
+ dek = xtrymalloc (deklen);
+ if (!dek)
+ {
+ err = gpg_error_from_syserror ();
+ goto leave;
+ }
+
s2k_count = (((unsigned int)buffer[8] << 24)
| (buffer[9] << 16) | (buffer[10] << 8) | buffer[11]);
@@ -2518,20 +2531,29 @@ pin2hash_if_kdf (app_t app, int chvno, char *pinvalue, int *r_pinlen)
}
salt = &buffer[salt_index];
- err = gcry_kdf_derive (pinvalue, strlen (pinvalue),
+ err = gcry_kdf_derive (pin, pinlen,
GCRY_KDF_ITERSALTED_S2K,
DIGEST_ALGO_SHA256, salt, 8,
s2k_count, sizeof (dek), dek);
if (!err)
{
- /* pinvalue has a buffer of MAXLEN_PIN+1, 32 is OK. */
- *r_pinlen = 32;
- memcpy (pinvalue, dek, *r_pinlen);
- wipememory (dek, *r_pinlen);
+ *r_pinlen = deklen;
+ *r_pinvalue = dek;
+ dek = NULL;
}
}
else
- *r_pinlen = strlen (pinvalue);
+ {
+ /* Just copy the PIN to a malloced buffer. */
+ *r_pinvalue = xtrymalloc_secure (pinlen + 1);
+ if (!*r_pinvalue)
+ {
+ err = gpg_error_from_syserror ();
+ goto leave;
+ }
+ strcpy (*r_pinvalue, pin);
+ *r_pinlen = pinlen;
+ }
leave:
xfree (relptr);
@@ -2553,7 +2575,7 @@ static gpg_error_t
verify_a_chv (app_t app, ctrl_t ctrl,
gpg_error_t (*pincb)(void*, const char *, char **),
void *pincb_arg, int chvno, unsigned long sigcount,
- char **pinvalue, int *pinlen)
+ char **r_pinvalue, size_t *r_pinlen)
{
int rc = 0;
char *prompt_buffer = NULL;
@@ -2561,13 +2583,14 @@ verify_a_chv (app_t app, ctrl_t ctrl,
pininfo_t pininfo;
int minlen = 6;
int remaining;
+ char *pin = NULL;
(void)ctrl; /* Reserved for use by a PIN cache. */
log_assert (chvno == 1 || chvno == 2);
- *pinvalue = NULL;
- *pinlen = 0;
+ *r_pinvalue = NULL;
+ *r_pinlen = 0;
remaining = get_remaining_tries (app, 0);
if (remaining == -1)
@@ -2630,13 +2653,11 @@ verify_a_chv (app_t app, ctrl_t ctrl,
rc = iso7816_verify_kp (app_get_slot (app), 0x80+chvno, &pininfo);
/* Dismiss the prompt. */
pincb (pincb_arg, NULL, NULL);
-
- log_assert (!*pinvalue);
}
else
{
/* The reader has no pinpad or we don't want to use it. */
- rc = pincb (pincb_arg, prompt, pinvalue);
+ rc = pincb (pincb_arg, prompt, &pin);
prompt = NULL;
xfree (prompt_buffer);
prompt_buffer = NULL;
@@ -2647,26 +2668,27 @@ verify_a_chv (app_t app, ctrl_t ctrl,
return rc;
}
- if (strlen (*pinvalue) < minlen)
+ if (strlen (pin) < minlen)
{
log_error (_("PIN for CHV%d is too short;"
" minimum length is %d\n"), chvno, minlen);
- xfree (*pinvalue);
- *pinvalue = NULL;
+ wipe_and_free_string (pin);
return gpg_error (GPG_ERR_BAD_PIN);
}
- rc = pin2hash_if_kdf (app, chvno, *pinvalue, pinlen);
+ rc = pin2hash_if_kdf (app, chvno, pin, r_pinvalue, r_pinlen);
if (!rc)
rc = iso7816_verify (app_get_slot (app),
- 0x80 + chvno, *pinvalue, *pinlen);
+ 0x80 + chvno, *r_pinvalue, *r_pinlen);
}
+ wipe_and_free_string (pin);
if (rc)
{
log_error (_("verify CHV%d failed: %s\n"), chvno, gpg_strerror (rc));
- xfree (*pinvalue);
- *pinvalue = NULL;
+ xfree (*r_pinvalue);
+ *r_pinvalue = NULL;
+ *r_pinlen = 0;
flush_cache_after_error (app);
}
@@ -2683,7 +2705,7 @@ verify_chv2 (app_t app, ctrl_t ctrl,
{
int rc;
char *pinvalue;
- int pinlen;
+ size_t pinlen;
int i;
if (app->did_chv2)
@@ -2730,7 +2752,7 @@ verify_chv2 (app_t app, ctrl_t ctrl,
return rc;
}
- xfree (pinvalue);
+ wipe_and_free (pinvalue, pinlen);
return rc;
}
@@ -2828,10 +2850,11 @@ verify_chv3 (app_t app, ctrl_t ctrl,
}
else
{
+ char *pin;
char *pinvalue;
- int pinlen;
+ size_t pinlen;
- rc = pincb (pincb_arg, prompt, &pinvalue);
+ rc = pincb (pincb_arg, prompt, &pin);
xfree (prompt);
prompt = NULL;
if (rc)
@@ -2841,18 +2864,19 @@ verify_chv3 (app_t app, ctrl_t ctrl,
return rc;
}
- if (strlen (pinvalue) < minlen)
+ if (strlen (pin) < minlen)
{
log_error (_("PIN for CHV%d is too short;"
" minimum length is %d\n"), 3, minlen);
- xfree (pinvalue);
+ wipe_and_free_string (pin);
return gpg_error (GPG_ERR_BAD_PIN);
}
- rc = pin2hash_if_kdf (app, 3, pinvalue, &pinlen);
+ rc = pin2hash_if_kdf (app, 3, pin, &pinvalue, &pinlen);
if (!rc)
rc = iso7816_verify (app_get_slot (app), 0x83, pinvalue, pinlen);
- xfree (pinvalue);
+ wipe_and_free_string (pin);
+ wipe_and_free (pinvalue, pinlen);
}
if (rc)
@@ -3066,8 +3090,6 @@ do_change_pin (app_t app, ctrl_t ctrl, const char *chvnostr,
pininfo_t pininfo;
int use_pinpad = 0;
int minlen = 6;
- int pinlen0 = 0;
- int pinlen = 0;
if (digitp (chvnostr))
chvno = atoi (chvnostr);
@@ -3269,51 +3291,65 @@ do_change_pin (app_t app, ctrl_t ctrl, const char *chvnostr,
if (resetcode)
{
- char *buffer;
+ char *result1 = NULL;
+ char *result2 = NULL;
+ char *buffer = NULL;
+ size_t resultlen1=0, resultlen2=0, bufferlen=0;
- buffer = xtrymalloc (strlen (resetcode) + strlen (pinvalue) + 1);
- if (!buffer)
- rc = gpg_error_from_syserror ();
- else
+ rc = pin2hash_if_kdf (app, 0, resetcode, &result1, &resultlen1);
+ if (!rc)
+ rc = pin2hash_if_kdf (app, 1, pinvalue, &result2, &resultlen2);
+ if (!rc)
{
- strcpy (buffer, resetcode);
- rc = pin2hash_if_kdf (app, 0, buffer, &pinlen0);
- if (!rc)
+ bufferlen = resultlen1 + resultlen2;
+ buffer = xtrymalloc (bufferlen);
+ if (!buffer)
+ rc = gpg_error_from_syserror ();
+ else
{
- strcpy (buffer+pinlen0, pinvalue);
- rc = pin2hash_if_kdf (app, 1, buffer+pinlen0, &pinlen);
+ memcpy (buffer, result1, resultlen1);
+ memcpy (buffer+resultlen1, result2, resultlen2);
}
- if (!rc)
- rc = iso7816_reset_retry_counter_with_rc (app_get_slot (app), 0x81,
- buffer, pinlen0+pinlen);
- wipememory (buffer, pinlen0 + pinlen);
- xfree (buffer);
}
+ if (!rc)
+ rc = iso7816_reset_retry_counter_with_rc (app_get_slot (app), 0x81,
+ buffer, bufferlen);
+ wipe_and_free (result1, resultlen1);
+ wipe_and_free (result2, resultlen2);
+ wipe_and_free (buffer, bufferlen);
}
else if (set_resetcode)
{
- if (strlen (pinvalue) < 8)
+ size_t bufferlen = strlen (pinvalue);
+ char *buffer = NULL;
+
+ if (bufferlen && bufferlen < 8)
{
log_error (_("Reset Code is too short; minimum length is %d\n"), 8);
rc = gpg_error (GPG_ERR_BAD_PIN);
}
else
{
- rc = pin2hash_if_kdf (app, 0, pinvalue, &pinlen);
+ rc = pin2hash_if_kdf (app, 0, pinvalue, &buffer, &bufferlen);
if (!rc)
rc = iso7816_put_data (app_get_slot (app),
- 0, 0xD3, pinvalue, pinlen);
+ 0, 0xD3, buffer, bufferlen);
+ wipe_and_free (buffer, bufferlen);
}
}
else if (reset_mode)
{
- rc = pin2hash_if_kdf (app, 1, pinvalue, &pinlen);
+ char *buffer = NULL;
+ size_t bufferlen;
+
+ rc = pin2hash_if_kdf (app, 1, pinvalue, &buffer, &bufferlen);
if (!rc)
rc = iso7816_reset_retry_counter (app_get_slot (app),
- 0x81, pinvalue, pinlen);
+ 0x81, buffer, bufferlen);
if (!rc && !app->app_local->extcap.is_v2)
rc = iso7816_reset_retry_counter (app_get_slot (app),
- 0x82, pinvalue, pinlen);
+ 0x82, buffer, bufferlen);
+ wipe_and_free (buffer, bufferlen);
}
else if (!app->app_local->extcap.is_v2)
{
@@ -3358,35 +3394,29 @@ do_change_pin (app_t app, ctrl_t ctrl, const char *chvnostr,
}
else
{
- rc = pin2hash_if_kdf (app, chvno, oldpinvalue, &pinlen0);
+ char *buffer1 = NULL;
+ char *buffer2 = NULL;
+ size_t bufferlen1, bufferlen2 = 0;
+
+ rc = pin2hash_if_kdf (app, chvno, oldpinvalue, &buffer1, &bufferlen1);
if (!rc)
- rc = pin2hash_if_kdf (app, chvno, pinvalue, &pinlen);
+ rc = pin2hash_if_kdf (app, chvno, pinvalue, &buffer2, &bufferlen2);
if (!rc)
rc = iso7816_change_reference_data (app->slot, 0x80 + chvno,
- oldpinvalue, pinlen0,
- pinvalue, pinlen);
+ buffer1, bufferlen1,
+ buffer2, bufferlen2);
+ wipe_and_free (buffer1, bufferlen1);
+ wipe_and_free (buffer2, bufferlen2);
}
}
- if (pinvalue)
- {
- wipememory (pinvalue, pinlen);
- xfree (pinvalue);
- }
+ wipe_and_free_string (pinvalue);
if (rc)
flush_cache_after_error (app);
leave:
- if (resetcode)
- {
- wipememory (resetcode, strlen (resetcode));
- xfree (resetcode);
- }
- if (oldpinvalue)
- {
- wipememory (oldpinvalue, pinlen0);
- xfree (oldpinvalue);
- }
+ wipe_and_free_string (resetcode);
+ wipe_and_free_string (oldpinvalue);
return rc;
}
@@ -5159,7 +5189,7 @@ do_sign (app_t app, ctrl_t ctrl, const char *keyidstr, int hashalgo,
if (!app->did_chv1 || app->force_chv1)
{
char *pinvalue;
- int pinlen;
+ size_t pinlen;
rc = verify_a_chv (app, ctrl, pincb, pincb_arg, 1, sigcount,
&pinvalue, &pinlen);
@@ -5181,13 +5211,13 @@ do_sign (app_t app, ctrl_t ctrl, const char *keyidstr, int hashalgo,
if (rc)
{
log_error (_("verify CHV%d failed: %s\n"), 2, gpg_strerror (rc));
- xfree (pinvalue);
+ wipe_and_free (pinvalue, pinlen);
flush_cache_after_error (app);
return rc;
}
app->did_chv2 = 1;
}
- xfree (pinvalue);
+ wipe_and_free (pinvalue, pinlen);
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-06-17 20:07:13 +0000