security-and-privacy/gnupg
security-and-privacy/gnupg
1
0
Fork 0
mirror of git://git.gnupg.org/gnupg.git synced 2024-05-31 22:18:03 +02:00
Code Activity

Add user defined pinentry prompts for SCD.

Browse Source 
This adds scdaemon "OPTION pin-prompt" and "OPTION pin-admin-prompt"
along with special escapes to replace in the prompt string to inform the
user of a signature count and admin PIN attempts remaining.

It also adds another "standard" pinentry escape "|I|" to ignore the
default pinentry prompt from gpg-agent and use the supplied 'info'
parameter unmodified (cannot be used with other pinentry flags).

* agent/divert-scd.c (getpin_cb): Add |I| pinentry flag to ignore the
default prompt and use the 'info' parameter as the entire prompt.
* scd/app-common.h (PIN_PROMPT_NONE, PIN_SIGN_PROMPT, PIN_ADMIN_PROMPT):
New enumeration.
(set_pin_prompt): New application callback to set a user-defined
pinentry prompt.
* scd/app-openpgp.c (verify_a_chv): Expand a user-defined pinentry
prompt.
(build_enter_admin_pin_prompt): Ditto.
(do_change_pin): Ditto.
(do_set_pin_prompt): New.
* scd/app.c (expand_pin_prompt): New.
(app_set_pin_prompt): Ditto.
* scd/command.c (set_pinentry_prompt): New.
(option_handler): Add option 'pin-prompt' and 'pin-admin-prompt'.
(open_card): Set the user-defined pinentry prompts after selecting an
application.
This commit is contained in:
Ben Kibbey 2012-01-10 22:10:36 -05:00
parent 30ec869b8c
commit 633ea8531e
6 changed files with 313 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
NEWS
View File

@ -4,6 +4,8 @@ Noteworthy changes in version 2.1.0beta4 (unreleased)
* GPG now accepts a space separated fingerprint as a user ID. This
allows to copy and paste the fingerprint from the key listing.
* New option for SCDAEMON to set a user defined pinentry prompt.
Noteworthy changes in version 2.1.0beta3 (2011-12-20)
-----------------------------------------------------

12
agent/divert-scd.c
View File

@ -166,6 +166,8 @@ encode_md_for_card (const unsigned char *digest, size_t digestlen, int algo,
'A' = The PIN is an Admin PIN, SO-PIN or alike.
'P' = The PIN is a PUK (Personal Unblocking Key).
'R' = The PIN is a Reset Code.
'I' = Ignore using the default prompt and use 'info' as the entire
prompt. Cannot be used with other flags.
Example:
@ -185,6 +187,7 @@ getpin_cb (void *opaque, const char *info, char *buf, size_t maxbuf)
int newpin = 0;
int resetcode = 0;
int is_puk = 0;
int ignore = 0;
const char *again_text = NULL;
const char *prompt = "PIN";
@ -212,6 +215,8 @@ getpin_cb (void *opaque, const char *info, char *buf, size_t maxbuf)
prompt = _("Reset Code");
resetcode = 1;
}
else if (*s == 'I')
ignore = 1;
}
info = ends+1;
any_flags = 1;
@ -219,6 +224,9 @@ getpin_cb (void *opaque, const char *info, char *buf, size_t maxbuf)
else if (info && *info == '|')
log_debug ("pin_cb called without proper PIN info hack\n");
if (ignore)
any_flags = 0;
/* If BUF has been passed as NULL, we are in keypad mode: The
callback opens the popup and immediatley returns. */
if (!buf)
@ -305,8 +313,8 @@ getpin_cb (void *opaque, const char *info, char *buf, size_t maxbuf)
}
else
{
char *desc;
if ( asprintf (&desc,
char *desc = NULL;
if (!ignore && asprintf (&desc,
_("Please enter the PIN%s%s%s to unlock the card"),
info? " (`":"",
info? info:"",

10
scd/app-common.h
View File

@ -34,6 +34,12 @@
#define APP_CHANGE_FLAG_RESET 1
#define APP_CHANGE_FLAG_NULLPIN 2
/* For user defined pinentry prompts. */
enum {
PIN_PROMPT_NONE = -1,
PIN_SIGN_PROMPT,
PIN_ADMIN_PROMPT,
};
struct app_local_s; /* Defined by all app-*.c. */
@ -119,6 +125,7 @@ struct app_ctx_s {
gpg_error_t (*check_pin) (app_t app, const char *keyidstr,
gpg_error_t (*pincb)(void*, const char *, char **),
void *pincb_arg);
gpg_error_t (*set_pin_prompt)(app_t app, int which, const char *prompt);
} fnc;
};
@ -192,6 +199,7 @@ gpg_error_t app_genkey (app_t app, ctrl_t ctrl,
time_t createtime,
gpg_error_t (*pincb)(void*, const char *, char **),
void *pincb_arg);
gpg_error_t app_set_pin_prompt (app_t app, int which, const char *prompt);
gpg_error_t app_get_challenge (app_t app, size_t nbytes,
unsigned char *buffer);
gpg_error_t app_change_pin (app_t app, ctrl_t ctrl,
@ -201,6 +209,8 @@ gpg_error_t app_change_pin (app_t app, ctrl_t ctrl,
gpg_error_t app_check_pin (app_t app, const char *keyidstr,
gpg_error_t (*pincb)(void*, const char *, char **),
void *pincb_arg);
char *expand_pin_prompt(const char *prompt, const char *prepend, int which,
...);
/*-- app-openpgp.c --*/

109
scd/app-openpgp.c
View File

@ -198,6 +198,8 @@ struct app_local_s {
rsa_key_format_t format;
} keyattr[3];
char *pin_prompt; /* As set with set_pin_prompt() or a default. */
char *pin_admin_prompt;
};
@ -242,6 +244,8 @@ do_deinit (app_t app)
xfree (app->app_local->pk[i].key);
app->app_local->pk[i].read_done = 0;
}
xfree (app->app_local->pin_prompt);
xfree (app->app_local->pin_admin_prompt);
xfree (app->app_local);
app->app_local = NULL;
}
@ -1520,19 +1524,41 @@ verify_a_chv (app_t app,
if (chvno == 1)
{
if (app->app_local->pin_prompt)
{
prompt_buffer = expand_pin_prompt (app->app_local->pin_prompt, "|I|",
PIN_SIGN_PROMPT, sigcount);
if (!prompt_buffer)
return gpg_error_from_syserror ();
}
else
{
#define PROMPTSTRING _("||Please enter the PIN%%0A[sigs done: %lu]")
size_t promptsize = strlen (PROMPTSTRING) + 50;
size_t promptsize;
prompt_buffer = xtrymalloc (promptsize);
if (!prompt_buffer)
return gpg_error_from_syserror ();
snprintf (prompt_buffer, promptsize-1, PROMPTSTRING, sigcount);
prompt = prompt_buffer;
promptsize = strlen (PROMPTSTRING) + 50;
prompt_buffer = xtrymalloc (promptsize);
if (!prompt_buffer)
return gpg_error_from_syserror ();
snprintf (prompt_buffer, promptsize-1, PROMPTSTRING, sigcount);
#undef PROMPTSTRING
}
prompt = prompt_buffer;
}
else
prompt = _("||Please enter the PIN");
{
if (app->app_local->pin_prompt)
{
prompt_buffer = expand_pin_prompt (app->app_local->pin_prompt, "|I|",
PIN_PROMPT_NONE, NULL);
if (!prompt_buffer)
return gpg_error_from_syserror ();
prompt = prompt_buffer;
}
else
prompt = _("||Please enter the PIN");
}
if (!opt.disable_keypad
&& !iso7816_check_keypad (app->slot, ISO7816_VERIFY, &pininfo) )
@ -1673,11 +1699,21 @@ build_enter_admin_pin_prompt (app_t app, char **r_prompt)
{
/* TRANSLATORS: Do not translate the "|A|" prefix but keep it at
the start of the string. Use %%0A to force a linefeed. */
prompt = xtryasprintf (_("|A|Please enter the Admin PIN%%0A"
"[remaining attempts: %d]"), remaining);
if (app->app_local->pin_admin_prompt)
prompt = expand_pin_prompt (app->app_local->pin_admin_prompt, "|I|",
PIN_ADMIN_PROMPT, remaining);
else
prompt = xtryasprintf (_("|A|Please enter the Admin PIN%%0A"
"[remaining attempts: %d]"), remaining);
}
else
prompt = xtrystrdup (_("|A|Please enter the Admin PIN"));
{
if (app->app_local->pin_admin_prompt)
prompt = expand_pin_prompt (app->app_local->pin_admin_prompt, "|I|",
PIN_PROMPT_NONE, NULL);
else
prompt = xtrystrdup (_("|A|Please enter the Admin PIN"));
}
if (!prompt)
return gpg_error_from_syserror ();
@ -1999,7 +2035,21 @@ do_change_pin (app_t app, ctrl_t ctrl, const char *chvnostr,
prompt = promptbuf;
}
else
prompt = _("||Please enter the PIN");
{
if (app->app_local->pin_prompt)
{
promptbuf = expand_pin_prompt (app->app_local->pin_prompt,
"|I|", PIN_PROMPT_NONE, NULL);
if (!promptbuf)
{
rc = gpg_error_from_syserror ();
goto leave;
}
prompt = promptbuf;
}
else
prompt = _("||Please enter the PIN");
}
rc = pincb (pincb_arg, prompt, &oldpinvalue);
xfree (promptbuf);
promptbuf = NULL;
@ -3707,6 +3757,40 @@ parse_algorithm_attribute (app_t app, int keyno)
xfree (relptr);
}
gpg_error_t
do_set_pin_prompt(app_t app, int which, const char *prompt)
{
gpg_error_t rc = 0;
char **p = NULL;
switch (which)
{
case PIN_SIGN_PROMPT:
p = &app->app_local->pin_prompt;
break;
case PIN_ADMIN_PROMPT:
p = &app->app_local->pin_admin_prompt;
break;
default:
break;
}
if (p)
{
xfree (*p);
*p = NULL;
if (prompt && *prompt != '-' && *(prompt+1) != 0)
{
*p = xtrystrdup (prompt);
if (!*p)
rc = gpg_error_from_syserror ();
}
}
return rc;
}
/* Select the OpenPGP application on the card in SLOT. This function
must be used before any other OpenPGP application functions. */
gpg_error_t
@ -3850,6 +3934,7 @@ app_select_openpgp (app_t app)
app->fnc.decipher = do_decipher;
app->fnc.change_pin = do_change_pin;
app->fnc.check_pin = do_check_pin;
app->fnc.set_pin_prompt = do_set_pin_prompt;
}
leave:

125
scd/app.c
View File

@ -922,6 +922,131 @@ app_genkey (app_t app, ctrl_t ctrl, const char *keynostr, unsigned int flags,
return err;
}
/* For use with user-defined pinentry prompts that are set with the OPTION
* command. This function is called from an application before a pinentry is
* invoked. It replaces special escape strings in the user-defined 'prompt'
* with a single (for now) value set by the calling function. What data type
* the vararg value is depends on the 'which' parameter and is set in the
* calling function.
*
* The 'prepend' parameter are any pinentry flags to be prepended to the
* expanded prompt. These flags, if any, are not set by the user-defined
* prompt but the calling function. In most cases it will be NULL or "|I|".
*
* The following expandos are recognized:
*
* expando | which | description
* ----------------------------------------
* PIN_PROMPT_NONE NOP. The user-defined prompt is returned along
* with any 'prepend' parameter.
* |S| PIN_SIGN_PROMPT signature count (unsigned long)
* |A| PIN_ADMIN_PROMPT remaining attempts (int)
*
* The following example shows the default pinentry prompt when no
* user-defined prompt is set:
*
* "Please enter the PIN%%0A[sigs done: |S|]"
*
* Here, |S| is expanded to the number of signatures created so far.
*/
char *
expand_pin_prompt(const char *prompt, const char *prepend, int which, ...)
{
va_list ap;
size_t len, n;
char *buf;
unsigned long luval;
int intval;
char valuebuf[50] = {0};
char *p, *token = NULL, *tokenp;
if (!prompt)
return NULL;
len = strlen (prompt);
len += prepend ? strlen (prepend) : 0;
va_start (ap, which);
switch (which)
{
/* Signature count. */
case PIN_SIGN_PROMPT:
luval = va_arg (ap, unsigned long);
snprintf (valuebuf, sizeof (valuebuf), "%lu", luval);
token = "|S|";
break;
/* Pin tries remaining. */
case PIN_ADMIN_PROMPT:
intval = va_arg (ap, int);
snprintf (valuebuf, sizeof (valuebuf), "%i", intval);
token = "|A|";
break;
default:
break;
}
va_end (ap);
if (!token)
{
if (prepend)
{
len = strlen (prepend)+strlen (prompt)+1;
p = xtrymalloc (len);
if (!p)
return NULL;
snprintf (p, len, "%s%s", prepend, prompt);
return p;
}
return xtrystrdup (prompt);
}
len += strlen (valuebuf)+1;
buf = xtrymalloc (len);
if (!buf)
return NULL;
buf[0] = 0;
if (prepend)
strcpy (buf, prepend);
strcat (buf, prompt);
if (prepend)
p = buf+strlen (prepend);
else
p = buf;
tokenp = strstr (p, token);
if (!tokenp)
return buf;
p = tokenp+strlen (token);
len -= strlen (token)+1;
memmove(&buf[len-strlen (p)], p, strlen (p));
for (n = 0; valuebuf[n]; n++)
*tokenp++ = valuebuf[n];
buf[len] = 0;
return buf;
}
/* Set the prompt shown in the pinentry dialog. If not set then a default will
* be used. */
gpg_error_t
app_set_pin_prompt(app_t app, int which, const char *prompt)
{
if (!app)
return gpg_error (GPG_ERR_INV_VALUE);
if (!app->fnc.set_pin_prompt)
return gpg_error (GPG_ERR_UNSUPPORTED_OPERATION);
return app->fnc.set_pin_prompt (app, which, prompt);
}
/* Perform a GET CHALLENGE operation. This fucntion is special as it
directly accesses the card without any application specific

70
scd/command.c
View File

@ -139,6 +139,13 @@ struct server_local_s
this session. */
int stopme;
/* User-defined pinentry prompt strings. Needed both here and in the app
* since they may be set by the user before an app is selected with
* select_application(). They are copied to the app when
* select_application() succeeds and further modifications done in the app.
* */
char *pin_prompt;
char *pin_admin_prompt;
};
@ -387,6 +394,39 @@ reset_notify (assuan_context_t ctx, char *line)
return 0;
}
static gpg_error_t
set_pinentry_prompt(struct server_local_s *srv, int which, const char *prompt)
{
gpg_error_t rc = 0;
char **p = NULL;
switch (which)
{
case PIN_SIGN_PROMPT:
p = &srv->pin_prompt;
break;
case PIN_ADMIN_PROMPT:
p = &srv->pin_admin_prompt;
break;
default:
break;
}
if (p)
{
xfree (*p);
*p = NULL;
if (prompt && *prompt != '-' && *(prompt+1) != 0)
{
*p = xtrystrdup (prompt);
if (!*p)
rc = gpg_error_from_syserror ();
}
}
return rc;
}
static gpg_error_t
option_handler (assuan_context_t ctx, const char *key, const char *value)
@ -407,6 +447,22 @@ option_handler (assuan_context_t ctx, const char *key, const char *value)
ctrl->server_local->event_signal = i;
#endif
}
/* A user-defined prompt to show in a pinentry overriding the default. See
* app.c:expand_pin_prompt() for details. */
else if (!strcmp (key, "pin-prompt"))
{
if (ctrl->app_ctx)
return app_set_pin_prompt (ctrl->app_ctx, PIN_SIGN_PROMPT, value);
else
return set_pinentry_prompt (ctrl->server_local, PIN_SIGN_PROMPT, value);
}
else if (!strcmp (key, "pin-admin-prompt"))
{
if (ctrl->app_ctx)
return app_set_pin_prompt (ctrl->app_ctx, PIN_ADMIN_PROMPT, value);
else
return set_pinentry_prompt (ctrl->server_local, PIN_ADMIN_PROMPT, value);
}
return 0;
}
@ -523,7 +579,17 @@ open_card (ctrl_t ctrl, const char *apptype)
err = gpg_error (GPG_ERR_CARD);
}
else
err = select_application (ctrl, slot, apptype, &ctrl->app_ctx);
{
err = select_application (ctrl, slot, apptype, &ctrl->app_ctx);
if (!err)
{
err = app_set_pin_prompt(ctrl->app_ctx, PIN_SIGN_PROMPT,
ctrl->server_local->pin_prompt);
if (!err)
err = app_set_pin_prompt(ctrl->app_ctx, PIN_ADMIN_PROMPT,
ctrl->server_local->pin_admin_prompt);
}
}
}
TEST_CARD_REMOVAL (ctrl, err);
@ -2097,6 +2163,8 @@ scd_command_handler (ctrl_t ctrl, int fd)
sl->next_session = ctrl->server_local->next_session;
}
stopme = ctrl->server_local->stopme || reader_disabled;
xfree (ctrl->server_local->pin_prompt);
xfree (ctrl->server_local->pin_admin_prompt);
xfree (ctrl->server_local);
ctrl->server_local = NULL;