summaryrefslogtreecommitdiffstats
path: root/agent/genkey.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--agent/genkey.c619
1 files changed, 619 insertions, 0 deletions
diff --git a/agent/genkey.c b/agent/genkey.c
new file mode 100644
index 0000000..5c6ae93
--- /dev/null
+++ b/agent/genkey.c
@@ -0,0 +1,619 @@
+/* genkey.c - Generate a keypair
+ * Copyright (C) 2002, 2003, 2004, 2007, 2010 Free Software Foundation, Inc.
+ * Copyright (C) 2015 g10 Code GmbH.
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <assert.h>
+
+#include "agent.h"
+#include "../common/i18n.h"
+#include "../common/exechelp.h"
+#include "../common/sysutils.h"
+
+static int
+store_key (gcry_sexp_t private, const char *passphrase, int force,
+ unsigned long s2k_count, time_t timestamp)
+{
+ int rc;
+ unsigned char *buf;
+ size_t len;
+ unsigned char grip[20];
+
+ if ( !gcry_pk_get_keygrip (private, grip) )
+ {
+ log_error ("can't calculate keygrip\n");
+ return gpg_error (GPG_ERR_GENERAL);
+ }
+
+ len = gcry_sexp_sprint (private, GCRYSEXP_FMT_CANON, NULL, 0);
+ assert (len);
+ buf = gcry_malloc_secure (len);
+ if (!buf)
+ return out_of_core ();
+ len = gcry_sexp_sprint (private, GCRYSEXP_FMT_CANON, buf, len);
+ assert (len);
+
+ if (passphrase)
+ {
+ unsigned char *p;
+
+ rc = agent_protect (buf, passphrase, &p, &len, s2k_count, -1);
+ if (rc)
+ {
+ xfree (buf);
+ return rc;
+ }
+ xfree (buf);
+ buf = p;
+ }
+
+ rc = agent_write_private_key (grip, buf, len, force, timestamp);
+ xfree (buf);
+ return rc;
+}
+
+
+/* Count the number of non-alpha characters in S. Control characters
+ and non-ascii characters are not considered. */
+static size_t
+nonalpha_count (const char *s)
+{
+ size_t n;
+
+ for (n=0; *s; s++)
+ if (isascii (*s) && ( isdigit (*s) || ispunct (*s) ))
+ n++;
+
+ return n;
+}
+
+
+/* Check PW against a list of pattern. Return 0 if PW does not match
+ these pattern. */
+static int
+check_passphrase_pattern (ctrl_t ctrl, const char *pw)
+{
+ gpg_error_t err = 0;
+ const char *pgmname = gnupg_module_name (GNUPG_MODULE_NAME_CHECK_PATTERN);
+ FILE *infp;
+ const char *argv[10];
+ pid_t pid;
+ int result, i;
+
+ (void)ctrl;
+
+ infp = gnupg_tmpfile ();
+ if (!infp)
+ {
+ err = gpg_error_from_syserror ();
+ log_error (_("error creating temporary file: %s\n"), gpg_strerror (err));
+ return 1; /* Error - assume password should not be used. */
+ }
+
+ if (fwrite (pw, strlen (pw), 1, infp) != 1)
+ {
+ err = gpg_error_from_syserror ();
+ log_error (_("error writing to temporary file: %s\n"),
+ gpg_strerror (err));
+ fclose (infp);
+ return 1; /* Error - assume password should not be used. */
+ }
+ fseek (infp, 0, SEEK_SET);
+ clearerr (infp);
+
+ i = 0;
+ argv[i++] = "--null";
+ argv[i++] = "--",
+ argv[i++] = opt.check_passphrase_pattern,
+ argv[i] = NULL;
+ assert (i < sizeof argv);
+
+ if (gnupg_spawn_process_fd (pgmname, argv, fileno (infp), -1, -1, &pid))
+ result = 1; /* Execute error - assume password should no be used. */
+ else if (gnupg_wait_process (pgmname, pid, 1, NULL))
+ result = 1; /* Helper returned an error - probably a match. */
+ else
+ result = 0; /* Success; i.e. no match. */
+ gnupg_release_process (pid);
+
+ /* Overwrite our temporary file. */
+ fseek (infp, 0, SEEK_SET);
+ clearerr (infp);
+ for (i=((strlen (pw)+99)/100)*100; i > 0; i--)
+ putc ('\xff', infp);
+ fflush (infp);
+ fclose (infp);
+ return result;
+}
+
+
+static int
+take_this_one_anyway2 (ctrl_t ctrl, const char *desc, const char *anyway_btn)
+{
+ gpg_error_t err;
+
+ if (opt.enforce_passphrase_constraints)
+ {
+ err = agent_show_message (ctrl, desc, L_("Enter new passphrase"));
+ if (!err)
+ err = gpg_error (GPG_ERR_CANCELED);
+ }
+ else
+ err = agent_get_confirmation (ctrl, desc,
+ anyway_btn, L_("Enter new passphrase"), 0);
+ return err;
+}
+
+
+static int
+take_this_one_anyway (ctrl_t ctrl, const char *desc)
+{
+ return take_this_one_anyway2 (ctrl, desc, L_("Take this one anyway"));
+}
+
+
+/* Check whether the passphrase PW is suitable. Returns 0 if the
+ passphrase is suitable and true if it is not and the user should be
+ asked to provide a different one. If FAILED_CONSTRAINT is set, a
+ message describing the problem is returned in
+ *FAILED_CONSTRAINT. */
+int
+check_passphrase_constraints (ctrl_t ctrl, const char *pw, int no_empty,
+ char **failed_constraint)
+{
+ gpg_error_t err = 0;
+ unsigned int minlen = opt.min_passphrase_len;
+ unsigned int minnonalpha = opt.min_passphrase_nonalpha;
+ char *msg1 = NULL;
+ char *msg2 = NULL;
+ char *msg3 = NULL;
+
+ if (ctrl && ctrl->pinentry_mode == PINENTRY_MODE_LOOPBACK)
+ return 0;
+
+ if (!pw)
+ pw = "";
+
+ /* The first check is to warn about an empty passphrase. */
+ if (!*pw)
+ {
+ const char *desc = (opt.enforce_passphrase_constraints || no_empty?
+ L_("You have not entered a passphrase!%0A"
+ "An empty passphrase is not allowed.") :
+ L_("You have not entered a passphrase - "
+ "this is in general a bad idea!%0A"
+ "Please confirm that you do not want to "
+ "have any protection on your key."));
+
+ err = 1;
+ if (failed_constraint)
+ {
+ if (opt.enforce_passphrase_constraints || no_empty)
+ *failed_constraint = xstrdup (desc);
+ else
+ err = take_this_one_anyway2 (ctrl, desc,
+ L_("Yes, protection is not needed"));
+ }
+
+ goto leave;
+ }
+
+ /* Now check the constraints and collect the error messages unless
+ in silent mode which returns immediately. */
+ if (utf8_charcount (pw, -1) < minlen )
+ {
+ if (!failed_constraint)
+ {
+ err = gpg_error (GPG_ERR_INV_PASSPHRASE);
+ goto leave;
+ }
+
+ msg1 = xtryasprintf
+ ( ngettext ("A passphrase should be at least %u character long.",
+ "A passphrase should be at least %u characters long.",
+ minlen), minlen );
+ if (!msg1)
+ {
+ err = gpg_error_from_syserror ();
+ goto leave;
+ }
+ }
+
+ if (nonalpha_count (pw) < minnonalpha )
+ {
+ if (!failed_constraint)
+ {
+ err = gpg_error (GPG_ERR_INV_PASSPHRASE);
+ goto leave;
+ }
+
+ msg2 = xtryasprintf
+ ( ngettext ("A passphrase should contain at least %u digit or%%0A"
+ "special character.",
+ "A passphrase should contain at least %u digits or%%0A"
+ "special characters.",
+ minnonalpha), minnonalpha );
+ if (!msg2)
+ {
+ err = gpg_error_from_syserror ();
+ goto leave;
+ }
+ }
+
+ /* If configured check the passphrase against a list of known words
+ and pattern. The actual test is done by an external program.
+ The warning message is generic to give the user no hint on how to
+ circumvent this list. */
+ if (*pw && opt.check_passphrase_pattern &&
+ check_passphrase_pattern (ctrl, pw))
+ {
+ if (!failed_constraint)
+ {
+ err = gpg_error (GPG_ERR_INV_PASSPHRASE);
+ goto leave;
+ }
+
+ msg3 = xtryasprintf
+ (L_("A passphrase may not be a known term or match%%0A"
+ "certain pattern."));
+ if (!msg3)
+ {
+ err = gpg_error_from_syserror ();
+ goto leave;
+ }
+ }
+
+ if (failed_constraint && (msg1 || msg2 || msg3))
+ {
+ char *msg;
+ size_t n;
+
+ msg = strconcat
+ (L_("Warning: You have entered an insecure passphrase."),
+ "%0A%0A",
+ msg1? msg1 : "", msg1? "%0A" : "",
+ msg2? msg2 : "", msg2? "%0A" : "",
+ msg3? msg3 : "", msg3? "%0A" : "",
+ NULL);
+ if (!msg)
+ {
+ err = gpg_error_from_syserror ();
+ goto leave;
+ }
+ /* Strip a trailing "%0A". */
+ n = strlen (msg);
+ if (n > 3 && !strcmp (msg + n - 3, "%0A"))
+ msg[n-3] = 0;
+
+ err = 1;
+ if (opt.enforce_passphrase_constraints)
+ *failed_constraint = msg;
+ else
+ {
+ err = take_this_one_anyway (ctrl, msg);
+ xfree (msg);
+ }
+ }
+
+ leave:
+ xfree (msg1);
+ xfree (msg2);
+ xfree (msg3);
+ return err;
+}
+
+
+/* Callback function to compare the first entered PIN with the one
+ currently being entered. */
+static gpg_error_t
+reenter_compare_cb (struct pin_entry_info_s *pi)
+{
+ const char *pin1 = pi->check_cb_arg;
+
+ if (!strcmp (pin1, pi->pin))
+ return 0; /* okay */
+ return gpg_error (GPG_ERR_BAD_PASSPHRASE);
+}
+
+
+/* Ask the user for a new passphrase using PROMPT. On success the
+ function returns 0 and store the passphrase at R_PASSPHRASE; if the
+ user opted not to use a passphrase NULL will be stored there. The
+ user needs to free the returned string. In case of an error and
+ error code is returned and NULL stored at R_PASSPHRASE. */
+gpg_error_t
+agent_ask_new_passphrase (ctrl_t ctrl, const char *prompt,
+ char **r_passphrase)
+{
+ gpg_error_t err;
+ const char *text1 = prompt;
+ const char *text2 = L_("Please re-enter this passphrase");
+ char *initial_errtext = NULL;
+ struct pin_entry_info_s *pi, *pi2;
+
+ *r_passphrase = NULL;
+
+ if (ctrl->pinentry_mode == PINENTRY_MODE_LOOPBACK)
+ {
+ size_t size;
+ unsigned char *buffer;
+
+ err = pinentry_loopback (ctrl, "NEW_PASSPHRASE", &buffer, &size,
+ MAX_PASSPHRASE_LEN);
+ if (!err)
+ {
+ if (size)
+ {
+ buffer[size] = 0;
+ *r_passphrase = buffer;
+ }
+ else
+ *r_passphrase = NULL;
+ }
+ return err;
+ }
+
+ pi = gcry_calloc_secure (1, sizeof (*pi) + MAX_PASSPHRASE_LEN + 1);
+ if (!pi)
+ return gpg_error_from_syserror ();
+ pi2 = gcry_calloc_secure (1, sizeof (*pi2) + MAX_PASSPHRASE_LEN + 1);
+ if (!pi2)
+ {
+ err = gpg_error_from_syserror ();
+ xfree (pi2);
+ return err;
+ }
+ pi->max_length = MAX_PASSPHRASE_LEN + 1;
+ pi->max_tries = 3;
+ pi->with_qualitybar = 0;
+ pi->with_repeat = 1;
+ pi2->max_length = MAX_PASSPHRASE_LEN + 1;
+ pi2->max_tries = 3;
+ pi2->check_cb = reenter_compare_cb;
+ pi2->check_cb_arg = pi->pin;
+
+ next_try:
+ err = agent_askpin (ctrl, text1, NULL, initial_errtext, pi, NULL, 0);
+ xfree (initial_errtext);
+ initial_errtext = NULL;
+ if (!err)
+ {
+ if (check_passphrase_constraints (ctrl, pi->pin, 0, &initial_errtext))
+ {
+ pi->failed_tries = 0;
+ pi2->failed_tries = 0;
+ goto next_try;
+ }
+ /* Unless the passphrase is empty or the pinentry told us that
+ it already did the repetition check, ask to confirm it. */
+ if (*pi->pin && !pi->repeat_okay)
+ {
+ err = agent_askpin (ctrl, text2, NULL, NULL, pi2, NULL, 0);
+ if (gpg_err_code (err) == GPG_ERR_BAD_PASSPHRASE)
+ { /* The re-entered one did not match and the user did not
+ hit cancel. */
+ initial_errtext = xtrystrdup (L_("does not match - try again"));
+ if (initial_errtext)
+ goto next_try;
+ err = gpg_error_from_syserror ();
+ }
+ }
+ }
+
+ if (!err && *pi->pin)
+ {
+ /* User wants a passphrase. */
+ *r_passphrase = xtrystrdup (pi->pin);
+ if (!*r_passphrase)
+ err = gpg_error_from_syserror ();
+ }
+
+ xfree (initial_errtext);
+ xfree (pi2);
+ xfree (pi);
+ return err;
+}
+
+
+
+/* Generate a new keypair according to the parameters given in
+ KEYPARAM. If CACHE_NONCE is given first try to lookup a passphrase
+ using the cache nonce. If NO_PROTECTION is true the key will not
+ be protected by a passphrase. If OVERRIDE_PASSPHRASE is true that
+ passphrase will be used for the new key. If TIMESTAMP is not zero
+ it will be recorded as creation date of the key (unless extended
+ format is disabled) . */
+int
+agent_genkey (ctrl_t ctrl, const char *cache_nonce, time_t timestamp,
+ const char *keyparam, size_t keyparamlen, int no_protection,
+ const char *override_passphrase, int preset, membuf_t *outbuf)
+{
+ gcry_sexp_t s_keyparam, s_key, s_private, s_public;
+ char *passphrase_buffer = NULL;
+ const char *passphrase;
+ int rc;
+ size_t len;
+ char *buf;
+
+ rc = gcry_sexp_sscan (&s_keyparam, NULL, keyparam, keyparamlen);
+ if (rc)
+ {
+ log_error ("failed to convert keyparam: %s\n", gpg_strerror (rc));
+ return gpg_error (GPG_ERR_INV_DATA);
+ }
+
+ /* Get the passphrase now, cause key generation may take a while. */
+ if (override_passphrase)
+ passphrase = override_passphrase;
+ else if (no_protection || !cache_nonce)
+ passphrase = NULL;
+ else
+ {
+ passphrase_buffer = agent_get_cache (ctrl, cache_nonce, CACHE_MODE_NONCE);
+ passphrase = passphrase_buffer;
+ }
+
+ if (passphrase || no_protection)
+ ;
+ else
+ {
+ rc = agent_ask_new_passphrase (ctrl,
+ L_("Please enter the passphrase to%0A"
+ "protect your new key"),
+ &passphrase_buffer);
+ if (rc)
+ return rc;
+ passphrase = passphrase_buffer;
+ }
+
+ rc = gcry_pk_genkey (&s_key, s_keyparam );
+ gcry_sexp_release (s_keyparam);
+ if (rc)
+ {
+ log_error ("key generation failed: %s\n", gpg_strerror (rc));
+ xfree (passphrase_buffer);
+ return rc;
+ }
+
+ /* break out the parts */
+ s_private = gcry_sexp_find_token (s_key, "private-key", 0);
+ if (!s_private)
+ {
+ log_error ("key generation failed: invalid return value\n");
+ gcry_sexp_release (s_key);
+ xfree (passphrase_buffer);
+ return gpg_error (GPG_ERR_INV_DATA);
+ }
+ s_public = gcry_sexp_find_token (s_key, "public-key", 0);
+ if (!s_public)
+ {
+ log_error ("key generation failed: invalid return value\n");
+ gcry_sexp_release (s_private);
+ gcry_sexp_release (s_key);
+ xfree (passphrase_buffer);
+ return gpg_error (GPG_ERR_INV_DATA);
+ }
+ gcry_sexp_release (s_key); s_key = NULL;
+
+ /* store the secret key */
+ if (DBG_CRYPTO)
+ log_debug ("storing private key\n");
+ rc = store_key (s_private, passphrase, 0, ctrl->s2k_count, timestamp);
+ if (!rc)
+ {
+ if (!cache_nonce)
+ {
+ char tmpbuf[12];
+ gcry_create_nonce (tmpbuf, 12);
+ cache_nonce = bin2hex (tmpbuf, 12, NULL);
+ }
+ if (cache_nonce
+ && !no_protection
+ && !agent_put_cache (ctrl, cache_nonce, CACHE_MODE_NONCE,
+ passphrase, ctrl->cache_ttl_opt_preset))
+ agent_write_status (ctrl, "CACHE_NONCE", cache_nonce, NULL);
+ if (preset && !no_protection)
+ {
+ unsigned char grip[20];
+ char hexgrip[40+1];
+ if (gcry_pk_get_keygrip (s_private, grip))
+ {
+ bin2hex(grip, 20, hexgrip);
+ rc = agent_put_cache (ctrl, hexgrip, CACHE_MODE_ANY, passphrase,
+ ctrl->cache_ttl_opt_preset);
+ }
+ }
+ }
+ xfree (passphrase_buffer);
+ passphrase_buffer = NULL;
+ passphrase = NULL;
+ gcry_sexp_release (s_private);
+ if (rc)
+ {
+ gcry_sexp_release (s_public);
+ return rc;
+ }
+
+ /* return the public key */
+ if (DBG_CRYPTO)
+ log_debug ("returning public key\n");
+ len = gcry_sexp_sprint (s_public, GCRYSEXP_FMT_CANON, NULL, 0);
+ assert (len);
+ buf = xtrymalloc (len);
+ if (!buf)
+ {
+ gpg_error_t tmperr = out_of_core ();
+ gcry_sexp_release (s_private);
+ gcry_sexp_release (s_public);
+ return tmperr;
+ }
+ len = gcry_sexp_sprint (s_public, GCRYSEXP_FMT_CANON, buf, len);
+ assert (len);
+ put_membuf (outbuf, buf, len);
+ gcry_sexp_release (s_public);
+ xfree (buf);
+
+ return 0;
+}
+
+
+
+/* Apply a new passphrase to the key S_SKEY and store it. If
+ PASSPHRASE_ADDR and *PASSPHRASE_ADDR are not NULL, use that
+ passphrase. If PASSPHRASE_ADDR is not NULL store a newly entered
+ passphrase at that address. */
+gpg_error_t
+agent_protect_and_store (ctrl_t ctrl, gcry_sexp_t s_skey,
+ char **passphrase_addr)
+{
+ gpg_error_t err;
+
+ if (passphrase_addr && *passphrase_addr)
+ {
+ /* Take an empty string as request not to protect the key. */
+ err = store_key (s_skey, **passphrase_addr? *passphrase_addr:NULL, 1,
+ ctrl->s2k_count, 0);
+ }
+ else
+ {
+ char *pass = NULL;
+
+ if (passphrase_addr)
+ {
+ xfree (*passphrase_addr);
+ *passphrase_addr = NULL;
+ }
+ err = agent_ask_new_passphrase (ctrl,
+ L_("Please enter the new passphrase"),
+ &pass);
+ if (!err)
+ err = store_key (s_skey, pass, 1, ctrl->s2k_count, 0);
+ if (!err && passphrase_addr)
+ *passphrase_addr = pass;
+ else
+ xfree (pass);
+ }
+
+ return err;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-16 22:25:58 +0000