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findkey.c
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findkey.c
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/* findkey.c - Locate the secret key
* Copyright (C) 2001, 2002, 2003, 2004, 2005, 2007,
* 2010, 2011 Free Software Foundation, Inc.
* Copyright (C) 2014, 2019 Werner Koch
* Copyright (C) 2023 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 <fcntl.h>
#include <unistd.h>
#include <sys/stat.h>
#include <npth.h> /* (we use pth_sleep) */
#include "agent.h"
#include "../common/i18n.h"
#include "../common/ssh-utils.h"
#ifndef O_BINARY
#define O_BINARY 0
#endif
static gpg_error_t read_key_file (const unsigned char *grip,
gcry_sexp_t *result, nvc_t *r_keymeta,
char **r_orig_key_value);
static gpg_error_t is_shadowed_key (gcry_sexp_t s_skey);
/* Helper to pass data to the check callback of the unprotect function. */
struct try_unprotect_arg_s
{
ctrl_t ctrl;
const unsigned char *protected_key;
unsigned char *unprotected_key;
int change_required; /* Set by the callback to indicate that the
user should change the passphrase. */
};
/* Return the file name for the 20 byte keygrip GRIP. With FOR_NEW
* create a file name for later renaming to the actual name. Return
* NULL on error. */
static char *
fname_from_keygrip (const unsigned char *grip, int for_new)
{
char hexgrip[40+4+4+1];
bin2hex (grip, 20, hexgrip);
strcpy (hexgrip+40, for_new? ".key.tmp" : ".key");
return make_filename_try (gnupg_homedir (), GNUPG_PRIVATE_KEYS_DIR,
hexgrip, NULL);
}
/* Replace all linefeeds in STRING by "%0A" and return a new malloced
* string. May return NULL on memory error. */
static char *
linefeed_to_percent0A (const char *string)
{
const char *s;
size_t n;
char *buf, *p;
for (n=0, s=string; *s; s++)
if (*s == '\n')
n += 3;
else
n++;
p = buf = xtrymalloc (n+1);
if (!buf)
return NULL;
for (s=string; *s; s++)
if (*s == '\n')
{
memcpy (p, "%0A", 3);
p += 3;
}
else
*p++ = *s;
*p = 0;
return buf;
}
/* Write the S-expression formatted key (BUFFER,LENGTH) to our key
* storage. With FORCE passed as true an existing key with the given
* GRIP will get overwritten. If SERIALNO and KEYREF are given a
* Token line is added to the key if the extended format is used. If
* TIMESTAMP is not zero and the key does not yet exists it will be
* recorded as creation date. */
gpg_error_t
agent_write_private_key (const unsigned char *grip,
const void *buffer, size_t length, int force,
const char *serialno, const char *keyref,
const char *dispserialno,
time_t timestamp)
{
gpg_error_t err;
char *fname = NULL;
char *tmpfname = NULL;
estream_t fp = NULL;
int newkey;
nvc_t pk = NULL;
gcry_sexp_t key = NULL;
int removetmp = 0;
char *token0 = NULL;
char *token = NULL;
char *dispserialno_buffer = NULL;
char **tokenfields = NULL;
int is_regular;
int blocksigs = 0;
char *orig_key_value = NULL;
const char *s;
int force_modify = 0;
fname = fname_from_keygrip (grip, 0);
if (!fname)
return gpg_error_from_syserror ();
err = read_key_file (grip, &key, &pk, &orig_key_value);
if (err)
{
if (gpg_err_code (err) == GPG_ERR_ENOENT)
newkey = 1;
else
{
log_error ("can't open '%s': %s\n", fname, gpg_strerror (err));
goto leave;
}
}
nvc_modified (pk, 1); /* Clear that flag after a read. */
if (!pk)
{
/* Key is still in the old format or does not exist - create a
* new container. */
pk = nvc_new_private_key ();
if (!pk)
{
err = gpg_error_from_syserror ();
goto leave;
}
force_modify = 1;
}
/* Check whether we already have a regular key. */
is_regular = (key && gpg_err_code (is_shadowed_key (key)) != GPG_ERR_TRUE);
/* Turn (BUFFER,LENGTH) into a gcrypt s-expression and set it into
* our name value container. */
gcry_sexp_release (key);
err = gcry_sexp_sscan (&key, NULL, buffer, length);
if (err)
goto leave;
err = nvc_set_private_key (pk, key);
if (err)
goto leave;
/* Detect whether the key value actually changed and if not clear
* the modified flag. This extra check is required because
* read_key_file removes the Key entry from the container and we
* then create a new Key entry which might be the same, though. */
if (!force_modify
&& orig_key_value && (s = nvc_get_string (pk, "Key:"))
&& !strcmp (orig_key_value, s))
{
nvc_modified (pk, 1); /* Clear that flag. */
}
xfree (orig_key_value);
orig_key_value = NULL;
/* Check that we do not update a regular key with a shadow key. */
if (is_regular && gpg_err_code (is_shadowed_key (key)) == GPG_ERR_TRUE)
{
log_info ("updating regular key file '%s'"
" by a shadow key inhibited\n", fname);
err = 0; /* Simply ignore the error. */
goto leave;
}
/* Check that we update a regular key only in force mode. */
if (is_regular && !force)
{
log_error ("secret key file '%s' already exists\n", fname);
err = gpg_error (GPG_ERR_EEXIST);
goto leave;
}
/* If requested write a Token line. */
if (serialno && keyref)
{
nve_t item;
size_t token0len;
if (dispserialno)
{
/* Escape the DISPSERIALNO. */
dispserialno_buffer = percent_plus_escape (dispserialno);
if (!dispserialno_buffer)
{
err = gpg_error_from_syserror ();
goto leave;
}
dispserialno = dispserialno_buffer;
}
token0 = strconcat (serialno, " ", keyref, NULL);
if (token0)
token = strconcat (token0, " - ", dispserialno? dispserialno:"-", NULL);
if (!token0 || !token)
{
err = gpg_error_from_syserror ();
goto leave;
}
token0len = strlen (token0);
for (item = nvc_lookup (pk, "Token:");
item;
item = nve_next_value (item, "Token:"))
if ((s = nve_value (item)) && !strncmp (s, token0, token0len))
break;
if (!item)
{
/* No token or no token with that value exists. Add a new
* one so that keys which have been stored on several cards
* are well supported. */
err = nvc_add (pk, "Token:", token);
if (err)
goto leave;
}
else
{
/* Token exists: Update the display s/n. It may have
* changed due to changes in a newer software version. */
if (s && (tokenfields = strtokenize (s, " \t\n"))
&& tokenfields[0] && tokenfields[1] && tokenfields[2]
&& tokenfields[3]
&& !strcmp (tokenfields[3], dispserialno))
; /* No need to update Token entry. */
else
{
err = nve_set (pk, item, token);
if (err)
goto leave;
}
}
}
/* If a timestamp has been supplied and the key is new, write a
* creation timestamp. (We douple check that there is no Created
* item yet.)*/
if (timestamp && newkey && !nvc_lookup (pk, "Created:"))
{
gnupg_isotime_t timebuf;
epoch2isotime (timebuf, timestamp);
err = nvc_add (pk, "Created:", timebuf);
if (err)
goto leave;
}
/* Check whether we need to write the file at all. */
if (!nvc_modified (pk, 0))
{
err = 0;
goto leave;
}
/* Create a temporary file for writing. */
tmpfname = fname_from_keygrip (grip, 1);
fp = tmpfname ? es_fopen (tmpfname, "wbx,mode=-rw") : NULL;
if (!fp)
{
err = gpg_error_from_syserror ();
log_error ("can't create '%s': %s\n", tmpfname, gpg_strerror (err));
goto leave;
}
err = nvc_write (pk, fp);
if (!err && es_fflush (fp))
err = gpg_error_from_syserror ();
if (err)
{
log_error ("error writing '%s': %s\n", tmpfname, gpg_strerror (err));
removetmp = 1;
goto leave;
}
if (es_fclose (fp))
{
err = gpg_error_from_syserror ();
log_error ("error closing '%s': %s\n", tmpfname, gpg_strerror (err));
removetmp = 1;
goto leave;
}
else
fp = NULL;
err = gnupg_rename_file (tmpfname, fname, &blocksigs);
if (err)
{
err = gpg_error_from_syserror ();
log_error ("error renaming '%s': %s\n", tmpfname, gpg_strerror (err));
removetmp = 1;
goto leave;
}
bump_key_eventcounter ();
leave:
if (blocksigs)
gnupg_unblock_all_signals ();
es_fclose (fp);
if (removetmp && tmpfname)
gnupg_remove (tmpfname);
xfree (orig_key_value);
xfree (fname);
xfree (tmpfname);
xfree (token);
xfree (token0);
xfree (dispserialno_buffer);
xfree (tokenfields);
gcry_sexp_release (key);
nvc_release (pk);
return err;
}
gpg_error_t
agent_update_private_key (const unsigned char *grip, nvc_t pk)
{
gpg_error_t err;
char *fname0 = NULL; /* The existing file name. */
char *fname = NULL; /* The temporary new file name. */
estream_t fp = NULL;
int removetmp = 0;
int blocksigs = 0;
fname0 = fname_from_keygrip (grip, 0);
if (!fname0)
{
err = gpg_error_from_syserror ();
goto leave;
}
fname = fname_from_keygrip (grip, 1);
if (!fname)
{
err = gpg_error_from_syserror ();
goto leave;
}
fp = es_fopen (fname, "wbx,mode=-rw");
if (!fp)
{
err = gpg_error_from_syserror ();
log_error ("can't create '%s': %s\n", fname, gpg_strerror (err));
goto leave;
}
err = nvc_write (pk, fp);
if (err)
{
log_error ("error writing '%s': %s\n", fname, gpg_strerror (err));
removetmp = 1;
goto leave;
}
es_fclose (fp);
fp = NULL;
err = gnupg_rename_file (fname, fname0, &blocksigs);
if (err)
{
err = gpg_error_from_syserror ();
log_error ("error renaming '%s': %s\n", fname, gpg_strerror (err));
removetmp = 1;
goto leave;
}
leave:
if (blocksigs)
gnupg_unblock_all_signals ();
es_fclose (fp);
if (removetmp && fname)
gnupg_remove (fname);
xfree (fname);
xfree (fname0);
return err;
}
/* Callback function to try the unprotection from the passphrase query
code. */
static gpg_error_t
try_unprotect_cb (struct pin_entry_info_s *pi)
{
struct try_unprotect_arg_s *arg = pi->check_cb_arg;
ctrl_t ctrl = arg->ctrl;
size_t dummy;
gpg_error_t err;
gnupg_isotime_t now, protected_at, tmptime;
char *desc = NULL;
log_assert (!arg->unprotected_key);
arg->change_required = 0;
err = agent_unprotect (ctrl, arg->protected_key, pi->pin, protected_at,
&arg->unprotected_key, &dummy);
if (err)
return err;
if (!opt.max_passphrase_days || ctrl->in_passwd)
return 0; /* No regular passphrase change required. */
if (!*protected_at)
{
/* No protection date known - must force passphrase change. */
desc = xtrystrdup (L_("Note: This passphrase has never been changed.%0A"
"Please change it now."));
if (!desc)
return gpg_error_from_syserror ();
}
else
{
gnupg_get_isotime (now);
gnupg_copy_time (tmptime, protected_at);
err = add_days_to_isotime (tmptime, opt.max_passphrase_days);
if (err)
return err;
if (strcmp (now, tmptime) > 0 )
{
/* Passphrase "expired". */
desc = xtryasprintf
(L_("This passphrase has not been changed%%0A"
"since %.4s-%.2s-%.2s. Please change it now."),
protected_at, protected_at+4, protected_at+6);
if (!desc)
return gpg_error_from_syserror ();
}
}
if (desc)
{
/* Change required. */
if (opt.enforce_passphrase_constraints)
{
err = agent_get_confirmation (ctrl, desc,
L_("Change passphrase"), NULL, 0);
if (!err)
arg->change_required = 1;
}
else
{
err = agent_get_confirmation (ctrl, desc,
L_("Change passphrase"),
L_("I'll change it later"), 0);
if (!err)
arg->change_required = 1;
else if (gpg_err_code (err) == GPG_ERR_CANCELED
|| gpg_err_code (err) == GPG_ERR_FULLY_CANCELED)
err = 0;
}
xfree (desc);
}
return err;
}
/* Return true if the STRING has an %C or %c expando. */
static int
has_comment_expando (const char *string)
{
const char *s;
int percent = 0;
if (!string)
return 0;
for (s = string; *s; s++)
{
if (percent)
{
if (*s == 'c' || *s == 'C')
return 1;
percent = 0;
}
else if (*s == '%')
percent = 1;
}
return 0;
}
/* Modify a Key description, replacing certain special format
characters. List of currently supported replacements:
%% - Replaced by a single %
%c - Replaced by the content of COMMENT.
%C - Same as %c but put into parentheses.
%F - Replaced by an ssh style fingerprint computed from KEY.
The functions returns 0 on success or an error code. On success a
newly allocated string is stored at the address of RESULT.
*/
gpg_error_t
agent_modify_description (const char *in, const char *comment,
const gcry_sexp_t key, char **result)
{
size_t comment_length;
size_t in_len;
size_t out_len;
char *out;
size_t i;
int special, pass;
char *ssh_fpr = NULL;
char *p;
*result = NULL;
if (!comment)
comment = "";
comment_length = strlen (comment);
in_len = strlen (in);
/* First pass calculates the length, second pass does the actual
copying. */
/* FIXME: This can be simplified by using es_fopenmem. */
out = NULL;
out_len = 0;
for (pass=0; pass < 2; pass++)
{
special = 0;
for (i = 0; i < in_len; i++)
{
if (special)
{
special = 0;
switch (in[i])
{
case '%':
if (out)
*out++ = '%';
else
out_len++;
break;
case 'c': /* Comment. */
if (out)
{
memcpy (out, comment, comment_length);
out += comment_length;
}
else
out_len += comment_length;
break;
case 'C': /* Comment. */
if (!comment_length)
;
else if (out)
{
*out++ = '(';
memcpy (out, comment, comment_length);
out += comment_length;
*out++ = ')';
}
else
out_len += comment_length + 2;
break;
case 'F': /* SSH style fingerprint. */
if (!ssh_fpr && key)
ssh_get_fingerprint_string (key, opt.ssh_fingerprint_digest,
&ssh_fpr);
if (ssh_fpr)
{
if (out)
out = stpcpy (out, ssh_fpr);
else
out_len += strlen (ssh_fpr);
}
break;
default: /* Invalid special sequences are kept as they are. */
if (out)
{
*out++ = '%';
*out++ = in[i];
}
else
out_len+=2;
break;
}
}
else if (in[i] == '%')
special = 1;
else
{
if (out)
*out++ = in[i];
else
out_len++;
}
}
if (!pass)
{
*result = out = xtrymalloc (out_len + 1);
if (!out)
{
xfree (ssh_fpr);
return gpg_error_from_syserror ();
}
}
}
*out = 0;
log_assert (*result + out_len == out);
xfree (ssh_fpr);
/* The ssh prompt may sometimes end in
* "...%0A ()"
* The empty parentheses doesn't look very good. We use this hack
* here to remove them as well as the indentation spaces. */
p = *result;
i = strlen (p);
if (i > 2 && !strcmp (p + i - 2, "()"))
{
p += i - 2;
*p-- = 0;
while (p > *result && spacep (p))
*p-- = 0;
}
return 0;
}
/* Unprotect the canconical encoded S-expression key in KEYBUF. GRIP
should be the hex encoded keygrip of that key to be used with the
caching mechanism. DESC_TEXT may be set to override the default
description used for the pinentry. If LOOKUP_TTL is given this
function is used to lookup the default ttl. If R_PASSPHRASE is not
NULL, the function succeeded and the key was protected the used
passphrase (entered or from the cache) is stored there; if not NULL
will be stored. The caller needs to free the returned
passphrase. */
static gpg_error_t
unprotect (ctrl_t ctrl, const char *cache_nonce, const char *desc_text,
unsigned char **keybuf, const unsigned char *grip,
cache_mode_t cache_mode, lookup_ttl_t lookup_ttl,
char **r_passphrase)
{
struct pin_entry_info_s *pi;
struct try_unprotect_arg_s arg;
int rc;
unsigned char *result;
size_t resultlen;
char hexgrip[40+1];
if (r_passphrase)
*r_passphrase = NULL;
bin2hex (grip, 20, hexgrip);
/* Initially try to get it using a cache nonce. */
if (cache_nonce)
{
char *pw;
pw = agent_get_cache (ctrl, cache_nonce, CACHE_MODE_NONCE);
if (pw)
{
rc = agent_unprotect (ctrl, *keybuf, pw, NULL, &result, &resultlen);
if (!rc)
{
if (r_passphrase)
*r_passphrase = pw;
else
xfree (pw);
xfree (*keybuf);
*keybuf = result;
return 0;
}
xfree (pw);
}
}
/* First try to get it from the cache - if there is none or we can't
unprotect it, we fall back to ask the user */
if (cache_mode != CACHE_MODE_IGNORE)
{
char *pw;
retry:
pw = agent_get_cache (ctrl, hexgrip, cache_mode);
if (pw)
{
rc = agent_unprotect (ctrl, *keybuf, pw, NULL, &result, &resultlen);
if (!rc)
{
if (cache_mode == CACHE_MODE_NORMAL)
agent_store_cache_hit (hexgrip);
if (r_passphrase)
*r_passphrase = pw;
else
xfree (pw);
xfree (*keybuf);
*keybuf = result;
return 0;
}
xfree (pw);
}
else if (cache_mode == CACHE_MODE_NORMAL)
{
/* The standard use of GPG keys is to have a signing and an
encryption subkey. Commonly both use the same
passphrase. We try to help the user to enter the
passphrase only once by silently trying the last
correctly entered passphrase. Checking one additional
passphrase should be acceptable; despite the S2K
introduced delays. The assumed workflow is:
1. Read encrypted message in a MUA and thus enter a
passphrase for the encryption subkey.
2. Reply to that mail with an encrypted and signed
mail, thus entering the passphrase for the signing
subkey.
We can often avoid the passphrase entry in the second
step. We do this only in normal mode, so not to
interfere with unrelated cache entries. */
pw = agent_get_cache (ctrl, NULL, cache_mode);
if (pw)
{
rc = agent_unprotect (ctrl, *keybuf, pw, NULL,
&result, &resultlen);
if (!rc)
{
if (r_passphrase)
*r_passphrase = pw;
else
xfree (pw);
xfree (*keybuf);
*keybuf = result;
return 0;
}
xfree (pw);
}
}
/* If the pinentry is currently in use, we wait up to 60 seconds
for it to close and check the cache again. This solves a common
situation where several requests for unprotecting a key have
been made but the user is still entering the passphrase for
the first request. Because all requests to agent_askpin are
serialized they would then pop up one after the other to
request the passphrase - despite that the user has already
entered it and is then available in the cache. This
implementation is not race free but in the worst case the
user has to enter the passphrase only once more. */
if (pinentry_active_p (ctrl, 0))
{
/* Active - wait */
if (!pinentry_active_p (ctrl, 60))
{
/* We need to give the other thread a chance to actually put
it into the cache. */
gnupg_sleep (1);
goto retry;
}
/* Timeout - better call pinentry now the plain way. */
}
}
pi = gcry_calloc_secure (1, sizeof (*pi) + MAX_PASSPHRASE_LEN + 1);
if (!pi)
return gpg_error_from_syserror ();
pi->max_length = MAX_PASSPHRASE_LEN + 1;
pi->min_digits = 0; /* we want a real passphrase */
pi->max_digits = 16;
pi->max_tries = 3;
pi->check_cb = try_unprotect_cb;
arg.ctrl = ctrl;
arg.protected_key = *keybuf;
arg.unprotected_key = NULL;
arg.change_required = 0;
pi->check_cb_arg = &arg;
rc = agent_askpin (ctrl, desc_text, NULL, NULL, pi, hexgrip, cache_mode);
if (rc)
{
if ((pi->status & PINENTRY_STATUS_PASSWORD_FROM_CACHE))
{
log_error ("Clearing pinentry cache which caused error %s\n",
gpg_strerror (rc));
agent_clear_passphrase (ctrl, hexgrip, cache_mode);
}
}
else
{
log_assert (arg.unprotected_key);
if (arg.change_required)
{
/* The callback told as that the user should change their
passphrase. Present the dialog to do. */
size_t canlen, erroff;
gcry_sexp_t s_skey;
log_assert (arg.unprotected_key);
canlen = gcry_sexp_canon_len (arg.unprotected_key, 0, NULL, NULL);
rc = gcry_sexp_sscan (&s_skey, &erroff,
(char*)arg.unprotected_key, canlen);
if (rc)
{
log_error ("failed to build S-Exp (off=%u): %s\n",
(unsigned int)erroff, gpg_strerror (rc));
wipememory (arg.unprotected_key, canlen);
xfree (arg.unprotected_key);
xfree (pi);
return rc;
}
rc = agent_protect_and_store (ctrl, s_skey, NULL);
gcry_sexp_release (s_skey);
if (rc)
{
log_error ("changing the passphrase failed: %s\n",
gpg_strerror (rc));
wipememory (arg.unprotected_key, canlen);
xfree (arg.unprotected_key);
xfree (pi);
return rc;
}
}
else
{
/* Passphrase is fine. */
agent_put_cache (ctrl, hexgrip, cache_mode, pi->pin,
lookup_ttl? lookup_ttl (hexgrip) : 0);
agent_store_cache_hit (hexgrip);
if (r_passphrase && *pi->pin)
*r_passphrase = xtrystrdup (pi->pin);
}
xfree (*keybuf);
*keybuf = arg.unprotected_key;
}
xfree (pi);
return rc;
}
/* Read the key identified by GRIP from the private key directory and
* return it as an gcrypt S-expression object in RESULT. If R_KEYMETA
* is not NULL and the extended key format is used, the meta data
* items are stored there. However the "Key:" item is removed from
* it. If R_ORIG_KEY_VALUE is non-NULL and the Key item was removed,
* its original value is stored at that R_ORIG_KEY_VALUE and the
* caller must free it. On failure returns an error code and stores
* NULL at RESULT and R_KEYMETA. */
static gpg_error_t
read_key_file (const unsigned char *grip, gcry_sexp_t *result, nvc_t *r_keymeta,
char **r_orig_key_value)
{
gpg_error_t err;
char *fname;
estream_t fp;
struct stat st;
unsigned char *buf;
size_t buflen, erroff;
gcry_sexp_t s_skey;
char first;
*result = NULL;
if (r_keymeta)
*r_keymeta = NULL;
if (r_orig_key_value)
*r_orig_key_value = NULL;
fname = fname_from_keygrip (grip, 0);
if (!fname)
{
return gpg_error_from_syserror ();
}
fp = es_fopen (fname, "rb");
if (!fp)
{
err = gpg_error_from_syserror ();
if (gpg_err_code (err) != GPG_ERR_ENOENT)
log_error ("can't open '%s': %s\n", fname, gpg_strerror (err));
xfree (fname);
return err;
}
if (es_fread (&first, 1, 1, fp) != 1)
{
err = gpg_error_from_syserror ();
log_error ("error reading first byte from '%s': %s\n",
fname, gpg_strerror (err));
xfree (fname);
es_fclose (fp);
return err;
}
if (es_fseek (fp, 0, SEEK_SET))
{
err = gpg_error_from_syserror ();
log_error ("error seeking in '%s': %s\n", fname, gpg_strerror (err));
xfree (fname);
es_fclose (fp);
return err;
}
if (first != '(')
{
/* Key is in extended format. */
nvc_t pk = NULL;
int line;
err = nvc_parse_private_key (&pk, &line, fp);
es_fclose (fp);
if (err)
log_error ("error parsing '%s' line %d: %s\n",
fname, line, gpg_strerror (err));
else
{
err = nvc_get_private_key (pk, result);
if (err)
log_error ("error getting private key from '%s': %s\n",
fname, gpg_strerror (err));
else
{
if (r_orig_key_value)
{
const char *s = nvc_get_string (pk, "Key:");
if (s)
{
*r_orig_key_value = xtrystrdup (s);
if (!*r_orig_key_value)
{
err = gpg_error_from_syserror ();
nvc_release (pk);
xfree (fname);
return err;
}
}
}
nvc_delete_named (pk, "Key:");
}
}
if (!err && r_keymeta)
*r_keymeta = pk;
else
nvc_release (pk);
xfree (fname);
return err;
}
if (fstat (es_fileno (fp), &st))
{
err = gpg_error_from_syserror ();
log_error ("can't stat '%s': %s\n", fname, gpg_strerror (err));
xfree (fname);
es_fclose (fp);
return err;
}
buflen = st.st_size;
buf = xtrymalloc (buflen+1);