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gnupg/g10/keyid.c
NIIBE Yutaka cfc1497efa gpg: Fix compute_fingerprint for ECC with SOS. 
* g10/keyid.c (hash_public_key): Tweak NBITS just as sos_write does.

--

Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
2021-03-12 16:15:04 +09:00

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/* keyid.c - key ID and fingerprint handling
* Copyright (C) 1998, 1999, 2000, 2001, 2003,
* 2004, 2006, 2010 Free Software Foundation, Inc.
* Copyright (C) 2014 Werner Koch
* Copyright (C) 2016 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 <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <time.h>
#include "gpg.h"
#include "../common/util.h"
#include "main.h"
#include "packet.h"
#include "options.h"
#include "keydb.h"
#include "../common/i18n.h"
#include "rmd160.h"
#include "../common/host2net.h"
#define KEYID_STR_SIZE 19
#ifdef HAVE_UNSIGNED_TIME_T
# define IS_INVALID_TIME_T(a) ((a) == (time_t)(-1))
#else
/* Error or 32 bit time_t and value after 2038-01-19. */
# define IS_INVALID_TIME_T(a) ((a) < 0)
#endif
/* Return a letter describing the public key algorithms. */
int
pubkey_letter( int algo )
{
switch (algo)
{
case PUBKEY_ALGO_RSA: return 'R' ;
case PUBKEY_ALGO_RSA_E: return 'r' ;
case PUBKEY_ALGO_RSA_S: return 's' ;
case PUBKEY_ALGO_ELGAMAL_E: return 'g' ;
case PUBKEY_ALGO_ELGAMAL: return 'G' ;
case PUBKEY_ALGO_DSA: return 'D' ;
case PUBKEY_ALGO_ECDH: return 'e' ; /* ECC DH (encrypt only) */
case PUBKEY_ALGO_ECDSA: return 'E' ; /* ECC DSA (sign only) */
case PUBKEY_ALGO_EDDSA: return 'E' ; /* ECC EdDSA (sign only) */
default: return '?';
}
}
/* Return a string describing the public key algorithm and the
keysize. For elliptic curves the function prints the name of the
curve because the keysize is a property of the curve. The string
is copied to the supplied buffer up a length of BUFSIZE-1.
Examples for the output are:
"rsa3072" - RSA with 3072 bit
"elg1024" - Elgamal with 1024 bit
"ed25519" - ECC using the curve Ed25519.
"E_1.2.3.4" - ECC using the unsupported curve with OID "1.2.3.4".
"E_1.3.6.1.4.1.11591.2.12242973" ECC with a bogus OID.
"unknown_N" - Unknown OpenPGP algorithm N.
If the option --legacy-list-mode is active, the output use the
legacy format:
"3072R" - RSA with 3072 bit
"1024g" - Elgamal with 1024 bit
"256E" - ECDSA using a curve with 256 bit
The macro PUBKEY_STRING_SIZE may be used to allocate a buffer with
a suitable size. Note that a more general version of this function
exists as get_keyalgo_string. However, that has no special
treatment for the old and unsupported Elgamal which we here print as
xxxNNNN. */
char *
pubkey_string (PKT_public_key *pk, char *buffer, size_t bufsize)
{
const char *prefix = NULL;
if (opt.legacy_list_mode)
{
snprintf (buffer, bufsize, "%4u%c",
nbits_from_pk (pk), pubkey_letter (pk->pubkey_algo));
return buffer;
}
switch (pk->pubkey_algo)
{
case PUBKEY_ALGO_RSA:
case PUBKEY_ALGO_RSA_E:
case PUBKEY_ALGO_RSA_S: prefix = "rsa"; break;
case PUBKEY_ALGO_ELGAMAL_E: prefix = "elg"; break;
case PUBKEY_ALGO_DSA: prefix = "dsa"; break;
case PUBKEY_ALGO_ELGAMAL: prefix = "xxx"; break;
case PUBKEY_ALGO_ECDH:
case PUBKEY_ALGO_ECDSA:
case PUBKEY_ALGO_EDDSA: prefix = ""; break;
}
if (prefix && *prefix)
snprintf (buffer, bufsize, "%s%u", prefix, nbits_from_pk (pk));
else if (prefix)
{
char *curve = openpgp_oid_to_str (pk->pkey[0]);
const char *name = openpgp_oid_to_curve (curve, 0);
if (name)
snprintf (buffer, bufsize, "%s", name);
else if (curve)
snprintf (buffer, bufsize, "E_%s", curve);
else
snprintf (buffer, bufsize, "E_error");
xfree (curve);
}
else
snprintf (buffer, bufsize, "unknown_%u", (unsigned int)pk->pubkey_algo);
return buffer;
}
/* Hash a public key. This function is useful for v4 and v5
* fingerprints and for v3 or v4 key signing. */
void
hash_public_key (gcry_md_hd_t md, PKT_public_key *pk)
{
unsigned int n;
unsigned int nn[PUBKEY_MAX_NPKEY];
byte *pp[PUBKEY_MAX_NPKEY];
int i;
unsigned int nbits;
size_t nbytes;
int npkey = pubkey_get_npkey (pk->pubkey_algo);
int is_v5 = pk->version == 5;
n = is_v5? 10 : 6;
/* FIXME: We can avoid the extra malloc by calling only the first
mpi_print here which computes the required length and calling the
real mpi_print only at the end. The speed advantage would only be
for ECC (opaque MPIs) or if we could implement an mpi_print
variant with a callback handler to do the hashing. */
if (npkey==0 && pk->pkey[0]
&& gcry_mpi_get_flag (pk->pkey[0], GCRYMPI_FLAG_OPAQUE))
{
pp[0] = gcry_mpi_get_opaque (pk->pkey[0], &nbits);
nn[0] = (nbits+7)/8;
n+=nn[0];
}
else
{
for (i=0; i < npkey; i++ )
{
if (!pk->pkey[i])
{
/* This case may only happen if the parsing of the MPI
failed but the key was anyway created. May happen
during "gpg KEYFILE". */
pp[i] = NULL;
nn[i] = 0;
}
else if (gcry_mpi_get_flag (pk->pkey[i], GCRYMPI_FLAG_OPAQUE))
{
const char *p;
int is_sos = 0;
if (gcry_mpi_get_flag (pk->pkey[i], GCRYMPI_FLAG_USER2))
is_sos = 2;
p = gcry_mpi_get_opaque (pk->pkey[i], &nbits);
pp[i] = xmalloc ((nbits+7)/8 + is_sos);
if (p)
memcpy (pp[i] + is_sos, p, (nbits+7)/8);
else
pp[i] = NULL;
if (is_sos)
{
if (*p)
{
nbits = ((nbits + 7) / 8) * 8;
if (nbits >= 8 && !(*p & 0x80))
if (--nbits >= 7 && !(*p & 0x40))
if (--nbits >= 6 && !(*p & 0x20))
if (--nbits >= 5 && !(*p & 0x10))
if (--nbits >= 4 && !(*p & 0x08))
if (--nbits >= 3 && !(*p & 0x04))
if (--nbits >= 2 && !(*p & 0x02))
if (--nbits >= 1 && !(*p & 0x01))
--nbits;
}
pp[i][0] = (nbits >> 8);
pp[i][1] = nbits;
}
nn[i] = (nbits+7)/8 + is_sos;
n += nn[i];
}
else
{
if (gcry_mpi_print (GCRYMPI_FMT_PGP, NULL, 0,
&nbytes, pk->pkey[i]))
BUG ();
pp[i] = xmalloc (nbytes);
if (gcry_mpi_print (GCRYMPI_FMT_PGP, pp[i], nbytes,
&nbytes, pk->pkey[i]))
BUG ();
nn[i] = nbytes;
n += nn[i];
}
}
}
if (is_v5)
{
gcry_md_putc ( md, 0x9a ); /* ctb */
gcry_md_putc ( md, n >> 24 ); /* 4 byte length header */
gcry_md_putc ( md, n >> 16 );
gcry_md_putc ( md, n >> 8 );
gcry_md_putc ( md, n );
gcry_md_putc ( md, pk->version );
}
else
{
gcry_md_putc ( md, 0x99 ); /* ctb */
gcry_md_putc ( md, n >> 8 ); /* 2 byte length header */
gcry_md_putc ( md, n );
gcry_md_putc ( md, pk->version );
}
gcry_md_putc ( md, pk->timestamp >> 24 );
gcry_md_putc ( md, pk->timestamp >> 16 );
gcry_md_putc ( md, pk->timestamp >> 8 );
gcry_md_putc ( md, pk->timestamp );
gcry_md_putc ( md, pk->pubkey_algo );
if (is_v5)
{
n -= 10;
gcry_md_putc ( md, n >> 24 );
gcry_md_putc ( md, n >> 16 );
gcry_md_putc ( md, n >> 8 );
gcry_md_putc ( md, n );
}
if(npkey==0 && pk->pkey[0]
&& gcry_mpi_get_flag (pk->pkey[0], GCRYMPI_FLAG_OPAQUE))
{
if (pp[0])
gcry_md_write (md, pp[0], nn[0]);
}
else
{
for(i=0; i < npkey; i++ )
{
if (pp[i])
gcry_md_write ( md, pp[i], nn[i] );
xfree(pp[i]);
}
}
}
/* fixme: Check whether we can replace this function or if not
describe why we need it. */
u32
v3_keyid (gcry_mpi_t a, u32 *ki)
{
byte *buffer, *p;
size_t nbytes;
if (gcry_mpi_print (GCRYMPI_FMT_USG, NULL, 0, &nbytes, a ))
BUG ();
/* fixme: allocate it on the stack */
buffer = xmalloc (nbytes);
if (gcry_mpi_print( GCRYMPI_FMT_USG, buffer, nbytes, NULL, a ))
BUG ();
if (nbytes < 8) /* oops */
ki[0] = ki[1] = 0;
else
{
p = buffer + nbytes - 8;
ki[0] = buf32_to_u32 (p);
p += 4;
ki[1] = buf32_to_u32 (p);
}
xfree (buffer);
return ki[1];
}
/* Return PK's keyid. The memory is owned by PK. */
u32 *
pk_keyid (PKT_public_key *pk)
{
keyid_from_pk (pk, NULL);
/* Uncomment this for help tracking down bugs related to keyid or
main_keyid not being set correctly. */
#if 0
if (! (pk->main_keyid[0] || pk->main_keyid[1]))
log_bug ("pk->main_keyid not set!\n");
if (keyid_cmp (pk->keyid, pk->main_keyid) == 0
&& ! pk->flags.primary)
log_bug ("keyid and main_keyid are the same, but primary flag not set!\n");
if (keyid_cmp (pk->keyid, pk->main_keyid) != 0
&& pk->flags.primary)
log_bug ("keyid and main_keyid are different, but primary flag set!\n");
#endif
return pk->keyid;
}
/* Return the keyid of the primary key associated with PK. The memory
is owned by PK. */
u32 *
pk_main_keyid (PKT_public_key *pk)
{
/* Uncomment this for help tracking down bugs related to keyid or
main_keyid not being set correctly. */
#if 0
if (! (pk->main_keyid[0] || pk->main_keyid[1]))
log_bug ("pk->main_keyid not set!\n");
#endif
return pk->main_keyid;
}
/* Copy the keyid in SRC to DEST and return DEST. */
u32 *
keyid_copy (u32 *dest, const u32 *src)
{
dest[0] = src[0];
dest[1] = src[1];
return dest;
}
char *
format_keyid (u32 *keyid, int format, char *buffer, int len)
{
char tmp[KEYID_STR_SIZE];
if (! buffer)
{
buffer = tmp;
len = sizeof (tmp);
}
if (format == KF_DEFAULT)
format = opt.keyid_format;
if (format == KF_DEFAULT)
format = KF_NONE;
switch (format)
{
case KF_NONE:
if (len)
*buffer = 0;
break;
case KF_SHORT:
snprintf (buffer, len, "%08lX", (ulong)keyid[1]);
break;
case KF_LONG:
snprintf (buffer, len, "%08lX%08lX", (ulong)keyid[0], (ulong)keyid[1]);
break;
case KF_0xSHORT:
snprintf (buffer, len, "0x%08lX", (ulong)keyid[1]);
break;
case KF_0xLONG:
snprintf (buffer, len, "0x%08lX%08lX", (ulong)keyid[0],(ulong)keyid[1]);
break;
default:
BUG();
}
if (buffer == tmp)
return xstrdup (buffer);
return buffer;
}
size_t
keystrlen(void)
{
int format = opt.keyid_format;
if (format == KF_DEFAULT)
format = KF_NONE;
switch(format)
{
case KF_NONE:
return 0;
case KF_SHORT:
return 8;
case KF_LONG:
return 16;
case KF_0xSHORT:
return 10;
case KF_0xLONG:
return 18;
default:
BUG();
}
}
const char *
keystr (u32 *keyid)
{
static char keyid_str[KEYID_STR_SIZE];
int format = opt.keyid_format;
if (format == KF_DEFAULT)
format = KF_NONE;
if (format == KF_NONE)
format = KF_LONG;
return format_keyid (keyid, format, keyid_str, sizeof (keyid_str));
}
/* This function returns the key id of the main and possible the
* subkey as one string. It is used by error messages. */
const char *
keystr_with_sub (u32 *main_kid, u32 *sub_kid)
{
static char buffer[KEYID_STR_SIZE+1+KEYID_STR_SIZE];
char *p;
int format = opt.keyid_format;
if (format == KF_NONE)
format = KF_LONG;
format_keyid (main_kid, format, buffer, KEYID_STR_SIZE);
if (sub_kid)
{
p = buffer + strlen (buffer);
*p++ = '/';
format_keyid (sub_kid, format, p, KEYID_STR_SIZE);
}
return buffer;
}
const char *
keystr_from_pk(PKT_public_key *pk)
{
keyid_from_pk(pk,NULL);
return keystr(pk->keyid);
}
const char *
keystr_from_pk_with_sub (PKT_public_key *main_pk, PKT_public_key *sub_pk)
{
keyid_from_pk (main_pk, NULL);
if (sub_pk)
keyid_from_pk (sub_pk, NULL);
return keystr_with_sub (main_pk->keyid, sub_pk? sub_pk->keyid:NULL);
}
/* Return PK's key id as a string using the default format. PK owns
the storage. */
const char *
pk_keyid_str (PKT_public_key *pk)
{
return keystr (pk_keyid (pk));
}
const char *
keystr_from_desc(KEYDB_SEARCH_DESC *desc)
{
switch(desc->mode)
{
case KEYDB_SEARCH_MODE_LONG_KID:
case KEYDB_SEARCH_MODE_SHORT_KID:
return keystr(desc->u.kid);
case KEYDB_SEARCH_MODE_FPR:
{
u32 keyid[2];
if (desc->fprlen == 32)
{
keyid[0] = buf32_to_u32 (desc->u.fpr);
keyid[1] = buf32_to_u32 (desc->u.fpr+4);
}
else if (desc->fprlen == 20)
{
keyid[0] = buf32_to_u32 (desc->u.fpr+12);
keyid[1] = buf32_to_u32 (desc->u.fpr+16);
}
else if (desc->fprlen == 16)
return "?v3 fpr?";
else /* oops */
return "?vx fpr?";
return keystr(keyid);
}
default:
BUG();
}
}
/* Compute the fingerprint and keyid and store it in PK. */
static void
compute_fingerprint (PKT_public_key *pk)
{
const byte *dp;
gcry_md_hd_t md;
size_t len;
if (gcry_md_open (&md, pk->version == 5 ? GCRY_MD_SHA256 : GCRY_MD_SHA1, 0))
BUG ();
hash_public_key (md, pk);
gcry_md_final (md);
dp = gcry_md_read (md, 0);
len = gcry_md_get_algo_dlen (gcry_md_get_algo (md));
log_assert (len <= MAX_FINGERPRINT_LEN);
memcpy (pk->fpr, dp, len);
pk->fprlen = len;
if (pk->version == 5)
{
pk->keyid[0] = buf32_to_u32 (dp);
pk->keyid[1] = buf32_to_u32 (dp+4);
}
else
{
pk->keyid[0] = buf32_to_u32 (dp+12);
pk->keyid[1] = buf32_to_u32 (dp+16);
}
gcry_md_close( md);
}
/*
* Get the keyid from the public key PK and store it at KEYID unless
* this is NULL. Returns the 32 bit short keyid.
*/
u32
keyid_from_pk (PKT_public_key *pk, u32 *keyid)
{
u32 dummy_keyid[2];
if (!keyid)
keyid = dummy_keyid;
if (!pk->fprlen)
compute_fingerprint (pk);
keyid[0] = pk->keyid[0];
keyid[1] = pk->keyid[1];
if (pk->fprlen == 32)
return keyid[0];
else
return keyid[1];
}
/*
* Get the keyid from the fingerprint. This function is simple for
* most keys, but has to do a key lookup for old v3 keys where the
* keyid is not part of the fingerprint.
*/
u32
keyid_from_fingerprint (ctrl_t ctrl, const byte *fprint,
size_t fprint_len, u32 *keyid)
{
u32 dummy_keyid[2];
if( !keyid )
keyid = dummy_keyid;
if (fprint_len != 20 && fprint_len != 32)
{
/* This is special as we have to lookup the key first. */
PKT_public_key pk;
int rc;
memset (&pk, 0, sizeof pk);
rc = get_pubkey_byfprint (ctrl, &pk, NULL, fprint, fprint_len);
if( rc )
{
log_printhex (fprint, fprint_len,
"Oops: keyid_from_fingerprint: no pubkey; fpr:");
keyid[0] = 0;
keyid[1] = 0;
}
else
keyid_from_pk (&pk, keyid);
}
else
{
const byte *dp = fprint;
if (fprint_len == 20) /* v4 key */
{
keyid[0] = buf32_to_u32 (dp+12);
keyid[1] = buf32_to_u32 (dp+16);
}
else /* v5 key */
{
keyid[0] = buf32_to_u32 (dp);
keyid[1] = buf32_to_u32 (dp+4);
}
}
return keyid[1];
}
u32
keyid_from_sig (PKT_signature *sig, u32 *keyid)
{
if( keyid )
{
keyid[0] = sig->keyid[0];
keyid[1] = sig->keyid[1];
}
return sig->keyid[1]; /*FIXME:shortkeyid*/
}
byte *
namehash_from_uid (PKT_user_id *uid)
{
if (!uid->namehash)
{
uid->namehash = xmalloc (20);
if (uid->attrib_data)
rmd160_hash_buffer (uid->namehash, uid->attrib_data, uid->attrib_len);
else
rmd160_hash_buffer (uid->namehash, uid->name, uid->len);
}
return uid->namehash;
}
/*
* Return the number of bits used in PK.
*/
unsigned int
nbits_from_pk (PKT_public_key *pk)
{
return pubkey_nbits (pk->pubkey_algo, pk->pkey);
}
/* Convert an UTC TIMESTAMP into an UTC yyyy-mm-dd string. Return
* that string. The caller should pass a buffer with at least a size
* of MK_DATESTR_SIZE. */
char *
mk_datestr (char *buffer, size_t bufsize, u32 timestamp)
{
time_t atime = timestamp;
struct tm *tp;
if (IS_INVALID_TIME_T (atime))
strcpy (buffer, "????" "-??" "-??"); /* Mark this as invalid. */
else
{
tp = gmtime (&atime);
snprintf (buffer, bufsize, "%04d-%02d-%02d",
1900+tp->tm_year, tp->tm_mon+1, tp->tm_mday );
}
return buffer;
}
/*
* return a string with the creation date of the pk
* Note: this is alloced in a static buffer.
* Format is: yyyy-mm-dd
*/
const char *
dateonlystr_from_pk (PKT_public_key *pk)
{
static char buffer[MK_DATESTR_SIZE];
return mk_datestr (buffer, sizeof buffer, pk->timestamp);
}
/* Same as dateonlystr_from_pk but with a global option a full iso
* timestamp is returned. In this case it shares a static buffer with
* isotimestamp(). */
const char *
datestr_from_pk (PKT_public_key *pk)
{
if (opt.flags.full_timestrings)
return isotimestamp (pk->timestamp);
else
return dateonlystr_from_pk (pk);
}
const char *
dateonlystr_from_sig (PKT_signature *sig )
{
static char buffer[MK_DATESTR_SIZE];
return mk_datestr (buffer, sizeof buffer, sig->timestamp);
}
const char *
datestr_from_sig (PKT_signature *sig )
{
if (opt.flags.full_timestrings)
return isotimestamp (sig->timestamp);
else
return dateonlystr_from_sig (sig);
}
const char *
expirestr_from_pk (PKT_public_key *pk)
{
static char buffer[MK_DATESTR_SIZE];
if (!pk->expiredate)
return _("never ");
if (opt.flags.full_timestrings)
return isotimestamp (pk->expiredate);
return mk_datestr (buffer, sizeof buffer, pk->expiredate);
}
const char *
expirestr_from_sig (PKT_signature *sig)
{
static char buffer[MK_DATESTR_SIZE];
if (!sig->expiredate)
return _("never ");
if (opt.flags.full_timestrings)
return isotimestamp (sig->expiredate);
return mk_datestr (buffer, sizeof buffer, sig->expiredate);
}
const char *
revokestr_from_pk( PKT_public_key *pk )
{
static char buffer[MK_DATESTR_SIZE];
if(!pk->revoked.date)
return _("never ");
if (opt.flags.full_timestrings)
return isotimestamp (pk->revoked.date);
return mk_datestr (buffer, sizeof buffer, pk->revoked.date);
}
const char *
usagestr_from_pk (PKT_public_key *pk, int fill)
{
static char buffer[10];
int i = 0;
unsigned int use = pk->pubkey_usage;
if ( use & PUBKEY_USAGE_SIG )
buffer[i++] = 'S';
if ( use & PUBKEY_USAGE_CERT )
buffer[i++] = 'C';
if ( use & PUBKEY_USAGE_ENC )
buffer[i++] = 'E';
if ( (use & PUBKEY_USAGE_AUTH) )
buffer[i++] = 'A';
while (fill && i < 4)
buffer[i++] = ' ';
buffer[i] = 0;
return buffer;
}
const char *
colon_strtime (u32 t)
{
static char buf[20];
if (!t)
return "";
snprintf (buf, sizeof buf, "%lu", (ulong)t);
return buf;
}
const char *
colon_datestr_from_pk (PKT_public_key *pk)
{
static char buf[20];
snprintf (buf, sizeof buf, "%lu", (ulong)pk->timestamp);
return buf;
}
const char *
colon_datestr_from_sig (PKT_signature *sig)
{
static char buf[20];
snprintf (buf, sizeof buf, "%lu", (ulong)sig->timestamp);
return buf;
}
const char *
colon_expirestr_from_sig (PKT_signature *sig)
{
static char buf[20];
if (!sig->expiredate)
return "";
snprintf (buf, sizeof buf,"%lu", (ulong)sig->expiredate);
return buf;
}
/*
* Return a byte array with the fingerprint for the given PK/SK
* The length of the array is returned in ret_len. Caller must free
* the array or provide an array of length MAX_FINGERPRINT_LEN.
*/
byte *
fingerprint_from_pk (PKT_public_key *pk, byte *array, size_t *ret_len)
{
if (!pk->fprlen)
compute_fingerprint (pk);
if (!array)
array = xmalloc (pk->fprlen);
memcpy (array, pk->fpr, pk->fprlen);
if (ret_len)
*ret_len = pk->fprlen;
return array;
}
/*
* Get FPR20 for the given PK/SK into ARRAY.
*
* FPR20 is special form of fingerprint of length 20 for the record of
* trustdb. For v4key, having fingerprint with SHA-1, FPR20 is the
* same one. For v5key, FPR20 is constructed from its fingerprint
* with SHA-2, so that its kid of last 8-byte can be as same as
* kid of v5key fingerprint.
*
*/
void
fpr20_from_pk (PKT_public_key *pk, byte array[20])
{
if (!pk->fprlen)
compute_fingerprint (pk);
if (!array)
array = xmalloc (pk->fprlen);
if (pk->fprlen == 32) /* v5 fingerprint */
{
memcpy (array + 0, pk->fpr + 20, 4);
memcpy (array + 4, pk->fpr + 24, 4);
memcpy (array + 8, pk->fpr + 28, 4);
memcpy (array + 12, pk->fpr + 0, 4); /* kid[0] */
memcpy (array + 16, pk->fpr + 4, 4); /* kid[1] */
}
else /* v4 fingerprint */
memcpy (array, pk->fpr, 20);
}
/* Return an allocated buffer with the fingerprint of PK formatted as
* a plain hexstring. If BUFFER is NULL the result is a malloc'd
* string. If BUFFER is not NULL the result will be copied into this
* buffer. In the latter case BUFLEN describes the length of the
* buffer; if this is too short the function terminates the process.
* Returns a malloc'ed string or BUFFER. A suitable length for BUFFER
* is (2*MAX_FINGERPRINT_LEN + 1). */
char *
hexfingerprint (PKT_public_key *pk, char *buffer, size_t buflen)
{
if (!pk->fprlen)
compute_fingerprint (pk);
if (!buffer)
{
buffer = xtrymalloc (2 * pk->fprlen + 1);
if (!buffer)
return NULL;
}
else if (buflen < 2 * pk->fprlen + 1)
log_fatal ("%s: buffer too short (%zu)\n", __func__, buflen);
bin2hex (pk->fpr, pk->fprlen, buffer);
return buffer;
}
/* Pretty print a hex fingerprint. If BUFFER is NULL the result is a
malloc'd string. If BUFFER is not NULL the result will be copied
into this buffer. In the latter case BUFLEN describes the length
of the buffer; if this is too short the function terminates the
process. Returns a malloc'ed string or BUFFER. A suitable length
for BUFFER is (MAX_FORMATTED_FINGERPRINT_LEN + 1). */
char *
format_hexfingerprint (const char *fingerprint, char *buffer, size_t buflen)
{
int hexlen = strlen (fingerprint);
int space;
int i, j;
if (hexlen == 40) /* v4 fingerprint */
{
space = (/* The characters and the NUL. */
40 + 1
/* After every fourth character, we add a space (except
the last). */
+ 40 / 4 - 1
/* Half way through we add a second space. */
+ 1);
}
else if (hexlen == 64 || hexlen == 50) /* v5 fingerprint */
{
/* The v5 fingerprint is commonly printed truncated to 25
* octets. We accept the truncated as well as the full hex
* version here and format it like this:
* 19347 BC987 24640 25F99 DF3EC 2E000 0ED98 84892 E1F7B 3EA4C
*/
hexlen = 50;
space = 10 * 5 + 9 + 1;
}
else /* Other fingerprint versions - print as is. */
{
/* We truncated here so that we do not need to provide a buffer
* of a length which is in reality never used. */
if (hexlen > MAX_FORMATTED_FINGERPRINT_LEN - 1)
hexlen = MAX_FORMATTED_FINGERPRINT_LEN - 1;
space = hexlen + 1;
}
if (!buffer)
buffer = xmalloc (space);
else if (buflen < space)
log_fatal ("%s: buffer too short (%zu)\n", __func__, buflen);
if (hexlen == 40) /* v4 fingerprint */
{
for (i = 0, j = 0; i < 40; i ++)
{
if (i && !(i % 4))
buffer[j ++] = ' ';
if (i == 40 / 2)
buffer[j ++] = ' ';
buffer[j ++] = fingerprint[i];
}
buffer[j ++] = 0;
log_assert (j == space);
}
else if (hexlen == 50) /* v5 fingerprint */
{
for (i=j=0; i < 50; i++)
{
if (i && !(i % 5))
buffer[j++] = ' ';
buffer[j++] = fingerprint[i];
}
buffer[j++] = 0;
log_assert (j == space);
}
else
{
mem2str (buffer, fingerprint, space);
}
return buffer;
}
/* Return the so called KEYGRIP which is the SHA-1 hash of the public
key parameters expressed as an canonical encoded S-Exp. ARRAY must
be 20 bytes long. Returns 0 on success or an error code. */
gpg_error_t
keygrip_from_pk (PKT_public_key *pk, unsigned char *array)
{
gpg_error_t err;
gcry_sexp_t s_pkey;
if (DBG_PACKET)
log_debug ("get_keygrip for public key\n");
switch (pk->pubkey_algo)
{
case GCRY_PK_DSA:
err = gcry_sexp_build (&s_pkey, NULL,
"(public-key(dsa(p%m)(q%m)(g%m)(y%m)))",
pk->pkey[0], pk->pkey[1],
pk->pkey[2], pk->pkey[3]);
break;
case GCRY_PK_ELG:
case GCRY_PK_ELG_E:
err = gcry_sexp_build (&s_pkey, NULL,
"(public-key(elg(p%m)(g%m)(y%m)))",
pk->pkey[0], pk->pkey[1], pk->pkey[2]);
break;
case GCRY_PK_RSA:
case GCRY_PK_RSA_S:
case GCRY_PK_RSA_E:
err = gcry_sexp_build (&s_pkey, NULL,
"(public-key(rsa(n%m)(e%m)))",
pk->pkey[0], pk->pkey[1]);
break;
case PUBKEY_ALGO_EDDSA:
case PUBKEY_ALGO_ECDSA:
case PUBKEY_ALGO_ECDH:
{
char *curve = openpgp_oid_to_str (pk->pkey[0]);
if (!curve)
err = gpg_error_from_syserror ();
else
{
err = gcry_sexp_build (&s_pkey, NULL,
pk->pubkey_algo == PUBKEY_ALGO_EDDSA?
"(public-key(ecc(curve%s)(flags eddsa)(q%m)))":
(pk->pubkey_algo == PUBKEY_ALGO_ECDH
&& openpgp_oid_is_cv25519 (pk->pkey[0]))?
"(public-key(ecc(curve%s)(flags djb-tweak)(q%m)))":
"(public-key(ecc(curve%s)(q%m)))",
curve, pk->pkey[1]);
xfree (curve);
}
}
break;
default:
err = gpg_error (GPG_ERR_PUBKEY_ALGO);
break;
}
if (err)
return err;
if (!gcry_pk_get_keygrip (s_pkey, array))
{
char *hexfpr;
hexfpr = hexfingerprint (pk, NULL, 0);
log_info ("error computing keygrip (fpr=%s)\n", hexfpr);
xfree (hexfpr);
memset (array, 0, 20);
err = gpg_error (GPG_ERR_GENERAL);
}
else
{
if (DBG_PACKET)
log_printhex (array, 20, "keygrip=");
/* FIXME: Save the keygrip in PK. */
}
gcry_sexp_release (s_pkey);
return err;
}
/* Store an allocated buffer with the keygrip of PK encoded as a
hexstring at r_GRIP. Returns 0 on success. */
gpg_error_t
hexkeygrip_from_pk (PKT_public_key *pk, char **r_grip)
{
gpg_error_t err;
unsigned char grip[KEYGRIP_LEN];
*r_grip = NULL;
err = keygrip_from_pk (pk, grip);
if (!err)
{
char * buf = xtrymalloc (KEYGRIP_LEN * 2 + 1);
if (!buf)
err = gpg_error_from_syserror ();
else
{
bin2hex (grip, KEYGRIP_LEN, buf);
*r_grip = buf;
}
}
return err;
}
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