/* 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 . */ #include #include #include #include #include #include #include "gpg.h" #include "util.h" #include "main.h" #include "packet.h" #include "options.h" #include "keydb.h" #include "i18n.h" #include "rmd160.h" #include "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 functions 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: "rsa2048" - RSA with 2048 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: "2048R" - RSA with 2048 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.*/ 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 fingerprints and for v3 or v4 key signing. */ void hash_public_key (gcry_md_hd_t md, PKT_public_key *pk) { unsigned int n = 6; 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); /* 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 void *p; p = gcry_mpi_get_opaque (pk->pkey[i], &nbits); pp[i] = xmalloc ((nbits+7)/8); if (p) memcpy (pp[i], p, (nbits+7)/8); else pp[i] = NULL; nn[i] = (nbits+7)/8; 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]; } } } gcry_md_putc ( md, 0x99 ); /* ctb */ /* What does it mean if n is greater than than 0xFFFF ? */ 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(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]); } } } static gcry_md_hd_t do_fingerprint_md( PKT_public_key *pk ) { gcry_md_hd_t md; if (gcry_md_open (&md, DIGEST_ALGO_SHA1, 0)) BUG (); hash_public_key(md,pk); gcry_md_final( md ); return md; } /* 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_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_FPR20: { u32 keyid[2]; keyid[0] = buf32_to_u32 (desc->u.fpr+12); keyid[1] = buf32_to_u32 (desc->u.fpr+16); return keystr(keyid); } case KEYDB_SEARCH_MODE_FPR16: return "?v3 fpr?"; default: BUG(); } } /* * Get the keyid from the public key and put it into keyid * if this is not NULL. Return the 32 low bits of the keyid. */ u32 keyid_from_pk (PKT_public_key *pk, u32 *keyid) { u32 lowbits; u32 dummy_keyid[2]; if (!keyid) keyid = dummy_keyid; if( pk->keyid[0] || pk->keyid[1] ) { keyid[0] = pk->keyid[0]; keyid[1] = pk->keyid[1]; lowbits = keyid[1]; } else { const byte *dp; gcry_md_hd_t md; md = do_fingerprint_md(pk); if(md) { dp = gcry_md_read ( md, 0 ); keyid[0] = buf32_to_u32 (dp+12); keyid[1] = buf32_to_u32 (dp+16); lowbits = keyid[1]; gcry_md_close (md); pk->keyid[0] = keyid[0]; pk->keyid[1] = keyid[1]; } else pk->keyid[0]=pk->keyid[1]=keyid[0]=keyid[1]=lowbits=0xFFFFFFFF; } return lowbits; } /* * Get the keyid from the fingerprint. This function is simple for most * keys, but has to do a keylookup for old stayle keys. */ u32 keyid_from_fingerprint( const byte *fprint, size_t fprint_len, u32 *keyid ) { u32 dummy_keyid[2]; if( !keyid ) keyid = dummy_keyid; if (fprint_len != 20) { /* 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 (&pk, NULL, fprint, fprint_len); if( rc ) { log_error("Oops: keyid_from_fingerprint: no pubkey\n"); keyid[0] = 0; keyid[1] = 0; } else keyid_from_pk (&pk, keyid); } else { const byte *dp = fprint; keyid[0] = buf32_to_u32 (dp+12); keyid[1] = buf32_to_u32 (dp+16); } 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]; } 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); } static const char * mk_datestr (char *buffer, time_t atime) { struct tm *tp; if (IS_INVALID_TIME_T (atime)) strcpy (buffer, "????" "-??" "-??"); /* Mark this as invalid. */ else { tp = gmtime (&atime); sprintf (buffer,"%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 * datestr_from_pk (PKT_public_key *pk) { static char buffer[11+5]; time_t atime = pk->timestamp; return mk_datestr (buffer, atime); } const char * datestr_from_sig (PKT_signature *sig ) { static char buffer[11+5]; time_t atime = sig->timestamp; return mk_datestr (buffer, atime); } const char * expirestr_from_pk (PKT_public_key *pk) { static char buffer[11+5]; time_t atime; if (!pk->expiredate) return _("never "); atime = pk->expiredate; return mk_datestr (buffer, atime); } const char * expirestr_from_sig (PKT_signature *sig) { static char buffer[11+5]; time_t atime; if (!sig->expiredate) return _("never "); atime=sig->expiredate; return mk_datestr (buffer, atime); } const char * revokestr_from_pk( PKT_public_key *pk ) { static char buffer[11+5]; time_t atime; if(!pk->revoked.date) return _("never "); atime=pk->revoked.date; return mk_datestr (buffer, atime); } 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) { const byte *dp; size_t len; gcry_md_hd_t md; md = do_fingerprint_md(pk); dp = gcry_md_read( md, 0 ); len = gcry_md_get_algo_dlen (gcry_md_get_algo (md)); log_assert( len <= MAX_FINGERPRINT_LEN ); if (!array) array = xmalloc ( len ); memcpy (array, dp, len ); pk->keyid[0] = buf32_to_u32 (dp+12); pk->keyid[1] = buf32_to_u32 (dp+16); gcry_md_close( md); if (ret_len) *ret_len = len; return array; } /* 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) { unsigned char fpr[MAX_FINGERPRINT_LEN]; size_t len; fingerprint_from_pk (pk, fpr, &len); if (!buffer) buffer = xmalloc (2 * len + 1); else if (buflen < 2*len+1) log_fatal ("%s: buffer too short (%zu)\n", __func__, buflen); bin2hex (fpr, len, 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 /* Other fingerprint versions - print as is. */ { 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 == 0) buffer[j ++] = ' '; if (i == 40 / 2) buffer[j ++] = ' '; buffer[j ++] = fingerprint[i]; } buffer[j ++] = 0; log_assert (j == space); } else { strcpy (buffer, fingerprint); } return buffer; } /* Return the so called KEYGRIP which is the SHA-1 hash of the public key parameters expressed as an canoncial 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_crv25519 (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)) { log_info ("error computing keygrip\n"); memset (array, 0, 20); err = gpg_error (GPG_ERR_GENERAL); } else { if (DBG_PACKET) log_printhex ("keygrip=", array, 20); /* 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[20]; *r_grip = NULL; err = keygrip_from_pk (pk, grip); if (!err) { char * buf = xtrymalloc (20*2+1); if (!buf) err = gpg_error_from_syserror (); else { bin2hex (grip, 20, buf); *r_grip = buf; } } return err; }