/* sign.c - sign data * Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc. * * 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 2 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, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA */ #include #include #include #include #include #include #include /* need sleep() */ #include "options.h" #include "packet.h" #include "errors.h" #include "iobuf.h" #include "keydb.h" #include "memory.h" #include "util.h" #include "main.h" #include "filter.h" #include "ttyio.h" #include "trustdb.h" #include "status.h" #include "i18n.h" #ifdef HAVE_DOSISH_SYSTEM #define LF "\r\n" void __stdcall Sleep(ulong); #define sleep(a) Sleep((a)*1000) #else #define LF "\n" #endif /**************** * Create a notation. It is assumed that the stings in STRLIST * are already checked to contain only printable data and have a valid * NAME=VALUE format. */ static void mk_notation_and_policy( PKT_signature *sig, PKT_public_key *pk ) { const char *string; char *s=NULL; byte *buf; unsigned n1, n2; STRLIST nd=NULL,pu=NULL; /* notation data */ if(IS_SIG(sig) && opt.sig_notation_data) { if(sig->version<4) log_info("can't put notation data into v3 signatures\n"); else nd=opt.sig_notation_data; } else if( IS_CERT(sig) && opt.cert_notation_data ) { if(sig->version<4) log_info("can't put notation data into v3 key signatures\n"); else nd=opt.cert_notation_data; } for( ; nd; nd = nd->next ) { string = nd->d; s = strchr( string, '=' ); if( !s ) BUG(); /* we have already parsed this */ n1 = s - string; s++; n2 = strlen(s); buf = m_alloc( 8 + n1 + n2 ); buf[0] = 0x80; /* human readable */ buf[1] = buf[2] = buf[3] = 0; buf[4] = n1 >> 8; buf[5] = n1; buf[6] = n2 >> 8; buf[7] = n2; memcpy(buf+8, string, n1 ); memcpy(buf+8+n1, s, n2 ); build_sig_subpkt( sig, SIGSUBPKT_NOTATION | ((nd->flags & 1)? SIGSUBPKT_FLAG_CRITICAL:0), buf, 8+n1+n2 ); } if(opt.show_notation) show_notation(sig,0); /* set policy URL */ if( IS_SIG(sig) && opt.sig_policy_url ) { if(sig->version<4) log_info("can't put a policy URL into v3 signatures\n"); else pu=opt.sig_policy_url; } else if( IS_CERT(sig) && opt.cert_policy_url ) { if(sig->version<4) log_info("can't put a policy URL into v3 key signatures\n"); else pu=opt.cert_policy_url; } for(;pu;pu=pu->next) { string = pu->d; if(pk) { s=pct_expando(string,pk); if(!s) { log_error(_("WARNING: unable to %%-expand policy url " "(too large). Using unexpanded.\n")); s=m_strdup(string); } } else s=m_strdup(string); build_sig_subpkt(sig,SIGSUBPKT_POLICY| ((pu->flags & 1)?SIGSUBPKT_FLAG_CRITICAL:0), s,strlen(s)); m_free(s); } if(opt.show_policy_url) show_policy_url(sig,0); } /* * Helper to hash a user ID packet. */ static void hash_uid (MD_HANDLE md, int sigversion, const PKT_user_id *uid) { if ( sigversion >= 4 ) { byte buf[5]; if(uid->attrib_data) { buf[0] = 0xd1; /* indicates an attribute packet */ buf[1] = uid->attrib_len >> 24; /* always use 4 length bytes */ buf[2] = uid->attrib_len >> 16; buf[3] = uid->attrib_len >> 8; buf[4] = uid->attrib_len; } else { buf[0] = 0xb4; /* indicates a userid packet */ buf[1] = uid->len >> 24; /* always use 4 length bytes */ buf[2] = uid->len >> 16; buf[3] = uid->len >> 8; buf[4] = uid->len; } md_write( md, buf, 5 ); } if(uid->attrib_data) md_write (md, uid->attrib_data, uid->attrib_len ); else md_write (md, uid->name, uid->len ); } /* * Helper to hash some parts from the signature */ static void hash_sigversion_to_magic (MD_HANDLE md, const PKT_signature *sig) { if (sig->version >= 4) md_putc (md, sig->version); md_putc (md, sig->sig_class); if (sig->version < 4) { u32 a = sig->timestamp; md_putc (md, (a >> 24) & 0xff ); md_putc (md, (a >> 16) & 0xff ); md_putc (md, (a >> 8) & 0xff ); md_putc (md, a & 0xff ); } else { byte buf[6]; size_t n; md_putc (md, sig->pubkey_algo); md_putc (md, sig->digest_algo); if (sig->hashed) { n = sig->hashed->len; md_putc (md, (n >> 8) ); md_putc (md, n ); md_write (md, sig->hashed->data, n ); n += 6; } else { md_putc (md, 0); /* always hash the length of the subpacket*/ md_putc (md, 0); n = 6; } /* add some magic */ buf[0] = sig->version; buf[1] = 0xff; buf[2] = n >> 24; /* hmmm, n is only 16 bit, so this is always 0 */ buf[3] = n >> 16; buf[4] = n >> 8; buf[5] = n; md_write (md, buf, 6); } } static int do_sign( PKT_secret_key *sk, PKT_signature *sig, MD_HANDLE md, int digest_algo ) { MPI frame; byte *dp; int rc; if( sk->timestamp > sig->timestamp ) { ulong d = sk->timestamp - sig->timestamp; log_info( d==1 ? _("key has been created %lu second " "in future (time warp or clock problem)\n") : _("key has been created %lu seconds " "in future (time warp or clock problem)\n"), d ); if( !opt.ignore_time_conflict ) return G10ERR_TIME_CONFLICT; } print_pubkey_algo_note(sk->pubkey_algo); if( !digest_algo ) digest_algo = md_get_algo(md); print_digest_algo_note( digest_algo ); dp = md_read( md, digest_algo ); sig->digest_algo = digest_algo; sig->digest_start[0] = dp[0]; sig->digest_start[1] = dp[1]; frame = encode_md_value( sk->pubkey_algo, md, digest_algo, mpi_get_nbits(sk->skey[0]), 0 ); if (!frame) return G10ERR_GENERAL; rc = pubkey_sign( sk->pubkey_algo, sig->data, frame, sk->skey ); mpi_free(frame); if (!rc && !opt.no_sig_create_check) { /* check that the signature verification worked and nothing is * fooling us e.g. by a bug in the signature create * code or by deliberately introduced faults. */ PKT_public_key *pk = m_alloc_clear (sizeof *pk); if( get_pubkey( pk, sig->keyid ) ) rc = G10ERR_NO_PUBKEY; else { frame = encode_md_value (pk->pubkey_algo, md, sig->digest_algo, mpi_get_nbits(pk->pkey[0]), 0); if (!frame) rc = G10ERR_GENERAL; else rc = pubkey_verify (pk->pubkey_algo, frame, sig->data, pk->pkey, NULL, NULL ); mpi_free (frame); } if (rc) log_error (_("checking created signature failed: %s\n"), g10_errstr (rc)); free_public_key (pk); } if( rc ) log_error(_("signing failed: %s\n"), g10_errstr(rc) ); else { if( opt.verbose ) { char *ustr = get_user_id_string( sig->keyid ); log_info(_("%s signature from: %s\n"), pubkey_algo_to_string(sk->pubkey_algo), ustr ); m_free(ustr); } } return rc; } int complete_sig( PKT_signature *sig, PKT_secret_key *sk, MD_HANDLE md ) { int rc=0; if( !(rc=check_secret_key( sk, 0 )) ) rc = do_sign( sk, sig, md, 0 ); return rc; } static int hash_for(int pubkey_algo, int packet_version ) { if( opt.def_digest_algo ) return opt.def_digest_algo; if( pubkey_algo == PUBKEY_ALGO_DSA ) return DIGEST_ALGO_SHA1; if( pubkey_algo == PUBKEY_ALGO_RSA && packet_version < 4 ) return DIGEST_ALGO_MD5; return DEFAULT_DIGEST_ALGO; } static int only_old_style( SK_LIST sk_list ) { SK_LIST sk_rover = NULL; int old_style = 0; /* if there are only old style capable key we use the old sytle */ for( sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next ) { PKT_secret_key *sk = sk_rover->sk; if( sk->pubkey_algo == PUBKEY_ALGO_RSA && sk->version < 4 ) old_style = 1; else return 0; } return old_style; } static void print_status_sig_created ( PKT_secret_key *sk, PKT_signature *sig, int what ) { byte array[MAX_FINGERPRINT_LEN], *p; char buf[100+MAX_FINGERPRINT_LEN*2]; size_t i, n; sprintf(buf, "%c %d %d %02x %lu ", what, sig->pubkey_algo, sig->digest_algo, sig->sig_class, (ulong)sig->timestamp ); fingerprint_from_sk( sk, array, &n ); p = buf + strlen(buf); for(i=0; i < n ; i++ ) sprintf(p+2*i, "%02X", array[i] ); write_status_text( STATUS_SIG_CREATED, buf ); } /* * Loop over the secret certificates in SK_LIST and build the one pass * signature packets. OpenPGP says that the data should be bracket by * the onepass-sig and signature-packet; so we build these onepass * packet here in reverse order */ static int write_onepass_sig_packets (SK_LIST sk_list, IOBUF out, int sigclass ) { int skcount; SK_LIST sk_rover; for (skcount=0, sk_rover=sk_list; sk_rover; sk_rover = sk_rover->next) skcount++; for (; skcount; skcount--) { PKT_secret_key *sk; PKT_onepass_sig *ops; PACKET pkt; int i, rc; for (i=0, sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next ) { if (++i == skcount) break; } sk = sk_rover->sk; ops = m_alloc_clear (sizeof *ops); ops->sig_class = sigclass; ops->digest_algo = hash_for (sk->pubkey_algo, sk->version); ops->pubkey_algo = sk->pubkey_algo; keyid_from_sk (sk, ops->keyid); ops->last = (skcount == 1); init_packet(&pkt); pkt.pkttype = PKT_ONEPASS_SIG; pkt.pkt.onepass_sig = ops; rc = build_packet (out, &pkt); free_packet (&pkt); if (rc) { log_error ("build onepass_sig packet failed: %s\n", g10_errstr(rc)); return rc; } } return 0; } /* * Helper to write the plaintext (literal data) packet */ static int write_plaintext_packet (IOBUF out, IOBUF inp, const char *fname, int ptmode) { PKT_plaintext *pt = NULL; u32 filesize; int rc = 0; if (!opt.no_literal) { if (fname || opt.set_filename) { char *s = make_basename (opt.set_filename? opt.set_filename : fname); pt = m_alloc (sizeof *pt + strlen(s) - 1); pt->namelen = strlen (s); memcpy (pt->name, s, pt->namelen); m_free (s); } else { /* no filename */ pt = m_alloc (sizeof *pt - 1); pt->namelen = 0; } } /* try to calculate the length of the data */ if (fname) { if( !(filesize = iobuf_get_filelength(inp)) ) log_info (_("WARNING: `%s' is an empty file\n"), fname); /* we can't yet encode the length of very large files, * so we switch to partial length encoding in this case */ if (filesize >= IOBUF_FILELENGTH_LIMIT) filesize = 0; /* because the text_filter modifies the length of the * data, it is not possible to know the used length * without a double read of the file - to avoid that * we simple use partial length packets. */ if ( ptmode == 't' ) filesize = 0; } else { filesize = opt.set_filesize? opt.set_filesize : 0; /* stdin */ } if (!opt.no_literal) { PACKET pkt; pt->timestamp = make_timestamp (); pt->mode = ptmode; pt->len = filesize; pt->new_ctb = !pt->len && !opt.rfc1991; pt->buf = inp; init_packet(&pkt); pkt.pkttype = PKT_PLAINTEXT; pkt.pkt.plaintext = pt; /*cfx.datalen = filesize? calc_packet_length( &pkt ) : 0;*/ if( (rc = build_packet (out, &pkt)) ) log_error ("build_packet(PLAINTEXT) failed: %s\n", g10_errstr(rc) ); pt->buf = NULL; } else { byte copy_buffer[4096]; int bytes_copied; while ((bytes_copied = iobuf_read(inp, copy_buffer, 4096)) != -1) if (iobuf_write(out, copy_buffer, bytes_copied) == -1) { rc = G10ERR_WRITE_FILE; log_error ("copying input to output failed: %s\n", g10_errstr(rc)); break; } memset(copy_buffer, 0, 4096); /* burn buffer */ } /* fixme: it seems that we never freed pt/pkt */ return rc; } /* * Write the signatures from the SK_LIST to OUT. HASH must be a non-finalized * hash which will not be changes here. */ static int write_signature_packets (SK_LIST sk_list, IOBUF out, MD_HANDLE hash, int sigclass, u32 timestamp, u32 duration, int old_style, int status_letter) { SK_LIST sk_rover; /* loop over the secret certificates */ for (sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next) { PKT_secret_key *sk; PKT_signature *sig; MD_HANDLE md; int rc; sk = sk_rover->sk; /* build the signature packet */ sig = m_alloc_clear (sizeof *sig); if(old_style || opt.force_v3_sigs) sig->version=3; else if(duration) sig->version=4; else sig->version=sk->version; keyid_from_sk (sk, sig->keyid); sig->digest_algo = hash_for (sk->pubkey_algo, sk->version); sig->pubkey_algo = sk->pubkey_algo; if(timestamp) sig->timestamp = timestamp; else sig->timestamp = make_timestamp(); if(duration) sig->expiredate = sig->timestamp+duration; sig->sig_class = sigclass; md = md_copy (hash); if (sig->version >= 4) build_sig_subpkt_from_sig (sig); mk_notation_and_policy (sig, NULL); hash_sigversion_to_magic (md, sig); md_final (md); rc = do_sign( sk, sig, md, hash_for (sig->pubkey_algo, sk->version) ); md_close (md); if( !rc ) { /* and write it */ PACKET pkt; init_packet(&pkt); pkt.pkttype = PKT_SIGNATURE; pkt.pkt.signature = sig; rc = build_packet (out, &pkt); if (!rc && is_status_enabled()) { print_status_sig_created ( sk, sig, status_letter); } free_packet (&pkt); if (rc) log_error ("build signature packet failed: %s\n", g10_errstr(rc) ); } if( rc ) return rc;; } return 0; } /**************** * Sign the files whose names are in FILENAME. * If DETACHED has the value true, * make a detached signature. If FILENAMES->d is NULL read from stdin * and ignore the detached mode. Sign the file with all secret keys * which can be taken from LOCUSR, if this is NULL, use the default one * If ENCRYPTFLAG is true, use REMUSER (or ask if it is NULL) to encrypt the * signed data for these users. * If OUTFILE is not NULL; this file is used for output and the function * does not ask for overwrite permission; output is then always * uncompressed, non-armored and in binary mode. */ int sign_file( STRLIST filenames, int detached, STRLIST locusr, int encryptflag, STRLIST remusr, const char *outfile ) { const char *fname; armor_filter_context_t afx; compress_filter_context_t zfx; md_filter_context_t mfx; text_filter_context_t tfx; encrypt_filter_context_t efx; IOBUF inp = NULL, out = NULL; PACKET pkt; int rc = 0; PK_LIST pk_list = NULL; SK_LIST sk_list = NULL; SK_LIST sk_rover = NULL; int multifile = 0; int old_style = opt.rfc1991; int compr_algo = -1; /* unknown */ u32 timestamp=0,duration=0; memset( &afx, 0, sizeof afx); memset( &zfx, 0, sizeof zfx); memset( &mfx, 0, sizeof mfx); memset( &tfx, 0, sizeof tfx); memset( &efx, 0, sizeof efx); init_packet( &pkt ); if( filenames ) { fname = filenames->d; multifile = !!filenames->next; } else fname = NULL; if( fname && filenames->next && (!detached || encryptflag) ) log_bug("multiple files can only be detached signed"); if(opt.ask_sig_expire && !opt.pgp2 && !opt.batch && !opt.force_v3_sigs && !old_style) duration=ask_expire_interval(1); if( (rc=build_sk_list( locusr, &sk_list, 1, PUBKEY_USAGE_SIG )) ) goto leave; if( (!old_style && !duration) || opt.pgp2 ) old_style = only_old_style( sk_list ); if(!old_style && opt.pgp2) { log_info(_("you can only sign with PGP 2.x style keys " "while in --pgp2 mode\n")); log_info(_("this message may not be usable by PGP 2.x\n")); opt.pgp2=0; } if( encryptflag ) { if( (rc=build_pk_list( remusr, &pk_list, PUBKEY_USAGE_ENC )) ) goto leave; if( !old_style ) compr_algo = select_algo_from_prefs( pk_list, PREFTYPE_ZIP ); } /* prepare iobufs */ if( multifile ) /* have list of filenames */ inp = NULL; /* we do it later */ else if( !(inp = iobuf_open(fname)) ) { log_error("can't open %s: %s\n", fname? fname: "[stdin]", strerror(errno) ); rc = G10ERR_OPEN_FILE; goto leave; } if( outfile ) { if( !(out = iobuf_create( outfile )) ) { log_error(_("can't create %s: %s\n"), outfile, strerror(errno) ); rc = G10ERR_CREATE_FILE; goto leave; } else if( opt.verbose ) log_info(_("writing to `%s'\n"), outfile ); } else if( (rc = open_outfile( fname, opt.armor? 1: detached? 2:0, &out ))) goto leave; /* prepare to calculate the MD over the input */ if( opt.textmode && !outfile ) iobuf_push_filter( inp, text_filter, &tfx ); mfx.md = md_open(0, 0); for( sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next ) { PKT_secret_key *sk = sk_rover->sk; md_enable(mfx.md, hash_for(sk->pubkey_algo, sk->version )); } if( !multifile ) iobuf_push_filter( inp, md_filter, &mfx ); if( detached && !encryptflag && !opt.rfc1991 ) afx.what = 2; if( opt.armor && !outfile ) iobuf_push_filter( out, armor_filter, &afx ); if( encryptflag ) { efx.pk_list = pk_list; /* fixme: set efx.cfx.datalen if known */ iobuf_push_filter( out, encrypt_filter, &efx ); } if( opt.compress && !outfile && ( !detached || opt.compress_sigs) ) { if( !compr_algo ) ; /* don't use compression */ else { if( old_style || compr_algo == 1 || (compr_algo == -1 && !encryptflag) ) zfx.algo = 1; /* use the non optional algorithm */ iobuf_push_filter( out, compress_filter, &zfx ); } } /* Write the one-pass signature packets if needed */ if (!detached && !opt.rfc1991) { rc = write_onepass_sig_packets (sk_list, out, opt.textmode && !outfile ? 0x01:0x00); if (rc) goto leave; } /* setup the inner packet */ if( detached ) { if( multifile ) { STRLIST sl; if( opt.verbose ) log_info(_("signing:") ); /* must walk reverse trough this list */ for( sl = strlist_last(filenames); sl; sl = strlist_prev( filenames, sl ) ) { if( !(inp = iobuf_open(sl->d)) ) { log_error(_("can't open %s: %s\n"), sl->d, strerror(errno) ); rc = G10ERR_OPEN_FILE; goto leave; } if( opt.verbose ) fprintf(stderr, " `%s'", sl->d ); iobuf_push_filter( inp, md_filter, &mfx ); while( iobuf_get(inp) != -1 ) ; iobuf_close(inp); inp = NULL; } if( opt.verbose ) putc( '\n', stderr ); } else { /* read, so that the filter can calculate the digest */ while( iobuf_get(inp) != -1 ) ; } } else { rc = write_plaintext_packet (out, inp, fname, opt.textmode && !outfile ? 't':'b'); } /* catch errors from above */ if (rc) goto leave; /* write the signatures */ rc = write_signature_packets (sk_list, out, mfx.md, opt.textmode && !outfile? 0x01 : 0x00, timestamp, duration, old_style, detached ? 'D':'S'); if( rc ) goto leave; leave: if( rc ) iobuf_cancel(out); else { iobuf_close(out); if (encryptflag) write_status( STATUS_END_ENCRYPTION ); } iobuf_close(inp); md_close( mfx.md ); release_sk_list( sk_list ); release_pk_list( pk_list ); return rc; } /**************** * make a clear signature. note that opt.armor is not needed */ int clearsign_file( const char *fname, STRLIST locusr, const char *outfile ) { armor_filter_context_t afx; MD_HANDLE textmd = NULL; IOBUF inp = NULL, out = NULL; PACKET pkt; int rc = 0; SK_LIST sk_list = NULL; SK_LIST sk_rover = NULL; int old_style = opt.rfc1991; int only_md5 = 0; u32 timestamp=0,duration=0; memset( &afx, 0, sizeof afx); init_packet( &pkt ); if(opt.ask_sig_expire && !opt.pgp2 && !opt.batch && !opt.force_v3_sigs && !old_style) duration=ask_expire_interval(1); if( (rc=build_sk_list( locusr, &sk_list, 1, PUBKEY_USAGE_SIG )) ) goto leave; if( (!old_style && !duration) || opt.pgp2 ) old_style = only_old_style( sk_list ); if(!old_style && opt.pgp2) { log_info(_("you can only clearsign with PGP 2.x style keys " "while in --pgp2 mode\n")); log_info(_("this message may not be usable by PGP 2.x\n")); opt.pgp2=0; } /* prepare iobufs */ if( !(inp = iobuf_open(fname)) ) { log_error("can't open %s: %s\n", fname? fname: "[stdin]", strerror(errno) ); rc = G10ERR_OPEN_FILE; goto leave; } if( outfile ) { if( !(out = iobuf_create( outfile )) ) { log_error(_("can't create %s: %s\n"), outfile, strerror(errno) ); rc = G10ERR_CREATE_FILE; goto leave; } else if( opt.verbose ) log_info(_("writing to `%s'\n"), outfile ); } else if( (rc = open_outfile( fname, 1, &out )) ) goto leave; iobuf_writestr(out, "-----BEGIN PGP SIGNED MESSAGE-----" LF ); for( sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next ) { PKT_secret_key *sk = sk_rover->sk; if( hash_for(sk->pubkey_algo, sk->version) == DIGEST_ALGO_MD5 ) only_md5 = 1; else { only_md5 = 0; break; } } if( !(old_style && only_md5) ) { const char *s; int any = 0; byte hashs_seen[256]; memset( hashs_seen, 0, sizeof hashs_seen ); iobuf_writestr(out, "Hash: " ); for( sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next ) { PKT_secret_key *sk = sk_rover->sk; int i = hash_for(sk->pubkey_algo, sk->version); if( !hashs_seen[ i & 0xff ] ) { s = digest_algo_to_string( i ); if( s ) { hashs_seen[ i & 0xff ] = 1; if( any ) iobuf_put(out, ',' ); iobuf_writestr(out, s ); any = 1; } } } assert(any); iobuf_writestr(out, LF ); } if( opt.not_dash_escaped ) iobuf_writestr( out, "NotDashEscaped: You need GnuPG to verify this message" LF ); iobuf_writestr(out, LF ); textmd = md_open(0, 0); for( sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next ) { PKT_secret_key *sk = sk_rover->sk; md_enable(textmd, hash_for(sk->pubkey_algo, sk->version)); } if ( DBG_HASHING ) md_start_debug( textmd, "clearsign" ); copy_clearsig_text( out, inp, textmd, !opt.not_dash_escaped, opt.escape_from, old_style ); /* fixme: check for read errors */ /* now write the armor */ afx.what = 2; iobuf_push_filter( out, armor_filter, &afx ); /* write the signatures */ rc = write_signature_packets (sk_list, out, textmd, 0x01, timestamp, duration, old_style, 'C'); if( rc ) goto leave; leave: if( rc ) iobuf_cancel(out); else iobuf_close(out); iobuf_close(inp); md_close( textmd ); release_sk_list( sk_list ); return rc; } /* * Sign and conventionally encrypt the given file. * FIXME: Far too much code is duplicated - revamp the whole file. */ int sign_symencrypt_file (const char *fname, STRLIST locusr) { armor_filter_context_t afx; compress_filter_context_t zfx; md_filter_context_t mfx; text_filter_context_t tfx; cipher_filter_context_t cfx; IOBUF inp = NULL, out = NULL; PACKET pkt; STRING2KEY *s2k = NULL; int rc = 0; SK_LIST sk_list = NULL; SK_LIST sk_rover = NULL; int old_style = opt.rfc1991; int compr_algo = -1; /* unknown */ int algo; u32 timestamp=0,duration=0; memset( &afx, 0, sizeof afx); memset( &zfx, 0, sizeof zfx); memset( &mfx, 0, sizeof mfx); memset( &tfx, 0, sizeof tfx); memset( &cfx, 0, sizeof cfx); init_packet( &pkt ); if(opt.ask_sig_expire && !opt.batch && !opt.force_v3_sigs && !old_style) duration=ask_expire_interval(1); rc = build_sk_list (locusr, &sk_list, 1, PUBKEY_USAGE_SIG); if (rc) goto leave; if( !old_style && !duration ) old_style = only_old_style( sk_list ); /* prepare iobufs */ inp = iobuf_open(fname); if( !inp ) { log_error("can't open %s: %s\n", fname? fname: "[stdin]", strerror(errno) ); rc = G10ERR_OPEN_FILE; goto leave; } /* prepare key */ s2k = m_alloc_clear( sizeof *s2k ); s2k->mode = opt.rfc1991? 0:opt.s2k_mode; s2k->hash_algo = opt.def_digest_algo ? opt.def_digest_algo : opt.s2k_digest_algo; algo = opt.def_cipher_algo ? opt.def_cipher_algo : opt.s2k_cipher_algo; if (!opt.quiet || !opt.batch) log_info (_("%s encryption will be used\n"), cipher_algo_to_string(algo) ); cfx.dek = passphrase_to_dek( NULL, 0, algo, s2k, 2, NULL ); if (!cfx.dek || !cfx.dek->keylen) { rc = G10ERR_PASSPHRASE; log_error(_("error creating passphrase: %s\n"), g10_errstr(rc) ); goto leave; } /* now create the outfile */ rc = open_outfile (fname, opt.armor? 1:0, &out); if (rc) goto leave; /* prepare to calculate the MD over the input */ if (opt.textmode) iobuf_push_filter (inp, text_filter, &tfx); mfx.md = md_open(0, 0); for (sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next) { PKT_secret_key *sk = sk_rover->sk; md_enable (mfx.md, hash_for (sk->pubkey_algo, sk->version )); } iobuf_push_filter (inp, md_filter, &mfx); /* Push armor output filter */ if (opt.armor) iobuf_push_filter (out, armor_filter, &afx); /* Write the symmetric key packet */ /*(current filters: armor)*/ if (!opt.rfc1991) { PKT_symkey_enc *enc = m_alloc_clear( sizeof *enc ); enc->version = 4; enc->cipher_algo = cfx.dek->algo; enc->s2k = *s2k; pkt.pkttype = PKT_SYMKEY_ENC; pkt.pkt.symkey_enc = enc; if( (rc = build_packet( out, &pkt )) ) log_error("build symkey packet failed: %s\n", g10_errstr(rc) ); m_free(enc); } /* Push the encryption filter */ iobuf_push_filter( out, cipher_filter, &cfx ); /* Push the Zip filter */ if (opt.compress) { if (!compr_algo) ; /* don't use compression */ else { if( old_style || compr_algo == 1 ) zfx.algo = 1; /* use the non optional algorithm */ iobuf_push_filter( out, compress_filter, &zfx ); } } /* Write the one-pass signature packets */ /*(current filters: zip - encrypt - armor)*/ if (!opt.rfc1991) { rc = write_onepass_sig_packets (sk_list, out, opt.textmode? 0x01:0x00); if (rc) goto leave; } /* Pipe data through all filters; i.e. write the signed stuff */ /*(current filters: zip - encrypt - armor)*/ rc = write_plaintext_packet (out, inp, fname, opt.textmode ? 't':'b'); if (rc) goto leave; /* Write the signatures */ /*(current filters: zip - encrypt - armor)*/ rc = write_signature_packets (sk_list, out, mfx.md, opt.textmode? 0x01 : 0x00, timestamp, duration, old_style, 'S'); if( rc ) goto leave; leave: if( rc ) iobuf_cancel(out); else { iobuf_close(out); write_status( STATUS_END_ENCRYPTION ); } iobuf_close(inp); release_sk_list( sk_list ); md_close( mfx.md ); m_free(cfx.dek); m_free(s2k); return rc; } /**************** * Create a signature packet for the given public key certificate and * the user id and return it in ret_sig. User signature class SIGCLASS * user-id is not used (and may be NULL if sigclass is 0x20) If * DIGEST_ALGO is 0 the function selects an appropriate one. * SIGVERSION gives the minimal required signature packet version; * this is needed so that special properties like local sign are not * applied (actually: dropped) when a v3 key is used. TIMESTAMP is * the timestamp to use for the signature. 0 means "now" */ int make_keysig_packet( PKT_signature **ret_sig, PKT_public_key *pk, PKT_user_id *uid, PKT_public_key *subpk, PKT_secret_key *sk, int sigclass, int digest_algo, int sigversion, u32 timestamp, u32 duration, int (*mksubpkt)(PKT_signature *, void *), void *opaque ) { PKT_signature *sig; int rc=0; MD_HANDLE md; assert( (sigclass >= 0x10 && sigclass <= 0x13) || sigclass == 0x20 || sigclass == 0x18 || sigclass == 0x30 || sigclass == 0x28 ); if (opt.force_v4_certs) sigversion = 4; if (sigversion < sk->version) sigversion = sk->version; /* If you are making a signature on a v4 key using your v3 key, it doesn't make sense to generate a v3 sig. After all, no v3-only PGP implementation could understand the v4 key in the first place. */ if (sigversion < pk->version) sigversion = pk->version; if( !digest_algo ) { switch( sk->pubkey_algo ) { case PUBKEY_ALGO_DSA: digest_algo = DIGEST_ALGO_SHA1; break; case PUBKEY_ALGO_RSA_S: case PUBKEY_ALGO_RSA: if (opt.force_v4_certs || sk->version > 3) digest_algo = DIGEST_ALGO_SHA1; else digest_algo = DIGEST_ALGO_MD5; break; default: digest_algo = DIGEST_ALGO_RMD160; break; } } md = md_open( digest_algo, 0 ); /* hash the public key certificate and the user id */ hash_public_key( md, pk ); if( sigclass == 0x18 || sigclass == 0x28 ) { /* subkey binding/revocation*/ hash_public_key( md, subpk ); } else if( sigclass != 0x20 ) { hash_uid (md, sigversion, uid); } /* and make the signature packet */ sig = m_alloc_clear( sizeof *sig ); sig->version = sigversion; sig->flags.exportable=1; sig->flags.revocable=1; keyid_from_sk( sk, sig->keyid ); sig->pubkey_algo = sk->pubkey_algo; sig->digest_algo = digest_algo; if(timestamp) sig->timestamp=timestamp; else sig->timestamp=make_timestamp(); if(duration) sig->expiredate=sig->timestamp+duration; sig->sig_class = sigclass; if( sig->version >= 4 ) build_sig_subpkt_from_sig( sig ); if( sig->version >= 4 && mksubpkt ) rc = (*mksubpkt)( sig, opaque ); if( !rc ) { mk_notation_and_policy( sig, pk ); hash_sigversion_to_magic (md, sig); md_final(md); rc = complete_sig( sig, sk, md ); } md_close( md ); if( rc ) free_seckey_enc( sig ); else *ret_sig = sig; return rc; } /**************** * Create a new signature packet based on an existing one. * Only user ID signatures are supported for now. * TODO: Merge this with make_keysig_packet. */ int update_keysig_packet( PKT_signature **ret_sig, PKT_signature *orig_sig, PKT_public_key *pk, PKT_user_id *uid, PKT_secret_key *sk, int (*mksubpkt)(PKT_signature *, void *), void *opaque ) { PKT_signature *sig; int rc=0; MD_HANDLE md; if (!orig_sig || !pk || !uid || !sk) return G10ERR_GENERAL; if (orig_sig->sig_class < 0x10 || orig_sig->sig_class > 0x13 ) return G10ERR_GENERAL; md = md_open( orig_sig->digest_algo, 0 ); /* hash the public key certificate and the user id */ hash_public_key( md, pk ); hash_uid (md, orig_sig->version, uid); /* create a new signature packet */ sig = copy_signature (NULL, orig_sig); if ( sig->version >= 4 && mksubpkt) rc = (*mksubpkt)(sig, opaque); /* we increase the timestamp by one second so that a future import of this key will replace the existing one. We also make sure that we don't create a timestamp in the future */ sig->timestamp++; while (sig->timestamp >= make_timestamp()) sleep (1); /* put the updated timestamp back into the data */ if( sig->version >= 4 ) build_sig_subpkt_from_sig( sig ); if (!rc) { hash_sigversion_to_magic (md, sig); md_final(md); rc = complete_sig( sig, sk, md ); } md_close (md); if( rc ) free_seckey_enc (sig); else *ret_sig = sig; return rc; }