diff options
Diffstat (limited to 'g10/parse-packet.c')
| -rw-r--r-- | g10/parse-packet.c | 147 |
1 files changed, 132 insertions, 15 deletions
diff --git a/g10/parse-packet.c b/g10/parse-packet.c index a64d4f723..e933abfa0 100644 --- a/g10/parse-packet.c +++ b/g10/parse-packet.c @@ -1,7 +1,6 @@ /* parse-packet.c - read packets - * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, - * 2007, 2009, 2010 Free Software Foundation, Inc. - * Copyright (C) 2014 Werner Koch + * Copyright (C) 1998-2007, 2009-2010 Free Software Foundation, Inc. + * Copyright (C) 2014, 2018 Werner Koch * Copyright (C) 2015 g10 Code GmbH * * This file is part of GnuPG. @@ -18,6 +17,7 @@ * * You should have received a copy of the GNU General Public License * along with this program; if not, see <https://www.gnu.org/licenses/>. + * SPDX-License-Identifier: GPL-3.0+ */ #include <config.h> @@ -82,6 +82,9 @@ static int parse_compressed (IOBUF inp, int pkttype, unsigned long pktlen, PACKET * packet, int new_ctb); static int parse_encrypted (IOBUF inp, int pkttype, unsigned long pktlen, PACKET * packet, int new_ctb, int partial); +static gpg_error_t parse_encrypted_aead (IOBUF inp, int pkttype, + unsigned long pktlen, PACKET *packet, + int partial); static int parse_mdc (IOBUF inp, int pkttype, unsigned long pktlen, PACKET * packet, int new_ctb); static int parse_gpg_control (IOBUF inp, int pkttype, unsigned long pktlen, @@ -636,6 +639,7 @@ parse (parse_packet_ctx_t ctx, PACKET *pkt, int onlykeypkts, off_t * retpos, case PKT_PLAINTEXT: case PKT_ENCRYPTED: case PKT_ENCRYPTED_MDC: + case PKT_ENCRYPTED_AEAD: case PKT_COMPRESSED: iobuf_set_partial_body_length_mode (inp, c & 0xff); pktlen = 0; /* To indicate partial length. */ @@ -823,6 +827,9 @@ parse (parse_packet_ctx_t ctx, PACKET *pkt, int onlykeypkts, off_t * retpos, case PKT_MDC: rc = parse_mdc (inp, pkttype, pktlen, pkt, new_ctb); break; + case PKT_ENCRYPTED_AEAD: + rc = parse_encrypted_aead (inp, pkttype, pktlen, pkt, partial); + break; case PKT_GPG_CONTROL: rc = parse_gpg_control (inp, pkttype, pktlen, pkt, partial); break; @@ -1098,19 +1105,17 @@ parse_symkeyenc (IOBUF inp, int pkttype, unsigned long pktlen, { PKT_symkey_enc *k; int rc = 0; - int i, version, s2kmode, cipher_algo, hash_algo, seskeylen, minlen; + int i, version, s2kmode, cipher_algo, aead_algo, hash_algo, seskeylen, minlen; if (pktlen < 4) - { - log_error ("packet(%d) too short\n", pkttype); - if (list_mode) - es_fprintf (listfp, ":symkey enc packet: [too short]\n"); - rc = gpg_error (GPG_ERR_INV_PACKET); - goto leave; - } + goto too_short; version = iobuf_get_noeof (inp); pktlen--; - if (version != 4) + if (version == 4) + ; + else if (version == 5) + ; + else { log_error ("packet(%d) with unknown version %d\n", pkttype, version); if (list_mode) @@ -1128,6 +1133,15 @@ parse_symkeyenc (IOBUF inp, int pkttype, unsigned long pktlen, } cipher_algo = iobuf_get_noeof (inp); pktlen--; + if (version == 5) + { + aead_algo = iobuf_get_noeof (inp); + pktlen--; + } + else + aead_algo = 0; + if (pktlen < 2) + goto too_short; s2kmode = iobuf_get_noeof (inp); pktlen--; hash_algo = iobuf_get_noeof (inp); @@ -1162,6 +1176,7 @@ parse_symkeyenc (IOBUF inp, int pkttype, unsigned long pktlen, + seskeylen - 1); k->version = version; k->cipher_algo = cipher_algo; + k->aead_algo = aead_algo; k->s2k.mode = s2kmode; k->s2k.hash_algo = hash_algo; if (s2kmode == 1 || s2kmode == 3) @@ -1192,10 +1207,20 @@ parse_symkeyenc (IOBUF inp, int pkttype, unsigned long pktlen, if (list_mode) { es_fprintf (listfp, - ":symkey enc packet: version %d, cipher %d, s2k %d, hash %d", - version, cipher_algo, s2kmode, hash_algo); + ":symkey enc packet: version %d, cipher %d, aead %d," + " s2k %d, hash %d", + version, cipher_algo, aead_algo, s2kmode, hash_algo); if (seskeylen) - es_fprintf (listfp, ", seskey %d bits", (seskeylen - 1) * 8); + { + /* To compute the size of the session key we need to know + * the size of the AEAD nonce which we may not know. Thus + * we show only the seize of the entire encrypted session + * key. */ + if (aead_algo) + es_fprintf (listfp, ", encrypted seskey %d bytes", seskeylen); + else + es_fprintf (listfp, ", seskey %d bits", (seskeylen - 1) * 8); + } es_fprintf (listfp, "\n"); if (s2kmode == 1 || s2kmode == 3) { @@ -1212,6 +1237,13 @@ parse_symkeyenc (IOBUF inp, int pkttype, unsigned long pktlen, leave: iobuf_skip_rest (inp, pktlen, 0); return rc; + + too_short: + log_error ("packet(%d) too short\n", pkttype); + if (list_mode) + es_fprintf (listfp, ":symkey enc packet: [too short]\n"); + rc = gpg_error (GPG_ERR_INV_PACKET); + goto leave; } @@ -1392,6 +1424,11 @@ dump_sig_subpkt (int hashed, int type, int critical, for (i = 0; i < length; i++) es_fprintf (listfp, " %d", buffer[i]); break; + case SIGSUBPKT_PREF_AEAD: + es_fputs ("pref-aead-algos:", listfp); + for (i = 0; i < length; i++) + es_fprintf (listfp, " %d", buffer[i]); + break; case SIGSUBPKT_REV_KEY: es_fputs ("revocation key: ", listfp); if (length < 22) @@ -1554,6 +1591,7 @@ parse_one_sig_subpkt (const byte * buffer, size_t n, int type) case SIGSUBPKT_KEY_FLAGS: case SIGSUBPKT_KS_FLAGS: case SIGSUBPKT_PREF_SYM: + case SIGSUBPKT_PREF_AEAD: case SIGSUBPKT_PREF_HASH: case SIGSUBPKT_PREF_COMPR: case SIGSUBPKT_POLICY: @@ -1636,6 +1674,7 @@ can_handle_critical (const byte * buffer, size_t n, int type) case SIGSUBPKT_ISSUER: /* issuer key ID */ case SIGSUBPKT_ISSUER_FPR: /* issuer fingerprint */ case SIGSUBPKT_PREF_SYM: + case SIGSUBPKT_PREF_AEAD: case SIGSUBPKT_PREF_HASH: case SIGSUBPKT_PREF_COMPR: case SIGSUBPKT_KEY_FLAGS: @@ -3170,6 +3209,9 @@ parse_encrypted (IOBUF inp, int pkttype, unsigned long pktlen, ed->buf = NULL; ed->new_ctb = new_ctb; ed->is_partial = partial; + ed->aead_algo = 0; + ed->cipher_algo = 0; /* Only used with AEAD. */ + ed->chunkbyte = 0; /* Only used with AEAD. */ if (pkttype == PKT_ENCRYPTED_MDC) { /* Fixme: add some pktlen sanity checks. */ @@ -3261,6 +3303,81 @@ parse_mdc (IOBUF inp, int pkttype, unsigned long pktlen, } +static gpg_error_t +parse_encrypted_aead (iobuf_t inp, int pkttype, unsigned long pktlen, + PACKET *pkt, int partial) +{ + int rc = 0; + PKT_encrypted *ed; + unsigned long orig_pktlen = pktlen; + int version; + + ed = pkt->pkt.encrypted = xtrymalloc (sizeof *pkt->pkt.encrypted); + if (!ed) + return gpg_error_from_syserror (); + ed->len = 0; + ed->extralen = 0; /* (only used in build_packet.) */ + ed->buf = NULL; + ed->new_ctb = 1; /* (packet number requires a new CTB anyway.) */ + ed->is_partial = partial; + ed->mdc_method = 0; + /* A basic sanity check. We need one version byte, one algo byte, + * one aead algo byte, one chunkbyte, at least 15 byte IV. */ + if (orig_pktlen && pktlen < 19) + { + log_error ("packet(%d) too short\n", pkttype); + if (list_mode) + es_fputs (":aead encrypted packet: [too short]\n", listfp); + rc = gpg_error (GPG_ERR_INV_PACKET); + iobuf_skip_rest (inp, pktlen, partial); + goto leave; + } + + version = iobuf_get_noeof (inp); + if (orig_pktlen) + pktlen--; + if (version != 1) + { + log_error ("aead encrypted packet with unknown version %d\n", + version); + if (list_mode) + es_fputs (":aead encrypted packet: [unknown version]\n", listfp); + /*skip_rest(inp, pktlen); should we really do this? */ + rc = gpg_error (GPG_ERR_INV_PACKET); + goto leave; + } + + ed->cipher_algo = iobuf_get_noeof (inp); + if (orig_pktlen) + pktlen--; + ed->aead_algo = iobuf_get_noeof (inp); + if (orig_pktlen) + pktlen--; + ed->chunkbyte = iobuf_get_noeof (inp); + if (orig_pktlen) + pktlen--; + + /* Store the remaining length of the encrypted data. We read the + * rest during decryption. */ + ed->len = pktlen; + + if (list_mode) + { + es_fprintf (listfp, ":aead encrypted packet: cipher=%u aead=%u cb=%u\n", + ed->cipher_algo, ed->aead_algo, ed->chunkbyte); + if (orig_pktlen) + es_fprintf (listfp, "\tlength: %lu\n", orig_pktlen); + else + es_fprintf (listfp, "\tlength: unknown\n"); + } + + ed->buf = inp; + + leave: + return rc; +} + + /* * This packet is internally generated by us (in armor.c) to transfer * some information to the lower layer. To make sure that this packet |