diff options
Diffstat (limited to '')
| -rw-r--r-- | g10/mainproc.c | 52 |
1 files changed, 43 insertions, 9 deletions
diff --git a/g10/mainproc.c b/g10/mainproc.c index d0d76ab9a..4dec7487b 100644 --- a/g10/mainproc.c +++ b/g10/mainproc.c @@ -1,6 +1,7 @@ /* mainproc.c - handle packets * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, * 2008, 2009 Free Software Foundation, Inc. + * Copyright (C) 2013 Werner Koch * * This file is part of GnuPG. * @@ -42,6 +43,11 @@ #include "pka.h" +/* Put an upper limit on nested packets. The 32 is an arbitrary + value, a much lower should actually be sufficient. */ +#define MAX_NESTING_DEPTH 32 + + struct kidlist_item { struct kidlist_item *next; u32 kid[2]; @@ -768,7 +774,7 @@ proc_encrypt_cb (IOBUF a, void *info ) return proc_encryption_packets (c->ctrl, info, a ); } -static void +static int proc_compressed( CTX c, PACKET *pkt ) { PKT_compressed *zd = pkt->pkt.compressed; @@ -785,6 +791,7 @@ proc_compressed( CTX c, PACKET *pkt ) log_error("uncompressing failed: %s\n", g10_errstr(rc)); free_packet(pkt); c->last_was_session_key = 0; + return rc; } /**************** @@ -1282,14 +1289,37 @@ proc_encryption_packets (ctrl_t ctrl, void *anchor, IOBUF a ) } -int +static int +check_nesting (CTX c) +{ + int level; + + for (level = 0; c; c = c->anchor) + level++; + + if (level > MAX_NESTING_DEPTH) + { + log_error ("input data with too deeply nested packets\n"); + write_status_text (STATUS_UNEXPECTED, "1"); + return G10ERR_UNEXPECTED; + } + return 0; +} + + +static int do_proc_packets( CTX c, IOBUF a ) { - PACKET *pkt = xmalloc( sizeof *pkt ); - int rc=0; - int any_data=0; + PACKET *pkt; + int rc = 0; + int any_data = 0; int newpkt; + rc = check_nesting (c); + if (rc) + return rc; + + pkt = xmalloc( sizeof *pkt ); c->iobuf = a; init_packet(pkt); while( (rc=parse_packet(a, pkt)) != -1 ) { @@ -1310,7 +1340,7 @@ do_proc_packets( CTX c, IOBUF a ) case PKT_SYMKEY_ENC: proc_symkey_enc( c, pkt ); break; case PKT_ENCRYPTED: case PKT_ENCRYPTED_MDC: proc_encrypted( c, pkt ); break; - case PKT_COMPRESSED: proc_compressed( c, pkt ); break; + case PKT_COMPRESSED: rc = proc_compressed( c, pkt ); break; default: newpkt = 0; break; } } @@ -1328,7 +1358,7 @@ do_proc_packets( CTX c, IOBUF a ) goto leave; case PKT_SIGNATURE: newpkt = add_signature( c, pkt ); break; case PKT_PLAINTEXT: proc_plaintext( c, pkt ); break; - case PKT_COMPRESSED: proc_compressed( c, pkt ); break; + case PKT_COMPRESSED: rc = proc_compressed( c, pkt ); break; case PKT_ONEPASS_SIG: newpkt = add_onepass_sig( c, pkt ); break; case PKT_GPG_CONTROL: newpkt = add_gpg_control(c, pkt); break; default: newpkt = 0; break; @@ -1348,7 +1378,7 @@ do_proc_packets( CTX c, IOBUF a ) case PKT_ENCRYPTED: case PKT_ENCRYPTED_MDC: proc_encrypted( c, pkt ); break; case PKT_PLAINTEXT: proc_plaintext( c, pkt ); break; - case PKT_COMPRESSED: proc_compressed( c, pkt ); break; + case PKT_COMPRESSED: rc = proc_compressed( c, pkt ); break; case PKT_ONEPASS_SIG: newpkt = add_onepass_sig( c, pkt ); break; case PKT_GPG_CONTROL: newpkt = add_gpg_control(c, pkt); break; default: newpkt = 0; break; @@ -1373,13 +1403,17 @@ do_proc_packets( CTX c, IOBUF a ) case PKT_ENCRYPTED: case PKT_ENCRYPTED_MDC: proc_encrypted( c, pkt ); break; case PKT_PLAINTEXT: proc_plaintext( c, pkt ); break; - case PKT_COMPRESSED: proc_compressed( c, pkt ); break; + case PKT_COMPRESSED: rc = proc_compressed( c, pkt ); break; case PKT_ONEPASS_SIG: newpkt = add_onepass_sig( c, pkt ); break; case PKT_GPG_CONTROL: newpkt = add_gpg_control(c, pkt); break; case PKT_RING_TRUST: newpkt = add_ring_trust( c, pkt ); break; default: newpkt = 0; break; } } + + if (rc) + goto leave; + /* This is a very ugly construct and frankly, I don't remember why * I used it. Adding the MDC check here is a hack. * The right solution is to initiate another context for encrypted |