Major new upstream release, just ran svn-upgrade for now (and wrote some

debian/changelong entries).

1 files changed, 1244 insertions, 0 deletions

diff --git a/src/pluto/packet.c b/src/pluto/packet.c
new file mode 100644
index 000000000..9f04c8bb2
--- /dev/null
+++ b/src/pluto/packet.c
@@ -0,0 +1,1244 @@
+/* parsing packets: formats and tools
+ * Copyright (C) 1997 Angelos D. Keromytis.
+ * Copyright (C) 1998-2001  D. Hugh Redelmeier.
+ *
+ * This program 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program 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.
+ *
+ * RCSID $Id: packet.c,v 1.7 2005/01/06 22:39:04 as Exp $
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <netinet/in.h>
+#include <string.h>
+
+#include <freeswan.h>
+
+#include "constants.h"
+#include "defs.h"
+#include "log.h"
+#include "packet.h"
+#include "whack.h"	/* for RC_LOG_SERIOUS */
+
+/* ISAKMP Header: for all messages
+ * layout from RFC 2408 "ISAKMP" section 3.1
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                          Initiator                            !
+ * !                            Cookie                             !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                          Responder                            !
+ * !                            Cookie                             !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !  Next Payload ! MjVer ! MnVer ! Exchange Type !     Flags     !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                          Message ID                           !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                            Length                             !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+
+static field_desc isa_fields[] = {
+    { ft_raw, COOKIE_SIZE, "initiator cookie", NULL },
+    { ft_raw, COOKIE_SIZE, "responder cookie", NULL },
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_enum, 8/BITS_PER_BYTE, "ISAKMP version", &version_names },
+    { ft_enum, 8/BITS_PER_BYTE, "exchange type", &exchange_names },
+    { ft_set, 8/BITS_PER_BYTE, "flags", flag_bit_names },
+    { ft_raw, 32/BITS_PER_BYTE, "message ID", NULL },
+    { ft_len, 32/BITS_PER_BYTE, "length", NULL },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_hdr_desc = { "ISAKMP Message", isa_fields, sizeof(struct isakmp_hdr) };
+
+/* Generic portion of all ISAKMP payloads.
+ * layout from RFC 2408 "ISAKMP" section 3.2
+ * This describes the first 32-bit chunk of all payloads.
+ * The previous next payload depends on the actual payload type.
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+
+static field_desc isag_fields[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_generic_desc = { "ISAKMP Generic Payload", isag_fields, sizeof(struct isakmp_generic) };
+
+
+/* ISAKMP Data Attribute (generic representation within payloads)
+ * layout from RFC 2408 "ISAKMP" section 3.3
+ * This is not a payload type.
+ * In TLV format, this is followed by a value field.
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !A!       Attribute Type        !    AF=0  Attribute Length     !
+ * !F!                             !    AF=1  Attribute Value      !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * .                   AF=0  Attribute Value                       .
+ * .                   AF=1  Not Transmitted                       .
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+
+/* Oakley Attributes */
+static field_desc isaat_fields_oakley[] = {
+    { ft_af_enum, 16/BITS_PER_BYTE, "af+type", &oakley_attr_names },
+    { ft_lv, 16/BITS_PER_BYTE, "length/value", NULL },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_oakley_attribute_desc = {
+    "ISAKMP Oakley attribute",
+    isaat_fields_oakley, sizeof(struct isakmp_attribute) };
+
+/* IPsec DOI Attributes */
+static field_desc isaat_fields_ipsec[] = {
+    { ft_af_enum, 16/BITS_PER_BYTE, "af+type", &ipsec_attr_names },
+    { ft_lv, 16/BITS_PER_BYTE, "length/value", NULL },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_ipsec_attribute_desc = {
+    "ISAKMP IPsec DOI attribute",
+    isaat_fields_ipsec, sizeof(struct isakmp_attribute) };
+
+/* Mode Config Attributes */
+static field_desc isaat_fields_modecfg[] = {
+    { ft_af_loose_enum, 16/BITS_PER_BYTE, "ModeCfg attr type", &modecfg_attr_names },
+    { ft_lv, 16/BITS_PER_BYTE, "length/value", NULL },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_modecfg_attribute_desc = {
+    "ISAKMP ModeCfg attribute",
+    isaat_fields_modecfg, sizeof(struct isakmp_attribute) };
+
+/* ISAKMP Security Association Payload
+ * layout from RFC 2408 "ISAKMP" section 3.4
+ * A variable length Situation follows.
+ * Previous next payload: ISAKMP_NEXT_SA
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !              Domain of Interpretation  (DOI)                  !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                                                               !
+ * ~                           Situation                           ~
+ * !                                                               !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+static field_desc isasa_fields[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_enum, 32/BITS_PER_BYTE, "DOI", &doi_names },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_sa_desc = { "ISAKMP Security Association Payload", isasa_fields, sizeof(struct isakmp_sa) };
+
+static field_desc ipsec_sit_field[] = {
+    { ft_set, 32/BITS_PER_BYTE, "IPsec DOI SIT", &sit_bit_names },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc ipsec_sit_desc = { "IPsec DOI SIT", ipsec_sit_field, sizeof(u_int32_t) };
+
+/* ISAKMP Proposal Payload
+ * layout from RFC 2408 "ISAKMP" section 3.5
+ * A variable length SPI follows.
+ * Previous next payload: ISAKMP_NEXT_P
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !  Proposal #   !  Protocol-Id  !    SPI Size   !# of Transforms!
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                        SPI (variable)                         !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+static field_desc isap_fields[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_nat, 8/BITS_PER_BYTE, "proposal number", NULL },
+    { ft_enum, 8/BITS_PER_BYTE, "protocol ID", &protocol_names },
+    { ft_nat, 8/BITS_PER_BYTE, "SPI size", NULL },
+    { ft_nat, 8/BITS_PER_BYTE, "number of transforms", NULL },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_proposal_desc = { "ISAKMP Proposal Payload", isap_fields, sizeof(struct isakmp_proposal) };
+
+/* ISAKMP Transform Payload
+ * layout from RFC 2408 "ISAKMP" section 3.6
+ * Variable length SA Attributes follow.
+ * Previous next payload: ISAKMP_NEXT_T
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !  Transform #  !  Transform-Id !           RESERVED2           !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                                                               !
+ * ~                        SA Attributes                          ~
+ * !                                                               !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+
+/* PROTO_ISAKMP */
+static field_desc isat_fields_isakmp[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_nat, 8/BITS_PER_BYTE, "transform number", NULL },
+    { ft_enum, 8/BITS_PER_BYTE, "transform ID", &isakmp_transformid_names },
+    { ft_mbz, 16/BITS_PER_BYTE, NULL, NULL },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_isakmp_transform_desc = {
+    "ISAKMP Transform Payload (ISAKMP)",
+    isat_fields_isakmp, sizeof(struct isakmp_transform) };
+
+/* PROTO_IPSEC_AH */
+static field_desc isat_fields_ah[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_nat, 8/BITS_PER_BYTE, "transform number", NULL },
+    { ft_enum, 8/BITS_PER_BYTE, "transform ID", &ah_transformid_names },
+    { ft_mbz, 16/BITS_PER_BYTE, NULL, NULL },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_ah_transform_desc = {
+    "ISAKMP Transform Payload (AH)",
+    isat_fields_ah, sizeof(struct isakmp_transform) };
+
+/* PROTO_IPSEC_ESP */
+static field_desc isat_fields_esp[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_nat, 8/BITS_PER_BYTE, "transform number", NULL },
+    { ft_enum, 8/BITS_PER_BYTE, "transform ID", &esp_transformid_names },
+    { ft_mbz, 16/BITS_PER_BYTE, NULL, NULL },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_esp_transform_desc = {
+    "ISAKMP Transform Payload (ESP)",
+    isat_fields_esp, sizeof(struct isakmp_transform) };
+
+/* PROTO_IPCOMP */
+static field_desc isat_fields_ipcomp[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_nat, 8/BITS_PER_BYTE, "transform number", NULL },
+    { ft_enum, 8/BITS_PER_BYTE, "transform ID", &ipcomp_transformid_names },
+    { ft_mbz, 16/BITS_PER_BYTE, NULL, NULL },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_ipcomp_transform_desc = {
+    "ISAKMP Transform Payload (COMP)",
+    isat_fields_ipcomp, sizeof(struct isakmp_transform) };
+
+
+/* ISAKMP Key Exchange Payload: no fixed fields beyond the generic ones.
+ * layout from RFC 2408 "ISAKMP" section 3.7
+ * Variable Key Exchange Data follow the generic fields.
+ * Previous next payload: ISAKMP_NEXT_KE
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                                                               !
+ * ~                       Key Exchange Data                       ~
+ * !                                                               !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+struct_desc isakmp_keyex_desc = { "ISAKMP Key Exchange Payload", isag_fields, sizeof(struct isakmp_generic) };
+
+/* ISAKMP Identification Payload
+ * layout from RFC 2408 "ISAKMP" section 3.8
+ * See "struct identity" declared later.
+ * Variable length Identification Data follow.
+ * Previous next payload: ISAKMP_NEXT_ID
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !   ID Type     !             DOI Specific ID Data              !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                                                               !
+ * ~                   Identification Data                         ~
+ * !                                                               !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+static field_desc isaid_fields[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_enum, 8/BITS_PER_BYTE, "ID type", &ident_names },	/* ??? depends on DOI? */
+    { ft_nat, 8/BITS_PER_BYTE, "DOI specific A", NULL },	/* ??? depends on DOI? */
+    { ft_nat, 16/BITS_PER_BYTE, "DOI specific B", NULL },	/* ??? depends on DOI? */
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_identification_desc = { "ISAKMP Identification Payload", isaid_fields, sizeof(struct isakmp_id) };
+
+/* IPSEC Identification Payload Content
+ * layout from RFC 2407 "IPsec DOI" section 4.6.2
+ * See struct isakmp_id declared earlier.
+ * Note: Hashing skips the ISAKMP generic payload header
+ * Variable length Identification Data follow.
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !  Next Payload !   RESERVED    !        Payload Length         !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !   ID Type     !  Protocol ID  !             Port              !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ~                     Identification Data                       ~
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+static field_desc isaiid_fields[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_enum, 8/BITS_PER_BYTE, "ID type", &ident_names },
+    { ft_nat, 8/BITS_PER_BYTE, "Protocol ID", NULL },	/* ??? UDP/TCP or 0? */
+    { ft_nat, 16/BITS_PER_BYTE, "port", NULL },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_ipsec_identification_desc = { "ISAKMP Identification Payload (IPsec DOI)", isaiid_fields, sizeof(struct isakmp_ipsec_id) };
+
+/* ISAKMP Certificate Payload: oddball fixed field beyond the generic ones.
+ * layout from RFC 2408 "ISAKMP" section 3.9
+ * Variable length Certificate Data follow the generic fields.
+ * Previous next payload: ISAKMP_NEXT_CERT.
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Cert Encoding !                                               !
+ * +-+-+-+-+-+-+-+-+                                               !
+ * ~                       Certificate Data                        ~
+ * !                                                               !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+static field_desc isacert_fields[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_enum, 8/BITS_PER_BYTE, "cert encoding", &cert_type_names },
+    { ft_end, 0, NULL, NULL }
+};
+
+/* Note: the size field of isakmp_ipsec_certificate_desc cannot be
+ * sizeof(struct isakmp_cert) because that will rounded up for padding.
+ */
+ struct_desc isakmp_ipsec_certificate_desc = { "ISAKMP Certificate Payload", isacert_fields, ISAKMP_CERT_SIZE };
+
+/* ISAKMP Certificate Request Payload: oddball field beyond the generic ones.
+ * layout from RFC 2408 "ISAKMP" section 3.10
+ * Variable length Certificate Types and Certificate Authorities follow.
+ * Previous next payload: ISAKMP_NEXT_CR.
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !  Cert. Type   !                                               !
+ * +-+-+-+-+-+-+-+-+                                               !
+ * ~                    Certificate Authority                      ~
+ * !                                                               !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+static field_desc isacr_fields[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_enum, 8/BITS_PER_BYTE, "cert type", &cert_type_names },
+    { ft_end, 0, NULL, NULL }
+};
+
+/* Note: the size field of isakmp_ipsec_cert_req_desc cannot be
+ * sizeof(struct isakmp_cr) because that will rounded up for padding.
+ */
+struct_desc isakmp_ipsec_cert_req_desc = { "ISAKMP Certificate RequestPayload", isacr_fields, ISAKMP_CR_SIZE };
+
+/* ISAKMP Hash Payload: no fixed fields beyond the generic ones.
+ * layout from RFC 2408 "ISAKMP" section 3.11
+ * Variable length Hash Data follow.
+ * Previous next payload: ISAKMP_NEXT_HASH.
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                                                               !
+ * ~                           Hash Data                           ~
+ * !                                                               !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+struct_desc isakmp_hash_desc = { "ISAKMP Hash Payload", isag_fields, sizeof(struct isakmp_generic) };
+
+/* ISAKMP Signature Payload: no fixed fields beyond the generic ones.
+ * layout from RFC 2408 "ISAKMP" section 3.12
+ * Variable length Signature Data follow.
+ * Previous next payload: ISAKMP_NEXT_SIG.
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                                                               !
+ * ~                         Signature Data                        ~
+ * !                                                               !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+struct_desc isakmp_signature_desc = { "ISAKMP Signature Payload", isag_fields, sizeof(struct isakmp_generic) };
+
+/* ISAKMP Nonce Payload: no fixed fields beyond the generic ones.
+ * layout from RFC 2408 "ISAKMP" section 3.13
+ * Variable length Nonce Data follow.
+ * Previous next payload: ISAKMP_NEXT_NONCE.
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                                                               !
+ * ~                            Nonce Data                         ~
+ * !                                                               !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+struct_desc isakmp_nonce_desc = { "ISAKMP Nonce Payload", isag_fields, sizeof(struct isakmp_generic) };
+
+/* ISAKMP Notification Payload
+ * layout from RFC 2408 "ISAKMP" section 3.14
+ * This is followed by a variable length SPI
+ * and then possibly by variable length Notification Data.
+ * Previous next payload: ISAKMP_NEXT_N
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !              Domain of Interpretation  (DOI)                  !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !  Protocol-ID  !   SPI Size    !      Notify Message Type      !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                                                               !
+ * ~                Security Parameter Index (SPI)                 ~
+ * !                                                               !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                                                               !
+ * ~                       Notification Data                       ~
+ * !                                                               !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+static field_desc isan_fields[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_enum, 32/BITS_PER_BYTE, "DOI", &doi_names },
+    { ft_nat, 8/BITS_PER_BYTE, "protocol ID", NULL },	/* ??? really enum: ISAKMP, IPSEC, ESP, ... */
+    { ft_nat, 8/BITS_PER_BYTE, "SPI size", NULL },
+    { ft_enum, 16/BITS_PER_BYTE, "Notify Message Type", &notification_names },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_notification_desc = { "ISAKMP Notification Payload", isan_fields, sizeof(struct isakmp_notification) };
+
+/* ISAKMP Delete Payload
+ * layout from RFC 2408 "ISAKMP" section 3.15
+ * This is followed by a variable length SPI.
+ * Previous next payload: ISAKMP_NEXT_D
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !              Domain of Interpretation  (DOI)                  !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !  Protocol-Id  !   SPI Size    !           # of SPIs           !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                                                               !
+ * ~               Security Parameter Index(es) (SPI)              ~
+ * !                                                               !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+static field_desc isad_fields[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_enum, 32/BITS_PER_BYTE, "DOI", &doi_names },
+    { ft_nat, 8/BITS_PER_BYTE, "protocol ID", NULL },	/* ??? really enum: ISAKMP, IPSEC */
+    { ft_nat, 8/BITS_PER_BYTE, "SPI size", NULL },
+    { ft_nat, 16/BITS_PER_BYTE, "number of SPIs", NULL },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_delete_desc = { "ISAKMP Delete Payload", isad_fields, sizeof(struct isakmp_delete) };
+
+/* ISAKMP Vendor ID Payload
+ * layout from RFC 2408 "ISAKMP" section 3.15
+ * This is followed by a variable length VID.
+ * Previous next payload: ISAKMP_NEXT_VID
+ *                      1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                                                               !
+ * ~                        Vendor ID (VID)                        ~
+ * !                                                               !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+struct_desc isakmp_vendor_id_desc = { "ISAKMP Vendor ID Payload", isag_fields, sizeof(struct isakmp_generic) };
+
+/* MODECFG */
+/*
+ * From draft-dukes-ike-mode-cfg
+3.2. Attribute Payload
+                           1                   2                   3
+       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+     ! Next Payload  !   RESERVED    !         Payload Length        !
+     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+     !     Type      !   RESERVED    !           Identifier          ! 
+     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+     !                                                               !
+     ~                           Attributes                          ~
+     !                                                               !
+     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+*/
+static field_desc isaattr_fields[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_enum, 8/BITS_PER_BYTE, "Attr Msg Type", &attr_msg_type_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_nat, 16/BITS_PER_BYTE, "Identifier", NULL },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_attr_desc = { "ISAKMP Mode Attribute", isaattr_fields, sizeof(struct isakmp_mode_attr) };
+
+/* ISAKMP NAT-Traversal NAT-D
+ * layout from draft-ietf-ipsec-nat-t-ike-01.txt section 3.2
+ *
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !                 HASH of the address and port                  !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+struct_desc isakmp_nat_d = { "ISAKMP NAT-D Payload", isag_fields, sizeof(struct isakmp_generic) };
+
+/* ISAKMP NAT-Traversal NAT-OA
+ * layout from draft-ietf-ipsec-nat-t-ike-01.txt section 4.2
+ *
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * ! Next Payload  !   RESERVED    !         Payload Length        !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !   ID Type     !   RESERVED    !            RESERVED           !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * !         IPv4 (4 octets) or IPv6 address (16 octets)           !
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+static field_desc isanat_oa_fields[] = {
+    { ft_enum, 8/BITS_PER_BYTE, "next payload type", &payload_names },
+    { ft_mbz, 8/BITS_PER_BYTE, NULL, NULL },
+    { ft_len, 16/BITS_PER_BYTE, "length", NULL },
+    { ft_enum, 8/BITS_PER_BYTE, "ID type", &ident_names },
+    { ft_mbz, 24/BITS_PER_BYTE, NULL, NULL },
+    { ft_end, 0, NULL, NULL }
+};
+
+struct_desc isakmp_nat_oa = { "ISAKMP NAT-OA Payload", isanat_oa_fields, sizeof(struct isakmp_nat_oa) };
+
+/* descriptor for each payload type
+ *
+ * There is a slight problem in that some payloads differ, depending
+ * on the mode.  Since this is table only used for top-level payloads,
+ * Proposal and Transform payloads need not be handled.
+ * That leaves only Identification payloads as a problem.
+ * We make all these entries NULL
+ */
+struct_desc *const payload_descs[ISAKMP_NEXT_ROOF] = {
+    NULL,				/* 0 ISAKMP_NEXT_NONE (No other payload following) */
+    &isakmp_sa_desc,			/* 1 ISAKMP_NEXT_SA (Security Association) */
+    NULL,				/* 2 ISAKMP_NEXT_P (Proposal) */
+    NULL,				/* 3 ISAKMP_NEXT_T (Transform) */
+    &isakmp_keyex_desc,			/* 4 ISAKMP_NEXT_KE (Key Exchange) */
+    NULL,				/* 5 ISAKMP_NEXT_ID (Identification) */
+    &isakmp_ipsec_certificate_desc,	/* 6 ISAKMP_NEXT_CERT (Certificate) */
+    &isakmp_ipsec_cert_req_desc,	/* 7 ISAKMP_NEXT_CR (Certificate Request) */
+    &isakmp_hash_desc,			/* 8 ISAKMP_NEXT_HASH (Hash) */
+    &isakmp_signature_desc,		/* 9 ISAKMP_NEXT_SIG (Signature) */
+    &isakmp_nonce_desc,			/* 10 ISAKMP_NEXT_NONCE (Nonce) */
+    &isakmp_notification_desc,		/* 11 ISAKMP_NEXT_N (Notification) */
+    &isakmp_delete_desc,		/* 12 ISAKMP_NEXT_D (Delete) */
+    &isakmp_vendor_id_desc,		/* 13 ISAKMP_NEXT_VID (Vendor ID) */
+    &isakmp_attr_desc,			/* 14 ISAKMP_NEXT_ATTR (Mode Config) */
+    NULL,				/* 15 */
+    NULL,				/* 16 */
+    NULL,				/* 17 */
+    NULL,				/* 18 */
+    NULL,				/* 19 */
+    &isakmp_nat_d,              	/* 20=130 ISAKMP_NEXT_NATD (NAT-D) */
+    &isakmp_nat_oa,             	/* 20=131 ISAKMP_NEXT_NATOA (NAT-OA) */
+};
+
+void
+init_pbs(pb_stream *pbs, u_int8_t *start, size_t len, const char *name)
+{
+    pbs->container = NULL;
+    pbs->desc = NULL;
+    pbs->name = name;
+    pbs->start = pbs->cur = start;
+    pbs->roof = start + len;
+    pbs->lenfld = NULL;
+    pbs->lenfld_desc = NULL;
+}
+
+#ifdef DEBUG
+
+/* print a host struct
+ *
+ * This code assumes that the network and host structure
+ * members have the same alignment and size!  This requires
+ * that all padding be explicit.
+ */
+void
+DBG_print_struct(const char *label, const void *struct_ptr
+, struct_desc *sd, bool len_meaningful)
+{
+    bool immediate = FALSE;
+    const u_int8_t *inp = struct_ptr;
+    field_desc *fp;
+
+    DBG_log("%s%s:", label, sd->name);
+
+    for (fp = sd->fields; fp->field_type != ft_end; fp++)
+    {
+	int i = fp->size;
+	u_int32_t n = 0;
+
+	switch (fp->field_type)
+	{
+	case ft_mbz:	/* must be zero */
+	    inp += i;
+	    break;
+	case ft_nat:		/* natural number (may be 0) */
+	case ft_len:		/* length of this struct and any following crud */
+	case ft_lv:		/* length/value field of attribute */
+	case ft_enum:		/* value from an enumeration */
+	case ft_loose_enum:	/* value from an enumeration with only some names known */
+	case ft_af_enum:	/* Attribute Format + value from an enumeration */
+	case ft_af_loose_enum:	/* Attribute Format + value from an enumeration */
+	case ft_set:		/* bits representing set */
+	    switch (i)
+	    {
+	    case 8/BITS_PER_BYTE:
+		n = *(const u_int8_t *)inp;
+		break;
+	    case 16/BITS_PER_BYTE:
+		n = *(const u_int16_t *)inp;
+		break;
+	    case 32/BITS_PER_BYTE:
+		n = *(const u_int32_t *)inp;
+		break;
+	    default:
+		bad_case(i);
+	    }
+	    switch (fp->field_type)
+	    {
+	    case ft_len:	/* length of this struct and any following crud */
+	    case ft_lv:		/* length/value field of attribute */
+		if (!immediate && !len_meaningful)
+		    break;
+		/* FALL THROUGH */
+	    case ft_nat:	/* natural number (may be 0) */
+		DBG_log("   %s: %lu", fp->name, (unsigned long)n);
+		break;
+	    case ft_af_enum:	   /* Attribute Format + value from an enumeration */
+	    case ft_af_loose_enum: /* Attribute Format + value from an enumeration */
+		if ((n & ISAKMP_ATTR_AF_MASK) == ISAKMP_ATTR_AF_TV)
+		    immediate = TRUE;
+		/* FALL THROUGH */
+	    case ft_enum:	/* value from an enumeration */
+	    case ft_loose_enum:	/* value from an enumeration with only some names known */
+		DBG_log("   %s: %s", fp->name, enum_show(fp->desc, n));
+		break;
+	    case ft_set:	/* bits representing set */
+		DBG_log("   %s: %s", fp->name, bitnamesof(fp->desc, n));
+		break;
+	    default:
+		bad_case(fp->field_type);
+	    }
+	    inp += i;
+	    break;
+
+	case ft_raw:	/* bytes to be left in network-order */
+	    {
+		char m[50];	/* arbitrary limit on name width in log */
+
+		snprintf(m, sizeof(m), "   %s:", fp->name);
+		DBG_dump(m, inp, i);
+		inp += i;
+	    }
+	    break;
+	default:
+	    bad_case(fp->field_type);
+	}
+    }
+}
+
+static void
+DBG_prefix_print_struct(const pb_stream *pbs
+, const char *label, const void *struct_ptr
+, struct_desc *sd, bool len_meaningful)
+{
+    /* print out a title, with a prefix of asterisks to show
+     * the nesting level.
+     */
+    char space[40];	/* arbitrary limit on label+flock-of-* */
+    size_t len = strlen(label);
+
+    if (sizeof(space) <= len)
+    {
+	DBG_print_struct(label, struct_ptr, sd, len_meaningful);
+    }
+    else
+    {
+	const pb_stream *p = pbs;
+	char *pre = &space[sizeof(space) - (len + 1)];
+
+	strcpy(pre, label);
+
+	/* put at least one * out */
+	for (;;)
+	{
+	    if (pre <= space)
+		break;
+	    *--pre = '*';
+	    if (p == NULL)
+		break;
+	    p = p->container;
+	}
+	DBG_print_struct(pre, struct_ptr, sd, len_meaningful);
+    }
+}
+
+#endif
+
+/* "parse" a network struct into a host struct.
+ *
+ * This code assumes that the network and host structure
+ * members have the same alignment and size!  This requires
+ * that all padding be explicit.
+ *
+ * If obj_pbs is supplied, a new pb_stream is created for the
+ * variable part of the structure (this depends on their
+ * being one length field in the structure).  The cursor of this
+ * new PBS is set to after the parsed part of the struct.
+ *
+ * This routine returns TRUE iff it succeeds.
+ */
+
+bool
+in_struct(void *struct_ptr, struct_desc *sd
+, pb_stream *ins, pb_stream *obj_pbs)
+{
+    err_t ugh = NULL;
+    u_int8_t *cur = ins->cur;
+
+    if (ins->roof - cur < (ptrdiff_t)sd->size)
+    {
+	ugh = builddiag("not enough room in input packet for %s", sd->name);
+    }
+    else
+    {
+	u_int8_t *roof = cur + sd->size;    /* may be changed by a length field */
+	u_int8_t *outp = struct_ptr;
+	bool immediate = FALSE;
+	field_desc *fp;
+
+	for (fp = sd->fields; ugh == NULL; fp++)
+	{
+	    size_t i = fp->size;
+
+	    passert(ins->roof - cur >= (ptrdiff_t)i);
+	    passert(cur - ins->cur <= (ptrdiff_t)(sd->size - i));
+	    passert(outp - (cur - ins->cur) == struct_ptr);
+
+#if 0
+	    DBG(DBG_PARSING, DBG_log("%d %s"
+		, (int) (cur - ins->cur), fp->name == NULL? "" : fp->name));
+#endif
+	    switch (fp->field_type)
+	    {
+	    case ft_mbz:	/* must be zero */
+		for (; i != 0; i--)
+		{
+		    if (*cur++ != 0)
+		    {
+			ugh = builddiag("byte %d of %s must be zero, but is not"
+			    , (int) (cur - ins->cur), sd->name);
+			break;
+		    }
+		    *outp++ = '\0';	/* probably redundant */
+		}
+		break;
+
+	    case ft_nat:	   /* natural number (may be 0) */
+	    case ft_len:	   /* length of this struct and any following crud */
+	    case ft_lv:		   /* length/value field of attribute */
+	    case ft_enum:	   /* value from an enumeration */
+	    case ft_loose_enum:    /* value from an enumeration with only some names known */
+	    case ft_af_enum:	   /* Attribute Format + value from an enumeration */
+	    case ft_af_loose_enum: /* Attribute Format + value from an enumeration */
+	    case ft_set:	   /* bits representing set */
+	    {
+		u_int32_t n = 0;
+
+		for (; i != 0; i--)
+		    n = (n << BITS_PER_BYTE) | *cur++;
+
+		switch (fp->field_type)
+		{
+		case ft_len:	/* length of this struct and any following crud */
+		case ft_lv:	/* length/value field of attribute */
+		{
+		    u_int32_t len = fp->field_type == ft_len? n
+			: immediate? sd->size : n + sd->size;
+
+		    if (len < sd->size)
+		    {
+			ugh = builddiag("%s of %s is smaller than minimum"
+			    , fp->name, sd->name);
+		    }
+		    else if (pbs_left(ins) < len)
+		    {
+			ugh = builddiag("%s of %s is larger than can fit"
+			    , fp->name, sd->name);
+		    }
+		    else
+		    {
+			roof = ins->cur + len;
+		    }
+		    break;
+		}
+		case ft_af_loose_enum:	/* Attribute Format + value from an enumeration */
+		    if ((n & ISAKMP_ATTR_AF_MASK) == ISAKMP_ATTR_AF_TV)
+			immediate = TRUE;
+		    break;
+		case ft_af_enum:	/* Attribute Format + value from an enumeration */
+		    if ((n & ISAKMP_ATTR_AF_MASK) == ISAKMP_ATTR_AF_TV)
+			immediate = TRUE;
+		    /* FALL THROUGH */
+		case ft_enum:	/* value from an enumeration */
+		    if (enum_name(fp->desc, n) == NULL)
+		    {
+			ugh = builddiag("%s of %s has an unknown value: %lu"
+			    , fp->name, sd->name, (unsigned long)n);
+		    }
+		    /* FALL THROUGH */
+		case ft_loose_enum:	/* value from an enumeration with only some names known */
+		    break;
+		case ft_set:	/* bits representing set */
+		    if (!testset(fp->desc, n))
+		    {
+			ugh = builddiag("bitset %s of %s has unknown member(s): %s"
+			    , fp->name, sd->name, bitnamesof(fp->desc, n));
+		    }
+		    break;
+		default:
+			break;
+		}
+		i = fp->size;
+		switch (i)
+		{
+		case 8/BITS_PER_BYTE:
+		    *(u_int8_t *)outp = n;
+		    break;
+		case 16/BITS_PER_BYTE:
+		    *(u_int16_t *)outp = n;
+		    break;
+		case 32/BITS_PER_BYTE:
+		    *(u_int32_t *)outp = n;
+		    break;
+		default:
+		    bad_case(i);
+		}
+		outp += i;
+		break;
+	    }
+
+	    case ft_raw:	/* bytes to be left in network-order */
+		for (; i != 0; i--)
+		{
+		    *outp++ = *cur++;
+		}
+		break;
+
+	    case ft_end:	/* end of field list */
+		passert(cur == ins->cur + sd->size);
+		if (obj_pbs != NULL)
+		{
+		    init_pbs(obj_pbs, ins->cur, roof - ins->cur, sd->name);
+		    obj_pbs->container = ins;
+		    obj_pbs->desc = sd;
+		    obj_pbs->cur = cur;
+		}
+		ins->cur = roof;
+		DBG(DBG_PARSING
+		    , DBG_prefix_print_struct(ins, "parse ", struct_ptr, sd, TRUE));
+		return TRUE;
+
+	    default:
+		bad_case(fp->field_type);
+	    }
+	}
+    }
+
+    /* some failure got us here: report it */
+    loglog(RC_LOG_SERIOUS, ugh);
+    return FALSE;
+}
+
+bool
+in_raw(void *bytes, size_t len, pb_stream *ins, const char *name)
+{
+    if (pbs_left(ins) < len)
+    {
+	loglog(RC_LOG_SERIOUS, "not enough bytes left to get %s from %s", name, ins->name);
+	return FALSE;
+    }
+    else
+    {
+	if (bytes == NULL)
+	{
+	    DBG(DBG_PARSING
+		, DBG_log("skipping %u raw bytes of %s (%s)"
+		    , (unsigned) len, ins->name, name);
+		  DBG_dump(name, ins->cur, len));
+	}
+	else
+	{
+	    memcpy(bytes, ins->cur, len);
+	    DBG(DBG_PARSING
+		, DBG_log("parsing %u raw bytes of %s into %s"
+		    , (unsigned) len, ins->name, name);
+		  DBG_dump(name, bytes, len));
+	}
+	ins->cur += len;
+	return TRUE;
+    }
+}
+
+/* "emit" a host struct into a network packet.
+ *
+ * This code assumes that the network and host structure
+ * members have the same alignment and size!  This requires
+ * that all padding be explicit.
+ *
+ * If obj_pbs is non-NULL, its pbs describes a new output stream set up
+ * to contain the object.  The cursor will be left at the variable part.
+ * This new stream must subsequently be finalized by close_output_pbs().
+ *
+ * The value of any field of type ft_len is computed, not taken
+ * from the input struct.  The length is actually filled in when
+ * the object's output stream is finalized.  If obj_pbs is NULL,
+ * finalization is done by out_struct before it returns.
+ *
+ * This routine returns TRUE iff it succeeds.
+ */
+
+bool
+out_struct(const void *struct_ptr, struct_desc *sd
+, pb_stream *outs, pb_stream *obj_pbs)
+{
+    err_t ugh = NULL;
+    const u_int8_t *inp = struct_ptr;
+    u_int8_t *cur = outs->cur;
+
+    DBG(DBG_EMITTING
+	, DBG_prefix_print_struct(outs, "emit ", struct_ptr, sd, obj_pbs==NULL));
+
+    if (outs->roof - cur < (ptrdiff_t)sd->size)
+    {
+	ugh = builddiag("not enough room left in output packet to place %s"
+	    , sd->name);
+    }
+    else
+    {
+	bool immediate = FALSE;
+	pb_stream obj;
+	field_desc *fp;
+
+	obj.lenfld = NULL;  /* until a length field is discovered */
+	obj.lenfld_desc = NULL;
+
+	for (fp = sd->fields; ugh == NULL; fp++)
+	{
+	    size_t i = fp->size;
+
+	    passert(outs->roof - cur >= (ptrdiff_t)i);
+	    passert(cur - outs->cur <= (ptrdiff_t)(sd->size - i));
+	    passert(inp - (cur - outs->cur) == struct_ptr);
+
+#if 0
+	    DBG(DBG_EMITTING, DBG_log("%d %s"
+		, (int) (cur - outs->cur), fp->name == NULL? "" : fp->name);
+#endif
+	    switch (fp->field_type)
+	    {
+	    case ft_mbz:	/* must be zero */
+		inp += i;
+		for (; i != 0; i--)
+		    *cur++ = '\0';
+		break;
+	    case ft_nat:	   /* natural number (may be 0) */
+	    case ft_len:	   /* length of this struct and any following crud */
+	    case ft_lv:		   /* length/value field of attribute */
+	    case ft_enum:	   /* value from an enumeration */
+	    case ft_loose_enum:	   /* value from an enumeration with only some names known */
+	    case ft_af_enum:	   /* Attribute Format + value from an enumeration */
+	    case ft_af_loose_enum: /* Attribute Format + value from an enumeration */
+	    case ft_set:	   /* bits representing set */
+	    {
+		u_int32_t n = 0;
+
+		switch (i)
+		{
+		case 8/BITS_PER_BYTE:
+		    n = *(const u_int8_t *)inp;
+		    break;
+		case 16/BITS_PER_BYTE:
+		    n = *(const u_int16_t *)inp;
+		    break;
+		case 32/BITS_PER_BYTE:
+		    n = *(const u_int32_t *)inp;
+		    break;
+		default:
+		    bad_case(i);
+		}
+
+		switch (fp->field_type)
+		{
+		case ft_len:	/* length of this struct and any following crud */
+		case ft_lv:	/* length/value field of attribute */
+		    if (immediate)
+			break;	/* not a length */
+		    /* We can't check the length because it will likely
+		     * be filled in after variable part is supplied.
+		     * We do record where this is so that it can be
+		     * filled in by a subsequent close_output_pbs().
+		     */
+		    passert(obj.lenfld == NULL);	/* only one ft_len allowed */
+		    obj.lenfld = cur;
+		    obj.lenfld_desc = fp;
+		    break;
+		case ft_af_loose_enum: /* Attribute Format + value from an enumeration */
+		    if ((n & ISAKMP_ATTR_AF_MASK) == ISAKMP_ATTR_AF_TV)
+			immediate = TRUE;
+		    break;
+		case ft_af_enum:	/* Attribute Format + value from an enumeration */
+		    if ((n & ISAKMP_ATTR_AF_MASK) == ISAKMP_ATTR_AF_TV)
+			immediate = TRUE;
+		    /* FALL THROUGH */
+		case ft_enum:	/* value from an enumeration */
+		    if (enum_name(fp->desc, n) == NULL)
+		    {
+			ugh = builddiag("%s of %s has an unknown value: %lu"
+			    , fp->name, sd->name, (unsigned long)n);
+		    }
+		    /* FALL THROUGH */
+		case ft_loose_enum:	/* value from an enumeration with only some names known */
+		    break;
+		case ft_set:	/* bits representing set */
+		    if (!testset(fp->desc, n))
+		    {
+			ugh = builddiag("bitset %s of %s has unknown member(s): %s"
+			    , fp->name, sd->name, bitnamesof(fp->desc, n));
+		    }
+		    break;
+		default:
+		    break;
+		}
+
+		while (i-- != 0)
+		{
+		    cur[i] = (u_int8_t)n;
+		    n >>= BITS_PER_BYTE;
+		}
+		inp += fp->size;
+		cur += fp->size;
+		break;
+	    }
+	    case ft_raw:	/* bytes to be left in network-order */
+		for (; i != 0; i--)
+		    *cur++ = *inp++;
+		break;
+	    case ft_end:	/* end of field list */
+		passert(cur == outs->cur + sd->size);
+
+		obj.container = outs;
+		obj.desc = sd;
+		obj.name = sd->name;
+		obj.start = outs->cur;
+		obj.cur = cur;
+		obj.roof = outs->roof;	/* limit of possible */
+		/* obj.lenfld and obj.lenfld_desc already set */
+
+		if (obj_pbs == NULL)
+		{
+		    close_output_pbs(&obj); /* fill in length field, if any */
+		}
+		else
+		{
+		    /* We set outs->cur to outs->roof so that
+		     * any attempt to output something into outs
+		     * before obj is closed will trigger an error.
+		     */
+		    outs->cur = outs->roof;
+
+		    *obj_pbs = obj;
+		}
+		return TRUE;
+
+	    default:
+		bad_case(fp->field_type);
+	    }
+	}
+    }
+
+    /* some failure got us here: report it */
+    loglog(RC_LOG_SERIOUS, ugh);	/* ??? serious, but errno not relevant */
+    return FALSE;
+}
+
+bool
+out_generic(u_int8_t np, struct_desc *sd
+, pb_stream *outs, pb_stream *obj_pbs)
+{
+    struct isakmp_generic gen;
+
+    passert(sd->fields == isakmp_generic_desc.fields);
+    gen.isag_np = np;
+    return out_struct(&gen, sd, outs, obj_pbs);
+}
+
+bool
+out_generic_raw(u_int8_t np, struct_desc *sd
+, pb_stream *outs, const void *bytes, size_t len, const char *name)
+{
+    pb_stream pbs;
+
+    if (!out_generic(np, sd, outs, &pbs)
+    || !out_raw(bytes, len, &pbs, name))
+	return FALSE;
+    close_output_pbs(&pbs);
+    return TRUE;
+}
+
+bool
+out_raw(const void *bytes, size_t len, pb_stream *outs, const char *name)
+{
+    if (pbs_left(outs) < len)
+    {
+	loglog(RC_LOG_SERIOUS, "not enough room left to place %lu bytes of %s in %s"
+	    , (unsigned long) len, name, outs->name);
+	return FALSE;
+    }
+    else
+    {
+	DBG(DBG_EMITTING
+	    , DBG_log("emitting %u raw bytes of %s into %s"
+		, (unsigned) len, name, outs->name);
+	      DBG_dump(name, bytes, len));
+	memcpy(outs->cur, bytes, len);
+	outs->cur += len;
+	return TRUE;
+    }
+}
+
+bool
+out_zero(size_t len, pb_stream *outs, const char *name)
+{
+    if (pbs_left(outs) < len)
+    {
+	loglog(RC_LOG_SERIOUS, "not enough room left to place %s in %s", name, outs->name);
+	return FALSE;
+    }
+    else
+    {
+	DBG(DBG_EMITTING, DBG_log("emitting %u zero bytes of %s into %s"
+	    , (unsigned) len, name, outs->name));
+	memset(outs->cur, 0x00, len);
+	outs->cur += len;
+	return TRUE;
+    }
+}
+
+/* Record current length.
+ * Note: currently, this may be repeated any number of times;
+ * the last one wins.
+ */
+void
+close_output_pbs(pb_stream *pbs)
+{
+    if (pbs->lenfld != NULL)
+    {
+	u_int32_t len = pbs_offset(pbs);
+	int i = pbs->lenfld_desc->size;
+
+	if (pbs->lenfld_desc->field_type == ft_lv)
+	    len -= sizeof(struct isakmp_attribute);
+	DBG(DBG_EMITTING, DBG_log("emitting length of %s: %lu"
+	    , pbs->name, (unsigned long) len));
+	while (i-- != 0)
+	{
+	    pbs->lenfld[i] = (u_int8_t)len;
+	    len >>= BITS_PER_BYTE;
+	}
+    }
+    if (pbs->container != NULL)
+	pbs->container->cur = pbs->cur;	/* pass space utilization up */
+}