diff options
Diffstat (limited to 'src/libcharon/encoding/message.c')
| -rw-r--r-- | src/libcharon/encoding/message.c | 106 |
1 files changed, 105 insertions, 1 deletions
diff --git a/src/libcharon/encoding/message.c b/src/libcharon/encoding/message.c index cecb55470..435b98205 100644 --- a/src/libcharon/encoding/message.c +++ b/src/libcharon/encoding/message.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2006-2013 Tobias Brunner + * Copyright (C) 2006-2014 Tobias Brunner * Copyright (C) 2005-2010 Martin Willi * Copyright (C) 2010 revosec AG * Copyright (C) 2006 Daniel Roethlisberger @@ -23,6 +23,7 @@ #include "message.h" #include <library.h> +#include <collections/array.h> #include <daemon.h> #include <sa/ikev1/keymat_v1.h> #include <encoding/generator.h> @@ -33,6 +34,7 @@ #include <encoding/payloads/encrypted_payload.h> #include <encoding/payloads/unknown_payload.h> #include <encoding/payloads/cp_payload.h> +#include <encoding/payloads/fragment_payload.h> /** * Max number of notify payloads per IKEv2 message @@ -1652,6 +1654,107 @@ METHOD(message_t, generate, status_t, return SUCCESS; } +/** + * Creates a (basic) clone of the given message + */ +static message_t *clone_message(private_message_t *this) +{ + message_t *message; + host_t *src, *dst; + + src = this->packet->get_source(this->packet); + dst = this->packet->get_destination(this->packet); + + message = message_create(this->major_version, this->minor_version); + message->set_message_id(message, this->message_id); + message->set_request(message, this->is_request); + message->set_source(message, src->clone(src)); + message->set_destination(message, dst->clone(dst)); + message->set_exchange_type(message, this->exchange_type); + return message; +} + +/** + * Create a single fragment with the given data + */ +static message_t *create_fragment(private_message_t *this, u_int8_t num, + bool last, chunk_t data) +{ + fragment_payload_t *fragment; + message_t *message; + + fragment = fragment_payload_create_from_data(num, last, data); + message = clone_message(this); + message->add_payload(message, (payload_t*)fragment); + return message; +} + +/** + * Destroy all messages in the given array + */ +CALLBACK(destroy_fragments, void, + array_t *fragments) +{ + array_destroy_offset(fragments, offsetof(message_t, destroy)); +} + +METHOD(message_t, fragment, status_t, + private_message_t *this, size_t frag_len, enumerator_t **fragments) +{ + array_t *messages; + message_t *fragment; + u_int8_t num, count; + host_t *src, *dst; + chunk_t data; + size_t len; + + if (!is_encoded(this) || this->major_version == IKEV2_MAJOR_VERSION) + { + return INVALID_STATE; + } + + src = this->packet->get_source(this->packet); + dst = this->packet->get_destination(this->packet); + if (!frag_len) + { + frag_len = (src->get_family(src) == AF_INET) ? 576 : 1280; + } + /* frag_len is the complete IP datagram length, account for overhead (we + * assume no IP options/extension headers are used) */ + frag_len -= (src->get_family(src) == AF_INET) ? 20 : 40; + /* 8 (UDP header) + 28 (IKE header) */ + frag_len -= 36; + if (dst->get_port(dst) != IKEV2_UDP_PORT && + src->get_port(src) != IKEV2_UDP_PORT) + { /* reduce length due to non-ESP marker */ + frag_len -= 4; + } + + data = this->packet->get_data(this->packet); + if (data.len <= frag_len) + { + return ALREADY_DONE; + } + /* overhead for the fragmentation payload header */ + frag_len -= 8; + + count = data.len / frag_len + (data.len % frag_len ? 1 : 0); + messages = array_create(0, count); + DBG2(DBG_ENC, "splitting IKE message with length of %zu bytes into " + "%hhu fragments", data.len, count); + for (num = 1; num <= count; num++) + { + len = min(data.len, frag_len); + fragment = create_fragment(this, num, num == count, + chunk_create(data.ptr, len)); + array_insert(messages, ARRAY_TAIL, fragment); + data = chunk_skip(data, len); + } + *fragments = enumerator_create_cleaner(array_create_enumerator(messages), + destroy_fragments, messages); + return SUCCESS; +} + METHOD(message_t, get_packet, packet_t*, private_message_t *this) { @@ -2195,6 +2298,7 @@ message_t *message_create_from_packet(packet_t *packet) .disable_sort = _disable_sort, .generate = _generate, .is_encoded = _is_encoded, + .fragment = _fragment, .set_source = _set_source, .get_source = _get_source, .set_destination = _set_destination, |