diff options
Diffstat (limited to 'src/libimcv/seg/seg_env.c')
-rw-r--r-- | src/libimcv/seg/seg_env.c | 306 |
1 files changed, 306 insertions, 0 deletions
diff --git a/src/libimcv/seg/seg_env.c b/src/libimcv/seg/seg_env.c new file mode 100644 index 000000000..c47ce2934 --- /dev/null +++ b/src/libimcv/seg/seg_env.c @@ -0,0 +1,306 @@ +/* + * Copyright (C) 2014 Andreas Steffen + * HSR Hochschule fuer Technik Rapperswil + * + * 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. + */ + +#include "seg_env.h" + +#include "imcv.h" +#include "pa_tnc/pa_tnc_msg.h" +#include "ietf/ietf_attr_pa_tnc_error.h" +#include "tcg/seg/tcg_seg_attr_seg_env.h" + +#include <utils/debug.h> +#include <bio/bio_reader.h> +#include <bio/bio_writer.h> + +#define BASE_ATTR_ID_PREFIX 0xFF + +typedef struct private_seg_env_t private_seg_env_t; + +/** + * Private data of a seg_env_t object. + */ +struct private_seg_env_t { + + /** + * Public seg_env_t interface. + */ + seg_env_t public; + + /** + * Base Attribute ID + */ + uint32_t base_attr_id; + + /** + * Base Attribute + */ + pa_tnc_attr_t *base_attr; + + /** + * Base Attribute Info to be used for PA-TNC error messages + */ + u_char base_attr_info[8]; + + /** + * Base Attribute needs more segment data + */ + bool need_more; + + /** + * Pointer to remaining attribute data to be sent + */ + chunk_t data; + + /** + * Maximum PA-TNC attribute segment size + */ + uint32_t max_seg_size; + +}; + +METHOD(seg_env_t, get_base_attr_id, uint32_t, + private_seg_env_t *this) +{ + return this->base_attr_id; +} + +METHOD(seg_env_t, get_base_attr, pa_tnc_attr_t*, + private_seg_env_t *this) +{ + return this->need_more ? NULL : this->base_attr->get_ref(this->base_attr); +} + +METHOD(seg_env_t, get_base_attr_info, chunk_t, + private_seg_env_t *this) +{ + return chunk_create(this->base_attr_info, 8); +} + +METHOD(seg_env_t, first_segment, pa_tnc_attr_t*, + private_seg_env_t *this) +{ + pa_tnc_attr_t *seg_env_attr; + bio_writer_t *writer; + pen_type_t type; + chunk_t segment_data, value; + uint8_t flags, seg_env_flags; + + /* get components of base attribute header and data */ + flags = this->base_attr->get_noskip_flag(this->base_attr) ? + PA_TNC_ATTR_FLAG_NOSKIP : PA_TNC_ATTR_FLAG_NONE; + type = this->base_attr->get_type(this->base_attr); + + /* attribute data going into the first segment */ + segment_data = this->data; + segment_data.len = this->max_seg_size - PA_TNC_ATTR_HEADER_SIZE; + + /* build encoding of the base attribute header and first segment data */ + writer = bio_writer_create(this->max_seg_size); + writer->write_uint8 (writer, flags); + writer->write_uint24(writer, type.vendor_id); + writer->write_uint32(writer, type.type); + writer->write_uint32(writer, PA_TNC_ATTR_HEADER_SIZE + this->data.len); + writer->write_data (writer, segment_data); + value = writer->extract_buf(writer); + writer->destroy(writer); + this->data = chunk_skip(this->data, segment_data.len); + + DBG2(DBG_TNC, "creating first segment for base attribute ID %d (%d bytes)", + this->base_attr_id, this->max_seg_size); + + seg_env_flags = SEG_ENV_FLAG_START | SEG_ENV_FLAG_MORE; + seg_env_attr = tcg_seg_attr_seg_env_create(value, seg_env_flags, + this->base_attr_id); + chunk_free(&value); + + return seg_env_attr; +} + +METHOD(seg_env_t, next_segment, pa_tnc_attr_t*, + private_seg_env_t *this, bool *last) +{ + pa_tnc_attr_t *seg_env_attr; + chunk_t segment_data; + uint8_t seg_env_flags; + bool is_last_segment; + + if (this->data.len == 0) + { + /* no more attribute data to segment available */ + return NULL; + } + + /* attribute data going into the next segment */ + segment_data = this->data; + segment_data.len = min(this->max_seg_size, this->data.len); + this->data = chunk_skip(this->data, segment_data.len); + + is_last_segment = (this->data.len == 0); + if (last) + { + *last = is_last_segment; + } + DBG2(DBG_TNC, "creating %s segment for base attribute ID %d (%d bytes)", + is_last_segment ? "last" : "next", this->base_attr_id, + segment_data.len); + + seg_env_flags = is_last_segment ? SEG_ENV_FLAG_NONE : SEG_ENV_FLAG_MORE; + seg_env_attr = tcg_seg_attr_seg_env_create(segment_data, seg_env_flags, + this->base_attr_id); + + return seg_env_attr; +} + +METHOD(seg_env_t, add_segment, bool, + private_seg_env_t *this, chunk_t segment, pa_tnc_attr_t **error) +{ + pen_type_t type, error_code; + uint32_t attr_offset; + chunk_t msg_info; + status_t status; + + this->base_attr->add_segment(this->base_attr, segment); + status = this->base_attr->process(this->base_attr, &attr_offset); + + if (status != SUCCESS && status != NEED_MORE) + { + type = this->base_attr->get_type(this->base_attr); + if (type.vendor_id == PEN_IETF && type.type == IETF_ATTR_PA_TNC_ERROR) + { + /* error while processing a PA-TNC error attribute - abort */ + return FALSE; + } + error_code = pen_type_create(PEN_IETF, PA_ERROR_INVALID_PARAMETER); + msg_info = get_base_attr_info(this); + *error = ietf_attr_pa_tnc_error_create_with_offset(error_code, + msg_info, PA_TNC_ATTR_HEADER_SIZE + attr_offset); + return FALSE; + } + this->need_more = (status == NEED_MORE); + + return TRUE; +} + +METHOD(seg_env_t, destroy, void, + private_seg_env_t *this) +{ + DESTROY_IF(this->base_attr); + free(this); +} + +/** + * See header + */ +seg_env_t *seg_env_create(uint32_t base_attr_id, pa_tnc_attr_t *base_attr, + uint32_t max_seg_size) +{ + private_seg_env_t *this; + chunk_t value; + + base_attr->build(base_attr); + value = base_attr->get_value(base_attr); + + /** + * The PA-TNC attribute header must not be segmented and + * there must be at least a first and one next segment + */ + if (max_seg_size < PA_TNC_ATTR_HEADER_SIZE || + max_seg_size >= PA_TNC_ATTR_HEADER_SIZE + value.len) + { + return NULL; + } + + INIT(this, + .public = { + .get_base_attr_id = _get_base_attr_id, + .get_base_attr = _get_base_attr, + .get_base_attr_info = _get_base_attr_info, + .first_segment = _first_segment, + .next_segment = _next_segment, + .add_segment = _add_segment, + .destroy = _destroy, + }, + .base_attr_id = base_attr_id, + .base_attr = base_attr->get_ref(base_attr), + .max_seg_size = max_seg_size, + .data = base_attr->get_value(base_attr), + ); + + return &this->public; +} + +/** + * See header + */ +seg_env_t *seg_env_create_from_data(uint32_t base_attr_id, chunk_t data, + uint32_t max_seg_size, pa_tnc_attr_t** error) +{ + private_seg_env_t *this; + pen_type_t type, error_code; + bio_reader_t *reader; + chunk_t msg_info; + uint32_t offset = 0, attr_offset; + status_t status; + + INIT(this, + .public = { + .get_base_attr_id = _get_base_attr_id, + .get_base_attr = _get_base_attr, + .get_base_attr_info = _get_base_attr_info, + .first_segment = _first_segment, + .next_segment = _next_segment, + .add_segment = _add_segment, + .destroy = _destroy, + }, + .base_attr_id = base_attr_id, + .max_seg_size = max_seg_size, + ); + + /* create info field to be used by PA-TNC error messages */ + memset(this->base_attr_info, 0xff, 4); + htoun32(this->base_attr_info + 4, base_attr_id); + msg_info = get_base_attr_info(this); + + /* extract from base attribute segment from data */ + reader = bio_reader_create(data); + this->base_attr = imcv_pa_tnc_attributes->create(imcv_pa_tnc_attributes, + reader, TRUE, &offset, msg_info, error); + reader->destroy(reader); + + if (!this->base_attr) + { + destroy(this); + return NULL; + } + status = this->base_attr->process(this->base_attr, &attr_offset); + + if (status != SUCCESS && status != NEED_MORE) + { + type = this->base_attr->get_type(this->base_attr); + if (!(type.vendor_id == PEN_IETF && + type.type == IETF_ATTR_PA_TNC_ERROR)) + { + error_code = pen_type_create(PEN_IETF, PA_ERROR_INVALID_PARAMETER); + *error = ietf_attr_pa_tnc_error_create_with_offset(error_code, + msg_info, PA_TNC_ATTR_HEADER_SIZE + attr_offset); + } + destroy(this); + return NULL; + } + this->need_more = (status == NEED_MORE); + + return &this->public; +} + |