- parser successfully parses an ike_header

- no doxygen yet
This commit is contained in:
Martin Willi 2005-11-10 19:19:56 +00:00
parent 27e308739b
commit 3d40ec7a68
2 changed files with 388 additions and 12 deletions

View file

@ -21,10 +21,71 @@
*/
#include <stdlib.h>
#include <arpa/inet.h>
#include "allocator.h"
#include "types.h"
#include "parser.h"
#include "logger.h"
typedef struct private_parser_context_s private_parser_context_t;
struct private_parser_context_s {
/**
* Public members
*/
parser_context_t public;
/**
* Current bit for reading in input data
*/
u_int8_t bit_pos;
/**
* Current byte for reading in input data
*/
u_int8_t *byte_pos;
/**
* input data to parse
*/
u_int8_t *input;
/**
* roof of input
*/
u_int8_t *input_roof;
};
static status_t parser_context_destroy(private_parser_context_t *this)
{
allocator_free(this);
return SUCCESS;
}
static private_parser_context_t *parser_context_create(chunk_t input)
{
private_parser_context_t *this = allocator_alloc_thing(private_parser_context_t);
if (this == NULL)
{
return NULL;
}
this->public.destroy = (status_t(*)(parser_context_t*)) parser_context_destroy;
this->input = input.ptr;
this->byte_pos = input.ptr;
this->bit_pos = 0;
this->input_roof = input.ptr + input.len;
return this;
}
/**
* Private data of a parser_t object
@ -37,8 +98,308 @@ struct private_parser_s {
*/
parser_t public;
/* private functions and fields */
/**
* list of payloads and their description
*/
payload_info_t **payload_infos;
/**
* logger object
*/
logger_t *logger;
};
static private_parser_context_t *create_context(private_parser_t *this, chunk_t data)
{
private_parser_context_t *context = parser_context_create(data);
return context;
}
static status_t parse_payload(private_parser_t *this, private_parser_context_t *context, payload_type_t payload_type, void **data_struct)
{
payload_info_t *payload_info = NULL;
/* find payload in null terminated list*/
payload_info = *(this->payload_infos);
while (payload_info)
{
if (payload_info->payload_type == payload_type)
{
void *output;
int current;
/* ok, do the parsing */
output = allocator_alloc(payload_info->data_struct_length);
for (current = 0; current < payload_info->encoding_rules_count; current++)
{
encoding_rule_t *rule = &(payload_info->ecoding_rules[current]);
switch (rule->type)
{
case U_INT_4:
{
u_int8_t *output_pos = output + rule->offset;
if (context->byte_pos + sizeof(u_int8_t) > context->input_roof)
{
this->logger->log(this->logger, ERROR, "not enough input to parse U_INT_4");
allocator_free(output);
return PARSE_ERROR;
}
switch (context->bit_pos)
{
case 0:
*output_pos = *(context->byte_pos) >> 4;
context->bit_pos = 4;
break;
case 4:
*output_pos = *(context->byte_pos) & 0x0F;
context->bit_pos = 0;
context->byte_pos++;
break;
default:
this->logger->log(this->logger, ERROR, "found rule U_INT_4 on bitpos %d", context->bit_pos);
allocator_free(output);
return PARSE_ERROR;
}
break;
}
case U_INT_8:
{
u_int8_t *output_pos = output + rule->offset;
if (context->byte_pos + sizeof(u_int8_t) > context->input_roof)
{
this->logger->log(this->logger, ERROR, "not enough input to parse U_INT_8");
allocator_free(output);
return PARSE_ERROR;
}
if (context->bit_pos)
{
this->logger->log(this->logger, ERROR, "found rule U_INT_8 on bitpos %d", context->bit_pos);
allocator_free(output);
return PARSE_ERROR;
}
*output_pos = *(context->byte_pos);
context->byte_pos++;
break;
}
case U_INT_16:
{
u_int16_t *output_pos = output + rule->offset;
if (context->byte_pos + sizeof(u_int16_t) > context->input_roof)
{
this->logger->log(this->logger, ERROR, "not enough input to parse U_INT_16");
allocator_free(output);
return PARSE_ERROR;
}
if (context->bit_pos)
{
this->logger->log(this->logger, ERROR, "found rule U_INT_16 on bitpos %d", context->bit_pos);
allocator_free(output);
return PARSE_ERROR;
}
if ((int)context->byte_pos % 2)
{
this->logger->log(this->logger, ERROR, "found rule U_INT_16 on odd bytepos");
allocator_free(output);
return PARSE_ERROR;
}
*output_pos = ntohs(*((u_int16_t*)context->byte_pos));
context->byte_pos += 2;
break;
}
case U_INT_32:
{
u_int32_t *output_pos = output + rule->offset;
if (context->byte_pos + sizeof(u_int32_t) > context->input_roof)
{
this->logger->log(this->logger, ERROR, "not enough input to parse U_INT_32");
allocator_free(output);
return PARSE_ERROR;
}
if (context->bit_pos)
{
this->logger->log(this->logger, ERROR, "found rule U_INT_32 on bitpos %d", context->bit_pos);
allocator_free(output);
return PARSE_ERROR;
}
if ((int)context->byte_pos % 4)
{
this->logger->log(this->logger, ERROR, "found rule U_INT_32 on unaligned bytepos");
allocator_free(output);
return PARSE_ERROR;
}
*output_pos = ntohl(*((u_int32_t*)context->byte_pos));
context->byte_pos += 4;
break;
}
case U_INT_64:
{
u_int32_t *output_pos = output + rule->offset;
if (context->byte_pos + 2 * sizeof(u_int32_t) > context->input_roof)
{
this->logger->log(this->logger, ERROR, "not enough input to parse U_INT_64");
allocator_free(output);
return PARSE_ERROR;
}
if (context->bit_pos)
{
this->logger->log(this->logger, ERROR, "found rule U_INT_64 on bitpos %d", context->bit_pos);
allocator_free(output);
return PARSE_ERROR;
}
if ((int)context->byte_pos % 8)
{
this->logger->log(this->logger, ERROR, "found rule U_INT_64 on unaligned bytepos");
allocator_free(output);
return PARSE_ERROR;
}
/* assuming little endian host order */
*(output_pos + 1) = ntohl(*((u_int32_t*)context->byte_pos));
context->byte_pos += 4;
*output_pos = ntohl(*((u_int32_t*)context->byte_pos));
context->byte_pos += 4;
break;
}
case RESERVED_BIT:
{
if (context->byte_pos > context->input_roof)
{
this->logger->log(this->logger, ERROR, "not enough input to parse RESERVED_BIT");
allocator_free(output);
return PARSE_ERROR;
}
context->bit_pos = (context->bit_pos + 1) % 8;
if (context->bit_pos == 0)
{
context->byte_pos++;
}
break;
}
case RESERVED_BYTE:
{
if (context->byte_pos > context->input_roof)
{
this->logger->log(this->logger, ERROR, "not enough input to parse RESERVED_BYTE");
allocator_free(output);
return PARSE_ERROR;
}
if (context->bit_pos)
{
this->logger->log(this->logger, ERROR, "found rule RESERVED_BYTE on bitpos %d", context->bit_pos);
allocator_free(output);
return PARSE_ERROR;
}
context->byte_pos++;
break;
}
case FLAG:
{
bool *output_pos = output + rule->offset;
u_int8_t mask;
if (context->byte_pos > context->input_roof)
{
this->logger->log(this->logger, ERROR, "not enough input to parse FLAG");
allocator_free(output);
return PARSE_ERROR;
}
mask = 0x01 << (7 - context->bit_pos);
*output_pos = *context->byte_pos & mask;
if (*output_pos)
{
/* set to a "clean", comparable true */
*output_pos = TRUE;
}
context->bit_pos = (context->bit_pos + 1) % 8;
if (context->bit_pos == 0)
{
context->byte_pos++;
}
break;
}
case LENGTH:
{
u_int32_t *output_pos = output + rule->offset;
if (context->byte_pos + sizeof(u_int32_t) > context->input_roof)
{
this->logger->log(this->logger, ERROR, "not enough input to parse LENGTH");
allocator_free(output);
return PARSE_ERROR;
}
if (context->bit_pos)
{
this->logger->log(this->logger, ERROR, "found rule LENGTH on bitpos %d", context->bit_pos);
allocator_free(output);
return PARSE_ERROR;
}
if ((int)context->byte_pos % 4)
{
this->logger->log(this->logger, ERROR, "found rule LENGTH on unaligned bytepos");
allocator_free(output);
return PARSE_ERROR;
}
*output_pos = ntohl(*((u_int32_t*)context->byte_pos));
context->byte_pos += 4;
break;
}
case SPI_SIZE:
{
}
default:
{
this->logger->log(this->logger, ERROR, "parser found unknown type");
allocator_free(output);
return PARSE_ERROR;
}
}
}
*data_struct = output;
return SUCCESS;
}
payload_info++;
}
this->logger->log(this->logger, ERROR, "Payload not supported");
return NOT_SUPPORTED;
}
static status_t destroy(private_parser_t *this)
{
this->logger->destroy(this->logger);
allocator_free(this);
return SUCCESS;
}
parser_t *parser_create(payload_info_t **payload_infos)
{
private_parser_t *this = allocator_alloc_thing(private_parser_t);
if (this == NULL)
{
return NULL;
}
this->logger = logger_create("parser", ALL);
if (this->logger == NULL)
{
allocator_free(this);
return NULL;
}
this->public.create_context = (parser_context_t*(*)(parser_t*,chunk_t)) create_context;
this->public.parse_payload = (status_t(*)(parser_t*,parser_context_t*,payload_type_t,void**)) parse_payload;
this->public.destroy = (status_t(*)(parser_t*)) destroy;
this->payload_infos = payload_infos;
return (parser_t*)this;
}

View file

@ -27,6 +27,14 @@
#include "encodings.h"
typedef struct parser_context_s parser_context_t;
struct parser_context_s {
status_t (*destroy) (parser_context_t *this);
};
/**
* @brief A parser_t object which parses payloads of specific type
@ -36,22 +44,29 @@ typedef struct parser_s parser_t;
struct parser_s {
/**
* @brief Generates a specific payload from given data struct
* @brief parses a chunk and generates a usable data struct
*
* Remember: Header and substructures are also seen as payloads
*
* @param generator generator object
* @return SUCCESSFUL if succeeded,
* NOT_SUPPORTED if payload_type is not supported
* OUT_OF_RES if out of ressources
* @param parser parser Object
* @param payload_type definition of payload including encoding_rule
* @param data chunk of data to parse
* @param[out] allocated structure with parsed data
* @return
* - SUCCESSFUL if succeeded,
* - NOT_SUPPORTED if payload_type is not supported
* - OUT_OF_RES if out of ressources
* - PARSE_ERROR if corrupted data found
*/
status_t (*parse_payload) (parser_t *this, payload_type_t payload_type, chunk_t *data, void *data_struct);
parser_context_t *(*create_context) (parser_t *this, chunk_t data);
status_t (*parse_payload) (parser_t *this, parser_context_t* context, payload_type_t payload_type, void **data_struct);
/**
* @brief Destroys a generator object
* @brief Destroys a parser object
*
* @param generator generator object
* @return SUCCESSFUL if succeeded, FAILED otherwise
* @param parser parser object
* @return
* - SUCCESSFUL in any case
*/
status_t (*destroy) (parser_t *this);
};
@ -60,6 +75,6 @@ struct parser_s {
* Constructor to create a parser
*
*/
parser_t *parser_create(payload_info_t ** payload_infos);
parser_t *parser_create(payload_info_t **payload_infos);
#endif /*PARSER_H_*/