/**
* @brief Execute the rule.
*
* @param[in] ib Ironbee engine
* @param[in] tx The transaction.
* @param[in,out] User data. A @c pcre_rule_data_t.
* @param[in] flags Operator instance flags
* @param[in] field The field content.
* @param[out] result The result.
* @returns IB_OK most times. IB_EALLOC when a memory allocation error handles.
*/
static ib_status_t dfa_operator_execute(ib_engine_t *ib,
ib_tx_t *tx,
const ib_rule_t *rule,
void *data,
ib_flags_t flags,
ib_field_t *field,
ib_num_t *result)
{
IB_FTRACE_INIT();
assert(tx);
assert(data);
int matches;
ib_status_t ib_rc;
const int ovecsize = 3 * MATCH_MAX;
dfa_rule_data_t *rule_data;
int *ovector;
const char* subject;
size_t subject_len;
const ib_bytestr_t* bytestr;
dfa_workspace_t *dfa_workspace;
int options; /* dfa exec options. */
ovector = (int *)malloc(ovecsize*sizeof(*ovector));
if (ovector==NULL) {
IB_FTRACE_RET_STATUS(IB_EALLOC);
}
/* Pull out the rule data. */
rule_data = (dfa_rule_data_t *)data;
if (field->type == IB_FTYPE_NULSTR) {
ib_rc = ib_field_value(field, ib_ftype_nulstr_out(&subject));
if (ib_rc != IB_OK) {
free(ovector);
IB_FTRACE_RET_STATUS(ib_rc);
}
subject_len = strlen(subject);
}
else if (field->type == IB_FTYPE_BYTESTR) {
ib_rc = ib_field_value(field, ib_ftype_bytestr_out(&bytestr));
if (ib_rc != IB_OK) {
free(ovector);
IB_FTRACE_RET_STATUS(ib_rc);
}
subject_len = ib_bytestr_length(bytestr);
subject = (const char *) ib_bytestr_const_ptr(bytestr);
}
else {
free(ovector);
IB_FTRACE_RET_STATUS(IB_EINVAL);
}
/* Debug block. Escapes a string and prints it to the log.
* Memory is freed. */
if (ib_log_get_level(ib) >= 9) {
/* Worst case, we can have a string that is 4x larger.
* Consider if a string of 0xF7 is passed. That single character
* will expand to a string of 4 printed characters +1 for the \0
* character. */
char *debug_str = ib_util_hex_escape(subject, subject_len);
if ( debug_str != NULL ) {
ib_log_debug3_tx(tx, "Matching against: %s", debug_str);
free( debug_str );
}
}
/* Get the per-tx workspace data for this rule data id. */
ib_rc = get_dfa_tx_data(tx, rule_data->id, &dfa_workspace);
if (ib_rc == IB_ENOENT) {
options = PCRE_PARTIAL_SOFT;
ib_rc = alloc_dfa_tx_data(tx, rule_data->id, &dfa_workspace);
if (ib_rc != IB_OK) {
free(ovector);
ib_log_error_tx(tx, "Unexpected error creating tx storage "
"for dfa operator %s",
rule_data->id);
IB_FTRACE_RET_STATUS(ib_rc);
}
ib_log_debug_tx(tx,
"Created DFA workspace at %p for id %s.",
dfa_workspace,
rule_data->id);
}
else if (ib_rc == IB_OK) {
options = PCRE_PARTIAL_SOFT | PCRE_DFA_RESTART;
ib_log_debug_tx(tx,
"Reusing existing DFA workspace %p for id %s.",
dfa_workspace,
rule_data->id);
}
else {
free(ovector);
ib_log_error_tx(tx,
"Unexpected error fetching dfa data "
"for dfa operator %s",
rule_data->id);
IB_FTRACE_RET_STATUS(ib_rc);
}
/* Actually do the DFA match. */
matches = pcre_dfa_exec(rule_data->cpatt,
rule_data->edata,
subject,
subject_len,
0, /* Starting offset. */
options,
ovector,
ovecsize,
dfa_workspace->workspace,
dfa_workspace->wscount);
if (matches >= 0) {
ib_rc = IB_OK;
*result = 1;
}
else if (matches == PCRE_ERROR_PARTIAL) {
ib_log_debug2_tx(tx, "Partial match found, but not a full match.");
ib_rc = IB_OK;
*result = 0;
}
else if (matches == PCRE_ERROR_NOMATCH) {
if (ib_log_get_level(ib) >= 7) {
char* tmp_c = malloc(subject_len+1);
memcpy(tmp_c, subject, subject_len);
tmp_c[subject_len] = '\0';
/* No match. Return false to the caller (*result = 0). */
ib_log_debug2_tx(tx, "No match for [%s] using pattern [%s].",
tmp_c,
rule_data->patt);
free(tmp_c);
}
ib_rc = IB_OK;
*result = 0;
}
else {
/* Some other error occurred. Set the status to false and
report the error. */
ib_rc = IB_EUNKNOWN;
*result = 0;
}
free(ovector);
IB_FTRACE_RET_STATUS(ib_rc);
}
/**
* @brief Execute the dfa operator
*
* @param[in] tx Current transaction.
* @param[in] instance_data Instance data needed for execution.
* @param[in] field The field to operate on.
* @param[in] capture If non-NULL, the collection to capture to.
* @param[out] result The result of the operator 1=true 0=false.
* @param[in] cbdata Callback data.
*
* @returns IB_OK most times. IB_EALLOC when a memory allocation error handles.
*/
static
ib_status_t dfa_operator_execute(
ib_tx_t *tx,
void *instance_data,
const ib_field_t *field,
ib_field_t *capture,
ib_num_t *result,
void *cbdata
)
{
assert(instance_data != NULL);
assert(tx != NULL);
int matches;
ib_status_t ib_rc;
const int ovecsize = 3 * MATCH_MAX;
modpcre_operator_data_t *operator_data =
(modpcre_operator_data_t *)instance_data;
int *ovector;
const char *subject;
size_t subject_len;
const ib_bytestr_t *bytestr;
dfa_workspace_t *dfa_workspace;
const char *id = operator_data->id;
int options; /* dfa exec options. */
int start_offset;
int match_count;
const ib_module_t *m = (const ib_module_t *)cbdata;
assert(m != NULL);
assert(operator_data->cpdata->is_dfa == true);
ovector = (int *)malloc(ovecsize*sizeof(*ovector));
if (ovector==NULL) {
return IB_EALLOC;
}
if (field->type == IB_FTYPE_NULSTR) {
ib_rc = ib_field_value(field, ib_ftype_nulstr_out(&subject));
if (ib_rc != IB_OK) {
free(ovector);
return ib_rc;
}
subject_len = strlen(subject);
}
else if (field->type == IB_FTYPE_BYTESTR) {
ib_rc = ib_field_value(field, ib_ftype_bytestr_out(&bytestr));
if (ib_rc != IB_OK) {
free(ovector);
return ib_rc;
}
subject_len = ib_bytestr_length(bytestr);
subject = (const char *) ib_bytestr_const_ptr(bytestr);
}
else {
free(ovector);
return IB_EINVAL;
}
/* Get the per-tx workspace data for this rule data id. */
ib_rc = get_dfa_tx_data(m, tx, id, &dfa_workspace);
if (ib_rc == IB_ENOENT) {
/* First time we are called, clear the captures. */
if (capture) {
ib_rc = ib_capture_clear(capture);
if (ib_rc != IB_OK) {
ib_log_error_tx(tx, "Error clearing captures: %s",
ib_status_to_string(ib_rc));
}
}
options = PCRE_PARTIAL_SOFT;
ib_rc = alloc_dfa_tx_data(m, tx, operator_data->cpdata, id, &dfa_workspace);
if (ib_rc != IB_OK) {
free(ovector);
return ib_rc;
}
}
else if (ib_rc == IB_OK) {
options = PCRE_PARTIAL_SOFT | PCRE_DFA_RESTART;
}
else {
free(ovector);
return ib_rc;
}
/* Perform the match.
* If capturing is specified, then find all matches.
*/
start_offset = 0;
match_count = 0;
do {
matches = pcre_dfa_exec(operator_data->cpdata->cpatt,
operator_data->cpdata->edata,
subject,
subject_len,
start_offset, /* Starting offset. */
options,
ovector,
ovecsize,
dfa_workspace->workspace,
dfa_workspace->wscount);
if (matches > 0) {
++match_count;
/* Use the longest match - the first in ovector -
* to set the offset in the subject for the next
* match.
*/
start_offset = ovector[1] + 1;
if (capture) {
pcre_dfa_set_match(tx, capture, ovector, 1, subject);
}
}
} while (capture && (matches > 0));
if (match_count > 0) {
ib_rc = IB_OK;
*result = 1;
}
else if ((matches == 0) || (matches == PCRE_ERROR_NOMATCH)) {
ib_rc = IB_OK;
*result = 0;
}
else if (matches == PCRE_ERROR_PARTIAL) {
ib_rc = IB_OK;
*result = 0;
}
else {
/* Some other error occurred. Set the status to false and
* return the error. */
ib_rc = IB_EUNKNOWN;
*result = 0;
}
free(ovector);
return ib_rc;
}