evaluate.c

使用最广泛的radius的linux的源码

			 *	instead take an operator, a pointer to
			 *	the comparison result, and return
			 *	"true/false" for "comparions
			 *	succeeded/failed", which are different
			 *	error codes than "comparison is less
			 *	than, equal to, or greater than zero".
			 */
			compare = radius_callback_compare(state->request,
							  vp, myvp, NULL, NULL);
			pairfree(&myvp);

		} else {
			/*
			 *	FIXME: Do something for RHS type?
			 */
			fr_printf_log("CMP %s %s\n", lhs_buffer, this->rhs);
			compare = strcmp(lhs_buffer, this->rhs);
		}

		debug_evaluate("CONDITION COMPARE %d\n", compare);

		switch (this->compare) {
		case POLICY_LEX_CMP_EQUALS:
			rcode = (compare == 0);
			break;

		case POLICY_LEX_CMP_NOT_EQUALS:
			rcode = (compare != 0);
			break;

		case POLICY_LEX_LT:
			rcode = (compare < 0);
			break;

		case POLICY_LEX_GT:
			rcode = (compare > 0);
			break;

		case POLICY_LEX_LE:
			rcode =(compare <= 0);
			break;

		case POLICY_LEX_GE:
			rcode = (compare >= 0);
			break;

#ifdef HAVE_REGEX_H
		case POLICY_LEX_RX_EQUALS:
		{ /* FIXME: copied from src/main/valuepair.c */
			int i;
			regmatch_t rxmatch[REQUEST_MAX_REGEX + 1];

			/*
			 *	Include substring matches.
			 */
			if (regcomp(&reg, this->rhs,
				    REG_EXTENDED) != 0) {
				/* FIXME: print error */
				return FALSE;
			}
			rad_assert(data != NULL);
			rcode = regexec(&reg, data,
					REQUEST_MAX_REGEX + 1,
					rxmatch, 0);
			rcode = (rcode == 0);
			regfree(&reg);

			/*
			 *	Add %{0}, %{1}, etc.
			 */
			for (i = 0; i <= REQUEST_MAX_REGEX; i++) {
				char *p;
				char rxbuffer[256];

				/*
				 *	Didn't match: delete old
				 *	match, if it existed.
				 */
				if (!rcode ||
				    (rxmatch[i].rm_so == -1)) {
					p = request_data_get(state->request, state->request,
							     REQUEST_DATA_REGEX | i);
					if (p) {
						free(p);
						continue;
					}

					/*
					 *	No previous match
					 *	to delete, stop.
					 */
					break;
				}

				/*
				 *	Copy substring into buffer.
				 */
				memcpy(rxbuffer,
				       data + rxmatch[i].rm_so,
				       rxmatch[i].rm_eo - rxmatch[i].rm_so);
				rxbuffer[rxmatch[i].rm_eo - rxmatch[i].rm_so] = '\0';

				/*
				 *	Copy substring, and add it to
				 *	the request.
				 *
				 *	Note that we don't check
				 *	for out of memory, which is
				 *	the only error we can get...
				 */
				p = strdup(rxbuffer);
				request_data_add(state->request,
						 state->request,
						 REQUEST_DATA_REGEX | i,
						 p, free);
			}

		}
		break;

		case POLICY_LEX_RX_NOT_EQUALS:
			regcomp(&reg, this->rhs, REG_EXTENDED|REG_NOSUB);
			rad_assert(data != NULL);
			rcode = regexec(&reg, data,
					0, NULL, 0);
			rcode = (rcode != 0);
			regfree(&reg);
				break;
#endif /* HAVE_REGEX_H */
		default:
			rcode = FALSE;
			break;
		} /* switch over comparison operators */
		break;		/* default from first switch over compare */
	}

	if (this->sense) rcode = (rcode == FALSE); /* reverse sense of test */

	/*
	 *	No trailing &&, ||
	 */
	switch (this->child_condition) {
	default:
		return rcode;

	case POLICY_LEX_L_AND:
		if (!rcode) return rcode; /* FALSE && x == FALSE */
		break;

	case POLICY_LEX_L_OR:
		if (rcode) return rcode; /* TRUE && x == TRUE */
		break;
	}

	/*
	 *	Tail recursion.
	 */
	this = (const policy_condition_t *) this->child;
	goto redo;

	return 1;		/* should never reach here */
}


/*
 *	Evaluate an 'if' statement
 */
static int evaluate_if(policy_state_t *state, const policy_item_t *item)
{
	int rcode;
	const policy_if_t *this;

	this = (const policy_if_t *) item;

	/*
	 *	evaluate_condition calls itself recursively.
	 *	We should probably allocate a new state, instead.
	 */
	rcode = evaluate_condition(state, this->condition);
	debug_evaluate("IF condition returned %s\n",
	       rcode ? "true" : "false");
	if (rcode) {
		rcode = policy_stack_push(state, this->if_true);
		if (!rcode) return rcode;
	} else if (this->if_false) {
		rcode = policy_stack_push(state, this->if_false);
		if (!rcode) return rcode;
	}

	/*
	 *	'if' can fail, if the block it's processing fails.
	 */
	return 1;;
}


/*
 *	Make a VALUE_PAIR from a policy_assignment_t*
 *
 *	The assignment operator has to be '='.
 */
static VALUE_PAIR *assign2vp(REQUEST *request,
			     const policy_assignment_t *assign)
{
	VALUE_PAIR *vp;
	FR_TOKEN operator = T_OP_EQ;
	const char *value = assign->rhs;
	char buffer[2048];

	if ((assign->rhs_type == POLICY_LEX_DOUBLE_QUOTED_STRING) &&
	    (strchr(assign->rhs, '%') != NULL)) {
		radius_xlat(buffer, sizeof(buffer), assign->rhs,
			    request, NULL);
		value = buffer;
	}

	/*
	 *	This is crappy.. fix it.
	 */
	switch (assign->assign) {
	case POLICY_LEX_ASSIGN:
		operator = T_OP_EQ;
		break;

	case POLICY_LEX_SET_EQUALS:
		operator = T_OP_SET;
		break;

	case POLICY_LEX_PLUS_EQUALS:
		operator = T_OP_ADD;
		break;

	default:
		fprintf(stderr, "Expected '=' for operator, not '%s' at line %d\n",
			fr_int2str(rlm_policy_tokens,
				     assign->assign, "?"),
			assign->item.lineno);
		return NULL;
	}

	vp = pairmake(assign->lhs, value, operator);
	if (!vp) {
		fprintf(stderr, "Failed creating pair: %s %s\n", value, librad_errstr);
	}

	return vp;
}


/*
 *	Evaluate a 'packet .= {attrs}' statement
 */
static int evaluate_attr_list(policy_state_t *state, const policy_item_t *item)
{
	const policy_attributes_t *this;
	VALUE_PAIR **vps = NULL;
	VALUE_PAIR *vp, *head, **tail;
	const policy_item_t *attr;
	policy_lex_t this_how;

	this = (const policy_attributes_t *) item;

	switch (this->where) {
	case POLICY_RESERVED_CONTROL:
		vps = &(state->request->config_items);
		break;

	case POLICY_RESERVED_REQUEST:
		vps = &(state->request->packet->vps);
		break;

	case POLICY_RESERVED_REPLY:
		vps = &(state->request->reply->vps);
		break;

	case POLICY_RESERVED_PROXY_REQUEST:
		if (!state->request->proxy) return 0; /* FIXME: print error */
		vps = &(state->request->proxy->vps);
		break;

	case POLICY_RESERVED_PROXY_REPLY:
		if (!state->request->proxy_reply) return 0; /* FIXME: print error */
		vps = &(state->request->proxy_reply->vps);
		break;

	default:
		return 0;
	}

	head = NULL;
	tail = &head;

	for (attr = this->attributes; attr != NULL; attr = attr->next) {
		if (attr->type != POLICY_TYPE_ASSIGNMENT) {
			fprintf(stderr, "bad assignment in attribute list at line %d\n", attr->lineno);
			pairfree(&head);
			return 0;
		}

		vp = assign2vp(state->request, (const policy_assignment_t *) attr);
		if (!vp) {
			fprintf(stderr, "Failed to allocate VP\n");
			pairfree(&head);
			return 0;
		}
		*tail = vp;
		tail = &(vp->next);
	}

	this_how = this->how;
 retry_how:
	switch (this_how) {
	case POLICY_LEX_SET_EQUALS: /* dangerous: removes all previous things! */
		pairfree(vps);
		*vps = head;
		break;

	case POLICY_LEX_AFTER_TAIL_ASSIGN:
		pairmove(vps, &head);
		pairfree(&head);
		break;

	case POLICY_LEX_ASSIGN: /* 'union' */
		pairmove(vps, &head);
		pairfree(&head);
		break;

	case POLICY_LEX_BEFORE_HEAD_ASSIGN:
		pairmove(&head, vps);
		pairfree(vps);
		*vps = head;
		break;

	case POLICY_LEX_AFTER_TAIL_EQUALS:
	case POLICY_LEX_CONCAT_EQUALS:
		pairadd(vps, head);
		break;

	case POLICY_LEX_BEFORE_HEAD_EQUALS:
		pairadd(&head, *vps);
		*vps = head;
		break;

	case POLICY_LEX_BEFORE_WHERE_EQUALS:
	case POLICY_LEX_AFTER_WHERE_EQUALS:
	case POLICY_LEX_BEFORE_WHERE_ASSIGN:
	case POLICY_LEX_AFTER_WHERE_ASSIGN:
		/* find location*/
		{
			VALUE_PAIR *vpprev = NULL, *vpnext = NULL, *lvp;

			for(lvp = *vps; lvp; vpprev = lvp, lvp = lvp->next) {
				vpnext = lvp->next;
				lvp->next = NULL;
				if (evaluate_condition(state, this->where_loc))
					break;
				lvp->next = vpnext;
			}

			if (lvp) { 
				switch(this_how) {
				case POLICY_LEX_BEFORE_WHERE_EQUALS:
				case POLICY_LEX_BEFORE_WHERE_ASSIGN:
					if (vpprev) {
						lvp->next = vpnext;
						vpnext = lvp;
						vpprev->next = NULL;
						lvp = vpprev;
					}
				default: /* always reached */
					break;
				}

				switch(this_how) {
				case POLICY_LEX_BEFORE_WHERE_EQUALS:
					if (vpprev) 
						pairadd(&lvp, head);
					else
						*vps = lvp = head;
					break;
 				case POLICY_LEX_AFTER_WHERE_EQUALS:
 					pairadd(&lvp, head);
					break;
				case POLICY_LEX_BEFORE_WHERE_ASSIGN:
					if (vpprev) {
						pairmove(&lvp, &head);
						pairfree(&head);
					}
					else
						*vps = lvp = head;
					break;
				case POLICY_LEX_AFTER_WHERE_ASSIGN:
					pairmove(&lvp, &head);
					pairfree(&head);
					break;
				default:/*never reached*/
					break;
				}	
				for( ; lvp && lvp->next; lvp = lvp->next);
				if (lvp)
					lvp->next = vpnext;
				break;
			}

			switch(this_how) {
				case POLICY_LEX_BEFORE_WHERE_EQUALS:
					this_how = POLICY_LEX_BEFORE_HEAD_EQUALS;
					break;
				case POLICY_LEX_AFTER_WHERE_EQUALS:
					this_how = POLICY_LEX_AFTER_TAIL_EQUALS;
					break;
				case POLICY_LEX_BEFORE_WHERE_ASSIGN:
					this_how = POLICY_LEX_BEFORE_HEAD_ASSIGN;
					break;
				case POLICY_LEX_AFTER_WHERE_ASSIGN:
					this_how = POLICY_LEX_AFTER_TAIL_ASSIGN;
					break;
				default: /*never reached*/
					break;
			}
			goto retry_how; 
		}
		/* FALL-THROUGH */

	default:
		fprintf(stderr, "HUH?\n");
		pairfree(&head);
		return 0;
	}

	state->rcode = RLM_MODULE_UPDATED; /* we did stuff */

	return 1;
}


/*
 *	Evaluate a reference call to a module.
 */
static int evaluate_call(policy_state_t *state, const policy_item_t *item)
{
	int rcode;
	const policy_call_t *this;
	const policy_named_t *policy;

	this = (const policy_call_t *) item;

	policy = rlm_policy_find(state->inst->policies, this->name);
	if (!policy) return 0;	/* not found... */

	DEBUG2("rlm_policy: Evaluating policy %s", this->name);

	rad_assert(policy->policy->type != POLICY_TYPE_BAD);
	rad_assert(policy->policy->type < POLICY_TYPE_NUM_TYPES);

	/*
	 *	Push the name of the function onto the stack,
	 *	so that we can catch recursive calls.
	 *
	 *	The "pop" function will skip over it when it sees it.
	 */
	rcode = policy_stack_push(state, (const policy_item_t *) policy);
	if (!rcode) {
		return rcode;
	}

	/*
	 *	Push it onto the stack.  Other code will take care of
	 *	calling it.
	 */
	rcode = policy_stack_push(state, policy->policy);
	if (!rcode) {
		return rcode;
	}

	return 1;
}


/*
 *	Evaluate a return statement
 */
static int evaluate_return(policy_state_t *state, const policy_item_t *item)
{
	const policy_return_t *this;

	this = (const policy_return_t *) item;
	state->rcode = this->rcode;

	return 1;		/* we succeeded */
}


/*
 *	Evaluate a module statement
 */
static int evaluate_module(policy_state_t *state, const policy_item_t *item)
{
	const policy_module_t *this;

	this = (const policy_module_t *) item;

	/*
	 *	Just to be paranoid.  Maybe we want to loosen this
	 *	restriction in the future?
	 */
	if (this->component != state->component) {
		DEBUG2("rlm_policy: Cannot mix & match components");
		return 0;
	}

	DEBUG2("rlm_policy: begin nested call");
	state->rcode = modcall(this->component, this->mc, state->request);
	DEBUG2("rlm_policy: end nested call");

	return 1;		/* we succeeded */
}


/*
 *	State machine stuff.
 */
typedef int (*policy_evaluate_type_t)(policy_state_t *, const policy_item_t *);


/*
 *	MUST be kept in sync with policy_type_t
 */
static policy_evaluate_type_t evaluate_functions[POLICY_TYPE_NUM_TYPES] = {
	NULL,			/* POLICY_TYPE_BAD */
	evaluate_if,
	evaluate_condition,
	evaluate_assignment,
	evaluate_attr_list,
	evaluate_print,
	NULL,			/* define a named policy.. */
	evaluate_call,
	evaluate_return,
	evaluate_module
};


/*
 *	Evaluate a policy, keyed by name.
 */
static int policy_evaluate_name(policy_state_t *state, const char *name)
{
	int rcode;
	const policy_item_t *this;
	policy_named_t mypolicy, *policy;

	mypolicy.name = name;
	policy = rbtree_finddata(state->inst->policies, &mypolicy);
	if (!policy) return RLM_MODULE_FAIL;

	DEBUG2("rlm_policy: Evaluating policy %s", name);

	rad_assert(policy->item.type != POLICY_TYPE_BAD);
	rad_assert(policy->item.type < POLICY_TYPE_NUM_TYPES);

	rcode = policy_stack_push(state, policy->policy);
	if (!rcode) {
		return RLM_MODULE_FAIL;
	}

	/*
	 *	FIXME: Look for magic keywords like "return",
	 *	where the packet gets accepted/rejected/whatever
	 */
	while (policy_stack_pop(state, &this)) {
		rad_assert(this != NULL);
		rad_assert(this->type != POLICY_TYPE_BAD);
		rad_assert(this->type < POLICY_TYPE_NUM_TYPES);

		debug_evaluate("Evaluating at line %d\n",
			       this->lineno);
		rcode = (*evaluate_functions[this->type])(state,
							  this);
		if (!rcode) {
			return RLM_MODULE_FAIL;
		}
	} /* loop until the stack is empty */

	return state->rcode;
}


/*
 *	Evaluate, which is pretty close to print, but we look at what
 *	we're printing.
 */
int rlm_policy_evaluate(rlm_policy_t *inst, REQUEST *request, const char *name)
{
	int rcode;
	policy_state_t *state;

	state = rad_malloc(sizeof(*state));
	memset(state, 0, sizeof(*state));
	state->request = request;
	state->inst = inst;
	state->rcode = RLM_MODULE_OK;
	state->component = fr_str2int(policy_component_names, name,
					RLM_COMPONENT_COUNT);

	rcode = policy_evaluate_name(state, name);

	free(state);

	return rcode;		/* evaluated OK. */
}