parse.c

DHCP服务器源码

			    parse_warn (cfile, "more than one secondary.");
			skip_to_semi (cfile);
			return 0;
		    }
		    if (!option_cache_allocate (&zone -> secondary, MDL))
			    log_fatal ("can't allocate secondary.");
		    oc = zone -> secondary;
		  consemup:
		    token = next_token (&val, (unsigned *)0, cfile);
		    do {
			    struct expression *expr = (struct expression *)0;
			    if (!parse_ip_addr_or_hostname (&expr, cfile, 0)) {
				parse_warn (cfile,
					    "expecting IP addr or hostname.");
				skip_to_semi (cfile);
				return 0;
			    }
			    if (oc -> expression) {
				    struct expression *old =
					    (struct expression *)0;
				    expression_reference (&old,
							  oc -> expression,
							  MDL);
				    expression_dereference (&oc -> expression,
							    MDL);
				    if (!make_concat (&oc -> expression,
						      old, expr))
					log_fatal ("no memory for concat.");
				    expression_dereference (&expr, MDL);
				    expression_dereference (&old, MDL);
			    } else {
				    expression_reference (&oc -> expression,
							  expr, MDL);
				    expression_dereference (&expr, MDL);
			    }
			    token = next_token (&val, (unsigned *)0, cfile);
		    } while (token == COMMA);
		    if (token != SEMI) {
			    parse_warn (cfile, "expecting semicolon.");
			    skip_to_semi (cfile);
			    return 0;
		    }
		    break;

		  case KEY:
		    token = next_token (&val, (unsigned *)0, cfile);
		    token = peek_token (&val, (unsigned *)0, cfile);
		    if (token == STRING) {
			    token = next_token (&val, (unsigned *)0, cfile);
			    key_name = (char *)0;
		    } else {
			    key_name = parse_host_name (cfile);
			    if (!key_name) {
				    parse_warn (cfile, "expecting key name.");
				    skip_to_semi (cfile);
				    return 0;
			    }
			    val = key_name;
		    }
		    if (omapi_auth_key_lookup_name (&zone -> key, val) !=
			ISC_R_SUCCESS)
			    parse_warn (cfile, "unknown key %s", val);
		    if (key_name)
			    dfree (key_name, MDL);
		    if (!parse_semi (cfile))
			    return 0;
		    break;
		    
		  default:
		    done = 1;
		    break;
	    }
	} while (!done);

	token = next_token (&val, (unsigned *)0, cfile);
	if (token != RBRACE) {
		parse_warn (cfile, "expecting right brace.");
		return 0;
	}
	return 1;
}

/* key-statements :== key-statement |
		      key-statement key-statements
   key-statement :==
	ALGORITHM host-name SEMI |
	secret-definition SEMI
   secret-definition :== SECRET base64val |
			 SECRET STRING */

int parse_key (struct parse *cfile)
{
	int token;
	const char *val;
	int done = 0;
	struct auth_key *key;
	struct data_string ds;
	isc_result_t status;
	char *s;

	key = (struct auth_key *)0;
	if (omapi_auth_key_new (&key, MDL) != ISC_R_SUCCESS)
		log_fatal ("no memory for key");

	token = peek_token (&val, (unsigned *)0, cfile);
	if (token == STRING) {
		token = next_token (&val, (unsigned *)0, cfile);
		key -> name = dmalloc (strlen (val) + 1, MDL);
		if (!key -> name)
			log_fatal ("no memory for key name.");
		strcpy (key -> name, val);

	} else {
		key -> name = parse_host_name (cfile);
		if (!key -> name) {
			parse_warn (cfile, "expecting key name.");
			skip_to_semi (cfile);
			goto bad;
		}
	}

	token = next_token (&val, (unsigned *)0, cfile);
	if (token != LBRACE) {
		parse_warn (cfile, "expecting left brace");
		goto bad;
	}

	do {
		token = next_token (&val, (unsigned *)0, cfile);
		switch (token) {
		      case ALGORITHM:
			if (key -> algorithm) {
				parse_warn (cfile,
					    "key %s: too many algorithms",
					    key -> name);
				goto rbad;
			}
			key -> algorithm = parse_host_name (cfile);
			if (!key -> algorithm) {
				parse_warn (cfile,
					    "expecting key algorithm name.");
				goto rbad;
			}
			if (!parse_semi (cfile))
				goto rbad;
			/* If the algorithm name isn't an FQDN, tack on
			   the .SIG-ALG.REG.NET. domain. */
			s = strrchr (key -> algorithm, '.');
			if (!s) {
			    static char add [] = ".SIG-ALG.REG.INT.";
			    s = dmalloc (strlen (key -> algorithm) +
					 sizeof (add), MDL);
			    if (!s) {
				log_error ("no memory for key %s.",
					   "algorithm");
				goto rbad;
			    }
			    strcpy (s, key -> algorithm);
			    strcat (s, add);
			    dfree (key -> algorithm, MDL);
			    key -> algorithm = s;
			} else if (s [1]) {
			    /* If there is no trailing '.', hack one in. */
			    s = dmalloc (strlen (key -> algorithm) + 2, MDL);
			    if (!s) {
				    log_error ("no memory for key %s.",
					       key -> algorithm);
				    goto rbad;
			    }
			    strcpy (s, key -> algorithm);
			    strcat (s, ".");
			    dfree (key -> algorithm, MDL);
			    key -> algorithm = s;
			}
			break;

		      case SECRET:
			if (key -> key) {
				parse_warn (cfile, "key %s: too many secrets",
					    key -> name);
				goto rbad;
			}

			memset (&ds, 0, sizeof(ds));
			if (!parse_base64 (&ds, cfile))
				goto rbad;
			status = omapi_data_string_new (&key -> key, ds.len,
							MDL);
			if (status != ISC_R_SUCCESS)
				goto rbad;
			memcpy (key -> key -> value,
				ds.buffer -> data, ds.len);
			data_string_forget (&ds, MDL);

			if (!parse_semi (cfile))
				goto rbad;
			break;

		      default:
			done = 1;
			break;
		}
	} while (!done);
	if (token != RBRACE) {
		parse_warn (cfile, "expecting right brace.");
		goto rbad;
	}
	/* Allow the BIND 8 syntax, which has a semicolon after each
	   closing brace. */
	token = peek_token (&val, (unsigned *)0, cfile);
	if (token == SEMI)
		token = next_token (&val, (unsigned *)0, cfile);

	/* Remember the key. */
	status = omapi_auth_key_enter (key);
	if (status != ISC_R_SUCCESS) {
		parse_warn (cfile, "tsig key %s: %s",
			    key -> name, isc_result_totext (status));
		goto bad;
	}
	omapi_auth_key_dereference (&key, MDL);
	return 1;

      rbad:
	skip_to_rbrace (cfile, 1);
      bad:
	omapi_auth_key_dereference (&key, MDL);
	return 0;
}

/*
 * on-statement :== event-types LBRACE executable-statements RBRACE
 * event-types :== event-type OR event-types |
 *		   event-type
 * event-type :== EXPIRY | COMMIT | RELEASE
 */

int parse_on_statement (result, cfile, lose)
	struct executable_statement **result;
	struct parse *cfile;
	int *lose;
{
	enum dhcp_token token;
	const char *val;

	if (!executable_statement_allocate (result, MDL))
		log_fatal ("no memory for new statement.");
	(*result) -> op = on_statement;

	do {
		token = next_token (&val, (unsigned *)0, cfile);
		switch (token) {
		      case EXPIRY:
			(*result) -> data.on.evtypes |= ON_EXPIRY;
			break;
		
		      case COMMIT:
			(*result) -> data.on.evtypes |= ON_COMMIT;
			break;
			
		      case RELEASE:
			(*result) -> data.on.evtypes |= ON_RELEASE;
			break;
			
		      case TRANSMISSION:
			(*result) -> data.on.evtypes |= ON_TRANSMISSION;
			break;

		      default:
			parse_warn (cfile, "expecting a lease event type");
			skip_to_semi (cfile);
			*lose = 1;
			executable_statement_dereference (result, MDL);
			return 0;
		}
		token = next_token (&val, (unsigned *)0, cfile);
	} while (token == OR);
		
	/* Semicolon means no statements. */
	if (token == SEMI)
		return 1;

	if (token != LBRACE) {
		parse_warn (cfile, "left brace expected.");
		skip_to_semi (cfile);
		*lose = 1;
		executable_statement_dereference (result, MDL);
		return 0;
	}
	if (!parse_executable_statements (&(*result) -> data.on.statements,
					  cfile, lose, context_any)) {
		if (*lose) {
			/* Try to even things up. */
			do {
				token = next_token (&val,
						    (unsigned *)0, cfile);
			} while (token != END_OF_FILE && token != RBRACE);
			executable_statement_dereference (result, MDL);
			return 0;
		}
	}
	token = next_token (&val, (unsigned *)0, cfile);
	if (token != RBRACE) {
		parse_warn (cfile, "right brace expected.");
		skip_to_semi (cfile);
		*lose = 1;
		executable_statement_dereference (result, MDL);
		return 0;
	}
	return 1;
}

/*
 * switch-statement :== LPAREN expr RPAREN LBRACE executable-statements RBRACE
 *
 */

int parse_switch_statement (result, cfile, lose)
	struct executable_statement **result;
	struct parse *cfile;
	int *lose;
{
	enum dhcp_token token;
	const char *val;

	if (!executable_statement_allocate (result, MDL))
		log_fatal ("no memory for new statement.");
	(*result) -> op = switch_statement;

	token = next_token (&val, (unsigned *)0, cfile);
	if (token != LPAREN) {
		parse_warn (cfile, "expecting left brace.");
	      pfui:
		*lose = 1;
		skip_to_semi (cfile);
	      gnorf:
		executable_statement_dereference (result, MDL);
		return 0;
	}

	if (!parse_expression (&(*result) -> data.s_switch.expr,
			       cfile, lose, context_data_or_numeric,
			       (struct expression **)0, expr_none)) {
		if (!*lose) {
			parse_warn (cfile,
				    "expecting data or numeric expression.");
			goto pfui;
		}
		goto gnorf;
	}

	token = next_token (&val, (unsigned *)0, cfile);
	if (token != RPAREN) {
		parse_warn (cfile, "right paren expected.");
		goto pfui;
	}

	token = next_token (&val, (unsigned *)0, cfile);
	if (token != LBRACE) {
		parse_warn (cfile, "left brace expected.");
		goto pfui;
	}
	if (!(parse_executable_statements
	      (&(*result) -> data.s_switch.statements, cfile, lose,
	       (is_data_expression ((*result) -> data.s_switch.expr)
		? context_data : context_numeric)))) {
		if (*lose) {
			skip_to_rbrace (cfile, 1);
			executable_statement_dereference (result, MDL);
			return 0;
		}
	}
	token = next_token (&val, (unsigned *)0, cfile);
	if (token != RBRACE) {
		parse_warn (cfile, "right brace expected.");
		goto pfui;
	}
	return 1;
}

/*
 * case-statement :== CASE expr COLON
 *
 */

int parse_case_statement (result, cfile, lose, case_context)
	struct executable_statement **result;
	struct parse *cfile;
	int *lose;
	enum expression_context case_context;
{
	enum dhcp_token token;
	const char *val;

	if (!executable_statement_allocate (result, MDL))
		log_fatal ("no memory for new statement.");
	(*result) -> op = case_statement;

	if (!parse_expression (&(*result) -> data.c_case,
			       cfile, lose, case_context,
			       (struct expression **)0, expr_none))
	{
		if (!*lose) {
			parse_warn (cfile, "expecting %s expression.",
				    (case_context == context_data
				     ? "data" : "numeric"));
		}
	      pfui:
		*lose = 1;
		skip_to_semi (cfile);
		executable_statement_dereference (result, MDL);
		return 0;
	}

	token = next_token (&val, (unsigned *)0, cfile);
	if (token != COLON) {
		parse_warn (cfile, "colon expected.");
		goto pfui;
	}
	return 1;
}

/*
 * if-statement :== boolean-expression LBRACE executable-statements RBRACE
 *						else-statement
 *
 * else-statement :== <null> |
 *		      ELSE LBRACE executable-statements RBRACE |
 *		      ELSE IF if-statement |
 *		      ELSIF if-statement
 */

int parse_if_statement (result, cfile, lose)
	struct executable_statement **result;
	struct parse *cfile;
	int *lose;
{
	enum dhcp_token token;
	const char *val;
	int parenp;

	if (!executable_statement_allocate (result, MDL))
		log_fatal ("no memory for if statement.");

	(*result) -> op = if_statement;

	token = peek_token (&val, (unsigned *)0, cfile);
	if (token == LPAREN) {
		parenp = 1;
		next_token (&val, (unsigned *)0, cfile);
	} else
		parenp = 0;


	if (!parse_boolean_expression (&(*result) -> data.ie.expr,
				       cfile, lose)) {
		if (!*lose)
			parse_warn (cfile, "boolean expression expected.");
		executable_statement_dereference (result, MDL);
		*lose = 1;
		return 0;
	}
#if defined (DEBUG_EXPRESSION_PARSE)
	print_expression ("if condition", (*result) -> data.ie.expr);
#endif
	if (parenp) {
		token = next_token (&val, (unsigned *)0, cfile);
		if (token != RPAREN) {
			parse_warn (cfile, "expecting right paren.");
			*lose = 1;
			executable_statement_dereference (result, MDL);
			return 0;
		}
	}
	token = next_token (&val, (unsigned *)0, cfile);
	if (token != LBRACE) {
		parse_warn (cfile, "left brace expected.");
		skip_to_semi (cfile);
		*lose = 1;
		executable_statement_dereference (result, MDL);
		return 0;
	}
	if (!parse_executable_statements (&(*result) -> data.ie.tc,
					  cfile, lose, context_any)) {
		if (*lose) {
			/* Try to even things up. */
			do {
				token = next_token (&val,
						    (unsigned *)0, cfile);
			} while (token != END_OF_FILE && token != RBRACE);
			executable_statement_dereference (result, MDL);
			return 0;
		}
	}
	token = next_token (&val, (unsigned *)0, cfile);
	if (token != RBRACE) {
		parse_warn (cfile, "right brace expected.");
		skip_to_semi (cfile);
		*lose = 1;
		executable_statement_dereference (result, MDL);
		return 0;
	}
	token = peek_token (&val, (unsigned *)0, cfile);
	if (token == ELSE) {
		token = next_token (&val, (unsigned *)0, cfile);
		token = peek_token (&val, (unsigned *)0, cfile);
		if (token == IF) {
			token = next_token (&val, (unsigned *)0, cfile);
			if (!parse_if_statement (&(*result) -> data.ie.fc,
						 cfile, lose)) {
				if (!*lose)
					parse_warn (cfile,
						    "expecting if statement");
				executable_statement_dereference (result, MDL);
				*lose = 1;
				return 0;
			}
		} else if (token != LBRACE) {
			parse_warn (cfile, "left brac