view src/config/config-parser.c @ 21322:5ab8dc1a4a6f

global: Change string position/length from unsigned int to size_t Mainly to avoid truncating >4GB strings, which might potentially cause some security holes. Normally there are other limits, which prevent such excessive strings from being created in the first place. I'm sure this didn't find everything. Maybe everything could be found with compiler warnings. -Wconversion kind of does it, but it gives way too many unnecessary warnings. These were mainly found with: grep " = strlen" egrep "unsigned int.*(size|len)"
author Timo Sirainen <timo.sirainen@dovecot.fi>
date Mon, 12 Dec 2016 07:19:55 +0200
parents 5bcd6014d598
children f482a60bc73a
line wrap: on
line source

/* Copyright (c) 2005-2016 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "array.h"
#include "str.h"
#include "hash.h"
#include "strescape.h"
#include "istream.h"
#include "module-dir.h"
#include "settings-parser.h"
#include "service-settings.h"
#include "master-service.h"
#include "master-service-settings.h"
#include "master-service-ssl-settings.h"
#include "all-settings.h"
#include "old-set-parser.h"
#include "config-request.h"
#include "config-parser-private.h"

#include <unistd.h>
#include <fcntl.h>
#include <time.h>
#ifdef HAVE_GLOB_H
#  include <glob.h>
#endif

#ifndef GLOB_BRACE
#  define GLOB_BRACE 0
#endif

#define DNS_LOOKUP_TIMEOUT_SECS 30
#define DNS_LOOKUP_WARN_SECS 5

ARRAY_DEFINE_TYPE(setting_parser_info_p, const struct setting_parser_info *);

static const enum settings_parser_flags settings_parser_flags =
	SETTINGS_PARSER_FLAG_IGNORE_UNKNOWN_KEYS |
	SETTINGS_PARSER_FLAG_TRACK_CHANGES;

struct config_module_parser *config_module_parsers;
struct config_filter_context *config_filter;
struct module *modules;
void (*hook_config_parser_begin)(struct config_parser_context *ctx);
int (*hook_config_parser_end)(struct config_parser_context *ctx,
			      const char **error_r);

static ARRAY_TYPE(service_settings) services_free_at_deinit = ARRAY_INIT;
static ARRAY_TYPE(setting_parser_info_p) roots_free_at_deinit = ARRAY_INIT;

static const char *info_type_name_find(const struct setting_parser_info *info)
{
	unsigned int i;

	for (i = 0; info->defines[i].key != NULL; i++) {
		if (info->defines[i].offset == info->type_offset)
			return info->defines[i].key;
	}
	i_panic("setting parser: Invalid type_offset value");
	return NULL;
}

static int config_add_type(struct setting_parser_context *parser,
			   const char *line, const char *section_name)
{
	const struct setting_parser_info *info;
	const char *p;
	string_t *str;
	int ret;

	info = settings_parse_get_prev_info(parser);
	if (info == NULL) {
		/* section inside strlist */
		return -1;
	}
	if (info->type_offset == (size_t)-1)
		return 0;

	str = t_str_new(256);
	p = strchr(line, '=');
	str_append_n(str, line, p-line);
	str_append_c(str, SETTINGS_SEPARATOR);
	str_append(str, p+1);
	if (info != NULL) {
		str_append_c(str, SETTINGS_SEPARATOR);
		str_append(str, info_type_name_find(info));
	}

	ret = settings_parse_keyvalue(parser, str_c(str), section_name);
	i_assert(ret > 0);
	return 0;
}

static bool
config_parser_is_in_localremote(struct config_section_stack *section)
{
	const struct config_filter *filter = &section->filter;

	return filter->local_name != NULL || filter->local_bits > 0 ||
		filter->remote_bits > 0;
}

int config_apply_line(struct config_parser_context *ctx, const char *key,
		      const char *line, const char *section_name)
{
	struct config_module_parser *l;
	bool found = FALSE;
	int ret;

	for (l = ctx->cur_section->parsers; l->root != NULL; l++) {
		ret = settings_parse_line(l->parser, line);
		if (ret > 0) {
			found = TRUE;
			/* FIXME: remove once auth does support these. */
			if (strcmp(l->root->module_name, "auth") == 0 &&
			    config_parser_is_in_localremote(ctx->cur_section)) {
				ctx->error = p_strconcat(ctx->pool,
					"Auth settings not supported inside local/remote blocks: ",
					key, NULL);
				return -1;
			}
			if (section_name != NULL) {
				if (config_add_type(l->parser, line, section_name) < 0) {
					ctx->error = "Section not allowed here";
					return -1;
				}
			}
		} else if (ret < 0) {
			ctx->error = settings_parser_get_error(l->parser);
			return -1;
		}
	}
	if (!found) {
		ctx->error = p_strconcat(ctx->pool, "Unknown setting: ",
					 key, NULL);
		return -1;
	}
	return 0;
}

static const char *
fix_relative_path(const char *path, struct input_stack *input)
{
	const char *p;

	if (*path == '/')
		return path;

	p = strrchr(input->path, '/');
	if (p == NULL)
		return path;

	return t_strconcat(t_strdup_until(input->path, p+1), path, NULL);
}

static struct config_module_parser *
config_module_parsers_init(pool_t pool)
{
	struct config_module_parser *dest;
	unsigned int i, count;

	for (count = 0; all_roots[count] != NULL; count++) ;

	dest = p_new(pool, struct config_module_parser, count + 1);
	for (i = 0; i < count; i++) {
		dest[i].root = all_roots[i];
		dest[i].parser = settings_parser_init(pool, all_roots[i],
						      settings_parser_flags);
	}
	return dest;
}

static void
config_add_new_parser(struct config_parser_context *ctx)
{
	struct config_section_stack *cur_section = ctx->cur_section;
	struct config_filter_parser *parser;

	parser = p_new(ctx->pool, struct config_filter_parser, 1);
	parser->filter = cur_section->filter;
	if (ctx->cur_input->linenum == 0) {
		parser->file_and_line =
			p_strdup(ctx->pool, ctx->cur_input->path);
	} else {
		parser->file_and_line =
			p_strdup_printf(ctx->pool, "%s:%d",
					ctx->cur_input->path,
					ctx->cur_input->linenum);
	}
	parser->parsers = cur_section->prev == NULL ? ctx->root_parsers :
		config_module_parsers_init(ctx->pool);
	array_append(&ctx->all_parsers, &parser, 1);

	cur_section->parsers = parser->parsers;
}

static struct config_section_stack *
config_add_new_section(struct config_parser_context *ctx)
{
	struct config_section_stack *section;

	section = p_new(ctx->pool, struct config_section_stack, 1);
	section->prev = ctx->cur_section;
	section->filter = ctx->cur_section->filter;
	section->parsers = ctx->cur_section->parsers;

	section->open_path = p_strdup(ctx->pool, ctx->cur_input->path);
	section->open_linenum = ctx->cur_input->linenum;
	return section;
}

static struct config_filter_parser *
config_filter_parser_find(struct config_parser_context *ctx,
			  const struct config_filter *filter)
{
	struct config_filter_parser *const *parsers;

	array_foreach(&ctx->all_parsers, parsers) {
		struct config_filter_parser *parser = *parsers;

		if (config_filters_equal(&parser->filter, filter))
			return parser;
	}
	return NULL;
}

int config_parse_net(const char *value, struct ip_addr *ip_r,
		     unsigned int *bits_r, const char **error_r)
{
	struct ip_addr *ips;
	const char *p;
	unsigned int ip_count, bits, max_bits;
	time_t t1, t2;
	int ret;

	if (net_parse_range(value, ip_r, bits_r) == 0)
		return 0;

	p = strchr(value, '/');
	if (p != NULL) {
		value = t_strdup_until(value, p);
		p++;
	}

	t1 = time(NULL);
	alarm(DNS_LOOKUP_TIMEOUT_SECS);
	ret = net_gethostbyname(value, &ips, &ip_count);
	alarm(0);
	t2 = time(NULL);
	if (ret != 0) {
		*error_r = t_strdup_printf("gethostbyname(%s) failed: %s",
					   value, net_gethosterror(ret));
		return -1;
	}
	*ip_r = ips[0];

	if (t2 - t1 >= DNS_LOOKUP_WARN_SECS) {
		i_warning("gethostbyname(%s) took %d seconds",
			  value, (int)(t2-t1));
	}

	max_bits = IPADDR_IS_V4(&ips[0]) ? 32 : 128;
	if (p == NULL)
		*bits_r = max_bits;
	else if (str_to_uint(p, &bits) == 0 && bits <= max_bits)
		*bits_r = bits;
	else {
		*error_r = t_strdup_printf("Invalid network mask: %s", p);
		return -1;
	}
	return 0;
}

static bool
config_filter_add_new_filter(struct config_parser_context *ctx,
			     const char *key, const char *value)
{
	struct config_filter *filter = &ctx->cur_section->filter;
	struct config_filter *parent = &ctx->cur_section->prev->filter;
	struct config_filter_parser *parser;
	const char *error;

	if (strcmp(key, "protocol") == 0) {
		if (parent->service != NULL)
			ctx->error = "Nested protocol { protocol { .. } } block not allowed";
		else
			filter->service = p_strdup(ctx->pool, value);
	} else if (strcmp(key, "local") == 0) {
		if (parent->remote_bits > 0)
			ctx->error = "remote { local { .. } } not allowed (use local { remote { .. } } instead)";
		else if (parent->service != NULL)
			ctx->error = "protocol { local { .. } } not allowed (use local { protocol { .. } } instead)";
		else if (parent->local_name != NULL)
			ctx->error = "local_name { local { .. } } not allowed (use local { local_name { .. } } instead)";
		else if (config_parse_net(value, &filter->local_net,
					  &filter->local_bits, &error) < 0)
			ctx->error = p_strdup(ctx->pool, error);
		else if (parent->local_bits > filter->local_bits ||
			 (parent->local_bits > 0 &&
			  !net_is_in_network(&filter->local_net,
					     &parent->local_net,
					     parent->local_bits)))
			ctx->error = "local net1 { local net2 { .. } } requires net2 to be inside net1";
		else
			filter->local_host = p_strdup(ctx->pool, value);
	} else if (strcmp(key, "local_name") == 0) {
		if (parent->remote_bits > 0)
			ctx->error = "remote { local_name { .. } } not allowed (use local_name { remote { .. } } instead)";
		else if (parent->service != NULL)
			ctx->error = "protocol { local_name { .. } } not allowed (use local_name { protocol { .. } } instead)";
		else
			filter->local_name = p_strdup(ctx->pool, value);
	} else if (strcmp(key, "remote") == 0) {
		if (parent->service != NULL)
			ctx->error = "protocol { remote { .. } } not allowed (use remote { protocol { .. } } instead)";
		else if (config_parse_net(value, &filter->remote_net,
					  &filter->remote_bits, &error) < 0)
			ctx->error = p_strdup(ctx->pool, error);
		else if (parent->remote_bits > filter->remote_bits ||
			 (parent->remote_bits > 0 &&
			  !net_is_in_network(&filter->remote_net,
					     &parent->remote_net,
					     parent->remote_bits)))
			ctx->error = "remote net1 { remote net2 { .. } } requires net2 to be inside net1";
		else
			filter->remote_host = p_strdup(ctx->pool, value);
	} else {
		return FALSE;
	}

	parser = config_filter_parser_find(ctx, filter);
	if (parser != NULL)
		ctx->cur_section->parsers = parser->parsers;
	else
		config_add_new_parser(ctx);
	return TRUE;
}

static int
config_filter_parser_check(struct config_parser_context *ctx,
			   const struct config_module_parser *p,
			   const char **error_r)
{
	const char *error;
	char *error_dup = NULL;
	bool ok;

	for (; p->root != NULL; p++) {
		/* skip checking settings we don't care about */
		if (!config_module_want_parser(ctx->root_parsers,
					       ctx->modules, p->root))
			continue;

		settings_parse_var_skip(p->parser);
		T_BEGIN {
			ok = settings_parser_check(p->parser, ctx->pool, &error);
			if (!ok)
				error_dup = i_strdup(error);
		} T_END;
		if (!ok) {
			i_assert(error_dup != NULL);
			*error_r = t_strdup(error_dup);
			i_free(error_dup);
			return -1;
		}
	}
	return 0;
}

static const char *
get_str_setting(struct config_filter_parser *parser, const char *key,
		const char *default_value)
{
	struct config_module_parser *module_parser;
	const char *const *set_value;
	enum setting_type set_type;

	module_parser = parser->parsers;
	for (; module_parser->parser != NULL; module_parser++) {
		set_value = settings_parse_get_value(module_parser->parser,
						     key, &set_type);
		if (set_value != NULL &&
		    settings_parse_is_changed(module_parser->parser, key)) {
			i_assert(set_type == SET_STR || set_type == SET_ENUM);
			return *set_value;
		}
	}
	return default_value;
}

static int
config_all_parsers_check(struct config_parser_context *ctx,
			 struct config_filter_context *new_filter,
			 const char **error_r)
{
	struct config_filter_parser *const *parsers;
	struct config_module_parser *tmp_parsers;
	struct master_service_settings_output output;
	unsigned int i, count;
	const char *ssl_set, *global_ssl_set;
	pool_t tmp_pool;
	bool ssl_warned = FALSE;
	int ret = 0;

	if (ctx->cur_section->prev != NULL) {
		*error_r = t_strdup_printf(
			"Missing '}' (section started at %s:%u)",
			ctx->cur_section->open_path,
			ctx->cur_section->open_linenum);
		return -1;
	}

	tmp_pool = pool_alloconly_create(MEMPOOL_GROWING"config parsers check", 1024*64);
	parsers = array_get(&ctx->all_parsers, &count);
	i_assert(count > 0 && parsers[count-1] == NULL);
	count--;

	global_ssl_set = get_str_setting(parsers[0], "ssl", "");
	for (i = 0; i < count && ret == 0; i++) {
		if (config_filter_parsers_get(new_filter, tmp_pool, NULL,
					      &parsers[i]->filter,
					      &tmp_parsers, &output,
					      error_r) < 0) {
			ret = -1;
			break;
		}

		ssl_set = get_str_setting(parsers[i], "ssl", global_ssl_set);
		if (strcmp(ssl_set, "no") != 0 &&
		    strcmp(global_ssl_set, "no") == 0 && !ssl_warned) {
			i_warning("SSL is disabled because global ssl=no, "
				  "ignoring ssl=%s for subsection", ssl_set);
			ssl_warned = TRUE;
		}

		ret = config_filter_parser_check(ctx, tmp_parsers, error_r);
		config_filter_parsers_free(tmp_parsers);
		p_clear(tmp_pool);
	}
	pool_unref(&tmp_pool);
	return ret;
}

static int
str_append_file(string_t *str, const char *key, const char *path,
		const char **error_r)
{
	unsigned char buf[1024];
	int fd;
	ssize_t ret;

	*error_r = NULL;

	fd = open(path, O_RDONLY);
	if (fd == -1) {
		*error_r = t_strdup_printf("%s: Can't open file %s: %m",
					   key, path);
		return -1;
	}
	while ((ret = read(fd, buf, sizeof(buf))) > 0)
		str_append_n(str, buf, ret);
	if (ret < 0) {
		*error_r = t_strdup_printf("%s: read(%s) failed: %m",
					   key, path);
	}
	i_close_fd(&fd);
	return ret < 0 ? -1 : 0;
}

static int settings_add_include(struct config_parser_context *ctx, const char *path,
				bool ignore_errors, const char **error_r)
{
	struct input_stack *tmp, *new_input;
	int fd;

	for (tmp = ctx->cur_input; tmp != NULL; tmp = tmp->prev) {
		if (strcmp(tmp->path, path) == 0)
			break;
	}
	if (tmp != NULL) {
		*error_r = t_strdup_printf("Recursive include file: %s", path);
		return -1;
	}

	if ((fd = open(path, O_RDONLY)) == -1) {
		if (ignore_errors)
			return 0;

		*error_r = t_strdup_printf("Couldn't open include file %s: %m",
					   path);
		return -1;
	}

	new_input = p_new(ctx->pool, struct input_stack, 1);
	new_input->prev = ctx->cur_input;
	new_input->path = p_strdup(ctx->pool, path);
	new_input->input = i_stream_create_fd_autoclose(&fd, (size_t)-1);
	i_stream_set_return_partial_line(new_input->input, TRUE);
	ctx->cur_input = new_input;
	return 0;
}

static int
settings_include(struct config_parser_context *ctx, const char *pattern,
		 bool ignore_errors)
{
	const char *error;
#ifdef HAVE_GLOB
	glob_t globbers;
	unsigned int i;

	switch (glob(pattern, GLOB_BRACE, NULL, &globbers)) {
	case 0:
		break;
	case GLOB_NOSPACE:
		ctx->error = "glob() failed: Not enough memory";
		return -1;
	case GLOB_ABORTED:
		ctx->error = "glob() failed: Read error";
		return -1;
	case GLOB_NOMATCH:
		if (ignore_errors)
			return 0;
		ctx->error = "No matches";
		return -1;
	default:
		ctx->error = "glob() failed: Unknown error";
		return -1;
	}

	/* iterate throuth the different files matching the globbing */
	for (i = globbers.gl_pathc; i > 0; i--) {
		if (settings_add_include(ctx, globbers.gl_pathv[i-1],
					 ignore_errors, &error) < 0) {
			ctx->error = p_strdup(ctx->pool, error);
			return -1;
		}
	}
	globfree(&globbers);
	return 0;
#else
	if (settings_add_include(ctx, pattern, ignore_errors, &error) < 0) {
		ctx->error = p_strdup(ctx->pool, error);
		return -1;
	}
	return 0;
#endif
}

static enum config_line_type
config_parse_line(struct config_parser_context *ctx,
		  char *line, string_t *full_line,
		  const char **key_r, const char **value_r)
{
	const char *key;
	size_t len;
	char *p;

	*key_r = NULL;
	*value_r = NULL;

	/* @UNSAFE: line is modified */

	/* skip whitespace */
	while (IS_WHITE(*line))
		line++;

	/* ignore comments or empty lines */
	if (*line == '#' || *line == '\0')
		return CONFIG_LINE_TYPE_SKIP;

	/* strip away comments. pretty kludgy way really.. */
	for (p = line; *p != '\0'; p++) {
		if (*p == '\'' || *p == '"') {
			char quote = *p;
			for (p++; *p != quote && *p != '\0'; p++) {
				if (*p == '\\' && p[1] != '\0')
					p++;
			}
			if (*p == '\0')
				break;
		} else if (*p == '#') {
			if (!IS_WHITE(p[-1])) {
				i_warning("Configuration file %s line %u: "
					  "Ambiguous '#' character in line, treating it as comment. "
					  "Add a space before it to remove this warning.",
					  ctx->cur_input->path,
					  ctx->cur_input->linenum);
			}
			*p = '\0';
			break;
		}
	}

	/* remove whitespace from end of line */
	len = strlen(line);
	while (len >= 1) {
		if(!IS_WHITE(line[len-1]))
			break;
		len--;
	}
	line[len] = '\0';

	if (len >= 1 && line[len-1] == '\\') {
		/* continues in next line */
		len--;
		while (len >= 1) {
			if(!IS_WHITE(line[len-1]))
				break;
			len--;
		}
		if(len >= 1) {
			str_append_n(full_line, line, len);
			str_append_c(full_line, ' ');
		}
		return CONFIG_LINE_TYPE_CONTINUE;
	}
	if (str_len(full_line) > 0) {
		str_append(full_line, line);
		line = str_c_modifiable(full_line);
	}

	/* a) key = value
	   b) section_type [section_name] {
	   c) } */
	key = line;
	while (!IS_WHITE(*line) && *line != '\0' && *line != '=')
		line++;
	if (IS_WHITE(*line)) {
		*line++ = '\0';
		while (IS_WHITE(*line)) line++;
	}
	*key_r = key;
	*value_r = line;

	if (strcmp(key, "!include") == 0)
		return CONFIG_LINE_TYPE_INCLUDE;
	if (strcmp(key, "!include_try") == 0)
		return CONFIG_LINE_TYPE_INCLUDE_TRY;

	if (*line == '=') {
		/* a) */
		*line++ = '\0';
		while (IS_WHITE(*line)) line++;

		if (*line == '<') {
			while (IS_WHITE(line[1])) line++;
			*value_r = line + 1;
			return CONFIG_LINE_TYPE_KEYFILE;
		}
		if (*line == '$') {
			*value_r = line + 1;
			return CONFIG_LINE_TYPE_KEYVARIABLE;
		}

		len = strlen(line);
		if (len > 0 &&
		    ((*line == '"' && line[len-1] == '"') ||
		     (*line == '\'' && line[len-1] == '\''))) {
			line[len-1] = '\0';
			line = str_unescape(line+1);
		}
		*value_r = line;
		return CONFIG_LINE_TYPE_KEYVALUE;
	}

	if (strcmp(key, "}") == 0 && *line == '\0')
		return CONFIG_LINE_TYPE_SECTION_END;

	/* b) + errors */
	line[-1] = '\0';

	if (*line == '{')
		*value_r = "";
	else {
		/* get section name */
		if (*line != '"') {
			*value_r = line;
			while (!IS_WHITE(*line) && *line != '\0')
				line++;
			if (*line != '\0') {
				*line++ = '\0';
				while (IS_WHITE(*line))
					line++;
			}
		} else {
			char *value = ++line;
			while (*line != '"' && *line != '\0')
				line++;
			if (*line == '"') {
				*line++ = '\0';
				while (IS_WHITE(*line))
					line++;
				*value_r = str_unescape(value);
			}
		}
		if (*line != '{') {
			*value_r = "Expecting '{'";
			return CONFIG_LINE_TYPE_ERROR;
		}
	}
	if (line[1] != '\0') {
		*value_r = "Garbage after '{'";
		return CONFIG_LINE_TYPE_ERROR;
	}
	return CONFIG_LINE_TYPE_SECTION_BEGIN;
}

static int config_parse_finish(struct config_parser_context *ctx, const char **error_r)
{
	struct config_filter_context *new_filter;
	const char *error;
	int ret = 0;

	if (hook_config_parser_end != NULL)
		ret = hook_config_parser_end(ctx, error_r);

	new_filter = config_filter_init(ctx->pool);
	array_append_zero(&ctx->all_parsers);
	config_filter_add_all(new_filter, array_idx(&ctx->all_parsers, 0));

	if (ret < 0)
		;
	else if (ctx->hide_errors)
		ret = 0;
	else if ((ret = config_all_parsers_check(ctx, new_filter, &error)) < 0) {
		*error_r = t_strdup_printf("Error in configuration file %s: %s",
					   ctx->path, error);
	}

	if (config_filter != NULL)
		config_filter_deinit(&config_filter);
	config_module_parsers = ctx->root_parsers;
	config_filter = new_filter;
	return ret;
}

static const void *
config_get_value(struct config_section_stack *section, const char *key,
		 bool expand_parent, enum setting_type *type_r)
{
	struct config_module_parser *l;
	const void *value;

	for (l = section->parsers; l->root != NULL; l++) {
		value = settings_parse_get_value(l->parser, key, type_r);
		if (value != NULL) {
			if (!expand_parent || section->prev == NULL ||
			    settings_parse_is_changed(l->parser, key))
				return value;

			/* not changed by this parser. maybe parent has. */
			return config_get_value(section->prev,
						key, TRUE, type_r);
		}
	}
	return NULL;
}

static bool
config_require_key(struct config_parser_context *ctx, const char *key)
{
	struct config_module_parser *l;

	if (ctx->modules == NULL)
		return TRUE;

	for (l = ctx->cur_section->parsers; l->root != NULL; l++) {
		if (config_module_want_parser(ctx->root_parsers,
					      ctx->modules, l->root) &&
		    settings_parse_is_valid_key(l->parser, key))
			return TRUE;
	}
	return FALSE;
}

static int config_write_value(struct config_parser_context *ctx,
			      enum config_line_type type,
			      const char *key, const char *value)
{
	string_t *str = ctx->str;
	const void *var_name, *var_value, *p;
	enum setting_type var_type;
	const char *error, *path;
	bool dump, expand_parent;

	switch (type) {
	case CONFIG_LINE_TYPE_KEYVALUE:
		str_append(str, value);
		break;
	case CONFIG_LINE_TYPE_KEYFILE:
		if (!ctx->expand_values) {
			str_append_c(str, '<');
			str_append(str, value);
		} else {
			if (!config_require_key(ctx, key)) {
				/* don't even try to open the file */
			} else {
				path = fix_relative_path(value, ctx->cur_input);
				if (str_append_file(str, key, path, &error) < 0) {
					/* file reading failed */
					ctx->error = p_strdup(ctx->pool, error);
					return -1;
				}
			}
		}
		break;
	case CONFIG_LINE_TYPE_KEYVARIABLE:
		/* expand_parent=TRUE for "key = $key stuff".
		   we'll always expand it so that doveconf -n can give
		   usable output */
		p = strchr(value, ' ');
		if (p == NULL)
			var_name = value;
		else
			var_name = t_strdup_until(value, p);
		expand_parent = strcmp(key, var_name) == 0;

		if (!ctx->expand_values && !expand_parent) {
			str_append_c(str, '$');
			str_append(str, value);
		} else {
			var_value = config_get_value(ctx->cur_section, var_name,
						     expand_parent, &var_type);
			if (var_value == NULL) {
				ctx->error = p_strconcat(ctx->pool,
							 "Unknown variable: $",
							 var_name, NULL);
				return -1;
			}
			if (!config_export_type(str, var_value, NULL,
						var_type, TRUE, &dump)) {
				ctx->error = p_strconcat(ctx->pool,
							 "Invalid variable: $",
							 var_name, NULL);
				return -1;
			}
			if (p != NULL)
				str_append(str, p);
		}
		break;
	default:
		i_unreached();
	}
	return 0;
}

static void
config_parser_check_warnings(struct config_parser_context *ctx, const char *key)
{
	const char *path, *first_pos;

	first_pos = hash_table_lookup(ctx->seen_settings, str_c(ctx->str));
	if (ctx->cur_section->prev == NULL) {
		/* changing a root setting. if we've already seen it inside
		   filters, log a warning. */
		if (first_pos == NULL)
			return;
		i_warning("%s line %u: Global setting %s won't change the setting inside an earlier filter at %s "
			  "(if this is intentional, avoid this warning by moving the global setting before %s)",
			  ctx->cur_input->path, ctx->cur_input->linenum,
			  key, first_pos, first_pos);
		return;
	}
	if (first_pos != NULL)
		return;
	first_pos = p_strdup_printf(ctx->pool, "%s line %u",
				    ctx->cur_input->path, ctx->cur_input->linenum);
	path = p_strdup(ctx->pool, str_c(ctx->str));
	hash_table_insert(ctx->seen_settings, path, first_pos);
}

void config_parser_apply_line(struct config_parser_context *ctx,
			      enum config_line_type type,
			      const char *key, const char *value)
{
	const char *section_name;

	str_truncate(ctx->str, ctx->pathlen);
	switch (type) {
	case CONFIG_LINE_TYPE_SKIP:
		break;
	case CONFIG_LINE_TYPE_CONTINUE:
		i_unreached();
	case CONFIG_LINE_TYPE_ERROR:
		ctx->error = p_strdup(ctx->pool, value);
		break;
	case CONFIG_LINE_TYPE_KEYVALUE:
	case CONFIG_LINE_TYPE_KEYFILE:
	case CONFIG_LINE_TYPE_KEYVARIABLE:
		str_append(ctx->str, key);
		config_parser_check_warnings(ctx, key);
		str_append_c(ctx->str, '=');

		if (config_write_value(ctx, type, key, value) < 0)
			break;
		(void)config_apply_line(ctx, key, str_c(ctx->str), NULL);
		break;
	case CONFIG_LINE_TYPE_SECTION_BEGIN:
		ctx->cur_section = config_add_new_section(ctx);
		ctx->cur_section->pathlen = ctx->pathlen;

		if (config_filter_add_new_filter(ctx, key, value)) {
			/* new filter */
			break;
		}

		/* new config section */
		if (*value == '\0') {
			/* no section name, use a counter */
			section_name = dec2str(ctx->section_counter++);
		} else {
			section_name = settings_section_escape(value);
		}
		str_append(ctx->str, key);
		ctx->pathlen = str_len(ctx->str);

		str_append_c(ctx->str, '=');
		str_append(ctx->str, section_name);

		if (config_apply_line(ctx, key, str_c(ctx->str), value) < 0)
			break;

		str_truncate(ctx->str, ctx->pathlen);
		str_append_c(ctx->str, SETTINGS_SEPARATOR);
		str_append(ctx->str, section_name);
		str_append_c(ctx->str, SETTINGS_SEPARATOR);
		ctx->pathlen = str_len(ctx->str);
		break;
	case CONFIG_LINE_TYPE_SECTION_END:
		if (ctx->cur_section->prev == NULL)
			ctx->error = "Unexpected '}'";
		else {
			ctx->pathlen = ctx->cur_section->pathlen;
			ctx->cur_section = ctx->cur_section->prev;
		}
		break;
	case CONFIG_LINE_TYPE_INCLUDE:
	case CONFIG_LINE_TYPE_INCLUDE_TRY:
		(void)settings_include(ctx, fix_relative_path(value, ctx->cur_input),
				       type == CONFIG_LINE_TYPE_INCLUDE_TRY);
		break;
	}
}

int config_parse_file(const char *path, bool expand_values,
		      const char *const *modules, const char **error_r)
{
	struct input_stack root;
	struct config_parser_context ctx;
	unsigned int i, count;
	const char *key, *value;
	string_t *full_line;
	enum config_line_type type;
	char *line;
	int fd, ret = 0;
	bool handled;

	if (path == NULL) {
		path = "<defaults>";
		fd = -1;
	} else {
		fd = open(path, O_RDONLY);
		if (fd < 0) {
			*error_r = t_strdup_printf("open(%s) failed: %m", path);
			return 0;
		}
	}

	memset(&ctx, 0, sizeof(ctx));
	ctx.pool = pool_alloconly_create(MEMPOOL_GROWING"config file parser", 1024*256);
	ctx.path = path;
	ctx.hide_errors = fd == -1;

	for (count = 0; all_roots[count] != NULL; count++) ;
	ctx.root_parsers =
		p_new(ctx.pool, struct config_module_parser, count+1);
	for (i = 0; i < count; i++) {
		ctx.root_parsers[i].root = all_roots[i];
		ctx.root_parsers[i].parser =
			settings_parser_init(ctx.pool, all_roots[i],
					     settings_parser_flags);
	}

	memset(&root, 0, sizeof(root));
	root.path = path;
	ctx.cur_input = &root;
	ctx.expand_values = expand_values;
	ctx.modules = modules;
	hash_table_create(&ctx.seen_settings, ctx.pool, 0, str_hash, strcmp);

	p_array_init(&ctx.all_parsers, ctx.pool, 128);
	ctx.cur_section = p_new(ctx.pool, struct config_section_stack, 1);
	config_add_new_parser(&ctx);

	ctx.str = str_new(ctx.pool, 256);
	full_line = str_new(default_pool, 512);
	ctx.cur_input->input = fd != -1 ?
		i_stream_create_fd_autoclose(&fd, (size_t)-1) :
		i_stream_create_from_data("", 0);
	i_stream_set_return_partial_line(ctx.cur_input->input, TRUE);
	old_settings_init(&ctx);
	if (hook_config_parser_begin != NULL) T_BEGIN {
		hook_config_parser_begin(&ctx);
	} T_END;

prevfile:
	while ((line = i_stream_read_next_line(ctx.cur_input->input)) != NULL) {
		ctx.cur_input->linenum++;
		type = config_parse_line(&ctx, line, full_line,
					 &key, &value);
		str_truncate(ctx.str, ctx.pathlen);
		if (type == CONFIG_LINE_TYPE_CONTINUE)
			continue;

		T_BEGIN {
			handled = old_settings_handle(&ctx, type, key, value);
			if (!handled)
				config_parser_apply_line(&ctx, type, key, value);
		} T_END;

		if (ctx.error != NULL) {
			*error_r = t_strdup_printf(
				"Error in configuration file %s line %d: %s",
				ctx.cur_input->path, ctx.cur_input->linenum,
				ctx.error);
			ret = -2;
			break;
		}
		str_truncate(full_line, 0);
	}

	i_stream_destroy(&ctx.cur_input->input);
	ctx.cur_input = ctx.cur_input->prev;
	if (line == NULL && ctx.cur_input != NULL)
		goto prevfile;

	hash_table_destroy(&ctx.seen_settings);
	str_free(&full_line);
	if (ret == 0)
		ret = config_parse_finish(&ctx, error_r);
	return ret < 0 ? ret : 1;
}

void config_parse_load_modules(void)
{
	struct module_dir_load_settings mod_set;
	struct module *m;
	const struct setting_parser_info **roots;
	ARRAY_TYPE(setting_parser_info_p) new_roots;
	ARRAY_TYPE(service_settings) new_services;
	struct service_settings *const *services, *service_set;
	unsigned int i, count;

	memset(&mod_set, 0, sizeof(mod_set));
	mod_set.abi_version = DOVECOT_ABI_VERSION;
	modules = module_dir_load(CONFIG_MODULE_DIR, NULL, &mod_set);
	module_dir_init(modules);

	i_array_init(&new_roots, 64);
	i_array_init(&new_services, 64);
	for (m = modules; m != NULL; m = m->next) {
		roots = module_get_symbol_quiet(m,
			t_strdup_printf("%s_set_roots", m->name));
		if (roots != NULL) {
			for (i = 0; roots[i] != NULL; i++)
				array_append(&new_roots, &roots[i], 1);
		}

		services = module_get_symbol_quiet(m,
			t_strdup_printf("%s_service_settings_array", m->name));
		if (services != NULL) {
			for (count = 0; services[count] != NULL; count++) ;
			array_append(&new_services, services, count);
		} else {
			service_set = module_get_symbol_quiet(m,
				t_strdup_printf("%s_service_settings", m->name));
			if (service_set != NULL)
				array_append(&new_services, &service_set, 1);
		}
	}
	if (array_count(&new_roots) > 0) {
		/* modules added new settings. add the defaults and start
		   using the new list. */
		for (i = 0; all_roots[i] != NULL; i++)
			array_append(&new_roots, &all_roots[i], 1);
		array_append_zero(&new_roots);
		all_roots = array_idx(&new_roots, 0);
		roots_free_at_deinit = new_roots;
	} else {
		array_free(&new_roots);
	}
	if (array_count(&new_services) > 0) {
		/* module added new services. update the defaults. */
		services = array_get(default_services, &count);
		for (i = 0; i < count; i++)
			array_append(&new_services, &services[i], 1);
		*default_services = new_services;
		services_free_at_deinit = new_services;
	} else {
		array_free(&new_services);
	}
}

static bool parsers_are_connected(const struct setting_parser_info *root,
				  const struct setting_parser_info *info)
{
	const struct setting_parser_info *p;
	const struct setting_parser_info *const *dep;

	/* we're trying to find info or its parents from root's dependencies. */

	for (p = info; p != NULL; p = p->parent) {
		if (p == root)
			return TRUE;
	}

	if (root->dependencies != NULL) {
		for (dep = root->dependencies; *dep != NULL; dep++) {
			if (parsers_are_connected(*dep, info))
				return TRUE;
		}
	}
	return FALSE;
}

bool config_module_want_parser(struct config_module_parser *parsers,
			       const char *const *modules,
			       const struct setting_parser_info *root)
{
	struct config_module_parser *l;

	if (modules == NULL)
		return TRUE;
	if (root == &master_service_setting_parser_info) {
		/* everyone wants master service settings */
		return TRUE;
	}

	for (l = parsers; l->root != NULL; l++) {
		if (!str_array_find(modules, l->root->module_name))
			continue;

		/* see if we can find a way to get from the original parser
		   to this parser */
		if (parsers_are_connected(l->root, root))
			return TRUE;
	}
	return FALSE;
}

void config_parser_deinit(void)
{
	if (array_is_created(&services_free_at_deinit))
		array_free(&services_free_at_deinit);
	if (array_is_created(&roots_free_at_deinit))
		array_free(&roots_free_at_deinit);
}