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mail-storage-service.c
1726 lines (1514 loc) · 50.5 KB
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mail-storage-service.c
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/* Copyright (c) 2009-2017 Dovecot authors, see the included COPYING file */
#include "lib.h"
#include "ioloop.h"
#include "array.h"
#include "base64.h"
#include "hostpid.h"
#include "module-dir.h"
#include "restrict-access.h"
#include "eacces-error.h"
#include "ipwd.h"
#include "str.h"
#include "var-expand.h"
#include "dict.h"
#include "settings-parser.h"
#include "auth-master.h"
#include "master-service-private.h"
#include "master-service-settings.h"
#include "master-service-settings-cache.h"
#include "mail-user.h"
#include "mail-namespace.h"
#include "mail-storage.h"
#include "mail-storage-service.h"
#include <sys/stat.h>
#ifdef HAVE_SYS_TIME_H
# include <sys/time.h>
#endif
#ifdef HAVE_SYS_RESOURCE_H
# include <sys/resource.h>
#endif
/* If time moves backwards more than this, kill ourself instead of sleeping. */
#define MAX_TIME_BACKWARDS_SLEEP 5
#define MAX_NOWARN_FORWARD_SECS 10
#define ERRSTR_INVALID_USER_SETTINGS \
"Invalid user settings. Refer to server log for more information."
struct mail_storage_service_privileges {
uid_t uid;
gid_t gid;
const char *uid_source, *gid_source;
const char *home;
const char *chroot;
};
struct mail_storage_service_ctx {
pool_t pool;
struct master_service *service;
const char *default_log_prefix;
struct auth_master_connection *conn, *iter_conn;
struct auth_master_user_list_ctx *auth_list;
const struct setting_parser_info **set_roots;
enum mail_storage_service_flags flags;
const char *set_cache_module, *set_cache_service;
struct master_service_settings_cache *set_cache;
pool_t userdb_next_pool;
const char *const **userdb_next_fieldsp;
bool debug:1;
bool log_initialized:1;
bool config_permission_denied:1;
};
struct mail_storage_service_user {
pool_t pool;
int refcount;
struct mail_storage_service_ctx *service_ctx;
struct mail_storage_service_input input;
enum mail_storage_service_flags flags;
struct ioloop_context *ioloop_ctx;
const char *log_prefix, *auth_token, *auth_user;
const char *system_groups_user, *uid_source, *gid_source;
const char *chdir_path;
const struct mail_user_settings *user_set;
const struct setting_parser_info *user_info;
struct setting_parser_context *set_parser;
unsigned int session_id_counter;
bool anonymous:1;
bool admin:1;
};
struct module *mail_storage_service_modules = NULL;
static int
mail_storage_service_var_expand(struct mail_storage_service_ctx *ctx,
string_t *str, const char *format,
struct mail_storage_service_user *user,
const struct mail_storage_service_input *input,
const struct mail_storage_service_privileges *priv,
const char **error_r);
static bool
mail_user_set_get_mail_debug(const struct setting_parser_info *user_info,
const struct mail_user_settings *user_set)
{
const struct mail_storage_settings *mail_set;
mail_set = mail_user_set_get_driver_settings(user_info, user_set,
MAIL_STORAGE_SET_DRIVER_NAME);
return mail_set->mail_debug;
}
static void set_keyval(struct mail_storage_service_ctx *ctx,
struct mail_storage_service_user *user,
const char *key, const char *value)
{
struct setting_parser_context *set_parser = user->set_parser;
if (master_service_set_has_config_override(ctx->service, key)) {
/* this setting was already overridden with -o parameter */
if (mail_user_set_get_mail_debug(user->user_info,
user->user_set)) {
i_debug("Ignoring overridden (-o) userdb setting: %s",
key);
}
return;
}
if (settings_parse_keyvalue(set_parser, key, value) < 0) {
i_fatal("Invalid userdb input %s=%s: %s", key, value,
settings_parser_get_error(set_parser));
}
}
static int set_line(struct mail_storage_service_ctx *ctx,
struct mail_storage_service_user *user,
const char *line)
{
struct setting_parser_context *set_parser = user->set_parser;
bool mail_debug;
const char *key, *orig_key, *append_value = NULL;
size_t len;
int ret;
mail_debug = mail_user_set_get_mail_debug(user->user_info,
user->user_set);
if (strchr(line, '=') == NULL)
line = t_strconcat(line, "=yes", NULL);
orig_key = key = t_strcut(line, '=');
len = strlen(key);
if (len > 0 && key[len-1] == '+') {
/* key+=value */
append_value = line + len + 1;
key = t_strndup(key, len-1);
}
if (!settings_parse_is_valid_key(set_parser, key)) {
/* assume it's a plugin setting */
key = t_strconcat("plugin/", key, NULL);
line = t_strconcat("plugin/", line, NULL);
}
if (master_service_set_has_config_override(ctx->service, key)) {
/* this setting was already overridden with -o parameter */
if (mail_debug) {
i_debug("Ignoring overridden (-o) userdb setting: %s",
key);
}
return 1;
}
if (append_value != NULL) {
const void *value;
enum setting_type type;
value = settings_parse_get_value(set_parser, key, &type);
if (value != NULL && type == SET_STR) {
const char *const *strp = value;
line = t_strdup_printf("%s=%s%s",
key, *strp, append_value);
} else {
i_error("Ignoring %s userdb setting. "
"'+' can only be used for strings.", orig_key);
}
}
ret = settings_parse_line(set_parser, line);
if (mail_debug && ret >= 0) {
if (strstr(key, "pass") != NULL) {
/* possibly a password field (e.g. imapc_password).
hide the value. */
line = t_strconcat(key, "=<hidden>", NULL);
}
i_debug(ret == 0 ?
"Unknown userdb setting: %s" :
"Added userdb setting: %s", line);
}
return ret;
}
static bool validate_chroot(const struct mail_user_settings *user_set,
const char *dir)
{
const char *const *chroot_dirs;
if (*dir == '\0')
return FALSE;
if (*user_set->valid_chroot_dirs == '\0')
return FALSE;
chroot_dirs = t_strsplit(user_set->valid_chroot_dirs, ":");
while (*chroot_dirs != NULL) {
if (**chroot_dirs != '\0' &&
strncmp(dir, *chroot_dirs, strlen(*chroot_dirs)) == 0)
return TRUE;
chroot_dirs++;
}
return FALSE;
}
static int
user_reply_handle(struct mail_storage_service_ctx *ctx,
struct mail_storage_service_user *user,
const struct auth_user_reply *reply,
const char **error_r)
{
const char *home = reply->home;
const char *chroot = reply->chroot;
const char *const *str, *line, *p;
unsigned int i, count;
int ret = 0;
if (reply->uid != (uid_t)-1) {
if (reply->uid == 0) {
*error_r = "userdb returned 0 as uid";
return -1;
}
user->uid_source = "userdb lookup";
set_keyval(ctx, user, "mail_uid", dec2str(reply->uid));
}
if (reply->gid != (uid_t)-1) {
user->gid_source = "userdb lookup";
set_keyval(ctx, user, "mail_gid", dec2str(reply->gid));
}
if (home != NULL && chroot == NULL &&
*user->user_set->valid_chroot_dirs != '\0' &&
(p = strstr(home, "/./")) != NULL) {
/* wu-ftpd like <chroot>/./<home> - check only if there's even
a possibility of using them (non-empty valid_chroot_dirs) */
chroot = t_strdup_until(home, p);
home = p + 2;
}
if (home != NULL)
set_keyval(ctx, user, "mail_home", home);
if (chroot != NULL) {
if (!validate_chroot(user->user_set, chroot)) {
*error_r = t_strdup_printf(
"userdb returned invalid chroot directory: %s "
"(see valid_chroot_dirs setting)", chroot);
return -1;
}
set_keyval(ctx, user, "mail_chroot", chroot);
}
user->anonymous = reply->anonymous;
str = array_get(&reply->extra_fields, &count);
for (i = 0; i < count; i++) {
line = str[i];
if (strncmp(line, "system_groups_user=", 19) == 0) {
user->system_groups_user =
p_strdup(user->pool, line + 19);
} else if (strncmp(line, "chdir=", 6) == 0) {
user->chdir_path = p_strdup(user->pool, line+6);
} else if (strncmp(line, "nice=", 5) == 0) {
#ifdef HAVE_SETPRIORITY
int n;
if (str_to_int(line + 5, &n) < 0) {
i_error("userdb returned invalid nice value %s",
line + 5);
} else if (n != 0) {
if (setpriority(PRIO_PROCESS, 0, n) < 0)
i_error("setpriority(%d) failed: %m", n);
}
#endif
} else if (strncmp(line, "auth_token=", 11) == 0) {
user->auth_token = p_strdup(user->pool, line+11);
} else if (strncmp(line, "auth_user=", 10) == 0) {
user->auth_user = p_strdup(user->pool, line+10);
} else if (strncmp(line, "admin=", 6) == 0) {
user->admin = line[6] == 'y' || line[6] == 'Y' ||
line[6] == '1';
} else T_BEGIN {
ret = set_line(ctx, user, line);
} T_END;
if (ret < 0)
break;
}
if (ret < 0) {
*error_r = t_strdup_printf("Invalid userdb input '%s': %s",
str[i], settings_parser_get_error(user->set_parser));
}
return ret;
}
static int
service_auth_userdb_lookup(struct mail_storage_service_ctx *ctx,
const struct mail_storage_service_input *input,
pool_t pool, const char **user,
const char *const **fields_r,
const char **error_r)
{
struct auth_user_info info;
const char *new_username;
int ret;
i_zero(&info);
info.service = input->service != NULL ? input->service :
ctx->service->name;
info.local_ip = input->local_ip;
info.remote_ip = input->remote_ip;
info.local_port = input->local_port;
info.remote_port = input->remote_port;
info.debug = input->debug;
ret = auth_master_user_lookup(ctx->conn, *user, &info, pool,
&new_username, fields_r);
if (ret > 0) {
if (strcmp(*user, new_username) != 0) {
if (ctx->debug)
i_debug("changed username to %s", new_username);
*user = t_strdup(new_username);
}
*user = new_username;
} else if (ret == 0)
*error_r = "Unknown user";
else if (**fields_r != NULL) {
*error_r = t_strdup(**fields_r);
ret = -2;
} else {
*error_r = MAIL_ERRSTR_CRITICAL_MSG;
}
return ret;
}
static bool parse_uid(const char *str, uid_t *uid_r, const char **error_r)
{
struct passwd pw;
if (str_to_uid(str, uid_r) == 0)
return TRUE;
switch (i_getpwnam(str, &pw)) {
case -1:
*error_r = t_strdup_printf("getpwnam(%s) failed: %m", str);
return FALSE;
case 0:
*error_r = t_strconcat("Unknown UNIX UID user: ", str, NULL);
return FALSE;
default:
*uid_r = pw.pw_uid;
return TRUE;
}
}
static bool parse_gid(const char *str, gid_t *gid_r, const char **error_r)
{
struct group gr;
if (str_to_gid(str, gid_r) == 0)
return TRUE;
switch (i_getgrnam(str, &gr)) {
case -1:
*error_r = t_strdup_printf("getgrnam(%s) failed: %m", str);
return FALSE;
case 0:
*error_r = t_strconcat("Unknown UNIX GID group: ", str, NULL);
return FALSE;
default:
*gid_r = gr.gr_gid;
return TRUE;
}
}
static const struct var_expand_table *
get_var_expand_table(struct master_service *service,
struct mail_storage_service_user *user,
const struct mail_storage_service_input *input,
const struct mail_storage_service_privileges *priv)
{
const char *username = t_strcut(input->username, '@');
const char *domain = i_strchr_to_next(input->username, '@');
const char *uid = priv == NULL ? NULL :
dec2str(priv->uid == (uid_t)-1 ? geteuid() : priv->uid);
const char *gid = priv == NULL ? NULL :
dec2str(priv->gid == (gid_t)-1 ? getegid() : priv->gid);
const char *auth_user, *auth_username, *auth_domain;
if (user == NULL || user->auth_user == NULL) {
auth_user = input->username;
auth_username = username;
auth_domain = domain;
} else {
auth_user = user->auth_user;
auth_username = t_strcut(user->auth_user, '@');
auth_domain = i_strchr_to_next(user->auth_user, '@');
}
const struct var_expand_table stack_tab[] = {
{ 'u', input->username, "user" },
{ 'n', username, "username" },
{ 'd', domain, "domain" },
{ 's', service->name, "service" },
{ 'l', net_ip2addr(&input->local_ip), "lip" },
{ 'r', net_ip2addr(&input->remote_ip), "rip" },
{ 'p', my_pid, "pid" },
{ 'i', uid, "uid" },
{ '\0', gid, "gid" },
{ '\0', input->session_id, "session" },
{ '\0', auth_user, "auth_user" },
{ '\0', auth_username, "auth_username" },
{ '\0', auth_domain, "auth_domain" },
{ '\0', NULL, NULL }
};
struct var_expand_table *tab;
tab = t_malloc_no0(sizeof(stack_tab));
memcpy(tab, stack_tab, sizeof(stack_tab));
return tab;
}
const struct var_expand_table *
mail_storage_service_get_var_expand_table(struct mail_storage_service_ctx *ctx,
struct mail_storage_service_input *input)
{
struct mail_storage_service_privileges priv;
i_zero(&priv);
priv.uid = (uid_t)-1;
priv.gid = (gid_t)-1;
return get_var_expand_table(ctx->service, NULL, input, &priv);
}
static bool
user_expand_varstr(struct mail_storage_service_ctx *ctx,
struct mail_storage_service_user *user,
struct mail_storage_service_privileges *priv,
const char *str, const char **value_r, const char **error_r)
{
string_t *value;
int ret;
if (*str == SETTING_STRVAR_EXPANDED[0]) {
*value_r = str + 1;
return TRUE;
}
i_assert(*str == SETTING_STRVAR_UNEXPANDED[0]);
value = t_str_new(256);
ret = mail_storage_service_var_expand(ctx, value, str + 1, user,
&user->input, priv, error_r);
*value_r = str_c(value);
return ret > 0;
}
static int
service_parse_privileges(struct mail_storage_service_ctx *ctx,
struct mail_storage_service_user *user,
struct mail_storage_service_privileges *priv_r,
const char **error_r)
{
const struct mail_user_settings *set = user->user_set;
uid_t uid = (uid_t)-1;
gid_t gid = (gid_t)-1;
const char *error;
i_zero(priv_r);
if (*set->mail_uid != '\0') {
if (!parse_uid(set->mail_uid, &uid, error_r)) {
*error_r = t_strdup_printf("%s (from %s)", *error_r,
user->uid_source);
return -1;
}
if (uid < (uid_t)set->first_valid_uid ||
(set->last_valid_uid != 0 &&
uid > (uid_t)set->last_valid_uid)) {
*error_r = t_strdup_printf(
"Mail access for users with UID %s not permitted "
"(see first_valid_uid in config file, uid from %s).",
dec2str(uid), user->uid_source);
return -1;
}
}
priv_r->uid = uid;
priv_r->uid_source = user->uid_source;
if (*set->mail_gid != '\0') {
if (!parse_gid(set->mail_gid, &gid, error_r)) {
*error_r = t_strdup_printf("%s (from %s)", *error_r,
user->gid_source);
return -1;
}
if (gid < (gid_t)set->first_valid_gid ||
(set->last_valid_gid != 0 &&
gid > (gid_t)set->last_valid_gid)) {
*error_r = t_strdup_printf(
"Mail access for users with GID %s not permitted "
"(see first_valid_gid in config file, gid from %s).",
dec2str(gid), user->gid_source);
return -1;
}
}
priv_r->gid = gid;
priv_r->gid_source = user->gid_source;
/* variable strings are expanded in mail_user_init(),
but we need the home and chroot sooner so do them separately here. */
if (!user_expand_varstr(ctx, user, priv_r, user->user_set->mail_home,
&priv_r->home, &error)) {
*error_r = t_strdup_printf(
"Failed to expand mail_home '%s': %s",
user->user_set->mail_home, error);
return -1;
}
if (!user_expand_varstr(ctx, user, priv_r, user->user_set->mail_chroot,
&priv_r->chroot, &error)) {
*error_r = t_strdup_printf(
"Failed to expand mail_chroot '%s': %s",
user->user_set->mail_chroot, error);
return -1;
}
return 0;
}
static void mail_storage_service_seteuid_root(void)
{
if (seteuid(0) < 0) {
i_fatal("mail-storage-service: "
"Failed to restore temporarily dropped root privileges: "
"seteuid(0) failed: %m");
}
}
static int
service_drop_privileges(struct mail_storage_service_user *user,
struct mail_storage_service_privileges *priv,
bool disallow_root, bool keep_setuid_root,
bool setenv_only, const char **error_r)
{
const struct mail_user_settings *set = user->user_set;
struct restrict_access_settings rset;
uid_t current_euid, setuid_uid = 0;
const char *cur_chroot, *error;
current_euid = geteuid();
restrict_access_init(&rset);
restrict_access_get_env(&rset);
if (priv->uid != (uid_t)-1) {
rset.uid = priv->uid;
rset.uid_source = priv->uid_source;
} else if (rset.uid == (uid_t)-1 &&
disallow_root && current_euid == 0) {
*error_r = "User is missing UID (see mail_uid setting)";
return -1;
}
if (priv->gid != (gid_t)-1) {
rset.gid = priv->gid;
rset.gid_source = priv->gid_source;
} else if (rset.gid == (gid_t)-1 && disallow_root &&
set->first_valid_gid > 0 && getegid() == 0) {
*error_r = "User is missing GID (see mail_gid setting)";
return -1;
}
if (*set->mail_privileged_group != '\0') {
if (!parse_gid(set->mail_privileged_group, &rset.privileged_gid,
&error)) {
*error_r = t_strdup_printf(
"%s (in mail_privileged_group setting)", error);
return -1;
}
}
if (*set->mail_access_groups != '\0') {
rset.extra_groups = t_strconcat(set->mail_access_groups, ",",
rset.extra_groups, NULL);
}
rset.first_valid_gid = set->first_valid_gid;
rset.last_valid_gid = set->last_valid_gid;
rset.chroot_dir = *priv->chroot == '\0' ? NULL : priv->chroot;
rset.system_groups_user = user->system_groups_user;
cur_chroot = restrict_access_get_current_chroot();
if (cur_chroot != NULL) {
/* we're already chrooted. make sure the chroots are equal. */
if (rset.chroot_dir == NULL) {
*error_r = "Process is already chrooted, "
"can't un-chroot for this user";
return -1;
}
if (strcmp(rset.chroot_dir, cur_chroot) != 0) {
*error_r = t_strdup_printf(
"Process is already chrooted to %s, "
"can't chroot to %s", cur_chroot, priv->chroot);
return -1;
}
/* chrooting to same directory where we're already chrooted */
rset.chroot_dir = NULL;
}
if (disallow_root &&
(rset.uid == 0 || (rset.uid == (uid_t)-1 && current_euid == 0))) {
*error_r = "Mail access not allowed for root";
return -1;
}
if (keep_setuid_root) {
if (current_euid != rset.uid && rset.uid != (uid_t)-1) {
if (current_euid != 0) {
/* we're changing the UID,
switch back to root first */
mail_storage_service_seteuid_root();
}
setuid_uid = rset.uid;
}
rset.uid = (uid_t)-1;
disallow_root = FALSE;
}
if (!setenv_only) {
restrict_access(&rset, *priv->home == '\0' ? NULL : priv->home,
disallow_root);
} else {
restrict_access_set_env(&rset);
}
if (setuid_uid != 0 && !setenv_only) {
if (seteuid(setuid_uid) < 0)
i_fatal("mail-storage-service: seteuid(%s) failed: %m",
dec2str(setuid_uid));
}
return 0;
}
static int
mail_storage_service_init_post(struct mail_storage_service_ctx *ctx,
struct mail_storage_service_user *user,
struct mail_storage_service_privileges *priv,
const char *session_id_suffix,
struct mail_user **mail_user_r,
const char **error_r)
{
const struct mail_storage_settings *mail_set;
const char *home = priv->home;
struct mail_user_connection_data conn_data;
struct mail_user *mail_user;
i_zero(&conn_data);
conn_data.local_ip = &user->input.local_ip;
conn_data.remote_ip = &user->input.remote_ip;
conn_data.local_port = user->input.local_port;
conn_data.remote_port = user->input.remote_port;
conn_data.secured = user->input.conn_secured;
conn_data.ssl_secured = user->input.conn_ssl_secured;
/* NOTE: if more user initialization is added, add it also to
mail_user_dup() */
mail_user = mail_user_alloc_nodup_set(user->input.username,
user->user_info, user->user_set);
mail_user->_service_user = user;
mail_storage_service_user_ref(user);
mail_user_set_home(mail_user, *home == '\0' ? NULL : home);
mail_user_set_vars(mail_user, ctx->service->name, &conn_data);
mail_user->uid = priv->uid == (uid_t)-1 ? geteuid() : priv->uid;
mail_user->gid = priv->gid == (gid_t)-1 ? getegid() : priv->gid;
mail_user->anonymous = user->anonymous;
mail_user->admin = user->admin;
mail_user->auth_token = p_strdup(mail_user->pool, user->auth_token);
mail_user->auth_user = p_strdup(mail_user->pool, user->auth_user);
if (user->input.session_create_time != 0) {
mail_user->session_create_time =
user->input.session_create_time;
mail_user->session_restored = TRUE;
}
if (session_id_suffix == NULL) {
if (user->session_id_counter++ == 0) {
mail_user->session_id =
p_strdup(mail_user->pool, user->input.session_id);
} else {
mail_user->session_id =
p_strdup_printf(mail_user->pool, "%s:%u",
user->input.session_id,
user->session_id_counter);
}
} else
mail_user->session_id =
p_strdup_printf(mail_user->pool, "%s:%s",
user->input.session_id,
session_id_suffix);
mail_user->userdb_fields = user->input.userdb_fields == NULL ? NULL :
p_strarray_dup(mail_user->pool, user->input.userdb_fields);
mail_set = mail_user_set_get_storage_set(mail_user);
if (mail_set->mail_debug) {
string_t *str = t_str_new(64);
str_printfa(str, "Effective uid=%s, gid=%s, home=%s",
dec2str(geteuid()), dec2str(getegid()), home);
if (*priv->chroot != '\0')
str_printfa(str, ", chroot=%s", priv->chroot);
i_debug("%s", str_c(str));
}
if ((user->flags & MAIL_STORAGE_SERVICE_FLAG_TEMP_PRIV_DROP) != 0 &&
(user->flags & MAIL_STORAGE_SERVICE_FLAG_ENABLE_CORE_DUMPS) == 0) {
/* we don't want to write core files to any users' home
directories since they could contain information about other
users' mails as well. so do no chdiring to home. */
} else if ((user->flags & MAIL_STORAGE_SERVICE_FLAG_NO_CHDIR) == 0) {
/* If possible chdir to home directory, so that core file
could be written in case we crash.
fallback to chdir()ing to root directory. this is needed
because the current directory may not be accessible after
dropping privileges, and for example unlink_directory()
requires ability to open the current directory. */
const char *chdir_path = user->chdir_path != NULL ?
user->chdir_path : home;
if (chdir_path[0] == '\0') {
if (chdir("/") < 0)
i_error("chdir(/) failed: %m");
} else if (chdir(chdir_path) < 0) {
if (errno == EACCES) {
i_error("%s", eacces_error_get("chdir",
t_strconcat(chdir_path, "/", NULL)));
} else if (errno != ENOENT)
i_error("chdir(%s) failed: %m", chdir_path);
else if (mail_set->mail_debug)
i_debug("Home dir not found: %s", chdir_path);
if (chdir("/") < 0)
i_error("chdir(/) failed: %m");
}
}
if (mail_user_init(mail_user, error_r) < 0) {
mail_user_unref(&mail_user);
return -1;
}
if ((user->flags & MAIL_STORAGE_SERVICE_FLAG_NO_NAMESPACES) == 0) {
if (mail_namespaces_init(mail_user, error_r) < 0) {
mail_user_unref(&mail_user);
return -1;
}
}
*mail_user_r = mail_user;
return 0;
}
void mail_storage_service_io_activate_user(struct mail_storage_service_user *user)
{
i_set_failure_prefix("%s", user->log_prefix);
}
void mail_storage_service_io_deactivate_user(struct mail_storage_service_user *user)
{
i_set_failure_prefix("%s", user->service_ctx->default_log_prefix);
}
void mail_storage_service_io_deactivate(struct mail_storage_service_ctx *ctx)
{
i_set_failure_prefix("%s", ctx->default_log_prefix);
}
static const char *field_get_default(const char *data)
{
const char *p;
p = strchr(data, ':');
if (p == NULL)
return "";
else {
/* default value given */
return p+1;
}
}
const char *mail_storage_service_fields_var_expand(const char *data,
const char *const *fields)
{
const char *field_name = t_strcut(data, ':');
unsigned int i;
size_t field_name_len;
if (fields == NULL)
return field_get_default(data);
field_name_len = strlen(field_name);
for (i = 0; fields[i] != NULL; i++) {
if (strncmp(fields[i], field_name, field_name_len) == 0 &&
fields[i][field_name_len] == '=')
return fields[i] + field_name_len+1;
}
return field_get_default(data);
}
static int
mail_storage_service_input_var_userdb(const char *data, void *context,
const char **value_r,
const char **error_r ATTR_UNUSED)
{
struct mail_storage_service_user *user = context;
*value_r = mail_storage_service_fields_var_expand(data,
user == NULL ? NULL : user->input.userdb_fields);
return 1;
}
static int
mail_storage_service_var_expand(struct mail_storage_service_ctx *ctx,
string_t *str, const char *format,
struct mail_storage_service_user *user,
const struct mail_storage_service_input *input,
const struct mail_storage_service_privileges *priv,
const char **error_r)
{
static const struct var_expand_func_table func_table[] = {
{ "userdb", mail_storage_service_input_var_userdb },
{ NULL, NULL }
};
return var_expand_with_funcs(str, format,
get_var_expand_table(ctx->service, user, input, priv),
func_table, user, error_r);
}
static void
mail_storage_service_init_log(struct mail_storage_service_ctx *ctx,
struct mail_storage_service_user *user,
struct mail_storage_service_privileges *priv)
{
const char *error;
ctx->log_initialized = TRUE;
T_BEGIN {
string_t *str;
str = t_str_new(256);
(void)mail_storage_service_var_expand(ctx, str,
user->user_set->mail_log_prefix,
user, &user->input, priv, &error);
user->log_prefix = p_strdup(user->pool, str_c(str));
} T_END;
master_service_init_log(ctx->service, user->log_prefix);
if (master_service_get_client_limit(master_service) == 1)
i_set_failure_send_prefix(user->log_prefix);
io_loop_context_add_callbacks(user->ioloop_ctx,
mail_storage_service_io_activate_user,
mail_storage_service_io_deactivate_user,
user);
}
static void mail_storage_service_time_moved(time_t old_time, time_t new_time)
{
long diff = new_time - old_time;
if (diff > 0) {
if (diff > MAX_NOWARN_FORWARD_SECS)
i_warning("Time jumped forwards %ld seconds", diff);
return;
}
diff = -diff;
if (diff > MAX_TIME_BACKWARDS_SLEEP) {
i_fatal("Time just moved backwards by %ld seconds. "
"This might cause a lot of problems, "
"so I'll just kill myself now. "
"http://wiki2.dovecot.org/TimeMovedBackwards", diff);
} else {
i_error("Time just moved backwards by %ld seconds. "
"I'll sleep now until we're back in present. "
"http://wiki2.dovecot.org/TimeMovedBackwards", diff);
/* Sleep extra second to make sure usecs also grows. */
diff++;
while (diff > 0 && sleep(diff) != 0) {
/* don't use sleep()'s return value, because
it could get us to a long loop in case
interrupts just keep coming */
diff = old_time - time(NULL) + 1;
}
}
}
struct mail_storage_service_ctx *
mail_storage_service_init(struct master_service *service,
const struct setting_parser_info *set_roots[],
enum mail_storage_service_flags flags)
{
struct mail_storage_service_ctx *ctx;
const char *version;
pool_t pool;
unsigned int count;
version = master_service_get_version_string(service);
if (version != NULL && strcmp(version, PACKAGE_VERSION) != 0) {
i_fatal("Version mismatch: libdovecot-storage.so is '%s', "
"while the running Dovecot binary is '%s'",
PACKAGE_VERSION, version);
}
if ((flags & MAIL_STORAGE_SERVICE_FLAG_TEMP_PRIV_DROP) != 0 &&
getuid() != 0) {
/* service { user } isn't root. the permission drop can't be
temporary. */
flags &= ~MAIL_STORAGE_SERVICE_FLAG_TEMP_PRIV_DROP;
}
(void)umask(0077);
io_loop_set_time_moved_callback(current_ioloop,
mail_storage_service_time_moved);
mail_storage_init();
pool = pool_alloconly_create("mail storage service", 2048);
ctx = p_new(pool, struct mail_storage_service_ctx, 1);
ctx->pool = pool;
ctx->service = service;
ctx->flags = flags;
/* @UNSAFE */
if (set_roots == NULL)
count = 0;
else
for (count = 0; set_roots[count] != NULL; count++) ;
ctx->set_roots =
p_new(pool, const struct setting_parser_info *, count + 2);
ctx->set_roots[0] = &mail_user_setting_parser_info;
if (set_roots != NULL) {
memcpy(ctx->set_roots + 1, set_roots,
sizeof(*ctx->set_roots) * count);
}
/* do all the global initialization. delay initializing plugins until
we drop privileges the first time. */
if ((flags & MAIL_STORAGE_SERVICE_FLAG_NO_LOG_INIT) == 0) {
/* note: we may not have read any settings yet, so this logging
may still be going to wrong location */
ctx->default_log_prefix =
p_strconcat(pool, service->name, ": ", NULL);
master_service_init_log(service, ctx->default_log_prefix);
}
dict_drivers_register_builtin();
return ctx;
}
struct auth_master_connection *
mail_storage_service_get_auth_conn(struct mail_storage_service_ctx *ctx)
{
i_assert(ctx->conn != NULL);
return ctx->conn;
}
static enum mail_storage_service_flags
mail_storage_service_input_get_flags(struct mail_storage_service_ctx *ctx,
const struct mail_storage_service_input *input)
{
enum mail_storage_service_flags flags;
flags = (ctx->flags & ~input->flags_override_remove) |
input->flags_override_add;
if (input->no_userdb_lookup) {
/* FIXME: for API backwards compatibility only */
flags &= ~MAIL_STORAGE_SERVICE_FLAG_USERDB_LOOKUP;
}
return flags;
}
int mail_storage_service_read_settings(struct mail_storage_service_ctx *ctx,
const struct mail_storage_service_input *input,
pool_t pool,
const struct setting_parser_info **user_info_r,
const struct setting_parser_context **parser_r,
const char **error_r)
{
struct master_service_settings_input set_input;