src/lib-storage/mail-user.c

	mail-user.c revision 527c2b071dca35b91648344e867ab1af9c988281
/* Copyright (c) 2008-2016 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "array.h"
#include "hostpid.h"
#include "net.h"
#include "module-dir.h"
#include "home-expand.h"
#include "safe-mkstemp.h"
#include "str.h"
#include "strescape.h"
#include "var-expand.h"
#include "settings-parser.h"
#include "iostream-ssl.h"
#include "fs-api.h"
#include "auth-master.h"
#include "master-service.h"
#include "dict.h"
#include "mail-storage-settings.h"
#include "mail-storage-private.h"
#include "mail-storage-service.h"
#include "mail-namespace.h"
#include "mail-storage.h"
#include "mail-autoexpunge.h"
#include "mail-user.h"


struct mail_user_module_register mail_user_module_register = { 0 };
struct auth_master_connection *mail_user_auth_master_conn;

static void mail_user_deinit_base(struct mail_user *user)
{
    if (user->_attr_dict != NULL) {
        (void)dict_wait(user->_attr_dict);
        dict_deinit(&user->_attr_dict);
    }
    mail_namespaces_deinit(&user->namespaces);
}

static void mail_user_stats_fill_base(struct mail_user *user ATTR_UNUSED,
                      struct stats *stats ATTR_UNUSED)
{
}

struct mail_user *mail_user_alloc(const char *username,
                  const struct setting_parser_info *set_info,
                  const struct mail_user_settings *set)
{
    struct mail_user *user;
    const char *error;
    pool_t pool;

    i_assert(username != NULL);
    i_assert(*username != '\0');

    pool = pool_alloconly_create(MEMPOOL_GROWING"mail user", 16*1024);
    user = p_new(pool, struct mail_user, 1);
    user->pool = pool;
    user->refcount = 1;
    user->username = p_strdup(pool, username);
    user->set_info = set_info;
    user->unexpanded_set = settings_dup(set_info, set, pool);
    user->set = settings_dup(set_info, set, pool);
    user->service = master_service_get_name(master_service);
    user->default_normalizer = uni_utf8_to_decomposed_titlecase;

    /* check settings so that the duplicated structure will again
       contain the parsed fields */
    if (!settings_check(set_info, pool, user->set, &error))
        i_panic("Settings check unexpectedly failed: %s", error);

    user->v.deinit = mail_user_deinit_base;
    user->v.stats_fill = mail_user_stats_fill_base;
    p_array_init(&user->module_contexts, user->pool, 5);
    return user;
}

static void
mail_user_expand_plugins_envs(struct mail_user *user)
{
    const char **envs, *home;
    string_t *str;
    unsigned int i, count;

    if (!array_is_created(&user->set->plugin_envs))
        return;

    str = t_str_new(256);
    envs = array_get_modifiable(&user->set->plugin_envs, &count);
    i_assert((count % 2) == 0);
    for (i = 0; i < count; i += 2) {
        if (user->_home == NULL &&
            var_has_key(envs[i+1], 'h', "home") &&
            mail_user_get_home(user, &home) <= 0) {
            user->error = p_strdup_printf(user->pool,
                "userdb didn't return a home directory, "
                "but plugin setting %s used it (%%h): %s",
                envs[i], envs[i+1]);
            return;
        }
        str_truncate(str, 0);
        var_expand_with_funcs(str, envs[i+1],
                      mail_user_var_expand_table(user),
                      mail_user_var_expand_func_table, user);
        envs[i+1] = p_strdup(user->pool, str_c(str));
    }
}

int mail_user_init(struct mail_user *user, const char **error_r)
{
    const struct mail_storage_settings *mail_set;
    const char *home, *key, *value;
    bool need_home_dir;

    need_home_dir = user->_home == NULL &&
        settings_vars_have_key(user->set_info, user->set,
                       'h', "home", &key, &value);
    if (need_home_dir && mail_user_get_home(user, &home) <= 0) {
        user->error = p_strdup_printf(user->pool,
            "userdb didn't return a home directory, "
            "but %s used it (%%h): %s", key, value);
    }

    /* expand settings after we can expand %h */
    settings_var_expand_with_funcs(user->set_info, user->set,
                       user->pool, mail_user_var_expand_table(user),
                       mail_user_var_expand_func_table, user);
    user->settings_expanded = TRUE;
    mail_user_expand_plugins_envs(user);

    /* autocreated users for shared mailboxes need to be fully initialized
       if they don't exist, since they're going to be used anyway */
    if (user->error == NULL || user->nonexistent) {
        mail_set = mail_user_set_get_storage_set(user);
        user->mail_debug = mail_set->mail_debug;

        user->initialized = TRUE;
        hook_mail_user_created(user);
    }

    if (user->error != NULL) {
        *error_r = t_strdup(user->error);
        return -1;
    }
    return 0;
}

void mail_user_ref(struct mail_user *user)
{
    i_assert(user->refcount > 0);

    user->refcount++;
}

void mail_user_unref(struct mail_user **_user)
{
    struct mail_user *user = *_user;

    i_assert(user->refcount > 0);

    *_user = NULL;
    if (user->refcount > 1) {
        user->refcount--;
        return;
    }

    if (user->autoexpunge_enabled)
        mail_user_autoexpunge(user);

    user->deinitializing = TRUE;

    /* call deinit() with refcount=1, otherwise we may assert-crash in
       mail_user_ref() that is called by some deinit() handler. */
    user->v.deinit(user);
    i_assert(user->refcount == 1);
    pool_unref(&user->pool);
}

struct mail_user *mail_user_find(struct mail_user *user, const char *name)
{
    struct mail_namespace *ns;

    for (ns = user->namespaces; ns != NULL; ns = ns->next) {
        if (ns->owner != NULL && strcmp(ns->owner->username, name) == 0)
            return ns->owner;
    }
    return NULL;
}

void mail_user_set_vars(struct mail_user *user, const char *service,
            const struct ip_addr *local_ip,
            const struct ip_addr *remote_ip)
{
    i_assert(service != NULL);

    user->service = p_strdup(user->pool, service);
    if (local_ip != NULL && local_ip->family != 0) {
        user->local_ip = p_new(user->pool, struct ip_addr, 1);
        *user->local_ip = *local_ip;
    }
    if (remote_ip != NULL && remote_ip->family != 0) {
        user->remote_ip = p_new(user->pool, struct ip_addr, 1);
        *user->remote_ip = *remote_ip;
    }
}

const struct var_expand_table *
mail_user_var_expand_table(struct mail_user *user)
{
    static struct var_expand_table static_tab[] = {
        { 'u', NULL, "user" },
        { 'n', NULL, "username" },
        { 'd', NULL, "domain" },
        { 's', NULL, "service" },
        { 'h', NULL, "home" },
        { 'l', NULL, "lip" },
        { 'r', NULL, "rip" },
        { 'p', NULL, "pid" },
        { 'i', NULL, "uid" },
        { '\0', NULL, "gid" },
        { '\0', NULL, "session" },
        { '\0', NULL, "auth_user" },
        { '\0', NULL, "auth_username" },
        { '\0', NULL, "auth_domain" },
        /* NOTE: keep this synced with imap-hibernate's
           imap_client_var_expand_table() */
        { '\0', NULL, NULL }
    };
    struct var_expand_table *tab;

    /* use a cached table, unless home directory has been set afterwards */
    if (user->var_expand_table != NULL &&
        user->var_expand_table[4].value == user->_home)
        return user->var_expand_table;

    tab = p_malloc(user->pool, sizeof(static_tab));
    memcpy(tab, static_tab, sizeof(static_tab));

    tab[0].value = user->username;
    tab[1].value = p_strdup(user->pool, t_strcut(user->username, '@'));
    tab[2].value = strchr(user->username, '@');
    if (tab[2].value != NULL) tab[2].value++;
    tab[3].value = user->service;
    tab[4].value = user->_home; /* don't look it up unless we need it */
    tab[5].value = user->local_ip == NULL ? NULL :
        p_strdup(user->pool, net_ip2addr(user->local_ip));
    tab[6].value = user->remote_ip == NULL ? NULL :
        p_strdup(user->pool, net_ip2addr(user->remote_ip));
    tab[7].value = my_pid;
    tab[8].value = p_strdup(user->pool, dec2str(user->uid));
    tab[9].value = p_strdup(user->pool, dec2str(user->gid));
    tab[10].value = user->session_id;
    if (user->auth_user == NULL) {
        tab[11].value = tab[0].value;
        tab[12].value = tab[1].value;
        tab[13].value = tab[2].value;
    } else {
        tab[11].value = user->auth_user;
        tab[12].value = p_strdup(user->pool, t_strcut(user->auth_user, '@'));
        tab[13].value = strchr(user->auth_user, '@');
    }

    user->var_expand_table = tab;
    return user->var_expand_table;
}

static const char *
mail_user_var_expand_func_userdb(const char *data, void *context)
{
    struct mail_user *user = context;

    return mail_storage_service_fields_var_expand(data, user->userdb_fields);
}

void mail_user_set_home(struct mail_user *user, const char *home)
{
    user->_home = p_strdup(user->pool, home);
    user->home_looked_up = TRUE;
}

void mail_user_add_namespace(struct mail_user *user,
                 struct mail_namespace **namespaces)
{
    struct mail_namespace **tmp, *next, *ns = *namespaces;

    for (; ns != NULL; ns = next) {
        next = ns->next;

        tmp = &user->namespaces;
        for (; *tmp != NULL; tmp = &(*tmp)->next) {
            i_assert(*tmp != ns);
            if (strlen(ns->prefix) < strlen((*tmp)->prefix))
                break;
        }
        ns->next = *tmp;
        *tmp = ns;
    }
    *namespaces = user->namespaces;

    T_BEGIN {
        hook_mail_namespaces_added(user->namespaces);
    } T_END;
}

void mail_user_drop_useless_namespaces(struct mail_user *user)
{
    struct mail_namespace *ns, *next;

    /* drop all autocreated unusable (typically shared) namespaces.
       don't drop the autocreated prefix="" namespace that we explicitly
       created for being the fallback namespace. */
    for (ns = user->namespaces; ns != NULL; ns = next) {
        next = ns->next;

        if ((ns->flags & NAMESPACE_FLAG_USABLE) == 0 &&
            (ns->flags & NAMESPACE_FLAG_AUTOCREATED) != 0 &&
            ns->prefix_len > 0)
            mail_namespace_destroy(ns);
    }
}

const char *mail_user_home_expand(struct mail_user *user, const char *path)
{
    (void)mail_user_try_home_expand(user, &path);
    return path;
}

static int mail_user_userdb_lookup_home(struct mail_user *user)
{
    struct auth_user_info info;
    struct auth_user_reply reply;
    pool_t userdb_pool;
    const char *username, *const *fields;
    int ret;

    i_assert(!user->home_looked_up);

    memset(&info, 0, sizeof(info));
    info.service = user->service;
    if (user->local_ip != NULL)
        info.local_ip = *user->local_ip;
    if (user->remote_ip != NULL)
        info.remote_ip = *user->remote_ip;

    userdb_pool = pool_alloconly_create("userdb lookup", 2048);
    ret = auth_master_user_lookup(mail_user_auth_master_conn,
                      user->username, &info, userdb_pool,
                      &username, &fields);
    if (ret > 0) {
        auth_user_fields_parse(fields, userdb_pool, &reply);
        user->_home = p_strdup(user->pool, reply.home);
    }
    pool_unref(&userdb_pool);
    return ret;
}

static void mail_user_get_mail_home(struct mail_user *user)
{
    const char *home = user->set->mail_home;
    string_t *str;

    if (user->settings_expanded) {
        user->_home = home[0] != '\0' ? home : NULL;
        return;
    }
    /* we're still initializing user. need to do the expansion ourself. */
    i_assert(home[0] == SETTING_STRVAR_UNEXPANDED[0]);
    home++;
    if (home[0] == '\0')
        return;

    str = t_str_new(128);
    var_expand_with_funcs(str, home,
                  mail_user_var_expand_table(user),
                  mail_user_var_expand_func_table, user);
    user->_home = p_strdup(user->pool, str_c(str));
}

int mail_user_get_home(struct mail_user *user, const char **home_r)
{
    int ret;

    if (user->home_looked_up) {
        *home_r = user->_home;
        return user->_home != NULL ? 1 : 0;
    }

    if (mail_user_auth_master_conn == NULL) {
        /* no userdb connection. we can only use mail_home setting. */
        mail_user_get_mail_home(user);
    } else if ((ret = mail_user_userdb_lookup_home(user)) < 0) {
        /* userdb lookup failed */
        return -1;
    } else if (ret == 0) {
        /* user doesn't exist */
        user->nonexistent = TRUE;
    } else if (user->_home == NULL) {
        /* no home returned by userdb lookup, fallback to
           mail_home setting. */
        mail_user_get_mail_home(user);
    }
    user->home_looked_up = TRUE;

    *home_r = user->_home;
    return user->_home != NULL ? 1 : 0;
}

bool mail_user_is_plugin_loaded(struct mail_user *user, struct module *module)
{
    const char *const *plugins;
    bool ret;

    T_BEGIN {
        plugins = t_strsplit_spaces(user->set->mail_plugins, ", ");
        ret = str_array_find(plugins, module_get_plugin_name(module));
    } T_END;
    return ret;
}

bool mail_user_plugin_getenv_bool(struct mail_user *user, const char *name)
{
    const char *env = mail_user_set_plugin_getenv(user->set, name);

    if (env == NULL)
        return FALSE;
    switch (env[0]) {
        case 'n':
        case 'N':
        case '0':
        case 'f':
        case 'F':
        return FALSE;
    }

    //any other value including empty string will be treated as TRUE.
    return TRUE;
}

const char *mail_user_plugin_getenv(struct mail_user *user, const char *name)
{
    return mail_user_set_plugin_getenv(user->set, name);
}

const char *mail_user_set_plugin_getenv(const struct mail_user_settings *set,
                    const char *name)
{
    const char *const *envs;
    unsigned int i, count;

    if (!array_is_created(&set->plugin_envs))
        return NULL;

    envs = array_get(&set->plugin_envs, &count);
    for (i = 0; i < count; i += 2) {
        if (strcmp(envs[i], name) == 0)
            return envs[i+1];
    }
    return NULL;
}

int mail_user_try_home_expand(struct mail_user *user, const char **pathp)
{
    const char *home, *path = *pathp;

    if (*path != '~') {
        /* no need to expand home */
        return 0;
    }

    if (mail_user_get_home(user, &home) <= 0)
        return -1;

    path = home_expand_tilde(path, home);
    if (path == NULL)
        return -1;

    *pathp = path;
    return 0;
}

void mail_user_set_get_temp_prefix(string_t *dest,
                   const struct mail_user_settings *set)
{
    str_append(dest, set->mail_temp_dir);
    str_append(dest, "/dovecot.");
    str_append(dest, master_service_get_name(master_service));
    str_append_c(dest, '.');
}

const char *mail_user_get_anvil_userip_ident(struct mail_user *user)
{
    if (user->remote_ip == NULL)
        return NULL;
    return t_strconcat(net_ip2addr(user->remote_ip), "/",
               str_tabescape(user->username), NULL);
}

static void
mail_user_try_load_class_plugin(struct mail_user *user, const char *name)
{
    struct module_dir_load_settings mod_set;
    struct module *module;
    unsigned int name_len = strlen(name);

    memset(&mod_set, 0, sizeof(mod_set));
    mod_set.abi_version = DOVECOT_ABI_VERSION;
    mod_set.binary_name = master_service_get_name(master_service);
    mod_set.setting_name = "<built-in storage lookup>";
    mod_set.require_init_funcs = TRUE;
    mod_set.debug = user->mail_debug;

    mail_storage_service_modules =
        module_dir_load_missing(mail_storage_service_modules,
                    user->set->mail_plugin_dir,
                    name, &mod_set);
    /* initialize the module (and only this module!) immediately so that
       the class gets registered */
    for (module = mail_storage_service_modules; module != NULL; module = module->next) {
        if (strncmp(module->name, name, name_len) == 0 &&
            strcmp(module->name + name_len, "_plugin") == 0) {
            if (!module->initialized) {
                module->initialized = TRUE;
                module->init(module);
            }
            break;
        }
    }
}

struct mail_storage *
mail_user_get_storage_class(struct mail_user *user, const char *name)
{
    struct mail_storage *storage;

    storage = mail_storage_find_class(name);
    if (storage == NULL || storage->v.alloc != NULL)
        return storage;

    /* it's implemented by a plugin. load it and check again. */
    mail_user_try_load_class_plugin(user, name);

    storage = mail_storage_find_class(name);
    if (storage != NULL && storage->v.alloc == NULL) {
        i_error("Storage driver '%s' exists as a stub, "
            "but its plugin couldn't be loaded", name);
        return NULL;
    }
    return storage;
}

struct mail_user *mail_user_dup(struct mail_user *user)
{
    struct mail_user *user2;

    user2 = mail_user_alloc(user->username, user->set_info,
                user->unexpanded_set);
    user2->_service_user = user->_service_user;
    if (user->_home != NULL)
        mail_user_set_home(user2, user->_home);
    mail_user_set_vars(user2, user->service,
               user->local_ip, user->remote_ip);
    user2->uid = user->uid;
    user2->gid = user->gid;
    user2->anonymous = user->anonymous;
    user2->admin = user->admin;
    user2->auth_token = p_strdup(user2->pool, user->auth_token);
    user2->auth_user = p_strdup(user2->pool, user->auth_user);
    user2->session_id = p_strdup(user2->pool, user->session_id);
    return user2;
}

void mail_user_init_fs_settings(struct mail_user *user,
                struct fs_settings *fs_set,
                struct ssl_iostream_settings *ssl_set)
{
    const struct mail_storage_settings *mail_set =
        mail_user_set_get_storage_set(user);

    fs_set->username = user->username;
    fs_set->session_id = user->session_id;
    fs_set->base_dir = user->set->base_dir;
    fs_set->temp_dir = user->set->mail_temp_dir;
    fs_set->debug = user->mail_debug;
    fs_set->enable_timing = user->stats_enabled;

    fs_set->ssl_client_set = ssl_set;
    ssl_set->ca_dir = mail_set->ssl_client_ca_dir;
    ssl_set->ca_file = mail_set->ssl_client_ca_file;
}

void mail_user_stats_fill(struct mail_user *user, struct stats *stats)
{
    user->v.stats_fill(user, stats);
}

static const struct var_expand_func_table mail_user_var_expand_func_table_arr[] = {
    { "userdb", mail_user_var_expand_func_userdb },
    { NULL, NULL }
};
const struct var_expand_func_table *mail_user_var_expand_func_table =
    mail_user_var_expand_func_table_arr;