src/doveadm/doveadm-mail-server.c

/* Copyright (c) 2010-2018 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "array.h"
#include "hash.h"
#include "str.h"
#include "strescape.h"
#include "ioloop.h"
#include "master-service.h"
#include "auth-master.h"
#include "mail-storage.h"
#include "mail-storage-service.h"
#include "server-connection.h"
#include "doveadm-settings.h"
#include "doveadm-print.h"
#include "doveadm-server.h"
#include "doveadm-mail.h"

#define DOVEADM_SERVER_CONNECTIONS_MAX 4
#define DOVEADM_SERVER_QUEUE_MAX 16

#define DOVEADM_MAIL_SERVER_FAILED() \
    (internal_failure || master_service_is_killed(master_service))

struct doveadm_mail_server_cmd {
    struct server_connection *conn;
    char *username;
};

static HASH_TABLE(char *, struct doveadm_server *) servers;
static pool_t server_pool;
static struct doveadm_mail_cmd_context *cmd_ctx;
static bool internal_failure = FALSE;

static void doveadm_mail_server_handle(struct server_connection *conn,
                       const char *username);

static struct doveadm_server *
doveadm_server_get(struct doveadm_mail_cmd_context *ctx, const char *name)
{
    struct doveadm_server *server;
    const char *p;
    char *dup_name;

    if (!hash_table_is_created(servers)) {
        server_pool = pool_alloconly_create("doveadm servers", 1024*16);
        hash_table_create(&servers, server_pool, 0, str_hash, strcmp);
    }
    server = hash_table_lookup(servers, name);
    if (server == NULL) {
        server = p_new(server_pool, struct doveadm_server, 1);
        server->name = dup_name = p_strdup(server_pool, name);
        p = strrchr(server->name, ':');
        server->hostname = p == NULL ? server->name :
            p_strdup_until(server_pool, server->name, p);

        p_array_init(&server->connections, server_pool,
                 ctx->set->doveadm_worker_count);
        p_array_init(&server->queue, server_pool,
                 DOVEADM_SERVER_QUEUE_MAX);
        hash_table_insert(servers, dup_name, server);
    }
    return server;
}

static struct server_connection *
doveadm_server_find_unused_conn(struct doveadm_server *server)
{
    struct server_connection *const *connp;

    array_foreach(&server->connections, connp) {
        if (server_connection_is_idle(*connp))
            return *connp;
    }
    return NULL;
}

static bool doveadm_server_have_used_connections(struct doveadm_server *server)
{
    struct server_connection *const *connp;

    array_foreach(&server->connections, connp) {
        if (!server_connection_is_idle(*connp))
            return TRUE;
    }
    return FALSE;
}

static void doveadm_cmd_callback(int exit_code, const char *error,
                 void *context)
{
    struct doveadm_mail_server_cmd *servercmd = context;
    struct doveadm_server *server =
        server_connection_get_server(servercmd->conn);
    const char *username = t_strdup(servercmd->username);

    i_free(servercmd->username);
    i_free(servercmd);

    switch (exit_code) {
    case 0:
        break;
    case SERVER_EXIT_CODE_DISCONNECTED:
        i_error("%s: Command %s failed for %s: %s",
            server->name, cmd_ctx->cmd->name, username, error);
        internal_failure = TRUE;
        io_loop_stop(current_ioloop);
        return;
    case EX_NOUSER:
        i_error("%s: No such user: %s", server->name, username);
        if (cmd_ctx->exit_code == 0)
            cmd_ctx->exit_code = EX_NOUSER;
        break;
    default:
        if (cmd_ctx->exit_code == 0 || exit_code == EX_TEMPFAIL)
            cmd_ctx->exit_code = exit_code;
        break;
    }

    if (array_count(&server->queue) > 0) {
        struct server_connection *conn;
        char *const *usernamep = array_idx(&server->queue, 0);
        char *username = *usernamep;

        conn = doveadm_server_find_unused_conn(server);
        if (conn != NULL) {
            array_delete(&server->queue, 0, 1);
            doveadm_mail_server_handle(conn, username);
            i_free(username);
        }
    }

    io_loop_stop(current_ioloop);
}

static void doveadm_mail_server_handle(struct server_connection *conn,
                       const char *username)
{
    struct doveadm_mail_server_cmd *servercmd;
    string_t *cmd;
    unsigned int i;

    /* <flags> <username> <command> [<args>] */
    cmd = t_str_new(256);
    if (doveadm_debug)
        str_append_c(cmd, 'D');
    else if (doveadm_verbose)
        str_append_c(cmd, 'v');
    str_append_c(cmd, '\t');

    str_append_tabescaped(cmd, username);
    str_append_c(cmd, '\t');
    str_append_tabescaped(cmd, cmd_ctx->cmd->name);
    for (i = 0; cmd_ctx->full_args[i] != NULL; i++) {
        str_append_c(cmd, '\t');
        str_append_tabescaped(cmd, cmd_ctx->full_args[i]);
    }
    str_append_c(cmd, '\n');

    servercmd = i_new(struct doveadm_mail_server_cmd, 1);
    servercmd->conn = conn;
    servercmd->username = i_strdup(username);
    server_connection_cmd(conn, str_c(cmd), cmd_ctx->cmd_input,
                  doveadm_cmd_callback, servercmd);
}

static void doveadm_server_flush_one(struct doveadm_server *server)
{
    unsigned int count = array_count(&server->queue);

    do {
        io_loop_run(current_ioloop);
    } while (array_count(&server->queue) == count &&
         doveadm_server_have_used_connections(server) &&
         !DOVEADM_MAIL_SERVER_FAILED());
}

static int
doveadm_mail_server_user_get_host(struct doveadm_mail_cmd_context *ctx,
                  const struct mail_storage_service_input *input,
                  const char **user_r, const char **host_r,
                  const char **error_r)
{
    struct auth_master_connection *auth_conn;
    struct auth_user_info info;
    pool_t pool;
    const char *auth_socket_path, *proxy_host, *proxy_hostip, *const *fields;
    unsigned int i;
    in_port_t proxy_port;
    bool proxying;
    int ret;

    *user_r = input->username;
    *host_r = ctx->set->doveadm_socket_path;

    if (ctx->set->doveadm_port == 0)
        return 0;

    /* make sure we have an auth connection */
    mail_storage_service_init_settings(ctx->storage_service, input);

    i_zero(&info);
    info.service = master_service_get_name(master_service);
    info.local_ip = input->local_ip;
    info.remote_ip = input->remote_ip;
    info.local_port = input->local_port;
    info.remote_port = input->remote_port;

    pool = pool_alloconly_create("auth lookup", 1024);
    auth_conn = mail_storage_service_get_auth_conn(ctx->storage_service);
    auth_socket_path = auth_master_get_socket_path(auth_conn);
    ret = auth_master_pass_lookup(auth_conn, input->username, &info,
                      pool, &fields);
    if (ret < 0) {
        *error_r = fields[0] != NULL ?
            t_strdup(fields[0]) : "passdb lookup failed";
        *error_r = t_strdup_printf("%s: %s (to see if user is proxied, "
                       "because doveadm_port is set)",
                       auth_socket_path, *error_r);
    } else if (ret == 0) {
        /* user not found from passdb. it could be in userdb though,
           so just continue with the default host */
    } else {
        proxy_host = NULL; proxy_hostip = NULL; proxying = FALSE;
        proxy_port = ctx->set->doveadm_port;
        for (i = 0; fields[i] != NULL; i++) {
            if (strncmp(fields[i], "proxy", 5) == 0 &&
                (fields[i][5] == '\0' || fields[i][5] == '='))
                proxying = TRUE;
            else if (strncmp(fields[i], "host=", 5) == 0)
                proxy_host = fields[i]+5;
            else if (strncmp(fields[i], "hostip=", 7) == 0)
                proxy_hostip = fields[i]+7;
            else if (strncmp(fields[i], "user=", 5) == 0)
                *user_r = t_strdup(fields[i]+5);
            else if (strncmp(fields[i], "destuser=", 9) == 0)
                *user_r = t_strdup(fields[i]+9);
            else if (strncmp(fields[i], "port=", 5) == 0) {
                if (net_str2port(fields[i]+5, &proxy_port) < 0)
                    proxy_port = 0;
            }
        }
        if (proxy_hostip != NULL)
            proxy_host = proxy_hostip;
        if (!proxying)
            ret = 0;
        else if (proxy_host == NULL) {
            *error_r = t_strdup_printf("%s: Proxy is missing destination host",
                           auth_socket_path);
            if (strstr(auth_socket_path, "/auth-userdb") != NULL) {
                *error_r = t_strdup_printf(
                    "%s (maybe set auth_socket_path=director-userdb)",
                    *error_r);
            }
            ret = -1;
        } else {
            *host_r = t_strdup_printf("%s:%u", proxy_host, proxy_port);
        }
    }
    pool_unref(&pool);
    return ret;
}

int doveadm_mail_server_user(struct doveadm_mail_cmd_context *ctx,
                 const struct mail_storage_service_input *input,
                 const char **error_r)
{
    struct doveadm_server *server;
    struct server_connection *conn;
    const char *user, *host;
    char *username_dup;
    int ret;

    i_assert(cmd_ctx == ctx || cmd_ctx == NULL);
    cmd_ctx = ctx;

    ret = doveadm_mail_server_user_get_host(ctx, input, &user, &host, error_r);
    if (ret < 0)
        return ret;
    if (ret == 0 &&
        (ctx->set->doveadm_worker_count == 0 || doveadm_server)) {
        /* run it ourself */
        return 0;
    }

    /* server sends the sticky headers for each row as well,
       so undo any sticks we might have added already */
    doveadm_print_unstick_headers();

    server = doveadm_server_get(ctx, host);
    conn = doveadm_server_find_unused_conn(server);
    if (conn != NULL)
        doveadm_mail_server_handle(conn, user);
    else if (array_count(&server->connections) <
            I_MAX(ctx->set->doveadm_worker_count, 1)) {
        if (server_connection_create(server, &conn) < 0)
            internal_failure = TRUE;
        else
            doveadm_mail_server_handle(conn, user);
    } else {
        if (array_count(&server->queue) >= DOVEADM_SERVER_QUEUE_MAX)
            doveadm_server_flush_one(server);

        username_dup = i_strdup(user);
        array_append(&server->queue, &username_dup, 1);
    }
    *error_r = "doveadm server failure";
    return DOVEADM_MAIL_SERVER_FAILED() ? -1 : 1;
}

static struct doveadm_server *doveadm_server_find_used(void)
{
    struct hash_iterate_context *iter;
    struct doveadm_server *ret = NULL;
    char *key;
    struct doveadm_server *server;

    iter = hash_table_iterate_init(servers);
    while (hash_table_iterate(iter, servers, &key, &server)) {
        if (doveadm_server_have_used_connections(server)) {
            ret = server;
            break;
        }
    }
    hash_table_iterate_deinit(&iter);
    return ret;
}

static void doveadm_servers_destroy_all_connections(void)
{
    struct hash_iterate_context *iter;
    char *key;
    struct doveadm_server *server;

    iter = hash_table_iterate_init(servers);
    while (hash_table_iterate(iter, servers, &key, &server)) {
        while (array_count(&server->connections) > 0) {
            struct server_connection *const *connp, *conn;

            connp = array_idx(&server->connections, 0);
            conn = *connp;
            server_connection_destroy(&conn);
        }
    }
    hash_table_iterate_deinit(&iter);
}

void doveadm_mail_server_flush(void)
{
    struct doveadm_server *server;

    if (!hash_table_is_created(servers)) {
        cmd_ctx = NULL;
        return;
    }

    while ((server = doveadm_server_find_used()) != NULL &&
           !DOVEADM_MAIL_SERVER_FAILED())
        doveadm_server_flush_one(server);

    doveadm_servers_destroy_all_connections();
    if (master_service_is_killed(master_service))
        i_error("Aborted");
    if (DOVEADM_MAIL_SERVER_FAILED())
        doveadm_mail_failed_error(cmd_ctx, MAIL_ERROR_TEMP);

    hash_table_destroy(&servers);
    pool_unref(&server_pool);
    cmd_ctx = NULL;
}