src/login-common/access-lookup.c

	access-lookup.c revision 2454dfa32c93c20a8522c6ed42fe057baaac9f9a
/* Copyright (c) 2010-2017 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "ioloop.h"
#include "net.h"
#include "fdpass.h"
#include "access-lookup.h"

#include <unistd.h>

#define ACCESS_LOOKUP_TIMEOUT_MSECS (1000*60)

struct access_lookup {
    int refcount;

    int fd;
    char *path;

    struct io *io;
    struct timeout *to;

    access_lookup_callback_t *callback;
    void *context;
};

static void access_lookup_input(struct access_lookup *lookup)
{
    unsigned char buf[3];
    ssize_t ret;
    bool success = FALSE;

    ret = read(lookup->fd, buf, sizeof(buf));
    if (ret < 0) {
        i_error("read(%s) failed: %m", lookup->path);
    } else if (ret == 0) {
        /* connection close -> no success */
    } else if (ret == 2 && buf[0] == '0' && buf[1] == '\n') {
        /* no success */
    } else if (ret == 2 && buf[0] == '1' && buf[1] == '\n') {
        success = TRUE;
    } else {
        i_error("access(%s): Invalid input", lookup->path);
    }

    lookup->refcount++;
    lookup->callback(success, lookup->context);
    if (lookup->refcount > 1)
        access_lookup_destroy(&lookup);
    access_lookup_destroy(&lookup);
}

static void access_lookup_timeout(struct access_lookup *lookup)
{
    i_error("access(%s): Timed out while waiting for reply", lookup->path);

    lookup->refcount++;
    lookup->callback(FALSE, lookup->context);
    if (lookup->refcount > 1)
        access_lookup_destroy(&lookup);
    access_lookup_destroy(&lookup);
}

struct access_lookup *
access_lookup(const char *path, int client_fd, const char *daemon_name,
          access_lookup_callback_t *callback, void *context)
{
    struct access_lookup *lookup;
    const char *cmd;
    ssize_t ret;
    int fd;

    fd = net_connect_unix(path);
    if (fd == -1) {
        i_error("connect(%s) failed: %m", path);
        return NULL;
    }

    cmd = t_strconcat(daemon_name, "\n", NULL);
    ret = fd_send(fd, client_fd, cmd, strlen(cmd));
    if (ret != (ssize_t)strlen(cmd)) {
        if (ret < 0)
            i_error("fd_send(%s) failed: %m", path);
        else
            i_error("fd_send(%s) didn't write enough bytes", path);
        i_close_fd(&fd);
        return NULL;
    }

    lookup = i_new(struct access_lookup, 1);
    lookup->refcount = 1;
    lookup->fd = fd;
    lookup->path = i_strdup(path);
    lookup->io = io_add(fd, IO_READ, access_lookup_input, lookup);
    lookup->to = timeout_add(ACCESS_LOOKUP_TIMEOUT_MSECS,
                 access_lookup_timeout, lookup);
    lookup->callback = callback;
    lookup->context = context;
    return lookup;
}

void access_lookup_destroy(struct access_lookup **_lookup)
{
    struct access_lookup *lookup = *_lookup;

    i_assert(lookup->refcount > 0);
    if (--lookup->refcount > 0)
        return;

    *_lookup = NULL;

    if (lookup->to != NULL)
        timeout_remove(&lookup->to);
    io_remove(&lookup->io);
    if (close(lookup->fd) < 0)
        i_error("close(%s) failed: %m", lookup->path);

    i_free(lookup->path);
    i_free(lookup);
}