src/director/auth-connection.c

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

#include "lib.h"
#include "ioloop.h"
#include "istream.h"
#include "ostream.h"
#include "net.h"
#include "llist.h"
#include "safe-memset.h"
#include "auth-client-interface.h"
#include "auth-connection.h"

#include <unistd.h>

struct auth_connection {
    struct auth_connection *prev, *next;

    char *path;
    int fd;
    struct io *io;
    struct istream *input;
    struct ostream *output;

    auth_input_callback *callback;
    void *context;
};

static struct auth_connection *auth_connections;

static void auth_connection_disconnected(struct auth_connection **conn);

static void auth_connection_input(struct auth_connection *conn)
{
    char *line;

    switch (i_stream_read(conn->input)) {
    case 0:
        return;
    case -1:
        /* disconnected */
        i_error("Auth server disconnected unexpectedly");
        auth_connection_disconnected(&conn);
        return;
    case -2:
        /* buffer full */
        i_error("BUG: Auth server sent us more than %d bytes",
            (int)AUTH_CLIENT_MAX_LINE_LENGTH);
        auth_connection_disconnected(&conn);
        return;
    }

    while ((line = i_stream_next_line(conn->input)) != NULL) {
        T_BEGIN {
            conn->callback(line, conn->context);
            safe_memset(line, 0, strlen(line));
        } T_END;
    }
}

struct auth_connection *auth_connection_init(const char *path)
{
    struct auth_connection *conn;

    conn = i_new(struct auth_connection, 1);
    conn->fd = -1;
    conn->path = i_strdup(path);
    DLLIST_PREPEND(&auth_connections, conn);
    return conn;
}

void auth_connection_set_callback(struct auth_connection *conn,
                  auth_input_callback *callback, void *context)
{
    conn->callback = callback;
    conn->context = context;
}

int auth_connection_connect(struct auth_connection *conn)
{
    i_assert(conn->fd == -1);

    conn->fd = net_connect_unix_with_retries(conn->path, 1000);
    if (conn->fd == -1) {
        i_error("connect(%s) failed: %m", conn->path);
        return -1;
    }

    conn->input = i_stream_create_fd(conn->fd, AUTH_CLIENT_MAX_LINE_LENGTH);
    conn->output = o_stream_create_fd(conn->fd, (size_t)-1);
    o_stream_set_no_error_handling(conn->output, TRUE);
    conn->io = io_add(conn->fd, IO_READ, auth_connection_input, conn);
    return 0;
}

void auth_connection_deinit(struct auth_connection **_conn)
{
    struct auth_connection *conn = *_conn;

    *_conn = NULL;

    DLLIST_REMOVE(&auth_connections, conn);
    if (conn->fd != -1) {
        io_remove(&conn->io);
        i_stream_unref(&conn->input);
        o_stream_unref(&conn->output);

        if (close(conn->fd) < 0)
            i_error("close(auth connection) failed: %m");
    }
    i_free(conn->path);
    i_free(conn);
}

static void auth_connection_disconnected(struct auth_connection **_conn)
{
    struct auth_connection *conn = *_conn;

    *_conn = NULL;
    /* notify callback. it should deinit this connection */
    conn->callback(NULL, conn->context);
}

struct ostream *auth_connection_get_output(struct auth_connection *conn)
{
    i_assert(conn->output != NULL);
    return conn->output;
}

void auth_connections_deinit(void)
{
    while (auth_connections != NULL) {
        struct auth_connection *conn = auth_connections;

        auth_connection_disconnected(&conn);
    }
}