/* * ProFTPD - FTP server daemon * Copyright (c) 1997, 1998 Public Flood Software * Copyright (c) 1999, 2000 MacGyver aka Habeeb J. Dihu * Copyright (c) 2001, 2002, 2003 The ProFTPD Project * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. * * As a special exemption, Public Flood Software/MacGyver aka Habeeb J. Dihu * and other respective copyright holders give permission to link this program * with OpenSSL, and distribute the resulting executable, without including * the source code for OpenSSL in the source distribution. */ /* Network IO stream layer * $Id: netio.h,v 1.9 2004/10/09 20:46:21 castaglia Exp $ */ #ifndef PR_NETIO_H #define PR_NETIO_H /* Network I/O stream types */ /* This indicates that the netio being registered should be used when * performing network I/O for the control connection. */ #define PR_NETIO_STRM_CTRL 0x00010 /* This indicates that the netio being registered should be used when * performing network I/O for the data connection. */ #define PR_NETIO_STRM_DATA 0x00020 /* This indicates that the netio being registered should be used when * performing network I/O for other connections (e.g. RFC931 lookups). * This is rarely used. */ #define PR_NETIO_STRM_OTHR 0x00040 /* Network I/O stream direction */ #define PR_NETIO_IO_RD 1 #define PR_NETIO_IO_WR 2 /* Network I/O stream session flags */ /* This indicates that netio functions are allowed to be interruped by * EINTR, and to return -2. */ #define PR_NETIO_SESS_INTR (1 << 1) /* This is a temporary internal flag used to indicate that I/O on a * network stream has been aborted, and should return -2 at the next * possible instant. In combination with NETIO_INTR and interruptible * syscalls, this should be near instantly. This flag cannot be tested * for as it is cleared immediately after being detected. */ #define PR_NETIO_SESS_ABORT (1 << 2) /* Network I/O objects */ typedef struct { /* Pointer to the buffer memory. */ char *buf; /* Total length of the buffer. */ unsigned long buflen; /* Pointer to the current byte in the buffer. */ char *current; /* Number of bytes left in the buffer. */ int remaining; } pr_buffer_t; typedef struct { /* Memory pool for this object. */ pool *strm_pool; /* Stream type */ int strm_type; /* File descriptor for this I/O stream. */ int strm_fd; /* I/O mode: PR_NETIO_IO_RD or PR_NETIO_IO_WR. Patterned after * open(2). */ int strm_mode; /* Poll interval for this stream. */ unsigned int strm_interval; /* Internal use. */ volatile unsigned long strm_flags; /* Buffer. */ pr_buffer_t *strm_buf; /* Arbitrary data for outside use. */ void *strm_data; /* errno, if applicable. */ int strm_errno; } pr_netio_stream_t; #define PR_NETIO_ERRNO(s) ((s)->strm_errno) #define PR_NETIO_FD(s) ((s)->strm_fd) typedef struct { /* Memory pool for this object. */ pool *pool; /* NetIO callbacks */ void (*abort)(pr_netio_stream_t *); int (*close)(pr_netio_stream_t *); pr_netio_stream_t *(*open)(pr_netio_stream_t *, int, int); int (*poll)(pr_netio_stream_t *); int (*postopen)(pr_netio_stream_t *); int (*read)(pr_netio_stream_t *, char *, size_t); pr_netio_stream_t *(*reopen)(pr_netio_stream_t *, int, int); int (*shutdown)(pr_netio_stream_t *, int); int (*write)(pr_netio_stream_t *, char *, size_t); } pr_netio_t; /* Network IO function prototypes */ void pr_netio_abort(pr_netio_stream_t *); int pr_netio_lingering_abort(pr_netio_stream_t *, long); int pr_netio_close(pr_netio_stream_t *); int pr_netio_lingering_close(pr_netio_stream_t *, long); #define NETIO_LINGERING_CLOSE_FL_NO_SHUTDOWN 0x00001 char *pr_netio_gets(char *, size_t, pr_netio_stream_t *); pr_netio_stream_t *pr_netio_open(pool *, int, int, int); int pr_netio_postopen(pr_netio_stream_t *); int pr_netio_printf(pr_netio_stream_t *, const char *, ...); /* pr_netio_printf_async() is for use inside alarm handlers, where no * pr_netio_poll() blocking is allowed. This is necessary because otherwise, * pr_netio_poll() can potentially hang forever if the send queue is maxed and * the socket has been closed. */ int pr_netio_printf_async(pr_netio_stream_t *, char *,...); /* pr_netio_poll() is needed instead of simply blocking read/write because * there is a race condition if the syscall _should_ be interrupted inside * read(), or write(), but the signal is received before we actually hit the * read or write call. select() alleviates this problem by timing out * (configurable by pr_netio_set_poll_interval()), restarting the syscall if * PR_NETIO_SESS_INTR is not set, or returning if it is set and we were * interrupted by a signal. If after the timeout PR_NETIO_SESS_ABORT is set * (presumably by a signal handler) or PR_NETIO_SESS_INTR & errno == EINTR, * we return 1. Otherwise, return zero when data is available, or -1 on * other errors. */ int pr_netio_poll(pr_netio_stream_t *); /* Read, from the given stream, into the buffer the requested size_t number * of bytes. The int is the minimum number of bytes to read before * returning 1 (or greater). */ int pr_netio_read(pr_netio_stream_t *, char *, size_t, int); pr_netio_stream_t *pr_netio_reopen(pr_netio_stream_t *, int, int); int pr_netio_shutdown(pr_netio_stream_t *, int); /* pr_netio_telnet_gets() is exactly like pr_netio_gets(), except a few special * telnet characters are handled (which takes care of the [IAC]ABOR * command, and odd clients */ char *pr_netio_telnet_gets(char *, size_t, pr_netio_stream_t *, pr_netio_stream_t *); int pr_netio_write(pr_netio_stream_t *, char *, size_t); /* This is a bit odd, because io_ functions are opaque, we can't be sure * we are dealing with a conn_t or that it is in O_NONBLOCK mode. Trying * to do this without O_NONBLOCK would cause the kernel itself to block * here, and thus invalidate the whole principal. Instead we save * the flags and put the fd in O_NONBLOCK mode. */ int pr_netio_write_async(pr_netio_stream_t *, char *, size_t); void pr_netio_set_poll_interval(pr_netio_stream_t *, unsigned int); /* Allocate a NetIO object, and set all of its NetIO callbacks to their * default handlers. */ pr_netio_t *pr_alloc_netio(pool *); /* Register the given NetIO object and all its callbacks for the network * I/O layer's use. If given a NULL argument, it will automatically * instantiate and register the default NetIO object. */ int pr_register_netio(pr_netio_t *, int); /* Unregister the NetIO objects indicated by strm_types. */ int pr_unregister_netio(int); /* Initialize the network I/O layer. */ void init_netio(void); #endif /* PR_NETIO_H */