glibc/bits/socket.h
Florian Weimer 26e7005728 socket: Use may_alias on sockaddr structs (bug 19622)
This supports common coding patterns.  The GCC C front end before
version 7 rejects the may_alias attribute on a struct definition
if it was not present in a previous forward declaration, so this
attribute can only be conditionally applied.

This implements the spirit of the change in Austin Group issue 1641.

Suggested-by: Marek Polacek <polacek@redhat.com>
Suggested-by: Jakub Jelinek <jakub@redhat.com>
Reviewed-by: Sam James <sam@gentoo.org>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
(cherry picked from commit 8d7b6b4cb2)
2024-05-27 17:25:13 +02:00

392 lines
14 KiB
C

/* System-specific socket constants and types. 4.4 BSD version.
Copyright (C) 1991-2024 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, see <https://www.gnu.org/licenses/>. */
#ifndef __BITS_SOCKET_H
#define __BITS_SOCKET_H 1
#ifndef _SYS_SOCKET_H
# error "Never include <bits/socket.h> directly; use <sys/socket.h> instead."
#endif
#define __need_size_t
#include <stddef.h>
#include <bits/wordsize.h>
#include <bits/types.h>
/* Type for length arguments in socket calls. */
#ifndef __socklen_t_defined
typedef __socklen_t socklen_t;
# define __socklen_t_defined
#endif
/* Types of sockets. */
enum __socket_type
{
SOCK_STREAM = 1, /* Sequenced, reliable, connection-based
byte streams. */
#define SOCK_STREAM SOCK_STREAM
SOCK_DGRAM = 2, /* Connectionless, unreliable datagrams
of fixed maximum length. */
#define SOCK_DGRAM SOCK_DGRAM
SOCK_RAW = 3, /* Raw protocol interface. */
#define SOCK_RAW SOCK_RAW
SOCK_RDM = 4, /* Reliably-delivered messages. */
#define SOCK_RDM SOCK_RDM
SOCK_SEQPACKET = 5, /* Sequenced, reliable, connection-based,
datagrams of fixed maximum length. */
#define SOCK_SEQPACKET SOCK_SEQPACKET
#define SOCK_MAX (SOCK_SEQPACKET + 1)
/* Mask which covers at least up to SOCK_MASK-1.
The remaining bits are used as flags. */
#define SOCK_TYPE_MASK 0xf
/* Flags to be ORed into the type parameter of socket and socketpair and
used for the flags parameter of accept4. */
SOCK_CLOEXEC = 0x10000000, /* Atomically set close-on-exec flag for the
new descriptor(s). */
#define SOCK_CLOEXEC SOCK_CLOEXEC
SOCK_NONBLOCK = 0x20000000 /* Atomically mark descriptor(s) as
non-blocking. */
#define SOCK_NONBLOCK SOCK_NONBLOCK
};
/* Protocol families. */
#define PF_UNSPEC 0 /* Unspecified. */
#define PF_LOCAL 1 /* Local to host (pipes and file-domain). */
#define PF_UNIX PF_LOCAL /* Old BSD name for PF_LOCAL. */
#define PF_FILE PF_LOCAL /* POSIX name for PF_LOCAL. */
#define PF_INET 2 /* IP protocol family. */
#define PF_IMPLINK 3 /* ARPAnet IMP protocol. */
#define PF_PUP 4 /* PUP protocols. */
#define PF_CHAOS 5 /* MIT Chaos protocols. */
#define PF_NS 6 /* Xerox NS protocols. */
#define PF_ISO 7 /* ISO protocols. */
#define PF_OSI PF_ISO
#define PF_ECMA 8 /* ECMA protocols. */
#define PF_DATAKIT 9 /* AT&T Datakit protocols. */
#define PF_CCITT 10 /* CCITT protocols (X.25 et al). */
#define PF_SNA 11 /* IBM SNA protocol. */
#define PF_DECnet 12 /* DECnet protocols. */
#define PF_DLI 13 /* Direct data link interface. */
#define PF_LAT 14 /* DEC Local Area Transport protocol. */
#define PF_HYLINK 15 /* NSC Hyperchannel protocol. */
#define PF_APPLETALK 16 /* Don't use this. */
#define PF_ROUTE 17 /* Internal Routing Protocol. */
#define PF_LINK 18 /* Link layer interface. */
#define PF_XTP 19 /* eXpress Transfer Protocol (no AF). */
#define PF_COIP 20 /* Connection-oriented IP, aka ST II. */
#define PF_CNT 21 /* Computer Network Technology. */
#define PF_RTIP 22 /* Help Identify RTIP packets. **/
#define PF_IPX 23 /* Novell Internet Protocol. */
#define PF_SIP 24 /* Simple Internet Protocol. */
#define PF_PIP 25 /* Help Identify PIP packets. */
#define PF_INET6 26 /* IP version 6. */
#define PF_MAX 27
/* Address families. */
#define AF_UNSPEC PF_UNSPEC
#define AF_LOCAL PF_LOCAL
#define AF_UNIX PF_UNIX
#define AF_FILE PF_FILE
#define AF_INET PF_INET
#define AF_IMPLINK PF_IMPLINK
#define AF_PUP PF_PUP
#define AF_CHAOS PF_CHAOS
#define AF_NS PF_NS
#define AF_ISO PF_ISO
#define AF_OSI PF_OSI
#define AF_ECMA PF_ECMA
#define AF_DATAKIT PF_DATAKIT
#define AF_CCITT PF_CCITT
#define AF_SNA PF_SNA
#define AF_DECnet PF_DECnet
#define AF_DLI PF_DLI
#define AF_LAT PF_LAT
#define AF_HYLINK PF_HYLINK
#define AF_APPLETALK PF_APPLETALK
#define AF_ROUTE PF_ROUTE
#define AF_LINK PF_LINK
#ifdef __USE_MISC
# define pseudo_AF_XTP PF_XTP
#endif
#define AF_COIP PF_COIP
#define AF_CNT PF_CNT
#ifdef __USE_MISC
# define pseudo_AF_RTIP PF_RTIP
#endif
#define AF_IPX PF_IPX
#define AF_SIP PF_SIP
#ifdef __USE_MISC
# define pseudo_AF_PIP PF_PIP
#endif
#define AF_INET6 PF_INET6
#define AF_MAX PF_MAX
/* Maximum queue length specifiable by listen. */
#define SOMAXCONN 128 /* 5 on the original 4.4 BSD. */
/* Get the definition of the macro to define the common sockaddr members. */
#include <bits/sockaddr.h>
/* Structure describing a generic socket address. */
struct __attribute_struct_may_alias__ sockaddr
{
__SOCKADDR_COMMON (sa_); /* Common data: address family and length. */
char sa_data[14]; /* Address data. */
};
/* Structure large enough to hold any socket address (with the historical
exception of AF_UNIX). */
#if __WORDSIZE == 64
# define __ss_aligntype __uint64_t
#else
# define __ss_aligntype __uint32_t
#endif
#define _SS_PADSIZE \
(_SS_SIZE - __SOCKADDR_COMMON_SIZE - sizeof (__ss_aligntype))
struct __attribute_struct_may_alias__ sockaddr_storage
{
__SOCKADDR_COMMON (ss_); /* Address family, etc. */
char __ss_padding[_SS_PADSIZE];
__ss_aligntype __ss_align; /* Force desired alignment. */
};
/* Bits in the FLAGS argument to `send', `recv', et al. */
enum
{
MSG_OOB = 0x01, /* Process out-of-band data. */
#define MSG_OOB MSG_OOB
MSG_PEEK = 0x02, /* Peek at incoming messages. */
#define MSG_PEEK MSG_PEEK
MSG_DONTROUTE = 0x04, /* Don't use local routing. */
#define MSG_DONTROUTE MSG_DONTROUTE
MSG_EOR = 0x08, /* Data completes record. */
#define MSG_EOR MSG_EOR
MSG_TRUNC = 0x10, /* Data discarded before delivery. */
#define MSG_TRUNC MSG_TRUNC
MSG_CTRUNC = 0x20, /* Control data lost before delivery. */
#define MSG_CTRUNC MSG_CTRUNC
MSG_WAITALL = 0x40, /* Wait for full request or error. */
#define MSG_WAITALL MSG_WAITALL
MSG_DONTWAIT = 0x80, /* This message should be nonblocking. */
#define MSG_DONTWAIT MSG_DONTWAIT
MSG_NOSIGNAL = 0x0400 /* Do not generate SIGPIPE on EPIPE. */
#define MSG_NOSIGNAL MSG_NOSIGNAL
};
/* Structure describing messages sent by
`sendmsg' and received by `recvmsg'. */
struct msghdr
{
void *msg_name; /* Address to send to/receive from. */
socklen_t msg_namelen; /* Length of address data. */
struct iovec *msg_iov; /* Vector of data to send/receive into. */
int msg_iovlen; /* Number of elements in the vector. */
void *msg_control; /* Ancillary data (eg BSD filedesc passing). */
socklen_t msg_controllen; /* Ancillary data buffer length. */
int msg_flags; /* Flags in received message. */
};
/* Structure used for storage of ancillary data object information. */
struct cmsghdr
{
socklen_t cmsg_len; /* Length of data in cmsg_data plus length
of cmsghdr structure. */
int cmsg_level; /* Originating protocol. */
int cmsg_type; /* Protocol specific type. */
#if __glibc_c99_flexarr_available
__extension__ unsigned char __cmsg_data __flexarr; /* Ancillary data. */
#endif
};
/* Ancillary data object manipulation macros. */
#if __glibc_c99_flexarr_available
# define CMSG_DATA(cmsg) ((cmsg)->__cmsg_data)
#else
# define CMSG_DATA(cmsg) ((unsigned char *) ((struct cmsghdr *) (cmsg) + 1))
#endif
#define CMSG_NXTHDR(mhdr, cmsg) __cmsg_nxthdr (mhdr, cmsg)
#define CMSG_FIRSTHDR(mhdr) \
((size_t) (mhdr)->msg_controllen >= sizeof (struct cmsghdr) \
? (struct cmsghdr *) (mhdr)->msg_control : (struct cmsghdr *) 0)
#define CMSG_ALIGN(len) (((len) + sizeof (size_t) - 1) \
& (size_t) ~(sizeof (size_t) - 1))
#define CMSG_SPACE(len) (CMSG_ALIGN (len) \
+ CMSG_ALIGN (sizeof (struct cmsghdr)))
#define CMSG_LEN(len) (CMSG_ALIGN (sizeof (struct cmsghdr)) + (len))
/* Given a length, return the additional padding necessary such that
len + __CMSG_PADDING(len) == CMSG_ALIGN (len). */
#define __CMSG_PADDING(len) ((sizeof (size_t) \
- ((len) & (sizeof (size_t) - 1))) \
& (sizeof (size_t) - 1))
extern struct cmsghdr *__cmsg_nxthdr (struct msghdr *__mhdr,
struct cmsghdr *__cmsg) __THROW;
#ifdef __USE_EXTERN_INLINES
# ifndef _EXTERN_INLINE
# define _EXTERN_INLINE __extern_inline
# endif
_EXTERN_INLINE struct cmsghdr *
__NTH (__cmsg_nxthdr (struct msghdr *__mhdr, struct cmsghdr *__cmsg))
{
/* We may safely assume that __cmsg lies between __mhdr->msg_control and
__mhdr->msg_controllen because the user is required to obtain the first
cmsg via CMSG_FIRSTHDR, set its length, then obtain subsequent cmsgs
via CMSG_NXTHDR, setting lengths along the way. However, we don't yet
trust the value of __cmsg->cmsg_len and therefore do not use it in any
pointer arithmetic until we check its value. */
unsigned char * __msg_control_ptr = (unsigned char *) __mhdr->msg_control;
unsigned char * __cmsg_ptr = (unsigned char *) __cmsg;
size_t __size_needed = sizeof (struct cmsghdr)
+ __CMSG_PADDING (__cmsg->cmsg_len);
/* The current header is malformed, too small to be a full header. */
if ((size_t) __cmsg->cmsg_len < sizeof (struct cmsghdr))
return (struct cmsghdr *) 0;
/* There isn't enough space between __cmsg and the end of the buffer to
hold the current cmsg *and* the next one. */
if (((size_t)
(__msg_control_ptr + __mhdr->msg_controllen - __cmsg_ptr)
< __size_needed)
|| ((size_t)
(__msg_control_ptr + __mhdr->msg_controllen - __cmsg_ptr
- __size_needed)
< __cmsg->cmsg_len))
return (struct cmsghdr *) 0;
/* Now, we trust cmsg_len and can use it to find the next header. */
__cmsg = (struct cmsghdr *) ((unsigned char *) __cmsg
+ CMSG_ALIGN (__cmsg->cmsg_len));
return __cmsg;
}
#endif /* Use `extern inline'. */
/* Socket level message types. */
enum
{
SCM_RIGHTS = 0x01, /* Access rights (array of int). */
#define SCM_RIGHTS SCM_RIGHTS
SCM_TIMESTAMP = 0x02, /* Timestamp (struct timeval). */
#define SCM_TIMESTAMP SCM_TIMESTAMP
SCM_CREDS = 0x03 /* Process creds (struct cmsgcred). */
#define SCM_CREDS SCM_CREDS
};
#ifdef __USE_MISC
/* Unfortunately, BSD practice dictates this structure be of fixed size.
If there are more than CMGROUP_MAX groups, the list is truncated.
(On GNU systems, the `cmcred_euid' field is just the first in the
list of effective UIDs.) */
#define CMGROUP_MAX 16
/* Structure delivered by SCM_CREDS. This describes the identity of the
sender of the data simultaneously received on the socket. By BSD
convention, this is included only when a sender on a AF_LOCAL socket
sends cmsg data of this type and size; the sender's structure is
ignored, and the system fills in the various IDs of the sender process. */
struct cmsgcred
{
__pid_t cmcred_pid;
__uid_t cmcred_uid;
__uid_t cmcred_euid;
__gid_t cmcred_gid;
int cmcred_ngroups;
__gid_t cmcred_groups[CMGROUP_MAX];
};
#endif
/* Protocol number used to manipulate socket-level options
with `getsockopt' and `setsockopt'. */
#define SOL_SOCKET 0xffff
/* Socket-level options for `getsockopt' and `setsockopt'. */
enum
{
SO_DEBUG = 0x0001, /* Record debugging information. */
#define SO_DEBUG SO_DEBUG
SO_ACCEPTCONN = 0x0002, /* Accept connections on socket. */
#define SO_ACCEPTCONN SO_ACCEPTCONN
SO_REUSEADDR = 0x0004, /* Allow reuse of local addresses. */
#define SO_REUSEADDR SO_REUSEADDR
SO_KEEPALIVE = 0x0008, /* Keep connections alive and send
SIGPIPE when they die. */
#define SO_KEEPALIVE SO_KEEPALIVE
SO_DONTROUTE = 0x0010, /* Don't do local routing. */
#define SO_DONTROUTE SO_DONTROUTE
SO_BROADCAST = 0x0020, /* Allow transmission of
broadcast messages. */
#define SO_BROADCAST SO_BROADCAST
SO_USELOOPBACK = 0x0040, /* Use the software loopback to avoid
hardware use when possible. */
#define SO_USELOOPBACK SO_USELOOPBACK
SO_LINGER = 0x0080, /* Block on close of a reliable
socket to transmit pending data. */
#define SO_LINGER SO_LINGER
SO_OOBINLINE = 0x0100, /* Receive out-of-band data in-band. */
#define SO_OOBINLINE SO_OOBINLINE
SO_REUSEPORT = 0x0200, /* Allow local address and port reuse. */
#define SO_REUSEPORT SO_REUSEPORT
SO_SNDBUF = 0x1001, /* Send buffer size. */
#define SO_SNDBUF SO_SNDBUF
SO_RCVBUF = 0x1002, /* Receive buffer. */
#define SO_RCVBUF SO_RCVBUF
SO_SNDLOWAT = 0x1003, /* Send low-water mark. */
#define SO_SNDLOWAT SO_SNDLOWAT
SO_RCVLOWAT = 0x1004, /* Receive low-water mark. */
#define SO_RCVLOWAT SO_RCVLOWAT
SO_SNDTIMEO = 0x1005, /* Send timeout. */
#define SO_SNDTIMEO SO_SNDTIMEO
SO_RCVTIMEO = 0x1006, /* Receive timeout. */
#define SO_RCVTIMEO SO_RCVTIMEO
SO_ERROR = 0x1007, /* Get and clear error status. */
#define SO_ERROR SO_ERROR
SO_STYLE = 0x1008, /* Get socket connection style. */
#define SO_STYLE SO_STYLE
SO_TYPE = SO_STYLE /* Compatible name for SO_STYLE. */
#define SO_TYPE SO_TYPE
};
/* Structure used to manipulate the SO_LINGER option. */
struct linger
{
int l_onoff; /* Nonzero to linger on close. */
int l_linger; /* Time to linger. */
};
#endif /* bits/socket.h */