Network socket interface

Allocate and initialise a socket for use as a client or server. More...

Modules
	SSL socket support
	TLSv1 SSLv2 SSLv3 DTLSv1 support.
	Unix domain sockets
	Support for unixdomain sockets using sockets interface.
	Multicast sockets
	Support for multicast sockets either IPv4 or IPv6.

Files
file	socket.c
	Allocate and initialise a socket for use as a client or server.
file	sslutil.c
	TLSv1 SSLv2 SSLv3 DTLSv1 support.

Data Structures
union	sockstruct
	Socket union describing all address types. More...
struct	fwsocket
	Socket data structure. More...
struct	socket_handler
	Socket handling thread data. More...

Typedefs
typedef void(*	socketrecv )(struct fwsocket *, void *)
	Callback function to register with a socket that will be called when there is data available. More...

Enumerations
enum	sock_flags {   SOCK_FLAG_BIND = 1 << 0, SOCK_FLAG_CLOSE = 1 << 1, SOCK_FLAG_SSL = 1 << 2, SOCK_FLAG_UNIX = 1 << 3,   SOCK_FLAG_MCAST = 1 << 4 }
	Socket flags controling a socket. More...

Functions
void	close_socket (struct fwsocket *sock)
	Mark the socket for closure and release the reference. More...
struct fwsocket *	make_socket (int family, int type, int proto, void *ssl)
	Allocate a socket structure and return reference. More...
struct fwsocket *	accept_socket (struct fwsocket *sock)
	Create and return a socket structure from accept() More...
struct fwsocket *	sockconnect (int family, int stype, int proto, const char *ipaddr, const char *port, void *ssl)
	Generic client socket. More...
struct fwsocket *	udpconnect (const char *ipaddr, const char *port, void *ssl)
	UDP Socket client. More...
struct fwsocket *	tcpconnect (const char *ipaddr, const char *port, void *ssl)
	TCP Socket client. More...
struct fwsocket *	sockbind (int family, int stype, int proto, const char *ipaddr, const char *port, void *ssl, int backlog)
	Generic server socket. More...
struct fwsocket *	udpbind (const char *ipaddr, const char *port, void *ssl)
	UDP server socket. More...
struct fwsocket *	tcpbind (const char *ipaddr, const char *port, void *ssl, int backlog)
	Generic server socket. More...
void	socketserver (struct fwsocket *sock, socketrecv read, socketrecv acceptfunc, threadcleanup cleanup, void *data)
	Create a server thread with a socket that has been created with sockbind udpbind or tcpbind. More...
void	socketclient (struct fwsocket *sock, void *data, socketrecv read, threadcleanup cleanup)
	Create a server thread with a socket that has been created with sockbind udpbind or tcpbind. More...
const char *	sockaddr2ip (union sockstruct *addr, char *buff, int blen)
	Return the ip address of a sockstruct addr. More...
int	socketread_d (struct fwsocket *sock, void *buf, int num, union sockstruct *addr)
	Read from a socket into a buffer. More...
int	socketread (struct fwsocket *sock, void *buf, int num)
	Read from a socket into a buffer. More...
int	socketwrite_d (struct fwsocket *sock, const void *buf, int num, union sockstruct *addr)
	Write a buffer to a socket. More...
int	socketwrite (struct fwsocket *sock, const void *buf, int num)
	Write a buffer to a socket. More...

Detailed Description

Allocate and initialise a socket for use as a client or server.

See Also

Socket Interface

Socket Example (Echo Server/Client)

Typedef Documentation

typedef void(* socketrecv)(struct fwsocket *, void *)

Callback function to register with a socket that will be called when there is data available.

Parameters

sock	Socket structure data arrived on.
data	Reference to data held by client/server thread.

Definition at line 259 of file dtsapp.h.

Enumeration Type Documentation

enum sock_flags

Socket flags controling a socket.

Enumerator
SOCK_FLAG_BIND	The socket has been bound and awaiting connections.
SOCK_FLAG_CLOSE	The socket is going away stop processing in its thread.
SOCK_FLAG_SSL	SSL has been requested on this socket dont allow clear read/send.
SOCK_FLAG_UNIX	UNIX Domain Socket.
SOCK_FLAG_MCAST	Multicast Socket.

Definition at line 102 of file dtsapp.h.

                {
    SOCK_FLAG_BIND      = 1 << 0,
    SOCK_FLAG_CLOSE     = 1 << 1,
    SOCK_FLAG_SSL       = 1 << 2,
    SOCK_FLAG_UNIX      = 1 << 3,
    SOCK_FLAG_MCAST     = 1 << 4
};

Function Documentation

struct fwsocket* accept_socket

(

struct fwsocket *

sock

)

Create and return a socket structure from accept()

Parameters

sock	Reference to the socket its accepted on.

Returns

Reference to new socket.

Definition at line 144 of file socket.c.

References fwsocket::addr, objalloc(), objlock(), objunlock(), objunref(), fwsocket::proto, sockstruct::sa, fwsocket::sock, fwsocket::ssl, tlsaccept(), and fwsocket::type.

                                                             {
    struct fwsocket *si;
    socklen_t salen = sizeof(si->addr);

    if (!(si = objalloc(sizeof(*si),clean_fwsocket))) {
        return NULL;
    }

    objlock(sock);
    if ((si->sock = accept(sock->sock, &si->addr.sa, &salen)) < 0) {
        objunlock(sock);
        objunref(si);
        return NULL;
    }

    si->type = sock->type;
    si->proto = sock->proto;

    if (sock->ssl) {
        tlsaccept(si, sock->ssl);
    }
    objunlock(sock);

    return (si);
}

void close_socket

(

struct fwsocket *

sock

)

Mark the socket for closure and release the reference.

Parameters

sock	Socket to close.

Definition at line 79 of file socket.c.

References objunref(), setflag, and SOCK_FLAG_CLOSE.

Referenced by socktest(), and unixsocktest().

                                                {
    if (sock) {
        setflag(sock, SOCK_FLAG_CLOSE);
        objunref(sock);
    }
}

struct fwsocket* make_socket	(	int	family,
		int	type,
		int	proto,
		void *	ssl
	)

Allocate a socket structure and return reference.

The socket FD is assined by a call to socket.

Warning

This function should not be called directly.

Parameters

family	Protocol family.
type	Socket type.
proto	Protocol to be used.
ssl	SSL structure to associate with the socket.

Returns

Reference to socket structure holding a FD.

Definition at line 120 of file socket.c.

References objalloc(), objunref(), fwsocket::proto, fwsocket::sock, fwsocket::ssl, and fwsocket::type.

Referenced by dtls_listenssl(), mcast_socket(), unixsocket_client(), and unixsocket_server().

                                                                                {
    struct fwsocket *si;

    if (!(si = objalloc(sizeof(*si),clean_fwsocket))) {
        return NULL;
    }

    if ((si->sock = socket(family, type, proto)) < 0) {
        objunref(si);
        return NULL;
    };

    if (ssl) {
        si->ssl = ssl;
    }
    si->type = type;
    si->proto = proto;

    return (si);
}

const char* sockaddr2ip	(	union sockstruct *	addr,
		char *	buff,
		int	blen
	)

Return the ip address of a sockstruct addr.

Parameters

addr	Socketstruct to return the address for.
buff	Buffer the IP will be copied too.
blen	Buffer length.

Returns

a pointer to buff.

Definition at line 504 of file socket.c.

References inet_ntop(), sockstruct::sa4, sockstruct::sa6, and sockstruct::ss.

                                                                      {
    if (!buff) {
        return NULL;
    }

    switch (addr->ss.ss_family) {
        case PF_INET:
            inet_ntop(PF_INET, &addr->sa4.sin_addr, buff, blen);
            break;
        case PF_INET6:
            inet_ntop(PF_INET6, &addr->sa6.sin6_addr, buff, blen);
            break;
    }
    return buff;
}

struct fwsocket* sockbind	(	int	family,
		int	stype,
		int	proto,
		const char *	ipaddr,
		const char *	port,
		void *	ssl,
		int	backlog
	)

Generic server socket.

See Also

udpbind

tcpbind

Parameters

family	Protocol family.
stype	Socket type.
proto	Socket protocol.
ipaddr	Ipaddr to connect too.
port	Port to connect too.
ssl	SSL structure to associate with socket.
backlog	Connection backlog passed to listen.

Returns

Reference to socket structure.

Definition at line 290 of file socket.c.

                                                                                                                                 {
    return(_opensocket(family, stype, proto, ipaddr, port, ssl, 1, backlog));
}

struct fwsocket* sockconnect	(	int	family,
		int	stype,
		int	proto,
		const char *	ipaddr,
		const char *	port,
		void *	ssl
	)

Generic client socket.

See Also

udpconnect

tcpconnect

Parameters

family	Protocol family.
stype	Socket type.
proto	Socket protocol.
ipaddr	Ipaddr to connect too.
port	Port to connect too.
ssl	SSL structure to associate with socket.

Returns

Reference to socket structure.

Definition at line 250 of file socket.c.

                                                                                                                       {
    return(_opensocket(family, stype, proto, ipaddr, port, ssl, 0, 0));
}

void socketclient	(	struct fwsocket *	sock,
		void *	data,
		socketrecv	read,
		threadcleanup	cleanup
	)

Create a server thread with a socket that has been created with sockbind udpbind or tcpbind.

See Also

sockclient

threadcleanup

socketrecv

Parameters

sock	Reference to a bound socket.
data	to send to the callbacks in paramaters.
read	Callback to handle data when ready to read.
cleanup	Thread cleanup function for when the socket closes.

Definition at line 493 of file socket.c.

References startsslclient().

Referenced by socktest().

                                                                                                    {
    startsslclient(sock);

    _start_socket_handler(sock, read, NULL, cleanup, data);
}

int socketread	(	struct fwsocket *	sock,
		void *	buf,
		int	num
	)

Read from a socket into a buffer.

There are 2 functions each for reading and writing data to a socket.

Connected (client) sockets (Including UDP [SOCK_DGRAM])

Use of socketwrite and socketread is acceptable.

UDP (SOCK_DGRAM) servers.

These require use of socketread_d and socketwrite_d the exception is DTLS connections that use there own routines and either works.

Parameters

sock	Socket structure to read from.
buf	Buffer to fill.
num	Size of the buffer.

Returns

Number of bytes read or -1 on error 0 will indicate connection closed.

Definition at line 489 of file sslutil.c.

References socketread_d().

Referenced by client_func().

                                                                 {
    return (socketread_d(sock, buf, num, NULL));
}

int socketread_d	(	struct fwsocket *	sock,
		void *	buf,
		int	num,
		union sockstruct *	addr
	)

Read from a socket into a buffer.

There are 2 functions each for reading and writing data to a socket.

Connected (client) sockets (Including UDP [SOCK_DGRAM])

Use of socketwrite and socketread is acceptable.

UDP (SOCK_DGRAM) servers.

These require use of socketread_d and socketwrite_d the exception is DTLS connections that use there own routines and either works.

Parameters

sock	Socket structure to read from.
buf	Buffer to fill.
num	Size of the buffer.
addr	Addr structure to fill remote address in.

Returns

Number of bytes read or -1 on error 0 will indicate connection closed.

Definition at line 406 of file sslutil.c.

References fwsocket::flags, objlock(), objunlock(), objunref(), sockstruct::sa, fwsocket::sock, SOCK_FLAG_CLOSE, SOCK_FLAG_SSL, ssldata::ssl, fwsocket::ssl, testflag, and fwsocket::type.

Referenced by server_func(), and socketread().

                                                                                           {
    struct ssldata *ssl = sock->ssl;
    socklen_t salen = sizeof(*addr);
    int ret, err, syserr;

    if (!ssl && !testflag(sock, SOCK_FLAG_SSL)) {
        objlock(sock);
        if (addr && (sock->type == SOCK_DGRAM)) {
            ret = recvfrom(sock->sock, buf, num, 0, &addr->sa, &salen);
        } else {
#ifndef __WIN32
            ret = read(sock->sock, buf, num);
#else
            ret = recv(sock->sock, buf, num, 0);
#endif
        }
        if (ret == 0) {
            sock->flags |= SOCK_FLAG_CLOSE;
        }
        objunlock(sock);
        return (ret);
    } else if (!ssl) {
        return -1;
    }

    objlock(ssl);
    /* ive been shutdown*/
    if (!ssl->ssl) {
        objunlock(ssl);
        return (-1);
    }
    ret = SSL_read(ssl->ssl, buf, num);
    err = SSL_get_error(ssl->ssl, ret);
    if (ret == 0) {
        sock->flags |= SOCK_FLAG_CLOSE;
    }
    objunlock(ssl);
    switch (err) {
        case SSL_ERROR_NONE:
            break;
        case SSL_ERROR_WANT_X509_LOOKUP:
            printf("Want X509\n");
            break;
        case SSL_ERROR_WANT_READ:
            printf("Read Want Read\n");
            break;
        case SSL_ERROR_WANT_WRITE:
            printf("Read Want write\n");
            break;
        case SSL_ERROR_ZERO_RETURN:
        case SSL_ERROR_SSL:
            objlock(sock);
            objunref(sock->ssl);
            sock->ssl = NULL;
            objunlock(sock);
            break;
        case SSL_ERROR_SYSCALL:
            syserr = ERR_get_error();
            if (syserr || (!syserr && (ret == -1))) {
                printf("R syscall %i %i\n", syserr, ret);
            }
            break;
        default
                :
            printf("other\n");
            break;
    }

    return (ret);
}

void socketserver	(	struct fwsocket *	sock,
		socketrecv	read,
		socketrecv	acceptfunc,
		threadcleanup	cleanup,
		void *	data
	)

Create a server thread with a socket that has been created with sockbind udpbind or tcpbind.

See Also

sockclient

threadcleanup

socketrecv

Parameters

sock	Reference to a bound socket.
read	Callback to handle data when ready to read.
acceptfunc	Function to call on connection accept.
cleanup	Thread cleanup function for when the socket closes.
data	to send to the callbacks in paramaters.

Definition at line 463 of file socket.c.

References fwsocket::children, create_bucketlist(), dtsl_serveropts(), fwsocket::flags, objlock(), objunlock(), fwsocket::ssl, and fwsocket::type.

Referenced by socktest().

                                                                                   {

    objlock(sock);
    if (sock->flags & SOCK_FLAG_BIND) {
        if (sock->ssl || !(sock->type == SOCK_DGRAM)) {
            sock->children = create_bucketlist(6, hash_socket);
        }
        if (sock->ssl && (sock->type == SOCK_DGRAM)) {
            objunlock(sock);
            dtsl_serveropts(sock);
        } else {
            objunlock(sock);
        }
    } else {
        objunlock(sock);
    }
    _start_socket_handler(sock, read, acceptfunc, cleanup, data);
}

int socketwrite	(	struct fwsocket *	sock,
		const void *	buf,
		int	num
	)

Write a buffer to a socket.

There are 2 functions each for reading and writing data to a socket.

Connected (client) sockets (Including UDP [SOCK_DGRAM])

Use of socketwrite and socketread is acceptable.

UDP (SOCK_DGRAM) servers.

These require use of socketread_d and socketwrite_d the exception is DTLS connections that use there own routines and either works.

Parameters

sock	Socket structure to send data too.
buf	Buffer to send.
num	Lengthe of the buffer.

Returns

Number of bytes written or -1 on error 0 will indicate some error in SSL.

Definition at line 629 of file sslutil.c.

References socketwrite_d().

Referenced by client_func(), and socktest().

                                                                        {
    return (socketwrite_d(sock, buf, num, NULL));
}

int socketwrite_d	(	struct fwsocket *	sock,
		const void *	buf,
		int	num,
		union sockstruct *	addr
	)

Write a buffer to a socket.

There are 2 functions each for reading and writing data to a socket.

Connected (client) sockets (Including UDP [SOCK_DGRAM])

Use of socketwrite and socketread is acceptable.

UDP (SOCK_DGRAM) servers.

These require use of socketread_d and socketwrite_d the exception is DTLS connections that use there own routines and either works.

Todo:

implement send/sendto in WIN32

Parameters

sock	Socket structure to send data too.
buf	Buffer to send.
num	Lengthe of the buffer.
addr	Addr structure to send the buffer too (SOCK_DGRAM) see notes.

Returns

Number of bytes written or -1 on error 0 will indicate some error in SSL.

Definition at line 508 of file sslutil.c.

References fwsocket::addr, fwsocket::flags, objlock(), objunlock(), objunref(), sockstruct::sa, setflag, fwsocket::sock, SOCK_FLAG_CLOSE, SOCK_FLAG_MCAST, SOCK_FLAG_SSL, SOCK_FLAG_UNIX, sockstruct::ss, ssldata::ssl, fwsocket::ssl, testflag, fwsocket::type, and sockstruct::un.

Referenced by server_func(), socketwrite(), and unixsocktest().

                                                                                                  {
    struct ssldata *ssl = (sock) ? sock->ssl : NULL;
    int ret, err, syserr;

    if (!sock) {
        return (-1);
    }

    if (!ssl && !testflag(sock, SOCK_FLAG_SSL)) {
        objlock(sock);
        if (addr && (sock->type == SOCK_DGRAM)) {
#ifndef __WIN32
            if (sock->flags & SOCK_FLAG_UNIX) {
                ret = sendto(sock->sock, buf, num, MSG_NOSIGNAL, (const struct sockaddr *)&addr->un, sizeof(addr->un));
            } else if (sock->flags & SOCK_FLAG_MCAST) {
                ret = sendto(sock->sock, buf, num, MSG_NOSIGNAL, &sock->addr.sa, sizeof(sock->addr.ss));
            } else {
                ret = sendto(sock->sock, buf, num, MSG_NOSIGNAL, &addr->sa, sizeof(*addr));
            }
#else
            if (sock->flags & SOCK_FLAG_MCAST) {
                ret = sendto(sock->sock, buf, num, 0, &sock->addr.sa, sizeof(sock->addr.ss));
            } else {
                ret = sendto(sock->sock, buf, num, 0, &addr->sa, sizeof(*addr));
            }
#endif
        } else {
#ifndef __WIN32
            if (sock->flags & SOCK_FLAG_MCAST) {
                ret = sendto(sock->sock, buf, num, MSG_NOSIGNAL, &sock->addr.sa, sizeof(sock->addr.ss));
            } else {
                ret = send(sock->sock, buf, num, MSG_NOSIGNAL);
            }
#else
            if (sock->flags & SOCK_FLAG_MCAST) {
                ret = sendto(sock->sock, buf, num, 0, &sock->addr.sa, sizeof(sock->addr.ss));
            } else {
                ret = send(sock->sock, buf, num, 0);
            }
#endif
        }
        if (ret == -1) {
            switch(errno) {
                case EBADF:
                case EPIPE:
#ifndef __WIN32
                case ENOTCONN:
                case ENOTSOCK:
#endif
                    sock->flags |= SOCK_FLAG_CLOSE;
                    break;
            }
        }
        objunlock(sock);
        return (ret);
    } else if (!ssl) {
        return -1;
    }

    if (ssl && ssl->ssl) {
        objlock(ssl);
        if (SSL_state(ssl->ssl) != SSL_ST_OK) {
            objunlock(ssl);
            return (SSL_ERROR_SSL);
        }
        ret = SSL_write(ssl->ssl, buf, num);
        err = SSL_get_error(ssl->ssl, ret);
        objunlock(ssl);
    } else {
        return -1;
    }

    if (ret == -1) {
        setflag(sock, SOCK_FLAG_CLOSE);
    }

    switch(err) {
        case SSL_ERROR_NONE:
            break;
        case SSL_ERROR_WANT_READ:
            printf("Send Want Read\n");
            break;
        case SSL_ERROR_WANT_WRITE:
            printf("Send Want write\n");
            break;
        case SSL_ERROR_WANT_X509_LOOKUP:
            printf("Want X509\n");
            break;
        case SSL_ERROR_ZERO_RETURN:
        case SSL_ERROR_SSL:
            objlock(sock);
            objunref(sock->ssl);
            sock->ssl = NULL;
            objunlock(sock);
            break;
        case SSL_ERROR_SYSCALL:
            syserr = ERR_get_error();
            if (syserr || (!syserr && (ret == -1))) {
                printf("W syscall %i %i\n", syserr, ret);
            }
            break;
        default:
            printf("other\n");
            break;
    }

    return (ret);
}

struct fwsocket* tcpbind	(	const char *	ipaddr,
		const char *	port,
		void *	ssl,
		int	backlog
	)

Generic server socket.

See Also

udpbind

sockbind

Parameters

ipaddr	Ipaddr to connect too.
port	Port to connect too.
ssl	SSL structure to associate with socket.
backlog	Connection backlog passed to listen.

Returns

Reference to socket structure.

Definition at line 315 of file socket.c.

Referenced by socktest().

                                                                                              {
    return (_opensocket(PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, ipaddr, port, ssl, 1, backlog));
}

struct fwsocket* tcpconnect	(	const char *	ipaddr,
		const char *	port,
		void *	ssl
	)

TCP Socket client.

See Also

sockconnect

udpconnect

Parameters

ipaddr	Ipaddr to connect too.
port	Port to connect too.
ssl	SSL structure to associate with socket.

Returns

Reference to socket structure.

Definition at line 274 of file socket.c.

Referenced by socktest().

                                                                                    {
    return (_opensocket(PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, ipaddr, port, ssl, 0, 0));
}

struct fwsocket* udpbind	(	const char *	ipaddr,
		const char *	port,
		void *	ssl
	)

UDP server socket.

See Also

sockbind

tcpbind

Parameters

ipaddr	Ipaddr to connect too.
port	Port to connect too.
ssl	SSL structure to associate with socket.

Returns

Reference to socket structure.

Definition at line 302 of file socket.c.

Referenced by socktest().

                                                                                 {
    return (_opensocket(PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, ipaddr, port, ssl, 1, 0));
}

struct fwsocket* udpconnect	(	const char *	ipaddr,
		const char *	port,
		void *	ssl
	)

UDP Socket client.

See Also

sockconnect

tcpconnect

Parameters

ipaddr	Ipaddr to connect too.
port	Port to connect too.
ssl	SSL structure to associate with socket.

Returns

Reference to socket structure.

Definition at line 262 of file socket.c.

Referenced by socktest().

                                                                                    {
    return (_opensocket(PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, ipaddr, port, ssl, 0, 0));
}