RPC(3) | Library Functions Manual | RPC(3) |
NAME¶
rpc
— library
routines for remote procedure calls
SYNOPSIS¶
#include
<rpc/rpc.h>
#include <netconfig.h>
DESCRIPTION¶
These routines allow C language programs to make procedure calls on other machines across a network. First, the client sends a request to the server. On receipt of the request, the server calls a dispatch routine to perform the requested service, and then sends back a reply.
All RPC routines require the header
<rpc/rpc.h>
. Routines that
take a struct netconfig also require that
<netconfig.h>
be
included.
Nettype¶
Some of the high-level RPC interface routines take a
nettype string as one of the arguments (for example,
clnt_create
(),
svc_create
(),
rpc_reg
(),
rpc_call
()).
This string defines a class of transports which can be used for a particular
application.
The nettype argument can be one of the following:
- netpath
- Choose from the transports which have been indicated by their token names
in the
NETPATH
environment variable.NETPATH
is unset orNULL
, it defaults to "visible". "netpath" is the default nettype. - visible
- Choose the transports which have the visible flag (v) set in the /etc/netconfig file.
- circuit_v
- This is same as "visible" except that it chooses only the connection oriented transports (semantics "tpi_cots" or "tpi_cots_ord") from the entries in the /etc/netconfig file.
- datagram_v
- This is same as "visible" except that it chooses only the connectionless datagram transports (semantics "tpi_clts") from the entries in the /etc/netconfig file.
- circuit_n
- This is same as "netpath" except that it chooses only the connection oriented datagram transports (semantics "tpi_cots" or "tpi_cots_ord").
- datagram_n
- This is same as "netpath" except that it chooses only the connectionless datagram transports (semantics "tpi_clts").
- udp
- This refers to Internet UDP, both version 4 and 6.
- tcp
- This refers to Internet TCP, both version 4 and 6.
If nettype is NULL
,
it defaults to "netpath". The transports are tried in left to
right order in the NETPATH
variable or in top to
down order in the /etc/netconfig file.
Derived Types¶
The derived types used in the RPC interfaces are defined as follows:
typedef u_int32_t rpcprog_t; typedef u_int32_t rpcvers_t; typedef u_int32_t rpcproc_t; typedef u_int32_t rpcprot_t; typedef u_int32_t rpcport_t; typedef int32_t rpc_inline_t;
Data Structures¶
Some of the data structures used by the RPC package are shown below.
The AUTH Structure¶
/* * Authentication info. Opaque to client. */ struct opaque_auth { enum_t oa_flavor; /* flavor of auth */ caddr_t oa_base; /* address of more auth stuff */ u_int oa_length; /* not to exceed MAX_AUTH_BYTES */ }; /* * Auth handle, interface to client side authenticators. */ typedef struct { struct opaque_auth ah_cred; struct opaque_auth ah_verf; struct auth_ops { void (*ah_nextverf)(); int (*ah_marshal)(); /* nextverf & serialize */ int (*ah_validate)(); /* validate verifier */ int (*ah_refresh)(); /* refresh credentials */ void (*ah_destroy)(); /* destroy this structure */ } *ah_ops; caddr_t ah_private; } AUTH;
The CLIENT Structure¶
/* * Client rpc handle. * Created by individual implementations. * Client is responsible for initializing auth. */ typedef struct { AUTH *cl_auth; /* authenticator */ struct clnt_ops { enum clnt_stat (*cl_call)(); /* call remote procedure */ void (*cl_abort)(); /* abort a call */ void (*cl_geterr)(); /* get specific error code */ bool_t (*cl_freeres)(); /* frees results */ void (*cl_destroy)(); /* destroy this structure */ bool_t (*cl_control)(); /* the ioctl() of rpc */ } *cl_ops; caddr_t cl_private; /* private stuff */ char *cl_netid; /* network identifier */ char *cl_tp; /* device name */ } CLIENT;
The SVCXPRT structure¶
enum xprt_stat { XPRT_DIED, XPRT_MOREREQS, XPRT_IDLE }; /* * Server side transport handle */ typedef struct { int xp_fd; /* file descriptor for the server handle */ u_short xp_port; /* obsolete */ const struct xp_ops { bool_t (*xp_recv)(); /* receive incoming requests */ enum xprt_stat (*xp_stat)(); /* get transport status */ bool_t (*xp_getargs)(); /* get arguments */ bool_t (*xp_reply)(); /* send reply */ bool_t (*xp_freeargs)(); /* free mem allocated for args */ void (*xp_destroy)(); /* destroy this struct */ } *xp_ops; int xp_addrlen; /* length of remote addr. Obsolete */ struct sockaddr_in xp_raddr; /* Obsolete */ const struct xp_ops2 { bool_t (*xp_control)(); /* catch-all function */ } *xp_ops2; char *xp_tp; /* transport provider device name */ char *xp_netid; /* network identifier */ struct netbuf xp_ltaddr; /* local transport address */ struct netbuf xp_rtaddr; /* remote transport address */ struct opaque_auth xp_verf; /* raw response verifier */ caddr_t xp_p1; /* private: for use by svc ops */ caddr_t xp_p2; /* private: for use by svc ops */ caddr_t xp_p3; /* private: for use by svc lib */ int xp_type /* transport type */ } SVCXPRT;
The svc_reg structure¶
struct svc_req { rpcprog_t rq_prog; /* service program number */ rpcvers_t rq_vers; /* service protocol version */ rpcproc_t rq_proc; /* the desired procedure */ struct opaque_auth rq_cred; /* raw creds from the wire */ caddr_t rq_clntcred; /* read only cooked cred */ SVCXPRT *rq_xprt; /* associated transport */ };
The XDR structure¶
/* * XDR operations. * XDR_ENCODE causes the type to be encoded into the stream. * XDR_DECODE causes the type to be extracted from the stream. * XDR_FREE can be used to release the space allocated by an XDR_DECODE * request. */ enum xdr_op { XDR_ENCODE=0, XDR_DECODE=1, XDR_FREE=2 }; /* * This is the number of bytes per unit of external data. */ #define BYTES_PER_XDR_UNIT (4) #define RNDUP(x) ((((x) + BYTES_PER_XDR_UNIT - 1) / BYTES_PER_XDR_UNIT) \ * BYTES_PER_XDR_UNIT) /* * A xdrproc_t exists for each data type which is to be encoded or * decoded. The second argument to the xdrproc_t is a pointer to * an opaque pointer. The opaque pointer generally points to a * structure of the data type to be decoded. If this points to 0, * then the type routines should allocate dynamic storage of the * appropriate size and return it. * bool_t (*xdrproc_t)(XDR *, caddr_t *); */ typedef bool_t (*xdrproc_t)(); /* * The XDR handle. * Contains operation which is being applied to the stream, * an operations vector for the particular implementation */ typedef struct { enum xdr_op x_op; /* operation; fast additional param */ struct xdr_ops { bool_t (*x_getlong)(); /* get a long from underlying stream */ bool_t (*x_putlong)(); /* put a long to underlying stream */ bool_t (*x_getbytes)(); /* get bytes from underlying stream */ bool_t (*x_putbytes)(); /* put bytes to underlying stream */ u_int (*x_getpostn)(); /* returns bytes off from beginning */ bool_t (*x_setpostn)(); /* lets you reposition the stream */ long * (*x_inline)(); /* buf quick ptr to buffered data */ void (*x_destroy)(); /* free privates of this xdr_stream */ } *x_ops; caddr_t x_public; /* users' data */ caddr_t x_private; /* pointer to private data */ caddr_t x_base; /* private used for position info */ u_int x_handy; /* extra private word */ } XDR; /* * The netbuf structure. This structure is defined in <xti.h> on SysV * systems, but NetBSD / FreeBSD do not use XTI. * * Usually, buf will point to a struct sockaddr, and len and maxlen * will contain the length and maximum length of that socket address, * respectively. */ struct netbuf { unsigned int maxlen; unsigned int len; void *buf; }; /* * The format of the address and options arguments of the XTI t_bind call. * Only provided for compatibility, it should not be used other than * as an argument to svc_tli_create(). */ struct t_bind { struct netbuf addr; unsigned int qlen; };
Index to Routines¶
The following table lists RPC routines and the manual reference pages on which they are described:
- RPC Routine
- Manual Reference Page
auth_destroy
()- rpc_clnt_auth(3)
authdes_create
()- rpc_soc(3)
authnone_create
()- rpc_clnt_auth(3)
authsys_create
()- rpc_clnt_auth(3)
authsys_create_default
()- rpc_clnt_auth(3)
authunix_create
()- rpc_soc(3)
authunix_create_default
()- rpc_soc(3)
callrpc
()- rpc_soc(3)
clnt_broadcast
()- rpc_soc(3)
clnt_call
()- rpc_clnt_calls(3)
clnt_control
()- rpc_clnt_create(3)
clnt_create
()- rpc_clnt_create(3)
clnt_create_timed
()- rpc_clnt_create(3)
clnt_create_vers
()- rpc_clnt_create(3)
clnt_create_vers_timed
()- rpc_clnt_create(3)
clnt_destroy
()- rpc_clnt_create(3)
clnt_dg_create
()- rpc_clnt_create(3)
clnt_freeres
()- rpc_clnt_calls(3)
clnt_geterr
()- rpc_clnt_calls(3)
clnt_pcreateerror
()- rpc_clnt_create(3)
clnt_perrno
()- rpc_clnt_calls(3)
clnt_perror
()- rpc_clnt_calls(3)
clnt_raw_create
()- rpc_clnt_create(3)
clnt_spcreateerror
()- rpc_clnt_create(3)
clnt_sperrno
()- rpc_clnt_calls(3)
clnt_sperror
()- rpc_clnt_calls(3)
clnt_tli_create
()- rpc_clnt_create(3)
clnt_tp_create
()- rpc_clnt_create(3)
clnt_tp_create_timed
()- rpc_clnt_create(3)
clnt_udpcreate
()- rpc_soc(3)
clnt_vc_create
()- rpc_clnt_create(3)
clntraw_create
()- rpc_soc(3)
clnttcp_create
()- rpc_soc(3)
clntudp_bufcreate
()- rpc_soc(3)
get_myaddress
()- rpc_soc(3)
pmap_getmaps
()- rpc_soc(3)
pmap_getport
()- rpc_soc(3)
pmap_rmtcall
()- rpc_soc(3)
pmap_set
()- rpc_soc(3)
pmap_unset
()- rpc_soc(3)
registerrpc
()- rpc_soc(3)
rpc_broadcast
()- rpc_clnt_calls(3)
rpc_broadcast_exp
()- rpc_clnt_calls(3)
rpc_call
()- rpc_clnt_calls(3)
rpc_reg
()- rpc_svc_calls(3)
svc_create
()- rpc_svc_create(3)
svc_destroy
()- rpc_svc_create(3)
svc_dg_create
()- rpc_svc_create(3)
svc_dg_enablecache
()- rpc_svc_calls(3)
svc_fd_create
()- rpc_svc_create(3)
svc_fds
()- rpc_soc(3)
svc_freeargs
()- rpc_svc_reg(3)
svc_getargs
()- rpc_svc_reg(3)
svc_getcaller
()- rpc_soc(3)
svc_getreq
()- rpc_soc(3)
svc_getreqset
()- rpc_svc_calls(3)
svc_getrpccaller
()- rpc_svc_calls(3)
svc_kerb_reg
()- kerberos_rpc(3)
svc_raw_create
()- rpc_svc_create(3)
svc_reg
()- rpc_svc_calls(3)
svc_register
()- rpc_soc(3)
svc_run
()- rpc_svc_reg(3)
svc_sendreply
()- rpc_svc_reg(3)
svc_tli_create
()- rpc_svc_create(3)
svc_tp_create
()- rpc_svc_create(3)
svc_unreg
()- rpc_svc_calls(3)
svc_unregister
()- rpc_soc(3)
svc_vc_create
()- rpc_svc_create(3)
svcerr_auth
()- rpc_svc_err(3)
svcerr_decode
()- rpc_svc_err(3)
svcerr_noproc
()- rpc_svc_err(3)
svcerr_noprog
()- rpc_svc_err(3)
svcerr_progvers
()- rpc_svc_err(3)
svcerr_systemerr
()- rpc_svc_err(3)
svcerr_weakauth
()- rpc_svc_err(3)
svcfd_create
()- rpc_soc(3)
svcraw_create
()- rpc_soc(3)
svctcp_create
()- rpc_soc(3)
svcudp_bufcreate
()- rpc_soc(3)
svcudp_create
()- rpc_soc(3)
xdr_accepted_reply
()- rpc_xdr(3)
xdr_authsys_parms
()- rpc_xdr(3)
xdr_authunix_parms
()- rpc_soc(3)
xdr_callhdr
()- rpc_xdr(3)
xdr_callmsg
()- rpc_xdr(3)
xdr_opaque_auth
()- rpc_xdr(3)
xdr_rejected_reply
()- rpc_xdr(3)
xdr_replymsg
()- rpc_xdr(3)
xprt_register
()- rpc_svc_calls(3)
xprt_unregister
()- rpc_svc_calls(3)
FILES¶
- /etc/netconfig
AVAILABILITY¶
These functions are part of libtirpc.
SEE ALSO¶
getnetconfig(3), getnetpath(3), rpcbind(3), rpc_clnt_auth(3), rpc_clnt_calls(3), rpc_clnt_create(3), rpc_svc_calls(3), rpc_svc_create(3), rpc_svc_err(3), rpc_svc_reg(3), rpc_xdr(3), xdr(3), netconfig(5)
May 7, 1993 | Linux 5.14.0-427.18.1.el9_4.x86_64 |