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nfsclnt(2) [osx man page]

NFSCLNT(2)						      BSD System Calls Manual							NFSCLNT(2)

NAME
nfsclnt -- NFS client services SYNOPSIS
#include <unistd.h> #include <nfs/nfs.h> int nfsclnt(int flags, void *argstructp); DESCRIPTION
The nfsclnt() function is used by the NFS client daemons to pass information into and out of the kernel. The flags argument consists of sev- eral bits that show what action is to be taken once in the kernel and the argstructp points to any corresponding data that the action may require. rpc.lockd(8) calls nfsclnt() with the flag NFSCLNT_LOCKDANS and a pointer to a struct lockd_ans { int la_version; /* lockd_ans version */ int la_errno; /* return status */ u_int64_t la_xid; /* unique message transaction ID */ int la_flags; /* answer flags */ pid_t la_pid; /* pid of lock requester/owner */ off_t la_start; /* lock starting offset */ off_t la_len; /* lock length */ int la_fh_len; /* The file handle length. */ u_int8_t la_fh[NFSV3_MAX_FH_SIZE];/* The file handle. */ }; to pass the response to an NFS file locking request back into the kernel. RETURN VALUES
Upon successful completion, a value of 0 is returned. Otherwise, -1 is returned and the global variable errno is set to specify the error. ERRORS
[EPERM] The caller is not the super-user. [EINVAL] The action specified by the flags argument was not valid. [EFAULT] argstructp points to an invalid address. [EPIPE] The response doesn't match any currently-outstanding lock request. SEE ALSO
rpc.lockd(8) BUGS
The nfsclnt system call is designed specifically for the NFS client daemons and as such is specific to their requirements. Several fields of the argument structures are assumed to be valid, such that nfsclnt must be used with extreme care. BSD
January 9, 2007 BSD

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NFSSVC(2)						      BSD System Calls Manual							 NFSSVC(2)

NAME
nfssvc -- NFS services LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <sys/param.h> #include <sys/mount.h> #include <sys/time.h> #include <nfs/rpcv2.h> #include <nfsserver/nfs.h> #include <unistd.h> int nfssvc(int flags, void *argstructp); DESCRIPTION
The nfssvc() system call is used by the NFS daemons to pass information into and out of the kernel and also to enter the kernel as a server daemon. The flags argument consists of several bits that show what action is to be taken once in the kernel and the argstructp points to one of three structures depending on which bits are set in flags. On the client side, nfsiod(8) calls nfssvc() with the flags argument set to NFSSVC_BIOD and argstructp set to NULL to enter the kernel as a block I/O server daemon. For NQNFS, mount_nfs(8) calls nfssvc() with the NFSSVC_MNTD flag, optionally or'd with the flags NFSSVC_GOTAUTH and NFSSVC_AUTHINFAIL along with a pointer to a struct nfsd_cargs { char *ncd_dirp; /* Mount dir path */ uid_t ncd_authuid; /* Effective uid */ int ncd_authtype; /* Type of authenticator */ int ncd_authlen; /* Length of authenticator string */ u_char *ncd_authstr; /* Authenticator string */ int ncd_verflen; /* and the verifier */ u_char *ncd_verfstr; NFSKERBKEY_T ncd_key; /* Session key */ }; structure. The initial call has only the NFSSVC_MNTD flag set to specify service for the mount point. If the mount point is using Kerberos, then the mount_nfs(8) utility will return from nfssvc() with errno == ENEEDAUTH whenever the client side requires an ``rcmd'' authentication ticket for the user. The mount_nfs(8) utility will attempt to get the Kerberos ticket, and if successful will call nfssvc() with the flags NFSSVC_MNTD and NFSSVC_GOTAUTH after filling the ticket into the ncd_authstr field and setting the ncd_authlen and ncd_authtype fields of the nfsd_cargs structure. If mount_nfs(8) failed to get the ticket, nfssvc() will be called with the flags NFSSVC_MNTD, NFSSVC_GOTAUTH and NFSSVC_AUTHINFAIL to denote a failed authentication attempt. On the server side, nfssvc() is called with the flag NFSSVC_NFSD and a pointer to a struct nfsd_srvargs { struct nfsd *nsd_nfsd; /* Pointer to in kernel nfsd struct */ uid_t nsd_uid; /* Effective uid mapped to cred */ uint32_t nsd_haddr; /* Ip address of client */ struct ucred nsd_cr; /* Cred. uid maps to */ int nsd_authlen; /* Length of auth string (ret) */ u_char *nsd_authstr; /* Auth string (ret) */ int nsd_verflen; /* and the verifier */ u_char *nsd_verfstr; struct timeval nsd_timestamp; /* timestamp from verifier */ uint32_t nsd_ttl; /* credential ttl (sec) */ NFSKERBKEY_T nsd_key; /* Session key */ }; to enter the kernel as an nfsd(8) daemon. Whenever an nfsd(8) daemon receives a Kerberos authentication ticket, it will return from nfssvc() with errno == ENEEDAUTH. The nfsd(8) utility will attempt to authenticate the ticket and generate a set of credentials on the server for the ``user id'' specified in the field nsd_uid. This is done by first authenticating the Kerberos ticket and then mapping the Kerberos principal to a local name and getting a set of credentials for that user via getpwnam(3) and getgrouplist(3). If successful, the nfsd(8) utility will call nfssvc() with the NFSSVC_NFSD and NFSSVC_AUTHIN flags set to pass the credential mapping in nsd_cr into the kernel to be cached on the server socket for that client. If the authentication failed, nfsd(8) calls nfssvc() with the flags NFSSVC_NFSD and NFSSVC_AUTHINFAIL to denote an authentication failure. The master nfsd(8) server daemon calls nfssvc() with the flag NFSSVC_ADDSOCK and a pointer to a struct nfsd_args { int sock; /* Socket to serve */ caddr_t name; /* Client address for connection based sockets */ int namelen;/* Length of name */ }; to pass a server side NFS socket into the kernel for servicing by the nfsd(8) daemons. RETURN VALUES
Normally nfssvc() does not return unless the server is terminated by a signal when a value of 0 is returned. Otherwise, -1 is returned and the global variable errno is set to specify the error. ERRORS
[ENEEDAUTH] This special error value is really used for authentication support, particularly Kerberos, as explained above. [EPERM] The caller is not the super-user. SEE ALSO
mount_nfs(8), nfsd(8), nfsiod(8) HISTORY
The nfssvc() system call first appeared in 4.4BSD. BUGS
The nfssvc() system call is designed specifically for the NFS support daemons and as such is specific to their requirements. It should really return values to indicate the need for authentication support, since ENEEDAUTH is not really an error. Several fields of the argument structures are assumed to be valid and sometimes to be unchanged from a previous call, such that nfssvc() must be used with extreme care. BSD
June 9, 1993 BSD
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