unmunge(1) [debian man page]

UNMUNGE(1)						    MUNGE Uid 'N' Gid Emporium							UNMUNGE(1)

NAME

       unmunge - MUNGE credential decoder

SYNOPSIS

       unmunge [OPTION]...

DESCRIPTION

       The unmunge program validates a MUNGE credential (e.g., one created by the munge program).

       By  default, the credential is read from stdin and the metadata and payload are written to stdout.  When the metadata and payload are writ-
       ten to the same stream, they are separated by a blank line.

OPTIONS

       -h, --help
	      Display a summary of the command-line options.

       -L, --license
	      Display license information.

       -V, --version
	      Display version information.

       -i, --input file
	      Input the credential from the specified file.

       -n, --no-output
	      Discard all output.

       -m, --metadata file
	      Output metadata to the specified file.

       -o, --output file
	      Output the payload to the specified file.

       -k, --keys string
	      Specify a subset of metadata keys to output.  The keys are case-insensitive and delimited  by  whitespace,  commas,  semicolons,	or
	      periods -- as long as the string is treated as a single argument by the shell (e.g., enclosed by quotes).  If a subset is not speci-
	      fied, all available keys are selected by default.

       -K, --list-keys
	      Display a list of metadata keys.

       -S, --socket path
	      Specify the local domain socket for connecting with munged.

METADATA KEYS

       The following metadata keys are supported.

       STATUS The status of the credential decode operation.

       ENCODE_HOST
	      The address of the host on which the credential was encoded.

       ENCODE_TIME
	      The time at which the credential was encoded (according to the local clock of the host that encoded it).

       DECODE_TIME
	      The time at which the credential was decoded (according to the local clock of the host that decoded it).

       TTL    The time-to-live value (in seconds) placed within the credential.

       CIPHER The cipher type used to encode the credential.

       MAC    The MAC type used to encode the credential.

       ZIP    The compression type used to encode the credential.

       UID    The user ID of the process that encoded the credential.

       GID    The group ID of the process that encoded the credential.

       UID_RESTRICTION
	      The user ID restriction placed within the credential.

       GID_RESTRICTION
	      The group ID restriction placed within the credential.

       LENGTH The length (in bytes) of the payload.

EXIT STATUS

       The unmunge program returns an exit code corresponding to the return code of munge_decode().  On success, it returns a zero exit code which
       signifies the credential is valid.  On error, it prints an error message to stderr and returns a non-zero exit code.

AUTHOR

       Chris Dunlap <cdunlap@llnl.gov>

COPYRIGHT

       Copyright (C) 2007-2011 Lawrence Livermore National Security, LLC.
       Copyright (C) 2002-2007 The Regents of the University of California.

       MUNGE 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 3 of the License, or (at your option) any later version.

       Additionally for the MUNGE library (libmunge), 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 3 of the License, or (at your option) any later version.

SEE ALSO

       munge(1), remunge(1), munge(3), munge_ctx(3), munge_enum(3), munge(7), munged(8).

       http://munge.googlecode.com/

munge-0.5.10							    2011-02-25								UNMUNGE(1)

MUNGE(3)						    MUNGE Uid 'N' Gid Emporium							  MUNGE(3)

NAME

       munge_encode, munge_decode, munge_strerror - MUNGE core functions

SYNOPSIS

       #include <munge.h>

       munge_err_t munge_encode (char **cred, munge_ctx_t ctx,
				 const void *buf, int len);

       munge_err_t munge_decode (const char *cred, munge_ctx_t ctx,
				 void **buf, int *len, uid_t *uid, gid_t *gid);

       const char * munge_strerror (munge_err_t e);

       cc ... -lmunge

DESCRIPTION

       The  munge_encode()  function  creates  a  credential  contained in a NUL-terminated base64 string.  A payload specified by a buffer buf of
       length len can be encapsulated in as well.  If the MUNGE context ctx is NULL, the default context will be used.	A pointer to the resulting
       credential is returned via cred; on error, it is set to NULL.  The caller is responsible for freeing the memory referenced by cred.

       The  munge_decode()  function  validates  the NUL-terminated credential cred.  If the MUNGE context ctx is not NULL, it will be set to that
       used to encode the credential.  If buf and len are not NULL, memory will be allocated for the encapsulated payload,  buf  will  be  set	to
       point  to this data, and len will be set to its length.	An additional NUL character will be appended to this payload data but not included
       in its length.  If no payload exists, buf will be set to NULL and len will be set to 0.	For  certain  errors  (i.e.,  EMUNGE_CRED_EXPIRED,
       EMUNGE_CRED_REWOUND, EMUNGE_CRED_REPLAYED), payload memory will still be allocated if necessary.  The caller is responsible for freeing the
       memory referenced by buf.  If uid or gid is not NULL, they will be set to the UID/GID of the process that created the credential.

       The munge_strerror() function returns a descriptive text string describing the MUNGE error number e.

RETURN VALUE

       The munge_encode() and munge_decode() functions return EMUNGE_SUCCESS on success, or a MUNGE error otherwise.  If a MUNGE context was used,
       it may contain a more detailed error message accessible via munge_ctx_strerror().

       The  munge_strerror()  function	returns a pointer to a NUL-terminated constant text string; this string should not be freed or modified by
       the caller.

ERRORS

       EMUNGE_SUCCESS
	      Success.

       EMUNGE_SNAFU
	      Internal error.

       EMUNGE_BAD_ARG
	      Invalid argument.

       EMUNGE_BAD_LENGTH
	      Exceeded the maximum message length as specified by the munged configuration.

       EMUNGE_OVERFLOW
	      Exceeded the maximum length of a buffer.

       EMUNGE_NO_MEMORY
	      Unable to allocate the requisite memory.

       EMUNGE_SOCKET
	      Unable to communicate with the daemon on the domain socket.

       EMUNGE_BAD_CRED
	      The credential does not match the specified format.

       EMUNGE_BAD_VERSION
	      The credential contains an unsupported version number.

       EMUNGE_BAD_CIPHER
	      The credential contains an unsupported cipher type.

       EMUNGE_BAD_MAC
	      The credential contains an unsupported MAC type.

       EMUNGE_BAD_ZIP
	      The credential contains an unsupported compression type.

       EMUNGE_BAD_REALM
	      The credential contains an unrecognized security realm.

       EMUNGE_CRED_INVALID
	      The credential is invalid.  This means the credential could not be successfully decoded.	More than likely, the secret keys  on  the
	      encoding and decoding hosts do not match.  Another possibility is that the credential has been altered since it was encoded.

       EMUNGE_CRED_EXPIRED
	      The credential has expired.  This means more than TTL seconds have elapsed since the credential was encoded.  Another possibility is
	      that the clocks on the encoding and decoding hosts are out of sync.

       EMUNGE_CRED_REWOUND
	      The credential appears to have been encoded at some point in the future.	This means the clock on the decoding host is  slower  than
	      that  of	the  encoding host by more than the allowable clock skew.  More than likely, the clocks on the encoding and decoding hosts
	      are out of sync.

       EMUNGE_CRED_REPLAYED
	      The credential has been previously decoded on this host.

       EMUNGE_CRED_UNAUTHORIZED
	      The client is not authorized to decode the credential based upon the effective user and/or group ID of the process.

EXAMPLE

       The following example program illustrates the use of a MUNGE credential to ascertain the effective  user  and  group  ID  of  the  encoding
       process.

       #include <stdio.h>		       /* for printf() */
       #include <stdlib.h>		       /* for exit() & free() */
       #include <unistd.h>		       /* for uid_t & gid_t */
       #include <munge.h>

       int
       main (int argc, char *argv[])
       {
	   char        *cred;
	   munge_err_t	err;
	   uid_t	uid;
	   gid_t	gid;

	   err = munge_encode (&cred, NULL, NULL, 0);

	   if (err != EMUNGE_SUCCESS) {
	       fprintf (stderr, "ERROR: %s
", munge_strerror (err));
	       exit (1);
	   }
	   err = munge_decode (cred, NULL, NULL, NULL, &uid, &gid);

	   if (err != EMUNGE_SUCCESS) {
	       fprintf (stderr, "ERROR: %s
", munge_strerror (err));
	       exit (1);
	   }
	   printf ("uid=%d gid=%d
", uid, gid);
	   free (cred);
	   exit (0);
       }

NOTES

       Both  munge_encode()  and munge_decode() may allocate memory that the caller is responsible for freeing.  Failure to do so will result in a
       memory leak.

AUTHOR

       Chris Dunlap <cdunlap@llnl.gov>

COPYRIGHT

       Copyright (C) 2007-2011 Lawrence Livermore National Security, LLC.
       Copyright (C) 2002-2007 The Regents of the University of California.

       MUNGE 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 3 of the License, or (at your option) any later version.

       Additionally  for  the  MUNGE library (libmunge), 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 3 of the License, or (at your option) any later version.

SEE ALSO

       munge(1), remunge(1), unmunge(1), munge_ctx(3), munge_enum(3), munge(7), munged(8).

       http://munge.googlecode.com/

munge-0.5.10							    2011-02-25								  MUNGE(3)