KRB5_AUTH_CONTEXT(3) BSD Library Functions Manual KRB5_AUTH_CONTEXT(3)NAME
krb5_auth_con_addflags, krb5_auth_con_free, krb5_auth_con_genaddrs,
krb5_auth_con_generatelocalsubkey, krb5_auth_con_getaddrs,
krb5_auth_con_getauthenticator, krb5_auth_con_getflags,
krb5_auth_con_getkey, krb5_auth_con_getlocalsubkey,
krb5_auth_con_getrcache, krb5_auth_con_getremotesubkey,
krb5_auth_con_getuserkey, krb5_auth_con_init, krb5_auth_con_initivector,
krb5_auth_con_removeflags, krb5_auth_con_setaddrs,
krb5_auth_con_setaddrs_from_fd, krb5_auth_con_setflags,
krb5_auth_con_setivector, krb5_auth_con_setkey,
krb5_auth_con_setlocalsubkey, krb5_auth_con_setrcache,
krb5_auth_con_setremotesubkey, krb5_auth_con_setuserkey,
krb5_auth_context, krb5_auth_getcksumtype, krb5_auth_getkeytype,
krb5_auth_getlocalseqnumber, krb5_auth_getremoteseqnumber,
krb5_auth_setcksumtype, krb5_auth_setkeytype,
krb5_auth_setlocalseqnumber, krb5_auth_setremoteseqnumber,
krb5_free_authenticator — manage authentication on connection level
LIBRARY
Kerberos 5 Library (libkrb5, -lkrb5)
SYNOPSIS
#include <krb5.h>
krb5_error_code
krb5_auth_con_init(krb5_context context,
krb5_auth_context *auth_context);
void
krb5_auth_con_free(krb5_context context, krb5_auth_context auth_context);
krb5_error_code
krb5_auth_con_setflags(krb5_context context,
krb5_auth_context auth_context, int32_t flags);
krb5_error_code
krb5_auth_con_getflags(krb5_context context,
krb5_auth_context auth_context, int32_t *flags);
krb5_error_code
krb5_auth_con_addflags(krb5_context context,
krb5_auth_context auth_context, int32_t addflags, int32_t *flags);
krb5_error_code
krb5_auth_con_removeflags(krb5_context context,
krb5_auth_context auth_context, int32_t removelags, int32_t *flags);
krb5_error_code
krb5_auth_con_setaddrs(krb5_context context,
krb5_auth_context auth_context, krb5_address *local_addr,
krb5_address *remote_addr);
krb5_error_code
krb5_auth_con_getaddrs(krb5_context context,
krb5_auth_context auth_context, krb5_address **local_addr,
krb5_address **remote_addr);
krb5_error_code
krb5_auth_con_genaddrs(krb5_context context,
krb5_auth_context auth_context, int fd, int flags);
krb5_error_code
krb5_auth_con_setaddrs_from_fd(krb5_context context,
krb5_auth_context auth_context, void *p_fd);
krb5_error_code
krb5_auth_con_getkey(krb5_context context,
krb5_auth_context auth_context, krb5_keyblock **keyblock);
krb5_error_code
krb5_auth_con_getlocalsubkey(krb5_context context,
krb5_auth_context auth_context, krb5_keyblock **keyblock);
krb5_error_code
krb5_auth_con_getremotesubkey(krb5_context context,
krb5_auth_context auth_context, krb5_keyblock **keyblock);
krb5_error_code
krb5_auth_con_generatelocalsubkey(krb5_context context,
krb5_auth_context auth_context, krb5_keyblock, *key");
krb5_error_code
krb5_auth_con_initivector(krb5_context context,
krb5_auth_context auth_context);
krb5_error_code
krb5_auth_con_setivector(krb5_context context,
krb5_auth_context *auth_context, krb5_pointer ivector);
void
krb5_free_authenticator(krb5_context context,
krb5_authenticator *authenticator);
DESCRIPTION
The krb5_auth_context structure holds all context related to an authenti‐
cated connection, in a similar way to krb5_context that holds the context
for the thread or process. krb5_auth_context is used by various func‐
tions that are directly related to authentication between the
server/client. Example of data that this structure contains are various
flags, addresses of client and server, port numbers, keyblocks (and sub‐
keys), sequence numbers, replay cache, and checksum-type.
krb5_auth_con_init() allocates and initializes the krb5_auth_context
structure. Default values can be changed with
krb5_auth_con_setcksumtype() and krb5_auth_con_setflags(). The
auth_context structure must be freed by krb5_auth_con_free().
krb5_auth_con_getflags(), krb5_auth_con_setflags(),
krb5_auth_con_addflags() and krb5_auth_con_removeflags() gets and modi‐
fies the flags for a krb5_auth_context structure. Possible flags to set
are:
KRB5_AUTH_CONTEXT_DO_SEQUENCE
Generate and check sequence-number on each packet.
KRB5_AUTH_CONTEXT_DO_TIME
Check timestamp on incoming packets.
KRB5_AUTH_CONTEXT_RET_SEQUENCE, KRB5_AUTH_CONTEXT_RET_TIME
Return sequence numbers and time stamps in the outdata parame‐
ters.
KRB5_AUTH_CONTEXT_CLEAR_FORWARDED_CRED
will force krb5_get_forwarded_creds() and krb5_fwd_tgt_creds() to
create unencrypted ) ENCTYPE_NULL) credentials. This is for use
with old MIT server and JAVA based servers as they can't handle
encrypted KRB-CRED. Note that sending such KRB-CRED is clear
exposes crypto keys and tickets and is insecure, make sure the
packet is encrypted in the protocol. krb5_rd_cred(3),
krb5_rd_priv(3), krb5_rd_safe(3), krb5_mk_priv(3) and
krb5_mk_safe(3). Setting this flag requires that parameter to be
passed to these functions.
The flags KRB5_AUTH_CONTEXT_DO_TIME also modifies the behavior
the function krb5_get_forwarded_creds() by removing the timestamp
in the forward credential message, this have backward compatibil‐
ity problems since not all versions of the heimdal supports time‐
less credentional messages. Is very useful since it always the
sender of the message to cache forward message and thus avoiding
a round trip to the KDC for each time a credential is forwarded.
The same functionality can be obtained by using address-less
tickets.
krb5_auth_con_setaddrs(), krb5_auth_con_setaddrs_from_fd() and
krb5_auth_con_getaddrs() gets and sets the addresses that are checked
when a packet is received. It is mandatory to set an address for the
remote host. If the local address is not set, it iss deduced from the
underlaying operating system. krb5_auth_con_getaddrs() will call
krb5_free_address() on any address that is passed in local_addr or
remote_addr. krb5_auth_con_setaddr() allows passing in a NULL pointer as
local_addr and remote_addr, in that case it will just not set that
address.
krb5_auth_con_setaddrs_from_fd() fetches the addresses from a file
descriptor.
krb5_auth_con_genaddrs() fetches the address information from the given
file descriptor fd depending on the bitmap argument flags.
Possible values on flags are:
KRB5_AUTH_CONTEXT_GENERATE_LOCAL_ADDR
fetches the local address from fd.
KRB5_AUTH_CONTEXT_GENERATE_REMOTE_ADDR
fetches the remote address from fd.
krb5_auth_con_setkey(), krb5_auth_con_setuserkey() and
krb5_auth_con_getkey() gets and sets the key used for this auth context.
The keyblock returned by krb5_auth_con_getkey() should be freed with
krb5_free_keyblock(). The keyblock send into krb5_auth_con_setkey() is
copied into the krb5_auth_context, and thus no special handling is
needed. NULL is not a valid keyblock to krb5_auth_con_setkey().
krb5_auth_con_setuserkey() is only useful when doing user to user authen‐
tication. krb5_auth_con_setkey() is equivalent to
krb5_auth_con_setuserkey().
krb5_auth_con_getlocalsubkey(), krb5_auth_con_setlocalsubkey(),
krb5_auth_con_getremotesubkey() and krb5_auth_con_setremotesubkey() gets
and sets the keyblock for the local and remote subkey. The keyblock
returned by krb5_auth_con_getlocalsubkey() and
krb5_auth_con_getremotesubkey() must be freed with krb5_free_keyblock().
krb5_auth_setcksumtype() and krb5_auth_getcksumtype() sets and gets the
checksum type that should be used for this connection.
krb5_auth_con_generatelocalsubkey() generates a local subkey that have
the same encryption type as key.
krb5_auth_getremoteseqnumber()krb5_auth_setremoteseqnumber(),
krb5_auth_getlocalseqnumber() and krb5_auth_setlocalseqnumber() gets and
sets the sequence-number for the local and remote sequence-number
counter.
krb5_auth_setkeytype() and krb5_auth_getkeytype() gets and gets the key‐
type of the keyblock in krb5_auth_context.
krb5_auth_con_getauthenticator() Retrieves the authenticator that was
used during mutual authentication. The authenticator returned should be
freed by calling krb5_free_authenticator().
krb5_auth_con_getrcache() and krb5_auth_con_setrcache() gets and sets the
replay-cache.
krb5_auth_con_initivector() allocates memory for and zeros the initial
vector in the auth_context keyblock.
krb5_auth_con_setivector() sets the i_vector portion of auth_context to
ivector.
krb5_free_authenticator() free the content of authenticator and
authenticator itself.
SEE ALSOkrb5_context(3), kerberos(8)HEIMDAL May 17, 2005 HEIMDAL
