Add implementations of kname_parse and kname_unparse to afs._pts.

[invirt/packages/python-afs.git] / afs / _pts.pyx

diff --git a/afs/_pts.pyx b/afs/_pts.pyx
index bef7139..2ebc064 100644 (file)
--- a/afs/_pts.pyx
+++ b/afs/_pts.pyx
@@ -1,5 +1,6 @@
 from afs cimport *
 from afs import pyafs_error
+import re
 
 cdef import from "afs/ptuser.h":
     enum:
@@ -71,6 +72,27 @@ cdef import from "afs/pterror.h":
     enum:
         PRNOENT
 
+cdef import from "krb5/krb5.h":
+    struct _krb5_context:
+        pass
+    struct krb5_principal_data:
+        pass
+
+    ctypedef _krb5_context * krb5_context
+    ctypedef krb5_principal_data * krb5_principal
+
+    ctypedef long krb5_int32
+    ctypedef krb5_int32 krb5_error_code
+    krb5_error_code krb5_init_context(krb5_context *)
+    krb5_error_code krb5_parse_name(krb5_context, char *, krb5_principal *)
+    krb5_error_code krb5_unparse_name(krb5_context, krb5_principal, char **)
+    krb5_error_code krb5_524_conv_principal(krb5_context, krb5_principal, char *, char *, char *)
+    krb5_error_code krb5_425_conv_principal(krb5_context, char *, char *, char *, krb5_principal *)
+    krb5_error_code krb5_get_host_realm(krb5_context, char *, char ***)
+    void krb5_free_host_realm(krb5_context, char **)
+    void krb5_free_principal(krb5_context, krb5_principal)
+    void krb5_free_context(krb5_context)
+
 cdef class PTEntry:
     cdef public afs_int32 flags
     cdef public afs_int32 id
@@ -117,6 +139,28 @@ cdef int _ptentry_to_c(prcheckentry * c_entry, PTEntry p_entry) except -1:
     strncpy(c_entry.name, p_entry.name, sizeof(c_entry.name))
     return 0
 
+cdef object kname_re = re.compile(r'^([^.].*?)(?<!\\)(?:\.(.*?))?(?<!\\)@([^@]*)$')
+
+cdef object kname_parse(fullname):
+    """Parse a krb4-style principal into a name, instance, and realm."""
+    cdef object re_match = kname_re.match(fullname)
+    if not re_match:
+        return None
+    else:
+        princ = re_match.groups()
+        return tuple([re.sub(r'\\(.)', r'\1', x) if x else x for x in princ])
+
+cdef object kname_unparse(name, inst, realm):
+    """Unparse a name, instance, and realm into a single krb4
+    principal string."""
+    name = re.sub('r([.\\@])', r'\\\1', name)
+    inst = re.sub('r([.\\@])', r'\\\1', inst)
+    realm = re.sub(r'([\\@])', r'\\\1', realm)
+    if inst:
+        return '%s.%s@%s' % (name, inst, realm)
+    else:
+        return '%s@%s' % (name, realm)
+
 cdef class PTS:
     """
     A PTS object is essentially a handle to talk to the server in a
@@ -131,14 +175,20 @@ cdef class PTS:
       - 2: fail if an authenticated connection can't be established
       - 3: same as 2, plus encrypt all traffic to the protection
         server
+
+    The realm attribute is the Kerberos realm against which this cell
+    authenticates.
     """
     cdef ubik_client * client
     cdef readonly object cell
+    cdef readonly object realm
 
     def __cinit__(self, cell=None, sec=1):
         cdef afs_int32 code
         cdef afsconf_dir *cdir
         cdef afsconf_cell info
+        cdef krb5_context context
+        cdef char ** hrealms = NULL
         cdef char * c_cell
         cdef ktc_principal prin
         cdef ktc_token token
@@ -167,6 +217,14 @@ cdef class PTS:
         code = afsconf_GetCellInfo(cdir, c_cell, "afsprot", &info)
         pyafs_error(code)
 
+        code = krb5_init_context(&context)
+        pyafs_error(code)
+        code = krb5_get_host_realm(context, info.hostName[0], &hrealms)
+        pyafs_error(code)
+        self.realm = hrealms[0]
+        krb5_free_host_realm(context, hrealms)
+        krb5_free_context(context)
+
         self.cell = info.name
 
         if sec > 0: