aboutsummaryrefslogtreecommitdiff
path: root/portable/krb5-extra.c
blob: c8309a4640e65e36948ecf91a32953ff4429ff2b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
/*
 * Portability glue functions for Kerberos.
 *
 * This file provides definitions of the interfaces that portable/krb5.h
 * ensures exist if the function wasn't available in the Kerberos libraries.
 * Everything in this file will be protected by #ifndef.  If the native
 * Kerberos libraries are fully capable, this file will be skipped.
 *
 * The canonical version of this file is maintained in the rra-c-util package,
 * which can be found at <http://www.eyrie.org/~eagle/software/rra-c-util/>.
 *
 * Written by Russ Allbery <eagle@eyrie.org>
 *
 * The authors hereby relinquish any claim to any copyright that they may have
 * in this work, whether granted under contract or by operation of law or
 * international treaty, and hereby commit to the public, at large, that they
 * shall not, at any time in the future, seek to enforce any copyright in this
 * work against any person or entity, or prevent any person or entity from
 * copying, publishing, distributing or creating derivative works of this
 * work.
 */

#include <config.h>
#include <portable/krb5.h>
#include <portable/macros.h>
#include <portable/system.h>

#include <errno.h>

/* Figure out what header files to include for error reporting. */
#if !defined(HAVE_KRB5_GET_ERROR_MESSAGE) && !defined(HAVE_KRB5_GET_ERR_TEXT)
# if !defined(HAVE_KRB5_GET_ERROR_STRING)
#  if defined(HAVE_IBM_SVC_KRB5_SVC_H)
#   include <ibm_svc/krb5_svc.h>
#  elif defined(HAVE_ET_COM_ERR_H)
#   include <et/com_err.h>
#  elif defined(HAVE_KERBEROSV5_COM_ERR_H)
#   include <kerberosv5/com_err.h>
#  else
#   include <com_err.h>
#  endif
# endif
#endif

/* Used for unused parameters to silence gcc warnings. */
#define UNUSED __attribute__((__unused__))

/*
 * This string is returned for unknown error messages.  We use a static
 * variable so that we can be sure not to free it.
 */
static const char error_unknown[] = "unknown error";


#ifndef HAVE_KRB5_GET_ERROR_MESSAGE
/*
 * Given a Kerberos error code, return the corresponding error.  Prefer the
 * Kerberos interface if available since it will provide context-specific
 * error information, whereas the error_message() call will only provide a
 * fixed message.
 */
const char *
krb5_get_error_message(krb5_context ctx UNUSED, krb5_error_code code UNUSED)
{
    const char *msg = NULL;

# if defined(HAVE_KRB5_GET_ERROR_STRING)
    msg = krb5_get_error_string(ctx);
# elif defined(HAVE_KRB5_GET_ERR_TEXT)
    msg = krb5_get_err_text(ctx, code);
# elif defined(HAVE_KRB5_SVC_GET_MSG)
    krb5_svc_get_msg(code, (char **) &msg);
# else
    msg = error_message(code);
# endif
    if (msg == NULL)
        return error_unknown;
    else
        return msg;
}
#endif /* !HAVE_KRB5_GET_ERROR_MESSAGE */


#ifndef HAVE_KRB5_FREE_ERROR_MESSAGE
/*
 * Free an error string if necessary.  If we returned a static string, make
 * sure we don't free it.
 *
 * This code assumes that the set of implementations that have
 * krb5_free_error_message is a subset of those with krb5_get_error_message.
 * If this assumption ever breaks, we may call the wrong free function.
 */
void
krb5_free_error_message(krb5_context ctx UNUSED, const char *msg)
{
    if (msg == error_unknown)
        return;
# if defined(HAVE_KRB5_GET_ERROR_STRING)
    krb5_free_error_string(ctx, (char *) msg);
# elif defined(HAVE_KRB5_SVC_GET_MSG)
    krb5_free_string(ctx, (char *) msg);
# endif
}
#endif /* !HAVE_KRB5_FREE_ERROR_MESSAGE */


#ifndef HAVE_KRB5_GET_INIT_CREDS_OPT_ALLOC
/*
 * Allocate and initialize a krb5_get_init_creds_opt struct.  This code
 * assumes that an all-zero bit pattern will create a NULL pointer.
 */
krb5_error_code
krb5_get_init_creds_opt_alloc(krb5_context ctx UNUSED,
                              krb5_get_init_creds_opt **opts)
{
    *opts = calloc(1, sizeof(krb5_get_init_creds_opt));
    if (*opts == NULL)
        return errno;
    krb5_get_init_creds_opt_init(*opts);
    return 0;
}
#endif /* !HAVE_KRB5_GET_INIT_CREDS_OPT_ALLOC */


#ifndef HAVE_KRB5_PRINCIPAL_GET_REALM
/*
 * Return the realm of a principal as a const char *.
 */
const char *
krb5_principal_get_realm(krb5_context ctx UNUSED, krb5_const_principal princ)
{
    const krb5_data *data;

    data = krb5_princ_realm(ctx, princ);
    if (data == NULL || data->data == NULL)
        return NULL;
    return data->data;
}
#endif /* !HAVE_KRB5_PRINCIPAL_GET_REALM */