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34 #include "krb5_locl.h"
36 RCSID("$Id: expand_hostname.c 23280 2008-06-23 03:26:18Z lha $");
38 static krb5_error_code
39 copy_hostname(krb5_context context,
40 const char *orig_hostname,
43 *new_hostname = strdup (orig_hostname);
44 if (*new_hostname == NULL) {
45 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
48 strlwr (*new_hostname);
53 * Try to make `orig_hostname' into a more canonical one in the newly
54 * allocated space returned in `new_hostname'.
57 krb5_error_code KRB5_LIB_FUNCTION
58 krb5_expand_hostname (krb5_context context,
59 const char *orig_hostname,
62 struct addrinfo *ai, *a, hints;
65 if ((context->flags & KRB5_CTX_F_DNS_CANONICALIZE_HOSTNAME) == 0)
66 return copy_hostname (context, orig_hostname, new_hostname);
68 memset (&hints, 0, sizeof(hints));
69 hints.ai_flags = AI_CANONNAME;
71 error = getaddrinfo (orig_hostname, NULL, &hints, &ai);
73 return copy_hostname (context, orig_hostname, new_hostname);
74 for (a = ai; a != NULL; a = a->ai_next) {
75 if (a->ai_canonname != NULL) {
76 *new_hostname = strdup (a->ai_canonname);
78 if (*new_hostname == NULL) {
79 krb5_set_error_message(context, ENOMEM,
80 "malloc: out of memory");
88 return copy_hostname (context, orig_hostname, new_hostname);
92 * handle the case of the hostname being unresolvable and thus identical
95 static krb5_error_code
96 vanilla_hostname (krb5_context context,
97 const char *orig_hostname,
103 ret = copy_hostname (context, orig_hostname, new_hostname);
106 strlwr (*new_hostname);
108 ret = krb5_get_host_realm (context, *new_hostname, realms);
110 free (*new_hostname);
117 * expand `hostname' to a name we believe to be a hostname in newly
118 * allocated space in `host' and return realms in `realms'.
121 krb5_error_code KRB5_LIB_FUNCTION
122 krb5_expand_hostname_realms (krb5_context context,
123 const char *orig_hostname,
127 struct addrinfo *ai, *a, hints;
129 krb5_error_code ret = 0;
131 if ((context->flags & KRB5_CTX_F_DNS_CANONICALIZE_HOSTNAME) == 0)
132 return vanilla_hostname (context, orig_hostname, new_hostname,
135 memset (&hints, 0, sizeof(hints));
136 hints.ai_flags = AI_CANONNAME;
138 error = getaddrinfo (orig_hostname, NULL, &hints, &ai);
140 return vanilla_hostname (context, orig_hostname, new_hostname,
143 for (a = ai; a != NULL; a = a->ai_next) {
144 if (a->ai_canonname != NULL) {
145 ret = copy_hostname (context, a->ai_canonname, new_hostname);
150 strlwr (*new_hostname);
151 ret = krb5_get_host_realm (context, *new_hostname, realms);
156 free (*new_hostname);
160 return vanilla_hostname (context, orig_hostname, new_hostname, realms);