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34 #include "krb5_locl.h"
36 RCSID("$Id: expand_hostname.c 22229 2007-12-08 21:40:59Z 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_string(context, "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_string(context, "malloc: out of memory");
87 return copy_hostname (context, orig_hostname, new_hostname);
91 * handle the case of the hostname being unresolvable and thus identical
94 static krb5_error_code
95 vanilla_hostname (krb5_context context,
96 const char *orig_hostname,
102 ret = copy_hostname (context, orig_hostname, new_hostname);
105 strlwr (*new_hostname);
107 ret = krb5_get_host_realm (context, *new_hostname, realms);
109 free (*new_hostname);
116 * expand `hostname' to a name we believe to be a hostname in newly
117 * allocated space in `host' and return realms in `realms'.
120 krb5_error_code KRB5_LIB_FUNCTION
121 krb5_expand_hostname_realms (krb5_context context,
122 const char *orig_hostname,
126 struct addrinfo *ai, *a, hints;
128 krb5_error_code ret = 0;
130 if ((context->flags & KRB5_CTX_F_DNS_CANONICALIZE_HOSTNAME) == 0)
131 return vanilla_hostname (context, orig_hostname, new_hostname,
134 memset (&hints, 0, sizeof(hints));
135 hints.ai_flags = AI_CANONNAME;
137 error = getaddrinfo (orig_hostname, NULL, &hints, &ai);
139 return vanilla_hostname (context, orig_hostname, new_hostname,
142 for (a = ai; a != NULL; a = a->ai_next) {
143 if (a->ai_canonname != NULL) {
144 ret = copy_hostname (context, a->ai_canonname, new_hostname);
149 strlwr (*new_hostname);
150 ret = krb5_get_host_realm (context, *new_hostname, realms);
155 free (*new_hostname);
159 return vanilla_hostname (context, orig_hostname, new_hostname, realms);