s4:dsdb: Switch to using smb_krb5_princ_component()

This function has the handy feature of being able to be called twice in
succession without mysteriously breaking your code. Now, doesn’t that
sound useful?

Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>

diff --git a/source4/dsdb/samdb/cracknames.c b/source4/dsdb/samdb/cracknames.c
index 123d519b69fe62d6194dda2af170c0a9bd49af1a..1301b5ad589805c957ea86bc48b9d27b32f162c0 100644 (file)
--- a/source4/dsdb/samdb/cracknames.c
+++ b/source4/dsdb/samdb/cracknames.c
@@ -195,7 +195,7 @@ static WERROR DsCrackNameSPNAlias(struct ldb_context *sam_ctx, TALLOC_CTX *mem_c
        WERROR wret;
        krb5_error_code ret;
        krb5_principal principal;
-       const krb5_data *component;
+       krb5_data component;
        const char *service, *dns_name;
        char *new_service;
        char *new_princ;
@@ -213,18 +213,22 @@ static WERROR DsCrackNameSPNAlias(struct ldb_context *sam_ctx, TALLOC_CTX *mem_c
 
        /* grab cifs/, http/ etc */
 
-       /* This is checked for in callers, but be safe */
-       if (krb5_princ_size(smb_krb5_context->krb5_context, principal) < 2) {
+       ret = smb_krb5_princ_component(smb_krb5_context->krb5_context,
+                                      principal, 0, &component);
+       if (ret) {
+               info1->status = DRSUAPI_DS_NAME_STATUS_NOT_FOUND;
+               krb5_free_principal(smb_krb5_context->krb5_context, principal);
+               return WERR_OK;
+       }
+       service = (const char *)component.data;
+       ret = smb_krb5_princ_component(smb_krb5_context->krb5_context,
+                                      principal, 1, &component);
+       if (ret) {
                info1->status = DRSUAPI_DS_NAME_STATUS_NOT_FOUND;
                krb5_free_principal(smb_krb5_context->krb5_context, principal);
                return WERR_OK;
        }
-       component = krb5_princ_component(smb_krb5_context->krb5_context,
-                                        principal, 0);
-       service = (const char *)component->data;
-       component = krb5_princ_component(smb_krb5_context->krb5_context,
-                                        principal, 1);
-       dns_name = (const char *)component->data;
+       dns_name = (const char *)component.data;
 
        /* MAP it */
        namestatus = LDB_lookup_spn_alias(sam_ctx, mem_ctx,
@@ -777,8 +781,7 @@ WERROR DsCrackNameOneName(struct ldb_context *sam_ctx, TALLOC_CTX *mem_ctx,
                krb5_principal principal;
                char *unparsed_name_short;
                const char *unparsed_name_short_encoded = NULL;
-               const krb5_data *component;
-               char *service;
+               bool principal_is_host = false;
 
                ret = smb_krb5_init_context(mem_ctx, 
                                            (struct loadparm_context *)ldb_get_opaque(sam_ctx, "loadparm"), 
@@ -821,20 +824,35 @@ WERROR DsCrackNameOneName(struct ldb_context *sam_ctx, TALLOC_CTX *mem_ctx,
                        return WERR_NOT_ENOUGH_MEMORY;
                }
 
-               component = krb5_princ_component(smb_krb5_context->krb5_context,
-                                                principal, 0);
-               service = (char *)component->data;
-               if ((krb5_princ_size(smb_krb5_context->krb5_context,
-                                                       principal) == 2) &&
-                       (strcasecmp(service, "host") == 0)) {
+               if ((krb5_princ_size(smb_krb5_context->krb5_context, principal) == 2)) {
+                       krb5_data component;
+
+                       ret = smb_krb5_princ_component(smb_krb5_context->krb5_context,
+                                                      principal, 0, &component);
+                       if (ret) {
+                               krb5_free_principal(smb_krb5_context->krb5_context, principal);
+                               free(unparsed_name_short);
+                               return WERR_INTERNAL_ERROR;
+                       }
+
+                       principal_is_host = strcasecmp(component.data, "host") == 0;
+               }
+
+               if (principal_is_host) {
                        /* the 'cn' attribute is just the leading part of the name */
+                       krb5_data component;
                        char *computer_name;
                        const char *computer_name_encoded = NULL;
-                       component = krb5_princ_component(
-                                               smb_krb5_context->krb5_context,
-                                               principal, 1);
-                       computer_name = talloc_strndup(mem_ctx, (char *)component->data,
-                                                       strcspn((char *)component->data, "."));
+                       ret = smb_krb5_princ_component(
+                               smb_krb5_context->krb5_context,
+                               principal, 1, &component);
+                       if (ret) {
+                               krb5_free_principal(smb_krb5_context->krb5_context, principal);
+                               free(unparsed_name_short);
+                               return WERR_INTERNAL_ERROR;
+                       }
+                       computer_name = talloc_strndup(mem_ctx, (char *)component.data,
+                                                       strcspn((char *)component.data, "."));
                        if (computer_name == NULL) {
                                krb5_free_principal(smb_krb5_context->krb5_context, principal);
                                free(unparsed_name_short);