Added new hostswithgroup policy function

Changelog: Added new hostswithgroup function to get hosts from a group, selecting a specific field. This function is enterprise only.
Ticket: ENT-11325
Signed-off-by: Victor Moene <victor.moene@northern.tech>

Author: victormlg

examples/hostswithgroup.cf

@@ -0,0 +1,20 @@
+body common control
+{
+      bundlesequence => { "example" };
+      inputs => { "$(sys.libdir)/stdlib.cf" };
+}
+
+
+bundle agent example
+{
+  vars:
+
+    am_policy_hub::
+      "host_list" slist => hostswithgroup( "Linux", "name" );
+
+  files:
+    am_policy_hub::
+      "/tmp/master_config.cfg"
+      edit_line => insert_lines("host=$(host_list)"),
+      create => "true";
+}

libpromises/cf3.defs.h

@@ -722,6 +722,11 @@ enum cfopaction
     cfa_warn,
 };
 
+enum hostswithfieldenum {
+    HOSTS_WITH_CLASS,
+    HOSTS_WITH_GROUP
+};
+
 typedef enum
 {
     BACKUP_OPTION_BACKUP,

libpromises/enterprise_stubs.c

@@ -175,12 +175,11 @@ ENTERPRISE_FUNC_8ARG_DEFINE_STUB(void *, CfRegLDAP, EvalContext *, ctx, char *,
     return NULL;
 }
 
-ENTERPRISE_FUNC_4ARG_DEFINE_STUB(bool, ListHostsWithClass, EvalContext *, ctx, Rlist **, return_list, char *, class_name, char *, return_format)
+ENTERPRISE_FUNC_5ARG_DEFINE_STUB(bool, ListHostsWithField, EvalContext *, ctx, Rlist **, return_list, char *, field_value, char *, return_format, int, function_type)
 {
     Log(LOG_LEVEL_ERR, "Host class counting is only available in CFEngine Enterprise");
     return false;
 }
-
 /* cf-serverd: server_transform.c, cf-serverd.c */
 
 ENTERPRISE_FUNC_3ARG_DEFINE_STUB(bool, TranslatePath, const char *, from, char *, to, size_t, to_size)

libpromises/evalfunction.c

@@ -737,15 +737,30 @@ static FnCallResult FnCallHostsSeen(ARG_UNUSED EvalContext *ctx, ARG_UNUSED cons
 
 /*********************************************************************/
 
-static FnCallResult FnCallHostsWithClass(EvalContext *ctx, ARG_UNUSED const Policy *policy, ARG_UNUSED const FnCall *fp, const Rlist *finalargs)
+static FnCallResult FnCallHostsWithField(EvalContext *ctx, ARG_UNUSED const Policy *policy, ARG_UNUSED const FnCall *fp, const Rlist *finalargs)
 {
+    assert(fp != NULL);
     Rlist *returnlist = NULL;
 
-    char *class_name = RlistScalarValue(finalargs);
+    char *field_value = RlistScalarValue(finalargs);
     char *return_format = RlistScalarValue(finalargs->next);
-
-    if (!ListHostsWithClass(ctx, &returnlist, class_name, return_format))
+    if (StringEqual(fp->name, "hostswithclass"))
+    {
+        if (!ListHostsWithField(ctx, &returnlist, field_value, return_format, HOSTS_WITH_CLASS))
+        {
+            return FnFailure();
+        }
+    }
+    else if (StringEqual(fp->name, "hostswithgroup"))
     {
+        if (!ListHostsWithField(ctx, &returnlist, field_value, return_format, HOSTS_WITH_GROUP))
+        {
+            return FnFailure();
+        }
+    }
+    else
+    {
+        ProgrammingError("HostsWithField with unknown call function %s, aborting", fp->name);
         return FnFailure();
     }
 
@@ -9754,6 +9769,13 @@ static const FnCallArg HOSTSWITHCLASS_ARGS[] =
     {NULL, CF_DATA_TYPE_NONE, NULL}
 };
 
+static const FnCallArg HOSTSWITHGROUP_ARGS[] =
+{
+    {"[a-zA-Z0-9_]+", CF_DATA_TYPE_STRING, "Group name to look for"},
+    {"name,address,hostkey", CF_DATA_TYPE_OPTION, "Type of return value desired"},
+    {NULL, CF_DATA_TYPE_NONE, NULL}
+};
+
 static const FnCallArg IFELSE_ARGS[] =
 {
     {NULL, CF_DATA_TYPE_NONE, NULL}
@@ -10606,7 +10628,9 @@ const FnCallType CF_FNCALL_TYPES[] =
                   FNCALL_OPTION_NONE, FNCALL_CATEGORY_COMM, SYNTAX_STATUS_NORMAL),
     FnCallTypeNew("hostsseen", CF_DATA_TYPE_STRING_LIST, HOSTSSEEN_ARGS, &FnCallHostsSeen, "Extract the list of hosts last seen/not seen within the last arg1 hours",
                   FNCALL_OPTION_NONE, FNCALL_CATEGORY_COMM, SYNTAX_STATUS_NORMAL),
-    FnCallTypeNew("hostswithclass", CF_DATA_TYPE_STRING_LIST, HOSTSWITHCLASS_ARGS, &FnCallHostsWithClass, "Extract the list of hosts with the given class set from the hub database (enterprise extension)",
+    FnCallTypeNew("hostswithclass", CF_DATA_TYPE_STRING_LIST, HOSTSWITHCLASS_ARGS, &FnCallHostsWithField, "Extract the list of hosts with the given class set from the hub database (enterprise extension)",
+                  FNCALL_OPTION_NONE, FNCALL_CATEGORY_COMM, SYNTAX_STATUS_NORMAL),
+    FnCallTypeNew("hostswithgroup", CF_DATA_TYPE_STRING_LIST, HOSTSWITHGROUP_ARGS, &FnCallHostsWithField, "Extract the list of hosts of a given group from the hub database (enterprise extension)",
                   FNCALL_OPTION_NONE, FNCALL_CATEGORY_COMM, SYNTAX_STATUS_NORMAL),
     FnCallTypeNew("hubknowledge", CF_DATA_TYPE_STRING, HUB_KNOWLEDGE_ARGS, &FnCallHubKnowledge, "Read global knowledge from the hub host by id (enterprise extension)",
                   FNCALL_OPTION_CACHED, FNCALL_CATEGORY_COMM, SYNTAX_STATUS_NORMAL),

libpromises/prototypes3.h

@@ -74,7 +74,7 @@ ENTERPRISE_FUNC_8ARG_DECLARE(void *, CfRegLDAP, EvalContext *, ctx, char *, uri,
 ENTERPRISE_VOID_FUNC_3ARG_DECLARE(void, CacheUnreliableValue, char *, caller, char *, handle, char *, buffer);
 ENTERPRISE_FUNC_3ARG_DECLARE(int, RetrieveUnreliableValue, char *, caller, char *, handle, char *, buffer);
 ENTERPRISE_FUNC_3ARG_DECLARE(bool, TranslatePath, const char *, from, char *, to, size_t, to_size);
-ENTERPRISE_FUNC_4ARG_DECLARE(bool, ListHostsWithClass, EvalContext *, ctx, Rlist **, return_list, char *, class_name, char *, return_format);
+ENTERPRISE_FUNC_5ARG_DECLARE(bool, ListHostsWithField, EvalContext *, ctx, Rlist **, return_list, char *, field_value, char *, return_format, int, function_type);
 
 ENTERPRISE_VOID_FUNC_2ARG_DECLARE(void, CheckAndSetHAState, const char *, workdir, EvalContext *, ctx);
 ENTERPRISE_VOID_FUNC_0ARG_DECLARE(void, ReloadHAConfig);