source: libabac/abac_pl_yy.c @ 2e9455f

/**
** abac_pl_yy.c 
**/

/* C declarations */
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>

#include "abac_stack.h"

#include "abac_pl_yy.h"
#include "abac_util.h"
#include "abac_pl_gen.h"
#include "abac_list.h"
#include "abac_term.h"
#include "abac_aspect.h"

static int debug=0;

abac_context_t *abac_context=NULL; /* context used for this parsing */
static int yy_using_this=0;
int abac_yy_error_code=0; /* keeping last error code */
int abac_rule_is_oset=0;

abac_aspect_t *abac_rule_head_aspect=NULL;
abac_aspect_t *abac_rule_tail_aspect=NULL;

/* structure to hold the range information
   within a static constraints on few types of
   oset types 
   [a..b], [a..], [..b], [a],[a,b],[many a] 
   e_yy_RANGE_MIN=1;
   e_yy_RANGE_MAX=2;
   e_yy_RANGE_TARGET=3;
*/
typedef struct _abac_yy_range_t {
    int type;
    char *val;
} abac_yy_range_t;

/* local principal structure  [keyid:USC] */
struct _abac_yy_principal_t {
    int type;
    char *sha; // sha is null when this is of object type
    char *cn; 
};

/* [principal:?Z]:..., must match a principal name */
struct _abac_yy_term_principal_t {
    int type; /* this needs to be implicitly determined */
    int is_anonymous;
    char *name;
    int isrange;
    char *cond_str;  // range string ???  not sure if this is possible
    void *cond_ptr; // ptr to a saved abac_aspect_t or a list(item_t)
    abac_yy_expression_t *cond_head_expr;
};

/* integer,float,time,urn,string types,
   if has condition, then it is a variable,
   ie,
    [int:?Year]:<1930..1932>,
   if no condition, then it is a constant, 
    ie,
    [int:10]
*/
struct _abac_yy_term_data_t {
    int is_variable;
    int is_anonymous;
    int type;
    char *name;
    char *cond_str; // range string
    void *cond_ptr; // ptr to a saved abac_aspect_t 
    abac_list_t *cond_range;
    abac_yy_expression_t *cond_head_expr; // parking stub
};

/* local term structure, will distinguish it in the future */
/* e_yy_DTERM_DATA,      all other types
   e_yy_DTERM_NAMED,     keyid:bob
   e_yy_DTERM_PRINCIPAL, principal:?P
   e_yy_DTERM_THIS,      ?this 
   e_yy_DTERM_ANONYMOUS  ? */
struct _abac_yy_term_t {
    union {
         abac_yy_principal_t *n_ptr;
         abac_yy_term_principal_t *p_ptr;
         abac_yy_term_data_t *d_ptr;
    } term;
    int type;
    struct _abac_yy_term_t *next;
    int bcnt; /* this is to track number of terms in this linked up list */
};

/* local role/oset structure, 
   e_yy_NULL_TYPE, e_yy_ROLE_TYPE, e_yy_OSET_TYPE 
*/
struct _abac_yy_roleoset_t {
   int type;
   char *name;
   abac_yy_term_t *terms;
   struct _abac_yy_roleoset_t *next;
   int bcnt; /* this is to track number of roles in this linked up list */
};


/* A, A.r, A.r.r */
/* type: e_yy_EXPR_NAMED,e_yy_EXPR_ROLE,e_yy_EXPR_LINKED */
/* A/obj, A.o, A.r.o */
/* type: e_yy_EXPR_NAMED, e_yy_EXPR_OBJECT, e_yy_EXPR_OSET,e_yy_EXPR_LINKED */
struct _abac_yy_expression_t {
   int type;
   union {
       abac_yy_principal_t *principal;
       abac_yy_term_data_t *object;
   };
   abac_yy_roleoset_t *linked_role;
   abac_yy_roleoset_t *roleoset;
   
   struct _abac_yy_expression_t *next;
   int bcnt;
};

/* local */
static void _free_yy_expression(abac_yy_expression_t *);
abac_aspect_t *validate_head(int yytype, abac_yy_expression_t *expr);
abac_aspect_t *validate_linked_tail(int yytype, abac_yy_expression_t *expr);

/************************************************************************/
void abac_yy_set_error_code(int v)
{
     abac_yy_error_code=v;
}

int abac_yy_get_rule_is_oset()
{
   return abac_rule_is_oset;
}

abac_aspect_t *abac_yy_get_rule_head_aspect()
{
    return abac_rule_head_aspect;
}

abac_aspect_t *abac_yy_get_rule_tail_aspect()
{
    return abac_rule_tail_aspect;
}

/************************************************************************/
static void _free_yy_cond_range(abac_list_t *ptr) 
{
    if (ptr != NULL) {
        abac_yy_range_t *cur;
        abac_list_foreach(ptr, cur,
            if(cur && cur->val) free(cur->val);
            free(cur);
        );
        abac_list_free(ptr);
    }
}

static char *_string_yy_cond_range(abac_list_t *ptr)
{
    assert(ptr);
    char *tmp=NULL;
    char *min=NULL;
    char *max=NULL;
    char *val=NULL;
    int type;

    abac_yy_range_t *cur;
    abac_list_foreach(ptr, cur,
        type=cur->type;
        switch (type) {
            case e_yy_RANGE_MIN:
                min=abac_xstrdup(cur->val);
                break;
            case e_yy_RANGE_MAX:
                max=abac_xstrdup(cur->val);
                break;
            case e_yy_RANGE_TARGET:
                if(val)
                    asprintf(&val,"%s,%s",val,cur->val);
                else val=abac_xstrdup(cur->val);
                break;
        }
    );
    if(max && min) {
         asprintf(&tmp,"[%s..%s]",min,max);
         free(max);
         free(min);
         return tmp;
    }
    if(max) {
         asprintf(&tmp,"[..%s]",max);
         free(max);
         return tmp;
    }
    if(min) {
         asprintf(&tmp,"[%s..]",min);
         free(min);
         return tmp;
    }
    if(val) {
         asprintf(&tmp,"[%s]",val);
         free(val);
         return tmp;
    }
    return NULL;
}

abac_list_t *add_yy_val_range(abac_list_t *ptr, char * val)
{
    abac_yy_range_t *range= 
         (abac_yy_range_t *) abac_xmalloc(sizeof(abac_yy_range_t));
    range->type=e_yy_RANGE_TARGET;
    range->val=abac_xstrdup(val);
    abac_list_add(ptr, range);
    return ptr;
}

static abac_list_t *_add_yy_range(abac_list_t *ptr, int type, char * val)
{
    abac_yy_range_t *range= 
         (abac_yy_range_t *) abac_xmalloc(sizeof(abac_yy_range_t));
    range->type=type;
    range->val=abac_xstrdup(val);
    abac_list_add(ptr, range);
    return ptr;
}

abac_list_t *make_yy_val_range(char *val)
{
    abac_list_t *ptr=abac_list_new();
    add_yy_val_range(ptr,val);
    return ptr;
}

abac_list_t *make_yy_minmax_range(char *min, char *max)
{
    abac_list_t *ptr=abac_list_new();
    _add_yy_range(ptr, e_yy_RANGE_MIN, min);
    _add_yy_range(ptr, e_yy_RANGE_MAX, max);
    return ptr;
}

abac_list_t *make_yy_min_range(char *min)
{
    abac_list_t *ptr=abac_list_new();
    _add_yy_range(ptr, e_yy_RANGE_MIN, min);
    return ptr;
}

abac_list_t *make_yy_max_range(char *max)
{
    abac_list_t *ptr=abac_list_new();
    _add_yy_range(ptr, e_yy_RANGE_MAX, max);
    return ptr;
}

/***********************************************************************/
abac_yy_term_data_t *make_yy_term_data()
{
    abac_yy_term_data_t *ptr=
              (abac_yy_term_data_t*)abac_xmalloc(sizeof(abac_yy_term_data_t));
    ptr->name=NULL;
    ptr->type=0;
    ptr->is_variable=0;
    ptr->is_anonymous=0;
    ptr->cond_str=NULL;
    ptr->cond_head_expr=NULL;
    ptr->cond_ptr=NULL;
    ptr->cond_range=NULL;
    return ptr;
}

void set_yy_term_data_name(abac_yy_term_data_t *ptr, char *name)
{
    ptr->name=abac_xstrdup(name);
}

abac_list_t *get_yy_term_data_cond_range(abac_yy_term_data_t *ptr)
{
    return ptr->cond_range;
}

char *get_yy_term_data_name(abac_yy_term_data_t *ptr)
{
    return ptr->name;
}

int is_yy_term_data_has_constraint(abac_yy_term_data_t *ptr)
{
    if(ptr->cond_head_expr != NULL)
        return 1;
    if(ptr->cond_range != NULL)
        return 1;
    return 0;
}

void set_yy_term_data_cond_range(abac_yy_term_data_t *ptr,
abac_list_t *range)
{
    ptr->cond_range=range;
}

void set_yy_term_data_cond_head_expr(abac_yy_term_data_t *ptr,
abac_yy_expression_t *expr)
{
    ptr->cond_head_expr=expr;
}

abac_yy_expression_t *get_yy_term_data_cond_head_expr(abac_yy_term_data_t *ptr)
{
    return ptr->cond_head_expr;
}

void set_yy_term_data_type(abac_yy_term_data_t *ptr, char* typestr)
{
    int type=abac_verify_term_type(typestr);
    ptr->type=type;
}

void set_yy_term_data_is_anonymous(abac_yy_term_data_t *ptr)
{
    ptr->is_anonymous=1;
}

int is_yy_term_data_type_numeric(abac_yy_term_data_t *ptr)
{
    if(ptr->type==abac_verify_term_type("integer") ||
          ptr->type==abac_verify_term_type("float"))
        return 1;
    return 0;
}

int is_yy_term_data_type_time(abac_yy_term_data_t *ptr)
{
    if(ptr->type==abac_verify_term_type("time"))
        return 1;
    return 0;
}

int is_yy_term_data_type_alpha(abac_yy_term_data_t *ptr)
{
    if(ptr->type==abac_verify_term_type("string") ||
        ptr->type==abac_verify_term_type("urn") ||
         ptr->type==abac_verify_term_type("boolean"))
        return 1;
    return 0;
}

void set_yy_term_data_cond_ptr(abac_yy_term_data_t *ptr, void *vptr)
{
    ptr->cond_ptr=vptr;
}

void set_yy_term_data_cond_str(abac_yy_term_data_t *ptr, char *cond)
{
    ptr->cond_str=abac_xstrdup(cond);
}

void set_yy_term_data_is_variable(abac_yy_term_data_t *ptr)
{
    ptr->is_variable=1;
}

int get_yy_term_data_is_variable(abac_yy_term_data_t *ptr)
{
    return ptr->is_variable;
}

static void _free_yy_term_data(abac_yy_term_data_t *ptr)
{
    free(ptr->name);
    if(ptr->cond_str)
        free(ptr->cond_str);
    if(ptr->cond_head_expr)
        _free_yy_expression(ptr->cond_head_expr);
    if(ptr->cond_range);
        _free_yy_cond_range(ptr->cond_range);
    free(ptr);
}

abac_yy_term_principal_t *make_yy_term_principal()
{
    abac_yy_term_principal_t *ptr=
            (abac_yy_term_principal_t*)abac_xmalloc(sizeof(abac_yy_term_principal_t));
    ptr->type=0;/* this is not known */
    ptr->is_anonymous=0;
    ptr->name=NULL;
    ptr->isrange=0;
    ptr->cond_str=NULL;
    ptr->cond_ptr=NULL;
    ptr->cond_head_expr=NULL;
    return ptr;
}

static void _set_using_this()
{
    yy_using_this=1;
}

int abac_yy_get_using_this()
{
    return yy_using_this;
}

void set_yy_term_principal_isrange(abac_yy_term_principal_t *ptr, int isrange)
{
    ptr->isrange=isrange;
}

void set_yy_term_principal_name(abac_yy_term_principal_t *ptr, char *name)
{
    ptr->name=abac_xstrdup(name);
}

void set_yy_term_principal_cond_ptr(abac_yy_term_principal_t *ptr, void *vptr)
{
    ptr->cond_ptr=vptr;
}

void set_yy_term_principal_cond_str(abac_yy_term_principal_t *ptr, char *cond)
{
    ptr->cond_str=abac_xstrdup(cond);
}

void set_yy_term_principal_is_anonymous(abac_yy_term_principal_t *ptr)
{
    ptr->is_anonymous=1;
}

abac_yy_expression_t *get_yy_term_principal_cond_head_expr(abac_yy_term_principal_t *ptr)
{
    return ptr->cond_head_expr;
}

void set_yy_term_principal_cond_head_expr(abac_yy_term_principal_t *ptr, 
abac_yy_expression_t *expr)
{
    ptr->cond_head_expr=expr;
}

static void _free_yy_term_principal(abac_yy_term_principal_t *ptr)
{
    free(ptr->name);
    if(ptr->cond_str)
        free(ptr->cond_str);
    if(ptr->cond_head_expr)
        _free_yy_expression(ptr->cond_head_expr);
    free(ptr);
}

abac_yy_term_t *make_yy_term_dterm_this()
{
    abac_yy_term_t *ptr=(abac_yy_term_t*)abac_xmalloc(sizeof(abac_yy_term_t));
    ptr->type = e_yy_DTERM_THIS;
    ptr->next=NULL;
    ptr->bcnt=1;
    _set_using_this();
    return ptr;
}

abac_yy_term_t *make_yy_term_dterm_anonymous()
{
    abac_yy_term_t *ptr=(abac_yy_term_t*)abac_xmalloc(sizeof(abac_yy_term_t));
    ptr->type = e_yy_DTERM_ANONYMOUS;
    ptr->next=NULL;
    ptr->bcnt=1;
    return ptr;
}

abac_yy_term_t *make_yy_term_dterm_principal(abac_yy_term_principal_t *pptr)
{
    abac_yy_term_t *ptr=(abac_yy_term_t*)abac_xmalloc(sizeof(abac_yy_term_t));
    if(pptr->is_anonymous) 
        ptr->type = e_yy_DTERM_ANONYMOUS;
        else ptr->type = e_yy_DTERM_PRINCIPAL;
    ptr->term.p_ptr=pptr;
    ptr->next=NULL;
    ptr->bcnt=1;
    return ptr;
}

abac_yy_term_t *make_yy_term_dterm_named(abac_yy_principal_t *nptr)
{
    abac_yy_term_t *ptr=(abac_yy_term_t*)abac_xmalloc(sizeof(abac_yy_term_t));
    ptr->type = e_yy_DTERM_NAMED;
    ptr->term.n_ptr=nptr;
    ptr->next=NULL;
    ptr->bcnt=1;
    return ptr;
}

abac_yy_term_t *make_yy_term_dterm_data(abac_yy_term_data_t *dptr)
{
    abac_yy_term_t *ptr=(abac_yy_term_t*)abac_xmalloc(sizeof(abac_yy_term_t));

    if(dptr->is_anonymous)
        ptr->type = e_yy_DTERM_ANONYMOUS;
        else ptr->type = e_yy_DTERM_DATA;
    ptr->term.d_ptr=dptr;
    ptr->next=NULL;
    ptr->bcnt=1;
    return ptr;
}

/****************************************************************************/
abac_yy_principal_t *make_yy_principal(char *sha, char *cn, int type)
{
    abac_yy_principal_t *ptr=
               (abac_yy_principal_t*)abac_xmalloc(sizeof(abac_yy_principal_t));
    /* add p to yyparse's principal */
    if(sha) ptr->sha=abac_xstrdup(sha);
        else ptr->sha=NULL;
    if(cn) ptr->cn=abac_xstrdup(cn);
        else ptr->cn=NULL;
    ptr->type=type;
    return ptr;
}

static void _free_yy_principal(abac_yy_principal_t *ptr)
{
    if(ptr->sha) free(ptr->sha);
    if(ptr->cn) free(ptr->cn);
    free(ptr);
}

int get_yy_principal_type(abac_yy_principal_t *ptr)
{
    return ptr->type;
}

char *get_yy_principal_name(abac_yy_principal_t *ptr)
{
    if(USE("ABAC_CN") && ptr->cn)
       return ptr->cn;
    return ptr->sha;
}

char *get_yy_principal_cn(abac_yy_principal_t *ptr)
{
        return ptr->cn;
}

char *get_yy_principal_sha(abac_yy_principal_t *ptr)
{
        return ptr->sha;
}

/*************************************************************************/

abac_yy_term_t *add_yy_term(abac_yy_term_t *nterm, abac_yy_term_t *terms)
{
    int i=terms->bcnt;
    nterm->next=terms;
    nterm->bcnt=i+1;
    return nterm;
}

static void _free_yy_term(abac_yy_term_t *ptr)
{
    switch (ptr->type) {
        case e_yy_DTERM_DATA:
            _free_yy_term_data(ptr->term.d_ptr);
            break;
        case e_yy_DTERM_NAMED:
            _free_yy_principal(ptr->term.n_ptr);
            break;
        case e_yy_DTERM_PRINCIPAL:
            _free_yy_term_principal(ptr->term.p_ptr);
            break;
        case e_yy_DTERM_ANONYMOUS:
        case e_yy_DTERM_THIS:
            break;
    }
    if(ptr->next)
        _free_yy_term(ptr->next);
    free(ptr);
}

/*************************************************************************/
abac_yy_roleoset_t *make_yy_roleoset_role(char *name, abac_yy_term_t *terms)
{
    abac_yy_roleoset_t *ptr=
         (abac_yy_roleoset_t*)abac_xmalloc(sizeof(abac_yy_roleoset_t));
    ptr->name=abac_xstrdup(name);
    ptr->terms=terms;
    ptr->next=NULL;
    ptr->bcnt=1;
    ptr->type=e_yy_ROLE_TYPE;
    return ptr;
}

static void _free_yy_roleoset(abac_yy_roleoset_t *ptr)
{
    free(ptr->name);
    if(ptr->terms)
        _free_yy_term(ptr->terms);
    if(ptr->next)
        _free_yy_roleoset(ptr->next);
    free(ptr);
}

/***************************************************************************/
abac_yy_roleoset_t *make_yy_roleoset_oset(char *name, abac_yy_term_t *terms)
{
    abac_yy_roleoset_t *ptr=
           (abac_yy_roleoset_t*)abac_xmalloc(sizeof(abac_yy_roleoset_t));
    ptr->name=abac_xstrdup(name);
    ptr->terms=terms;
    ptr->next=NULL;
    ptr->bcnt=1;
    ptr->type=e_yy_OSET_TYPE;
    return ptr;
}

/***************************************************************************/

/* type: e_yy_EXPR_NAMED, e_yy_EXPR_OBJECT, e_yy_EXPR_OSET,e_yy_EXPR_LINKED */

abac_yy_expression_t *make_yy_expression(int type,void *pptr, 
abac_yy_roleoset_t *optr, abac_yy_roleoset_t *linked_role)
{
    abac_yy_expression_t *ptr=
         (abac_yy_expression_t*)abac_xmalloc(sizeof(abac_yy_expression_t));
    ptr->type = type;
    if(type == e_yy_EXPR_OBJECT) {
        ptr->object=(abac_yy_term_data_t *)pptr;
        } else {
            ptr->principal = (abac_yy_principal_t *)pptr;
    }
    ptr->roleoset = optr;
    ptr->linked_role=linked_role;
    ptr->next=NULL;

    return ptr;
}

abac_yy_term_data_t *get_yy_expression_object(abac_yy_expression_t *ptr)
{
   if(ptr->type == e_yy_EXPR_OBJECT)
       return ptr->object;
   return NULL;
}

abac_yy_expression_t *add_yy_expression(abac_yy_expression_t *nexpr,
                                             abac_yy_expression_t *exprs)
{
    int i=exprs->bcnt;
    nexpr->next=exprs;
    nexpr->bcnt=i+1;
    return nexpr;
}

static void _free_yy_expression(abac_yy_expression_t *ptr)
{
    if(ptr->type == e_yy_EXPR_OBJECT) {
       if(ptr->object)
           _free_yy_term_data(ptr->object);
       } else {
           if(ptr->principal)
               _free_yy_principal(ptr->principal);
    }
    if(ptr->roleoset) _free_yy_roleoset(ptr->roleoset);
    if(ptr->linked_role)
        _free_yy_roleoset(ptr->linked_role);
    if(ptr->next)
        _free_yy_expression(ptr->next);

    free(ptr);
}

/***************************************************************************/
/* add the oset condition to constraint list */
void make_yy_oset_constraint(abac_yy_term_data_t *ptr, char *tail_string)
{
   abac_yy_expression_t *cond_expr=get_yy_term_data_cond_head_expr(ptr);
   if(cond_expr) {
       abac_aspect_t *cond_aspect=NULL;
       if(cond_expr->type == e_yy_EXPR_LINKED)
           cond_aspect=validate_linked_tail(e_yy_OSET_TYPE,cond_expr);
       else cond_aspect=validate_head(e_yy_OSET_TYPE,cond_expr);
       if(cond_aspect != NULL) {
           if(debug) fprintf(stderr,"make_yy_oset_constraint..\n");
           set_yy_term_data_cond_ptr(ptr,cond_aspect);
       }
   }
} 

/* add the role condition to constraint list */
void make_yy_role_constraint(abac_yy_term_principal_t *ptr, char *tail_string)
{
   abac_yy_expression_t *cond_expr=get_yy_term_principal_cond_head_expr(ptr);
   if(cond_expr) {
       abac_aspect_t *cond_aspect=NULL;
       if(cond_expr->type == e_yy_EXPR_LINKED)
           cond_aspect=validate_linked_tail(e_yy_ROLE_TYPE,cond_expr);
       else cond_aspect=validate_head(e_yy_ROLE_TYPE,cond_expr);
       if(cond_aspect != NULL) {
          if(debug) fprintf(stderr,"make_yy_role_constraint..\n");
          set_yy_term_principal_cond_ptr(ptr,cond_aspect);
          set_yy_term_principal_isrange(ptr,0);
       }
   }
}


/****************************************************************/
static void _aspect_add_terms(int linked, abac_aspect_t *aspect_ptr, 
abac_yy_term_t *terms)
{
    abac_yy_term_t *curr = terms;
    int type;
    int isnamed;
    int isrange;
    char *name;
    char *cond;
    void *ptr;

    while (curr) {
        name=NULL;
        cond=NULL;
        ptr=NULL;
        isnamed=0; 
        isrange=0;
        switch (curr->type) {
           case e_yy_DTERM_DATA:
           {
               abac_yy_term_data_t *dptr=curr->term.d_ptr;
               type=dptr->type;
               name=abac_xstrdup(dptr->name);
               if(dptr->cond_str)
                  cond=abac_xstrdup(dptr->cond_str);
               ptr=dptr->cond_ptr;
               isrange=(dptr->cond_range!=NULL)?1:0;
               break;
           }
           case e_yy_DTERM_PRINCIPAL:
           {
               abac_yy_term_principal_t *pptr=curr->term.p_ptr;
               type=abac_verify_term_type("principal");
               name=abac_xstrdup(pptr->name);
               if(pptr->cond_str)
                  cond=abac_xstrdup(pptr->cond_str);
               ptr=pptr->cond_ptr;
               isrange=pptr->isrange;
               break;
           }
           case e_yy_DTERM_NAMED:
           {
              abac_yy_principal_t *pptr=curr->term.n_ptr;
              type=pptr->type;
              name=abac_xstrdup(get_yy_principal_name(pptr));
              isnamed=1; 
              break;
           }
           case e_yy_DTERM_ANONYMOUS:
           {
              type=abac_verify_term_type("anonymous");
              name=abac_xstrdup("_");
              break;
           }
           case e_yy_DTERM_THIS:
           {
              type=abac_verify_term_type("this");
              name=abac_xstrdup("This");
              break;
           }
       }
       abac_term_t *param=NULL;
       if(isnamed)
           param=abac_term_named_new(type,name);
           else param=abac_term_new(type,name,isrange,cond,ptr);
       if (linked) 
           abac_aspect_add_linked_param(aspect_ptr, param);
           else
                abac_aspect_add_param(aspect_ptr, param);
       curr=curr->next;
   }
}

static void _aspect_add_linked_terms(abac_aspect_t *ptr, abac_yy_term_t *terms)
{
    int linked=1;
    _aspect_add_terms(linked, ptr, terms);
}

static void _aspect_add_aspect_terms(abac_aspect_t *ptr, abac_yy_term_t *terms)
{
    int linked=0;
    _aspect_add_terms(linked, ptr, terms);
}

abac_aspect_t *validate_intersected_tail(abac_aspect_t *ptr)
{
    abac_aspect_t *ret_ptr=abac_aspect_intersection_new(ptr);
    return ret_ptr;
}

/* A.oset, A.role */
abac_aspect_t *validate_head(int yytype, abac_yy_expression_t *expr)
{
     abac_yy_principal_t *principal=expr->principal;
     abac_yy_roleoset_t *ptr=expr->roleoset;
    
     char *principalname=get_yy_principal_sha(principal);
     char *name=ptr->name;
     abac_yy_term_t *terms=ptr->terms;

     abac_aspect_t *aptr=NULL;
     if(yytype==e_yy_OSET_TYPE)
         aptr=abac_aspect_oset_new(principalname, name);
         else aptr=abac_aspect_role_new(principalname, name);

     if (aptr==NULL) {
         abac_yy_set_error_code(ABAC_YY_INVALID_HEAD);
         goto error;
     }

     // insert the params for the oset
     if(terms) {
          _aspect_add_aspect_terms(aptr, terms);
     }
     return aptr;

error:
     return NULL;
}

abac_aspect_t *validate_head_oset(abac_yy_expression_t *expr)
{
     return validate_head(e_yy_OSET_TYPE,expr);
}

abac_aspect_t *validate_head_role(abac_yy_expression_t *expr)
{
     return validate_head(e_yy_ROLE_TYPE,expr);
}

/*****************************************************************************/
/* B */
abac_aspect_t *validate_named_tail(int yytype, abac_yy_expression_t *expr)
{
     abac_yy_principal_t *principal=expr->principal;
     char *principalname=get_yy_principal_sha(principal);

     abac_aspect_t *ptr=NULL;
     if(yytype==e_yy_OSET_TYPE)
         ptr=abac_aspect_oset_principal_new(principalname);
         else ptr=abac_aspect_role_principal_new(principalname);
     if (ptr==NULL)
         goto error;
     return ptr;

error:
     panic("can not generate a simple named tail oset aspect");
     return NULL;
}


/* [keyid:alpha].oset:documents([string:'proj1'])<-[urn:'file//fileA'] */
abac_aspect_t *validate_object_tail(int yytype,abac_yy_expression_t *expr)
{
     abac_yy_term_data_t *object=get_yy_expression_object(expr);
     assert(object != NULL);

     char *name=object->name;
     int type=object->type;
     char *cond=object->cond_str;
     void *ptr=object->cond_ptr;
     int isrange=(object->cond_range!=NULL)?1:0;
     abac_term_t *term=abac_term_new(type,name,isrange,cond,ptr);
     abac_aspect_t *aptr=NULL;
     if(yytype==e_yy_OSET_TYPE)
         aptr=abac_aspect_oset_object_new(term);
         else
             goto error; /* can not be a role expression with obj */
     if (aptr==NULL)
         goto error;
     return aptr;

error:
     panic("can not generate a simple object tail oset aspect");
     return NULL;
}


/* B.role or B.oset */
abac_aspect_t *validate_some_tail(int yytype, abac_yy_expression_t *expr)
{
     abac_yy_principal_t *principal=expr->principal;
     abac_yy_roleoset_t *eptr=expr->roleoset;

     char *principalname=get_yy_principal_sha(principal);
     char *name=eptr->name;
     abac_yy_term_t *terms=eptr->terms;

     abac_aspect_t *ptr=NULL;
     if(yytype==e_yy_OSET_TYPE)
         ptr=abac_aspect_oset_new(principalname, name);
         else
             ptr=abac_aspect_role_new(principalname, name);
     if (ptr==NULL)
         goto error;

     if(terms) {
         _aspect_add_aspect_terms(ptr, terms);
     }
     return ptr;

error:
     panic("can not generate a simple tail aspect");
     return NULL;
}

/* B.role.role or B.role.oset */
abac_aspect_t *validate_linked_tail(int yytype, abac_yy_expression_t *expr)
{
     abac_yy_principal_t *principal=expr->principal;

     abac_yy_roleoset_t *eptr=expr->roleoset;
     abac_yy_roleoset_t *linked_role=expr->linked_role;

     char *principalname=get_yy_principal_sha(principal);
     char *name=eptr->name;
     abac_yy_term_t *terms=eptr->terms;

     char *linkedrolename=linked_role->name;
     abac_yy_term_t *linked_terms=linked_role->terms;

     abac_aspect_t *ptr=NULL;
     if(yytype==e_yy_OSET_TYPE)
         ptr=abac_aspect_oset_linking_new(principalname,
                                            linkedrolename, name);
         else ptr=abac_aspect_role_linking_new(principalname,
                                            linkedrolename, name);
     if (ptr==NULL)
         goto error;

     if(linked_terms) {
         _aspect_add_linked_terms(ptr, linked_terms);
     }
     if(terms) {
         _aspect_add_aspect_terms(ptr, terms);
     }

     return ptr;

error:
     panic("can not generate linked tail oset");
     return NULL;
}


/**********************************************************************/
int make_oset_statement(abac_yy_expression_t *headexpr, abac_yy_expression_t *tailexpr) 
{ 
    int rc=0;
    abac_aspect_t *head_oset=NULL;
    abac_aspect_t *tail_oset=NULL;

/* build up left side's abac oset structure */
    head_oset=validate_head(e_yy_OSET_TYPE, headexpr);
    if(head_oset == NULL) {
        rc=1;
        goto error;
    }

/* build up the right side's abac oset structure */
    abac_yy_expression_t *curr_tail = tailexpr;
    int intersecting=(tailexpr->next != NULL)? 1:0;
    abac_aspect_t *curr_oset = NULL;
        while (curr_tail) {
            switch(curr_tail->type) {
                case e_yy_EXPR_OBJECT:
                    curr_oset=validate_object_tail(e_yy_OSET_TYPE,curr_tail);
                    break;
                case e_yy_EXPR_NAMED:
                    curr_oset=validate_named_tail(e_yy_OSET_TYPE,curr_tail);
                    break;
                case e_yy_EXPR_OSET:
                    curr_oset=validate_some_tail(e_yy_OSET_TYPE,curr_tail);
                    break;
                case e_yy_EXPR_LINKED:
                    curr_oset=validate_linked_tail(e_yy_OSET_TYPE,curr_tail);
                    break;
            }
            if(curr_oset==NULL) {
                rc=1;
                goto error;
            }

            /* check if first one */
            if(tail_oset==NULL) {
                if(intersecting) 
                    tail_oset=validate_intersected_tail(curr_oset);
                    else 
                        tail_oset=curr_oset;
                } else {  
                    abac_aspect_add_intersecting_aspect(tail_oset,curr_oset);
            }
            curr_tail=curr_tail->next;
        } /* while */

        if(debug) {
            fprintf(stderr,"aspect head_oset: ");
            abac_print_aspect_string_with_condition(head_oset,stderr);
            fprintf(stderr,"\n");
            fprintf(stderr,"aspect tail_oset: ");
            abac_print_aspect_string_with_condition(tail_oset,stderr);
            fprintf(stderr,"\n");
        }

error:
        _free_yy_expression(headexpr);
        _free_yy_expression(tailexpr);
        abac_rule_head_aspect=head_oset;
        abac_rule_tail_aspect=tail_oset;
        abac_rule_is_oset=1;
    return rc;
}

/*****************************************************************************/
abac_list_t *validate_range(abac_list_t *ptr)
{
    abac_list_t *nlist=abac_list_new();

    abac_item_t *nitem;
    abac_yy_range_t *cur;
    char *val;
    int type;
    abac_list_foreach(ptr, cur,
        if(cur) {
            type=cur->type;
            val=cur->val;
            if(type==e_yy_RANGE_MIN) nitem=abac_item_new(abac_min_item_type(),val);
            if(type==e_yy_RANGE_MAX) nitem=abac_item_new(abac_max_item_type(),val);
            if(type==e_yy_RANGE_TARGET) nitem=abac_item_new(abac_target_item_type(),val);
            abac_list_add(nlist,nitem);
        }
    );
    return nlist;
}

/****************************************************************/
void make_yy_range_constraint(abac_yy_term_data_t *ptr)
{
    if(is_yy_term_data_type_numeric(ptr) ||
        is_yy_term_data_type_alpha(ptr) ||
           is_yy_term_data_type_time(ptr)) {
       abac_list_t *rlist=get_yy_term_data_cond_range(ptr);
       if(rlist) {
           abac_list_t *nlist=validate_range(rlist);
           set_yy_term_data_cond_ptr(ptr,nlist);
       }
    }
}
/*****************************************************************************/
abac_context_t *get_abac_context()
{
    assert(abac_context);
    return abac_context;
}

/* build up the abac structure */
int make_role_statement(abac_yy_expression_t *headexpr, abac_yy_expression_t *tailexpr) 
{ 
    int rc=0;
    abac_aspect_t *head_role=NULL;
    abac_aspect_t *tail_role=NULL;

/* build up left side's abac role structure */
    head_role=validate_head(e_yy_ROLE_TYPE,headexpr);
    if(head_role == NULL) {
        rc=1;
        goto error;
    }

/* build up the right side's abac role structure */
    abac_yy_expression_t *curr_tail = tailexpr;
    int intersecting=(tailexpr->next != NULL)? 1:0;
    abac_aspect_t *curr_role = NULL;
        while (curr_tail) {
            switch(curr_tail->type) {
                case e_yy_EXPR_NAMED:
                    curr_role=validate_named_tail(e_yy_ROLE_TYPE,curr_tail);
                    break;
                case e_yy_EXPR_ROLE:
                    curr_role=validate_some_tail(e_yy_ROLE_TYPE,curr_tail);
                    break;
                case e_yy_EXPR_LINKED:
                    curr_role=validate_linked_tail(e_yy_ROLE_TYPE,curr_tail);
                    break;
            }
            if(curr_role==NULL) {
                rc=1;
                goto error;
            }

            /* check if first one */
            if(tail_role==NULL) {
                if(intersecting) 
                    tail_role=validate_intersected_tail(curr_role);
                    else 
                        tail_role=curr_role;
                } else {  
                    abac_aspect_add_intersecting_aspect(tail_role,curr_role);
            }
            curr_tail=curr_tail->next;
        } /* while */

        if(debug) {
            fprintf(stderr,"aspect head_role: ");
            abac_print_aspect_string_with_condition(head_role,stderr);
            fprintf(stderr,"\n");
            fprintf(stderr,"aspect tail_role: ");
            abac_print_aspect_string_with_condition(tail_role,stderr);
            fprintf(stderr,"\n");
        }

error:
        _free_yy_expression(headexpr);
        _free_yy_expression(tailexpr);
        abac_rule_head_aspect=head_role;
        abac_rule_tail_aspect=tail_role;
        abac_rule_is_oset=0;

        return rc;
}

/************************************************************************/
void abac_yy_init(abac_context_t *ctxt)
{
   yy_using_this=0;
   abac_context=ctxt;
   abac_yyinit();
}

/************************************************************************/
/* this is called to parse a string into 2 aspect structures            */
/* NEED TO BE LOCKED HERE XXX */
int abac_yy_parse(abac_context_t *ctxt, char* attr_string, abac_aspect_t **head_aspect, abac_aspect_t **tail_aspect, int *using_this)
{
    /*ctxt could be null*/
    abac_ll_reset_yyfptr(attr_string);
    abac_yy_init(ctxt);
    int rc=yyparse();
    if (rc) {
        free(attr_string);
        abac_yy_set_error_code(ABAC_RT_CERT_INVALID);
        return 1;
    }
    *head_aspect = abac_yy_get_rule_head_aspect();
    *tail_aspect = abac_yy_get_rule_tail_aspect();
    *using_this= abac_yy_get_using_this();
    return 0;
}