/*
 * include/proto/acl.h
 * This file provides interface definitions for ACL manipulation.
 *
 * Copyright (C) 2000-2013 Willy Tarreau - w@1wt.eu
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation, version 2.1
 * exclusively.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

#ifndef _PROTO_ACL_H
#define _PROTO_ACL_H

#include <common/config.h>
#include <types/acl.h>
#include <proto/sample.h>

/*
 * FIXME: we need destructor functions too !
 */

/* Negate an acl result. This turns (ACL_PAT_FAIL, ACL_PAT_MISS, ACL_PAT_PASS)
 * into (ACL_PAT_PASS, ACL_PAT_MISS, ACL_PAT_FAIL).
 */
static inline int acl_neg(int res)
{
	return (3 >> res);
}

/* Convert an acl result to a boolean. Only ACL_PAT_PASS returns 1. */
static inline int acl_pass(int res)
{
	return (res >> 1);
}

/* Return a pointer to the ACL <name> within the list starting at <head>, or
 * NULL if not found.
 */
struct acl *find_acl_by_name(const char *name, struct list *head);

/* Return a pointer to the ACL keyword <kw> within the list starting at <head>,
 * or NULL if not found. Note that if <kw> contains an opening parenthesis,
 * only the left part of it is checked.
 */
struct acl_keyword *find_acl_kw(const char *kw);

/* Parse an ACL expression starting at <args>[0], and return it.
 * Right now, the only accepted syntax is :
 * <subject> [<value>...]
 */
struct acl_expr *parse_acl_expr(const char **args, char **err, struct arg_list *al);

/* Purge everything in the acl <acl>, then return <acl>. */
struct acl *prune_acl(struct acl *acl);

/* Parse an ACL with the name starting at <args>[0], and with a list of already
 * known ACLs in <acl>. If the ACL was not in the list, it will be added.
 * A pointer to that ACL is returned.
 *
 * args syntax: <aclname> <acl_expr>
 */
struct acl *parse_acl(const char **args, struct list *known_acl, char **err, struct arg_list *al);

/* Purge everything in the acl_cond <cond>, then return <cond>. */
struct acl_cond *prune_acl_cond(struct acl_cond *cond);

/* Parse an ACL condition starting at <args>[0], relying on a list of already
 * known ACLs passed in <known_acl>. The new condition is returned (or NULL in
 * case of low memory). Supports multiple conditions separated by "or".
 */
struct acl_cond *parse_acl_cond(const char **args, struct list *known_acl, int pol, char **err, struct arg_list *al);

/* Builds an ACL condition starting at the if/unless keyword. The complete
 * condition is returned. NULL is returned in case of error or if the first
 * word is neither "if" nor "unless". It automatically sets the file name and
 * the line number in the condition for better error reporting, and sets the
 * HTTP initialization requirements in the proxy. If <err> is not NULL, it will
 * be set to an error message upon errors, that the caller will have to free.
 */
struct acl_cond *build_acl_cond(const char *file, int line, struct proxy *px, const char **args, char **err);

/* Execute condition <cond> and return either ACL_PAT_FAIL, ACL_PAT_MISS or
 * ACL_PAT_PASS depending on the test results. This function only computes the
 * condition, it does not apply the polarity required by IF/UNLESS, it's up to
 * the caller to do this.
 */
int acl_exec_cond(struct acl_cond *cond, struct proxy *px, struct session *l4, void *l7, unsigned int opt);

/* Returns a pointer to the first ACL conflicting with usage at place <where>
 * which is one of the SMP_VAL_* bits indicating a check place, or NULL if
 * no conflict is found. Only full conflicts are detected (ACL is not usable).
 * Use the next function to check for useless keywords.
 */
const struct acl *acl_cond_conflicts(const struct acl_cond *cond, unsigned int where);

/* Returns a pointer to the first ACL and its first keyword to conflict with
 * usage at place <where> which is one of the SMP_VAL_* bits indicating a check
 * place. Returns true if a conflict is found, with <acl> and <kw> set (if non
 * null), or false if not conflict is found. The first useless keyword is
 * returned.
 */
int acl_cond_kw_conflicts(const struct acl_cond *cond, unsigned int where, struct acl const **acl, char const **kw);

/* parse the <text> with <expr> compliant parser. <pattern> is a context for
 * the current parsed acl. It must initialized at NULL:
 *
 *    struct acl_pattern *pattern = NULL
 *    acl_register_pattern(..., &pattern, ...);
 *
 * patflag are a combination of 'ACL_PAT_F_*' flags pattern compatible. see
 * <types/acl.h>.
 *
 * The function returns 1 if the processing is ok, return -1 if the parser
 * fails, with <err> message filled. It returns -2 in "out of memory"
 * error case.
 */
int acl_register_pattern(struct acl_expr *expr, char *text, struct acl_pattern **pattern, int patflags, char **err);

/*
 * Find targets for userlist and groups in acl. Function returns the number
 * of errors or OK if everything is fine.
 */
int acl_find_targets(struct proxy *p);

/* Return a pointer to the ACL <name> within the list starting at <head>, or
 * NULL if not found.
 */
struct acl *find_acl_by_name(const char *name, struct list *head);

/* This function execute the match part of the acl.
 * it return ACL_PAT_FAIL, ACL_PAT_MISS or ACL_PAT_PASS
 */
inline int acl_exec_match(struct acl_expr *expr, struct sample *smp);

/*
 * Registers the ACL keyword list <kwl> as a list of valid keywords for next
 * parsing sessions.
 */
void acl_register_keywords(struct acl_kw_list *kwl);

/*
 * Unregisters the ACL keyword list <kwl> from the list of valid keywords.
 */
void acl_unregister_keywords(struct acl_kw_list *kwl);

/* initializes ACLs by resolving the sample fetch names they rely upon.
 * Returns 0 on success, otherwise an error.
 */
int init_acl();


/*
 *
 * The following functions are general purpose ACL matching functions.
 *
 */


/* ignore the current line */
int acl_parse_nothing(const char **text, struct acl_pattern *pattern, int *opaque, char **err);

/* NB: For two strings to be identical, it is required that their lengths match */
int acl_match_str(struct sample *smp, struct acl_pattern *pattern);

/* NB: For two binary buffers to be identical, it is required that their lengths match */
int acl_match_bin(struct sample *smp, struct acl_pattern *pattern);

/* Checks that the length of the pattern in <test> is included between min and max */
int acl_match_len(struct sample *smp, struct acl_pattern *pattern);

/* Checks that the integer in <test> is included between min and max */
int acl_match_int(struct sample *smp, struct acl_pattern *pattern);

/* Parse an integer. It is put both in min and max. */
int acl_parse_int(const char **text, struct acl_pattern *pattern, int *opaque, char **err);

/* Parse an version. It is put both in min and max. */
int acl_parse_dotted_ver(const char **text, struct acl_pattern *pattern, int *opaque, char **err);

/* Parse a range of integers delimited by either ':' or '-'. If only one
 * integer is read, it is set as both min and max.
 */
int acl_parse_range(const char **text, struct acl_pattern *pattern, int *opaque, char **err);

/* Parse a string. It is allocated and duplicated. */
int acl_parse_str(const char **text, struct acl_pattern *pattern, int *opaque, char **err);

/* Parse a hexa binary definition. It is allocated and duplicated. */
int acl_parse_bin(const char **text, struct acl_pattern *pattern, int *opaque, char **err);

/* Parse and concatenate strings into one. It is allocated and duplicated. */
int acl_parse_strcat(const char **text, struct acl_pattern *pattern, int *opaque, char **err);

/* Parse a regex. It is allocated. */
int acl_parse_reg(const char **text, struct acl_pattern *pattern, int *opaque, char **err);

/* Parse an IP address and an optional mask in the form addr[/mask].
 * The addr may either be an IPv4 address or a hostname. The mask
 * may either be a dotted mask or a number of bits. Returns 1 if OK,
 * otherwise 0.
 */
int acl_parse_ip(const char **text, struct acl_pattern *pattern, int *opaque, char **err);

/* always return false */
int acl_match_nothing(struct sample *smp, struct acl_pattern *pattern);

/* Checks that the pattern matches the end of the tested string. */
int acl_match_end(struct sample *smp, struct acl_pattern *pattern);

/* Checks that the pattern matches the beginning of the tested string. */
int acl_match_beg(struct sample *smp, struct acl_pattern *pattern);

/* Checks that the pattern is included inside the tested string. */
int acl_match_sub(struct sample *smp, struct acl_pattern *pattern);

/* Checks that the pattern is included inside the tested string, but enclosed
 * between slashes or at the beginning or end of the string. Slashes at the
 * beginning or end of the pattern are ignored.
 */
int acl_match_dir(struct sample *smp, struct acl_pattern *pattern);

/* Checks that the pattern is included inside the tested string, but enclosed
 * between dots or at the beginning or end of the string. Dots at the beginning
 * or end of the pattern are ignored.
 */
int acl_match_dom(struct sample *smp, struct acl_pattern *pattern);

/* Check that the IPv4 address in <test> matches the IP/mask in pattern */
int acl_match_ip(struct sample *smp, struct acl_pattern *pattern);

/* Executes a regex. It temporarily changes the data to add a trailing zero,
 * and restores the previous character when leaving.
 */
int acl_match_reg(struct sample *smp, struct acl_pattern *pattern);

#endif /* _PROTO_ACL_H */

/*
 * Local variables:
 *  c-indent-level: 8
 *  c-basic-offset: 8
 * End:
 */