/*      $OpenBSD: syntax.c,v 1.5 2017/05/28 15:48:49 jmatthew Exp $ */

/*
 * Copyright (c) 2010 Martin Hedenfalk <martin@bzero.se>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>
#include <sys/queue.h>
#include <sys/tree.h>

#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "schema.h"
#include "uuid.h"

#define SYNTAX_DECL(TYPE) \
        static int syntax_is_##TYPE(struct schema *schema, char *value, size_t len)

SYNTAX_DECL(bit_string);
SYNTAX_DECL(boolean);
SYNTAX_DECL(country);
SYNTAX_DECL(directory_string);
SYNTAX_DECL(dn);
SYNTAX_DECL(gentime);
SYNTAX_DECL(ia5_string);
SYNTAX_DECL(integer);
SYNTAX_DECL(numeric_string);
SYNTAX_DECL(octet_string);
SYNTAX_DECL(oid);
SYNTAX_DECL(printable_string);
SYNTAX_DECL(utctime);
SYNTAX_DECL(uuid);

static struct syntax syntaxes[] = {
        /*
         * Keep these sorted.
         */
        { "1.3.6.1.1.1.0.0", "NIS netgroup triple", NULL },
        { "1.3.6.1.1.1.0.1", "Boot parameter", NULL },
        { "1.3.6.1.1.16.1", "UUID", syntax_is_uuid },
        { "1.3.6.1.4.1.1466.115.121.1.11", "Country String", syntax_is_country },
        { "1.3.6.1.4.1.1466.115.121.1.12", "DN", syntax_is_dn },
        { "1.3.6.1.4.1.1466.115.121.1.14", "Delivery Method", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.15", "Directory String", syntax_is_directory_string },
        { "1.3.6.1.4.1.1466.115.121.1.16", "DIT Content Rule Description", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.17", "DIT Structure Rule Description", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.21", "Enhanced Guide", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.22", "Facsimile Telephone Number", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.23", "Fax", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.24", "Generalized Time", syntax_is_gentime },
        { "1.3.6.1.4.1.1466.115.121.1.25", "Guide", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.26", "IA5 String", syntax_is_ia5_string },
        { "1.3.6.1.4.1.1466.115.121.1.27", "INTEGER", syntax_is_integer },
        { "1.3.6.1.4.1.1466.115.121.1.28", "JPEG", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.3",  "Attribute Type Description", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.30", "Matching Rule Description", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.31", "Matching Rule Use Description", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.34", "Name And Optional UID", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.35", "Name Form Description", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.36", "Numeric String", syntax_is_numeric_string },
        { "1.3.6.1.4.1.1466.115.121.1.37", "Object Class Description", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.38", "OID", syntax_is_oid },
        { "1.3.6.1.4.1.1466.115.121.1.39", "Other Mailbox", syntax_is_ia5_string },
        { "1.3.6.1.4.1.1466.115.121.1.40", "Octet String", syntax_is_octet_string },
        { "1.3.6.1.4.1.1466.115.121.1.41", "Postal Address", syntax_is_directory_string },
        { "1.3.6.1.4.1.1466.115.121.1.44", "Printable String", syntax_is_printable_string },
        { "1.3.6.1.4.1.1466.115.121.1.45", "Subtree Specification", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.5",  "Binary", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.50", "Telephone Number", syntax_is_printable_string },
        { "1.3.6.1.4.1.1466.115.121.1.51", "Teletex Terminal Identifier", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.52", "Telex Number", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.53", "UTC Time", syntax_is_utctime },
        { "1.3.6.1.4.1.1466.115.121.1.54", "LDAP Syntax Description", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.58", "Substring Assertion", NULL },
        { "1.3.6.1.4.1.1466.115.121.1.6",  "Bit String", syntax_is_bit_string },
        { "1.3.6.1.4.1.1466.115.121.1.7",  "Boolean", syntax_is_boolean },
        { "1.3.6.1.4.1.1466.115.121.1.8",  "Certificate", NULL },

};

static int
syntax_cmp(const void *k, const void *e)
{
        return (strcmp(k, ((const struct syntax *)e)->oid));
}

const struct syntax *
syntax_lookup(const char *oid)
{
        return bsearch(oid, syntaxes, sizeof(syntaxes)/sizeof(syntaxes[0]),
            sizeof(syntaxes[0]), syntax_cmp);
}

/*
 * A value of the Octet String syntax is a sequence of zero, one, or
 * more arbitrary octets.
 */
static int
syntax_is_octet_string(struct schema *schema, char *value, size_t len)
{
        return 1;
}

/*
 * A string of one or more arbitrary UTF-8 characters.
 */
static int
syntax_is_directory_string(struct schema *schema, char *value, size_t len)
{
        /* FIXME: validate UTF-8 characters. */
        return len >= 1 && *value != '\0';
}

/*
 * A value of the Printable String syntax is a string of one or more
 * latin alphabetic, numeric, and selected punctuation characters as
 * specified by the <PrintableCharacter> rule in Section 3.2.
 *
 *    PrintableCharacter = ALPHA / DIGIT / SQUOTE / LPAREN / RPAREN /
 *                         PLUS / COMMA / HYPHEN / DOT / EQUALS /
 *                         SLASH / COLON / QUESTION / SPACE
 */
static int
syntax_is_printable_string(struct schema *schema, char *value, size_t len)
{
        static char     *special = "'()+,-.=/:? ";
        char            *p;

        for (p = value; len > 0 && *p != '\0'; p++, len--) {
                if (!isalnum((unsigned char)*p) && strchr(special, *p) == NULL)
                        return 0;
        }

        return (p != value);
}

/*
 * A value of the IA5 String syntax is a string of zero, one, or more
 * characters from International Alphabet 5 (IA5).
 *   IA5String          = *(%x00-7F)
 */
static int
syntax_is_ia5_string(struct schema *schema, char *value, size_t len)
{
        char            *p;

        for (p = value; *p != '\0'; p++) {
                if ((unsigned char)*p > 0x7F)
                        return 0;
        }

        return 1;
}

/*
 * A value of the Integer syntax is a whole number of unlimited magnitude.
 *   Integer = ( HYPHEN LDIGIT *DIGIT ) / number
 *   number  = DIGIT / ( LDIGIT 1*DIGIT )
 */
static int
syntax_is_integer(struct schema *schema, char *value, size_t len)
{
        if (*value == '-')
                value++;
        if (*value == '0')
                return value[1] == '\0';
        for (value++; *value != '\0'; value++)
                if (!isdigit((unsigned char)*value))
                        return 0;
        return 1;
}

static int
syntax_is_dn(struct schema *schema, char *value, size_t len)
{
        if (!syntax_is_directory_string(schema, value, len))
                return 0;

        /* FIXME: DN syntax not implemented */

        return 1;
}

static int
syntax_is_oid(struct schema *schema, char *value, size_t len)
{
        char    *symoid = NULL;

        if (len == 0 || *value == '\0')
                return 0;
        if (is_oidstr(value))
                return 1;

        /*
         * Check for a symbolic OID: object class, attribute type or symoid.
         */
        if (lookup_object_by_name(schema, value) != NULL ||
            lookup_attribute_by_name(schema, value) != NULL ||
            (symoid = lookup_symbolic_oid(schema, value)) != NULL) {
                free(symoid);
                return 1;
        }

        return 0;
}

static int
syntax_is_uuid(struct schema *schema, char *value, size_t len)
{
        int      i;

        if (len != 36)
                return 0;

#define IS_XDIGITS(n, c)                                \
        do {                                            \
                for (i = 0; i < (n); i++)               \
                        if (!isxdigit(*value++))        \
                                return 0;               \
                if (*value++ != (c))                    \
                        return 0;                       \
        } while(0)

        IS_XDIGITS(8, '-');
        IS_XDIGITS(4, '-');
        IS_XDIGITS(4, '-');
        IS_XDIGITS(4, '-');
        IS_XDIGITS(12, '\0');

        return 1;
}

/*
 * NumericString = 1*(DIGIT / SPACE)
 */
static int
syntax_is_numeric_string(struct schema *schema, char *value, size_t len)
{
        char    *p;

        for (p = value; *p != '\0'; p++)
                if (!isdigit((unsigned char)*p) || *p != ' ')
                        return 0;

        return p != value;
}

static int
syntax_is_time(struct schema *schema, char *value, size_t len, int gen)
{
        int      n;
        char    *p = value;

#define CHECK_RANGE(min, max) \
        do {                                            \
                if (!isdigit((unsigned char)p[0]) ||    \
                    !isdigit((unsigned char)p[1]))      \
                        return 0;                       \
                n = (p[0] - '0') * 10 + (p[1] - '0');   \
                if (n < min || n > max)                 \
                        return 0;                       \
                p += 2;                                 \
        } while (0)

        if (gen)
                CHECK_RANGE(0, 99);             /* century */
        CHECK_RANGE(0, 99);                     /* year */
        CHECK_RANGE(1, 12);                     /* month */
        CHECK_RANGE(1, 31);                     /* day */
        /* FIXME: should check number of days in month */
        CHECK_RANGE(0, 23);                     /* hour */

        if (!gen || isdigit((unsigned char)*p)) {
                CHECK_RANGE(0, 59);             /* minute */
                if (isdigit((unsigned char)*p))
                        CHECK_RANGE(0, 59+gen); /* second or leap-second */
                if (!gen && *p == '\0')
                        return 1;
        }
                                                /* fraction */
        if (!gen && ((*p == ',' || *p == '.') &&
            !isdigit((unsigned char)*++p)))
                return 0;

        if (*p == '-' || *p == '+') {
                ++p;
                CHECK_RANGE(0, 23);             /* hour */
                if (!gen || isdigit((unsigned char)*p))
                        CHECK_RANGE(0, 59);     /* minute */
        } else if (*p++ != 'Z')
                return 0;

        return *p == '\0';
}

static int
syntax_is_gentime(struct schema *schema, char *value, size_t len)
{
        return syntax_is_time(schema, value, len, 1);
}

static int
syntax_is_utctime(struct schema *schema, char *value, size_t len)
{
        return syntax_is_time(schema, value, len, 0);
}

static int
syntax_is_country(struct schema *schema, char *value, size_t len)
{
        if (len != 2)
                return 0;
        return syntax_is_printable_string(schema, value, len);
}

static int
syntax_is_bit_string(struct schema *schema, char *value, size_t len)
{
        if (*value++ != '\'')
                return 0;

        for (; *value != '\0'; value++) {
                if (*value == '\'')
                        break;
                if (*value != '0' && *value != '1')
                        return 0;
        }

        if (++*value != 'B')
                return 0;

        return *value == '\0';
}

static int
syntax_is_boolean(struct schema *schema, char *value, size_t len)
{
        return strcmp(value, "TRUE") == 0 || strcmp(value, "FALSE") == 0;
}