a_mbstr.c

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/* a_mbstr.c */
/* Written by Dr Stephen N Henson ([email protected]) for the OpenSSL
 * project 1999.
 */
/* ====================================================================
 * Copyright (c) 1999 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    [email protected].
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * ([email protected]).  This product includes software written by Tim
 * Hudson ([email protected]).
 *
 */

#include <stdio.h>
#include <ctype.h>
#include "cryptlib.h"
#include <openssl/asn1.h>

static int traverse_string(const unsigned char *p, int len, int inform,
         int (*rfunc)(unsigned long value, void *in), void *arg);
static int in_utf8(unsigned long value, void *arg);
static int out_utf8(unsigned long value, void *arg);
static int type_str(unsigned long value, void *arg);
static int cpy_asc(unsigned long value, void *arg);
static int cpy_bmp(unsigned long value, void *arg);
static int cpy_univ(unsigned long value, void *arg);
static int cpy_utf8(unsigned long value, void *arg);
static int is_printable(unsigned long value);

/* These functions take a string in UTF8, ASCII or multibyte form and
 * a mask of permissible ASN1 string types. It then works out the minimal
 * type (using the order Printable < IA5 < T61 < BMP < Universal < UTF8)
 * and creates a string of the correct type with the supplied data.
 * Yes this is horrible: it has to be :-(
 * The 'ncopy' form checks minimum and maximum size limits too.
 */

int ASN1_mbstring_copy(ASN1_STRING **out, const unsigned char *in, int len,
                    int inform, unsigned long mask)
{
    return ASN1_mbstring_ncopy(out, in, len, inform, mask, 0, 0);
}

int ASN1_mbstring_ncopy(ASN1_STRING **out, const unsigned char *in, int len,
                    int inform, unsigned long mask, 
                    long minsize, long maxsize)
{
    int str_type;
    int ret;
    char free_out;
    int outform, outlen = 0;
    ASN1_STRING *dest;
    unsigned char *p;
    int nchar;
    char strbuf[32];
    int (*cpyfunc)(unsigned long,void *) = NULL;
    if(len == -1) len = strlen((const char *)in);
    if(!mask) mask = DIRSTRING_TYPE;

    /* First do a string check and work out the number of characters */
    switch(inform) {

        case MBSTRING_BMP:
        if(len & 1) {
            ASN1err(ASN1_F_ASN1_MBSTRING_NCOPY,
                     ASN1_R_INVALID_BMPSTRING_LENGTH);
            return -1;
        }
        nchar = len >> 1;
        break;

        case MBSTRING_UNIV:
        if(len & 3) {
            ASN1err(ASN1_F_ASN1_MBSTRING_NCOPY,
                     ASN1_R_INVALID_UNIVERSALSTRING_LENGTH);
            return -1;
        }
        nchar = len >> 2;
        break;

        case MBSTRING_UTF8:
        nchar = 0;
        /* This counts the characters and does utf8 syntax checking */
        ret = traverse_string(in, len, MBSTRING_UTF8, in_utf8, &nchar);
        if(ret < 0) {
            ASN1err(ASN1_F_ASN1_MBSTRING_NCOPY,
                         ASN1_R_INVALID_UTF8STRING);
            return -1;
        }
        break;

        case MBSTRING_ASC:
        nchar = len;
        break;

        default:
        ASN1err(ASN1_F_ASN1_MBSTRING_NCOPY, ASN1_R_UNKNOWN_FORMAT);
        return -1;
    }

    if((minsize > 0) && (nchar < minsize)) {
        ASN1err(ASN1_F_ASN1_MBSTRING_NCOPY, ASN1_R_STRING_TOO_SHORT);
        BIO_snprintf(strbuf, sizeof strbuf, "%ld", minsize);
        ERR_add_error_data(2, "minsize=", strbuf);
        return -1;
    }

    if((maxsize > 0) && (nchar > maxsize)) {
        ASN1err(ASN1_F_ASN1_MBSTRING_NCOPY, ASN1_R_STRING_TOO_LONG);
        BIO_snprintf(strbuf, sizeof strbuf, "%ld", maxsize);
        ERR_add_error_data(2, "maxsize=", strbuf);
        return -1;
    }

    /* Now work out minimal type (if any) */
    if(traverse_string(in, len, inform, type_str, &mask) < 0) {
        ASN1err(ASN1_F_ASN1_MBSTRING_NCOPY, ASN1_R_ILLEGAL_CHARACTERS);
        return -1;
    }


    /* Now work out output format and string type */
    outform = MBSTRING_ASC;
    if(mask & B_ASN1_PRINTABLESTRING) str_type = V_ASN1_PRINTABLESTRING;
    else if(mask & B_ASN1_IA5STRING) str_type = V_ASN1_IA5STRING;
    else if(mask & B_ASN1_T61STRING) str_type = V_ASN1_T61STRING;
    else if(mask & B_ASN1_BMPSTRING) {
        str_type = V_ASN1_BMPSTRING;
        outform = MBSTRING_BMP;
    } else if(mask & B_ASN1_UNIVERSALSTRING) {
        str_type = V_ASN1_UNIVERSALSTRING;
        outform = MBSTRING_UNIV;
    } else {
        str_type = V_ASN1_UTF8STRING;
        outform = MBSTRING_UTF8;
    }
    if(!out) return str_type;
    if(*out) {
        free_out = 0;
        dest = *out;
        if(dest->data) {
            dest->length = 0;
            OPENSSL_free(dest->data);
            dest->data = NULL;
        }
        dest->type = str_type;
    } else {
        free_out = 1;
        dest = ASN1_STRING_type_new(str_type);
        if(!dest) {
            ASN1err(ASN1_F_ASN1_MBSTRING_NCOPY,
                            ERR_R_MALLOC_FAILURE);
            return -1;
        }
        *out = dest;
    }
    /* If both the same type just copy across */
    if(inform == outform) {
        if(!ASN1_STRING_set(dest, in, len)) {
            ASN1err(ASN1_F_ASN1_MBSTRING_NCOPY,ERR_R_MALLOC_FAILURE);
            return -1;
        }
        return str_type;
    } 

    /* Work out how much space the destination will need */
    switch(outform) {
        case MBSTRING_ASC:
        outlen = nchar;
        cpyfunc = cpy_asc;
        break;

        case MBSTRING_BMP:
        outlen = nchar << 1;
        cpyfunc = cpy_bmp;
        break;

        case MBSTRING_UNIV:
        outlen = nchar << 2;
        cpyfunc = cpy_univ;
        break;

        case MBSTRING_UTF8:
        outlen = 0;
        traverse_string(in, len, inform, out_utf8, &outlen);
        cpyfunc = cpy_utf8;
        break;
    }
    if(!(p = OPENSSL_malloc(outlen + 1))) {
        if(free_out) ASN1_STRING_free(dest);
        ASN1err(ASN1_F_ASN1_MBSTRING_NCOPY,ERR_R_MALLOC_FAILURE);
        return -1;
    }
    dest->length = outlen;
    dest->data = p;
    p[outlen] = 0;
    traverse_string(in, len, inform, cpyfunc, &p);
    return str_type;    
}

/* This function traverses a string and passes the value of each character
 * to an optional function along with a void * argument.
 */

static int traverse_string(const unsigned char *p, int len, int inform,
         int (*rfunc)(unsigned long value, void *in), void *arg)
{
    unsigned long value;
    int ret;
    while(len) {
        if(inform == MBSTRING_ASC) {
            value = *p++;
            len--;
        } else if(inform == MBSTRING_BMP) {
            value = *p++ << 8;
            value |= *p++;
            len -= 2;
        } else if(inform == MBSTRING_UNIV) {
            value = ((unsigned long)*p++) << 24;
            value |= ((unsigned long)*p++) << 16;
            value |= *p++ << 8;
            value |= *p++;
            len -= 4;
        } else {
            ret = UTF8_getc(p, len, &value);
            if(ret < 0) return -1;
            len -= ret;
            p += ret;
        }
        if(rfunc) {
            ret = rfunc(value, arg);
            if(ret <= 0) return ret;
        }
    }
    return 1;
}

/* Various utility functions for traverse_string */

/* Just count number of characters */

static int in_utf8(unsigned long value, void *arg)
{
    int *nchar;
    nchar = arg;
    (*nchar)++;
    return 1;
}

/* Determine size of output as a UTF8 String */

static int out_utf8(unsigned long value, void *arg)
{
    int *outlen;
    outlen = arg;
    *outlen += UTF8_putc(NULL, -1, value);
    return 1;
}

/* Determine the "type" of a string: check each character against a
 * supplied "mask".
 */

static int type_str(unsigned long value, void *arg)
{
    unsigned long types;
    types = *((unsigned long *)arg);
    if((types & B_ASN1_PRINTABLESTRING) && !is_printable(value))
                    types &= ~B_ASN1_PRINTABLESTRING;
    if((types & B_ASN1_IA5STRING) && (value > 127))
                    types &= ~B_ASN1_IA5STRING;
    if((types & B_ASN1_T61STRING) && (value > 0xff))
                    types &= ~B_ASN1_T61STRING;
    if((types & B_ASN1_BMPSTRING) && (value > 0xffff))
                    types &= ~B_ASN1_BMPSTRING;
    if(!types) return -1;
    *((unsigned long *)arg) = types;
    return 1;
}

/* Copy one byte per character ASCII like strings */

static int cpy_asc(unsigned long value, void *arg)
{
    unsigned char **p, *q;
    p = arg;
    q = *p;
    *q = (unsigned char) value;
    (*p)++;
    return 1;
}

/* Copy two byte per character BMPStrings */

static int cpy_bmp(unsigned long value, void *arg)
{
    unsigned char **p, *q;
    p = arg;
    q = *p;
    *q++ = (unsigned char) ((value >> 8) & 0xff);
    *q = (unsigned char) (value & 0xff);
    *p += 2;
    return 1;
}

/* Copy four byte per character UniversalStrings */

static int cpy_univ(unsigned long value, void *arg)
{
    unsigned char **p, *q;
    p = arg;
    q = *p;
    *q++ = (unsigned char) ((value >> 24) & 0xff);
    *q++ = (unsigned char) ((value >> 16) & 0xff);
    *q++ = (unsigned char) ((value >> 8) & 0xff);
    *q = (unsigned char) (value & 0xff);
    *p += 4;
    return 1;
}

/* Copy to a UTF8String */

static int cpy_utf8(unsigned long value, void *arg)
{
    unsigned char **p;
    int ret;
    p = arg;
    /* We already know there is enough room so pass 0xff as the length */
    ret = UTF8_putc(*p, 0xff, value);
    *p += ret;
    return 1;
}

/* Return 1 if the character is permitted in a PrintableString */
static int is_printable(unsigned long value)
{
    int ch;
    if(value > 0x7f) return 0;
    ch = (int) value;
    /* Note: we can't use 'isalnum' because certain accented 
     * characters may count as alphanumeric in some environments.
     */
#ifndef CHARSET_EBCDIC
    if((ch >= 'a') && (ch <= 'z')) return 1;
    if((ch >= 'A') && (ch <= 'Z')) return 1;
    if((ch >= '0') && (ch <= '9')) return 1;
    if ((ch == ' ') || strchr("'()+,-./:=?", ch)) return 1;
#else /*CHARSET_EBCDIC*/
    if((ch >= os_toascii['a']) && (ch <= os_toascii['z'])) return 1;
    if((ch >= os_toascii['A']) && (ch <= os_toascii['Z'])) return 1;
    if((ch >= os_toascii['0']) && (ch <= os_toascii['9'])) return 1;
    if ((ch == os_toascii[' ']) || strchr("'()+,-./:=?", os_toebcdic[ch])) return 1;
#endif /*CHARSET_EBCDIC*/
    return 0;
}