/*

 * Copyright 1999-2021 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include <stdio.h>

#include "crypto/ctype.h"

#include "internal/cryptlib.h"

#include "internal/unicode.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);

/*

 * 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 Numeric < 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;

    int (*cpyfunc)(unsigned long, void *) = NULL;

    if (len == -1)

        len = strlen((const char *)in);

    if (!mask)

        mask = DIRSTRING_TYPE;

    if (len < 0)

        return -1;

    /* First do a string check and work out the number of characters */

    switch (inform) {

    case MBSTRING_BMP:

        if (len & 1) {

            ERR_raise(ERR_LIB_ASN1, ASN1_R_INVALID_BMPSTRING_LENGTH);

            return -1;

        }

        nchar = len >> 1;

        break;

    case MBSTRING_UNIV:

        if (len & 3) {

            ERR_raise(ERR_LIB_ASN1, 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) {

            ERR_raise(ERR_LIB_ASN1, ASN1_R_INVALID_UTF8STRING);

            return -1;

        }

        break;

    case MBSTRING_ASC:

        nchar = len;

        break;

    default:

        ERR_raise(ERR_LIB_ASN1, ASN1_R_UNKNOWN_FORMAT);

        return -1;

    }

    if ((minsize > 0) && (nchar < minsize)) {

        ERR_raise_data(ERR_LIB_ASN1, ASN1_R_STRING_TOO_SHORT,

            "minsize=%ld", minsize);

        return -1;

    }

    if ((maxsize > 0) && (nchar > maxsize)) {

        ERR_raise_data(ERR_LIB_ASN1, ASN1_R_STRING_TOO_LONG,

            "maxsize=%ld", maxsize);

        return -1;

    }

    /* Now work out minimal type (if any) */

    if (traverse_string(in, len, inform, type_str, &mask) < 0) {

        ERR_raise(ERR_LIB_ASN1, ASN1_R_ILLEGAL_CHARACTERS);

        return -1;

    }

    /*

     * Now work out output format and string type.

     * These checks should be in sync with the checks in type_str.

     */

    outform = MBSTRING_ASC;

    if (mask & B_ASN1_NUMERICSTRING)

        str_type = V_ASN1_NUMERICSTRING;

    else 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;

        ASN1_STRING_set0(dest, NULL, 0);

        dest->type = str_type;

    } else {

        free_out = 1;

        dest = ASN1_STRING_type_new(str_type);

        if (dest == NULL) {

            ERR_raise(ERR_LIB_ASN1, ERR_R_ASN1_LIB);

            return -1;

        }

        *out = dest;

    }

    /* If both the same type just copy across */

    if (inform == outform) {

        if (!ASN1_STRING_set(dest, in, len)) {

            if (free_out) {

                ASN1_STRING_free(dest);

                *out = NULL;

            }

            ERR_raise(ERR_LIB_ASN1, ERR_R_ASN1_LIB);

            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;

        ret = traverse_string(in, len, inform, out_utf8, &outlen);

        if (ret < 0) {

            ERR_raise(ERR_LIB_ASN1, ASN1_R_INVALID_UTF8STRING);

            return -1;

        }

        cpyfunc = cpy_utf8;

        break;

    }

    if ((p = OPENSSL_malloc(outlen + 1)) == NULL) {

        if (free_out) {

            ASN1_STRING_free(dest);

            *out = NULL;

        }

        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;

    if (!is_unicode_valid(value))

        return -2;

    nchar = arg;

    (*nchar)++;

    return 1;

}

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

static int out_utf8(unsigned long value, void *arg)

{

    int *outlen, len;

    len = UTF8_putc(NULL, -1, value);

    if (len <= 0)

        return len;

    outlen = arg;

    *outlen += len;

    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 usable_types = *((unsigned long *)arg);

    unsigned long types = usable_types;

    const int native = value > INT_MAX ? INT_MAX : ossl_fromascii(value);

    /*

     * Clear out all the types which are not checked later. If any of those

     * is present in the mask, then the UTF8 type will be added and checked

     * below.

     */

    types &= B_ASN1_NUMERICSTRING | B_ASN1_PRINTABLESTRING

        | B_ASN1_IA5STRING | B_ASN1_T61STRING | B_ASN1_BMPSTRING

        | B_ASN1_UNIVERSALSTRING | B_ASN1_UTF8STRING;

    /*

     * If any other types were in the input mask, they're effectively treated

     * as UTF8

     */

    if (types != usable_types)

        types |= B_ASN1_UTF8STRING;

    /*

     * These checks should be in sync with ASN1_mbstring_ncopy.

     */

    if ((types & B_ASN1_NUMERICSTRING) && !(ossl_isdigit(native) || native == ' '))

        types &= ~B_ASN1_NUMERICSTRING;

    if ((types & B_ASN1_PRINTABLESTRING) && !ossl_isasn1print(native))

        types &= ~B_ASN1_PRINTABLESTRING;

    if ((types & B_ASN1_IA5STRING) && !ossl_isascii(native))

        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 & B_ASN1_UTF8STRING) && !is_unicode_valid(value))

        types &= ~B_ASN1_UTF8STRING;

    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);

    if (ret < 0)

        return ret;

    *p += ret;

    return 1;

}