asn1_lib.c

/* crypto/asn1/asn1_lib.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 *
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 *
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 *
 * 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 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 acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 *
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS 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 AUTHOR OR 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.
 *
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

#include <stdio.h>
#include <limits.h>
#include "cryptlib.h"
#include <openssl/asn1.h>
#include <openssl/asn1_mac.h>

static int asn1_get_length(const unsigned char **pp, int *inf, long *rl,
                           long max);
static void asn1_put_length(unsigned char **pp, int length);
const char ASN1_version[] = "ASN.1" OPENSSL_VERSION_PTEXT;

static int _asn1_check_infinite_end(const unsigned char **p, long len)
{
    /*
     * If there is 0 or 1 byte left, the length check should pick things up
     */
    if (len <= 0)
        return (1);
    else if ((len >= 2) && ((*p)[0] == 0) && ((*p)[1] == 0)) {
        (*p) += 2;
        return (1);
    }
    return (0);
}

int ASN1_check_infinite_end(unsigned char **p, long len)
{
    return _asn1_check_infinite_end((const unsigned char **)p, len);
}

int ASN1_const_check_infinite_end(const unsigned char **p, long len)
{
    return _asn1_check_infinite_end(p, len);
}

int ASN1_get_object(const unsigned char **pp, long *plength, int *ptag,
                    int *pclass, long omax)
{
    int i, ret;
    long l;
    const unsigned char *p = *pp;
    int tag, xclass, inf;
    long max = omax;

    if (!max)
        goto err;
    ret = (*p & V_ASN1_CONSTRUCTED);
    xclass = (*p & V_ASN1_PRIVATE);
    i = *p & V_ASN1_PRIMITIVE_TAG;
    if (i == V_ASN1_PRIMITIVE_TAG) { /* high-tag */
        p++;
        if (--max == 0)
            goto err;
        l = 0;
        while (*p & 0x80) {
            l <<= 7L;
            l |= *(p++) & 0x7f;
            if (--max == 0)
                goto err;
            if (l > (INT_MAX >> 7L))
                goto err;
        }
        l <<= 7L;
        l |= *(p++) & 0x7f;
        tag = (int)l;
        if (--max == 0)
            goto err;
    } else {
        tag = i;
        p++;
        if (--max == 0)
            goto err;
    }
    *ptag = tag;
    *pclass = xclass;
    if (!asn1_get_length(&p, &inf, plength, max))
        goto err;

    if (inf && !(ret & V_ASN1_CONSTRUCTED))
        goto err;

#if 0
    fprintf(stderr, "p=%d + *plength=%ld > omax=%ld + *pp=%d  (%d > %d)\n",
            (int)p, *plength, omax, (int)*pp, (int)(p + *plength),
            (int)(omax + *pp));

#endif
    if (*plength > (omax - (p - *pp))) {
        ASN1err(ASN1_F_ASN1_GET_OBJECT, ASN1_R_TOO_LONG);
        /*
         * Set this so that even if things are not long enough the values are
         * set correctly
         */
        ret |= 0x80;
    }
    *pp = p;
    return (ret | inf);
 err:
    ASN1err(ASN1_F_ASN1_GET_OBJECT, ASN1_R_HEADER_TOO_LONG);
    return (0x80);
}

static int asn1_get_length(const unsigned char **pp, int *inf, long *rl,
                           long max)
{
    const unsigned char *p = *pp;
    unsigned long ret = 0;
    unsigned long i;

    if (max-- < 1)
        return 0;
    if (*p == 0x80) {
        *inf = 1;
        ret = 0;
        p++;
    } else {
        *inf = 0;
        i = *p & 0x7f;
        if (*(p++) & 0x80) {
            if (i > sizeof(ret) || max < (long)i)
                return 0;
            while (i-- > 0) {
                ret <<= 8L;
                ret |= *(p++);
            }
        } else
            ret = i;
    }
    if (ret > LONG_MAX)
        return 0;
    *pp = p;
    *rl = (long)ret;
    return 1;
}

/*
 * class 0 is constructed constructed == 2 for indefinite length constructed
 */
void ASN1_put_object(unsigned char **pp, int constructed, int length, int tag,
                     int xclass)
{
    unsigned char *p = *pp;
    int i, ttag;

    i = (constructed) ? V_ASN1_CONSTRUCTED : 0;
    i |= (xclass & V_ASN1_PRIVATE);
    if (tag < 31)
        *(p++) = i | (tag & V_ASN1_PRIMITIVE_TAG);
    else {
        *(p++) = i | V_ASN1_PRIMITIVE_TAG;
        for (i = 0, ttag = tag; ttag > 0; i++)
            ttag >>= 7;
        ttag = i;
        while (i-- > 0) {
            p[i] = tag & 0x7f;
            if (i != (ttag - 1))
                p[i] |= 0x80;
            tag >>= 7;
        }
        p += ttag;
    }
    if (constructed == 2)
        *(p++) = 0x80;
    else
        asn1_put_length(&p, length);
    *pp = p;
}

int ASN1_put_eoc(unsigned char **pp)
{
    unsigned char *p = *pp;
    *p++ = 0;
    *p++ = 0;
    *pp = p;
    return 2;
}

static void asn1_put_length(unsigned char **pp, int length)
{
    unsigned char *p = *pp;
    int i, l;
    if (length <= 127)
        *(p++) = (unsigned char)length;
    else {
        l = length;
        for (i = 0; l > 0; i++)
            l >>= 8;
        *(p++) = i | 0x80;
        l = i;
        while (i-- > 0) {
            p[i] = length & 0xff;
            length >>= 8;
        }
        p += l;
    }
    *pp = p;
}

int ASN1_object_size(int constructed, int length, int tag)
{
    int ret;

    ret = length;
    ret++;
    if (tag >= 31) {
        while (tag > 0) {
            tag >>= 7;
            ret++;
        }
    }
    if (constructed == 2)
        return ret + 3;
    ret++;
    if (length > 127) {
        while (length > 0) {
            length >>= 8;
            ret++;
        }
    }
    return (ret);
}

static int _asn1_Finish(ASN1_const_CTX *c)
{
    if ((c->inf == (1 | V_ASN1_CONSTRUCTED)) && (!c->eos)) {
        if (!ASN1_const_check_infinite_end(&c->p, c->slen)) {
            c->error = ERR_R_MISSING_ASN1_EOS;
            return (0);
        }
    }
    if (((c->slen != 0) && !(c->inf & 1)) || ((c->slen < 0) && (c->inf & 1))) {
        c->error = ERR_R_ASN1_LENGTH_MISMATCH;
        return (0);
    }
    return (1);
}

int asn1_Finish(ASN1_CTX *c)
{
    return _asn1_Finish((ASN1_const_CTX *)c);
}

int asn1_const_Finish(ASN1_const_CTX *c)
{
    return _asn1_Finish(c);
}

int asn1_GetSequence(ASN1_const_CTX *c, long *length)
{
    const unsigned char *q;

    q = c->p;
    c->inf = ASN1_get_object(&(c->p), &(c->slen), &(c->tag), &(c->xclass),
                             *length);
    if (c->inf & 0x80) {
        c->error = ERR_R_BAD_GET_ASN1_OBJECT_CALL;
        return (0);
    }
    if (c->tag != V_ASN1_SEQUENCE) {
        c->error = ERR_R_EXPECTING_AN_ASN1_SEQUENCE;
        return (0);
    }
    (*length) -= (c->p - q);
    if (c->max && (*length < 0)) {
        c->error = ERR_R_ASN1_LENGTH_MISMATCH;
        return (0);
    }
    if (c->inf == (1 | V_ASN1_CONSTRUCTED))
        c->slen = *length + *(c->pp) - c->p;
    c->eos = 0;
    return (1);
}

int ASN1_STRING_copy(ASN1_STRING *dst, const ASN1_STRING *str)
{
    if (str == NULL)
        return 0;
    dst->type = str->type;
    if (!ASN1_STRING_set(dst, str->data, str->length))
        return 0;
    dst->flags = str->flags;
    return 1;
}

ASN1_STRING *ASN1_STRING_dup(const ASN1_STRING *str)
{
    ASN1_STRING *ret;
    if (!str)
        return NULL;
    ret = ASN1_STRING_new();
    if (!ret)
        return NULL;
    if (!ASN1_STRING_copy(ret, str)) {
        ASN1_STRING_free(ret);
        return NULL;
    }
    return ret;
}

int ASN1_STRING_set(ASN1_STRING *str, const void *_data, int len)
{
    unsigned char *c;
    const char *data = _data;

    if (len < 0) {
        if (data == NULL)
            return (0);
        else
            len = strlen(data);
    }
    if ((str->length < len) || (str->data == NULL)) {
        c = str->data;
        if (c == NULL)
            str->data = OPENSSL_malloc(len + 1);
        else
            str->data = OPENSSL_realloc(c, len + 1);

        if (str->data == NULL) {
            ASN1err(ASN1_F_ASN1_STRING_SET, ERR_R_MALLOC_FAILURE);
            str->data = c;
            return (0);
        }
    }
    str->length = len;
    if (data != NULL) {
        memcpy(str->data, data, len);
        /* an allowance for strings :-) */
        str->data[len] = '\0';
    }
    return (1);
}

void ASN1_STRING_set0(ASN1_STRING *str, void *data, int len)
{
    if (str->data)
        OPENSSL_free(str->data);
    str->data = data;
    str->length = len;
}

ASN1_STRING *ASN1_STRING_new(void)
{
    return (ASN1_STRING_type_new(V_ASN1_OCTET_STRING));
}

ASN1_STRING *ASN1_STRING_type_new(int type)
{
    ASN1_STRING *ret;

    ret = (ASN1_STRING *)OPENSSL_malloc(sizeof(ASN1_STRING));
    if (ret == NULL) {
        ASN1err(ASN1_F_ASN1_STRING_TYPE_NEW, ERR_R_MALLOC_FAILURE);
        return (NULL);
    }
    ret->length = 0;
    ret->type = type;
    ret->data = NULL;
    ret->flags = 0;
    return (ret);
}

void ASN1_STRING_free(ASN1_STRING *a)
{
    if (a == NULL)
        return;
    if (a->data && !(a->flags & ASN1_STRING_FLAG_NDEF))
        OPENSSL_free(a->data);
    OPENSSL_free(a);
}

void ASN1_STRING_clear_free(ASN1_STRING *a)
{
    if (a && a->data && !(a->flags & ASN1_STRING_FLAG_NDEF))
        OPENSSL_cleanse(a->data, a->length);
    ASN1_STRING_free(a);
}

int ASN1_STRING_cmp(const ASN1_STRING *a, const ASN1_STRING *b)
{
    int i;

    i = (a->length - b->length);
    if (i == 0) {
        i = memcmp(a->data, b->data, a->length);
        if (i == 0)
            return (a->type - b->type);
        else
            return (i);
    } else
        return (i);
}

void asn1_add_error(const unsigned char *address, int offset)
{
    char buf1[DECIMAL_SIZE(address) + 1], buf2[DECIMAL_SIZE(offset) + 1];

    BIO_snprintf(buf1, sizeof buf1, "%lu", (unsigned long)address);
    BIO_snprintf(buf2, sizeof buf2, "%d", offset);
    ERR_add_error_data(4, "address=", buf1, " offset=", buf2);
}

int ASN1_STRING_length(const ASN1_STRING *x)
{
    return M_ASN1_STRING_length(x);
}

void ASN1_STRING_length_set(ASN1_STRING *x, int len)
{
    M_ASN1_STRING_length_set(x, len);
    return;
}

int ASN1_STRING_type(ASN1_STRING *x)
{
    return M_ASN1_STRING_type(x);
}

unsigned char *ASN1_STRING_data(ASN1_STRING *x)
{
    return M_ASN1_STRING_data(x);
}