/src/openssl/crypto/asn1/tasn_enc.c

Source
/*
 * Copyright 2000-2025 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 <stddef.h>
#include <string.h>
#include "internal/cryptlib.h"
#include <openssl/asn1.h>
#include <openssl/asn1t.h>
#include <openssl/objects.h>
#include "crypto/asn1.h"
#include "asn1_local.h"

static int asn1_i2d_ex_primitive(const ASN1_VALUE **pval, unsigned char **out,
    const ASN1_ITEM *it, int tag, int aclass);
static int asn1_set_seq_out(STACK_OF(const_ASN1_VALUE) *sk,
    unsigned char **out,
    int skcontlen, const ASN1_ITEM *item,
    int do_sort, int iclass);
static int asn1_template_ex_i2d(const ASN1_VALUE **pval, unsigned char **out,
    const ASN1_TEMPLATE *tt, int tag, int aclass);
static int asn1_item_flags_i2d(const ASN1_VALUE *val, unsigned char **out,
    const ASN1_ITEM *it, int flags);
static int asn1_ex_i2c(const ASN1_VALUE **pval, unsigned char *cout, int *putype,
    const ASN1_ITEM *it);

/*
 * Top level i2d equivalents: the 'ndef' variant instructs the encoder to use
 * indefinite length constructed encoding, where appropriate
 */

int ASN1_item_ndef_i2d(const ASN1_VALUE *val, unsigned char **out,
    const ASN1_ITEM *it)
{
    return asn1_item_flags_i2d(val, out, it, ASN1_TFLG_NDEF);
}

int ASN1_item_i2d(const ASN1_VALUE *val, unsigned char **out, const ASN1_ITEM *it)
{
    return asn1_item_flags_i2d(val, out, it, 0);
}

/*
 * Encode an ASN1 item, this is use by the standard 'i2d' function. 'out'
 * points to a buffer to output the data to. The new i2d has one additional
 * feature. If the output buffer is NULL (i.e. *out == NULL) then a buffer is
 * allocated and populated with the encoding.
 */

static int asn1_item_flags_i2d(const ASN1_VALUE *val, unsigned char **out,
    const ASN1_ITEM *it, int flags)
{
    if (out != NULL && *out == NULL) {
        unsigned char *p, *buf;
        int len;

        len = ASN1_item_ex_i2d(&val, NULL, it, -1, flags);
        if (len <= 0)
            return len;
        if ((buf = OPENSSL_malloc(len)) == NULL)
            return -1;
        p = buf;
        ASN1_item_ex_i2d(&val, &p, it, -1, flags);
        *out = buf;
        return len;
    }

    return ASN1_item_ex_i2d(&val, out, it, -1, flags);
}

/*
 * Encode an item, taking care of IMPLICIT tagging (if any). This function
 * performs the normal item handling: it can be used in external types.
 */

int ASN1_item_ex_i2d(const ASN1_VALUE **pval, unsigned char **out,
    const ASN1_ITEM *it, int tag, int aclass)
{
    const ASN1_TEMPLATE *tt = NULL;
    int i, seqcontlen, seqlen, ndef = 1;
    const ASN1_EXTERN_FUNCS *ef;
    const ASN1_AUX *aux = it->funcs;
    ASN1_aux_const_cb *asn1_cb = NULL;

    if ((it->itype != ASN1_ITYPE_PRIMITIVE) && *pval == NULL)
        return 0;

    if (aux != NULL) {
        asn1_cb = ((aux->flags & ASN1_AFLG_CONST_CB) != 0) ? aux->asn1_const_cb
                                                           : (ASN1_aux_const_cb *)aux->asn1_cb; /* backward compatibility */
    }

    switch (it->itype) {

    case ASN1_ITYPE_PRIMITIVE:
        if (it->templates)
            return asn1_template_ex_i2d(pval, out, it->templates,
                tag, aclass);
        return asn1_i2d_ex_primitive(pval, out, it, tag, aclass);

    case ASN1_ITYPE_MSTRING:
        /*
         * It never makes sense for multi-strings to have implicit tagging, so
         * if tag != -1, then this looks like an error in the template.
         */
        if (tag != -1) {
            ERR_raise(ERR_LIB_ASN1, ASN1_R_BAD_TEMPLATE);
            return -1;
        }
        return asn1_i2d_ex_primitive(pval, out, it, -1, aclass);

    case ASN1_ITYPE_CHOICE:
        /*
         * It never makes sense for CHOICE types to have implicit tagging, so
         * if tag != -1, then this looks like an error in the template.
         */
        if (tag != -1) {
            ERR_raise(ERR_LIB_ASN1, ASN1_R_BAD_TEMPLATE);
            return -1;
        }
        if (asn1_cb && !asn1_cb(ASN1_OP_I2D_PRE, pval, it, NULL))
            return 0;
        i = ossl_asn1_get_choice_selector_const(pval, it);
        if ((i >= 0) && (i < it->tcount)) {
            const ASN1_VALUE **pchval;
            const ASN1_TEMPLATE *chtt;
            chtt = it->templates + i;
            pchval = ossl_asn1_get_const_field_ptr(pval, chtt);
            return asn1_template_ex_i2d(pchval, out, chtt, -1, aclass);
        }
        /* Fixme: error condition if selector out of range */
        if (asn1_cb && !asn1_cb(ASN1_OP_I2D_POST, pval, it, NULL))
            return 0;
        break;

    case ASN1_ITYPE_EXTERN:
        /* If new style i2d it does all the work */
        ef = it->funcs;
        return ef->asn1_ex_i2d(pval, out, it, tag, aclass);

    case ASN1_ITYPE_NDEF_SEQUENCE:
        /* Use indefinite length constructed if requested */
        if (aclass & ASN1_TFLG_NDEF)
            ndef = 2;
        /* fall through */

    case ASN1_ITYPE_SEQUENCE:
        i = ossl_asn1_enc_restore(&seqcontlen, out, pval, it);
        /* An error occurred */
        if (i < 0)
            return 0;
        /* We have a valid cached encoding... */
        if (i > 0)
            return seqcontlen;
        /* Otherwise carry on */
        seqcontlen = 0;
        /* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
        if (tag == -1) {
            tag = V_ASN1_SEQUENCE;
            /* Retain any other flags in aclass */
            aclass = (aclass & ~ASN1_TFLG_TAG_CLASS)
                | V_ASN1_UNIVERSAL;
        }
        if (asn1_cb && !asn1_cb(ASN1_OP_I2D_PRE, pval, it, NULL))
            return 0;
        /* First work out sequence content length */
        for (i = 0, tt = it->templates; i < it->tcount; tt++, i++) {
            const ASN1_TEMPLATE *seqtt;
            const ASN1_VALUE **pseqval;
            int tmplen;
            seqtt = ossl_asn1_do_adb(*pval, tt, 1);
            if (!seqtt)
                return 0;
            pseqval = ossl_asn1_get_const_field_ptr(pval, seqtt);
            tmplen = asn1_template_ex_i2d(pseqval, NULL, seqtt, -1, aclass);
            if (tmplen == -1 || (tmplen > INT_MAX - seqcontlen))
                return -1;
            seqcontlen += tmplen;
        }

        seqlen = ASN1_object_size(ndef, seqcontlen, tag);
        if (!out || seqlen == -1)
            return seqlen;
        /* Output SEQUENCE header */
        ASN1_put_object(out, ndef, seqcontlen, tag, aclass);
        for (i = 0, tt = it->templates; i < it->tcount; tt++, i++) {
            const ASN1_TEMPLATE *seqtt;
            const ASN1_VALUE **pseqval;
            seqtt = ossl_asn1_do_adb(*pval, tt, 1);
            if (!seqtt)
                return 0;
            pseqval = ossl_asn1_get_const_field_ptr(pval, seqtt);
            /* FIXME: check for errors in enhanced version */
            asn1_template_ex_i2d(pseqval, out, seqtt, -1, aclass);
        }
        if (ndef == 2)
            ASN1_put_eoc(out);
        if (asn1_cb && !asn1_cb(ASN1_OP_I2D_POST, pval, it, NULL))
            return 0;
        return seqlen;

    default:
        return 0;
    }
    return 0;
}

static int asn1_template_ex_i2d(const ASN1_VALUE **pval, unsigned char **out,
    const ASN1_TEMPLATE *tt, int tag, int iclass)
{
    const int flags = tt->flags;
    int i, ret, ttag, tclass, ndef, len;
    const ASN1_VALUE *tval;

    /*
     * If field is embedded then val needs fixing so it is a pointer to
     * a pointer to a field.
     */
    if (flags & ASN1_TFLG_EMBED) {
        tval = (ASN1_VALUE *)pval;
        pval = &tval;
    }
    /*
     * Work out tag and class to use: tagging may come either from the
     * template or the arguments, not both because this would create
     * ambiguity. Additionally the iclass argument may contain some
     * additional flags which should be noted and passed down to other
     * levels.
     */
    if (flags & ASN1_TFLG_TAG_MASK) {
        /* Error if argument and template tagging */
        if (tag != -1)
            /* FIXME: error code here */
            return -1;
        /* Get tagging from template */
        ttag = tt->tag;
        tclass = flags & ASN1_TFLG_TAG_CLASS;
    } else if (tag != -1) {
        /* No template tagging, get from arguments */
        ttag = tag;
        tclass = iclass & ASN1_TFLG_TAG_CLASS;
    } else {
        ttag = -1;
        tclass = 0;
    }
    /*
     * Remove any class mask from iflag.
     */
    iclass &= ~ASN1_TFLG_TAG_CLASS;

    /*
     * At this point 'ttag' contains the outer tag to use, 'tclass' is the
     * class and iclass is any flags passed to this function.
     */

    /* if template and arguments require ndef, use it */
    if ((flags & ASN1_TFLG_NDEF) && (iclass & ASN1_TFLG_NDEF))
        ndef = 2;
    else
        ndef = 1;

    if (flags & ASN1_TFLG_SK_MASK) {
        /* SET OF, SEQUENCE OF */
        STACK_OF(const_ASN1_VALUE) *sk = (STACK_OF(const_ASN1_VALUE) *)*pval;
        int isset, sktag, skaclass;
        int skcontlen, sklen;
        const ASN1_VALUE *skitem;

        if (*pval == NULL)
            return 0;

        if (flags & ASN1_TFLG_SET_OF) {
            isset = 1;
            /* 2 means we reorder */
            if (flags & ASN1_TFLG_SEQUENCE_OF)
                isset = 2;
        } else
            isset = 0;

        /*
         * Work out inner tag value: if EXPLICIT or no tagging use underlying
         * type.
         */
        if ((ttag != -1) && !(flags & ASN1_TFLG_EXPTAG)) {
            sktag = ttag;
            skaclass = tclass;
        } else {
            skaclass = V_ASN1_UNIVERSAL;
            if (isset)
                sktag = V_ASN1_SET;
            else
                sktag = V_ASN1_SEQUENCE;
        }

        /* Determine total length of items */
        skcontlen = 0;
        for (i = 0; i < sk_const_ASN1_VALUE_num(sk); i++) {
            skitem = sk_const_ASN1_VALUE_value(sk, i);
            len = ASN1_item_ex_i2d(&skitem, NULL, ASN1_ITEM_ptr(tt->item),
                -1, iclass);
            if (len == -1 || (skcontlen > INT_MAX - len))
                return -1;
            if (len == 0 && (tt->flags & ASN1_TFLG_OPTIONAL) == 0) {
                ERR_raise(ERR_LIB_ASN1, ASN1_R_ILLEGAL_ZERO_CONTENT);
                return -1;
            }
            skcontlen += len;
        }
        sklen = ASN1_object_size(ndef, skcontlen, sktag);
        if (sklen == -1)
            return -1;
        /* If EXPLICIT need length of surrounding tag */
        if (flags & ASN1_TFLG_EXPTAG)
            ret = ASN1_object_size(ndef, sklen, ttag);
        else
            ret = sklen;

        if (!out || ret == -1)
            return ret;

        /* Now encode this lot... */
        /* EXPLICIT tag */
        if (flags & ASN1_TFLG_EXPTAG)
            ASN1_put_object(out, ndef, sklen, ttag, tclass);
        /* SET or SEQUENCE and IMPLICIT tag */
        ASN1_put_object(out, ndef, skcontlen, sktag, skaclass);
        /* And the stuff itself */
        asn1_set_seq_out(sk, out, skcontlen, ASN1_ITEM_ptr(tt->item),
            isset, iclass);
        if (ndef == 2) {
            ASN1_put_eoc(out);
            if (flags & ASN1_TFLG_EXPTAG)
                ASN1_put_eoc(out);
        }

        return ret;
    }

    if (flags & ASN1_TFLG_EXPTAG) {
        /* EXPLICIT tagging */
        /* Find length of tagged item */
        i = ASN1_item_ex_i2d(pval, NULL, ASN1_ITEM_ptr(tt->item), -1, iclass);
        if (i == 0) {
            if ((tt->flags & ASN1_TFLG_OPTIONAL) == 0) {
                ERR_raise(ERR_LIB_ASN1, ASN1_R_ILLEGAL_ZERO_CONTENT);
                return -1;
            }
            return 0;
        }
        /* Find length of EXPLICIT tag */
        ret = ASN1_object_size(ndef, i, ttag);
        if (out && ret != -1) {
            /* Output tag and item */
            ASN1_put_object(out, ndef, i, ttag, tclass);
            ASN1_item_ex_i2d(pval, out, ASN1_ITEM_ptr(tt->item), -1, iclass);
            if (ndef == 2)
                ASN1_put_eoc(out);
        }
        return ret;
    }

    /* Either normal or IMPLICIT tagging: combine class and flags */
    len = ASN1_item_ex_i2d(pval, out, ASN1_ITEM_ptr(tt->item),
        ttag, tclass | iclass);
    if (len == 0 && (tt->flags & ASN1_TFLG_OPTIONAL) == 0) {
        ERR_raise(ERR_LIB_ASN1, ASN1_R_ILLEGAL_ZERO_CONTENT);
        return -1;
    }
    return len;
}

/* Temporary structure used to hold DER encoding of items for SET OF */

typedef struct {
    unsigned char *data;
    int length;
    const ASN1_VALUE *field;
} DER_ENC;

static int der_cmp(const void *a, const void *b)
{
    const DER_ENC *d1 = a, *d2 = b;
    int cmplen, i;
    cmplen = (d1->length < d2->length) ? d1->length : d2->length;
    i = memcmp(d1->data, d2->data, cmplen);
    if (i)
        return i;
    return d1->length - d2->length;
}

/* Output the content octets of SET OF or SEQUENCE OF */

static int asn1_set_seq_out(STACK_OF(const_ASN1_VALUE) *sk,
    unsigned char **out,
    int skcontlen, const ASN1_ITEM *item,
    int do_sort, int iclass)
{
    int i, ret = 0;
    const ASN1_VALUE *skitem;
    unsigned char *tmpdat = NULL, *p = NULL;
    DER_ENC *derlst = NULL, *tder;

    if (do_sort) {
        /* Don't need to sort less than 2 items */
        if (sk_const_ASN1_VALUE_num(sk) < 2)
            do_sort = 0;
        else {
            derlst = OPENSSL_malloc(sk_const_ASN1_VALUE_num(sk)
                * sizeof(*derlst));
            if (derlst == NULL)
                return 0;
            tmpdat = OPENSSL_malloc(skcontlen);
            if (tmpdat == NULL)
                goto err;
        }
    }
    /* If not sorting just output each item */
    if (!do_sort) {
        for (i = 0; i < sk_const_ASN1_VALUE_num(sk); i++) {
            skitem = sk_const_ASN1_VALUE_value(sk, i);
            ASN1_item_ex_i2d(&skitem, out, item, -1, iclass);
        }
        return 1;
    }
    p = tmpdat;

    /* Doing sort: build up a list of each member's DER encoding */
    for (i = 0, tder = derlst; i < sk_const_ASN1_VALUE_num(sk); i++, tder++) {
        skitem = sk_const_ASN1_VALUE_value(sk, i);
        tder->data = p;
        tder->length = ASN1_item_ex_i2d(&skitem, &p, item, -1, iclass);
        tder->field = skitem;
    }

    /* Now sort them */
    qsort(derlst, sk_const_ASN1_VALUE_num(sk), sizeof(*derlst), der_cmp);
    /* Output sorted DER encoding */
    p = *out;
    for (i = 0, tder = derlst; i < sk_const_ASN1_VALUE_num(sk); i++, tder++) {
        memcpy(p, tder->data, tder->length);
        p += tder->length;
    }
    *out = p;
    /* If do_sort is 2 then reorder the STACK */
    if (do_sort == 2) {
        for (i = 0, tder = derlst; i < sk_const_ASN1_VALUE_num(sk); i++, tder++)
            (void)sk_const_ASN1_VALUE_set(sk, i, tder->field);
    }
    ret = 1;
err:
    OPENSSL_free(derlst);
    OPENSSL_free(tmpdat);
    return ret;
}

static int asn1_i2d_ex_primitive(const ASN1_VALUE **pval, unsigned char **out,
    const ASN1_ITEM *it, int tag, int aclass)
{
    int len;
    int utype;
    int usetag;
    int ndef = 0;

    utype = it->utype;

    /*
     * Get length of content octets and maybe find out the underlying type.
     */

    len = asn1_ex_i2c(pval, NULL, &utype, it);

    /*
     * If SEQUENCE, SET or OTHER then header is included in pseudo content
     * octets so don't include tag+length. We need to check here because the
     * call to asn1_ex_i2c() could change utype.
     */
    if ((utype == V_ASN1_SEQUENCE) || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER))
        usetag = 0;
    else
        usetag = 1;

    /* -1 means omit type */

    if (len == -1)
        return 0;

    /* -2 return is special meaning use ndef */
    if (len == -2) {
        ndef = 2;
        len = 0;
    }

    /* If not implicitly tagged get tag from underlying type */
    if (tag == -1)
        tag = utype;

    /* Output tag+length followed by content octets */
    if (out) {
        if (usetag)
            ASN1_put_object(out, ndef, len, tag, aclass);
        asn1_ex_i2c(pval, *out, &utype, it);
        if (ndef)
            ASN1_put_eoc(out);
        else
            *out += len;
    }

    if (usetag)
        return ASN1_object_size(ndef, len, tag);
    return len;
}

/* Produce content octets from a structure */

static int asn1_ex_i2c(const ASN1_VALUE **pval, unsigned char *cout, int *putype,
    const ASN1_ITEM *it)
{
    ASN1_BOOLEAN *tbool = NULL;
    ASN1_STRING *strtmp;
    ASN1_OBJECT *otmp;
    int utype;
    const unsigned char *cont;
    unsigned char c;
    int len;
    const ASN1_PRIMITIVE_FUNCS *pf;
    pf = it->funcs;
    if (pf && pf->prim_i2c)
        return pf->prim_i2c(pval, cout, putype, it);

    /* Should type be omitted? */
    if ((it->itype != ASN1_ITYPE_PRIMITIVE)
        || (it->utype != V_ASN1_BOOLEAN)) {
        if (*pval == NULL)
            return -1;
    }

    if (it->itype == ASN1_ITYPE_MSTRING) {
        /* If MSTRING type set the underlying type */
        strtmp = (ASN1_STRING *)*pval;
        utype = strtmp->type;
        *putype = utype;
    } else if (it->utype == V_ASN1_ANY) {
        /* If ANY set type and pointer to value */
        ASN1_TYPE *typ;
        typ = (ASN1_TYPE *)*pval;
        utype = typ->type;
        *putype = utype;
        pval = (const ASN1_VALUE **)&typ->value.asn1_value; /* actually is const */
    } else
        utype = *putype;

    switch (utype) {
    case V_ASN1_OBJECT:
        otmp = (ASN1_OBJECT *)*pval;
        cont = otmp->data;
        len = otmp->length;
        if (cont == NULL || len == 0)
            return -1;
        break;

    case V_ASN1_UNDEF:
        return -2;

    case V_ASN1_NULL:
        cont = NULL;
        len = 0;
        break;

    case V_ASN1_BOOLEAN:
        tbool = (ASN1_BOOLEAN *)pval;
        if (*tbool == -1)
            return -1;
        if (it->utype != V_ASN1_ANY) {
            /*
             * Default handling if value == size field then omit
             */
            if (*tbool && (it->size > 0))
                return -1;
            if (!*tbool && !it->size)
                return -1;
        }
        c = (unsigned char)*tbool;
        cont = &c;
        len = 1;
        break;

    case V_ASN1_BIT_STRING:
        return ossl_i2c_ASN1_BIT_STRING((ASN1_BIT_STRING *)*pval,
            cout ? &cout : NULL);

    case V_ASN1_INTEGER:
    case V_ASN1_ENUMERATED:
        /*
         * These are all have the same content format as ASN1_INTEGER
         */
        return ossl_i2c_ASN1_INTEGER((ASN1_INTEGER *)*pval, cout ? &cout : NULL);

    case V_ASN1_OCTET_STRING:
    case V_ASN1_NUMERICSTRING:
    case V_ASN1_PRINTABLESTRING:
    case V_ASN1_T61STRING:
    case V_ASN1_VIDEOTEXSTRING:
    case V_ASN1_IA5STRING:
    case V_ASN1_UTCTIME:
    case V_ASN1_GENERALIZEDTIME:
    case V_ASN1_GRAPHICSTRING:
    case V_ASN1_VISIBLESTRING:
    case V_ASN1_GENERALSTRING:
    case V_ASN1_UNIVERSALSTRING:
    case V_ASN1_BMPSTRING:
    case V_ASN1_UTF8STRING:
    case V_ASN1_SEQUENCE:
    case V_ASN1_SET:
    default:
        /* All based on ASN1_STRING and handled the same */
        strtmp = (ASN1_STRING *)*pval;
        /* Special handling for NDEF */
        if ((it->size == ASN1_TFLG_NDEF)
            && (strtmp->flags & ASN1_STRING_FLAG_NDEF)) {
            if (cout) {
                strtmp->data = cout;
                strtmp->length = 0;
            }
            /* Special return code */
            return -2;
        }
        cont = strtmp->data;
        len = strtmp->length;

        break;
    }
    if (cout && len)
        memcpy(cout, cont, len);
    return len;
}

Coverage Report

Created: 2025-12-10 06:24

Line	Count	Source
1		/*
2		* Copyright 2000-2025 The OpenSSL Project Authors. All Rights Reserved.
3		*
4		* Licensed under the Apache License 2.0 (the "License"). You may not use
5		* this file except in compliance with the License. You can obtain a copy
6		* in the file LICENSE in the source distribution or at
7		* https://www.openssl.org/source/license.html
8		*/
9
10		#include <stddef.h>
11		#include <string.h>
12		#include "internal/cryptlib.h"
13		#include <openssl/asn1.h>
14		#include <openssl/asn1t.h>
15		#include <openssl/objects.h>
16		#include "crypto/asn1.h"
17		#include "asn1_local.h"
18
19		static int asn1_i2d_ex_primitive(const ASN1_VALUE pval, unsigned char out,
20		const ASN1_ITEM *it, int tag, int aclass);
21		static int asn1_set_seq_out(STACK_OF(const_ASN1_VALUE) *sk,
22		unsigned char **out,
23		int skcontlen, const ASN1_ITEM *item,
24		int do_sort, int iclass);
25		static int asn1_template_ex_i2d(const ASN1_VALUE pval, unsigned char out,
26		const ASN1_TEMPLATE *tt, int tag, int aclass);
27		static int asn1_item_flags_i2d(const ASN1_VALUE val, unsigned char *out,
28		const ASN1_ITEM *it, int flags);
29		static int asn1_ex_i2c(const ASN1_VALUE *pval, unsigned char cout, int *putype,
30		const ASN1_ITEM *it);
31
32		/*
33		* Top level i2d equivalents: the 'ndef' variant instructs the encoder to use
34		* indefinite length constructed encoding, where appropriate
35		*/
36
37		int ASN1_item_ndef_i2d(const ASN1_VALUE val, unsigned char *out,
38		const ASN1_ITEM *it)
39	0	{
40	0	return asn1_item_flags_i2d(val, out, it, ASN1_TFLG_NDEF);
41	0	}
42
43		int ASN1_item_i2d(const ASN1_VALUE val, unsigned char out, const ASN1_ITEM it)
44	0	{
45	0	return asn1_item_flags_i2d(val, out, it, 0);
46	0	}
47
48		/*
49		* Encode an ASN1 item, this is use by the standard 'i2d' function. 'out'
50		* points to a buffer to output the data to. The new i2d has one additional
51		* feature. If the output buffer is NULL (i.e. *out == NULL) then a buffer is
52		* allocated and populated with the encoding.
53		*/
54
55		static int asn1_item_flags_i2d(const ASN1_VALUE val, unsigned char *out,
56		const ASN1_ITEM *it, int flags)
57	0	{
58	0	if (out != NULL && *out == NULL) {
59	0	unsigned char p, buf;
60	0	int len;
61
62	0	len = ASN1_item_ex_i2d(&val, NULL, it, -1, flags);
63	0	if (len <= 0)
64	0	return len;
65	0	if ((buf = OPENSSL_malloc(len)) == NULL)
66	0	return -1;
67	0	p = buf;
68	0	ASN1_item_ex_i2d(&val, &p, it, -1, flags);
69	0	*out = buf;
70	0	return len;
71	0	}
72
73	0	return ASN1_item_ex_i2d(&val, out, it, -1, flags);
74	0	}
75
76		/*
77		* Encode an item, taking care of IMPLICIT tagging (if any). This function
78		* performs the normal item handling: it can be used in external types.
79		*/
80
81		int ASN1_item_ex_i2d(const ASN1_VALUE pval, unsigned char out,
82		const ASN1_ITEM *it, int tag, int aclass)
83	0	{
84	0	const ASN1_TEMPLATE *tt = NULL;
85	0	int i, seqcontlen, seqlen, ndef = 1;
86	0	const ASN1_EXTERN_FUNCS *ef;
87	0	const ASN1_AUX *aux = it->funcs;
88	0	ASN1_aux_const_cb *asn1_cb = NULL;
89
90	0	if ((it->itype != ASN1_ITYPE_PRIMITIVE) && *pval == NULL)
91	0	return 0;
92
93	0	if (aux != NULL) {
94	0	asn1_cb = ((aux->flags & ASN1_AFLG_CONST_CB) != 0) ? aux->asn1_const_cb
95	0	: (ASN1_aux_const_cb )aux->asn1_cb; / backward compatibility */
96	0	}
97
98	0	switch (it->itype) {
99
100	0	case ASN1_ITYPE_PRIMITIVE:
101	0	if (it->templates)
102	0	return asn1_template_ex_i2d(pval, out, it->templates,
103	0	tag, aclass);
104	0	return asn1_i2d_ex_primitive(pval, out, it, tag, aclass);
105
106	0	case ASN1_ITYPE_MSTRING:
107		/*
108		* It never makes sense for multi-strings to have implicit tagging, so
109		* if tag != -1, then this looks like an error in the template.
110		*/
111	0	if (tag != -1) {
112	0	ERR_raise(ERR_LIB_ASN1, ASN1_R_BAD_TEMPLATE);
113	0	return -1;
114	0	}
115	0	return asn1_i2d_ex_primitive(pval, out, it, -1, aclass);
116
117	0	case ASN1_ITYPE_CHOICE:
118		/*
119		* It never makes sense for CHOICE types to have implicit tagging, so
120		* if tag != -1, then this looks like an error in the template.
121		*/
122	0	if (tag != -1) {
123	0	ERR_raise(ERR_LIB_ASN1, ASN1_R_BAD_TEMPLATE);
124	0	return -1;
125	0	}
126	0	if (asn1_cb && !asn1_cb(ASN1_OP_I2D_PRE, pval, it, NULL))
127	0	return 0;
128	0	i = ossl_asn1_get_choice_selector_const(pval, it);
129	0	if ((i >= 0) && (i < it->tcount)) {
130	0	const ASN1_VALUE **pchval;
131	0	const ASN1_TEMPLATE *chtt;
132	0	chtt = it->templates + i;
133	0	pchval = ossl_asn1_get_const_field_ptr(pval, chtt);
134	0	return asn1_template_ex_i2d(pchval, out, chtt, -1, aclass);
135	0	}
136		/* Fixme: error condition if selector out of range */
137	0	if (asn1_cb && !asn1_cb(ASN1_OP_I2D_POST, pval, it, NULL))
138	0	return 0;
139	0	break;
140
141	0	case ASN1_ITYPE_EXTERN:
142		/* If new style i2d it does all the work */
143	0	ef = it->funcs;
144	0	return ef->asn1_ex_i2d(pval, out, it, tag, aclass);
145
146	0	case ASN1_ITYPE_NDEF_SEQUENCE:
147		/* Use indefinite length constructed if requested */
148	0	if (aclass & ASN1_TFLG_NDEF)
149	0	ndef = 2;
150		/* fall through */
151
152	0	case ASN1_ITYPE_SEQUENCE:
153	0	i = ossl_asn1_enc_restore(&seqcontlen, out, pval, it);
154		/* An error occurred */
155	0	if (i < 0)
156	0	return 0;
157		/* We have a valid cached encoding... */
158	0	if (i > 0)
159	0	return seqcontlen;
160		/* Otherwise carry on */
161	0	seqcontlen = 0;
162		/* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
163	0	if (tag == -1) {
164	0	tag = V_ASN1_SEQUENCE;
165		/* Retain any other flags in aclass */
166	0	aclass = (aclass & ~ASN1_TFLG_TAG_CLASS)
167	0	\| V_ASN1_UNIVERSAL;
168	0	}
169	0	if (asn1_cb && !asn1_cb(ASN1_OP_I2D_PRE, pval, it, NULL))
170	0	return 0;
171		/* First work out sequence content length */
172	0	for (i = 0, tt = it->templates; i < it->tcount; tt++, i++) {
173	0	const ASN1_TEMPLATE *seqtt;
174	0	const ASN1_VALUE **pseqval;
175	0	int tmplen;
176	0	seqtt = ossl_asn1_do_adb(*pval, tt, 1);
177	0	if (!seqtt)
178	0	return 0;
179	0	pseqval = ossl_asn1_get_const_field_ptr(pval, seqtt);
180	0	tmplen = asn1_template_ex_i2d(pseqval, NULL, seqtt, -1, aclass);
181	0	if (tmplen == -1 \|\| (tmplen > INT_MAX - seqcontlen))
182	0	return -1;
183	0	seqcontlen += tmplen;
184	0	}
185
186	0	seqlen = ASN1_object_size(ndef, seqcontlen, tag);
187	0	if (!out \|\| seqlen == -1)
188	0	return seqlen;
189		/* Output SEQUENCE header */
190	0	ASN1_put_object(out, ndef, seqcontlen, tag, aclass);
191	0	for (i = 0, tt = it->templates; i < it->tcount; tt++, i++) {
192	0	const ASN1_TEMPLATE *seqtt;
193	0	const ASN1_VALUE **pseqval;
194	0	seqtt = ossl_asn1_do_adb(*pval, tt, 1);
195	0	if (!seqtt)
196	0	return 0;
197	0	pseqval = ossl_asn1_get_const_field_ptr(pval, seqtt);
198		/* FIXME: check for errors in enhanced version */
199	0	asn1_template_ex_i2d(pseqval, out, seqtt, -1, aclass);
200	0	}
201	0	if (ndef == 2)
202	0	ASN1_put_eoc(out);
203	0	if (asn1_cb && !asn1_cb(ASN1_OP_I2D_POST, pval, it, NULL))
204	0	return 0;
205	0	return seqlen;
206
207	0	default:
208	0	return 0;
209	0	}
210	0	return 0;
211	0	}
212
213		static int asn1_template_ex_i2d(const ASN1_VALUE pval, unsigned char out,
214		const ASN1_TEMPLATE *tt, int tag, int iclass)
215	0	{
216	0	const int flags = tt->flags;
217	0	int i, ret, ttag, tclass, ndef, len;
218	0	const ASN1_VALUE *tval;
219
220		/*
221		* If field is embedded then val needs fixing so it is a pointer to
222		* a pointer to a field.
223		*/
224	0	if (flags & ASN1_TFLG_EMBED) {
225	0	tval = (ASN1_VALUE *)pval;
226	0	pval = &tval;
227	0	}
228		/*
229		* Work out tag and class to use: tagging may come either from the
230		* template or the arguments, not both because this would create
231		* ambiguity. Additionally the iclass argument may contain some
232		* additional flags which should be noted and passed down to other
233		* levels.
234		*/
235	0	if (flags & ASN1_TFLG_TAG_MASK) {
236		/* Error if argument and template tagging */
237	0	if (tag != -1)
238		/* FIXME: error code here */
239	0	return -1;
240		/* Get tagging from template */
241	0	ttag = tt->tag;
242	0	tclass = flags & ASN1_TFLG_TAG_CLASS;
243	0	} else if (tag != -1) {
244		/* No template tagging, get from arguments */
245	0	ttag = tag;
246	0	tclass = iclass & ASN1_TFLG_TAG_CLASS;
247	0	} else {
248	0	ttag = -1;
249	0	tclass = 0;
250	0	}
251		/*
252		* Remove any class mask from iflag.
253		*/
254	0	iclass &= ~ASN1_TFLG_TAG_CLASS;
255
256		/*
257		* At this point 'ttag' contains the outer tag to use, 'tclass' is the
258		* class and iclass is any flags passed to this function.
259		*/
260
261		/* if template and arguments require ndef, use it */
262	0	if ((flags & ASN1_TFLG_NDEF) && (iclass & ASN1_TFLG_NDEF))
263	0	ndef = 2;
264	0	else
265	0	ndef = 1;
266
267	0	if (flags & ASN1_TFLG_SK_MASK) {
268		/* SET OF, SEQUENCE OF */
269	0	STACK_OF(const_ASN1_VALUE) sk = (STACK_OF(const_ASN1_VALUE) )*pval;
270	0	int isset, sktag, skaclass;
271	0	int skcontlen, sklen;
272	0	const ASN1_VALUE *skitem;
273
274	0	if (*pval == NULL)
275	0	return 0;
276
277	0	if (flags & ASN1_TFLG_SET_OF) {
278	0	isset = 1;
279		/* 2 means we reorder */
280	0	if (flags & ASN1_TFLG_SEQUENCE_OF)
281	0	isset = 2;
282	0	} else
283	0	isset = 0;
284
285		/*
286		* Work out inner tag value: if EXPLICIT or no tagging use underlying
287		* type.
288		*/
289	0	if ((ttag != -1) && !(flags & ASN1_TFLG_EXPTAG)) {
290	0	sktag = ttag;
291	0	skaclass = tclass;
292	0	} else {
293	0	skaclass = V_ASN1_UNIVERSAL;
294	0	if (isset)
295	0	sktag = V_ASN1_SET;
296	0	else
297	0	sktag = V_ASN1_SEQUENCE;
298	0	}
299
300		/* Determine total length of items */
301	0	skcontlen = 0;
302	0	for (i = 0; i < sk_const_ASN1_VALUE_num(sk); i++) {
303	0	skitem = sk_const_ASN1_VALUE_value(sk, i);
304	0	len = ASN1_item_ex_i2d(&skitem, NULL, ASN1_ITEM_ptr(tt->item),
305	0	-1, iclass);
306	0	if (len == -1 \|\| (skcontlen > INT_MAX - len))
307	0	return -1;
308	0	if (len == 0 && (tt->flags & ASN1_TFLG_OPTIONAL) == 0) {
309	0	ERR_raise(ERR_LIB_ASN1, ASN1_R_ILLEGAL_ZERO_CONTENT);
310	0	return -1;
311	0	}
312	0	skcontlen += len;
313	0	}
314	0	sklen = ASN1_object_size(ndef, skcontlen, sktag);
315	0	if (sklen == -1)
316	0	return -1;
317		/* If EXPLICIT need length of surrounding tag */
318	0	if (flags & ASN1_TFLG_EXPTAG)
319	0	ret = ASN1_object_size(ndef, sklen, ttag);
320	0	else
321	0	ret = sklen;
322
323	0	if (!out \|\| ret == -1)
324	0	return ret;
325
326		/* Now encode this lot... */
327		/* EXPLICIT tag */
328	0	if (flags & ASN1_TFLG_EXPTAG)
329	0	ASN1_put_object(out, ndef, sklen, ttag, tclass);
330		/* SET or SEQUENCE and IMPLICIT tag */
331	0	ASN1_put_object(out, ndef, skcontlen, sktag, skaclass);
332		/* And the stuff itself */
333	0	asn1_set_seq_out(sk, out, skcontlen, ASN1_ITEM_ptr(tt->item),
334	0	isset, iclass);
335	0	if (ndef == 2) {
336	0	ASN1_put_eoc(out);
337	0	if (flags & ASN1_TFLG_EXPTAG)
338	0	ASN1_put_eoc(out);
339	0	}
340
341	0	return ret;
342	0	}
343
344	0	if (flags & ASN1_TFLG_EXPTAG) {
345		/* EXPLICIT tagging */
346		/* Find length of tagged item */
347	0	i = ASN1_item_ex_i2d(pval, NULL, ASN1_ITEM_ptr(tt->item), -1, iclass);
348	0	if (i == 0) {
349	0	if ((tt->flags & ASN1_TFLG_OPTIONAL) == 0) {
350	0	ERR_raise(ERR_LIB_ASN1, ASN1_R_ILLEGAL_ZERO_CONTENT);
351	0	return -1;
352	0	}
353	0	return 0;
354	0	}
355		/* Find length of EXPLICIT tag */
356	0	ret = ASN1_object_size(ndef, i, ttag);
357	0	if (out && ret != -1) {
358		/* Output tag and item */
359	0	ASN1_put_object(out, ndef, i, ttag, tclass);
360	0	ASN1_item_ex_i2d(pval, out, ASN1_ITEM_ptr(tt->item), -1, iclass);
361	0	if (ndef == 2)
362	0	ASN1_put_eoc(out);
363	0	}
364	0	return ret;
365	0	}
366
367		/* Either normal or IMPLICIT tagging: combine class and flags */
368	0	len = ASN1_item_ex_i2d(pval, out, ASN1_ITEM_ptr(tt->item),
369	0	ttag, tclass \| iclass);
370	0	if (len == 0 && (tt->flags & ASN1_TFLG_OPTIONAL) == 0) {
371	0	ERR_raise(ERR_LIB_ASN1, ASN1_R_ILLEGAL_ZERO_CONTENT);
372	0	return -1;
373	0	}
374	0	return len;
375	0	}
376
377		/* Temporary structure used to hold DER encoding of items for SET OF */
378
379		typedef struct {
380		unsigned char *data;
381		int length;
382		const ASN1_VALUE *field;
383		} DER_ENC;
384
385		static int der_cmp(const void a, const void b)
386	0	{
387	0	const DER_ENC d1 = a, d2 = b;
388	0	int cmplen, i;
389	0	cmplen = (d1->length < d2->length) ? d1->length : d2->length;
390	0	i = memcmp(d1->data, d2->data, cmplen);
391	0	if (i)
392	0	return i;
393	0	return d1->length - d2->length;
394	0	}
395
396		/* Output the content octets of SET OF or SEQUENCE OF */
397
398		static int asn1_set_seq_out(STACK_OF(const_ASN1_VALUE) *sk,
399		unsigned char **out,
400		int skcontlen, const ASN1_ITEM *item,
401		int do_sort, int iclass)
402	0	{
403	0	int i, ret = 0;
404	0	const ASN1_VALUE *skitem;
405	0	unsigned char tmpdat = NULL, p = NULL;
406	0	DER_ENC derlst = NULL, tder;
407
408	0	if (do_sort) {
409		/* Don't need to sort less than 2 items */
410	0	if (sk_const_ASN1_VALUE_num(sk) < 2)
411	0	do_sort = 0;
412	0	else {
413	0	derlst = OPENSSL_malloc(sk_const_ASN1_VALUE_num(sk)
414	0	* sizeof(*derlst));
415	0	if (derlst == NULL)
416	0	return 0;
417	0	tmpdat = OPENSSL_malloc(skcontlen);
418	0	if (tmpdat == NULL)
419	0	goto err;
420	0	}
421	0	}
422		/* If not sorting just output each item */
423	0	if (!do_sort) {
424	0	for (i = 0; i < sk_const_ASN1_VALUE_num(sk); i++) {
425	0	skitem = sk_const_ASN1_VALUE_value(sk, i);
426	0	ASN1_item_ex_i2d(&skitem, out, item, -1, iclass);
427	0	}
428	0	return 1;
429	0	}
430	0	p = tmpdat;
431
432		/* Doing sort: build up a list of each member's DER encoding */
433	0	for (i = 0, tder = derlst; i < sk_const_ASN1_VALUE_num(sk); i++, tder++) {
434	0	skitem = sk_const_ASN1_VALUE_value(sk, i);
435	0	tder->data = p;
436	0	tder->length = ASN1_item_ex_i2d(&skitem, &p, item, -1, iclass);
437	0	tder->field = skitem;
438	0	}
439
440		/* Now sort them */
441	0	qsort(derlst, sk_const_ASN1_VALUE_num(sk), sizeof(*derlst), der_cmp);
442		/* Output sorted DER encoding */
443	0	p = *out;
444	0	for (i = 0, tder = derlst; i < sk_const_ASN1_VALUE_num(sk); i++, tder++) {
445	0	memcpy(p, tder->data, tder->length);
446	0	p += tder->length;
447	0	}
448	0	*out = p;
449		/* If do_sort is 2 then reorder the STACK */
450	0	if (do_sort == 2) {
451	0	for (i = 0, tder = derlst; i < sk_const_ASN1_VALUE_num(sk); i++, tder++)
452	0	(void)sk_const_ASN1_VALUE_set(sk, i, tder->field);
453	0	}
454	0	ret = 1;
455	0	err:
456	0	OPENSSL_free(derlst);
457	0	OPENSSL_free(tmpdat);
458	0	return ret;
459	0	}
460
461		static int asn1_i2d_ex_primitive(const ASN1_VALUE pval, unsigned char out,
462		const ASN1_ITEM *it, int tag, int aclass)
463	0	{
464	0	int len;
465	0	int utype;
466	0	int usetag;
467	0	int ndef = 0;
468
469	0	utype = it->utype;
470
471		/*
472		* Get length of content octets and maybe find out the underlying type.
473		*/
474
475	0	len = asn1_ex_i2c(pval, NULL, &utype, it);
476
477		/*
478		* If SEQUENCE, SET or OTHER then header is included in pseudo content
479		* octets so don't include tag+length. We need to check here because the
480		* call to asn1_ex_i2c() could change utype.
481		*/
482	0	if ((utype == V_ASN1_SEQUENCE) \|\| (utype == V_ASN1_SET) \|\| (utype == V_ASN1_OTHER))
483	0	usetag = 0;
484	0	else
485	0	usetag = 1;
486
487		/* -1 means omit type */
488
489	0	if (len == -1)
490	0	return 0;
491
492		/* -2 return is special meaning use ndef */
493	0	if (len == -2) {
494	0	ndef = 2;
495	0	len = 0;
496	0	}
497
498		/* If not implicitly tagged get tag from underlying type */
499	0	if (tag == -1)
500	0	tag = utype;
501
502		/* Output tag+length followed by content octets */
503	0	if (out) {
504	0	if (usetag)
505	0	ASN1_put_object(out, ndef, len, tag, aclass);
506	0	asn1_ex_i2c(pval, *out, &utype, it);
507	0	if (ndef)
508	0	ASN1_put_eoc(out);
509	0	else
510	0	*out += len;
511	0	}
512
513	0	if (usetag)
514	0	return ASN1_object_size(ndef, len, tag);
515	0	return len;
516	0	}
517
518		/* Produce content octets from a structure */
519
520		static int asn1_ex_i2c(const ASN1_VALUE *pval, unsigned char cout, int *putype,
521		const ASN1_ITEM *it)
522	0	{
523	0	ASN1_BOOLEAN *tbool = NULL;
524	0	ASN1_STRING *strtmp;
525	0	ASN1_OBJECT *otmp;
526	0	int utype;
527	0	const unsigned char *cont;
528	0	unsigned char c;
529	0	int len;
530	0	const ASN1_PRIMITIVE_FUNCS *pf;
531	0	pf = it->funcs;
532	0	if (pf && pf->prim_i2c)
533	0	return pf->prim_i2c(pval, cout, putype, it);
534
535		/* Should type be omitted? */
536	0	if ((it->itype != ASN1_ITYPE_PRIMITIVE)
537	0	\|\| (it->utype != V_ASN1_BOOLEAN)) {
538	0	if (*pval == NULL)
539	0	return -1;
540	0	}
541
542	0	if (it->itype == ASN1_ITYPE_MSTRING) {
543		/* If MSTRING type set the underlying type */
544	0	strtmp = (ASN1_STRING )pval;
545	0	utype = strtmp->type;
546	0	*putype = utype;
547	0	} else if (it->utype == V_ASN1_ANY) {
548		/* If ANY set type and pointer to value */
549	0	ASN1_TYPE *typ;
550	0	typ = (ASN1_TYPE )pval;
551	0	utype = typ->type;
552	0	*putype = utype;
553	0	pval = (const ASN1_VALUE *)&typ->value.asn1_value; / actually is const */
554	0	} else
555	0	utype = *putype;
556
557	0	switch (utype) {
558	0	case V_ASN1_OBJECT:
559	0	otmp = (ASN1_OBJECT )pval;
560	0	cont = otmp->data;
561	0	len = otmp->length;
562	0	if (cont == NULL \|\| len == 0)
563	0	return -1;
564	0	break;
565
566	0	case V_ASN1_UNDEF:
567	0	return -2;
568
569	0	case V_ASN1_NULL:
570	0	cont = NULL;
571	0	len = 0;
572	0	break;
573
574	0	case V_ASN1_BOOLEAN:
575	0	tbool = (ASN1_BOOLEAN *)pval;
576	0	if (*tbool == -1)
577	0	return -1;
578	0	if (it->utype != V_ASN1_ANY) {
579		/*
580		* Default handling if value == size field then omit
581		*/
582	0	if (*tbool && (it->size > 0))
583	0	return -1;
584	0	if (!*tbool && !it->size)
585	0	return -1;
586	0	}
587	0	c = (unsigned char)*tbool;
588	0	cont = &c;
589	0	len = 1;
590	0	break;
591
592	0	case V_ASN1_BIT_STRING:
593	0	return ossl_i2c_ASN1_BIT_STRING((ASN1_BIT_STRING )pval,
594	0	cout ? &cout : NULL);
595
596	0	case V_ASN1_INTEGER:
597	0	case V_ASN1_ENUMERATED:
598		/*
599		* These are all have the same content format as ASN1_INTEGER
600		*/
601	0	return ossl_i2c_ASN1_INTEGER((ASN1_INTEGER )pval, cout ? &cout : NULL);
602
603	0	case V_ASN1_OCTET_STRING:
604	0	case V_ASN1_NUMERICSTRING:
605	0	case V_ASN1_PRINTABLESTRING:
606	0	case V_ASN1_T61STRING:
607	0	case V_ASN1_VIDEOTEXSTRING:
608	0	case V_ASN1_IA5STRING:
609	0	case V_ASN1_UTCTIME:
610	0	case V_ASN1_GENERALIZEDTIME:
611	0	case V_ASN1_GRAPHICSTRING:
612	0	case V_ASN1_VISIBLESTRING:
613	0	case V_ASN1_GENERALSTRING:
614	0	case V_ASN1_UNIVERSALSTRING:
615	0	case V_ASN1_BMPSTRING:
616	0	case V_ASN1_UTF8STRING:
617	0	case V_ASN1_SEQUENCE:
618	0	case V_ASN1_SET:
619	0	default:
620		/* All based on ASN1_STRING and handled the same */
621	0	strtmp = (ASN1_STRING )pval;
622		/* Special handling for NDEF */
623	0	if ((it->size == ASN1_TFLG_NDEF)
624	0	&& (strtmp->flags & ASN1_STRING_FLAG_NDEF)) {
625	0	if (cout) {
626	0	strtmp->data = cout;
627	0	strtmp->length = 0;
628	0	}
629		/* Special return code */
630	0	return -2;
631	0	}
632	0	cont = strtmp->data;
633	0	len = strtmp->length;
634
635	0	break;
636	0	}
637	0	if (cout && len)
638	0	memcpy(cout, cont, len);
639	0	return len;
640	0	}