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

Source
/*
 * Copyright 2000-2026 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;

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

    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 (!ossl_asn1_call_aux_cb(aux, 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 (!ossl_asn1_call_aux_cb(aux, 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 (!ossl_asn1_call_aux_cb(aux, 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 (!ossl_asn1_call_aux_cb(aux, 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((const 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: 2026-07-16 06:59

Line	Count	Source
1		/*
2		* Copyright 2000-2026 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
89	0	if ((it->itype != ASN1_ITYPE_PRIMITIVE) && *pval == NULL)
90	0	return 0;
91
92	0	switch (it->itype) {
93
94	0	case ASN1_ITYPE_PRIMITIVE:
95	0	if (it->templates)
96	0	return asn1_template_ex_i2d(pval, out, it->templates,
97	0	tag, aclass);
98	0	return asn1_i2d_ex_primitive(pval, out, it, tag, aclass);
99
100	0	case ASN1_ITYPE_MSTRING:
101		/*
102		* It never makes sense for multi-strings to have implicit tagging, so
103		* if tag != -1, then this looks like an error in the template.
104		*/
105	0	if (tag != -1) {
106	0	ERR_raise(ERR_LIB_ASN1, ASN1_R_BAD_TEMPLATE);
107	0	return -1;
108	0	}
109	0	return asn1_i2d_ex_primitive(pval, out, it, -1, aclass);
110
111	0	case ASN1_ITYPE_CHOICE:
112		/*
113		* It never makes sense for CHOICE types to have implicit tagging, so
114		* if tag != -1, then this looks like an error in the template.
115		*/
116	0	if (tag != -1) {
117	0	ERR_raise(ERR_LIB_ASN1, ASN1_R_BAD_TEMPLATE);
118	0	return -1;
119	0	}
120	0	if (!ossl_asn1_call_aux_cb(aux, ASN1_OP_I2D_PRE, pval, it, NULL))
121	0	return 0;
122	0	i = ossl_asn1_get_choice_selector_const(pval, it);
123	0	if ((i >= 0) && (i < it->tcount)) {
124	0	const ASN1_VALUE **pchval;
125	0	const ASN1_TEMPLATE *chtt;
126	0	chtt = it->templates + i;
127	0	pchval = ossl_asn1_get_const_field_ptr(pval, chtt);
128	0	return asn1_template_ex_i2d(pchval, out, chtt, -1, aclass);
129	0	}
130		/* Fixme: error condition if selector out of range */
131	0	if (!ossl_asn1_call_aux_cb(aux, ASN1_OP_I2D_POST, pval, it, NULL))
132	0	return 0;
133	0	break;
134
135	0	case ASN1_ITYPE_EXTERN:
136		/* If new style i2d it does all the work */
137	0	ef = it->funcs;
138	0	return ef->asn1_ex_i2d(pval, out, it, tag, aclass);
139
140	0	case ASN1_ITYPE_NDEF_SEQUENCE:
141		/* Use indefinite length constructed if requested */
142	0	if (aclass & ASN1_TFLG_NDEF)
143	0	ndef = 2;
144		/* fall through */
145
146	0	case ASN1_ITYPE_SEQUENCE:
147	0	i = ossl_asn1_enc_restore(&seqcontlen, out, pval, it);
148		/* An error occurred */
149	0	if (i < 0)
150	0	return 0;
151		/* We have a valid cached encoding... */
152	0	if (i > 0)
153	0	return seqcontlen;
154		/* Otherwise carry on */
155	0	seqcontlen = 0;
156		/* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
157	0	if (tag == -1) {
158	0	tag = V_ASN1_SEQUENCE;
159		/* Retain any other flags in aclass */
160	0	aclass = (aclass & ~ASN1_TFLG_TAG_CLASS)
161	0	\| V_ASN1_UNIVERSAL;
162	0	}
163	0	if (!ossl_asn1_call_aux_cb(aux, ASN1_OP_I2D_PRE, pval, it, NULL))
164	0	return 0;
165		/* First work out sequence content length */
166	0	for (i = 0, tt = it->templates; i < it->tcount; tt++, i++) {
167	0	const ASN1_TEMPLATE *seqtt;
168	0	const ASN1_VALUE **pseqval;
169	0	int tmplen;
170	0	seqtt = ossl_asn1_do_adb(*pval, tt, 1);
171	0	if (!seqtt)
172	0	return 0;
173	0	pseqval = ossl_asn1_get_const_field_ptr(pval, seqtt);
174	0	tmplen = asn1_template_ex_i2d(pseqval, NULL, seqtt, -1, aclass);
175	0	if (tmplen == -1 \|\| (tmplen > INT_MAX - seqcontlen))
176	0	return -1;
177	0	seqcontlen += tmplen;
178	0	}
179
180	0	seqlen = ASN1_object_size(ndef, seqcontlen, tag);
181	0	if (!out \|\| seqlen == -1)
182	0	return seqlen;
183		/* Output SEQUENCE header */
184	0	ASN1_put_object(out, ndef, seqcontlen, tag, aclass);
185	0	for (i = 0, tt = it->templates; i < it->tcount; tt++, i++) {
186	0	const ASN1_TEMPLATE *seqtt;
187	0	const ASN1_VALUE **pseqval;
188	0	seqtt = ossl_asn1_do_adb(*pval, tt, 1);
189	0	if (!seqtt)
190	0	return 0;
191	0	pseqval = ossl_asn1_get_const_field_ptr(pval, seqtt);
192		/* FIXME: check for errors in enhanced version */
193	0	asn1_template_ex_i2d(pseqval, out, seqtt, -1, aclass);
194	0	}
195	0	if (ndef == 2)
196	0	ASN1_put_eoc(out);
197	0	if (!ossl_asn1_call_aux_cb(aux, ASN1_OP_I2D_POST, pval, it, NULL))
198	0	return 0;
199	0	return seqlen;
200
201	0	default:
202	0	return 0;
203	0	}
204	0	return 0;
205	0	}
206
207		static int asn1_template_ex_i2d(const ASN1_VALUE pval, unsigned char out,
208		const ASN1_TEMPLATE *tt, int tag, int iclass)
209	0	{
210	0	const int flags = tt->flags;
211	0	int i, ret, ttag, tclass, ndef, len;
212	0	const ASN1_VALUE *tval;
213
214		/*
215		* If field is embedded then val needs fixing so it is a pointer to
216		* a pointer to a field.
217		*/
218	0	if (flags & ASN1_TFLG_EMBED) {
219	0	tval = (ASN1_VALUE *)pval;
220	0	pval = &tval;
221	0	}
222		/*
223		* Work out tag and class to use: tagging may come either from the
224		* template or the arguments, not both because this would create
225		* ambiguity. Additionally the iclass argument may contain some
226		* additional flags which should be noted and passed down to other
227		* levels.
228		*/
229	0	if (flags & ASN1_TFLG_TAG_MASK) {
230		/* Error if argument and template tagging */
231	0	if (tag != -1)
232		/* FIXME: error code here */
233	0	return -1;
234		/* Get tagging from template */
235	0	ttag = tt->tag;
236	0	tclass = flags & ASN1_TFLG_TAG_CLASS;
237	0	} else if (tag != -1) {
238		/* No template tagging, get from arguments */
239	0	ttag = tag;
240	0	tclass = iclass & ASN1_TFLG_TAG_CLASS;
241	0	} else {
242	0	ttag = -1;
243	0	tclass = 0;
244	0	}
245		/*
246		* Remove any class mask from iflag.
247		*/
248	0	iclass &= ~ASN1_TFLG_TAG_CLASS;
249
250		/*
251		* At this point 'ttag' contains the outer tag to use, 'tclass' is the
252		* class and iclass is any flags passed to this function.
253		*/
254
255		/* if template and arguments require ndef, use it */
256	0	if ((flags & ASN1_TFLG_NDEF) && (iclass & ASN1_TFLG_NDEF))
257	0	ndef = 2;
258	0	else
259	0	ndef = 1;
260
261	0	if (flags & ASN1_TFLG_SK_MASK) {
262		/* SET OF, SEQUENCE OF */
263	0	STACK_OF(const_ASN1_VALUE) sk = (STACK_OF(const_ASN1_VALUE) )*pval;
264	0	int isset, sktag, skaclass;
265	0	int skcontlen, sklen;
266	0	const ASN1_VALUE *skitem;
267
268	0	if (*pval == NULL)
269	0	return 0;
270
271	0	if (flags & ASN1_TFLG_SET_OF) {
272	0	isset = 1;
273		/* 2 means we reorder */
274	0	if (flags & ASN1_TFLG_SEQUENCE_OF)
275	0	isset = 2;
276	0	} else
277	0	isset = 0;
278
279		/*
280		* Work out inner tag value: if EXPLICIT or no tagging use underlying
281		* type.
282		*/
283	0	if ((ttag != -1) && !(flags & ASN1_TFLG_EXPTAG)) {
284	0	sktag = ttag;
285	0	skaclass = tclass;
286	0	} else {
287	0	skaclass = V_ASN1_UNIVERSAL;
288	0	if (isset)
289	0	sktag = V_ASN1_SET;
290	0	else
291	0	sktag = V_ASN1_SEQUENCE;
292	0	}
293
294		/* Determine total length of items */
295	0	skcontlen = 0;
296	0	for (i = 0; i < sk_const_ASN1_VALUE_num(sk); i++) {
297	0	skitem = sk_const_ASN1_VALUE_value(sk, i);
298	0	len = ASN1_item_ex_i2d(&skitem, NULL, ASN1_ITEM_ptr(tt->item),
299	0	-1, iclass);
300	0	if (len == -1 \|\| (skcontlen > INT_MAX - len))
301	0	return -1;
302	0	if (len == 0 && (tt->flags & ASN1_TFLG_OPTIONAL) == 0) {
303	0	ERR_raise(ERR_LIB_ASN1, ASN1_R_ILLEGAL_ZERO_CONTENT);
304	0	return -1;
305	0	}
306	0	skcontlen += len;
307	0	}
308	0	sklen = ASN1_object_size(ndef, skcontlen, sktag);
309	0	if (sklen == -1)
310	0	return -1;
311		/* If EXPLICIT need length of surrounding tag */
312	0	if (flags & ASN1_TFLG_EXPTAG)
313	0	ret = ASN1_object_size(ndef, sklen, ttag);
314	0	else
315	0	ret = sklen;
316
317	0	if (!out \|\| ret == -1)
318	0	return ret;
319
320		/* Now encode this lot... */
321		/* EXPLICIT tag */
322	0	if (flags & ASN1_TFLG_EXPTAG)
323	0	ASN1_put_object(out, ndef, sklen, ttag, tclass);
324		/* SET or SEQUENCE and IMPLICIT tag */
325	0	ASN1_put_object(out, ndef, skcontlen, sktag, skaclass);
326		/* And the stuff itself */
327	0	asn1_set_seq_out(sk, out, skcontlen, ASN1_ITEM_ptr(tt->item),
328	0	isset, iclass);
329	0	if (ndef == 2) {
330	0	ASN1_put_eoc(out);
331	0	if (flags & ASN1_TFLG_EXPTAG)
332	0	ASN1_put_eoc(out);
333	0	}
334
335	0	return ret;
336	0	}
337
338	0	if (flags & ASN1_TFLG_EXPTAG) {
339		/* EXPLICIT tagging */
340		/* Find length of tagged item */
341	0	i = ASN1_item_ex_i2d(pval, NULL, ASN1_ITEM_ptr(tt->item), -1, iclass);
342	0	if (i == 0) {
343	0	if ((tt->flags & ASN1_TFLG_OPTIONAL) == 0) {
344	0	ERR_raise(ERR_LIB_ASN1, ASN1_R_ILLEGAL_ZERO_CONTENT);
345	0	return -1;
346	0	}
347	0	return 0;
348	0	}
349		/* Find length of EXPLICIT tag */
350	0	ret = ASN1_object_size(ndef, i, ttag);
351	0	if (out && ret != -1) {
352		/* Output tag and item */
353	0	ASN1_put_object(out, ndef, i, ttag, tclass);
354	0	ASN1_item_ex_i2d(pval, out, ASN1_ITEM_ptr(tt->item), -1, iclass);
355	0	if (ndef == 2)
356	0	ASN1_put_eoc(out);
357	0	}
358	0	return ret;
359	0	}
360
361		/* Either normal or IMPLICIT tagging: combine class and flags */
362	0	len = ASN1_item_ex_i2d(pval, out, ASN1_ITEM_ptr(tt->item),
363	0	ttag, tclass \| iclass);
364	0	if (len == 0 && (tt->flags & ASN1_TFLG_OPTIONAL) == 0) {
365	0	ERR_raise(ERR_LIB_ASN1, ASN1_R_ILLEGAL_ZERO_CONTENT);
366	0	return -1;
367	0	}
368	0	return len;
369	0	}
370
371		/* Temporary structure used to hold DER encoding of items for SET OF */
372
373		typedef struct {
374		unsigned char *data;
375		int length;
376		const ASN1_VALUE *field;
377		} DER_ENC;
378
379		static int der_cmp(const void a, const void b)
380	0	{
381	0	const DER_ENC d1 = a, d2 = b;
382	0	int cmplen, i;
383	0	cmplen = (d1->length < d2->length) ? d1->length : d2->length;
384	0	i = memcmp(d1->data, d2->data, cmplen);
385	0	if (i)
386	0	return i;
387	0	return d1->length - d2->length;
388	0	}
389
390		/* Output the content octets of SET OF or SEQUENCE OF */
391
392		static int asn1_set_seq_out(STACK_OF(const_ASN1_VALUE) *sk,
393		unsigned char **out,
394		int skcontlen, const ASN1_ITEM *item,
395		int do_sort, int iclass)
396	0	{
397	0	int i, ret = 0;
398	0	const ASN1_VALUE *skitem;
399	0	unsigned char tmpdat = NULL, p = NULL;
400	0	DER_ENC derlst = NULL, tder;
401
402	0	if (do_sort) {
403		/* Don't need to sort less than 2 items */
404	0	if (sk_const_ASN1_VALUE_num(sk) < 2)
405	0	do_sort = 0;
406	0	else {
407	0	derlst = OPENSSL_malloc(sk_const_ASN1_VALUE_num(sk)
408	0	* sizeof(*derlst));
409	0	if (derlst == NULL)
410	0	return 0;
411	0	tmpdat = OPENSSL_malloc(skcontlen);
412	0	if (tmpdat == NULL)
413	0	goto err;
414	0	}
415	0	}
416		/* If not sorting just output each item */
417	0	if (!do_sort) {
418	0	for (i = 0; i < sk_const_ASN1_VALUE_num(sk); i++) {
419	0	skitem = sk_const_ASN1_VALUE_value(sk, i);
420	0	ASN1_item_ex_i2d(&skitem, out, item, -1, iclass);
421	0	}
422	0	return 1;
423	0	}
424	0	p = tmpdat;
425
426		/* Doing sort: build up a list of each member's DER encoding */
427	0	for (i = 0, tder = derlst; i < sk_const_ASN1_VALUE_num(sk); i++, tder++) {
428	0	skitem = sk_const_ASN1_VALUE_value(sk, i);
429	0	tder->data = p;
430	0	tder->length = ASN1_item_ex_i2d(&skitem, &p, item, -1, iclass);
431	0	tder->field = skitem;
432	0	}
433
434		/* Now sort them */
435	0	qsort(derlst, sk_const_ASN1_VALUE_num(sk), sizeof(*derlst), der_cmp);
436		/* Output sorted DER encoding */
437	0	p = *out;
438	0	for (i = 0, tder = derlst; i < sk_const_ASN1_VALUE_num(sk); i++, tder++) {
439	0	memcpy(p, tder->data, tder->length);
440	0	p += tder->length;
441	0	}
442	0	*out = p;
443		/* If do_sort is 2 then reorder the STACK */
444	0	if (do_sort == 2) {
445	0	for (i = 0, tder = derlst; i < sk_const_ASN1_VALUE_num(sk); i++, tder++)
446	0	(void)sk_const_ASN1_VALUE_set(sk, i, tder->field);
447	0	}
448	0	ret = 1;
449	0	err:
450	0	OPENSSL_free(derlst);
451	0	OPENSSL_free(tmpdat);
452	0	return ret;
453	0	}
454
455		static int asn1_i2d_ex_primitive(const ASN1_VALUE pval, unsigned char out,
456		const ASN1_ITEM *it, int tag, int aclass)
457	0	{
458	0	int len;
459	0	int utype;
460	0	int usetag;
461	0	int ndef = 0;
462
463	0	utype = it->utype;
464
465		/*
466		* Get length of content octets and maybe find out the underlying type.
467		*/
468
469	0	len = asn1_ex_i2c(pval, NULL, &utype, it);
470
471		/*
472		* If SEQUENCE, SET or OTHER then header is included in pseudo content
473		* octets so don't include tag+length. We need to check here because the
474		* call to asn1_ex_i2c() could change utype.
475		*/
476	0	if ((utype == V_ASN1_SEQUENCE) \|\| (utype == V_ASN1_SET) \|\| (utype == V_ASN1_OTHER))
477	0	usetag = 0;
478	0	else
479	0	usetag = 1;
480
481		/* -1 means omit type */
482
483	0	if (len == -1)
484	0	return 0;
485
486		/* -2 return is special meaning use ndef */
487	0	if (len == -2) {
488	0	ndef = 2;
489	0	len = 0;
490	0	}
491
492		/* If not implicitly tagged get tag from underlying type */
493	0	if (tag == -1)
494	0	tag = utype;
495
496		/* Output tag+length followed by content octets */
497	0	if (out) {
498	0	if (usetag)
499	0	ASN1_put_object(out, ndef, len, tag, aclass);
500	0	asn1_ex_i2c(pval, *out, &utype, it);
501	0	if (ndef)
502	0	ASN1_put_eoc(out);
503	0	else
504	0	*out += len;
505	0	}
506
507	0	if (usetag)
508	0	return ASN1_object_size(ndef, len, tag);
509	0	return len;
510	0	}
511
512		/* Produce content octets from a structure */
513
514		static int asn1_ex_i2c(const ASN1_VALUE *pval, unsigned char cout, int *putype,
515		const ASN1_ITEM *it)
516	0	{
517	0	ASN1_BOOLEAN *tbool = NULL;
518	0	ASN1_STRING *strtmp;
519	0	ASN1_OBJECT *otmp;
520	0	int utype;
521	0	const unsigned char *cont;
522	0	unsigned char c;
523	0	int len;
524	0	const ASN1_PRIMITIVE_FUNCS *pf;
525	0	pf = it->funcs;
526	0	if (pf && pf->prim_i2c)
527	0	return pf->prim_i2c(pval, cout, putype, it);
528
529		/* Should type be omitted? */
530	0	if ((it->itype != ASN1_ITYPE_PRIMITIVE)
531	0	\|\| (it->utype != V_ASN1_BOOLEAN)) {
532	0	if (*pval == NULL)
533	0	return -1;
534	0	}
535
536	0	if (it->itype == ASN1_ITYPE_MSTRING) {
537		/* If MSTRING type set the underlying type */
538	0	strtmp = (ASN1_STRING )pval;
539	0	utype = strtmp->type;
540	0	*putype = utype;
541	0	} else if (it->utype == V_ASN1_ANY) {
542		/* If ANY set type and pointer to value */
543	0	ASN1_TYPE *typ;
544	0	typ = (ASN1_TYPE )pval;
545	0	utype = typ->type;
546	0	*putype = utype;
547	0	pval = (const ASN1_VALUE *)&typ->value.asn1_value; / actually is const */
548	0	} else
549	0	utype = *putype;
550
551	0	switch (utype) {
552	0	case V_ASN1_OBJECT:
553	0	otmp = (ASN1_OBJECT )pval;
554	0	cont = otmp->data;
555	0	len = otmp->length;
556	0	if (cont == NULL \|\| len == 0)
557	0	return -1;
558	0	break;
559
560	0	case V_ASN1_UNDEF:
561	0	return -2;
562
563	0	case V_ASN1_NULL:
564	0	cont = NULL;
565	0	len = 0;
566	0	break;
567
568	0	case V_ASN1_BOOLEAN:
569	0	tbool = (ASN1_BOOLEAN *)pval;
570	0	if (*tbool == -1)
571	0	return -1;
572	0	if (it->utype != V_ASN1_ANY) {
573		/*
574		* Default handling if value == size field then omit
575		*/
576	0	if (*tbool && (it->size > 0))
577	0	return -1;
578	0	if (!*tbool && !it->size)
579	0	return -1;
580	0	}
581	0	c = (unsigned char)*tbool;
582	0	cont = &c;
583	0	len = 1;
584	0	break;
585
586	0	case V_ASN1_BIT_STRING:
587	0	return ossl_i2c_ASN1_BIT_STRING((const ASN1_BIT_STRING )pval,
588	0	cout ? &cout : NULL);
589
590	0	case V_ASN1_INTEGER:
591	0	case V_ASN1_ENUMERATED:
592		/*
593		* These are all have the same content format as ASN1_INTEGER
594		*/
595	0	return ossl_i2c_ASN1_INTEGER((ASN1_INTEGER )pval, cout ? &cout : NULL);
596
597	0	case V_ASN1_OCTET_STRING:
598	0	case V_ASN1_NUMERICSTRING:
599	0	case V_ASN1_PRINTABLESTRING:
600	0	case V_ASN1_T61STRING:
601	0	case V_ASN1_VIDEOTEXSTRING:
602	0	case V_ASN1_IA5STRING:
603	0	case V_ASN1_UTCTIME:
604	0	case V_ASN1_GENERALIZEDTIME:
605	0	case V_ASN1_GRAPHICSTRING:
606	0	case V_ASN1_VISIBLESTRING:
607	0	case V_ASN1_GENERALSTRING:
608	0	case V_ASN1_UNIVERSALSTRING:
609	0	case V_ASN1_BMPSTRING:
610	0	case V_ASN1_UTF8STRING:
611	0	case V_ASN1_SEQUENCE:
612	0	case V_ASN1_SET:
613	0	default:
614		/* All based on ASN1_STRING and handled the same */
615	0	strtmp = (ASN1_STRING )pval;
616		/* Special handling for NDEF */
617	0	if ((it->size == ASN1_TFLG_NDEF)
618	0	&& (strtmp->flags & ASN1_STRING_FLAG_NDEF)) {
619	0	if (cout) {
620	0	strtmp->data = cout;
621	0	strtmp->length = 0;
622	0	}
623		/* Special return code */
624	0	return -2;
625	0	}
626	0	cont = strtmp->data;
627	0	len = strtmp->length;
628
629	0	break;
630	0	}
631	0	if (cout && len)
632	0	memcpy(cout, cont, len);
633	0	return len;
634	0	}