ber_der/common/encode.c

	encode.c revision 2cbed7292737821015ab481353eb10e8346b2c05
/*
 * -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * The contents of this file are subject to the Netscape Public License
 * Version 1.0 (the "NPL"); you may not use this file except in
 * compliance with the NPL.  You may obtain a copy of the NPL at
 * http://www.mozilla.org/NPL/
 *
 * Software distributed under the NPL is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
 * for the specific language governing rights and limitations under the
 * NPL.
 *
 * The Initial Developer of this code under the NPL is Netscape
 * Communications Corporation.  Portions created by Netscape are
 * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
 * Reserved.
 */

/*
 * Copyright (c) 1990 Regents of the University of Michigan.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that this notice is preserved and that due credit is given
 * to the University of Michigan at Ann Arbor. The name of the University
 * may not be used to endorse or promote products derived from this
 * software without specific prior written permission. This software
 * is provided ``as is'' without express or implied warranty.
 */

/*
 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <sys/types.h>
#include <netinet/in.h>
#include <inttypes.h>

#include <ber_der.h>
#include "kmfber_int.h"

/* the following constants are used in kmfber_calc_lenlen */

#define LENMASK1    0xFF
#define LENMASK2    0xFFFF
#define LENMASK3    0xFFFFFF
#define LENMASK4    0xFFFFFFFF
#define _MASK       0x80

int
kmfber_calc_taglen(ber_tag_t tag)
{
    int     i;
    ber_int_t   mask;

    /* find the first non-all-zero byte in the tag */
    for (i = sizeof (ber_int_t) - 1; i > 0; i--) {
        mask = (LENMASK3 << (i * 8));
        /* not all zero */
        if (tag & mask)
            break;
    }

    return (i + 1);
}

static int
ber_put_tag(BerElement  *ber, ber_tag_t tag, int nosos)
{
    ber_int_t   taglen;
    ber_tag_t   ntag;

    taglen = kmfber_calc_taglen(tag);

    ntag = htonl(tag);

    return (kmfber_write(ber,
        ((char *) &ntag) + sizeof (ber_int_t) - taglen,
        taglen, nosos));
}

int
kmfber_calc_lenlen(ber_int_t len)
{
    /*
     * short len if it's less than 128 - one byte giving the len,
     * with bit 8 0.
     */

    if (len <= 0x7F)
        return (1);

    /*
     * long len otherwise - one byte with bit 8 set, giving the
     * length of the length, followed by the length itself.
     */

    if (len <= LENMASK1)
        return (2);
    if (len <= LENMASK2)
        return (3);
    if (len <= LENMASK3)
        return (4);

    return (5);
}

int
kmfber_put_len(BerElement *ber, ber_int_t len, int nosos)
{
    int     i;
    char        lenlen;
    ber_int_t   mask, netlen;

    /*
     * short len if it's less than 128 - one byte giving the len,
     * with bit 8 0.
     */
    if (len <= 127) {
        netlen = htonl(len);
        return (kmfber_write(ber,
            (char *)&netlen + sizeof (ber_int_t) - 1,
            1, nosos));
    }

    /*
     * long len otherwise - one byte with bit 8 set, giving the
     * length of the length, followed by the length itself.
     */

    /* find the first non-all-zero byte */
    for (i = sizeof (ber_int_t) - 1; i > 0; i--) {
        mask = (LENMASK1 << (i * 8));
        /* not all zero */
        if (len & mask)
            break;
    }
    lenlen = ++i;
    if (lenlen > 4)
        return (-1);
    lenlen |= 0x80;

    /* write the length of the length */
    if (kmfber_write(ber, &lenlen, 1, nosos) != 1)
        return (-1);

    /* write the length itself */
    netlen = htonl(len);
    if (kmfber_write(ber,
        (char *) &netlen + (sizeof (ber_int_t) - i), i, nosos) != i)
        return (-1);

    return (i + 1);
}

static int
ber_put_int_or_enum(BerElement *ber, ber_int_t num, ber_tag_t tag)
{
    int     i, sign;
    ber_int_t   len, lenlen, taglen, netnum, mask;

    sign = (num < 0);

    /*
     * high bit is set - look for first non-all-one byte
     * high bit is clear - look for first non-all-zero byte
     */
    for (i = sizeof (ber_int_t) - 1; i > 0; i--) {
        mask = (LENMASK1 << (i * 8));

        if (sign) {
            /* not all ones */
            if ((num & mask) != mask)
                break;
        } else {
            /* not all zero */
            if (num & mask)
                break;
        }
    }

    /*
     * we now have the "leading byte".  if the high bit on this
     * byte matches the sign bit, we need to "back up" a byte.
     */
    mask = (num & (_MASK << (i * 8)));
    if ((mask && !sign) || (sign && !mask))
        i++;

    len = i + 1;

    if ((taglen = ber_put_tag(ber, tag, 0)) == -1)
        return (-1);

    if ((lenlen = kmfber_put_len(ber, len, 0)) == -1)
        return (-1);
    i++;
    netnum = htonl(num);
    if (kmfber_write(ber,
        (char *) &netnum + (sizeof (ber_int_t) - i), i, 0) == i)
        /* length of tag + length + contents */
        return (taglen + lenlen + i);

    return (-1);
}

static int
kmfber_put_enum(BerElement *ber, ber_int_t num, ber_tag_t tag)
{
    if (tag == KMFBER_DEFAULT)
        tag = BER_ENUMERATED;

    return (ber_put_int_or_enum(ber, num, tag));
}

int
ber_put_int(BerElement *ber, ber_int_t num, ber_tag_t tag)
{
    if (tag == KMFBER_DEFAULT)
        tag = BER_INTEGER;

    return (ber_put_int_or_enum(ber, num, tag));
}

int
ber_put_oid(BerElement *ber, struct berval *oid, ber_tag_t tag)
{
    ber_int_t taglen, lenlen, rc, len;

    if (tag == KMFBER_DEFAULT)
        tag = 0x06;     /* TODO: Add new OID constant to header */

    if ((taglen = ber_put_tag(ber, tag, 0)) == -1)
        return (-1);

    len = (ber_int_t)oid->bv_len;
    if ((lenlen = kmfber_put_len(ber, len, 0)) == -1 ||
        kmfber_write(ber, oid->bv_val, oid->bv_len, 0) !=
        (ber_int_t)oid->bv_len) {
        rc = -1;
    } else {
        /* return length of tag + length + contents */
        rc = taglen + lenlen + oid->bv_len;
    }
    return (rc);
}

int
ber_put_big_int(BerElement *ber, ber_tag_t tag, char *data,
    ber_len_t len)
{
    ber_int_t taglen, lenlen, ilen, rc;
    char zero = 0x00;

    if (tag == KMFBER_DEFAULT)
        tag = BER_INTEGER;

    if ((taglen = ber_put_tag(ber, tag, 0)) == -1)
        return (-1);

    /* Add a leading 0 if the high order bit is set */
    if (data[0] & 0x80)
        len++;

    ilen = (ber_int_t)len;
    if ((lenlen = kmfber_put_len(ber, ilen, 0)) == -1)
        return (-1);

    /* add leading 0 if hi bit set */
    if ((data[0] & 0x80) && kmfber_write(ber, &zero, 1, 0) != 1)
        return (-1);

    /* Adjust the length of the write if hi-order bit is set */
    if (data[0] & 0x80)
        ilen = len - 1;
    if (kmfber_write(ber, data, ilen, 0) != (ber_int_t)ilen) {
        return (-1);
    } else {
        /* return length of tag + length + contents */
        rc = taglen + lenlen + len;
    }
    return (rc);
}

static int
kmfber_put_ostring(BerElement *ber, char *str, ber_len_t len,
    ber_tag_t tag)
{
    ber_int_t   taglen, lenlen, ilen, rc;
#ifdef STR_TRANSLATION
    int free_str;
#endif /* STR_TRANSLATION */

    if (tag == KMFBER_DEFAULT)
        tag = BER_OCTET_STRING;

    if ((taglen = ber_put_tag(ber, tag, 0)) == -1)
        return (-1);

#ifdef STR_TRANSLATION
    if (len > 0 && (ber->ber_options & KMFBER_OPT_TRANSLATE_STRINGS) != 0 &&
        ber->ber_encode_translate_proc != NULL) {
        if ((*(ber->ber_encode_translate_proc))(&str, &len, 0)
            != 0) {
            return (-1);
        }
        free_str = 1;
    } else {
        free_str = 0;
    }
#endif /* STR_TRANSLATION */

    /*
     *  Note:  below is a spot where we limit ber_write
     *  to signed long (instead of unsigned long)
     */
    ilen = (ber_int_t)len;
    if ((lenlen = kmfber_put_len(ber, ilen, 0)) == -1 ||
        kmfber_write(ber, str, len, 0) != (ber_int_t)len) {
        rc = -1;
    } else {
        /* return length of tag + length + contents */
        rc = taglen + lenlen + len;
    }

#ifdef STR_TRANSLATION
    if (free_str) {
        free(str);
    }
#endif /* STR_TRANSLATION */

    return (rc);
}

static int
kmfber_put_string(BerElement *ber, char *str, ber_tag_t tag)
{
    return (kmfber_put_ostring(ber, str, (ber_len_t)strlen(str), tag));
}

static int
kmfber_put_bitstring(BerElement *ber, char *str,
    ber_len_t blen /* in bits */, ber_tag_t tag)
{
    ber_int_t   taglen, lenlen, len;
    unsigned char   unusedbits;

    if (tag == KMFBER_DEFAULT)
        tag = BER_BIT_STRING;

    if ((taglen = ber_put_tag(ber, tag, 0)) == -1)
        return (-1);

    len = (blen + 7) / 8;
    unusedbits = (unsigned char) (len * 8 - blen);
    if ((lenlen = kmfber_put_len(ber, len + 1, 0)) == -1)
        return (-1);

    if (kmfber_write(ber, (char *)&unusedbits, 1, 0) != 1)
        return (-1);

    if (kmfber_write(ber, str, len, 0) != len)
        return (-1);

    /* return length of tag + length + unused bit count + contents */
    return (taglen + 1 + lenlen + len);
}

static int
kmfber_put_null(BerElement *ber, ber_tag_t tag)
{
    int taglen;

    if (tag == KMFBER_DEFAULT)
        tag = BER_NULL;

    if ((taglen = ber_put_tag(ber, tag, 0)) == -1)
        return (-1);

    if (kmfber_put_len(ber, 0, 0) != 1)
        return (-1);

    return (taglen + 1);
}

static int
kmfber_put_boolean(BerElement *ber, int boolval, ber_tag_t tag)
{
    int     taglen;
    unsigned char   trueval = 0xff;
    unsigned char   falseval = 0x00;

    if (tag == KMFBER_DEFAULT)
        tag = BER_BOOLEAN;

    if ((taglen = ber_put_tag(ber, tag, 0)) == -1)
        return (-1);

    if (kmfber_put_len(ber, 1, 0) != 1)
        return (-1);

    if (kmfber_write(ber, (char *)(boolval ? &trueval : &falseval), 1, 0)
        != 1)
        return (-1);

    return (taglen + 2);
}

#define FOUR_BYTE_LEN   5


/*
 * The idea here is roughly this: we maintain a stack of these Seqorset
 * structures. This is pushed when we see the beginning of a new set or
 * sequence. It is popped when we see the end of a set or sequence.
 * Since we don't want to malloc and free these structures all the time,
 * we pre-allocate a small set of them within the ber element structure.
 * thus we need to spot when we've overflowed this stack and fall back to
 * malloc'ing instead.
 */
static int
ber_start_seqorset(BerElement *ber, ber_tag_t tag)
{
    Seqorset    *new_sos;

    /* can we fit into the local stack ? */
    if (ber->ber_sos_stack_posn < SOS_STACK_SIZE) {
        /* yes */
        new_sos = &ber->ber_sos_stack[ber->ber_sos_stack_posn];
    } else {
        /* no */
        if ((new_sos = (Seqorset *)malloc(sizeof (Seqorset)))
            == NULLSEQORSET) {
            return (-1);
        }
    }
    ber->ber_sos_stack_posn++;

    if (ber->ber_sos == NULLSEQORSET)
        new_sos->sos_first = ber->ber_ptr;
    else
        new_sos->sos_first = ber->ber_sos->sos_ptr;

    /* Set aside room for a 4 byte length field */
    new_sos->sos_ptr = new_sos->sos_first + kmfber_calc_taglen(tag) +
        FOUR_BYTE_LEN;
    new_sos->sos_tag = tag;

    new_sos->sos_next = ber->ber_sos;
    new_sos->sos_clen = 0;

    ber->ber_sos = new_sos;
    if (ber->ber_sos->sos_ptr > ber->ber_end) {
        (void) realloc(ber, ber->ber_sos->sos_ptr - ber->ber_end);
    }
    return (0);
}

static int
kmfber_start_seq(BerElement *ber, ber_tag_t tag)
{
    if (tag == KMFBER_DEFAULT)
        tag = BER_CONSTRUCTED_SEQUENCE;

    return (ber_start_seqorset(ber, tag));
}

static int
kmfber_start_set(BerElement *ber, ber_tag_t tag)
{
    if (tag == KMFBER_DEFAULT)
        tag = BER_CONSTRUCTED_SET;

    return (ber_start_seqorset(ber, tag));
}

static int
ber_put_seqorset(BerElement *ber)
{
    ber_int_t   netlen, len, taglen, lenlen;
    unsigned char   ltag = 0x80 + FOUR_BYTE_LEN - 1;
    Seqorset    *next;
    Seqorset    **sos = &ber->ber_sos;

    /*
     * If this is the toplevel sequence or set, we need to actually
     * write the stuff out.  Otherwise, it's already been put in
     * the appropriate buffer and will be written when the toplevel
     * one is written.  In this case all we need to do is update the
     * length and tag.
     */

    len = (*sos)->sos_clen;
    netlen = (ber_len_t)htonl(len);

    if (ber->ber_options & KMFBER_OPT_USE_DER) {
        lenlen = kmfber_calc_lenlen(len);
    } else {
        lenlen = FOUR_BYTE_LEN;
    }

    if ((next = (*sos)->sos_next) == NULLSEQORSET) {
        /* write the tag */
        if ((taglen = ber_put_tag(ber, (*sos)->sos_tag, 1)) == -1)
            return (-1);

        if (ber->ber_options & KMFBER_OPT_USE_DER) {
            /* Write the length in the minimum # of octets */
            if (kmfber_put_len(ber, len, 1) == -1)
                return (-1);

            if (lenlen != FOUR_BYTE_LEN) {
                /*
                 * We set aside FOUR_BYTE_LEN bytes for
                 * the length field.  Move the data if
                 * we don't actually need that much
                 */
                (void) memmove((*sos)->sos_first + taglen +
                    lenlen, (*sos)->sos_first + taglen +
                    FOUR_BYTE_LEN, len);
            }
        } else {
            /* Fill FOUR_BYTE_LEN bytes for length field */
            /* one byte of length length */
            if (kmfber_write(ber, (char *)&ltag, 1, 1) != 1)
                return (-1);

            /* the length itself */
            if (kmfber_write(ber,
                (char *)&netlen + sizeof (ber_int_t)
                - (FOUR_BYTE_LEN - 1), FOUR_BYTE_LEN - 1, 1) !=
                FOUR_BYTE_LEN - 1)
                return (-1);
        }
        /* The ber_ptr is at the set/seq start - move it to the end */
        ber->ber_ptr += len;
    } else {
        ber_tag_t   ntag;

        /* the tag */
        taglen = kmfber_calc_taglen((*sos)->sos_tag);
        ntag = htonl((*sos)->sos_tag);
        (void) memmove((*sos)->sos_first, (char *)&ntag +
            sizeof (ber_int_t) - taglen, taglen);

        if (ber->ber_options & KMFBER_OPT_USE_DER) {
            ltag = (lenlen == 1) ? (unsigned char)len :
                (unsigned char) (0x80 + (lenlen - 1));
        }

        /* one byte of length length */
        (void) memmove((*sos)->sos_first + 1, &ltag, 1);

        if (ber->ber_options & KMFBER_OPT_USE_DER) {
            if (lenlen > 1) {
                /* Write the length itself */
                (void) memmove((*sos)->sos_first + 2,
                    (char *)&netlen + sizeof (ber_uint_t) -
                    (lenlen - 1),
                    lenlen - 1);
            }
            if (lenlen != FOUR_BYTE_LEN) {
                /*
                 * We set aside FOUR_BYTE_LEN bytes for
                 * the length field.  Move the data if
                 * we don't actually need that much
                 */
                (void) memmove((*sos)->sos_first + taglen +
                    lenlen, (*sos)->sos_first + taglen +
                    FOUR_BYTE_LEN, len);
            }
        } else {
            /* the length itself */
            (void) memmove((*sos)->sos_first + taglen + 1,
                (char *) &netlen + sizeof (ber_int_t) -
                (FOUR_BYTE_LEN - 1), FOUR_BYTE_LEN - 1);
        }

        next->sos_clen += (taglen + lenlen + len);
        next->sos_ptr += (taglen + lenlen + len);
    }

    /* we're done with this seqorset, so free it up */
    /* was this one from the local stack ? */
    if (ber->ber_sos_stack_posn > SOS_STACK_SIZE) {
        free((char *)(*sos));
    }
    ber->ber_sos_stack_posn--;
    *sos = next;

    return (taglen + lenlen + len);
}

/* VARARGS */
int
kmfber_printf(BerElement *ber, const char *fmt, ...)
{
    va_list     ap;
    char        *s, **ss;
    struct berval   **bv, *oid;
    int     rc, i, t;
    ber_int_t   len;

    va_start(ap, fmt);

#ifdef KMFBER_DEBUG
    if (lber_debug & 64) {
        char msg[80];
        sprintf(msg, "kmfber_printf fmt (%s)\n", fmt);
        ber_err_print(msg);
    }
#endif

    for (rc = 0; *fmt && rc != -1; fmt++) {
        switch (*fmt) {
        case 'b':   /* boolean */
            i = va_arg(ap, int);
            rc = kmfber_put_boolean(ber, i, ber->ber_tag);
            break;

        case 'i':   /* int */
            i = va_arg(ap, int);
            rc = ber_put_int(ber, (ber_int_t)i, ber->ber_tag);
            break;

        case 'D':   /* Object ID */
            if ((oid = va_arg(ap, struct berval *)) == NULL)
                break;
            rc = ber_put_oid(ber, oid, ber->ber_tag);
            break;
        case 'I':   /* int */
            s = va_arg(ap, char *);
            len = va_arg(ap, ber_int_t);
            rc = ber_put_big_int(ber, ber->ber_tag, s, len);
            break;

        case 'e':   /* enumeration */
            i = va_arg(ap, int);
            rc = kmfber_put_enum(ber, (ber_int_t)i, ber->ber_tag);
            break;

        case 'l':
            t = va_arg(ap, int);
            rc = kmfber_put_len(ber, t, 0);
            break;
        case 'n':   /* null */
            rc = kmfber_put_null(ber, ber->ber_tag);
            break;

        case 'o':   /* octet string (non-null terminated) */
            s = va_arg(ap, char *);
            len = va_arg(ap, int);
            rc = kmfber_put_ostring(ber, s, len, ber->ber_tag);
            break;

        case 's':   /* string */
            s = va_arg(ap, char *);
            rc = kmfber_put_string(ber, s, ber->ber_tag);
            break;

        case 'B':   /* bit string */
            s = va_arg(ap, char *);
            len = va_arg(ap, int);  /* in bits */
            rc = kmfber_put_bitstring(ber, s, len, ber->ber_tag);
            break;

        case 't':   /* tag for the next element */
            ber->ber_tag = va_arg(ap, ber_tag_t);
            ber->ber_usertag = 1;
            break;

        case 'T': /* Write an explicit tag, but don't change current */
            t = va_arg(ap, int);
            rc = ber_put_tag(ber, t, 0);
            break;

        case 'v':   /* vector of strings */
            if ((ss = va_arg(ap, char **)) == NULL)
                break;
            for (i = 0; ss[i] != NULL; i++) {
                if ((rc = kmfber_put_string(ber, ss[i],
                    ber->ber_tag)) == -1)
                    break;
            }
            break;

        case 'V':   /* sequences of strings + lengths */
            if ((bv = va_arg(ap, struct berval **)) == NULL)
                break;
            for (i = 0; bv[i] != NULL; i++) {
                if ((rc = kmfber_put_ostring(ber, bv[i]->bv_val,
                    bv[i]->bv_len, ber->ber_tag)) == -1)
                    break;
            }
            break;

        case '{':   /* begin sequence */
            rc = kmfber_start_seq(ber, ber->ber_tag);
            break;

        case '}':   /* end sequence */
            rc = ber_put_seqorset(ber);
            break;

        case '[':   /* begin set */
            rc = kmfber_start_set(ber, ber->ber_tag);
            break;

        case ']':   /* end set */
            rc = ber_put_seqorset(ber);
            break;

        default: {
#ifdef KMFBER_DEBUG
                char msg[80];
                sprintf(msg, "unknown fmt %c\n", *fmt);
                ber_err_print(msg);
#endif
                rc = -1;
                break;
            }
        }

        if (ber->ber_usertag == 0)
            ber->ber_tag = KMFBER_DEFAULT;
        else
            ber->ber_usertag = 0;
    }

    va_end(ap);

    return (rc);
}