bio_ber.c

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/* crypto/evp/bio_ber.c */
/* Copyright (C) 1995-1998 Eric Young ([email protected])
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young ([email protected]).
 * The implementation was written so as to conform with Netscapes SSL.
 * 
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson ([email protected]).
 * 
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young ([email protected])"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from 
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson ([email protected])"
 * 
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * 
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

#include <stdio.h>
#include <errno.h>
#include "cryptlib.h"
#include <openssl/buffer.h>
#include <openssl/evp.h>

static int ber_write(BIO *h,char *buf,int num);
static int ber_read(BIO *h,char *buf,int size);
/*static int ber_puts(BIO *h,char *str); */
/*static int ber_gets(BIO *h,char *str,int size); */
static long ber_ctrl(BIO *h,int cmd,long arg1,char *arg2);
static int ber_new(BIO *h);
static int ber_free(BIO *data);
static long ber_callback_ctrl(BIO *h,int cmd,void *(*fp)());
#define BER_BUF_SIZE    (32)

/* This is used to hold the state of the BER objects being read. */
typedef struct ber_struct
    {
    int tag;
    int class;
    long length;
    int inf;
    int num_left;
    int depth;
    } BER_CTX;

typedef struct bio_ber_struct
    {
    int tag;
    int class;
    long length;
    int inf;

    /* most of the following are used when doing non-blocking IO */
    /* reading */
    long num_left;  /* number of bytes still to read/write in block */
    int depth;  /* used with indefinite encoding. */
    int finished;   /* No more read data */

    /* writting */ 
    char *w_addr;
    int w_offset;
    int w_left;

    int buf_len;
    int buf_off;
    unsigned char buf[BER_BUF_SIZE];
    } BIO_BER_CTX;

static BIO_METHOD methods_ber=
    {
    BIO_TYPE_CIPHER,"cipher",
    ber_write,
    ber_read,
    NULL, /* ber_puts, */
    NULL, /* ber_gets, */
    ber_ctrl,
    ber_new,
    ber_free,
    ber_callback_ctrl,
    };

BIO_METHOD *BIO_f_ber(void)
    {
    return(&methods_ber);
    }

static int ber_new(BIO *bi)
    {
    BIO_BER_CTX *ctx;

    ctx=(BIO_BER_CTX *)OPENSSL_malloc(sizeof(BIO_BER_CTX));
    if (ctx == NULL) return(0);

    memset((char *)ctx,0,sizeof(BIO_BER_CTX));

    bi->init=0;
    bi->ptr=(char *)ctx;
    bi->flags=0;
    return(1);
    }

static int ber_free(BIO *a)
    {
    BIO_BER_CTX *b;

    if (a == NULL) return(0);
    b=(BIO_BER_CTX *)a->ptr;
    OPENSSL_cleanse(a->ptr,sizeof(BIO_BER_CTX));
    OPENSSL_free(a->ptr);
    a->ptr=NULL;
    a->init=0;
    a->flags=0;
    return(1);
    }

int bio_ber_get_header(BIO *bio, BIO_BER_CTX *ctx)
    {
    char buf[64];
    int i,j,n;
    int ret;
    unsigned char *p;
    unsigned long length
    int tag;
    int class;
    long max;

    BIO_clear_retry_flags(b);

    /* Pack the buffer down if there is a hole at the front */
    if (ctx->buf_off != 0)
        {
        p=ctx->buf;
        j=ctx->buf_off;
        n=ctx->buf_len-j;
        for (i=0; i<n; i++)
            {
            p[0]=p[j];
            p++;
            }
        ctx->buf_len-j;
        ctx->buf_off=0;
        }

    /* If there is more room, read some more data */
    i=BER_BUF_SIZE-ctx->buf_len;
    if (i)
        {
        i=BIO_read(bio->next_bio,&(ctx->buf[ctx->buf_len]),i);
        if (i <= 0)
            {
            BIO_copy_next_retry(b);
            return(i);
            }
        else
            ctx->buf_len+=i;
        }

    max=ctx->buf_len;
    p=ctx->buf;
    ret=ASN1_get_object(&p,&length,&tag,&class,max);

    if (ret & 0x80)
        {
        if ((ctx->buf_len < BER_BUF_SIZE) &&
            (ERR_GET_REASON(ERR_peek_error()) == ASN1_R_TOO_LONG))
            {
            ERR_clear_error(); /* clear the error */
            BIO_set_retry_read(b);
            }
        return(-1);
        }

    /* We have no error, we have a header, so make use of it */

    if ((ctx->tag  >= 0) && (ctx->tag != tag))
        {
        BIOerr(BIO_F_BIO_BER_GET_HEADER,BIO_R_TAG_MISMATCH);
        sprintf(buf,"tag=%d, got %d",ctx->tag,tag);
        ERR_add_error_data(1,buf);
        return(-1);
        }
    if (ret & 0x01)
    if (ret & V_ASN1_CONSTRUCTED)
    }
    
static int ber_read(BIO *b, char *out, int outl)
    {
    int ret=0,i,n;
    BIO_BER_CTX *ctx;

    BIO_clear_retry_flags(b);

    if (out == NULL) return(0);
    ctx=(BIO_BER_CTX *)b->ptr;

    if ((ctx == NULL) || (b->next_bio == NULL)) return(0);

    if (ctx->finished) return(0);

again:
    /* First see if we are half way through reading a block */
    if (ctx->num_left > 0)
        {
        if (ctx->num_left < outl)
            n=ctx->num_left;
        else
            n=outl;
        i=BIO_read(b->next_bio,out,n);
        if (i <= 0)
            {
            BIO_copy_next_retry(b);
            return(i);
            }
        ctx->num_left-=i;
        outl-=i;
        ret+=i;
        if (ctx->num_left <= 0)
            {
            ctx->depth--;
            if (ctx->depth <= 0)
                ctx->finished=1;
            }
        if (outl <= 0)
            return(ret);
        else
            goto again;
        }
    else    /* we need to read another BER header */
        {
        }
    }

static int ber_write(BIO *b, char *in, int inl)
    {
    int ret=0,n,i;
    BIO_ENC_CTX *ctx;

    ctx=(BIO_ENC_CTX *)b->ptr;
    ret=inl;

    BIO_clear_retry_flags(b);
    n=ctx->buf_len-ctx->buf_off;
    while (n > 0)
        {
        i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n);
        if (i <= 0)
            {
            BIO_copy_next_retry(b);
            return(i);
            }
        ctx->buf_off+=i;
        n-=i;
        }
    /* at this point all pending data has been written */

    if ((in == NULL) || (inl <= 0)) return(0);

    ctx->buf_off=0;
    while (inl > 0)
        {
        n=(inl > ENC_BLOCK_SIZE)?ENC_BLOCK_SIZE:inl;
        EVP_CipherUpdate(&(ctx->cipher),
            (unsigned char *)ctx->buf,&ctx->buf_len,
            (unsigned char *)in,n);
        inl-=n;
        in+=n;

        ctx->buf_off=0;
        n=ctx->buf_len;
        while (n > 0)
            {
            i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n);
            if (i <= 0)
                {
                BIO_copy_next_retry(b);
                return(i);
                }
            n-=i;
            ctx->buf_off+=i;
            }
        ctx->buf_len=0;
        ctx->buf_off=0;
        }
    BIO_copy_next_retry(b);
    return(ret);
    }

static long ber_ctrl(BIO *b, int cmd, long num, char *ptr)
    {
    BIO *dbio;
    BIO_ENC_CTX *ctx,*dctx;
    long ret=1;
    int i;

    ctx=(BIO_ENC_CTX *)b->ptr;

    switch (cmd)
        {
    case BIO_CTRL_RESET:
        ctx->ok=1;
        ctx->finished=0;
        EVP_CipherInit_ex(&(ctx->cipher),NULL,NULL,NULL,NULL,
            ctx->cipher.berrypt);
        ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
        break;
    case BIO_CTRL_EOF:  /* More to read */
        if (ctx->cont <= 0)
            ret=1;
        else
            ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
        break;
    case BIO_CTRL_WPENDING:
        ret=ctx->buf_len-ctx->buf_off;
        if (ret <= 0)
            ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
        break;
    case BIO_CTRL_PENDING: /* More to read in buffer */
        ret=ctx->buf_len-ctx->buf_off;
        if (ret <= 0)
            ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
        break;
    case BIO_CTRL_FLUSH:
        /* do a final write */
again:
        while (ctx->buf_len != ctx->buf_off)
            {
            i=ber_write(b,NULL,0);
            if (i < 0)
                {
                ret=i;
                break;
                }
            }

        if (!ctx->finished)
            {
            ctx->finished=1;
            ctx->buf_off=0;
            ret=EVP_CipherFinal_ex(&(ctx->cipher),
                (unsigned char *)ctx->buf,
                &(ctx->buf_len));
            ctx->ok=(int)ret;
            if (ret <= 0) break;

            /* push out the bytes */
            goto again;
            }
        
        /* Finally flush the underlying BIO */
        ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
        break;
    case BIO_C_GET_CIPHER_STATUS:
        ret=(long)ctx->ok;
        break;
    case BIO_C_DO_STATE_MACHINE:
        BIO_clear_retry_flags(b);
        ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
        BIO_copy_next_retry(b);
        break;

    case BIO_CTRL_DUP:
        dbio=(BIO *)ptr;
        dctx=(BIO_ENC_CTX *)dbio->ptr;
        memcpy(&(dctx->cipher),&(ctx->cipher),sizeof(ctx->cipher));
        dbio->init=1;
        break;
    default:
        ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
        break;
        }
    return(ret);
    }

static long ber_callback_ctrl(BIO *b, int cmd, void *(*fp)())
    {
    long ret=1;

    if (b->next_bio == NULL) return(0);
    switch (cmd)
        {
    default:
        ret=BIO_callback_ctrl(b->next_bio,cmd,fp);
        break;
        }
    return(ret);
    }

/*
void BIO_set_cipher_ctx(b,c)
BIO *b;
EVP_CIPHER_ctx *c;
    {
    if (b == NULL) return;

    if ((b->callback != NULL) &&
        (b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,0L) <= 0))
        return;

    b->init=1;
    ctx=(BIO_ENC_CTX *)b->ptr;
    memcpy(ctx->cipher,c,sizeof(EVP_CIPHER_CTX));
    
    if (b->callback != NULL)
        b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,1L);
    }
*/

void BIO_set_cipher(BIO *b, EVP_CIPHER *c, unsigned char *k, unsigned char *i,
         int e)
    {
    BIO_ENC_CTX *ctx;

    if (b == NULL) return;

    if ((b->callback != NULL) &&
        (b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,0L) <= 0))
        return;

    b->init=1;
    ctx=(BIO_ENC_CTX *)b->ptr;
    EVP_CipherInit_ex(&(ctx->cipher),c,NULL,k,i,e);
    
    if (b->callback != NULL)
        b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,1L);
    }