bf_lbuf.c

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/* crypto/bio/bf_buff.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/bio.h>
#include <openssl/evp.h>

static int linebuffer_write(BIO *h, const char *buf,int num);
static int linebuffer_read(BIO *h, char *buf, int size);
static int linebuffer_puts(BIO *h, const char *str);
static int linebuffer_gets(BIO *h, char *str, int size);
static long linebuffer_ctrl(BIO *h, int cmd, long arg1, void *arg2);
static int linebuffer_new(BIO *h);
static int linebuffer_free(BIO *data);
static long linebuffer_callback_ctrl(BIO *h, int cmd, bio_info_cb *fp);

/* A 10k maximum should be enough for most purposes */
#define DEFAULT_LINEBUFFER_SIZE 1024*10

/* #define DEBUG */

static BIO_METHOD methods_linebuffer=
    {
    BIO_TYPE_LINEBUFFER,
    "linebuffer",
    linebuffer_write,
    linebuffer_read,
    linebuffer_puts,
    linebuffer_gets,
    linebuffer_ctrl,
    linebuffer_new,
    linebuffer_free,
    linebuffer_callback_ctrl,
    };

BIO_METHOD *BIO_f_linebuffer(void)
    {
    return(&methods_linebuffer);
    }

typedef struct bio_linebuffer_ctx_struct
    {
    char *obuf;     /* the output char array */
    int obuf_size;      /* how big is the output buffer */
    int obuf_len;       /* how many bytes are in it */
    } BIO_LINEBUFFER_CTX;

static int linebuffer_new(BIO *bi)
    {
    BIO_LINEBUFFER_CTX *ctx;

    ctx=(BIO_LINEBUFFER_CTX *)OPENSSL_malloc(sizeof(BIO_LINEBUFFER_CTX));
    if (ctx == NULL) return(0);
    ctx->obuf=(char *)OPENSSL_malloc(DEFAULT_LINEBUFFER_SIZE);
    if (ctx->obuf == NULL) { OPENSSL_free(ctx); return(0); }
    ctx->obuf_size=DEFAULT_LINEBUFFER_SIZE;
    ctx->obuf_len=0;

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

static int linebuffer_free(BIO *a)
    {
    BIO_LINEBUFFER_CTX *b;

    if (a == NULL) return(0);
    b=(BIO_LINEBUFFER_CTX *)a->ptr;
    if (b->obuf != NULL) OPENSSL_free(b->obuf);
    OPENSSL_free(a->ptr);
    a->ptr=NULL;
    a->init=0;
    a->flags=0;
    return(1);
    }
    
static int linebuffer_read(BIO *b, char *out, int outl)
    {
    int ret=0;
 
    if (out == NULL) return(0);
    if (b->next_bio == NULL) return(0);
    ret=BIO_read(b->next_bio,out,outl);
    BIO_clear_retry_flags(b);
    BIO_copy_next_retry(b);
    return(ret);
    }

static int linebuffer_write(BIO *b, const char *in, int inl)
    {
    int i,num=0,foundnl;
    BIO_LINEBUFFER_CTX *ctx;

    if ((in == NULL) || (inl <= 0)) return(0);
    ctx=(BIO_LINEBUFFER_CTX *)b->ptr;
    if ((ctx == NULL) || (b->next_bio == NULL)) return(0);

    BIO_clear_retry_flags(b);

    do
        {
        const char *p;

        for(p = in; p < in + inl && *p != '\n'; p++)
            ;
        if (*p == '\n')
            {
            p++;
            foundnl = 1;
            }
        else
            foundnl = 0;

        /* If a NL was found and we already have text in the save
           buffer, concatenate them and write */
        while ((foundnl || p - in > ctx->obuf_size - ctx->obuf_len)
            && ctx->obuf_len > 0)
            {
            int orig_olen = ctx->obuf_len;
            
            i = ctx->obuf_size - ctx->obuf_len;
            if (p - in > 0)
                {
                if (i >= p - in)
                    {
                    memcpy(&(ctx->obuf[ctx->obuf_len]),
                        in,p - in);
                    ctx->obuf_len += p - in;
                    inl -= p - in;
                    num += p - in;
                    in = p;
                    }
                else
                    {
                    memcpy(&(ctx->obuf[ctx->obuf_len]),
                        in,i);
                    ctx->obuf_len += i;
                    inl -= i;
                    in += i;
                    num += i;
                    }
                }

#if 0
BIO_write(b->next_bio, "<*<", 3);
#endif
            i=BIO_write(b->next_bio,
                ctx->obuf, ctx->obuf_len);
            if (i <= 0)
                {
                ctx->obuf_len = orig_olen;
                BIO_copy_next_retry(b);

#if 0
BIO_write(b->next_bio, ">*>", 3);
#endif
                if (i < 0) return((num > 0)?num:i);
                if (i == 0) return(num);
                }
#if 0
BIO_write(b->next_bio, ">*>", 3);
#endif
            if (i < ctx->obuf_len)
                memmove(ctx->obuf, ctx->obuf + i,
                    ctx->obuf_len - i);
            ctx->obuf_len-=i;
            }

        /* Now that the save buffer is emptied, let's write the input
           buffer if a NL was found and there is anything to write. */
        if ((foundnl || p - in > ctx->obuf_size) && p - in > 0)
            {
#if 0
BIO_write(b->next_bio, "<*<", 3);
#endif
            i=BIO_write(b->next_bio,in,p - in);
            if (i <= 0)
                {
                BIO_copy_next_retry(b);
#if 0
BIO_write(b->next_bio, ">*>", 3);
#endif
                if (i < 0) return((num > 0)?num:i);
                if (i == 0) return(num);
                }
#if 0
BIO_write(b->next_bio, ">*>", 3);
#endif
            num+=i;
            in+=i;
            inl-=i;
            }
        }
    while(foundnl && inl > 0);
    /* We've written as much as we can.  The rest of the input buffer, if
       any, is text that doesn't and with a NL and therefore needs to be
       saved for the next trip. */
    if (inl > 0)
        {
        memcpy(&(ctx->obuf[ctx->obuf_len]), in, inl);
        ctx->obuf_len += inl;
        num += inl;
        }
    return num;
    }

static long linebuffer_ctrl(BIO *b, int cmd, long num, void *ptr)
    {
    BIO *dbio;
    BIO_LINEBUFFER_CTX *ctx;
    long ret=1;
    char *p;
    int r;
    int obs;

    ctx=(BIO_LINEBUFFER_CTX *)b->ptr;

    switch (cmd)
        {
    case BIO_CTRL_RESET:
        ctx->obuf_len=0;
        if (b->next_bio == NULL) return(0);
        ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
        break;
    case BIO_CTRL_INFO:
        ret=(long)ctx->obuf_len;
        break;
    case BIO_CTRL_WPENDING:
        ret=(long)ctx->obuf_len;
        if (ret == 0)
            {
            if (b->next_bio == NULL) return(0);
            ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
            }
        break;
    case BIO_C_SET_BUFF_SIZE:
        obs=(int)num;
        p=ctx->obuf;
        if ((obs > DEFAULT_LINEBUFFER_SIZE) && (obs != ctx->obuf_size))
            {
            p=(char *)OPENSSL_malloc((int)num);
            if (p == NULL)
                goto malloc_error;
            }
        if (ctx->obuf != p)
            {
            if (ctx->obuf_len > obs)
                {
                ctx->obuf_len = obs;
                }
            memcpy(p, ctx->obuf, ctx->obuf_len);
            OPENSSL_free(ctx->obuf);
            ctx->obuf=p;
            ctx->obuf_size=obs;
            }
        break;
    case BIO_C_DO_STATE_MACHINE:
        if (b->next_bio == NULL) return(0);
        BIO_clear_retry_flags(b);
        ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
        BIO_copy_next_retry(b);
        break;

    case BIO_CTRL_FLUSH:
        if (b->next_bio == NULL) return(0);
        if (ctx->obuf_len <= 0)
            {
            ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
            break;
            }

        for (;;)
            {
            BIO_clear_retry_flags(b);
            if (ctx->obuf_len > 0)
                {
                r=BIO_write(b->next_bio,
                    ctx->obuf, ctx->obuf_len);
#if 0
fprintf(stderr,"FLUSH %3d -> %3d\n",ctx->obuf_len,r);
#endif
                BIO_copy_next_retry(b);
                if (r <= 0) return((long)r);
                if (r < ctx->obuf_len)
                    memmove(ctx->obuf, ctx->obuf + r,
                        ctx->obuf_len - r);
                ctx->obuf_len-=r;
                }
            else
                {
                ctx->obuf_len=0;
                ret=1;
                break;
                }
            }
        ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
        break;
    case BIO_CTRL_DUP:
        dbio=(BIO *)ptr;
        if (    !BIO_set_write_buffer_size(dbio,ctx->obuf_size))
            ret=0;
        break;
    default:
        if (b->next_bio == NULL) return(0);
        ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
        break;
        }
    return(ret);
malloc_error:
    BIOerr(BIO_F_LINEBUFFER_CTRL,ERR_R_MALLOC_FAILURE);
    return(0);
    }

static long linebuffer_callback_ctrl(BIO *b, int cmd, bio_info_cb *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);
    }

static int linebuffer_gets(BIO *b, char *buf, int size)
    {
    if (b->next_bio == NULL) return(0);
    return(BIO_gets(b->next_bio,buf,size));
    }

static int linebuffer_puts(BIO *b, const char *str)
    {
    return(linebuffer_write(b,str,strlen(str)));
    }