/* crypto/bio/bf_buff.c */

/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)

 * All rights reserved.

 *

 * This package is an SSL implementation written

 * by Eric Young (eay@cryptsoft.com).

 * 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 (tjh@cryptsoft.com).

 *

 * 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 (eay@cryptsoft.com)"

 *    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 (tjh@cryptsoft.com)"

 *

 * 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>

static int buffer_write(BIO *h, const char *buf, int num);

static int buffer_read(BIO *h, char *buf, int size);

static int buffer_puts(BIO *h, const char *str);

static int buffer_gets(BIO *h, char *str, int size);

static long buffer_ctrl(BIO *h, int cmd, long arg1, void *arg2);

static int buffer_new(BIO *h);

static int buffer_free(BIO *data);

static long buffer_callback_ctrl(BIO *h, int cmd, bio_info_cb *fp);

#define DEFAULT_BUFFER_SIZE     4096

static BIO_METHOD methods_buffer = {

    BIO_TYPE_BUFFER,

    "buffer",

    buffer_write,

    buffer_read,

    buffer_puts,

    buffer_gets,

    buffer_ctrl,

    buffer_new,

    buffer_free,

    buffer_callback_ctrl,

};

BIO_METHOD *BIO_f_buffer(void)

{

    return (&methods_buffer);

}

static int buffer_new(BIO *bi)

{

    BIO_F_BUFFER_CTX *ctx;

    ctx = (BIO_F_BUFFER_CTX *)OPENSSL_malloc(sizeof(BIO_F_BUFFER_CTX));

    if (ctx == NULL)

        return (0);

    ctx->ibuf = (char *)OPENSSL_malloc(DEFAULT_BUFFER_SIZE);

    if (ctx->ibuf == NULL) {

        OPENSSL_free(ctx);

        return (0);

    }

    ctx->obuf = (char *)OPENSSL_malloc(DEFAULT_BUFFER_SIZE);

    if (ctx->obuf == NULL) {

        OPENSSL_free(ctx->ibuf);

        OPENSSL_free(ctx);

        return (0);

    }

    ctx->ibuf_size = DEFAULT_BUFFER_SIZE;

    ctx->obuf_size = DEFAULT_BUFFER_SIZE;

    ctx->ibuf_len = 0;

    ctx->ibuf_off = 0;

    ctx->obuf_len = 0;

    ctx->obuf_off = 0;

    bi->init = 1;

    bi->ptr = (char *)ctx;

    bi->flags = 0;

    return (1);

}

static int buffer_free(BIO *a)

{

    BIO_F_BUFFER_CTX *b;

    if (a == NULL)

        return (0);

    b = (BIO_F_BUFFER_CTX *)a->ptr;

    if (b->ibuf != NULL)

        OPENSSL_free(b->ibuf);

    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 buffer_read(BIO *b, char *out, int outl)

{

    int i, num = 0;

    BIO_F_BUFFER_CTX *ctx;

    if (out == NULL)

        return (0);

    ctx = (BIO_F_BUFFER_CTX *)b->ptr;

    if ((ctx == NULL) || (b->next_bio == NULL))

        return (0);

    num = 0;

    BIO_clear_retry_flags(b);

 start:

    i = ctx->ibuf_len;

    /* If there is stuff left over, grab it */

    if (i != 0) {

        if (i > outl)

            i = outl;

        memcpy(out, &(ctx->ibuf[ctx->ibuf_off]), i);

        ctx->ibuf_off += i;

        ctx->ibuf_len -= i;

        num += i;

        if (outl == i)

            return (num);

        outl -= i;

        out += i;

    }

    /*

     * We may have done a partial read. try to do more. We have nothing in

     * the buffer. If we get an error and have read some data, just return it

     * and let them retry to get the error again. copy direct to parent

     * address space

     */

    if (outl > ctx->ibuf_size) {

        for (;;) {

            i = BIO_read(b->next_bio, out, outl);

            if (i <= 0) {

                BIO_copy_next_retry(b);

                if (i < 0)

                    return ((num > 0) ? num : i);

                if (i == 0)

                    return (num);

            }

            num += i;

            if (outl == i)

                return (num);

            out += i;

            outl -= i;

        }

    }

    /* else */

    /* we are going to be doing some buffering */

    i = BIO_read(b->next_bio, ctx->ibuf, ctx->ibuf_size);

    if (i <= 0) {

        BIO_copy_next_retry(b);

        if (i < 0)

            return ((num > 0) ? num : i);

        if (i == 0)

            return (num);

    }

    ctx->ibuf_off = 0;

    ctx->ibuf_len = i;

    /* Lets re-read using ourselves :-) */

    goto start;

}

static int buffer_write(BIO *b, const char *in, int inl)

{

    int i, num = 0;

    BIO_F_BUFFER_CTX *ctx;

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

        return (0);

    ctx = (BIO_F_BUFFER_CTX *)b->ptr;

    if ((ctx == NULL) || (b->next_bio == NULL))

        return (0);

    BIO_clear_retry_flags(b);

 start:

    i = ctx->obuf_size - (ctx->obuf_len + ctx->obuf_off);

    /* add to buffer and return */

    if (i >= inl) {

        memcpy(&(ctx->obuf[ctx->obuf_off + ctx->obuf_len]), in, inl);

        ctx->obuf_len += inl;

        return (num + inl);

    }

    /* else */

    /* stuff already in buffer, so add to it first, then flush */

    if (ctx->obuf_len != 0) {

        if (i > 0) {            /* lets fill it up if we can */

            memcpy(&(ctx->obuf[ctx->obuf_off + ctx->obuf_len]), in, i);

            in += i;

            inl -= i;

            num += i;

            ctx->obuf_len += i;

        }

        /* we now have a full buffer needing flushing */

        for (;;) {

            i = BIO_write(b->next_bio, &(ctx->obuf[ctx->obuf_off]),

                          ctx->obuf_len);

            if (i <= 0) {

                BIO_copy_next_retry(b);

                if (i < 0)

                    return ((num > 0) ? num : i);

                if (i == 0)

                    return (num);

            }

            ctx->obuf_off += i;

            ctx->obuf_len -= i;

            if (ctx->obuf_len == 0)

                break;

        }

    }

    /*

     * we only get here if the buffer has been flushed and we still have

     * stuff to write

     */

    ctx->obuf_off = 0;

    /* we now have inl bytes to write */

    while (inl >= ctx->obuf_size) {

        i = BIO_write(b->next_bio, in, inl);

        if (i <= 0) {

            BIO_copy_next_retry(b);

            if (i < 0)

                return ((num > 0) ? num : i);

            if (i == 0)

                return (num);

        }

        num += i;

        in += i;

        inl -= i;

        if (inl == 0)

            return (num);

    }

    /*

     * copy the rest into the buffer since we have only a small amount left

     */

    goto start;

}

static long buffer_ctrl(BIO *b, int cmd, long num, void *ptr)

{

    BIO *dbio;

    BIO_F_BUFFER_CTX *ctx;

    long ret = 1;

    char *p1, *p2;

    int r, i, *ip;

    int ibs, obs;

    ctx = (BIO_F_BUFFER_CTX *)b->ptr;

    switch (cmd) {

    case BIO_CTRL_RESET:

        ctx->ibuf_off = 0;

        ctx->ibuf_len = 0;

        ctx->obuf_off = 0;

        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_C_GET_BUFF_NUM_LINES:

        ret = 0;

        p1 = ctx->ibuf;

        for (i = 0; i < ctx->ibuf_len; i++) {

            if (p1[ctx->ibuf_off + i] == '\n')

                ret++;

        }

        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_CTRL_PENDING:

        ret = (long)ctx->ibuf_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_READ_DATA:

        if (num > ctx->ibuf_size) {

            p1 = OPENSSL_malloc((int)num);

            if (p1 == NULL)

                goto malloc_error;

            if (ctx->ibuf != NULL)

                OPENSSL_free(ctx->ibuf);

            ctx->ibuf = p1;

        }

        ctx->ibuf_off = 0;

        ctx->ibuf_len = (int)num;

        memcpy(ctx->ibuf, ptr, (int)num);

        ret = 1;

        break;

    case BIO_C_SET_BUFF_SIZE:

        if (ptr != NULL) {

            ip = (int *)ptr;

            if (*ip == 0) {

                ibs = (int)num;

                obs = ctx->obuf_size;

            } else {            /* if (*ip == 1) */

                ibs = ctx->ibuf_size;

                obs = (int)num;

            }

        } else {

            ibs = (int)num;

            obs = (int)num;

        }

        p1 = ctx->ibuf;

        p2 = ctx->obuf;

        if ((ibs > DEFAULT_BUFFER_SIZE) && (ibs != ctx->ibuf_size)) {

            p1 = (char *)OPENSSL_malloc((int)num);

            if (p1 == NULL)

                goto malloc_error;

        }

        if ((obs > DEFAULT_BUFFER_SIZE) && (obs != ctx->obuf_size)) {

            p2 = (char *)OPENSSL_malloc((int)num);

            if (p2 == NULL) {

                if (p1 != ctx->ibuf)

                    OPENSSL_free(p1);

                goto malloc_error;

            }

        }

        if (ctx->ibuf != p1) {

            OPENSSL_free(ctx->ibuf);

            ctx->ibuf = p1;

            ctx->ibuf_off = 0;

            ctx->ibuf_len = 0;

            ctx->ibuf_size = ibs;

        }

        if (ctx->obuf != p2) {

            OPENSSL_free(ctx->obuf);

            ctx->obuf = p2;

            ctx->obuf_off = 0;

            ctx->obuf_len = 0;

            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_off]), ctx->obuf_len);

#if 0

                fprintf(stderr, "FLUSH [%3d] %3d -> %3d\n", ctx->obuf_off,

                        ctx->obuf_len, r);

#endif

                BIO_copy_next_retry(b);

                if (r <= 0)

                    return ((long)r);

                ctx->obuf_off += r;

                ctx->obuf_len -= r;

            } else {

                ctx->obuf_len = 0;

                ctx->obuf_off = 0;

                ret = 1;

                break;

            }

        }

        ret = BIO_ctrl(b->next_bio, cmd, num, ptr);

        break;

    case BIO_CTRL_DUP:

        dbio = (BIO *)ptr;

        if (!BIO_set_read_buffer_size(dbio, ctx->ibuf_size) ||

            !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_BUFFER_CTRL, ERR_R_MALLOC_FAILURE);

    return (0);

}

static long buffer_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 buffer_gets(BIO *b, char *buf, int size)

{

    BIO_F_BUFFER_CTX *ctx;

    int num = 0, i, flag;

    char *p;

    ctx = (BIO_F_BUFFER_CTX *)b->ptr;

    size--;                     /* reserve space for a '\0' */

    BIO_clear_retry_flags(b);

    for (;;) {

        if (ctx->ibuf_len > 0) {

            p = &(ctx->ibuf[ctx->ibuf_off]);

            flag = 0;

            for (i = 0; (i < ctx->ibuf_len) && (i < size); i++) {

                *(buf++) = p[i];

                if (p[i] == '\n') {

                    flag = 1;

                    i++;

                    break;

                }

            }

            num += i;

            size -= i;

            ctx->ibuf_len -= i;

            ctx->ibuf_off += i;

            if (flag || size == 0) {

                *buf = '\0';

                return (num);

            }

        } else {                /* read another chunk */

            i = BIO_read(b->next_bio, ctx->ibuf, ctx->ibuf_size);

            if (i <= 0) {

                BIO_copy_next_retry(b);

                *buf = '\0';

                if (i < 0)

                    return ((num > 0) ? num : i);

                if (i == 0)

                    return (num);

            }

            ctx->ibuf_len = i;

            ctx->ibuf_off = 0;

        }

    }

}

static int buffer_puts(BIO *b, const char *str)

{

    return (buffer_write(b, str, strlen(str)));

}