openssl/ssl/bio_ssl.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 <stdlib.h>
#include <string.h>
#include <errno.h>
#include <openssl/crypto.h>
#include <openssl/bio.h>
#include <openssl/err.h>
#include "ssl_locl.h"

static int ssl_write(BIO *h, const char *buf, int num);
static int ssl_read(BIO *h, char *buf, int size);
static int ssl_puts(BIO *h, const char *str);
static long ssl_ctrl(BIO *h, int cmd, long arg1, void *arg2);
static int ssl_new(BIO *h);
static int ssl_free(BIO *data);
static long ssl_callback_ctrl(BIO *h, int cmd, bio_info_cb *fp);
typedef struct bio_ssl_st {
    SSL *ssl;                   /* The ssl handle :-) */
    /* re-negotiate every time the total number of bytes is this size */
    int num_renegotiates;
    unsigned long renegotiate_count;
    unsigned long byte_count;
    unsigned long renegotiate_timeout;
    unsigned long last_time;
} BIO_SSL;

static BIO_METHOD methods_sslp = {
    BIO_TYPE_SSL, "ssl",
    ssl_write,
    ssl_read,
    ssl_puts,
    NULL,                       /* ssl_gets, */
    ssl_ctrl,
    ssl_new,
    ssl_free,
    ssl_callback_ctrl,
};

BIO_METHOD *BIO_f_ssl(void)
{
    return (&methods_sslp);
}

static int ssl_new(BIO *bi)
{
    BIO_SSL *bs = OPENSSL_zalloc(sizeof(*bs));

    if (bs == NULL) {
        BIOerr(BIO_F_SSL_NEW, ERR_R_MALLOC_FAILURE);
        return (0);
    }
    bi->init = 0;
    bi->ptr = (char *)bs;
    bi->flags = 0;
    return (1);
}

static int ssl_free(BIO *a)
{
    BIO_SSL *bs;

    if (a == NULL)
        return (0);
    bs = (BIO_SSL *)a->ptr;
    if (bs->ssl != NULL)
        SSL_shutdown(bs->ssl);
    if (a->shutdown) {
        if (a->init)
            SSL_free(bs->ssl);
        a->init = 0;
        a->flags = 0;
    }
    OPENSSL_free(a->ptr);
    return (1);
}

static int ssl_read(BIO *b, char *out, int outl)
{
    int ret = 1;
    BIO_SSL *sb;
    SSL *ssl;
    int retry_reason = 0;
    int r = 0;

    if (out == NULL)
        return (0);
    sb = (BIO_SSL *)b->ptr;
    ssl = sb->ssl;

    BIO_clear_retry_flags(b);

    ret = SSL_read(ssl, out, outl);

    switch (SSL_get_error(ssl, ret)) {
    case SSL_ERROR_NONE:
        if (ret <= 0)
            break;
        if (sb->renegotiate_count > 0) {
            sb->byte_count += ret;
            if (sb->byte_count > sb->renegotiate_count) {
                sb->byte_count = 0;
                sb->num_renegotiates++;
                SSL_renegotiate(ssl);
                r = 1;
            }
        }
        if ((sb->renegotiate_timeout > 0) && (!r)) {
            unsigned long tm;

            tm = (unsigned long)time(NULL);
            if (tm > sb->last_time + sb->renegotiate_timeout) {
                sb->last_time = tm;
                sb->num_renegotiates++;
                SSL_renegotiate(ssl);
            }
        }

        break;
    case SSL_ERROR_WANT_READ:
        BIO_set_retry_read(b);
        break;
    case SSL_ERROR_WANT_WRITE:
        BIO_set_retry_write(b);
        break;
    case SSL_ERROR_WANT_X509_LOOKUP:
        BIO_set_retry_special(b);
        retry_reason = BIO_RR_SSL_X509_LOOKUP;
        break;
    case SSL_ERROR_WANT_ACCEPT:
        BIO_set_retry_special(b);
        retry_reason = BIO_RR_ACCEPT;
        break;
    case SSL_ERROR_WANT_CONNECT:
        BIO_set_retry_special(b);
        retry_reason = BIO_RR_CONNECT;
        break;
    case SSL_ERROR_SYSCALL:
    case SSL_ERROR_SSL:
    case SSL_ERROR_ZERO_RETURN:
    default:
        break;
    }

    b->retry_reason = retry_reason;
    return (ret);
}

static int ssl_write(BIO *b, const char *out, int outl)
{
    int ret, r = 0;
    int retry_reason = 0;
    SSL *ssl;
    BIO_SSL *bs;

    if (out == NULL)
        return (0);
    bs = (BIO_SSL *)b->ptr;
    ssl = bs->ssl;

    BIO_clear_retry_flags(b);

    /*
     * ret=SSL_do_handshake(ssl); if (ret > 0)
     */
    ret = SSL_write(ssl, out, outl);

    switch (SSL_get_error(ssl, ret)) {
    case SSL_ERROR_NONE:
        if (ret <= 0)
            break;
        if (bs->renegotiate_count > 0) {
            bs->byte_count += ret;
            if (bs->byte_count > bs->renegotiate_count) {
                bs->byte_count = 0;
                bs->num_renegotiates++;
                SSL_renegotiate(ssl);
                r = 1;
            }
        }
        if ((bs->renegotiate_timeout > 0) && (!r)) {
            unsigned long tm;

            tm = (unsigned long)time(NULL);
            if (tm > bs->last_time + bs->renegotiate_timeout) {
                bs->last_time = tm;
                bs->num_renegotiates++;
                SSL_renegotiate(ssl);
            }
        }
        break;
    case SSL_ERROR_WANT_WRITE:
        BIO_set_retry_write(b);
        break;
    case SSL_ERROR_WANT_READ:
        BIO_set_retry_read(b);
        break;
    case SSL_ERROR_WANT_X509_LOOKUP:
        BIO_set_retry_special(b);
        retry_reason = BIO_RR_SSL_X509_LOOKUP;
        break;
    case SSL_ERROR_WANT_CONNECT:
        BIO_set_retry_special(b);
        retry_reason = BIO_RR_CONNECT;
    case SSL_ERROR_SYSCALL:
    case SSL_ERROR_SSL:
    default:
        break;
    }

    b->retry_reason = retry_reason;
    return (ret);
}

static long ssl_ctrl(BIO *b, int cmd, long num, void *ptr)
{
    SSL **sslp, *ssl;
    BIO_SSL *bs;
    BIO *dbio, *bio;
    long ret = 1;

    bs = (BIO_SSL *)b->ptr;
    ssl = bs->ssl;
    if ((ssl == NULL) && (cmd != BIO_C_SET_SSL))
        return (0);
    switch (cmd) {
    case BIO_CTRL_RESET:
        SSL_shutdown(ssl);

        if (ssl->handshake_func == ssl->method->ssl_connect)
            SSL_set_connect_state(ssl);
        else if (ssl->handshake_func == ssl->method->ssl_accept)
            SSL_set_accept_state(ssl);

        if (!SSL_clear(ssl)) {
            ret = 0;
            break;
        }

        if (b->next_bio != NULL)
            ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
        else if (ssl->rbio != NULL)
            ret = BIO_ctrl(ssl->rbio, cmd, num, ptr);
        else
            ret = 1;
        break;
    case BIO_CTRL_INFO:
        ret = 0;
        break;
    case BIO_C_SSL_MODE:
        if (num)                /* client mode */
            SSL_set_connect_state(ssl);
        else
            SSL_set_accept_state(ssl);
        break;
    case BIO_C_SET_SSL_RENEGOTIATE_TIMEOUT:
        ret = bs->renegotiate_timeout;
        if (num < 60)
            num = 5;
        bs->renegotiate_timeout = (unsigned long)num;
        bs->last_time = (unsigned long)time(NULL);
        break;
    case BIO_C_SET_SSL_RENEGOTIATE_BYTES:
        ret = bs->renegotiate_count;
        if ((long)num >= 512)
            bs->renegotiate_count = (unsigned long)num;
        break;
    case BIO_C_GET_SSL_NUM_RENEGOTIATES:
        ret = bs->num_renegotiates;
        break;
    case BIO_C_SET_SSL:
        if (ssl != NULL) {
            ssl_free(b);
            if (!ssl_new(b))
                return 0;
        }
        b->shutdown = (int)num;
        ssl = (SSL *)ptr;
        ((BIO_SSL *)b->ptr)->ssl = ssl;
        bio = SSL_get_rbio(ssl);
        if (bio != NULL) {
            if (b->next_bio != NULL)
                BIO_push(bio, b->next_bio);
            b->next_bio = bio;
            CRYPTO_add(&bio->references, 1, CRYPTO_LOCK_BIO);
        }
        b->init = 1;
        break;
    case BIO_C_GET_SSL:
        if (ptr != NULL) {
            sslp = (SSL **)ptr;
            *sslp = ssl;
        } else
            ret = 0;
        break;
    case BIO_CTRL_GET_CLOSE:
        ret = b->shutdown;
        break;
    case BIO_CTRL_SET_CLOSE:
        b->shutdown = (int)num;
        break;
    case BIO_CTRL_WPENDING:
        ret = BIO_ctrl(ssl->wbio, cmd, num, ptr);
        break;
    case BIO_CTRL_PENDING:
        ret = SSL_pending(ssl);
        if (ret == 0)
            ret = BIO_pending(ssl->rbio);
        break;
    case BIO_CTRL_FLUSH:
        BIO_clear_retry_flags(b);
        ret = BIO_ctrl(ssl->wbio, cmd, num, ptr);
        BIO_copy_next_retry(b);
        break;
    case BIO_CTRL_PUSH:
        if ((b->next_bio != NULL) && (b->next_bio != ssl->rbio)) {
            SSL_set_bio(ssl, b->next_bio, b->next_bio);
            CRYPTO_add(&b->next_bio->references, 1, CRYPTO_LOCK_BIO);
        }
        break;
    case BIO_CTRL_POP:
        /* Only detach if we are the BIO explicitly being popped */
        if (b == ptr) {
            /*
             * Shouldn't happen in practice because the rbio and wbio are the
             * same when pushed.
             */
            if (ssl->rbio != ssl->wbio)
                BIO_free_all(ssl->wbio);
            if (b->next_bio != NULL)
                CRYPTO_add(&b->next_bio->references, -1, CRYPTO_LOCK_BIO);
            ssl->wbio = NULL;
            ssl->rbio = NULL;
        }
        break;
    case BIO_C_DO_STATE_MACHINE:
        BIO_clear_retry_flags(b);

        b->retry_reason = 0;
        ret = (int)SSL_do_handshake(ssl);

        switch (SSL_get_error(ssl, (int)ret)) {
        case SSL_ERROR_WANT_READ:
            BIO_set_flags(b, BIO_FLAGS_READ | BIO_FLAGS_SHOULD_RETRY);
            break;
        case SSL_ERROR_WANT_WRITE:
            BIO_set_flags(b, BIO_FLAGS_WRITE | BIO_FLAGS_SHOULD_RETRY);
            break;
        case SSL_ERROR_WANT_CONNECT:
            BIO_set_flags(b, BIO_FLAGS_IO_SPECIAL | BIO_FLAGS_SHOULD_RETRY);
            b->retry_reason = b->next_bio->retry_reason;
            break;
        case SSL_ERROR_WANT_X509_LOOKUP:
            BIO_set_retry_special(b);
            b->retry_reason = BIO_RR_SSL_X509_LOOKUP;
            break;
        default:
            break;
        }
        break;
    case BIO_CTRL_DUP:
        dbio = (BIO *)ptr;
        SSL_free(((BIO_SSL *)dbio->ptr)->ssl);
        ((BIO_SSL *)dbio->ptr)->ssl = SSL_dup(ssl);
        ((BIO_SSL *)dbio->ptr)->renegotiate_count =
            ((BIO_SSL *)b->ptr)->renegotiate_count;
        ((BIO_SSL *)dbio->ptr)->byte_count = ((BIO_SSL *)b->ptr)->byte_count;
        ((BIO_SSL *)dbio->ptr)->renegotiate_timeout =
            ((BIO_SSL *)b->ptr)->renegotiate_timeout;
        ((BIO_SSL *)dbio->ptr)->last_time = ((BIO_SSL *)b->ptr)->last_time;
        ret = (((BIO_SSL *)dbio->ptr)->ssl != NULL);
        break;
    case BIO_C_GET_FD:
        ret = BIO_ctrl(ssl->rbio, cmd, num, ptr);
        break;
    case BIO_CTRL_SET_CALLBACK:
        {
#if 0                           /* FIXME: Should this be used? -- Richard
                                 * Levitte */
            SSLerr(SSL_F_SSL_CTRL, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
            ret = -1;
#else
            ret = 0;
#endif
        }
        break;
    case BIO_CTRL_GET_CALLBACK:
        {
            void (**fptr) (const SSL *xssl, int type, int val);

            fptr = (void (**)(const SSL *xssl, int type, int val))ptr;
            *fptr = SSL_get_info_callback(ssl);
        }
        break;
    default:
        ret = BIO_ctrl(ssl->rbio, cmd, num, ptr);
        break;
    }
    return (ret);
}

static long ssl_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
{
    SSL *ssl;
    BIO_SSL *bs;
    long ret = 1;

    bs = (BIO_SSL *)b->ptr;
    ssl = bs->ssl;
    switch (cmd) {
    case BIO_CTRL_SET_CALLBACK:
        {
            /*
             * FIXME: setting this via a completely different prototype seems
             * like a crap idea
             */
            SSL_set_info_callback(ssl, (void (*)(const SSL *, int, int))fp);
        }
        break;
    default:
        ret = BIO_callback_ctrl(ssl->rbio, cmd, fp);
        break;
    }
    return (ret);
}

static int ssl_puts(BIO *bp, const char *str)
{
    int n, ret;

    n = strlen(str);
    ret = BIO_write(bp, str, n);
    return (ret);
}

BIO *BIO_new_buffer_ssl_connect(SSL_CTX *ctx)
{
#ifndef OPENSSL_NO_SOCK
    BIO *ret = NULL, *buf = NULL, *ssl = NULL;

    if ((buf = BIO_new(BIO_f_buffer())) == NULL)
        return (NULL);
    if ((ssl = BIO_new_ssl_connect(ctx)) == NULL)
        goto err;
    if ((ret = BIO_push(buf, ssl)) == NULL)
        goto err;
    return (ret);
 err:
    BIO_free(buf);
    BIO_free(ssl);
#endif
    return (NULL);
}

BIO *BIO_new_ssl_connect(SSL_CTX *ctx)
{
#ifndef OPENSSL_NO_SOCK
    BIO *ret = NULL, *con = NULL, *ssl = NULL;

    if ((con = BIO_new(BIO_s_connect())) == NULL)
        return (NULL);
    if ((ssl = BIO_new_ssl(ctx, 1)) == NULL)
        goto err;
    if ((ret = BIO_push(ssl, con)) == NULL)
        goto err;
    return (ret);
 err:
    BIO_free(con);
#endif
    return (NULL);
}

BIO *BIO_new_ssl(SSL_CTX *ctx, int client)
{
    BIO *ret;
    SSL *ssl;

    if ((ret = BIO_new(BIO_f_ssl())) == NULL)
        return (NULL);
    if ((ssl = SSL_new(ctx)) == NULL) {
        BIO_free(ret);
        return (NULL);
    }
    if (client)
        SSL_set_connect_state(ssl);
    else
        SSL_set_accept_state(ssl);

    BIO_set_ssl(ret, ssl, BIO_CLOSE);
    return (ret);
}

int BIO_ssl_copy_session_id(BIO *t, BIO *f)
{
    t = BIO_find_type(t, BIO_TYPE_SSL);
    f = BIO_find_type(f, BIO_TYPE_SSL);
    if ((t == NULL) || (f == NULL))
        return (0);
    if ((((BIO_SSL *)t->ptr)->ssl == NULL) ||
        (((BIO_SSL *)f->ptr)->ssl == NULL))
        return (0);
    if (!SSL_copy_session_id(((BIO_SSL *)t->ptr)->ssl, ((BIO_SSL *)f->ptr)->ssl))
        return 0;
    return (1);
}

void BIO_ssl_shutdown(BIO *b)
{
    SSL *s;

    while (b != NULL) {
        if (b->method->type == BIO_TYPE_SSL) {
            s = ((BIO_SSL *)b->ptr)->ssl;
            SSL_shutdown(s);
            break;
        }
        b = b->next_bio;
    }
}