/src/openssl/crypto/evp/bio_enc.c

Source
/*
 * Copyright 1995-2025 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the Apache License 2.0 (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

#define OPENSSL_SUPPRESS_DEPRECATED /* for BIO_get_callback */

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

static int enc_write(BIO *h, const char *buf, int num);
static int enc_read(BIO *h, char *buf, int size);
static long enc_ctrl(BIO *h, int cmd, long arg1, void *arg2);
static int enc_new(BIO *h);
static int enc_free(BIO *data);
static long enc_callback_ctrl(BIO *h, int cmd, BIO_info_cb *fps);
/*
 * ENC_BLOCK_SIZE has been sized to handle ciphers that do not support streaming.
 * i.e. For AES Key wrapping of larger PQ private keys the buffer needs to be
 * large enough to process the input/output in one EVP_CipherUpdate() call.
 */
#define ENC_BLOCK_SIZE (1024 * 8)
#define ENC_MIN_CHUNK (256)
#define BUF_OFFSET (ENC_MIN_CHUNK + EVP_MAX_BLOCK_LENGTH)

typedef struct enc_struct {
    int buf_len;
    int buf_off;
    int cont; /* <= 0 when finished */
    int finished;
    int ok; /* bad decrypt */
    EVP_CIPHER_CTX *cipher;
    unsigned char *read_start, *read_end;
    /*
     * buf is larger than ENC_BLOCK_SIZE because EVP_DecryptUpdate can return
     * up to a block more data than is presented to it
     */
    unsigned char buf[BUF_OFFSET + ENC_BLOCK_SIZE];
} BIO_ENC_CTX;

static const BIO_METHOD methods_enc = {
    BIO_TYPE_CIPHER,
    "cipher",
    bwrite_conv,
    enc_write,
    bread_conv,
    enc_read,
    NULL, /* enc_puts, */
    NULL, /* enc_gets, */
    enc_ctrl,
    enc_new,
    enc_free,
    enc_callback_ctrl,
};

const BIO_METHOD *BIO_f_cipher(void)
{
    return &methods_enc;
}

static int enc_new(BIO *bi)
{
    BIO_ENC_CTX *ctx;

    if ((ctx = OPENSSL_zalloc(sizeof(*ctx))) == NULL)
        return 0;

    ctx->cipher = EVP_CIPHER_CTX_new();
    if (ctx->cipher == NULL) {
        OPENSSL_free(ctx);
        return 0;
    }
    ctx->cont = 1;
    ctx->ok = 1;
    ctx->read_end = ctx->read_start = &(ctx->buf[BUF_OFFSET]);
    BIO_set_data(bi, ctx);
    BIO_set_init(bi, 1);

    return 1;
}

static int enc_free(BIO *a)
{
    BIO_ENC_CTX *b;

    if (a == NULL)
        return 0;

    b = BIO_get_data(a);
    if (b == NULL)
        return 0;

    EVP_CIPHER_CTX_free(b->cipher);
    OPENSSL_clear_free(b, sizeof(BIO_ENC_CTX));
    BIO_set_data(a, NULL);
    BIO_set_init(a, 0);

    return 1;
}

static int enc_read(BIO *b, char *out, int outl)
{
    int ret = 0, i, blocksize;
    BIO_ENC_CTX *ctx;
    BIO *next;

    if (out == NULL)
        return 0;
    ctx = BIO_get_data(b);

    next = BIO_next(b);
    if ((ctx == NULL) || (next == NULL))
        return 0;

    /* First check if there are bytes decoded/encoded */
    if (ctx->buf_len > 0) {
        i = ctx->buf_len - ctx->buf_off;
        if (i > outl)
            i = outl;
        memcpy(out, &(ctx->buf[ctx->buf_off]), i);
        ret = i;
        out += i;
        outl -= i;
        ctx->buf_off += i;
        if (ctx->buf_len == ctx->buf_off) {
            ctx->buf_len = 0;
            ctx->buf_off = 0;
        }
    }

    blocksize = EVP_CIPHER_CTX_get_block_size(ctx->cipher);

    if (blocksize == 0)
        return 0;

    if (blocksize == 1)
        blocksize = 0;

    /*
     * At this point, we have room of outl bytes and an empty buffer, so we
     * should read in some more.
     */

    while (outl > 0) {
        if (ctx->cont <= 0)
            break;

        if (ctx->read_start == ctx->read_end) { /* time to read more data */
            ctx->read_end = ctx->read_start = &(ctx->buf[BUF_OFFSET]);
            i = BIO_read(next, ctx->read_start, ENC_BLOCK_SIZE);
            if (i > 0)
                ctx->read_end += i;
        } else {
            i = (int)(ctx->read_end - ctx->read_start);
        }

        if (i <= 0) {
            /* Should be continue next time we are called? */
            if (!BIO_should_retry(next)) {
                ctx->cont = i;
                ctx->finished = 1;
                i = EVP_CipherFinal_ex(ctx->cipher,
                    ctx->buf, &(ctx->buf_len));
                ctx->ok = i;
                ctx->buf_off = 0;
            } else {
                ret = (ret == 0) ? i : ret;
                break;
            }
        } else {
            if (outl > ENC_MIN_CHUNK) {
                /*
                 * Depending on flags block cipher decrypt can write
                 * one extra block and then back off, i.e. output buffer
                 * has to accommodate extra block...
                 */
                int j = outl - blocksize, buf_len;

                if (!EVP_CipherUpdate(ctx->cipher,
                        (unsigned char *)out, &buf_len,
                        ctx->read_start, i > j ? j : i)) {
                    BIO_clear_retry_flags(b);
                    return 0;
                }
                ret += buf_len;
                out += buf_len;
                outl -= buf_len;

                if ((i -= j) <= 0) {
                    ctx->read_start = ctx->read_end;
                    continue;
                }
                ctx->read_start += j;
            }
            if (i > ENC_MIN_CHUNK)
                i = ENC_MIN_CHUNK;
            if (!EVP_CipherUpdate(ctx->cipher,
                    ctx->buf, &ctx->buf_len,
                    ctx->read_start, i)) {
                BIO_clear_retry_flags(b);
                ctx->ok = 0;
                return 0;
            }
            ctx->read_start += i;
            ctx->cont = 1;
            /*
             * Note: it is possible for EVP_CipherUpdate to decrypt zero
             * bytes because this is or looks like the final block: if this
             * happens we should retry and either read more data or decrypt
             * the final block
             */
            if (ctx->buf_len == 0)
                continue;
        }

        if (ctx->buf_len <= outl)
            i = ctx->buf_len;
        else
            i = outl;
        if (i <= 0)
            break;
        memcpy(out, ctx->buf, i);
        ret += i;
        ctx->buf_off = i;
        outl -= i;
        out += i;
    }

    BIO_clear_retry_flags(b);
    BIO_copy_next_retry(b);
    return ((ret == 0) ? ctx->cont : ret);
}

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

    ctx = BIO_get_data(b);
    next = BIO_next(b);
    if ((ctx == NULL) || (next == NULL))
        return 0;

    ret = inl;

    BIO_clear_retry_flags(b);
    n = ctx->buf_len - ctx->buf_off;
    while (n > 0) {
        i = BIO_write(next, &(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;
        if (!EVP_CipherUpdate(ctx->cipher,
                ctx->buf, &ctx->buf_len,
                (const unsigned char *)in, n)) {
            BIO_clear_retry_flags(b);
            ctx->ok = 0;
            return 0;
        }
        inl -= n;
        in += n;

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

static long enc_ctrl(BIO *b, int cmd, long num, void *ptr)
{
    BIO *dbio;
    BIO_ENC_CTX *ctx, *dctx;
    long ret = 1;
    int i;
    EVP_CIPHER_CTX **c_ctx;
    BIO *next;
    int pend;

    ctx = BIO_get_data(b);
    next = BIO_next(b);
    /*
     * If there is no ctx, BIO_read() returns 0, which means EOF.
     * BIO_eof() should return 1 in this case.
     */
    if (ctx == NULL)
        return cmd == BIO_CTRL_EOF;

    switch (cmd) {
    case BIO_CTRL_RESET:
        ctx->ok = 1;
        ctx->finished = 0;
        if (!EVP_CipherInit_ex(ctx->cipher, NULL, NULL, NULL, NULL,
                EVP_CIPHER_CTX_is_encrypting(ctx->cipher)))
            return 0;
        ret = BIO_ctrl(next, cmd, num, ptr);
        break;
    case BIO_CTRL_EOF: /* More to read */
        if (ctx->cont <= 0)
            ret = 1;
        else
            /*
             * If there is no next BIO, BIO_read() returns 0, which means EOF.
             * BIO_eof() should return 1 in this case.
             */
            ret = (next == NULL) ? 1 : BIO_ctrl(next, cmd, num, ptr);
        break;
    case BIO_CTRL_WPENDING:
        ret = ctx->buf_len - ctx->buf_off;
        if (ret <= 0)
            ret = BIO_ctrl(next, 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(next, cmd, num, ptr);
        break;
    case BIO_CTRL_FLUSH:
        /* do a final write */
    again:
        while (ctx->buf_len != ctx->buf_off) {
            pend = ctx->buf_len - ctx->buf_off;
            i = enc_write(b, NULL, 0);
            /*
             * i should never be > 0 here because we didn't ask to write any
             * new data. We stop if we get an error or we failed to make any
             * progress writing pending data.
             */
            if (i < 0 || (ctx->buf_len - ctx->buf_off) == pend)
                return i;
        }

        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(next, cmd, num, ptr);
        BIO_copy_next_retry(b);
        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(next, cmd, num, ptr);
        BIO_copy_next_retry(b);
        break;
    case BIO_C_GET_CIPHER_CTX:
        c_ctx = (EVP_CIPHER_CTX **)ptr;
        *c_ctx = ctx->cipher;
        BIO_set_init(b, 1);
        break;
    case BIO_CTRL_DUP:
        dbio = (BIO *)ptr;
        dctx = BIO_get_data(dbio);
        dctx->cipher = EVP_CIPHER_CTX_new();
        if (dctx->cipher == NULL)
            return 0;
        ret = EVP_CIPHER_CTX_copy(dctx->cipher, ctx->cipher);
        if (ret)
            BIO_set_init(dbio, 1);
        break;
    default:
        ret = BIO_ctrl(next, cmd, num, ptr);
        break;
    }
    return ret;
}

static long enc_callback_ctrl(BIO *b, int cmd, BIO_info_cb *fp)
{
    BIO *next = BIO_next(b);

    if (next == NULL)
        return 0;

    return BIO_callback_ctrl(next, cmd, fp);
}

int BIO_set_cipher(BIO *b, const EVP_CIPHER *c, const unsigned char *k,
    const unsigned char *i, int e)
{
    BIO_ENC_CTX *ctx;
    BIO_callback_fn_ex callback_ex;
#ifndef OPENSSL_NO_DEPRECATED_3_0
    long (*callback)(struct bio_st *, int, const char *, int, long, long) = NULL;
#endif

    ctx = BIO_get_data(b);
    if (ctx == NULL)
        return 0;

    if ((callback_ex = BIO_get_callback_ex(b)) != NULL) {
        if (callback_ex(b, BIO_CB_CTRL, (const char *)c, 0, BIO_CTRL_SET,
                e, 1, NULL)
            <= 0)
            return 0;
    }
#ifndef OPENSSL_NO_DEPRECATED_3_0
    else {
        callback = BIO_get_callback(b);

        if ((callback != NULL) && (callback(b, BIO_CB_CTRL, (const char *)c, BIO_CTRL_SET, e, 0L) <= 0))
            return 0;
    }
#endif

    BIO_set_init(b, 1);

    if (!EVP_CipherInit_ex(ctx->cipher, c, NULL, k, i, e))
        return 0;

    if (callback_ex != NULL)
        return callback_ex(b, BIO_CB_CTRL | BIO_CB_RETURN, (const char *)c, 0,
            BIO_CTRL_SET, e, 1, NULL);
#ifndef OPENSSL_NO_DEPRECATED_3_0
    else if (callback != NULL)
        return callback(b, BIO_CB_CTRL, (const char *)c, BIO_CTRL_SET, e, 1L);
#endif
    return 1;
}

Coverage Report

Created: 2026-02-22 06:11

Line	Count	Source
1		/*
2		* Copyright 1995-2025 The OpenSSL Project Authors. All Rights Reserved.
3		*
4		* Licensed under the Apache License 2.0 (the "License"). You may not use
5		* this file except in compliance with the License. You can obtain a copy
6		* in the file LICENSE in the source distribution or at
7		* https://www.openssl.org/source/license.html
8		*/
9
10		#define OPENSSL_SUPPRESS_DEPRECATED /* for BIO_get_callback */
11
12		#include <stdio.h>
13		#include <errno.h>
14		#include "internal/cryptlib.h"
15		#include <openssl/buffer.h>
16		#include <openssl/evp.h>
17		#include "internal/bio.h"
18
19		static int enc_write(BIO h, const char buf, int num);
20		static int enc_read(BIO h, char buf, int size);
21		static long enc_ctrl(BIO h, int cmd, long arg1, void arg2);
22		static int enc_new(BIO *h);
23		static int enc_free(BIO *data);
24		static long enc_callback_ctrl(BIO h, int cmd, BIO_info_cb fps);
25		/*
26		* ENC_BLOCK_SIZE has been sized to handle ciphers that do not support streaming.
27		* i.e. For AES Key wrapping of larger PQ private keys the buffer needs to be
28		* large enough to process the input/output in one EVP_CipherUpdate() call.
29		*/
30	0	#define ENC_BLOCK_SIZE (1024 * 8)
31	0	#define ENC_MIN_CHUNK (256)
32	0	#define BUF_OFFSET (ENC_MIN_CHUNK + EVP_MAX_BLOCK_LENGTH)
33
34		typedef struct enc_struct {
35		int buf_len;
36		int buf_off;
37		int cont; /* <= 0 when finished */
38		int finished;
39		int ok; /* bad decrypt */
40		EVP_CIPHER_CTX *cipher;
41		unsigned char read_start, read_end;
42		/*
43		* buf is larger than ENC_BLOCK_SIZE because EVP_DecryptUpdate can return
44		* up to a block more data than is presented to it
45		*/
46		unsigned char buf[BUF_OFFSET + ENC_BLOCK_SIZE];
47		} BIO_ENC_CTX;
48
49		static const BIO_METHOD methods_enc = {
50		BIO_TYPE_CIPHER,
51		"cipher",
52		bwrite_conv,
53		enc_write,
54		bread_conv,
55		enc_read,
56		NULL, /* enc_puts, */
57		NULL, /* enc_gets, */
58		enc_ctrl,
59		enc_new,
60		enc_free,
61		enc_callback_ctrl,
62		};
63
64		const BIO_METHOD *BIO_f_cipher(void)
65	0	{
66	0	return &methods_enc;
67	0	}
68
69		static int enc_new(BIO *bi)
70	0	{
71	0	BIO_ENC_CTX *ctx;
72
73	0	if ((ctx = OPENSSL_zalloc(sizeof(*ctx))) == NULL)
74	0	return 0;
75
76	0	ctx->cipher = EVP_CIPHER_CTX_new();
77	0	if (ctx->cipher == NULL) {
78	0	OPENSSL_free(ctx);
79	0	return 0;
80	0	}
81	0	ctx->cont = 1;
82	0	ctx->ok = 1;
83	0	ctx->read_end = ctx->read_start = &(ctx->buf[BUF_OFFSET]);
84	0	BIO_set_data(bi, ctx);
85	0	BIO_set_init(bi, 1);
86
87	0	return 1;
88	0	}
89
90		static int enc_free(BIO *a)
91	0	{
92	0	BIO_ENC_CTX *b;
93
94	0	if (a == NULL)
95	0	return 0;
96
97	0	b = BIO_get_data(a);
98	0	if (b == NULL)
99	0	return 0;
100
101	0	EVP_CIPHER_CTX_free(b->cipher);
102	0	OPENSSL_clear_free(b, sizeof(BIO_ENC_CTX));
103	0	BIO_set_data(a, NULL);
104	0	BIO_set_init(a, 0);
105
106	0	return 1;
107	0	}
108
109		static int enc_read(BIO b, char out, int outl)
110	0	{
111	0	int ret = 0, i, blocksize;
112	0	BIO_ENC_CTX *ctx;
113	0	BIO *next;
114
115	0	if (out == NULL)
116	0	return 0;
117	0	ctx = BIO_get_data(b);
118
119	0	next = BIO_next(b);
120	0	if ((ctx == NULL) \|\| (next == NULL))
121	0	return 0;
122
123		/* First check if there are bytes decoded/encoded */
124	0	if (ctx->buf_len > 0) {
125	0	i = ctx->buf_len - ctx->buf_off;
126	0	if (i > outl)
127	0	i = outl;
128	0	memcpy(out, &(ctx->buf[ctx->buf_off]), i);
129	0	ret = i;
130	0	out += i;
131	0	outl -= i;
132	0	ctx->buf_off += i;
133	0	if (ctx->buf_len == ctx->buf_off) {
134	0	ctx->buf_len = 0;
135	0	ctx->buf_off = 0;
136	0	}
137	0	}
138
139	0	blocksize = EVP_CIPHER_CTX_get_block_size(ctx->cipher);
140
141	0	if (blocksize == 0)
142	0	return 0;
143
144	0	if (blocksize == 1)
145	0	blocksize = 0;
146
147		/*
148		* At this point, we have room of outl bytes and an empty buffer, so we
149		* should read in some more.
150		*/
151
152	0	while (outl > 0) {
153	0	if (ctx->cont <= 0)
154	0	break;
155
156	0	if (ctx->read_start == ctx->read_end) { /* time to read more data */
157	0	ctx->read_end = ctx->read_start = &(ctx->buf[BUF_OFFSET]);
158	0	i = BIO_read(next, ctx->read_start, ENC_BLOCK_SIZE);
159	0	if (i > 0)
160	0	ctx->read_end += i;
161	0	} else {
162	0	i = (int)(ctx->read_end - ctx->read_start);
163	0	}
164
165	0	if (i <= 0) {
166		/* Should be continue next time we are called? */
167	0	if (!BIO_should_retry(next)) {
168	0	ctx->cont = i;
169	0	ctx->finished = 1;
170	0	i = EVP_CipherFinal_ex(ctx->cipher,
171	0	ctx->buf, &(ctx->buf_len));
172	0	ctx->ok = i;
173	0	ctx->buf_off = 0;
174	0	} else {
175	0	ret = (ret == 0) ? i : ret;
176	0	break;
177	0	}
178	0	} else {
179	0	if (outl > ENC_MIN_CHUNK) {
180		/*
181		* Depending on flags block cipher decrypt can write
182		* one extra block and then back off, i.e. output buffer
183		* has to accommodate extra block...
184		*/
185	0	int j = outl - blocksize, buf_len;
186
187	0	if (!EVP_CipherUpdate(ctx->cipher,
188	0	(unsigned char *)out, &buf_len,
189	0	ctx->read_start, i > j ? j : i)) {
190	0	BIO_clear_retry_flags(b);
191	0	return 0;
192	0	}
193	0	ret += buf_len;
194	0	out += buf_len;
195	0	outl -= buf_len;
196
197	0	if ((i -= j) <= 0) {
198	0	ctx->read_start = ctx->read_end;
199	0	continue;
200	0	}
201	0	ctx->read_start += j;
202	0	}
203	0	if (i > ENC_MIN_CHUNK)
204	0	i = ENC_MIN_CHUNK;
205	0	if (!EVP_CipherUpdate(ctx->cipher,
206	0	ctx->buf, &ctx->buf_len,
207	0	ctx->read_start, i)) {
208	0	BIO_clear_retry_flags(b);
209	0	ctx->ok = 0;
210	0	return 0;
211	0	}
212	0	ctx->read_start += i;
213	0	ctx->cont = 1;
214		/*
215		* Note: it is possible for EVP_CipherUpdate to decrypt zero
216		* bytes because this is or looks like the final block: if this
217		* happens we should retry and either read more data or decrypt
218		* the final block
219		*/
220	0	if (ctx->buf_len == 0)
221	0	continue;
222	0	}
223
224	0	if (ctx->buf_len <= outl)
225	0	i = ctx->buf_len;
226	0	else
227	0	i = outl;
228	0	if (i <= 0)
229	0	break;
230	0	memcpy(out, ctx->buf, i);
231	0	ret += i;
232	0	ctx->buf_off = i;
233	0	outl -= i;
234	0	out += i;
235	0	}
236
237	0	BIO_clear_retry_flags(b);
238	0	BIO_copy_next_retry(b);
239	0	return ((ret == 0) ? ctx->cont : ret);
240	0	}
241
242		static int enc_write(BIO b, const char in, int inl)
243	0	{
244	0	int ret = 0, n, i;
245	0	BIO_ENC_CTX *ctx;
246	0	BIO *next;
247
248	0	ctx = BIO_get_data(b);
249	0	next = BIO_next(b);
250	0	if ((ctx == NULL) \|\| (next == NULL))
251	0	return 0;
252
253	0	ret = inl;
254
255	0	BIO_clear_retry_flags(b);
256	0	n = ctx->buf_len - ctx->buf_off;
257	0	while (n > 0) {
258	0	i = BIO_write(next, &(ctx->buf[ctx->buf_off]), n);
259	0	if (i <= 0) {
260	0	BIO_copy_next_retry(b);
261	0	return i;
262	0	}
263	0	ctx->buf_off += i;
264	0	n -= i;
265	0	}
266		/* at this point all pending data has been written */
267
268	0	if ((in == NULL) \|\| (inl <= 0))
269	0	return 0;
270
271	0	ctx->buf_off = 0;
272	0	while (inl > 0) {
273	0	n = (inl > ENC_BLOCK_SIZE) ? ENC_BLOCK_SIZE : inl;
274	0	if (!EVP_CipherUpdate(ctx->cipher,
275	0	ctx->buf, &ctx->buf_len,
276	0	(const unsigned char *)in, n)) {
277	0	BIO_clear_retry_flags(b);
278	0	ctx->ok = 0;
279	0	return 0;
280	0	}
281	0	inl -= n;
282	0	in += n;
283
284	0	ctx->buf_off = 0;
285	0	n = ctx->buf_len;
286	0	while (n > 0) {
287	0	i = BIO_write(next, &(ctx->buf[ctx->buf_off]), n);
288	0	if (i <= 0) {
289	0	BIO_copy_next_retry(b);
290	0	return (ret == inl) ? i : ret - inl;
291	0	}
292	0	n -= i;
293	0	ctx->buf_off += i;
294	0	}
295	0	ctx->buf_len = 0;
296	0	ctx->buf_off = 0;
297	0	}
298	0	BIO_copy_next_retry(b);
299	0	return ret;
300	0	}
301
302		static long enc_ctrl(BIO b, int cmd, long num, void ptr)
303	0	{
304	0	BIO *dbio;
305	0	BIO_ENC_CTX ctx, dctx;
306	0	long ret = 1;
307	0	int i;
308	0	EVP_CIPHER_CTX **c_ctx;
309	0	BIO *next;
310	0	int pend;
311
312	0	ctx = BIO_get_data(b);
313	0	next = BIO_next(b);
314		/*
315		* If there is no ctx, BIO_read() returns 0, which means EOF.
316		* BIO_eof() should return 1 in this case.
317		*/
318	0	if (ctx == NULL)
319	0	return cmd == BIO_CTRL_EOF;
320
321	0	switch (cmd) {
322	0	case BIO_CTRL_RESET:
323	0	ctx->ok = 1;
324	0	ctx->finished = 0;
325	0	if (!EVP_CipherInit_ex(ctx->cipher, NULL, NULL, NULL, NULL,
326	0	EVP_CIPHER_CTX_is_encrypting(ctx->cipher)))
327	0	return 0;
328	0	ret = BIO_ctrl(next, cmd, num, ptr);
329	0	break;
330	0	case BIO_CTRL_EOF: /* More to read */
331	0	if (ctx->cont <= 0)
332	0	ret = 1;
333	0	else
334		/*
335		* If there is no next BIO, BIO_read() returns 0, which means EOF.
336		* BIO_eof() should return 1 in this case.
337		*/
338	0	ret = (next == NULL) ? 1 : BIO_ctrl(next, cmd, num, ptr);
339	0	break;
340	0	case BIO_CTRL_WPENDING:
341	0	ret = ctx->buf_len - ctx->buf_off;
342	0	if (ret <= 0)
343	0	ret = BIO_ctrl(next, cmd, num, ptr);
344	0	break;
345	0	case BIO_CTRL_PENDING: /* More to read in buffer */
346	0	ret = ctx->buf_len - ctx->buf_off;
347	0	if (ret <= 0)
348	0	ret = BIO_ctrl(next, cmd, num, ptr);
349	0	break;
350	0	case BIO_CTRL_FLUSH:
351		/* do a final write */
352	0	again:
353	0	while (ctx->buf_len != ctx->buf_off) {
354	0	pend = ctx->buf_len - ctx->buf_off;
355	0	i = enc_write(b, NULL, 0);
356		/*
357		* i should never be > 0 here because we didn't ask to write any
358		* new data. We stop if we get an error or we failed to make any
359		* progress writing pending data.
360		*/
361	0	if (i < 0 \|\| (ctx->buf_len - ctx->buf_off) == pend)
362	0	return i;
363	0	}
364
365	0	if (!ctx->finished) {
366	0	ctx->finished = 1;
367	0	ctx->buf_off = 0;
368	0	ret = EVP_CipherFinal_ex(ctx->cipher,
369	0	(unsigned char *)ctx->buf,
370	0	&(ctx->buf_len));
371	0	ctx->ok = (int)ret;
372	0	if (ret <= 0)
373	0	break;
374
375		/* push out the bytes */
376	0	goto again;
377	0	}
378
379		/* Finally flush the underlying BIO */
380	0	ret = BIO_ctrl(next, cmd, num, ptr);
381	0	BIO_copy_next_retry(b);
382	0	break;
383	0	case BIO_C_GET_CIPHER_STATUS:
384	0	ret = (long)ctx->ok;
385	0	break;
386	0	case BIO_C_DO_STATE_MACHINE:
387	0	BIO_clear_retry_flags(b);
388	0	ret = BIO_ctrl(next, cmd, num, ptr);
389	0	BIO_copy_next_retry(b);
390	0	break;
391	0	case BIO_C_GET_CIPHER_CTX:
392	0	c_ctx = (EVP_CIPHER_CTX **)ptr;
393	0	*c_ctx = ctx->cipher;
394	0	BIO_set_init(b, 1);
395	0	break;
396	0	case BIO_CTRL_DUP:
397	0	dbio = (BIO *)ptr;
398	0	dctx = BIO_get_data(dbio);
399	0	dctx->cipher = EVP_CIPHER_CTX_new();
400	0	if (dctx->cipher == NULL)
401	0	return 0;
402	0	ret = EVP_CIPHER_CTX_copy(dctx->cipher, ctx->cipher);
403	0	if (ret)
404	0	BIO_set_init(dbio, 1);
405	0	break;
406	0	default:
407	0	ret = BIO_ctrl(next, cmd, num, ptr);
408	0	break;
409	0	}
410	0	return ret;
411	0	}
412
413		static long enc_callback_ctrl(BIO b, int cmd, BIO_info_cb fp)
414	0	{
415	0	BIO *next = BIO_next(b);
416
417	0	if (next == NULL)
418	0	return 0;
419
420	0	return BIO_callback_ctrl(next, cmd, fp);
421	0	}
422
423		int BIO_set_cipher(BIO b, const EVP_CIPHER c, const unsigned char *k,
424		const unsigned char *i, int e)
425	0	{
426	0	BIO_ENC_CTX *ctx;
427	0	BIO_callback_fn_ex callback_ex;
428	0	#ifndef OPENSSL_NO_DEPRECATED_3_0
429	0	long (callback)(struct bio_st , int, const char *, int, long, long) = NULL;
430	0	#endif
431
432	0	ctx = BIO_get_data(b);
433	0	if (ctx == NULL)
434	0	return 0;
435
436	0	if ((callback_ex = BIO_get_callback_ex(b)) != NULL) {
437	0	if (callback_ex(b, BIO_CB_CTRL, (const char *)c, 0, BIO_CTRL_SET,
438	0	e, 1, NULL)
439	0	<= 0)
440	0	return 0;
441	0	}
442	0	#ifndef OPENSSL_NO_DEPRECATED_3_0
443	0	else {
444	0	callback = BIO_get_callback(b);
445
446	0	if ((callback != NULL) && (callback(b, BIO_CB_CTRL, (const char *)c, BIO_CTRL_SET, e, 0L) <= 0))
447	0	return 0;
448	0	}
449	0	#endif
450
451	0	BIO_set_init(b, 1);
452
453	0	if (!EVP_CipherInit_ex(ctx->cipher, c, NULL, k, i, e))
454	0	return 0;
455
456	0	if (callback_ex != NULL)
457	0	return callback_ex(b, BIO_CB_CTRL \| BIO_CB_RETURN, (const char *)c, 0,
458	0	BIO_CTRL_SET, e, 1, NULL);
459	0	#ifndef OPENSSL_NO_DEPRECATED_3_0
460	0	else if (callback != NULL)
461	0	return callback(b, BIO_CB_CTRL, (const char *)c, BIO_CTRL_SET, e, 1L);
462	0	#endif
463	0	return 1;
464	0	}