openssl1.0/crypto/evp/evp_enc.c
2019-08-09 10:00:55 +02:00

706 lines
21 KiB
C

/* crypto/evp/evp_enc.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 "cryptlib.h"
#include <openssl/evp.h>
#include <openssl/err.h>
#include <openssl/rand.h>
#ifndef OPENSSL_NO_ENGINE
# include <openssl/engine.h>
#endif
#ifdef OPENSSL_FIPS
# include <openssl/fips.h>
#endif
#include "evp_locl.h"
#ifdef OPENSSL_FIPS
# define M_do_cipher(ctx, out, in, inl) FIPS_cipher(ctx, out, in, inl)
#else
# define M_do_cipher(ctx, out, in, inl) ctx->cipher->do_cipher(ctx, out, in, inl)
#endif
const char EVP_version[] = "EVP" OPENSSL_VERSION_PTEXT;
void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx)
{
memset(ctx, 0, sizeof(EVP_CIPHER_CTX));
/* ctx->cipher=NULL; */
}
EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void)
{
EVP_CIPHER_CTX *ctx = OPENSSL_malloc(sizeof(*ctx));
if (ctx)
EVP_CIPHER_CTX_init(ctx);
return ctx;
}
int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
const unsigned char *key, const unsigned char *iv, int enc)
{
if (cipher)
EVP_CIPHER_CTX_init(ctx);
return EVP_CipherInit_ex(ctx, cipher, NULL, key, iv, enc);
}
int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
ENGINE *impl, const unsigned char *key,
const unsigned char *iv, int enc)
{
if (enc == -1)
enc = ctx->encrypt;
else {
if (enc)
enc = 1;
ctx->encrypt = enc;
}
#ifndef OPENSSL_NO_ENGINE
/*
* Whether it's nice or not, "Inits" can be used on "Final"'d contexts so
* this context may already have an ENGINE! Try to avoid releasing the
* previous handle, re-querying for an ENGINE, and having a
* reinitialisation, when it may all be unecessary.
*/
if (ctx->engine && ctx->cipher && (!cipher ||
(cipher
&& (cipher->nid ==
ctx->cipher->nid))))
goto skip_to_init;
#endif
if (cipher) {
/*
* Ensure a context left lying around from last time is cleared (the
* previous check attempted to avoid this if the same ENGINE and
* EVP_CIPHER could be used).
*/
if (ctx->cipher) {
unsigned long flags = ctx->flags;
EVP_CIPHER_CTX_cleanup(ctx);
/* Restore encrypt and flags */
ctx->encrypt = enc;
ctx->flags = flags;
}
#ifndef OPENSSL_NO_ENGINE
if (impl) {
if (!ENGINE_init(impl)) {
EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
return 0;
}
} else
/* Ask if an ENGINE is reserved for this job */
impl = ENGINE_get_cipher_engine(cipher->nid);
if (impl) {
/* There's an ENGINE for this job ... (apparently) */
const EVP_CIPHER *c = ENGINE_get_cipher(impl, cipher->nid);
if (!c) {
/*
* One positive side-effect of US's export control history,
* is that we should at least be able to avoid using US
* mispellings of "initialisation"?
*/
EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
return 0;
}
/* We'll use the ENGINE's private cipher definition */
cipher = c;
/*
* Store the ENGINE functional reference so we know 'cipher' came
* from an ENGINE and we need to release it when done.
*/
ctx->engine = impl;
} else
ctx->engine = NULL;
#endif
#ifdef OPENSSL_FIPS
if (FIPS_mode()) {
const EVP_CIPHER *fcipher = NULL;
if (cipher)
fcipher = evp_get_fips_cipher(cipher);
if (fcipher)
cipher = fcipher;
return FIPS_cipherinit(ctx, cipher, key, iv, enc);
}
#endif
ctx->cipher = cipher;
if (ctx->cipher->ctx_size) {
ctx->cipher_data = OPENSSL_malloc(ctx->cipher->ctx_size);
if (!ctx->cipher_data) {
ctx->cipher = NULL;
EVPerr(EVP_F_EVP_CIPHERINIT_EX, ERR_R_MALLOC_FAILURE);
return 0;
}
} else {
ctx->cipher_data = NULL;
}
ctx->key_len = cipher->key_len;
/* Preserve wrap enable flag, zero everything else */
ctx->flags &= EVP_CIPHER_CTX_FLAG_WRAP_ALLOW;
if (ctx->cipher->flags & EVP_CIPH_CTRL_INIT) {
if (!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL)) {
ctx->cipher = NULL;
EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
return 0;
}
}
} else if (!ctx->cipher) {
EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_NO_CIPHER_SET);
return 0;
}
#ifndef OPENSSL_NO_ENGINE
skip_to_init:
#endif
#ifdef OPENSSL_FIPS
if (FIPS_mode())
return FIPS_cipherinit(ctx, cipher, key, iv, enc);
#endif
/* we assume block size is a power of 2 in *cryptUpdate */
OPENSSL_assert(ctx->cipher->block_size == 1
|| ctx->cipher->block_size == 8
|| ctx->cipher->block_size == 16);
if (!(ctx->flags & EVP_CIPHER_CTX_FLAG_WRAP_ALLOW)
&& EVP_CIPHER_CTX_mode(ctx) == EVP_CIPH_WRAP_MODE) {
EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_WRAP_MODE_NOT_ALLOWED);
return 0;
}
if (!(EVP_CIPHER_CTX_flags(ctx) & EVP_CIPH_CUSTOM_IV)) {
switch (EVP_CIPHER_CTX_mode(ctx)) {
case EVP_CIPH_STREAM_CIPHER:
case EVP_CIPH_ECB_MODE:
break;
case EVP_CIPH_CFB_MODE:
case EVP_CIPH_OFB_MODE:
ctx->num = 0;
/* fall-through */
case EVP_CIPH_CBC_MODE:
OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) <=
(int)sizeof(ctx->iv));
if (iv)
memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx));
memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx));
break;
case EVP_CIPH_CTR_MODE:
ctx->num = 0;
/* Don't reuse IV for CTR mode */
if (iv)
memcpy(ctx->iv, iv, EVP_CIPHER_CTX_iv_length(ctx));
break;
default:
return 0;
break;
}
}
if (key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) {
if (!ctx->cipher->init(ctx, key, iv, enc))
return 0;
}
ctx->buf_len = 0;
ctx->final_used = 0;
ctx->block_mask = ctx->cipher->block_size - 1;
return 1;
}
int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
const unsigned char *in, int inl)
{
if (ctx->encrypt)
return EVP_EncryptUpdate(ctx, out, outl, in, inl);
else
return EVP_DecryptUpdate(ctx, out, outl, in, inl);
}
int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
{
if (ctx->encrypt)
return EVP_EncryptFinal_ex(ctx, out, outl);
else
return EVP_DecryptFinal_ex(ctx, out, outl);
}
int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
{
if (ctx->encrypt)
return EVP_EncryptFinal(ctx, out, outl);
else
return EVP_DecryptFinal(ctx, out, outl);
}
int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
const unsigned char *key, const unsigned char *iv)
{
return EVP_CipherInit(ctx, cipher, key, iv, 1);
}
int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
ENGINE *impl, const unsigned char *key,
const unsigned char *iv)
{
return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1);
}
int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
const unsigned char *key, const unsigned char *iv)
{
return EVP_CipherInit(ctx, cipher, key, iv, 0);
}
int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
ENGINE *impl, const unsigned char *key,
const unsigned char *iv)
{
return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 0);
}
static int evp_EncryptDecryptUpdate(EVP_CIPHER_CTX *ctx,
unsigned char *out, int *outl,
const unsigned char *in, int inl)
{
int i, j, bl;
if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
i = M_do_cipher(ctx, out, in, inl);
if (i < 0)
return 0;
else
*outl = i;
return 1;
}
if (inl <= 0) {
*outl = 0;
return inl == 0;
}
if (ctx->buf_len == 0 && (inl & (ctx->block_mask)) == 0) {
if (M_do_cipher(ctx, out, in, inl)) {
*outl = inl;
return 1;
} else {
*outl = 0;
return 0;
}
}
i = ctx->buf_len;
bl = ctx->cipher->block_size;
OPENSSL_assert(bl <= (int)sizeof(ctx->buf));
if (i != 0) {
if (bl - i > inl) {
memcpy(&(ctx->buf[i]), in, inl);
ctx->buf_len += inl;
*outl = 0;
return 1;
} else {
j = bl - i;
memcpy(&(ctx->buf[i]), in, j);
if (!M_do_cipher(ctx, out, ctx->buf, bl))
return 0;
inl -= j;
in += j;
out += bl;
*outl = bl;
}
} else
*outl = 0;
i = inl & (bl - 1);
inl -= i;
if (inl > 0) {
if (!M_do_cipher(ctx, out, in, inl))
return 0;
*outl += inl;
}
if (i != 0)
memcpy(ctx->buf, &(in[inl]), i);
ctx->buf_len = i;
return 1;
}
int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
const unsigned char *in, int inl)
{
/* Prevent accidental use of decryption context when encrypting */
if (!ctx->encrypt) {
EVPerr(EVP_F_EVP_ENCRYPTUPDATE, EVP_R_INVALID_OPERATION);
return 0;
}
return evp_EncryptDecryptUpdate(ctx, out, outl, in, inl);
}
int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
{
int ret;
ret = EVP_EncryptFinal_ex(ctx, out, outl);
return ret;
}
int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
{
int n, ret;
unsigned int i, b, bl;
/* Prevent accidental use of decryption context when encrypting */
if (!ctx->encrypt) {
EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX, EVP_R_INVALID_OPERATION);
return 0;
}
if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
ret = M_do_cipher(ctx, out, NULL, 0);
if (ret < 0)
return 0;
else
*outl = ret;
return 1;
}
b = ctx->cipher->block_size;
OPENSSL_assert(b <= sizeof(ctx->buf));
if (b == 1) {
*outl = 0;
return 1;
}
bl = ctx->buf_len;
if (ctx->flags & EVP_CIPH_NO_PADDING) {
if (bl) {
EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX,
EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
return 0;
}
*outl = 0;
return 1;
}
n = b - bl;
for (i = bl; i < b; i++)
ctx->buf[i] = n;
ret = M_do_cipher(ctx, out, ctx->buf, b);
if (ret)
*outl = b;
return ret;
}
int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
const unsigned char *in, int inl)
{
int fix_len;
unsigned int b;
/* Prevent accidental use of encryption context when decrypting */
if (ctx->encrypt) {
EVPerr(EVP_F_EVP_DECRYPTUPDATE, EVP_R_INVALID_OPERATION);
return 0;
}
if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
fix_len = M_do_cipher(ctx, out, in, inl);
if (fix_len < 0) {
*outl = 0;
return 0;
} else
*outl = fix_len;
return 1;
}
if (inl <= 0) {
*outl = 0;
return inl == 0;
}
if (ctx->flags & EVP_CIPH_NO_PADDING)
return evp_EncryptDecryptUpdate(ctx, out, outl, in, inl);
b = ctx->cipher->block_size;
OPENSSL_assert(b <= sizeof(ctx->final));
if (ctx->final_used) {
memcpy(out, ctx->final, b);
out += b;
fix_len = 1;
} else
fix_len = 0;
if (!evp_EncryptDecryptUpdate(ctx, out, outl, in, inl))
return 0;
/*
* if we have 'decrypted' a multiple of block size, make sure we have a
* copy of this last block
*/
if (b > 1 && !ctx->buf_len) {
*outl -= b;
ctx->final_used = 1;
memcpy(ctx->final, &out[*outl], b);
} else
ctx->final_used = 0;
if (fix_len)
*outl += b;
return 1;
}
int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
{
int ret;
ret = EVP_DecryptFinal_ex(ctx, out, outl);
return ret;
}
int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
{
int i, n;
unsigned int b;
/* Prevent accidental use of encryption context when decrypting */
if (ctx->encrypt) {
EVPerr(EVP_F_EVP_DECRYPTFINAL_EX, EVP_R_INVALID_OPERATION);
return 0;
}
*outl = 0;
if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
i = M_do_cipher(ctx, out, NULL, 0);
if (i < 0)
return 0;
else
*outl = i;
return 1;
}
b = ctx->cipher->block_size;
if (ctx->flags & EVP_CIPH_NO_PADDING) {
if (ctx->buf_len) {
EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,
EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
return 0;
}
*outl = 0;
return 1;
}
if (b > 1) {
if (ctx->buf_len || !ctx->final_used) {
EVPerr(EVP_F_EVP_DECRYPTFINAL_EX, EVP_R_WRONG_FINAL_BLOCK_LENGTH);
return (0);
}
OPENSSL_assert(b <= sizeof(ctx->final));
/*
* The following assumes that the ciphertext has been authenticated.
* Otherwise it provides a padding oracle.
*/
n = ctx->final[b - 1];
if (n == 0 || n > (int)b) {
EVPerr(EVP_F_EVP_DECRYPTFINAL_EX, EVP_R_BAD_DECRYPT);
return (0);
}
for (i = 0; i < n; i++) {
if (ctx->final[--b] != n) {
EVPerr(EVP_F_EVP_DECRYPTFINAL_EX, EVP_R_BAD_DECRYPT);
return (0);
}
}
n = ctx->cipher->block_size - n;
for (i = 0; i < n; i++)
out[i] = ctx->final[i];
*outl = n;
} else
*outl = 0;
return (1);
}
void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)
{
if (ctx) {
EVP_CIPHER_CTX_cleanup(ctx);
OPENSSL_free(ctx);
}
}
int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *c)
{
#ifndef OPENSSL_FIPS
if (c->cipher != NULL) {
if (c->cipher->cleanup && !c->cipher->cleanup(c))
return 0;
/* Cleanse cipher context data */
if (c->cipher_data)
OPENSSL_cleanse(c->cipher_data, c->cipher->ctx_size);
}
if (c->cipher_data)
OPENSSL_free(c->cipher_data);
#endif
#ifndef OPENSSL_NO_ENGINE
if (c->engine)
/*
* The EVP_CIPHER we used belongs to an ENGINE, release the
* functional reference we held for this reason.
*/
ENGINE_finish(c->engine);
#endif
#ifdef OPENSSL_FIPS
FIPS_cipher_ctx_cleanup(c);
#endif
memset(c, 0, sizeof(EVP_CIPHER_CTX));
return 1;
}
int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *c, int keylen)
{
if (c->cipher->flags & EVP_CIPH_CUSTOM_KEY_LENGTH)
return EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_KEY_LENGTH, keylen, NULL);
if (c->key_len == keylen)
return 1;
if ((keylen > 0) && (c->cipher->flags & EVP_CIPH_VARIABLE_LENGTH)) {
c->key_len = keylen;
return 1;
}
EVPerr(EVP_F_EVP_CIPHER_CTX_SET_KEY_LENGTH, EVP_R_INVALID_KEY_LENGTH);
return 0;
}
int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad)
{
if (pad)
ctx->flags &= ~EVP_CIPH_NO_PADDING;
else
ctx->flags |= EVP_CIPH_NO_PADDING;
return 1;
}
int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)
{
int ret;
if (!ctx->cipher) {
EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_NO_CIPHER_SET);
return 0;
}
if (!ctx->cipher->ctrl) {
EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_NOT_IMPLEMENTED);
return 0;
}
ret = ctx->cipher->ctrl(ctx, type, arg, ptr);
if (ret == -1) {
EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL,
EVP_R_CTRL_OPERATION_NOT_IMPLEMENTED);
return 0;
}
return ret;
}
int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key)
{
if (ctx->cipher->flags & EVP_CIPH_RAND_KEY)
return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_RAND_KEY, 0, key);
if (RAND_bytes(key, ctx->key_len) <= 0)
return 0;
return 1;
}
int EVP_CIPHER_CTX_copy(EVP_CIPHER_CTX *out, const EVP_CIPHER_CTX *in)
{
if ((in == NULL) || (in->cipher == NULL)) {
EVPerr(EVP_F_EVP_CIPHER_CTX_COPY, EVP_R_INPUT_NOT_INITIALIZED);
return 0;
}
#ifndef OPENSSL_NO_ENGINE
/* Make sure it's safe to copy a cipher context using an ENGINE */
if (in->engine && !ENGINE_init(in->engine)) {
EVPerr(EVP_F_EVP_CIPHER_CTX_COPY, ERR_R_ENGINE_LIB);
return 0;
}
#endif
EVP_CIPHER_CTX_cleanup(out);
memcpy(out, in, sizeof(*out));
if (in->cipher_data && in->cipher->ctx_size) {
out->cipher_data = OPENSSL_malloc(in->cipher->ctx_size);
if (!out->cipher_data) {
out->cipher = NULL;
EVPerr(EVP_F_EVP_CIPHER_CTX_COPY, ERR_R_MALLOC_FAILURE);
return 0;
}
memcpy(out->cipher_data, in->cipher_data, in->cipher->ctx_size);
}
if (in->cipher->flags & EVP_CIPH_CUSTOM_COPY)
if (!in->cipher->ctrl((EVP_CIPHER_CTX *)in, EVP_CTRL_COPY, 0, out)) {
out->cipher = NULL;
EVPerr(EVP_F_EVP_CIPHER_CTX_COPY, EVP_R_INITIALIZATION_ERROR);
return 0;
}
return 1;
}