720 lines
21 KiB
C
720 lines
21 KiB
C
/*
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* Copyright 1995-2022 The OpenSSL Project Authors. All Rights Reserved.
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*
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* Licensed under the OpenSSL license (the "License"). You may not use
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* this file except in compliance with the License. You can obtain a copy
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* in the file LICENSE in the source distribution or at
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* https://www.openssl.org/source/license.html
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*/
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#include <stdio.h>
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#include <limits.h>
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#include <assert.h>
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#include "internal/cryptlib.h"
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#include <openssl/evp.h>
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#include <openssl/err.h>
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#include <openssl/rand.h>
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#include <openssl/rand_drbg.h>
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#include <openssl/engine.h>
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#include "crypto/evp.h"
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#include "evp_local.h"
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int EVP_CIPHER_CTX_reset(EVP_CIPHER_CTX *c)
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{
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if (c == NULL)
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return 1;
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if (c->cipher != NULL) {
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if (c->cipher->cleanup && !c->cipher->cleanup(c))
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return 0;
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/* Cleanse cipher context data */
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if (c->cipher_data && c->cipher->ctx_size)
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OPENSSL_cleanse(c->cipher_data, c->cipher->ctx_size);
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}
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OPENSSL_free(c->cipher_data);
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#ifndef OPENSSL_NO_ENGINE
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ENGINE_finish(c->engine);
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#endif
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memset(c, 0, sizeof(*c));
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return 1;
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}
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EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void)
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{
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return OPENSSL_zalloc(sizeof(EVP_CIPHER_CTX));
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}
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void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)
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{
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EVP_CIPHER_CTX_reset(ctx);
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OPENSSL_free(ctx);
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}
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int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
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const unsigned char *key, const unsigned char *iv, int enc)
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{
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if (cipher != NULL)
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EVP_CIPHER_CTX_reset(ctx);
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return EVP_CipherInit_ex(ctx, cipher, NULL, key, iv, enc);
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}
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int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
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ENGINE *impl, const unsigned char *key,
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const unsigned char *iv, int enc)
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{
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if (enc == -1)
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enc = ctx->encrypt;
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else {
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if (enc)
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enc = 1;
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ctx->encrypt = enc;
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}
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#ifndef OPENSSL_NO_ENGINE
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/*
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* Whether it's nice or not, "Inits" can be used on "Final"'d contexts so
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* this context may already have an ENGINE! Try to avoid releasing the
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* previous handle, re-querying for an ENGINE, and having a
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* reinitialisation, when it may all be unnecessary.
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*/
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if (ctx->engine && ctx->cipher
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&& (cipher == NULL || cipher->nid == ctx->cipher->nid))
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goto skip_to_init;
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#endif
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if (cipher) {
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/*
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* Ensure a context left lying around from last time is cleared (the
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* previous check attempted to avoid this if the same ENGINE and
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* EVP_CIPHER could be used).
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*/
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if (ctx->cipher
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#ifndef OPENSSL_NO_ENGINE
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|| ctx->engine
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#endif
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|| ctx->cipher_data) {
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unsigned long flags = ctx->flags;
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EVP_CIPHER_CTX_reset(ctx);
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/* Restore encrypt and flags */
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ctx->encrypt = enc;
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ctx->flags = flags;
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}
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#ifndef OPENSSL_NO_ENGINE
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if (impl) {
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if (!ENGINE_init(impl)) {
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EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
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return 0;
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}
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} else
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/* Ask if an ENGINE is reserved for this job */
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impl = ENGINE_get_cipher_engine(cipher->nid);
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if (impl) {
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/* There's an ENGINE for this job ... (apparently) */
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const EVP_CIPHER *c = ENGINE_get_cipher(impl, cipher->nid);
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if (!c) {
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ENGINE_finish(impl);
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EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
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return 0;
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}
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/* We'll use the ENGINE's private cipher definition */
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cipher = c;
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/*
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* Store the ENGINE functional reference so we know 'cipher' came
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* from an ENGINE and we need to release it when done.
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*/
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ctx->engine = impl;
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} else
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ctx->engine = NULL;
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#endif
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ctx->cipher = cipher;
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if (ctx->cipher->ctx_size) {
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ctx->cipher_data = OPENSSL_zalloc(ctx->cipher->ctx_size);
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if (ctx->cipher_data == NULL) {
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ctx->cipher = NULL;
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EVPerr(EVP_F_EVP_CIPHERINIT_EX, ERR_R_MALLOC_FAILURE);
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return 0;
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}
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} else {
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ctx->cipher_data = NULL;
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}
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ctx->key_len = cipher->key_len;
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/* Preserve wrap enable flag, zero everything else */
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ctx->flags &= EVP_CIPHER_CTX_FLAG_WRAP_ALLOW;
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if (ctx->cipher->flags & EVP_CIPH_CTRL_INIT) {
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if (!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL)) {
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ctx->cipher = NULL;
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EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
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return 0;
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}
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}
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} else if (!ctx->cipher) {
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EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_NO_CIPHER_SET);
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return 0;
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}
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#ifndef OPENSSL_NO_ENGINE
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skip_to_init:
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#endif
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/* we assume block size is a power of 2 in *cryptUpdate */
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OPENSSL_assert(ctx->cipher->block_size == 1
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|| ctx->cipher->block_size == 8
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|| ctx->cipher->block_size == 16);
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if (!(ctx->flags & EVP_CIPHER_CTX_FLAG_WRAP_ALLOW)
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&& EVP_CIPHER_CTX_mode(ctx) == EVP_CIPH_WRAP_MODE) {
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EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_WRAP_MODE_NOT_ALLOWED);
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return 0;
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}
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if (!(EVP_CIPHER_flags(EVP_CIPHER_CTX_cipher(ctx)) & EVP_CIPH_CUSTOM_IV)) {
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switch (EVP_CIPHER_CTX_mode(ctx)) {
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case EVP_CIPH_STREAM_CIPHER:
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case EVP_CIPH_ECB_MODE:
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break;
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case EVP_CIPH_CFB_MODE:
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case EVP_CIPH_OFB_MODE:
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ctx->num = 0;
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/* fall-through */
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case EVP_CIPH_CBC_MODE:
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OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) <=
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(int)sizeof(ctx->iv));
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if (iv)
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memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx));
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memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx));
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break;
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case EVP_CIPH_CTR_MODE:
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ctx->num = 0;
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/* Don't reuse IV for CTR mode */
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if (iv)
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memcpy(ctx->iv, iv, EVP_CIPHER_CTX_iv_length(ctx));
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break;
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default:
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return 0;
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}
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}
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if (key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) {
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if (!ctx->cipher->init(ctx, key, iv, enc))
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return 0;
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}
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ctx->buf_len = 0;
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ctx->final_used = 0;
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ctx->block_mask = ctx->cipher->block_size - 1;
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return 1;
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}
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int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
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const unsigned char *in, int inl)
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{
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if (ctx->encrypt)
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return EVP_EncryptUpdate(ctx, out, outl, in, inl);
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else
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return EVP_DecryptUpdate(ctx, out, outl, in, inl);
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}
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int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
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{
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if (ctx->encrypt)
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return EVP_EncryptFinal_ex(ctx, out, outl);
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else
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return EVP_DecryptFinal_ex(ctx, out, outl);
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}
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int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
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{
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if (ctx->encrypt)
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return EVP_EncryptFinal(ctx, out, outl);
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else
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return EVP_DecryptFinal(ctx, out, outl);
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}
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int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
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const unsigned char *key, const unsigned char *iv)
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{
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return EVP_CipherInit(ctx, cipher, key, iv, 1);
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}
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int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
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ENGINE *impl, const unsigned char *key,
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const unsigned char *iv)
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{
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return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1);
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}
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int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
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const unsigned char *key, const unsigned char *iv)
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{
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return EVP_CipherInit(ctx, cipher, key, iv, 0);
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}
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int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
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ENGINE *impl, const unsigned char *key,
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const unsigned char *iv)
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{
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return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 0);
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}
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/*
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* According to the letter of standard difference between pointers
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* is specified to be valid only within same object. This makes
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* it formally challenging to determine if input and output buffers
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* are not partially overlapping with standard pointer arithmetic.
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*/
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#ifdef PTRDIFF_T
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# undef PTRDIFF_T
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#endif
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#if defined(OPENSSL_SYS_VMS) && __INITIAL_POINTER_SIZE==64
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/*
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* Then we have VMS that distinguishes itself by adhering to
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* sizeof(size_t)==4 even in 64-bit builds, which means that
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* difference between two pointers might be truncated to 32 bits.
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* In the context one can even wonder how comparison for
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* equality is implemented. To be on the safe side we adhere to
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* PTRDIFF_T even for comparison for equality.
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*/
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# define PTRDIFF_T uint64_t
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#else
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# define PTRDIFF_T size_t
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#endif
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int is_partially_overlapping(const void *ptr1, const void *ptr2, size_t len)
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{
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PTRDIFF_T diff = (PTRDIFF_T)ptr1-(PTRDIFF_T)ptr2;
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/*
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* Check for partially overlapping buffers. [Binary logical
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* operations are used instead of boolean to minimize number
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* of conditional branches.]
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*/
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int overlapped = (len > 0) & (diff != 0) & ((diff < (PTRDIFF_T)len) |
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(diff > (0 - (PTRDIFF_T)len)));
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return overlapped;
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}
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static int evp_EncryptDecryptUpdate(EVP_CIPHER_CTX *ctx,
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unsigned char *out, int *outl,
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const unsigned char *in, int inl)
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{
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int i, j, bl;
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size_t cmpl = (size_t)inl;
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if (EVP_CIPHER_CTX_test_flags(ctx, EVP_CIPH_FLAG_LENGTH_BITS))
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cmpl = (cmpl + 7) / 8;
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bl = ctx->cipher->block_size;
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/*
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* CCM mode needs to know about the case where inl == 0 && in == NULL - it
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* means the plaintext/ciphertext length is 0
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*/
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if (inl < 0
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|| (inl == 0
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&& EVP_CIPHER_mode(ctx->cipher) != EVP_CIPH_CCM_MODE)) {
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*outl = 0;
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return inl == 0;
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}
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if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
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/* If block size > 1 then the cipher will have to do this check */
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if (bl == 1 && is_partially_overlapping(out, in, cmpl)) {
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EVPerr(EVP_F_EVP_ENCRYPTDECRYPTUPDATE, EVP_R_PARTIALLY_OVERLAPPING);
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return 0;
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}
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i = ctx->cipher->do_cipher(ctx, out, in, inl);
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if (i < 0)
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return 0;
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else
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*outl = i;
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return 1;
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}
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if (is_partially_overlapping(out + ctx->buf_len, in, cmpl)) {
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EVPerr(EVP_F_EVP_ENCRYPTDECRYPTUPDATE, EVP_R_PARTIALLY_OVERLAPPING);
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return 0;
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}
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if (ctx->buf_len == 0 && (inl & (ctx->block_mask)) == 0) {
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if (ctx->cipher->do_cipher(ctx, out, in, inl)) {
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*outl = inl;
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return 1;
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} else {
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*outl = 0;
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return 0;
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}
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}
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i = ctx->buf_len;
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OPENSSL_assert(bl <= (int)sizeof(ctx->buf));
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if (i != 0) {
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if (bl - i > inl) {
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memcpy(&(ctx->buf[i]), in, inl);
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ctx->buf_len += inl;
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*outl = 0;
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return 1;
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} else {
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j = bl - i;
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/*
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* Once we've processed the first j bytes from in, the amount of
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* data left that is a multiple of the block length is:
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* (inl - j) & ~(bl - 1)
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* We must ensure that this amount of data, plus the one block that
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* we process from ctx->buf does not exceed INT_MAX
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*/
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if (((inl - j) & ~(bl - 1)) > INT_MAX - bl) {
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EVPerr(EVP_F_EVP_ENCRYPTDECRYPTUPDATE,
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EVP_R_OUTPUT_WOULD_OVERFLOW);
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return 0;
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}
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memcpy(&(ctx->buf[i]), in, j);
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inl -= j;
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in += j;
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if (!ctx->cipher->do_cipher(ctx, out, ctx->buf, bl))
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return 0;
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out += bl;
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*outl = bl;
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}
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} else
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*outl = 0;
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i = inl & (bl - 1);
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inl -= i;
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if (inl > 0) {
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if (!ctx->cipher->do_cipher(ctx, out, in, inl))
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return 0;
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*outl += inl;
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}
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if (i != 0)
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memcpy(ctx->buf, &(in[inl]), i);
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ctx->buf_len = i;
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return 1;
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}
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int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
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const unsigned char *in, int inl)
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{
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/* Prevent accidental use of decryption context when encrypting */
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if (!ctx->encrypt) {
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EVPerr(EVP_F_EVP_ENCRYPTUPDATE, EVP_R_INVALID_OPERATION);
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return 0;
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}
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return evp_EncryptDecryptUpdate(ctx, out, outl, in, inl);
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}
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int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
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{
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int ret;
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ret = EVP_EncryptFinal_ex(ctx, out, outl);
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return ret;
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}
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int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
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{
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int n, ret;
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unsigned int i, b, bl;
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/* Prevent accidental use of decryption context when encrypting */
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if (!ctx->encrypt) {
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EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX, EVP_R_INVALID_OPERATION);
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return 0;
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}
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if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
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ret = ctx->cipher->do_cipher(ctx, out, NULL, 0);
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if (ret < 0)
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return 0;
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else
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*outl = ret;
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return 1;
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}
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b = ctx->cipher->block_size;
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OPENSSL_assert(b <= sizeof(ctx->buf));
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if (b == 1) {
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*outl = 0;
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return 1;
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}
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bl = ctx->buf_len;
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if (ctx->flags & EVP_CIPH_NO_PADDING) {
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if (bl) {
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EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX,
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EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
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return 0;
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}
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*outl = 0;
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return 1;
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}
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n = b - bl;
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for (i = bl; i < b; i++)
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ctx->buf[i] = n;
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ret = ctx->cipher->do_cipher(ctx, out, ctx->buf, b);
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if (ret)
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*outl = b;
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return ret;
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}
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int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
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const unsigned char *in, int inl)
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{
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int fix_len;
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unsigned int b;
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size_t cmpl = (size_t)inl;
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/* Prevent accidental use of encryption context when decrypting */
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if (ctx->encrypt) {
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EVPerr(EVP_F_EVP_DECRYPTUPDATE, EVP_R_INVALID_OPERATION);
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return 0;
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}
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b = ctx->cipher->block_size;
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if (EVP_CIPHER_CTX_test_flags(ctx, EVP_CIPH_FLAG_LENGTH_BITS))
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cmpl = (cmpl + 7) / 8;
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/*
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* CCM mode needs to know about the case where inl == 0 - it means the
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* plaintext/ciphertext length is 0
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*/
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if (inl < 0
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|| (inl == 0
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&& EVP_CIPHER_mode(ctx->cipher) != EVP_CIPH_CCM_MODE)) {
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*outl = 0;
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return inl == 0;
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}
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if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
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if (b == 1 && is_partially_overlapping(out, in, cmpl)) {
|
|
EVPerr(EVP_F_EVP_DECRYPTUPDATE, EVP_R_PARTIALLY_OVERLAPPING);
|
|
return 0;
|
|
}
|
|
|
|
fix_len = ctx->cipher->do_cipher(ctx, out, in, inl);
|
|
if (fix_len < 0) {
|
|
*outl = 0;
|
|
return 0;
|
|
} else
|
|
*outl = fix_len;
|
|
return 1;
|
|
}
|
|
|
|
if (ctx->flags & EVP_CIPH_NO_PADDING)
|
|
return evp_EncryptDecryptUpdate(ctx, out, outl, in, inl);
|
|
|
|
OPENSSL_assert(b <= sizeof(ctx->final));
|
|
|
|
if (ctx->final_used) {
|
|
/* see comment about PTRDIFF_T comparison above */
|
|
if (((PTRDIFF_T)out == (PTRDIFF_T)in)
|
|
|| is_partially_overlapping(out, in, b)) {
|
|
EVPerr(EVP_F_EVP_DECRYPTUPDATE, EVP_R_PARTIALLY_OVERLAPPING);
|
|
return 0;
|
|
}
|
|
/*
|
|
* final_used is only ever set if buf_len is 0. Therefore the maximum
|
|
* length output we will ever see from evp_EncryptDecryptUpdate is
|
|
* the maximum multiple of the block length that is <= inl, or just:
|
|
* inl & ~(b - 1)
|
|
* Since final_used has been set then the final output length is:
|
|
* (inl & ~(b - 1)) + b
|
|
* This must never exceed INT_MAX
|
|
*/
|
|
if ((inl & ~(b - 1)) > INT_MAX - b) {
|
|
EVPerr(EVP_F_EVP_DECRYPTUPDATE, EVP_R_OUTPUT_WOULD_OVERFLOW);
|
|
return 0;
|
|
}
|
|
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 = ctx->cipher->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;
|
|
}
|
|
|
|
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_priv_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_reset(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 == NULL) {
|
|
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;
|
|
}
|