+From 2887a5c8f9a385b3ebee12b98f68e7d1f9cc0ea0 Mon Sep 17 00:00:00 2001
+From: Eneas U de Queiroz <cote2004-github@yahoo.com>
+Date: Wed, 28 Nov 2018 11:26:27 -0200
+Subject: [PATCH 6/7] eng_devcrypto: fix ctr mode
+
+Make CTR mode behave like a stream cipher.
+
+Signed-off-by: Eneas U de Queiroz <cote2004-github@yahoo.com>
+
+Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
+Reviewed-by: Richard Levitte <levitte@openssl.org>
+(Merged from https://github.com/openssl/openssl/pull/7585)
+
+(cherry picked from commit b5015e834aa7d3f0a5d7585a8fae05cecbdbb848)
+
+--- a/crypto/engine/eng_devcrypto.c
++++ b/crypto/engine/eng_devcrypto.c
+@@ -47,10 +47,12 @@ static int cfd;
+
+ struct cipher_ctx {
+ struct session_op sess;
+-
+- /* to pass from init to do_cipher */
+- const unsigned char *iv;
+ int op; /* COP_ENCRYPT or COP_DECRYPT */
++ unsigned long mode; /* EVP_CIPH_*_MODE */
++
++ /* to handle ctr mode being a stream cipher */
++ unsigned char partial[EVP_MAX_BLOCK_LENGTH];
++ unsigned int blocksize, num;
+ };
+
+ static const struct cipher_data_st {
+@@ -87,9 +89,9 @@ static const struct cipher_data_st {
+ { NID_aes_256_xts, 16, 256 / 8 * 2, 16, EVP_CIPH_XTS_MODE, CRYPTO_AES_XTS },
+ #endif
+ #if !defined(CHECK_BSD_STYLE_MACROS) || defined(CRYPTO_AES_ECB)
+- { NID_aes_128_ecb, 16, 128 / 8, 16, EVP_CIPH_ECB_MODE, CRYPTO_AES_ECB },
+- { NID_aes_192_ecb, 16, 192 / 8, 16, EVP_CIPH_ECB_MODE, CRYPTO_AES_ECB },
+- { NID_aes_256_ecb, 16, 256 / 8, 16, EVP_CIPH_ECB_MODE, CRYPTO_AES_ECB },
++ { NID_aes_128_ecb, 16, 128 / 8, 0, EVP_CIPH_ECB_MODE, CRYPTO_AES_ECB },
++ { NID_aes_192_ecb, 16, 192 / 8, 0, EVP_CIPH_ECB_MODE, CRYPTO_AES_ECB },
++ { NID_aes_256_ecb, 16, 256 / 8, 0, EVP_CIPH_ECB_MODE, CRYPTO_AES_ECB },
+ #endif
+ #if 0 /* Not yet supported */
+ { NID_aes_128_gcm, 16, 128 / 8, 16, EVP_CIPH_GCM_MODE, CRYPTO_AES_GCM },
+@@ -146,6 +148,8 @@ static int cipher_init(EVP_CIPHER_CTX *c
+ cipher_ctx->sess.keylen = cipher_d->keylen;
+ cipher_ctx->sess.key = (void *)key;
+ cipher_ctx->op = enc ? COP_ENCRYPT : COP_DECRYPT;
++ cipher_ctx->mode = cipher_d->flags & EVP_CIPH_MODE;
++ cipher_ctx->blocksize = cipher_d->blocksize;
+ if (ioctl(cfd, CIOCGSESSION, &cipher_ctx->sess) < 0) {
+ SYSerr(SYS_F_IOCTL, errno);
+ return 0;
+@@ -160,8 +164,11 @@ static int cipher_do_cipher(EVP_CIPHER_C
+ struct cipher_ctx *cipher_ctx =
+ (struct cipher_ctx *)EVP_CIPHER_CTX_get_cipher_data(ctx);
+ struct crypt_op cryp;
++ unsigned char *iv = EVP_CIPHER_CTX_iv_noconst(ctx);
+ #if !defined(COP_FLAG_WRITE_IV)
+ unsigned char saved_iv[EVP_MAX_IV_LENGTH];
++ const unsigned char *ivptr;
++ size_t nblocks, ivlen;
+ #endif
+
+ memset(&cryp, 0, sizeof(cryp));
+@@ -169,19 +176,28 @@ static int cipher_do_cipher(EVP_CIPHER_C
+ cryp.len = inl;
+ cryp.src = (void *)in;
+ cryp.dst = (void *)out;
+- cryp.iv = (void *)EVP_CIPHER_CTX_iv_noconst(ctx);
++ cryp.iv = (void *)iv;
+ cryp.op = cipher_ctx->op;
+ #if !defined(COP_FLAG_WRITE_IV)
+ cryp.flags = 0;
+
+- if (EVP_CIPHER_CTX_iv_length(ctx) > 0) {
+- assert(inl >= EVP_CIPHER_CTX_iv_length(ctx));
+- if (!EVP_CIPHER_CTX_encrypting(ctx)) {
+- unsigned char *ivptr = in + inl - EVP_CIPHER_CTX_iv_length(ctx);
++ ivlen = EVP_CIPHER_CTX_iv_length(ctx);
++ if (ivlen > 0)
++ switch (cipher_ctx->mode) {
++ case EVP_CIPH_CBC_MODE:
++ assert(inl >= ivlen);
++ if (!EVP_CIPHER_CTX_encrypting(ctx)) {
++ ivptr = in + inl - ivlen;
++ memcpy(saved_iv, ivptr, ivlen);
++ }
++ break;
++
++ case EVP_CIPH_CTR_MODE:
++ break;
+
+- memcpy(saved_iv, ivptr, EVP_CIPHER_CTX_iv_length(ctx));
++ default: /* should not happen */
++ return 0;
+ }
+- }
+ #else
+ cryp.flags = COP_FLAG_WRITE_IV;
+ #endif
+@@ -192,17 +208,74 @@ static int cipher_do_cipher(EVP_CIPHER_C
+ }
+
+ #if !defined(COP_FLAG_WRITE_IV)
+- if (EVP_CIPHER_CTX_iv_length(ctx) > 0) {
+- unsigned char *ivptr = saved_iv;
++ if (ivlen > 0)
++ switch (cipher_ctx->mode) {
++ case EVP_CIPH_CBC_MODE:
++ assert(inl >= ivlen);
++ if (EVP_CIPHER_CTX_encrypting(ctx))
++ ivptr = out + inl - ivlen;
++ else
++ ivptr = saved_iv;
++
++ memcpy(iv, ivptr, ivlen);
++ break;
++
++ case EVP_CIPH_CTR_MODE:
++ nblocks = (inl + cipher_ctx->blocksize - 1)
++ / cipher_ctx->blocksize;
++ do {
++ ivlen--;
++ nblocks += iv[ivlen];
++ iv[ivlen] = (uint8_t) nblocks;
++ nblocks >>= 8;
++ } while (ivlen);
++ break;
++
++ default: /* should not happen */
++ return 0;
++ }
++#endif
++
++ return 1;
++}
+
+- assert(inl >= EVP_CIPHER_CTX_iv_length(ctx));
+- if (!EVP_CIPHER_CTX_encrypting(ctx))
+- ivptr = out + inl - EVP_CIPHER_CTX_iv_length(ctx);
++static int ctr_do_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
++ const unsigned char *in, size_t inl)
++{
++ struct cipher_ctx *cipher_ctx =
++ (struct cipher_ctx *)EVP_CIPHER_CTX_get_cipher_data(ctx);
++ size_t nblocks, len;
+
+- memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), ivptr,
+- EVP_CIPHER_CTX_iv_length(ctx));
++ /* initial partial block */
++ while (cipher_ctx->num && inl) {
++ (*out++) = *(in++) ^ cipher_ctx->partial[cipher_ctx->num];
++ --inl;
++ cipher_ctx->num = (cipher_ctx->num + 1) % cipher_ctx->blocksize;
++ }
++
++ /* full blocks */
++ if (inl > (unsigned int) cipher_ctx->blocksize) {
++ nblocks = inl/cipher_ctx->blocksize;
++ len = nblocks * cipher_ctx->blocksize;
++ if (cipher_do_cipher(ctx, out, in, len) < 1)
++ return 0;
++ inl -= len;
++ out += len;
++ in += len;
++ }
++
++ /* final partial block */
++ if (inl) {
++ memset(cipher_ctx->partial, 0, cipher_ctx->blocksize);
++ if (cipher_do_cipher(ctx, cipher_ctx->partial, cipher_ctx->partial,
++ cipher_ctx->blocksize) < 1)
++ return 0;
++ while (inl--) {
++ out[cipher_ctx->num] = in[cipher_ctx->num]
++ ^ cipher_ctx->partial[cipher_ctx->num];
++ cipher_ctx->num++;
++ }
+ }
+-#endif
+
+ return 1;
+ }
+@@ -249,6 +322,7 @@ static void prepare_cipher_methods(void)
+ {
+ size_t i;
+ struct session_op sess;
++ unsigned long cipher_mode;
+
+ memset(&sess, 0, sizeof(sess));
+ sess.key = (void *)"01234567890123456789012345678901234567890123456789";
+@@ -266,9 +340,12 @@ static void prepare_cipher_methods(void)
+ || ioctl(cfd, CIOCFSESSION, &sess.ses) < 0)
+ continue;
+
++ cipher_mode = cipher_data[i].flags & EVP_CIPH_MODE;
++
+ if ((known_cipher_methods[i] =
+ EVP_CIPHER_meth_new(cipher_data[i].nid,
+- cipher_data[i].blocksize,
++ cipher_mode == EVP_CIPH_CTR_MODE ? 1 :
++ cipher_data[i].blocksize,
+ cipher_data[i].keylen)) == NULL
+ || !EVP_CIPHER_meth_set_iv_length(known_cipher_methods[i],
+ cipher_data[i].ivlen)
+@@ -278,6 +355,8 @@ static void prepare_cipher_methods(void)
+ | EVP_CIPH_FLAG_DEFAULT_ASN1)
+ || !EVP_CIPHER_meth_set_init(known_cipher_methods[i], cipher_init)
+ || !EVP_CIPHER_meth_set_do_cipher(known_cipher_methods[i],
++ cipher_mode == EVP_CIPH_CTR_MODE ?
++ ctr_do_cipher :
+ cipher_do_cipher)
+ || !EVP_CIPHER_meth_set_ctrl(known_cipher_methods[i], cipher_ctrl)
+ || !EVP_CIPHER_meth_set_cleanup(known_cipher_methods[i],
projects / openwrt / openwrt.git / commitdiff