static int aes_gcm_init_key(EVP_CIPHER_CTX *ctx, const uint8_t *key,
const uint8_t *iv, int enc) {
EVP_AES_GCM_CTX *gctx = ctx->cipher_data;
if (!iv && !key) {
return 1;
}
if (key) {
OPENSSL_memset(&gctx->gcm, 0, sizeof(gctx->gcm));
gctx->ctr = aes_ctr_set_key(&gctx->ks.ks, &gctx->gcm.gcm_key, NULL, key,
ctx->key_len);
// If we have an iv can set it directly, otherwise use saved IV.
if (iv == NULL && gctx->iv_set) {
iv = gctx->iv;
}
if (iv) {
CRYPTO_gcm128_setiv(&gctx->gcm, &gctx->ks.ks, iv, gctx->ivlen);
gctx->iv_set = 1;
}
gctx->key_set = 1;
} else {
// If key set use IV, otherwise copy
if (gctx->key_set) {
CRYPTO_gcm128_setiv(&gctx->gcm, &gctx->ks.ks, iv, gctx->ivlen);
} else {
OPENSSL_memcpy(gctx->iv, iv, gctx->ivlen);
}
gctx->iv_set = 1;
gctx->iv_gen = 0;
}
return 1;
}
static int aead_aes_ctr_hmac_sha256_init(EVP_AEAD_CTX *ctx, const uint8_t *key,
size_t key_len, size_t tag_len) {
struct aead_aes_ctr_hmac_sha256_ctx *aes_ctx =
(struct aead_aes_ctr_hmac_sha256_ctx *)&ctx->state;
static const size_t hmac_key_len = 32;
if (key_len < hmac_key_len) {
OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_BAD_KEY_LENGTH);
return 0; // EVP_AEAD_CTX_init should catch this.
}
const size_t aes_key_len = key_len - hmac_key_len;
if (aes_key_len != 16 && aes_key_len != 32) {
OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_BAD_KEY_LENGTH);
return 0; // EVP_AEAD_CTX_init should catch this.
}
if (tag_len == EVP_AEAD_DEFAULT_TAG_LENGTH) {
tag_len = EVP_AEAD_AES_CTR_HMAC_SHA256_TAG_LEN;
}
if (tag_len > EVP_AEAD_AES_CTR_HMAC_SHA256_TAG_LEN) {
OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_TAG_TOO_LARGE);
return 0;
}
aes_ctx->ctr =
aes_ctr_set_key(&aes_ctx->ks.ks, NULL, &aes_ctx->block, key, aes_key_len);
ctx->tag_len = tag_len;
hmac_init(&aes_ctx->inner_init_state, &aes_ctx->outer_init_state,
key + aes_key_len);
return 1;
}
static int aead_aes_ccm_init(EVP_AEAD_CTX *ctx, const uint8_t *key,
size_t key_len, size_t tag_len, unsigned M,
unsigned L) {
assert(M == EVP_AEAD_max_overhead(ctx->aead));
assert(M == EVP_AEAD_max_tag_len(ctx->aead));
assert(15 - L == EVP_AEAD_nonce_length(ctx->aead));
if (key_len != EVP_AEAD_key_length(ctx->aead)) {
OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_BAD_KEY_LENGTH);
return 0; // EVP_AEAD_CTX_init should catch this.
}
if (tag_len == EVP_AEAD_DEFAULT_TAG_LENGTH) {
tag_len = M;
}
if (tag_len != M) {
OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_TAG_TOO_LARGE);
return 0;
}
struct aead_aes_ccm_ctx *ccm_ctx = (struct aead_aes_ccm_ctx *)&ctx->state;
block128_f block;
ctr128_f ctr = aes_ctr_set_key(&ccm_ctx->ks.ks, NULL, &block, key, key_len);
ctx->tag_len = tag_len;
if (!CRYPTO_ccm128_init(&ccm_ctx->ccm, &ccm_ctx->ks.ks, block, ctr, M, L)) {
OPENSSL_PUT_ERROR(CIPHER, ERR_R_INTERNAL_ERROR);
return 0;
}
return 1;
}
int evp_aead_aes_gcm_init(void *ctx_buf, size_t ctx_buf_len, const uint8_t *key,
size_t key_len) {
aead_assert_init_preconditions(alignof(struct aead_aes_gcm_ctx),
sizeof(struct aead_aes_gcm_ctx), ctx_buf,
ctx_buf_len, key);
struct aead_aes_gcm_ctx *gcm_ctx = ctx_buf;
gcm_ctx->ctr =
aes_ctr_set_key(&gcm_ctx->ks.ks, &gcm_ctx->gcm, NULL, key, key_len);
return 1;
}
static int aead_aes_gcm_init_impl(struct aead_aes_gcm_ctx *gcm_ctx,
size_t *out_tag_len, const uint8_t *key,
size_t key_len, size_t tag_len) {
const size_t key_bits = key_len * 8;
if (key_bits != 128 && key_bits != 256) {
OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_BAD_KEY_LENGTH);
return 0; // EVP_AEAD_CTX_init should catch this.
}
if (tag_len == EVP_AEAD_DEFAULT_TAG_LENGTH) {
tag_len = EVP_AEAD_AES_GCM_TAG_LEN;
}
if (tag_len > EVP_AEAD_AES_GCM_TAG_LEN) {
OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_TAG_TOO_LARGE);
return 0;
}
gcm_ctx->ctr =
aes_ctr_set_key(&gcm_ctx->ks.ks, &gcm_ctx->gcm_key, NULL, key, key_len);
*out_tag_len = tag_len;
return 1;
}
static int aead_aes_ccm_bluetooth_init(EVP_AEAD_CTX *ctx, const uint8_t *key,
size_t key_len, size_t tag_len) {
if (key_len != 16) {
OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_BAD_KEY_LENGTH);
return 0; // EVP_AEAD_CTX_init should catch this.
}
if (tag_len == EVP_AEAD_DEFAULT_TAG_LENGTH) {
tag_len = EVP_AEAD_AES_CCM_BLUETOOTH_TAG_LEN;
}
if (tag_len != EVP_AEAD_AES_CCM_BLUETOOTH_TAG_LEN) {
OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_TAG_TOO_LARGE);
return 0;
}
struct aead_aes_ccm_ctx *ccm_ctx =
OPENSSL_malloc(sizeof(struct aead_aes_ccm_ctx));
if (ccm_ctx == NULL) {
OPENSSL_PUT_ERROR(CIPHER, ERR_R_MALLOC_FAILURE);
return 0;
}
block128_f block;
ctr128_f ctr = aes_ctr_set_key(&ccm_ctx->ks.ks, NULL, &block, key, key_len);
ctx->tag_len = tag_len;
if (!CRYPTO_ccm128_init(&ccm_ctx->ccm, &ccm_ctx->ks.ks, block, ctr, tag_len,
15 - EVP_AEAD_AES_CCM_BLUETOOTH_NONCE_LEN)) {
OPENSSL_PUT_ERROR(CIPHER, ERR_R_INTERNAL_ERROR);
OPENSSL_free(ccm_ctx);
return 0;
}
ctx->aead_state = ccm_ctx;
return 1;
}
