| /* Copyright (c) 2014, Google Inc. |
| * |
| * Permission to use, copy, modify, and/or distribute this software for any |
| * purpose with or without fee is hereby granted, provided that the above |
| * copyright notice and this permission notice appear in all copies. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY |
| * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION |
| * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN |
| * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ |
| |
| #include <openssl/aead.h> |
| |
| #include <string.h> |
| |
| #include <openssl/cipher.h> |
| #include <openssl/err.h> |
| |
| #include "internal.h" |
| |
| |
| size_t EVP_AEAD_key_length(const EVP_AEAD *aead) { return aead->key_len; } |
| |
| size_t EVP_AEAD_nonce_length(const EVP_AEAD *aead) { return aead->nonce_len; } |
| |
| size_t EVP_AEAD_max_overhead(const EVP_AEAD *aead) { return aead->overhead; } |
| |
| size_t EVP_AEAD_max_tag_len(const EVP_AEAD *aead) { return aead->max_tag_len; } |
| |
| int EVP_AEAD_CTX_init(EVP_AEAD_CTX *ctx, const EVP_AEAD *aead, |
| const uint8_t *key, size_t key_len, size_t tag_len, |
| ENGINE *impl) { |
| if (!aead->init) { |
| OPENSSL_PUT_ERROR(CIPHER, EVP_AEAD_CTX_init, CIPHER_R_NO_DIRECTION_SET); |
| return 0; |
| } |
| return EVP_AEAD_CTX_init_with_direction(ctx, aead, key, key_len, tag_len, |
| evp_aead_open); |
| } |
| |
| int EVP_AEAD_CTX_init_with_direction(EVP_AEAD_CTX *ctx, const EVP_AEAD *aead, |
| const uint8_t *key, size_t key_len, |
| size_t tag_len, |
| enum evp_aead_direction_t dir) { |
| ctx->aead = aead; |
| if (key_len != aead->key_len) { |
| OPENSSL_PUT_ERROR(CIPHER, EVP_AEAD_CTX_init_with_direction, |
| CIPHER_R_UNSUPPORTED_KEY_SIZE); |
| return 0; |
| } |
| if (aead->init) { |
| return aead->init(ctx, key, key_len, tag_len); |
| } else { |
| return aead->init_with_direction(ctx, key, key_len, tag_len, dir); |
| } |
| } |
| |
| void EVP_AEAD_CTX_cleanup(EVP_AEAD_CTX *ctx) { |
| if (ctx->aead == NULL) { |
| return; |
| } |
| ctx->aead->cleanup(ctx); |
| ctx->aead = NULL; |
| } |
| |
| /* check_alias returns 0 if |out| points within the buffer determined by |in| |
| * and |in_len| and 1 otherwise. |
| * |
| * When processing, there's only an issue if |out| points within in[:in_len] |
| * and isn't equal to |in|. If that's the case then writing the output will |
| * stomp input that hasn't been read yet. |
| * |
| * This function checks for that case. */ |
| static int check_alias(const uint8_t *in, size_t in_len, const uint8_t *out) { |
| if (out <= in) { |
| return 1; |
| } else if (in + in_len <= out) { |
| return 1; |
| } |
| return 0; |
| } |
| |
| int EVP_AEAD_CTX_seal(const EVP_AEAD_CTX *ctx, uint8_t *out, size_t *out_len, |
| size_t max_out_len, const uint8_t *nonce, |
| size_t nonce_len, const uint8_t *in, size_t in_len, |
| const uint8_t *ad, size_t ad_len) { |
| size_t possible_out_len = in_len + ctx->aead->overhead; |
| |
| if (possible_out_len < in_len /* overflow */) { |
| OPENSSL_PUT_ERROR(CIPHER, EVP_AEAD_CTX_seal, CIPHER_R_TOO_LARGE); |
| goto error; |
| } |
| |
| if (!check_alias(in, in_len, out)) { |
| OPENSSL_PUT_ERROR(CIPHER, EVP_AEAD_CTX_seal, CIPHER_R_OUTPUT_ALIASES_INPUT); |
| goto error; |
| } |
| |
| if (ctx->aead->seal(ctx, out, out_len, max_out_len, nonce, nonce_len, in, |
| in_len, ad, ad_len)) { |
| return 1; |
| } |
| |
| error: |
| /* In the event of an error, clear the output buffer so that a caller |
| * that doesn't check the return value doesn't send raw data. */ |
| memset(out, 0, max_out_len); |
| *out_len = 0; |
| return 0; |
| } |
| |
| int EVP_AEAD_CTX_open(const EVP_AEAD_CTX *ctx, uint8_t *out, size_t *out_len, |
| size_t max_out_len, const uint8_t *nonce, |
| size_t nonce_len, const uint8_t *in, size_t in_len, |
| const uint8_t *ad, size_t ad_len) { |
| if (!check_alias(in, in_len, out)) { |
| OPENSSL_PUT_ERROR(CIPHER, EVP_AEAD_CTX_open, CIPHER_R_OUTPUT_ALIASES_INPUT); |
| goto error; |
| } |
| |
| if (ctx->aead->open(ctx, out, out_len, max_out_len, nonce, nonce_len, in, |
| in_len, ad, ad_len)) { |
| return 1; |
| } |
| |
| error: |
| /* In the event of an error, clear the output buffer so that a caller |
| * that doesn't check the return value doesn't try and process bad |
| * data. */ |
| memset(out, 0, max_out_len); |
| *out_len = 0; |
| return 0; |
| } |
| |
| int EVP_AEAD_CTX_get_rc4_state(const EVP_AEAD_CTX *ctx, const RC4_KEY **out_key) { |
| if (ctx->aead->get_rc4_state == NULL) { |
| return 0; |
| } |
| |
| return ctx->aead->get_rc4_state(ctx, out_key); |
| } |