/* * aes_gcm_ossl.c * * AES Galois Counter Mode * * John A. Foley * Cisco Systems, Inc. * */ /* * * Copyright (c) 2013, Cisco Systems, Inc. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 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. * * Neither the name of the Cisco Systems, Inc. nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "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 * COPYRIGHT HOLDERS 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. * */ #include #include "aes_icm_ossl.h" #include "aes_gcm_ossl.h" #include "alloc.h" #include "crypto_types.h" debug_module_t mod_aes_gcm = { 0, /* debugging is off by default */ "aes gcm" /* printable module name */ }; /* * The following are the global singleton instances for the * 128-bit and 256-bit GCM ciphers. */ extern cipher_type_t aes_gcm_128_openssl; extern cipher_type_t aes_gcm_256_openssl; /* * For now we only support 8 and 16 octet tags. The spec allows for * optional 12 byte tag, which may be supported in the future. */ #define GCM_AUTH_TAG_LEN 16 #define GCM_AUTH_TAG_LEN_8 8 /* * This function allocates a new instance of this crypto engine. * The key_len parameter should be one of 28 or 44 for * AES-128-GCM or AES-256-GCM respectively. Note that the * key length includes the 14 byte salt value that is used when * initializing the KDF. */ err_status_t aes_gcm_openssl_alloc (cipher_t **c, int key_len, int tlen) { aes_gcm_ctx_t *gcm; int tmp; uint8_t *allptr; debug_print(mod_aes_gcm, "allocating cipher with key length %d", key_len); debug_print(mod_aes_gcm, "allocating cipher with tag length %d", tlen); /* * Verify the key_len is valid for one of: AES-128/256 */ if (key_len != AES_128_GCM_KEYSIZE_WSALT && key_len != AES_256_GCM_KEYSIZE_WSALT) { return (err_status_bad_param); } if (tlen != GCM_AUTH_TAG_LEN && tlen != GCM_AUTH_TAG_LEN_8) { return (err_status_bad_param); } /* allocate memory a cipher of type aes_gcm */ tmp = sizeof(cipher_t) + sizeof(aes_gcm_ctx_t); allptr = crypto_alloc(tmp); if (allptr == NULL) { return (err_status_alloc_fail); } /* set pointers */ *c = (cipher_t*)allptr; (*c)->state = allptr + sizeof(cipher_t); gcm = (aes_gcm_ctx_t *)(*c)->state; /* increment ref_count */ switch (key_len) { case AES_128_GCM_KEYSIZE_WSALT: (*c)->type = &aes_gcm_128_openssl; (*c)->algorithm = AES_128_GCM; aes_gcm_128_openssl.ref_count++; ((aes_gcm_ctx_t*)(*c)->state)->key_size = AES_128_KEYSIZE; ((aes_gcm_ctx_t*)(*c)->state)->tag_len = tlen; break; case AES_256_GCM_KEYSIZE_WSALT: (*c)->type = &aes_gcm_256_openssl; (*c)->algorithm = AES_256_GCM; aes_gcm_256_openssl.ref_count++; ((aes_gcm_ctx_t*)(*c)->state)->key_size = AES_256_KEYSIZE; ((aes_gcm_ctx_t*)(*c)->state)->tag_len = tlen; break; } /* set key size */ (*c)->key_len = key_len; EVP_CIPHER_CTX_init(&gcm->ctx); return (err_status_ok); } /* * This function deallocates a GCM session */ err_status_t aes_gcm_openssl_dealloc (cipher_t *c) { aes_gcm_ctx_t *ctx; ctx = (aes_gcm_ctx_t*)c->state; if (ctx) { EVP_CIPHER_CTX_cleanup(&ctx->ctx); /* decrement ref_count for the appropriate engine */ switch (ctx->key_size) { case AES_256_KEYSIZE: aes_gcm_256_openssl.ref_count--; break; case AES_128_KEYSIZE: aes_gcm_128_openssl.ref_count--; break; default: return (err_status_dealloc_fail); break; } } /* zeroize entire state*/ octet_string_set_to_zero((uint8_t*)c, sizeof(cipher_t) + sizeof(aes_gcm_ctx_t)); /* free memory */ crypto_free(c); return (err_status_ok); } /* * aes_gcm_openssl_context_init(...) initializes the aes_gcm_context * using the value in key[]. * * the key is the secret key */ err_status_t aes_gcm_openssl_context_init (aes_gcm_ctx_t *c, const uint8_t *key) { c->dir = direction_any; /* copy key to be used later when CiscoSSL crypto context is created */ v128_copy_octet_string((v128_t*)&c->key, key); if (c->key_size == AES_256_KEYSIZE) { debug_print(mod_aes_gcm, "Copying last 16 bytes of key: %s", v128_hex_string((v128_t*)(key + AES_128_KEYSIZE))); v128_copy_octet_string(((v128_t*)(&c->key.v8)) + 1, key + AES_128_KEYSIZE); } debug_print(mod_aes_gcm, "key: %s", v128_hex_string((v128_t*)&c->key)); EVP_CIPHER_CTX_cleanup(&c->ctx); return (err_status_ok); } /* * aes_gcm_openssl_set_iv(c, iv) sets the counter value to the exor of iv with * the offset */ err_status_t aes_gcm_openssl_set_iv (aes_gcm_ctx_t *c, void *iv, int direction) { const EVP_CIPHER *evp; v128_t *nonce = iv; if (direction != direction_encrypt && direction != direction_decrypt) { return (err_status_bad_param); } c->dir = direction; debug_print(mod_aes_gcm, "setting iv: %s", v128_hex_string(nonce)); switch (c->key_size) { case AES_256_KEYSIZE: evp = EVP_aes_256_gcm(); break; case AES_128_KEYSIZE: evp = EVP_aes_128_gcm(); break; default: return (err_status_bad_param); break; } if (!EVP_CipherInit_ex(&c->ctx, evp, NULL, (const unsigned char*)&c->key.v8, NULL, (c->dir == direction_encrypt ? 1 : 0))) { return (err_status_init_fail); } /* set IV len and the IV value, the followiong 3 calls are required */ if (!EVP_CIPHER_CTX_ctrl(&c->ctx, EVP_CTRL_GCM_SET_IVLEN, 12, 0)) { return (err_status_init_fail); } if (!EVP_CIPHER_CTX_ctrl(&c->ctx, EVP_CTRL_GCM_SET_IV_FIXED, -1, iv)) { return (err_status_init_fail); } if (!EVP_CIPHER_CTX_ctrl(&c->ctx, EVP_CTRL_GCM_IV_GEN, 0, iv)) { return (err_status_init_fail); } return (err_status_ok); } /* * This function processes the AAD * * Parameters: * c Crypto context * aad Additional data to process for AEAD cipher suites * aad_len length of aad buffer */ err_status_t aes_gcm_openssl_set_aad (aes_gcm_ctx_t *c, unsigned char *aad, unsigned int aad_len) { int rv; /* * Set dummy tag, OpenSSL requires the Tag to be set before * processing AAD */ EVP_CIPHER_CTX_ctrl(&c->ctx, EVP_CTRL_GCM_SET_TAG, c->tag_len, aad); rv = EVP_Cipher(&c->ctx, NULL, aad, aad_len); if (rv != aad_len) { return (err_status_algo_fail); } else { return (err_status_ok); } } /* * This function encrypts a buffer using AES GCM mode * * Parameters: * c Crypto context * buf data to encrypt * enc_len length of encrypt buffer */ err_status_t aes_gcm_openssl_encrypt (aes_gcm_ctx_t *c, unsigned char *buf, unsigned int *enc_len) { if (c->dir != direction_encrypt && c->dir != direction_decrypt) { return (err_status_bad_param); } /* * Encrypt the data */ EVP_Cipher(&c->ctx, buf, buf, *enc_len); return (err_status_ok); } /* * This function calculates and returns the GCM tag for a given context. * This should be called after encrypting the data. The *len value * is increased by the tag size. The caller must ensure that *buf has * enough room to accept the appended tag. * * Parameters: * c Crypto context * buf data to encrypt * len length of encrypt buffer */ err_status_t aes_gcm_openssl_get_tag (aes_gcm_ctx_t *c, unsigned char *buf, int *len) { /* * Calculate the tag */ EVP_Cipher(&c->ctx, NULL, NULL, 0); /* * Retreive the tag */ EVP_CIPHER_CTX_ctrl(&c->ctx, EVP_CTRL_GCM_GET_TAG, c->tag_len, buf); /* * Increase encryption length by desired tag size */ *len = c->tag_len; return (err_status_ok); } /* * This function decrypts a buffer using AES GCM mode * * Parameters: * c Crypto context * buf data to encrypt * enc_len length of encrypt buffer */ err_status_t aes_gcm_openssl_decrypt (aes_gcm_ctx_t *c, unsigned char *buf, unsigned int *enc_len) { if (c->dir != direction_encrypt && c->dir != direction_decrypt) { return (err_status_bad_param); } /* * Set the tag before decrypting */ EVP_CIPHER_CTX_ctrl(&c->ctx, EVP_CTRL_GCM_SET_TAG, c->tag_len, buf + (*enc_len - c->tag_len)); EVP_Cipher(&c->ctx, buf, buf, *enc_len - c->tag_len); /* * Check the tag */ if (EVP_Cipher(&c->ctx, NULL, NULL, 0)) { return (err_status_auth_fail); } /* * Reduce the buffer size by the tag length since the tag * is not part of the original payload */ *enc_len -= c->tag_len; return (err_status_ok); } /* * Name of this crypto engine */ char aes_gcm_128_openssl_description[] = "AES-128 GCM using openssl"; char aes_gcm_256_openssl_description[] = "AES-256 GCM using openssl"; /* * KAT values for AES self-test. These * values we're derived from independent test code * using OpenSSL. */ uint8_t aes_gcm_test_case_0_key[AES_128_GCM_KEYSIZE_WSALT] = { 0xfe, 0xff, 0xe9, 0x92, 0x86, 0x65, 0x73, 0x1c, 0x6d, 0x6a, 0x8f, 0x94, 0x67, 0x30, 0x83, 0x08, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, }; uint8_t aes_gcm_test_case_0_iv[12] = { 0xca, 0xfe, 0xba, 0xbe, 0xfa, 0xce, 0xdb, 0xad, 0xde, 0xca, 0xf8, 0x88 }; uint8_t aes_gcm_test_case_0_plaintext[60] = { 0xd9, 0x31, 0x32, 0x25, 0xf8, 0x84, 0x06, 0xe5, 0xa5, 0x59, 0x09, 0xc5, 0xaf, 0xf5, 0x26, 0x9a, 0x86, 0xa7, 0xa9, 0x53, 0x15, 0x34, 0xf7, 0xda, 0x2e, 0x4c, 0x30, 0x3d, 0x8a, 0x31, 0x8a, 0x72, 0x1c, 0x3c, 0x0c, 0x95, 0x95, 0x68, 0x09, 0x53, 0x2f, 0xcf, 0x0e, 0x24, 0x49, 0xa6, 0xb5, 0x25, 0xb1, 0x6a, 0xed, 0xf5, 0xaa, 0x0d, 0xe6, 0x57, 0xba, 0x63, 0x7b, 0x39 }; uint8_t aes_gcm_test_case_0_aad[20] = { 0xfe, 0xed, 0xfa, 0xce, 0xde, 0xad, 0xbe, 0xef, 0xfe, 0xed, 0xfa, 0xce, 0xde, 0xad, 0xbe, 0xef, 0xab, 0xad, 0xda, 0xd2 }; uint8_t aes_gcm_test_case_0_ciphertext[76] = { 0x42, 0x83, 0x1e, 0xc2, 0x21, 0x77, 0x74, 0x24, 0x4b, 0x72, 0x21, 0xb7, 0x84, 0xd0, 0xd4, 0x9c, 0xe3, 0xaa, 0x21, 0x2f, 0x2c, 0x02, 0xa4, 0xe0, 0x35, 0xc1, 0x7e, 0x23, 0x29, 0xac, 0xa1, 0x2e, 0x21, 0xd5, 0x14, 0xb2, 0x54, 0x66, 0x93, 0x1c, 0x7d, 0x8f, 0x6a, 0x5a, 0xac, 0x84, 0xaa, 0x05, 0x1b, 0xa3, 0x0b, 0x39, 0x6a, 0x0a, 0xac, 0x97, 0x3d, 0x58, 0xe0, 0x91, /* the last 16 bytes are the tag */ 0x5b, 0xc9, 0x4f, 0xbc, 0x32, 0x21, 0xa5, 0xdb, 0x94, 0xfa, 0xe9, 0x5a, 0xe7, 0x12, 0x1a, 0x47, }; cipher_test_case_t aes_gcm_test_case_0a = { AES_128_GCM_KEYSIZE_WSALT, /* octets in key */ aes_gcm_test_case_0_key, /* key */ aes_gcm_test_case_0_iv, /* packet index */ 60, /* octets in plaintext */ aes_gcm_test_case_0_plaintext, /* plaintext */ 68, /* octets in ciphertext */ aes_gcm_test_case_0_ciphertext, /* ciphertext + tag */ 20, /* octets in AAD */ aes_gcm_test_case_0_aad, /* AAD */ GCM_AUTH_TAG_LEN_8, NULL /* pointer to next testcase */ }; cipher_test_case_t aes_gcm_test_case_0 = { AES_128_GCM_KEYSIZE_WSALT, /* octets in key */ aes_gcm_test_case_0_key, /* key */ aes_gcm_test_case_0_iv, /* packet index */ 60, /* octets in plaintext */ aes_gcm_test_case_0_plaintext, /* plaintext */ 76, /* octets in ciphertext */ aes_gcm_test_case_0_ciphertext, /* ciphertext + tag */ 20, /* octets in AAD */ aes_gcm_test_case_0_aad, /* AAD */ GCM_AUTH_TAG_LEN, &aes_gcm_test_case_0a /* pointer to next testcase */ }; uint8_t aes_gcm_test_case_1_key[AES_256_GCM_KEYSIZE_WSALT] = { 0xfe, 0xff, 0xe9, 0x92, 0x86, 0x65, 0x73, 0x1c, 0xa5, 0x59, 0x09, 0xc5, 0x54, 0x66, 0x93, 0x1c, 0xaf, 0xf5, 0x26, 0x9a, 0x21, 0xd5, 0x14, 0xb2, 0x6d, 0x6a, 0x8f, 0x94, 0x67, 0x30, 0x83, 0x08, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, }; uint8_t aes_gcm_test_case_1_iv[12] = { 0xca, 0xfe, 0xba, 0xbe, 0xfa, 0xce, 0xdb, 0xad, 0xde, 0xca, 0xf8, 0x88 }; uint8_t aes_gcm_test_case_1_plaintext[60] = { 0xd9, 0x31, 0x32, 0x25, 0xf8, 0x84, 0x06, 0xe5, 0xa5, 0x59, 0x09, 0xc5, 0xaf, 0xf5, 0x26, 0x9a, 0x86, 0xa7, 0xa9, 0x53, 0x15, 0x34, 0xf7, 0xda, 0x2e, 0x4c, 0x30, 0x3d, 0x8a, 0x31, 0x8a, 0x72, 0x1c, 0x3c, 0x0c, 0x95, 0x95, 0x68, 0x09, 0x53, 0x2f, 0xcf, 0x0e, 0x24, 0x49, 0xa6, 0xb5, 0x25, 0xb1, 0x6a, 0xed, 0xf5, 0xaa, 0x0d, 0xe6, 0x57, 0xba, 0x63, 0x7b, 0x39 }; uint8_t aes_gcm_test_case_1_aad[20] = { 0xfe, 0xed, 0xfa, 0xce, 0xde, 0xad, 0xbe, 0xef, 0xfe, 0xed, 0xfa, 0xce, 0xde, 0xad, 0xbe, 0xef, 0xab, 0xad, 0xda, 0xd2 }; uint8_t aes_gcm_test_case_1_ciphertext[76] = { 0x0b, 0x11, 0xcf, 0xaf, 0x68, 0x4d, 0xae, 0x46, 0xc7, 0x90, 0xb8, 0x8e, 0xb7, 0x6a, 0x76, 0x2a, 0x94, 0x82, 0xca, 0xab, 0x3e, 0x39, 0xd7, 0x86, 0x1b, 0xc7, 0x93, 0xed, 0x75, 0x7f, 0x23, 0x5a, 0xda, 0xfd, 0xd3, 0xe2, 0x0e, 0x80, 0x87, 0xa9, 0x6d, 0xd7, 0xe2, 0x6a, 0x7d, 0x5f, 0xb4, 0x80, 0xef, 0xef, 0xc5, 0x29, 0x12, 0xd1, 0xaa, 0x10, 0x09, 0xc9, 0x86, 0xc1, /* the last 16 bytes are the tag */ 0x45, 0xbc, 0x03, 0xe6, 0xe1, 0xac, 0x0a, 0x9f, 0x81, 0xcb, 0x8e, 0x5b, 0x46, 0x65, 0x63, 0x1d, }; cipher_test_case_t aes_gcm_test_case_1a = { AES_256_GCM_KEYSIZE_WSALT, /* octets in key */ aes_gcm_test_case_1_key, /* key */ aes_gcm_test_case_1_iv, /* packet index */ 60, /* octets in plaintext */ aes_gcm_test_case_1_plaintext, /* plaintext */ 68, /* octets in ciphertext */ aes_gcm_test_case_1_ciphertext, /* ciphertext + tag */ 20, /* octets in AAD */ aes_gcm_test_case_1_aad, /* AAD */ GCM_AUTH_TAG_LEN_8, NULL /* pointer to next testcase */ }; cipher_test_case_t aes_gcm_test_case_1 = { AES_256_GCM_KEYSIZE_WSALT, /* octets in key */ aes_gcm_test_case_1_key, /* key */ aes_gcm_test_case_1_iv, /* packet index */ 60, /* octets in plaintext */ aes_gcm_test_case_1_plaintext, /* plaintext */ 76, /* octets in ciphertext */ aes_gcm_test_case_1_ciphertext, /* ciphertext + tag */ 20, /* octets in AAD */ aes_gcm_test_case_1_aad, /* AAD */ GCM_AUTH_TAG_LEN, &aes_gcm_test_case_1a /* pointer to next testcase */ }; /* * This is the vector function table for this crypto engine. */ cipher_type_t aes_gcm_128_openssl = { (cipher_alloc_func_t) aes_gcm_openssl_alloc, (cipher_dealloc_func_t) aes_gcm_openssl_dealloc, (cipher_init_func_t) aes_gcm_openssl_context_init, (cipher_set_aad_func_t) aes_gcm_openssl_set_aad, (cipher_encrypt_func_t) aes_gcm_openssl_encrypt, (cipher_decrypt_func_t) aes_gcm_openssl_decrypt, (cipher_set_iv_func_t) aes_gcm_openssl_set_iv, (cipher_get_tag_func_t) aes_gcm_openssl_get_tag, (char*) aes_gcm_128_openssl_description, (int) 0, /* instance count */ (cipher_test_case_t*) &aes_gcm_test_case_0, (debug_module_t*) &mod_aes_gcm, (cipher_type_id_t) AES_128_GCM }; /* * This is the vector function table for this crypto engine. */ cipher_type_t aes_gcm_256_openssl = { (cipher_alloc_func_t) aes_gcm_openssl_alloc, (cipher_dealloc_func_t) aes_gcm_openssl_dealloc, (cipher_init_func_t) aes_gcm_openssl_context_init, (cipher_set_aad_func_t) aes_gcm_openssl_set_aad, (cipher_encrypt_func_t) aes_gcm_openssl_encrypt, (cipher_decrypt_func_t) aes_gcm_openssl_decrypt, (cipher_set_iv_func_t) aes_gcm_openssl_set_iv, (cipher_get_tag_func_t) aes_gcm_openssl_get_tag, (char*) aes_gcm_256_openssl_description, (int) 0, /* instance count */ (cipher_test_case_t*) &aes_gcm_test_case_1, (debug_module_t*) &mod_aes_gcm, (cipher_type_id_t) AES_256_GCM };