1 /*
2  *
3  * Copyright 2018 gRPC authors.
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  *     http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  *
17  */
18 
19 #include <grpc/support/port_platform.h>
20 
21 #include "src/core/tsi/alts/crypt/gsec.h"
22 
23 #include <stdio.h>
24 #include <string.h>
25 
26 #include <grpc/support/alloc.h>
27 
28 static const char vtable_error_msg[] =
29     "crypter or crypter->vtable has not been initialized properly";
30 
maybe_copy_error_msg(const char * src,char ** dst)31 static void maybe_copy_error_msg(const char* src, char** dst) {
32   if (dst != nullptr && src != nullptr) {
33     *dst = static_cast<char*>(gpr_malloc(strlen(src) + 1));
34     memcpy(*dst, src, strlen(src) + 1);
35   }
36 }
37 
gsec_aead_crypter_encrypt(gsec_aead_crypter * crypter,const uint8_t * nonce,size_t nonce_length,const uint8_t * aad,size_t aad_length,const uint8_t * plaintext,size_t plaintext_length,uint8_t * ciphertext_and_tag,size_t ciphertext_and_tag_length,size_t * bytes_written,char ** error_details)38 grpc_status_code gsec_aead_crypter_encrypt(
39     gsec_aead_crypter* crypter, const uint8_t* nonce, size_t nonce_length,
40     const uint8_t* aad, size_t aad_length, const uint8_t* plaintext,
41     size_t plaintext_length, uint8_t* ciphertext_and_tag,
42     size_t ciphertext_and_tag_length, size_t* bytes_written,
43     char** error_details) {
44   if (crypter != nullptr && crypter->vtable != nullptr &&
45       crypter->vtable->encrypt_iovec != nullptr) {
46     struct iovec aad_vec = {(void*)aad, aad_length};
47     struct iovec plaintext_vec = {(void*)plaintext, plaintext_length};
48     struct iovec ciphertext_vec = {ciphertext_and_tag,
49                                    ciphertext_and_tag_length};
50     return crypter->vtable->encrypt_iovec(
51         crypter, nonce, nonce_length, &aad_vec, 1, &plaintext_vec, 1,
52         ciphertext_vec, bytes_written, error_details);
53   }
54   /* An error occurred. */
55   maybe_copy_error_msg(vtable_error_msg, error_details);
56   return GRPC_STATUS_INVALID_ARGUMENT;
57 }
58 
gsec_aead_crypter_encrypt_iovec(gsec_aead_crypter * crypter,const uint8_t * nonce,size_t nonce_length,const struct iovec * aad_vec,size_t aad_vec_length,const struct iovec * plaintext_vec,size_t plaintext_vec_length,struct iovec ciphertext_vec,size_t * ciphertext_bytes_written,char ** error_details)59 grpc_status_code gsec_aead_crypter_encrypt_iovec(
60     gsec_aead_crypter* crypter, const uint8_t* nonce, size_t nonce_length,
61     const struct iovec* aad_vec, size_t aad_vec_length,
62     const struct iovec* plaintext_vec, size_t plaintext_vec_length,
63     struct iovec ciphertext_vec, size_t* ciphertext_bytes_written,
64     char** error_details) {
65   if (crypter != nullptr && crypter->vtable != nullptr &&
66       crypter->vtable->encrypt_iovec != nullptr) {
67     return crypter->vtable->encrypt_iovec(
68         crypter, nonce, nonce_length, aad_vec, aad_vec_length, plaintext_vec,
69         plaintext_vec_length, ciphertext_vec, ciphertext_bytes_written,
70         error_details);
71   }
72   /* An error occurred. */
73   maybe_copy_error_msg(vtable_error_msg, error_details);
74   return GRPC_STATUS_INVALID_ARGUMENT;
75 }
76 
gsec_aead_crypter_decrypt(gsec_aead_crypter * crypter,const uint8_t * nonce,size_t nonce_length,const uint8_t * aad,size_t aad_length,const uint8_t * ciphertext_and_tag,size_t ciphertext_and_tag_length,uint8_t * plaintext,size_t plaintext_length,size_t * bytes_written,char ** error_details)77 grpc_status_code gsec_aead_crypter_decrypt(
78     gsec_aead_crypter* crypter, const uint8_t* nonce, size_t nonce_length,
79     const uint8_t* aad, size_t aad_length, const uint8_t* ciphertext_and_tag,
80     size_t ciphertext_and_tag_length, uint8_t* plaintext,
81     size_t plaintext_length, size_t* bytes_written, char** error_details) {
82   if (crypter != nullptr && crypter->vtable != nullptr &&
83       crypter->vtable->decrypt_iovec != nullptr) {
84     struct iovec aad_vec = {(void*)aad, aad_length};
85     struct iovec ciphertext_vec = {(void*)ciphertext_and_tag,
86                                    ciphertext_and_tag_length};
87     struct iovec plaintext_vec = {plaintext, plaintext_length};
88     return crypter->vtable->decrypt_iovec(
89         crypter, nonce, nonce_length, &aad_vec, 1, &ciphertext_vec, 1,
90         plaintext_vec, bytes_written, error_details);
91   }
92   /* An error occurred. */
93   maybe_copy_error_msg(vtable_error_msg, error_details);
94   return GRPC_STATUS_INVALID_ARGUMENT;
95 }
96 
gsec_aead_crypter_decrypt_iovec(gsec_aead_crypter * crypter,const uint8_t * nonce,size_t nonce_length,const struct iovec * aad_vec,size_t aad_vec_length,const struct iovec * ciphertext_vec,size_t ciphertext_vec_length,struct iovec plaintext_vec,size_t * plaintext_bytes_written,char ** error_details)97 grpc_status_code gsec_aead_crypter_decrypt_iovec(
98     gsec_aead_crypter* crypter, const uint8_t* nonce, size_t nonce_length,
99     const struct iovec* aad_vec, size_t aad_vec_length,
100     const struct iovec* ciphertext_vec, size_t ciphertext_vec_length,
101     struct iovec plaintext_vec, size_t* plaintext_bytes_written,
102     char** error_details) {
103   if (crypter != nullptr && crypter->vtable != nullptr &&
104       crypter->vtable->encrypt_iovec != nullptr) {
105     return crypter->vtable->decrypt_iovec(
106         crypter, nonce, nonce_length, aad_vec, aad_vec_length, ciphertext_vec,
107         ciphertext_vec_length, plaintext_vec, plaintext_bytes_written,
108         error_details);
109   }
110   /* An error occurred. */
111   maybe_copy_error_msg(vtable_error_msg, error_details);
112   return GRPC_STATUS_INVALID_ARGUMENT;
113 }
114 
gsec_aead_crypter_max_ciphertext_and_tag_length(const gsec_aead_crypter * crypter,size_t plaintext_length,size_t * max_ciphertext_and_tag_length_to_return,char ** error_details)115 grpc_status_code gsec_aead_crypter_max_ciphertext_and_tag_length(
116     const gsec_aead_crypter* crypter, size_t plaintext_length,
117     size_t* max_ciphertext_and_tag_length_to_return, char** error_details) {
118   if (crypter != nullptr && crypter->vtable != nullptr &&
119       crypter->vtable->max_ciphertext_and_tag_length != nullptr) {
120     return crypter->vtable->max_ciphertext_and_tag_length(
121         crypter, plaintext_length, max_ciphertext_and_tag_length_to_return,
122         error_details);
123   }
124   /* An error occurred. */
125   maybe_copy_error_msg(vtable_error_msg, error_details);
126   return GRPC_STATUS_INVALID_ARGUMENT;
127 }
128 
gsec_aead_crypter_max_plaintext_length(const gsec_aead_crypter * crypter,size_t ciphertext_and_tag_length,size_t * max_plaintext_length_to_return,char ** error_details)129 grpc_status_code gsec_aead_crypter_max_plaintext_length(
130     const gsec_aead_crypter* crypter, size_t ciphertext_and_tag_length,
131     size_t* max_plaintext_length_to_return, char** error_details) {
132   if (crypter != nullptr && crypter->vtable != nullptr &&
133       crypter->vtable->max_plaintext_length != nullptr) {
134     return crypter->vtable->max_plaintext_length(
135         crypter, ciphertext_and_tag_length, max_plaintext_length_to_return,
136         error_details);
137   }
138   /* An error occurred. */
139   maybe_copy_error_msg(vtable_error_msg, error_details);
140   return GRPC_STATUS_INVALID_ARGUMENT;
141 }
142 
gsec_aead_crypter_nonce_length(const gsec_aead_crypter * crypter,size_t * nonce_length_to_return,char ** error_details)143 grpc_status_code gsec_aead_crypter_nonce_length(
144     const gsec_aead_crypter* crypter, size_t* nonce_length_to_return,
145     char** error_details) {
146   if (crypter != nullptr && crypter->vtable != nullptr &&
147       crypter->vtable->nonce_length != nullptr) {
148     return crypter->vtable->nonce_length(crypter, nonce_length_to_return,
149                                          error_details);
150   }
151   /* An error occurred. */
152   maybe_copy_error_msg(vtable_error_msg, error_details);
153   return GRPC_STATUS_INVALID_ARGUMENT;
154 }
155 
gsec_aead_crypter_key_length(const gsec_aead_crypter * crypter,size_t * key_length_to_return,char ** error_details)156 grpc_status_code gsec_aead_crypter_key_length(const gsec_aead_crypter* crypter,
157                                               size_t* key_length_to_return,
158                                               char** error_details) {
159   if (crypter != nullptr && crypter->vtable != nullptr &&
160       crypter->vtable->key_length != nullptr) {
161     return crypter->vtable->key_length(crypter, key_length_to_return,
162                                        error_details);
163   }
164   /* An error occurred */
165   maybe_copy_error_msg(vtable_error_msg, error_details);
166   return GRPC_STATUS_INVALID_ARGUMENT;
167 }
168 
gsec_aead_crypter_tag_length(const gsec_aead_crypter * crypter,size_t * tag_length_to_return,char ** error_details)169 grpc_status_code gsec_aead_crypter_tag_length(const gsec_aead_crypter* crypter,
170                                               size_t* tag_length_to_return,
171                                               char** error_details) {
172   if (crypter != nullptr && crypter->vtable != nullptr &&
173       crypter->vtable->tag_length != nullptr) {
174     return crypter->vtable->tag_length(crypter, tag_length_to_return,
175                                        error_details);
176   }
177   /* An error occurred. */
178   maybe_copy_error_msg(vtable_error_msg, error_details);
179   return GRPC_STATUS_INVALID_ARGUMENT;
180 }
181 
gsec_aead_crypter_destroy(gsec_aead_crypter * crypter)182 void gsec_aead_crypter_destroy(gsec_aead_crypter* crypter) {
183   if (crypter != nullptr) {
184     if (crypter->vtable != nullptr && crypter->vtable->destruct != nullptr) {
185       crypter->vtable->destruct(crypter);
186     }
187     gpr_free(crypter);
188   }
189 }
190