Botan  2.9.0
Crypto and TLS for C++11
ffi.cpp
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1 /*
2 * (C) 2015,2017 Jack Lloyd
3 *
4 * Botan is released under the Simplified BSD License (see license.txt)
5 */
6 
7 #include <botan/ffi.h>
8 #include <botan/internal/ffi_util.h>
9 #include <botan/internal/os_utils.h>
10 #include <botan/version.h>
11 #include <botan/mem_ops.h>
12 #include <botan/hex.h>
13 #include <botan/base64.h>
14 #include <cstdio>
15 #include <cstdlib>
16 
17 namespace Botan_FFI {
18 
19 int ffi_error_exception_thrown(const char* func_name, const char* exn, int rc)
20  {
21  if(Botan::OS::read_env_variable("BOTAN_FFI_PRINT_EXCEPTIONS") != nullptr)
22  {
23  std::fprintf(stderr, "in %s exception '%s' returning %d\n", func_name, exn, rc);
24  }
25  return rc;
26  }
27 
28 namespace {
29 
30 int ffi_map_error_type(Botan::ErrorType err)
31  {
32  switch(err)
33  {
46 
60 
64 
69 
74  }
75 
77  }
78 
79 }
80 
81 int ffi_guard_thunk(const char* func_name, std::function<int ()> thunk)
82  {
83  try
84  {
85  return thunk();
86  }
87  catch(std::bad_alloc&)
88  {
89  return ffi_error_exception_thrown(func_name, "bad_alloc", BOTAN_FFI_ERROR_OUT_OF_MEMORY);
90  }
91  catch(Botan_FFI::FFI_Error& e)
92  {
93  return ffi_error_exception_thrown(func_name, e.what(), e.error_code());
94  }
95  catch(Botan::Exception& e)
96  {
97  return ffi_error_exception_thrown(func_name, e.what(), ffi_map_error_type(e.error_type()));
98  }
99  catch(std::exception& e)
100  {
101  return ffi_error_exception_thrown(func_name, e.what());
102  }
103  catch(...)
104  {
105  return ffi_error_exception_thrown(func_name, "unknown exception");
106  }
107 
109  }
110 
111 }
112 
113 extern "C" {
114 
115 using namespace Botan_FFI;
116 
117 const char* botan_error_description(int err)
118  {
119  switch(err)
120  {
121  case BOTAN_FFI_SUCCESS:
122  return "OK";
123 
125  return "Invalid verifier";
126 
128  return "Invalid input";
129 
131  return "Invalid authentication code";
132 
134  return "Insufficient buffer space";
135 
137  return "Exception thrown";
138 
140  return "Out of memory";
141 
143  return "Error while calling system API";
144 
146  return "Internal error";
147 
149  return "Bad flag";
150 
152  return "Null pointer argument";
153 
155  return "Bad parameter";
156 
158  return "Key not set on object";
159 
161  return "Invalid key length";
162 
164  return "Invalid object state";
165 
167  return "Not implemented";
168 
170  return "Invalid object handle";
171 
173  return "TLS error";
174 
176  return "HTTP error";
177 
179  return "Unknown error";
180  }
181 
182  return "Unknown error";
183  }
184 
185 /*
186 * Versioning
187 */
189  {
190  return BOTAN_HAS_FFI;
191  }
192 
193 int botan_ffi_supports_api(uint32_t api_version)
194  {
195  // This is the API introduced in 2.8
196  if(api_version == 20180713)
197  return BOTAN_FFI_SUCCESS;
198 
199  // This is the API introduced in 2.3
200  if(api_version == 20170815)
201  return BOTAN_FFI_SUCCESS;
202 
203  // This is the API introduced in 2.1
204  if(api_version == 20170327)
205  return BOTAN_FFI_SUCCESS;
206 
207  // This is the API introduced in 2.0
208  if(api_version == 20150515)
209  return BOTAN_FFI_SUCCESS;
210 
211  // Something else:
212  return -1;
213  }
214 
215 const char* botan_version_string()
216  {
217  return Botan::version_cstr();
218  }
219 
224 
225 int botan_constant_time_compare(const uint8_t* x, const uint8_t* y, size_t len)
226  {
227  return Botan::constant_time_compare(x, y, len) ? 0 : -1;
228  }
229 
230 int botan_same_mem(const uint8_t* x, const uint8_t* y, size_t len)
231  {
232  return botan_constant_time_compare(x, y, len);
233  }
234 
235 int botan_scrub_mem(void* mem, size_t bytes)
236  {
237  Botan::secure_scrub_memory(mem, bytes);
238  return BOTAN_FFI_SUCCESS;
239  }
240 
241 int botan_hex_encode(const uint8_t* in, size_t len, char* out, uint32_t flags)
242  {
243  return ffi_guard_thunk(__func__, [=]() -> int {
244  const bool uppercase = (flags & BOTAN_FFI_HEX_LOWER_CASE) == 0;
245  Botan::hex_encode(out, in, len, uppercase);
246  return BOTAN_FFI_SUCCESS;
247  });
248  }
249 
250 int botan_hex_decode(const char* hex_str, size_t in_len, uint8_t* out, size_t* out_len)
251  {
252  return ffi_guard_thunk(__func__, [=]() -> int {
253  const std::vector<uint8_t> bin = Botan::hex_decode(hex_str, in_len);
254  return Botan_FFI::write_vec_output(out, out_len, bin);
255  });
256  }
257 
258 int botan_base64_encode(const uint8_t* in, size_t len, char* out, size_t* out_len)
259  {
260  return ffi_guard_thunk(__func__, [=]() -> int {
261  const std::string base64 = Botan::base64_encode(in, len);
262  return Botan_FFI::write_str_output(out, out_len, base64);
263  });
264  }
265 
266 int botan_base64_decode(const char* base64_str, size_t in_len,
267  uint8_t* out, size_t* out_len)
268  {
269  return ffi_guard_thunk(__func__, [=]() -> int {
270  if(*out_len < Botan::base64_decode_max_output(in_len))
271  {
272  *out_len = Botan::base64_decode_max_output(in_len);
274  }
275 
276  *out_len = Botan::base64_decode(out, std::string(base64_str, in_len));
277  return BOTAN_FFI_SUCCESS;
278  });
279  }
280 
281 }
int ffi_guard_thunk(const char *func_name, std::function< int()> thunk)
Definition: ffi.cpp:81
void hex_encode(char output[], const uint8_t input[], size_t input_length, bool uppercase)
Definition: hex.cpp:14
int botan_hex_encode(const uint8_t *in, size_t len, char *out, uint32_t flags)
Definition: ffi.cpp:241
int ffi_error_exception_thrown(const char *func_name, const char *exn, int rc)
Definition: ffi.cpp:19
size_t base64_decode_max_output(size_t input_length)
Definition: base64.cpp:224
virtual ErrorType error_type() const noexcept
Definition: exceptn.h:92
Flags flags(Flag flags)
Definition: p11.h:858
bool constant_time_compare(const uint8_t x[], const uint8_t y[], size_t len)
Definition: mem_ops.h:81
int write_vec_output(uint8_t out[], size_t *out_len, const std::vector< uint8_t, Alloc > &buf)
Definition: ffi_util.h:142
#define BOTAN_FFI_HEX_LOWER_CASE
Definition: ffi.h:152
int error_code() const noexcept override
Definition: ffi_util.h:27
const char * what() const noexcept override
Definition: exceptn.h:87
int botan_base64_encode(const uint8_t *in, size_t len, char *out, size_t *out_len)
Definition: ffi.cpp:258
uint32_t botan_version_patch()
Definition: ffi.cpp:222
int botan_scrub_mem(void *mem, size_t bytes)
Definition: ffi.cpp:235
uint32_t version_major()
Definition: version.cpp:72
int write_str_output(uint8_t out[], size_t *out_len, const std::string &str)
Definition: ffi_util.h:147
size_t base64_encode(char out[], const uint8_t in[], size_t input_length, size_t &input_consumed, bool final_inputs)
Definition: base64.cpp:166
uint32_t botan_ffi_api_version()
Definition: ffi.cpp:188
uint32_t version_patch()
Definition: version.cpp:74
ErrorType
Definition: exceptn.h:20
uint32_t botan_version_major()
Definition: ffi.cpp:220
int botan_same_mem(const uint8_t *x, const uint8_t *y, size_t len)
Definition: ffi.cpp:230
uint32_t version_minor()
Definition: version.cpp:73
size_t hex_decode(uint8_t output[], const char input[], size_t input_length, size_t &input_consumed, bool ignore_ws)
Definition: hex.cpp:49
const char * botan_error_description(int err)
Definition: ffi.cpp:117
uint32_t botan_version_minor()
Definition: ffi.cpp:221
uint32_t version_datestamp()
Definition: version.cpp:67
int botan_base64_decode(const char *base64_str, size_t in_len, uint8_t *out, size_t *out_len)
Definition: ffi.cpp:266
void secure_scrub_memory(void *ptr, size_t n)
Definition: os_utils.cpp:50
size_t base64_decode(uint8_t out[], const char in[], size_t input_length, size_t &input_consumed, bool final_inputs, bool ignore_ws)
Definition: base64.cpp:181
uint32_t botan_version_datestamp()
Definition: ffi.cpp:223
int botan_hex_decode(const char *hex_str, size_t in_len, uint8_t *out, size_t *out_len)
Definition: ffi.cpp:250
int botan_ffi_supports_api(uint32_t api_version)
Definition: ffi.cpp:193
int botan_constant_time_compare(const uint8_t *x, const uint8_t *y, size_t len)
Definition: ffi.cpp:225
const char * version_cstr()
Definition: version.cpp:29
const char * read_env_variable(const std::string &var_name)
Definition: os_utils.cpp:328
const char * botan_version_string()
Definition: ffi.cpp:215