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1 | /** @file\r |
2 | \r | |
3 | This library registers RSA 2048 SHA 256 guided section handler \r | |
4 | to parse RSA 2048 SHA 256 encapsulation section and extract raw data.\r | |
5 | It uses the BaseCrypyLib based on OpenSSL to authenticate the signature.\r | |
6 | \r | |
7 | Copyright (c) 2013 - 2014, Intel Corporation. All rights reserved.<BR>\r | |
8 | This program and the accompanying materials \r | |
9 | are licensed and made available under the terms and conditions of the BSD License \r | |
10 | which accompanies this distribution. The full text of the license may be found at \r | |
11 | http://opensource.org/licenses/bsd-license.php \r | |
12 | \r | |
13 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, \r | |
14 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. \r | |
15 | \r | |
16 | **/\r | |
17 | \r | |
18 | #include <PiDxe.h>\r | |
19 | #include <Protocol/Hash.h>\r | |
20 | #include <Protocol/SecurityPolicy.h>\r | |
21 | #include <Library/ExtractGuidedSectionLib.h>\r | |
22 | #include <Library/DebugLib.h>\r | |
23 | #include <Library/BaseMemoryLib.h>\r | |
24 | #include <Library/MemoryAllocationLib.h>\r | |
25 | #include <Library/UefiBootServicesTableLib.h>\r | |
26 | #include <Library/PcdLib.h>\r | |
27 | #include <Guid/WinCertificate.h>\r | |
28 | #include <Library/BaseCryptLib.h>\r | |
29 | #include <Library/PerformanceLib.h>\r | |
30 | #include <Guid/SecurityPkgTokenSpace.h>\r | |
31 | \r | |
32 | ///\r | |
33 | /// RSA 2048 SHA 256 Guided Section header\r | |
34 | ///\r | |
35 | typedef struct {\r | |
36 | EFI_GUID_DEFINED_SECTION GuidedSectionHeader; ///< EFI guided section header\r | |
37 | EFI_CERT_BLOCK_RSA_2048_SHA256 CertBlockRsa2048Sha256; ///< RSA 2048-bit Signature\r | |
38 | } RSA_2048_SHA_256_SECTION_HEADER;\r | |
39 | \r | |
40 | typedef struct {\r | |
41 | EFI_GUID_DEFINED_SECTION2 GuidedSectionHeader; ///< EFI guided section header\r | |
42 | EFI_CERT_BLOCK_RSA_2048_SHA256 CertBlockRsa2048Sha256; ///< RSA 2048-bit Signature\r | |
43 | } RSA_2048_SHA_256_SECTION2_HEADER;\r | |
44 | \r | |
45 | ///\r | |
46 | /// Public Exponent of RSA Key.\r | |
47 | ///\r | |
48 | CONST UINT8 mRsaE[] = { 0x01, 0x00, 0x01 };\r | |
49 | \r | |
50 | /**\r | |
51 | \r | |
52 | GetInfo gets raw data size and attribute of the input guided section.\r | |
53 | It first checks whether the input guid section is supported. \r | |
54 | If not, EFI_INVALID_PARAMETER will return.\r | |
55 | \r | |
56 | @param InputSection Buffer containing the input GUIDed section to be processed.\r | |
57 | @param OutputBufferSize The size of OutputBuffer.\r | |
58 | @param ScratchBufferSize The size of ScratchBuffer.\r | |
59 | @param SectionAttribute The attribute of the input guided section.\r | |
60 | \r | |
61 | @retval EFI_SUCCESS The size of destination buffer, the size of scratch buffer and \r | |
62 | the attribute of the input section are successull retrieved.\r | |
63 | @retval EFI_INVALID_PARAMETER The GUID in InputSection does not match this instance guid.\r | |
64 | \r | |
65 | **/\r | |
66 | EFI_STATUS\r | |
67 | EFIAPI\r | |
68 | Rsa2048Sha256GuidedSectionGetInfo (\r | |
69 | IN CONST VOID *InputSection,\r | |
70 | OUT UINT32 *OutputBufferSize,\r | |
71 | OUT UINT32 *ScratchBufferSize,\r | |
72 | OUT UINT16 *SectionAttribute\r | |
73 | )\r | |
74 | {\r | |
75 | if (IS_SECTION2 (InputSection)) {\r | |
76 | //\r | |
77 | // Check whether the input guid section is recognized.\r | |
78 | //\r | |
79 | if (!CompareGuid (\r | |
80 | &gEfiCertTypeRsa2048Sha256Guid,\r | |
81 | &(((EFI_GUID_DEFINED_SECTION2 *) InputSection)->SectionDefinitionGuid))) {\r | |
82 | return EFI_INVALID_PARAMETER;\r | |
83 | }\r | |
84 | //\r | |
85 | // Retrieve the size and attribute of the input section data.\r | |
86 | //\r | |
87 | *SectionAttribute = ((EFI_GUID_DEFINED_SECTION2 *) InputSection)->Attributes;\r | |
88 | *ScratchBufferSize = 0;\r | |
89 | *OutputBufferSize = SECTION2_SIZE (InputSection) - ((EFI_GUID_DEFINED_SECTION2 *) InputSection)->DataOffset;\r | |
90 | } else {\r | |
91 | //\r | |
92 | // Check whether the input guid section is recognized.\r | |
93 | //\r | |
94 | if (!CompareGuid (\r | |
95 | &gEfiCertTypeRsa2048Sha256Guid,\r | |
96 | &(((EFI_GUID_DEFINED_SECTION *) InputSection)->SectionDefinitionGuid))) {\r | |
97 | return EFI_INVALID_PARAMETER;\r | |
98 | }\r | |
99 | //\r | |
100 | // Retrieve the size and attribute of the input section data.\r | |
101 | //\r | |
102 | *SectionAttribute = ((EFI_GUID_DEFINED_SECTION *) InputSection)->Attributes;\r | |
103 | *ScratchBufferSize = 0;\r | |
104 | *OutputBufferSize = SECTION_SIZE (InputSection) - ((EFI_GUID_DEFINED_SECTION *) InputSection)->DataOffset;\r | |
105 | }\r | |
106 | \r | |
107 | return EFI_SUCCESS;\r | |
108 | }\r | |
109 | \r | |
110 | /**\r | |
111 | \r | |
112 | Extraction handler tries to extract raw data from the input guided section.\r | |
113 | It also does authentication check for RSA 2048 SHA 256 signature in the input guided section.\r | |
114 | It first checks whether the input guid section is supported. \r | |
115 | If not, EFI_INVALID_PARAMETER will return.\r | |
116 | \r | |
117 | @param InputSection Buffer containing the input GUIDed section to be processed.\r | |
118 | @param OutputBuffer Buffer to contain the output raw data allocated by the caller.\r | |
119 | @param ScratchBuffer A pointer to a caller-allocated buffer for function internal use.\r | |
120 | @param AuthenticationStatus A pointer to a caller-allocated UINT32 that indicates the\r | |
121 | authentication status of the output buffer.\r | |
122 | \r | |
123 | @retval EFI_SUCCESS Section Data and Auth Status is extracted successfully.\r | |
124 | @retval EFI_INVALID_PARAMETER The GUID in InputSection does not match this instance guid.\r | |
125 | \r | |
126 | **/\r | |
127 | EFI_STATUS\r | |
128 | EFIAPI\r | |
129 | Rsa2048Sha256GuidedSectionHandler (\r | |
130 | IN CONST VOID *InputSection,\r | |
131 | OUT VOID **OutputBuffer,\r | |
132 | IN VOID *ScratchBuffer, OPTIONAL\r | |
133 | OUT UINT32 *AuthenticationStatus\r | |
134 | )\r | |
135 | {\r | |
136 | EFI_STATUS Status;\r | |
137 | UINT32 OutputBufferSize;\r | |
138 | VOID *DummyInterface;\r | |
139 | EFI_CERT_BLOCK_RSA_2048_SHA256 *CertBlockRsa2048Sha256;\r | |
140 | BOOLEAN CryptoStatus;\r | |
141 | UINT8 Digest[SHA256_DIGEST_SIZE];\r | |
142 | UINT8 *PublicKey;\r | |
143 | UINTN PublicKeyBufferSize;\r | |
144 | VOID *HashContext;\r | |
145 | VOID *Rsa;\r | |
146 | \r | |
147 | HashContext = NULL;\r | |
148 | Rsa = NULL;\r | |
149 | \r | |
150 | if (IS_SECTION2 (InputSection)) {\r | |
151 | //\r | |
152 | // Check whether the input guid section is recognized.\r | |
153 | //\r | |
154 | if (!CompareGuid (\r | |
155 | &gEfiCertTypeRsa2048Sha256Guid,\r | |
156 | &(((EFI_GUID_DEFINED_SECTION2 *)InputSection)->SectionDefinitionGuid))) {\r | |
157 | return EFI_INVALID_PARAMETER;\r | |
158 | }\r | |
159 | \r | |
160 | //\r | |
161 | // Get the RSA 2048 SHA 256 information.\r | |
162 | //\r | |
163 | CertBlockRsa2048Sha256 = &((RSA_2048_SHA_256_SECTION2_HEADER *) InputSection)->CertBlockRsa2048Sha256;\r | |
164 | OutputBufferSize = SECTION2_SIZE (InputSection) - sizeof (RSA_2048_SHA_256_SECTION2_HEADER);\r | |
165 | if ((((EFI_GUID_DEFINED_SECTION *)InputSection)->Attributes & EFI_GUIDED_SECTION_PROCESSING_REQUIRED) != 0) {\r | |
166 | PERF_START (NULL, "RsaCopy", "DXE", 0);\r | |
167 | CopyMem (*OutputBuffer, (UINT8 *)InputSection + sizeof (RSA_2048_SHA_256_SECTION2_HEADER), OutputBufferSize);\r | |
168 | PERF_END (NULL, "RsaCopy", "DXE", 0);\r | |
169 | } else {\r | |
170 | *OutputBuffer = (UINT8 *)InputSection + sizeof (RSA_2048_SHA_256_SECTION2_HEADER);\r | |
171 | }\r | |
172 | \r | |
173 | //\r | |
174 | // Implicitly RSA 2048 SHA 256 GUIDed section should have STATUS_VALID bit set\r | |
175 | //\r | |
176 | ASSERT ((((EFI_GUID_DEFINED_SECTION2 *)InputSection)->Attributes & EFI_GUIDED_SECTION_AUTH_STATUS_VALID) != 0);\r | |
177 | *AuthenticationStatus = EFI_AUTH_STATUS_IMAGE_SIGNED;\r | |
178 | } else {\r | |
179 | //\r | |
180 | // Check whether the input guid section is recognized.\r | |
181 | //\r | |
182 | if (!CompareGuid (\r | |
183 | &gEfiCertTypeRsa2048Sha256Guid,\r | |
184 | &(((EFI_GUID_DEFINED_SECTION *)InputSection)->SectionDefinitionGuid))) {\r | |
185 | return EFI_INVALID_PARAMETER;\r | |
186 | }\r | |
187 | \r | |
188 | //\r | |
189 | // Get the RSA 2048 SHA 256 information.\r | |
190 | //\r | |
191 | CertBlockRsa2048Sha256 = &((RSA_2048_SHA_256_SECTION_HEADER *)InputSection)->CertBlockRsa2048Sha256;\r | |
192 | OutputBufferSize = SECTION_SIZE (InputSection) - sizeof (RSA_2048_SHA_256_SECTION_HEADER);\r | |
193 | if ((((EFI_GUID_DEFINED_SECTION *)InputSection)->Attributes & EFI_GUIDED_SECTION_PROCESSING_REQUIRED) != 0) {\r | |
194 | PERF_START (NULL, "RsaCopy", "DXE", 0);\r | |
195 | CopyMem (*OutputBuffer, (UINT8 *)InputSection + sizeof (RSA_2048_SHA_256_SECTION_HEADER), OutputBufferSize);\r | |
196 | PERF_END (NULL, "RsaCopy", "DXE", 0);\r | |
197 | } else {\r | |
198 | *OutputBuffer = (UINT8 *)InputSection + sizeof (RSA_2048_SHA_256_SECTION_HEADER);\r | |
199 | }\r | |
200 | \r | |
201 | //\r | |
202 | // Implicitly RSA 2048 SHA 256 GUIDed section should have STATUS_VALID bit set\r | |
203 | //\r | |
204 | ASSERT ((((EFI_GUID_DEFINED_SECTION *) InputSection)->Attributes & EFI_GUIDED_SECTION_AUTH_STATUS_VALID) != 0);\r | |
205 | *AuthenticationStatus = EFI_AUTH_STATUS_IMAGE_SIGNED;\r | |
206 | }\r | |
207 | \r | |
208 | //\r | |
209 | // Check whether there exists EFI_SECURITY_POLICY_PROTOCOL_GUID.\r | |
210 | //\r | |
211 | Status = gBS->LocateProtocol (&gEfiSecurityPolicyProtocolGuid, NULL, &DummyInterface);\r | |
212 | if (!EFI_ERROR (Status)) {\r | |
213 | //\r | |
214 | // If SecurityPolicy Protocol exist, AUTH platform override bit is set.\r | |
215 | //\r | |
216 | *AuthenticationStatus |= EFI_AUTH_STATUS_PLATFORM_OVERRIDE;\r | |
217 | \r | |
218 | return EFI_SUCCESS;\r | |
219 | }\r | |
220 | \r | |
221 | //\r | |
222 | // All paths from here return EFI_SUCESS and result is returned in AuthenticationStatus\r | |
223 | //\r | |
224 | Status = EFI_SUCCESS;\r | |
225 | \r | |
226 | //\r | |
227 | // Fail if the HashType is not SHA 256\r | |
228 | //\r | |
229 | if (!CompareGuid (&gEfiHashAlgorithmSha256Guid, &CertBlockRsa2048Sha256->HashType)) {\r | |
230 | DEBUG ((DEBUG_ERROR, "DxeRsa2048Sha256: HASH type of section is not supported\n"));\r | |
231 | *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED;\r | |
232 | goto Done;\r | |
233 | }\r | |
234 | \r | |
235 | //\r | |
236 | // Allocate hash context buffer required for SHA 256\r | |
237 | //\r | |
238 | HashContext = AllocatePool (Sha256GetContextSize ());\r | |
239 | if (HashContext == NULL) {\r | |
240 | DEBUG ((DEBUG_ERROR, "DxeRsa2048Sha256: Can not allocate hash context\n"));\r | |
241 | *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED;\r | |
242 | goto Done;\r | |
243 | }\r | |
244 | \r | |
245 | //\r | |
246 | // Hash public key from data payload with SHA256.\r | |
247 | //\r | |
248 | ZeroMem (Digest, SHA256_DIGEST_SIZE);\r | |
249 | CryptoStatus = Sha256Init (HashContext);\r | |
250 | if (!CryptoStatus) {\r | |
251 | DEBUG ((DEBUG_ERROR, "DxeRsa2048Sha256: Sha256Init() failed\n"));\r | |
252 | *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED;\r | |
253 | goto Done;\r | |
254 | }\r | |
255 | CryptoStatus = Sha256Update (HashContext, &CertBlockRsa2048Sha256->PublicKey, sizeof(CertBlockRsa2048Sha256->PublicKey));\r | |
256 | if (!CryptoStatus) {\r | |
257 | DEBUG ((DEBUG_ERROR, "DxeRsa2048Sha256: Sha256Update() failed\n"));\r | |
258 | *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED;\r | |
259 | goto Done;\r | |
260 | }\r | |
261 | CryptoStatus = Sha256Final (HashContext, Digest);\r | |
262 | if (!CryptoStatus) {\r | |
263 | DEBUG ((DEBUG_ERROR, "DxeRsa2048Sha256: Sha256Final() failed\n"));\r | |
264 | *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED;\r | |
265 | goto Done;\r | |
266 | }\r | |
267 | \r | |
268 | //\r | |
269 | // Fail if the PublicKey is not one of the public keys in PcdRsa2048Sha256PublicKeyBuffer\r | |
270 | //\r | |
271 | PublicKey = (UINT8 *)PcdGetPtr (PcdRsa2048Sha256PublicKeyBuffer);\r | |
272 | DEBUG ((DEBUG_VERBOSE, "DxePcdRsa2048Sha256: PublicKeyBuffer = %p\n", PublicKey));\r | |
273 | ASSERT (PublicKey != NULL);\r | |
274 | DEBUG ((DEBUG_VERBOSE, "DxePcdRsa2048Sha256: PublicKeyBuffer Token = %08x\n", PcdToken (PcdRsa2048Sha256PublicKeyBuffer)));\r | |
275 | PublicKeyBufferSize = LibPcdGetExSize (&gEfiSecurityPkgTokenSpaceGuid, PcdToken (PcdRsa2048Sha256PublicKeyBuffer));\r | |
276 | DEBUG ((DEBUG_VERBOSE, "DxePcdRsa2048Sha256: PublicKeyBuffer Size = %08x\n", PublicKeyBufferSize));\r | |
277 | ASSERT ((PublicKeyBufferSize % SHA256_DIGEST_SIZE) == 0);\r | |
278 | CryptoStatus = FALSE;\r | |
279 | while (PublicKeyBufferSize != 0) {\r | |
280 | if (CompareMem (Digest, PublicKey, SHA256_DIGEST_SIZE) == 0) {\r | |
281 | CryptoStatus = TRUE;\r | |
282 | break;\r | |
283 | }\r | |
284 | PublicKey = PublicKey + SHA256_DIGEST_SIZE;\r | |
285 | PublicKeyBufferSize = PublicKeyBufferSize - SHA256_DIGEST_SIZE;\r | |
286 | }\r | |
287 | if (!CryptoStatus) {\r | |
288 | DEBUG ((DEBUG_ERROR, "DxeRsa2048Sha256: Public key in section is not supported\n"));\r | |
289 | *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED;\r | |
290 | goto Done;\r | |
291 | }\r | |
292 | \r | |
293 | //\r | |
294 | // Generate & Initialize RSA Context.\r | |
295 | //\r | |
296 | Rsa = RsaNew ();\r | |
297 | if (Rsa == NULL) {\r | |
298 | DEBUG ((DEBUG_ERROR, "DxeRsa2048Sha256: RsaNew() failed\n"));\r | |
299 | *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED;\r | |
300 | goto Done;\r | |
301 | }\r | |
302 | \r | |
303 | // \r | |
304 | // Set RSA Key Components.\r | |
305 | // NOTE: Only N and E are needed to be set as RSA public key for signature verification.\r | |
306 | //\r | |
307 | CryptoStatus = RsaSetKey (Rsa, RsaKeyN, CertBlockRsa2048Sha256->PublicKey, sizeof(CertBlockRsa2048Sha256->PublicKey));\r | |
308 | if (!CryptoStatus) {\r | |
309 | DEBUG ((DEBUG_ERROR, "DxeRsa2048Sha256: RsaSetKey(RsaKeyN) failed\n"));\r | |
310 | *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED;\r | |
311 | goto Done;\r | |
312 | }\r | |
313 | CryptoStatus = RsaSetKey (Rsa, RsaKeyE, mRsaE, sizeof (mRsaE));\r | |
314 | if (!CryptoStatus) {\r | |
315 | DEBUG ((DEBUG_ERROR, "DxeRsa2048Sha256: RsaSetKey(RsaKeyE) failed\n"));\r | |
316 | *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED;\r | |
317 | goto Done;\r | |
318 | }\r | |
319 | \r | |
320 | //\r | |
321 | // Hash data payload with SHA256.\r | |
322 | //\r | |
323 | ZeroMem (Digest, SHA256_DIGEST_SIZE);\r | |
324 | CryptoStatus = Sha256Init (HashContext);\r | |
325 | if (!CryptoStatus) {\r | |
326 | DEBUG ((DEBUG_ERROR, "DxeRsa2048Sha256: Sha256Init() failed\n"));\r | |
327 | *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED;\r | |
328 | goto Done;\r | |
329 | }\r | |
330 | PERF_START (NULL, "RsaShaData", "DXE", 0);\r | |
331 | CryptoStatus = Sha256Update (HashContext, *OutputBuffer, OutputBufferSize);\r | |
332 | PERF_END (NULL, "RsaShaData", "DXE", 0);\r | |
333 | if (!CryptoStatus) {\r | |
334 | DEBUG ((DEBUG_ERROR, "DxeRsa2048Sha256: Sha256Update() failed\n"));\r | |
335 | *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED;\r | |
336 | goto Done;\r | |
337 | }\r | |
338 | CryptoStatus = Sha256Final (HashContext, Digest);\r | |
339 | if (!CryptoStatus) {\r | |
340 | DEBUG ((DEBUG_ERROR, "DxeRsa2048Sha256: Sha256Final() failed\n"));\r | |
341 | *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED;\r | |
342 | goto Done;\r | |
343 | }\r | |
344 | \r | |
345 | //\r | |
346 | // Verify the RSA 2048 SHA 256 signature.\r | |
347 | //\r | |
348 | PERF_START (NULL, "RsaVerify", "DXE", 0);\r | |
349 | CryptoStatus = RsaPkcs1Verify (\r | |
350 | Rsa, \r | |
351 | Digest, \r | |
352 | SHA256_DIGEST_SIZE, \r | |
353 | CertBlockRsa2048Sha256->Signature, \r | |
354 | sizeof (CertBlockRsa2048Sha256->Signature)\r | |
355 | );\r | |
356 | PERF_END (NULL, "RsaVerify", "DXE", 0);\r | |
357 | if (!CryptoStatus) {\r | |
358 | //\r | |
359 | // If RSA 2048 SHA 256 signature verification fails, AUTH tested failed bit is set.\r | |
360 | //\r | |
361 | DEBUG ((DEBUG_ERROR, "DxeRsa2048Sha256: RsaPkcs1Verify() failed\n"));\r | |
362 | *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED;\r | |
363 | }\r | |
364 | \r | |
365 | Done:\r | |
366 | //\r | |
367 | // Free allocated resources used to perform RSA 2048 SHA 256 signature verification\r | |
368 | //\r | |
369 | if (Rsa != NULL) {\r | |
370 | RsaFree (Rsa);\r | |
371 | }\r | |
372 | if (HashContext != NULL) {\r | |
373 | FreePool (HashContext);\r | |
374 | }\r | |
375 | \r | |
376 | DEBUG ((DEBUG_VERBOSE, "DxeRsa2048Sha256: Status = %r AuthenticationStatus = %08x\n", Status, *AuthenticationStatus));\r | |
377 | \r | |
378 | return Status;\r | |
379 | }\r | |
380 | \r | |
381 | /**\r | |
382 | Register the handler to extract RSA 2048 SHA 256 guided section.\r | |
383 | \r | |
384 | @param ImageHandle ImageHandle of the loaded driver.\r | |
385 | @param SystemTable Pointer to the EFI System Table.\r | |
386 | \r | |
387 | @retval EFI_SUCCESS Register successfully.\r | |
388 | @retval EFI_OUT_OF_RESOURCES Not enough memory to register this handler.\r | |
389 | **/\r | |
390 | EFI_STATUS\r | |
391 | EFIAPI\r | |
392 | DxeRsa2048Sha256GuidedSectionExtractLibConstructor (\r | |
393 | IN EFI_HANDLE ImageHandle,\r | |
394 | IN EFI_SYSTEM_TABLE *SystemTable\r | |
395 | )\r | |
396 | {\r | |
397 | return ExtractGuidedSectionRegisterHandlers (\r | |
398 | &gEfiCertTypeRsa2048Sha256Guid,\r | |
399 | Rsa2048Sha256GuidedSectionGetInfo,\r | |
400 | Rsa2048Sha256GuidedSectionHandler\r | |
401 | );\r | |
402 | }\r |