Azure IoT common library
Dependents: STM32F746_iothub_client_sample_mqtt f767zi_mqtt iothub_client_sample_amqp iothub_client_sample_http ... more
sha1.c
- Committer:
- Azure.IoT Build
- Date:
- 2016-04-08
- Revision:
- 0:fa2de1b79154
- Child:
- 15:956c6d205aa7
File content as of revision 0:fa2de1b79154:
// Copyright (c) Microsoft. All rights reserved. // Licensed under the MIT license. See LICENSE file in the project root for full license information. /**************************** sha1.c ****************************/ /******************** See RFC 4634 for details ******************/ /* * Description: * This file implements the Secure Hash Signature Standard * algorithms as defined in the National Institute of Standards * and Technology Federal Information Processing Standards * Publication (FIPS PUB) 180-1 published on April 17, 1995, 180-2 * published on August 1, 2002, and the FIPS PUB 180-2 Change * Notice published on February 28, 2004. * * A combined document showing all algorithms is available at * http://csrc.nist.gov/publications/fips/ * fips180-2/fips180-2withchangenotice.pdf * * The SHA-1 algorithm produces a 160-bit message digest for a * given data stream. It should take about 2**n steps to find a * message with the same digest as a given message and * 2**(n/2) to find any two messages with the same digest, * when n is the digest size in bits. Therefore, this * algorithm can serve as a means of providing a * "fingerprint" for a message. * * Portability Issues: * SHA-1 is defined in terms of 32-bit "words". This code * uses <stdint.h> (included via "sha.h") to define 32 and 8 * bit unsigned integer types. If your C compiler does not * support 32 bit unsigned integers, this code is not * appropriate. * * Caveats: * SHA-1 is designed to work with messages less than 2^64 bits * long. This implementation uses SHA1Input() to hash the bits * that are a multiple of the size of an 8-bit character, and then * uses SHA1FinalBits() to hash the final few bits of the input. */ #include <stdlib.h> #ifdef _CRTDBG_MAP_ALLOC #include <crtdbg.h> #endif #include "azure_c_shared_utility/gballoc.h" #include "azure_c_shared_utility/sha.h" #include "azure_c_shared_utility/sha-private.h" /* * Define the SHA1 circular left shift macro */ #define SHA1_ROTL(bits,word) \ (((word) << (bits)) | ((word) >> (32-(bits)))) /* * add "length" to the length */ static uint32_t addTemp; #define SHA1AddLength(context, length) \ (addTemp = (context)->Length_Low, \ (context)->Corrupted = \ (((context)->Length_Low += (length)) < addTemp) && \ (++(context)->Length_High == 0) ? 1 : 0) /* Local Function Prototypes */ static void SHA1Finalize(SHA1Context *context, uint8_t Pad_Byte); static void SHA1PadMessage(SHA1Context *, uint8_t Pad_Byte); static void SHA1ProcessMessageBlock(SHA1Context *); /* * SHA1Reset * * Description: * This function will initialize the SHA1Context in preparation * for computing a new SHA1 message digest. * * Parameters: * context: [in/out] * The context to reset. * * Returns: * sha Error Code. * */ int SHA1Reset(SHA1Context *context) { if (!context) return shaNull; context->Length_Low = 0; context->Length_High = 0; context->Message_Block_Index = 0; /* Initial Hash Values: FIPS-180-2 section 5.3.1 */ context->Intermediate_Hash[0] = 0x67452301; context->Intermediate_Hash[1] = 0xEFCDAB89; context->Intermediate_Hash[2] = 0x98BADCFE; context->Intermediate_Hash[3] = 0x10325476; context->Intermediate_Hash[4] = 0xC3D2E1F0; context->Computed = 0; context->Corrupted = 0; return shaSuccess; } /* * SHA1Input * * Description: * This function accepts an array of octets as the next portion * of the message. * * Parameters: * context: [in/out] * The SHA context to update * message_array: [in] * An array of characters representing the next portion of * the message. * length: [in] * The length of the message in message_array * * Returns: * sha Error Code. * */ int SHA1Input(SHA1Context *context, const uint8_t *message_array, unsigned length) { if (!length) return shaSuccess; if (!context || !message_array) return shaNull; if (context->Computed) { context->Corrupted = shaStateError; return shaStateError; } if (context->Corrupted) return context->Corrupted; while (length-- && !context->Corrupted) { context->Message_Block[context->Message_Block_Index++] = (*message_array & 0xFF); if (!SHA1AddLength(context, 8) && (context->Message_Block_Index == SHA1_Message_Block_Size)) SHA1ProcessMessageBlock(context); message_array++; } return shaSuccess; } /* * SHA1FinalBits * * Description: * This function will add in any final bits of the message. * * Parameters: * context: [in/out] * The SHA context to update * message_bits: [in] * The final bits of the message, in the upper portion of the * byte. (Use 0b###00000 instead of 0b00000### to input the * three bits ###.) * length: [in] * The number of bits in message_bits, between 1 and 7. * * Returns: * sha Error Code. */ int SHA1FinalBits(SHA1Context *context, const uint8_t message_bits, unsigned int length) { uint8_t masks[8] = { /* 0 0b00000000 */ 0x00, /* 1 0b10000000 */ 0x80, /* 2 0b11000000 */ 0xC0, /* 3 0b11100000 */ 0xE0, /* 4 0b11110000 */ 0xF0, /* 5 0b11111000 */ 0xF8, /* 6 0b11111100 */ 0xFC, /* 7 0b11111110 */ 0xFE }; uint8_t markbit[8] = { /* 0 0b10000000 */ 0x80, /* 1 0b01000000 */ 0x40, /* 2 0b00100000 */ 0x20, /* 3 0b00010000 */ 0x10, /* 4 0b00001000 */ 0x08, /* 5 0b00000100 */ 0x04, /* 6 0b00000010 */ 0x02, /* 7 0b00000001 */ 0x01 }; if (!length) return shaSuccess; if (!context) return shaNull; if (context->Computed || (length >= 8) || (length == 0)) { context->Corrupted = shaStateError; return shaStateError; } if (context->Corrupted) return context->Corrupted; SHA1AddLength(context, length); SHA1Finalize(context, (uint8_t)((message_bits & masks[length]) | markbit[length])); return shaSuccess; } /* * SHA1Result * * Description: * This function will return the 160-bit message digest into the * Message_Digest array provided by the caller. * NOTE: The first octet of hash is stored in the 0th element, * the last octet of hash in the 19th element. * * Parameters: * context: [in/out] * The context to use to calculate the SHA-1 hash. * Message_Digest: [out] * Where the digest is returned. * * Returns: * sha Error Code. * */ int SHA1Result(SHA1Context *context, uint8_t Message_Digest[SHA1HashSize]) { int i; if (!context || !Message_Digest) return shaNull; if (context->Corrupted) return context->Corrupted; if (!context->Computed) SHA1Finalize(context, 0x80); for (i = 0; i < SHA1HashSize; ++i) Message_Digest[i] = (uint8_t)(context->Intermediate_Hash[i >> 2] >> 8 * (3 - (i & 0x03))); return shaSuccess; } /* * SHA1Finalize * * Description: * This helper function finishes off the digest calculations. * * Parameters: * context: [in/out] * The SHA context to update * Pad_Byte: [in] * The last byte to add to the digest before the 0-padding * and length. This will contain the last bits of the message * followed by another single bit. If the message was an * exact multiple of 8-bits long, Pad_Byte will be 0x80. * * Returns: * sha Error Code. * */ static void SHA1Finalize(SHA1Context *context, uint8_t Pad_Byte) { int i; SHA1PadMessage(context, Pad_Byte); /* message may be sensitive, clear it out */ for (i = 0; i < SHA1_Message_Block_Size; ++i) context->Message_Block[i] = 0; context->Length_Low = 0; /* and clear length */ context->Length_High = 0; context->Computed = 1; } /* * SHA1PadMessage * * Description: * According to the standard, the message must be padded to an * even 512 bits. The first padding bit must be a '1'. The last * 64 bits represent the length of the original message. All bits * in between should be 0. This helper function will pad the * message according to those rules by filling the Message_Block * array accordingly. When it returns, it can be assumed that the * message digest has been computed. * * Parameters: * context: [in/out] * The context to pad * Pad_Byte: [in] * The last byte to add to the digest before the 0-padding * and length. This will contain the last bits of the message * followed by another single bit. If the message was an * exact multiple of 8-bits long, Pad_Byte will be 0x80. * * Returns: * Nothing. */ static void SHA1PadMessage(SHA1Context *context, uint8_t Pad_Byte) { /* * Check to see if the current message block is too small to hold * the initial padding bits and length. If so, we will pad the * block, process it, and then continue padding into a second * block. */ if (context->Message_Block_Index >= (SHA1_Message_Block_Size - 8)) { context->Message_Block[context->Message_Block_Index++] = Pad_Byte; while (context->Message_Block_Index < SHA1_Message_Block_Size) context->Message_Block[context->Message_Block_Index++] = 0; SHA1ProcessMessageBlock(context); } else context->Message_Block[context->Message_Block_Index++] = Pad_Byte; while (context->Message_Block_Index < (SHA1_Message_Block_Size - 8)) context->Message_Block[context->Message_Block_Index++] = 0; /* * Store the message length as the last 8 octets */ context->Message_Block[56] = (uint8_t)(context->Length_High >> 24); context->Message_Block[57] = (uint8_t)(context->Length_High >> 16); context->Message_Block[58] = (uint8_t)(context->Length_High >> 8); context->Message_Block[59] = (uint8_t)(context->Length_High); context->Message_Block[60] = (uint8_t)(context->Length_Low >> 24); context->Message_Block[61] = (uint8_t)(context->Length_Low >> 16); context->Message_Block[62] = (uint8_t)(context->Length_Low >> 8); context->Message_Block[63] = (uint8_t)(context->Length_Low); SHA1ProcessMessageBlock(context); } /* * SHA1ProcessMessageBlock * * Description: * This helper function will process the next 512 bits of the * message stored in the Message_Block array. * * Parameters: * None. * * Returns: * Nothing. * * Comments: * Many of the variable names in this code, especially the * single character names, were used because those were the * names used in the publication. */ static void SHA1ProcessMessageBlock(SHA1Context *context) { /* Constants defined in FIPS-180-2, section 4.2.1 */ const uint32_t K[4] = { 0x5A827999, 0x6ED9EBA1, 0x8F1BBCDC, 0xCA62C1D6 }; int t; /* Loop counter */ uint32_t temp; /* Temporary word value */ uint32_t W[80]; /* Word sequence */ uint32_t A, B, C, D, E; /* Word buffers */ /* * Initialize the first 16 words in the array W */ for (t = 0; t < 16; t++) { W[t] = ((uint32_t)context->Message_Block[t * 4]) << 24; W[t] |= ((uint32_t)context->Message_Block[t * 4 + 1]) << 16; W[t] |= ((uint32_t)context->Message_Block[t * 4 + 2]) << 8; W[t] |= ((uint32_t)context->Message_Block[t * 4 + 3]); } for (t = 16; t < 80; t++) W[t] = SHA1_ROTL(1, W[t - 3] ^ W[t - 8] ^ W[t - 14] ^ W[t - 16]); A = context->Intermediate_Hash[0]; B = context->Intermediate_Hash[1]; C = context->Intermediate_Hash[2]; D = context->Intermediate_Hash[3]; E = context->Intermediate_Hash[4]; for (t = 0; t < 20; t++) { temp = SHA1_ROTL(5, A) + SHA_Ch(B, C, D) + E + W[t] + K[0]; E = D; D = C; C = SHA1_ROTL(30, B); B = A; A = temp; } for (t = 20; t < 40; t++) { temp = SHA1_ROTL(5, A) + SHA_Parity(B, C, D) + E + W[t] + K[1]; E = D; D = C; C = SHA1_ROTL(30, B); B = A; A = temp; } for (t = 40; t < 60; t++) { temp = SHA1_ROTL(5, A) + SHA_Maj(B, C, D) + E + W[t] + K[2]; E = D; D = C; C = SHA1_ROTL(30, B); B = A; A = temp; } for (t = 60; t < 80; t++) { temp = SHA1_ROTL(5, A) + SHA_Parity(B, C, D) + E + W[t] + K[3]; E = D; D = C; C = SHA1_ROTL(30, B); B = A; A = temp; } context->Intermediate_Hash[0] += A; context->Intermediate_Hash[1] += B; context->Intermediate_Hash[2] += C; context->Intermediate_Hash[3] += D; context->Intermediate_Hash[4] += E; context->Message_Block_Index = 0; }