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Diffstat (limited to 'src/teeny-sha1.c')
-rw-r--r--[l---------] | src/teeny-sha1.c | 207 |
1 files changed, 206 insertions, 1 deletions
diff --git a/src/teeny-sha1.c b/src/teeny-sha1.c index 4208eb3..69e5cc9 120000..100644 --- a/src/teeny-sha1.c +++ b/src/teeny-sha1.c @@ -1 +1,206 @@ -../teeny-sha1/teeny-sha1.c
\ No newline at end of file +/** + * Cloned from https://github.com/CTrabant/teeny-sha1 + * in commit f05a2d0019e12850bb482274c1a21ae7a4fb84bd + */ + +/******************************************************************************* + * Teeny SHA-1 + * + * The below sha1digest() calculates a SHA-1 hash value for a + * specified data buffer and generates a hex representation of the + * result. This implementation is a re-forming of the SHA-1 code at + * https://github.com/jinqiangshou/EncryptionLibrary. + * + * Copyright (c) 2017 CTrabant + * + * License: MIT, see included LICENSE file for details. + * + * To use the sha1digest() function either copy it into an existing + * project source code file or include this file in a project and put + * the declaration (example below) in the sources files where needed. + ******************************************************************************/ + +#include <stdio.h> +#include <stdint.h> +#include <stdlib.h> +#include <string.h> + +/* Declaration: +extern int sha1digest(uint8_t *digest, char *hexdigest, const uint8_t *data, size_t databytes); +*/ + +/******************************************************************************* + * sha1digest: https://github.com/CTrabant/teeny-sha1 + * + * Calculate the SHA-1 value for supplied data buffer and generate a + * text representation in hexadecimal. + * + * Based on https://github.com/jinqiangshou/EncryptionLibrary, credit + * goes to @jinqiangshou, all new bugs are mine. + * + * @input: + * data -- data to be hashed + * databytes -- bytes in data buffer to be hashed + * + * @output: + * digest -- the result, MUST be at least 20 bytes + * hexdigest -- the result in hex, MUST be at least 41 bytes + * + * At least one of the output buffers must be supplied. The other, if not + * desired, may be set to NULL. + * + * @return: 0 on success and non-zero on error. + ******************************************************************************/ +int +sha1digest(uint8_t *digest, char *hexdigest, const uint8_t *data, size_t databytes) +{ +#define SHA1ROTATELEFT(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits)))) + + uint32_t W[80]; + uint32_t H[] = {0x67452301, + 0xEFCDAB89, + 0x98BADCFE, + 0x10325476, + 0xC3D2E1F0}; + uint32_t a; + uint32_t b; + uint32_t c; + uint32_t d; + uint32_t e; + uint32_t f = 0; + uint32_t k = 0; + + uint32_t idx; + uint32_t lidx; + uint32_t widx; + uint32_t didx = 0; + + int32_t wcount; + uint32_t temp; + uint64_t databits = ((uint64_t)databytes) * 8; + uint32_t loopcount = (databytes + 8) / 64 + 1; + uint32_t tailbytes = 64 * loopcount - databytes; + uint8_t datatail[128] = {0}; + + if (!digest && !hexdigest) + return -1; + + if (!data) + return -1; + + /* Pre-processing of data tail (includes padding to fill out 512-bit chunk): + Add bit '1' to end of message (big-endian) + Add 64-bit message length in bits at very end (big-endian) */ + datatail[0] = 0x80; + datatail[tailbytes - 8] = (uint8_t) (databits >> 56 & 0xFF); + datatail[tailbytes - 7] = (uint8_t) (databits >> 48 & 0xFF); + datatail[tailbytes - 6] = (uint8_t) (databits >> 40 & 0xFF); + datatail[tailbytes - 5] = (uint8_t) (databits >> 32 & 0xFF); + datatail[tailbytes - 4] = (uint8_t) (databits >> 24 & 0xFF); + datatail[tailbytes - 3] = (uint8_t) (databits >> 16 & 0xFF); + datatail[tailbytes - 2] = (uint8_t) (databits >> 8 & 0xFF); + datatail[tailbytes - 1] = (uint8_t) (databits >> 0 & 0xFF); + + /* Process each 512-bit chunk */ + for (lidx = 0; lidx < loopcount; lidx++) + { + /* Compute all elements in W */ + memset (W, 0, 80 * sizeof (uint32_t)); + + /* Break 512-bit chunk into sixteen 32-bit, big endian words */ + for (widx = 0; widx <= 15; widx++) + { + wcount = 24; + + /* Copy byte-per byte from specified buffer */ + while (didx < databytes && wcount >= 0) + { + W[widx] += (((uint32_t)data[didx]) << wcount); + didx++; + wcount -= 8; + } + /* Fill out W with padding as needed */ + while (wcount >= 0) + { + W[widx] += (((uint32_t)datatail[didx - databytes]) << wcount); + didx++; + wcount -= 8; + } + } + + /* Extend the sixteen 32-bit words into eighty 32-bit words, with potential optimization from: + "Improving the Performance of the Secure Hash Algorithm (SHA-1)" by Max Locktyukhin */ + for (widx = 16; widx <= 31; widx++) + { + W[widx] = SHA1ROTATELEFT ((W[widx - 3] ^ W[widx - 8] ^ W[widx - 14] ^ W[widx - 16]), 1); + } + for (widx = 32; widx <= 79; widx++) + { + W[widx] = SHA1ROTATELEFT ((W[widx - 6] ^ W[widx - 16] ^ W[widx - 28] ^ W[widx - 32]), 2); + } + + /* Main loop */ + a = H[0]; + b = H[1]; + c = H[2]; + d = H[3]; + e = H[4]; + + for (idx = 0; idx <= 79; idx++) + { + if (idx <= 19) + { + f = (b & c) | ((~b) & d); + k = 0x5A827999; + } + else if (idx >= 20 && idx <= 39) + { + f = b ^ c ^ d; + k = 0x6ED9EBA1; + } + else if (idx >= 40 && idx <= 59) + { + f = (b & c) | (b & d) | (c & d); + k = 0x8F1BBCDC; + } + else if (idx >= 60 && idx <= 79) + { + f = b ^ c ^ d; + k = 0xCA62C1D6; + } + temp = SHA1ROTATELEFT (a, 5) + f + e + k + W[idx]; + e = d; + d = c; + c = SHA1ROTATELEFT (b, 30); + b = a; + a = temp; + } + + H[0] += a; + H[1] += b; + H[2] += c; + H[3] += d; + H[4] += e; + } + + /* Store binary digest in supplied buffer */ + if (digest) + { + for (idx = 0; idx < 5; idx++) + { + digest[idx * 4 + 0] = (uint8_t) (H[idx] >> 24); + digest[idx * 4 + 1] = (uint8_t) (H[idx] >> 16); + digest[idx * 4 + 2] = (uint8_t) (H[idx] >> 8); + digest[idx * 4 + 3] = (uint8_t) (H[idx]); + } + } + + /* Store hex version of digest in supplied buffer */ + if (hexdigest) + { + snprintf (hexdigest, 41, "%08x%08x%08x%08x%08x", + H[0],H[1],H[2],H[3],H[4]); + } + + return 0; +} /* End of sha1digest() */ |