Diff: sha224.c

Revision:

0:fa2de1b79154

Child:

15:956c6d205aa7

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sha224.c	Fri Apr 08 12:01:36 2016 -0700
@@ -0,0 +1,602 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+/*************************** sha224-256.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-224 and SHA-256 algorithms produce 224-bit and 256-bit
+*   message digests 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-224 and SHA-256 are 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-224 and SHA-256 are designed to work with messages less
+*   than 2^64 bits long. This implementation uses SHA224/256Input()
+*   to hash the bits that are a multiple of the size of an 8-bit
+*   character, and then uses SHA224/256FinalBits() 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 SHA shift, rotate left and rotate right macro */
+#define SHA256_SHR(bits,word)      ((word) >> (bits))
+#define SHA256_ROTL(bits,word)                         \
+  (((word) << (bits)) | ((word) >> (32-(bits))))
+#define SHA256_ROTR(bits,word)                         \
+  (((word) >> (bits)) | ((word) << (32-(bits))))
+
+/* Define the SHA SIGMA and sigma macros */
+#define SHA256_SIGMA0(word)   \
+  (SHA256_ROTR( 2,word) ^ SHA256_ROTR(13,word) ^ SHA256_ROTR(22,word))
+#define SHA256_SIGMA1(word)   \
+  (SHA256_ROTR( 6,word) ^ SHA256_ROTR(11,word) ^ SHA256_ROTR(25,word))
+#define SHA256_sigma0(word)   \
+  (SHA256_ROTR( 7,word) ^ SHA256_ROTR(18,word) ^ SHA256_SHR( 3,word))
+#define SHA256_sigma1(word)   \
+  (SHA256_ROTR(17,word) ^ SHA256_ROTR(19,word) ^ SHA256_SHR(10,word))
+
+/*
+* add "length" to the length
+*/
+static uint32_t addTemp;
+#define SHA224_256AddLength(context, length)               \
+  (addTemp = (context)->Length_Low, (context)->Corrupted = \
+    (((context)->Length_Low += (length)) < addTemp) &&     \
+    (++(context)->Length_High == 0) ? 1 : 0)
+
+/* Local Function Prototypes */
+static void SHA224_256Finalize(SHA256Context *context,
+    uint8_t Pad_Byte);
+static void SHA224_256PadMessage(SHA256Context *context,
+    uint8_t Pad_Byte);
+static void SHA224_256ProcessMessageBlock(SHA256Context *context);
+static int SHA224_256Reset(SHA256Context *context, uint32_t *H0);
+static int SHA224_256ResultN(SHA256Context *context,
+    uint8_t Message_Digest[], int HashSize);
+
+/* Initial Hash Values: FIPS-180-2 Change Notice 1 */
+static uint32_t SHA224_H0[SHA256HashSize / 4] = {
+    0xC1059ED8, 0x367CD507, 0x3070DD17, 0xF70E5939,
+    0xFFC00B31, 0x68581511, 0x64F98FA7, 0xBEFA4FA4
+};
+
+/* Initial Hash Values: FIPS-180-2 section 5.3.2 */
+static uint32_t SHA256_H0[SHA256HashSize / 4] = {
+    0x6A09E667, 0xBB67AE85, 0x3C6EF372, 0xA54FF53A,
+    0x510E527F, 0x9B05688C, 0x1F83D9AB, 0x5BE0CD19
+};
+
+/*
+* SHA224Reset
+*
+* Description:
+*   This function will initialize the SHA384Context in preparation
+*   for computing a new SHA224 message digest.
+*
+* Parameters:
+*   context: [in/out]
+*     The context to reset.
+*
+* Returns:
+*   sha Error Code.
+*/
+int SHA224Reset(SHA224Context *context)
+{
+    return SHA224_256Reset(context, SHA224_H0);
+}
+
+/*
+* SHA224Input
+*
+* 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 SHA224Input(SHA224Context *context, const uint8_t *message_array,
+    unsigned int length)
+{
+    return SHA256Input(context, message_array, length);
+}
+
+/*
+* SHA224FinalBits
+*
+* 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 SHA224FinalBits(SHA224Context *context,
+    const uint8_t message_bits, unsigned int length)
+{
+    return SHA256FinalBits(context, message_bits, length);
+}
+
+/*
+* SHA224Result
+*
+* Description:
+*   This function will return the 224-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 28th element.
+*
+* Parameters:
+*   context: [in/out]
+*     The context to use to calculate the SHA hash.
+*   Message_Digest: [out]
+*     Where the digest is returned.
+*
+* Returns:
+*   sha Error Code.
+*/
+int SHA224Result(SHA224Context *context,
+    uint8_t Message_Digest[SHA224HashSize])
+{
+    return SHA224_256ResultN(context, Message_Digest, SHA224HashSize);
+}
+
+/*
+* SHA256Reset
+*
+* Description:
+*   This function will initialize the SHA256Context in preparation
+*   for computing a new SHA256 message digest.
+*
+* Parameters:
+*   context: [in/out]
+*     The context to reset.
+*
+* Returns:
+*   sha Error Code.
+*/
+int SHA256Reset(SHA256Context *context)
+{
+    return SHA224_256Reset(context, SHA256_H0);
+}
+
+/*
+* SHA256Input
+*
+* 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 SHA256Input(SHA256Context *context, const uint8_t *message_array,
+    unsigned int 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 (!SHA224_256AddLength(context, 8) &&
+            (context->Message_Block_Index == SHA256_Message_Block_Size))
+            SHA224_256ProcessMessageBlock(context);
+
+        message_array++;
+    }
+
+    return shaSuccess;
+
+}
+
+/*
+* SHA256FinalBits
+*
+* 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 SHA256FinalBits(SHA256Context *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;
+
+    SHA224_256AddLength(context, length);
+    SHA224_256Finalize(context, (uint8_t)
+        ((message_bits & masks[length]) | markbit[length]));
+
+    return shaSuccess;
+}
+
+/*
+* SHA256Result
+*
+* Description:
+*   This function will return the 256-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 32nd element.
+*
+* Parameters:
+*   context: [in/out]
+*     The context to use to calculate the SHA hash.
+*   Message_Digest: [out]
+*     Where the digest is returned.
+*
+* Returns:
+*   sha Error Code.
+*/
+int SHA256Result(SHA256Context *context, uint8_t Message_Digest[])
+{
+        return SHA224_256ResultN(context, Message_Digest, SHA256HashSize);
+}
+
+/*
+* SHA224_256Finalize
+*
+* 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 SHA224_256Finalize(SHA256Context *context,
+    uint8_t Pad_Byte)
+{
+    int i;
+    SHA224_256PadMessage(context, Pad_Byte);
+    /* message may be sensitive, so clear it out */
+    for (i = 0; i < SHA256_Message_Block_Size; ++i)
+        context->Message_Block[i] = 0;
+    context->Length_Low = 0;  /* and clear length */
+    context->Length_High = 0;
+    context->Computed = 1;
+}
+
+/*
+* SHA224_256PadMessage
+*
+* 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 SHA224_256PadMessage(SHA256Context *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 >= (SHA256_Message_Block_Size - 8)) {
+        context->Message_Block[context->Message_Block_Index++] = Pad_Byte;
+        while (context->Message_Block_Index < SHA256_Message_Block_Size)
+            context->Message_Block[context->Message_Block_Index++] = 0;
+        SHA224_256ProcessMessageBlock(context);
+    }
+    else
+        context->Message_Block[context->Message_Block_Index++] = Pad_Byte;
+
+    while (context->Message_Block_Index < (SHA256_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);
+
+    SHA224_256ProcessMessageBlock(context);
+}
+
+/*
+* SHA224_256ProcessMessageBlock
+*
+* Description:
+*   This function will process the next 512 bits of the message
+*   stored in the Message_Block array.
+*
+* Parameters:
+*   context: [in/out]
+*     The SHA context to update
+*
+* 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 SHA224_256ProcessMessageBlock(SHA256Context *context)
+{
+    /* Constants defined in FIPS-180-2, section 4.2.2 */
+    static const uint32_t K[64] = {
+        0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b,
+        0x59f111f1, 0x923f82a4, 0xab1c5ed5, 0xd807aa98, 0x12835b01,
+        0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7,
+        0xc19bf174, 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
+        0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da, 0x983e5152,
+        0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147,
+        0x06ca6351, 0x14292967, 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc,
+        0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
+        0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819,
+        0xd6990624, 0xf40e3585, 0x106aa070, 0x19a4c116, 0x1e376c08,
+        0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f,
+        0x682e6ff3, 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
+        0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
+    };
+    int        t, t4;                   /* Loop counter */
+    uint32_t   temp1, temp2;            /* Temporary word value */
+    uint32_t   W[64];                   /* Word sequence */
+    uint32_t   A, B, C, D, E, F, G, H;  /* Word buffers */
+
+    /*
+    * Initialize the first 16 words in the array W
+    */
+    for (t = t4 = 0; t < 16; t++, t4 += 4)
+        W[t] = (((uint32_t)context->Message_Block[t4]) << 24) |
+        (((uint32_t)context->Message_Block[t4 + 1]) << 16) |
+        (((uint32_t)context->Message_Block[t4 + 2]) << 8) |
+        (((uint32_t)context->Message_Block[t4 + 3]));
+
+    for (t = 16; t < 64; t++)
+        W[t] = SHA256_sigma1(W[t - 2]) + W[t - 7] +
+        SHA256_sigma0(W[t - 15]) + 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];
+    F = context->Intermediate_Hash[5];
+    G = context->Intermediate_Hash[6];
+    H = context->Intermediate_Hash[7];
+
+    for (t = 0; t < 64; t++) {
+        temp1 = H + SHA256_SIGMA1(E) + SHA_Ch(E, F, G) + K[t] + W[t];
+        temp2 = SHA256_SIGMA0(A) + SHA_Maj(A, B, C);
+        H = G;
+        G = F;
+        F = E;
+        E = D + temp1;
+        D = C;
+        C = B;
+        B = A;
+        A = temp1 + temp2;
+    }
+
+    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->Intermediate_Hash[5] += F;
+    context->Intermediate_Hash[6] += G;
+    context->Intermediate_Hash[7] += H;
+
+    context->Message_Block_Index = 0;
+}
+
+/*
+* SHA224_256Reset
+*
+* Description:
+*   This helper function will initialize the SHA256Context in
+*   preparation for computing a new SHA256 message digest.
+*
+* Parameters:
+*   context: [in/out]
+*     The context to reset.
+*   H0
+*     The initial hash value to use.
+*
+* Returns:
+*   sha Error Code.
+*/
+static int SHA224_256Reset(SHA256Context *context, uint32_t *H0)
+{
+    if (!context)
+        return shaNull;
+
+    context->Length_Low = 0;
+    context->Length_High = 0;
+    context->Message_Block_Index = 0;
+
+    context->Intermediate_Hash[0] = H0[0];
+    context->Intermediate_Hash[1] = H0[1];
+    context->Intermediate_Hash[2] = H0[2];
+    context->Intermediate_Hash[3] = H0[3];
+    context->Intermediate_Hash[4] = H0[4];
+    context->Intermediate_Hash[5] = H0[5];
+    context->Intermediate_Hash[6] = H0[6];
+    context->Intermediate_Hash[7] = H0[7];
+
+    context->Computed = 0;
+    context->Corrupted = 0;
+
+    return shaSuccess;
+}
+
+/*
+* SHA224_256ResultN
+*
+* Description:
+*   This helper function will return the 224-bit or 256-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 28th/32nd element.
+*
+* Parameters:
+*   context: [in/out]
+*     The context to use to calculate the SHA hash.
+*   Message_Digest: [out]
+*     Where the digest is returned.
+*   HashSize: [in]
+*     The size of the hash, either 28 or 32.
+*
+* Returns:
+*   sha Error Code.
+*/
+static int SHA224_256ResultN(SHA256Context *context,
+    uint8_t Message_Digest[], int HashSize)
+{
+    int i;
+
+    if (!context || !Message_Digest)
+        return shaNull;
+
+    if (context->Corrupted)
+        return context->Corrupted;
+
+    if (!context->Computed)
+        SHA224_256Finalize(context, 0x80);
+
+    for (i = 0; i < HashSize; ++i)
+        Message_Digest[i] = (uint8_t)
+        (context->Intermediate_Hash[i >> 2] >> 8 * (3 - (i & 0x03)));
+
+    return shaSuccess;
+}
+