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sha1: cleanup and fix test cases

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This commit is contained in:
Danny Robson 2014-04-16 18:35:09 +10:00
parent 21b2b2368c
commit fc935863ef
3 changed files with 80 additions and 75 deletions
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127
hash/sha1.cpp
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@ -20,6 +20,7 @@
#include "sha1.hpp" #include "sha1.hpp"
#include "bitwise.hpp" #include "bitwise.hpp"
#include "debug.hpp"
#include "endian.hpp" #include "endian.hpp"
#include "types.hpp" #include "types.hpp"
#include "types/casts.hpp" #include "types/casts.hpp"
@ -64,15 +65,16 @@ static const uint32_t K_40 = 0x8F1BBCDC;
static const uint32_t K_60 = 0xCA62C1D6; static const uint32_t K_60 = 0xCA62C1D6;
static const uint32_t DEFAULT_H0 = 0x67452301; static const uint32_t DEFAULT_H[] = {
static const uint32_t DEFAULT_H1 = 0xEFCDAB89; 0x67452301,
static const uint32_t DEFAULT_H2 = 0x98BADCFE; 0xEFCDAB89,
static const uint32_t DEFAULT_H3 = 0x10325476; 0x98BADCFE,
static const uint32_t DEFAULT_H4 = 0xC3D2E1F0; 0x10325476,
0xC3D2E1F0
};
static const size_t BLOCK_SIZE = 16;
static const size_t BLOCK_WORDS = 16;
static const size_t BLOCK_BYTES = BLOCK_WORDS * sizeof (uint32_t);
SHA1::SHA1() SHA1::SHA1()
{ {
@ -83,53 +85,49 @@ SHA1::SHA1()
void void
SHA1::reset (void) { SHA1::reset (void) {
total = 0; total = 0;
H[0] = DEFAULT_H0;
H[1] = DEFAULT_H1;
H[2] = DEFAULT_H2;
H[3] = DEFAULT_H3;
H[4] = DEFAULT_H4;
std::fill (begin (W), end (W), 0);
state = READY; state = READY;
std::copy (std::begin (DEFAULT_H), std::end (DEFAULT_H), H);
} }
void void
SHA1::update (const uint8_t *data, size_t size) { SHA1::update (const uint8_t *data, size_t size) {
assert (state == READY); CHECK_EQ (state, READY);
assert (numeric_limits<decltype(total)>::max () - total >= size); CHECK_GE (numeric_limits<decltype(total)>::max () - total, size);
while (size > 0) { while (size > 0) {
size_t offset = total % BLOCK_SIZE; // Copy the data into the remaining available buffer slots
size_t tocopy = std::min (BLOCK_SIZE - offset, size); const size_t offset = total % BLOCK_BYTES;
const size_t chunk = std::min (BLOCK_BYTES - offset, size);
for (size_t i = 0; i < tocopy; ++i) { std::copy (data, data + chunk, c + offset);
size_t octet = sizeof(W[0]) - (offset + i) % sizeof (W[0]);
size_t index = (offset / sizeof (W[0]) + i) / sizeof (W[0]);
size_t shift = (octet - 1) * 8u; total += chunk;
uint32_t byte = *data++;
W[index] |= byte << shift; // Attempt to process if full
} if (total % BLOCK_BYTES == 0)
total += tocopy;
if (total % BLOCK_SIZE == 0) {
process (); process ();
std::fill (begin (W), end (W), 0);
} size -= chunk;
size -= tocopy; data += chunk;
} }
} }
void void
SHA1::process (void) { SHA1::process (void) {
// Shuffle the work buffer a bit and initialise the state variables CHECK_EQ (total % BLOCK_BYTES, 0);
// Byteswap the raw input we have buffered ready for arithmetic
std::transform (std::begin (W),
std::end (W),
std::begin (W),
[] (uint32_t x) {
return ntoh (x);
});
// Initialise the work buffer and the state variables
for (size_t t = 16; t < 80; ++t) for (size_t t = 16; t < 80; ++t)
W[t] = rotatel (W[t - 3] ^ W[t - 8] ^ W[t - 14] ^ W[t - 16], 1); W[t] = rotatel (W[t - 3] ^ W[t - 8] ^ W[t - 14] ^ W[t - 16], 1);
@ -154,7 +152,7 @@ SHA1::process (void) {
for (size_t t = 40; t < 60; ++t) ROTATE_STATE(40); for (size_t t = 40; t < 60; ++t) ROTATE_STATE(40);
for (size_t t = 60; t < 80; ++t) ROTATE_STATE(60); for (size_t t = 60; t < 80; ++t) ROTATE_STATE(60);
// Save out the intermediate hash again // Update the resulting hash state
H[0] += A; H[0] += A;
H[1] += B; H[1] += B;
H[2] += C; H[2] += C;
@ -165,34 +163,37 @@ SHA1::process (void) {
void void
SHA1::finish (void) { SHA1::finish (void) {
size_t index = (total / sizeof (W[0])) % BLOCK_SIZE; size_t offset = total % BLOCK_BYTES;
size_t octet = sizeof (W[0]) - total % sizeof (W[0]) - 1; size_t used = total * 8;
W[index] |= 0x80u << octet * 8u; // Append a single one bit
if (index >= BLOCK_SIZE - 2) { c[offset++] = 0x80;
W[elems(W) - 2] = 0; total += 1;
W[elems(W) - 1] = 0;
process(); // Zero fill if we can't append length
std::fill (begin (W), end (W), 0); size_t chunk = BLOCK_BYTES - offset;
index = 0; if (chunk < sizeof (total)) {
} else { std::fill_n (c + offset, chunk, 0);
++index; total += chunk;
process ();
chunk = BLOCK_BYTES;
offset = 0;
} }
std::fill (begin (W) + index, end (W), 0); // Zero fill and append total length
std::fill_n (c + offset, chunk - sizeof (total), 0);
c[BLOCK_BYTES - 1] = used & 0xFF; used >>= 8;
c[BLOCK_BYTES - 2] = used & 0xFF; used >>= 8;
c[BLOCK_BYTES - 3] = used & 0xFF; used >>= 8;
c[BLOCK_BYTES - 4] = used & 0xFF; used >>= 8;
c[BLOCK_BYTES - 5] = used & 0xFF; used >>= 8;
c[BLOCK_BYTES - 6] = used & 0xFF; used >>= 8;
c[BLOCK_BYTES - 7] = used & 0xFF; used >>= 8;
c[BLOCK_BYTES - 8] = used & 0xFF; used >>= 8;
union { total += chunk;
uint32_t full;
uint8_t part[4];
} swapper;
swapper.full = 0;
swapper.part[3] = uint8_t(total);
total *= 8;
W[BLOCK_SIZE - 2] = 0x00000000;
W[BLOCK_SIZE - 1] = total << 24;
process (); process ();
state = FINISHED; state = FINISHED;
@ -201,7 +202,7 @@ SHA1::finish (void) {
SHA1::digest_t SHA1::digest_t
SHA1::digest (void) const { SHA1::digest (void) const {
assert (state == FINISHED); CHECK_EQ (state, FINISHED);
return { { return { {
size_cast<uint8_t> ((H[0] >> 24u) & 0xFF), size_cast<uint8_t> ((H[0] >> 24u) & 0xFF),

2
hash/sha1.hpp
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@ -53,7 +53,7 @@ namespace util {
union { union {
uint8_t c[16*4+64*4]; uint8_t c[16*4+64*4];
uint32_t W[16+64]; uint32_t W[16 +64 ];
}; };
}; };
} }

26
test/sha1.cpp
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@ -1,5 +1,6 @@
#include "../hash/sha1.hpp" #include "../hash/sha1.hpp"
#include "../debug.hpp"
#include "../types.hpp" #include "../types.hpp"
#include <cstdlib> #include <cstdlib>
@ -38,21 +39,22 @@ main (int, char**) {
0x4A, 0xA1, 0xF9, 0x51, 0x29, 0xE5, 0xE5, 0x46, 0x70, 0xF1 } } 0x4A, 0xA1, 0xF9, 0x51, 0x29, 0xE5, 0xE5, 0x46, 0x70, 0xF1 } }
}, },
{ "a", // 1'000'000 * 'a'
{ { 0x34, 0xAA, 0x97, 0x3C, 0xD4, 0xC4, 0xDA, 0xA4, 0xF6, 0x1E, //{ "a",
0xEB, 0x2B, 0xDB, 0xAD, 0x27, 0x31, 0x65, 0x34, 0x01, 0x6F } } // { { 0x34, 0xAA, 0x97, 0x3C, 0xD4, 0xC4, 0xDA, 0xA4, 0xF6, 0x1E,
}, // 0xEB, 0x2B, 0xDB, 0xAD, 0x27, 0x31, 0x65, 0x34, 0x01, 0x6F } }
//},
{ "0123456701234567012345670123456701234567012345670123456701234567", // 80 repetitions of 01234567
{ { 0xDE, 0xA3, 0x56, 0xA2, 0xCD, 0xDD, 0x90, 0xC7, 0xA7, 0xEC, //{ "0123456701234567012345670123456701234567012345670123456701234567",
0xED, 0xC5, 0xEB, 0xB5, 0x63, 0x93, 0x4F, 0x46, 0x04, 0x52 } } // { { 0xDE, 0xA3, 0x56, 0xA2, 0xCD, 0xDD, 0x90, 0xC7, 0xA7, 0xEC,
} // 0xED, 0xC5, 0xEB, 0xB5, 0x63, 0x93, 0x4F, 0x46, 0x04, 0x52 } }
//}
}; };
for (size_t i = 0; i < elems (TESTS); ++i) { for (auto i: TESTS) {
util::hash::SHA1 obj; util::hash::SHA1 obj;
obj.update (reinterpret_cast<const uint8_t*> (TESTS[i].input), obj.update (reinterpret_cast<const uint8_t*> (i.input), strlen (i.input));
strlen (TESTS[i].input));
obj.finish (); obj.finish ();
for (uint8_t c: obj.digest ()) { for (uint8_t c: obj.digest ()) {
@ -62,6 +64,8 @@ main (int, char**) {
std::cout << std::hex << hi << lo << " "; std::cout << std::hex << hi << lo << " ";
} }
std::cout << "\n"; std::cout << "\n";
CHECK (obj.digest () == i.output);
} }
return 0; return 0;