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-rw-r--r--src/libsha2/digest.c175
-rw-r--r--src/libsha2/digest.h4
-rw-r--r--src/libsha2/state.c4
-rw-r--r--src/libsha2/state.h28
4 files changed, 189 insertions, 22 deletions
diff --git a/src/libsha2/digest.c b/src/libsha2/digest.c
index 5cf0f03..07f5c4a 100644
--- a/src/libsha2/digest.c
+++ b/src/libsha2/digest.c
@@ -17,18 +17,136 @@
* along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
#include "digest.h"
+#include <alloca.h>
+#include <string.h>
/**
+ * Unified implementation (what can unified without performance impact)
+ * of the chunk processing for all SHA-2 functions
+ *
+ * @param A Wordsize-dependent constant, take a look at the code
+ * @param B Wordsize-dependent constant, take a look at the code
+ * @param C Wordsize-dependent constant, take a look at the code
+ * @param D Wordsize-dependent constant, take a look at the code
+ * @param E Wordsize-dependent constant, take a look at the code
+ * @param F Wordsize-dependent constant, take a look at the code
+ * @param G Wordsize-dependent constant, take a look at the code
+ * @param H Wordsize-dependent constant, take a look at the code
+ * @param I Wordsize-dependent constant, take a look at the code
+ * @param J Wordsize-dependent constant, take a look at the code
+ * @param K Wordsize-dependent constant, take a look at the code
+ * @param L Wordsize-dependent constant, take a look at the code
+ * @param WORD_T `__typeof()` on any wordsize-dependent variable, with exact size
+ * @param k Round constants
+ * @param w Words
+ * @param h Hash values
+ * @param work_h Space for temporary hash values
+ */
+#define SHA2_IMPLEMENTATION(A, B, C, D, E, F, G, H, I, J, K, L, WORD_T, k, w, h, work_h) \
+ memcpy(work_h, h, sizeof(work_h)); \
+ \
+ memset(w, 0, 16 * sizeof(*(w))); \
+ for (i = 0; i < 16; i++) \
+ for (j = 0; j < sizeof(WORD_T); j++) \
+ w[i] |= ((WORD_T)(state->chunk[(i + 1) * sizeof(WORD_T) - j - 1])) << (j << 3); \
+ \
+ for (i = 16; i < sizeof(k) / sizeof(*(k)); i++) \
+ { \
+ w[i] = w[i - 16] + w[i - 7]; \
+ w[i] += ROTR(w[i - 15], A) ^ ROTR(w[i - 15], B) ^ (w[i - 15] >> (C)); \
+ w[i] += ROTR(w[i - 2], D) ^ ROTR(w[i - 2], E) ^ (w[i - 2] >> (F)); \
+ } \
+ \
+ for (i = 0; i < sizeof(k) / sizeof(*(k)); i++) \
+ { \
+ s1 = (work_h[4] & work_h[5]) ^ (work_h[6] & ~(work_h[4])); \
+ s1 += work_h[7] + k[i] + w[i]; \
+ s0 = (work_h[0] & work_h[1]) ^ (work_h[0] & work_h[2]) ^ (work_h[1] & work_h[2]); \
+ s1 += ROTR(work_h[4], G) ^ ROTR(work_h[4], H) ^ ROTR(work_h[4], I); \
+ s0 += ROTR(work_h[0], J) ^ ROTR(work_h[0], K) ^ ROTR(work_h[0], L); \
+ \
+ memmove(work_h + 1, work_h, 7 * sizeof(*(work_h))); \
+ work_h[4] += s1; \
+ work_h[0] = s1 + s0; \
+ } \
+ \
+ for (i = 0; i < 8; i++) \
+ h[i] += work_h[i]
+
+
+
+/**
+ * Process a chunk using SHA-256
+ *
+ * @param state The hashing state
+ */
+__attribute__((nonnull, nothrow))
+static void process256(libsha2_state_t* restrict state)
+{
+ uint32_t s0, s1;
+ size_t i, j;
+#define ROTR(X, N) (((X) >> (N)) | ((X) << ((sizeof(uint32_t) * 8) - (N))))
+ SHA2_IMPLEMENTATION(7, 18, 3, 17, 19, 10, 6, 11, 25, 2, 13, 22, uint32_t,
+ state->k.b32, state->w.b32, state->h.b32, state->work_h.b32);
+#undef ROTR
+}
+
+
+/**
+ * Process a chunk using SHA-512
+ *
+ * @param state The hashing state
+ */
+__attribute__((nonnull, nothrow))
+static void process512(libsha2_state_t* restrict state)
+{
+ uint64_t s0, s1;
+ size_t i, j;
+#define ROTR(X, N) (((X) >> (N)) | ((X) << ((sizeof(uint64_t) * 8) - (N))))
+ SHA2_IMPLEMENTATION(1, 8, 7, 19, 61, 6, 14, 18, 41, 28, 34, 39, uint64_t,
+ state->k.b64, state->w.b64, state->h.b64, state->work_h.b64);
+#undef ROTR
+}
+
+
+/**
* Absorb more of the message
*
* @param state The hashing state
- * @param message The message
+ * @param message The message, in bits, must be equivalent to 0 modulus 8
* @param msglen The length of the message
*/
void libsha2_update(libsha2_state_t* restrict state, const char* restrict message, size_t msglen)
{
+ size_t n, off, mlen;
+
+ msglen /= 8;
+ mlen = state->message_size / 8;
+
+ while (msglen)
+ {
+ off = mlen % state->chunk_size;
+ n = state->chunk_size - off;
+ n = n < msglen ? n : msglen;
+ memcpy(state->chunk + off, message, n);
+ if (off + n == state->chunk_size)
+ switch (state->algorithm)
+ {
+ case LIBSHA2_224:
+ case LIBSHA2_256:
+ process256(state);
+ break;
+
+ default:
+ process512(state);
+ break;
+ }
+ message += n, mlen += n, msglen -= n;
+ }
+
+ state->message_size = mlen * 8;
}
@@ -36,11 +154,64 @@ void libsha2_update(libsha2_state_t* restrict state, const char* restrict messag
* Absorb the last part of the message and output a hash
*
* @param state The hashing state
- * @param message The message
+ * @param message The message, in bits
* @param msglen The length of the message, zero if there is nothing more to absorb
* @param output The output buffer for the hash
*/
void libsha2_digest(libsha2_state_t* restrict state, const char* restrict message, size_t msglen, char* output)
{
+ char* appendix;
+ size_t i, j, k, n;
+
+ if (msglen & ~7)
+ {
+ libsha2_update(state, message, msglen & ~7);
+ message += msglen & ~7;
+ msglen &= 7;
+ }
+
+ k = 8 * state->chunk_size;
+ n = state->chunk_size + 8;
+ n = (k + (n % k)) % k;
+ n = n / 8 - 1;
+
+ appendix = state->appendix;
+ if (msglen)
+ {
+ j = 7 - msglen;
+ *appendix = *message;
+ *appendix |= 1 << j;
+ *appendix &= ~((1 << j) - 1);
+ }
+ else
+ *appendix = (unsigned char)128;
+
+ k = state->message_size + msglen;
+ i = state->chunk_size / 8;
+ appendix += n + i - 1;
+ for (i = i < sizeof(size_t) ? i : sizeof(size_t); i--;)
+ *(appendix - i) = (unsigned char)((k >> (i * 8)) & 255);
+
+ n += state->chunk_size;
+ libsha2_update(state, state->appendix, n);
+
+ n = libsha2_algorithm_output_size(state->algorithm);
+ switch (state->algorithm)
+ {
+ case LIBSHA2_224:
+ case LIBSHA2_256:
+ for (i = 0; i < 8; i++)
+ for (j = 0; j < (state->chunk_size / 16); j++)
+ if (k = (i + 1) * (state->chunk_size / 16) - j - 1, k < n)
+ output[k] = (char)((state->h.b32[i] >> (8 * j)) & 255);
+ break;
+
+ default:
+ for (i = 0; i < 8; i++)
+ for (j = 0; j < (state->chunk_size / 16); j++)
+ if (k = (i + 1) * (state->chunk_size / 16) - j - 1, k < n)
+ output[k] = (char)((state->h.b64[i] >> (8 * j)) & 255);
+ break;
+ }
}
diff --git a/src/libsha2/digest.h b/src/libsha2/digest.h
index 47b3414..be81f90 100644
--- a/src/libsha2/digest.h
+++ b/src/libsha2/digest.h
@@ -27,7 +27,7 @@
* Absorb more of the message
*
* @param state The hashing state
- * @param message The message
+ * @param message The message, in bits, must be equivalent to 0 modulus 8
* @param msglen The length of the message
*/
__attribute__((nonnull, nothrow))
@@ -37,7 +37,7 @@ void libsha2_update(libsha2_state_t* restrict state, const char* restrict messag
* Absorb the last part of the message and output a hash
*
* @param state The hashing state
- * @param message The message
+ * @param message The message, in bits
* @param msglen The length of the message, zero if there is nothing more to absorb
* @param output The output buffer for the hash
*/
diff --git a/src/libsha2/state.c b/src/libsha2/state.c
index 0a7a5b1..e907cec 100644
--- a/src/libsha2/state.c
+++ b/src/libsha2/state.c
@@ -95,17 +95,19 @@ int libsha2_state_initialise(libsha2_state_t* restrict state, libsha2_algorithm_
return errno = EINVAL, -1;
}
- /* Set round constants. */
+ /* Set round constants, and chunk size. */
switch (algorithm)
{
case LIBSHA2_224:
case LIBSHA2_256:
for (i = 0; i < 64; i++)
state->k.b32[i] = (uint32_t)(ROUND_CONSTANTS[i] >> 32);
+ state->chunk_size = 64;
break;
default:
memcpy(state->k.b64, ROUND_CONSTANTS, sizeof(ROUND_CONSTANTS));
+ state->chunk_size = 128;
break;
}
diff --git a/src/libsha2/state.h b/src/libsha2/state.h
index c290186..1dfd4be 100644
--- a/src/libsha2/state.h
+++ b/src/libsha2/state.h
@@ -148,27 +148,21 @@ typedef struct libsha2_state
} work_h;
/**
- * Space for chunks to process
+ * Space for chunks to process, limited
+ * to 64 bytes on 32-bit algorithms
*/
- union
- {
- /**
- * For 32-bit algorithms
- */
- unsigned char b32[64];
-
- /**
- * For 64-bit algorithms
- */
- unsigned char b64[128];
-
- } chunk;
+ unsigned char chunk[128];
+
+ /**
+ * Space for storing the last bits and
+ * the padding
+ */
+ char appendix[256];
/**
- * Output buffer, required because
- * some algorithms truncate the output
+ * The size of the chunks, in bytes
*/
- char output[64];
+ size_t chunk_size;
/**
* The algorithm that is used
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-09-19 16:59:29 +0000