1 files changed, 71 insertions, 0 deletions
diff --git a/lib/liboqs/src/sig/sphincs/pqclean_sphincs-sha256-192s-simple_clean/sha256.c b/lib/liboqs/src/sig/sphincs/pqclean_sphincs-sha256-192s-simple_clean/sha256.c
new file mode 100644
index 000000000..7ffadf35a
--- /dev/null
+++ b/lib/liboqs/src/sig/sphincs/pqclean_sphincs-sha256-192s-simple_clean/sha256.c
@@ -0,0 +1,71 @@
+/* Based on the public domain implementation in
+ * crypto_hash/sha512/ref/ from http://bench.cr.yp.to/supercop.html
+ * by D. J. Bernstein */
+
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
+#include "sha2.h"
+#include "sha256.h"
+#include "utils.h"
+
+/*
+ * Compresses an address to a 22-byte sequence.
+ * This reduces the number of required SHA256 compression calls, as the last
+ * block of input is padded with at least 65 bits.
+ */
+void PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_compress_address(unsigned char *out, const uint32_t addr[8]) {
+    PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_ull_to_bytes(out,      1, addr[0]); /* drop 3 bytes of the layer field */
+    PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_ull_to_bytes(out + 1,  4, addr[2]); /* drop the highest tree address word */
+    PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_ull_to_bytes(out + 5,  4, addr[3]);
+    PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_ull_to_bytes(out + 9,  1, addr[4]); /* drop 3 bytes of the type field */
+    PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_ull_to_bytes(out + 10, 4, addr[5]);
+    PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_ull_to_bytes(out + 14, 4, addr[6]);
+    PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_ull_to_bytes(out + 18, 4, addr[7]);
+}
+
+/**
+ * Requires 'input_plus_four_bytes' to have 'inlen' + 4 bytes, so that the last
+ * four bytes can be used for the counter. Typically 'input' is merely a seed.
+ * Outputs outlen number of bytes
+ */
+void PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_mgf1(
+    unsigned char *out, unsigned long outlen,
+    unsigned char *input_plus_four_bytes, unsigned long inlen) {
+    unsigned char outbuf[PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_SHA256_OUTPUT_BYTES];
+    unsigned long i;
+
+    /* While we can fit in at least another full block of SHA256 output.. */
+    for (i = 0; (i + 1)*PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_SHA256_OUTPUT_BYTES <= outlen; i++) {
+        PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_ull_to_bytes(input_plus_four_bytes + inlen, 4, i);
+        sha256(out, input_plus_four_bytes, inlen + 4);
+        out += PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_SHA256_OUTPUT_BYTES;
+    }
+    /* Until we cannot anymore, and we fill the remainder. */
+    if (outlen > i * PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_SHA256_OUTPUT_BYTES) {
+        PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_ull_to_bytes(input_plus_four_bytes + inlen, 4, i);
+        sha256(outbuf, input_plus_four_bytes, inlen + 4);
+        memcpy(out, outbuf, outlen - i * PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_SHA256_OUTPUT_BYTES);
+    }
+}
+
+
+/**
+ * Absorb the constant pub_seed using one round of the compression function
+ * This initializes hash_state_seeded, which can then be reused in thash
+ **/
+void PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_seed_state(sha256ctx *hash_state_seeded, const unsigned char *pub_seed) {
+    uint8_t block[PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_SHA256_BLOCK_BYTES];
+    size_t i;
+
+    for (i = 0; i < PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_N; ++i) {
+        block[i] = pub_seed[i];
+    }
+    for (i = PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_N; i < PQCLEAN_SPHINCSSHA256192SSIMPLE_CLEAN_SHA256_BLOCK_BYTES; ++i) {
+        block[i] = 0;
+    }
+
+    sha256_inc_init(hash_state_seeded);
+    sha256_inc_blocks(hash_state_seeded, block, 1);
+}