Record networking and DMA development progress

Add the current OS source tree, build scripts, system image layout, and development notes covering DMA page allocation, e1000 bring-up, net API dispatch, and DHCP work in progress.

CODE/UTSM/crypto/kdf.c

@@ -0,0 +1,19 @@
+#include <utsm/crypto.h>
+#include <utsm/drr.h>
+
+static u64 mix64(u64 x) {
+    x ^= x >> 30;
+    x *= 0xbf58476d1ce4e5b9ULL;
+    x ^= x >> 27;
+    x *= 0x94d049bb133111ebULL;
+    x ^= x >> 31;
+    return x;
+}
+
+void utsm_kdf_segment_key(uuid128_t process_uuid, uuid128_t segment_uuid, u64 key_epoch, utsm_key_material *out_key) {
+    const u64 *root = drr_get_root_key();
+    out_key->words[0] = mix64(root[0] ^ process_uuid.hi ^ segment_uuid.lo ^ key_epoch);
+    out_key->words[1] = mix64(root[1] ^ process_uuid.lo ^ segment_uuid.hi ^ (key_epoch << 1));
+    out_key->words[2] = mix64(root[2] ^ process_uuid.hi ^ segment_uuid.hi ^ (key_epoch << 7));
+    out_key->words[3] = mix64(root[3] ^ process_uuid.lo ^ segment_uuid.lo ^ (key_epoch << 13));
+}

CODE/UTSM/crypto/stream.c

@@ -0,0 +1,19 @@
+#include <utsm/crypto.h>
+#include <utsm/config.h>
+
+static u64 next_stream_word(u64 x) {
+    x ^= x << 13;
+    x ^= x >> 7;
+    x ^= x << 17;
+    return x;
+}
+
+void utsm_crypt_line(const utsm_key_material *key, u64 tweak, const u8 *in, u8 *out) {
+    u64 state = key->words[0] ^ key->words[1] ^ key->words[2] ^ key->words[3] ^ tweak;
+    for (u64 i = 0; i < UTSM_CACHE_LINE_SIZE; i += 8) {
+        state = next_stream_word(state + i + 0xa5a5a5a5a5a5a5a5ULL);
+        for (u64 j = 0; j < 8; j++) {
+            out[i + j] = in[i + j] ^ (u8)(state >> (j * 8));
+        }
+    }
+}

CODE/UTSM/crypto/tweak.c

@@ -0,0 +1,14 @@
+#include <utsm/crypto.h>
+
+static u64 mix64_tweak(u64 x) {
+    x ^= x >> 33;
+    x *= 0xff51afd7ed558ccdULL;
+    x ^= x >> 33;
+    x *= 0xc4ceb9fe1a85ec53ULL;
+    x ^= x >> 33;
+    return x;
+}
+
+u64 utsm_make_tweak(u64 tweak_seed, u64 line_index, u64 key_epoch) {
+    return mix64_tweak(tweak_seed ^ (line_index * 0x9e3779b97f4a7c15ULL) ^ (key_epoch << 32));
+}