feat(hints): add NewHint#28

CHANGELOG.md

@@ -2,6 +2,42 @@
 
 #### Upcoming Changes
 
+* Add missing hint on cairo_secp lib [#989]:
+
+    `BuiltinHintProcessor` now supports the following hint:
+    ```python
+        from starkware.cairo.common.cairo_secp.secp_utils import SECP_P
+        q, r = divmod(pack(ids.val, PRIME), SECP_P)
+        assert r == 0, f"verify_zero: Invalid input {ids.val.d0, ids.val.d1, ids.val.d2}."
+        ids.q = q % PRIME
+    ```
+
+* Add missing hint on cairo_secp lib [#986]:
+    `BuiltinHintProcessor` now supports the following hint:
+    ```python
+        from starkware.cairo.common.cairo_secp.secp_utils import SECP_P, pack
+        from starkware.python.math_utils import div_mod
+
+        # Compute the slope.
+        x = pack(ids.pt.x, PRIME)
+        y = pack(ids.pt.y, PRIME)
+        value = slope = div_mod(3 * x ** 2, 2 * y, SECP_P)
+    ```
+
+* Add missing hint on cairo_secp lib [#984]:
+    `BuiltinHintProcessor` now supports the following hint:
+    ```python
+        from starkware.cairo.common.cairo_secp.secp_utils import SECP_P, pack
+        from starkware.python.math_utils import div_mod
+
+        # Compute the slope.
+        x0 = pack(ids.pt0.x, PRIME)
+        y0 = pack(ids.pt0.y, PRIME)
+        x1 = pack(ids.pt1.x, PRIME)
+        y1 = pack(ids.pt1.y, PRIME)
+        value = slope = div_mod(y0 - y1, x0 - x1, SECP_P)
+    ```
+
 * Move `Memory` into `MemorySegmentManager` [#830](https://github.com/lambdaclass/cairo-rs/pull/830)
     * Structural changes:
         * Remove `memory: Memory` field from `VirtualMachine`

cairo_programs/ed25519_ec.cairo

@@ -0,0 +1,125 @@
+%builtins range_check
+
+// Source: https://github.com/NilFoundation/cairo-ed25519/blob/fee64a1a60b2e07b3b5c20df57f31d7ffcb29ac9/ed25519_ec.cairo
+
+from starkware.cairo.common.serialize import serialize_word
+from starkware.cairo.common.cairo_secp.bigint import BigInt3, UnreducedBigInt3, nondet_bigint3
+from starkware.cairo.common.cairo_secp.field import (
+    is_zero,
+    unreduced_mul,
+    unreduced_sqr,
+    verify_zero,
+)
+
+// Represents a point on the elliptic curve.
+// The zero point is represented using pt.x=0, as there is no point on the curve with this x value.
+struct EcPoint {
+    x: BigInt3,
+    y: BigInt3,
+}
+
+// Returns the slope of the elliptic curve at the given point.
+// The slope is used to compute pt + pt.
+// Assumption: pt != 0.
+func compute_doubling_slope{range_check_ptr}(pt: EcPoint) -> (slope: BigInt3) {
+    // Note that y cannot be zero: assume that it is, then pt = -pt, so 2 * pt = 0, which
+    // contradicts the fact that the size of the curve is odd.
+    %{
+        from starkware.cairo.common.cairo_secp.secp_utils import SECP_P, pack
+        from starkware.python.math_utils import div_mod
+
+        # Compute the slope.
+        x = pack(ids.pt.x, PRIME)
+        y = pack(ids.pt.y, PRIME)
+        value = slope = div_mod(3 * x ** 2, 2 * y, SECP_P)
+    %}
+    let (slope: BigInt3) = nondet_bigint3();
+
+    let (x_sqr: UnreducedBigInt3) = unreduced_sqr(pt.x);
+    let (slope_y: UnreducedBigInt3) = unreduced_mul(slope, pt.y);
+
+    verify_zero(
+        UnreducedBigInt3(
+            d0=3 * x_sqr.d0 - 2 * slope_y.d0,
+            d1=3 * x_sqr.d1 - 2 * slope_y.d1,
+            d2=3 * x_sqr.d2 - 2 * slope_y.d2,
+        ),
+    );
+
+    return (slope=slope);
+}
+
+// Returns the slope of the line connecting the two given points.
+// The slope is used to compute pt0 + pt1.
+// Assumption: pt0.x != pt1.x (mod secp256k1_prime).
+func compute_slope{range_check_ptr: felt}(pt0: EcPoint, pt1: EcPoint) -> (slope: BigInt3) {
+    %{
+        from starkware.cairo.common.cairo_secp.secp_utils import SECP_P, pack
+        from starkware.python.math_utils import div_mod
+
+        # Compute the slope.
+        x0 = pack(ids.pt0.x, PRIME)
+        y0 = pack(ids.pt0.y, PRIME)
+        x1 = pack(ids.pt1.x, PRIME)
+        y1 = pack(ids.pt1.y, PRIME)
+        value = slope = div_mod(y0 - y1, x0 - x1, SECP_P)
+    %}
+    let (slope) = nondet_bigint3();
+
+    let x_diff = BigInt3(d0=pt0.x.d0 - pt1.x.d0, d1=pt0.x.d1 - pt1.x.d1, d2=pt0.x.d2 - pt1.x.d2);
+    let (x_diff_slope: UnreducedBigInt3) = unreduced_mul(x_diff, slope);
+
+    verify_zero(
+        UnreducedBigInt3(
+            d0=x_diff_slope.d0 - pt0.y.d0 + pt1.y.d0,
+            d1=x_diff_slope.d1 - pt0.y.d1 + pt1.y.d1,
+            d2=x_diff_slope.d2 - pt0.y.d2 + pt1.y.d2,
+        ),
+    );
+
+    return (slope=slope);
+}
+
+func test_compute_double_slope{range_check_ptr: felt}() {
+    let x = BigInt3(d0=33, d1=24, d2=12412);
+    let y = BigInt3(d0=3232, d1=122, d2=31415);
+
+    let pt = EcPoint(x=x, y=y);
+
+    // Compute slope
+    let (slope) = compute_doubling_slope(pt);
+
+    assert slope = BigInt3(
+        d0=56007611085086895200895667, d1=15076814030975805918069142, d2=6556143173243739984479201
+    );
+
+    return ();
+}
+
+func test_compute_slope{range_check_ptr: felt}() {
+    let x0 = BigInt3(d0=1, d1=5, d2=10);
+    let y0 = BigInt3(d0=2, d1=4, d2=20);
+
+    let pt0 = EcPoint(x=x0, y=y0);
+
+    let x1 = BigInt3(d0=3, d1=3, d2=3);
+    let y1 = BigInt3(d0=3, d1=5, d2=22);
+
+    let pt1 = EcPoint(x=x1, y=y1);
+
+    // Compute slope
+    let (slope) = compute_slope(pt0, pt1);
+
+    assert slope = BigInt3(
+        d0=39919528597790922692721903, d1=31451568879578276714332055, d2=6756007504256943629292535
+    );
+
+    return ();
+}
+
+func main{range_check_ptr: felt}() {
+    test_compute_double_slope();
+    test_compute_slope();
+
+    return ();
+}

cairo_programs/ed25519_field.cairo

@@ -0,0 +1,66 @@
+%builtins range_check
+
+// Source: https://github.com/NilFoundation/cairo-ed25519/blob/fee64a1a60b2e07b3b5c20df57f31d7ffcb29ac9/ed25519_field.cairo
+
+from starkware.cairo.common.cairo_secp.bigint import BASE, BigInt3, UnreducedBigInt3, nondet_bigint3
+from starkware.cairo.common.cairo_secp.constants import SECP_REM
+
+// Verifies that the given unreduced value is equal to zero modulo the secp256k1 prime.
+// Completeness assumption: val's limbs are in the range (-2**210.99, 2**210.99).
+// Soundness assumption: val's limbs are in the range (-2**250, 2**250).
+func verify_zero{range_check_ptr}(val: UnreducedBigInt3) {
+    let x = val;
+    // Used just to import pack in scope
+    %{
+        from starkware.cairo.common.cairo_secp.secp_utils import SECP_P, pack
+
+        value = pack(ids.x, PRIME) % SECP_P
+    %}
+    nondet_bigint3();
+
+    let q = [ap];
+    %{
+        from starkware.cairo.common.cairo_secp.secp_utils import SECP_P
+        q, r = divmod(pack(ids.val, PRIME), SECP_P)
+        assert r == 0, f"verify_zero: Invalid input {ids.val.d0, ids.val.d1, ids.val.d2}."
+        ids.q = q % PRIME
+    %}
+    let q_biased = [ap + 1];
+    q_biased = q + 2 ** 127, ap++;
+    [range_check_ptr] = q_biased, ap++;
+
+    tempvar r1 = (val.d0 + q * SECP_REM) / BASE;
+    assert [range_check_ptr + 1] = r1 + 2 ** 127;
+    // This implies r1 * BASE = val.d0 + q * SECP_REM (as integers).
+
+    tempvar r2 = (val.d1 + r1) / BASE;
+    assert [range_check_ptr + 2] = r2 + 2 ** 127;
+    // This implies r2 * BASE = val.d1 + r1 (as integers).
+    // Therefore, r2 * BASE**2 = val.d1 * BASE + r1 * BASE.
+
+    assert val.d2 = q * (BASE / 4) - r2;
+    // This implies q * BASE / 4 = val.d2 + r2 (as integers).
+    // Therefore,
+    //   q * BASE**3 / 4 = val.d2 * BASE**2 + r2 * BASE ** 2 =
+    //   val.d2 * BASE**2 + val.d1 * BASE + r1 * BASE =
+    //   val.d2 * BASE**2 + val.d1 * BASE + val.d0 + q * SECP_REM =
+    //   val + q * SECP_REM.
+    // Hence, val = q * (BASE**3 / 4 - SECP_REM) = q * (2**256 - SECP_REM).
+
+    let range_check_ptr = range_check_ptr + 3;
+    return ();
+}
+
+func test_verify_zero{range_check_ptr: felt}() {
+    let val = UnreducedBigInt3(0, 0, 0);
+
+    verify_zero(val);
+
+    return ();
+}
+
+func main{range_check_ptr: felt}() {
+    test_verify_zero();
+
+    return ();
+}

src/hint_processor/builtin_hint_processor/builtin_hint_processor_definition.rs

@@ -244,7 +244,9 @@ impl HintProcessor for BuiltinHintProcessor {
             hint_code::BLAKE2S_COMPUTE => {
                 compute_blake2s(vm, &hint_data.ids_data, &hint_data.ap_tracking)
             }
-            hint_code::VERIFY_ZERO => verify_zero(vm, &hint_data.ids_data, &hint_data.ap_tracking),
+            hint_code::VERIFY_ZERO_V1 | hint_code::VERIFY_ZERO_V2 => {
+                verify_zero(vm, &hint_data.ids_data, &hint_data.ap_tracking)
+            }
             hint_code::NONDET_BIGINT3 => {
                 nondet_bigint3(vm, exec_scopes, &hint_data.ids_data, &hint_data.ap_tracking)
             }
@@ -353,12 +355,36 @@ impl HintProcessor for BuiltinHintProcessor {
             hint_code::EC_NEGATE => {
                 ec_negate(vm, exec_scopes, &hint_data.ids_data, &hint_data.ap_tracking)
             }
-            hint_code::EC_DOUBLE_SCOPE => {
-                compute_doubling_slope(vm, exec_scopes, &hint_data.ids_data, &hint_data.ap_tracking)
-            }
-            hint_code::COMPUTE_SLOPE => {
-                compute_slope(vm, exec_scopes, &hint_data.ids_data, &hint_data.ap_tracking)
-            }
+            hint_code::EC_DOUBLE_SCOPE => compute_doubling_slope(
+                vm,
+                exec_scopes,
+                &hint_data.ids_data,
+                &hint_data.ap_tracking,
+                "point",
+            ),
+            hint_code::EC_DOUBLE_SCOPE_WHITELIST => compute_doubling_slope(
+                vm,
+                exec_scopes,
+                &hint_data.ids_data,
+                &hint_data.ap_tracking,
+                "pt",
+            ),
+            hint_code::COMPUTE_SLOPE => compute_slope(
+                vm,
+                exec_scopes,
+                &hint_data.ids_data,
+                &hint_data.ap_tracking,
+                "point0",
+                "point1",
+            ),
+            hint_code::COMPUTE_SLOPE_WHITELIST => compute_slope(
+                vm,
+                exec_scopes,
+                &hint_data.ids_data,
+                &hint_data.ap_tracking,
+                "pt0",
+                "pt1",
+            ),
             hint_code::EC_DOUBLE_ASSIGN_NEW_X => {
                 ec_double_assign_new_x(vm, exec_scopes, &hint_data.ids_data, &hint_data.ap_tracking)
             }

src/hint_processor/builtin_hint_processor/hint_code.rs

@@ -372,12 +372,17 @@ pub(crate) const NONDET_BIGINT3: &str = r#"from starkware.cairo.common.cairo_sec
 
 segments.write_arg(ids.res.address_, split(value))"#;
 
-pub(crate) const VERIFY_ZERO: &str = r#"from starkware.cairo.common.cairo_secp.secp_utils import SECP_P, pack
+pub(crate) const VERIFY_ZERO_V1: &str = r#"from starkware.cairo.common.cairo_secp.secp_utils import SECP_P, pack
 
 q, r = divmod(pack(ids.val, PRIME), SECP_P)
 assert r == 0, f"verify_zero: Invalid input {ids.val.d0, ids.val.d1, ids.val.d2}."
 ids.q = q % PRIME"#;
 
+pub(crate) const VERIFY_ZERO_V2: &str = r#"from starkware.cairo.common.cairo_secp.secp_utils import SECP_P
+q, r = divmod(pack(ids.val, PRIME), SECP_P)
+assert r == 0, f"verify_zero: Invalid input {ids.val.d0, ids.val.d1, ids.val.d2}."
+ids.q = q % PRIME"#;
+
 pub(crate) const REDUCE: &str = r#"from starkware.cairo.common.cairo_secp.secp_utils import SECP_P, pack
 
 value = pack(ids.x, PRIME) % SECP_P"#;
@@ -455,6 +460,14 @@ x = pack(ids.point.x, PRIME)
 y = pack(ids.point.y, PRIME)
 value = slope = ec_double_slope(point=(x, y), alpha=0, p=SECP_P)"#;
 
+pub(crate) const EC_DOUBLE_SCOPE_WHITELIST: &str = r#"from starkware.cairo.common.cairo_secp.secp_utils import SECP_P, pack
+from starkware.python.math_utils import div_mod
+
+# Compute the slope.
+x = pack(ids.pt.x, PRIME)
+y = pack(ids.pt.y, PRIME)
+value = slope = div_mod(3 * x ** 2, 2 * y, SECP_P)"#;
+
 pub(crate) const COMPUTE_SLOPE: &str = r#"from starkware.cairo.common.cairo_secp.secp_utils import SECP_P, pack
 from starkware.python.math_utils import line_slope
 
@@ -465,6 +478,16 @@ x1 = pack(ids.point1.x, PRIME)
 y1 = pack(ids.point1.y, PRIME)
 value = slope = line_slope(point1=(x0, y0), point2=(x1, y1), p=SECP_P)"#;
 
+pub(crate) const COMPUTE_SLOPE_WHITELIST: &str = r#"from starkware.cairo.common.cairo_secp.secp_utils import SECP_P, pack
+from starkware.python.math_utils import div_mod
+
+# Compute the slope.
+x0 = pack(ids.pt0.x, PRIME)
+y0 = pack(ids.pt0.y, PRIME)
+x1 = pack(ids.pt1.x, PRIME)
+y1 = pack(ids.pt1.y, PRIME)
+value = slope = div_mod(y0 - y1, x0 - x1, SECP_P)"#;
+
 pub(crate) const EC_DOUBLE_ASSIGN_NEW_X: &str = r#"from starkware.cairo.common.cairo_secp.secp_utils import SECP_P, pack
 
 slope = pack(ids.slope, PRIME)