From: Loup Vaillant <loup@loup-vaillant.fr>
Date: Thu, 29 Dec 2022 23:10:06 +0000 (+0100)
Subject: Argon2: fix buffer overflow
X-Git-Url: https://git.codecow.com/?a=commitdiff_plain;h=b8b5edda7c7f9987dbf22eb08c5a837021d7ee14;p=Monocypher.git

Argon2: fix buffer overflow
---

diff --git a/src/monocypher.c b/src/monocypher.c
index cac46fb..11b817e 100644
--- a/src/monocypher.c
+++ b/src/monocypher.c
@@ -831,7 +831,7 @@ void crypto_argon2(u8 *hash, void *work_area, const u8 *password,
 					u32 window_size  = nb_segments * segment_size + block - 1;
 
 					// Generate offset from pseudo-random seed
-					u64 seed  = index_block.a[block];
+					u64 seed  = index_block.a[block % 128];
 					u64 j1    = seed & 0xffffffff; // block selector
 					u64 j2    = seed >> 32;        // lane selector
 					u64 x     = (j1 * j1)         >> 32;
@@ -862,6 +862,7 @@ void crypto_argon2(u8 *hash, void *work_area, const u8 *password,
 			}
 		}
 	}
+
 	// Wipe temporary block
 	volatile u64* p = tmp.a;
 	ZERO(p, 128);
diff --git a/tests/gen/argon2i.c b/tests/gen/argon2i.c
index 3bbee5f..fca623b 100644
--- a/tests/gen/argon2i.c
+++ b/tests/gen/argon2i.c
@@ -83,7 +83,7 @@ static void test(size_t nb_blocks, size_t hash_size, size_t nb_iterations)
 int main(void)
 {
 	SODIUM_INIT;
-	FOR (nb_blocks    , 508, 516) { test(nb_blocks, 32       , 3            ); }
+	FOR (nb_blocks    , 508, 517) { test(nb_blocks, 32       , 3            ); }
 	FOR (hash_size    ,  63,  65) { test(8        , hash_size, 3            ); }
 	FOR (nb_iterations,   3,   6) { test(8        , 32       , nb_iterations); }
 	return 0;