From 337fba6c23e1a45e6438cc89cec7908a808d677f Mon Sep 17 00:00:00 2001
From: Frank Denis <github@pureftpd.org>
Date: Thu, 5 Jan 2023 14:06:26 +0100
Subject: [PATCH] 2023

---
 LICENSE                                       |  2 +-
 .../crypto_kdf/hkdf/kdf_hkdf_sha256.c         | 39 ++++++++++++++++---
 .../include/sodium/crypto_kdf_hkdf_sha256.h   | 30 +++++++++++++-
 3 files changed, 62 insertions(+), 9 deletions(-)

diff --git a/LICENSE b/LICENSE
index 324bde66..17397208 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,7 +1,7 @@
 /*
  * ISC License
  *
- * Copyright (c) 2013-2022
+ * Copyright (c) 2013-2023
  * Frank Denis <j at pureftpd dot org>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
diff --git a/src/libsodium/crypto_kdf/hkdf/kdf_hkdf_sha256.c b/src/libsodium/crypto_kdf/hkdf/kdf_hkdf_sha256.c
index c8238640..8eb7c878 100644
--- a/src/libsodium/crypto_kdf/hkdf/kdf_hkdf_sha256.c
+++ b/src/libsodium/crypto_kdf/hkdf/kdf_hkdf_sha256.c
@@ -7,20 +7,42 @@
 #include "randombytes.h"
 #include "utils.h"
 
+int
+crypto_kdf_hkdf_sha256_extract_init(crypto_kdf_hkdf_sha256_state *state,
+                                    const unsigned char *salt, size_t salt_len)
+{
+    return crypto_auth_hmacsha256_init(&state->st, salt, salt_len);
+}
+
+int
+crypto_kdf_hkdf_sha256_extract_update(crypto_kdf_hkdf_sha256_state *state,
+                                      const unsigned char *ikm, size_t ikm_len)
+{
+    return crypto_auth_hmacsha256_update(&state->st, ikm, ikm_len);
+}
+
+int
+crypto_kdf_hkdf_sha256_extract_final(crypto_kdf_hkdf_sha256_state *state,
+                                     unsigned char prk[crypto_kdf_hkdf_sha256_KEYBYTES])
+{
+    crypto_auth_hmacsha256_final(&state->st, prk);
+    sodium_memzero(state, sizeof state);
+
+    return 0;
+}
+
 int
 crypto_kdf_hkdf_sha256_extract(
     unsigned char prk[crypto_kdf_hkdf_sha256_KEYBYTES],
     const unsigned char *salt, size_t salt_len, const unsigned char *ikm,
     size_t ikm_len)
 {
-    crypto_auth_hmacsha256_state st;
+    crypto_kdf_hkdf_sha256_state state;
 
-    crypto_auth_hmacsha256_init(&st, salt, salt_len);
-    crypto_auth_hmacsha256_update(&st, ikm, ikm_len);
-    crypto_auth_hmacsha256_final(&st, prk);
-    sodium_memzero(&st, sizeof st);
+    crypto_kdf_hkdf_sha256_extract_init(&state, salt, salt_len);
+    crypto_kdf_hkdf_sha256_extract_update(&state, ikm, ikm_len);
 
-    return 0;
+    return crypto_kdf_hkdf_sha256_extract_final(&state, prk);
 }
 
 void
@@ -94,3 +116,8 @@ crypto_kdf_hkdf_sha256_bytes_max(void)
 {
     return crypto_kdf_hkdf_sha256_BYTES_MAX;
 }
+
+size_t crypto_kdf_hkdf_sha256_statebytes(void)
+{
+    return sizeof(crypto_kdf_hkdf_sha256_state);
+}
diff --git a/src/libsodium/include/sodium/crypto_kdf_hkdf_sha256.h b/src/libsodium/include/sodium/crypto_kdf_hkdf_sha256.h
index 899a6316..e7e7f4db 100644
--- a/src/libsodium/include/sodium/crypto_kdf_hkdf_sha256.h
+++ b/src/libsodium/include/sodium/crypto_kdf_hkdf_sha256.h
@@ -31,7 +31,8 @@ size_t crypto_kdf_hkdf_sha256_bytes_max(void);
 SODIUM_EXPORT
 int crypto_kdf_hkdf_sha256_extract(unsigned char prk[crypto_kdf_hkdf_sha256_KEYBYTES],
                                    const unsigned char *salt, size_t salt_len,
-                                   const unsigned char *ikm, size_t ikm_len);
+                                   const unsigned char *ikm, size_t ikm_len)
+            __attribute__ ((nonnull(4)));
 
 SODIUM_EXPORT
 void crypto_kdf_hkdf_sha256_keygen(unsigned char prk[crypto_kdf_hkdf_sha256_KEYBYTES]);
@@ -39,7 +40,32 @@ void crypto_kdf_hkdf_sha256_keygen(unsigned char prk[crypto_kdf_hkdf_sha256_KEYB
 SODIUM_EXPORT
 int crypto_kdf_hkdf_sha256_expand(unsigned char *out, size_t out_len,
                                   const char *ctx, size_t ctx_len,
-                                  const unsigned char prk[crypto_kdf_hkdf_sha256_KEYBYTES]);
+                                  const unsigned char prk[crypto_kdf_hkdf_sha256_KEYBYTES])
+            __attribute__ ((nonnull(1)));
+
+/* ------------------------------------------------------------------------- */
+
+typedef struct crypto_kdf_hkdf_sha256_state {
+    crypto_auth_hmacsha256_state st;
+} crypto_kdf_hkdf_sha256_state;
+
+SODIUM_EXPORT
+size_t crypto_kdf_hkdf_sha256_statebytes(void);
+
+SODIUM_EXPORT
+int crypto_kdf_hkdf_sha256_extract_init(crypto_kdf_hkdf_sha256_state *state,
+                                        const unsigned char *salt, size_t salt_len)
+            __attribute__ ((nonnull(1)));
+
+SODIUM_EXPORT
+int crypto_kdf_hkdf_sha256_extract_update(crypto_kdf_hkdf_sha256_state *state,
+                                          const unsigned char *ikm, size_t ikm_len)
+            __attribute__ ((nonnull));
+
+SODIUM_EXPORT
+int crypto_kdf_hkdf_sha256_extract_final(crypto_kdf_hkdf_sha256_state *state,
+                                         unsigned char prk[crypto_kdf_hkdf_sha256_KEYBYTES])
+            __attribute__ ((nonnull));
 
 #ifdef __cplusplus
 }