1 files changed, 68 insertions, 0 deletions
diff --git a/libs/libsodium/src/crypto_box/crypto_box_seal.c b/libs/libsodium/src/crypto_box/crypto_box_seal.c
new file mode 100644
index 0000000000..7181334578
--- /dev/null
+++ b/libs/libsodium/src/crypto_box/crypto_box_seal.c
@@ -0,0 +1,68 @@
+
+#include <string.h>
+
+#include "crypto_box.h"
+#include "crypto_generichash.h"
+#include "private/common.h"
+#include "utils.h"
+
+static int
+_crypto_box_seal_nonce(unsigned char *nonce,
+                       const unsigned char *pk1, const unsigned char *pk2)
+{
+    crypto_generichash_state st;
+
+    crypto_generichash_init(&st, NULL, 0U, crypto_box_NONCEBYTES);
+    crypto_generichash_update(&st, pk1, crypto_box_PUBLICKEYBYTES);
+    crypto_generichash_update(&st, pk2, crypto_box_PUBLICKEYBYTES);
+    crypto_generichash_final(&st, nonce, crypto_box_NONCEBYTES);
+
+    return 0;
+}
+
+int
+crypto_box_seal(unsigned char *c, const unsigned char *m,
+                unsigned long long mlen, const unsigned char *pk)
+{
+    unsigned char nonce[crypto_box_NONCEBYTES];
+    unsigned char epk[crypto_box_PUBLICKEYBYTES];
+    unsigned char esk[crypto_box_SECRETKEYBYTES];
+    int           ret;
+
+    if (crypto_box_keypair(epk, esk) != 0) {
+        return -1; /* LCOV_EXCL_LINE */
+    }
+    memcpy(c, epk, crypto_box_PUBLICKEYBYTES);
+    _crypto_box_seal_nonce(nonce, epk, pk);
+    ret = crypto_box_easy(c + crypto_box_PUBLICKEYBYTES, m, mlen,
+                          nonce, pk, esk);
+    sodium_memzero(esk, sizeof esk);
+    sodium_memzero(epk, sizeof epk);
+    sodium_memzero(nonce, sizeof nonce);
+
+    return ret;
+}
+
+int
+crypto_box_seal_open(unsigned char *m, const unsigned char *c,
+                     unsigned long long clen,
+                     const unsigned char *pk, const unsigned char *sk)
+{
+    unsigned char nonce[crypto_box_NONCEBYTES];
+
+    if (clen < crypto_box_SEALBYTES) {
+        return -1;
+    }
+    _crypto_box_seal_nonce(nonce, c, pk);
+
+    COMPILER_ASSERT(crypto_box_PUBLICKEYBYTES < crypto_box_SEALBYTES);
+    return crypto_box_open_easy(m, c + crypto_box_PUBLICKEYBYTES,
+                                clen - crypto_box_PUBLICKEYBYTES,
+                                nonce, c, sk);
+}
+
+size_t
+crypto_box_sealbytes(void)
+{
+    return crypto_box_SEALBYTES;
+}