libsodium support for asymmetric cryptofeature/libsodium-integration

Signed-off-by: Toni Uhlig <matzeton@googlemail.com>

3 files changed, 42 insertions, 1 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 5786a01..2db50bc 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -2,7 +2,7 @@ bin_PROGRAMS = ptunnel-ng
 man8_MANS = ptunnel-ng.8
 
 ptunnel_ng_CFLAGS = -Wall -Wextra
-ptunnel_ng_LDADD =
+ptunnel_ng_LDADD = -lsodium
 CLEANFILES =
 EXTTRA_DIST =
 
@@ -39,6 +39,7 @@ ptunnel_ng_CFLAGS += -fsanitize=address -fsanitize=leak -fsanitize=undefined
 endif
 
 ptunnel_ng_SOURCES = \
+	crypto-sodium.c \
 	md5.c \
 	challenge.c \
 	options.c \
diff --git a/src/crypto-sodium.c b/src/crypto-sodium.c
new file mode 100644
index 0000000..c023ef4
--- /dev/null
+++ b/src/crypto-sodium.c
@@ -0,0 +1 @@
+#include "crypto-sodium.h"
diff --git a/src/crypto-sodium.h b/src/crypto-sodium.h
new file mode 100644
index 0000000..5994056
--- /dev/null
+++ b/src/crypto-sodium.h
@@ -0,0 +1,39 @@
+#ifndef CRYPTO_SODIUM_H
+#define CRYPTO_SODIUM_H 1
+
+#include <sodium.h>
+#include <stdint.h>
+
+struct longterm_keypair {
+    uint8_t publickey[crypto_kx_PUBLICKEYBYTES];
+    uint8_t secretkey[crypto_kx_SECRETKEYBYTES];
+};
+
+struct longterm_keypair * generate_keypair_from_secretkey_hexstr_sodium(char const * const secretkey_hexstr,
+                                                                        size_t secretkey_hexstr_len)
+{
+    struct longterm_keypair * keypair = (struct longterm_keypair *)malloc(sizeof(*keypair));
+
+    if (keypair == NULL) {
+        return NULL;
+    }
+
+    if (sodium_hex2bin(keypair->secretkey, sizeof(keypair->secretkey),
+                       secretkey_hexstr, secretkey_hexstr_len, NULL, NULL, NULL) != 0)
+    {
+        goto error;
+    }
+
+    if (crypto_scalarmult_base(keypair->publickey, keypair->secretkey) != 0) {
+        goto error;
+    }
+
+    sodium_mlock(keypair, sizeof(*keypair));
+
+    return keypair;
+error:
+    free(keypair);
+    return NULL;
+}
+
+#endif