Remove elliptic curve stubs from gcrypt/, add PRF implementation.

diff --git a/src/gcrypt/ecdh.c b/src/gcrypt/ecdh.c
deleted file mode 100644 (file)
index 4e30733..0000000
--- a/src/gcrypt/ecdh.c
+++ /dev/null
@@ -1,37 +0,0 @@
-/*
-    ecdh.c -- Diffie-Hellman key exchange handling
-    Copyright (C) 2011-2013 Guus Sliepen <guus@tinc-vpn.org>
-
-    This program is free software; you can redistribute it and/or modify
-    it under the terms of the GNU General Public License as published by
-    the Free Software Foundation; either version 2 of the License, or
-    (at your option) any later version.
-
-    This program is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
-
-    You should have received a copy of the GNU General Public License along
-    with this program; if not, write to the Free Software Foundation, Inc.,
-    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
-*/
-
-#include "../system.h"
-
-#include "../ecdh.h"
-#include "../logger.h"
-#include "../utils.h"
-#include "../xalloc.h"
-
-ecdh_t *ecdh_generate_public(void *pubkey) {
-       logger(DEBUG_ALWAYS, LOG_ERR, "EC support using libgcrypt not implemented");
-       return NULL;
-}
-
-bool ecdh_compute_shared(ecdh_t *ecdh, const void *pubkey, void *shared) {
-       return false
-}
-
-void ecdh_free(ecdh_t *ecdh) {
-}

diff --git a/src/gcrypt/ecdsa.c b/src/gcrypt/ecdsa.c
deleted file mode 100644 (file)
index ee19aec..0000000
--- a/src/gcrypt/ecdsa.c
+++ /dev/null
@@ -1,67 +0,0 @@
-/*
-    ecdsa.c -- ECDSA key handling
-    Copyright (C) 2011-2013 Guus Sliepen <guus@tinc-vpn.org>
-
-    This program is free software; you can redistribute it and/or modify
-    it under the terms of the GNU General Public License as published by
-    the Free Software Foundation; either version 2 of the License, or
-    (at your option) any later version.
-
-    This program is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
-
-    You should have received a copy of the GNU General Public License along
-    with this program; if not, write to the Free Software Foundation, Inc.,
-    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
-*/
-
-#include "../system.h"
-
-#include "../logger.h"
-#include "../ecdsa.h"
-#include "../utils.h"
-#include "../xalloc.h"
-
-// Get and set ECDSA keys
-//
-ecdsa_t *ecdsa_set_base64_public_key(const char *p) {
-       logger(DEBUG_ALWAYS, LOG_ERR, "EC support using libgcrypt not implemented");
-       return NULL;
-}
-
-char *ecdsa_get_base64_public_key(ecdsa_t *ecdsa) {
-       return NULL;
-}
-
-// Read PEM ECDSA keys
-
-ecdsa_t *ecdsa_read_pem_public_key(FILE *fp) {
-       logger(DEBUG_ALWAYS, LOG_ERR, "EC support using libgcrypt not implemented");
-       return NULL;
-}
-
-ecdsa_t *ecdsa_read_pem_private_key(FILE *fp) {
-       logger(DEBUG_ALWAYS, LOG_ERR, "EC support using libgcrypt not implemented");
-       return NULL;
-}
-
-size_t ecdsa_size(ecdsa_t *ecdsa) {
-       return 0;
-}
-
-bool ecdsa_sign(ecdsa_t *ecdsa, const void *in, size_t len, void *sig) {
-       return false;
-}
-
-bool ecdsa_verify(ecdsa_t *ecdsa, const void *in, size_t len, const void *sig) {
-       return false;
-}
-
-bool ecdsa_active(ecdsa_t *ecdsa) {
-       return false;
-}
-
-void ecdsa_free(ecdsa_t *ecdsa) {
-}

diff --git a/src/gcrypt/ecdsagen.c b/src/gcrypt/ecdsagen.c
deleted file mode 100644 (file)
index 2d4912d..0000000
--- a/src/gcrypt/ecdsagen.c
+++ /dev/null
@@ -1,41 +0,0 @@
-/*
-    ecdsagen.c -- ECDSA key generation and export
-    Copyright (C) 2011-2013 Guus Sliepen <guus@tinc-vpn.org>
-
-    This program is free software; you can redistribute it and/or modify
-    it under the terms of the GNU General Public License as published by
-    the Free Software Foundation; either version 2 of the License, or
-    (at your option) any later version.
-
-    This program is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
-
-    You should have received a copy of the GNU General Public License along
-    with this program; if not, write to the Free Software Foundation, Inc.,
-    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
-*/
-
-#include "../system.h"
-
-#include "../ecdsagen.h"
-#include "../utils.h"
-#include "../xalloc.h"
-
-// Generate ECDSA key
-
-ecdsa_t *ecdsa_generate(void) {
-       logger(DEBUG_ALWAYS, LOG_ERR, "EC support using libgcrypt not implemented");
-       return NULL;
-}
-
-// Write PEM ECDSA keys
-
-bool ecdsa_write_pem_public_key(ecdsa_t *ecdsa, FILE *fp) {
-       return false;
-}
-
-bool ecdsa_write_pem_private_key(ecdsa_t *ecdsa, FILE *fp) {
-       return false;
-}

diff --git a/src/gcrypt/prf.c b/src/gcrypt/prf.c
index f9a2112..55c9923 100644 (file)
--- a/src/gcrypt/prf.c
+++ b/src/gcrypt/prf.c
@@ -19,11 +19,88 @@
 
 #include "../system.h"
 
-#include "digest.h"
-#include "../digest.h"
 #include "../prf.h"
+#include "../ed25519/sha512.h"
+
+static void memxor(char *buf, char c, size_t len) {
+       for(size_t i = 0; i < len; i++)
+               buf[i] ^= c;
+}
+
+static const size_t mdlen = 64;
+static const size_t blklen = 128;
+
+static bool hmac_sha512(const char *key, size_t keylen, const char *msg, size_t msglen, char *out) {
+       char tmp[blklen + mdlen];
+       sha512_context md;
+
+       if(keylen <= blklen) {
+               memcpy(tmp, key, keylen);
+               memset(tmp + keylen, 0, blklen - keylen);
+       } else {
+               if(sha512(key, keylen, tmp) != 0)
+                       return false;
+               memset(tmp + mdlen, 0, blklen - mdlen);
+       }
+
+       if(sha512_init(&md) != 0)
+               return false;
+
+       // ipad
+       memxor(tmp, 0x36, blklen);
+       if(sha512_update(&md, tmp, blklen) != 0)
+               return false;
+
+       // message
+       if(sha512_update(&md, msg, msglen) != 0)
+               return false;
+
+       if(sha512_final(&md, tmp + blklen) != 0)
+               return false;
+
+       // opad
+       memxor(tmp, 0x36 ^ 0x5c, blklen);
+       if(sha512(tmp, sizeof tmp, out) != 0)
+               return false;
+
+       return true;
+}
+
+
+/* Generate key material from a master secret and a seed, based on RFC 4346 section 5.
+   We use SHA512 instead of MD5 and SHA1.
+ */
 
 bool prf(const char *secret, size_t secretlen, char *seed, size_t seedlen, char *out, size_t outlen) {
-       logger(DEBUG_ALWAYS, LOG_ERR, "PRF support using libgcrypt not implemented");
-       return false;
+       /* Data is what the "inner" HMAC function processes.
+          It consists of the previous HMAC result plus the seed.
+        */
+
+       char data[mdlen + seedlen];
+       memset(data, 0, mdlen);
+       memcpy(data + mdlen, seed, seedlen);
+
+       char hash[mdlen];
+
+       while(outlen > 0) {
+               /* Inner HMAC */
+               if(!hmac_sha512(secret, secretlen, data, sizeof data, data))
+                       return false;
+
+               /* Outer HMAC */
+               if(outlen >= mdlen) {
+                       if(!hmac_sha512(secret, secretlen, data, sizeof data, out))
+                               return false;
+                       out += mdlen;
+                       outlen -= mdlen;
+               } else {
+                       if(!hmac_sha512(secret, secretlen, data, sizeof data, hash))
+                               return false;
+                       memcpy(out, hash, outlen);
+                       out += outlen;
+                       outlen = 0;
+               }
+       }
+
+       return true;
 }