Add basic routines for digital signatures

5 files changed, 169 insertions, 16 deletions

diff --git a/src/libcryptobox/cryptobox.c b/src/libcryptobox/cryptobox.c
index 5f0bb3b64..3d7c57c85 100644
--- a/src/libcryptobox/cryptobox.c
+++ b/src/libcryptobox/cryptobox.c
@@ -33,6 +33,7 @@
 #include "chacha20/chacha.h"
 #include "poly1305/poly1305.h"
 #include "curve25519/curve25519.h"
+#include "ed25519/ed25519.h"
 #include "blake2/blake2.h"
 #include "siphash/siphash.h"
 #include "ottery.h"
@@ -53,7 +54,7 @@
 #include <openssl/evp.h>
 #include <openssl/ec.h>
 #include <openssl/ecdh.h>
-
+#include <openssl/ecdsa.h>
 #define CRYPTOBOX_CURVE_NID NID_X9_62_prime256v1
 #endif
 
@@ -315,6 +316,7 @@ rspamd_cryptobox_init (void)
 	ctx->siphash_impl = siphash_load ();
 	ctx->curve25519_impl = curve25519_load ();
 	ctx->blake2_impl = blake2b_load ();
+	ctx->ed25519_impl = ed25519_load ();
 
 	return ctx;
 }
@@ -364,6 +366,45 @@ rspamd_cryptobox_keypair (rspamd_pk_t pk, rspamd_sk_t sk)
 }
 
 void
+rspamd_cryptobox_keypair_sig (rspamd_sig_pk_t pk, rspamd_sig_sk_t sk)
+{
+	if (G_LIKELY (!use_openssl)) {
+		ed25519_keypair (pk, sk);
+	}
+	else {
+#ifndef HAVE_USABLE_OPENSSL
+		g_assert (0);
+#else
+		EC_KEY *ec_sec;
+		const BIGNUM *bn_sec;
+		BIGNUM *bn_pub;
+		const EC_POINT *ec_pub;
+		gint len;
+
+		ec_sec = EC_KEY_new_by_curve_name (CRYPTOBOX_CURVE_NID);
+		g_assert (ec_sec != NULL);
+		g_assert (EC_KEY_generate_key (ec_sec) != 0);
+
+		bn_sec = EC_KEY_get0_private_key (ec_sec);
+		g_assert (bn_sec != NULL);
+		ec_pub = EC_KEY_get0_public_key (ec_sec);
+		g_assert (ec_pub != NULL);
+		bn_pub = EC_POINT_point2bn (EC_KEY_get0_group (ec_sec),
+				ec_pub, POINT_CONVERSION_UNCOMPRESSED, NULL, NULL);
+
+		len = BN_num_bytes (bn_sec);
+		g_assert (len <= (gint)sizeof (rspamd_sk_t));
+		BN_bn2bin (bn_sec, sk);
+		len = BN_num_bytes (bn_pub);
+		g_assert (len <= (gint)rspamd_cryptobox_pk_bytes ());
+		BN_bn2bin (bn_pub, pk);
+		BN_free (bn_pub);
+		EC_KEY_free (ec_sec);
+#endif
+	}
+}
+
+void
 rspamd_cryptobox_nm (rspamd_nm_t nm, const rspamd_pk_t pk, const rspamd_sk_t sk)
 {
 	if (G_LIKELY (!use_openssl)) {
@@ -415,6 +456,43 @@ rspamd_cryptobox_nm (rspamd_nm_t nm, const rspamd_pk_t pk, const rspamd_sk_t sk)
 	}
 }
 
+void
+rspamd_cryptobox_sign (guchar *sig, gsize *siglen_p,
+		const guchar *m, gsize mlen,
+		const rspamd_sk_t sk)
+{
+	if (G_LIKELY (!use_openssl)) {
+		ed25519_sign (sig, siglen_p, m, mlen, sk);
+	}
+	else {
+#ifndef HAVE_USABLE_OPENSSL
+		g_assert (0);
+#else
+#endif
+	}
+}
+
+bool
+rspamd_cryptobox_verify (const guchar *sig,
+		const guchar *m,
+		gsize mlen,
+		const rspamd_pk_t pk)
+{
+	bool ret = false;
+
+	if (G_LIKELY (!use_openssl)) {
+		ret = ed25519_verify (sig, m, mlen, pk);
+	}
+	else {
+#ifndef HAVE_USABLE_OPENSSL
+		g_assert (0);
+#else
+#endif
+	}
+
+	return ret;
+}
+
 static gsize
 rspamd_cryptobox_encrypt_ctx_len (void)
 {
@@ -1105,6 +1183,17 @@ rspamd_cryptobox_pk_bytes (void)
 }
 
 guint
+rspamd_cryptobox_pk_sig_bytes (void)
+{
+	if (G_UNLIKELY (!use_openssl)) {
+		return 32;
+	}
+	else {
+		return 65;
+	}
+}
+
+guint
 rspamd_cryptobox_nonce_bytes (void)
 {
 	if (G_UNLIKELY (!use_openssl)) {
@@ -1123,6 +1212,17 @@ rspamd_cryptobox_sk_bytes (void)
 }
 
 guint
+rspamd_cryptobox_sk_sig_bytes (void)
+{
+	if (G_UNLIKELY (!use_openssl)) {
+		return 32;
+	}
+	else {
+		return 64;
+	}
+}
+
+guint
 rspamd_cryptobox_nm_bytes (void)
 {
 	return 32;
diff --git a/src/libcryptobox/cryptobox.h b/src/libcryptobox/cryptobox.h
index 8673fa091..966fc677e 100644
--- a/src/libcryptobox/cryptobox.h
+++ b/src/libcryptobox/cryptobox.h
@@ -57,10 +57,14 @@ typedef guchar rspamd_mac_t[rspamd_cryptobox_MAX_MACBYTES];
 typedef guchar rspamd_nm_t[rspamd_cryptobox_MAX_NMBYTES];
 typedef guchar rspamd_nonce_t[rspamd_cryptobox_MAX_NONCEBYTES];
 typedef guchar rspamd_sipkey_t[rspamd_cryptobox_SIPKEYBYTES];
+typedef guchar rspamd_signature_t[rspamd_cryptobox_MAX_SIGBYTES];
+typedef guchar rspamd_sig_pk_t[rspamd_cryptobox_MAX_SIGPKBYTES];
+typedef guchar rspamd_sig_sk_t[rspamd_cryptobox_MAX_SIGSKBYTES];
 
 struct rspamd_cryptobox_library_ctx {
 	gchar *cpu_extensions;
 	const gchar *curve25519_impl;
+	const gchar *ed25519_impl;
 	const gchar *chacha20_impl;
 	const gchar *poly1305_impl;
 	const gchar *siphash_impl;
@@ -81,6 +85,13 @@ struct rspamd_cryptobox_library_ctx* rspamd_cryptobox_init (void);
 void rspamd_cryptobox_keypair (rspamd_pk_t pk, rspamd_sk_t sk);
 
 /**
+ * Generate new keypair for signing
+ * @param pk public key buffer
+ * @param sk secret key buffer
+ */
+void rspamd_cryptobox_keypair_sig (rspamd_sig_pk_t pk, rspamd_sig_sk_t sk);
+
+/**
  * Encrypt data inplace adding signature to sig afterwards
  * @param data input buffer
  * @param pk remote pubkey
@@ -166,6 +177,32 @@ gboolean rspamd_cryptobox_decrypt_nm_inplace (guchar *data, gsize len,
 void rspamd_cryptobox_nm (rspamd_nm_t nm, const rspamd_pk_t pk, const rspamd_sk_t sk);
 
 /**
+ * Create digital signature for the specified message and place result in `sig`
+ * @param sig signature target
+ * @param siglen_p pointer to signature length (might be NULL)
+ * @param m input message
+ * @param mlen input length
+ * @param sk secret key
+ */
+void rspamd_cryptobox_sign (guchar *sig, gsize *siglen_p,
+		const guchar *m, gsize mlen,
+		const rspamd_sk_t sk);
+
+/**
+ * Verifies digital signature for the specified message using the specified
+ * pubkey
+ * @param sig signature source
+ * @param m input message
+ * @param mlen message lenght
+ * @param pk public key for verification
+ * @return true if signature is valid, false otherwise
+ */
+bool rspamd_cryptobox_verify (const guchar *sig,
+		const guchar *m,
+		gsize mlen,
+		const rspamd_pk_t pk);
+
+/**
  * Securely clear the buffer specified
  * @param buf buffer to zero
  * @param buflen length of buffer
@@ -210,6 +247,11 @@ gboolean rspamd_cryptobox_openssl_mode (gboolean enable);
 guint rspamd_cryptobox_pk_bytes (void);
 
 /**
+ * Real size of rspamd cryptobox signing public key
+ */
+guint rspamd_cryptobox_pk_sig_bytes (void);
+
+/**
  * Real size of crypto nonce
  */
 guint rspamd_cryptobox_nonce_bytes (void);
@@ -220,6 +262,11 @@ guint rspamd_cryptobox_nonce_bytes (void);
 guint rspamd_cryptobox_sk_bytes (void);
 
 /**
+ * Real size of rspamd cryptobox signing secret key
+ */
+guint rspamd_cryptobox_sk_sig_bytes (void);
+
+/**
  * Real size of rspamd cryptobox shared key
  */
 guint rspamd_cryptobox_nm_bytes (void);
@@ -229,6 +276,11 @@ guint rspamd_cryptobox_nm_bytes (void);
  */
 guint rspamd_cryptobox_mac_bytes (void);
 
+/**
+ * Real size of rspamd cryptobox digital signature
+ */
+guint rspamd_cryptobox_signature_bytes (void);
+
 /* Hash IUF interface */
 typedef struct RSPAMD_ALIGNED(32) rspamd_cryptobox_hash_state_s  {
 	unsigned char opaque[256];
diff --git a/src/libcryptobox/ed25519/ed25519.c b/src/libcryptobox/ed25519/ed25519.c
index 776ac4e13..f4658aff5 100644
--- a/src/libcryptobox/ed25519/ed25519.c
+++ b/src/libcryptobox/ed25519/ed25519.c
@@ -34,23 +34,23 @@ typedef struct ed25519_impl_s {
 	const char *desc;
 
 	void (*keypair) (unsigned char *pk, unsigned char *sk);
-	void (*sign) (unsigned char *sig, unsigned long long *siglen_p,
-			const unsigned char *m, unsigned long long mlen,
+	void (*sign) (unsigned char *sig, size_t *siglen_p,
+			const unsigned char *m, size_t mlen,
 			const unsigned char *sk);
 	bool (*verify) (const unsigned char *sig,
 			const unsigned char *m,
-			unsigned long long mlen,
+			size_t mlen,
 			const unsigned char *pk);
 } ed25519_impl_t;
 
 #define ED25519_DECLARE(ext) \
     void ed_keypair_##ext(unsigned char *pk, unsigned char *sk); \
-    void ed_sign_##ext(unsigned char *sig, unsigned long long *siglen_p, \
-        const unsigned char *m, unsigned long long mlen, \
+    void ed_sign_##ext(unsigned char *sig, size_t *siglen_p, \
+        const unsigned char *m, size_t mlen, \
         const unsigned char *sk); \
     bool ed_verify_##ext(const unsigned char *sig, \
         const unsigned char *m, \
-        unsigned long long mlen, \
+		size_t mlen, \
         const unsigned char *pk)
 
 #define ED25519_IMPL(cpuflags, desc, ext) \
@@ -90,8 +90,8 @@ ed25519_keypair (unsigned char *pk, unsigned char *sk)
 }
 
 void
-ed25519_sign (unsigned char *sig, unsigned long long *siglen_p,
-		const unsigned char *m, unsigned long long mlen,
+ed25519_sign (unsigned char *sig, size_t *siglen_p,
+		const unsigned char *m, size_t mlen,
 		const unsigned char *sk)
 {
 	ed25519_opt->sign (sig, siglen_p, m, mlen, sk);
@@ -100,7 +100,7 @@ ed25519_sign (unsigned char *sig, unsigned long long *siglen_p,
 bool
 ed25519_verify (const unsigned char *sig,
 		const unsigned char *m,
-		unsigned long long mlen,
+		size_t mlen,
 		const unsigned char *pk)
 {
 	return ed25519_opt->verify (sig, m, mlen, pk);
diff --git a/src/libcryptobox/ed25519/ed25519.h b/src/libcryptobox/ed25519/ed25519.h
index 34814782b..7a6cd796f 100644
--- a/src/libcryptobox/ed25519/ed25519.h
+++ b/src/libcryptobox/ed25519/ed25519.h
@@ -27,15 +27,16 @@
 
 #include "config.h"
 #include <stdbool.h>
+#include <stddef.h>
 
 const char* ed25519_load (void);
 void ed25519_keypair (unsigned char *pk, unsigned char *sk);
-void ed25519_sign (unsigned char *sig, unsigned long long *siglen_p,
-		const unsigned char *m, unsigned long long mlen,
+void ed25519_sign (unsigned char *sig, size_t *siglen_p,
+		const unsigned char *m, size_t mlen,
 		const unsigned char *sk);
 bool ed25519_verify (const unsigned char *sig,
 		const unsigned char *m,
-		unsigned long long mlen,
+		size_t mlen,
 		const unsigned char *pk);
 
 #endif /* SRC_LIBCRYPTOBOX_ED25519_ED25519_H_ */
diff --git a/src/libcryptobox/ed25519/ref.c b/src/libcryptobox/ed25519/ref.c
index a1053c607..5ae5eb898 100644
--- a/src/libcryptobox/ed25519/ref.c
+++ b/src/libcryptobox/ed25519/ref.c
@@ -59,7 +59,7 @@ ed_keypair_ref (unsigned char *pk, unsigned char *sk)
 
 int
 ed_verify_ref(const unsigned char *sig, const unsigned char *m,
-		unsigned long long mlen, const unsigned char *pk)
+		size_t mlen, const unsigned char *pk)
 {
 	EVP_MD_CTX sha_ctx;
 	unsigned char h[64];
@@ -96,8 +96,8 @@ ed_verify_ref(const unsigned char *sig, const unsigned char *m,
 }
 
 void
-ed_sign_ref(unsigned char *sig, unsigned long long *siglen_p,
-		const unsigned char *m, unsigned long long mlen,
+ed_sign_ref(unsigned char *sig, size_t *siglen_p,
+		const unsigned char *m, size_t mlen,
 		const unsigned char *sk)
 {
 	EVP_MD_CTX sha_ctx;