1 files changed, 113 insertions, 0 deletions
diff --git a/src/common/crypto_ed25519.h b/src/common/crypto_ed25519.h
new file mode 100644
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+++ b/src/common/crypto_ed25519.h
@@ -0,0 +1,113 @@
+/* Copyright (c) 2012-2015, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#ifndef TOR_CRYPTO_ED25519_H
+#define TOR_CRYPTO_ED25519_H
+
+#include "testsupport.h"
+#include "torint.h"
+
+#define ED25519_PUBKEY_LEN 32
+#define ED25519_SECKEY_LEN 64
+#define ED25519_SECKEY_SEED_LEN 32
+#define ED25519_SIG_LEN 64
+
+/** An Ed25519 signature. */
+typedef struct {
+  uint8_t sig[ED25519_SIG_LEN];
+} ed25519_signature_t;
+
+/** An Ed25519 public key */
+typedef struct {
+  uint8_t pubkey[ED25519_PUBKEY_LEN];
+} ed25519_public_key_t;
+
+/** An Ed25519 secret key */
+typedef struct {
+  /** Note that we store secret keys in an expanded format that doesn't match
+   * the format from standard ed25519.  Ed25519 stores a 32-byte value k and
+   * expands it into a 64-byte H(k), using the first 32 bytes for a multiplier
+   * of the base point, and second 32 bytes as an input to a hash function
+   * for deriving r.  But because we implement key blinding, we need to store
+   * keys in the 64-byte expanded form. */
+  uint8_t seckey[ED25519_SECKEY_LEN];
+} ed25519_secret_key_t;
+
+/** An Ed25519 keypair. */
+typedef struct {
+  ed25519_public_key_t pubkey;
+  ed25519_secret_key_t seckey;
+} ed25519_keypair_t;
+
+int ed25519_secret_key_generate(ed25519_secret_key_t *seckey_out,
+                            int extra_strong);
+int ed25519_secret_key_from_seed(ed25519_secret_key_t *seckey_out,
+                                 const uint8_t *seed);
+
+int ed25519_public_key_generate(ed25519_public_key_t *pubkey_out,
+                            const ed25519_secret_key_t *seckey);
+int ed25519_keypair_generate(ed25519_keypair_t *keypair_out, int extra_strong);
+int ed25519_sign(ed25519_signature_t *signature_out,
+                 const uint8_t *msg, size_t len,
+                 const ed25519_keypair_t *key);
+int ed25519_checksig(const ed25519_signature_t *signature,
+                     const uint8_t *msg, size_t len,
+                     const ed25519_public_key_t *pubkey);
+
+/**
+ * A collection of information necessary to check an Ed25519 signature. Used
+ * for batch verification.
+ */
+typedef struct {
+  /** The public key that supposedly generated the signature. */
+  ed25519_public_key_t *pubkey;
+  /** The signature to check. */
+  ed25519_signature_t signature;
+  /** The message that the signature is supposed to have been applied to. */
+  const uint8_t *msg;
+  /** The length of the message. */
+  size_t len;
+} ed25519_checkable_t;
+
+int ed25519_checksig_batch(int *okay_out,
+                           const ed25519_checkable_t *checkable,
+                           int n_checkable);
+
+int ed25519_keypair_from_curve25519_keypair(ed25519_keypair_t *out,
+                                            int *signbit_out,
+                                            const curve25519_keypair_t *inp);
+
+int ed25519_public_key_from_curve25519_public_key(ed25519_public_key_t *pubkey,
+                                     const curve25519_public_key_t *pubkey_in,
+                                     int signbit);
+int ed25519_keypair_blind(ed25519_keypair_t *out,
+                          const ed25519_keypair_t *inp,
+                          const uint8_t *param);
+int ed25519_public_blind(ed25519_public_key_t *out,
+                         const ed25519_public_key_t *inp,
+                         const uint8_t *param);
+
+#define ED25519_BASE64_LEN 43
+
+int ed25519_public_from_base64(ed25519_public_key_t *pkey,
+                               const char *input);
+int ed25519_public_to_base64(char *output,
+                             const ed25519_public_key_t *pkey);
+
+/* XXXX read encrypted, write encrypted. */
+
+int ed25519_seckey_write_to_file(const ed25519_secret_key_t *seckey,
+                                 const char *filename,
+                                 const char *tag);
+int ed25519_seckey_read_from_file(ed25519_secret_key_t *seckey_out,
+                                  char **tag_out,
+                                  const char *filename);
+int ed25519_pubkey_write_to_file(const ed25519_public_key_t *pubkey,
+                                 const char *filename,
+                                 const char *tag);
+int ed25519_pubkey_read_from_file(ed25519_public_key_t *pubkey_out,
+                                  char **tag_out,
+                                  const char *filename);
+
+#endif
+