1 files changed, 409 insertions, 0 deletions
diff --git a/src/lib-dcrypt/dcrypt.h b/src/lib-dcrypt/dcrypt.h
new file mode 100644
index 0000000..0e8a9aa
--- /dev/null
+++ b/src/lib-dcrypt/dcrypt.h
@@ -0,0 +1,409 @@
+#ifndef DCRYPT_H
+#define DCRYPT_H 1
+#include "array.h"
+
+struct dcrypt_context_symmetric;
+struct dcrypt_context_hmac;
+struct dcrypt_public_key;
+struct dcrypt_private_key;
+
+struct dcrypt_keypair {
+	struct dcrypt_public_key *pub;
+	struct dcrypt_private_key *priv;
+};
+
+enum dcrypt_sym_mode {
+	DCRYPT_MODE_ENCRYPT,
+	DCRYPT_MODE_DECRYPT
+};
+
+enum dcrypt_key_type {
+	DCRYPT_KEY_RSA = 0x1,
+	DCRYPT_KEY_EC  = 0x2
+};
+
+/**
+ * dovecot key format:
+ * version version-specific data
+ * v1: version tab nid tab raw ec private key (in hex)
+ * v2: version colon algorithm oid colon private-or-public-key-only (in hex)
+ */
+enum dcrypt_key_format {
+	DCRYPT_FORMAT_PEM,
+	DCRYPT_FORMAT_DOVECOT,
+	DCRYPT_FORMAT_JWK, /* JSON Web Key (JWK) [RFC7517] */
+};
+
+enum dcrypt_key_encryption_type {
+	DCRYPT_KEY_ENCRYPTION_TYPE_NONE,
+	DCRYPT_KEY_ENCRYPTION_TYPE_KEY,
+	DCRYPT_KEY_ENCRYPTION_TYPE_PASSWORD
+};
+
+enum dcrypt_key_version {
+	DCRYPT_KEY_VERSION_1,
+	DCRYPT_KEY_VERSION_2,
+	DCRYPT_KEY_VERSION_NA /* not applicable, PEM key */
+};
+
+enum dcrypt_key_kind {
+	DCRYPT_KEY_KIND_PUBLIC,
+	DCRYPT_KEY_KIND_PRIVATE
+};
+
+enum dcrypt_key_usage {
+	DCRYPT_KEY_USAGE_NONE,
+	DCRYPT_KEY_USAGE_ENCRYPT,
+	DCRYPT_KEY_USAGE_SIGN,
+};
+
+enum dcrypt_signature_format {
+	DCRYPT_SIGNATURE_FORMAT_DSS,
+	DCRYPT_SIGNATURE_FORMAT_X962,
+};
+
+/* this parameter makes sense with RSA only
+   default for RSA means either PSS (sign/verify)
+   or OAEP (encrypt/decrypt).
+   for ECDSA default can be used.
+*/
+enum dcrypt_padding {
+	DCRYPT_PADDING_DEFAULT,
+	DCRYPT_PADDING_RSA_PKCS1_PSS,
+	DCRYPT_PADDING_RSA_PKCS1_OAEP,
+	DCRYPT_PADDING_RSA_PKCS1, /* for compatibility use only */
+	DCRYPT_PADDING_RSA_NO,
+};
+
+struct dcrypt_settings {
+	/* OpenSSL engine to use */
+	const char *crypto_device;
+	/* Look for backends in this directory */
+	const char *module_dir;
+};
+
+struct dcrypt_raw_key {
+	const void *parameter;
+	size_t len;
+};
+
+ARRAY_DEFINE_TYPE(dcrypt_raw_key, struct dcrypt_raw_key);
+
+/**
+ * load and initialize dcrypt backend, use either openssl or gnutls
+ */
+bool dcrypt_initialize(const char *backend, const struct dcrypt_settings *set,
+		       const char **error_r);
+
+/**
+ * Returns TRUE if dcrypt has been initialized.
+ */
+bool dcrypt_is_initialized(void);
+
+/**
+ * deinitialize dcrypt.
+ *
+ * NOTE: Do not call this function if you are going to use dcrypt later on.
+ * Deinitializing the library using this will not allow it to be reinitialized
+ * when using OpenSSL.
+ */
+void dcrypt_deinitialize(void);
+
+/**
+ * create symmetric context
+ */
+bool dcrypt_ctx_sym_create(const char *algorithm, enum dcrypt_sym_mode mode,
+			   struct dcrypt_context_symmetric **ctx_r,
+			   const char **error_r);
+
+/**
+ * destroy symmetric context and free memory
+ */
+void dcrypt_ctx_sym_destroy(struct dcrypt_context_symmetric **ctx);
+
+/**
+ * key and IV manipulation functions
+ */
+void dcrypt_ctx_sym_set_key(struct dcrypt_context_symmetric *ctx,
+			    const unsigned char *key, size_t key_len);
+void dcrypt_ctx_sym_set_iv(struct dcrypt_context_symmetric *ctx,
+			   const unsigned char *iv, size_t iv_len);
+void dcrypt_ctx_sym_set_key_iv_random(struct dcrypt_context_symmetric *ctx);
+bool dcrypt_ctx_sym_get_key(struct dcrypt_context_symmetric *ctx, buffer_t *key);
+bool dcrypt_ctx_sym_get_iv(struct dcrypt_context_symmetric *ctx, buffer_t *iv);
+
+/**
+ * turn padding on/off (default: on)
+ */
+void dcrypt_ctx_sym_set_padding(struct dcrypt_context_symmetric *ctx,
+				bool padding);
+
+/**
+ * authentication data manipulation (use with GCM only)
+ */
+void dcrypt_ctx_sym_set_aad(struct dcrypt_context_symmetric *ctx,
+			    const unsigned char *aad, size_t aad_len);
+bool dcrypt_ctx_sym_get_aad(struct dcrypt_context_symmetric *ctx,
+			    buffer_t *aad);
+/**
+ * result tag from aead (use with GCM only)
+ */
+void dcrypt_ctx_sym_set_tag(struct dcrypt_context_symmetric *ctx,
+			    const unsigned char *tag, size_t tag_len);
+bool dcrypt_ctx_sym_get_tag(struct dcrypt_context_symmetric *ctx,
+			    buffer_t *tag);
+
+/* get various lengths */
+unsigned int dcrypt_ctx_sym_get_key_length(struct dcrypt_context_symmetric *ctx);
+unsigned int dcrypt_ctx_sym_get_iv_length(struct dcrypt_context_symmetric *ctx);
+unsigned int dcrypt_ctx_sym_get_block_size(struct dcrypt_context_symmetric *ctx);
+
+/**
+ * initialize crypto
+ */
+bool dcrypt_ctx_sym_init(struct dcrypt_context_symmetric *ctx,
+			 const char **error_r);
+
+/**
+ * update with data
+ */
+bool dcrypt_ctx_sym_update(struct dcrypt_context_symmetric *ctx,
+			   const unsigned char *data, size_t data_len,
+			   buffer_t *result, const char **error_r);
+
+/**
+ * perform final step (may or may not emit data)
+ */
+bool dcrypt_ctx_sym_final(struct dcrypt_context_symmetric *ctx,
+			  buffer_t *result, const char **error_r);
+
+/**
+ * create HMAC context, algorithm is digest algorithm
+ */
+bool dcrypt_ctx_hmac_create(const char *algorithm,
+			    struct dcrypt_context_hmac **ctx_r,
+			    const char **error_r);
+/**
+ * destroy HMAC context and free memory
+ */
+void dcrypt_ctx_hmac_destroy(struct dcrypt_context_hmac **ctx);
+
+/**
+ * hmac key manipulation
+ */
+void dcrypt_ctx_hmac_set_key(struct dcrypt_context_hmac *ctx,
+			     const unsigned char *key, size_t key_len);
+bool dcrypt_ctx_hmac_get_key(struct dcrypt_context_hmac *ctx, buffer_t *key);
+void dcrypt_ctx_hmac_set_key_random(struct dcrypt_context_hmac *ctx);
+
+/**
+ * get digest length for HMAC
+ */
+unsigned int dcrypt_ctx_hmac_get_digest_length(struct dcrypt_context_hmac *ctx);
+
+/**
+ * initialize hmac
+ */
+bool dcrypt_ctx_hmac_init(struct dcrypt_context_hmac *ctx,
+			  const char **error_r);
+
+/**
+ * update hmac context with data
+ */
+bool dcrypt_ctx_hmac_update(struct dcrypt_context_hmac *ctx,
+			    const unsigned char *data, size_t data_len,
+			    const char **error_r);
+
+/**
+ * perform final rounds and retrieve result
+ */
+bool dcrypt_ctx_hmac_final(struct dcrypt_context_hmac *ctx, buffer_t *result,
+			   const char **error_r);
+
+/**
+ * Elliptic Curve based Diffie-Heffman shared secret derivation */
+bool dcrypt_ecdh_derive_secret(struct dcrypt_private_key *priv_key,
+			       struct dcrypt_public_key *pub_key,
+			       buffer_t *shared_secret,
+			       const char **error_r);
+/**
+ * Helpers for DCRYPT file format */
+bool dcrypt_ecdh_derive_secret_local(struct dcrypt_private_key *local_key,
+				     buffer_t *R, buffer_t *S,
+				     const char **error_r);
+bool dcrypt_ecdh_derive_secret_peer(struct dcrypt_public_key *peer_key,
+				    buffer_t *R, buffer_t *S,
+				    const char **error_r);
+
+/** Signature functions
+  algorithm is name of digest algorithm to use, such as SHA256.
+
+  both RSA and EC keys are supported.
+*/
+
+/* returns false on error, true on success */
+bool dcrypt_sign(struct dcrypt_private_key *key, const char *algorithm,
+		 enum dcrypt_signature_format format,
+		 const void *data, size_t data_len, buffer_t *signature_r,
+		 enum dcrypt_padding padding, const char **error_r);
+
+/* check valid_r for signature validity
+   false return means it wasn't able to verify it for other reasons */
+bool dcrypt_verify(struct dcrypt_public_key *key, const char *algorithm,
+		   enum dcrypt_signature_format format,
+		   const void *data, size_t data_len,
+		   const unsigned char *signature, size_t signature_len,
+		   bool *valid_r, enum dcrypt_padding padding,
+		   const char **error_r);
+
+/**
+ * generate cryptographic data from password and salt. Use 1000-10000 for rounds.
+ */
+bool dcrypt_pbkdf2(const unsigned char *password, size_t password_len,
+		   const unsigned char *salt, size_t salt_len,
+		   const char *hash, unsigned int rounds,
+		   buffer_t *result, unsigned int result_len,
+		   const char **error_r);
+
+bool dcrypt_keypair_generate(struct dcrypt_keypair *pair_r,
+			     enum dcrypt_key_type kind, unsigned int bits,
+			     const char *curve, const char **error_r);
+
+/**
+ * load loads key structure from external format.
+ * store stores key structure into external format.
+ *
+ * you can provide either PASSWORD or ENC_KEY, not both.
+ */
+bool dcrypt_key_load_private(struct dcrypt_private_key **key_r,
+			     const char *data, const char *password,
+			     struct dcrypt_private_key *dec_key,
+			     const char **error_r);
+
+bool dcrypt_key_load_public(struct dcrypt_public_key **key_r,
+			    const char *data, const char **error_r);
+
+/**
+ * When encrypting with public key, the cipher parameter here must begin with
+ * ecdh-, for example ecdh-aes-256-ctr. An example of a valid cipher for
+ * encrypting with password would be aes-256-ctr.
+ */
+bool dcrypt_key_store_private(struct dcrypt_private_key *key,
+			      enum dcrypt_key_format format, const char *cipher,
+			      buffer_t *destination, const char *password,
+			      struct dcrypt_public_key *enc_key,
+			      const char **error_r);
+
+bool dcrypt_key_store_public(struct dcrypt_public_key *key,
+			     enum dcrypt_key_format format,
+			     buffer_t *destination, const char **error_r);
+
+void dcrypt_key_convert_private_to_public(struct dcrypt_private_key *priv_key,
+					  struct dcrypt_public_key **pub_key_r);
+
+void dcrypt_keypair_unref(struct dcrypt_keypair *keypair);
+void dcrypt_key_ref_public(struct dcrypt_public_key *key);
+void dcrypt_key_ref_private(struct dcrypt_private_key *key);
+void dcrypt_key_unref_public(struct dcrypt_public_key **key);
+void dcrypt_key_unref_private(struct dcrypt_private_key **key);
+
+enum dcrypt_key_type dcrypt_key_type_private(struct dcrypt_private_key *key);
+enum dcrypt_key_type dcrypt_key_type_public(struct dcrypt_public_key *key);
+/* return digest of key */
+bool dcrypt_key_id_public(struct dcrypt_public_key *key, const char *algorithm,
+			  buffer_t *result, const char **error_r);
+/* return SHA1 sum of key */
+bool dcrypt_key_id_public_old(struct dcrypt_public_key *key, buffer_t *result,
+			      const char **error_r);
+/* return digest of key */
+bool dcrypt_key_id_private(struct dcrypt_private_key *key,
+			   const char *algorithm, buffer_t *result,
+			   const char **error_r);
+/* return SHA1 sum of key */
+bool dcrypt_key_id_private_old(struct dcrypt_private_key *key,
+			       buffer_t *result, const char **error_r);
+
+/* return raw private key:
+   Only ECC supported currently
+
+   returns OID bytes and private key in bigendian bytes
+*/
+bool dcrypt_key_store_private_raw(struct dcrypt_private_key *key,
+				  pool_t pool,
+				  enum dcrypt_key_type *key_type_r,
+				  ARRAY_TYPE(dcrypt_raw_key) *keys_r,
+				  const char **error_r);
+
+/* return raw public key
+   Only ECC supported currently
+
+   returns OID bytes and public key in compressed form (z||x)
+*/
+bool dcrypt_key_store_public_raw(struct dcrypt_public_key *key,
+				 pool_t pool,
+				 enum dcrypt_key_type *key_type_r,
+				 ARRAY_TYPE(dcrypt_raw_key) *keys_r,
+				 const char **error_r);
+
+/* load raw private key:
+   Only ECC supported currently
+
+   expects OID bytes and private key in bigendian bytes
+*/
+bool dcrypt_key_load_private_raw(struct dcrypt_private_key **key_r,
+				 enum dcrypt_key_type key_type,
+				 const ARRAY_TYPE(dcrypt_raw_key) *keys,
+				 const char **error_r);
+
+/* load raw public key
+   Only ECC supported currently
+
+   expects OID bytes and public key bytes.
+*/
+bool dcrypt_key_load_public_raw(struct dcrypt_public_key **key_r,
+				enum dcrypt_key_type key_type,
+				const ARRAY_TYPE(dcrypt_raw_key) *keys,
+				const char **error_r);
+
+/* for ECC only - return textual name or OID of used curve */
+bool dcrypt_key_get_curve_public(struct dcrypt_public_key *key,
+				 const char **curve_r, const char **error_r);
+
+bool dcrypt_key_string_get_info(const char *key_data,
+				enum dcrypt_key_format *format_r,
+				enum dcrypt_key_version *version_r,
+				enum dcrypt_key_kind *kind_r,
+				enum dcrypt_key_encryption_type *encryption_type_r,
+				const char **encryption_key_hash_r,
+				const char **key_hash_r, const char **error_r);
+
+/* Get/Set key identifier, this is optional opaque string identifying the key. */
+const char *dcrypt_key_get_id_public(struct dcrypt_public_key *key);
+const char *dcrypt_key_get_id_private(struct dcrypt_private_key *key);
+void dcrypt_key_set_id_public(struct dcrypt_public_key *key, const char *id);
+void dcrypt_key_set_id_private(struct dcrypt_private_key *key, const char *id);
+
+/* Get/Set key usage, optional. Defaults to NONE */
+enum dcrypt_key_usage dcrypt_key_get_usage_public(struct dcrypt_public_key *key);
+enum dcrypt_key_usage dcrypt_key_get_usage_private(struct dcrypt_private_key *key);
+void dcrypt_key_set_usage_public(struct dcrypt_public_key *key,
+				 enum dcrypt_key_usage usage);
+void dcrypt_key_set_usage_private(struct dcrypt_private_key *key,
+				  enum dcrypt_key_usage usage);
+
+/* RSA stuff */
+bool dcrypt_rsa_encrypt(struct dcrypt_public_key *key,
+			const unsigned char *data, size_t data_len,
+			buffer_t *result, enum dcrypt_padding padding,
+			const char **error_r);
+bool dcrypt_rsa_decrypt(struct dcrypt_private_key *key,
+			const unsigned char *data, size_t data_len,
+			buffer_t *result, enum dcrypt_padding padding,
+			const char **error_r);
+
+/* OID stuff */
+const char *dcrypt_oid2name(const unsigned char *oid, size_t oid_len,
+			    const char **error_r);
+bool dcrypt_name2oid(const char *name, buffer_t *oid, const char **error_r);
+
+#endif