1 files changed, 147 insertions, 0 deletions
diff --git a/src/auth/password-scheme.h b/src/auth/password-scheme.h
new file mode 100644
index 0000000..b3c3f56
--- /dev/null
+++ b/src/auth/password-scheme.h
@@ -0,0 +1,147 @@
+#ifndef PASSWORD_SCHEME_H
+#define PASSWORD_SCHEME_H
+
+#define AUTH_LOG_MSG_PASSWORD_MISMATCH "Password mismatch"
+
+struct hash_method;
+
+enum password_encoding {
+	PW_ENCODING_NONE,
+	PW_ENCODING_BASE64,
+	PW_ENCODING_HEX
+};
+
+struct password_generate_params {
+	const char *user;
+	unsigned int rounds;
+};
+
+struct password_scheme {
+	const char *name;
+	enum password_encoding default_encoding;
+	/* If non-zero, this is the expected raw password length.
+	   It can be used to automatically detect encoding between
+	   hex and base64 encoded passwords. */
+	unsigned int raw_password_len;
+
+	int (*password_verify)(const char *plaintext,
+			       const struct password_generate_params *params,
+			       const unsigned char *raw_password, size_t size,
+			       const char **error_r);
+	void (*password_generate)(const char *plaintext,
+				  const struct password_generate_params *params,
+				  const unsigned char **raw_password_r,
+				  size_t *size_r);
+};
+ARRAY_DEFINE_TYPE(password_scheme_p, const struct password_scheme *);
+void password_schemes_get(ARRAY_TYPE(password_scheme_p) *schemes_r);
+
+extern unsigned int password_scheme_encryption_rounds;
+
+/* Returns 1 = matched, 0 = didn't match, -1 = unknown scheme or invalid
+   raw_password */
+int password_verify(const char *plaintext,
+		    const struct password_generate_params *params,
+		    const char *scheme,
+		    const unsigned char *raw_password, size_t size,
+		    const char **error_r);
+
+/* Extracts scheme from password, or returns NULL if it isn't found.
+   If auth_request is given, it's used for debug logging. */
+const char *password_get_scheme(const char **password);
+
+/* Decode encoded (base64/hex) password to raw form. Returns 1 if ok,
+   0 if scheme is unknown, -1 if password is invalid. */
+int password_decode(const char *password, const char *scheme,
+		    const unsigned char **raw_password_r, size_t *size_r,
+		    const char **error_r);
+
+/* Create password with wanted scheme out of plaintext password and username.
+   Potential base64/hex directives are ignored in scheme. Returns FALSE if
+   the scheme is unknown. */
+bool password_generate(const char *plaintext,
+		       const struct password_generate_params *params,
+		       const char *scheme,
+		       const unsigned char **raw_password_r, size_t *size_r);
+/* Like above, but generate encoded passwords. If hex/base64 directive isn't
+   specified in the scheme, the default encoding for the scheme is used.
+   Returns FALSE if the scheme is unknown. */
+bool password_generate_encoded(const char *plaintext,
+			       const struct password_generate_params *params,
+			       const char *scheme, const char **password_r);
+
+/* Returns TRUE if schemes are equivalent. */
+bool password_scheme_is_alias(const char *scheme1, const char *scheme2);
+
+/* Try to detect in which scheme crypted password is. Returns the scheme name
+   or NULL if nothing was found. */
+const char *
+password_scheme_detect(const char *plain_password, const char *crypted_password,
+		       const struct password_generate_params *params);
+
+void password_scheme_register(const struct password_scheme *scheme);
+void password_scheme_unregister(const struct password_scheme *scheme);
+
+void password_schemes_init(void);
+void password_schemes_deinit(void);
+
+/* some password schemes/algorithms supports a variable number of
+   encryption rounds. */
+void password_set_encryption_rounds(unsigned int rounds);
+
+/* INTERNAL: */
+const char *password_generate_salt(size_t len);
+const char *password_generate_md5_crypt(const char *pw, const char *salt);
+int password_generate_otp(const char *pw, const char *state_data,
+			  unsigned int algo, const char **result_r)
+	ATTR_NULL(2);
+
+int crypt_verify(const char *plaintext,
+		 const struct password_generate_params *params,
+		 const unsigned char *raw_password, size_t size,
+		 const char **error_r);
+
+int scram_scheme_parse(const struct hash_method *hmethod, const char *name,
+		       const unsigned char *credentials, size_t size,
+		       unsigned int *iter_count_r, const char **salt_r,
+		       unsigned char stored_key_r[],
+		       unsigned char server_key_r[], const char **error_r);
+int scram_verify(const struct hash_method *hmethod, const char *scheme_name,
+		 const char *plaintext, const unsigned char *raw_password,
+		 size_t size, const char **error_r);
+void scram_generate(const struct hash_method *hmethod, const char *plaintext,
+		    const unsigned char **raw_password_r, size_t *size_r);
+
+int scram_sha1_verify(const char *plaintext,
+		      const struct password_generate_params *params ATTR_UNUSED,
+		      const unsigned char *raw_password, size_t size,
+		      const char **error_r ATTR_UNUSED);
+void scram_sha1_generate(const char *plaintext,
+			 const struct password_generate_params *params ATTR_UNUSED,
+			 const unsigned char **raw_password_r, size_t *size_r);
+
+int scram_sha256_verify(const char *plaintext,
+			const struct password_generate_params *params ATTR_UNUSED,
+			const unsigned char *raw_password, size_t size,
+			const char **error_r);
+void scram_sha256_generate(const char *plaintext,
+			   const struct password_generate_params *params ATTR_UNUSED,
+			   const unsigned char **raw_password_r, size_t *size_r);
+
+void pbkdf2_generate(const char *plaintext,
+		     const struct password_generate_params *params ATTR_UNUSED,
+		     const unsigned char **raw_password_r, size_t *size_r);
+int pbkdf2_verify(const char *plaintext,
+		  const struct password_generate_params *params ATTR_UNUSED,
+		  const unsigned char *raw_password, size_t size,
+		  const char **error_r);
+
+/* check which of the algorithms Blowfish, SHA-256 and SHA-512 are
+   supported by the used libc's/glibc's crypt() */
+void password_scheme_register_crypt(void);
+
+#ifdef HAVE_LIBSODIUM
+void password_scheme_register_sodium(void);
+#endif
+
+#endif