prop224: Add INTRODUCE1 and INTRODUCE_ACK trunnel definition

Signed-off-by: David Goulet <dgoulet@torproject.org>

1 files changed, 60 insertions, 0 deletions

diff --git a/src/trunnel/hs/cell_introduce1.trunnel b/src/trunnel/hs/cell_introduce1.trunnel
new file mode 100644
index 0000000000..f7776879cd
--- /dev/null
+++ b/src/trunnel/hs/cell_introduce1.trunnel
@@ -0,0 +1,60 @@
+/*
+ * This contains the definition of the INTRODUCE1 and INTRODUCE_ACK cell for
+ * onion service version 3 and onward. The following format is specified in
+ * proposal 224 section 3.2.
+ */
+
+/* From cell_common.trunnel. */
+extern struct cell_extension;
+/* From ed25519_cert.trunnel. */
+extern struct link_specifier;
+
+const TRUNNEL_SHA1_LEN = 20;
+const TRUNNEL_REND_COOKIE_LEN = 20;
+
+/* INTRODUCE1 payload. See details in section 3.2.1. */
+struct hs_cell_introduce1 {
+  /* Always zeroed. MUST be checked explicitely by the caller. */
+  u8 legacy_key_id[TRUNNEL_SHA1_LEN];
+
+  /* Authentication key material. */
+  u8 auth_key_type IN [0x00, 0x01, 0x02];
+  u16 auth_key_len;
+  u8 auth_key[auth_key_len];
+
+  /* Extension(s). Reserved fields. */
+  struct cell_extension extensions;
+
+  /* Variable length, up to the end of cell. */
+  u8 encrypted[];
+};
+
+/* INTRODUCE_ACK payload. See details in section 3.2.2. */
+struct hs_cell_introduce_ack {
+  /* Status of introduction. */
+  u16 status IN [0x0000, 0x0001, 0x0002];
+
+  /* Extension(s). Reserved fields. */
+  struct cell_extension extensions;
+};
+
+/* Encrypted section of the INTRODUCE1/INTRODUCE2 cell. */
+struct hs_cell_introduce_encrypted {
+  /* Rendezvous cookie. */
+  u8 rend_cookie[TRUNNEL_REND_COOKIE_LEN];
+
+  /* Extension(s). Reserved fields. */
+  struct cell_extension extensions;
+
+  /* Onion key material. */
+  u8 onion_key_type IN [0x01];
+  u16 onion_key_len;
+  u8 onion_key[onion_key_len];
+
+  /* Link specifiers(s) */
+  u8 nspec;
+  struct link_specifier nspecs[nspec];
+
+  /* Optional padding. This might be empty or not. */
+  u8 pad[];
+};