hs: Define INTRODUCE_ACK status code in trunnel

Remove the hs_intro_ack_status_t enum and move the value into trunnel. Only
use these values from now on in the intro point code.

Interestingly enough, the client side also re-define these values in hs_cell.h
with the hs_cell_introd_ack_status_t enum. Next commit will fix that and force
to use the trunnel ABI.

Part of #30454

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

3 files changed, 18 insertions, 7 deletions

diff --git a/src/trunnel/hs/cell_introduce1.c b/src/trunnel/hs/cell_introduce1.c
index 358b355cda..b93add64c8 100644
--- a/src/trunnel/hs/cell_introduce1.c
+++ b/src/trunnel/hs/cell_introduce1.c
@@ -519,6 +519,7 @@ trn_cell_introduce_ack_new(void)
   trn_cell_introduce_ack_t *val = trunnel_calloc(1, sizeof(trn_cell_introduce_ack_t));
   if (NULL == val)
     return NULL;
+  val->status = TRUNNEL_HS_INTRO_ACK_STATUS_BAD_FORMAT;
   return val;
 }
 
@@ -550,7 +551,7 @@ trn_cell_introduce_ack_get_status(const trn_cell_introduce_ack_t *inp)
 int
 trn_cell_introduce_ack_set_status(trn_cell_introduce_ack_t *inp, uint16_t val)
 {
-  if (! ((val == 0 || val == 1 || val == 2))) {
+  if (! ((val == TRUNNEL_HS_INTRO_ACK_STATUS_BAD_FORMAT || val == TRUNNEL_HS_INTRO_ACK_STATUS_SUCCESS || val == TRUNNEL_HS_INTRO_ACK_STATUS_UNKNOWN_ID))) {
      TRUNNEL_SET_ERROR_CODE(inp);
      return -1;
   }
@@ -587,7 +588,7 @@ trn_cell_introduce_ack_check(const trn_cell_introduce_ack_t *obj)
     return "Object was NULL";
   if (obj->trunnel_error_code_)
     return "A set function failed on this object";
-  if (! (obj->status == 0 || obj->status == 1 || obj->status == 2))
+  if (! (obj->status == TRUNNEL_HS_INTRO_ACK_STATUS_BAD_FORMAT || obj->status == TRUNNEL_HS_INTRO_ACK_STATUS_SUCCESS || obj->status == TRUNNEL_HS_INTRO_ACK_STATUS_UNKNOWN_ID))
     return "Integer out of bounds";
   {
     const char *msg;
@@ -606,7 +607,7 @@ trn_cell_introduce_ack_encoded_len(const trn_cell_introduce_ack_t *obj)
      return -1;
 
 
-  /* Length of u16 status IN [0, 1, 2] */
+  /* Length of u16 status IN [TRUNNEL_HS_INTRO_ACK_STATUS_BAD_FORMAT, TRUNNEL_HS_INTRO_ACK_STATUS_SUCCESS, TRUNNEL_HS_INTRO_ACK_STATUS_UNKNOWN_ID] */
   result += 2;
 
   /* Length of struct trn_cell_extension extensions */
@@ -638,7 +639,7 @@ trn_cell_introduce_ack_encode(uint8_t *output, const size_t avail, const trn_cel
   trunnel_assert(encoded_len >= 0);
 #endif
 
-  /* Encode u16 status IN [0, 1, 2] */
+  /* Encode u16 status IN [TRUNNEL_HS_INTRO_ACK_STATUS_BAD_FORMAT, TRUNNEL_HS_INTRO_ACK_STATUS_SUCCESS, TRUNNEL_HS_INTRO_ACK_STATUS_UNKNOWN_ID] */
   trunnel_assert(written <= avail);
   if (avail - written < 2)
     goto truncated;
@@ -687,11 +688,11 @@ trn_cell_introduce_ack_parse_into(trn_cell_introduce_ack_t *obj, const uint8_t *
   ssize_t result = 0;
   (void)result;
 
-  /* Parse u16 status IN [0, 1, 2] */
+  /* Parse u16 status IN [TRUNNEL_HS_INTRO_ACK_STATUS_BAD_FORMAT, TRUNNEL_HS_INTRO_ACK_STATUS_SUCCESS, TRUNNEL_HS_INTRO_ACK_STATUS_UNKNOWN_ID] */
   CHECK_REMAINING(2, truncated);
   obj->status = trunnel_ntohs(trunnel_get_uint16(ptr));
   remaining -= 2; ptr += 2;
-  if (! (obj->status == 0 || obj->status == 1 || obj->status == 2))
+  if (! (obj->status == TRUNNEL_HS_INTRO_ACK_STATUS_BAD_FORMAT || obj->status == TRUNNEL_HS_INTRO_ACK_STATUS_SUCCESS || obj->status == TRUNNEL_HS_INTRO_ACK_STATUS_UNKNOWN_ID))
     goto fail;
 
   /* Parse struct trn_cell_extension extensions */
diff --git a/src/trunnel/hs/cell_introduce1.h b/src/trunnel/hs/cell_introduce1.h
index fa218adc6d..1bec014b6f 100644
--- a/src/trunnel/hs/cell_introduce1.h
+++ b/src/trunnel/hs/cell_introduce1.h
@@ -12,6 +12,9 @@ struct trn_cell_extension_st;
 struct link_specifier_st;
 #define TRUNNEL_SHA1_LEN 20
 #define TRUNNEL_REND_COOKIE_LEN 20
+#define TRUNNEL_HS_INTRO_ACK_STATUS_SUCCESS 0
+#define TRUNNEL_HS_INTRO_ACK_STATUS_UNKNOWN_ID 1
+#define TRUNNEL_HS_INTRO_ACK_STATUS_BAD_FORMAT 2
 #if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_TRN_CELL_INTRODUCE1)
 struct trn_cell_introduce1_st {
   uint8_t legacy_key_id[TRUNNEL_SHA1_LEN];
diff --git a/src/trunnel/hs/cell_introduce1.trunnel b/src/trunnel/hs/cell_introduce1.trunnel
index 574382b163..6d924058f9 100644
--- a/src/trunnel/hs/cell_introduce1.trunnel
+++ b/src/trunnel/hs/cell_introduce1.trunnel
@@ -12,6 +12,11 @@ extern struct link_specifier;
 const TRUNNEL_SHA1_LEN = 20;
 const TRUNNEL_REND_COOKIE_LEN = 20;
 
+/* Introduce ACK status code. */
+const TRUNNEL_HS_INTRO_ACK_STATUS_SUCCESS    = 0x0000;
+const TRUNNEL_HS_INTRO_ACK_STATUS_UNKNOWN_ID = 0x0001;
+const TRUNNEL_HS_INTRO_ACK_STATUS_BAD_FORMAT = 0x0002;
+
 /* INTRODUCE1 payload. See details in section 3.2.1. */
 struct trn_cell_introduce1 {
   /* Always zeroed. MUST be checked explicitly by the caller. */
@@ -32,7 +37,9 @@ struct trn_cell_introduce1 {
 /* INTRODUCE_ACK payload. See details in section 3.2.2. */
 struct trn_cell_introduce_ack {
   /* Status of introduction. */
-  u16 status IN [0x0000, 0x0001, 0x0002];
+  u16 status IN [TRUNNEL_HS_INTRO_ACK_STATUS_SUCCESS,
+                 TRUNNEL_HS_INTRO_ACK_STATUS_UNKNOWN_ID,
+                 TRUNNEL_HS_INTRO_ACK_STATUS_BAD_FORMAT];
 
   /* Extension(s). Reserved fields. */
   struct trn_cell_extension extensions;