prop224: Add INTRODUCE1 and INTRODUCE_ACK trunnel definition

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

src/trunnel/hs/cell_introduce1.c

+/* cell_introduce1.c -- generated by Trunnel v1.5.
+ * https://gitweb.torproject.org/trunnel.git
+ * You probably shouldn't edit this file.
+ */
+#include <stdlib.h>
+#include "trunnel-impl.h"
+
+#include "cell_introduce1.h"
+
+#define TRUNNEL_SET_ERROR_CODE(obj) \
+  do {                              \
+    (obj)->trunnel_error_code_ = 1; \
+  } while (0)
+
+#if defined(__COVERITY__) || defined(__clang_analyzer__)
+/* If we're runnning a static analysis tool, we don't want it to complain
+ * that some of our remaining-bytes checks are dead-code. */
+int cellintroduce_deadcode_dummy__ = 0;
+#define OR_DEADCODE_DUMMY || cellintroduce_deadcode_dummy__
+#else
+#define OR_DEADCODE_DUMMY
+#endif
+
+#define CHECK_REMAINING(nbytes, label)                           \
+  do {                                                           \
+    if (remaining < (nbytes) OR_DEADCODE_DUMMY) {                \
+      goto label;                                                \
+    }                                                            \
+  } while (0)
+
+typedef struct cell_extension_st cell_extension_t;
+cell_extension_t *cell_extension_new(void);
+void cell_extension_free(cell_extension_t *victim);
+ssize_t cell_extension_parse(cell_extension_t **output, const uint8_t *input, const size_t len_in);
+ssize_t cell_extension_encoded_len(const cell_extension_t *obj);
+ssize_t cell_extension_encode(uint8_t *output, size_t avail, const cell_extension_t *input);
+const char *cell_extension_check(const cell_extension_t *obj);
+int cell_extension_clear_errors(cell_extension_t *obj);
+typedef struct link_specifier_st link_specifier_t;
+link_specifier_t *link_specifier_new(void);
+void link_specifier_free(link_specifier_t *victim);
+ssize_t link_specifier_parse(link_specifier_t **output, const uint8_t *input, const size_t len_in);
+ssize_t link_specifier_encoded_len(const link_specifier_t *obj);
+ssize_t link_specifier_encode(uint8_t *output, size_t avail, const link_specifier_t *input);
+const char *link_specifier_check(const link_specifier_t *obj);
+int link_specifier_clear_errors(link_specifier_t *obj);
+hs_cell_introduce1_t *
+hs_cell_introduce1_new(void)
+{
+  hs_cell_introduce1_t *val = trunnel_calloc(1, sizeof(hs_cell_introduce1_t));
+  if (NULL == val)
+    return NULL;
+  return val;
+}
+
+/** Release all storage held inside 'obj', but do not free 'obj'.
+ */
+static void
+hs_cell_introduce1_clear(hs_cell_introduce1_t *obj)
+{
+  (void) obj;
+  TRUNNEL_DYNARRAY_WIPE(&obj->auth_key);
+  TRUNNEL_DYNARRAY_CLEAR(&obj->auth_key);
+  cell_extension_free(obj->extensions);
+  obj->extensions = NULL;
+  TRUNNEL_DYNARRAY_WIPE(&obj->encrypted);
+  TRUNNEL_DYNARRAY_CLEAR(&obj->encrypted);
+}
+
+void
+hs_cell_introduce1_free(hs_cell_introduce1_t *obj)
+{
+  if (obj == NULL)
+    return;
+  hs_cell_introduce1_clear(obj);
+  trunnel_memwipe(obj, sizeof(hs_cell_introduce1_t));
+  trunnel_free_(obj);
+}
+
+size_t
+hs_cell_introduce1_getlen_legacy_key_id(const hs_cell_introduce1_t *inp)
+{
+  (void)inp;  return TRUNNEL_SHA1_LEN;
+}
+
+uint8_t
+hs_cell_introduce1_get_legacy_key_id(hs_cell_introduce1_t *inp, size_t idx)
+{
+  trunnel_assert(idx < TRUNNEL_SHA1_LEN);
+  return inp->legacy_key_id[idx];
+}
+
+uint8_t
+hs_cell_introduce1_getconst_legacy_key_id(const hs_cell_introduce1_t *inp, size_t idx)
+{
+  return hs_cell_introduce1_get_legacy_key_id((hs_cell_introduce1_t*)inp, idx);
+}
+int
+hs_cell_introduce1_set_legacy_key_id(hs_cell_introduce1_t *inp, size_t idx, uint8_t elt)
+{
+  trunnel_assert(idx < TRUNNEL_SHA1_LEN);
+  inp->legacy_key_id[idx] = elt;
+  return 0;
+}
+
+uint8_t *
+hs_cell_introduce1_getarray_legacy_key_id(hs_cell_introduce1_t *inp)
+{
+  return inp->legacy_key_id;
+}
+const uint8_t  *
+hs_cell_introduce1_getconstarray_legacy_key_id(const hs_cell_introduce1_t *inp)
+{
+  return (const uint8_t  *)hs_cell_introduce1_getarray_legacy_key_id((hs_cell_introduce1_t*)inp);
+}
+uint8_t
+hs_cell_introduce1_get_auth_key_type(hs_cell_introduce1_t *inp)
+{
+  return inp->auth_key_type;
+}
+int
+hs_cell_introduce1_set_auth_key_type(hs_cell_introduce1_t *inp, uint8_t val)
+{
+  if (! ((val == 0 || val == 1 || val == 2))) {
+     TRUNNEL_SET_ERROR_CODE(inp);
+     return -1;
+  }
+  inp->auth_key_type = val;
+  return 0;
+}
+uint16_t
+hs_cell_introduce1_get_auth_key_len(hs_cell_introduce1_t *inp)
+{
+  return inp->auth_key_len;
+}
+int
+hs_cell_introduce1_set_auth_key_len(hs_cell_introduce1_t *inp, uint16_t val)
+{
+  inp->auth_key_len = val;
+  return 0;
+}
+size_t
+hs_cell_introduce1_getlen_auth_key(const hs_cell_introduce1_t *inp)
+{
+  return TRUNNEL_DYNARRAY_LEN(&inp->auth_key);
+}
+
+uint8_t
+hs_cell_introduce1_get_auth_key(hs_cell_introduce1_t *inp, size_t idx)
+{
+  return TRUNNEL_DYNARRAY_GET(&inp->auth_key, idx);
+}
+
+uint8_t
+hs_cell_introduce1_getconst_auth_key(const hs_cell_introduce1_t *inp, size_t idx)
+{
+  return hs_cell_introduce1_get_auth_key((hs_cell_introduce1_t*)inp, idx);
+}
+int
+hs_cell_introduce1_set_auth_key(hs_cell_introduce1_t *inp, size_t idx, uint8_t elt)
+{
+  TRUNNEL_DYNARRAY_SET(&inp->auth_key, idx, elt);
+  return 0;
+}
+int
+hs_cell_introduce1_add_auth_key(hs_cell_introduce1_t *inp, uint8_t elt)
+{
+#if SIZE_MAX >= UINT16_MAX
+  if (inp->auth_key.n_ == UINT16_MAX)
+    goto trunnel_alloc_failed;
+#endif
+  TRUNNEL_DYNARRAY_ADD(uint8_t, &inp->auth_key, elt, {});
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+
+uint8_t *
+hs_cell_introduce1_getarray_auth_key(hs_cell_introduce1_t *inp)
+{
+  return inp->auth_key.elts_;
+}
+const uint8_t  *
+hs_cell_introduce1_getconstarray_auth_key(const hs_cell_introduce1_t *inp)
+{
+  return (const uint8_t  *)hs_cell_introduce1_getarray_auth_key((hs_cell_introduce1_t*)inp);
+}
+int
+hs_cell_introduce1_setlen_auth_key(hs_cell_introduce1_t *inp, size_t newlen)
+{
+  uint8_t *newptr;
+#if UINT16_MAX < SIZE_MAX
+  if (newlen > UINT16_MAX)
+    goto trunnel_alloc_failed;
+#endif
+  newptr = trunnel_dynarray_setlen(&inp->auth_key.allocated_,
+                 &inp->auth_key.n_, inp->auth_key.elts_, newlen,
+                 sizeof(inp->auth_key.elts_[0]), (trunnel_free_fn_t) NULL,
+                 &inp->trunnel_error_code_);
+  if (newlen != 0 && newptr == NULL)
+    goto trunnel_alloc_failed;
+  inp->auth_key.elts_ = newptr;
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+struct cell_extension_st *
+hs_cell_introduce1_get_extensions(hs_cell_introduce1_t *inp)
+{
+  return inp->extensions;
+}
+const struct cell_extension_st *
+hs_cell_introduce1_getconst_extensions(const hs_cell_introduce1_t *inp)
+{
+  return hs_cell_introduce1_get_extensions((hs_cell_introduce1_t*) inp);
+}
+int
+hs_cell_introduce1_set_extensions(hs_cell_introduce1_t *inp, struct cell_extension_st *val)
+{
+  if (inp->extensions && inp->extensions != val)
+    cell_extension_free(inp->extensions);
+  return hs_cell_introduce1_set0_extensions(inp, val);
+}
+int
+hs_cell_introduce1_set0_extensions(hs_cell_introduce1_t *inp, struct cell_extension_st *val)
+{
+  inp->extensions = val;
+  return 0;
+}
+size_t
+hs_cell_introduce1_getlen_encrypted(const hs_cell_introduce1_t *inp)
+{
+  return TRUNNEL_DYNARRAY_LEN(&inp->encrypted);
+}
+
+uint8_t
+hs_cell_introduce1_get_encrypted(hs_cell_introduce1_t *inp, size_t idx)
+{
+  return TRUNNEL_DYNARRAY_GET(&inp->encrypted, idx);
+}
+
+uint8_t
+hs_cell_introduce1_getconst_encrypted(const hs_cell_introduce1_t *inp, size_t idx)
+{
+  return hs_cell_introduce1_get_encrypted((hs_cell_introduce1_t*)inp, idx);
+}
+int
+hs_cell_introduce1_set_encrypted(hs_cell_introduce1_t *inp, size_t idx, uint8_t elt)
+{
+  TRUNNEL_DYNARRAY_SET(&inp->encrypted, idx, elt);
+  return 0;
+}
+int
+hs_cell_introduce1_add_encrypted(hs_cell_introduce1_t *inp, uint8_t elt)
+{
+  TRUNNEL_DYNARRAY_ADD(uint8_t, &inp->encrypted, elt, {});
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+
+uint8_t *
+hs_cell_introduce1_getarray_encrypted(hs_cell_introduce1_t *inp)
+{
+  return inp->encrypted.elts_;
+}
+const uint8_t  *
+hs_cell_introduce1_getconstarray_encrypted(const hs_cell_introduce1_t *inp)
+{
+  return (const uint8_t  *)hs_cell_introduce1_getarray_encrypted((hs_cell_introduce1_t*)inp);
+}
+int
+hs_cell_introduce1_setlen_encrypted(hs_cell_introduce1_t *inp, size_t newlen)
+{
+  uint8_t *newptr;
+  newptr = trunnel_dynarray_setlen(&inp->encrypted.allocated_,
+                 &inp->encrypted.n_, inp->encrypted.elts_, newlen,
+                 sizeof(inp->encrypted.elts_[0]), (trunnel_free_fn_t) NULL,
+                 &inp->trunnel_error_code_);
+  if (newlen != 0 && newptr == NULL)
+    goto trunnel_alloc_failed;
+  inp->encrypted.elts_ = newptr;
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+const char *
+hs_cell_introduce1_check(const hs_cell_introduce1_t *obj)
+{
+  if (obj == NULL)
+    return "Object was NULL";
+  if (obj->trunnel_error_code_)
+    return "A set function failed on this object";
+  if (! (obj->auth_key_type == 0 || obj->auth_key_type == 1 || obj->auth_key_type == 2))
+    return "Integer out of bounds";
+  if (TRUNNEL_DYNARRAY_LEN(&obj->auth_key) != obj->auth_key_len)
+    return "Length mismatch for auth_key";
+  {
+    const char *msg;
+    if (NULL != (msg = cell_extension_check(obj->extensions)))
+      return msg;
+  }
+  return NULL;
+}
+
+ssize_t
+hs_cell_introduce1_encoded_len(const hs_cell_introduce1_t *obj)
+{
+  ssize_t result = 0;
+
+  if (NULL != hs_cell_introduce1_check(obj))
+     return -1;
+
+
+  /* Length of u8 legacy_key_id[TRUNNEL_SHA1_LEN] */
+  result += TRUNNEL_SHA1_LEN;
+
+  /* Length of u8 auth_key_type IN [0, 1, 2] */
+  result += 1;
+
+  /* Length of u16 auth_key_len */
+  result += 2;
+
+  /* Length of u8 auth_key[auth_key_len] */
+  result += TRUNNEL_DYNARRAY_LEN(&obj->auth_key);
+
+  /* Length of struct cell_extension extensions */
+  result += cell_extension_encoded_len(obj->extensions);
+
+  /* Length of u8 encrypted[] */
+  result += TRUNNEL_DYNARRAY_LEN(&obj->encrypted);
+  return result;
+}
+int
+hs_cell_introduce1_clear_errors(hs_cell_introduce1_t *obj)
+{
+  int r = obj->trunnel_error_code_;
+  obj->trunnel_error_code_ = 0;
+  return r;
+}
+ssize_t
+hs_cell_introduce1_encode(uint8_t *output, const size_t avail, const hs_cell_introduce1_t *obj)
+{
+  ssize_t result = 0;
+  size_t written = 0;
+  uint8_t *ptr = output;
+  const char *msg;
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  const ssize_t encoded_len = hs_cell_introduce1_encoded_len(obj);
+#endif
+
+  if (NULL != (msg = hs_cell_introduce1_check(obj)))
+    goto check_failed;
+
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  trunnel_assert(encoded_len >= 0);
+#endif
+
+  /* Encode u8 legacy_key_id[TRUNNEL_SHA1_LEN] */
+  trunnel_assert(written <= avail);
+  if (avail - written < TRUNNEL_SHA1_LEN)
+    goto truncated;
+  memcpy(ptr, obj->legacy_key_id, TRUNNEL_SHA1_LEN);
+  written += TRUNNEL_SHA1_LEN; ptr += TRUNNEL_SHA1_LEN;
+
+  /* Encode u8 auth_key_type IN [0, 1, 2] */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->auth_key_type));
+  written += 1; ptr += 1;
+
+  /* Encode u16 auth_key_len */
+  trunnel_assert(written <= avail);
+  if (avail - written < 2)
+    goto truncated;
+  trunnel_set_uint16(ptr, trunnel_htons(obj->auth_key_len));
+  written += 2; ptr += 2;
+
+  /* Encode u8 auth_key[auth_key_len] */
+  {
+    size_t elt_len = TRUNNEL_DYNARRAY_LEN(&obj->auth_key);
+    trunnel_assert(obj->auth_key_len == elt_len);
+    trunnel_assert(written <= avail);
+    if (avail - written < elt_len)
+      goto truncated;
+    if (elt_len)
+      memcpy(ptr, obj->auth_key.elts_, elt_len);
+    written += elt_len; ptr += elt_len;
+  }
+
+  /* Encode struct cell_extension extensions */
+  trunnel_assert(written <= avail);
+  result = cell_extension_encode(ptr, avail - written, obj->extensions);
+  if (result < 0)
+    goto fail; /* XXXXXXX !*/
+  written += result; ptr += result;
+
+  /* Encode u8 encrypted[] */
+  {
+    size_t elt_len = TRUNNEL_DYNARRAY_LEN(&obj->encrypted);
+    trunnel_assert(written <= avail);
+    if (avail - written < elt_len)
+      goto truncated;
+    if (elt_len)
+      memcpy(ptr, obj->encrypted.elts_, elt_len);
+    written += elt_len; ptr += elt_len;
+  }
+
+
+  trunnel_assert(ptr == output + written);
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  {
+    trunnel_assert(encoded_len >= 0);
+    trunnel_assert((size_t)encoded_len == written);
+  }
+
+#endif
+
+  return written;
+
+ truncated:
+  result = -2;
+  goto fail;
+ check_failed:
+  (void)msg;
+  result = -1;
+  goto fail;
+ fail:
+  trunnel_assert(result < 0);
+  return result;
+}
+
+/** As hs_cell_introduce1_parse(), but do not allocate the output
+ * object.
+ */
+static ssize_t
+hs_cell_introduce1_parse_into(hs_cell_introduce1_t *obj, const uint8_t *input, const size_t len_in)
+{
+  const uint8_t *ptr = input;
+  size_t remaining = len_in;
+  ssize_t result = 0;
+  (void)result;
+
+  /* Parse u8 legacy_key_id[TRUNNEL_SHA1_LEN] */
+  CHECK_REMAINING(TRUNNEL_SHA1_LEN, truncated);
+  memcpy(obj->legacy_key_id, ptr, TRUNNEL_SHA1_LEN);
+  remaining -= TRUNNEL_SHA1_LEN; ptr += TRUNNEL_SHA1_LEN;
+
+  /* Parse u8 auth_key_type IN [0, 1, 2] */
+  CHECK_REMAINING(1, truncated);
+  obj->auth_key_type = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  if (! (obj->auth_key_type == 0 || obj->auth_key_type == 1 || obj->auth_key_type == 2))
+    goto fail;
+
+  /* Parse u16 auth_key_len */
+  CHECK_REMAINING(2, truncated);
+  obj->auth_key_len = trunnel_ntohs(trunnel_get_uint16(ptr));
+  remaining -= 2; ptr += 2;
+
+  /* Parse u8 auth_key[auth_key_len] */
+  CHECK_REMAINING(obj->auth_key_len, truncated);
+  TRUNNEL_DYNARRAY_EXPAND(uint8_t, &obj->auth_key, obj->auth_key_len, {});
+  obj->auth_key.n_ = obj->auth_key_len;
+  if (obj->auth_key_len)
+    memcpy(obj->auth_key.elts_, ptr, obj->auth_key_len);
+  ptr += obj->auth_key_len; remaining -= obj->auth_key_len;
+
+  /* Parse struct cell_extension extensions */
+  result = cell_extension_parse(&obj->extensions, ptr, remaining);
+  if (result < 0)
+    goto relay_fail;
+  trunnel_assert((size_t)result <= remaining);
+  remaining -= result; ptr += result;
+
+  /* Parse u8 encrypted[] */
+  TRUNNEL_DYNARRAY_EXPAND(uint8_t, &obj->encrypted, remaining, {});
+  obj->encrypted.n_ = remaining;
+  if (remaining)
+    memcpy(obj->encrypted.elts_, ptr, remaining);
+  ptr += remaining; remaining -= remaining;
+  trunnel_assert(ptr + remaining == input + len_in);
+  return len_in - remaining;
+
+ truncated:
+  return -2;
+ relay_fail:
+  trunnel_assert(result < 0);
+  return result;
+ trunnel_alloc_failed:
+  return -1;
+ fail:
+  result = -1;
+  return result;
+}
+
+ssize_t
+hs_cell_introduce1_parse(hs_cell_introduce1_t **output, const uint8_t *input, const size_t len_in)
+{
+  ssize_t result;
+  *output = hs_cell_introduce1_new();
+  if (NULL == *output)
+    return -1;
+  result = hs_cell_introduce1_parse_into(*output, input, len_in);
+  if (result < 0) {
+    hs_cell_introduce1_free(*output);
+    *output = NULL;
+  }
+  return result;
+}
+hs_cell_introduce_ack_t *
+hs_cell_introduce_ack_new(void)
+{
+  hs_cell_introduce_ack_t *val = trunnel_calloc(1, sizeof(hs_cell_introduce_ack_t));
+  if (NULL == val)
+    return NULL;
+  return val;
+}
+
+/** Release all storage held inside 'obj', but do not free 'obj'.
+ */
+static void
+hs_cell_introduce_ack_clear(hs_cell_introduce_ack_t *obj)
+{
+  (void) obj;
+  cell_extension_free(obj->extensions);
+  obj->extensions = NULL;
+}
+
+void
+hs_cell_introduce_ack_free(hs_cell_introduce_ack_t *obj)
+{
+  if (obj == NULL)
+    return;
+  hs_cell_introduce_ack_clear(obj);
+  trunnel_memwipe(obj, sizeof(hs_cell_introduce_ack_t));
+  trunnel_free_(obj);
+}
+
+uint16_t
+hs_cell_introduce_ack_get_status(hs_cell_introduce_ack_t *inp)
+{
+  return inp->status;
+}
+int
+hs_cell_introduce_ack_set_status(hs_cell_introduce_ack_t *inp, uint16_t val)
+{
+  if (! ((val == 0 || val == 1 || val == 2))) {
+     TRUNNEL_SET_ERROR_CODE(inp);
+     return -1;
+  }
+  inp->status = val;
+  return 0;
+}
+struct cell_extension_st *
+hs_cell_introduce_ack_get_extensions(hs_cell_introduce_ack_t *inp)
+{
+  return inp->extensions;
+}
+const struct cell_extension_st *
+hs_cell_introduce_ack_getconst_extensions(const hs_cell_introduce_ack_t *inp)
+{
+  return hs_cell_introduce_ack_get_extensions((hs_cell_introduce_ack_t*) inp);
+}
+int
+hs_cell_introduce_ack_set_extensions(hs_cell_introduce_ack_t *inp, struct cell_extension_st *val)
+{
+  if (inp->extensions && inp->extensions != val)
+    cell_extension_free(inp->extensions);
+  return hs_cell_introduce_ack_set0_extensions(inp, val);
+}
+int
+hs_cell_introduce_ack_set0_extensions(hs_cell_introduce_ack_t *inp, struct cell_extension_st *val)
+{
+  inp->extensions = val;
+  return 0;
+}
+const char *
+hs_cell_introduce_ack_check(const hs_cell_introduce_ack_t *obj)
+{
+  if (obj == NULL)
+    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))
+    return "Integer out of bounds";
+  {
+    const char *msg;
+    if (NULL != (msg = cell_extension_check(obj->extensions)))
+      return msg;
+  }
+  return NULL;
+}
+
+ssize_t
+hs_cell_introduce_ack_encoded_len(const hs_cell_introduce_ack_t *obj)
+{
+  ssize_t result = 0;
+
+  if (NULL != hs_cell_introduce_ack_check(obj))
+     return -1;
+
+
+  /* Length of u16 status IN [0, 1, 2] */
+  result += 2;
+
+  /* Length of struct cell_extension extensions */
+  result += cell_extension_encoded_len(obj->extensions);
+  return result;
+}
+int
+hs_cell_introduce_ack_clear_errors(hs_cell_introduce_ack_t *obj)
+{
+  int r = obj->trunnel_error_code_;
+  obj->trunnel_error_code_ = 0;
+  return r;
+}
+ssize_t
+hs_cell_introduce_ack_encode(uint8_t *output, const size_t avail, const hs_cell_introduce_ack_t *obj)
+{
+  ssize_t result = 0;
+  size_t written = 0;
+  uint8_t *ptr = output;
+  const char *msg;
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  const ssize_t encoded_len = hs_cell_introduce_ack_encoded_len(obj);
+#endif
+
+  if (NULL != (msg = hs_cell_introduce_ack_check(obj)))
+    goto check_failed;
+
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  trunnel_assert(encoded_len >= 0);
+#endif
+
+  /* Encode u16 status IN [0, 1, 2] */
+  trunnel_assert(written <= avail);
+  if (avail - written < 2)
+    goto truncated;
+  trunnel_set_uint16(ptr, trunnel_htons(obj->status));
+  written += 2; ptr += 2;
+
+  /* Encode struct cell_extension extensions */
+  trunnel_assert(written <= avail);
+  result = cell_extension_encode(ptr, avail - written, obj->extensions);
+  if (result < 0)
+    goto fail; /* XXXXXXX !*/
+  written += result; ptr += result;
+
+
+  trunnel_assert(ptr == output + written);
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  {
+    trunnel_assert(encoded_len >= 0);
+    trunnel_assert((size_t)encoded_len == written);
+  }
+
+#endif
+
+  return written;
+
+ truncated:
+  result = -2;
+  goto fail;
+ check_failed:
+  (void)msg;
+  result = -1;
+  goto fail;
+ fail:
+  trunnel_assert(result < 0);
+  return result;
+}
+
+/** As hs_cell_introduce_ack_parse(), but do not allocate the output
+ * object.
+ */
+static ssize_t
+hs_cell_introduce_ack_parse_into(hs_cell_introduce_ack_t *obj, const uint8_t *input, const size_t len_in)
+{
+  const uint8_t *ptr = input;
+  size_t remaining = len_in;
+  ssize_t result = 0;
+  (void)result;
+
+  /* Parse u16 status IN [0, 1, 2] */
+  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))
+    goto fail;
+
+  /* Parse struct cell_extension extensions */
+  result = cell_extension_parse(&obj->extensions, ptr, remaining);
+  if (result < 0)
+    goto relay_fail;
+  trunnel_assert((size_t)result <= remaining);
+  remaining -= result; ptr += result;
+  trunnel_assert(ptr + remaining == input + len_in);
+  return len_in - remaining;
+
+ truncated:
+  return -2;
+ relay_fail:
+  trunnel_assert(result < 0);
+  return result;
+ fail:
+  result = -1;
+  return result;
+}
+
+ssize_t
+hs_cell_introduce_ack_parse(hs_cell_introduce_ack_t **output, const uint8_t *input, const size_t len_in)
+{
+  ssize_t result;
+  *output = hs_cell_introduce_ack_new();
+  if (NULL == *output)
+    return -1;
+  result = hs_cell_introduce_ack_parse_into(*output, input, len_in);
+  if (result < 0) {
+    hs_cell_introduce_ack_free(*output);
+    *output = NULL;
+  }
+  return result;
+}
+hs_cell_introduce_encrypted_t *
+hs_cell_introduce_encrypted_new(void)
+{
+  hs_cell_introduce_encrypted_t *val = trunnel_calloc(1, sizeof(hs_cell_introduce_encrypted_t));
+  if (NULL == val)
+    return NULL;
+  return val;
+}
+
+/** Release all storage held inside 'obj', but do not free 'obj'.
+ */
+static void
+hs_cell_introduce_encrypted_clear(hs_cell_introduce_encrypted_t *obj)
+{
+  (void) obj;
+  cell_extension_free(obj->extensions);
+  obj->extensions = NULL;
+  TRUNNEL_DYNARRAY_WIPE(&obj->onion_key);
+  TRUNNEL_DYNARRAY_CLEAR(&obj->onion_key);
+  {
+
+    unsigned idx;
+    for (idx = 0; idx < TRUNNEL_DYNARRAY_LEN(&obj->nspecs); ++idx) {
+      link_specifier_free(TRUNNEL_DYNARRAY_GET(&obj->nspecs, idx));
+    }
+  }
+  TRUNNEL_DYNARRAY_WIPE(&obj->nspecs);
+  TRUNNEL_DYNARRAY_CLEAR(&obj->nspecs);
+  TRUNNEL_DYNARRAY_WIPE(&obj->pad);
+  TRUNNEL_DYNARRAY_CLEAR(&obj->pad);
+}
+
+void
+hs_cell_introduce_encrypted_free(hs_cell_introduce_encrypted_t *obj)
+{
+  if (obj == NULL)
+    return;
+  hs_cell_introduce_encrypted_clear(obj);
+  trunnel_memwipe(obj, sizeof(hs_cell_introduce_encrypted_t));
+  trunnel_free_(obj);
+}
+
+size_t
+hs_cell_introduce_encrypted_getlen_rend_cookie(const hs_cell_introduce_encrypted_t *inp)
+{
+  (void)inp;  return TRUNNEL_REND_COOKIE_LEN;
+}
+
+uint8_t
+hs_cell_introduce_encrypted_get_rend_cookie(hs_cell_introduce_encrypted_t *inp, size_t idx)
+{
+  trunnel_assert(idx < TRUNNEL_REND_COOKIE_LEN);
+  return inp->rend_cookie[idx];
+}
+
+uint8_t
+hs_cell_introduce_encrypted_getconst_rend_cookie(const hs_cell_introduce_encrypted_t *inp, size_t idx)
+{
+  return hs_cell_introduce_encrypted_get_rend_cookie((hs_cell_introduce_encrypted_t*)inp, idx);
+}
+int
+hs_cell_introduce_encrypted_set_rend_cookie(hs_cell_introduce_encrypted_t *inp, size_t idx, uint8_t elt)
+{
+  trunnel_assert(idx < TRUNNEL_REND_COOKIE_LEN);
+  inp->rend_cookie[idx] = elt;
+  return 0;
+}
+
+uint8_t *
+hs_cell_introduce_encrypted_getarray_rend_cookie(hs_cell_introduce_encrypted_t *inp)
+{
+  return inp->rend_cookie;
+}
+const uint8_t  *
+hs_cell_introduce_encrypted_getconstarray_rend_cookie(const hs_cell_introduce_encrypted_t *inp)
+{
+  return (const uint8_t  *)hs_cell_introduce_encrypted_getarray_rend_cookie((hs_cell_introduce_encrypted_t*)inp);
+}
+struct cell_extension_st *
+hs_cell_introduce_encrypted_get_extensions(hs_cell_introduce_encrypted_t *inp)
+{
+  return inp->extensions;
+}
+const struct cell_extension_st *
+hs_cell_introduce_encrypted_getconst_extensions(const hs_cell_introduce_encrypted_t *inp)
+{
+  return hs_cell_introduce_encrypted_get_extensions((hs_cell_introduce_encrypted_t*) inp);
+}
+int
+hs_cell_introduce_encrypted_set_extensions(hs_cell_introduce_encrypted_t *inp, struct cell_extension_st *val)
+{
+  if (inp->extensions && inp->extensions != val)
+    cell_extension_free(inp->extensions);
+  return hs_cell_introduce_encrypted_set0_extensions(inp, val);
+}
+int
+hs_cell_introduce_encrypted_set0_extensions(hs_cell_introduce_encrypted_t *inp, struct cell_extension_st *val)
+{
+  inp->extensions = val;
+  return 0;
+}
+uint8_t
+hs_cell_introduce_encrypted_get_onion_key_type(hs_cell_introduce_encrypted_t *inp)
+{
+  return inp->onion_key_type;
+}
+int
+hs_cell_introduce_encrypted_set_onion_key_type(hs_cell_introduce_encrypted_t *inp, uint8_t val)
+{
+  inp->onion_key_type = val;
+  return 0;
+}
+uint16_t
+hs_cell_introduce_encrypted_get_onion_key_len(hs_cell_introduce_encrypted_t *inp)
+{
+  return inp->onion_key_len;
+}
+int
+hs_cell_introduce_encrypted_set_onion_key_len(hs_cell_introduce_encrypted_t *inp, uint16_t val)
+{
+  inp->onion_key_len = val;
+  return 0;
+}
+size_t
+hs_cell_introduce_encrypted_getlen_onion_key(const hs_cell_introduce_encrypted_t *inp)
+{
+  return TRUNNEL_DYNARRAY_LEN(&inp->onion_key);
+}
+
+uint8_t
+hs_cell_introduce_encrypted_get_onion_key(hs_cell_introduce_encrypted_t *inp, size_t idx)
+{
+  return TRUNNEL_DYNARRAY_GET(&inp->onion_key, idx);
+}
+
+uint8_t
+hs_cell_introduce_encrypted_getconst_onion_key(const hs_cell_introduce_encrypted_t *inp, size_t idx)
+{
+  return hs_cell_introduce_encrypted_get_onion_key((hs_cell_introduce_encrypted_t*)inp, idx);
+}
+int
+hs_cell_introduce_encrypted_set_onion_key(hs_cell_introduce_encrypted_t *inp, size_t idx, uint8_t elt)
+{
+  TRUNNEL_DYNARRAY_SET(&inp->onion_key, idx, elt);
+  return 0;
+}
+int
+hs_cell_introduce_encrypted_add_onion_key(hs_cell_introduce_encrypted_t *inp, uint8_t elt)
+{
+#if SIZE_MAX >= UINT16_MAX
+  if (inp->onion_key.n_ == UINT16_MAX)
+    goto trunnel_alloc_failed;
+#endif
+  TRUNNEL_DYNARRAY_ADD(uint8_t, &inp->onion_key, elt, {});
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+
+uint8_t *
+hs_cell_introduce_encrypted_getarray_onion_key(hs_cell_introduce_encrypted_t *inp)
+{
+  return inp->onion_key.elts_;
+}
+const uint8_t  *
+hs_cell_introduce_encrypted_getconstarray_onion_key(const hs_cell_introduce_encrypted_t *inp)
+{
+  return (const uint8_t  *)hs_cell_introduce_encrypted_getarray_onion_key((hs_cell_introduce_encrypted_t*)inp);
+}
+int
+hs_cell_introduce_encrypted_setlen_onion_key(hs_cell_introduce_encrypted_t *inp, size_t newlen)
+{
+  uint8_t *newptr;
+#if UINT16_MAX < SIZE_MAX
+  if (newlen > UINT16_MAX)
+    goto trunnel_alloc_failed;
+#endif
+  newptr = trunnel_dynarray_setlen(&inp->onion_key.allocated_,
+                 &inp->onion_key.n_, inp->onion_key.elts_, newlen,
+                 sizeof(inp->onion_key.elts_[0]), (trunnel_free_fn_t) NULL,
+                 &inp->trunnel_error_code_);
+  if (newlen != 0 && newptr == NULL)
+    goto trunnel_alloc_failed;
+  inp->onion_key.elts_ = newptr;
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+uint8_t
+hs_cell_introduce_encrypted_get_nspec(hs_cell_introduce_encrypted_t *inp)
+{
+  return inp->nspec;
+}
+int
+hs_cell_introduce_encrypted_set_nspec(hs_cell_introduce_encrypted_t *inp, uint8_t val)
+{
+  inp->nspec = val;
+  return 0;
+}
+size_t
+hs_cell_introduce_encrypted_getlen_nspecs(const hs_cell_introduce_encrypted_t *inp)
+{
+  return TRUNNEL_DYNARRAY_LEN(&inp->nspecs);
+}
+
+struct link_specifier_st *
+hs_cell_introduce_encrypted_get_nspecs(hs_cell_introduce_encrypted_t *inp, size_t idx)
+{
+  return TRUNNEL_DYNARRAY_GET(&inp->nspecs, idx);
+}
+
+ const struct link_specifier_st *
+hs_cell_introduce_encrypted_getconst_nspecs(const hs_cell_introduce_encrypted_t *inp, size_t idx)
+{
+  return hs_cell_introduce_encrypted_get_nspecs((hs_cell_introduce_encrypted_t*)inp, idx);
+}
+int
+hs_cell_introduce_encrypted_set_nspecs(hs_cell_introduce_encrypted_t *inp, size_t idx, struct link_specifier_st * elt)
+{
+  link_specifier_t *oldval = TRUNNEL_DYNARRAY_GET(&inp->nspecs, idx);
+  if (oldval && oldval != elt)
+    link_specifier_free(oldval);
+  return hs_cell_introduce_encrypted_set0_nspecs(inp, idx, elt);
+}
+int
+hs_cell_introduce_encrypted_set0_nspecs(hs_cell_introduce_encrypted_t *inp, size_t idx, struct link_specifier_st * elt)
+{
+  TRUNNEL_DYNARRAY_SET(&inp->nspecs, idx, elt);
+  return 0;
+}
+int
+hs_cell_introduce_encrypted_add_nspecs(hs_cell_introduce_encrypted_t *inp, struct link_specifier_st * elt)
+{
+#if SIZE_MAX >= UINT8_MAX
+  if (inp->nspecs.n_ == UINT8_MAX)
+    goto trunnel_alloc_failed;
+#endif
+  TRUNNEL_DYNARRAY_ADD(struct link_specifier_st *, &inp->nspecs, elt, {});
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+
+struct link_specifier_st * *
+hs_cell_introduce_encrypted_getarray_nspecs(hs_cell_introduce_encrypted_t *inp)
+{
+  return inp->nspecs.elts_;
+}
+const struct link_specifier_st *  const  *
+hs_cell_introduce_encrypted_getconstarray_nspecs(const hs_cell_introduce_encrypted_t *inp)
+{
+  return (const struct link_specifier_st *  const  *)hs_cell_introduce_encrypted_getarray_nspecs((hs_cell_introduce_encrypted_t*)inp);
+}
+int
+hs_cell_introduce_encrypted_setlen_nspecs(hs_cell_introduce_encrypted_t *inp, size_t newlen)
+{
+  struct link_specifier_st * *newptr;
+#if UINT8_MAX < SIZE_MAX
+  if (newlen > UINT8_MAX)
+    goto trunnel_alloc_failed;
+#endif
+  newptr = trunnel_dynarray_setlen(&inp->nspecs.allocated_,
+                 &inp->nspecs.n_, inp->nspecs.elts_, newlen,
+                 sizeof(inp->nspecs.elts_[0]), (trunnel_free_fn_t) link_specifier_free,
+                 &inp->trunnel_error_code_);
+  if (newlen != 0 && newptr == NULL)
+    goto trunnel_alloc_failed;
+  inp->nspecs.elts_ = newptr;
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+size_t
+hs_cell_introduce_encrypted_getlen_pad(const hs_cell_introduce_encrypted_t *inp)
+{
+  return TRUNNEL_DYNARRAY_LEN(&inp->pad);
+}
+
+uint8_t
+hs_cell_introduce_encrypted_get_pad(hs_cell_introduce_encrypted_t *inp, size_t idx)
+{
+  return TRUNNEL_DYNARRAY_GET(&inp->pad, idx);
+}
+
+uint8_t
+hs_cell_introduce_encrypted_getconst_pad(const hs_cell_introduce_encrypted_t *inp, size_t idx)
+{
+  return hs_cell_introduce_encrypted_get_pad((hs_cell_introduce_encrypted_t*)inp, idx);
+}
+int
+hs_cell_introduce_encrypted_set_pad(hs_cell_introduce_encrypted_t *inp, size_t idx, uint8_t elt)
+{
+  TRUNNEL_DYNARRAY_SET(&inp->pad, idx, elt);
+  return 0;
+}
+int
+hs_cell_introduce_encrypted_add_pad(hs_cell_introduce_encrypted_t *inp, uint8_t elt)
+{
+  TRUNNEL_DYNARRAY_ADD(uint8_t, &inp->pad, elt, {});
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+
+uint8_t *
+hs_cell_introduce_encrypted_getarray_pad(hs_cell_introduce_encrypted_t *inp)
+{
+  return inp->pad.elts_;
+}
+const uint8_t  *
+hs_cell_introduce_encrypted_getconstarray_pad(const hs_cell_introduce_encrypted_t *inp)
+{
+  return (const uint8_t  *)hs_cell_introduce_encrypted_getarray_pad((hs_cell_introduce_encrypted_t*)inp);
+}
+int
+hs_cell_introduce_encrypted_setlen_pad(hs_cell_introduce_encrypted_t *inp, size_t newlen)
+{
+  uint8_t *newptr;
+  newptr = trunnel_dynarray_setlen(&inp->pad.allocated_,
+                 &inp->pad.n_, inp->pad.elts_, newlen,
+                 sizeof(inp->pad.elts_[0]), (trunnel_free_fn_t) NULL,
+                 &inp->trunnel_error_code_);
+  if (newlen != 0 && newptr == NULL)
+    goto trunnel_alloc_failed;
+  inp->pad.elts_ = newptr;
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+const char *
+hs_cell_introduce_encrypted_check(const hs_cell_introduce_encrypted_t *obj)
+{
+  if (obj == NULL)
+    return "Object was NULL";
+  if (obj->trunnel_error_code_)
+    return "A set function failed on this object";
+  {
+    const char *msg;
+    if (NULL != (msg = cell_extension_check(obj->extensions)))
+      return msg;
+  }
+  if (TRUNNEL_DYNARRAY_LEN(&obj->onion_key) != obj->onion_key_len)
+    return "Length mismatch for onion_key";
+  {
+    const char *msg;
+
+    unsigned idx;
+    for (idx = 0; idx < TRUNNEL_DYNARRAY_LEN(&obj->nspecs); ++idx) {
+      if (NULL != (msg = link_specifier_check(TRUNNEL_DYNARRAY_GET(&obj->nspecs, idx))))
+        return msg;
+    }
+  }
+  if (TRUNNEL_DYNARRAY_LEN(&obj->nspecs) != obj->nspec)
+    return "Length mismatch for nspecs";
+  return NULL;
+}
+
+ssize_t
+hs_cell_introduce_encrypted_encoded_len(const hs_cell_introduce_encrypted_t *obj)
+{
+  ssize_t result = 0;
+
+  if (NULL != hs_cell_introduce_encrypted_check(obj))
+     return -1;
+
+
+  /* Length of u8 rend_cookie[TRUNNEL_REND_COOKIE_LEN] */
+  result += TRUNNEL_REND_COOKIE_LEN;
+
+  /* Length of struct cell_extension extensions */
+  result += cell_extension_encoded_len(obj->extensions);
+
+  /* Length of u8 onion_key_type */
+  result += 1;
+
+  /* Length of u16 onion_key_len */
+  result += 2;
+
+  /* Length of u8 onion_key[onion_key_len] */
+  result += TRUNNEL_DYNARRAY_LEN(&obj->onion_key);
+
+  /* Length of u8 nspec */
+  result += 1;
+
+  /* Length of struct link_specifier nspecs[nspec] */
+  {
+
+    unsigned idx;
+    for (idx = 0; idx < TRUNNEL_DYNARRAY_LEN(&obj->nspecs); ++idx) {
+      result += link_specifier_encoded_len(TRUNNEL_DYNARRAY_GET(&obj->nspecs, idx));
+    }
+  }
+
+  /* Length of u8 pad[] */
+  result += TRUNNEL_DYNARRAY_LEN(&obj->pad);
+  return result;
+}
+int
+hs_cell_introduce_encrypted_clear_errors(hs_cell_introduce_encrypted_t *obj)
+{
+  int r = obj->trunnel_error_code_;
+  obj->trunnel_error_code_ = 0;
+  return r;
+}
+ssize_t
+hs_cell_introduce_encrypted_encode(uint8_t *output, const size_t avail, const hs_cell_introduce_encrypted_t *obj)
+{
+  ssize_t result = 0;
+  size_t written = 0;
+  uint8_t *ptr = output;
+  const char *msg;
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  const ssize_t encoded_len = hs_cell_introduce_encrypted_encoded_len(obj);
+#endif
+
+  if (NULL != (msg = hs_cell_introduce_encrypted_check(obj)))
+    goto check_failed;
+
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  trunnel_assert(encoded_len >= 0);
+#endif
+
+  /* Encode u8 rend_cookie[TRUNNEL_REND_COOKIE_LEN] */
+  trunnel_assert(written <= avail);
+  if (avail - written < TRUNNEL_REND_COOKIE_LEN)
+    goto truncated;
+  memcpy(ptr, obj->rend_cookie, TRUNNEL_REND_COOKIE_LEN);
+  written += TRUNNEL_REND_COOKIE_LEN; ptr += TRUNNEL_REND_COOKIE_LEN;
+
+  /* Encode struct cell_extension extensions */
+  trunnel_assert(written <= avail);
+  result = cell_extension_encode(ptr, avail - written, obj->extensions);
+  if (result < 0)
+    goto fail; /* XXXXXXX !*/
+  written += result; ptr += result;
+
+  /* Encode u8 onion_key_type */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->onion_key_type));
+  written += 1; ptr += 1;
+
+  /* Encode u16 onion_key_len */
+  trunnel_assert(written <= avail);
+  if (avail - written < 2)
+    goto truncated;
+  trunnel_set_uint16(ptr, trunnel_htons(obj->onion_key_len));
+  written += 2; ptr += 2;
+
+  /* Encode u8 onion_key[onion_key_len] */
+  {
+    size_t elt_len = TRUNNEL_DYNARRAY_LEN(&obj->onion_key);
+    trunnel_assert(obj->onion_key_len == elt_len);
+    trunnel_assert(written <= avail);
+    if (avail - written < elt_len)
+      goto truncated;
+    if (elt_len)
+      memcpy(ptr, obj->onion_key.elts_, elt_len);
+    written += elt_len; ptr += elt_len;
+  }
+
+  /* Encode u8 nspec */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->nspec));
+  written += 1; ptr += 1;
+
+  /* Encode struct link_specifier nspecs[nspec] */
+  {
+
+    unsigned idx;
+    for (idx = 0; idx < TRUNNEL_DYNARRAY_LEN(&obj->nspecs); ++idx) {
+      trunnel_assert(written <= avail);
+      result = link_specifier_encode(ptr, avail - written, TRUNNEL_DYNARRAY_GET(&obj->nspecs, idx));
+      if (result < 0)
+        goto fail; /* XXXXXXX !*/
+      written += result; ptr += result;
+    }
+  }
+
+  /* Encode u8 pad[] */
+  {
+    size_t elt_len = TRUNNEL_DYNARRAY_LEN(&obj->pad);
+    trunnel_assert(written <= avail);
+    if (avail - written < elt_len)
+      goto truncated;
+    if (elt_len)
+      memcpy(ptr, obj->pad.elts_, elt_len);
+    written += elt_len; ptr += elt_len;
+  }
+
+
+  trunnel_assert(ptr == output + written);
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  {
+    trunnel_assert(encoded_len >= 0);
+    trunnel_assert((size_t)encoded_len == written);
+  }
+
+#endif
+
+  return written;
+
+ truncated:
+  result = -2;
+  goto fail;
+ check_failed:
+  (void)msg;
+  result = -1;
+  goto fail;
+ fail:
+  trunnel_assert(result < 0);
+  return result;
+}
+
+/** As hs_cell_introduce_encrypted_parse(), but do not allocate the
+ * output object.
+ */
+static ssize_t
+hs_cell_introduce_encrypted_parse_into(hs_cell_introduce_encrypted_t *obj, const uint8_t *input, const size_t len_in)
+{
+  const uint8_t *ptr = input;
+  size_t remaining = len_in;
+  ssize_t result = 0;
+  (void)result;
+
+  /* Parse u8 rend_cookie[TRUNNEL_REND_COOKIE_LEN] */
+  CHECK_REMAINING(TRUNNEL_REND_COOKIE_LEN, truncated);
+  memcpy(obj->rend_cookie, ptr, TRUNNEL_REND_COOKIE_LEN);
+  remaining -= TRUNNEL_REND_COOKIE_LEN; ptr += TRUNNEL_REND_COOKIE_LEN;
+
+  /* Parse struct cell_extension extensions */
+  result = cell_extension_parse(&obj->extensions, ptr, remaining);
+  if (result < 0)
+    goto relay_fail;
+  trunnel_assert((size_t)result <= remaining);
+  remaining -= result; ptr += result;
+
+  /* Parse u8 onion_key_type */
+  CHECK_REMAINING(1, truncated);
+  obj->onion_key_type = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+
+  /* Parse u16 onion_key_len */
+  CHECK_REMAINING(2, truncated);
+  obj->onion_key_len = trunnel_ntohs(trunnel_get_uint16(ptr));
+  remaining -= 2; ptr += 2;
+
+  /* Parse u8 onion_key[onion_key_len] */
+  CHECK_REMAINING(obj->onion_key_len, truncated);
+  TRUNNEL_DYNARRAY_EXPAND(uint8_t, &obj->onion_key, obj->onion_key_len, {});
+  obj->onion_key.n_ = obj->onion_key_len;
+  if (obj->onion_key_len)
+    memcpy(obj->onion_key.elts_, ptr, obj->onion_key_len);
+  ptr += obj->onion_key_len; remaining -= obj->onion_key_len;
+
+  /* Parse u8 nspec */
+  CHECK_REMAINING(1, truncated);
+  obj->nspec = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+
+  /* Parse struct link_specifier nspecs[nspec] */
+  TRUNNEL_DYNARRAY_EXPAND(link_specifier_t *, &obj->nspecs, obj->nspec, {});
+  {
+    link_specifier_t * elt;
+    unsigned idx;
+    for (idx = 0; idx < obj->nspec; ++idx) {
+      result = link_specifier_parse(&elt, ptr, remaining);
+      if (result < 0)
+        goto relay_fail;
+      trunnel_assert((size_t)result <= remaining);
+      remaining -= result; ptr += result;
+      TRUNNEL_DYNARRAY_ADD(link_specifier_t *, &obj->nspecs, elt, {link_specifier_free(elt);});
+    }
+  }
+
+  /* Parse u8 pad[] */
+  TRUNNEL_DYNARRAY_EXPAND(uint8_t, &obj->pad, remaining, {});
+  obj->pad.n_ = remaining;
+  if (remaining)
+    memcpy(obj->pad.elts_, ptr, remaining);
+  ptr += remaining; remaining -= remaining;
+  trunnel_assert(ptr + remaining == input + len_in);
+  return len_in - remaining;
+
+ truncated:
+  return -2;
+ relay_fail:
+  trunnel_assert(result < 0);
+  return result;
+ trunnel_alloc_failed:
+  return -1;
+}
+
+ssize_t
+hs_cell_introduce_encrypted_parse(hs_cell_introduce_encrypted_t **output, const uint8_t *input, const size_t len_in)
+{
+  ssize_t result;
+  *output = hs_cell_introduce_encrypted_new();
+  if (NULL == *output)
+    return -1;
+  result = hs_cell_introduce_encrypted_parse_into(*output, input, len_in);
+  if (result < 0) {
+    hs_cell_introduce_encrypted_free(*output);
+    *output = NULL;
+  }
+  return result;
+}

src/trunnel/hs/cell_introduce1.trunnel

+/*
+ * 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[];
+};

src/trunnel/include.am

@@ -19,7 +19,8 @@ TRUNNELSOURCES = \
 	src/trunnel/link_handshake.c \
 	src/trunnel/pwbox.c			\
 	src/trunnel/hs/cell_common.c            \
-	src/trunnel/hs/cell_establish_intro.c
+	src/trunnel/hs/cell_establish_intro.c	\
+	src/trunnel/hs/cell_introduce1.c
 
 TRUNNELHEADERS = \
 	src/ext/trunnel/trunnel.h		\
@@ -29,7 +30,8 @@ TRUNNELHEADERS = \
 	src/trunnel/link_handshake.h		\
 	src/trunnel/pwbox.h			\
 	src/trunnel/hs/cell_common.h            \
-	src/trunnel/hs/cell_establish_intro.h
+	src/trunnel/hs/cell_establish_intro.h	\
+	src/trunnel/hs/cell_introduce1.h
 
 src_trunnel_libor_trunnel_a_SOURCES = $(TRUNNELSOURCES)
 src_trunnel_libor_trunnel_a_CPPFLAGS = -DTRUNNEL_LOCAL_H $(AM_CPPFLAGS)