commit e4856d1bbf1e3d0dd452a7a1b495464404007577 Author: David Goulet dgoulet@torproject.org Date: Tue Jun 25 09:40:56 2019 -0400
trunnel: Add prop305 ESTABLISH_INTRO DoS cell extension
Signed-off-by: David Goulet dgoulet@torproject.org --- src/trunnel/hs/cell_establish_intro.c | 469 ++++++++++++++++++++++++++++ src/trunnel/hs/cell_establish_intro.h | 157 ++++++++++ src/trunnel/hs/cell_establish_intro.trunnel | 19 ++ 3 files changed, 645 insertions(+)
diff --git a/src/trunnel/hs/cell_establish_intro.c b/src/trunnel/hs/cell_establish_intro.c index 99ceadbda..f31404c55 100644 --- a/src/trunnel/hs/cell_establish_intro.c +++ b/src/trunnel/hs/cell_establish_intro.c @@ -36,6 +36,185 @@ ssize_t trn_cell_extension_encoded_len(const trn_cell_extension_t *obj); ssize_t trn_cell_extension_encode(uint8_t *output, size_t avail, const trn_cell_extension_t *input); const char *trn_cell_extension_check(const trn_cell_extension_t *obj); int trn_cell_extension_clear_errors(trn_cell_extension_t *obj); +trn_cell_extension_dos_param_t * +trn_cell_extension_dos_param_new(void) +{ + trn_cell_extension_dos_param_t *val = trunnel_calloc(1, sizeof(trn_cell_extension_dos_param_t)); + if (NULL == val) + return NULL; + return val; +} + +/** Release all storage held inside 'obj', but do not free 'obj'. + */ +static void +trn_cell_extension_dos_param_clear(trn_cell_extension_dos_param_t *obj) +{ + (void) obj; +} + +void +trn_cell_extension_dos_param_free(trn_cell_extension_dos_param_t *obj) +{ + if (obj == NULL) + return; + trn_cell_extension_dos_param_clear(obj); + trunnel_memwipe(obj, sizeof(trn_cell_extension_dos_param_t)); + trunnel_free_(obj); +} + +uint8_t +trn_cell_extension_dos_param_get_type(const trn_cell_extension_dos_param_t *inp) +{ + return inp->type; +} +int +trn_cell_extension_dos_param_set_type(trn_cell_extension_dos_param_t *inp, uint8_t val) +{ + inp->type = val; + return 0; +} +uint64_t +trn_cell_extension_dos_param_get_value(const trn_cell_extension_dos_param_t *inp) +{ + return inp->value; +} +int +trn_cell_extension_dos_param_set_value(trn_cell_extension_dos_param_t *inp, uint64_t val) +{ + inp->value = val; + return 0; +} +const char * +trn_cell_extension_dos_param_check(const trn_cell_extension_dos_param_t *obj) +{ + if (obj == NULL) + return "Object was NULL"; + if (obj->trunnel_error_code_) + return "A set function failed on this object"; + return NULL; +} + +ssize_t +trn_cell_extension_dos_param_encoded_len(const trn_cell_extension_dos_param_t *obj) +{ + ssize_t result = 0; + + if (NULL != trn_cell_extension_dos_param_check(obj)) + return -1; + + + /* Length of u8 type */ + result += 1; + + /* Length of u64 value */ + result += 8; + return result; +} +int +trn_cell_extension_dos_param_clear_errors(trn_cell_extension_dos_param_t *obj) +{ + int r = obj->trunnel_error_code_; + obj->trunnel_error_code_ = 0; + return r; +} +ssize_t +trn_cell_extension_dos_param_encode(uint8_t *output, const size_t avail, const trn_cell_extension_dos_param_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 = trn_cell_extension_dos_param_encoded_len(obj); +#endif + + if (NULL != (msg = trn_cell_extension_dos_param_check(obj))) + goto check_failed; + +#ifdef TRUNNEL_CHECK_ENCODED_LEN + trunnel_assert(encoded_len >= 0); +#endif + + /* Encode u8 type */ + trunnel_assert(written <= avail); + if (avail - written < 1) + goto truncated; + trunnel_set_uint8(ptr, (obj->type)); + written += 1; ptr += 1; + + /* Encode u64 value */ + trunnel_assert(written <= avail); + if (avail - written < 8) + goto truncated; + trunnel_set_uint64(ptr, trunnel_htonll(obj->value)); + written += 8; ptr += 8; + + + 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 trn_cell_extension_dos_param_parse(), but do not allocate the + * output object. + */ +static ssize_t +trn_cell_extension_dos_param_parse_into(trn_cell_extension_dos_param_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 type */ + CHECK_REMAINING(1, truncated); + obj->type = (trunnel_get_uint8(ptr)); + remaining -= 1; ptr += 1; + + /* Parse u64 value */ + CHECK_REMAINING(8, truncated); + obj->value = trunnel_ntohll(trunnel_get_uint64(ptr)); + remaining -= 8; ptr += 8; + trunnel_assert(ptr + remaining == input + len_in); + return len_in - remaining; + + truncated: + return -2; +} + +ssize_t +trn_cell_extension_dos_param_parse(trn_cell_extension_dos_param_t **output, const uint8_t *input, const size_t len_in) +{ + ssize_t result; + *output = trn_cell_extension_dos_param_new(); + if (NULL == *output) + return -1; + result = trn_cell_extension_dos_param_parse_into(*output, input, len_in); + if (result < 0) { + trn_cell_extension_dos_param_free(*output); + *output = NULL; + } + return result; +} trn_cell_establish_intro_t * trn_cell_establish_intro_new(void) { @@ -561,6 +740,296 @@ trn_cell_establish_intro_parse(trn_cell_establish_intro_t **output, const uint8_ } return result; } +trn_cell_extension_dos_t * +trn_cell_extension_dos_new(void) +{ + trn_cell_extension_dos_t *val = trunnel_calloc(1, sizeof(trn_cell_extension_dos_t)); + if (NULL == val) + return NULL; + return val; +} + +/** Release all storage held inside 'obj', but do not free 'obj'. + */ +static void +trn_cell_extension_dos_clear(trn_cell_extension_dos_t *obj) +{ + (void) obj; + { + + unsigned idx; + for (idx = 0; idx < TRUNNEL_DYNARRAY_LEN(&obj->params); ++idx) { + trn_cell_extension_dos_param_free(TRUNNEL_DYNARRAY_GET(&obj->params, idx)); + } + } + TRUNNEL_DYNARRAY_WIPE(&obj->params); + TRUNNEL_DYNARRAY_CLEAR(&obj->params); +} + +void +trn_cell_extension_dos_free(trn_cell_extension_dos_t *obj) +{ + if (obj == NULL) + return; + trn_cell_extension_dos_clear(obj); + trunnel_memwipe(obj, sizeof(trn_cell_extension_dos_t)); + trunnel_free_(obj); +} + +uint8_t +trn_cell_extension_dos_get_n_params(const trn_cell_extension_dos_t *inp) +{ + return inp->n_params; +} +int +trn_cell_extension_dos_set_n_params(trn_cell_extension_dos_t *inp, uint8_t val) +{ + inp->n_params = val; + return 0; +} +size_t +trn_cell_extension_dos_getlen_params(const trn_cell_extension_dos_t *inp) +{ + return TRUNNEL_DYNARRAY_LEN(&inp->params); +} + +struct trn_cell_extension_dos_param_st * +trn_cell_extension_dos_get_params(trn_cell_extension_dos_t *inp, size_t idx) +{ + return TRUNNEL_DYNARRAY_GET(&inp->params, idx); +} + + const struct trn_cell_extension_dos_param_st * +trn_cell_extension_dos_getconst_params(const trn_cell_extension_dos_t *inp, size_t idx) +{ + return trn_cell_extension_dos_get_params((trn_cell_extension_dos_t*)inp, idx); +} +int +trn_cell_extension_dos_set_params(trn_cell_extension_dos_t *inp, size_t idx, struct trn_cell_extension_dos_param_st * elt) +{ + trn_cell_extension_dos_param_t *oldval = TRUNNEL_DYNARRAY_GET(&inp->params, idx); + if (oldval && oldval != elt) + trn_cell_extension_dos_param_free(oldval); + return trn_cell_extension_dos_set0_params(inp, idx, elt); +} +int +trn_cell_extension_dos_set0_params(trn_cell_extension_dos_t *inp, size_t idx, struct trn_cell_extension_dos_param_st * elt) +{ + TRUNNEL_DYNARRAY_SET(&inp->params, idx, elt); + return 0; +} +int +trn_cell_extension_dos_add_params(trn_cell_extension_dos_t *inp, struct trn_cell_extension_dos_param_st * elt) +{ +#if SIZE_MAX >= UINT8_MAX + if (inp->params.n_ == UINT8_MAX) + goto trunnel_alloc_failed; +#endif + TRUNNEL_DYNARRAY_ADD(struct trn_cell_extension_dos_param_st *, &inp->params, elt, {}); + return 0; + trunnel_alloc_failed: + TRUNNEL_SET_ERROR_CODE(inp); + return -1; +} + +struct trn_cell_extension_dos_param_st * * +trn_cell_extension_dos_getarray_params(trn_cell_extension_dos_t *inp) +{ + return inp->params.elts_; +} +const struct trn_cell_extension_dos_param_st * const * +trn_cell_extension_dos_getconstarray_params(const trn_cell_extension_dos_t *inp) +{ + return (const struct trn_cell_extension_dos_param_st * const *)trn_cell_extension_dos_getarray_params((trn_cell_extension_dos_t*)inp); +} +int +trn_cell_extension_dos_setlen_params(trn_cell_extension_dos_t *inp, size_t newlen) +{ + struct trn_cell_extension_dos_param_st * *newptr; +#if UINT8_MAX < SIZE_MAX + if (newlen > UINT8_MAX) + goto trunnel_alloc_failed; +#endif + newptr = trunnel_dynarray_setlen(&inp->params.allocated_, + &inp->params.n_, inp->params.elts_, newlen, + sizeof(inp->params.elts_[0]), (trunnel_free_fn_t) trn_cell_extension_dos_param_free, + &inp->trunnel_error_code_); + if (newlen != 0 && newptr == NULL) + goto trunnel_alloc_failed; + inp->params.elts_ = newptr; + return 0; + trunnel_alloc_failed: + TRUNNEL_SET_ERROR_CODE(inp); + return -1; +} +const char * +trn_cell_extension_dos_check(const trn_cell_extension_dos_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; + + unsigned idx; + for (idx = 0; idx < TRUNNEL_DYNARRAY_LEN(&obj->params); ++idx) { + if (NULL != (msg = trn_cell_extension_dos_param_check(TRUNNEL_DYNARRAY_GET(&obj->params, idx)))) + return msg; + } + } + if (TRUNNEL_DYNARRAY_LEN(&obj->params) != obj->n_params) + return "Length mismatch for params"; + return NULL; +} + +ssize_t +trn_cell_extension_dos_encoded_len(const trn_cell_extension_dos_t *obj) +{ + ssize_t result = 0; + + if (NULL != trn_cell_extension_dos_check(obj)) + return -1; + + + /* Length of u8 n_params */ + result += 1; + + /* Length of struct trn_cell_extension_dos_param params[n_params] */ + { + + unsigned idx; + for (idx = 0; idx < TRUNNEL_DYNARRAY_LEN(&obj->params); ++idx) { + result += trn_cell_extension_dos_param_encoded_len(TRUNNEL_DYNARRAY_GET(&obj->params, idx)); + } + } + return result; +} +int +trn_cell_extension_dos_clear_errors(trn_cell_extension_dos_t *obj) +{ + int r = obj->trunnel_error_code_; + obj->trunnel_error_code_ = 0; + return r; +} +ssize_t +trn_cell_extension_dos_encode(uint8_t *output, const size_t avail, const trn_cell_extension_dos_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 = trn_cell_extension_dos_encoded_len(obj); +#endif + + if (NULL != (msg = trn_cell_extension_dos_check(obj))) + goto check_failed; + +#ifdef TRUNNEL_CHECK_ENCODED_LEN + trunnel_assert(encoded_len >= 0); +#endif + + /* Encode u8 n_params */ + trunnel_assert(written <= avail); + if (avail - written < 1) + goto truncated; + trunnel_set_uint8(ptr, (obj->n_params)); + written += 1; ptr += 1; + + /* Encode struct trn_cell_extension_dos_param params[n_params] */ + { + + unsigned idx; + for (idx = 0; idx < TRUNNEL_DYNARRAY_LEN(&obj->params); ++idx) { + trunnel_assert(written <= avail); + result = trn_cell_extension_dos_param_encode(ptr, avail - written, TRUNNEL_DYNARRAY_GET(&obj->params, idx)); + 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 trn_cell_extension_dos_parse(), but do not allocate the output + * object. + */ +static ssize_t +trn_cell_extension_dos_parse_into(trn_cell_extension_dos_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 n_params */ + CHECK_REMAINING(1, truncated); + obj->n_params = (trunnel_get_uint8(ptr)); + remaining -= 1; ptr += 1; + + /* Parse struct trn_cell_extension_dos_param params[n_params] */ + TRUNNEL_DYNARRAY_EXPAND(trn_cell_extension_dos_param_t *, &obj->params, obj->n_params, {}); + { + trn_cell_extension_dos_param_t * elt; + unsigned idx; + for (idx = 0; idx < obj->n_params; ++idx) { + result = trn_cell_extension_dos_param_parse(&elt, ptr, remaining); + if (result < 0) + goto relay_fail; + trunnel_assert((size_t)result <= remaining); + remaining -= result; ptr += result; + TRUNNEL_DYNARRAY_ADD(trn_cell_extension_dos_param_t *, &obj->params, elt, {trn_cell_extension_dos_param_free(elt);}); + } + } + 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 +trn_cell_extension_dos_parse(trn_cell_extension_dos_t **output, const uint8_t *input, const size_t len_in) +{ + ssize_t result; + *output = trn_cell_extension_dos_new(); + if (NULL == *output) + return -1; + result = trn_cell_extension_dos_parse_into(*output, input, len_in); + if (result < 0) { + trn_cell_extension_dos_free(*output); + *output = NULL; + } + return result; +} trn_cell_intro_established_t * trn_cell_intro_established_new(void) { diff --git a/src/trunnel/hs/cell_establish_intro.h b/src/trunnel/hs/cell_establish_intro.h index 1908645aa..cc3797fc9 100644 --- a/src/trunnel/hs/cell_establish_intro.h +++ b/src/trunnel/hs/cell_establish_intro.h @@ -10,6 +10,15 @@
struct trn_cell_extension_st; #define TRUNNEL_SHA3_256_LEN 32 +#define TRUNNEL_CELL_EXTENSION_TYPE_DOS 1 +#if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_TRN_CELL_EXTENSION_DOS_PARAM) +struct trn_cell_extension_dos_param_st { + uint8_t type; + uint64_t value; + uint8_t trunnel_error_code_; +}; +#endif +typedef struct trn_cell_extension_dos_param_st trn_cell_extension_dos_param_t; #if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_TRN_CELL_ESTABLISH_INTRO) struct trn_cell_establish_intro_st { const uint8_t *start_cell; @@ -26,6 +35,14 @@ struct trn_cell_establish_intro_st { }; #endif typedef struct trn_cell_establish_intro_st trn_cell_establish_intro_t; +#if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_TRN_CELL_EXTENSION_DOS) +struct trn_cell_extension_dos_st { + uint8_t n_params; + TRUNNEL_DYNARRAY_HEAD(, struct trn_cell_extension_dos_param_st *) params; + uint8_t trunnel_error_code_; +}; +#endif +typedef struct trn_cell_extension_dos_st trn_cell_extension_dos_t; #if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_TRN_CELL_INTRO_ESTABLISHED) struct trn_cell_intro_established_st { struct trn_cell_extension_st *extensions; @@ -33,6 +50,62 @@ struct trn_cell_intro_established_st { }; #endif typedef struct trn_cell_intro_established_st trn_cell_intro_established_t; +/** Return a newly allocated trn_cell_extension_dos_param with all + * elements set to zero. + */ +trn_cell_extension_dos_param_t *trn_cell_extension_dos_param_new(void); +/** Release all storage held by the trn_cell_extension_dos_param in + * 'victim'. (Do nothing if 'victim' is NULL.) + */ +void trn_cell_extension_dos_param_free(trn_cell_extension_dos_param_t *victim); +/** Try to parse a trn_cell_extension_dos_param from the buffer in + * 'input', using up to 'len_in' bytes from the input buffer. On + * success, return the number of bytes consumed and set *output to the + * newly allocated trn_cell_extension_dos_param_t. On failure, return + * -2 if the input appears truncated, and -1 if the input is otherwise + * invalid. + */ +ssize_t trn_cell_extension_dos_param_parse(trn_cell_extension_dos_param_t **output, const uint8_t *input, const size_t len_in); +/** Return the number of bytes we expect to need to encode the + * trn_cell_extension_dos_param in 'obj'. On failure, return a + * negative value. Note that this value may be an overestimate, and + * can even be an underestimate for certain unencodeable objects. + */ +ssize_t trn_cell_extension_dos_param_encoded_len(const trn_cell_extension_dos_param_t *obj); +/** Try to encode the trn_cell_extension_dos_param from 'input' into + * the buffer at 'output', using up to 'avail' bytes of the output + * buffer. On success, return the number of bytes used. On failure, + * return -2 if the buffer was not long enough, and -1 if the input + * was invalid. + */ +ssize_t trn_cell_extension_dos_param_encode(uint8_t *output, size_t avail, const trn_cell_extension_dos_param_t *input); +/** Check whether the internal state of the + * trn_cell_extension_dos_param in 'obj' is consistent. Return NULL if + * it is, and a short message if it is not. + */ +const char *trn_cell_extension_dos_param_check(const trn_cell_extension_dos_param_t *obj); +/** Clear any errors that were set on the object 'obj' by its setter + * functions. Return true iff errors were cleared. + */ +int trn_cell_extension_dos_param_clear_errors(trn_cell_extension_dos_param_t *obj); +/** Return the value of the type field of the + * trn_cell_extension_dos_param_t in 'inp' + */ +uint8_t trn_cell_extension_dos_param_get_type(const trn_cell_extension_dos_param_t *inp); +/** Set the value of the type field of the + * trn_cell_extension_dos_param_t in 'inp' to 'val'. Return 0 on + * success; return -1 and set the error code on 'inp' on failure. + */ +int trn_cell_extension_dos_param_set_type(trn_cell_extension_dos_param_t *inp, uint8_t val); +/** Return the value of the value field of the + * trn_cell_extension_dos_param_t in 'inp' + */ +uint64_t trn_cell_extension_dos_param_get_value(const trn_cell_extension_dos_param_t *inp); +/** Set the value of the value field of the + * trn_cell_extension_dos_param_t in 'inp' to 'val'. Return 0 on + * success; return -1 and set the error code on 'inp' on failure. + */ +int trn_cell_extension_dos_param_set_value(trn_cell_extension_dos_param_t *inp, uint64_t val); /** Return a newly allocated trn_cell_establish_intro with all * elements set to zero. */ @@ -216,6 +289,90 @@ const uint8_t * trn_cell_establish_intro_getconstarray_sig(const trn_cell_estab * -1 and set the error code on 'inp' on failure. */ int trn_cell_establish_intro_setlen_sig(trn_cell_establish_intro_t *inp, size_t newlen); +/** Return a newly allocated trn_cell_extension_dos with all elements + * set to zero. + */ +trn_cell_extension_dos_t *trn_cell_extension_dos_new(void); +/** Release all storage held by the trn_cell_extension_dos in + * 'victim'. (Do nothing if 'victim' is NULL.) + */ +void trn_cell_extension_dos_free(trn_cell_extension_dos_t *victim); +/** Try to parse a trn_cell_extension_dos from the buffer in 'input', + * using up to 'len_in' bytes from the input buffer. On success, + * return the number of bytes consumed and set *output to the newly + * allocated trn_cell_extension_dos_t. On failure, return -2 if the + * input appears truncated, and -1 if the input is otherwise invalid. + */ +ssize_t trn_cell_extension_dos_parse(trn_cell_extension_dos_t **output, const uint8_t *input, const size_t len_in); +/** Return the number of bytes we expect to need to encode the + * trn_cell_extension_dos in 'obj'. On failure, return a negative + * value. Note that this value may be an overestimate, and can even be + * an underestimate for certain unencodeable objects. + */ +ssize_t trn_cell_extension_dos_encoded_len(const trn_cell_extension_dos_t *obj); +/** Try to encode the trn_cell_extension_dos from 'input' into the + * buffer at 'output', using up to 'avail' bytes of the output buffer. + * On success, return the number of bytes used. On failure, return -2 + * if the buffer was not long enough, and -1 if the input was invalid. + */ +ssize_t trn_cell_extension_dos_encode(uint8_t *output, size_t avail, const trn_cell_extension_dos_t *input); +/** Check whether the internal state of the trn_cell_extension_dos in + * 'obj' is consistent. Return NULL if it is, and a short message if + * it is not. + */ +const char *trn_cell_extension_dos_check(const trn_cell_extension_dos_t *obj); +/** Clear any errors that were set on the object 'obj' by its setter + * functions. Return true iff errors were cleared. + */ +int trn_cell_extension_dos_clear_errors(trn_cell_extension_dos_t *obj); +/** Return the value of the n_params field of the + * trn_cell_extension_dos_t in 'inp' + */ +uint8_t trn_cell_extension_dos_get_n_params(const trn_cell_extension_dos_t *inp); +/** Set the value of the n_params field of the + * trn_cell_extension_dos_t in 'inp' to 'val'. Return 0 on success; + * return -1 and set the error code on 'inp' on failure. + */ +int trn_cell_extension_dos_set_n_params(trn_cell_extension_dos_t *inp, uint8_t val); +/** Return the length of the dynamic array holding the params field of + * the trn_cell_extension_dos_t in 'inp'. + */ +size_t trn_cell_extension_dos_getlen_params(const trn_cell_extension_dos_t *inp); +/** Return the element at position 'idx' of the dynamic array field + * params of the trn_cell_extension_dos_t in 'inp'. + */ +struct trn_cell_extension_dos_param_st * trn_cell_extension_dos_get_params(trn_cell_extension_dos_t *inp, size_t idx); +/** As trn_cell_extension_dos_get_params, but take and return a const + * pointer + */ + const struct trn_cell_extension_dos_param_st * trn_cell_extension_dos_getconst_params(const trn_cell_extension_dos_t *inp, size_t idx); +/** Change the element at position 'idx' of the dynamic array field + * params of the trn_cell_extension_dos_t in 'inp', so that it will + * hold the value 'elt'. Free the previous value, if any. + */ +int trn_cell_extension_dos_set_params(trn_cell_extension_dos_t *inp, size_t idx, struct trn_cell_extension_dos_param_st * elt); +/** As trn_cell_extension_dos_set_params, but does not free the + * previous value. + */ +int trn_cell_extension_dos_set0_params(trn_cell_extension_dos_t *inp, size_t idx, struct trn_cell_extension_dos_param_st * elt); +/** Append a new element 'elt' to the dynamic array field params of + * the trn_cell_extension_dos_t in 'inp'. + */ +int trn_cell_extension_dos_add_params(trn_cell_extension_dos_t *inp, struct trn_cell_extension_dos_param_st * elt); +/** Return a pointer to the variable-length array field params of + * 'inp'. + */ +struct trn_cell_extension_dos_param_st * * trn_cell_extension_dos_getarray_params(trn_cell_extension_dos_t *inp); +/** As trn_cell_extension_dos_get_params, but take and return a const + * pointer + */ +const struct trn_cell_extension_dos_param_st * const * trn_cell_extension_dos_getconstarray_params(const trn_cell_extension_dos_t *inp); +/** Change the length of the variable-length array field params of + * 'inp' to 'newlen'.Fill extra elements with NULL; free removed + * elements. Return 0 on success; return -1 and set the error code on + * 'inp' on failure. + */ +int trn_cell_extension_dos_setlen_params(trn_cell_extension_dos_t *inp, size_t newlen); /** Return a newly allocated trn_cell_intro_established with all * elements set to zero. */ diff --git a/src/trunnel/hs/cell_establish_intro.trunnel b/src/trunnel/hs/cell_establish_intro.trunnel index 011ee62a1..08a110953 100644 --- a/src/trunnel/hs/cell_establish_intro.trunnel +++ b/src/trunnel/hs/cell_establish_intro.trunnel @@ -39,3 +39,22 @@ struct trn_cell_intro_established { /* Extension(s). Reserved fields. */ struct trn_cell_extension extensions; }; + +/* + * ESTABLISH_INTRO cell extensions. + */ + +const TRUNNEL_CELL_EXTENSION_TYPE_DOS = 0x01; + +/* + * DoS Parameters Extension. See proposal 305 for more details. + */ +struct trn_cell_extension_dos_param { + u8 type; + u64 value; +}; + +struct trn_cell_extension_dos { + u8 n_params; + struct trn_cell_extension_dos_param params[n_params]; +};