commit 2f1b3d647ff1489f4cb0f25d96701eaf35e076da Author: David Goulet dgoulet@torproject.org Date: Sun Jul 23 15:04:59 2017 -0400

trunnel: Add RENDEZVOUS2 cell definition

Signed-off-by: David Goulet dgoulet@torproject.org --- src/trunnel/hs/cell_rendezvous.c | 178 +++++++++++++++++++++++++++++++++ src/trunnel/hs/cell_rendezvous.h | 69 +++++++++++++ src/trunnel/hs/cell_rendezvous.trunnel | 13 ++- 3 files changed, 259 insertions(+), 1 deletion(-)

diff --git a/src/trunnel/hs/cell_rendezvous.c b/src/trunnel/hs/cell_rendezvous.c index e961cd09d..e4d3244bd 100644 --- a/src/trunnel/hs/cell_rendezvous.c +++ b/src/trunnel/hs/cell_rendezvous.c @@ -290,3 +290,181 @@ trn_cell_rendezvous1_parse(trn_cell_rendezvous1_t **output, const uint8_t *input } return result; } +trn_cell_rendezvous2_t * +trn_cell_rendezvous2_new(void) +{ + trn_cell_rendezvous2_t *val = trunnel_calloc(1, sizeof(trn_cell_rendezvous2_t)); + if (NULL == val) + return NULL; + return val; +} + +/** Release all storage held inside 'obj', but do not free 'obj'. + */ +static void +trn_cell_rendezvous2_clear(trn_cell_rendezvous2_t *obj) +{ + (void) obj; +} + +void +trn_cell_rendezvous2_free(trn_cell_rendezvous2_t *obj) +{ + if (obj == NULL) + return; + trn_cell_rendezvous2_clear(obj); + trunnel_memwipe(obj, sizeof(trn_cell_rendezvous2_t)); + trunnel_free_(obj); +} + +size_t +trn_cell_rendezvous2_getlen_handshake_info(const trn_cell_rendezvous2_t *inp) +{ + (void)inp; return TRUNNEL_HANDSHAKE_INFO_LEN; +} + +uint8_t +trn_cell_rendezvous2_get_handshake_info(trn_cell_rendezvous2_t *inp, size_t idx) +{ + trunnel_assert(idx < TRUNNEL_HANDSHAKE_INFO_LEN); + return inp->handshake_info[idx]; +} + +uint8_t +trn_cell_rendezvous2_getconst_handshake_info(const trn_cell_rendezvous2_t *inp, size_t idx) +{ + return trn_cell_rendezvous2_get_handshake_info((trn_cell_rendezvous2_t*)inp, idx); +} +int +trn_cell_rendezvous2_set_handshake_info(trn_cell_rendezvous2_t *inp, size_t idx, uint8_t elt) +{ + trunnel_assert(idx < TRUNNEL_HANDSHAKE_INFO_LEN); + inp->handshake_info[idx] = elt; + return 0; +} + +uint8_t * +trn_cell_rendezvous2_getarray_handshake_info(trn_cell_rendezvous2_t *inp) +{ + return inp->handshake_info; +} +const uint8_t * +trn_cell_rendezvous2_getconstarray_handshake_info(const trn_cell_rendezvous2_t *inp) +{ + return (const uint8_t *)trn_cell_rendezvous2_getarray_handshake_info((trn_cell_rendezvous2_t*)inp); +} +const char * +trn_cell_rendezvous2_check(const trn_cell_rendezvous2_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_rendezvous2_encoded_len(const trn_cell_rendezvous2_t *obj) +{ + ssize_t result = 0; + + if (NULL != trn_cell_rendezvous2_check(obj)) + return -1; + + + /* Length of u8 handshake_info[TRUNNEL_HANDSHAKE_INFO_LEN] */ + result += TRUNNEL_HANDSHAKE_INFO_LEN; + return result; +} +int +trn_cell_rendezvous2_clear_errors(trn_cell_rendezvous2_t *obj) +{ + int r = obj->trunnel_error_code_; + obj->trunnel_error_code_ = 0; + return r; +} +ssize_t +trn_cell_rendezvous2_encode(uint8_t *output, const size_t avail, const trn_cell_rendezvous2_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_rendezvous2_encoded_len(obj); +#endif + + if (NULL != (msg = trn_cell_rendezvous2_check(obj))) + goto check_failed; + +#ifdef TRUNNEL_CHECK_ENCODED_LEN + trunnel_assert(encoded_len >= 0); +#endif + + /* Encode u8 handshake_info[TRUNNEL_HANDSHAKE_INFO_LEN] */ + trunnel_assert(written <= avail); + if (avail - written < TRUNNEL_HANDSHAKE_INFO_LEN) + goto truncated; + memcpy(ptr, obj->handshake_info, TRUNNEL_HANDSHAKE_INFO_LEN); + written += TRUNNEL_HANDSHAKE_INFO_LEN; ptr += TRUNNEL_HANDSHAKE_INFO_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 trn_cell_rendezvous2_parse(), but do not allocate the output + * object. + */ +static ssize_t +trn_cell_rendezvous2_parse_into(trn_cell_rendezvous2_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 handshake_info[TRUNNEL_HANDSHAKE_INFO_LEN] */ + CHECK_REMAINING(TRUNNEL_HANDSHAKE_INFO_LEN, truncated); + memcpy(obj->handshake_info, ptr, TRUNNEL_HANDSHAKE_INFO_LEN); + remaining -= TRUNNEL_HANDSHAKE_INFO_LEN; ptr += TRUNNEL_HANDSHAKE_INFO_LEN; + trunnel_assert(ptr + remaining == input + len_in); + return len_in - remaining; + + truncated: + return -2; +} + +ssize_t +trn_cell_rendezvous2_parse(trn_cell_rendezvous2_t **output, const uint8_t *input, const size_t len_in) +{ + ssize_t result; + *output = trn_cell_rendezvous2_new(); + if (NULL == *output) + return -1; + result = trn_cell_rendezvous2_parse_into(*output, input, len_in); + if (result < 0) { + trn_cell_rendezvous2_free(*output); + *output = NULL; + } + return result; +} diff --git a/src/trunnel/hs/cell_rendezvous.h b/src/trunnel/hs/cell_rendezvous.h index 2387d77f4..5dcc6539b 100644 --- a/src/trunnel/hs/cell_rendezvous.h +++ b/src/trunnel/hs/cell_rendezvous.h @@ -9,6 +9,7 @@ #include "trunnel.h"

#define TRUNNEL_REND_COOKIE_LEN 20 +#define TRUNNEL_HANDSHAKE_INFO_LEN 64 #if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_TRN_CELL_RENDEZVOUS1) struct trn_cell_rendezvous1_st { uint8_t rendezvous_cookie[TRUNNEL_REND_COOKIE_LEN]; @@ -17,6 +18,13 @@ struct trn_cell_rendezvous1_st { }; #endif typedef struct trn_cell_rendezvous1_st trn_cell_rendezvous1_t; +#if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_TRN_CELL_RENDEZVOUS2) +struct trn_cell_rendezvous2_st { + uint8_t handshake_info[TRUNNEL_HANDSHAKE_INFO_LEN]; + uint8_t trunnel_error_code_; +}; +#endif +typedef struct trn_cell_rendezvous2_st trn_cell_rendezvous2_t; /** Return a newly allocated trn_cell_rendezvous1 with all elements * set to zero. */ @@ -113,6 +121,67 @@ const uint8_t * trn_cell_rendezvous1_getconstarray_handshake_info(const trn_cel * failure. */ int trn_cell_rendezvous1_setlen_handshake_info(trn_cell_rendezvous1_t *inp, size_t newlen); +/** Return a newly allocated trn_cell_rendezvous2 with all elements + * set to zero. + */ +trn_cell_rendezvous2_t *trn_cell_rendezvous2_new(void); +/** Release all storage held by the trn_cell_rendezvous2 in 'victim'. + * (Do nothing if 'victim' is NULL.) + */ +void trn_cell_rendezvous2_free(trn_cell_rendezvous2_t *victim); +/** Try to parse a trn_cell_rendezvous2 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_rendezvous2_t. On failure, return -2 if the + * input appears truncated, and -1 if the input is otherwise invalid. + */ +ssize_t trn_cell_rendezvous2_parse(trn_cell_rendezvous2_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_rendezvous2 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_rendezvous2_encoded_len(const trn_cell_rendezvous2_t *obj); +/** Try to encode the trn_cell_rendezvous2 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_rendezvous2_encode(uint8_t *output, size_t avail, const trn_cell_rendezvous2_t *input); +/** Check whether the internal state of the trn_cell_rendezvous2 in + * 'obj' is consistent. Return NULL if it is, and a short message if + * it is not. + */ +const char *trn_cell_rendezvous2_check(const trn_cell_rendezvous2_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_rendezvous2_clear_errors(trn_cell_rendezvous2_t *obj); +/** Return the (constant) length of the array holding the + * handshake_info field of the trn_cell_rendezvous2_t in 'inp'. + */ +size_t trn_cell_rendezvous2_getlen_handshake_info(const trn_cell_rendezvous2_t *inp); +/** Return the element at position 'idx' of the fixed array field + * handshake_info of the trn_cell_rendezvous2_t in 'inp'. + */ +uint8_t trn_cell_rendezvous2_get_handshake_info(trn_cell_rendezvous2_t *inp, size_t idx); +/** As trn_cell_rendezvous2_get_handshake_info, but take and return a + * const pointer + */ +uint8_t trn_cell_rendezvous2_getconst_handshake_info(const trn_cell_rendezvous2_t *inp, size_t idx); +/** Change the element at position 'idx' of the fixed array field + * handshake_info of the trn_cell_rendezvous2_t in 'inp', so that it + * will hold the value 'elt'. + */ +int trn_cell_rendezvous2_set_handshake_info(trn_cell_rendezvous2_t *inp, size_t idx, uint8_t elt); +/** Return a pointer to the TRUNNEL_HANDSHAKE_INFO_LEN-element array + * field handshake_info of 'inp'. + */ +uint8_t * trn_cell_rendezvous2_getarray_handshake_info(trn_cell_rendezvous2_t *inp); +/** As trn_cell_rendezvous2_get_handshake_info, but take and return a + * const pointer + */ +const uint8_t * trn_cell_rendezvous2_getconstarray_handshake_info(const trn_cell_rendezvous2_t *inp);

#endif diff --git a/src/trunnel/hs/cell_rendezvous.trunnel b/src/trunnel/hs/cell_rendezvous.trunnel index 27f1728b4..2128b4d12 100644 --- a/src/trunnel/hs/cell_rendezvous.trunnel +++ b/src/trunnel/hs/cell_rendezvous.trunnel @@ -1,11 +1,16 @@ /* - * This contains the definition of the RENDEZVOUS1 cell for onion service + * This contains the definition of the RENDEZVOUS1/2 cell for onion service * version 3 and onward. The following format is specified in proposal 224 * section 4.2. */

/* Rendezvous cookie length. */ const TRUNNEL_REND_COOKIE_LEN = 20; +/* The HANDSHAKE_INFO field layout is as follow: + * SERVER_PK [PK_PUBKEY_LEN bytes] + * AUTH [MAC_LEN bytes] + * This means, the size is 32 bytes + 32 bytes. */ +const TRUNNEL_HANDSHAKE_INFO_LEN = 64;

/* RENDEZVOUS1 payload. See details in section 4.2. */ struct trn_cell_rendezvous1 { @@ -16,3 +21,9 @@ struct trn_cell_rendezvous1 { * handshake type used. */ u8 handshake_info[]; }; + +/* RENDEZVOUS2 payload. See details in section 4.2. */ +struct trn_cell_rendezvous2 { + /* The HANDSHAKE_INFO field. */ + u8 handshake_info[TRUNNEL_HANDSHAKE_INFO_LEN]; +};