Merge remote-tracking branch 'asn/bug20852_v1'

This commit is contained in:
Nick Mathewson 2017-01-11 10:14:50 -05:00
commit 7892683e7e
5 changed files with 26 additions and 9 deletions

View file

@ -15,6 +15,7 @@
#include "config.h" #include "config.h"
#include "hs_common.h" #include "hs_common.h"
#include "hs_descriptor.h" #include "hs_descriptor.h"
#include "networkstatus.h"
#include "rendcache.h" #include "rendcache.h"
/* Directory descriptor cache. Map indexed by blinded key. */ /* Directory descriptor cache. Map indexed by blinded key. */
@ -366,6 +367,18 @@ hs_cache_handle_oom(time_t now, size_t min_remove_bytes)
return bytes_removed; return bytes_removed;
} }
/**
* Return the maximum size of an HS descriptor we are willing to accept as an
* HSDir.
*/
unsigned int
hs_cache_get_max_descriptor_size(void)
{
return (unsigned) networkstatus_get_param(NULL,
"HSV3MaxDescriptorSize",
HS_DESC_MAX_LEN, 1, INT32_MAX);
}
/* Initialize the hidden service cache subsystem. */ /* Initialize the hidden service cache subsystem. */
void void
hs_cache_init(void) hs_cache_init(void)

View file

@ -44,6 +44,8 @@ void hs_cache_free_all(void);
void hs_cache_clean_as_dir(time_t now); void hs_cache_clean_as_dir(time_t now);
size_t hs_cache_handle_oom(time_t now, size_t min_remove_bytes); size_t hs_cache_handle_oom(time_t now, size_t min_remove_bytes);
unsigned int hs_cache_get_max_descriptor_size(void);
/* Store and Lookup function. They are version agnostic that is depending on /* Store and Lookup function. They are version agnostic that is depending on
* the requested version of the descriptor, it will be re-routed to the * the requested version of the descriptor, it will be re-routed to the
* right function. */ * right function. */

View file

@ -15,13 +15,14 @@
#include "ed25519_cert.h" /* Trunnel interface. */ #include "ed25519_cert.h" /* Trunnel interface. */
#include "parsecommon.h" #include "parsecommon.h"
#include "rendcache.h" #include "rendcache.h"
#include "hs_cache.h"
#include "torcert.h" /* tor_cert_encode_ed22519() */ #include "torcert.h" /* tor_cert_encode_ed22519() */
/* Constant string value used for the descriptor format. */ /* Constant string value used for the descriptor format. */
#define str_hs_desc "hs-descriptor" #define str_hs_desc "hs-descriptor"
#define str_desc_cert "descriptor-signing-key-cert" #define str_desc_cert "descriptor-signing-key-cert"
#define str_rev_counter "revision-counter" #define str_rev_counter "revision-counter"
#define str_encrypted "encrypted" #define str_superencrypted "superencrypted"
#define str_signature "signature" #define str_signature "signature"
#define str_lifetime "descriptor-lifetime" #define str_lifetime "descriptor-lifetime"
/* Constant string value for the encrypted part of the descriptor. */ /* Constant string value for the encrypted part of the descriptor. */
@ -35,7 +36,7 @@
#define str_intro_point_start "\n" str_intro_point " " #define str_intro_point_start "\n" str_intro_point " "
/* Constant string value for the construction to encrypt the encrypted data /* Constant string value for the construction to encrypt the encrypted data
* section. */ * section. */
#define str_enc_hsdir_data "hsdir-encrypted-data" #define str_enc_hsdir_data "hsdir-superencrypted-data"
/* Prefix required to compute/verify HS desc signatures */ /* Prefix required to compute/verify HS desc signatures */
#define str_desc_sig_prefix "Tor onion service descriptor sig v3" #define str_desc_sig_prefix "Tor onion service descriptor sig v3"
@ -56,7 +57,7 @@ static token_rule_t hs_desc_v3_token_table[] = {
T1(str_lifetime, R3_DESC_LIFETIME, EQ(1), NO_OBJ), T1(str_lifetime, R3_DESC_LIFETIME, EQ(1), NO_OBJ),
T1(str_desc_cert, R3_DESC_SIGNING_CERT, NO_ARGS, NEED_OBJ), T1(str_desc_cert, R3_DESC_SIGNING_CERT, NO_ARGS, NEED_OBJ),
T1(str_rev_counter, R3_REVISION_COUNTER, EQ(1), NO_OBJ), T1(str_rev_counter, R3_REVISION_COUNTER, EQ(1), NO_OBJ),
T1(str_encrypted, R3_ENCRYPTED, NO_ARGS, NEED_OBJ), T1(str_superencrypted, R3_SUPERENCRYPTED, NO_ARGS, NEED_OBJ),
T1_END(str_signature, R3_SIGNATURE, EQ(1), NO_OBJ), T1_END(str_signature, R3_SIGNATURE, EQ(1), NO_OBJ),
END_OF_TABLE END_OF_TABLE
}; };
@ -751,7 +752,7 @@ desc_encode_v3(const hs_descriptor_t *desc,
desc->plaintext_data.revision_counter); desc->plaintext_data.revision_counter);
} }
/* Build the encrypted data section. */ /* Build the superencrypted data section. */
{ {
char *enc_b64_blob=NULL; char *enc_b64_blob=NULL;
if (encode_encrypted_data(desc, &enc_b64_blob) < 0) { if (encode_encrypted_data(desc, &enc_b64_blob) < 0) {
@ -762,7 +763,7 @@ desc_encode_v3(const hs_descriptor_t *desc,
"-----BEGIN MESSAGE-----\n" "-----BEGIN MESSAGE-----\n"
"%s" "%s"
"-----END MESSAGE-----", "-----END MESSAGE-----",
str_encrypted, enc_b64_blob); str_superencrypted, enc_b64_blob);
tor_free(enc_b64_blob); tor_free(enc_b64_blob);
} }
@ -1492,7 +1493,7 @@ desc_decode_plaintext_v3(smartlist_t *tokens,
} }
/* Extract the encrypted data section. */ /* Extract the encrypted data section. */
tok = find_by_keyword(tokens, R3_ENCRYPTED); tok = find_by_keyword(tokens, R3_SUPERENCRYPTED);
tor_assert(tok->object_body); tor_assert(tok->object_body);
if (strcmp(tok->object_type, "MESSAGE") != 0) { if (strcmp(tok->object_type, "MESSAGE") != 0) {
log_warn(LD_REND, "Service descriptor encrypted data section is invalid"); log_warn(LD_REND, "Service descriptor encrypted data section is invalid");
@ -1701,8 +1702,9 @@ hs_desc_decode_plaintext(const char *encoded,
tor_assert(encoded); tor_assert(encoded);
tor_assert(plaintext); tor_assert(plaintext);
/* Check that descriptor is within size limits. */
encoded_len = strlen(encoded); encoded_len = strlen(encoded);
if (encoded_len >= HS_DESC_MAX_LEN) { if (encoded_len >= hs_cache_get_max_descriptor_size()) {
log_warn(LD_REND, "Service descriptor is too big (%lu bytes)", log_warn(LD_REND, "Service descriptor is too big (%lu bytes)",
(unsigned long) encoded_len); (unsigned long) encoded_len);
goto err; goto err;

View file

@ -54,7 +54,7 @@
HS_DESC_ENCRYPTED_SALT_LEN + \ HS_DESC_ENCRYPTED_SALT_LEN + \
HS_DESC_PLAINTEXT_PADDING_MULTIPLE + DIGEST256_LEN HS_DESC_PLAINTEXT_PADDING_MULTIPLE + DIGEST256_LEN
/* Maximum length in bytes of a full hidden service descriptor. */ /* Maximum length in bytes of a full hidden service descriptor. */
#define HS_DESC_MAX_LEN 32768 // XXX justify #define HS_DESC_MAX_LEN 50000 /* 50kb max size */
/* The minimum amount of fields a descriptor should contain. The parsing of /* The minimum amount of fields a descriptor should contain. The parsing of
* the fields are version specific so the only required field, as a generic * the fields are version specific so the only required field, as a generic
* view of a descriptor, is 1 that is the version field. */ * view of a descriptor, is 1 that is the version field. */

View file

@ -154,7 +154,7 @@ typedef enum {
R3_DESC_LIFETIME, R3_DESC_LIFETIME,
R3_DESC_SIGNING_CERT, R3_DESC_SIGNING_CERT,
R3_REVISION_COUNTER, R3_REVISION_COUNTER,
R3_ENCRYPTED, R3_SUPERENCRYPTED,
R3_SIGNATURE, R3_SIGNATURE,
R3_CREATE2_FORMATS, R3_CREATE2_FORMATS,
R3_AUTHENTICATION_REQUIRED, R3_AUTHENTICATION_REQUIRED,