sr: Extract shared SR functions

Move most of the shared random functions that are needed outside of the
dirauth module.

At this commit, because dirvote.c hasn't been refactor, it doesn't compile
because some SR functions need a dirvote function.

Furthermore, 5 functions haven't been touched yet because they are dirauth
only but are in used in other C files than the dirauth module ones.

No code behavior change. Only moving code around.

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

1 files changed, 1 insertions, 162 deletions

diff --git a/src/or/dirauth/shared_random.c b/src/or/dirauth/shared_random.c
index e9644adf9e..5dee77dce9 100644
--- a/src/or/dirauth/shared_random.c
+++ b/src/or/dirauth/shared_random.c
@@ -96,6 +96,7 @@
 #include "router.h"
 #include "routerlist.h"
 #include "shared_random_state.h"
+#include "shared_random_common.h"
 #include "util.h"
 
 #include "dirauth/dirvote.h"
@@ -499,20 +500,6 @@ get_vote_line_from_commit(const sr_commit_t *commit, sr_phase_t phase)
   return vote_line;
 }
 
-/* Convert a given srv object to a string for the control port. This doesn't
- * fail and the srv object MUST be valid. */
-static char *
-srv_to_control_string(const sr_srv_t *srv)
-{
-  char *srv_str;
-  char srv_hash_encoded[SR_SRV_VALUE_BASE64_LEN + 1];
-  tor_assert(srv);
-
-  sr_srv_encode(srv_hash_encoded, sizeof(srv_hash_encoded), srv);
-  tor_asprintf(&srv_str, "%s", srv_hash_encoded);
-  return srv_str;
-}
-
 /* Return a heap allocated string that contains the given <b>srv</b> string
  * representation formatted for a networkstatus document using the
  * <b>key</b> as the start of the line. This doesn't return NULL. */
@@ -875,27 +862,6 @@ get_majority_srv_from_votes(const smartlist_t *votes, int current)
   return the_srv;
 }
 
-/* Encode the given shared random value and put it in dst. Destination
- * buffer must be at least SR_SRV_VALUE_BASE64_LEN plus the NULL byte. */
-void
-sr_srv_encode(char *dst, size_t dst_len, const sr_srv_t *srv)
-{
-  int ret;
-  /* Extra byte for the NULL terminated char. */
-  char buf[SR_SRV_VALUE_BASE64_LEN + 1];
-
-  tor_assert(dst);
-  tor_assert(srv);
-  tor_assert(dst_len >= sizeof(buf));
-
-  ret = base64_encode(buf, sizeof(buf), (const char *) srv->value,
-                      sizeof(srv->value), 0);
-  /* Always expect the full length without the NULL byte. */
-  tor_assert(ret == (sizeof(buf) - 1));
-  tor_assert(ret <= (int) dst_len);
-  strlcpy(dst, buf, dst_len);
-}
-
 /* Free a commit object. */
 void
 sr_commit_free_(sr_commit_t *commit)
@@ -1037,55 +1003,6 @@ sr_compute_srv(void)
   tor_free(reveals);
 }
 
-/* Parse a list of arguments from a SRV value either from a vote, consensus
- * or from our disk state and return a newly allocated srv object. NULL is
- * returned on error.
- *
- * The arguments' order:
- *    num_reveals, value
- */
-sr_srv_t *
-sr_parse_srv(const smartlist_t *args)
-{
-  char *value;
-  int ok, ret;
-  uint64_t num_reveals;
-  sr_srv_t *srv = NULL;
-
-  tor_assert(args);
-
-  if (smartlist_len(args) < 2) {
-    goto end;
-  }
-
-  /* First argument is the number of reveal values */
-  num_reveals = tor_parse_uint64(smartlist_get(args, 0),
-                                 10, 0, UINT64_MAX, &ok, NULL);
-  if (!ok) {
-    goto end;
-  }
-  /* Second and last argument is the shared random value it self. */
-  value = smartlist_get(args, 1);
-  if (strlen(value) != SR_SRV_VALUE_BASE64_LEN) {
-    goto end;
-  }
-
-  srv = tor_malloc_zero(sizeof(*srv));
-  srv->num_reveals = num_reveals;
-  /* We subtract one byte from the srclen because the function ignores the
-   * '=' character in the given buffer. This is broken but it's a documented
-   * behavior of the implementation. */
-  ret = base64_decode((char *) srv->value, sizeof(srv->value), value,
-                      SR_SRV_VALUE_BASE64_LEN - 1);
-  if (ret != sizeof(srv->value)) {
-    tor_free(srv);
-    srv = NULL;
-    goto end;
-  }
- end:
-  return srv;
-}
-
 /* Parse a commit from a vote or from our disk state and return a newly
  * allocated commit object. NULL is returned on error.
  *
@@ -1353,84 +1270,6 @@ sr_save_and_cleanup(void)
   sr_cleanup();
 }
 
-/* Return the current SRV string representation for the control port. Return a
- * newly allocated string on success containing the value else "" if not found
- * or if we don't have a valid consensus yet. */
-char *
-sr_get_current_for_control(void)
-{
-  char *srv_str;
-  const networkstatus_t *c = networkstatus_get_latest_consensus();
-  if (c && c->sr_info.current_srv) {
-    srv_str = srv_to_control_string(c->sr_info.current_srv);
-  } else {
-    srv_str = tor_strdup("");
-  }
-  return srv_str;
-}
-
-/* Return the previous SRV string representation for the control port. Return
- * a newly allocated string on success containing the value else "" if not
- * found or if we don't have a valid consensus yet. */
-char *
-sr_get_previous_for_control(void)
-{
-  char *srv_str;
-  const networkstatus_t *c = networkstatus_get_latest_consensus();
-  if (c && c->sr_info.previous_srv) {
-    srv_str = srv_to_control_string(c->sr_info.previous_srv);
-  } else {
-    srv_str = tor_strdup("");
-  }
-  return srv_str;
-}
-
-/* Return current shared random value from the latest consensus. Caller can
- * NOT keep a reference to the returned pointer. Return NULL if none. */
-const sr_srv_t *
-sr_get_current(const networkstatus_t *ns)
-{
-  const networkstatus_t *consensus;
-
-  /* Use provided ns else get a live one */
-  if (ns) {
-    consensus = ns;
-  } else {
-    consensus = networkstatus_get_live_consensus(approx_time());
-  }
-  /* Ideally we would never be asked for an SRV without a live consensus. Make
-   * sure this assumption is correct. */
-  tor_assert_nonfatal(consensus);
-
-  if (consensus) {
-    return consensus->sr_info.current_srv;
-  }
-  return NULL;
-}
-
-/* Return previous shared random value from the latest consensus. Caller can
- * NOT keep a reference to the returned pointer. Return NULL if none. */
-const sr_srv_t *
-sr_get_previous(const networkstatus_t *ns)
-{
-  const networkstatus_t *consensus;
-
-  /* Use provided ns else get a live one */
-  if (ns) {
-    consensus = ns;
-  } else {
-    consensus = networkstatus_get_live_consensus(approx_time());
-  }
-  /* Ideally we would never be asked for an SRV without a live consensus. Make
-   * sure this assumption is correct. */
-  tor_assert_nonfatal(consensus);
-
-  if (consensus) {
-    return consensus->sr_info.previous_srv;
-  }
-  return NULL;
-}
-
 #ifdef TOR_UNIT_TESTS
 
 /* Set the global value of number of SRV agreements so the test can play