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authorteor <teor2345@gmail.com>2015-01-10 17:20:06 +1100
committerteor <teor2345@gmail.com>2015-01-10 17:20:06 +1100
commitf8ffb57bc4430ff9bbd7560eecdda4284b2799ba (patch)
tree7b73b0bf39d756c31bb62dbcd3c239864a6a46c8 /src/common/util.c
parentdebd7862bb6d641c13fe4ee019da633c683d740e (diff)
parent33df3e37ffecfed309a1a0f210a96620c0ebb837 (diff)
downloadtor-f8ffb57bc4430ff9bbd7560eecdda4284b2799ba.tar.gz
tor-f8ffb57bc4430ff9bbd7560eecdda4284b2799ba.zip
Merge branch 'master' of https://git.torproject.org/tor into bug13111-empty-key-files-fn-empty
Conflicts: src/or/connection_edge.c Merged in favour of origin.
Diffstat (limited to 'src/common/util.c')
-rw-r--r--src/common/util.c73
1 files changed, 67 insertions, 6 deletions
diff --git a/src/common/util.c b/src/common/util.c
index 2f01a83974..5e9dd18f02 100644
--- a/src/common/util.c
+++ b/src/common/util.c
@@ -1,6 +1,6 @@
/* Copyright (c) 2003, Roger Dingledine
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
- * Copyright (c) 2007-2014, The Tor Project, Inc. */
+ * Copyright (c) 2007-2015, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/**
@@ -513,6 +513,51 @@ round_uint64_to_next_multiple_of(uint64_t number, uint64_t divisor)
return number;
}
+/** Return the lowest x in [INT64_MIN, INT64_MAX] such that x is at least
+ * <b>number</b>, and x modulo <b>divisor</b> == 0. */
+int64_t
+round_int64_to_next_multiple_of(int64_t number, int64_t divisor)
+{
+ tor_assert(divisor > 0);
+ if (number >= 0 && INT64_MAX - divisor + 1 >= number)
+ number += divisor - 1;
+ number -= number % divisor;
+ return number;
+}
+
+/** Transform a random value <b>p</b> from the uniform distribution in
+ * [0.0, 1.0[ into a Laplace distributed value with location parameter
+ * <b>mu</b> and scale parameter <b>b</b> in [-Inf, Inf[. */
+double
+sample_laplace_distribution(double mu, double b, double p)
+{
+ tor_assert(p >= 0.0 && p < 1.0);
+ /* This is the "inverse cumulative distribution function" from:
+ * http://en.wikipedia.org/wiki/Laplace_distribution */
+ return mu - b * (p > 0.5 ? 1.0 : -1.0)
+ * tor_mathlog(1.0 - 2.0 * fabs(p - 0.5));
+}
+
+/** Add random noise between INT64_MIN and INT64_MAX coming from a
+ * Laplace distribution with mu = 0 and b = <b>delta_f</b>/<b>epsilon</b>
+ * to <b>signal</b> based on the provided <b>random</b> value in
+ * [0.0, 1.0[. */
+int64_t
+add_laplace_noise(int64_t signal, double random, double delta_f,
+ double epsilon)
+{
+ /* cast to int64_t intended */
+ int64_t noise = sample_laplace_distribution(
+ 0.0, /* just add noise, no further signal */
+ delta_f / epsilon, random);
+ if (noise > 0 && INT64_MAX - noise < signal)
+ return INT64_MAX;
+ else if (noise < 0 && INT64_MIN - noise > signal)
+ return INT64_MIN;
+ else
+ return signal + noise;
+}
+
/** Return the number of bits set in <b>v</b>. */
int
n_bits_set_u8(uint8_t v)
@@ -1223,6 +1268,9 @@ base16_decode(char *dest, size_t destlen, const char *src, size_t srclen)
return -1;
if (destlen < srclen/2 || destlen > SIZE_T_CEILING)
return -1;
+
+ memset(dest, 0, destlen);
+
end = src+srclen;
while (src<end) {
v1 = hex_decode_digit_(*src);
@@ -1656,15 +1704,18 @@ format_iso_time_nospace_usec(char *buf, const struct timeval *tv)
/** Given an ISO-formatted UTC time value (after the epoch) in <b>cp</b>,
* parse it and store its value in *<b>t</b>. Return 0 on success, -1 on
- * failure. Ignore extraneous stuff in <b>cp</b> separated by whitespace from
- * the end of the time string. */
+ * failure. Ignore extraneous stuff in <b>cp</b> after the end of the time
+ * string, unless <b>strict</b> is set. */
int
-parse_iso_time(const char *cp, time_t *t)
+parse_iso_time_(const char *cp, time_t *t, int strict)
{
struct tm st_tm;
unsigned int year=0, month=0, day=0, hour=0, minute=0, second=0;
- if (tor_sscanf(cp, "%u-%2u-%2u %2u:%2u:%2u", &year, &month,
- &day, &hour, &minute, &second) < 6) {
+ int n_fields;
+ char extra_char;
+ n_fields = tor_sscanf(cp, "%u-%2u-%2u %2u:%2u:%2u%c", &year, &month,
+ &day, &hour, &minute, &second, &extra_char);
+ if (strict ? (n_fields != 6) : (n_fields < 6)) {
char *esc = esc_for_log(cp);
log_warn(LD_GENERAL, "ISO time %s was unparseable", esc);
tor_free(esc);
@@ -1693,6 +1744,16 @@ parse_iso_time(const char *cp, time_t *t)
return tor_timegm(&st_tm, t);
}
+/** Given an ISO-formatted UTC time value (after the epoch) in <b>cp</b>,
+ * parse it and store its value in *<b>t</b>. Return 0 on success, -1 on
+ * failure. Reject the string if any characters are present after the time.
+ */
+int
+parse_iso_time(const char *cp, time_t *t)
+{
+ return parse_iso_time_(cp, t, 1);
+}
+
/** Given a <b>date</b> in one of the three formats allowed by HTTP (ugh),
* parse it into <b>tm</b>. Return 0 on success, negative on failure. */
int