Bug 1717610 - Add function to get seconds from epoch from pkix::Time r=bbeurdouche,keeler

We need this function for the rewrite of CertVerifier::VerifyCertificateTransparencyPolicy in order to calculate a certificate's lifetime in months.

Differential Revision: https://phabricator.services.mozilla.com/D118525

2 files changed, 19 insertions, 0 deletions

diff --git a/lib/mozpkix/include/pkix/Time.h b/lib/mozpkix/include/pkix/Time.h
index 8aea5479b..20cef5160 100644
--- a/lib/mozpkix/include/pkix/Time.h
+++ b/lib/mozpkix/include/pkix/Time.h
@@ -111,6 +111,9 @@ Time Now();
 // Note the epoch is the unix epoch (ie 00:00:00 UTC, 1 January 1970)
 Time TimeFromEpochInSeconds(uint64_t secondsSinceEpoch);
 
+// Note the epoch is the unix epoch (ie 00:00:00 UTC, 1 January 1970)
+Result SecondsSinceEpochFromTime(Time time, uint64_t* outSeconds);
+
 class Duration final {
  public:
   Duration(Time timeA, Time timeB)
@@ -129,6 +132,8 @@ class Duration final {
   }
 
  private:
+  friend Result SecondsSinceEpochFromTime(Time time, uint64_t* outSeconds);
+
   uint64_t durationInSeconds;
 };
 }
diff --git a/lib/mozpkix/lib/pkixtime.cpp b/lib/mozpkix/lib/pkixtime.cpp
index 38e063804..ba545d2e9 100644
--- a/lib/mozpkix/lib/pkixtime.cpp
+++ b/lib/mozpkix/lib/pkixtime.cpp
@@ -75,4 +75,18 @@ TimeFromEpochInSeconds(uint64_t secondsSinceEpoch)
   return TimeFromElapsedSecondsAD(seconds);
 }
 
+Result
+SecondsSinceEpochFromTime(Time time, uint64_t* outSeconds)
+{
+  if (!outSeconds) {
+    return Result::FATAL_ERROR_INVALID_ARGS;
+  }
+  Time epoch = TimeFromEpochInSeconds(0);
+  if (time < epoch) {
+    return Result::FATAL_ERROR_INVALID_ARGS;
+  }
+  *outSeconds = Duration(time, epoch).durationInSeconds;
+  return Result::Success;
+}
+
 } } // namespace mozilla::pkix