X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fjournal%2Ffsprg.c;h=5c8d6d6febf0444557bd2142757a7fb8f0943327;hp=34ce3be96b707bca7844f38d7746f98de8ded31b;hb=79008bddf679a5e0900369950eb346c9fa687107;hpb=7560fffcd2531786b9c1ca657667a43e90331326

diff --git a/src/journal/fsprg.c b/src/journal/fsprg.c
index 34ce3be96..5c8d6d6fe 100644
--- a/src/journal/fsprg.c
+++ b/src/journal/fsprg.c
@@ -19,7 +19,13 @@
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  * 02110-1301  USA
+ */
+
+/*
+ * See "Practical Secure Logging: Seekable Sequential Key Generators"
+ * by G. A. Marson, B. Poettering for details:
  *
+ * http://eprint.iacr.org/2013/397
  */
 
 #include <gcrypt.h>
@@ -45,7 +51,7 @@ static void mpi_export(void *buf, size_t buflen, const gcry_mpi_t x) {
         assert(gcry_mpi_cmp_ui(x, 0) >= 0);
         len = (gcry_mpi_get_nbits(x) + 7) / 8;
         assert(len <= buflen);
-        memset(buf, 0, buflen);
+        memzero(buf, buflen);
         gcry_mpi_print(GCRYMPI_FMT_USG, buf + (buflen - len), len, &nwritten, x);
         assert(nwritten == len);
 }
@@ -74,7 +80,7 @@ static void uint64_export(void *buf, size_t buflen, uint64_t x) {
         ((uint8_t*) buf)[7] = (x >>  0) & 0xff;
 }
 
-static uint64_t uint64_import(const void *buf, size_t buflen) {
+_pure_ static uint64_t uint64_import(const void *buf, size_t buflen) {
         assert(buflen == 8);
         return
                 (uint64_t)(((uint8_t*) buf)[0]) << 56 |
@@ -160,7 +166,7 @@ static gcry_mpi_t twopowmodphi(uint64_t m, const gcry_mpi_t p) {
         gcry_mpi_sub_ui(phi, p, 1);
 
         /* count number of used bits in m */
-        for (n = 0; ((uint64_t)1 << n) <= m; n++)
+        for (n = 0; (1ULL << n) <= m; n++)
                 ;
 
         r = gcry_mpi_new(0);
@@ -300,7 +306,7 @@ void FSPRG_GenState0(void *state, const void *mpk, const void *seed, size_t seed
 
         memcpy(state, mpk, 2 + secpar / 8);
         mpi_export(state + 2 + 1 * secpar / 8, secpar / 8, x);
-        memset(state + 2 + 2 * secpar / 8, 0, 8);
+        memzero(state + 2 + 2 * secpar / 8, 8);
 
         gcry_mpi_release(n);
         gcry_mpi_release(x);