From 5dd40a1779cf6ec458ca2cb2fed8300ebb404e3b Mon Sep 17 00:00:00 2001
From: TLINDEN <git@daemon.de>
Date: Sun, 23 Feb 2014 11:03:49 +0100
Subject: [PATCH] fixed decoding and cached read

---
 ChangeLog          |  1 +
 libpcp/pcpstream.c | 21 ++++++++++++++++++---
 tests/Makefile.am  |  2 +-
 tests/streamtest.c | 20 ++++++++++++++++----
 4 files changed, 36 insertions(+), 8 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index f271d19..7e39ba8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -48,6 +48,7 @@
 	wrapper around file i/o or buffer i/o. It's used
 	in libpcp/crypto.c (more to follow), so it depends
 	on the caller if it works on files or on buffers.
+	Pcpstreams also automatically encode/decode Z85.
 
 	Lots of refactoring have been done to clear things
 	out and make the system work with the changes
diff --git a/libpcp/pcpstream.c b/libpcp/pcpstream.c
index eefbce6..7fcecbd 100644
--- a/libpcp/pcpstream.c
+++ b/libpcp/pcpstream.c
@@ -24,7 +24,8 @@
 Pcpstream *ps_init(void) {
   Pcpstream *stream = ucmalloc(sizeof(Pcpstream));
   stream->b = NULL;
-  stream->cache = buffer_new(32, "Pcpstreamcache");
+  stream->cache = NULL;
+  stream->next = NULL;
   stream->fd = NULL;
   stream->is_buffer = 0;
   stream->eof = 0;
@@ -57,11 +58,19 @@ Pcpstream *ps_new_outbuffer() {
 void ps_setdetermine(Pcpstream *stream, size_t blocksize) {
   stream->determine = 1;
   stream->blocksize = blocksize;
+  if(stream->cache == NULL) {
+    stream->cache = buffer_new(32, "Pcpstreamcache");
+    stream->next = buffer_new(32, "Pcpstreamcachenext");
+  }
 }
 
 void ps_armor(Pcpstream *stream, size_t blocksize) {
   stream->armor = 1;
   stream->blocksize = blocksize;
+  if(stream->cache == NULL) {
+    stream->cache = buffer_new(32, "Pcpstreamcache");
+    stream->next = buffer_new(32, "Pcpstreamcachenext");
+  }
 }
 
 size_t ps_read_raw(Pcpstream *stream, void *buf, size_t readbytes) {
@@ -97,7 +106,7 @@ size_t ps_read_raw(Pcpstream *stream, void *buf, size_t readbytes) {
    fetch (and decode) the next chunk, append it to cache and return from
    that */
 size_t ps_read_cached(Pcpstream *stream, void *buf, size_t readbytes) {
-  if(buffer_left(stream->cache) <= readbytes) {
+  if(buffer_left(stream->cache) <= readbytes && buffer_left(stream->cache) > 0) {
     /* enough left in current cache */
     return buffer_get_chunk(stream->cache, buf, readbytes);
   }
@@ -175,7 +184,7 @@ void ps_determine(Pcpstream *stream) {
   size_t got = ps_read_raw(stream, buf, stream->blocksize);
 
   /* check if it's binary or not */
-  if(_buffer_is_binary(buf, got) != 0) {
+  if(_buffer_is_binary(buf, got) == 0) {
     /* no, it's armored */
     stream->armor = 1;
     ps_read_decode(stream, stream->cache, buf, got);
@@ -364,6 +373,12 @@ size_t ps_print(Pcpstream *stream, const char * fmt, ...) {
 }
 
 void ps_close(Pcpstream *stream) {
+  if(stream->cache != NULL)
+    buffer_free(stream->cache);
+
+  if(stream->next != NULL)
+    buffer_free(stream->next);
+
   if(stream->is_buffer) {
     buffer_clear(stream->b);
     free(stream);
diff --git a/tests/Makefile.am b/tests/Makefile.am
index ddad80d..80bc842 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -20,7 +20,7 @@
 #
 
 AM_CFLAGS = -I../include/pcp -I../src -I../libpcp/scrypt/crypto -Wall -g
-check_PROGRAMS = col invalidkeys pwhashes gencheader statictest cpptest buffertest sample
+check_PROGRAMS = col invalidkeys pwhashes gencheader statictest cpptest buffertest sample streamtest
 
 gencheader_LDADD = ../libpcp/.libs/libpcp1.a
 gencheader_SOURCES = gencheader.c
diff --git a/tests/streamtest.c b/tests/streamtest.c
index ff8a694..36fcb62 100644
--- a/tests/streamtest.c
+++ b/tests/streamtest.c
@@ -10,30 +10,41 @@ int main() {
   unsigned char clear[8] = "ABCDEFGH";
   unsigned char key[8]   = "IxD8Lq1K";
   unsigned char crypt[8] = {0};
-  int blocks = 8;
+  int blocks = 48;
   int i = 0;
 
   if((out = fopen("teststream.out", "wb+")) == NULL) {
     fprintf(stderr, "oops, could not open file!\n");
     return 1;
   }
-  Pcpstream *pout = ps_new_file(out);
 
-  /* "encrypt" a couple of times into the file */
+  /* out output stream, z85 encoded, use z85 blocksize 8 */
+  Pcpstream *pout = ps_new_file(out);
+  ps_armor(pout, 8);
+
+  /* "encrypt" a couple of times into the output stream */
   for(i=0; i<blocks; i++) {
     memcpy(crypt, clear, 8);
     _xorbuf(key, crypt, 8);
     ps_write(pout, crypt, 8);
   }
+
+  /* done, put cached buffers out and close */
+  ps_finish(pout);
   ps_close(pout);
   fclose(out);
 
-  /* read it in again using an in and an out stream */
+  /* read it in again using an input stream */
   if((in = fopen("teststream.out", "rb")) == NULL) {
     fprintf(stderr, "oops, could not open file!\n");
     return 1;
   }
   Pcpstream *pin = ps_new_file(in);
+
+  /* enable autmatically encoding detection.
+     set blocksize to 10, because:
+     8 + (5 - (8 % 5)) == 10 */
+  ps_setdetermine(pin, 10);
   
   /* we'll use this stream to put the "decrypted" data in.
      note, that this could be a file as well.  */
@@ -44,6 +55,7 @@ int main() {
     ps_read(pin, crypt, 8);
     _xorbuf(key, crypt, 8);
     ps_write(pclear, crypt, 8);
+    memset(crypt,0,8);
   }
   ps_close(pin);
   fclose(in);