From: Wilfried Goesgens <dothebart@citadel.org>
Date: Mon, 6 Jan 2014 23:38:27 +0000 (+0100)
Subject: BASE64: add stream handler for base 64 decoding - make shure its not called for to... 
X-Git-Tag: v9.01~149
X-Git-Url: https://code.citadel.org/?p=citadel.git;a=commitdiff_plain;h=e2c97f4b0f5420b21f491d6e61dca580f8772d39

BASE64: add stream handler for base 64 decoding - make shure its not called for to small chunks - else it will eat cpu.
---

diff --git a/libcitadel/lib/libcitadel.h b/libcitadel/lib/libcitadel.h
index a1aacb5fb..7dd18e64c 100644
--- a/libcitadel/lib/libcitadel.h
+++ b/libcitadel/lib/libcitadel.h
@@ -338,6 +338,14 @@ void StrBuf_RFC822_2_Utf8(StrBuf *Target,
 /* deprecated old version: */
 void StrBuf_RFC822_to_Utf8(StrBuf *Target, const StrBuf *DecodeMe, const StrBuf* DefaultCharset, StrBuf *FoundCharset);
 
+typedef enum __eStreamType {
+	eBase64Decode
+} eStreamType;
+
+void *StrBufNewStreamContext(eStreamType type);
+void StrBufDestroyStreamContext(eStreamType type, void **Stream);
+void StrBufStreamDecodeTo(StrBuf *Target, const StrBuf *In, const char* pIn, long pInLen, void *Stream);
+
 int StrBufDecodeBase64(StrBuf *Buf);
 int StrBufDecodeBase64To(const StrBuf *BufIn, StrBuf *BufOut);
 int StrBufDecodeHex(StrBuf *Buf);
diff --git a/libcitadel/lib/stringbuf.c b/libcitadel/lib/stringbuf.c
index 547037751..5e89ea2f1 100644
--- a/libcitadel/lib/stringbuf.c
+++ b/libcitadel/lib/stringbuf.c
@@ -32,6 +32,9 @@
 
 #include "libcitadel.h"
 
+#include "b64/cencode.h"
+#include "b64/cdecode.h"
+
 #ifdef HAVE_ICONV
 #include <iconv.h>
 #endif
@@ -2843,6 +2846,56 @@ int StrBufDecodeBase64To(const StrBuf *BufIn, StrBuf *BufOut)
 	return BufOut->BufUsed;
 }
 
+void *StrBufNewStreamContext(eStreamType type)
+{
+	base64_decodestate *state;;
+
+	switch (type)
+	{
+	case eBase64Decode:
+		state = (base64_decodestate*) malloc(sizeof(base64_decodestate));
+		base64_init_decodestate(state);
+		return state;
+		break;
+	}
+	return NULL;
+}
+
+void StrBufDestroyStreamContext(eStreamType type, void **Stream)
+{
+	switch (type)
+	{
+	case eBase64Decode:
+		free(*Stream);
+		*Stream = NULL;
+		break;
+	}
+}
+void StrBufStreamDecodeTo(StrBuf *Target, const StrBuf *In, const char* pIn, long pInLen, void *Stream)
+{
+	base64_decodestate *state = Stream;
+	long ExpectLen;
+
+	if (In != NULL)
+	{
+		pIn = In->buf;
+		pInLen = In->BufUsed;
+	}
+	if ((pIn == NULL) || (Stream == NULL))
+		return;
+	
+	ExpectLen = (pInLen / 4) * 3;
+
+	if (Target->BufSize - Target->BufUsed < ExpectLen)
+	{
+		IncreaseBuf(Target, 1, Target->BufUsed + ExpectLen + 1);
+	}
+
+	ExpectLen = base64_decode_block(pIn, pInLen, Target->buf + Target->BufUsed, state);
+	Target->BufUsed += ExpectLen;
+	Target->buf[Target->BufUsed] = '\0';
+}
+
 /**
  * @ingroup StrBuf_DeEnCoder
  * @brief decode a buffer from base 64 encoding; destroys original