From 16c9148220bd9588a0713b835f7d1be43755b3ec Mon Sep 17 00:00:00 2001
From: "Dr. Stephen Henson" <steve@openssl.org>
Date: Tue, 3 Jun 2003 00:11:37 +0000
Subject: [PATCH] Move the base64 BIO fixes to 0.9.7-stable

---
 CHANGES              |  7 +++++++
 crypto/evp/bio_b64.c | 38 ++++++++++++++++++++++++++++----------
 2 files changed, 35 insertions(+), 10 deletions(-)

diff --git a/CHANGES b/CHANGES
index b1636083b1..317f75fd14 100644
--- a/CHANGES
+++ b/CHANGES
@@ -4,6 +4,13 @@
 
  Changes between 0.9.7b and 0.9.7c  [xx XXX 2003]
 
+  *) Various fixes to base64 BIO and non blocking I/O. On write 
+     flushes were not handled properly if the BIO retried. On read
+     data was not being buffered properly and had various logic bugs.
+     This also affects blocking I/O when the data being decoded is a
+     certain size.
+     [Steve Henson]
+
   *) Various S/MIME bugfixes and compatibility changes:
      output correct application/pkcs7 MIME type if
      PKCS7_NOOLDMIMETYPE is set. Tolerate some broken signatures.
diff --git a/crypto/evp/bio_b64.c b/crypto/evp/bio_b64.c
index 6e550f6a43..33349c2f98 100644
--- a/crypto/evp/bio_b64.c
+++ b/crypto/evp/bio_b64.c
@@ -184,7 +184,9 @@ static int b64_read(BIO *b, char *out, int outl)
 	ret_code=0;
 	while (outl > 0)
 		{
-		if (ctx->cont <= 0) break;
+
+		if (ctx->cont <= 0)
+			break;
 
 		i=BIO_read(b->next_bio,&(ctx->tmp[ctx->tmp_len]),
 			B64_BLOCK_SIZE-ctx->tmp_len);
@@ -195,11 +197,21 @@ static int b64_read(BIO *b, char *out, int outl)
 
 			/* Should be continue next time we are called? */
 			if (!BIO_should_retry(b->next_bio))
+				{
 				ctx->cont=i;
-			/* else we should continue when called again */
-			break;
+				/* If buffer empty break */
+				if(ctx->tmp_len == 0)
+					break;
+				/* Fall through and process what we have */
+				else
+					i = 0;
+				}
+			/* else we retry and add more data to buffer */
+			else
+				break;
 			}
 		i+=ctx->tmp_len;
+		ctx->tmp_len = i;
 
 		/* We need to scan, a line at a time until we
 		 * have a valid line if we are starting. */
@@ -255,8 +267,12 @@ static int b64_read(BIO *b, char *out, int outl)
 				 * reading until a new line. */
 				if (p == (unsigned char *)&(ctx->tmp[0]))
 					{
-					ctx->tmp_nl=1;
-					ctx->tmp_len=0;
+					/* Check buffer full */
+					if (i == B64_BLOCK_SIZE)
+						{
+						ctx->tmp_nl=1;
+						ctx->tmp_len=0;
+						}
 					}
 				else if (p != q) /* finished on a '\n' */
 					{
@@ -271,6 +287,11 @@ static int b64_read(BIO *b, char *out, int outl)
 			else
 				ctx->tmp_len=0;
 			}
+		/* If buffer isn't full and we can retry then
+		 * restart to read in more data.
+		 */
+		else if ((i < B64_BLOCK_SIZE) && (ctx->cont > 0))
+			continue;
 
 		if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)
 			{
@@ -310,8 +331,8 @@ static int b64_read(BIO *b, char *out, int outl)
 			i=EVP_DecodeUpdate(&(ctx->base64),
 				(unsigned char *)ctx->buf,&ctx->buf_len,
 				(unsigned char *)ctx->tmp,i);
+			ctx->tmp_len = 0;
 			}
-		ctx->cont=i;
 		ctx->buf_off=0;
 		if (i < 0)
 			{
@@ -484,10 +505,7 @@ again:
 			{
 			i=b64_write(b,NULL,0);
 			if (i < 0)
-				{
-				ret=i;
-				break;
-				}
+				return i;
 			}
 		if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)
 			{
-- 
2.25.1