Commit fbf35608 authored by Marc Hoersken's avatar Marc Hoersken
Browse files

curl_schannel: Removed buffer limit and optimized buffer strategy 

Since there are servers that seem to return very big encrypted
data packages, we need to be able to handle those without having
an internal size limit. To avoid the buffer growing to fast to
early the initial size was decreased and the minimum free space
in the buffer was decreased as well.
parent 07593b24

lib/curl_schannel.c

+5 −22
Original line number Diff line number Diff line
@@ -302,12 +302,7 @@ schannel_connect_step2(struct connectdata *conn, int sockindex) 


  /* if we need a bigger buffer to read a full message, increase buffer now */

  if(connssl->encdata_length - connssl->encdata_offset <

     CURL_SCHANNEL_BUFFER_MIN_SIZE) {

    if(connssl->encdata_length >= CURL_SCHANNEL_BUFFER_MAX_SIZE) {

      failf(data, "schannel: memory buffer size limit reached");

      return CURLE_OUT_OF_MEMORY;

    }



     CURL_SCHANNEL_BUFFER_FREE_SIZE) {

    /* increase internal encrypted data buffer */

    connssl->encdata_length *= CURL_SCHANNEL_BUFFER_STEP_FACTOR;

    connssl->encdata_buffer = realloc(connssl->encdata_buffer,
@@ -831,13 +826,7 @@ schannel_recv(struct connectdata *conn, int sockindex, 


  /* increase buffer in order to fit the requested amount of data */

  while(connssl->encdata_length - connssl->encdata_offset <

        CURL_SCHANNEL_BUFFER_MIN_SIZE || connssl->encdata_length < len) {

    if(connssl->encdata_length >= CURL_SCHANNEL_BUFFER_MAX_SIZE) {

      failf(data, "schannel: memory buffer size limit reached");

      *err = CURLE_OUT_OF_MEMORY;

      return -1;

    }



        CURL_SCHANNEL_BUFFER_FREE_SIZE || connssl->encdata_length < len) {

    /* increase internal encrypted data buffer */

    connssl->encdata_length *= CURL_SCHANNEL_BUFFER_STEP_FACTOR;

    connssl->encdata_buffer = realloc(connssl->encdata_buffer,
@@ -907,16 +896,10 @@ schannel_recv(struct connectdata *conn, int sockindex, 
              inbuf[1].cbBuffer);



        /* increase buffer in order to fit the received amount of data */

        size = inbuf[1].cbBuffer > CURL_SCHANNEL_BUFFER_MIN_SIZE ?

               inbuf[1].cbBuffer : CURL_SCHANNEL_BUFFER_MIN_SIZE;

        size = inbuf[1].cbBuffer > CURL_SCHANNEL_BUFFER_FREE_SIZE ?

               inbuf[1].cbBuffer : CURL_SCHANNEL_BUFFER_FREE_SIZE;

        while(connssl->decdata_length - connssl->decdata_offset < size ||

              connssl->decdata_length < len) {

          if(connssl->decdata_length >= CURL_SCHANNEL_BUFFER_MAX_SIZE) {

            failf(data, "schannel: memory buffer size limit reached");

            *err = CURLE_OUT_OF_MEMORY;

            return -1;

          }



          /* increase internal decrypted data buffer */

          connssl->decdata_length *= CURL_SCHANNEL_BUFFER_STEP_FACTOR;

          connssl->decdata_buffer = realloc(connssl->decdata_buffer,

lib/curl_schannel.h

+2 −8
Original line number Diff line number Diff line
@@ -93,14 +93,8 @@ 
#endif





#ifdef BUFSIZE

#define CURL_SCHANNEL_BUFFER_INIT_SIZE  BUFSIZE

#else

#define CURL_SCHANNEL_BUFFER_INIT_SIZE   4096

#endif



#define CURL_SCHANNEL_BUFFER_MIN_SIZE    CURL_SCHANNEL_BUFFER_INIT_SIZE / 2

#define CURL_SCHANNEL_BUFFER_MAX_SIZE    CURL_SCHANNEL_BUFFER_INIT_SIZE * 128

#define CURL_SCHANNEL_BUFFER_FREE_SIZE   1024

#define CURL_SCHANNEL_BUFFER_STEP_FACTOR 2