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schannel SSL: changes in schannel_connect_step2

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Process extra data buffer before returning from schannel_connect_step2.
Without this change I've seen WinCE hang when schannel_connect_step2
returns and calls Curl_socket_ready.

If the encrypted handshake does not fit in the intial buffer (seen with
large certificate chain), increasing the encrypted data buffer is necessary.

Fixed warning in curl_schannel.c line 1215.
This commit is contained in:
Mark Salisbury 2012-06-20 00:51:03 +02:00 committed by Yang Tse
parent 99b13f2741
commit 72a5813192
1 changed files with 127 additions and 94 deletions
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43
lib/curl_schannel.c
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@ -290,6 +290,7 @@ schannel_connect_step2(struct connectdata *conn, int sockindex)
SECURITY_STATUS sspi_status = SEC_E_OK;
TCHAR *host_name;
CURLcode code;
bool doread = TRUE;
infof(data, "schannel: SSL/TLS connection with %s port %hu (step 2/3)\n",
conn->host.name, conn->remote_port);
@ -305,6 +306,22 @@ 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_offset == connssl->encdata_length) {
if(connssl->encdata_length >= CURL_SCHANNEL_BUFFER_INIT_SIZE * 16)
return CURLE_OUT_OF_MEMORY;
/* increase internal encrypted data buffer */
connssl->encdata_length *= 2;
connssl->encdata_buffer = realloc(connssl->encdata_buffer,
connssl->encdata_length);
if(connssl->encdata_buffer == NULL) {
failf(data, "schannel: unable to re-allocate memory");
return CURLE_OUT_OF_MEMORY;
}
}
for (;;) {
if(doread) {
/* read encrypted handshake data from socket */
code = Curl_read_plain(conn->sock[sockindex],
(char *) (connssl->encdata_buffer + connssl->encdata_offset),
@ -325,6 +342,7 @@ schannel_connect_step2(struct connectdata *conn, int sockindex)
/* increase encrypted data buffer offset */
connssl->encdata_offset += nread;
}
infof(data, "schannel: encrypted data buffer: offset %zu length %zu\n",
connssl->encdata_offset, connssl->encdata_length);
@ -346,7 +364,8 @@ schannel_connect_step2(struct connectdata *conn, int sockindex)
}
/* copy received handshake data into input buffer */
memcpy(inbuf[0].pvBuffer, connssl->encdata_buffer, connssl->encdata_offset);
memcpy(inbuf[0].pvBuffer, connssl->encdata_buffer,
connssl->encdata_offset);
#ifdef UNICODE
host_name = Curl_convert_UTF8_to_wchar(conn->host.name);
@ -415,20 +434,34 @@ schannel_connect_step2(struct connectdata *conn, int sockindex)
/* check if there was additional remaining encrypted data */
if(inbuf[1].BufferType == SECBUFFER_EXTRA && inbuf[1].cbBuffer > 0) {
infof(data, "schannel: encrypted data length: %lu\n", inbuf[1].cbBuffer);
/* check if the remaining data is less than the total amount
* and therefore begins after the already processed data
/*
There are two cases where we could be getting extra data here:
1) If we're renegotiating a connection and the handshake is already
complete (from the server perspective), it can encrypted app data
(not handshake data) in an extra buffer at this point.
2) (sspi_status == SEC_I_CONTINUE_NEEDED) We are negotiating a
connection and this extra data is part of the handshake.
We should process the data immediately; waiting for the socket to
be ready may fail since the server is done sending handshake data.
*/
/* check if the remaining data is less than the total amount
and therefore begins after the already processed data */
if(connssl->encdata_offset > inbuf[1].cbBuffer) {
memmove(connssl->encdata_buffer,
(connssl->encdata_buffer + connssl->encdata_offset) -
inbuf[1].cbBuffer, inbuf[1].cbBuffer);
connssl->encdata_offset = inbuf[1].cbBuffer;
if(sspi_status == SEC_I_CONTINUE_NEEDED) {
doread = FALSE;
continue;
}
}
}
else {
connssl->encdata_offset = 0;
}
break;
}
/* check if the handshake needs to be continued */
if(sspi_status == SEC_I_CONTINUE_NEEDED) {
@ -1229,7 +1262,7 @@ static CURLcode verify_certificate(struct connectdata *conn, int sockindex)
failf(data, "schannel: CertGetNameString() certificate hostname "
"(%s) did not match connection (%s)",
_cert_hostname, conn->host.name);
free(_cert_hostname);
free((void *)_cert_hostname);
}
free(hostname);
}