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#include "proto.h"
#include "tcp.h"
#include "url.h"
#include "etherboot.h"
/* The block size is currently chosen to be 512 bytes. This means, we can
allocate the receive buffer on the stack, but it results in a noticeable
performance penalty.
This is what needs to be done in order to increase the block size:
- size negotiation needs to be implemented in TCP
- the buffer needs to be allocated on the heap
- path MTU discovery needs to be implemented
*/ /***/ /* FIXME */
#define BLOCKSIZE TFTP_DEFAULTSIZE_PACKET
/**************************************************************************
SEND_TCP_CALLBACK - Send data using TCP
**************************************************************************/
struct send_recv_state {
struct buffer *recv_buffer;
char *send_buffer;
int send_length;
int bytes_sent;
int bytes_received;
enum { RESULT_CODE, HEADER, DATA, ERROR, MOVED } recv_state;
int rc;
char *url;
};
static int send_tcp_request(int length, void *buffer, void *ptr) {
struct send_recv_state *state = (struct send_recv_state *)ptr;
if (length > state->send_length - state->bytes_sent)
length = state->send_length - state->bytes_sent;
memcpy(buffer, state->send_buffer + state->bytes_sent, length);
state->bytes_sent += length;
return (length);
}
/**************************************************************************
RECV_TCP_CALLBACK - Receive data using TCP
**************************************************************************/
static int recv_tcp_request(int length, const void *buffer, void *ptr) {
struct send_recv_state *state = (struct send_recv_state *)ptr;
/* Assume that the lines in an HTTP header do not straddle a packet */
/* boundary. This is probably a reasonable assumption */
if (state->recv_state == RESULT_CODE) {
while (length > 0) {
/* Find HTTP result code */
if (*(const char *)buffer == ' ') {
const char *ptr = ((const char *)buffer) + 1;
int rc = strtoul(ptr, &ptr, 10);
if (ptr >= (const char *)buffer + length) {
state->recv_state = ERROR;
DBG ( "HTTP got bad result code\n" );
return 0;
}
state->rc = rc;
state->recv_state = HEADER;
DBG ( "HTTP got result code %d\n", rc );
goto header;
}
++(const char *)buffer;
length--;
}
state->recv_state = ERROR;
DBG ( "HTTP got no result code\n" );
return 0;
}
if (state->recv_state == HEADER) {
header: while (length > 0) {
/* Check for HTTP redirect */
if (state->rc >= 300 && state->rc < 400 &&
!memcmp(buffer, "Location: ", 10)) {
char *p;
state->url = p = ( char * ) buffer + 10;
while ( *p > ' ' ) {
p++;
}
*p = '\0';
state->recv_state = MOVED;
DBG ( "HTTP got redirect to %s\n",
state->url );
return 1;
}
/* Find beginning of line */
while (length > 0) {
length--;
if (*((const char *)buffer)++ == '\n')
break;
}
/* Check for end of header */
if (length >= 2 && !memcmp(buffer, "\r\n", 2)) {
state->recv_state = DATA;
buffer += 2;
length -= 2;
break;
}
}
}
if (state->recv_state == DATA) {
DBG2 ( "HTTP received %d bytes\n", length );
if ( ! fill_buffer ( state->recv_buffer, buffer,
state->bytes_received, length ) )
return 0;
state->bytes_received += length;
}
return 1;
}
/**************************************************************************
HTTP_GET - Get data using HTTP
**************************************************************************/
static int http ( char *url, struct sockaddr_in *server __unused,
char *file __unused, struct buffer *buffer ) {
struct protocol *proto;
struct sockaddr_in http_server = *server;
char *filename;
static const char GET[] = "GET /%s HTTP/1.0\r\n\r\n";
struct send_recv_state state;
int length;
state.rc = -1;
state.url = url;
state.recv_buffer = buffer;
while ( 1 ) {
length = strlen ( filename ) + strlen ( GET );
{
char send_buf[length];
sprintf ( send_buf, GET, filename );
state.send_buffer = send_buf;
state.send_length = strlen ( send_buf );
state.bytes_sent = 0;
state.bytes_received = 0;
state.recv_state = RESULT_CODE;
tcp_transaction ( server->sin_addr.s_addr,
server->sin_port, &state,
send_tcp_request, recv_tcp_request );
}
if ( state.recv_state == MOVED ) {
if ( ! parse_url ( state.url, &proto,
&http_server, &filename ) ) {
printf ( "Invalid redirect URL %s\n",
state.url );
return 0;
}
continue;
}
break;
}
if ( state.rc != 200 ) {
printf ( "Failed to download %s (rc = %d)\n",
state.url, state.rc );
return 0;
}
return 1;
}
static struct protocol http_protocol __protocol = {
.name = "http",
.default_port = 80,
.load = http,
};
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