/* Return a usable socket descriptor after proxy negotiation, or -1 on any
error. If any bytes are received through the proxy after negotiation, they
are written to stdout. */
static int do_proxy_http(void)
{
struct socket_buffer sockbuf;
char *request;
char *status_line, *header;
char *remainder;
size_t len;
int sd, code;
int n;
sd = do_connect(SOCK_STREAM);
if (sd == -1) {
loguser("Proxy connection failed: %s.\n", socket_strerror(socket_errno()));
return -1;
}
status_line = NULL;
header = NULL;
/* First try a request with no authentication. */
request = http_connect_request(&httpconnect, &n);
if (send(sd, request, n, 0) < 0) {
loguser("Error sending proxy request: %s.\n", socket_strerror(socket_errno()));
free(request);
return -1;
}
free(request);
socket_buffer_init(&sockbuf, sd);
if (http_read_status_line(&sockbuf, &status_line) != 0) {
loguser("Error reading proxy response Status-Line.\n");
goto bail;
}
code = http_parse_status_line_code(status_line);
logdebug("Proxy returned status code %d.\n", code);
free(status_line);
status_line = NULL;
if (http_read_header(&sockbuf, &header) != 0) {
loguser("Error reading proxy response header.\n");
goto bail;
}
if (code == 407 && o.proxy_auth != NULL) {
struct http_header *h;
struct http_challenge challenge;
close(sd);
sd = -1;
if (http_parse_header(&h, header) != 0) {
loguser("Error parsing proxy response header.\n");
goto bail;
}
free(header);
header = NULL;
if (http_header_get_proxy_challenge(h, &challenge) == NULL) {
loguser("Error getting Proxy-Authenticate challenge.\n");
http_header_free(h);
goto bail;
}
http_header_free(h);
sd = do_connect(SOCK_STREAM);
if (sd == -1) {
loguser("Proxy reconnection failed: %s.\n", socket_strerror(socket_errno()));
goto bail;
}
request = http_connect_request_auth(&httpconnect, &n, &challenge);
if (request == NULL) {
loguser("Error building Proxy-Authorization header.\n");
http_challenge_free(&challenge);
goto bail;
}
logdebug("Reconnection header:\n%s", request);
if (send(sd, request, n, 0) < 0) {
loguser("Error sending proxy request: %s.\n", socket_strerror(socket_errno()));
free(request);
http_challenge_free(&challenge);
goto bail;
}
free(request);
http_challenge_free(&challenge);
socket_buffer_init(&sockbuf, sd);
if (http_read_status_line(&sockbuf, &status_line) != 0) {
loguser("Error reading proxy response Status-Line.\n");
goto bail;
}
code = http_parse_status_line_code(status_line);
logdebug("Proxy returned status code %d.\n", code);
free(status_line);
status_line = NULL;
if (http_read_header(&sockbuf, &header) != 0) {
loguser("Error reading proxy response header.\n");
goto bail;
}
}
free(header);
header = NULL;
if (code != 200) {
loguser("Proxy returned status code %d.\n", code);
return -1;
}
remainder = socket_buffer_remainder(&sockbuf, &len);
Write(STDOUT_FILENO, remainder, len);
return sd;
bail:
if (sd != -1)
close(sd);
if (status_line != NULL)
free(status_line);
if (header != NULL)
free(header);
return -1;
}
/* Do a GET, HEAD, or POST transaction. */
static int do_transaction(struct http_request *request,
struct socket_buffer *client_sock, struct socket_buffer *server_sock)
{
char buf[BUFSIZ];
struct http_response response;
char *line;
char *request_str, *response_str;
size_t len;
int code, n;
/* We don't handle the chunked transfer encoding, which in the absence of a
Content-Length is the only way we know the end of a request body. RFC
2616, section 4.4 says, "If a request contains a message-body and a
Content-Length is not given, the server SHOULD respond with 400 (bad
request) if it cannot determine the length of the message, or with 411
(length required) if it wishes to insist on receiving a valid
Content-Length." */
if (strcmp(request->method, "POST") == 0 && request->content_length == 0) {
if (o.debug)
logdebug("POST request with no Content-Length.\n");
return 400;
}
/* The version we use to talk to the server. */
request->version = HTTP_10;
/* Remove headers that only apply to our connection with the client. */
code = http_header_remove_hop_by_hop(&request->header);
if (code != 0) {
if (o.verbose)
logdebug("Error removing hop-by-hop headers.\n");
return code;
}
/* Build the Host header. */
if (request->uri.port == -1 || request->uri.port == 80)
n = Snprintf(buf, sizeof(buf), "%s", request->uri.host);
else
n = Snprintf(buf, sizeof(buf), "%s:%hu", request->uri.host, request->uri.port);
if (n < 0 || n >= sizeof(buf)) {
/* Request Entity Too Large. */
return 501;
}
request->header = http_header_set(request->header, "Host", buf);
request->header = http_header_set(request->header, "Connection", "close");
/* Send the request to the server. */
request_str = http_request_to_string(request, &len);
n = send(server_sock->fdn.fd, request_str, len, 0);
free(request_str);
if (n < 0)
return 504;
/* Send the request body, if any. Count up to Content-Length. */
while (request->bytes_transferred < request->content_length) {
n = socket_buffer_read(client_sock, buf, MIN(sizeof(buf), request->content_length - request->bytes_transferred));
if (n < 0)
return 504;
if (n == 0)
break;
request->bytes_transferred += n;
n = send(server_sock->fdn.fd, buf, n, 0);
if (n < 0)
return 504;
}
if (o.debug && request->bytes_transferred < request->content_length)
logdebug("Received only %lu request body bytes (Content-Length was %lu).\n", request->bytes_transferred, request->content_length);
/* Read the response. */
code = http_read_status_line(server_sock, &line);
if (o.debug > 1)
logdebug("Status-Line: %s", line);
if (code != 0) {
if (o.verbose)
logdebug("Error reading Status-Line.\n");
return 0;
}
code = http_parse_status_line(line, &response);
free(line);
if (code != 0) {
if (o.verbose)
logdebug("Error parsing Status-Line.\n");
return 0;
}
code = http_read_header(server_sock, &line);
if (code != 0) {
if (o.verbose)
logdebug("Error reading header.\n");
return 0;
}
if (o.debug > 1)
logdebug("Response header:\n%s", line);
code = http_response_parse_header(&response, line);
free(line);
if (code != 0) {
if (o.verbose)
logdebug("Error parsing response header.\n");
return 0;
}
/* The version we use to talk to the client. */
response.version = HTTP_10;
/* Remove headers that only apply to our connection with the server. */
code = http_header_remove_hop_by_hop(&response.header);
if (code != 0) {
if (o.verbose)
logdebug("Error removing hop-by-hop headers.\n");
return code;
}
response.header = http_header_set(response.header, "Connection", "close");
/* Send the response to the client. */
response_str = http_response_to_string(&response, &len);
n = fdinfo_send(&client_sock->fdn, response_str, len);
free(response_str);
if (n < 0) {
http_response_free(&response);
return 504;
}
/* If the Content-Length is 0, read until the connection is closed.
Otherwise read until the Content-Length. At this point it's too late to
return our own error code so return 0 in case of any error. */
while (response.content_length == 0
|| response.bytes_transferred < response.content_length) {
size_t remaining = response.content_length - response.bytes_transferred;
size_t count;
count = sizeof(buf);
if (response.content_length > 0 && remaining < count)
count = remaining;
n = socket_buffer_read(server_sock, buf, count);
if (n <= 0)
break;
response.bytes_transferred += n;
n = fdinfo_send(&client_sock->fdn, buf, n);
if (n < 0)
break;
}
http_response_free(&response);
return 0;
}
