Massive changes. Split process_method() into a bunch of smaller files and

changed the parsing code from REGEX and uri.c to a simplier sscanf()
method. Also, include code to handle SSL connections, but that's not quite
working yet.
This commit is contained in:
Robert James Kaes 2001-09-14 04:56:29 +00:00
parent bce9e6601e
commit c6d2e0f7ff

View File

@ -1,4 +1,4 @@
/* $Id: reqs.c,v 1.23 2001-09-12 03:33:15 rjkaes Exp $
/* $Id: reqs.c,v 1.24 2001-09-14 04:56:29 rjkaes Exp $
*
* This is where all the work in tinyproxy is actually done. Incoming
* connections have a new thread created for them. The thread then
@ -34,22 +34,13 @@
#include "reqs.h"
#include "sock.h"
#include "stats.h"
#include "uri.h"
#include "utils.h"
#define HTTPPATTERN "^([a-z]+)[ \t]+([^ \t]+)([ \t]+(HTTP/[0-9]+\\.[0-9]+))?"
#define NMATCH 4
#define METHOD_IND 1
#define URI_IND 2
#define VERSION_MARK 3
#define VERSION_IND 4
#define HTTP400ERROR "Unrecognizable request. Only HTTP is allowed."
#define HTTP500ERROR "Unable to connect to remote server."
#define HTTP503ERROR "Internal server error."
#define LINE_LENGTH (MAXBUFFSIZE / 3)
#define HTTP_PORT 80
/*
* Write the buffer to the socket. If an EINTR occurs, pick up and try
@ -105,228 +96,322 @@ static inline void trim(char *string, unsigned int len)
}
/*
* Parse a client HTTP request and then establish connection.
* Read in the first line from the client (the request line for HTTP
* connections. The request line is allocated from the heap, but it must
* be freed in another function.
*/
static int process_method(struct conn_s *connptr)
static char *read_request_line(struct conn_s *connptr)
{
URI *uri = NULL;
char *inbuf;
char *buffer = NULL, *request = NULL, *port = NULL;
regex_t preg;
regmatch_t pmatch[NMATCH];
size_t request_len;
char *request_buffer;
size_t len;
int fd, port_no = HTTP_PORT;
char peer_ipaddr[PEER_IP_LENGTH];
getpeer_ip(connptr->client_fd, peer_ipaddr);
inbuf = safemalloc(LINE_LENGTH);
if (!inbuf) {
log_message(LOG_ERR, "Could not allocate memory in 'process_method'.");
return -2;
request_buffer = safemalloc(LINE_LENGTH);
if (!request_buffer) {
log_message(LOG_ERR, "Could not allocate memory in 'read_request_line'");
return NULL;
}
len = readline(connptr->client_fd, inbuf, LINE_LENGTH);
len = readline(connptr->client_fd, request_buffer, LINE_LENGTH);
if (len <= 0) {
log_message(LOG_ERR, "Client [%s] closed socket before read.", peer_ipaddr);
update_stats(STAT_BADCONN);
safefree(inbuf);
return -2;
log_message(LOG_ERR, "Client (file descriptor: %d) closed socket before read.", connptr->client_fd);
safefree(request_buffer);
return NULL;
}
/*
* Strip the newline and character return from the string.
* Strip the new line and character return from the string.
*/
trim(inbuf, len);
trim(request_buffer, len);
log_message(LOG_CONN, "Request: %s", inbuf);
log_message(LOG_CONN, "Request (file descriptor %d): %s",
connptr->client_fd, request_buffer);
if (regcomp(&preg, HTTPPATTERN, REG_EXTENDED | REG_ICASE) != 0) {
log_message(LOG_ERR, "Regular Expression compiling error.");
httperr(connptr, 503, HTTP503ERROR);
update_stats(STAT_BADCONN);
goto EARLY_EXIT;
}
if (regexec(&preg, inbuf, NMATCH, pmatch, 0) != 0) {
log_message(LOG_ERR, "Regular Expression search error.");
regfree(&preg);
httperr(connptr, 503, HTTP503ERROR);
update_stats(STAT_BADCONN);
goto EARLY_EXIT;
}
regfree(&preg);
return request_buffer;
}
/*
* Test for a simple request, or a request from version 0.9
* - rjkaes
*/
if (pmatch[VERSION_MARK].rm_so == -1
|| !strncasecmp("http/0.9", inbuf + pmatch[VERSION_IND].rm_so, 8))
connptr->simple_req = TRUE;
/*
* This structure holds the information pulled from a URL request.
*/
struct request_s {
char *host;
char *path;
int port;
};
/*
* Pull the information out of the URL line.
*/
static int extract_http_url(const char *url, struct request_s *request)
{
request->host = safemalloc(strlen(url) + 1);
request->path = safemalloc(strlen(url) + 1);
if (pmatch[METHOD_IND].rm_so == -1 || pmatch[URI_IND].rm_so == -1) {
log_message(LOG_ERR, "Incomplete request line from [%s].",
peer_ipaddr);
httperr(connptr, 400, HTTP400ERROR);
update_stats(STAT_BADCONN);
goto EARLY_EXIT;
if (!request->host || !request->path) {
log_message(LOG_ERR, "Could not allocate memory in 'extract_http_url'");
safefree(request->host);
safefree(request->path);
return -1;
}
len = pmatch[URI_IND].rm_eo - pmatch[URI_IND].rm_so;
if (!(buffer = safemalloc(len + 1))) {
log_message(LOG_ERR,
"Could not allocate memory for request from [%s].",
peer_ipaddr);
httperr(connptr, 503, HTTP503ERROR);
update_stats(STAT_BADCONN);
goto EARLY_EXIT;
}
memcpy(buffer, inbuf + pmatch[URI_IND].rm_so, len);
buffer[len] = '\0';
if (!(uri = explode_uri(buffer))) {
safefree(buffer);
httperr(connptr, 503, HTTP503ERROR);
update_stats(STAT_BADCONN);
goto EARLY_EXIT;
}
safefree(buffer);
if (!uri->scheme || strcasecmp(uri->scheme, "http") != 0) {
char *error_string;
if (uri->scheme) {
size_t error_string_len = strlen(uri->scheme) + 64;
error_string = safemalloc(error_string_len);
if (!error_string) {
log_message(LOG_ERR,
"Could not allocate memory for request from [%s].",
peer_ipaddr);
goto COMMON_EXIT;
}
snprintf(error_string, error_string_len,
"Invalid scheme (%s). Only HTTP is allowed.",
uri->scheme);
} else {
error_string =
strdup("Invalid scheme (NULL). Only HTTP is allowed.");
if (!error_string) {
log_message(LOG_ERR,
"Could not allocate memory for request from [%s].",
peer_ipaddr);
goto COMMON_EXIT;
}
}
httperr(connptr, 400, error_string);
safefree(error_string);
update_stats(STAT_BADCONN);
goto COMMON_EXIT;
}
if (!uri->authority) {
httperr(connptr, 400, "Invalid authority.");
update_stats(STAT_BADCONN);
goto COMMON_EXIT;
}
if ((strlen(config.stathost) > 0) &&
strcasecmp(uri->authority, config.stathost) == 0) {
showstats(connptr);
goto COMMON_EXIT;
}
if ((port = strchr(uri->authority, ':'))) {
*port++ = '\0';
if (strlen(port) > 0)
port_no = atoi(port);
}
#ifdef FILTER_ENABLE
/* Filter domains out */
if (config.filter) {
if (filter_url(uri->authority)) {
log_message(LOG_ERR,
"Proxying refused on filtered domain \"%s\" from [%s].",
uri->authority,
peer_ipaddr);
httperr(connptr, 404,
"Connection to filtered domain is not allowed.");
update_stats(STAT_DENIED);
goto COMMON_EXIT;
}
}
#endif /* FILTER_ENABLE */
/* Build a new request from the first line of the header */
request_len = strlen(inbuf) + 1;
if (!(request = safemalloc(request_len))) {
log_message(LOG_ERR,
"Could not allocate memory for request from [%s].",
peer_ipaddr);
httperr(connptr, 503, HTTP503ERROR);
update_stats(STAT_BADCONN);
goto COMMON_EXIT;
}
memcpy(request, inbuf, pmatch[METHOD_IND].rm_eo);
request[pmatch[METHOD_IND].rm_eo] = '\0';
strlcat(request, " ", request_len);
if (strlen(uri->path) > 0) {
strlcat(request, uri->path, request_len);
if (uri->query) {
strlcat(request, "?", request_len);
strlcat(request, uri->query, request_len);
}
if (sscanf(url, "http://%[^:/]:%d%s", request->host, &request->port, request->path) == 3)
;
else if (sscanf(url, "http://%[^/]%s", request->host, request->path) == 2)
request->port = 80;
else if (sscanf(url, "http://%[^:/]:%d", request->host, &request->port) == 2)
strcpy(request->path, "/");
else if (sscanf(url, "http://%[^/]", request->host) == 1) {
request->port = 80;
strcpy(request->path, "/");
} else {
strlcat(request, "/", request_len);
}
strlcat(request, " HTTP/1.0\r\n", request_len);
log_message(LOG_ERR, "Can't parse URL.");
fd = opensock(uri->authority, port_no);
if (fd < 0) {
httperr(connptr, 500, HTTP500ERROR);
update_stats(STAT_DENIED);
goto COMMON_EXIT;
safefree(request->host);
safefree(request->path);
return -1;
}
connptr->server_fd = fd;
return 0;
}
if (safe_write(connptr->server_fd, request, strlen(request)) < 0)
goto COMMON_EXIT;
/*
* Extract the URL from a SSL connection.
*/
static int extract_ssl_url(const char *url, struct request_s *request)
{
request->host = safemalloc(strlen(url) + 1);
if (!request->host) {
log_message(LOG_ERR, "Could not allocate memory in 'extract_https_url'");
return -1;
}
if (sscanf(url, "%[^:]:%d", request->host, &request->port) == 2)
;
else if (sscanf(url, "%s", request->host) == 1)
request->port = 443;
else {
log_message(LOG_ERR, "Can't parse URL.");
safefree(request->host);
return -1;
}
return 0;
}
/*
* Create a connection for HTTP connections.
*/
static int establish_http_connection(struct conn_s *connptr,
const char *method,
const char *protocol,
struct request_s *request)
{
char *request_line;
size_t request_len;
request_len = strlen(method) + strlen(protocol) + strlen(request->path) + 13;
request_line = safemalloc(request_len);
if (!request_line) {
log_message(LOG_ERR, "Could not allocate memory in 'process_request'");
httperr(connptr, 503, HTTP503ERROR);
return -1;
}
strlcpy(request_line, method, request_len);
strlcat(request_line, " ", request_len);
strlcat(request_line, request->path, request_len);
strlcat(request_line, " ", request_len);
strlcat(request_line, "HTTP/1.0", request_len);
strlcat(request_line, "\r\n", request_len);
if (safe_write(connptr->server_fd, request_line, strlen(request_line)) < 0) {
safefree(request_line);
return -1;
}
safefree(request_line);
/*
* Send the Host: header
* Send headers
*/
if (safe_write(connptr->server_fd, "Host: ", 6) < 0)
goto COMMON_EXIT;
if (safe_write(connptr->server_fd, uri->authority, strlen(uri->authority)) < 0)
goto COMMON_EXIT;
if (safe_write(connptr->server_fd, "Host: ", 6) < 0) {
return -1;
}
if (safe_write(connptr->server_fd, request->host, strlen(request->host)) < 0) {
return -1;
}
if (safe_write(connptr->server_fd, "\r\n", 2) < 0)
goto COMMON_EXIT;
return -1;
/*
* Send the Connection header since we don't support persistant
* connections.
*/
if (safe_write(connptr->server_fd, "Connection: close\r\n", 19) < 0)
goto COMMON_EXIT;
return -1;
safefree(inbuf);
safefree(request);
free_uri(uri);
return 0;
}
COMMON_EXIT:
free_uri(uri);
/*
* Break the request line apart and figure out where to connect and
* build a new request line. Finally connect to the remote server.
*/
static int process_request(struct conn_s *connptr, char *request_line)
{
char *method;
char *url;
char *protocol;
EARLY_EXIT:
safefree(inbuf);
safefree(request);
return -1;
struct request_s request;
int ret;
size_t request_len;
/* NULL out all the fields so free's don't cause segfaults. */
memset(&request, 0, sizeof(struct request_s));
request_len = strlen(request_line) + 1;
method = safemalloc(request_len);
url = safemalloc(request_len);
protocol = safemalloc(request_len);
if (!method || !url || !protocol) {
log_message(LOG_ERR, "Could not allocate memory in 'process_request'");
safefree(method);
safefree(url);
safefree(protocol);
return -1;
}
ret = sscanf(request_line, "%[^ ] %[^ ] %[^ ]", method, url, protocol);
if (ret < 2) {
log_message(LOG_ERR, "Bad Request on file descriptor %d", connptr->client_fd);
httperr(connptr, 400, "Bad Request. No request found.");
safefree(method);
safefree(url);
safefree(protocol);
return -1;
} else if (ret == 2) {
connptr->simple_req = TRUE;
}
if (!url) {
log_message(LOG_ERR, "Null URL on file descriptor %d", connptr->client_fd);
httperr(connptr, 400, "Bad Request. Null URL.");
safefree(method);
safefree(url);
safefree(protocol);
return -1;
}
if (strncasecmp(url, "http://", 7) == 0) {
/* Make sure the first four characters are lowercase */
memcpy(url, "http", 4);
if (extract_http_url(url, &request) < 0) {
httperr(connptr, 400, "Bad Request. Could not parse URL.");
safefree(method);
safefree(url);
safefree(protocol);
return -1;
}
connptr->ssl = FALSE;
} else if (strcmp(method, "CONNECT") == 0) {
if (extract_ssl_url(url, &request) < 0) {
httperr(connptr, 400, "Bad Request. Could not parse URL.");
safefree(method);
safefree(url);
safefree(protocol);
return -1;
}
connptr->ssl = TRUE;
} else {
log_message(LOG_ERR, "Unknown URL type on file descriptor %d", connptr->client_fd);
httperr(connptr, 400, "Bad Request. Unknown URL type.");
safefree(method);
safefree(url);
safefree(protocol);
return -1;
}
safefree(url);
#ifdef FILTER_ENABLE
/*
* Filter restricted domains
*/
if (config.filter) {
if (filter_url(request.host)) {
log_message(LOG_ERR, "Proxying refused on filtered domain \"%s\"", request.host);
httperr(connptr, 404, "Connection to filtered domain is now allowed.");
safefree(request.host);
safefree(request.path);
safefree(method);
safefree(url);
return -1;
}
}
#endif
/*
* Connect to the remote server.
*/
connptr->server_fd = opensock(request.host, request.port);
if (connptr->server_fd < 0) {
httperr(connptr, 500, HTTP500ERROR);
safefree(request.host);
safefree(request.path);
safefree(method);
safefree(protocol);
return -1;
}
if (!connptr->ssl) {
if (establish_http_connection(connptr, method, protocol, &request) < 0) {
safefree(method);
safefree(protocol);
safefree(request.host);
safefree(request.path);
return -1;
}
}
safefree(method);
safefree(protocol);
safefree(request.host);
safefree(request.path);
return 0;
}
/*
@ -641,6 +726,8 @@ static void initialize_conn(struct conn_s *connptr)
connptr->output_message = NULL;
connptr->simple_req = FALSE;
connptr->ssl = FALSE;
update_stats(STAT_OPEN);
}
@ -677,7 +764,10 @@ void handle_connection(int fd)
char peer_ipaddr[PEER_IP_LENGTH];
char peer_string[PEER_STRING_LENGTH];
log_message(LOG_CONN, "Connect: %s [%s]",
char *request_line;
log_message(LOG_CONN, "Connect (file descriptor %d): %s [%s]",
fd,
getpeer_string(fd, peer_string),
getpeer_ip(fd, peer_ipaddr));
@ -726,13 +816,22 @@ void handle_connection(int fd)
#endif /* TUNNEL_SUPPORT */
internal_proxy:
if (process_method(connptr) < -1) {
request_line = read_request_line(connptr);
if (!request_line) {
destroy_conn(connptr);
return;
}
if (process_request(connptr, request_line) < 0) {
safefree(request_line);
destroy_conn(connptr);
return;
}
safefree(request_line);
send_error:
if (!connptr->simple_req) {
if (!connptr->simple_req && !connptr->ssl) {
if (process_client_headers(connptr) < 0) {
update_stats(STAT_BADCONN);
destroy_conn(connptr);
@ -748,10 +847,18 @@ send_error:
return;
}
if (process_server_headers(connptr) < 0) {
update_stats(STAT_BADCONN);
destroy_conn(connptr);
return;
if (!connptr->ssl) {
if (process_server_headers(connptr) < 0) {
update_stats(STAT_BADCONN);
destroy_conn(connptr);
return;
}
} else {
if (safe_write(connptr->client_fd, "HTTP/1.0 200 Connection established\r\n\r\n", 39) < 0) {
log_message(LOG_ERR, "Could not send SSL greeting to client.");
destroy_conn(connptr);
return;
}
}
relay_proxy: