/*
- * Copyright (C) 2005-2006 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005-2007 Andre Noll <maan@systemlinux.org>
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
+ * Licensed under the GPL v2. For licencing details see COPYING.
*/
/** \file net.c networking-related helper functions */
#include "para.h"
+#include "error.h"
#include "net.h"
#include "string.h"
-#include <netdb.h>
-#include "error.h"
-
-extern void (*crypt_function_recv)(unsigned long len, const unsigned char *indata, unsigned char *outdata);
-extern void (*crypt_function_send)(unsigned long len, const unsigned char *indata, unsigned char *outdata);
-#ifndef HAVE_UCRED
- struct ucred {
- uid_t uid, pid, gid;
+/** Information about one encrypted connection. */
+struct crypt_data {
+ /** Function used to decrypt received data. */
+ crypt_function *recv;
+ /** Function used to encrypt data to be sent. */
+ crypt_function *send;
+ /**
+ * Context-dependent data (crypt keys), passed verbatim to the above
+ * crypt functions.
+ */
+ void *private_data;
};
-#endif /* HAVE_UCRED */
+/** Array holding per fd crypt data. */
+static struct crypt_data *crypt_data_array;
+/** Current size of the crypt data array. */
+static unsigned cda_size = 0;
+
+/**
+ * activate encryption for one file descriptor
+ *
+ * \param fd the file descriptor
+ * \param recv_f the function used for decrypting received data
+ * \param send_f the function used for encrypting before sending
+ * \param private_data user data supplied by the caller
+ */
+void enable_crypt(int fd, crypt_function *recv_f, crypt_function *send_f,
+ void *private_data)
+{
+ if (fd + 1 > cda_size) {
+ crypt_data_array = para_realloc(crypt_data_array,
+ (fd + 1) * sizeof(struct crypt_data));
+ memset(crypt_data_array + cda_size, 0,
+ (fd + 1 - cda_size) * sizeof(struct crypt_data));
+ cda_size = fd + 1;
+ }
+ crypt_data_array[fd].recv = recv_f;
+ crypt_data_array[fd].send = send_f;
+ crypt_data_array[fd].private_data = private_data;
+ PARA_INFO_LOG("rc4 encryption activated for fd %d\n", fd);
+}
+
+/**
+ * deactivate encryption for a given fd
+ *
+ * \param fd the file descriptor
+ *
+ * This must be called if and only if \p fd was activated via enable_crypt().
+ */
+void disable_crypt(int fd)
+{
+ if (cda_size < fd + 1)
+ return;
+ crypt_data_array[fd].recv = NULL;
+ crypt_data_array[fd].send = NULL;
+ crypt_data_array[fd].private_data = NULL;
+}
+
/**
* initialize a struct sockaddr_in
- * @param addr A pointer to the struct to be initialized
- * @param port The port number to use
- * @param he The address to use
*
- * If \a he is null (server mode), \a addr->sin_addr is initialized with \p INADDR_ANY.
- * Otherwise, the address given by \a he is copied to addr.
+ * \param addr A pointer to the struct to be initialized
+ * \param port The port number to use
+ * \param he The address to use
+ *
+ * If \a he is null (server mode), \a addr->sin_addr is initialized with \p
+ * INADDR_ANY. Otherwise, the address given by \a he is copied to addr.
*/
void init_sockaddr(struct sockaddr_in *addr, int port, const struct hostent *he)
{
/*
* send out a buffer, resend on short writes
- * @param fd the file descriptor
- * @param buf The buffer to be sent
- * @len The length of \a buf
+ *
+ * \param fd the file descriptor
+ * \param buf The buffer to be sent
+ * \param len The length of \a buf
*
* Due to circumstances beyond your control, the kernel might not send all the
* data out in one chunk, and now, my friend, it's up to us to get the data out
* there (Beej's Guide to Network Programming).
+ *
+ * \return This function returns 1 on success and \a -E_SEND on errors. The
+ * number of bytes actually sent is stored upon successful return in \a len.
*/
static int sendall(int fd, const char *buf, size_t *len)
{
- int total = 0; /* how many bytes we've sent */
- int bytesleft = *len; /* how many we have left to send */
+ size_t total = 0, bytesleft = *len; /* how many we have left to send */
int n = -1;
while (total < *len) {
}
/**
- * encrypt and send buffer
- * @param fd: the file descriptor
- * @param buf the buffer to be encrypted and sent
- * @param len the length of \a buf
+ * Encrypt and send a binary buffer.
+ *
+ * \param fd The file descriptor.
+ * \param buf The buffer to be encrypted and sent.
+ * \param len The length of \a buf.
*
- * Check if encrytion is available. If yes, encrypt the given buffer. Send out
- * the buffer, encrypted or not, and try to resend the remaing part in case of
- * short writes.
+ * Check if encryption is available. If yes, encrypt the given buffer. Send
+ * out the buffer, encrypted or not, and try to resend the remaing part in case
+ * of short writes.
*
- * @return Positive on success, \p -E_SEND on errors.
+ * \return Positive on success, \p -E_SEND on errors.
*/
int send_bin_buffer(int fd, const char *buf, size_t len)
{
int ret;
+ crypt_function *cf = NULL;
if (!len)
PARA_CRIT_LOG("%s", "len == 0\n");
- if (crypt_function_send) {
- unsigned char *outbuf = para_malloc(len);
- crypt_function_send(len, (unsigned char *)buf, outbuf);
+ if (fd + 1 <= cda_size)
+ cf = crypt_data_array[fd].send;
+ if (cf) {
+ void *private = crypt_data_array[fd].private_data;
+ /* RC4 may write more than len to the output buffer */
+ unsigned char *outbuf = para_malloc(ROUND_UP(len, 8));
+ (*cf)(len, (unsigned char *)buf, outbuf, private);
ret = sendall(fd, (char *)outbuf, &len);
free(outbuf);
} else
/**
* encrypt and send null terminated buffer.
- * @param fd the file descriptor
- * @param buf the null-terminated buffer to be send
+ *
+ * \param fd the file descriptor
+ * \param buf the null-terminated buffer to be send
*
* This is equivalent to send_bin_buffer(fd, buf, strlen(buf)).
*
- * @return Positive on success, \p -E_SEND on errors.
+ * \return Positive on success, \p -E_SEND on errors.
*/
int send_buffer(int fd, const char *buf)
{
/**
* send and encrypt a buffer given by a format string
- * @param fd the file descriptor
- * @param fmt a format string
*
- * @return Positive on success, \p -E_SEND on errors.
+ * \param fd the file descriptor
+ * \param fmt a format string
+ *
+ * \return Positive on success, \p -E_SEND on errors.
*/
__printf_2_3 int send_va_buffer(int fd, const char *fmt, ...)
{
/**
* receive and decrypt.
*
- * @param fd the file descriptor
- * @param buf the buffer to write the decrypted data to
- * @param size the size of @param buf
+ * \param fd the file descriptor
+ * \param buf the buffer to write the decrypted data to
+ * \param size the size of \a buf
*
- * Receive at most \a size bytes from filedescriptor fd. If encrytion is
+ * Receive at most \a size bytes from filedescriptor fd. If encryption is
* available, decrypt the received buffer.
*
- * @return the number of bytes received on success. On receive errors, -E_RECV
+ * \return The number of bytes received on success. On receive errors, -E_RECV
* is returned. On crypt errors, the corresponding crypt error number is
* returned.
+ *
* \sa recv(2)
*/
-__must_check int recv_bin_buffer(int fd, char *buf, ssize_t size)
+__must_check int recv_bin_buffer(int fd, char *buf, size_t size)
{
- int n;
+ ssize_t n;
+ crypt_function *cf = NULL;
- if (crypt_function_recv) {
+ if (fd + 1 <= cda_size)
+ cf = crypt_data_array[fd].recv;
+ if (cf) {
unsigned char *tmp = para_malloc(size);
+ void *private = crypt_data_array[fd].private_data;
n = recv(fd, tmp, size, 0);
- if (n > 0)
- crypt_function_recv(n, tmp, (unsigned char *)buf);
+ if (n > 0) {
+ size_t numbytes = n;
+ unsigned char *b = (unsigned char *)buf;
+ (*cf)(numbytes, tmp, b, private);
+ }
free(tmp);
} else
n = recv(fd, buf, size, 0);
/**
* receive, decrypt and write terminating NULL byte
*
- * @param fd the file descriptor
- * @param buf the buffer to write the decrypted data to
- * @param size the size of \a buf
+ * \param fd the file descriptor
+ * \param buf the buffer to write the decrypted data to
+ * \param size the size of \a buf
+ *
+ * Read and decrypt at most \a size - 1 bytes from file descriptor \a fd and
+ * write a NULL byte at the end of the received data.
*
- * Read and decrypt at most size - 1 bytes from file descriptor \a fd and write
- * a NULL byte at the end of the received data.
+ * \return: The return value of the underlying call to \a recv_bin_buffer().
*
-*/
-int recv_buffer(int fd, char *buf, ssize_t size)
+ * \sa recv_bin_buffer()
+ */
+int recv_buffer(int fd, char *buf, size_t size)
{
int n;
- if ((n = recv_bin_buffer(fd, buf, size - 1)) >= 0)
+ if (!size)
+ return -E_RECV;
+ n = recv_bin_buffer(fd, buf, size - 1);
+ if (n >= 0)
buf[n] = '\0';
+ else
+ *buf = '\0';
return n;
}
/**
* wrapper around gethostbyname
*
- * @param host hostname or IPv4 address
- * \return The hostent structure or a NULL pointer if an error occurs
+ * \param host hostname or IPv4 address
+ * \param ret the hostent structure is returned here
+ *
+ * \return positive on success, negative on errors. On success, \a ret
+ * contains the return value of the underlying gethostbyname() call.
+ *
* \sa gethostbyname(2)
*/
-struct hostent *get_host_info(char *host)
+int get_host_info(char *host, struct hostent **ret)
{
PARA_INFO_LOG("getting host info of %s\n", host);
/* FIXME: gethostbyname() is obsolete */
- return gethostbyname(host);
+ *ret = gethostbyname(host);
+ return *ret? 1 : -E_HOST_INFO;
}
/**
- * a wrapper around socket(2)
+ * A wrapper around socket(2).
+ *
+ * \param domain The communication domain that selects the protocol family.
+ *
+ * \return The socket fd on success, -E_SOCKET on errors.
*
* Create an IPv4 socket for sequenced, reliable, two-way, connection-based
* byte streams.
*
- * @return The socket fd on success, -E_SOCKET on errors.
- * \sa socket(2)
+ * \sa socket(2).
*/
-int get_socket(void)
+int get_stream_socket(int domain)
{
int socket_fd;
- if ((socket_fd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
+ if ((socket_fd = socket(domain, SOCK_STREAM, 0)) == -1)
return -E_SOCKET;
return socket_fd;
}
/**
- * a wrapper around connect(2)
+ * paraslash's wrapper around the accept system call
*
- * @param fd the file descriptor
- * @param their_addr the address to connect
+ * \param fd the listening socket
+ * \param addr structure which is filled in with the address of the peer socket
+ * \param size should contain the size of the structure pointed to by \a addr
*
- * @return \p -E_CONNECT on errors, 1 on success
- * \sa connect(2)
- */
-int para_connect(int fd, struct sockaddr_in *their_addr)
-{
- int ret;
-
- if ((ret = connect(fd, (struct sockaddr *)their_addr,
- sizeof(struct sockaddr))) == -1)
- return -E_CONNECT;
- return 1;
-}
-
-/**
- * paraslash's wrapper around the accept system call
+ * Accept incoming connections on \a addr. Retry if interrupted.
*
- * @param fd the listening socket
- * @param addr structure which is filled in with the address of the peer socket
- * @param size should contain the size of the structure pointed to by \a addr
+ * \return The new file descriptor on success, \a -E_ACCEPT on errors.
*
* \sa accept(2).
*/
{
int new_fd;
- new_fd = accept(fd, (struct sockaddr *) addr, &size);
- return new_fd == -1? -E_ACCEPT : new_fd;
+ do
+ new_fd = accept(fd, (struct sockaddr *) addr, &size);
+ while (new_fd < 0 && errno == EINTR);
+ return new_fd < 0? -E_ACCEPT : new_fd;
}
static int setserversockopts(int socket_fd)
return 1;
}
-static int do_bind(int socket_fd, struct sockaddr_in *my_addr)
-{
- if (bind(socket_fd, (struct sockaddr *)my_addr,
- sizeof(struct sockaddr)) == -1)
- return -E_BIND;
- return 1;
-}
-
/**
* prepare a structure for \p AF_UNIX socket addresses
*
}
/**
- * prepare, create, and bind and socket for local communication
+ * Prepare, create, and bind a socket for local communication.
*
- * \param name the socket pathname
- * \param unix_addr pointer to the \p AF_UNIX socket structure
- * \param mode the desired mode of the socket
+ * \param name The socket pathname.
+ * \param unix_addr Pointer to the \p AF_UNIX socket structure.
+ * \param mode The desired mode of the socket.
*
* This functions creates a local socket for sequenced, reliable,
* two-way, connection-based byte streams.
+ *
+ * \return The file descriptor, on success, negative on errors.
+ *
* \sa socket(2)
* \sa bind(2)
* \sa chmod(2)
*/
-int create_pf_socket(const char *name, struct sockaddr_un *unix_addr, int mode)
+int create_local_socket(const char *name, struct sockaddr_un *unix_addr,
+ mode_t mode)
{
int fd, ret;
- fd = socket(PF_UNIX, SOCK_STREAM, 0);
- if (fd < 0)
- return -E_SOCKET;
-// unlink(name);
ret = init_unix_addr(unix_addr, name);
if (ret < 0)
return ret;
+ fd = socket(PF_UNIX, SOCK_STREAM, 0);
+ if (fd < 0)
+ return -E_SOCKET;
+ ret = -E_BIND;
if (bind(fd, (struct sockaddr *) unix_addr, UNIX_PATH_MAX) < 0)
- return -E_BIND;
+ goto err;
+ ret = -E_CHMOD;
if (chmod(name, mode) < 0)
- return -E_CHMOD;
+ goto err;
return fd;
+err:
+ close(fd);
+ return ret;
}
+#ifndef HAVE_UCRED
+ssize_t send_cred_buffer(int sock, char *buf)
+{
+ return send_buffer(sock, buf);
+}
+int recv_cred_buffer(int fd, char *buf, size_t size)
+{
+ return recv_buffer(fd, buf, size) > 0? 1 : -E_RECVMSG;
+}
+#else /* HAVE_UCRED */
/**
* send NULL terminated buffer and Unix credentials of the current process
*
*
* \return On success, this call returns the number of characters sent. On
* error, \p -E_SENDMSG ist returned.
+ *
* \sa okir's Black Hats Manual
* \sa sendmsg(2)
*/
msg.msg_iovlen = 1;
msg.msg_control = control;
msg.msg_controllen = sizeof(control);
-#ifdef HAVE_UCRED
/* attach the ucred struct */
cmsg = CMSG_FIRSTHDR(&msg);
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_len = CMSG_LEN(sizeof(struct ucred));
*(struct ucred *)CMSG_DATA(cmsg) = c;
msg.msg_controllen = cmsg->cmsg_len;
-#endif
ret = sendmsg(sock, &msg, 0);
if (ret < 0)
ret = -E_SENDMSG;
return ret;
}
-static void dispose_fds(int *fds, int num)
+static void dispose_fds(int *fds, unsigned num)
{
int i;
int yes = 1;
struct ucred cred;
-#ifdef HAVE_UCRED
setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &yes, sizeof(int));
-#endif
memset(&msg, 0, sizeof(msg));
memset(buf, 0, size);
iov.iov_base = buf;
msg.msg_controllen = sizeof(control);
if (recvmsg(fd, &msg, 0) < 0)
return -E_RECVMSG;
-#ifdef HAVE_UCRED
result = -E_SCM_CREDENTIALS;
cmsg = CMSG_FIRSTHDR(&msg);
while (cmsg) {
}
cmsg = CMSG_NXTHDR(&msg, cmsg);
}
-#endif
return result;
}
+#endif /* HAVE_UCRED */
/** how many pending connections queue will hold */
#define BACKLOG 10
/**
* create a socket, bind it and listen
+ *
* \param port the tcp port to listen on
*
* \return The file descriptor of the created socket, negative
* on errors.
*
- * \sa get_socket()
+ * \sa get_stream_socket()
* \sa setsockopt(2)
* \sa bind(2)
* \sa listen(2)
*/
int init_tcp_socket(int port)
{
- int sockfd, ret;
struct sockaddr_in my_addr;
+ int fd, ret = get_stream_socket(AF_INET);
- if ((sockfd = get_socket()) < 0)
- return sockfd;
- ret = setserversockopts(sockfd);
if (ret < 0)
return ret;
- init_sockaddr(&my_addr, port, NULL);
- ret = do_bind(sockfd, &my_addr);
+ fd = ret;
+ ret = setserversockopts(fd);
if (ret < 0)
- return ret;
- if (listen(sockfd, BACKLOG) == -1)
- return -E_LISTEN;
- PARA_INFO_LOG("listening on port %d, fd %d\n", port, sockfd);
- return sockfd;
+ goto err;
+ init_sockaddr(&my_addr, port, NULL);
+ ret = -E_BIND;
+ if (bind(fd, (struct sockaddr *)&my_addr,
+ sizeof(struct sockaddr)) == -1) {
+ PARA_CRIT_LOG("bind error: %s\n", strerror(errno));
+ goto err;
+ }
+ ret = -E_LISTEN;
+ if (listen(fd, BACKLOG) == -1)
+ goto err;
+ PARA_INFO_LOG("listening on port %d, fd %d\n", port, fd);
+ return fd;
+err:
+ close(fd);
+ return ret;
}
/**
* to receive at most \a bufsize bytes from file descriptor \a fd.
* If at least \p strlen(\a pattern) bytes were received, the beginning of
* the received buffer is compared with \a pattern, ignoring case.
+ *
* \sa recv_buffer()
* \sa strncasecmp(3)
*/
goto out;
ret = 1;
out:
+ if (ret < 0) {
+ PARA_NOTICE_LOG("n = %d, did not receive pattern '%s'\n", n, pattern);
+ if (n > 0)
+ PARA_NOTICE_LOG("recvd: %s\n", buf);
+ }
free(buf);
- if (ret < 0)
- PARA_NOTICE_LOG("did not receive pattern '%s'\n", buf);
return ret;
}