/** \file net.c networking-related helper functions */
#include "para.h"
+#include "error.h"
#include "net.h"
#include "string.h"
-#include "error.h"
-/** holds information about one encrypted connection */
+/** Information about one encrypted connection. */
struct crypt_data {
- /** function used to decrypt received data */
+ /** Function used to decrypt received data. */
crypt_function *recv;
- /** function used to encrypt data to be sent */
+ /** Function used to encrypt data to be sent. */
crypt_function *send;
- /** context-dependent data, passed to \a recv() and \a send() */
+ /**
+ * Context-dependent data (crypt keys), passed verbatim to the above
+ * crypt functions.
+ */
void *private_data;
};
-/** array holding per fd crypt data per */
+/** Array holding per fd crypt data. */
static struct crypt_data *crypt_data_array;
-/** current size of the crypt data array */
+/** Current size of the crypt data array. */
static unsigned cda_size = 0;
-
/**
* activate encryption for one file descriptor
*
}
/*
- * send out a buffer, resend on short writes
+ * Send out a buffer, resend on short writes.
*
- * \param fd the file descriptor
- * \param buf The buffer to be sent
- * \param 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.
+ * \return Standard. In any case, the number of bytes actually sent is stored
+ * in \a len.
*/
static int sendall(int fd, const char *buf, size_t *len)
{
- size_t total = 0, bytesleft = *len; /* how many we have left to send */
- int n = -1;
-
- while (total < *len) {
- n = send(fd, buf + total, bytesleft, 0);
- if (n == -1)
- break;
- total += n;
- bytesleft -= n;
- if (total < *len)
- PARA_DEBUG_LOG("short write (%zd byte(s) left)",
- *len - total);
+ size_t total = *len;
+
+ assert(total);
+ *len = 0;
+ while (*len < total) {
+ int ret = send(fd, buf + *len, total - *len, 0);
+ if (ret == -1)
+ return -ERRNO_TO_PARA_ERROR(errno);
+ *len += ret;
}
- *len = total; /* return number actually sent here */
- return n == -1? -E_SEND : 1; /* return 1 on success */
+ return 1;
}
/**
- * encrypt and send buffer
+ * 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
+ * \param fd The file descriptor.
+ * \param buf The buffer to be encrypted and sent.
+ * \param len The length of \a buf.
*
- * Check if encrytpion 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 Standard.
*/
int send_bin_buffer(int fd, const char *buf, size_t len)
{
cf = crypt_data_array[fd].send;
if (cf) {
void *private = crypt_data_array[fd].private_data;
- unsigned char *outbuf = para_malloc(len);
+ /* 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);
}
/**
- * encrypt and send null terminated buffer.
+ * 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 Standard.
*/
int send_buffer(int fd, const char *buf)
{
/**
- * send and encrypt a buffer given by a format string
+ * Send and encrypt a buffer given by a format string.
*
- * \param fd the file descriptor
- * \param fmt a format string
+ * \param fd The file descriptor.
+ * \param fmt A format string.
*
- * \return Positive on success, \p -E_SEND on errors.
+ * \return Standard.
*/
__printf_2_3 int send_va_buffer(int fd, const char *fmt, ...)
{
* \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 encryption is
+ * Receive at most \a size bytes from file descriptor \a fd. If encryption is
* available, decrypt the received buffer.
*
- * \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.
+ * \return The number of bytes received on success, negative on errors.
*
* \sa recv(2)
*/
} else
n = recv(fd, buf, size, 0);
if (n == -1)
- n = -E_RECV;
+ return -ERRNO_TO_PARA_ERROR(errno);
return n;
}
{
int n;
- if (!size)
- return -E_RECV;
+ assert(size);
n = recv_bin_buffer(fd, buf, size - 1);
if (n >= 0)
buf[n] = '\0';
}
/**
- * a wrapper around socket(2)
+ * A wrapper around socket(2).
*
- * Create an IPv4 socket for sequenced, reliable, two-way, connection-based
- * byte streams.
+ * \param domain The communication domain that selects the protocol family.
*
* \return The socket fd on success, -E_SOCKET on errors.
*
- * \sa socket(2)
+ * Create an IPv4 socket for sequenced, reliable, two-way, connection-based
+ * byte streams.
+ *
+ * \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)
- *
- * \param fd the file descriptor
- * \param their_addr the address to connect
- *
- * \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
*
* \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)
{
struct sockaddr_in my_addr;
- int fd, ret = get_socket();
+ int fd, ret = get_stream_socket(AF_INET);
if (ret < 0)
return ret;