X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=net.c;h=a5013b16c08b94510ad6acc8c69888b0444bac3f;hp=c5f33c822164195615d7f8f318f22a3f1d43a79f;hb=e1890028c21d233087266fd7997d68a88cb9afce;hpb=8211954fc3390c0fa19cca788b03336a37aa9dc0 diff --git a/net.c b/net.c index c5f33c82..a5013b16 100644 --- a/net.c +++ b/net.c @@ -4,12 +4,14 @@ * Licensed under the GPL v2. For licencing details see COPYING. */ -/** \file net.c networking-related helper functions */ +/** \file net.c Networking-related helper functions. */ + +#include /* hostent */ #include "para.h" +#include "error.h" #include "net.h" #include "string.h" -#include "error.h" /** Information about one encrypted connection. */ @@ -30,12 +32,12 @@ static struct crypt_data *crypt_data_array; static unsigned cda_size = 0; /** - * activate encryption for one file descriptor + * 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 + * \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) @@ -54,9 +56,9 @@ void enable_crypt(int fd, crypt_function *recv_f, crypt_function *send_f, } /** - * deactivate encryption for a given fd + * Deactivate encryption for a given fd. * - * \param fd the file descriptor + * \param fd The file descriptor. * * This must be called if and only if \p fd was activated via enable_crypt(). */ @@ -71,16 +73,16 @@ void disable_crypt(int fd) /** - * initialize a struct sockaddr_in + * 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 + * \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) +static void init_sockaddr(struct sockaddr_in *addr, int port, const struct hostent *he) { /* host byte order */ addr->sin_family = AF_INET; @@ -95,50 +97,42 @@ 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 - * \param len The length of \a buf + * Send out a buffer, resend on short writes. * - * 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). + * \param fd The file descriptor. + * \param buf The buffer to be sent. + * \param len The length of \a buf. * - * \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) { @@ -151,7 +145,8 @@ 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); @@ -161,14 +156,14 @@ int send_bin_buffer(int fd, const char *buf, size_t len) } /** - * 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) { @@ -177,12 +172,12 @@ 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, ...) { @@ -196,18 +191,16 @@ __printf_2_3 int send_va_buffer(int fd, const char *fmt, ...) } /** - * receive and decrypt. + * Receive and decrypt. * - * \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. * - * 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) */ @@ -231,21 +224,21 @@ __must_check int recv_bin_buffer(int fd, char *buf, size_t size) } else n = recv(fd, buf, size, 0); if (n == -1) - n = -E_RECV; + return -ERRNO_TO_PARA_ERROR(errno); return n; } /** - * receive, decrypt and write terminating NULL byte + * 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. * - * \return: The return value of the underlying call to \a recv_bin_buffer(). + * \return The return value of the underlying call to \a recv_bin_buffer(). * * \sa recv_bin_buffer() */ @@ -253,8 +246,7 @@ int recv_buffer(int fd, char *buf, size_t size) { int n; - if (!size) - return -E_RECV; + assert(size); n = recv_bin_buffer(fd, buf, size - 1); if (n >= 0) buf[n] = '\0'; @@ -264,33 +256,47 @@ int recv_buffer(int fd, char *buf, size_t size) } /** - * wrapper around gethostbyname - * - * \param host hostname or IPv4 address - * \param ret the hostent structure is returned here + * Establish a tcp connection. * - * \return positive on success, negative on errors. On success, \a ret - * contains the return value of the underlying gethostbyname() call. + * \param host Hostname or IPv4 address. + * \param port The tcp port. * - * \sa gethostbyname(2) + * \return Negative on errors, a valid file descriptor on success. */ -int get_host_info(char *host, struct hostent **ret) +int tcp_connect(char *host, int port) { + struct sockaddr_in addr; + struct hostent *he; + int ret, fd; + PARA_INFO_LOG("getting host info of %s\n", host); /* FIXME: gethostbyname() is obsolete */ - *ret = gethostbyname(host); - return *ret? 1 : -E_HOST_INFO; + he = gethostbyname(host); + if (!he) + return -ERRNO_TO_PARA_ERROR(h_errno); + init_sockaddr(&addr, port, he); + ret = get_stream_socket(AF_INET); + if (ret < 0) + return ret; + fd = ret; + ret = PARA_CONNECT(fd, &addr); + if (ret >= 0) + return fd; + close(fd); + return ret; } /** - * 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_stream_socket(int domain) { @@ -302,35 +308,15 @@ int get_stream_socket(int domain) } /** - * 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 + * Wrapper around the accept system call. * - * \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 + * \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. * * Accept incoming connections on \a addr. Retry if interrupted. * - * \return The new file descriptor on success, \a -E_ACCEPT on errors. + * \return The new file descriptor on success, negative on errors. * * \sa accept(2). */ @@ -341,7 +327,7 @@ int para_accept(int fd, void *addr, socklen_t size) do new_fd = accept(fd, (struct sockaddr *) addr, &size); while (new_fd < 0 && errno == EINTR); - return new_fd < 0? -E_ACCEPT : new_fd; + return new_fd < 0? -ERRNO_TO_PARA_ERROR(errno) : new_fd; } static int setserversockopts(int socket_fd) @@ -431,7 +417,7 @@ int recv_cred_buffer(int fd, char *buf, size_t size) * \param buf the buffer to be sent * * \return On success, this call returns the number of characters sent. On - * error, \p -E_SENDMSG ist returned. + * error, \p -E_SENDMSG is returned. * * \sa okir's Black Hats Manual * \sa sendmsg(2)