X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=net.c;h=a5013b16c08b94510ad6acc8c69888b0444bac3f;hp=6a8eea3b261c3dadb8df2c73d25626150cd5ad00;hb=e1890028c21d233087266fd7997d68a88cb9afce;hpb=6703c9a063a61320294aa2cc519a911a4e76d49b diff --git a/net.c b/net.c index 6a8eea3b..a5013b16 100644 --- a/net.c +++ b/net.c @@ -1,51 +1,43 @@ /* * Copyright (C) 2005-2007 Andre Noll * - * 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 */ +/** \file net.c Networking-related helper functions. */ + +#include /* hostent */ #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 + * 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) @@ -64,9 +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(). */ @@ -81,16 +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; @@ -105,51 +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) { - int total = 0; /* how many bytes we've sent */ - int 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) { @@ -162,7 +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); @@ -172,14 +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) { @@ -188,12 +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, ...) { @@ -207,24 +191,22 @@ __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) */ -__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 (fd + 1 <= cda_size) @@ -233,34 +215,38 @@ __must_check int recv_bin_buffer(int fd, char *buf, ssize_t size) unsigned char *tmp = para_malloc(size); void *private = crypt_data_array[fd].private_data; n = recv(fd, tmp, size, 0); - if (n > 0) - (*cf)(n, tmp, (unsigned char *)buf, private); + 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); 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() */ -int recv_buffer(int fd, char *buf, ssize_t size) +int recv_buffer(int fd, char *buf, size_t size) { int n; + assert(size); n = recv_bin_buffer(fd, buf, size - 1); if (n >= 0) buf[n] = '\0'; @@ -270,73 +256,67 @@ int recv_buffer(int fd, char *buf, ssize_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_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) + * Wrapper around the accept system call. * - * \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 - * - * \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). */ @@ -347,7 +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) @@ -382,11 +362,11 @@ int init_unix_addr(struct sockaddr_un *u, const char *name) } /** - * 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. @@ -397,22 +377,27 @@ int init_unix_addr(struct sockaddr_un *u, const char *name) * \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 @@ -432,7 +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) @@ -471,7 +456,7 @@ ssize_t send_cred_buffer(int sock, char *buf) return ret; } -static void dispose_fds(int *fds, int num) +static void dispose_fds(int *fds, unsigned num) { int i; @@ -543,7 +528,7 @@ int recv_cred_buffer(int fd, char *buf, size_t size) * \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) @@ -551,7 +536,7 @@ int recv_cred_buffer(int fd, char *buf, size_t size) 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;