X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=net.c;h=0105ef6902114ae108da577186c1d58d8e52c0fb;hp=59b8616a56be2cd0dec066a5c431d3fbea9cab43;hb=17cba74507aad9a2cf5a8f113270e4bf6f8ade40;hpb=2ed89c59f0efcd0a2763f47c7d3455663241e623 diff --git a/net.c b/net.c index 59b8616a..0105ef69 100644 --- a/net.c +++ b/net.c @@ -20,13 +20,61 @@ #include "para.h" #include "net.h" -#include "gcc-compat.h" -#include -#include "error.h" #include "string.h" +#include "error.h" + + +/** \cond holds information about one encrypted connection */ +struct crypt_data { + crypt_function *recv; + crypt_function *send; + void *private_data; +}; +static unsigned cda_size = 0; +static struct crypt_data *crypt_data_array; +/** \endcond */ + + +/** + * 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; +} -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); /** * initialize a struct sockaddr_in @@ -74,7 +122,7 @@ static int sendall(int fd, const char *buf, size_t *len) total += n; bytesleft -= n; if (total < *len) - PARA_DEBUG_LOG("short write (%d byte(s) left)", + PARA_DEBUG_LOG("short write (%zd byte(s) left)", *len - total); } *len = total; /* return number actually sent here */ @@ -87,7 +135,7 @@ static int sendall(int fd, const char *buf, size_t *len) * @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 + * 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. * @@ -96,12 +144,16 @@ static int sendall(int fd, const char *buf, size_t *len) 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) { + if (fd + 1 <= cda_size) + cf = crypt_data_array[fd].send; + if (cf) { + void *private = crypt_data_array[fd].private_data; unsigned char *outbuf = para_malloc(len); - crypt_function_send(len, (unsigned char *)buf, outbuf); + (*cf)(len, (unsigned char *)buf, outbuf, private); ret = sendall(fd, (char *)outbuf, &len); free(outbuf); } else @@ -131,7 +183,7 @@ int send_buffer(int fd, const char *buf) * * @return Positive on success, \p -E_SEND on errors. */ -__printf_2_3 int send_va_buffer(int fd, char *fmt, ...) +__printf_2_3 int send_va_buffer(int fd, const char *fmt, ...) { char *msg; int ret; @@ -149,7 +201,7 @@ __printf_2_3 int send_va_buffer(int fd, char *fmt, ...) * @param buf the buffer to write the decrypted data to * @param size the size of @param 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 @@ -160,12 +212,16 @@ __printf_2_3 int send_va_buffer(int fd, char *fmt, ...) __must_check int recv_bin_buffer(int fd, char *buf, ssize_t size) { int 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); + (*cf)(n, tmp, (unsigned char *)buf, private); free(tmp); } else n = recv(fd, buf, size, 0); @@ -189,23 +245,31 @@ int recv_buffer(int fd, char *buf, ssize_t size) { int n; - if ((n = recv_bin_buffer(fd, buf, size - 1)) >= 0) + 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; } /** @@ -248,18 +312,20 @@ int para_connect(int fd, struct sockaddr_in *their_addr) /** * 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 * * \sa accept(2). */ -int para_accept(int fd, void *addr, size_t size) +int para_accept(int fd, void *addr, socklen_t size) { 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) @@ -272,14 +338,6 @@ 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 * @@ -332,6 +390,16 @@ int create_pf_socket(const char *name, struct sockaddr_un *unix_addr, int mode) return fd; } +#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 * @@ -391,19 +459,21 @@ static void dispose_fds(int *fds, int num) * \param fd the socket file descriptor * \param buf the buffer to store the message * \param size the size of \a buffer - * \param cred the credentials are returned here + * + * \return negative on errors, the user id on success. * * \sa okir's Black Hats Manual * \sa recvmsg(2) */ -int recv_cred_buffer(int fd, char *buf, size_t size, struct ucred *cred) +int recv_cred_buffer(int fd, char *buf, size_t size) { char control[255]; struct msghdr msg; struct cmsghdr *cmsg; struct iovec iov; - int result; + int result = 0; int yes = 1; + struct ucred cred; setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &yes, sizeof(int)); memset(&msg, 0, sizeof(msg)); @@ -416,13 +486,13 @@ int recv_cred_buffer(int fd, char *buf, size_t size, struct ucred *cred) msg.msg_controllen = sizeof(control); if (recvmsg(fd, &msg, 0) < 0) return -E_RECVMSG; - result = -SCM_CREDENTIALS; + result = -E_SCM_CREDENTIALS; cmsg = CMSG_FIRSTHDR(&msg); while (cmsg) { if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_CREDENTIALS) { - memcpy(cred, CMSG_DATA(cmsg), sizeof(struct ucred)); - result = iov.iov_len; + memcpy(&cred, CMSG_DATA(cmsg), sizeof(struct ucred)); + result = cred.uid; } else if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) { @@ -434,6 +504,7 @@ int recv_cred_buffer(int fd, char *buf, size_t size, struct ucred *cred) } return result; } +#endif /* HAVE_UCRED */ /** how many pending connections queue will hold */ #define BACKLOG 10 @@ -445,29 +516,37 @@ int recv_cred_buffer(int fd, char *buf, size_t size, struct ucred *cred) * \return The file descriptor of the created socket, negative * on errors. * - * \sa get_socket() + * \sa get_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_socket(); - 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; } /** @@ -494,11 +573,15 @@ int recv_pattern(int fd, const char *pattern, size_t bufsize) if (n < len) goto out; - buf[n] = '\0'; if (strncasecmp(buf, pattern, len)) 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); return ret; }