From 5c306289b8a78a060a12eba5cd86e0efc3533da0 Mon Sep 17 00:00:00 2001 From: marc Date: Mon, 20 Mar 2000 06:03:29 +0000 Subject: reorganized tree after kernel merge --- libipq/libipq.c | 310 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 310 insertions(+) create mode 100644 libipq/libipq.c (limited to 'libipq/libipq.c') diff --git a/libipq/libipq.c b/libipq/libipq.c new file mode 100644 index 0000000..06e4a02 --- /dev/null +++ b/libipq/libipq.c @@ -0,0 +1,310 @@ +/* + * libipq.c + * + * IPQ userspace library. + * + * Please note that this library is still developmental, and there may + * be some API changes. + * + * 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. + * + */ + +#include +#include +#include +#include + +#include + +/**************************************************************************** + * + * Private interface + * + ****************************************************************************/ + +enum { + IPQ_ERR_NONE = 0, + IPQ_ERR_IMPL, + IPQ_ERR_HANDLE, + IPQ_ERR_SOCKET, + IPQ_ERR_BIND, + IPQ_ERR_BUFFER, + IPQ_ERR_RECV, + IPQ_ERR_NLEOF, + IPQ_ERR_ADDRLEN, + IPQ_ERR_STRUNC, + IPQ_ERR_RTRUNC, + IPQ_ERR_NLRECV, + IPQ_ERR_SEND, + IPQ_ERR_SUPP, + IPQ_ERR_RECVBUF +}; +#define IPQ_MAXERR IPQ_ERR_RECVBUF + +struct ipq_errmap_t { + int errcode; + char *message; +} ipq_errmap[] = { + { IPQ_ERR_NONE, "Unknown error" }, + { IPQ_ERR_IMPL, "Implementation error" }, + { IPQ_ERR_HANDLE, "Unable to create netlink handle" }, + { IPQ_ERR_SOCKET, "Unable to create netlink socket" }, + { IPQ_ERR_BIND, "Unable to bind netlink socket" }, + { IPQ_ERR_BUFFER, "Unable to allocate buffer" }, + { IPQ_ERR_RECV, "Failed to receive netlink message" }, + { IPQ_ERR_NLEOF, "Received EOF on netlink socket" }, + { IPQ_ERR_ADDRLEN, "Invalid peer address length" }, + { IPQ_ERR_STRUNC, "Sent message truncated" }, + { IPQ_ERR_RTRUNC, "Received message truncated" }, + { IPQ_ERR_NLRECV, "Received error from netlink" }, + { IPQ_ERR_SEND, "Failed to send netlink message" }, + { IPQ_ERR_SUPP, "Operation not supported" }, + { IPQ_ERR_RECVBUF, "Receive buffer size invalid" } +}; + +static int ipq_errno = IPQ_ERR_NONE; + +static ssize_t ipq_netlink_sendto(const struct ipq_handle *h, + const void *msg, size_t len); + +static ssize_t ipq_netlink_recvfrom(const struct ipq_handle *h, + unsigned char *buf, size_t len); + +static ssize_t ipq_netlink_sendmsg(const struct ipq_handle *h, + const struct msghdr *msg, + unsigned int flags); + +static char *ipq_strerror(int errcode); + +static ssize_t ipq_netlink_sendto(const struct ipq_handle *h, + const void *msg, size_t len) +{ + int status = sendto(h->fd, msg, len, 0, + (struct sockaddr *)&h->peer, sizeof(h->peer)); + if (status < 0) + ipq_errno = IPQ_ERR_SEND; + return status; +} + +static ssize_t ipq_netlink_sendmsg(const struct ipq_handle *h, + const struct msghdr *msg, + unsigned int flags) +{ + int status = sendmsg(h->fd, msg, flags); + if (status < 0) + ipq_errno = IPQ_ERR_SEND; + return status; +} + +static ssize_t ipq_netlink_recvfrom(const struct ipq_handle *h, + unsigned char *buf, size_t len) +{ + int addrlen, status; + struct nlmsghdr *nlh; + + if (len < sizeof(struct nlmsgerr)) { + ipq_errno = IPQ_ERR_RECVBUF; + return -1; + } + addrlen = sizeof(h->peer); + status = recvfrom(h->fd, buf, len, 0, + (struct sockaddr *)&h->peer, &addrlen); + if (status < 0) { + ipq_errno = IPQ_ERR_RECV; + return status; + } + if (addrlen != sizeof(h->peer)) { + ipq_errno = IPQ_ERR_RECV; + return -1; + } + if (status == 0) { + ipq_errno = IPQ_ERR_NLEOF; + return -1; + } + nlh = (struct nlmsghdr *)buf; + if (nlh->nlmsg_flags & MSG_TRUNC || nlh->nlmsg_len > status) { + ipq_errno = IPQ_ERR_RTRUNC; + return -1; + } + return status; +} + +static char *ipq_strerror(int errcode) +{ + if (errcode < 0 || errcode > IPQ_MAXERR) + errcode = IPQ_ERR_IMPL; + return ipq_errmap[errcode].message; +} + +/**************************************************************************** + * + * Public interface + * + ****************************************************************************/ + +/* + * Create and initialise an ipq handle. + * FIXME: implement flags. + */ +struct ipq_handle *ipq_create_handle(u_int32_t flags) +{ + int status; + struct ipq_handle *h; + + h = (struct ipq_handle *)malloc(sizeof(struct ipq_handle)); + if (h == NULL) { + ipq_errno = IPQ_ERR_HANDLE; + return NULL; + } + memset(h, 0, sizeof(struct ipq_handle)); + h->fd = socket(PF_NETLINK, SOCK_RAW, NETLINK_FIREWALL); + if (h->fd == -1) { + ipq_errno = IPQ_ERR_SOCKET; + close(h->fd); + free(h); + return NULL; + } + memset(&h->local, 0, sizeof(struct sockaddr_nl)); + h->local.nl_family = AF_NETLINK; + h->local.nl_pid = getpid(); + h->local.nl_groups = 0; + status = bind(h->fd, (struct sockaddr *)&h->local, sizeof(h->local)); + if (status == -1) { + ipq_errno = IPQ_ERR_BIND; + close(h->fd); + free(h); + return NULL; + } + memset(&h->peer, 0, sizeof(struct sockaddr_nl)); + h->peer.nl_family = AF_NETLINK; + h->peer.nl_pid = 0; + h->peer.nl_groups = 0; + return h; +} + +/* + * No error condition is checked here at this stage, but it may happen + * if/when reliable messaging is implemented. + */ +int ipq_destroy_handle(struct ipq_handle *h) +{ + if (h) { + close(h->fd); + free(h); + } + return 0; +} + +int ipq_set_mode(const struct ipq_handle *h, + u_int8_t mode, size_t range) +{ + struct { + struct nlmsghdr nlh; + ipq_peer_msg_t pm; + } req; + + memset(&req, 0, sizeof(req)); + req.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(req)); + req.nlh.nlmsg_flags = NLM_F_REQUEST; + req.nlh.nlmsg_type = IPQM_MODE; + req.nlh.nlmsg_pid = h->local.nl_pid; + req.pm.msg.mode.value = mode; + req.pm.msg.mode.range = range; + return ipq_netlink_sendto(h, (void *)&req, req.nlh.nlmsg_len); +} + +/* Note: timeout is not yet implemented */ +ssize_t ipq_read(const struct ipq_handle *h, + unsigned char *buf, size_t len, int timeout) +{ + return ipq_netlink_recvfrom(h, buf, len); +} + +int ipq_message_type(const unsigned char *buf) +{ + return ((struct nlmsghdr*)buf)->nlmsg_type; +} + +int ipq_get_msgerr(const unsigned char *buf) +{ + struct nlmsghdr *h = (struct nlmsghdr *)buf; + struct nlmsgerr *err = (struct nlmsgerr*)NLMSG_DATA(h); + return -err->error; +} + +ipq_packet_msg_t *ipq_get_packet(const unsigned char *buf) +{ + return NLMSG_DATA((struct nlmsghdr *)(buf)); +} + +int ipq_set_verdict(const struct ipq_handle *h, + unsigned long id, + unsigned int verdict, + size_t data_len, + unsigned char *buf) +{ + unsigned char nvecs; + size_t tlen; + struct nlmsghdr nlh; + ipq_peer_msg_t pm; + struct iovec iov[3]; + struct msghdr msg; + + memset(&nlh, 0, sizeof(nlh)); + nlh.nlmsg_flags = NLM_F_REQUEST; + nlh.nlmsg_type = IPQM_VERDICT; + nlh.nlmsg_pid = h->local.nl_pid; + memset(&pm, 0, sizeof(pm)); + pm.msg.verdict.value = verdict; + pm.msg.verdict.id = id; + pm.msg.verdict.data_len = data_len; + iov[0].iov_base = &nlh; + iov[0].iov_len = sizeof(nlh); + iov[1].iov_base = ± + iov[1].iov_len = sizeof(pm); + tlen = sizeof(nlh) + sizeof(pm); + nvecs = 2; + if (data_len && buf) { + iov[2].iov_base = buf; + iov[2].iov_len = data_len; + tlen += data_len; + nvecs++; + } + msg.msg_name = (void *)&h->peer; + msg.msg_namelen = sizeof(h->peer); + msg.msg_iov = iov; + msg.msg_iovlen = nvecs; + msg.msg_control = NULL; + msg.msg_controllen = 0; + msg.msg_flags = 0; + nlh.nlmsg_len = tlen; + return ipq_netlink_sendmsg(h, &msg, 0); +} + +/* Not implemented yet */ +int ipq_ctl(const struct ipq_handle *h, int request, ...) +{ + return 1; +} + +void ipq_perror(const char *s) +{ + if (s) + fputs(s, stderr); + else + fputs("ERROR", stderr); + if (ipq_errno) + fprintf(stderr, ": %s", ipq_strerror(ipq_errno)); + if (errno) + fprintf(stderr, ": %s", strerror(errno)); + fputc('\n', stderr); +} -- cgit v1.2.3