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CI: Call print_so_deps() on rpcapd in remote enabled build
[libpcap] / pcap-netfilter-linux.c
index 2eb0fc8c02aebd42a223f6f26367a2e1464c21f7..90296be71b781dc9a3be4dcf31b9876275a5a960 100644 (file)
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifdef HAVE_CONFIG_H
 #include <config.h>
-#endif
 
 #include "pcap-int.h"
 #include "diag-control.h"
 
-#ifdef NEED_STRERROR_H
-#include "strerror.h"
-#endif
-
 #include <errno.h>
 #include <stdlib.h>
 #include <unistd.h>
@@ -61,7 +55,7 @@
  *       It took me quite some time to debug ;/
  *
  *       Sending any data to nfnetlink socket requires CAP_NET_ADMIN privileges,
- *       and in nfqueue we need to send verdict reply after recving packet.
+ *       and in nfqueue we need to send verdict reply after receiving packet.
  *
  *       In tcpdump you can disable dropping privileges with -Z root
  */
@@ -92,7 +86,7 @@ netfilter_read_linux(pcap_t *handle, int max_packets, pcap_handler callback, u_c
        struct pcap_netfilter *handlep = handle->priv;
        register u_char *bp, *ep;
        int count = 0;
-       ssize_t len;
+       u_int cc;
 
        /*
         * Has "pcap_breakloop()" been called?
@@ -106,8 +100,8 @@ netfilter_read_linux(pcap_t *handle, int max_packets, pcap_handler callback, u_c
                handle->break_loop = 0;
                return PCAP_ERROR_BREAK;
        }
-       len = handle->cc;
-       if (len == 0) {
+       cc = handle->cc;
+       if (cc == 0) {
                /*
                 * The buffer is empty; refill it.
                 *
@@ -117,22 +111,31 @@ netfilter_read_linux(pcap_t *handle, int max_packets, pcap_handler callback, u_c
                 * to set handle->break_loop (we ignore it on other
                 * platforms as well).
                 */
+               ssize_t read_ret;
+
                do {
-                       len = recv(handle->fd, handle->buffer, handle->bufsize, 0);
+                       read_ret = recv(handle->fd, handle->buffer, handle->bufsize, 0);
                        if (handle->break_loop) {
                                handle->break_loop = 0;
                                return PCAP_ERROR_BREAK;
                        }
-                       if (errno == ENOBUFS)
+                       if (read_ret == -1 && errno == ENOBUFS)
                                handlep->packets_nobufs++;
-               } while ((len == -1) && (errno == EINTR || errno == ENOBUFS));
+               } while ((read_ret == -1) && (errno == EINTR || errno == ENOBUFS));
 
-               if (len < 0) {
-                       pcap_fmt_errmsg_for_errno(handle->errbuf,
+               if (read_ret < 0) {
+                       pcapint_fmt_errmsg_for_errno(handle->errbuf,
                            PCAP_ERRBUF_SIZE, errno, "Can't receive packet");
                        return PCAP_ERROR;
                }
 
+               /*
+                * At this point, read_ret is guaranteed to be
+                * >= 0 and < p->bufsize; p->bufsize is a u_int,
+                * so its value is guaranteed to fit in cc, which
+                * is also a u_int.
+                */
+               cc = (u_int)read_ret;
                bp = (unsigned char *)handle->buffer;
        } else
                bp = handle->bp;
@@ -143,7 +146,7 @@ netfilter_read_linux(pcap_t *handle, int max_packets, pcap_handler callback, u_c
         * This assumes that a single buffer of message will have
         * <= INT_MAX packets, so the message count doesn't overflow.
         */
-       ep = bp + len;
+       ep = bp + cc;
        while (bp < ep) {
                const struct nlmsghdr *nlh = (const struct nlmsghdr *) bp;
                uint32_t msg_len;
@@ -160,7 +163,7 @@ netfilter_read_linux(pcap_t *handle, int max_packets, pcap_handler callback, u_c
                 */
                if (handle->break_loop) {
                        handle->bp = bp;
-                       handle->cc = (int)(ep - bp);
+                       handle->cc = (u_int)(ep - bp);
                        if (count == 0) {
                                handle->break_loop = 0;
                                return PCAP_ERROR_BREAK;
@@ -186,8 +189,8 @@ netfilter_read_linux(pcap_t *handle, int max_packets, pcap_handler callback, u_c
                        break;
                }
 
-               if (nlh->nlmsg_len < sizeof(struct nlmsghdr) || (u_int)len < nlh->nlmsg_len) {
-                       snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Message truncated: (got: %zd) (nlmsg_len: %u)", len, nlh->nlmsg_len);
+               if (nlh->nlmsg_len < sizeof(struct nlmsghdr) || cc < nlh->nlmsg_len) {
+                       snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Message truncated: (got: %u) (nlmsg_len: %u)", cc, nlh->nlmsg_len);
                        return -1;
                }
 
@@ -259,7 +262,7 @@ netfilter_read_linux(pcap_t *handle, int max_packets, pcap_handler callback, u_c
 
                                gettimeofday(&pkth.ts, NULL);
                                if (handle->fcode.bf_insns == NULL ||
-                                               pcap_filter(handle->fcode.bf_insns, payload, pkth.len, pkth.caplen))
+                                               pcapint_filter(handle->fcode.bf_insns, payload, pkth.len, pkth.caplen))
                                {
                                        handlep->packets_read++;
                                        callback(user, &pkth, payload);
@@ -295,9 +298,7 @@ netfilter_read_linux(pcap_t *handle, int max_packets, pcap_handler callback, u_c
                bp += msg_len;
                if (count >= max_packets && !PACKET_COUNT_IS_UNLIMITED(max_packets)) {
                        handle->bp = bp;
-                       handle->cc = (int)(ep - bp);
-                       if (handle->cc < 0)
-                               handle->cc = 0;
+                       handle->cc = (u_int)(ep - bp);
                        return count;
                }
        }
@@ -595,17 +596,17 @@ netfilter_activate(pcap_t* handle)
        handle->offset = 0;
        handle->read_op = netfilter_read_linux;
        handle->inject_op = netfilter_inject_linux;
-       handle->setfilter_op = install_bpf_program; /* no kernel filtering */
+       handle->setfilter_op = pcapint_install_bpf_program; /* no kernel filtering */
        handle->setdirection_op = NULL;
        handle->set_datalink_op = netfilter_set_datalink;
-       handle->getnonblock_op = pcap_getnonblock_fd;
-       handle->setnonblock_op = pcap_setnonblock_fd;
+       handle->getnonblock_op = pcapint_getnonblock_fd;
+       handle->setnonblock_op = pcapint_setnonblock_fd;
        handle->stats_op = netfilter_stats_linux;
 
        /* Create netlink socket */
        handle->fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_NETFILTER);
        if (handle->fd < 0) {
-               pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
+               pcapint_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
                    errno, "Can't create raw socket");
                return PCAP_ERROR;
        }
@@ -613,32 +614,35 @@ netfilter_activate(pcap_t* handle)
        if (type == NFLOG) {
                handle->linktype = DLT_NFLOG;
                handle->dlt_list = (u_int *) malloc(sizeof(u_int) * 2);
-               if (handle->dlt_list != NULL) {
-                       handle->dlt_list[0] = DLT_NFLOG;
-                       handle->dlt_list[1] = DLT_IPV4;
-                       handle->dlt_count = 2;
+               if (handle->dlt_list == NULL) {
+                       pcapint_fmt_errmsg_for_errno(handle->errbuf,
+                           PCAP_ERRBUF_SIZE, errno,
+                           "Can't allocate DLT list");
+                       goto close_fail;
                }
-
+               handle->dlt_list[0] = DLT_NFLOG;
+               handle->dlt_list[1] = DLT_IPV4;
+               handle->dlt_count = 2;
        } else
                handle->linktype = DLT_IPV4;
 
        handle->buffer = malloc(handle->bufsize);
        if (!handle->buffer) {
-               pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
+               pcapint_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
                    errno, "Can't allocate dump buffer");
                goto close_fail;
        }
 
        if (type == NFLOG) {
                if (nflog_send_config_cmd(handle, 0, NFULNL_CFG_CMD_PF_UNBIND, AF_INET) < 0) {
-                       pcap_fmt_errmsg_for_errno(handle->errbuf,
+                       pcapint_fmt_errmsg_for_errno(handle->errbuf,
                            PCAP_ERRBUF_SIZE, errno,
                            "NFULNL_CFG_CMD_PF_UNBIND");
                        goto close_fail;
                }
 
                if (nflog_send_config_cmd(handle, 0, NFULNL_CFG_CMD_PF_BIND, AF_INET) < 0) {
-                       pcap_fmt_errmsg_for_errno(handle->errbuf,
+                       pcapint_fmt_errmsg_for_errno(handle->errbuf,
                            PCAP_ERRBUF_SIZE, errno, "NFULNL_CFG_CMD_PF_BIND");
                        goto close_fail;
                }
@@ -646,14 +650,14 @@ netfilter_activate(pcap_t* handle)
                /* Bind socket to the nflog groups */
                for (i = 0; i < group_count; i++) {
                        if (nflog_send_config_cmd(handle, groups[i], NFULNL_CFG_CMD_BIND, AF_UNSPEC) < 0) {
-                               pcap_fmt_errmsg_for_errno(handle->errbuf,
+                               pcapint_fmt_errmsg_for_errno(handle->errbuf,
                                    PCAP_ERRBUF_SIZE, errno,
                                    "Can't listen on group index");
                                goto close_fail;
                        }
 
                        if (nflog_send_config_mode(handle, groups[i], NFULNL_COPY_PACKET, handle->snapshot) < 0) {
-                               pcap_fmt_errmsg_for_errno(handle->errbuf,
+                               pcapint_fmt_errmsg_for_errno(handle->errbuf,
                                    PCAP_ERRBUF_SIZE, errno,
                                    "NFULNL_COPY_PACKET");
                                goto close_fail;
@@ -662,13 +666,13 @@ netfilter_activate(pcap_t* handle)
 
        } else {
                if (nfqueue_send_config_cmd(handle, 0, NFQNL_CFG_CMD_PF_UNBIND, AF_INET) < 0) {
-                       pcap_fmt_errmsg_for_errno(handle->errbuf,
+                       pcapint_fmt_errmsg_for_errno(handle->errbuf,
                            PCAP_ERRBUF_SIZE, errno, "NFQNL_CFG_CMD_PF_UNBIND");
                        goto close_fail;
                }
 
                if (nfqueue_send_config_cmd(handle, 0, NFQNL_CFG_CMD_PF_BIND, AF_INET) < 0) {
-                       pcap_fmt_errmsg_for_errno(handle->errbuf,
+                       pcapint_fmt_errmsg_for_errno(handle->errbuf,
                            PCAP_ERRBUF_SIZE, errno, "NFQNL_CFG_CMD_PF_BIND");
                        goto close_fail;
                }
@@ -676,14 +680,14 @@ netfilter_activate(pcap_t* handle)
                /* Bind socket to the nfqueue groups */
                for (i = 0; i < group_count; i++) {
                        if (nfqueue_send_config_cmd(handle, groups[i], NFQNL_CFG_CMD_BIND, AF_UNSPEC) < 0) {
-                               pcap_fmt_errmsg_for_errno(handle->errbuf,
+                               pcapint_fmt_errmsg_for_errno(handle->errbuf,
                                    PCAP_ERRBUF_SIZE, errno,
                                    "Can't listen on group index");
                                goto close_fail;
                        }
 
                        if (nfqueue_send_config_mode(handle, groups[i], NFQNL_COPY_PACKET, handle->snapshot) < 0) {
-                               pcap_fmt_errmsg_for_errno(handle->errbuf,
+                               pcapint_fmt_errmsg_for_errno(handle->errbuf,
                                    PCAP_ERRBUF_SIZE, errno,
                                    "NFQNL_COPY_PACKET");
                                goto close_fail;
@@ -695,7 +699,7 @@ netfilter_activate(pcap_t* handle)
                /*
                 * Monitor mode doesn't apply to netfilter devices.
                 */
-               pcap_cleanup_live_common(handle);
+               pcapint_cleanup_live_common(handle);
                return PCAP_ERROR_RFMON_NOTSUP;
        }
 
@@ -704,7 +708,7 @@ netfilter_activate(pcap_t* handle)
                 * Set the socket buffer size to the specified value.
                 */
                if (setsockopt(handle->fd, SOL_SOCKET, SO_RCVBUF, &handle->opt.buffer_size, sizeof(handle->opt.buffer_size)) == -1) {
-                       pcap_fmt_errmsg_for_errno(handle->errbuf,
+                       pcapint_fmt_errmsg_for_errno(handle->errbuf,
                            PCAP_ERRBUF_SIZE, errno, "SO_RCVBUF");
                        goto close_fail;
                }
@@ -714,7 +718,7 @@ netfilter_activate(pcap_t* handle)
        return 0;
 
 close_fail:
-       pcap_cleanup_live_common(handle);
+       pcapint_cleanup_live_common(handle);
        return PCAP_ERROR;
 }
 
@@ -725,9 +729,7 @@ netfilter_create(const char *device, char *ebuf, int *is_ours)
        pcap_t *p;
 
        /* Does this look like an netfilter device? */
-       cp = strrchr(device, '/');
-       if (cp == NULL)
-               cp = device;
+       cp = device;
 
        /* Does it begin with NFLOG_IFACE or NFQUEUE_IFACE? */
        if (strncmp(cp, NFLOG_IFACE, sizeof NFLOG_IFACE - 1) == 0)
@@ -771,7 +773,7 @@ netfilter_findalldevs(pcap_if_list_t *devlistp, char *err_str)
                /* if netlink is not supported this is not fatal */
                if (errno == EAFNOSUPPORT || errno == EPROTONOSUPPORT)
                        return 0;
-               pcap_fmt_errmsg_for_errno(err_str, PCAP_ERRBUF_SIZE,
+               pcapint_fmt_errmsg_for_errno(err_str, PCAP_ERRBUF_SIZE,
                    errno, "Can't open netlink socket");
                return -1;
        }
@@ -781,11 +783,11 @@ netfilter_findalldevs(pcap_if_list_t *devlistp, char *err_str)
         * The notion of "connected" vs. "disconnected" doesn't apply.
         * XXX - what about "up" and "running"?
         */
-       if (add_dev(devlistp, NFLOG_IFACE,
+       if (pcapint_add_dev(devlistp, NFLOG_IFACE,
            PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE,
            "Linux netfilter log (NFLOG) interface", err_str) == NULL)
                return -1;
-       if (add_dev(devlistp, NFQUEUE_IFACE,
+       if (pcapint_add_dev(devlistp, NFQUEUE_IFACE,
            PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE,
            "Linux netfilter queue (NFQUEUE) interface", err_str) == NULL)
                return -1;