Replace some command name 'Tcpdump' with 'tcpdump'

[tcpdump] / tcpdump.c

diff --git a/tcpdump.c b/tcpdump.c
index 219ac2a2bde47e72dc60de99dbfb6030f874d9d1..7159d1c76fd8677ea395f6e4321c58768f27721e 100644 (file)
--- a/tcpdump.c
+++ b/tcpdump.c
@@ -563,8 +563,21 @@ show_remote_devices_and_exit(void)
        int i;
 
        if (pcap_findalldevs_ex(remote_interfaces_source, NULL, &devlist,
-           ebuf) < 0)
+           ebuf) < 0) {
+               if (strcmp(ebuf, "not supported") == 0) {
+                       /*
+                        * macOS 14's pcap_findalldevs_ex(), which is a
+                        * stub that always returns -1 with an error
+                        * message of "not supported".
+                        *
+                        * In this case, as we passed it an rpcap://
+                        * URL, treat that as meaning "remote capture
+                        * not supported".
+                        */
+                       error("Remote capture not supported");
+               }
                error("%s", ebuf);
+       }
        for (i = 0, dev = devlist; dev != NULL; i++, dev = dev->next) {
                printf("%d.%s", i+1, dev->name);
                if (dev->description != NULL)
@@ -796,7 +809,7 @@ droproot(const char *username, const char *chroot_dir)
        } else
                error("Couldn't find user '%.32s'", username);
 #ifdef HAVE_LIBCAP_NG
-       /* We don't need CAP_SETUID, CAP_SETGID and CAP_SYS_CHROOT any more. */
+       /* We don't need CAP_SETUID, CAP_SETGID and CAP_SYS_CHROOT anymore. */
 DIAG_OFF_ASSIGN_ENUM
        capng_updatev(
                CAPNG_DROP,
@@ -968,7 +981,7 @@ tstamp_precision_to_string(int precision)
  * along the lines of ioctl(), the fact that ioctl() operations are
  * largely specific to particular character devices but fcntl() operations
  * are either generic to all descriptors or generic to all descriptors for
- * regular files nonwithstanding.
+ * regular files notwithstanding.
  *
  * The Capsicum people decided that fine-grained control of descriptor
  * operations was required, so that you need to grant permission for
@@ -984,7 +997,7 @@ tstamp_precision_to_string(int precision)
  * that requires that it be able to do an F_GETFL fcntl() to read
  * the O_ flags.
  *
- * Tcpdump uses ftell() to determine how much data has been written
+ * tcpdump uses ftell() to determine how much data has been written
  * to a file in order to, when used with -C, determine when it's time
  * to rotate capture files.  ftell() therefore needs to do an lseek()
  * to find out the file offset and must, thanks to the aforementioned
@@ -1269,6 +1282,18 @@ open_interface(const char *device, netdissect_options *ndo, char *ebuf)
                    pflag ? 0 : PCAP_OPENFLAG_PROMISCUOUS, timeout, NULL,
                    ebuf);
                if (pc == NULL) {
+                       /*
+                        * macOS 14's pcap_pcap_open(), which is a
+                        * stub that always returns NULL with an error
+                        * message of "not supported".
+                        *
+                        * In this case, as we passed it an rpcap://
+                        * URL, treat that as meaning "remote capture
+                        * not supported".
+                        */
+                       if (strcmp(ebuf, "not supported") == 0)
+                               error("Remote capture not supported");
+
                        /*
                         * If this failed with "No such device" or "The system
                         * cannot find the device specified", that means
@@ -1438,7 +1463,7 @@ open_interface(const char *device, netdissect_options *ndo, char *ebuf)
                if (status != 0)
                        error("%s: pcap_setdirection() failed: %s",
                              device,  pcap_geterr(pc));
-               }
+       }
 #endif /* HAVE_PCAP_SETDIRECTION */
 #else /* HAVE_PCAP_CREATE */
        *ebuf = '\0';
@@ -1550,6 +1575,13 @@ main(int argc, char **argv)
        if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
                error("%s", ebuf);
 
+       /*
+        * An explicit tzset() call is usually not needed as it happens
+        * implicitly the first time we call localtime() or mktime(),
+        * but in some cases (sandboxing, chroot) this may be too late.
+        */
+       tzset();
+
        while (
            (op = getopt_long(argc, argv, SHORTOPTS, longopts, NULL)) != -1)
                switch (op) {
@@ -1776,7 +1808,7 @@ main(int argc, char **argv)
                                if (nd_load_smi_module(optarg, ebuf, sizeof(ebuf)) == -1)
                                        error("%s", ebuf);
                        } else {
-                               (void)fprintf(stderr, "%s: ignoring option `-m %s' ",
+                               (void)fprintf(stderr, "%s: ignoring option '-m %s' ",
                                              program_name, optarg);
                                (void)fprintf(stderr, "(no libsmi support)\n");
                        }
@@ -1820,7 +1852,7 @@ main(int argc, char **argv)
                        else if (ascii_strcasecmp(optarg, "inout") == 0)
                                Qflag = PCAP_D_INOUT;
                        else
-                               error("unknown capture direction `%s'", optarg);
+                               error("unknown capture direction '%s'", optarg);
                        break;
 #endif /* HAVE_PCAP_SETDIRECTION */
 
@@ -1888,7 +1920,7 @@ main(int argc, char **argv)
                        else if (ascii_strcasecmp(optarg, "quic") == 0)
                                ndo->ndo_packettype = PT_QUIC;
                        else
-                               error("unknown packet type `%s'", optarg);
+                               error("unknown packet type '%s'", optarg);
                        break;
 
                case 'u':
@@ -2078,6 +2110,8 @@ main(int argc, char **argv)
                /* Run with '-Z root' to restore old behaviour */
                if (!username)
                        username = WITH_USER;
+               else if (strcmp(username, "root") == 0)
+                       username = NULL;
        }
 #endif
 
@@ -2292,8 +2326,11 @@ main(int argc, char **argv)
                         * on; this may be a non-Linux "any" device
                         * that doesn't support DLT_LINUX_SLL2.
                         */
-                       if (strcmp(device, "any") == 0)
+                       if (strcmp(device, "any") == 0) {
+DIAG_OFF_WARN_UNUSED_RESULT
                                (void) pcap_set_datalink(pd, DLT_LINUX_SLL2);
+DIAG_ON_WARN_UNUSED_RESULT
+                       }
                }
 #endif
                i = pcap_snapshot(pd);
@@ -2360,7 +2397,7 @@ main(int argc, char **argv)
         * devices, and can't just give users that permission,
         * you'd make tcpdump set-UID or set-GID).
         *
-        * Tcpdump doesn't necessarily write only to one savefile;
+        * tcpdump doesn't necessarily write only to one savefile;
         * the general only way to allow a -Z instance to write to
         * savefiles as the user under whose UID it's run, rather
         * than as the user specified with -Z, would thus be to switch