1 /* $OpenBSD: syslogc.c,v 1.14 2008/09/10 22:17:33 sobrado Exp $ */ 2 3 /* 4 * Copyright (c) 2004 Damien Miller 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 #include <sys/types.h> 20 #include <sys/socket.h> 21 #include <sys/un.h> 22 23 #include <err.h> 24 #include <stdio.h> 25 #include <stdlib.h> 26 #include <string.h> 27 #include <unistd.h> 28 29 #define DEFAULT_CTLSOCK "/var/run/syslogd.sock" 30 31 #define MAX_MEMBUF_NAME 64 /* Max length of membuf log name */ 32 33 /* 34 * Client protocol NB. all numeric fields in network byte order 35 */ 36 #define CTL_VERSION 1 37 38 /* Request */ 39 struct ctl_cmd { 40 u_int32_t version; 41 #define CMD_READ 1 /* Read out log */ 42 #define CMD_READ_CLEAR 2 /* Read and clear log */ 43 #define CMD_CLEAR 3 /* Clear log */ 44 #define CMD_LIST 4 /* List available logs */ 45 #define CMD_FLAGS 5 /* Query flags only */ 46 #define CMD_READ_CONT 6 /* Read out log continuously */ 47 u_int32_t cmd; 48 char logname[MAX_MEMBUF_NAME]; 49 }; 50 51 /* Reply */ 52 struct ctl_reply_hdr { 53 u_int32_t version; 54 #define CTL_HDR_FLAG_OVERFLOW 0x01 55 u_int32_t flags; 56 /* Reply text follows, up to MAX_MEMBUF long */ 57 }; 58 59 static void 60 usage(void) 61 { 62 extern char *__progname; 63 64 fprintf(stderr, "usage: %s [-Ccfo] [-s reporting_socket] logname\n" 65 " %s -q\n", __progname, __progname); 66 exit(1); 67 } 68 69 int 70 main(int argc, char **argv) 71 { 72 const char *ctlsock_path; 73 char buf[8192]; 74 struct sockaddr_un ctl; 75 int ctlsock, ch, oflag, rval; 76 FILE *ctlf; 77 extern char *optarg; 78 extern int optind; 79 struct ctl_cmd cc; 80 struct ctl_reply_hdr rr; 81 82 memset(&cc, '\0', sizeof(cc)); 83 84 ctlsock_path = DEFAULT_CTLSOCK; 85 rval = oflag = 0; 86 while ((ch = getopt(argc, argv, "Ccfhoqs:")) != -1) { 87 switch (ch) { 88 case 'C': 89 cc.cmd = CMD_CLEAR; 90 break; 91 case 'c': 92 cc.cmd = CMD_READ_CLEAR; 93 break; 94 case 'h': 95 usage(); 96 break; 97 case 'f': 98 cc.cmd = CMD_READ_CONT; 99 break; 100 case 'o': 101 cc.cmd = CMD_FLAGS; 102 oflag = 1; 103 break; 104 case 'q': 105 cc.cmd = CMD_LIST; 106 break; 107 case 's': 108 ctlsock_path = optarg; 109 break; 110 default: 111 usage(); 112 break; 113 } 114 } 115 116 if (cc.cmd == 0) 117 cc.cmd = CMD_READ; 118 119 if ((cc.cmd != CMD_LIST && optind != argc - 1) || 120 (cc.cmd == CMD_LIST && optind != argc)) 121 usage(); 122 123 if (cc.cmd != CMD_LIST) { 124 if (strlcpy(cc.logname, argv[optind], sizeof(cc.logname)) >= 125 sizeof(cc.logname)) 126 errx(1, "Specified log name is too long"); 127 } 128 129 memset(&ctl, '\0', sizeof(ctl)); 130 strlcpy(ctl.sun_path, ctlsock_path, sizeof(ctl.sun_path)); 131 ctl.sun_family = AF_UNIX; 132 133 if ((ctlsock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1) 134 err(1, "socket"); 135 if (connect(ctlsock, (struct sockaddr *)&ctl, sizeof(ctl)) == -1) 136 err(1, "connect: %s", ctl.sun_path); 137 if ((ctlf = fdopen(ctlsock, "r+")) == NULL) 138 err(1, "fdopen"); 139 140 cc.version = htonl(CTL_VERSION); 141 cc.cmd = htonl(cc.cmd); 142 /* Send command */ 143 if (fwrite(&cc, sizeof(cc), 1, ctlf) != 1) 144 err(1, "fwrite"); 145 146 fflush(ctlf); 147 setlinebuf(ctlf); 148 149 /* Fetch header */ 150 if (fread(&rr, sizeof(rr), 1, ctlf) != 1) 151 err(1, "fread header"); 152 153 if (ntohl(rr.version) != CTL_VERSION) 154 errx(1, "unsupported syslogd version"); 155 156 /* Write out reply */ 157 while ((fgets(buf, sizeof(buf), ctlf)) != NULL) { 158 if (!strcmp(buf, "<ENOBUFS>\n")) 159 fprintf(stderr, "syslogc [%s]: Lines were dropped!\n", 160 cc.logname); 161 else 162 fputs(buf, stdout); 163 } 164 165 if (oflag && (ntohl(rr.flags) & CTL_HDR_FLAG_OVERFLOW)) { 166 printf("%s has overflowed\n", cc.logname); 167 rval = 1; 168 } 169 170 fclose(ctlf); 171 close(ctlsock); 172 173 exit(rval); 174 } 175