Add config file support for logsrvd

MANIFEST

@@ -50,6 +50,7 @@ doc/visudo.mdoc.in
 examples/Makefile.in
 examples/pam.conf
 examples/sudo.conf
+examples/sudo_logsrvd.conf
 examples/sudoers
 examples/syslog.conf
 include/Makefile.in
@@ -236,6 +237,7 @@ logsrvd/log_server.proto
 logsrvd/iolog_writer.c
 logsrvd/logsrvd.c
 logsrvd/logsrvd.h
+logsrvd/logsrvd_conf.c
 logsrvd/protobuf-c/protobuf-c.c
 logsrvd/protobuf-c/protobuf-c.h
 logsrvd/sendlog.c

examples/sudo_logsrvd.conf

@@ -0,0 +1,49 @@
+#
+# sudo logsrv configuration
+#
+
+# The top-level directory to use when constructing the path name for the
+# I/O log directory.  The session sequence number, if any, is stored here.
+iolog_dir = /var/log/sudo-io
+
+# The path name, relative to iolog_dir, in which to store I/O logs.
+# Note that iolog_file may contain directory components.
+iolog_file = %{seq}
+
+# If set, I/O log data is flushed to disk after each write instead of
+# buffering it.  This makes it possible to view the logs in real-time
+# as the program is executing but may significantly reduce the effectiveness
+# of I/O log compression.
+iolog_flush = true
+
+# If set, I/O logs will be compressed using zlib.  Enabling compression can
+# make it harder to view the logs in real-time as the program is executing.
+iolog_compress = false
+
+# The group name to look up when setting the group-ID on new I/O log files
+# and directories.  If iolog_group is not set, the primary group-ID of the
+# user specified by iolog_user is used.  If neither iolog_group nor iolog_user
+# are set, I/O log files and directories are created with group-ID 0.
+#iolog_group = wheel
+
+# The user name to look up when setting the user and group-IDs on new I/O
+# log files and directories.  If iolog_group is set, it will be used instead
+# of the user's primary group-ID.  By default, I/O log files and directories
+# are created with user and group-ID 0.
+#iolog_user = root
+
+# The file mode to use when creating I/O log files.  Mode bits for read and
+# write permissions for owner, group or other are honored, everything else
+# is ignored.  The file permissions will always include the owner read and
+# write bits, even if they are not present in the specified mode.  When
+# creating I/O log directories, search (execute) bits are added to match
+# the read and write bits specified by iolog_mode.
+iolog_mode = 0600
+
+# The maximum sequence number that will be substituted for the %{seq}
+# escape in the I/O log file (see the iolog_dir description below for
+# more information).  While the value substituted for %{seq} is in
+# base 36, maxseq itself should be expressed in decimal.  Values larger
+# than 2176782336 (which corresponds to the base 36 sequence number
+# ZZZZZZ) will be silently truncated to 2176782336.
+maxseq = 2176782336

logsrvd/Makefile.in

@@ -108,8 +108,8 @@ SHELL = @SHELL@
 
 PROGS = logsrvd sendlog
 
-LOGSRVD_OBJS = iolog_util.o iolog_writer.o logsrvd.o log_server.pb-c.o \
+LOGSRVD_OBJS = iolog_util.o iolog_writer.o logsrvd.o logsrvd_conf.o \
-	       protobuf-c.o
+	       log_server.pb-c.o protobuf-c.o
 
 SENDLOG_OBJS = sendlog.o iolog_util.o log_server.pb-c.o protobuf-c.o
 
@@ -272,6 +272,24 @@ logsrvd.i: $(srcdir)/logsrvd.c $(devdir)/log_server.pb-c.h \
 	$(CC) -E -o $@ $(CPPFLAGS) $<
 logsrvd.plog: logsrvd.i
 	rm -f $@; pvs-studio --cfg $(PVS_CFG) --sourcetree-root $(top_srcdir) --skip-cl-exe yes --source-file $(srcdir)/logsrvd.c --i-file $< --output-file $@
+logsrvd_conf.o: $(srcdir)/logsrvd_conf.c $(devdir)/log_server.pb-c.h \
+                $(incdir)/compat/stdbool.h $(incdir)/sudo_compat.h \
+                $(incdir)/sudo_debug.h $(incdir)/sudo_fatal.h \
+                $(incdir)/sudo_gettext.h $(incdir)/sudo_queue.h \
+                $(incdir)/sudo_util.h $(srcdir)/logsrvd.h \
+                $(srcdir)/protobuf-c/protobuf-c.h $(sudoers_srcdir)/iolog.h \
+                $(top_builddir)/config.h $(top_builddir)/pathnames.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $(ASAN_CFLAGS) $(PIE_CFLAGS) $(SSP_CFLAGS) $(srcdir)/logsrvd_conf.c
+logsrvd_conf.i: $(srcdir)/logsrvd_conf.c $(devdir)/log_server.pb-c.h \
+                $(incdir)/compat/stdbool.h $(incdir)/sudo_compat.h \
+                $(incdir)/sudo_debug.h $(incdir)/sudo_fatal.h \
+                $(incdir)/sudo_gettext.h $(incdir)/sudo_queue.h \
+                $(incdir)/sudo_util.h $(srcdir)/logsrvd.h \
+                $(srcdir)/protobuf-c/protobuf-c.h $(sudoers_srcdir)/iolog.h \
+                $(top_builddir)/config.h $(top_builddir)/pathnames.h
+	$(CC) -E -o $@ $(CPPFLAGS) $<
+logsrvd_conf.plog: logsrvd_conf.i
+	rm -f $@; pvs-studio --cfg $(PVS_CFG) --sourcetree-root $(top_srcdir) --skip-cl-exe yes --source-file $(srcdir)/logsrvd_conf.c --i-file $< --output-file $@
 protobuf-c.o: $(srcdir)/protobuf-c/protobuf-c.c 
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $(ASAN_CFLAGS) $(PIE_CFLAGS) $(SSP_CFLAGS) $(srcdir)/protobuf-c/protobuf-c.c
 protobuf-c.i: $(srcdir)/protobuf-c/protobuf-c.c 

logsrvd/iolog_writer.c

@@ -231,7 +231,8 @@ iolog_details_fill(struct iolog_details *details, ExecMessage *msg)
 
 /*
  * Create I/O log path
- * Set iolog_dir and iolog_dir_fd in the closure
+ * Sets iolog_dir and iolog_dir_fd in the closure
+ * XXX - use iolog_dir and iolog_file code from sudoers/iolog.c
  */
 static bool
 create_iolog_dir(struct iolog_details *details, struct connection_closure *closure)

logsrvd/logsrvd.c

@@ -53,16 +53,23 @@
 #include "pathnames.h"
 #include "logsrvd.h"
 
+/*
+ * Sudo I/O audit server.
+ */
+
 TAILQ_HEAD(connection_list, connection_closure);
 static struct connection_list connections = TAILQ_HEAD_INITIALIZER(connections);
 static const char server_id[] = "Sudo Audit Server 0.1";
+static const char *conf_file = _PATH_SUDO_LOGSRVD_CONF;
 static double random_drop;
 
-/*
+union sockaddr_union {
- * Proof of concept audit server.
+    struct sockaddr sa;
- * Currently only handle a single connection at a time.
+    struct sockaddr_in sin;
- * TODO: use atomic I/O when we know the packed buffer size.
+#ifdef HAVE_STRUCT_IN6_ADDR
- */
+    struct sockaddr_in6 sin6;
+#endif
+};
 
 /*
  * Free a struct connection_closure container and its contents.
@@ -648,8 +655,8 @@ signal_cb(int signo, int what, void *v)
 
     switch (signo) {
 	case SIGHUP:
-	    /* TODO: reload config */
 	    sudo_debug_printf(SUDO_DEBUG_INFO, "received SIGHUP");
+	    logsrvd_conf_read(conf_file);
 	    break;
 	case SIGINT:
 	case SIGTERM:
@@ -903,7 +910,8 @@ daemonize(void)
 static void
 usage(void)
 {
-    fprintf(stderr, "usage: %s [-n] [-R percentage]\n", getprogname());
+    fprintf(stderr, "usage: %s [-n] [-f conf_file] [-R percentage]\n",
+	getprogname());
     exit(1);
 }
 
@@ -934,12 +942,16 @@ main(int argc, char *argv[])
 	sudo_fatalx("Protobuf-C version 1.3 or higher required");
 
     /* XXX - getopt_long option handling */
-    while ((ch = getopt(argc, argv, "nR:")) != -1) {
+    while ((ch = getopt(argc, argv, "f:nR:")) != -1) {
 	switch (ch) {
+	case 'f':
+	    conf_file = optarg;
+	    break;
 	case 'n':
 	    nofork = true;
 	    break;
 	case 'R':
+	    /* random connection drop probability as a percentage (debug) */
             errno = 0;
 	    random_drop = strtod(optarg, &ep);
             if (*ep != '\0' || errno != 0)
@@ -953,6 +965,9 @@ main(int argc, char *argv[])
     argc -= optind;
     argv += optind;
 
+    /* Read sudo_logsrvd.conf */
+    logsrvd_conf_read(conf_file);
+
     signal(SIGPIPE, SIG_IGN);
     if (!nofork)
 	daemonize();

logsrvd/logsrvd.h

@@ -72,14 +72,6 @@ enum connection_status {
     ERROR
 };
 
-union sockaddr_union {
-    struct sockaddr sa;
-    struct sockaddr_in sin;
-#ifdef HAVE_STRUCT_IN6_ADDR
-    struct sockaddr_in6 sin6;
-#endif
-};
-
 struct connection_buffer {
     uint8_t *data;		/* pre-allocated data buffer */
     unsigned int size;		/* currently always UINT16_MAX + 2 */
@@ -114,3 +106,14 @@ int store_iobuf(int iofd, IoBuffer *msg, struct connection_closure *closure);
 int store_suspend(CommandSuspend *msg, struct connection_closure *closure);
 int store_winsize(ChangeWindowSize *msg, struct connection_closure *closure);
 void iolog_close(struct connection_closure *closure);
+
+/* logsrvd_conf.c */
+bool logsrvd_conf_iolog_compress(void);
+bool logsrvd_conf_iolog_flush(void);
+const char *logsrvd_conf_iolog_dir(void);
+const char *logsrvd_conf_iolog_file(void);
+const char *logsrvd_conf_iolog_group(void);
+const char *logsrvd_conf_iolog_user(void);
+mode_t logsrvd_conf_iolog_mode(void);
+unsigned int logsrvd_conf_maxseq(void);
+void logsrvd_conf_read(const char *path);

logsrvd/logsrvd_conf.c

@@ -0,0 +1,235 @@
+/*
+ * Copyright (c) 2019 Todd C. Miller <Todd.Miller@courtesan.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "config.h"
+
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <errno.h>
+#include <ctype.h>
+#include <fcntl.h>
+#include <limits.h>
+#ifdef HAVE_STDBOOL_H
+# include <stdbool.h>
+#else
+# include "compat/stdbool.h"
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "log_server.pb-c.h"
+#include "sudo_gettext.h"	/* must be included before sudo_compat.h */
+#include "sudo_compat.h"
+#include "sudo_debug.h"
+#include "sudo_util.h"
+#include "sudo_fatal.h"
+#include "pathnames.h"
+#include "logsrvd.h"
+#include "iolog.h"
+
+enum config_type {
+    CONF_BOOL,
+    CONF_INT,
+    CONF_UINT,
+    CONF_MODE,
+    CONF_STR
+};
+
+union config_value {
+    char *strval;
+    int intval;
+    unsigned int uintval;
+    mode_t modeval;
+    bool boolval;
+};
+
+struct logsrvd_config_table {
+    char *conf_str;
+    enum config_type conf_type;
+    union config_value conf_val;
+};
+
+/* Indexes into conf_table */
+#define LOGSRVD_CONF_IOLOG_DIR		0
+#define LOGSRVD_CONF_IOLOG_FILE		1
+#define LOGSRVD_CONF_IOLOG_FLUSH	2
+#define LOGSRVD_CONF_IOLOG_COMPRESS	3
+#define LOGSRVD_CONF_IOLOG_USER		4
+#define LOGSRVD_CONF_IOLOG_GROUP	5
+#define LOGSRVD_CONF_IOLOG_MODE		6
+#define LOGSRVD_CONF_MAXSEQ		7
+
+/* XXX - use callbacks into iolog.c instead */
+static struct logsrvd_config_table conf_table[] = {
+    { "iolog_dir", CONF_STR, { .strval = _PATH_SUDO_IO_LOGDIR } },
+    { "iolog_file", CONF_STR, { .strval = "%{seq}" } },
+    { "iolog_flush", CONF_BOOL, { .boolval = true } },
+    { "iolog_compress", CONF_BOOL, { .boolval = false } },
+    { "iolog_user", CONF_STR, { .strval = NULL } },
+    { "iolog_group", CONF_STR, { .strval = NULL } },
+    { "iolog_mode", CONF_MODE, { .intval = S_IRUSR|S_IWUSR } },
+    { "maxseq", CONF_UINT, { .intval = SESSID_MAX } },
+    { NULL }
+};
+
+static bool
+parse_value(struct logsrvd_config_table *ct, const char *val)
+{
+    int ival;
+    unsigned int uval;
+    mode_t mode;
+    const char *errstr;
+    debug_decl(parse_value, SUDO_DEBUG_UTIL)
+
+    switch (ct->conf_type) {
+    case CONF_BOOL:
+	ival = sudo_strtobool(val);
+	if (ival == -1)
+	    debug_return_bool(false);
+	ct->conf_val.boolval = ival;
+	break;
+    case CONF_INT:
+	ival = sudo_strtonum(val, INT_MIN, INT_MAX, &errstr);
+	if (errstr != NULL)
+	    debug_return_bool(false);
+	ct->conf_val.intval = ival;
+	break;
+    case CONF_UINT:
+	uval = sudo_strtonum(val, 0, UINT_MAX, &errstr);
+	if (errstr != NULL)
+	    debug_return_bool(false);
+	ct->conf_val.uintval = uval;
+	break;
+    case CONF_MODE:
+	mode = sudo_strtomode(val, &errstr);
+	if (errstr != NULL)
+	    debug_return_bool(false);
+	ct->conf_val.modeval = mode;
+	break;
+    case CONF_STR:
+	ct->conf_val.strval = strdup(val);
+	if (ct->conf_val.strval == NULL)
+	    debug_return_bool(false);
+	break;
+    default:
+	debug_return_bool(false);
+    }
+
+    debug_return_bool(true);
+}
+
+void
+logsrvd_conf_read(const char *path)
+{
+    unsigned int lineno = 0;
+    size_t linesize = 0;
+    char *line = NULL;
+    FILE *fp;
+    debug_decl(read_config, SUDO_DEBUG_UTIL)
+
+    if ((fp = fopen(path, "r")) == NULL) {
+	if (errno != ENOENT)
+	    sudo_warn("%s", path);
+	debug_return;
+    }
+
+    while (sudo_parseln(&line, &linesize, &lineno, fp, 0) != -1) {
+	struct logsrvd_config_table *ct;
+	char *ep, *val;
+
+	// XXX - warn about bogus lines
+	if ((ep = strchr(line, '=')) == NULL)
+	    continue;
+	val = ep + 1;
+	while (isspace((unsigned char)*val))
+	    val++;
+	while (ep > line && isspace((unsigned char)ep[-1]))
+	    ep--;
+	*ep = '\0';
+	for (ct = conf_table; ct->conf_str != NULL; ct++) {
+	    if (strcmp(line, ct->conf_str) == 0) {
+		if (!parse_value(ct, val))
+		    sudo_warnx("invalid value for %s: %s", ct->conf_str, val);
+		break;
+	    }
+	}
+    }
+
+#if 0
+    /*
+     * TODO: iolog_dir, iolog_file, iolog_flush, iolog_compress
+     */
+    iolog_set_user(conf_table[LOGSRVD_CONF_IOLOG_USER].conf_val.strval);
+    iolog_set_group(conf_table[LOGSRVD_CONF_IOLOG_GROUP].conf_val.strval);
+    iolog_set_mode(conf_table[LOGSRVD_CONF_IOLOG_MODE].conf_val.modeval);
+    /* XXX - expects a string */
+    iolog_set_max_sessid(conf_table[LOGSRVD_CONF_MAXSEQ].conf_val.uintval);
+#endif
+
+    debug_return;
+}
+
+/* XXX - use callbacks instead */
+const char *
+logsrvd_conf_iolog_dir(void)
+{
+    return conf_table[LOGSRVD_CONF_IOLOG_DIR].conf_val.strval;
+}
+
+const char *
+logsrvd_conf_iolog_file(void)
+{
+    return conf_table[LOGSRVD_CONF_IOLOG_FILE].conf_val.strval;
+}
+
+const char *
+logsrvd_conf_iolog_user(void)
+{
+    return conf_table[LOGSRVD_CONF_IOLOG_USER].conf_val.strval;
+}
+
+const char *
+logsrvd_conf_iolog_group(void)
+{
+    return conf_table[LOGSRVD_CONF_IOLOG_GROUP].conf_val.strval;
+}
+
+bool
+logsrvd_conf_iolog_flush(void)
+{
+    return conf_table[LOGSRVD_CONF_IOLOG_FLUSH].conf_val.boolval;
+}
+
+bool
+logsrvd_conf_iolog_compress(void)
+{
+    return conf_table[LOGSRVD_CONF_IOLOG_COMPRESS].conf_val.boolval;
+}
+
+mode_t
+logsrvd_conf_iolog_mode(void)
+{
+    return conf_table[LOGSRVD_CONF_IOLOG_MODE].conf_val.modeval;
+}
+
+unsigned int
+logsrvd_conf_maxseq(void)
+{
+    return conf_table[LOGSRVD_CONF_MAXSEQ].conf_val.uintval;
+}

pathnames.h.in

@@ -78,6 +78,13 @@
 # define _PATH_CVTSUDOERS_CONF		"/etc/cvtsudoers.conf"
 #endif /* _PATH_CVTSUDOERS_CONF */
 
+/*
+ * NOTE: _PATH_SUDO_LOGSRVD_CONF is usually overridden by the Makefile.
+ */
+#ifndef _PATH_SUDO_LOGSRVD_CONF
+# define _PATH_SUDO_LOGSRVD_CONF	"/etc/sudo_logsrvd.conf"
+#endif /* _PATH_SUDO_LOGSRVD_CONF */
+
 /*
  * The following paths are controlled via the configure script.
  */