X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=procps%2Fsysctl.c;h=6d77185caec8ef5b2c6887b2a1df85f749acab13;hb=22c75924daa41b7ea097796afd4baafa2fc99d05;hp=a1294801798eb6f3aebc2d42dea78bab5e3b6cf9;hpb=5a28a25b9dd81e0975532458723c4244ff532e58;p=oweals%2Fbusybox.git

diff --git a/procps/sysctl.c b/procps/sysctl.c
index a12948017..6d77185ca 100644
--- a/procps/sysctl.c
+++ b/procps/sysctl.c
@@ -4,317 +4,344 @@
  *
  * Copyright 1999 George Staikos
  *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  *
  * Changelog:
- *	v1.01:
- *		- added -p <preload> to preload values from a file
- *	v1.01.1
- *		- busybox applet aware by <solar@gentoo.org>
- *
+ * v1.01   - added -p <preload> to preload values from a file
+ * v1.01.1 - busybox applet aware by <solar@gentoo.org>
  */
+//config:config BB_SYSCTL
+//config:	bool "sysctl (7.4 kb)"
+//config:	default y
+//config:	help
+//config:	Configure kernel parameters at runtime.
+
+//applet:IF_BB_SYSCTL(APPLET_NOEXEC(sysctl, sysctl, BB_DIR_SBIN, BB_SUID_DROP, sysctl))
+
+//kbuild:lib-$(CONFIG_BB_SYSCTL) += sysctl.o
+
+//usage:#define sysctl_trivial_usage
+//usage:       "-p [-enq] [FILE...] / [-enqaw] [KEY[=VALUE]]..."
+//usage:#define sysctl_full_usage "\n\n"
+//usage:       "Show/set kernel parameters\n"
+//usage:     "\n	-p	Set values from FILEs (default /etc/sysctl.conf)"
+//usage:     "\n	-e	Don't warn about unknown keys"
+//usage:     "\n	-n	Don't show key names"
+//usage:     "\n	-q      Quiet"
+//usage:     "\n	-a	Show all values"
+/* Same as -a, no need to show it */
+/* //usage:     "\n	-A	Show all values in table form" */
+//usage:     "\n	-w	Set values"
+//usage:
+//usage:#define sysctl_example_usage
+//usage:       "sysctl [-n] [-e] variable...\n"
+//usage:       "sysctl [-n] [-e] [-q] -w variable=value...\n"
+//usage:       "sysctl [-n] [-e] -a\n"
+//usage:       "sysctl [-n] [-e] [-q] -p file	(default /etc/sysctl.conf)\n"
+//usage:       "sysctl [-n] [-e] -A\n"
 
 #include "libbb.h"
 
-/*
- *    Function Prototypes
- */
-static int sysctl_read_setting(const char *setting, int output);
-static int sysctl_write_setting(const char *setting, int output);
-static int sysctl_preload_file(const char *filename, int output);
-static int sysctl_display_all(const char *path, int output, int show_table);
-
-/*
- *    Globals...
- */
-static const char ETC_SYSCTL_CONF[] ALIGN1 = "/etc/sysctl.conf";
-static const char PROC_SYS[] ALIGN1 = "/proc/sys/";
-enum { strlen_PROC_SYS = sizeof(PROC_SYS) - 1 };
-
-/* error messages */
-static const char ERR_UNKNOWN_PARAMETER[] ALIGN1 =
-	"error: unknown parameter '%s'";
-static const char ERR_MALFORMED_SETTING[] ALIGN1 =
-	"error: malformed setting '%s'";
-static const char ERR_NO_EQUALS[] ALIGN1 =
-	"error: '%s' must be of the form name=value";
-static const char ERR_INVALID_KEY[] ALIGN1 =
-	"error: '%s' is an unknown key";
-static const char ERR_UNKNOWN_WRITING[] ALIGN1 =
-	"error setting key '%s'";
-static const char ERR_UNKNOWN_READING[] ALIGN1 =
-	"error reading key '%s'";
-static const char ERR_PERMISSION_DENIED[] ALIGN1 =
-	"error: permission denied on key '%s'";
-static const char ERR_PRELOAD_FILE[] ALIGN1 =
-	"error: cannot open preload file '%s'";
-static const char WARN_BAD_LINE[] ALIGN1 =
-	"warning: %s(%d): invalid syntax, continuing";
-
-
-static void dwrite_str(int fd, const char *buf)
-{
-	write(fd, buf, strlen(buf));
-}
-
-/*
- *    sysctl_main()...
- */
-int sysctl_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int sysctl_main(int argc, char **argv)
+enum {
+	FLAG_SHOW_KEYS       = 1 << 0,
+	FLAG_SHOW_KEY_ERRORS = 1 << 1,
+	FLAG_TABLE_FORMAT    = 1 << 2, /* not implemented */
+	FLAG_SHOW_ALL        = 1 << 3,
+	FLAG_PRELOAD_FILE    = 1 << 4,
+	/* NB: procps 3.2.8 does not require -w for KEY=VAL to work, it only rejects non-KEY=VAL form */
+	FLAG_WRITE           = 1 << 5,
+	FLAG_QUIET           = 1 << 6,
+};
+#define OPTION_STR "neAapwq"
+
+static void sysctl_dots_to_slashes(char *name)
 {
-	int retval = 0;
-	int output = 1;
-	int write_mode = 0;
-	int switches_allowed = 1;
-
-	if (argc < 2)
-		bb_show_usage();
-
-	argv++;
-
-	for (; *argv /*&& **argv*/; argv++) {
-		if (switches_allowed && **argv == '-') {	/* we have a switch */
-			switch ((*argv)[1]) {
-			case 'n':
-				output = 0;
-				break;
-			case 'w':
-				write_mode = 1;
-				switches_allowed = 0;
-				break;
-			case 'p':
-				argv++;
-				return sysctl_preload_file(((*argv /*&& **argv*/) ? *argv : ETC_SYSCTL_CONF),
-							output);
-			case 'a':
-			case 'A':
-				return sysctl_display_all(PROC_SYS, output,
-							((*argv)[1] == 'A'));
-			default:
-				bb_error_msg(ERR_UNKNOWN_PARAMETER, *argv);
-				/* fall through */
-			//case 'h':
-			//case '?':
-				bb_show_usage();
+	char *cptr, *last_good, *end, *slash;
+	char end_ch;
+
+	end = strchrnul(name, '=');
+
+	slash = strchrnul(name, '/');
+	if (slash < end
+	 && strchrnul(name, '.') < slash
+	) {
+		/* There are both dots and slashes, and 1st dot is
+		 * before 1st slash.
+		 * (IOW: not raw, unmangled a/b/c.d format)
+		 *
+		 * procps supports this syntax for names with dots:
+		 *  net.ipv4.conf.eth0/100.mc_forwarding
+		 * (dots and slashes are simply swapped)
+		 */
+		while (end != name) {
+			end--;
+			if (*end == '.') *end = '/';
+			else if (*end == '/') *end = '.';
+		}
+		return;
+	}
+	/* else: use our old behavior: */
+
+	/* Convert minimum number of '.' to '/' so that
+	 * we end up with existing file's name.
+	 *
+	 * Example from bug 3894:
+	 * net.ipv4.conf.eth0.100.mc_forwarding ->
+	 * net/ipv4/conf/eth0.100/mc_forwarding
+	 * NB: net/ipv4/conf/eth0/mc_forwarding *also exists*,
+	 * therefore we must start from the end, and if
+	 * we replaced even one . -> /, start over again,
+	 * but never replace dots before the position
+	 * where last replacement occurred.
+	 *
+	 * Another bug we later had is that
+	 * net.ipv4.conf.eth0.100
+	 * (without .mc_forwarding) was mishandled.
+	 *
+	 * To set up testing: modprobe 8021q; vconfig add eth0 100
+	 */
+	end_ch = *end;
+	*end = '.'; /* trick the loop into trying full name too */
+
+	last_good = name - 1;
+ again:
+	cptr = end;
+	while (cptr > last_good) {
+		if (*cptr == '.') {
+			*cptr = '\0';
+			//bb_error_msg("trying:'%s'", name);
+			if (access(name, F_OK) == 0) {
+				*cptr = '/';
+				//bb_error_msg("replaced:'%s'", name);
+				last_good = cptr;
+				goto again;
 			}
-		} else {
-			switches_allowed = 0;
-			if (write_mode)
-				retval |= sysctl_write_setting(*argv, output);
-			else
-				sysctl_read_setting(*argv, output);
+			*cptr = '.';
 		}
+		cptr--;
 	}
-	return retval;
-} /* end sysctl_main() */
-
-/*
- * sysctl_preload_file
- * preload the sysctl's from a conf file
- * - we parse the file and then reform it (strip out whitespace)
- */
-#define PRELOAD_BUF 256
+	*end = end_ch;
+}
 
-static int sysctl_preload_file(const char *filename, int output)
+static int sysctl_act_on_setting(char *setting)
 {
-	int lineno;
-	char oneline[PRELOAD_BUF];
-	char buffer[PRELOAD_BUF];
-	char *name, *value;
-	FILE *fp;
-
-	fp = fopen(filename, "r");
-	if (fp == NULL) {
-		bb_error_msg_and_die(ERR_PRELOAD_FILE, filename);
+	int fd, retval = EXIT_SUCCESS;
+	char *cptr, *outname;
+	char *value = value; /* for compiler */
+	bool writing = (option_mask32 & FLAG_WRITE);
+
+	outname = xstrdup(setting);
+
+	cptr = outname;
+	while (*cptr) {
+		if (*cptr == '/')
+			*cptr = '.';
+		else if (*cptr == '.')
+			*cptr = '/';
+		cptr++;
 	}
 
-	lineno = 0;
-	while (fgets(oneline, sizeof(oneline) - 1, fp)) {
-		lineno++;
-		trim(oneline);
-		if (oneline[0] == '#' || oneline[0] == ';')
-			continue;
-		if (!oneline[0] || !oneline[1])
-			continue;
-
-		name = strtok(oneline, "=");
-		if (!name) {
-			bb_error_msg(WARN_BAD_LINE, filename, lineno);
-			continue;
+	cptr = strchr(setting, '=');
+	if (cptr)
+		writing = 1;
+	if (writing) {
+		if (!cptr) {
+			bb_error_msg("error: '%s' must be of the form name=value",
+				outname);
+			retval = EXIT_FAILURE;
+			goto end;
 		}
-		trim(name);
-		if (!*name) {
-			bb_error_msg(WARN_BAD_LINE, filename, lineno);
-			continue;
+		value = cptr + 1;  /* point to the value in name=value */
+		if (setting == cptr /* "name" can't be empty */
+		 /* || !*value - WRONG: "sysctl net.ipv4.ip_local_reserved_ports=" is a valid syntax (clears the value) */
+		) {
+			bb_error_msg("error: malformed setting '%s'", outname);
+			retval = EXIT_FAILURE;
+			goto end;
 		}
-
-		value = strtok(NULL, "\n\r");
-		if (!value) {
-			bb_error_msg(WARN_BAD_LINE, filename, lineno);
-			continue;
-		}
-		while (*value == ' ' || *value == '\t')
-			value++;
-		if (!*value) {
-			bb_error_msg(WARN_BAD_LINE, filename, lineno);
-			continue;
-		}
-
-		/* safe because sizeof(oneline) == sizeof(buffer) */
-		sprintf(buffer, "%s=%s", name, value);
-		sysctl_write_setting(buffer, output);
-	}
-	fclose(fp);
-	return 0;
-} /* end sysctl_preload_file() */
-
-/*
- *     Write a single sysctl setting
- */
-static int sysctl_write_setting(const char *setting, int output)
-{
-	int retval = 0;
-	const char *name;
-	const char *value;
-	const char *equals;
-	char *tmpname, *outname, *cptr;
-	int fd = -1;
-
-	name = setting;
-	equals = strchr(setting, '=');
-	if (!equals) {
-		bb_error_msg(ERR_NO_EQUALS, setting);
-		return -1;
-	}
-
-	value = equals + 1;	/* point to the value in name=value */
-	if (name == equals || !*value) {
-		bb_error_msg(ERR_MALFORMED_SETTING, setting);
-		return -2;
+		*cptr = '\0';
+		outname[cptr - setting] = '\0';
+		/* procps 3.2.7 actually uses these flags */
+		fd = open(setting, O_WRONLY|O_CREAT|O_TRUNC, 0666);
+	} else {
+		fd = open(setting, O_RDONLY);
 	}
 
-	tmpname = xasprintf("%s%.*s", PROC_SYS, (int)(equals - name), name);
-	outname = xstrdup(tmpname + strlen_PROC_SYS);
-
-	while ((cptr = strchr(tmpname, '.')) != NULL)
-		*cptr = '/';
-
-	while ((cptr = strchr(outname, '/')) != NULL)
-		*cptr = '.';
-
-	fd = open(tmpname, O_WRONLY | O_CREAT | O_TRUNC, 0666);
 	if (fd < 0) {
 		switch (errno) {
-		case ENOENT:
-			bb_error_msg(ERR_INVALID_KEY, outname);
-			break;
 		case EACCES:
-			bb_perror_msg(ERR_PERMISSION_DENIED, outname);
+			/* Happens for write-only settings, e.g. net.ipv6.route.flush */
+			goto end;
+		case ENOENT:
+			if (option_mask32 & FLAG_SHOW_KEY_ERRORS)
+				bb_error_msg("error: '%s' is an unknown key", outname);
 			break;
 		default:
-			bb_perror_msg(ERR_UNKNOWN_WRITING, outname);
+			bb_perror_msg("error %sing key '%s'",
+					writing ?
+						"sett" : "read",
+					outname);
 			break;
 		}
-		retval = -1;
+		retval = EXIT_FAILURE;
+		goto end;
+	}
+
+	if (writing) {
+//TODO: procps 3.2.7 writes "value\n", note trailing "\n"
+		xwrite_str(fd, value);
+		close(fd);
+		if (!(option_mask32 & FLAG_QUIET)) {
+			if (option_mask32 & FLAG_SHOW_KEYS)
+				printf("%s = ", outname);
+			puts(value);
+		}
 	} else {
-		dwrite_str(fd, value);
+		char c;
+
+		value = cptr = xmalloc_read(fd, NULL);
 		close(fd);
-		if (output) {
-			dwrite_str(STDOUT_FILENO, outname);
-			dwrite_str(STDOUT_FILENO, " = ");
+		if (value == NULL) {
+			bb_perror_msg("error reading key '%s'", outname);
+			retval = EXIT_FAILURE;
+			goto end;
 		}
-		dwrite_str(STDOUT_FILENO, value);
-		dwrite_str(STDOUT_FILENO, "\n");
-	}
 
-	free(tmpname);
+		/* dev.cdrom.info and sunrpc.transports, for example,
+		 * are multi-line. Try "sysctl sunrpc.transports"
+		 */
+		while ((c = *cptr) != '\0') {
+			if (option_mask32 & FLAG_SHOW_KEYS)
+				printf("%s = ", outname);
+			while (1) {
+				fputc(c, stdout);
+				cptr++;
+				if (c == '\n')
+					break;
+				c = *cptr;
+				if (c == '\0')
+					break;
+			}
+		}
+		free(value);
+	}
+ end:
 	free(outname);
 	return retval;
-} /* end sysctl_write_setting() */
+}
 
-/*
- *     Read a sysctl setting
- */
-static int sysctl_read_setting(const char *setting, int output)
+static int sysctl_act_recursive(const char *path)
 {
+	struct stat buf;
 	int retval = 0;
-	char *tmpname, *outname, *cptr;
-	char inbuf[1025];
-	const char *name;
-	FILE *fp;
-
-	if (!*setting)
-		bb_error_msg(ERR_INVALID_KEY, setting);
-
-	name = setting;
-	tmpname = concat_path_file(PROC_SYS, name);
-	outname = xstrdup(tmpname + strlen_PROC_SYS);
-
-	while ((cptr = strchr(tmpname, '.')) != NULL)
-		*cptr = '/';
-	while ((cptr = strchr(outname, '/')) != NULL)
-		*cptr = '.';
 
-	fp = fopen(tmpname, "r");
-	if (fp == NULL) {
-		switch (errno) {
-		case ENOENT:
-			bb_error_msg(ERR_INVALID_KEY, outname);
-			break;
-		case EACCES:
-			bb_error_msg(ERR_PERMISSION_DENIED, outname);
-			break;
-		default:
-			bb_perror_msg(ERR_UNKNOWN_READING, outname);
-			break;
+	if (!(option_mask32 & FLAG_WRITE)
+	 && stat(path, &buf) == 0
+	 && S_ISDIR(buf.st_mode)
+	) {
+		struct dirent *entry;
+		DIR *dirp;
+
+		dirp = opendir(path);
+		if (dirp == NULL)
+			return -1;
+		while ((entry = readdir(dirp)) != NULL) {
+			char *next = concat_subpath_file(path, entry->d_name);
+			if (next == NULL)
+				continue; /* d_name is "." or ".." */
+			/* if path was ".", drop "./" prefix: */
+			retval |= sysctl_act_recursive((next[0] == '.' && next[1] == '/') ?
+					next + 2 : next);
+			free(next);
 		}
-		retval = -1;
+		closedir(dirp);
 	} else {
-		while (fgets(inbuf, sizeof(inbuf) - 1, fp)) {
-			if (output) {
-				dwrite_str(STDOUT_FILENO, outname);
-				dwrite_str(STDOUT_FILENO, " = ");
-			}
-			dwrite_str(STDOUT_FILENO, inbuf);
-		}
-		fclose(fp);
+		char *name = xstrdup(path);
+		retval |= sysctl_act_on_setting(name);
+		free(name);
 	}
 
-	free(tmpname);
-	free(outname);
 	return retval;
-} /* end sysctl_read_setting() */
+}
 
-/*
- *     Display all the sysctl settings
+/* Set sysctl's from a conf file. Format example:
+ * # Controls IP packet forwarding
+ * net.ipv4.ip_forward = 0
  */
-static int sysctl_display_all(const char *path, int output, int show_table)
+static int sysctl_handle_preload_file(const char *filename)
 {
-	int retval = 0;
-	DIR *dp;
-	struct dirent *de;
-	char *tmpdir;
-	struct stat ts;
-
-	dp = opendir(path);
-	if (!dp) {
-		return -1;
+	char *token[2];
+	parser_t *parser;
+	int parse_flags;
+
+	parser = config_open(filename);
+	/* Must do it _after_ config_open(): */
+	xchdir("/proc/sys");
+
+	parse_flags = 0;
+	parse_flags &= ~PARSE_COLLAPSE;   // NO (var==val is not var=val) - treat consecutive delimiters as one
+	parse_flags &= ~PARSE_TRIM;       // NO - trim leading and trailing delimiters
+	parse_flags |= PARSE_GREEDY;      // YES - last token takes entire remainder of the line
+	parse_flags &= ~PARSE_MIN_DIE;    // NO - die if < min tokens found
+	parse_flags &= ~PARSE_EOL_COMMENTS; // NO (only first char) - comments are recognized even if not first char
+	parse_flags |= PARSE_ALT_COMMENTS;// YES - two comment chars: ';' and '#'
+	/* <space><tab><space>#comment is also comment, not strictly 1st char only */
+	parse_flags |= PARSE_WS_COMMENTS; // YES - comments are recognized even if there is whitespace before
+	while (config_read(parser, token, 2, 2, ";#=", parse_flags)) {
+		char *tp;
+
+		trim(token[1]);
+		tp = trim(token[0]);
+		sysctl_dots_to_slashes(token[0]);
+		/* ^^^converted in-place. tp still points to NUL */
+		/* now, add "=TOKEN1" */
+		*tp++ = '=';
+		overlapping_strcpy(tp, token[1]);
+
+		sysctl_act_on_setting(token[0]);
+	}
+	if (ENABLE_FEATURE_CLEAN_UP)
+		config_close(parser);
+	return 0;
+}
+
+int sysctl_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int sysctl_main(int argc UNUSED_PARAM, char **argv)
+{
+	int retval;
+	int opt;
+
+	opt = getopt32(argv, "+" OPTION_STR); /* '+' - stop on first non-option */
+	argv += optind;
+	opt ^= (FLAG_SHOW_KEYS | FLAG_SHOW_KEY_ERRORS);
+	option_mask32 = opt;
+
+	if (opt & FLAG_PRELOAD_FILE) {
+		int cur_dir_fd;
+		option_mask32 |= FLAG_WRITE;
+		if (!*argv)
+			*--argv = (char*)"/etc/sysctl.conf";
+		cur_dir_fd = xopen(".", O_RDONLY | O_DIRECTORY);
+		do {
+			/* xchdir("/proc/sys") is inside */
+			sysctl_handle_preload_file(*argv);
+			xfchdir(cur_dir_fd); /* files can be relative, must restore cwd */
+		} while (*++argv);
+		return 0; /* procps-ng 3.3.10 does not flag parse errors */
+	}
+	xchdir("/proc/sys");
+	if (opt & (FLAG_TABLE_FORMAT | FLAG_SHOW_ALL)) {
+		return sysctl_act_recursive(".");
+	}
+
+//TODO: if(!argv[0]) bb_show_usage() ?
+
+	retval = 0;
+	while (*argv) {
+		sysctl_dots_to_slashes(*argv);
+		retval |= sysctl_act_recursive(*argv);
+		argv++;
 	}
-	while ((de = readdir(dp)) != NULL) {
-		tmpdir = concat_subpath_file(path, de->d_name);
-		if (tmpdir == NULL)
-			continue;
-		if (stat(tmpdir, &ts) != 0) {
-			bb_perror_msg(tmpdir);
-		} else if (S_ISDIR(ts.st_mode)) {
-			sysctl_display_all(tmpdir, output, show_table);
-		} else {
-			retval |= sysctl_read_setting(tmpdir + strlen_PROC_SYS, output);
-		}
-		free(tmpdir);
-	} /* end while */
-	closedir(dp);
 
 	return retval;
-} /* end sysctl_display_all() */
+}