X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=command.c;h=5217f9b487cd260aebe5d5a986f4fd8e957b0270;hp=e6a16e53e5f3367cd9b10bf959ace284d8086ebd;hb=ab273892c54e29087d2a6b0d52de8081be1b905f;hpb=e752cdeab213b329552e1eecd5687bca512217c5;ds=sidebyside

diff --git a/command.c b/command.c
index e6a16e53..5217f9b4 100644
--- a/command.c
+++ b/command.c
@@ -1,28 +1,32 @@
 /*
- * Copyright (C) 1997-2009 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 1997-2011 Andre Noll <maan@systemlinux.org>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
 
 /** \file command.c Client authentication and server commands. */
 
+#include <regex.h>
 #include <signal.h>
 #include <sys/time.h>
 #include <sys/types.h>
 #include <dirent.h>
 #include <openssl/rc4.h>
 #include <osl.h>
+#include <stdbool.h>
 
 #include "para.h"
 #include "error.h"
+#include "crypt.h"
+#include "command.h"
 #include "server.cmdline.h"
 #include "string.h"
 #include "afh.h"
 #include "afs.h"
 #include "server.h"
-#include "vss.h"
 #include "list.h"
 #include "send.h"
+#include "vss.h"
 #include "rc4.h"
 #include "net.h"
 #include "daemon.h"
@@ -37,13 +41,12 @@
 /** Commands including options must be shorter than this. */
 #define MAX_COMMAND_LEN 32768
 
-static RC4_KEY rc4_recv_key;
-static RC4_KEY rc4_send_key;
-static unsigned char rc4_buf[2 * RC4_KEY_LEN];
-
 extern int mmd_mutex;
 extern struct misc_meta_data *mmd;
 extern struct sender senders[];
+int send_afs_status(struct rc4_context *rc4c, int parser_friendly);
+
+const char *status_item_list[] = {STATUS_ITEM_ARRAY};
 
 static void dummy(__a_unused int s)
 {
@@ -103,14 +106,15 @@ static char *vss_get_status_flags(unsigned int flags)
 	return msg;
 }
 
-static char *get_status(struct misc_meta_data *nmmd)
+static char *get_status(struct misc_meta_data *nmmd, int parser_friendly)
 {
-	char *ret, mtime[30] = "";
+	char mtime[30] = "";
 	char *status, *flags; /* vss status info */
 	char *ut = uptime_str();
 	long offset = (nmmd->offset + 500) / 1000;
 	struct timeval current_time;
 	struct tm mtime_tm;
+	struct para_buffer b = {.flags = parser_friendly? PBF_SIZE_PREFIX : 0};
 
 	/* report real status */
 	status = vss_status_tohuman(nmmd->vss_status_flags);
@@ -120,34 +124,22 @@ static char *get_status(struct misc_meta_data *nmmd)
 		strftime(mtime, 29, "%b %d %Y", &mtime_tm);
 	}
 	gettimeofday(&current_time, NULL);
-	ret = make_message(
-		"%s: %zu\n" /* file size */
-		"%s: %s\n" /* mtime */
-		"%s: %s\n" /* status */
-		"%s: %s\n" /* status flags */
-		"%s: %li\n" /* offset */
-		"%s: %s\n" /* afs mode */
-		"%s: %lu.%lu\n" /* stream start */
-		"%s: %lu.%lu\n", /* current server time */
-		status_item_list[SI_FILE_SIZE], nmmd->size / 1024,
-		status_item_list[SI_MTIME], mtime,
-		status_item_list[SI_STATUS], status,
-		status_item_list[SI_STATUS_FLAGS], flags,
-
-		status_item_list[SI_OFFSET], offset,
-		status_item_list[SI_AFS_MODE], mmd->afs_mode_string,
-
-		status_item_list[SI_STREAM_START],
-			(long unsigned)nmmd->stream_start.tv_sec,
-			(long unsigned)nmmd->stream_start.tv_usec,
-		status_item_list[SI_CURRENT_TIME],
-			(long unsigned)current_time.tv_sec,
-			(long unsigned)current_time.tv_usec
-	);
+	WRITE_STATUS_ITEM(&b, SI_FILE_SIZE, "%zu\n", nmmd->size / 1024);
+	WRITE_STATUS_ITEM(&b, SI_MTIME, "%s\n", mtime);
+	WRITE_STATUS_ITEM(&b, SI_STATUS, "%s\n", status);
+	WRITE_STATUS_ITEM(&b, SI_STATUS_FLAGS, "%s\n", flags);
+	WRITE_STATUS_ITEM(&b, SI_OFFSET, "%li\n", offset);
+	WRITE_STATUS_ITEM(&b, SI_AFS_MODE, "%s\n", mmd->afs_mode_string);
+	WRITE_STATUS_ITEM(&b, SI_STREAM_START, "%lu.%lu\n",
+		(long unsigned)nmmd->stream_start.tv_sec,
+		(long unsigned)nmmd->stream_start.tv_usec);
+	WRITE_STATUS_ITEM(&b, SI_CURRENT_TIME, "%lu.%lu\n",
+		(long unsigned)current_time.tv_sec,
+		(long unsigned)current_time.tv_usec);
 	free(flags);
 	free(status);
 	free(ut);
-	return ret;
+	return b.buf;
 }
 
 static int check_sender_args(int argc, char * const * argv, struct sender_command_data *scd)
@@ -182,17 +174,9 @@ static int check_sender_args(int argc, char * const * argv, struct sender_comman
 		break;
 	case SENDER_DENY:
 	case SENDER_ALLOW:
-		if (argc != 4 && argc != 5)
-			return -E_COMMAND_SYNTAX;
-		if (!is_valid_ipv4_address(argv[3]))
+		if (argc != 4 || parse_cidr(argv[3], scd->host,
+				sizeof(scd->host), &scd->netmask) == NULL)
 			return -E_COMMAND_SYNTAX;
-		scd->netmask = 32;
-		if (argc == 5) {
-			scd->netmask = atoi(argv[4]);
-			if (scd->netmask < 0 || scd->netmask > 32)
-				return -E_COMMAND_SYNTAX;
-		}
-		strncpy(scd->host, argv[3], sizeof(scd->host));
 		break;
 	case SENDER_ADD:
 	case SENDER_DELETE:
@@ -205,33 +189,42 @@ static int check_sender_args(int argc, char * const * argv, struct sender_comman
 	return 1;
 }
 
-int com_sender(int fd, int argc, char * const * argv)
+int com_sender(struct rc4_context *rc4c, int argc, char * const * argv)
 {
 	int i, ret;
+	char *msg = NULL;
 	struct sender_command_data scd;
 
 	if (argc < 2) {
-		char *msg = NULL;
 		for (i = 0; senders[i].name; i++) {
 			char *tmp = make_message("%s%s\n",
 				msg? msg : "", senders[i].name);
 			free(msg);
 			msg = tmp;
 		}
-		ret = send_buffer(fd, msg);
+		ret = rc4_send_buffer(rc4c, msg);
 		free(msg);
 		return ret;
 	}
 	ret = check_sender_args(argc, argv, &scd);
 	if (ret < 0) {
-		char *msg;
 		if (scd.sender_num < 0)
 			return ret;
 		msg = senders[scd.sender_num].help();
-		ret = send_buffer(fd, msg);
+		ret = rc4_send_buffer(rc4c, msg);
 		free(msg);
 		return ret;
 	}
+
+	switch (scd.cmd_num) {
+	case SENDER_ADD:
+	case SENDER_DELETE:
+		assert(senders[scd.sender_num].resolve_target);
+		ret = senders[scd.sender_num].resolve_target(argv[3], &scd);
+		if (ret < 0)
+			return ret;
+	}
+
 	for (i = 0; i < 10; i++) {
 		mutex_lock(mmd_mutex);
 		if (mmd->sender_cmd_data.cmd_num >= 0) {
@@ -247,11 +240,11 @@ int com_sender(int fd, int argc, char * const * argv)
 }
 
 /* server info */
-int com_si(int fd, int argc, __a_unused char * const * argv)
+int com_si(struct rc4_context *rc4c, int argc, __a_unused char * const * argv)
 {
 	int i, ret;
 	char *ut;
-	char *sender_info = NULL, *sender_list = NULL;
+	char *sender_info = NULL;
 
 	if (argc != 1)
 		return -E_COMMAND_SYNTAX;
@@ -260,17 +253,15 @@ int com_si(int fd, int argc, __a_unused char * const * argv)
 		char *info = senders[i].info();
 		sender_info = para_strcat(sender_info, info);
 		free(info);
-		sender_list = para_strcat(sender_list, senders[i].name);
-		sender_list = para_strcat(sender_list, " ");
 	}
 	ut = uptime_str();
-	ret = send_va_buffer(fd, "up: %s\nplayed: %u\n"
+	ret = rc4_send_va_buffer(rc4c, "version: " GIT_VERSION "\n"
+		"up: %s\nplayed: %u\n"
 		"server_pid: %d\n"
 		"afs_pid: %d\n"
 		"connections (active/accepted/total): %u/%u/%u\n"
 		"current loglevel: %s\n"
 		"supported audio formats: %s\n"
-		"supported senders: %s\n"
 		"%s",
 		ut, mmd->num_played,
 		(int)getppid(),
@@ -279,122 +270,130 @@ int com_si(int fd, int argc, __a_unused char * const * argv)
 		mmd->num_commands,
 		mmd->num_connects,
 		conf.loglevel_arg,
-		supported_audio_formats(),
-		sender_list,
+		SERVER_AUDIO_FORMATS,
 		sender_info
 	);
 	mutex_unlock(mmd_mutex);
 	free(ut);
-	free(sender_list);
 	free(sender_info);
 	return ret;
 }
 
 /* version */
-int com_version(int fd, int argc, __a_unused char * const * argv)
+int com_version(struct rc4_context *rc4c, int argc, __a_unused char * const * argv)
 {
 	if (argc != 1)
 		return -E_COMMAND_SYNTAX;
-	return send_buffer(fd, VERSION_TEXT("server")
+	return rc4_send_buffer(rc4c, VERSION_TEXT("server")
 		"built: " BUILD_DATE "\n"
 		UNAME_RS ", " CC_VERSION "\n"
 	);
 }
 
+#define EMPTY_STATUS_ITEMS \
+	ITEM(PATH) \
+	ITEM(DIRECTORY) \
+	ITEM(BASENAME) \
+	ITEM(SCORE) \
+	ITEM(ATTRIBUTES_BITMAP) \
+	ITEM(ATTRIBUTES_TXT) \
+	ITEM(HASH) \
+	ITEM(IMAGE_ID) \
+	ITEM(IMAGE_NAME) \
+	ITEM(LYRICS_ID) \
+	ITEM(LYRICS_NAME) \
+	ITEM(BITRATE) \
+	ITEM(FORMAT) \
+	ITEM(FREQUENCY) \
+	ITEM(CHANNELS) \
+	ITEM(DURATION) \
+	ITEM(SECONDS_TOTAL) \
+	ITEM(NUM_PLAYED) \
+	ITEM(LAST_PLAYED) \
+	ITEM(TECHINFO) \
+	ITEM(ARTIST) \
+	ITEM(TITLE) \
+	ITEM(YEAR) \
+	ITEM(ALBUM) \
+	ITEM(COMMENT) \
+	ITEM(AMPLIFICATION)
+
 /**
  * Write a list of audio-file related status items with empty values.
  *
  * This is used by vss when currently no audio file is open.
  */
-static char *empty_status_items(void)
-{
+static char *empty_status_items(int parser_friendly)
+{
+	if (parser_friendly)
+		return make_message(
+			#define ITEM(x) "0004 %02x:\n"
+			EMPTY_STATUS_ITEMS
+			#undef ITEM
+			#define ITEM(x) , SI_ ## x
+			EMPTY_STATUS_ITEMS
+			#undef ITEM
+		);
 	return make_message(
-		"%s: \n" /* path */
-		"%s: \n" /* dirname */
-		"%s: \n" /* basename */
-		"%s: \n" /* score */
-		"%s: \n" /* attributes bitmap */
-		"%s: \n" /* attributes txt */
-		"%s: \n" /* hash */
-		"%s: \n" /* image id */
-		"%s: \n" /* image name */
-		"%s: \n" /* lyrics id */
-		"%s: \n" /* lyrics name */
-		"%s: \n" /* bitrate */
-		"%s: \n" /* format */
-		"%s: \n" /* frequency */
-		"%s: \n" /* channels */
-		"%s: \n" /* duration */
-		"%s: \n" /* seconds total */
-		"%s: \n" /* num played */
-		"%s: \n" /* last played */
-		"%s: \n" /* techinfo */
-		"%s: \n" /* artist */
-		"%s: \n" /* title */
-		"%s: \n" /* year */
-		"%s: \n" /* album */
-		"%s: \n" /* comment */
-		"%s: \n" /* amplification */
-		,
-		status_item_list[SI_PATH],
-		status_item_list[SI_DIRECTORY],
-		status_item_list[SI_BASENAME],
-		status_item_list[SI_SCORE],
-		status_item_list[SI_ATTRIBUTES_BITMAP],
-		status_item_list[SI_ATTRIBUTES_TXT],
-		status_item_list[SI_HASH],
-		status_item_list[SI_IMAGE_ID],
-		status_item_list[SI_IMAGE_NAME],
-		status_item_list[SI_LYRICS_ID],
-		status_item_list[SI_LYRICS_NAME],
-		status_item_list[SI_BITRATE],
-		status_item_list[SI_FORMAT],
-		status_item_list[SI_FREQUENCY],
-		status_item_list[SI_CHANNELS],
-		status_item_list[SI_DURATION],
-		status_item_list[SI_SECONDS_TOTAL],
-		status_item_list[SI_NUM_PLAYED],
-		status_item_list[SI_LAST_PLAYED],
-		status_item_list[SI_TECHINFO],
-		status_item_list[SI_ARTIST],
-		status_item_list[SI_TITLE],
-		status_item_list[SI_YEAR],
-		status_item_list[SI_ALBUM],
-		status_item_list[SI_COMMENT],
-		status_item_list[SI_AMPLIFICATION]
+		#define ITEM(x) "%s:\n"
+		EMPTY_STATUS_ITEMS
+		#undef ITEM
+		#define ITEM(x) ,status_item_list[SI_ ## x]
+		EMPTY_STATUS_ITEMS
+		#undef ITEM
 	);
 }
+#undef EMPTY_STATUS_ITEMS
 
 /* stat */
-int com_stat(int fd, int argc, char * const * argv)
+int com_stat(struct rc4_context *rc4c, int argc, char * const * argv)
 {
-	int ret, num = 0;/* status will be printed that many
-			  * times. num <= 0 means: print forever
-			  */
+	int i, ret;
 	struct misc_meta_data tmp, *nmmd = &tmp;
 	char *s;
+	int32_t num = 0;
+	int parser_friendly = 0;
 
 	para_sigaction(SIGUSR1, dummy);
 
-	if (argc > 1)
-		num = atoi(argv[1]);
+	for (i = 1; i < argc; i++) {
+		const char *arg = argv[i];
+		if (arg[0] != '-')
+			break;
+		if (!strcmp(arg, "--")) {
+			i++;
+			break;
+		}
+		if (!strncmp(arg, "-n=", 3)) {
+			ret = para_atoi32(arg + 3, &num);
+			if (ret < 0)
+				return ret;
+			continue;
+		}
+		if (!strcmp(arg, "-p")) {
+			parser_friendly = 1;
+			continue;
+		}
+		return -E_COMMAND_SYNTAX;
+	}
+	if (i != argc)
+		return -E_COMMAND_SYNTAX;
 	for (;;) {
-
 		mmd_dup(nmmd);
-		s = get_status(nmmd);
-		ret = send_buffer(fd, s);
+		s = get_status(nmmd, parser_friendly);
+		ret = rc4_send_buffer(rc4c, s);
 		free(s);
 		if (ret < 0)
 			goto out;
 		if (nmmd->vss_status_flags & VSS_NEXT) {
 			static char *esi;
 			if (!esi)
-				esi = empty_status_items();
-			ret = send_buffer(fd, esi);
+				esi = empty_status_items(parser_friendly);
+			ret = rc4_send_buffer(rc4c, esi);
 			if (ret < 0)
 				goto out;
 		} else
-			send_afs_status(fd);
+			send_afs_status(rc4c, parser_friendly);
 		ret = 1;
 		if (num > 0 && !--num)
 			goto out;
@@ -406,14 +405,14 @@ out:
 	return ret;
 }
 
-static int send_list_of_commands(int fd, struct server_command *cmd,
+static int send_list_of_commands(struct rc4_context *rc4c, struct server_command *cmd,
 		const char *handler)
 {
 	int ret, i;
 
 	for (i = 1; cmd->name; cmd++, i++) {
 		char *perms = cmd_perms_itohuman(cmd->perms);
-		ret = send_va_buffer(fd, "%s\t%s\t%s\t%s\n", cmd->name,
+		ret = rc4_send_va_buffer(rc4c, "%s\t%s\t%s\t%s\n", cmd->name,
 			handler,
 			perms,
 			cmd->description);
@@ -446,7 +445,7 @@ static struct server_command *get_cmd_ptr(const char *name, char **handler)
 }
 
 /* help */
-int com_help(int fd, int argc, char * const * argv)
+int com_help(struct rc4_context *rc4c, int argc, char * const * argv)
 {
 	struct server_command *cmd;
 	char *perms, *handler;
@@ -454,18 +453,16 @@ int com_help(int fd, int argc, char * const * argv)
 
 	if (argc < 2) {
 		/* no argument given, print list of commands */
-		if ((ret = send_list_of_commands(fd, server_cmds, "server")) < 0)
+		if ((ret = send_list_of_commands(rc4c, server_cmds, "server")) < 0)
 			return ret;
-		return send_list_of_commands(fd, afs_cmds, "afs");
+		return send_list_of_commands(rc4c, afs_cmds, "afs");
 	}
 	/* argument given for help */
 	cmd = get_cmd_ptr(argv[1], &handler);
-	if (!cmd) {
-		free(handler);
+	if (!cmd)
 		return -E_BAD_CMD;
-	}
 	perms = cmd_perms_itohuman(cmd->perms);
-	ret = send_va_buffer(fd,
+	ret = rc4_send_va_buffer(rc4c,
 		"%s - %s\n\n"
 		"handler: %s\n"
 		"permissions: %s\n"
@@ -484,7 +481,7 @@ int com_help(int fd, int argc, char * const * argv)
 }
 
 /* hup */
-int com_hup(__a_unused int fd, int argc, __a_unused char * const * argv)
+int com_hup(__a_unused struct rc4_context *rc4c, int argc, __a_unused char * const * argv)
 {
 	if (argc != 1)
 		return -E_COMMAND_SYNTAX;
@@ -493,7 +490,7 @@ int com_hup(__a_unused int fd, int argc, __a_unused char * const * argv)
 }
 
 /* term */
-int com_term(__a_unused int fd, int argc, __a_unused char * const * argv)
+int com_term(__a_unused struct rc4_context *rc4c, int argc, __a_unused char * const * argv)
 {
 	if (argc != 1)
 		return -E_COMMAND_SYNTAX;
@@ -501,7 +498,7 @@ int com_term(__a_unused int fd, int argc, __a_unused char * const * argv)
 	return 1;
 }
 
-int com_play(__a_unused int fd, int argc, __a_unused char * const * argv)
+int com_play(__a_unused struct rc4_context *rc4c, int argc, __a_unused char * const * argv)
 {
 	if (argc != 1)
 		return -E_COMMAND_SYNTAX;
@@ -514,7 +511,7 @@ int com_play(__a_unused int fd, int argc, __a_unused char * const * argv)
 }
 
 /* stop */
-int com_stop(__a_unused int fd, int argc, __a_unused char * const * argv)
+int com_stop(__a_unused struct rc4_context *rc4c, int argc, __a_unused char * const * argv)
 {
 	if (argc != 1)
 		return -E_COMMAND_SYNTAX;
@@ -527,7 +524,7 @@ int com_stop(__a_unused int fd, int argc, __a_unused char * const * argv)
 }
 
 /* pause */
-int com_pause(__a_unused int fd, int argc, __a_unused char * const * argv)
+int com_pause(__a_unused struct rc4_context *rc4c, int argc, __a_unused char * const * argv)
 {
 	if (argc != 1)
 		return -E_COMMAND_SYNTAX;
@@ -542,7 +539,7 @@ int com_pause(__a_unused int fd, int argc, __a_unused char * const * argv)
 }
 
 /* next */
-int com_next(__a_unused int fd, int argc, __a_unused char * const * argv)
+int com_next(__a_unused struct rc4_context *rc4c, int argc, __a_unused char * const * argv)
 {
 	if (argc != 1)
 		return -E_COMMAND_SYNTAX;
@@ -554,7 +551,7 @@ int com_next(__a_unused int fd, int argc, __a_unused char * const * argv)
 }
 
 /* nomore */
-int com_nomore(__a_unused int fd, int argc, __a_unused char * const * argv)
+int com_nomore(__a_unused struct rc4_context *rc4c, int argc, __a_unused char * const * argv)
 {
 	if (argc != 1)
 		return -E_COMMAND_SYNTAX;
@@ -566,7 +563,7 @@ int com_nomore(__a_unused int fd, int argc, __a_unused char * const * argv)
 }
 
 /* ff */
-int com_ff(__a_unused int fd, int argc, char * const * argv)
+int com_ff(__a_unused struct rc4_context *rc4c, int argc, char * const * argv)
 {
 	long promille;
 	int ret, backwards = 0;
@@ -605,7 +602,7 @@ out:
 }
 
 /* jmp */
-int com_jmp(__a_unused int fd, int argc, char * const * argv)
+int com_jmp(__a_unused struct rc4_context *rc4c, int argc, char * const * argv)
 {
 	long unsigned int i;
 	int ret;
@@ -659,32 +656,7 @@ static struct server_command *parse_cmd(const char *cmdstr)
 	return get_cmd_ptr(buf, NULL);
 }
 
-static void init_rc4_keys(void)
-{
-	int i;
-
-	for (i = 0; i < 2 * RC4_KEY_LEN; i++)
-		rc4_buf[i] = para_random(256);
-	PARA_DEBUG_LOG("rc4 keys initialized (%u:%u)\n",
-		(unsigned char) rc4_buf[0],
-		(unsigned char) rc4_buf[RC4_KEY_LEN]);
-	RC4_set_key(&rc4_recv_key, RC4_KEY_LEN, rc4_buf);
-	RC4_set_key(&rc4_send_key, RC4_KEY_LEN, rc4_buf + RC4_KEY_LEN);
-}
-
-static void rc4_recv(unsigned long len, const unsigned char *indata,
-		unsigned char *outdata, __a_unused void *private_data)
-{
-	RC4(&rc4_recv_key, len, indata, outdata);
-}
-
-static void rc4_send(unsigned long len, const unsigned char *indata,
-		unsigned char *outdata, __a_unused void *private_data)
-{
-	RC4(&rc4_send_key, len, indata, outdata);
-}
-
-static int read_command(int fd, char **result)
+static int read_command(struct rc4_context *rc4c, char **result)
 {
 	int ret;
 	char buf[4096];
@@ -694,7 +666,7 @@ static int read_command(int fd, char **result)
 		size_t numbytes;
 		char *p;
 
-		ret = recv_buffer(fd, buf, sizeof(buf));
+		ret = rc4_recv_buffer(rc4c, buf, sizeof(buf));
 		if (ret < 0)
 			goto out;
 		if (!ret)
@@ -757,90 +729,94 @@ static void reset_signals(void)
  */
 __noreturn void handle_connect(int fd, const char *peername)
 {
-	int ret, argc, use_rc4 = 0;
+	int ret, argc;
 	char buf[4096];
-	unsigned char crypt_buf[MAXLINE];
+	unsigned char rand_buf[CHALLENGE_SIZE + 2 * RC4_KEY_LEN];
+	unsigned char challenge_sha1[HASH_SIZE];
 	struct user *u;
 	struct server_command *cmd = NULL;
-	long unsigned challenge_nr, chall_response;
 	char **argv = NULL;
 	char *p, *command = NULL;
 	size_t numbytes;
+	struct rc4_context rc4c = {.fd = fd};
 
 	reset_signals();
 	/* we need a blocking fd here as recv() might return EAGAIN otherwise. */
 	ret = mark_fd_blocking(fd);
 	if (ret < 0)
-		goto err_out;
-	challenge_nr = random();
+		goto net_err;
 	/* send Welcome message */
 	ret = send_va_buffer(fd, "This is para_server, version "
 		PACKAGE_VERSION  ".\n" );
 	if (ret < 0)
-		goto err_out;
+		goto net_err;
 	/* recv auth request line */
 	ret = recv_buffer(fd, buf, sizeof(buf));
 	if (ret < 0)
-		goto err_out;
-	if (ret <= 6) {
-		ret = -E_AUTH;
-		goto err_out;
+		goto net_err;
+	if (ret < 10) {
+		ret = -E_AUTH_REQUEST;
+		goto net_err;
 	}
 	numbytes = ret;
-	ret = -E_AUTH;
-	if (strncmp(buf, "auth ", 5))
-		goto err_out;
-
-	if (numbytes < 9 || strncmp(buf, "auth rc4 ", 9))
-		p = buf + 5; /* client version < 0.2.6 */
-	else {
-		p = buf + 9; /* client version >= 0.2.6 */
-		use_rc4 = 1;
-	}
-	PARA_DEBUG_LOG("received %s request for user %s\n",
-		use_rc4? "rc4" : "auth", p);
+	ret = -E_AUTH_REQUEST;
+	if (strncmp(buf, AUTH_REQUEST_MSG, strlen(AUTH_REQUEST_MSG)))
+		goto net_err;
+	p = buf + strlen(AUTH_REQUEST_MSG);
+	PARA_DEBUG_LOG("received auth request for user %s\n", p);
 	ret = -E_BAD_USER;
 	u = lookup_user(p);
-	if (!u)
-		goto err_out;
-	ret = para_encrypt_challenge(u->rsa, challenge_nr, crypt_buf);
-	if (ret <= 0)
-		goto err_out;
-	numbytes = ret;
-	PARA_DEBUG_LOG("sending %zu byte challenge\n", numbytes);
-	/* We can't use send_buffer here since buf may contain null bytes */
-	ret = send_bin_buffer(fd,(char *) crypt_buf, numbytes);
+	if (u) {
+		get_random_bytes_or_die(rand_buf, sizeof(rand_buf));
+		ret = para_encrypt_buffer(u->rsa, rand_buf, sizeof(rand_buf),
+			(unsigned char *)buf);
+		if (ret < 0)
+			goto net_err;
+		numbytes = ret;
+	} else {
+		/*
+		 * We don't want to reveal our user names, so we send a
+		 * challenge to the client even if the user does not exist, and
+		 * fail the authentication later.
+		 */
+		numbytes = 256;
+		get_random_bytes_or_die((unsigned char *)buf, numbytes);
+	}
+	PARA_DEBUG_LOG("sending %u byte challenge + rc4 keys (%zu bytes)\n",
+		CHALLENGE_SIZE, numbytes);
+	ret = send_bin_buffer(fd, buf, numbytes);
 	if (ret < 0)
 		goto net_err;
-	/* recv decrypted number */
-	ret = recv_buffer(fd, buf, sizeof(buf));
+	/* recv challenge response */
+	ret = recv_bin_buffer(fd, buf, HASH_SIZE);
 	if (ret < 0)
 		goto net_err;
 	numbytes = ret;
-	ret = -E_AUTH;
-	if (!numbytes)
+	PARA_DEBUG_LOG("received %d bytes challenge response\n", ret);
+	ret = -E_BAD_USER;
+	if (!u)
 		goto net_err;
-	if (sscanf(buf, CHALLENGE_RESPONSE_MSG "%lu", &chall_response) < 1
-			|| chall_response != challenge_nr)
-		goto err_out;
-	/* auth successful, send 'Proceed' message */
-	PARA_INFO_LOG("good auth for %s (%lu)\n", u->name, challenge_nr);
-	sprintf(buf, "%s", PROCEED_MSG);
-	if (use_rc4) {
-		init_rc4_keys();
-		ret = para_encrypt_buffer(u->rsa, rc4_buf, 2 * RC4_KEY_LEN,
-			(unsigned char *)buf + PROCEED_MSG_LEN + 1);
-		if (ret <= 0)
-			goto err_out;
-		numbytes = ret + strlen(PROCEED_MSG) + 1;
-	} else
-		numbytes = strlen(buf);
-	ret = send_bin_buffer(fd, buf, numbytes);
+	/*
+	 * The correct response is the sha1 of the first CHALLENGE_SIZE bytes
+	 * of the random data.
+	 */
+	ret = -E_BAD_AUTH;
+	if (numbytes != HASH_SIZE)
+		goto net_err;
+	sha1_hash((char *)rand_buf, CHALLENGE_SIZE, challenge_sha1);
+	if (memcmp(challenge_sha1, buf, HASH_SIZE))
+		goto net_err;
+	/* auth successful */
+	alarm(0);
+	PARA_INFO_LOG("good auth for %s\n", u->name);
+	/* init rc4 keys with the second part of the random buffer */
+	RC4_set_key(&rc4c.recv_key, RC4_KEY_LEN, rand_buf + CHALLENGE_SIZE);
+	RC4_set_key(&rc4c.send_key, RC4_KEY_LEN, rand_buf + CHALLENGE_SIZE
+		+ RC4_KEY_LEN);
+	ret = rc4_send_buffer(&rc4c, PROCEED_MSG);
 	if (ret < 0)
 		goto net_err;
-	if (use_rc4)
-		enable_crypt(fd, rc4_recv, rc4_send, NULL);
-	ret = read_command(fd, &command);
+	ret = read_command(&rc4c, &command);
 	if (ret == -E_COMMAND_SYNTAX)
 		goto err_out;
 	if (ret < 0)
@@ -854,23 +830,25 @@ __noreturn void handle_connect(int fd, const char *peername)
 	if (ret < 0)
 		goto err_out;
 	/* valid command and sufficient perms */
-	alarm(0);
-	argc = split_args(command, &argv, "\n");
+	ret = create_argv(command, "\n", &argv);
+	if (ret < 0)
+		goto err_out;
+	argc = ret;
 	PARA_NOTICE_LOG("calling com_%s() for %s@%s\n", cmd->name, u->name,
 			peername);
-	ret = cmd->handler(fd, argc, argv);
+	ret = cmd->handler(&rc4c, argc, argv);
+	free_argv(argv);
 	mutex_lock(mmd_mutex);
 	mmd->num_commands++;
 	mutex_unlock(mmd_mutex);
 	if (ret >= 0)
 		goto out;
 err_out:
-	send_va_buffer(fd, "%s\n", para_strerror(-ret));
+	rc4_send_va_buffer(&rc4c, "%s\n", para_strerror(-ret));
 net_err:
 	PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
 out:
 	free(command);
-	free(argv);
 	mutex_lock(mmd_mutex);
 	if (cmd && (cmd->perms & AFS_WRITE) && ret >= 0)
 		mmd->events++;