/*
* Copyright (C) 1997-2007 Andre Noll <maan@systemlinux.org>
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
+ * Licensed under the GPL v2. For licencing details see COPYING.
*/
/** \file command.c does client authentication and executes server commands */
#include <sys/time.h> /* gettimeofday */
#include "server.cmdline.h"
-#include "db.h"
+#include "afs.h"
#include "server.h"
#include "vss.h"
#include "send.h"
#include "user_list.h"
#include "server_command_list.h"
+/** commands including options must be shorter than this */
+#define MAX_COMMAND_LEN 4096
+
static RC4_KEY rc4_recv_key;
static RC4_KEY rc4_send_key;
static unsigned char rc4_buf[2 * RC4_KEY_LEN];
extern struct misc_meta_data *mmd;
extern struct audio_file_selector selectors[];
extern struct sender senders[];
-extern char *user_list;
-struct sockaddr_in *in_addr;
static void dummy(__a_unused int s)
{}
/*
* return human readable permission string. Never returns NULL.
*/
-char *cmd_perms_itohuman(unsigned int perms)
+static char *cmd_perms_itohuman(unsigned int perms)
{
char *msg = para_malloc(5 * sizeof(char));
- msg[0] = perms & DB_READ? 'a' : '-';
- msg[1] = perms & DB_WRITE? 'A' : '-';
+ msg[0] = perms & AFS_READ? 'a' : '-';
+ msg[1] = perms & AFS_WRITE? 'A' : '-';
msg[2] = perms & VSS_READ? 'v' : '-';
msg[3] = perms & VSS_WRITE? 'V' : '-';
msg[4] = '\0';
/*
* compute status bar string. Never returns NULL
*/
-char *get_sb_string(struct misc_meta_data *nmmd)
+static char *get_sb_string(struct misc_meta_data *nmmd)
{
char *base, *ret;
long long unsigned secs = 0, rsecs = 0, percent = 0;
return para_strdup("");
if (!base[0])
return base;
- if (nmmd->chunks_total) {
- secs = (long long) nmmd->seconds_total * nmmd->chunks_sent
- / nmmd->chunks_total;
- rsecs = (long long) nmmd->seconds_total *
- (nmmd->chunks_total - nmmd->chunks_sent)
- / nmmd->chunks_total;
+ if (nmmd->afi.chunks_total) {
+ secs = (long long) nmmd->afi.seconds_total * nmmd->chunks_sent
+ / nmmd->afi.chunks_total;
+ rsecs = (long long) nmmd->afi.seconds_total *
+ (nmmd->afi.chunks_total - nmmd->chunks_sent)
+ / nmmd->afi.chunks_total;
percent = 100 * ((nmmd->chunks_sent + 5) / 10)
- / ((nmmd->chunks_total + 5) / 10);
+ / ((nmmd->afi.chunks_total + 5) / 10);
}
ret = make_message("%llu:%02llu [%llu:%02llu] (%llu%%) %s",
secs / 60, secs % 60,
bar = para_basename(nmmd->filename);
gettimeofday(&now, NULL);
ret = make_message(
- "%s:%lu\n" "%s:%s\n" "%s:%i\n" "%s:%u\n"
+ "%s:%zu\n" "%s:%s\n" "%s:%lu\n" "%s:%u\n"
"%s:%s\n" "%s:%s\n" "%s:%s\n" "%s:%s\n"
"%s:%li\n" "%s:%s\n" "%s" "%s"
"%s:%s\n" "%s:%lu.%lu\n" "%s:%lu.%lu\n",
status_item_list[SI_FILE_SIZE], nmmd->size / 1024,
status_item_list[SI_MTIME], mtime,
- status_item_list[SI_LENGTH], nmmd->seconds_total,
+ status_item_list[SI_LENGTH], nmmd->afi.seconds_total,
status_item_list[SI_NUM_PLAYED], nmmd->num_played,
status_item_list[SI_STATUS_BAR], bar ? bar : "(none)",
status_item_list[SI_OFFSET], offset,
status_item_list[SI_FORMAT], audio_format_name(nmmd->audio_format),
nmmd->selector_info,
- nmmd->audio_file_info,
+ nmmd->afi.info_string,
status_item_list[SI_UPTIME], ut,
status_item_list[SI_STREAM_START],
}
/* version */
-int com_version(int socket_fd, int argc, __a_unused char **argv)
+int com_version(int fd, int argc, __a_unused char **argv)
{
if (argc != 1)
return -E_COMMAND_SYNTAX;
- return send_buffer(socket_fd, "para_server-" PACKAGE_VERSION ", \""
- CODENAME "\"\n"
- COPYRIGHT "\n"
- "built: " BUILD_DATE "\n"
- SYSTEM ", " CC_VERSION "\n"
- );
+ return send_buffer(fd, VERSION_TEXT("server")
+ "built: " BUILD_DATE "\n"
+ SYSTEM ", " CC_VERSION "\n"
+ );
}
/* sc */
-int com_sc(int socket_fd, int argc, char **argv)
+int com_sc(int fd, int argc, char **argv)
{
char *name = NULL;
int ret, old = 0, count = -1; /* print af change forever */
}
mmd_unlock();
if (name) {
- ret = send_va_buffer(socket_fd, "%s\n", name);
+ ret = send_va_buffer(fd, "%s\n", name);
free(name);
name = NULL;
if (ret < 0)
}
/* sb */
-int com_sb(int socket_fd, int argc, char **argv)
+int com_sb(int fd, int argc, char **argv)
{
char *sb;
int ret, nr = -1; /* status bar will be printed that many
mmd_lock();
sb = get_sb_string(mmd);
mmd_unlock();
- ret = send_va_buffer(socket_fd, "%s\n", sb);
+ ret = send_va_buffer(fd, "%s\n", sb);
free(sb);
if (ret < 0)
return ret;
}
/* stat */
-int com_stat(int socket_fd, int argc, char **argv)
+int com_stat(int fd, int argc, char **argv)
{
int ret, num = 0;/* status will be printed that many
* times. num <= 0 means: print forever
mmd_dup(nmmd);
s = get_status(nmmd);
- ret = send_buffer(socket_fd, s);
+ ret = send_buffer(fd, s);
free(s);
if (ret < 0)
goto out;
}
/* hup */
-int com_hup(__a_unused int socket_fd, int argc, __a_unused char **argv)
+int com_hup(__a_unused int fd, int argc, __a_unused char **argv)
{
if (argc != 1)
return -E_COMMAND_SYNTAX;
}
/* term */
-int com_term(__a_unused int socket_fd, int argc, __a_unused char **argv)
+int com_term(__a_unused int fd, int argc, __a_unused char **argv)
{
if (argc != 1)
return -E_COMMAND_SYNTAX;
return 1;
}
-int com_play(__a_unused int socket_fd, int argc, __a_unused char **argv)
+int com_play(__a_unused int fd, int argc, __a_unused char **argv)
{
if (argc != 1)
return -E_COMMAND_SYNTAX;
}
/* stop */
-int com_stop(__a_unused int socket_fd, int argc, __a_unused char **argv)
+int com_stop(__a_unused int fd, int argc, __a_unused char **argv)
{
if (argc != 1)
return -E_COMMAND_SYNTAX;
}
/* pause */
-int com_pause(__a_unused int socket_fd, int argc, __a_unused char **argv)
+int com_pause(__a_unused int fd, int argc, __a_unused char **argv)
{
if (argc != 1)
return -E_COMMAND_SYNTAX;
}
/* next */
-int com_next(__a_unused int socket_fd, int argc, __a_unused char **argv)
+int com_next(__a_unused int fd, int argc, __a_unused char **argv)
{
if (argc != 1)
return -E_COMMAND_SYNTAX;
}
/* nomore */
-int com_nomore(__a_unused int socket_fd, int argc, __a_unused char **argv)
+int com_nomore(__a_unused int fd, int argc, __a_unused char **argv)
{
if (argc != 1)
return -E_COMMAND_SYNTAX;
}
/* ff */
-int com_ff(__a_unused int socket_fd, int argc, char **argv)
+int com_ff(__a_unused int fd, int argc, char **argv)
{
long promille;
int ret, backwards = 0;
backwards = 1; /* jmp backwards */
mmd_lock();
ret = -E_NO_AUDIO_FILE;
- if (!mmd->chunks_total || !mmd->seconds_total)
+ if (!mmd->afi.chunks_total || !mmd->afi.seconds_total)
goto out;
- promille = (1000 * mmd->current_chunk) / mmd->chunks_total;
+ promille = (1000 * mmd->current_chunk) / mmd->afi.chunks_total;
if (backwards)
- promille -= 1000 * i / mmd->seconds_total;
+ promille -= 1000 * i / mmd->afi.seconds_total;
else
- promille += 1000 * i / mmd->seconds_total;
+ promille += 1000 * i / mmd->afi.seconds_total;
if (promille < 0)
promille = 0;
if (promille > 1000) {
mmd->new_vss_status_flags |= VSS_NEXT;
goto out;
}
- mmd->repos_request = (mmd->chunks_total * promille) / 1000;
+ mmd->repos_request = (mmd->afi.chunks_total * promille) / 1000;
mmd->new_vss_status_flags |= VSS_REPOS;
mmd->new_vss_status_flags &= ~VSS_NEXT;
mmd->events++;
}
/* jmp */
-int com_jmp(__a_unused int socket_fd, int argc, char **argv)
+int com_jmp(__a_unused int fd, int argc, char **argv)
{
long unsigned int i;
int ret;
return -E_COMMAND_SYNTAX;
mmd_lock();
ret = -E_NO_AUDIO_FILE;
- if (!mmd->chunks_total)
+ if (!mmd->afi.chunks_total)
goto out;
if (i > 100)
i = 100;
PARA_INFO_LOG("jumping to %lu%%\n", i);
- mmd->repos_request = (mmd->chunks_total * i + 50)/ 100;
+ mmd->repos_request = (mmd->afi.chunks_total * i + 50)/ 100;
PARA_INFO_LOG("sent: %lu, offset before jmp: %lu\n",
mmd->chunks_sent, mmd->offset);
mmd->new_vss_status_flags |= VSS_REPOS;
return get_cmd_ptr(buf, NULL);
}
-long int para_rand(long unsigned max)
+static long int para_rand(long unsigned max)
{
return (long int) ((max + 0.0) * (random() / (RAND_MAX + 1.0)));
}
RC4(&rc4_send_key, len, indata, outdata);
}
+static int read_command(int fd, char **result)
+{
+ int ret;
+ char buf[4096];
+ char *command = NULL;
+
+ for (;;) {
+ size_t numbytes;
+ char *p;
+
+ ret = recv_buffer(fd, buf, sizeof(buf));
+ if (ret < 0)
+ goto out;
+ if (!ret)
+ break;
+ numbytes = ret;
+ ret = -E_COMMAND_SYNTAX;
+ if (command && numbytes + strlen(command) > MAX_COMMAND_LEN) /* DOS */
+ goto out;
+ command = para_strcat(command, buf);
+ p = strstr(command, EOC_MSG);
+ if (p) {
+ *p = '\0';
+ break;
+ }
+ }
+ ret = command? 1 : -E_COMMAND_SYNTAX;
+out:
+ if (ret < 0)
+ free(command);
+ else
+ *result = command;
+ return ret;
+
+}
+
+/**
+ * perform user authentication and execute a command
+ *
+ * \param fd the file descriptor to send output to
+ * \param addr socket address info of peer
+ *
+ * \return EXIT_SUCCESS or EXIT_FAILURE
+ *
+ * Whenever para_server accepts an incoming tcp connection on
+ * the port it listens on, it forks and the resulting child
+ * calls this function.
+ *
+ * An RSA-based challenge/response is used to authenticate
+ * the peer. It that authentication succeeds, a random RC4
+ * session key is generated and sent back to the peer,
+ * encrypted with its RSA public key. From this point on,
+ * all transfers are crypted with this session key.
+ *
+ * Next it is checked if the peer supplied a valid server
+ * command or a command for the audio file selector currently
+ * in use. If yes, and if the user has sufficient
+ * permissions to execute that command, the function calls
+ * the corresponding command handler which does argument
+ * checking and further processing.
+ *
+ * In order to cope with a DOS attacks, a timeout is set up
+ * which terminates the function if the connection was not
+ * authenticated when the timeout expires.
+ *
+ * \sa alarm(2), rc4(3), crypt.c, crypt.h
+ */
int handle_connect(int fd, struct sockaddr_in *addr)
{
- int numbytes, ret, argc, use_rc4 = 0;
- char buf[STRINGSIZE];
+ int ret, argc, use_rc4 = 0;
+ char buf[4096];
unsigned char crypt_buf[MAXLINE];
- struct user u;
+ struct user *u;
struct server_command *cmd = NULL;
long unsigned challenge_nr, chall_response;
char **argv = NULL;
char *p, *command = NULL;
+ size_t numbytes;
signal(SIGCHLD, SIG_IGN);
signal(SIGINT, SIG_DFL);
signal(SIGHUP, SIG_DFL);
signal(SIGUSR1, SIG_IGN);
- in_addr = addr;
challenge_nr = random();
/* send Welcome message */
ret = send_va_buffer(fd, "This is para_server, version "
goto err_out;
if (numbytes < 9 || strncmp(buf, "auth rc4 ", 9))
- u.name = para_strdup(buf + 5); /* client version < 0.2.6 */
+ p = buf + 5; /* client version < 0.2.6 */
else {
- u.name = para_strdup(buf + 9); /* client version >= 0.2.6 */
+ 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", u.name);
- if ((ret = lookup_user(&u)) < 0)
+ use_rc4? "rc4" : "auth", p);
+ ret = -E_BAD_USER;
+ u = lookup_user(p);
+ if (!u)
goto err_out;
- ret = para_encrypt_challenge(u.rsa, challenge_nr, crypt_buf);
+ ret = para_encrypt_challenge(u->rsa, challenge_nr, crypt_buf);
if (ret <= 0)
goto err_out;
numbytes = ret;
- PARA_DEBUG_LOG("sending %d byte challenge\n", numbytes);
+ 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 (ret < 0)
goto err_out;
/* recv decrypted number */
- numbytes = recv_buffer(fd, buf, sizeof(buf));
- ret = numbytes;
+ ret = recv_buffer(fd, buf, sizeof(buf));
if (ret < 0)
goto err_out;
+ numbytes = ret;
ret = -E_AUTH;
if (!numbytes)
goto err_out;
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);
+ /* 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,
+ 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;
goto err_out;
if (use_rc4)
enable_crypt(fd, rc4_recv, rc4_send, NULL);
- /* read command */
- while ((numbytes = recv_buffer(fd, buf, sizeof(buf))) > 0) {
-// PARA_INFO_LOG("recvd: %s (%d)\n", buf, numbytes);
- ret = -E_COMMAND_SYNTAX;
- if (command && numbytes + strlen(command) > STRINGSIZE) /* DOS */
- goto err_out;
- command = para_strcat(command, buf);
- if ((p = strstr(command, EOC_MSG))) {
- *p = '\0';
- break;
- }
- }
- ret = numbytes;
+ ret = read_command(fd, &command);
if (ret < 0)
goto err_out;
ret = -E_BAD_CMD;
- /* parse command */
- if (!(cmd = parse_cmd(command)))
+ cmd = parse_cmd(command);
+ if (!cmd)
goto err_out;
/* valid command, check permissions */
- ret = check_perms(u.perms, cmd);
+ ret = check_perms(u->perms, cmd);
if (ret < 0)
goto err_out;
/* valid command and sufficient perms */
mmd_lock();
mmd->num_commands++;
mmd_unlock();
- PARA_NOTICE_LOG("calling com_%s() for %s@%s\n", cmd->name, u.name,
+ PARA_NOTICE_LOG("calling com_%s() for %s@%s\n", cmd->name, u->name,
inet_ntoa(addr->sin_addr));
ret = cmd->handler(fd, argc, argv);
if (ret >= 0) {
goto out;
}
err_out:
- if (ret != -E_SEND && ret != -E_RECV) {
- PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-ret));
+ PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-ret));
+ if (ret != -E_SEND && ret != -E_RECV)
send_va_buffer(fd, "%s\n", PARA_STRERROR(-ret));
- }
ret = EXIT_FAILURE;
out:
free(command);
free(argv);
mmd_lock();
- if (cmd && (cmd->perms & DB_WRITE) && ret >= 0)
+ if (cmd && (cmd->perms & AFS_WRITE) && ret >= 0)
mmd->events++;
mmd->active_connections--;
mmd_unlock();
projects / paraslash.git / blobdiff