X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=command.c;h=412769336a2896555142eac66cf6c9469f9c394b;hp=5790f11d278f95d4ad09964ab76af5d0ebf9e772;hb=823a4ff87a03ff9e1d2bfe8bc501f55ee4213649;hpb=fa9e0ecb219000e07eaf694f50679a8edfb5dc9e diff --git a/command.c b/command.c index 5790f11d..41276933 100644 --- a/command.c +++ b/command.c @@ -1,16 +1,20 @@ /* - * Copyright (C) 1997-2012 Andre Noll + * Copyright (C) 1997-2014 Andre Noll * * Licensed under the GPL v2. For licencing details see COPYING. */ /** \file command.c Client authentication and server commands. */ +#include +#include #include #include -#include #include #include +#include +#include +#include #include "para.h" #include "error.h" @@ -36,6 +40,9 @@ #include "signal.h" #include "version.h" +static struct server_command afs_cmds[] = {DEFINE_AFS_CMD_ARRAY}; +static struct server_command server_cmds[] = {DEFINE_SERVER_CMD_ARRAY}; + /** Commands including options must be shorter than this. */ #define MAX_COMMAND_LEN 32768 @@ -102,12 +109,12 @@ static char *vss_get_status_flags(unsigned int flags) return msg; } -static char *get_status(struct misc_meta_data *nmmd, int parser_friendly) +static unsigned get_status(struct misc_meta_data *nmmd, int parser_friendly, + char **result) { char mtime[30] = ""; char *status, *flags; /* vss status info */ /* nobody updates our version of "now" */ - char *ut = get_server_uptime_str(NULL); long offset = (nmmd->offset + 500) / 1000; struct timeval current_time; struct tm mtime_tm; @@ -120,7 +127,7 @@ static char *get_status(struct misc_meta_data *nmmd, int parser_friendly) localtime_r(&nmmd->mtime, &mtime_tm); strftime(mtime, 29, "%b %d %Y", &mtime_tm); } - gettimeofday(¤t_time, NULL); + clock_get_realtime(¤t_time); /* * The calls to WRITE_STATUS_ITEM() below never fail because * b->max_size is zero (unlimited), see para_printf(). However, clang @@ -141,8 +148,8 @@ static char *get_status(struct misc_meta_data *nmmd, int parser_friendly) (long unsigned)current_time.tv_usec); free(flags); free(status); - free(ut); - return b.buf; + *result = b.buf; + return b.offset; } static int check_sender_args(int argc, char * const * argv, struct sender_command_data *scd) @@ -216,8 +223,8 @@ int send_sb(struct stream_cipher_context *scc, void *buf, size_t numbytes, int ret; struct sb_context *sbc; struct iovec iov[2]; - struct sb_buffer sbb = SBB_INIT(band, buf, numbytes); sb_transformation trafo = band < SBD_PROCEED? NULL : sc_trafo; + struct sb_buffer sbb = SBB_INIT(band, buf, numbytes); sbc = sb_new_send(&sbb, dont_free, trafo, scc->send); do { @@ -254,6 +261,19 @@ __printf_3_4 int send_sb_va(struct stream_cipher_context *scc, int band, return send_sb(scc, msg, ret, band, false); } +/** + * Send an error message to a client. + * + * \param cc Client info. + * \param err The (positive) error code. + * + * \return The return value of the underlying call to send_sb_va(). + */ +int send_strerror(struct command_context *cc, int err) +{ + return send_sb_va(&cc->scc, SBD_ERROR_LOG, "%s\n", para_strerror(err)); +} + /** * Send a sideband packet through a blocking file descriptor. * @@ -304,31 +324,28 @@ fail: return ret; } -int com_sender(struct command_context *cc) +static int com_sender(struct command_context *cc) { - int i, ret; + int i, ret = 0; char *msg = NULL; struct sender_command_data scd; if (cc->argc < 2) { for (i = 0; senders[i].name; i++) { - char *tmp = make_message("%s%s\n", - msg? msg : "", senders[i].name); + char *tmp; + ret = xasprintf(&tmp, "%s%s\n", msg? msg : "", + senders[i].name); free(msg); msg = tmp; } - ret = sc_send_buffer(&cc->scc, msg); - free(msg); - return ret; + return send_sb(&cc->scc, msg, ret, SBD_OUTPUT, false); } ret = check_sender_args(cc->argc, cc->argv, &scd); if (ret < 0) { if (scd.sender_num < 0) return ret; msg = senders[scd.sender_num].help(); - ret = sc_send_buffer(&cc->scc, msg); - free(msg); - return ret; + return send_sb(&cc->scc, msg, strlen(msg), SBD_OUTPUT, false); } switch (scd.cmd_num) { @@ -355,11 +372,10 @@ int com_sender(struct command_context *cc) } /* server info */ -int com_si(struct command_context *cc) +static int com_si(struct command_context *cc) { int i, ret; - char *ut; - char *sender_info = NULL; + char *msg, *ut, *sender_info = NULL; if (cc->argc != 1) return -E_COMMAND_SYNTAX; @@ -369,8 +385,9 @@ int com_si(struct command_context *cc) sender_info = para_strcat(sender_info, info); free(info); } - ut = get_server_uptime_str(now); - ret = sc_send_va_buffer(&cc->scc, "version: " GIT_VERSION "\n" + ut = daemon_get_uptime_str(now); + ret = xasprintf(&msg, + "version: %s\n" "up: %s\nplayed: %u\n" "server_pid: %d\n" "afs_pid: %d\n" @@ -378,6 +395,7 @@ int com_si(struct command_context *cc) "current loglevel: %s\n" "supported audio formats: %s\n" "%s", + version_git(), ut, mmd->num_played, (int)getppid(), (int)mmd->afs_pid, @@ -385,24 +403,25 @@ int com_si(struct command_context *cc) mmd->num_commands, mmd->num_connects, conf.loglevel_arg, - SERVER_AUDIO_FORMATS, + AUDIO_FORMAT_HANDLERS, sender_info ); mutex_unlock(mmd_mutex); free(ut); free(sender_info); - return ret; + return send_sb(&cc->scc, msg, ret, SBD_OUTPUT, false); } /* version */ -int com_version(struct command_context *cc) +static int com_version(struct command_context *cc) { + char *msg; + size_t len; + if (cc->argc != 1) return -E_COMMAND_SYNTAX; - return sc_send_buffer(&cc->scc, VERSION_TEXT("server") - "built: " BUILD_DATE "\n" - UNAME_RS ", " CC_VERSION "\n" - ); + len = xasprintf(&msg, "%s", version_text("server")); + return send_sb(&cc->scc, msg, len, SBD_OUTPUT, false); } #define EMPTY_STATUS_ITEMS \ @@ -438,10 +457,13 @@ int com_version(struct command_context *cc) * * This is used by vss when currently no audio file is open. */ -static char *empty_status_items(int parser_friendly) +static unsigned empty_status_items(int parser_friendly, char **result) { + char *esi; + unsigned len; + if (parser_friendly) - return make_message( + len = xasprintf(&esi, #define ITEM(x) "0004 %02x:\n" EMPTY_STATUS_ITEMS #undef ITEM @@ -449,19 +471,22 @@ static char *empty_status_items(int parser_friendly) EMPTY_STATUS_ITEMS #undef ITEM ); - return make_message( - #define ITEM(x) "%s:\n" - EMPTY_STATUS_ITEMS - #undef ITEM - #define ITEM(x) ,status_item_list[SI_ ## x] - EMPTY_STATUS_ITEMS - #undef ITEM - ); + else + len = xasprintf(&esi, + #define ITEM(x) "%s:\n" + EMPTY_STATUS_ITEMS + #undef ITEM + #define ITEM(x) ,status_item_list[SI_ ## x] + EMPTY_STATUS_ITEMS + #undef ITEM + ); + *result = esi; + return len; } #undef EMPTY_STATUS_ITEMS /* stat */ -int com_stat(struct command_context *cc) +static int com_stat(struct command_context *cc) { int i, ret; struct misc_meta_data tmp, *nmmd = &tmp; @@ -495,16 +520,14 @@ int com_stat(struct command_context *cc) return -E_COMMAND_SYNTAX; for (;;) { mmd_dup(nmmd); - s = get_status(nmmd, parser_friendly); - ret = sc_send_buffer(&cc->scc, s); - free(s); + ret = get_status(nmmd, parser_friendly, &s); + ret = send_sb(&cc->scc, s, ret, SBD_OUTPUT, false); if (ret < 0) goto out; if (nmmd->vss_status_flags & VSS_NEXT) { - static char *esi; - if (!esi) - esi = empty_status_items(parser_friendly); - ret = sc_send_buffer(&cc->scc, esi); + char *esi; + ret = empty_status_items(parser_friendly, &esi); + ret = send_sb(&cc->scc, esi, ret, SBD_OUTPUT, false); if (ret < 0) goto out; } else @@ -513,29 +536,29 @@ int com_stat(struct command_context *cc) if (num > 0 && !--num) goto out; sleep(50); + ret = -E_SERVER_CRASH; if (getppid() == 1) - return -E_SERVER_CRASH; + goto out; } out: return ret; } -static int send_list_of_commands(struct stream_cipher_context *scc, struct server_command *cmd, +static int send_list_of_commands(struct command_context *cc, struct server_command *cmd, const char *handler) { - int ret, i; + char *msg = NULL; - for (i = 1; cmd->name; cmd++, i++) { - char *perms = cmd_perms_itohuman(cmd->perms); - ret = sc_send_va_buffer(scc, "%s\t%s\t%s\t%s\n", cmd->name, - handler, - perms, - cmd->description); + for (; cmd->name; cmd++) { + char *tmp, *perms = cmd_perms_itohuman(cmd->perms); + tmp = make_message("%s\t%s\t%s\t%s\n", cmd->name, handler, + perms, cmd->description); free(perms); - if (ret < 0) - return ret; + msg = para_strcat(msg, tmp); + free(tmp); } - return 1; + assert(msg); + return send_sb(&cc->scc, msg, strlen(msg), SBD_OUTPUT, false); } /* returns string that must be freed by the caller */ @@ -560,25 +583,24 @@ static struct server_command *get_cmd_ptr(const char *name, char **handler) } /* help */ -int com_help(struct command_context *cc) +static int com_help(struct command_context *cc) { struct server_command *cmd; - char *perms, *handler; + char *perms, *handler, *buf; int ret; if (cc->argc < 2) { /* no argument given, print list of commands */ - if ((ret = send_list_of_commands(&cc->scc, server_cmds, "server")) < 0) + if ((ret = send_list_of_commands(cc, server_cmds, "server")) < 0) return ret; - return send_list_of_commands(&cc->scc, afs_cmds, "afs"); + return send_list_of_commands(cc, afs_cmds, "afs"); } /* argument given for help */ cmd = get_cmd_ptr(cc->argv[1], &handler); if (!cmd) return -E_BAD_CMD; perms = cmd_perms_itohuman(cmd->perms); - ret = sc_send_va_buffer(&cc->scc, - "%s - %s\n\n" + ret = xasprintf(&buf, "%s - %s\n\n" "handler: %s\n" "permissions: %s\n" "usage: %s\n\n" @@ -592,11 +614,11 @@ int com_help(struct command_context *cc) ); free(perms); free(handler); - return ret; + return send_sb(&cc->scc, buf, ret, SBD_OUTPUT, false); } /* hup */ -int com_hup(struct command_context *cc) +static int com_hup(struct command_context *cc) { if (cc->argc != 1) return -E_COMMAND_SYNTAX; @@ -605,7 +627,7 @@ int com_hup(struct command_context *cc) } /* term */ -int com_term(struct command_context *cc) +static int com_term(struct command_context *cc) { if (cc->argc != 1) return -E_COMMAND_SYNTAX; @@ -613,7 +635,7 @@ int com_term(struct command_context *cc) return 1; } -int com_play(struct command_context *cc) +static int com_play(struct command_context *cc) { if (cc->argc != 1) return -E_COMMAND_SYNTAX; @@ -625,7 +647,7 @@ int com_play(struct command_context *cc) } /* stop */ -int com_stop(struct command_context *cc) +static int com_stop(struct command_context *cc) { if (cc->argc != 1) return -E_COMMAND_SYNTAX; @@ -638,7 +660,7 @@ int com_stop(struct command_context *cc) } /* pause */ -int com_pause(struct command_context *cc) +static int com_pause(struct command_context *cc) { if (cc->argc != 1) return -E_COMMAND_SYNTAX; @@ -653,7 +675,7 @@ int com_pause(struct command_context *cc) } /* next */ -int com_next(struct command_context *cc) +static int com_next(struct command_context *cc) { if (cc->argc != 1) return -E_COMMAND_SYNTAX; @@ -665,7 +687,7 @@ int com_next(struct command_context *cc) } /* nomore */ -int com_nomore(struct command_context *cc) +static int com_nomore(struct command_context *cc) { if (cc->argc != 1) return -E_COMMAND_SYNTAX; @@ -677,7 +699,7 @@ int com_nomore(struct command_context *cc) } /* ff */ -int com_ff(struct command_context *cc) +static int com_ff(struct command_context *cc) { long promille; int ret, backwards = 0; @@ -716,7 +738,7 @@ out: } /* jmp */ -int com_jmp(struct command_context *cc) +static int com_jmp(struct command_context *cc) { long unsigned int i; int ret; @@ -754,58 +776,6 @@ static int check_perms(unsigned int perms, struct server_command *cmd_ptr) return (cmd_ptr->perms & perms) < cmd_ptr->perms ? -E_PERM : 0; } -/* - * Parse first string from *cmd and lookup in table of valid commands. - * On error, NULL is returned. - */ -static struct server_command *parse_cmd(const char *cmdstr) -{ - char buf[255]; - int n = 0; - - sscanf(cmdstr, "%200s%n", buf, &n); - if (!n) - return NULL; - buf[n] = '\0'; - return get_cmd_ptr(buf, NULL); -} - -static int read_command(struct stream_cipher_context *scc, char **result) -{ - int ret; - char buf[4096]; - char *command = NULL; - - for (;;) { - size_t numbytes; - char *p; - - ret = sc_recv_buffer(scc, 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; - -} - static void reset_signals(void) { para_sigaction(SIGCHLD, SIG_IGN); @@ -814,15 +784,20 @@ static void reset_signals(void) para_sigaction(SIGHUP, SIG_DFL); } +struct connection_features { + bool sideband_requested; + bool aes_ctr128_requested; +}; + static int parse_auth_request(char *buf, int len, struct user **u, - bool *use_sideband) + struct connection_features *cf) { int ret; char *p, *username, **features = NULL; size_t auth_rq_len = strlen(AUTH_REQUEST_MSG); *u = NULL; - *use_sideband = false; + memset(cf, 0, sizeof(*cf)); if (len < auth_rq_len + 2) return -E_AUTH_REQUEST; if (strncmp(buf, AUTH_REQUEST_MSG, auth_rq_len) != 0) @@ -838,15 +813,16 @@ static int parse_auth_request(char *buf, int len, struct user **u, create_argv(p, ",", &features); for (i = 0; features[i]; i++) { if (strcmp(features[i], "sideband") == 0) - *use_sideband = true; + cf->sideband_requested = true; + else if (strcmp(features[i], "aes_ctr128") == 0) + cf->aes_ctr128_requested = true; else { ret = -E_BAD_FEATURE; goto out; } } } - PARA_DEBUG_LOG("received auth request for user %s (sideband = %s)\n", - username, *use_sideband? "true" : "false"); + PARA_DEBUG_LOG("received auth request for user %s\n", username); *u = lookup_user(username); ret = 1; out: @@ -856,6 +832,38 @@ out: #define HANDSHAKE_BUFSIZE 4096 +static int parse_sb_command(struct command_context *cc, struct iovec *iov) +{ + int ret, i; + char *p, *end; + + ret = -E_BAD_CMD; + if (iov->iov_base == NULL || iov->iov_len == 0) + goto out; + p = iov->iov_base; + p[iov->iov_len - 1] = '\0'; /* just to be sure */ + cc->cmd = get_cmd_ptr(p, NULL); + if (!cc->cmd) + goto out; + ret = check_perms(cc->u->perms, cc->cmd); + if (ret < 0) + goto out; + end = iov->iov_base + iov->iov_len; + for (i = 0; p < end; i++) + p += strlen(p) + 1; + cc->argc = i; + cc->argv = para_malloc((cc->argc + 1) * sizeof(char *)); + for (i = 0, p = iov->iov_base; p < end; i++) { + cc->argv[i] = para_strdup(p); + p += strlen(p) + 1; + } + cc->argv[cc->argc] = NULL; + ret = cc->argc; +out: + free(iov->iov_base); + return ret; +} + /** * Perform user authentication and execute a command. * @@ -888,9 +896,11 @@ __noreturn void handle_connect(int fd, const char *peername) int ret; unsigned char rand_buf[CHALLENGE_SIZE + 2 * SESSION_KEY_LEN]; unsigned char challenge_hash[HASH_SIZE]; - char *p, *command = NULL, *buf = para_malloc(HANDSHAKE_BUFSIZE) /* must be on the heap */; + char *command = NULL, *buf = para_malloc(HANDSHAKE_BUFSIZE) /* must be on the heap */; size_t numbytes; struct command_context cc_struct = {.peer = peername}, *cc = &cc_struct; + struct iovec iov; + struct connection_features cf; cc->scc.fd = fd; reset_signals(); @@ -901,7 +911,7 @@ __noreturn void handle_connect(int fd, const char *peername) /* send Welcome message */ ret = write_va_buffer(fd, "This is para_server, version " PACKAGE_VERSION ".\n" - "Features: sideband,foo\n" + "Features: sideband,aes_ctr128\n" ); if (ret < 0) goto net_err; @@ -909,12 +919,14 @@ __noreturn void handle_connect(int fd, const char *peername) ret = recv_buffer(fd, buf, HANDSHAKE_BUFSIZE); if (ret < 0) goto net_err; - ret = parse_auth_request(buf, ret, &cc->u, &cc->use_sideband); + ret = parse_auth_request(buf, ret, &cc->u, &cf); if (ret < 0) goto net_err; - p = buf + strlen(AUTH_REQUEST_MSG); - PARA_DEBUG_LOG("received auth request for user %s\n", p); - cc->u = lookup_user(p); + if (!cf.sideband_requested) { /* sideband is mandatory */ + PARA_ERROR_LOG("client did not request sideband\n"); + ret = -E_BAD_FEATURE; + goto net_err; + } if (cc->u) { get_random_bytes_or_die(rand_buf, sizeof(rand_buf)); ret = pub_encrypt(cc->u->pubkey, rand_buf, sizeof(rand_buf), @@ -931,25 +943,19 @@ __noreturn void handle_connect(int fd, const char *peername) numbytes = 256; get_random_bytes_or_die((unsigned char *)buf, numbytes); } - PARA_DEBUG_LOG("sending %u byte challenge + rc4 keys (%zu bytes)\n", + PARA_DEBUG_LOG("sending %u byte challenge + session key (%zu bytes)\n", CHALLENGE_SIZE, numbytes); - if (cc->use_sideband) { - ret = send_sb(&cc->scc, buf, numbytes, SBD_CHALLENGE, false); - buf = NULL; - if (ret < 0) - goto net_err; - buf = para_malloc(HANDSHAKE_BUFSIZE); - } else { - ret = write_all(fd, buf, numbytes); - if (ret < 0) - goto net_err; - } - /* recv challenge response */ - ret = recv_bin_buffer(fd, buf, HASH_SIZE); + ret = send_sb(&cc->scc, buf, numbytes, SBD_CHALLENGE, false); + buf = NULL; if (ret < 0) goto net_err; - numbytes = ret; - PARA_DEBUG_LOG("received %d bytes challenge response\n", ret); + ret = recv_sb(&cc->scc, SBD_CHALLENGE_RESPONSE, + HANDSHAKE_BUFSIZE, &iov); + if (ret < 0) + goto net_err; + buf = iov.iov_base; + numbytes = iov.iov_len; + PARA_DEBUG_LOG("received %zu bytes challenge response\n", numbytes); ret = -E_BAD_USER; if (!cc->u) goto net_err; @@ -967,26 +973,17 @@ __noreturn void handle_connect(int fd, const char *peername) alarm(0); PARA_INFO_LOG("good auth for %s\n", cc->u->name); /* init stream cipher keys with the second part of the random buffer */ - cc->scc.recv = sc_new(rand_buf + CHALLENGE_SIZE, SESSION_KEY_LEN); - cc->scc.send = sc_new(rand_buf + CHALLENGE_SIZE + SESSION_KEY_LEN, SESSION_KEY_LEN); - ret = sc_send_buffer(&cc->scc, PROCEED_MSG); + cc->scc.recv = sc_new(rand_buf + CHALLENGE_SIZE, SESSION_KEY_LEN, + cf.aes_ctr128_requested); + cc->scc.send = sc_new(rand_buf + CHALLENGE_SIZE + SESSION_KEY_LEN, + SESSION_KEY_LEN, cf.aes_ctr128_requested); + ret = send_sb(&cc->scc, NULL, 0, SBD_PROCEED, false); if (ret < 0) goto net_err; - ret = read_command(&cc->scc, &command); - if (ret == -E_COMMAND_SYNTAX) - goto err_out; + ret = recv_sb(&cc->scc, SBD_COMMAND, MAX_COMMAND_LEN, &iov); if (ret < 0) goto net_err; - ret = -E_BAD_CMD; - cc->cmd = parse_cmd(command); - if (!cc->cmd) - goto err_out; - /* valid command, check permissions */ - ret = check_perms(cc->u->perms, cc->cmd); - if (ret < 0) - goto err_out; - /* valid command and sufficient perms */ - ret = create_argv(command, "\n", &cc->argv); + ret = parse_sb_command(cc, &iov); if (ret < 0) goto err_out; cc->argc = ret; @@ -1000,18 +997,24 @@ __noreturn void handle_connect(int fd, const char *peername) if (ret >= 0) goto out; err_out: - sc_send_va_buffer(&cc->scc, "%s\n", para_strerror(-ret)); + if (send_strerror(cc, -ret) >= 0) + send_sb(&cc->scc, NULL, 0, SBD_EXIT__FAILURE, true); net_err: PARA_NOTICE_LOG("%s\n", para_strerror(-ret)); out: free(buf); free(command); - sc_free(cc->scc.recv); - sc_free(cc->scc.send); mutex_lock(mmd_mutex); if (cc->cmd && (cc->cmd->perms & AFS_WRITE) && ret >= 0) mmd->events++; mmd->active_connections--; mutex_unlock(mmd_mutex); + if (ret >= 0) { + ret = send_sb(&cc->scc, NULL, 0, SBD_EXIT__SUCCESS, true); + if (ret < 0) + PARA_NOTICE_LOG("%s\n", para_strerror(-ret)); + } + sc_free(cc->scc.recv); + sc_free(cc->scc.send); exit(ret < 0? EXIT_FAILURE : EXIT_SUCCESS); }