X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=command.c;h=6777ccc971e2590bd2d46879ba428ff1f327f7d8;hp=585bb31c54b8df7395c8330f7f4d6e7b15890ad8;hb=884f36e554f9c58815bc24cc3f1f033ab30cb7c7;hpb=435ad905b15bdad01dc3189bed5bf1d647ed1229 diff --git a/command.c b/command.c index 585bb31c..6777ccc9 100644 --- a/command.c +++ b/command.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 1997-2014 Andre Noll + * Copyright (C) 1997 Andre Noll * * Licensed under the GPL v2. For licencing details see COPYING. */ @@ -35,11 +35,31 @@ #include "fd.h" #include "ipc.h" #include "user_list.h" -#include "server_command_list.h" -#include "afs_command_list.h" +#include "server.command_list.h" +#include "afs.command_list.h" #include "signal.h" #include "version.h" +typedef int server_command_handler_t(struct command_context *); +static server_command_handler_t SERVER_COMMAND_HANDLERS; +server_command_handler_t AFS_COMMAND_HANDLERS; + +/* Defines one command of para_server. */ +struct server_command { + /* The name of the command. */ + const char *name; + /* Pointer to the function that handles the command. */ + server_command_handler_t *handler; + /* The privileges a user must have to execute this command. */ + unsigned int perms; + /* One-line description of the command. */ + const char *description; + /* Summary of the command line options. */ + const char *usage; + /* The long help text. */ + const char *help; +}; + static struct server_command afs_cmds[] = {DEFINE_AFS_CMD_ARRAY}; static struct server_command server_cmds[] = {DEFINE_SERVER_CMD_ARRAY}; @@ -55,20 +75,14 @@ static void dummy(__a_unused int s) { } -static void mmd_dup(struct misc_meta_data *new_mmd) -{ - mutex_lock(mmd_mutex); - *new_mmd = *mmd; - mutex_unlock(mmd_mutex); -} - /* - * Compute human readable string containing vss status for given integer value. + * Compute human readable vss status text. * - * We don't want to use vss_playing() and friends here because we take a - * snapshot of the mmd struct and use the copy for computing the state of the - * vss. If the real data were used, we would take the mmd lock for a rather - * long time or risk to get an inconsistent view. + * We can't call vss_playing() and friends here because those functions read + * the flags from the primary mmd structure, so calling them from command + * handler context would require to take the mmd lock. At the time the function + * is called we already took a copy of the mmd structure and want to use the + * flags value of the copy for computing the vss status text. */ static char *vss_status_tohuman(unsigned int flags) { @@ -112,21 +126,15 @@ static char *vss_get_status_flags(unsigned int flags) 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" */ 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); flags = vss_get_status_flags(nmmd->vss_status_flags); - if (nmmd->size) { /* parent currently has an audio file open */ - localtime_r(&nmmd->mtime, &mtime_tm); - strftime(mtime, 29, "%b %d %Y", &mtime_tm); - } clock_get_realtime(¤t_time); /* * The calls to WRITE_STATUS_ITEM() below never fail because @@ -134,8 +142,6 @@ static unsigned get_status(struct misc_meta_data *nmmd, int parser_friendly, * is not smart enough to prove this and complains nevertheless. * Casting the return value to void silences clang. */ - (void)WRITE_STATUS_ITEM(&b, SI_FILE_SIZE, "%zu\n", nmmd->size / 1024); - (void)WRITE_STATUS_ITEM(&b, SI_MTIME, "%s\n", mtime); (void)WRITE_STATUS_ITEM(&b, SI_STATUS, "%s\n", status); (void)WRITE_STATUS_ITEM(&b, SI_STATUS_FLAGS, "%s\n", flags); (void)WRITE_STATUS_ITEM(&b, SI_OFFSET, "%li\n", offset); @@ -155,11 +161,10 @@ static unsigned get_status(struct misc_meta_data *nmmd, int parser_friendly, static int check_sender_args(int argc, char * const * argv, struct sender_command_data *scd) { int i; - /* this has to match sender.h */ - const char *subcmds[] = {"add", "delete", "allow", "deny", "on", "off", NULL}; + const char *subcmds[] = {SENDER_SUBCOMMANDS NULL}; scd->sender_num = -1; - if (argc < 2) + if (argc < 3) return -E_COMMAND_SYNTAX; for (i = 0; senders[i].name; i++) if (!strcmp(senders[i].name, argv[1])) @@ -177,19 +182,19 @@ static int check_sender_args(int argc, char * const * argv, struct sender_comman if (!senders[scd->sender_num].client_cmds[scd->cmd_num]) return -E_SENDER_CMD; switch (scd->cmd_num) { - case SENDER_ON: - case SENDER_OFF: + case SENDER_on: + case SENDER_off: if (argc != 3) return -E_COMMAND_SYNTAX; break; - case SENDER_DENY: - case SENDER_ALLOW: + case SENDER_deny: + case SENDER_allow: if (argc != 4 || parse_cidr(argv[3], scd->host, sizeof(scd->host), &scd->netmask) == NULL) return -E_COMMAND_SYNTAX; break; - case SENDER_ADD: - case SENDER_DELETE: + case SENDER_add: + case SENDER_delete: if (argc != 4) return -E_COMMAND_SYNTAX; return parse_fec_url(argv[3], scd); @@ -210,7 +215,7 @@ static int check_sender_args(int argc, char * const * argv, struct sender_comman * * The nonblock flag must be disabled for the file descriptor given by \a scc. * - * Stream cipher encryption is automatically activated if neccessary via the + * Stream cipher encryption is automatically activated if necessary via the * sideband transformation, depending on the value of \a band. * * \return Standard. @@ -352,8 +357,8 @@ static int com_sender(struct command_context *cc) } switch (scd.cmd_num) { - case SENDER_ADD: - case SENDER_DELETE: + case SENDER_add: + case SENDER_delete: assert(senders[scd.sender_num].resolve_target); ret = senders[scd.sender_num].resolve_target(cc->argv[3], &scd); if (ret < 0) @@ -363,8 +368,10 @@ static int com_sender(struct command_context *cc) for (i = 0; i < 10; i++) { mutex_lock(mmd_mutex); if (mmd->sender_cmd_data.cmd_num >= 0) { + /* another sender command is active, retry in 100ms */ + struct timespec ts = {.tv_nsec = 100 * 1000 * 1000}; mutex_unlock(mmd_mutex); - usleep(100 * 1000); + nanosleep(&ts, NULL); continue; } mmd->sender_cmd_data = scd; @@ -383,7 +390,7 @@ static int com_si(struct command_context *cc) if (cc->argc != 1) return -E_COMMAND_SYNTAX; mutex_lock(mmd_mutex); - ut = get_server_uptime_str(now); + ut = daemon_get_uptime_str(now); ret = xasprintf(&msg, "up: %s\nplayed: %u\n" "server_pid: %d\n" @@ -411,12 +418,14 @@ static int com_version(struct command_context *cc) char *msg; size_t len; - if (cc->argc != 1) - return -E_COMMAND_SYNTAX; - len = xasprintf(&msg, "%s", version_text("server")); + if (cc->argc > 1 && strcmp(cc->argv[1], "-v") == 0) + len = xasprintf(&msg, "%s", version_text("server")); + else + len = xasprintf(&msg, "%s\n", version_single_line("server")); return send_sb(&cc->scc, msg, len, SBD_OUTPUT, false); } +/** These status items are cleared if no audio file is currently open. */ #define EMPTY_STATUS_ITEMS \ ITEM(PATH) \ ITEM(DIRECTORY) \ @@ -443,7 +452,11 @@ static int com_version(struct command_context *cc) ITEM(YEAR) \ ITEM(ALBUM) \ ITEM(COMMENT) \ - ITEM(AMPLIFICATION) + ITEM(MTIME) \ + ITEM(FILE_SIZE) \ + ITEM(CHUNK_TIME) \ + ITEM(NUM_CHUNKS) \ + ITEM(AMPLIFICATION) \ /** * Write a list of audio-file related status items with empty values. @@ -460,7 +473,7 @@ static unsigned empty_status_items(int parser_friendly, char **result) #define ITEM(x) "0004 %02x:\n" EMPTY_STATUS_ITEMS #undef ITEM - #define ITEM(x) , SI_ ## x + #define ITEM(x) , (unsigned) SI_ ## x EMPTY_STATUS_ITEMS #undef ITEM ); @@ -512,7 +525,13 @@ static int com_stat(struct command_context *cc) if (i != cc->argc) return -E_COMMAND_SYNTAX; for (;;) { - mmd_dup(nmmd); + /* + * Copy the mmd structure to minimize the time we hold the mmd + * lock. + */ + mutex_lock(mmd_mutex); + *nmmd = *mmd; + mutex_unlock(mmd_mutex); ret = get_status(nmmd, parser_friendly, &s); ret = send_sb(&cc->scc, s, ret, SBD_OUTPUT, false); if (ret < 0) @@ -709,6 +728,7 @@ static int com_ff(struct command_context *cc) ret = -E_NO_AUDIO_FILE; if (!mmd->afd.afhi.chunks_total || !mmd->afd.afhi.seconds_total) goto out; + ret = 1; promille = (1000 * mmd->current_chunk) / mmd->afd.afhi.chunks_total; if (backwards) promille -= 1000 * i / mmd->afd.afhi.seconds_total; @@ -716,7 +736,7 @@ static int com_ff(struct command_context *cc) promille += 1000 * i / mmd->afd.afhi.seconds_total; if (promille < 0) promille = 0; - if (promille > 1000) { + if (promille > 1000) { mmd->new_vss_status_flags |= VSS_NEXT; goto out; } @@ -724,7 +744,6 @@ static int com_ff(struct command_context *cc) mmd->new_vss_status_flags |= VSS_REPOS; mmd->new_vss_status_flags &= ~VSS_NEXT; mmd->events++; - ret = 1; out: mutex_unlock(mmd_mutex); return ret; @@ -747,8 +766,8 @@ static int com_jmp(struct command_context *cc) if (i > 100) i = 100; PARA_INFO_LOG("jumping to %lu%%\n", i); - mmd->repos_request = (mmd->afd.afhi.chunks_total * i + 50)/ 100; - PARA_INFO_LOG("sent: %lu, offset before jmp: %lu\n", + mmd->repos_request = (mmd->afd.afhi.chunks_total * i + 50) / 100; + PARA_INFO_LOG("sent: %lu, offset before jmp: %li\n", mmd->chunks_sent, mmd->offset); mmd->new_vss_status_flags |= VSS_REPOS; mmd->new_vss_status_flags &= ~VSS_NEXT; @@ -759,11 +778,21 @@ out: return ret; } +static int com_tasks(struct command_context *cc) +{ + char *tl = server_get_tasks(); + int ret = 1; + + if (tl) + ret = send_sb(&cc->scc, tl, strlen(tl), SBD_OUTPUT, false); + return ret; +} + /* * check if perms are sufficient to exec a command having perms cmd_perms. * Returns 0 if perms are sufficient, -E_PERM otherwise. */ -static int check_perms(unsigned int perms, struct server_command *cmd_ptr) +static int check_perms(unsigned int perms, const struct server_command *cmd_ptr) { PARA_DEBUG_LOG("checking permissions\n"); return (cmd_ptr->perms & perms) < cmd_ptr->perms ? -E_PERM : 0; @@ -778,7 +807,6 @@ static void reset_signals(void) } struct connection_features { - bool sideband_requested; bool aes_ctr128_requested; }; @@ -806,8 +834,8 @@ 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) - cf->sideband_requested = true; - else if (strcmp(features[i], "aes_ctr128") == 0) + continue; + if (strcmp(features[i], "aes_ctr128") == 0) cf->aes_ctr128_requested = true; else { ret = -E_BAD_FEATURE; @@ -825,22 +853,23 @@ out: #define HANDSHAKE_BUFSIZE 4096 -static int parse_sb_command(struct command_context *cc, struct iovec *iov) +static int run_command(struct command_context *cc, struct iovec *iov, + const char *peername) { int ret, i; char *p, *end; + struct server_command *cmd; - ret = -E_BAD_CMD; if (iov->iov_base == NULL || iov->iov_len == 0) - goto out; + return -E_BAD_CMD; 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); + cmd = get_cmd_ptr(p, NULL); + if (!cmd) + return -E_BAD_CMD; + ret = check_perms(cc->u->perms, cmd); if (ret < 0) - goto out; + return ret; end = iov->iov_base + iov->iov_len; for (i = 0; p < end; i++) p += strlen(p) + 1; @@ -851,9 +880,15 @@ static int parse_sb_command(struct command_context *cc, struct iovec *iov) p += strlen(p) + 1; } cc->argv[cc->argc] = NULL; - ret = cc->argc; -out: - free(iov->iov_base); + PARA_NOTICE_LOG("calling com_%s() for %s@%s\n", cmd->name, + cc->u->name, peername); + ret = cmd->handler(cc); + free_argv(cc->argv); + mutex_lock(mmd_mutex); + mmd->num_commands++; + if (ret >= 0 && (cmd->perms & AFS_WRITE)) + mmd->events++; + mutex_unlock(mmd_mutex); return ret; } @@ -863,24 +898,22 @@ out: * \param fd The file descriptor to send output to. * \param peername Identifies the connecting peer. * - * Whenever para_server accepts an incoming tcp connection on - * the port it listens on, it forks and the resulting child - * calls this function. + * 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 - * 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. + * An RSA-based challenge/response is used to authenticate the peer. It that + * authentication succeeds, a random 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. If yes, and if the user has sufficient + * Next it is checked if the peer supplied a valid server command or a command + * for the audio file selector. 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. + * 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), crypt.c, crypt.h */ @@ -903,7 +936,7 @@ __noreturn void handle_connect(int fd, const char *peername) goto net_err; /* send Welcome message */ ret = write_va_buffer(fd, "This is para_server, version " - PACKAGE_VERSION ".\n" + PACKAGE_VERSION ".\n" "Features: sideband,aes_ctr128\n" ); if (ret < 0) @@ -915,11 +948,6 @@ __noreturn void handle_connect(int fd, const char *peername) ret = parse_auth_request(buf, ret, &cc->u, &cf); if (ret < 0) goto net_err; - 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), @@ -936,7 +964,7 @@ __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 + session key (%zu bytes)\n", + PARA_DEBUG_LOG("sending %d byte challenge + session key (%zu bytes)\n", CHALLENGE_SIZE, numbytes); ret = send_sb(&cc->scc, buf, numbytes, SBD_CHALLENGE, false); buf = NULL; @@ -976,17 +1004,10 @@ __noreturn void handle_connect(int fd, const char *peername) ret = recv_sb(&cc->scc, SBD_COMMAND, MAX_COMMAND_LEN, &iov); if (ret < 0) goto net_err; - ret = parse_sb_command(cc, &iov); + ret = run_command(cc, &iov, peername); + free(iov.iov_base); if (ret < 0) goto err_out; - cc->argc = ret; - PARA_NOTICE_LOG("calling com_%s() for %s@%s\n", cc->cmd->name, - cc->u->name, peername); - ret = cc->cmd->handler(cc); - free_argv(cc->argv); - mutex_lock(mmd_mutex); - mmd->num_commands++; - mutex_unlock(mmd_mutex); if (ret >= 0) goto out; err_out: @@ -998,8 +1019,6 @@ out: free(buf); free(command); 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) {