cli.c

/*
 * Functions dedicated to statistics output and the stats socket
 *
 * Copyright 2000-2012 Willy Tarreau <w@1wt.eu>
 * Copyright 2007-2009 Krzysztof Piotr Oledzki <ole@ans.pl>
 *
 * 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.
 *
 */

#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pwd.h>
#include <grp.h>

#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>

#include <net/if.h>

#include <haproxy/api.h>
#include <haproxy/applet.h>
#include <haproxy/base64.h>
#include <haproxy/cfgparse.h>
#include <haproxy/channel.h>
#include <haproxy/check.h>
#include <haproxy/cli.h>
#include <haproxy/compression.h>
#include <haproxy/dns-t.h>
#include <haproxy/errors.h>
#include <haproxy/fd.h>
#include <haproxy/freq_ctr.h>
#include <haproxy/frontend.h>
#include <haproxy/global.h>
#include <haproxy/list.h>
#include <haproxy/listener.h>
#include <haproxy/log.h>
#include <haproxy/mworker.h>
#include <haproxy/mworker-t.h>
#include <haproxy/pattern-t.h>
#include <haproxy/peers.h>
#include <haproxy/pipe.h>
#include <haproxy/protocol.h>
#include <haproxy/proxy.h>
#include <haproxy/quic_sock.h>
#include <haproxy/sample-t.h>
#include <haproxy/sc_strm.h>
#include <haproxy/server.h>
#include <haproxy/session.h>
#include <haproxy/sock.h>
#include <haproxy/stats-t.h>
#include <haproxy/stconn.h>
#include <haproxy/stream.h>
#include <haproxy/task.h>
#include <haproxy/ticks.h>
#include <haproxy/time.h>
#include <haproxy/tools.h>
#include <haproxy/version.h>

#define PAYLOAD_PATTERN "<<"

static struct applet cli_applet;
static struct applet mcli_applet;

static const char cli_permission_denied_msg[] =
	"Permission denied\n"
	"";


static THREAD_LOCAL char *dynamic_usage_msg = NULL;

/* List head of cli keywords */
static struct cli_kw_list cli_keywords = {
	.list = LIST_HEAD_INIT(cli_keywords.list)
};

extern const char *stat_status_codes[];

struct proxy *mworker_proxy; /* CLI proxy of the master */
struct bind_conf *mcli_reload_bind_conf;

/* CLI context for the "show env" command */
struct show_env_ctx {
	char **var;      /* first variable to show */
	int show_one;    /* stop after showing the first one */
};

/* CLI context for the "show fd" command */
/* flags for show_fd_ctx->show_mask */
#define CLI_SHOWFD_F_PI  0x00000001   /* pipes             */
#define CLI_SHOWFD_F_LI  0x00000002   /* listeners         */
#define CLI_SHOWFD_F_FE  0x00000004   /* frontend conns    */
#define CLI_SHOWFD_F_SV  0x00000010   /* server-only conns */
#define CLI_SHOWFD_F_PX  0x00000020   /* proxy-only conns  */
#define CLI_SHOWFD_F_BE  0x00000030   /* backend: srv+px   */
#define CLI_SHOWFD_F_CO  0x00000034   /* conn: be+fe       */
#define CLI_SHOWFD_F_ANY 0x0000003f   /* any type          */

struct show_fd_ctx {
	int fd;          /* first FD to show */
	int show_one;    /* stop after showing one FD */
	uint show_mask;  /* CLI_SHOWFD_F_xxx */
};

/* CLI context for the "show cli sockets" command */
struct show_sock_ctx {
	struct bind_conf *bind_conf;
	struct listener *listener;
};

static int cmp_kw_entries(const void *a, const void *b)
{
	const struct cli_kw *l = *(const struct cli_kw **)a;
	const struct cli_kw *r = *(const struct cli_kw **)b;

	return strcmp(l->usage ? l->usage : "", r->usage ? r->usage : "");
}

/* This will show the help message and list the commands supported at the
 * current level that match all of the first words of <args> if args is not
 * NULL, or all args if none matches or if args is null.
 */
static char *cli_gen_usage_msg(struct appctx *appctx, char * const *args)
{
	struct cli_kw *entries[CLI_MAX_HELP_ENTRIES];
	struct cli_kw_list *kw_list;
	struct cli_kw *kw;
	struct buffer *tmp = get_trash_chunk();
	struct buffer out;
	struct { struct cli_kw *kw; int dist; } matches[CLI_MAX_MATCHES], swp;
	int idx;
	int ishelp = 0;
	int length = 0;
	int help_entries = 0;

	ha_free(&dynamic_usage_msg);

	if (args && *args && strcmp(*args, "help") == 0) {
		args++;
		ishelp = 1;
	}

	/* first, let's measure the longest match */
	list_for_each_entry(kw_list, &cli_keywords.list, list) {
		for (kw = &kw_list->kw[0]; kw->str_kw[0]; kw++) {
			if (kw->level & ~appctx->cli_level & (ACCESS_MASTER_ONLY|ACCESS_EXPERT|ACCESS_EXPERIMENTAL))
				continue;
			if (!(appctx->cli_level & ACCESS_MCLI_DEBUG) &&
			    (appctx->cli_level & ~kw->level & (ACCESS_MASTER_ONLY|ACCESS_MASTER)) ==
			    (ACCESS_MASTER_ONLY|ACCESS_MASTER))
				continue;

			/* OK this command is visible */
			for (idx = 0; idx < CLI_PREFIX_KW_NB; idx++) {
				if (!kw->str_kw[idx])
					break; // end of keyword
				if (!args || !args[idx] || !*args[idx])
					break; // end of command line
				if (strcmp(kw->str_kw[idx], args[idx]) != 0)
					break;
				if (idx + 1 > length)
					length = idx + 1;
			}
		}
	}

	/* now <length> equals the number of exactly matching words */
	chunk_reset(tmp);
	if (ishelp) // this is the help message.
		chunk_strcat(tmp, "The following commands are valid at this level:\n");
	else {
		chunk_strcat(tmp, "Unknown command: '");
		if (args && *args)
			chunk_strcat(tmp, *args);
		chunk_strcat(tmp, "'");

		if (!length && (!args || !*args || !**args)) // no match
			chunk_strcat(tmp, ". Please enter one of the following commands only:\n");
		else // partial match
			chunk_strcat(tmp, ", but maybe one of the following ones is a better match:\n");
	}

	for (idx = 0; idx < CLI_MAX_MATCHES; idx++) {
		matches[idx].kw = NULL;
		matches[idx].dist = INT_MAX;
	}

	/* In case of partial match we'll look for the best matching entries
	 * starting from position <length>
	 */
	if (args && args[length] && *args[length]) {
		list_for_each_entry(kw_list, &cli_keywords.list, list) {
			for (kw = &kw_list->kw[0]; kw->str_kw[0]; kw++) {
				if (kw->level & ~appctx->cli_level & (ACCESS_MASTER_ONLY|ACCESS_EXPERT|ACCESS_EXPERIMENTAL))
					continue;
				if (!(appctx->cli_level & ACCESS_MCLI_DEBUG) &&
				    ((appctx->cli_level & ~kw->level & (ACCESS_MASTER_ONLY|ACCESS_MASTER)) ==
				    (ACCESS_MASTER_ONLY|ACCESS_MASTER)))
					continue;

				for (idx = 0; idx < length; idx++) {
					if (!kw->str_kw[idx])
						break; // end of keyword
					if (!args || !args[idx] || !*args[idx])
						break; // end of command line
					if (strcmp(kw->str_kw[idx], args[idx]) != 0)
						break;
				}

				/* extra non-matching words are fuzzy-matched */
				if (kw->usage && idx == length && args[idx] && *args[idx]) {
					uint8_t word_sig[1024];
					uint8_t list_sig[1024];
					int dist = 0;
					int totlen = 0;
					int i;

					/* this one matches, let's compute the distance between the two
					 * on the remaining words. For this we're computing the signature
					 * of everything that remains and the cumulated length of the
					 * strings.
					 */
					memset(word_sig, 0, sizeof(word_sig));
					for (i = idx; i < CLI_PREFIX_KW_NB && args[i] && *args[i]; i++) {
						update_word_fingerprint(word_sig, args[i]);
						totlen += strlen(args[i]);
					}

					memset(list_sig, 0, sizeof(list_sig));
					for (i = idx; i < CLI_PREFIX_KW_NB && kw->str_kw[i]; i++) {
						update_word_fingerprint(list_sig, kw->str_kw[i]);
						totlen += strlen(kw->str_kw[i]);
					}

					dist = word_fingerprint_distance(word_sig, list_sig);

					/* insert this one at its place if relevant, in order to keep only
					 * the best matches.
					 */
					swp.kw = kw; swp.dist = dist;
					if (dist < 5*totlen/2 && dist < matches[CLI_MAX_MATCHES-1].dist) {
						matches[CLI_MAX_MATCHES-1] = swp;
						for (idx = CLI_MAX_MATCHES - 1; --idx >= 0;) {
							if (matches[idx+1].dist >= matches[idx].dist)
								break;
							matches[idx+1] = matches[idx];
							matches[idx] = swp;
						}
					}
				}
			}
		}
	}

	if (matches[0].kw) {
		/* we have fuzzy matches, let's propose them */
		for (idx = 0; idx < CLI_MAX_MATCHES; idx++) {
			kw = matches[idx].kw;
			if (!kw)
				break;

			/* stop the dump if some words look very unlikely candidates */
			if (matches[idx].dist > 5*matches[0].dist/2)
				break;

			if (help_entries < CLI_MAX_HELP_ENTRIES)
				entries[help_entries++] = kw;
		}
	}

	list_for_each_entry(kw_list, &cli_keywords.list, list) {
		/* no full dump if we've already found nice candidates */
		if (matches[0].kw)
			break;

		for (kw = &kw_list->kw[0]; kw->str_kw[0]; kw++) {

			/* in a worker or normal process, don't display master-only commands
			 * nor expert/experimental mode commands if not in this mode.
			 */
			if (kw->level & ~appctx->cli_level & (ACCESS_MASTER_ONLY|ACCESS_EXPERT|ACCESS_EXPERIMENTAL))
				continue;

			/* in master, if the CLI don't have the
			 * ACCESS_MCLI_DEBUG don't display commands that have
			 * neither the master bit nor the master-only bit.
			 */
			if (!(appctx->cli_level & ACCESS_MCLI_DEBUG) &&
			    ((appctx->cli_level & ~kw->level & (ACCESS_MASTER_ONLY|ACCESS_MASTER)) ==
			    (ACCESS_MASTER_ONLY|ACCESS_MASTER)))
				continue;

			for (idx = 0; idx < length; idx++) {
				if (!kw->str_kw[idx])
					break; // end of keyword
				if (!args || !args[idx] || !*args[idx])
					break; // end of command line
				if (strcmp(kw->str_kw[idx], args[idx]) != 0)
					break;
			}

			if (kw->usage && idx == length && help_entries < CLI_MAX_HELP_ENTRIES)
				entries[help_entries++] = kw;
		}
	}

	qsort(entries, help_entries, sizeof(*entries), cmp_kw_entries);

	for (idx = 0; idx < help_entries; idx++)
		chunk_appendf(tmp, "  %s\n", entries[idx]->usage);

	/* always show the prompt/help/quit commands */
	chunk_strcat(tmp,
	             "  help [<command>]                        : list matching or all commands\n"
	             "  prompt [timed]                          : toggle interactive mode with prompt\n"
	             "  quit                                    : disconnect\n");

	chunk_init(&out, NULL, 0);
	chunk_dup(&out, tmp);
	dynamic_usage_msg = out.area;

	cli_msg(appctx, LOG_INFO, dynamic_usage_msg);
	return dynamic_usage_msg;
}

struct cli_kw* cli_find_kw(char **args)
{
	struct cli_kw_list *kw_list;
	struct cli_kw *kw;/* current cli_kw */
	char **tmp_args;
	const char **tmp_str_kw;
	int found = 0;

	if (LIST_ISEMPTY(&cli_keywords.list))
		return NULL;

	list_for_each_entry(kw_list, &cli_keywords.list, list) {
		kw = &kw_list->kw[0];
		while (*kw->str_kw) {
			tmp_args = args;
			tmp_str_kw = kw->str_kw;
			while (*tmp_str_kw) {
				if (strcmp(*tmp_str_kw, *tmp_args) == 0) {
					found = 1;
				} else {
					found = 0;
					break;
				}
				tmp_args++;
				tmp_str_kw++;
			}
			if (found)
				return (kw);
			kw++;
		}
	}
	return NULL;
}

struct cli_kw* cli_find_kw_exact(char **args)
{
	struct cli_kw_list *kw_list;
	int found = 0;
	int i;
	int j;

	if (LIST_ISEMPTY(&cli_keywords.list))
		return NULL;

	list_for_each_entry(kw_list, &cli_keywords.list, list) {
		for (i = 0; kw_list->kw[i].str_kw[0]; i++) {
			found = 1;
			for (j = 0; j < CLI_PREFIX_KW_NB; j++) {
				if (args[j] == NULL && kw_list->kw[i].str_kw[j] == NULL) {
					break;
				}
				if (args[j] == NULL || kw_list->kw[i].str_kw[j] == NULL) {
					found = 0;
					break;
				}
				if (strcmp(args[j], kw_list->kw[i].str_kw[j]) != 0) {
					found = 0;
					break;
				}
			}
			if (found)
				return &kw_list->kw[i];
		}
	}
	return NULL;
}

void cli_register_kw(struct cli_kw_list *kw_list)
{
	LIST_APPEND(&cli_keywords.list, &kw_list->list);
}

/* list all known keywords on stdout, one per line */
void cli_list_keywords(void)
{
	struct cli_kw_list *kw_list;
	struct cli_kw *kwp, *kwn, *kw;
	int idx;

	for (kwn = kwp = NULL;; kwp = kwn) {
		list_for_each_entry(kw_list, &cli_keywords.list, list) {
			/* note: we sort based on the usage message when available,
			 * otherwise we fall back to the first keyword.
			 */
			for (kw = &kw_list->kw[0]; kw->str_kw[0]; kw++) {
				if (strordered(kwp ? kwp->usage ? kwp->usage : kwp->str_kw[0] : NULL,
					       kw->usage ? kw->usage : kw->str_kw[0],
					       kwn != kwp ? kwn->usage ? kwn->usage : kwn->str_kw[0] : NULL))
					kwn = kw;
			}
		}

		if (kwn == kwp)
			break;

		for (idx = 0; kwn->str_kw[idx]; idx++) {
			printf("%s ", kwn->str_kw[idx]);
		}
		if (kwn->level & (ACCESS_MASTER_ONLY|ACCESS_MASTER))
			printf("[MASTER] ");
		if (!(kwn->level & ACCESS_MASTER_ONLY))
			printf("[WORKER] ");
		if (kwn->level & ACCESS_EXPERT)
			printf("[EXPERT] ");
		if (kwn->level & ACCESS_EXPERIMENTAL)
			printf("[EXPERIM] ");
		printf("\n");
	}
}

/* allocate a new stats frontend named <name>, and return it
 * (or NULL in case of lack of memory).
 */
static struct proxy *cli_alloc_fe(const char *name, const char *file, int line)
{
	struct proxy *fe;

	fe = calloc(1, sizeof(*fe));
	if (!fe)
		return NULL;

	init_new_proxy(fe);
	fe->next = proxies_list;
	proxies_list = fe;
	fe->last_change = ns_to_sec(now_ns);
	fe->id = strdup("GLOBAL");
	fe->cap = PR_CAP_FE|PR_CAP_INT;
	fe->maxconn = 10;                 /* default to 10 concurrent connections */
	fe->timeout.client = MS_TO_TICKS(10000); /* default timeout of 10 seconds */
	fe->conf.file = strdup(file);
	fe->conf.line = line;
	fe->accept = frontend_accept;
	fe->default_target = &cli_applet.obj_type;

	/* the stats frontend is the only one able to assign ID #0 */
	fe->conf.id.key = fe->uuid = 0;
	eb32_insert(&used_proxy_id, &fe->conf.id);
	return fe;
}

/* This function parses a "stats" statement in the "global" section. It returns
 * -1 if there is any error, otherwise zero. If it returns -1, it will write an
 * error message into the <err> buffer which will be preallocated. The trailing
 * '\n' must not be written. The function must be called with <args> pointing to
 * the first word after "stats".
 */
static int cli_parse_global(char **args, int section_type, struct proxy *curpx,
                            const struct proxy *defpx, const char *file, int line,
                            char **err)
{
	struct bind_conf *bind_conf;
	struct listener *l;

	if (strcmp(args[1], "socket") == 0) {
		int cur_arg;

		if (*args[2] == 0) {
			memprintf(err, "'%s %s' in global section expects an address or a path to a UNIX socket", args[0], args[1]);
			return -1;
		}

		if (!global.cli_fe) {
			if ((global.cli_fe = cli_alloc_fe("GLOBAL", file, line)) == NULL) {
				memprintf(err, "'%s %s' : out of memory trying to allocate a frontend", args[0], args[1]);
				return -1;
			}
		}

		bind_conf = bind_conf_alloc(global.cli_fe, file, line, args[2], xprt_get(XPRT_RAW));
		if (!bind_conf) {
			memprintf(err, "'%s %s' : out of memory trying to allocate a bind_conf", args[0], args[1]);
			return -1;
		}
		bind_conf->level &= ~ACCESS_LVL_MASK;
		bind_conf->level |= ACCESS_LVL_OPER; /* default access level */

		if (!str2listener(args[2], global.cli_fe, bind_conf, file, line, err)) {
			memprintf(err, "parsing [%s:%d] : '%s %s' : %s\n",
			          file, line, args[0], args[1], err && *err ? *err : "error");
			return -1;
		}

		cur_arg = 3;
		while (*args[cur_arg]) {
			struct bind_kw *kw;
			const char *best;
			int code;

			kw = bind_find_kw(args[cur_arg]);
			if (kw) {
				if (!kw->parse) {
					memprintf(err, "'%s %s' : '%s' option is not implemented in this version (check build options).",
						  args[0], args[1], args[cur_arg]);
					return -1;
				}

				code = kw->parse(args, cur_arg, global.cli_fe, bind_conf, err);

				/* FIXME: this is ugly, we don't have a way to collect warnings,
				 * yet some important bind keywords may report warnings that we
				 * must display.
				 */
				if (((code & (ERR_WARN|ERR_FATAL|ERR_ALERT)) == ERR_WARN) && err && *err) {
					indent_msg(err, 2);
					ha_warning("parsing [%s:%d] : '%s %s' : %s\n", file, line, args[0], args[1], *err);
					ha_free(err);
				}

				if (code & ~ERR_WARN) {
					if (err && *err)
						memprintf(err, "'%s %s' : '%s'", args[0], args[1], *err);
					else
						memprintf(err, "'%s %s' : error encountered while processing '%s'",
						          args[0], args[1], args[cur_arg]);
					return -1;
				}

				cur_arg += 1 + kw->skip;
				continue;
			}

			best = bind_find_best_kw(args[cur_arg]);
			if (best)
				memprintf(err, "'%s %s' : unknown keyword '%s'. Did you mean '%s' maybe ?",
				          args[0], args[1], args[cur_arg], best);
			else
				memprintf(err, "'%s %s' : unknown keyword '%s'.",
				          args[0], args[1], args[cur_arg]);
			return -1;
		}

		bind_conf->accept = session_accept_fd;
		bind_conf->nice = -64;  /* we want to boost priority for local stats */
		bind_conf->options |= BC_O_UNLIMITED; /* don't make the peers subject to global limits */

		list_for_each_entry(l, &bind_conf->listeners, by_bind) {
			global.maxsock++; /* for the listening socket */
		}
	}
	else if (strcmp(args[1], "timeout") == 0) {
		unsigned timeout;
		const char *res = parse_time_err(args[2], &timeout, TIME_UNIT_MS);

		if (res == PARSE_TIME_OVER) {
			memprintf(err, "timer overflow in argument '%s' to '%s %s' (maximum value is 2147483647 ms or ~24.8 days)",
				 args[2], args[0], args[1]);
			return -1;
		}
		else if (res == PARSE_TIME_UNDER) {
			memprintf(err, "timer underflow in argument '%s' to '%s %s' (minimum non-null value is 1 ms)",
				 args[2], args[0], args[1]);
			return -1;
		}
		else if (res) {
			memprintf(err, "'%s %s' : unexpected character '%c'", args[0], args[1], *res);
			return -1;
		}

		if (!timeout) {
			memprintf(err, "'%s %s' expects a positive value", args[0], args[1]);
			return -1;
		}
		if (!global.cli_fe) {
			if ((global.cli_fe = cli_alloc_fe("GLOBAL", file, line)) == NULL) {
				memprintf(err, "'%s %s' : out of memory trying to allocate a frontend", args[0], args[1]);
				return -1;
			}
		}
		global.cli_fe->timeout.client = MS_TO_TICKS(timeout);
	}
	else if (strcmp(args[1], "maxconn") == 0) {
		int maxconn = atol(args[2]);

		if (maxconn <= 0) {
			memprintf(err, "'%s %s' expects a positive value", args[0], args[1]);
			return -1;
		}

		if (!global.cli_fe) {
			if ((global.cli_fe = cli_alloc_fe("GLOBAL", file, line)) == NULL) {
				memprintf(err, "'%s %s' : out of memory trying to allocate a frontend", args[0], args[1]);
				return -1;
			}
		}
		global.cli_fe->maxconn = maxconn;
	}
	else if (strcmp(args[1], "bind-process") == 0) {
		memprintf(err, "'%s %s' is not supported anymore.", args[0], args[1]);
		return -1;
	}
	else {
		memprintf(err, "'%s' only supports 'socket', 'maxconn', 'bind-process' and 'timeout' (got '%s')", args[0], args[1]);
		return -1;
	}
	return 0;
}

/*
 * This function exports the bound addresses of a <frontend> in the environment
 * variable <varname>. Those addresses are separated by semicolons and prefixed
 * with their type (abns@, unix@, sockpair@ etc)
 * Return -1 upon error, 0 otherwise
 */
int listeners_setenv(struct proxy *frontend, const char *varname)
{
	struct buffer *trash = get_trash_chunk();
	struct bind_conf *bind_conf;

	if (frontend) {
		list_for_each_entry(bind_conf, &frontend->conf.bind, by_fe) {
			struct listener *l;

			list_for_each_entry(l, &bind_conf->listeners, by_bind) {
				char addr[46];
				char port[6];

				/* separate listener by semicolons */
				if (trash->data)
					chunk_appendf(trash, ";");

				if (l->rx.addr.ss_family == AF_UNIX) {
					const struct sockaddr_un *un;

					un = (struct sockaddr_un *)&l->rx.addr;
					if (un->sun_path[0] == '\0') {
						chunk_appendf(trash, "abns@%s", un->sun_path+1);
					} else {
						chunk_appendf(trash, "unix@%s", un->sun_path);
					}
				} else if (l->rx.addr.ss_family == AF_INET) {
					addr_to_str(&l->rx.addr, addr, sizeof(addr));
					port_to_str(&l->rx.addr, port, sizeof(port));
					chunk_appendf(trash, "ipv4@%s:%s", addr, port);
				} else if (l->rx.addr.ss_family == AF_INET6) {
					addr_to_str(&l->rx.addr, addr, sizeof(addr));
					port_to_str(&l->rx.addr, port, sizeof(port));
					chunk_appendf(trash, "ipv6@[%s]:%s", addr, port);
				} else if (l->rx.addr.ss_family == AF_CUST_SOCKPAIR) {
					chunk_appendf(trash, "sockpair@%d", ((struct sockaddr_in *)&l->rx.addr)->sin_addr.s_addr);
				}
			}
		}
		trash->area[trash->data++] = '\0';
		if (setenv(varname, trash->area, 1) < 0)
			return -1;
	}

	return 0;
}

int cli_socket_setenv()
{
	if (listeners_setenv(global.cli_fe, "HAPROXY_CLI") < 0)
		return -1;
	if (listeners_setenv(mworker_proxy, "HAPROXY_MASTER_CLI") < 0)
		return -1;

	return 0;
}

REGISTER_CONFIG_POSTPARSER("cli", cli_socket_setenv);

/* Verifies that the CLI at least has a level at least as high as <level>
 * (typically ACCESS_LVL_ADMIN). Returns 1 if OK, otherwise 0. In case of
 * failure, an error message is prepared and the appctx's state is adjusted
 * to print it so that a return 1 is enough to abort any processing.
 */
int cli_has_level(struct appctx *appctx, int level)
{

	if ((appctx->cli_level & ACCESS_LVL_MASK) < level) {
		cli_err(appctx, cli_permission_denied_msg);
		return 0;
	}
	return 1;
}

/* same as cli_has_level but for the CLI proxy and without error message */
int pcli_has_level(struct stream *s, int level)
{
	if ((s->pcli_flags & ACCESS_LVL_MASK) < level) {
		return 0;
	}
	return 1;
}

/* Returns severity_output for the current session if set, or default for the socket */
static int cli_get_severity_output(struct appctx *appctx)
{
	if (appctx->cli_severity_output)
		return appctx->cli_severity_output;
	return strm_li(appctx_strm(appctx))->bind_conf->severity_output;
}

/* Processes the CLI interpreter on the stats socket. This function is called
 * from the CLI's IO handler running in an appctx context. The function returns
 * 1 if the request was understood, otherwise zero (in which case an error
 * message will be displayed). It is called with appctx->st0
 * set to CLI_ST_GETREQ and presets ->st2 to 0 so that parsers don't have to do
 * it. It will possilbly leave st0 to CLI_ST_CALLBACK if the keyword needs to
 * have its own I/O handler called again. Most of the time, parsers will only
 * set st0 to CLI_ST_PRINT and put their message to be displayed into cli.msg.
 * If a keyword parser is NULL and an I/O handler is declared, the I/O handler
 * will automatically be used.
 */
static int cli_parse_request(struct appctx *appctx)
{
	char *args[MAX_CLI_ARGS + 1], *p, *end, *payload = NULL;
	int i = 0;
	struct cli_kw *kw;

	p = appctx->chunk->area;
	end = p + appctx->chunk->data;

	/*
	 * Get pointers on words.
	 * One extra slot is reserved to store a pointer on a null byte.
	 */
	while (i < MAX_CLI_ARGS && p < end) {
		int j, k;

		/* skip leading spaces/tabs */
		p += strspn(p, " \t");
		if (!*p)
			break;

		if (strcmp(p, PAYLOAD_PATTERN) == 0) {
			/* payload pattern recognized here, this is not an arg anymore,
			 * the payload starts at the first byte that follows the zero
			 * after the pattern.
			 */
			payload = p + strlen(PAYLOAD_PATTERN) + 1;
			break;
		}

		args[i] = p;
		while (1) {
			p += strcspn(p, " \t\\");
			/* escaped chars using backlashes (\) */
			if (*p == '\\') {
				if (!*++p)
					break;
				if (!*++p)
					break;
			} else {
				break;
			}
		}
		*p++ = 0;

		/* unescape backslashes (\) */
		for (j = 0, k = 0; args[i][k]; k++) {
			if (args[i][k] == '\\') {
				if (args[i][k + 1] == '\\')
					k++;
				else
					continue;
			}
			args[i][j] = args[i][k];
			j++;
		}
		args[i][j] = 0;

		i++;
	}
	/* fill unused slots */
	p = appctx->chunk->area + appctx->chunk->data;
	for (; i < MAX_CLI_ARGS + 1; i++)
		args[i] = p;

	if (!**args)
		return 0;

	kw = cli_find_kw(args);
	if (!kw ||
	    (kw->level & ~appctx->cli_level & ACCESS_MASTER_ONLY) ||
	    (!(appctx->cli_level & ACCESS_MCLI_DEBUG) &&
	     (appctx->cli_level & ~kw->level & (ACCESS_MASTER_ONLY|ACCESS_MASTER)) == (ACCESS_MASTER_ONLY|ACCESS_MASTER))) {
		/* keyword not found in this mode */
		cli_gen_usage_msg(appctx, args);
		return 0;
	}

	/* don't handle expert mode commands if not in this mode. */
	if (kw->level & ~appctx->cli_level & ACCESS_EXPERT) {
		cli_err(appctx, "This command is restricted to expert mode only.\n");
		return 0;
	}

	if (kw->level & ~appctx->cli_level & ACCESS_EXPERIMENTAL) {
		cli_err(appctx, "This command is restricted to experimental mode only.\n");
		return 0;
	}

	if (kw->level == ACCESS_EXPERT)
		mark_tainted(TAINTED_CLI_EXPERT_MODE);
	else if (kw->level == ACCESS_EXPERIMENTAL)
		mark_tainted(TAINTED_CLI_EXPERIMENTAL_MODE);

	appctx->io_handler = kw->io_handler;
	appctx->io_release = kw->io_release;

	if (kw->parse && kw->parse(args, payload, appctx, kw->private) != 0)
		goto fail;

	/* kw->parse could set its own io_handler or io_release handler */
	if (!appctx->io_handler)
		goto fail;

	appctx->st0 = CLI_ST_CALLBACK;
	return 1;
fail:
	appctx->io_handler = NULL;
	appctx->io_release = NULL;
	return 1;
}

/* prepends then outputs the argument msg with a syslog-type severity depending on severity_output value */
static int cli_output_msg(struct appctx *appctx, const char *msg, int severity, int severity_output)
{
	struct buffer *tmp;

	if (likely(severity_output == CLI_SEVERITY_NONE))
		return applet_putstr(appctx, msg);

	tmp = get_trash_chunk();
	chunk_reset(tmp);

	if (severity < 0 || severity > 7) {
		ha_warning("socket command feedback with invalid severity %d", severity);
		chunk_printf(tmp, "[%d]: ", severity);
	}
	else {
		switch (severity_output) {
			case CLI_SEVERITY_NUMBER:
				chunk_printf(tmp, "[%d]: ", severity);
				break;
			case CLI_SEVERITY_STRING:
				chunk_printf(tmp, "[%s]: ", log_levels[severity]);
				break;
			default:
				ha_warning("Unrecognized severity output %d", severity_output);
		}
	}
	chunk_appendf(tmp, "%s", msg);

	return applet_putchk(appctx, tmp);
}

/* This I/O handler runs as an applet embedded in a stream connector. It is
 * used to processes I/O from/to the stats unix socket. The system relies on a
 * state machine handling requests and various responses. We read a request,
 * then we process it and send the response, and we possibly display a prompt.
 * Then we can read again. The state is stored in appctx->st0 and is one of the
 * CLI_ST_* constants. appctx->st1 is used to indicate whether prompt is enabled
 * or not.
 */
static void cli_io_handler(struct appctx *appctx)
{
	struct stconn *sc = appctx_sc(appctx);
	struct channel *req = sc_oc(sc);
	struct channel *res = sc_ic(sc);
	struct bind_conf *bind_conf = strm_li(__sc_strm(sc))->bind_conf;
	int reql;
	int len;

	if (unlikely(se_fl_test(appctx->sedesc, (SE_FL_EOS|SE_FL_ERROR|SE_FL_SHR|SE_FL_SHW)))) {
		co_skip(sc_oc(sc), co_data(sc_oc(sc)));
		goto out;
	}

	/* Check if the input buffer is available. */
	if (!b_size(&res->buf)) {
		sc_need_room(sc, 0);
		goto out;
	}

	while (1) {
		if (appctx->st0 == CLI_ST_INIT) {
			/* reset severity to default at init */
			appctx->cli_severity_output = bind_conf->severity_output;
			applet_reset_svcctx(appctx);
			appctx->st0 = CLI_ST_GETREQ;
			appctx->cli_level = bind_conf->level;
		}
		else if (appctx->st0 == CLI_ST_END) {
			se_fl_set(appctx->sedesc, SE_FL_EOS);
			free_trash_chunk(appctx->chunk);
			appctx->chunk = NULL;
			break;
		}
		else if (appctx->st0 == CLI_ST_GETREQ) {
			char *str;

			/* use a trash chunk to store received data */
			if (!appctx->chunk) {
				appctx->chunk = alloc_trash_chunk();
				if (!appctx->chunk) {
					se_fl_set(appctx->sedesc, SE_FL_ERROR);
					appctx->st0 = CLI_ST_END;
					continue;
				}
			}

			str = appctx->chunk->area + appctx->chunk->data;

			/* ensure we have some output room left in the event we
			 * would want to return some info right after parsing.
			 */
			if (buffer_almost_full(sc_ib(sc))) {
				sc_need_room(sc, b_size(&res->buf) / 2);
				break;
			}

			/* payload doesn't take escapes nor does it end on semi-colons, so
			 * we use the regular getline. Normal mode however must stop on
			 * LFs and semi-colons that are not prefixed by a backslash. Note
			 * that we reserve one byte at the end to insert a trailing nul byte.
			 */

			if (appctx->st1 & APPCTX_CLI_ST1_PAYLOAD)
				reql = co_getline(sc_oc(sc), str,
				                  appctx->chunk->size - appctx->chunk->data - 1);
			else
				reql = co_getdelim(sc_oc(sc), str,
				                   appctx->chunk->size - appctx->chunk->data - 1,
				                   "\n;", '\\');

			if (reql <= 0) { /* closed or EOL not found */
				if (reql == 0)
					break;
				se_fl_set(appctx->sedesc, SE_FL_ERROR);
				appctx->st0 = CLI_ST_END;
				continue;
			}

			if (!(appctx->st1 & APPCTX_CLI_ST1_PAYLOAD)) {
				/* seek for a possible unescaped semi-colon. If we find
				 * one, we replace it with an LF and skip only this part.
				 */
				for (len = 0; len < reql; len++) {
					if (str[len] == '\\') {
						len++;
						continue;
					}
					if (str[len] == ';') {
						str[len] = '\n';
						reql = len + 1;
						break;
					}
				}
			}

			/* now it is time to check that we have a full line,
			 * remove the trailing \n and possibly \r, then cut the
			 * line.
			 */
			len = reql - 1;
			if (str[len] != '\n') {
				se_fl_set(appctx->sedesc, SE_FL_ERROR);
				appctx->st0 = CLI_ST_END;
				continue;
			}

			if (len && str[len-1] == '\r')
				len--;