xref: /openbsd-src/usr.bin/ssh/misc.h (revision 24bb5fcea3ed904bc467217bdaadb5dfc618d5bf)
1 /* $OpenBSD: misc.h,v 1.97 2021/06/08 06:54:40 djm Exp $ */
2 
3 /*
4  * Author: Tatu Ylonen <ylo@cs.hut.fi>
5  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6  *                    All rights reserved
7  *
8  * As far as I am concerned, the code I have written for this software
9  * can be used freely for any purpose.  Any derived versions of this
10  * software must be clearly marked as such, and if the derived work is
11  * incompatible with the protocol description in the RFC file, it must be
12  * called by a name other than "ssh" or "Secure Shell".
13  */
14 
15 #ifndef _MISC_H
16 #define _MISC_H
17 
18 #include <sys/time.h>
19 #include <sys/types.h>
20 #include <sys/socket.h>
21 #include <stdio.h>
22 
23 /* Data structure for representing a forwarding request. */
24 struct Forward {
25 	char	 *listen_host;		/* Host (address) to listen on. */
26 	int	  listen_port;		/* Port to forward. */
27 	char	 *listen_path;		/* Path to bind domain socket. */
28 	char	 *connect_host;		/* Host to connect. */
29 	int	  connect_port;		/* Port to connect on connect_host. */
30 	char	 *connect_path;		/* Path to connect domain socket. */
31 	int	  allocated_port;	/* Dynamically allocated listen port */
32 	int	  handle;		/* Handle for dynamic listen ports */
33 };
34 
35 int forward_equals(const struct Forward *, const struct Forward *);
36 int daemonized(void);
37 
38 /* Common server and client forwarding options. */
39 struct ForwardOptions {
40 	int	 gateway_ports; /* Allow remote connects to forwarded ports. */
41 	mode_t	 streamlocal_bind_mask; /* umask for streamlocal binds */
42 	int	 streamlocal_bind_unlink; /* unlink socket before bind */
43 };
44 
45 /* misc.c */
46 
47 char	*chop(char *);
48 void	 rtrim(char *);
49 void	skip_space(char **);
50 char	*strdelim(char **);
51 char	*strdelimw(char **);
52 int	 set_nonblock(int);
53 int	 unset_nonblock(int);
54 void	 set_nodelay(int);
55 int	 set_reuseaddr(int);
56 char	*get_rdomain(int);
57 int	 set_rdomain(int, const char *);
58 int	 get_sock_af(int);
59 void	 set_sock_tos(int, int);
60 int	 waitrfd(int, int *);
61 int	 timeout_connect(int, const struct sockaddr *, socklen_t, int *);
62 int	 a2port(const char *);
63 int	 a2tun(const char *, int *);
64 char	*put_host_port(const char *, u_short);
65 char	*hpdelim2(char **, char *);
66 char	*hpdelim(char **);
67 char	*cleanhostname(char *);
68 char	*colon(char *);
69 int	 parse_user_host_path(const char *, char **, char **, char **);
70 int	 parse_user_host_port(const char *, char **, char **, int *);
71 int	 parse_uri(const char *, const char *, char **, char **, int *, char **);
72 int	 convtime(const char *);
73 const char *fmt_timeframe(time_t t);
74 char	*tilde_expand_filename(const char *, uid_t);
75 
76 char	*dollar_expand(int *, const char *string, ...);
77 char	*percent_expand(const char *, ...) __attribute__((__sentinel__));
78 char	*percent_dollar_expand(const char *, ...) __attribute__((__sentinel__));
79 char	*tohex(const void *, size_t);
80 void	 xextendf(char **s, const char *sep, const char *fmt, ...)
81     __attribute__((__format__ (printf, 3, 4))) __attribute__((__nonnull__ (3)));
82 void	 sanitise_stdfd(void);
83 void	 ms_subtract_diff(struct timeval *, int *);
84 void	 ms_to_timeval(struct timeval *, int);
85 void	 monotime_ts(struct timespec *);
86 void	 monotime_tv(struct timeval *);
87 time_t	 monotime(void);
88 double	 monotime_double(void);
89 void	 lowercase(char *s);
90 int	 unix_listener(const char *, int, int);
91 int	 valid_domain(char *, int, const char **);
92 int	 valid_env_name(const char *);
93 const char *atoi_err(const char *, int *);
94 int	 parse_absolute_time(const char *, uint64_t *);
95 void	 format_absolute_time(uint64_t, char *, size_t);
96 int	 path_absolute(const char *);
97 int	 stdfd_devnull(int, int, int);
98 
99 struct passwd *pwcopy(struct passwd *);
100 const char *ssh_gai_strerror(int);
101 
102 typedef void privdrop_fn(struct passwd *);
103 typedef void privrestore_fn(void);
104 #define	SSH_SUBPROCESS_STDOUT_DISCARD	(1)     /* Discard stdout */
105 #define	SSH_SUBPROCESS_STDOUT_CAPTURE	(1<<1)  /* Redirect stdout */
106 #define	SSH_SUBPROCESS_STDERR_DISCARD	(1<<2)  /* Discard stderr */
107 #define	SSH_SUBPROCESS_UNSAFE_PATH	(1<<3)	/* Don't check for safe cmd */
108 #define	SSH_SUBPROCESS_PRESERVE_ENV	(1<<4)	/* Keep parent environment */
109 pid_t subprocess(const char *, const char *, int, char **, FILE **, u_int,
110     struct passwd *, privdrop_fn *, privrestore_fn *);
111 
112 typedef struct arglist arglist;
113 struct arglist {
114 	char    **list;
115 	u_int   num;
116 	u_int   nalloc;
117 };
118 void	 addargs(arglist *, char *, ...)
119 	    __attribute__((format(printf, 2, 3)));
120 void	 replacearg(arglist *, u_int, char *, ...)
121 	    __attribute__((format(printf, 3, 4)));
122 void	 freeargs(arglist *);
123 
124 int	 tun_open(int, int, char **);
125 
126 /* Common definitions for ssh tunnel device forwarding */
127 #define SSH_TUNMODE_NO		0x00
128 #define SSH_TUNMODE_POINTOPOINT	0x01
129 #define SSH_TUNMODE_ETHERNET	0x02
130 #define SSH_TUNMODE_DEFAULT	SSH_TUNMODE_POINTOPOINT
131 #define SSH_TUNMODE_YES		(SSH_TUNMODE_POINTOPOINT|SSH_TUNMODE_ETHERNET)
132 
133 #define SSH_TUNID_ANY		0x7fffffff
134 #define SSH_TUNID_ERR		(SSH_TUNID_ANY - 1)
135 #define SSH_TUNID_MAX		(SSH_TUNID_ANY - 2)
136 
137 /* Fake port to indicate that host field is really a path. */
138 #define PORT_STREAMLOCAL	-2
139 
140 /* Functions to extract or store big-endian words of various sizes */
141 u_int64_t	get_u64(const void *)
142     __attribute__((__bounded__( __minbytes__, 1, 8)));
143 u_int32_t	get_u32(const void *)
144     __attribute__((__bounded__( __minbytes__, 1, 4)));
145 u_int16_t	get_u16(const void *)
146     __attribute__((__bounded__( __minbytes__, 1, 2)));
147 void		put_u64(void *, u_int64_t)
148     __attribute__((__bounded__( __minbytes__, 1, 8)));
149 void		put_u32(void *, u_int32_t)
150     __attribute__((__bounded__( __minbytes__, 1, 4)));
151 void		put_u16(void *, u_int16_t)
152     __attribute__((__bounded__( __minbytes__, 1, 2)));
153 
154 /* Little-endian store/load, used by umac.c */
155 u_int32_t	get_u32_le(const void *)
156     __attribute__((__bounded__(__minbytes__, 1, 4)));
157 void		put_u32_le(void *, u_int32_t)
158     __attribute__((__bounded__(__minbytes__, 1, 4)));
159 
160 struct bwlimit {
161 	size_t buflen;
162 	u_int64_t rate;		/* desired rate in kbit/s */
163 	u_int64_t thresh;	/* threshold after which we'll check timers */
164 	u_int64_t lamt;		/* amount written in last timer interval */
165 	struct timeval bwstart, bwend;
166 };
167 
168 void bandwidth_limit_init(struct bwlimit *, u_int64_t, size_t);
169 void bandwidth_limit(struct bwlimit *, size_t);
170 
171 int parse_ipqos(const char *);
172 const char *iptos2str(int);
173 void mktemp_proto(char *, size_t);
174 
175 void	 child_set_env(char ***envp, u_int *envsizep, const char *name,
176 	    const char *value);
177 const char *lookup_env_in_list(const char *env,
178 	    char * const *envs, size_t nenvs);
179 
180 int	 argv_split(const char *, int *, char ***, int);
181 char	*argv_assemble(int, char **argv);
182 char	*argv_next(int *, char ***);
183 void	 argv_consume(int *);
184 void	 argv_free(char **, int);
185 
186 int	 exited_cleanly(pid_t, const char *, const char *, int);
187 
188 struct stat;
189 int	 safe_path(const char *, struct stat *, const char *, uid_t,
190 	    char *, size_t);
191 int	 safe_path_fd(int, const char *, struct passwd *,
192 	    char *err, size_t errlen);
193 
194 /* authorized_key-style options parsing helpers */
195 int	opt_flag(const char *opt, int allow_negate, const char **optsp);
196 char	*opt_dequote(const char **sp, const char **errstrp);
197 int	opt_match(const char **opts, const char *term);
198 
199 /* readconf/servconf option lists */
200 void	opt_array_append(const char *file, const int line,
201 	    const char *directive, char ***array, u_int *lp, const char *s);
202 void	opt_array_append2(const char *file, const int line,
203 	    const char *directive, char ***array, int **iarray, u_int *lp,
204 	    const char *s, int i);
205 
206 /* readpass.c */
207 
208 #define RP_ECHO			0x0001
209 #define RP_ALLOW_STDIN		0x0002
210 #define RP_ALLOW_EOF		0x0004
211 #define RP_USE_ASKPASS		0x0008
212 
213 struct notifier_ctx;
214 
215 char	*read_passphrase(const char *, int);
216 int	 ask_permission(const char *, ...) __attribute__((format(printf, 1, 2)));
217 struct notifier_ctx *notify_start(int, const char *, ...)
218 	__attribute__((format(printf, 2, 3)));
219 void	notify_complete(struct notifier_ctx *, const char *, ...)
220 	__attribute__((format(printf, 2, 3)));
221 
222 #define MINIMUM(a, b)	(((a) < (b)) ? (a) : (b))
223 #define MAXIMUM(a, b)	(((a) > (b)) ? (a) : (b))
224 #define ROUNDUP(x, y)   ((((x)+((y)-1))/(y))*(y))
225 
226 typedef void (*sshsig_t)(int);
227 sshsig_t ssh_signal(int, sshsig_t);
228 
229 #endif /* _MISC_H */
230