xref: /openssh-portable/misc.h (revision 31d8d231)
1 /* $OpenBSD: misc.h,v 1.95 2021/04/03 06:18:40 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	skip_space(char **);
49 char	*strdelim(char **);
50 char	*strdelimw(char **);
51 int	 set_nonblock(int);
52 int	 unset_nonblock(int);
53 void	 set_nodelay(int);
54 int	 set_reuseaddr(int);
55 char	*get_rdomain(int);
56 int	 set_rdomain(int, const char *);
57 int	 get_sock_af(int);
58 void	 set_sock_tos(int, int);
59 int	 waitrfd(int, int *);
60 int	 timeout_connect(int, const struct sockaddr *, socklen_t, int *);
61 int	 a2port(const char *);
62 int	 a2tun(const char *, int *);
63 char	*put_host_port(const char *, u_short);
64 char	*hpdelim2(char **, char *);
65 char	*hpdelim(char **);
66 char	*cleanhostname(char *);
67 char	*colon(char *);
68 int	 parse_user_host_path(const char *, char **, char **, char **);
69 int	 parse_user_host_port(const char *, char **, char **, int *);
70 int	 parse_uri(const char *, const char *, char **, char **, int *, char **);
71 int	 convtime(const char *);
72 const char *fmt_timeframe(time_t t);
73 char	*tilde_expand_filename(const char *, uid_t);
74 
75 char	*dollar_expand(int *, const char *string, ...);
76 char	*percent_expand(const char *, ...) __attribute__((__sentinel__));
77 char	*percent_dollar_expand(const char *, ...) __attribute__((__sentinel__));
78 char	*tohex(const void *, size_t);
79 void	 xextendf(char **s, const char *sep, const char *fmt, ...)
80     __attribute__((__format__ (printf, 3, 4))) __attribute__((__nonnull__ (3)));
81 void	 sanitise_stdfd(void);
82 void	 ms_subtract_diff(struct timeval *, int *);
83 void	 ms_to_timeval(struct timeval *, int);
84 void	 monotime_ts(struct timespec *);
85 void	 monotime_tv(struct timeval *);
86 time_t	 monotime(void);
87 double	 monotime_double(void);
88 void	 lowercase(char *s);
89 int	 unix_listener(const char *, int, int);
90 int	 valid_domain(char *, int, const char **);
91 int	 valid_env_name(const char *);
92 const char *atoi_err(const char *, int *);
93 int	 parse_absolute_time(const char *, uint64_t *);
94 void	 format_absolute_time(uint64_t, char *, size_t);
95 int	 path_absolute(const char *);
96 int	 stdfd_devnull(int, int, int);
97 
98 void	 sock_set_v6only(int);
99 
100 struct passwd *pwcopy(struct passwd *);
101 const char *ssh_gai_strerror(int);
102 
103 typedef void privdrop_fn(struct passwd *);
104 typedef void privrestore_fn(void);
105 #define	SSH_SUBPROCESS_STDOUT_DISCARD	(1)     /* Discard stdout */
106 #define	SSH_SUBPROCESS_STDOUT_CAPTURE	(1<<1)  /* Redirect stdout */
107 #define	SSH_SUBPROCESS_STDERR_DISCARD	(1<<2)  /* Discard stderr */
108 #define	SSH_SUBPROCESS_UNSAFE_PATH	(1<<3)	/* Don't check for safe cmd */
109 #define	SSH_SUBPROCESS_PRESERVE_ENV	(1<<4)	/* Keep parent environment */
110 pid_t subprocess(const char *, const char *, int, char **, FILE **, u_int,
111     struct passwd *, privdrop_fn *, privrestore_fn *);
112 
113 typedef struct arglist arglist;
114 struct arglist {
115 	char    **list;
116 	u_int   num;
117 	u_int   nalloc;
118 };
119 void	 addargs(arglist *, char *, ...)
120 	    __attribute__((format(printf, 2, 3)));
121 void	 replacearg(arglist *, u_int, char *, ...)
122 	    __attribute__((format(printf, 3, 4)));
123 void	 freeargs(arglist *);
124 
125 int	 tun_open(int, int, char **);
126 
127 /* Common definitions for ssh tunnel device forwarding */
128 #define SSH_TUNMODE_NO		0x00
129 #define SSH_TUNMODE_POINTOPOINT	0x01
130 #define SSH_TUNMODE_ETHERNET	0x02
131 #define SSH_TUNMODE_DEFAULT	SSH_TUNMODE_POINTOPOINT
132 #define SSH_TUNMODE_YES		(SSH_TUNMODE_POINTOPOINT|SSH_TUNMODE_ETHERNET)
133 
134 #define SSH_TUNID_ANY		0x7fffffff
135 #define SSH_TUNID_ERR		(SSH_TUNID_ANY - 1)
136 #define SSH_TUNID_MAX		(SSH_TUNID_ANY - 2)
137 
138 /* Fake port to indicate that host field is really a path. */
139 #define PORT_STREAMLOCAL	-2
140 
141 /* Functions to extract or store big-endian words of various sizes */
142 u_int64_t	get_u64(const void *)
143     __attribute__((__bounded__( __minbytes__, 1, 8)));
144 u_int32_t	get_u32(const void *)
145     __attribute__((__bounded__( __minbytes__, 1, 4)));
146 u_int16_t	get_u16(const void *)
147     __attribute__((__bounded__( __minbytes__, 1, 2)));
148 void		put_u64(void *, u_int64_t)
149     __attribute__((__bounded__( __minbytes__, 1, 8)));
150 void		put_u32(void *, u_int32_t)
151     __attribute__((__bounded__( __minbytes__, 1, 4)));
152 void		put_u16(void *, u_int16_t)
153     __attribute__((__bounded__( __minbytes__, 1, 2)));
154 
155 /* Little-endian store/load, used by umac.c */
156 u_int32_t	get_u32_le(const void *)
157     __attribute__((__bounded__(__minbytes__, 1, 4)));
158 void		put_u32_le(void *, u_int32_t)
159     __attribute__((__bounded__(__minbytes__, 1, 4)));
160 
161 struct bwlimit {
162 	size_t buflen;
163 	u_int64_t rate;		/* desired rate in kbit/s */
164 	u_int64_t thresh;	/* threshold after which we'll check timers */
165 	u_int64_t lamt;		/* amount written in last timer interval */
166 	struct timeval bwstart, bwend;
167 };
168 
169 void bandwidth_limit_init(struct bwlimit *, u_int64_t, size_t);
170 void bandwidth_limit(struct bwlimit *, size_t);
171 
172 int parse_ipqos(const char *);
173 const char *iptos2str(int);
174 void mktemp_proto(char *, size_t);
175 
176 void	 child_set_env(char ***envp, u_int *envsizep, const char *name,
177 	    const char *value);
178 
179 int	 argv_split(const char *, int *, char ***);
180 char	*argv_assemble(int, char **argv);
181 int	 exited_cleanly(pid_t, const char *, const char *, int);
182 
183 struct stat;
184 int	 safe_path(const char *, struct stat *, const char *, uid_t,
185 	    char *, size_t);
186 int	 safe_path_fd(int, const char *, struct passwd *,
187 	    char *err, size_t errlen);
188 
189 /* authorized_key-style options parsing helpers */
190 int	opt_flag(const char *opt, int allow_negate, const char **optsp);
191 char	*opt_dequote(const char **sp, const char **errstrp);
192 int	opt_match(const char **opts, const char *term);
193 
194 /* readconf/servconf option lists */
195 void	opt_array_append(const char *file, const int line,
196 	    const char *directive, char ***array, u_int *lp, const char *s);
197 void	opt_array_append2(const char *file, const int line,
198 	    const char *directive, char ***array, int **iarray, u_int *lp,
199 	    const char *s, int i);
200 
201 /* readpass.c */
202 
203 #define RP_ECHO			0x0001
204 #define RP_ALLOW_STDIN		0x0002
205 #define RP_ALLOW_EOF		0x0004
206 #define RP_USE_ASKPASS		0x0008
207 
208 struct notifier_ctx;
209 
210 char	*read_passphrase(const char *, int);
211 int	 ask_permission(const char *, ...) __attribute__((format(printf, 1, 2)));
212 struct notifier_ctx *notify_start(int, const char *, ...)
213 	__attribute__((format(printf, 2, 3)));
214 void	notify_complete(struct notifier_ctx *, const char *, ...)
215 	__attribute__((format(printf, 2, 3)));
216 
217 #define MINIMUM(a, b)	(((a) < (b)) ? (a) : (b))
218 #define MAXIMUM(a, b)	(((a) > (b)) ? (a) : (b))
219 #define ROUNDUP(x, y)   ((((x)+((y)-1))/(y))*(y))
220 
221 typedef void (*sshsig_t)(int);
222 sshsig_t ssh_signal(int, sshsig_t);
223 
224 #endif /* _MISC_H */
225