xref: /dragonfly/crypto/openssh/hostfile.h (revision 50a69bb51183a7916e776f2c9f5fa64c999f1a2f)
1 /* $OpenBSD: hostfile.h,v 1.29 2021/01/26 00:51:30 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 #ifndef HOSTFILE_H
15 #define HOSTFILE_H
16 
17 typedef enum {
18           HOST_OK, HOST_NEW, HOST_CHANGED, HOST_REVOKED, HOST_FOUND
19 }       HostStatus;
20 
21 typedef enum {
22           MRK_ERROR, MRK_NONE, MRK_REVOKE, MRK_CA
23 }         HostkeyMarker;
24 
25 struct hostkey_entry {
26           char *host;
27           char *file;
28           u_long line;
29           struct sshkey *key;
30           HostkeyMarker marker;
31           u_int note; /* caller-specific note/flag */
32 };
33 struct hostkeys {
34           struct hostkey_entry *entries;
35           u_int num_entries;
36 };
37 
38 struct hostkeys *init_hostkeys(void);
39 void       load_hostkeys(struct hostkeys *, const char *,
40     const char *, u_int);
41 void       load_hostkeys_file(struct hostkeys *, const char *,
42     const char *, FILE *, u_int note);
43 void       free_hostkeys(struct hostkeys *);
44 
45 HostStatus check_key_in_hostkeys(struct hostkeys *, struct sshkey *,
46     const struct hostkey_entry **);
47 int        lookup_key_in_hostkeys_by_type(struct hostkeys *, int, int,
48     const struct hostkey_entry **);
49 int        lookup_marker_in_hostkeys(struct hostkeys *, int);
50 
51 int        hostfile_read_key(char **, u_int *, struct sshkey *);
52 int        add_host_to_hostfile(const char *, const char *,
53     const struct sshkey *, int);
54 
55 int        hostfile_replace_entries(const char *filename,
56     const char *host, const char *ip, struct sshkey **keys, size_t nkeys,
57     int store_hash, int quiet, int hash_alg);
58 
59 #define HASH_MAGIC  "|1|"
60 #define HASH_DELIM  '|'
61 
62 #define CA_MARKER   "@cert-authority"
63 #define REVOKE_MARKER         "@revoked"
64 
65 char      *host_hash(const char *, const char *, u_int);
66 
67 /*
68  * Iterate through a hostkeys file, optionally parsing keys and matching
69  * hostnames. Allows access to the raw keyfile lines to allow
70  * streaming edits to the file to take place.
71  */
72 #define HKF_WANT_MATCH                  (1)       /* return only matching hosts/addrs */
73 #define HKF_WANT_PARSE_KEY    (1<<1)    /* need key parsed */
74 
75 #define HKF_STATUS_OK                   0         /* Line parsed, didn't match host */
76 #define HKF_STATUS_INVALID    1         /* line had parse error */
77 #define HKF_STATUS_COMMENT    2         /* valid line contained no key */
78 #define HKF_STATUS_MATCHED    3         /* hostname or IP matched */
79 
80 #define HKF_MATCH_HOST                  (1)       /* hostname matched */
81 #define HKF_MATCH_IP                    (1<<1)    /* address matched */
82 #define HKF_MATCH_HOST_HASHED (1<<2)    /* hostname was hashed */
83 #define HKF_MATCH_IP_HASHED   (1<<3)    /* address was hashed */
84 /* XXX HKF_MATCH_KEY_TYPE? */
85 
86 /*
87  * The callback function receives this as an argument for each matching
88  * hostkey line. The callback may "steal" the 'key' field by setting it to NULL.
89  * If a parse error occurred, then "hosts" and subsequent options may be NULL.
90  */
91 struct hostkey_foreach_line {
92           const char *path; /* Path of file */
93           u_long linenum;     /* Line number */
94           u_int status;       /* One of HKF_STATUS_* */
95           u_int match;        /* Zero or more of HKF_MATCH_* OR'd together */
96           char *line;         /* Entire key line; mutable by callback */
97           int marker;         /* CA/revocation markers; indicated by MRK_* value */
98           const char *hosts; /* Raw hosts text, may be hashed or list multiple */
99           const char *rawkey; /* Text of key and any comment following it */
100           int keytype;        /* Type of key; KEY_UNSPEC for invalid/comment lines */
101           struct sshkey *key; /* Key, if parsed ok and HKF_WANT_MATCH_HOST set */
102           const char *comment; /* Any comment following the key */
103           u_int note;         /* caller-specified note copied from arguments */
104 };
105 
106 /*
107  * Callback fires for each line (or matching line if a HKF_WANT_* option
108  * is set). The foreach loop will terminate if the callback returns a non-
109  * zero exit status.
110  */
111 typedef int hostkeys_foreach_fn(struct hostkey_foreach_line *l, void *ctx);
112 
113 /* Iterate over a hostkeys file */
114 int hostkeys_foreach(const char *path,
115     hostkeys_foreach_fn *callback, void *ctx,
116     const char *host, const char *ip, u_int options, u_int note);
117 int hostkeys_foreach_file(const char *path, FILE *f,
118     hostkeys_foreach_fn *callback, void *ctx,
119     const char *host, const char *ip, u_int options, u_int note);
120 
121 void hostfile_create_user_ssh_dir(const char *, int);
122 
123 #endif
124