1 #ifndef _MILTER_H_INCLUDED_
2 #define _MILTER_H_INCLUDED_
3 
4 /*++
5 /* NAME
6 /*	milter 3h
7 /* SUMMARY
8 /*	smtp server
9 /* SYNOPSIS
10 /*	Postfix MTA-side Milter implementation
11 /* DESCRIPTION
12 /* .nf
13 
14  /*
15   * Utility library.
16   */
17 #include <vstring.h>
18 #include <vstream.h>
19 #include <argv.h>
20 
21  /*
22   * Global library.
23   */
24 #include <attr.h>
25 
26  /*
27   * Each Milter handle is an element of a null-terminated linked list. The
28   * functions are virtual so that we can support multiple MTA-side Milter
29   * implementations. The Sendmail 8 and Sendmail X Milter-side APIs are too
30   * different to implement the MTA side as a single hybrid.
31   */
32 typedef struct MILTER {
33     char   *name;			/* full name including transport */
34     int     flags;			/* see below */
35     struct MILTER *next;		/* linkage */
36     struct MILTERS *parent;		/* parent information */
37     struct MILTER_MACROS *macros;	/* private macros */
38     void    (*connect_on_demand) (struct MILTER *);
39     const char *(*conn_event) (struct MILTER *, const char *, const char *, const char *, unsigned, ARGV *);
40     const char *(*helo_event) (struct MILTER *, const char *, int, ARGV *);
41     const char *(*mail_event) (struct MILTER *, const char **, ARGV *);
42     const char *(*rcpt_event) (struct MILTER *, const char **, ARGV *);
43     const char *(*data_event) (struct MILTER *, ARGV *);
44     const char *(*message) (struct MILTER *, VSTREAM *, off_t, ARGV *, ARGV *, ARGV *);
45     const char *(*unknown_event) (struct MILTER *, const char *, ARGV *);
46     const char *(*other_event) (struct MILTER *);
47     void    (*abort) (struct MILTER *);
48     void    (*disc_event) (struct MILTER *);
49     int     (*active) (struct MILTER *);
50     int     (*send) (struct MILTER *, VSTREAM *);
51     void    (*free) (struct MILTER *);
52 } MILTER;
53 
54 #define MILTER_FLAG_NONE		(0)
55 #define MILTER_FLAG_WANT_RCPT_REJ	(1<<0)	/* see S8_RCPT_MAILER_ERROR */
56 
57 extern MILTER *milter8_create(const char *, int, int, int, const char *, const char *, struct MILTERS *);
58 extern MILTER *milter8_receive(VSTREAM *, struct MILTERS *);
59 
60  /*
61   * As of Sendmail 8.14 each milter can override the default macro list. If a
62   * Milter has its own macro list, a null member means use the global
63   * definition.
64   */
65 typedef struct MILTER_MACROS {
66     char   *conn_macros;		/* macros for connect event */
67     char   *helo_macros;		/* macros for HELO/EHLO command */
68     char   *mail_macros;		/* macros for MAIL FROM command */
69     char   *rcpt_macros;		/* macros for RCPT TO command */
70     char   *data_macros;		/* macros for DATA command */
71     char   *eoh_macros;			/* macros for end-of-headers */
72     char   *eod_macros;			/* macros for END-OF-DATA command */
73     char   *unk_macros;			/* macros for unknown command */
74 } MILTER_MACROS;
75 
76 extern MILTER_MACROS *milter_macros_create(const char *, const char *,
77 					         const char *, const char *,
78 					         const char *, const char *,
79 					        const char *, const char *);
80 extern MILTER_MACROS *milter_macros_alloc(int);
81 extern void milter_macros_free(MILTER_MACROS *);
82 extern int milter_macros_print(ATTR_PRINT_COMMON_FN, VSTREAM *, int, const void *);
83 extern int milter_macros_scan(ATTR_SCAN_COMMON_FN, VSTREAM *, int, void *);
84 
85 #define MILTER_MACROS_ALLOC_ZERO	1	/* null pointer */
86 #define MILTER_MACROS_ALLOC_EMPTY	2	/* mystrdup(""); */
87 
88  /*
89   * Helper to parse list of name=value default macro settings.
90   */
91 extern struct HTABLE *milter_macro_defaults_create(const char *);
92 
93  /*
94   * A bunch of Milters.
95   */
96 typedef const char *(*MILTER_MAC_LOOKUP_FN) (const char *, void *);
97 typedef const char *(*MILTER_ADD_HEADER_FN) (void *, const char *, const char *, const char *);
98 typedef const char *(*MILTER_EDIT_HEADER_FN) (void *, ssize_t, const char *, const char *, const char *);
99 typedef const char *(*MILTER_DEL_HEADER_FN) (void *, ssize_t, const char *);
100 typedef const char *(*MILTER_EDIT_FROM_FN) (void *, const char *, const char *);
101 typedef const char *(*MILTER_EDIT_RCPT_FN) (void *, const char *);
102 typedef const char *(*MILTER_EDIT_RCPT_PAR_FN) (void *, const char *, const char *);
103 typedef const char *(*MILTER_EDIT_BODY_FN) (void *, int, int, VSTRING *);
104 
105 typedef struct MILTERS {
106     MILTER *milter_list;		/* linked list of Milters */
107     MILTER_MAC_LOOKUP_FN mac_lookup;
108     void   *mac_context;		/* macro lookup context */
109     struct MILTER_MACROS *macros;
110     struct HTABLE *macro_defaults;
111     void   *chg_context;		/* context for queue file changes */
112     MILTER_ADD_HEADER_FN add_header;
113     MILTER_EDIT_HEADER_FN upd_header;
114     MILTER_DEL_HEADER_FN del_header;
115     MILTER_EDIT_HEADER_FN ins_header;
116     MILTER_EDIT_FROM_FN chg_from;
117     MILTER_EDIT_RCPT_FN add_rcpt;
118     MILTER_EDIT_RCPT_PAR_FN add_rcpt_par;
119     MILTER_EDIT_RCPT_FN del_rcpt;
120     MILTER_EDIT_BODY_FN repl_body;
121 } MILTERS;
122 
123 #define milter_create(milter_names, conn_timeout, cmd_timeout, msg_timeout, \
124 			protocol, def_action, conn_macros, helo_macros, \
125 			mail_macros, rcpt_macros, data_macros, eoh_macros, \
126 			eod_macros, unk_macros, macro_deflts) \
127 	milter_new(milter_names, conn_timeout, cmd_timeout, msg_timeout, \
128 		    protocol, def_action, milter_macros_create(conn_macros, \
129 		    helo_macros, mail_macros, rcpt_macros, data_macros, \
130 		    eoh_macros, eod_macros, unk_macros), \
131 		    milter_macro_defaults_create(macro_deflts))
132 
133 extern MILTERS *milter_new(const char *, int, int, int, const char *,
134 			           const char *, MILTER_MACROS *,
135 			           struct HTABLE *);
136 extern void milter_macro_callback(MILTERS *, MILTER_MAC_LOOKUP_FN, void *);
137 extern void milter_edit_callback(MILTERS *milters, MILTER_ADD_HEADER_FN,
138 		               MILTER_EDIT_HEADER_FN, MILTER_EDIT_HEADER_FN,
139 			          MILTER_DEL_HEADER_FN, MILTER_EDIT_FROM_FN,
140 		               MILTER_EDIT_RCPT_FN, MILTER_EDIT_RCPT_PAR_FN,
141 			           MILTER_EDIT_RCPT_FN, MILTER_EDIT_BODY_FN,
142 				         void *);
143 extern const char *milter_conn_event(MILTERS *, const char *, const char *, const char *, unsigned);
144 extern const char *milter_helo_event(MILTERS *, const char *, int);
145 extern const char *milter_mail_event(MILTERS *, const char **);
146 extern const char *milter_rcpt_event(MILTERS *, int, const char **);
147 extern const char *milter_data_event(MILTERS *);
148 extern const char *milter_message(MILTERS *, VSTREAM *, off_t, ARGV *);
149 extern const char *milter_unknown_event(MILTERS *, const char *);
150 extern const char *milter_other_event(MILTERS *);
151 extern void milter_abort(MILTERS *);
152 extern void milter_disc_event(MILTERS *);
153 extern int milter_dummy(MILTERS *, VSTREAM *);
154 extern int milter_send(MILTERS *, VSTREAM *);
155 extern MILTERS *milter_receive(VSTREAM *, int);
156 extern void milter_free(MILTERS *);
157 
158  /*
159   * Milter body edit commands.
160   */
161 #define MILTER_BODY_START	1	/* start message body */
162 #define MILTER_BODY_LINE	2	/* message body line */
163 #define MILTER_BODY_END		3	/* end message body */
164 
165  /*
166   * Sendmail 8 macro names. We support forms with and without the {}.
167   */
168 #define S8_MAC__		"{_}"	/* sender host, see client_resolve */
169 #define S8_MAC_J		"{j}"	/* myhostname */
170 #define S8_MAC_V		"{v}"	/* mail_name + mail_version */
171 
172 #define S8_MAC_DAEMON_NAME	"{daemon_name}"
173 #define S8_MAC_IF_NAME		"{if_name}"
174 #define S8_MAC_IF_ADDR		"{if_addr}"
175 
176 #define S8_MAC_CLIENT_ADDR	"{client_addr}"
177 #define S8_MAC_CLIENT_CONN	"{client_connections}"
178 #define S8_MAC_CLIENT_NAME	"{client_name}"
179 #define S8_MAC_CLIENT_PORT	"{client_port}"
180 #define S8_MAC_CLIENT_PTR	"{client_ptr}"
181 #define S8_MAC_CLIENT_RES	"{client_resolve}"
182 
183 #define S8_MAC_DAEMON_ADDR	"{daemon_addr}"
184 #define S8_MAC_DAEMON_PORT	"{daemon_port}"
185 
186 #define S8_MAC_TLS_VERSION	"{tls_version}"
187 #define S8_MAC_CIPHER		"{cipher}"
188 #define S8_MAC_CIPHER_BITS	"{cipher_bits}"
189 #define S8_MAC_CERT_SUBJECT	"{cert_subject}"
190 #define S8_MAC_CERT_ISSUER	"{cert_issuer}"
191 
192 #define S8_MAC_I		"{i}"	/* queue ID */
193 #define S8_MAC_AUTH_TYPE	"{auth_type}"	/* SASL method */
194 #define S8_MAC_AUTH_AUTHEN	"{auth_authen}"	/* SASL username */
195 #define S8_MAC_AUTH_AUTHOR	"{auth_author}"	/* SASL sender */
196 
197 #define S8_MAC_MAIL_MAILER	"{mail_mailer}"	/* sender transport */
198 #define S8_MAC_MAIL_HOST	"{mail_host}"	/* sender nexthop */
199 #define S8_MAC_MAIL_ADDR	"{mail_addr}"	/* sender address */
200 
201 #define S8_MAC_RCPT_MAILER	"{rcpt_mailer}"	/* recip transport */
202 #define S8_MAC_RCPT_HOST	"{rcpt_host}"	/* recip nexthop */
203 #define S8_MAC_RCPT_ADDR	"{rcpt_addr}"	/* recip address */
204 
205 #define S8_RCPT_MAILER_ERROR	"error"	/* see MILTER_FLAG_WANT_RCPT_REJ */
206 
207 /* LICENSE
208 /* .ad
209 /* .fi
210 /*	The Secure Mailer license must be distributed with this software.
211 /* AUTHOR(S)
212 /*	Wietse Venema
213 /*	IBM T.J. Watson Research
214 /*	P.O. Box 704
215 /*	Yorktown Heights, NY 10598, USA
216 /*
217 /*	Wietse Venema
218 /*	Google, Inc.
219 /*	111 8th Avenue
220 /*	New York, NY 10011, USA
221 /*--*/
222 
223 #endif
224