1 files changed, 548 insertions, 0 deletions

diff --git a/src/bounce/bounce_template.c b/src/bounce/bounce_template.c
new file mode 100644
index 0000000..67a5cf7
--- /dev/null
+++ b/src/bounce/bounce_template.c
@@ -0,0 +1,548 @@
+/*++
+/* NAME
+/*	bounce_template 3
+/* SUMMARY
+/*	bounce template support
+/* SYNOPSIS
+/*	#include <bounce_template.h>
+/*
+/*	BOUNCE_TEMPLATE *bounce_template_create(def_template)
+/*	const BOUNCE_TEMPLATE *def_template;
+/*
+/*	void	bounce_template_free(template)
+/*	BOUNCE_TEMPLATE *template;
+/*
+/*	void	bounce_template_load(template, stream, buffer, origin)
+/*	BOUNCE_TEMPLATE *template;
+/*	VSTREAM	*stream;
+/*	const char *buffer;
+/*	const char *origin;
+/*
+/*	void	bounce_template_headers(out_fn, stream, template,
+/*					rcpt, postmaster_copy)
+/*	int	(*out_fn)(VSTREAM *, const char *, ...);
+/*	VSTREAM	*stream;
+/*	BOUNCE_TEMPLATE *template;
+/*	const char *rcpt;
+/*	int	postmaster_copy;
+/*
+/*	const char *bounce_template_encoding(template)
+/*	BOUNCE_TEMPLATE *template;
+/*
+/*	const char *bounce_template_charset(template)
+/*	BOUNCE_TEMPLATE *template;
+/*
+/*	void	bounce_template_expand(out_fn, stream, template)
+/*	int	(*out_fn)(VSTREAM *, const char *);
+/*	VSTREAM	*stream;
+/*	BOUNCE_TEMPLATE *template;
+/*
+/*	void	bounce_template_dump(stream, template)
+/*	VSTREAM	*stream;
+/*	BOUNCE_TEMPLATE *template;
+/*
+/*	int	IS_FAILURE_TEMPLATE(template)
+/*	int	IS_DELAY_TEMPLATE(template)
+/*	int	IS_SUCCESS_TEMPLATE(template)
+/*	BOUNCE_TEMPLATE *template;
+/* DESCRIPTION
+/*	This module implements the built-in and external bounce
+/*	message template support. The content of a template are
+/*	private. To access information within a template, use
+/*	the API described in this document.
+/*
+/*	bounce_template_create() creates a template, with the
+/*	specified default settings. The template defaults are not
+/*	copied.
+/*
+/*	bounce_template_free() destroys a bounce message template.
+/*
+/*	bounce_template_load() overrides a bounce template with the
+/*	specified buffer from the specified origin. The buffer and
+/*	origin are copied. Specify a null buffer and origin pointer
+/*	to reset the template to the defaults specified with
+/*	bounce_template_create().
+/*
+/*	bounce_template_headers() sends the postmaster or non-postmaster
+/*	From/Subject/To message headers to the specified stream.
+/*	The recipient address is expected to be in RFC822 external
+/*	form. The postmaster_copy argument is one of POSTMASTER_COPY
+/*	or NO_POSTMASTER_COPY.
+/*
+/*	bounce_template_encoding() returns the encoding (MAIL_ATTR_ENC_7BIT
+/*	or MAIL_ATTR_ENC_8BIT) for the bounce template message text.
+/*
+/*	bounce_template_charset() returns the character set for the
+/*	bounce template message text.
+/*
+/*	bounce_template_expand() expands the body text of the
+/*	specified template and writes the result to the specified
+/*	stream.
+/*
+/*	bounce_template_dump() dumps the specified template to the
+/*	specified stream.
+/*
+/*	The IS_MUMBLE_TEMPLATE() macros are predicates that
+/*	determine whether the template is of the specified type.
+/* DIAGNOSTICS
+/*	Fatal error: out of memory, undefined macro name in template.
+/* SEE ALSO
+/*	bounce_templates(3) bounce template group support
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*
+/*	Wietse Venema
+/*	Google, Inc.
+/*	111 8th Avenue
+/*	New York, NY 10011, USA
+/*--*/
+
+/* System library. */
+
+#include <sys_defs.h>
+#include <string.h>
+#include <ctype.h>
+
+#ifdef STRCASECMP_IN_STRINGS_H
+#include <strings.h>
+#endif
+
+/* Utility library. */
+
+#include <msg.h>
+#include <mac_expand.h>
+#include <split_at.h>
+#include <stringops.h>
+#include <mymalloc.h>
+#ifndef NO_EAI
+#include <midna_domain.h>
+#endif
+
+/* Global library. */
+
+#include <mail_params.h>
+#include <mail_proto.h>
+#include <mail_conf.h>
+#include <is_header.h>
+#include <hfrom_format.h>
+
+/* Application-specific. */
+
+#include <bounce_template.h>
+#include <bounce_service.h>
+
+ /*
+  * The following tables implement support for bounce template expansions of
+  * $<parameter_name>_days ($<parameter_name>_hours, etc.). The expansion of
+  * these is the actual parameter value divided by the number of seconds in a
+  * day (hour, etc.), so that we can produce nicely formatted bounce messages
+  * with time values converted into the appropriate units.
+  * 
+  * Ideally, the bounce template processor would strip the _days etc. suffix
+  * from the parameter name, and use the parameter name to look up the actual
+  * parameter value and its default value (the default value specifies the
+  * default time unit of that parameter (seconds, minutes, etc.)), and use
+  * this to convert the parameter string value into the corresponding number
+  * of seconds. The bounce template processor would then use the _hours etc.
+  * suffix from the bounce template to divide this number by the number of
+  * seconds in an hour, etc. and produce the number that is needed for the
+  * template.
+  * 
+  * Unfortunately, there exists no code to look up default values by parameter
+  * name. If such code existed, then we could do the _days, _hours, etc.
+  * conversion with every main.cf time parameter without having to know in
+  * advance what time parameter names exist.
+  * 
+  * So we have to either maintain our own table of all time related main.cf
+  * parameter names and defaults (like the postconf command does) or we make
+  * a special case for a few parameters of special interest.
+  * 
+  * We go for the second solution. There are only a few parameters that need
+  * this treatment, and there will be more special cases when individual
+  * queue files get support for individual expiration times, and when other
+  * queue file information needs to be reported in bounce template messages.
+  * 
+  * A really lame implementation would simply strip the optional s, h, d, etc.
+  * suffix from the actual (string) parameter value and not do any conversion
+  * at all to hours, days or weeks. But then the information in delay warning
+  * notices could be seriously incorrect.
+  */
+typedef struct {
+    const char *suffix;			/* days, hours, etc. */
+    int     suffix_len;			/* byte count */
+    int     divisor;			/* divisor */
+} BOUNCE_TIME_DIVISOR;
+
+#define STRING_AND_LEN(x) (x), (sizeof(x) - 1)
+
+static const BOUNCE_TIME_DIVISOR time_divisors[] = {
+    STRING_AND_LEN("seconds"), 1,
+    STRING_AND_LEN("minutes"), 60,
+    STRING_AND_LEN("hours"), 60 * 60,
+    STRING_AND_LEN("days"), 24 * 60 * 60,
+    STRING_AND_LEN("weeks"), 7 * 24 * 60 * 60,
+    0, 0,
+};
+
+ /*
+  * The few special-case main.cf parameters that have support for _days, etc.
+  * suffixes for automatic conversion when expanded into a bounce template.
+  */
+typedef struct {
+    const char *param_name;		/* parameter name */
+    int     param_name_len;		/* name length */
+    int    *value;			/* parameter value */
+} BOUNCE_TIME_PARAMETER;
+
+static const BOUNCE_TIME_PARAMETER time_parameter[] = {
+    STRING_AND_LEN(VAR_DELAY_WARN_TIME), &var_delay_warn_time,
+    STRING_AND_LEN(VAR_MAX_QUEUE_TIME), &var_max_queue_time,
+    0, 0,
+};
+
+ /*
+  * Parameters whose value may have to be converted to UTF-8 for presentation
+  * purposes.
+  */
+typedef struct {
+    const char *param_name;		/* parameter name */
+    char  **value;			/* parameter value */
+} BOUNCE_STR_PARAMETER;
+
+static const BOUNCE_STR_PARAMETER str_parameter[] = {
+    VAR_MYHOSTNAME, &var_myhostname,
+    VAR_MYDOMAIN, &var_mydomain,
+    0, 0,
+};
+
+ /*
+  * SLMs.
+  */
+#define STR(x) vstring_str(x)
+
+/* bounce_template_create - create one template */
+
+BOUNCE_TEMPLATE *bounce_template_create(const BOUNCE_TEMPLATE *prototype)
+{
+    BOUNCE_TEMPLATE *tp;
+
+    tp = (BOUNCE_TEMPLATE *) mymalloc(sizeof(*tp));
+    *tp = *prototype;
+    return (tp);
+}
+
+/* bounce_template_free - destroy one template */
+
+void    bounce_template_free(BOUNCE_TEMPLATE *tp)
+{
+    if (tp->buffer) {
+	myfree(tp->buffer);
+	myfree((void *) tp->origin);
+    }
+    myfree((void *) tp);
+}
+
+/* bounce_template_reset - reset template to default */
+
+static void bounce_template_reset(BOUNCE_TEMPLATE *tp)
+{
+    myfree(tp->buffer);
+    myfree((void *) tp->origin);
+    *tp = *(tp->prototype);
+}
+
+/* bounce_template_load - override one template */
+
+void    bounce_template_load(BOUNCE_TEMPLATE *tp, const char *origin,
+			             const char *buffer)
+{
+
+    /*
+     * Clean up after a previous call.
+     */
+    if (tp->buffer)
+	bounce_template_reset(tp);
+
+    /*
+     * Postpone the work of template parsing until it is really needed. Most
+     * bounce service calls never need a template.
+     */
+    if (buffer && origin) {
+	tp->flags |= BOUNCE_TMPL_FLAG_NEW_BUFFER;
+	tp->buffer = mystrdup(buffer);
+	tp->origin = mystrdup(origin);
+    }
+}
+
+/* bounce_template_parse_buffer - initialize template */
+
+static void bounce_template_parse_buffer(BOUNCE_TEMPLATE *tp)
+{
+    char   *tval = tp->buffer;
+    char   *cp;
+    char  **cpp;
+    int     cpp_len;
+    int     cpp_used;
+    int     hlen;
+    char   *hval;
+
+    /*
+     * Sanity check.
+     */
+    if ((tp->flags & BOUNCE_TMPL_FLAG_NEW_BUFFER) == 0)
+	msg_panic("bounce_template_parse_buffer: nothing to do here");
+    tp->flags &= ~BOUNCE_TMPL_FLAG_NEW_BUFFER;
+
+    /*
+     * Discard the unusable template and use the default one instead.
+     */
+#define CLEANUP_AND_RETURN() do { \
+	bounce_template_reset(tp); \
+	return; \
+    } while (0)
+
+    /*
+     * Parse pseudo-header labels and values.
+     * 
+     * XXX EAI: allow UTF8 in template headers when responding to SMTPUTF8
+     * message. Sending SMTPUTF8 in response to non-SMTPUTF8 mail would make
+     * no sense.
+     */
+#define GETLINE(line, buf) \
+        (((line) = (buf)) != 0 ? ((buf) = split_at((buf), '\n'), (line)) : 0)
+
+    while ((GETLINE(cp, tval)) != 0 && (hlen = is_header(cp)) > 0) {
+	for (hval = cp + hlen; *hval && (*hval == ':' || ISSPACE(*hval)); hval++)
+	    *hval = 0;
+	if (*hval == 0) {
+	    msg_warn("%s: empty \"%s\" header value in %s template "
+		     "-- ignoring this template",
+		     tp->origin, cp, tp->class);
+	    CLEANUP_AND_RETURN();
+	}
+	if (!allascii(hval)) {
+	    msg_warn("%s: non-ASCII \"%s\" header value in %s template "
+		     "-- ignoring this template",
+		     tp->origin, cp, tp->class);
+	    CLEANUP_AND_RETURN();
+	}
+	if (strcasecmp("charset", cp) == 0) {
+	    tp->mime_charset = hval;
+	} else if (strcasecmp("from", cp) == 0) {
+	    tp->std_from = tp->obs_from = hval;
+	} else if (strcasecmp("subject", cp) == 0) {
+	    tp->subject = hval;
+	} else if (strcasecmp("postmaster-subject", cp) == 0) {
+	    if (tp->postmaster_subject == 0) {
+		msg_warn("%s: inapplicable \"%s\" header label in %s template "
+			 "-- ignoring this template",
+			 tp->origin, cp, tp->class);
+		CLEANUP_AND_RETURN();
+	    }
+	    tp->postmaster_subject = hval;
+	} else {
+	    msg_warn("%s: unknown \"%s\" header label in %s template "
+		     "-- ignoring this template",
+		     tp->origin, cp, tp->class);
+	    CLEANUP_AND_RETURN();
+	}
+    }
+
+    /*
+     * Skip blank lines between header and message text.
+     */
+    while (cp && (*cp == 0 || allspace(cp)))
+	(void) GETLINE(cp, tval);
+    if (cp == 0) {
+	msg_warn("%s: missing message text in %s template "
+		 "-- ignoring this template",
+		 tp->origin, tp->class);
+	CLEANUP_AND_RETURN();
+    }
+
+    /*
+     * Is this 7bit or 8bit text? If the character set is US-ASCII, then
+     * don't allow 8bit text. Don't assume 8bit when charset was changed.
+     */
+#define NON_ASCII(p) ((p) && *(p) && !allascii((p)))
+
+    if (NON_ASCII(cp) || NON_ASCII(tval)) {
+	if (strcasecmp(tp->mime_charset, "us-ascii") == 0) {
+	    msg_warn("%s: 8-bit message text in %s template",
+		     tp->origin, tp->class);
+	    msg_warn("please specify a charset value other than us-ascii");
+	    msg_warn("-- ignoring this template for now");
+	    CLEANUP_AND_RETURN();
+	}
+	tp->mime_encoding = MAIL_ATTR_ENC_8BIT;
+    }
+
+    /*
+     * Collect the message text and null-terminate the result.
+     */
+    cpp_len = 10;
+    cpp_used = 0;
+    cpp = (char **) mymalloc(sizeof(*cpp) * cpp_len);
+    while (cp) {
+	cpp[cpp_used++] = cp;
+	if (cpp_used >= cpp_len) {
+	    cpp = (char **) myrealloc((void *) cpp,
+				      sizeof(*cpp) * 2 * cpp_len);
+	    cpp_len *= 2;
+	}
+	(void) GETLINE(cp, tval);
+    }
+    cpp[cpp_used] = 0;
+    tp->message_text = (const char **) cpp;
+}
+
+/* bounce_template_lookup - lookup $name value */
+
+static const char *bounce_template_lookup(const char *key, int unused_mode,
+					          void *context)
+{
+    BOUNCE_TEMPLATE *tp = (BOUNCE_TEMPLATE *) context;
+    const BOUNCE_TIME_PARAMETER *bp;
+    const BOUNCE_TIME_DIVISOR *bd;
+    const BOUNCE_STR_PARAMETER *sp;
+    static VSTRING *buf;
+    int     result;
+    const char *asc_val;
+    const char *utf8_val;
+
+    /*
+     * Look for parameter names that can have a time unit suffix, and scale
+     * the time value according to the suffix.
+     */
+    for (bp = time_parameter; bp->param_name; bp++) {
+	if (strncmp(key, bp->param_name, bp->param_name_len) == 0
+	    && key[bp->param_name_len] == '_') {
+	    for (bd = time_divisors; bd->suffix; bd++) {
+		if (strcmp(key + bp->param_name_len + 1, bd->suffix) == 0) {
+		    result = bp->value[0] / bd->divisor;
+		    if (result > 999 && bd->divisor < 86400) {
+			msg_warn("%s: excessive result \"%d\" in %s "
+				 "template conversion of parameter \"%s\"",
+				 tp->origin, result, tp->class, key);
+			msg_warn("please increase time unit \"%s\" of \"%s\" "
+			      "in %s template", bd->suffix, key, tp->class);
+			msg_warn("for instructions see the bounce(5) manual");
+		    } else if (result == 0 && bp->value[0] && bd->divisor > 1) {
+			msg_warn("%s: zero result in %s template "
+				 "conversion of parameter \"%s\"",
+				 tp->origin, tp->class, key);
+			msg_warn("please reduce time unit \"%s\" of \"%s\" "
+			      "in %s template", bd->suffix, key, tp->class);
+			msg_warn("for instructions see the bounce(5) manual");
+		    }
+		    if (buf == 0)
+			buf = vstring_alloc(10);
+		    vstring_sprintf(buf, "%d", result);
+		    return (STR(buf));
+		}
+	    }
+	    msg_fatal("%s: unrecognized suffix \"%s\" in parameter \"%s\"",
+		      tp->origin,
+		      key + bp->param_name_len + 1, key);
+	}
+    }
+
+    /*
+     * Look for parameter names that may have to be up-converted for
+     * presentation purposes.
+     */
+#ifndef NO_EAI
+    if (var_smtputf8_enable) {
+	for (sp = str_parameter; sp->param_name; sp++) {
+	    if (strcmp(key, sp->param_name) == 0) {
+		asc_val = sp->value[0];
+		if (!allascii(asc_val)) {
+		    msg_warn("%s: conversion \"%s\" failed: "
+			     "non-ASCII input value: \"%s\"",
+			     tp->origin, key, asc_val);
+		    return (asc_val);
+		} else if ((utf8_val = midna_domain_to_utf8(asc_val)) == 0) {
+		    msg_warn("%s: conversion \"%s\" failed: "
+			     "input value: \"%s\"",
+			     tp->origin, key, asc_val);
+		    return (asc_val);
+		} else {
+		    return (utf8_val);
+		}
+	    }
+	}
+    }
+#endif
+    return (mail_conf_lookup_eval(key));
+}
+
+/* bounce_template_headers - send template headers */
+
+void    bounce_template_headers(BOUNCE_XP_PRN_FN out_fn, VSTREAM *fp,
+				        BOUNCE_TEMPLATE *tp,
+				        const char *rcpt,
+				        int postmaster_copy)
+{
+    if (tp->flags & BOUNCE_TMPL_FLAG_NEW_BUFFER)
+	bounce_template_parse_buffer(tp);
+
+    out_fn(fp, "From: %s", bounce_hfrom_format == HFROM_FORMAT_CODE_STD ?
+	   tp->std_from : tp->obs_from);
+    out_fn(fp, "Subject: %s", tp->postmaster_subject && postmaster_copy ?
+	   tp->postmaster_subject : tp->subject);
+    out_fn(fp, "To: %s", rcpt);
+}
+
+/* bounce_template_expand - expand template to stream */
+
+void    bounce_template_expand(BOUNCE_XP_PUT_FN out_fn, VSTREAM *fp,
+			               BOUNCE_TEMPLATE *tp)
+{
+    VSTRING *buf = vstring_alloc(100);
+    const char **cpp;
+    int     stat;
+
+    if (tp->flags & BOUNCE_TMPL_FLAG_NEW_BUFFER)
+	bounce_template_parse_buffer(tp);
+
+    for (cpp = tp->message_text; *cpp; cpp++) {
+	stat = mac_expand(buf, *cpp, MAC_EXP_FLAG_PRINTABLE, (char *) 0,
+			  bounce_template_lookup, (void *) tp);
+	if (stat & MAC_PARSE_ERROR)
+	    msg_fatal("%s: bad $name syntax in %s template: %s",
+		      tp->origin, tp->class, *cpp);
+	if (stat & MAC_PARSE_UNDEF)
+	    msg_fatal("%s: undefined $name in %s template: %s",
+		      tp->origin, tp->class, *cpp);
+	out_fn(fp, STR(buf));
+    }
+    vstring_free(buf);
+}
+
+/* bounce_template_dump - dump template to stream */
+
+void    bounce_template_dump(VSTREAM *fp, BOUNCE_TEMPLATE *tp)
+{
+    const char **cpp;
+
+    if (tp->flags & BOUNCE_TMPL_FLAG_NEW_BUFFER)
+	bounce_template_parse_buffer(tp);
+
+    vstream_fprintf(fp, "Charset: %s\n", tp->mime_charset);
+    vstream_fprintf(fp, "From: %s\n", bounce_hfrom_format == HFROM_FORMAT_CODE_STD ?
+		    tp->std_from : tp->obs_from);
+    vstream_fprintf(fp, "Subject: %s\n", tp->subject);
+    if (tp->postmaster_subject)
+	vstream_fprintf(fp, "Postmaster-Subject: %s\n",
+			tp->postmaster_subject);
+    vstream_fprintf(fp, "\n");
+    for (cpp = tp->message_text; *cpp; cpp++)
+	vstream_fprintf(fp, "%s\n", *cpp);
+}