/
acl.c
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/
acl.c
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/*************************************************
* Exim - an Internet mail transport agent *
*************************************************/
/* Copyright (c) University of Cambridge 1995 - 2018 */
/* Copyright (c) The Exim Maintainers 2020 - 2021 */
/* See the file NOTICE for conditions of use and distribution. */
/* Code for handling Access Control Lists (ACLs) */
#include "exim.h"
#ifndef MACRO_PREDEF
/* Default callout timeout */
#define CALLOUT_TIMEOUT_DEFAULT 30
/* Default quota cache TTLs */
#define QUOTA_POS_DEFAULT (5*60)
#define QUOTA_NEG_DEFAULT (60*60)
/* ACL verb codes - keep in step with the table of verbs that follows */
enum { ACL_ACCEPT, ACL_DEFER, ACL_DENY, ACL_DISCARD, ACL_DROP, ACL_REQUIRE,
ACL_WARN };
/* ACL verbs */
static uschar *verbs[] = {
[ACL_ACCEPT] = US"accept",
[ACL_DEFER] = US"defer",
[ACL_DENY] = US"deny",
[ACL_DISCARD] = US"discard",
[ACL_DROP] = US"drop",
[ACL_REQUIRE] = US"require",
[ACL_WARN] = US"warn"
};
/* For each verb, the conditions for which "message" or "log_message" are used
are held as a bitmap. This is to avoid expanding the strings unnecessarily. For
"accept", the FAIL case is used only after "endpass", but that is selected in
the code. */
static int msgcond[] = {
[ACL_ACCEPT] = BIT(OK) | BIT(FAIL) | BIT(FAIL_DROP),
[ACL_DEFER] = BIT(OK),
[ACL_DENY] = BIT(OK),
[ACL_DISCARD] = BIT(OK) | BIT(FAIL) | BIT(FAIL_DROP),
[ACL_DROP] = BIT(OK),
[ACL_REQUIRE] = BIT(FAIL) | BIT(FAIL_DROP),
[ACL_WARN] = BIT(OK)
};
#endif
/* ACL condition and modifier codes - keep in step with the table that
follows.
down. */
enum { ACLC_ACL,
ACLC_ADD_HEADER,
ACLC_AUTHENTICATED,
#ifdef EXPERIMENTAL_BRIGHTMAIL
ACLC_BMI_OPTIN,
#endif
ACLC_CONDITION,
ACLC_CONTINUE,
ACLC_CONTROL,
#ifdef EXPERIMENTAL_DCC
ACLC_DCC,
#endif
#ifdef WITH_CONTENT_SCAN
ACLC_DECODE,
#endif
ACLC_DELAY,
#ifndef DISABLE_DKIM
ACLC_DKIM_SIGNER,
ACLC_DKIM_STATUS,
#endif
#ifdef SUPPORT_DMARC
ACLC_DMARC_STATUS,
#endif
ACLC_DNSLISTS,
ACLC_DOMAINS,
ACLC_ENCRYPTED,
ACLC_ENDPASS,
ACLC_HOSTS,
ACLC_LOCAL_PARTS,
ACLC_LOG_MESSAGE,
ACLC_LOG_REJECT_TARGET,
ACLC_LOGWRITE,
#ifdef WITH_CONTENT_SCAN
ACLC_MALWARE,
#endif
ACLC_MESSAGE,
#ifdef WITH_CONTENT_SCAN
ACLC_MIME_REGEX,
#endif
ACLC_QUEUE,
ACLC_RATELIMIT,
ACLC_RECIPIENTS,
#ifdef WITH_CONTENT_SCAN
ACLC_REGEX,
#endif
ACLC_REMOVE_HEADER,
ACLC_SEEN,
ACLC_SENDER_DOMAINS,
ACLC_SENDERS,
ACLC_SET,
#ifdef WITH_CONTENT_SCAN
ACLC_SPAM,
#endif
#ifdef SUPPORT_SPF
ACLC_SPF,
ACLC_SPF_GUESS,
#endif
ACLC_UDPSEND,
ACLC_VERIFY };
/* ACL conditions/modifiers: "delay", "control", "continue", "endpass",
"message", "log_message", "log_reject_target", "logwrite", "queue" and "set" are
modifiers that look like conditions but always return TRUE. They are used for
their side effects. Do not invent new modifier names that result in one name
being the prefix of another; the binary-search in the list will go wrong. */
typedef struct condition_def {
uschar *name;
/* Flag to indicate the condition/modifier has a string expansion done
at the outer level. In the other cases, expansion already occurs in the
checking functions. */
BOOL expand_at_top:1;
BOOL is_modifier:1;
/* Bit map vector of which conditions and modifiers are not allowed at certain
times. For each condition and modifier, there's a bitmap of dis-allowed times.
For some, it is easier to specify the negation of a small number of allowed
times. */
unsigned forbids;
} condition_def;
static condition_def conditions[] = {
[ACLC_ACL] = { US"acl", FALSE, FALSE, 0 },
[ACLC_ADD_HEADER] = { US"add_header", TRUE, TRUE,
(unsigned int)
~(ACL_BIT_MAIL | ACL_BIT_RCPT |
ACL_BIT_PREDATA | ACL_BIT_DATA |
#ifndef DISABLE_PRDR
ACL_BIT_PRDR |
#endif
ACL_BIT_MIME | ACL_BIT_NOTSMTP |
ACL_BIT_DKIM |
ACL_BIT_NOTSMTP_START),
},
[ACLC_AUTHENTICATED] = { US"authenticated", FALSE, FALSE,
ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START |
ACL_BIT_CONNECT | ACL_BIT_HELO,
},
#ifdef EXPERIMENTAL_BRIGHTMAIL
[ACLC_BMI_OPTIN] = { US"bmi_optin", TRUE, TRUE,
ACL_BIT_AUTH |
ACL_BIT_CONNECT | ACL_BIT_HELO |
ACL_BIT_DATA | ACL_BIT_MIME |
# ifndef DISABLE_PRDR
ACL_BIT_PRDR |
# endif
ACL_BIT_ETRN | ACL_BIT_EXPN |
ACL_BIT_MAILAUTH |
ACL_BIT_MAIL | ACL_BIT_STARTTLS |
ACL_BIT_VRFY | ACL_BIT_PREDATA |
ACL_BIT_NOTSMTP_START,
},
#endif
[ACLC_CONDITION] = { US"condition", TRUE, FALSE, 0 },
[ACLC_CONTINUE] = { US"continue", TRUE, TRUE, 0 },
/* Certain types of control are always allowed, so we let it through
always and check in the control processing itself. */
[ACLC_CONTROL] = { US"control", TRUE, TRUE, 0 },
#ifdef EXPERIMENTAL_DCC
[ACLC_DCC] = { US"dcc", TRUE, FALSE,
(unsigned int)
~(ACL_BIT_DATA |
# ifndef DISABLE_PRDR
ACL_BIT_PRDR |
# endif
ACL_BIT_NOTSMTP),
},
#endif
#ifdef WITH_CONTENT_SCAN
[ACLC_DECODE] = { US"decode", TRUE, FALSE, (unsigned int) ~ACL_BIT_MIME },
#endif
[ACLC_DELAY] = { US"delay", TRUE, TRUE, ACL_BIT_NOTQUIT },
#ifndef DISABLE_DKIM
[ACLC_DKIM_SIGNER] = { US"dkim_signers", TRUE, FALSE, (unsigned int) ~ACL_BIT_DKIM },
[ACLC_DKIM_STATUS] = { US"dkim_status", TRUE, FALSE, (unsigned int) ~ACL_BIT_DKIM },
#endif
#ifdef SUPPORT_DMARC
[ACLC_DMARC_STATUS] = { US"dmarc_status", TRUE, FALSE, (unsigned int) ~ACL_BIT_DATA },
#endif
/* Explicit key lookups can be made in non-smtp ACLs so pass
always and check in the verify processing itself. */
[ACLC_DNSLISTS] = { US"dnslists", TRUE, FALSE, 0 },
[ACLC_DOMAINS] = { US"domains", FALSE, FALSE,
(unsigned int)
~(ACL_BIT_RCPT | ACL_BIT_VRFY
#ifndef DISABLE_PRDR
|ACL_BIT_PRDR
#endif
),
},
[ACLC_ENCRYPTED] = { US"encrypted", FALSE, FALSE,
ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START |
ACL_BIT_HELO,
},
[ACLC_ENDPASS] = { US"endpass", TRUE, TRUE, 0 },
[ACLC_HOSTS] = { US"hosts", FALSE, FALSE,
ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START,
},
[ACLC_LOCAL_PARTS] = { US"local_parts", FALSE, FALSE,
(unsigned int)
~(ACL_BIT_RCPT | ACL_BIT_VRFY
#ifndef DISABLE_PRDR
| ACL_BIT_PRDR
#endif
),
},
[ACLC_LOG_MESSAGE] = { US"log_message", TRUE, TRUE, 0 },
[ACLC_LOG_REJECT_TARGET] = { US"log_reject_target", TRUE, TRUE, 0 },
[ACLC_LOGWRITE] = { US"logwrite", TRUE, TRUE, 0 },
#ifdef WITH_CONTENT_SCAN
[ACLC_MALWARE] = { US"malware", TRUE, FALSE,
(unsigned int)
~(ACL_BIT_DATA |
# ifndef DISABLE_PRDR
ACL_BIT_PRDR |
# endif
ACL_BIT_NOTSMTP),
},
#endif
[ACLC_MESSAGE] = { US"message", TRUE, TRUE, 0 },
#ifdef WITH_CONTENT_SCAN
[ACLC_MIME_REGEX] = { US"mime_regex", TRUE, FALSE, (unsigned int) ~ACL_BIT_MIME },
#endif
[ACLC_QUEUE] = { US"queue", TRUE, TRUE,
ACL_BIT_NOTSMTP |
#ifndef DISABLE_PRDR
ACL_BIT_PRDR |
#endif
ACL_BIT_DATA,
},
[ACLC_RATELIMIT] = { US"ratelimit", TRUE, FALSE, 0 },
[ACLC_RECIPIENTS] = { US"recipients", FALSE, FALSE, (unsigned int) ~ACL_BIT_RCPT },
#ifdef WITH_CONTENT_SCAN
[ACLC_REGEX] = { US"regex", TRUE, FALSE,
(unsigned int)
~(ACL_BIT_DATA |
# ifndef DISABLE_PRDR
ACL_BIT_PRDR |
# endif
ACL_BIT_NOTSMTP |
ACL_BIT_MIME),
},
#endif
[ACLC_REMOVE_HEADER] = { US"remove_header", TRUE, TRUE,
(unsigned int)
~(ACL_BIT_MAIL|ACL_BIT_RCPT |
ACL_BIT_PREDATA | ACL_BIT_DATA |
#ifndef DISABLE_PRDR
ACL_BIT_PRDR |
#endif
ACL_BIT_MIME | ACL_BIT_NOTSMTP |
ACL_BIT_NOTSMTP_START),
},
[ACLC_SEEN] = { US"seen", TRUE, FALSE, 0 },
[ACLC_SENDER_DOMAINS] = { US"sender_domains", FALSE, FALSE,
ACL_BIT_AUTH | ACL_BIT_CONNECT |
ACL_BIT_HELO |
ACL_BIT_MAILAUTH | ACL_BIT_QUIT |
ACL_BIT_ETRN | ACL_BIT_EXPN |
ACL_BIT_STARTTLS | ACL_BIT_VRFY,
},
[ACLC_SENDERS] = { US"senders", FALSE, FALSE,
ACL_BIT_AUTH | ACL_BIT_CONNECT |
ACL_BIT_HELO |
ACL_BIT_MAILAUTH | ACL_BIT_QUIT |
ACL_BIT_ETRN | ACL_BIT_EXPN |
ACL_BIT_STARTTLS | ACL_BIT_VRFY,
},
[ACLC_SET] = { US"set", TRUE, TRUE, 0 },
#ifdef WITH_CONTENT_SCAN
[ACLC_SPAM] = { US"spam", TRUE, FALSE,
(unsigned int) ~(ACL_BIT_DATA |
# ifndef DISABLE_PRDR
ACL_BIT_PRDR |
# endif
ACL_BIT_NOTSMTP),
},
#endif
#ifdef SUPPORT_SPF
[ACLC_SPF] = { US"spf", TRUE, FALSE,
ACL_BIT_AUTH | ACL_BIT_CONNECT |
ACL_BIT_HELO | ACL_BIT_MAILAUTH |
ACL_BIT_ETRN | ACL_BIT_EXPN |
ACL_BIT_STARTTLS | ACL_BIT_VRFY |
ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START,
},
[ACLC_SPF_GUESS] = { US"spf_guess", TRUE, FALSE,
ACL_BIT_AUTH | ACL_BIT_CONNECT |
ACL_BIT_HELO | ACL_BIT_MAILAUTH |
ACL_BIT_ETRN | ACL_BIT_EXPN |
ACL_BIT_STARTTLS | ACL_BIT_VRFY |
ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START,
},
#endif
[ACLC_UDPSEND] = { US"udpsend", TRUE, TRUE, 0 },
/* Certain types of verify are always allowed, so we let it through
always and check in the verify function itself */
[ACLC_VERIFY] = { US"verify", TRUE, FALSE, 0 },
};
#ifdef MACRO_PREDEF
# include "macro_predef.h"
void
features_acl(void)
{
for (condition_def * c = conditions; c < conditions + nelem(conditions); c++)
{
uschar buf[64], * p, * s;
int n = sprintf(CS buf, "_ACL_%s_", c->is_modifier ? "MOD" : "COND");
for (p = buf + n, s = c->name; *s; s++) *p++ = toupper(*s);
*p = '\0';
builtin_macro_create(buf);
}
}
#endif
#ifndef MACRO_PREDEF
/* Return values from decode_control(); used as index so keep in step
with the controls_list table that follows! */
enum {
CONTROL_AUTH_UNADVERTISED,
#ifdef EXPERIMENTAL_BRIGHTMAIL
CONTROL_BMI_RUN,
#endif
CONTROL_CASEFUL_LOCAL_PART,
CONTROL_CASELOWER_LOCAL_PART,
CONTROL_CUTTHROUGH_DELIVERY,
CONTROL_DEBUG,
#ifndef DISABLE_DKIM
CONTROL_DKIM_VERIFY,
#endif
#ifdef SUPPORT_DMARC
CONTROL_DMARC_VERIFY,
CONTROL_DMARC_FORENSIC,
#endif
CONTROL_DSCP,
CONTROL_ENFORCE_SYNC,
CONTROL_ERROR, /* pseudo-value for decode errors */
CONTROL_FAKEDEFER,
CONTROL_FAKEREJECT,
CONTROL_FREEZE,
CONTROL_NO_CALLOUT_FLUSH,
CONTROL_NO_DELAY_FLUSH,
CONTROL_NO_ENFORCE_SYNC,
#ifdef WITH_CONTENT_SCAN
CONTROL_NO_MBOX_UNSPOOL,
#endif
CONTROL_NO_MULTILINE,
CONTROL_NO_PIPELINING,
CONTROL_QUEUE,
CONTROL_SUBMISSION,
CONTROL_SUPPRESS_LOCAL_FIXUPS,
#ifdef SUPPORT_I18N
CONTROL_UTF8_DOWNCONVERT,
#endif
};
/* Structure listing various control arguments, with their characteristics.
For each control, there's a bitmap of dis-allowed times. For some, it is easier
to specify the negation of a small number of allowed times. */
typedef struct control_def {
uschar *name;
BOOL has_option; /* Has /option(s) following */
unsigned forbids; /* bitmap of dis-allowed times */
} control_def;
static control_def controls_list[] = {
/* name has_option forbids */
[CONTROL_AUTH_UNADVERTISED] =
{ US"allow_auth_unadvertised", FALSE,
(unsigned)
~(ACL_BIT_CONNECT | ACL_BIT_HELO)
},
#ifdef EXPERIMENTAL_BRIGHTMAIL
[CONTROL_BMI_RUN] =
{ US"bmi_run", FALSE, 0 },
#endif
[CONTROL_CASEFUL_LOCAL_PART] =
{ US"caseful_local_part", FALSE, (unsigned) ~ACL_BIT_RCPT },
[CONTROL_CASELOWER_LOCAL_PART] =
{ US"caselower_local_part", FALSE, (unsigned) ~ACL_BIT_RCPT },
[CONTROL_CUTTHROUGH_DELIVERY] =
{ US"cutthrough_delivery", TRUE, 0 },
[CONTROL_DEBUG] =
{ US"debug", TRUE, 0 },
#ifndef DISABLE_DKIM
[CONTROL_DKIM_VERIFY] =
{ US"dkim_disable_verify", FALSE,
ACL_BIT_DATA | ACL_BIT_NOTSMTP |
# ifndef DISABLE_PRDR
ACL_BIT_PRDR |
# endif
ACL_BIT_NOTSMTP_START
},
#endif
#ifdef SUPPORT_DMARC
[CONTROL_DMARC_VERIFY] =
{ US"dmarc_disable_verify", FALSE,
ACL_BIT_DATA | ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
},
[CONTROL_DMARC_FORENSIC] =
{ US"dmarc_enable_forensic", FALSE,
ACL_BIT_DATA | ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
},
#endif
[CONTROL_DSCP] =
{ US"dscp", TRUE,
ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START | ACL_BIT_NOTQUIT
},
[CONTROL_ENFORCE_SYNC] =
{ US"enforce_sync", FALSE,
ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
},
/* Pseudo-value for decode errors */
[CONTROL_ERROR] =
{ US"error", FALSE, 0 },
[CONTROL_FAKEDEFER] =
{ US"fakedefer", TRUE,
(unsigned)
~(ACL_BIT_MAIL | ACL_BIT_RCPT |
ACL_BIT_PREDATA | ACL_BIT_DATA |
#ifndef DISABLE_PRDR
ACL_BIT_PRDR |
#endif
ACL_BIT_MIME)
},
[CONTROL_FAKEREJECT] =
{ US"fakereject", TRUE,
(unsigned)
~(ACL_BIT_MAIL | ACL_BIT_RCPT |
ACL_BIT_PREDATA | ACL_BIT_DATA |
#ifndef DISABLE_PRDR
ACL_BIT_PRDR |
#endif
ACL_BIT_MIME)
},
[CONTROL_FREEZE] =
{ US"freeze", TRUE,
(unsigned)
~(ACL_BIT_MAIL | ACL_BIT_RCPT |
ACL_BIT_PREDATA | ACL_BIT_DATA |
// ACL_BIT_PRDR| /* Not allow one user to freeze for all */
ACL_BIT_NOTSMTP | ACL_BIT_MIME)
},
[CONTROL_NO_CALLOUT_FLUSH] =
{ US"no_callout_flush", FALSE,
ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
},
[CONTROL_NO_DELAY_FLUSH] =
{ US"no_delay_flush", FALSE,
ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
},
[CONTROL_NO_ENFORCE_SYNC] =
{ US"no_enforce_sync", FALSE,
ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
},
#ifdef WITH_CONTENT_SCAN
[CONTROL_NO_MBOX_UNSPOOL] =
{ US"no_mbox_unspool", FALSE,
(unsigned)
~(ACL_BIT_MAIL | ACL_BIT_RCPT |
ACL_BIT_PREDATA | ACL_BIT_DATA |
// ACL_BIT_PRDR| /* Not allow one user to freeze for all */
ACL_BIT_MIME)
},
#endif
[CONTROL_NO_MULTILINE] =
{ US"no_multiline_responses", FALSE,
ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
},
[CONTROL_NO_PIPELINING] =
{ US"no_pipelining", FALSE,
ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
},
[CONTROL_QUEUE] =
{ US"queue", TRUE,
(unsigned)
~(ACL_BIT_MAIL | ACL_BIT_RCPT |
ACL_BIT_PREDATA | ACL_BIT_DATA |
// ACL_BIT_PRDR| /* Not allow one user to freeze for all */
ACL_BIT_NOTSMTP | ACL_BIT_MIME)
},
[CONTROL_SUBMISSION] =
{ US"submission", TRUE,
(unsigned)
~(ACL_BIT_MAIL | ACL_BIT_RCPT | ACL_BIT_PREDATA)
},
[CONTROL_SUPPRESS_LOCAL_FIXUPS] =
{ US"suppress_local_fixups", FALSE,
(unsigned)
~(ACL_BIT_MAIL | ACL_BIT_RCPT | ACL_BIT_PREDATA |
ACL_BIT_NOTSMTP_START)
},
#ifdef SUPPORT_I18N
[CONTROL_UTF8_DOWNCONVERT] =
{ US"utf8_downconvert", TRUE, (unsigned) ~(ACL_BIT_RCPT | ACL_BIT_VRFY)
}
#endif
};
/* Support data structures for Client SMTP Authorization. acl_verify_csa()
caches its result in a tree to avoid repeated DNS queries. The result is an
integer code which is used as an index into the following tables of
explanatory strings and verification return codes. */
static tree_node *csa_cache = NULL;
enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
/* The acl_verify_csa() return code is translated into an acl_verify() return
code using the following table. It is OK unless the client is definitely not
authorized. This is because CSA is supposed to be optional for sending sites,
so recipients should not be too strict about checking it - especially because
DNS problems are quite likely to occur. It's possible to use $csa_status in
further ACL conditions to distinguish ok, unknown, and defer if required, but
the aim is to make the usual configuration simple. */
static int csa_return_code[] = {
[CSA_UNKNOWN] = OK,
[CSA_OK] = OK,
[CSA_DEFER_SRV] = OK,
[CSA_DEFER_ADDR] = OK,
[CSA_FAIL_EXPLICIT] = FAIL,
[CSA_FAIL_DOMAIN] = FAIL,
[CSA_FAIL_NOADDR] = FAIL,
[CSA_FAIL_MISMATCH] = FAIL
};
static uschar *csa_status_string[] = {
[CSA_UNKNOWN] = US"unknown",
[CSA_OK] = US"ok",
[CSA_DEFER_SRV] = US"defer",
[CSA_DEFER_ADDR] = US"defer",
[CSA_FAIL_EXPLICIT] = US"fail",
[CSA_FAIL_DOMAIN] = US"fail",
[CSA_FAIL_NOADDR] = US"fail",
[CSA_FAIL_MISMATCH] = US"fail"
};
static uschar *csa_reason_string[] = {
[CSA_UNKNOWN] = US"unknown",
[CSA_OK] = US"ok",
[CSA_DEFER_SRV] = US"deferred (SRV lookup failed)",
[CSA_DEFER_ADDR] = US"deferred (target address lookup failed)",
[CSA_FAIL_EXPLICIT] = US"failed (explicit authorization required)",
[CSA_FAIL_DOMAIN] = US"failed (host name not authorized)",
[CSA_FAIL_NOADDR] = US"failed (no authorized addresses)",
[CSA_FAIL_MISMATCH] = US"failed (client address mismatch)"
};
/* Options for the ratelimit condition. Note that there are two variants of
the per_rcpt option, depending on the ACL that is used to measure the rate.
However any ACL must be able to look up per_rcpt rates in /noupdate mode,
so the two variants must have the same internal representation as well as
the same configuration string. */
enum {
RATE_PER_WHAT, RATE_PER_CLASH, RATE_PER_ADDR, RATE_PER_BYTE, RATE_PER_CMD,
RATE_PER_CONN, RATE_PER_MAIL, RATE_PER_RCPT, RATE_PER_ALLRCPTS
};
#define RATE_SET(var,new) \
(((var) == RATE_PER_WHAT) ? ((var) = RATE_##new) : ((var) = RATE_PER_CLASH))
static uschar *ratelimit_option_string[] = {
[RATE_PER_WHAT] = US"?",
[RATE_PER_CLASH] = US"!",
[RATE_PER_ADDR] = US"per_addr",
[RATE_PER_BYTE] = US"per_byte",
[RATE_PER_CMD] = US"per_cmd",
[RATE_PER_CONN] = US"per_conn",
[RATE_PER_MAIL] = US"per_mail",
[RATE_PER_RCPT] = US"per_rcpt",
[RATE_PER_ALLRCPTS] = US"per_rcpt"
};
/* Enable recursion between acl_check_internal() and acl_check_condition() */
static int acl_check_wargs(int, address_item *, const uschar *, uschar **,
uschar **);
/*************************************************
* Find control in list *
*************************************************/
/* The lists are always in order, so binary chop can be used.
Arguments:
name the control name to search for
ol the first entry in the control list
last one more than the offset of the last entry in the control list
Returns: index of a control entry, or -1 if not found
*/
static int
find_control(const uschar * name, control_def * ol, int last)
{
for (int first = 0; last > first; )
{
int middle = (first + last)/2;
uschar * s = ol[middle].name;
int c = Ustrncmp(name, s, Ustrlen(s));
if (c == 0) return middle;
else if (c > 0) first = middle + 1;
else last = middle;
}
return -1;
}
/*************************************************
* Pick out condition from list *
*************************************************/
/* Use a binary chop method
Arguments:
name name to find
list list of conditions
end size of list
Returns: offset in list, or -1 if not found
*/
static int
acl_checkcondition(uschar * name, condition_def * list, int end)
{
for (int start = 0; start < end; )
{
int mid = (start + end)/2;
int c = Ustrcmp(name, list[mid].name);
if (c == 0) return mid;
if (c < 0) end = mid;
else start = mid + 1;
}
return -1;
}
/*************************************************
* Pick out name from list *
*************************************************/
/* Use a binary chop method
Arguments:
name name to find
list list of names
end size of list
Returns: offset in list, or -1 if not found
*/
static int
acl_checkname(uschar *name, uschar **list, int end)
{
for (int start = 0; start < end; )
{
int mid = (start + end)/2;
int c = Ustrcmp(name, list[mid]);
if (c == 0) return mid;
if (c < 0) end = mid; else start = mid + 1;
}
return -1;
}
/*************************************************
* Read and parse one ACL *
*************************************************/
/* This function is called both from readconf in order to parse the ACLs in the
configuration file, and also when an ACL is encountered dynamically (e.g. as
the result of an expansion). It is given a function to call in order to
retrieve the lines of the ACL. This function handles skipping comments and
blank lines (where relevant).
Arguments:
func function to get next line of ACL
error where to put an error message
Returns: pointer to ACL, or NULL
NULL can be legal (empty ACL); in this case error will be NULL
*/
acl_block *
acl_read(uschar *(*func)(void), uschar **error)
{
acl_block *yield = NULL;
acl_block **lastp = &yield;
acl_block *this = NULL;
acl_condition_block *cond;
acl_condition_block **condp = NULL;
uschar * s;
*error = NULL;
while ((s = (*func)()))
{
int v, c;
BOOL negated = FALSE;
uschar *saveline = s;
uschar name[EXIM_DRIVERNAME_MAX];
/* Conditions (but not verbs) are allowed to be negated by an initial
exclamation mark. */
if (Uskip_whitespace(&s) == '!')
{
negated = TRUE;
s++;
}
/* Read the name of a verb or a condition, or the start of a new ACL, which
can be started by a name, or by a macro definition. */
s = readconf_readname(name, sizeof(name), s);
if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
/* If a verb is unrecognized, it may be another condition or modifier that
continues the previous verb. */
if ((v = acl_checkname(name, verbs, nelem(verbs))) < 0)
{
if (!this)
{
*error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
saveline);
return NULL;
}
}
/* New verb */
else
{
if (negated)
{
*error = string_sprintf("malformed ACL line \"%s\"", saveline);
return NULL;
}
this = store_get(sizeof(acl_block), FALSE);
*lastp = this;
lastp = &(this->next);
this->next = NULL;
this->condition = NULL;
this->verb = v;
this->srcline = config_lineno; /* for debug output */
this->srcfile = config_filename; /**/
condp = &(this->condition);
if (*s == 0) continue; /* No condition on this line */
if (*s == '!')
{
negated = TRUE;
s++;
}
s = readconf_readname(name, sizeof(name), s); /* Condition name */
}
/* Handle a condition or modifier. */
if ((c = acl_checkcondition(name, conditions, nelem(conditions))) < 0)
{
*error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
saveline);
return NULL;
}
/* The modifiers may not be negated */
if (negated && conditions[c].is_modifier)
{
*error = string_sprintf("ACL error: negation is not allowed with "
"\"%s\"", conditions[c].name);
return NULL;
}
/* ENDPASS may occur only with ACCEPT or DISCARD. */
if (c == ACLC_ENDPASS &&
this->verb != ACL_ACCEPT &&
this->verb != ACL_DISCARD)
{
*error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
conditions[c].name, verbs[this->verb]);
return NULL;
}
cond = store_get(sizeof(acl_condition_block), FALSE);
cond->next = NULL;
cond->type = c;
cond->u.negated = negated;
*condp = cond;
condp = &(cond->next);
/* The "set" modifier is different in that its argument is "name=value"
rather than just a value, and we can check the validity of the name, which
gives us a variable name to insert into the data block. The original ACL
variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
extended to 20 of each type, but after that people successfully argued for
arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
After that, we allow alphanumerics and underscores, but the first character
after c or m must be a digit or an underscore. This retains backwards
compatibility. */
if (c == ACLC_SET)
#ifndef DISABLE_DKIM
if ( Ustrncmp(s, "dkim_verify_status", 18) == 0
|| Ustrncmp(s, "dkim_verify_reason", 18) == 0)
{
uschar * endptr = s+18;
if (isalnum(*endptr))
{
*error = string_sprintf("invalid variable name after \"set\" in ACL "
"modifier \"set %s\" "
"(only \"dkim_verify_status\" or \"dkim_verify_reason\" permitted)",
s);
return NULL;
}
cond->u.varname = string_copyn(s, 18);
s = endptr;
Uskip_whitespace(&s);
}
else
#endif
{
uschar *endptr;
if (Ustrncmp(s, "acl_c", 5) != 0 && Ustrncmp(s, "acl_m", 5) != 0)
{
*error = string_sprintf("invalid variable name after \"set\" in ACL "
"modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
return NULL;
}
endptr = s + 5;
if (!isdigit(*endptr) && *endptr != '_')
{
*error = string_sprintf("invalid variable name after \"set\" in ACL "
"modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
s);
return NULL;
}
while (*endptr && *endptr != '=' && !isspace(*endptr))
{
if (!isalnum(*endptr) && *endptr != '_')
{
*error = string_sprintf("invalid character \"%c\" in variable name "
"in ACL modifier \"set %s\"", *endptr, s);
return NULL;
}
endptr++;
}
cond->u.varname = string_copyn(s + 4, endptr - s - 4);
s = endptr;
Uskip_whitespace(&s);
}
/* For "set", we are now positioned for the data. For the others, only
"endpass" has no data */
if (c != ACLC_ENDPASS)
{
if (*s++ != '=')
{
*error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
conditions[c].is_modifier ? US"modifier" : US"condition");
return NULL;
}
Uskip_whitespace(&s);
cond->arg = string_copy(s);
}
}
return yield;
}
/*************************************************
* Set up added header line(s) *
*************************************************/
/* This function is called by the add_header modifier, and also from acl_warn()
to implement the now-deprecated way of adding header lines using "message" on a
"warn" verb. The argument is treated as a sequence of header lines which are
added to a chain, provided there isn't an identical one already there.
Argument: string of header lines
Returns: nothing
*/
static void
setup_header(const uschar *hstring)
{
const uschar *p, *q;
int hlen = Ustrlen(hstring);
/* Ignore any leading newlines */
while (*hstring == '\n') hstring++, hlen--;
/* An empty string does nothing; ensure exactly one final newline. */
if (hlen <= 0) return;
if (hstring[--hlen] != '\n') /* no newline */
q = string_sprintf("%s\n", hstring);
else if (hstring[hlen-1] == '\n') /* double newline */
{
uschar * s = string_copy(hstring);
while(s[--hlen] == '\n')
s[hlen+1] = '\0';
q = s;
}
else
q = hstring;
/* Loop for multiple header lines, taking care about continuations */
for (p = q; *p; p = q)
{
const uschar *s;
uschar * hdr;
int newtype = htype_add_bot;
header_line **hptr = &acl_added_headers;
/* Find next header line within the string */
for (;;)
{
q = Ustrchr(q, '\n'); /* we know there was a newline */