match_service.c

[詳解]

/*++
/* NAME
/*  match_service 3
/* SUMMARY
/*  simple master.cf service name.type pattern matcher
/* SYNOPSIS
/*  #include <match_service.h>
/*
/*  ARGV    *match_service_init(pattern_list)
/*  const char *pattern_list;
/*
/*  ARGV    *match_service_init_argv(pattern_list)
/*  char    **pattern_list;
/*
/*  int match_service_match(list, name_type)
/*  ARGV    *list;
/*  const char *name_type;
/*
/*  void match_service_free(list)
/*  ARGV    *list;
/* DESCRIPTION
/*  This module implements pattern matching for Postfix master.cf
/*  services.  This is more precise than using domain_list(3),
/*  because match_service(3) won't treat a dotted service name
/*  as a domain hierarchy. Moreover, this module has the advantage
/*  that it does not drag in all the LDAP, SQL and other map
/*  lookup client code into programs that don't need it.
/*
/*  Each pattern is of the form "name/type" or "type", where
/*  "name" and "type" are the first two fields of a master.cf
/*  entry. Patterns are separated by whitespace and/or commas.
/*  Matches are case insensitive. Patterns are matched in the
/*  specified order, and the matching process stops at the first
/*  match.  In order to reverse the result of a pattern match,
/*  precede a pattern with an exclamation point (!).
/*
/*  For backwards compatibility, the form name.type is still
/*  supported.
/*
/*  match_service_init() parses the pattern list. The result
/*  must be passed to match_service_match() or match_service_free().
/*
/*  match_service_init_argv() provides an alternate interface
/*  for pre-parsed strings.
/*
/*  match_service_match() matches one service name.type string
/*  against the specified pattern list.
/*
/*  match_service_free() releases storage allocated by
/*  match_service_init().
/* DIAGNOSTICS
/*  Fatal error: out of memory, malformed pattern.
/*  Panic: malformed search string.
/* SEE ALSO
/*  domain_list(3) match domain names.
/* 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
/*--*/

/* System library. */

#include <sys_defs.h>
#include <string.h>

#ifdef STRCASECMP_IN_STRINGS_H
#include <strings.h>
#endif

/* Utility library. */

#include <msg.h>
#include <argv.h>
#include <mymalloc.h>
#include <stringops.h>
#include <match_service.h>

/* match_service_compat - backwards compatibility */

static void match_service_compat(ARGV *argv)
{
    char  **cpp;
    char   *cp;

    for (cpp = argv->argv; *cpp; cpp++) {
    if (strrchr(*cpp, '/') == 0 && (cp = strrchr(*cpp, '.')) != 0)
        *cp = '/';
    }
}

/* match_service_init - initialize pattern list */

ARGV   *match_service_init(const char *patterns)
{
    const char *delim = CHARS_COMMA_SP;
    ARGV   *list = argv_alloc(1);
    char   *saved_patterns = mystrdup(patterns);
    char   *bp = saved_patterns;
    const char *item;

    while ((item = mystrtok(&bp, delim)) != 0)
    argv_add(list, item, (char *) 0);
    argv_terminate(list);
    myfree(saved_patterns);
    match_service_compat(list);
    return (list);
}

/* match_service_init_argv - impedance adapter */

ARGV   *match_service_init_argv(char **patterns)
{
    ARGV   *list = argv_alloc(1);
    char  **cpp;

    for (cpp = patterns; *cpp; cpp++)
    argv_add(list, *cpp, (char *) 0);
    argv_terminate(list);
    match_service_compat(list);
    return (list);
}

/* match_service_match - match service name.type against pattern list */

int     match_service_match(ARGV *list, const char *name_type)
{
    const char *myname = "match_service_match";
    const char *type;
    char  **cpp;
    char   *pattern;
    int     match;

    /*
     * Quick check for empty list.
     */
    if (list->argv[0] == 0)
    return (0);

    /*
     * Sanity check.
     */
    if ((type = strrchr(name_type, '/')) == 0 || *++type == 0)
    msg_panic("%s: malformed service: \"%s\"; need \"name/type\" format",
          myname, name_type);

    /*
     * Iterate over all patterns in the list, stop at the first match.
     */
    for (cpp = list->argv; (pattern = *cpp) != 0; cpp++) {
    if (msg_verbose)
        msg_info("%s: %s ~? %s", myname, name_type, pattern);
    for (match = 1; *pattern == '!'; pattern++)
        match = !match;
    if (strcasecmp(strchr(pattern, '/') ? name_type : type, pattern) == 0) {
        if (msg_verbose)
        msg_info("%s: %s: found match", myname, name_type);
        return (match);
    }
    }
    if (msg_verbose)
    msg_info("%s: %s: no match", myname, name_type);
    return (0);
}

/* match_service_free - release storage */

void    match_service_free(ARGV *list)
{
    argv_free(list);
}