diff options
Diffstat (limited to 'src/global/dsn_filter.c')
| -rw-r--r-- | src/global/dsn_filter.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/src/global/dsn_filter.c b/src/global/dsn_filter.c new file mode 100644 index 0000000..3ffeb9f --- /dev/null +++ b/src/global/dsn_filter.c @@ -0,0 +1,194 @@ +/*++ +/* NAME +/* dsn_filter 3 +/* SUMMARY +/* filter delivery status code or text +/* SYNOPSIS +/* #include <dsn_filter.h> +/* +/* DSN_FILTER *dsn_filter_create( +/* const char *title, +/* const char *map_names) +/* +/* DSN *dsn_filter_lookup( +/* DSN_FILTER *fp, +/* DSN *dsn) +/* +/* void dsn_filter_free( +/* DSN_FILTER *fp) +/* DESCRIPTION +/* This module maps (bounce or defer non-delivery status code +/* and text) into replacement (bounce or defer non-delivery +/* status code and text), or maps (success status code and +/* text) into replacement (success status code and text). Other +/* DSN attributes are passed through without modification. +/* +/* dsn_filter_create() instantiates a delivery status filter. +/* +/* dsn_filter_lookup() queries the specified filter. The input +/* DSN must be a success, bounce or defer DSN. If a match is +/* found a non-delivery status must map to a non-delivery +/* status, a success status must map to a success status, and +/* the text must be non-empty. The result is a null pointer +/* when no valid match is found. Otherwise, the result is +/* overwritten upon each call. This function must not be +/* called with the result from a dsn_filter_lookup() call. +/* +/* dsn_filter_free() destroys the specified delivery status +/* filter. +/* +/* Arguments: +/* .IP title +/* Origin of the mapnames argument, typically a configuration +/* parameter name. This is reported in diagnostics. +/* .IP mapnames +/* List of lookup tables, separated by whitespace or comma. +/* .IP fp +/* filter created with dsn_filter_create() +/* .IP dsn +/* A success, bounce or defer DSN data structure. The +/* dsn_filter_lookup() result value is in part a shallow copy +/* of this argument. +/* SEE ALSO +/* maps(3) multi-table search +/* DIAGNOSTICS +/* Panic: invalid dsn argument; recursive call. Fatal error: +/* memory allocation problem. Warning: invalid DSN lookup +/* result. +/* 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 libraries. + */ +#include <sys_defs.h> + + /* + * Utility library. + */ +#include <msg.h> +#include <mymalloc.h> +#include <vstring.h> + + /* + * Global library. + */ +#include <maps.h> +#include <dsn.h> +#include <dsn_util.h> +#include <maps.h> +#include <dsn_filter.h> + + /* + * Private data structure. + */ +struct DSN_FILTER { + MAPS *maps; /* Replacement (status, text) */ + VSTRING *buffer; /* Status code and text */ + DSN_SPLIT dp; /* Parsing aid */ + DSN dsn; /* Shallow copy */ +}; + + /* + * SLMs. + */ +#define STR(x) vstring_str(x) + +/* dsn_filter_create - create delivery status filter */ + +DSN_FILTER *dsn_filter_create(const char *title, const char *map_names) +{ + static const char myname[] = "dsn_filter_create"; + DSN_FILTER *fp; + + if (msg_verbose) + msg_info("%s: %s %s", myname, title, map_names); + + fp = (DSN_FILTER *) mymalloc(sizeof(*fp)); + fp->buffer = vstring_alloc(100); + fp->maps = maps_create(title, map_names, DICT_FLAG_LOCK); + return (fp); +} + +/* dsn_filter_lookup - apply delivery status filter */ + +DSN *dsn_filter_lookup(DSN_FILTER *fp, DSN *dsn) +{ + static const char myname[] = "dsn_filter_lookup"; + const char *result; + int ndr_dsn = 0; + + if (msg_verbose) + msg_info("%s: %s %s", myname, dsn->status, dsn->reason); + + /* + * XXX Instead of hard-coded '4' etc., use some form of encapsulation + * when reading or updating the status class field. + */ +#define IS_SUCCESS_DSN(s) (dsn_valid(s) && (s)[0] == '2') +#define IS_NDR_DSN(s) (dsn_valid(s) && ((s)[0] == '4' || (s)[0] == '5')) + + /* + * Sanity check. We filter only success/bounce/defer DSNs. + */ + if (IS_SUCCESS_DSN(dsn->status)) + ndr_dsn = 0; + else if (IS_NDR_DSN(dsn->status)) + ndr_dsn = 1; + else + msg_panic("%s: dsn argument with bad status code: %s", + myname, dsn->status); + + /* + * Sanity check. A delivery status filter must not be invoked with its + * own result. + */ + if (dsn->reason == fp->dsn.reason) + msg_panic("%s: recursive call is not allowed", myname); + + /* + * Look up replacement status and text. + */ + vstring_sprintf(fp->buffer, "%s %s", dsn->status, dsn->reason); + if ((result = maps_find(fp->maps, STR(fp->buffer), 0)) != 0) { + /* Sanity check. Do not allow success<=>error mappings. */ + if ((ndr_dsn == 0 && !IS_SUCCESS_DSN(result)) + || (ndr_dsn != 0 && !IS_NDR_DSN(result))) { + msg_warn("%s: bad status code: %s", fp->maps->title, result); + return (0); + } else { + vstring_strcpy(fp->buffer, result); + dsn_split(&fp->dp, "can't happen", STR(fp->buffer)); + (void) DSN_ASSIGN(&fp->dsn, DSN_STATUS(fp->dp.dsn), + (result[0] == '4' ? "delayed" : + result[0] == '5' ? "failed" : + dsn->action), + fp->dp.text, dsn->dtype, dsn->dtext, + dsn->mtype, dsn->mname); + return (&fp->dsn); + } + } + return (0); +} + +/* dsn_filter_free - destroy delivery status filter */ + +void dsn_filter_free(DSN_FILTER *fp) +{ + static const char myname[] = "dsn_filter_free"; + + if (msg_verbose) + msg_info("%s: %s", myname, fp->maps->title); + + maps_free(fp->maps); + vstring_free(fp->buffer); + myfree((void *) fp); +} |