/*++ /* NAME /* delivered_hdr 3 /* SUMMARY /* process Delivered-To: headers /* SYNOPSIS /* #include <delivered_hdr.h> /* /* DELIVERED_HDR_INFO *delivered_hdr_init(stream, offset, flags) /* VSTREAM *stream; /* off_t offset; /* int flags; /* /* int delivered_hdr_find(info, address) /* DELIVERED_HDR_INFO *info; /* const char *address; /* /* void delivered_hdr_free(info) /* DELIVERED_HDR_INFO *info; /* DESCRIPTION /* This module processes addresses in Delivered-To: headers. /* These headers are added by some mail delivery systems, for the /* purpose of breaking mail forwarding loops. N.B. This solves /* a different problem than the Received: hop count limit. Hop /* counts are used to limit the impact of mail routing problems. /* /* delivered_hdr_init() extracts Delivered-To: header addresses /* from the specified message, and returns a table with the /* result. The file seek pointer is changed. /* /* delivered_hdr_find() looks up the address in the lookup table, /* and returns non-zero when the address was found. The /* address argument must be in internalized form. /* /* delivered_hdr_free() releases storage that was allocated by /* delivered_hdr_init(). /* /* Arguments: /* .IP stream /* The open queue file. /* .IP offset /* Offset of the first message content record. /* .IP flags /* Zero, or the bit-wise OR ot: /* .RS /* .IP FOLD_ADDR_USER /* Case fold the address local part. /* .IP FOLD_ADDR_HOST /* Case fold the address domain part. /* .IP FOLD_ADDR_ALL /* Alias for (FOLD_ADDR_USER | FOLD_ADDR_HOST). /* .RE /* .IP info /* Extracted Delivered-To: addresses information. /* .IP address /* A recipient address, internal form. /* DIAGNOSTICS /* Fatal errors: out of memory. /* SEE ALSO /* mail_copy(3), producer of Delivered-To: and other headers. /* 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 <unistd.h> #include <string.h> #include <ctype.h> /* Utility library. */ #include <msg.h> #include <mymalloc.h> #include <htable.h> #include <vstring.h> #include <vstream.h> #include <vstring_vstream.h> #include <stringops.h> /* Global library. */ #include <record.h> #include <rec_type.h> #include <is_header.h> #include <quote_822_local.h> #include <header_opts.h> #include <delivered_hdr.h> #include <fold_addr.h> /* * Application-specific. */ struct DELIVERED_HDR_INFO { int flags; VSTRING *buf; HTABLE *table; }; #define STR(x) vstring_str(x) /* delivered_hdr_init - extract delivered-to information from the message */ DELIVERED_HDR_INFO *delivered_hdr_init(VSTREAM *fp, off_t offset, int flags) { char *cp; DELIVERED_HDR_INFO *info; const HEADER_OPTS *hdr; /* * Sanity check. */ info = (DELIVERED_HDR_INFO *) mymalloc(sizeof(*info)); info->flags = flags; info->buf = vstring_alloc(10); info->table = htable_create(0); if (vstream_fseek(fp, offset, SEEK_SET) < 0) msg_fatal("seek queue file %s: %m", VSTREAM_PATH(fp)); /* * XXX Assume that mail_copy() produces delivered-to headers that fit in * a REC_TYPE_NORM record. Lowercase the delivered-to addresses for * consistency. * * XXX Don't get bogged down by gazillions of delivered-to headers. */ #define DELIVERED_HDR_LIMIT 1000 while (rec_get(fp, info->buf, 0) == REC_TYPE_NORM && info->table->used < DELIVERED_HDR_LIMIT) { if (is_header(STR(info->buf))) { if ((hdr = header_opts_find(STR(info->buf))) != 0 && hdr->type == HDR_DELIVERED_TO) { cp = STR(info->buf) + strlen(hdr->name) + 1; while (ISSPACE(*cp)) cp++; if (info->flags & FOLD_ADDR_ALL) fold_addr(cp, info->flags); if (msg_verbose) msg_info("delivered_hdr_init: %s", cp); htable_enter(info->table, cp, (char *) 0); } } else if (ISSPACE(STR(info->buf)[0])) { continue; } else { break; } } return (info); } /* delivered_hdr_find - look up recipient in delivered table */ int delivered_hdr_find(DELIVERED_HDR_INFO *info, const char *address) { HTABLE_INFO *ht; /* * mail_copy() uses quote_822_local() when writing the Delivered-To: * header. We must therefore apply the same transformation when looking * up the recipient. Lowercase the delivered-to address for consistency. */ quote_822_local(info->buf, address); if (info->flags & FOLD_ADDR_ALL) fold_addr(STR(info->buf), info->flags); ht = htable_locate(info->table, STR(info->buf)); return (ht != 0); } /* delivered_hdr_free - destructor */ void delivered_hdr_free(DELIVERED_HDR_INFO *info) { vstring_free(info->buf); htable_free(info->table, (void (*) (char *)) 0); myfree((char *) info); }