diff options
Diffstat (limited to 'src/spool_out.c')
| -rw-r--r-- | src/spool_out.c | 580 |
1 files changed, 580 insertions, 0 deletions
diff --git a/src/spool_out.c b/src/spool_out.c new file mode 100644 index 0000000..510eda6 --- /dev/null +++ b/src/spool_out.c @@ -0,0 +1,580 @@ +/************************************************* +* Exim - an Internet mail transport agent * +*************************************************/ + +/* Copyright (c) The Exim Maintainers 2020 - 2022 */ +/* Copyright (c) University of Cambridge 1995 - 2018 */ +/* See the file NOTICE for conditions of use and distribution. */ + +/* Functions for writing spool files, and moving them about. */ + + +#include "exim.h" + + + +/************************************************* +* Deal with header writing errors * +*************************************************/ + +/* This function is called immediately after errors in writing the spool, with +errno still set. It creates an error message, depending on the circumstances. +If errmsg is NULL, it logs the message and panic-dies. Otherwise errmsg is set +to point to the message, and -1 is returned. This function makes the code of +spool_write_header() a bit neater. + +Arguments: + where SW_RECEIVING, SW_DELIVERING, or SW_MODIFYING + errmsg where to put the message; NULL => panic-die + s text to add to log string + temp_name name of temp file to unlink + f FILE to close, if not NULL + +Returns: -1 if errmsg is not NULL; otherwise doesn't return +*/ + +static int +spool_write_error(int where, uschar **errmsg, uschar *s, uschar *temp_name, + FILE *f) +{ +uschar *msg = where == SW_RECEIVING + ? string_sprintf("spool file %s error while receiving from %s: %s", s, + sender_fullhost ? sender_fullhost : sender_ident, + strerror(errno)) + : string_sprintf("spool file %s error while %s: %s", s, + where == SW_DELIVERING ? "delivering" : "modifying", + strerror(errno)); + +if (temp_name) Uunlink(temp_name); +if (f) (void)fclose(f); + +if (errmsg) + *errmsg = msg; +else + log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s", msg); + +return -1; +} + + + +/************************************************* +* Open file under temporary name * +*************************************************/ + +/* This is used for opening spool files under a temporary name, +with a single attempt at deleting if they already exist. + +Argument: temporary name for spool header file +Returns: file descriptor of open file, or < 0 on failure, with errno unchanged +*/ + +int +spool_open_temp(uschar *temp_name) +{ +int fd = Uopen(temp_name, O_RDWR|O_CREAT|O_EXCL, SPOOL_MODE); + +/* If the file already exists, something has gone wrong. This process may well +have previously created the file if it is delivering more than one address, but +it should have renamed it almost immediately. A file could, however, be left +around as a result of a system crash, and by coincidence this process might +have the same pid. We therefore have one go at unlinking it before giving up. +*/ + +if (fd < 0 && errno == EEXIST) + { + DEBUG(D_any) debug_printf("%s exists: unlinking\n", temp_name); + Uunlink(temp_name); + fd = Uopen(temp_name, O_RDWR|O_CREAT|O_EXCL, SPOOL_MODE); + } + +/* If the file has been opened, make sure the file's group is the Exim gid, and +double-check the mode because the group setting doesn't always get set +automatically. */ + +if (fd >= 0) + if (exim_fchown(fd, exim_uid, exim_gid, temp_name) || fchmod(fd, SPOOL_MODE)) + { + DEBUG(D_any) debug_printf("failed setting perms on %s\n", temp_name); + (void) close(fd); fd = -1; + Uunlink(temp_name); + } + +return fd; +} + + + +static const uschar * +zap_newlines(const uschar *s) +{ +uschar *z, *p; + +if (Ustrchr(s, '\n') == NULL) return s; + +p = z = string_copy(s); +while ((p = Ustrchr(p, '\n')) != NULL) *p++ = ' '; +return z; +} + +static void +spool_var_write(FILE * fp, const uschar * name, const uschar * val) +{ +putc('-', fp); +if (is_tainted(val)) + { + int q = quoter_for_address(val); + putc('-', fp); + if (is_real_quoter(q)) fprintf(fp, "(%s)", lookup_list[q]->name); + } +fprintf(fp, "%s %s\n", name, val); +} + +/************************************************* +* Write the header spool file * +*************************************************/ + +/* Returns the size of the file for success; zero for failure. The file is +written under a temporary name, and then renamed. It's done this way so that it +works with re-writing the file on message deferral as well as for the initial +write. Whenever this function is called, the data file for the message should +be open and locked, thus preventing any other exim process from working on this +message. + +Argument: + id the message id + where SW_RECEIVING, SW_DELIVERING, or SW_MODIFYING + errmsg where to put an error message; if NULL, panic-die on error + +Returns: the size of the header texts on success; + negative on writing failure, unless errmsg == NULL +*/ + +int +spool_write_header(uschar *id, int where, uschar **errmsg) +{ +int fd; +int size_correction; +FILE * fp; +struct stat statbuf; +uschar * tname; +uschar * fname; + +tname = spool_fname(US"input", message_subdir, US"hdr.", message_id); + +if ((fd = spool_open_temp(tname)) < 0) + return spool_write_error(where, errmsg, US"open", NULL, NULL); +fp = fdopen(fd, "wb"); +DEBUG(D_receive|D_deliver) debug_printf("Writing spool header file: %s\n", tname); + +/* We now have an open file to which the header data is to be written. Start +with the file's leaf name, to make the file self-identifying. Continue with the +identity of the submitting user, followed by the sender's address. The sender's +address is enclosed in <> because it might be the null address. Then write the +received time and the number of warning messages that have been sent. */ + +fprintf(fp, "%s-H\n", message_id); +fprintf(fp, "%.63s %ld %ld\n", originator_login, (long int)originator_uid, + (long int)originator_gid); +fprintf(fp, "<%s>\n", sender_address); +fprintf(fp, "%d %d\n", (int)received_time.tv_sec, warning_count); + +fprintf(fp, "-received_time_usec .%06d\n", (int)received_time.tv_usec); +fprintf(fp, "-received_time_complete %d.%06d\n", + (int)received_time_complete.tv_sec, (int)received_time_complete.tv_usec); + +/* If there is information about a sending host, remember it. The HELO +data can be set for local SMTP as well as remote. */ + +if (sender_helo_name) spool_var_write(fp, US"helo_name", sender_helo_name); + +if (sender_host_address) + { + if (is_tainted(sender_host_address)) putc('-', fp); + fprintf(fp, "-host_address [%s]:%d\n", sender_host_address, sender_host_port); + if (sender_host_name) + spool_var_write(fp, US"host_name", sender_host_name); + } +if (sender_host_authenticated) + spool_var_write(fp, US"host_auth", sender_host_authenticated); +if (sender_host_auth_pubname) + spool_var_write(fp, US"host_auth_pubname", sender_host_auth_pubname); + +/* Also about the interface a message came in on */ + +if (interface_address) + { + if (is_tainted(interface_address)) putc('-', fp); + fprintf(fp, "-interface_address [%s]:%d\n", interface_address, interface_port); + } + +if (smtp_active_hostname != primary_hostname) + spool_var_write(fp, US"active_hostname", smtp_active_hostname); + +/* Likewise for any ident information; for local messages this is +likely to be the same as originator_login, but will be different if +the originator was root, forcing a different ident. */ + +if (sender_ident) + spool_var_write(fp, US"ident", sender_ident); + +/* Ditto for the received protocol */ + +if (received_protocol) + spool_var_write(fp, US"received_protocol", received_protocol); + +/* Preserve any ACL variables that are set. */ + +tree_walk(acl_var_c, &acl_var_write, fp); +tree_walk(acl_var_m, &acl_var_write, fp); + +/* Now any other data that needs to be remembered. */ + +if (*debuglog_name) + { + fprintf(fp, "-debug_selector 0x%x\n", debug_selector); + fprintf(fp, "-debuglog_name %s\n", debuglog_name); + } + +if (f.spool_file_wireformat) + fprintf(fp, "-spool_file_wireformat\n"); +else + fprintf(fp, "-body_linecount %d\n", body_linecount); +fprintf(fp, "-max_received_linelength %d\n", max_received_linelength); + +if (body_zerocount > 0) fprintf(fp, "-body_zerocount %d\n", body_zerocount); + +if (authenticated_id) + spool_var_write(fp, US"auth_id", authenticated_id); +if (authenticated_sender) + spool_var_write(fp, US"auth_sender", zap_newlines(authenticated_sender)); + +if (f.allow_unqualified_recipient) fprintf(fp, "-allow_unqualified_recipient\n"); +if (f.allow_unqualified_sender) fprintf(fp, "-allow_unqualified_sender\n"); +if (f.deliver_firsttime) fprintf(fp, "-deliver_firsttime\n"); +if (f.deliver_freeze) fprintf(fp, "-frozen " TIME_T_FMT "\n", deliver_frozen_at); +if (f.dont_deliver) fprintf(fp, "-N\n"); +if (host_lookup_deferred) fprintf(fp, "-host_lookup_deferred\n"); +if (host_lookup_failed) fprintf(fp, "-host_lookup_failed\n"); +if (f.sender_local) fprintf(fp, "-local\n"); +if (f.local_error_message) fprintf(fp, "-localerror\n"); +#ifdef HAVE_LOCAL_SCAN +if (local_scan_data) spool_var_write(fp, US"local_scan", local_scan_data); +#endif +#ifdef WITH_CONTENT_SCAN +if (spam_bar) spool_var_write(fp, US"spam_bar", spam_bar); +if (spam_score) spool_var_write(fp, US"spam_score", spam_score); +if (spam_score_int) spool_var_write(fp, US"spam_score_int", spam_score_int); +#endif +if (f.deliver_manual_thaw) fprintf(fp, "-manual_thaw\n"); +if (f.sender_set_untrusted) fprintf(fp, "-sender_set_untrusted\n"); + +#ifdef EXPERIMENTAL_BRIGHTMAIL +if (bmi_verdicts) spool_var_write(fp, US"bmi_verdicts", bmi_verdicts); +#endif + +#ifndef DISABLE_TLS +if (tls_in.certificate_verified) fprintf(fp, "-tls_certificate_verified\n"); +if (tls_in.cipher) spool_var_write(fp, US"tls_cipher", tls_in.cipher); +if (tls_in.peercert) + { + if (tls_export_cert(big_buffer, big_buffer_size, tls_in.peercert)) + fprintf(fp, "--tls_peercert %s\n", CS big_buffer); + } +if (tls_in.peerdn) spool_var_write(fp, US"tls_peerdn", string_printing(tls_in.peerdn)); +if (tls_in.sni) spool_var_write(fp, US"tls_sni", string_printing(tls_in.sni)); +if (tls_in.ourcert) + { + if (tls_export_cert(big_buffer, big_buffer_size, tls_in.ourcert)) + fprintf(fp, "-tls_ourcert %s\n", CS big_buffer); + } +if (tls_in.ocsp) fprintf(fp, "-tls_ocsp %d\n", tls_in.ocsp); +# ifndef DISABLE_TLS_RESUME +fprintf(fp, "-tls_resumption %c\n", 'A' + tls_in.resumption); +# endif +if (tls_in.ver) spool_var_write(fp, US"tls_ver", tls_in.ver); +#endif + +#ifdef SUPPORT_I18N +if (message_smtputf8) + { + fprintf(fp, "-smtputf8\n"); + if (message_utf8_downconvert) + fprintf(fp, "-utf8_%sdowncvt\n", message_utf8_downconvert < 0 ? "opt" : ""); + } +#endif + +/* Write the dsn flags to the spool header file */ +/* DEBUG(D_deliver) debug_printf("DSN: Write SPOOL: -dsn_envid %s\n", dsn_envid); */ +if (dsn_envid) fprintf(fp, "-dsn_envid %s\n", dsn_envid); +/* DEBUG(D_deliver) debug_printf("DSN: Write SPOOL: -dsn_ret %d\n", dsn_ret); */ +if (dsn_ret) fprintf(fp, "-dsn_ret %d\n", dsn_ret); + +/* To complete the envelope, write out the tree of non-recipients, followed by +the list of recipients. These won't be disjoint the first time, when no +checking has been done. If a recipient is a "one-time" alias, it is followed by +a space and its parent address number (pno). */ + +tree_write(tree_nonrecipients, fp); +fprintf(fp, "%d\n", recipients_count); +for (int i = 0; i < recipients_count; i++) + { + recipient_item *r = recipients_list + i; + const uschar *address = zap_newlines(r->address); + + /* DEBUG(D_deliver) debug_printf("DSN: Flags: 0x%x\n", r->dsn_flags); */ + + if (r->pno < 0 && !r->errors_to && r->dsn_flags == 0) + fprintf(fp, "%s\n", address); + else + { + const uschar *errors_to = r->errors_to ? zap_newlines(r->errors_to) : CUS""; + /* for DSN SUPPORT extend exim 4 spool in a compatible way by + adding new values upfront and add flag 0x02 */ + const uschar *orcpt = r->orcpt ? zap_newlines(r->orcpt) : CUS""; + + fprintf(fp, "%s %s %d,%d %s %d,%d#3\n", address, orcpt, Ustrlen(orcpt), + r->dsn_flags, errors_to, Ustrlen(errors_to), r->pno); + } + + DEBUG(D_deliver) debug_printf("DSN: **** SPOOL_OUT - " + "address: <%s> errorsto: <%s> orcpt: <%s> dsn_flags: 0x%x\n", + r->address, r->errors_to, r->orcpt, r->dsn_flags); + } + +/* Put a blank line before the headers */ + +fprintf(fp, "\n"); + +/* Save the size of the file so far so we can subtract it from the final length +to get the actual size of the headers. */ + +fflush(fp); +if (fstat(fd, &statbuf)) + return spool_write_error(where, errmsg, US"fstat", tname, fp); +size_correction = statbuf.st_size; + +/* Finally, write out the message's headers. To make it easier to read them +in again, precede each one with the count of its length. Make the count fixed +length to aid human eyes when debugging and arrange for it not be included in +the size. It is followed by a space for normal headers, a flagging letter for +various other headers, or an asterisk for old headers that have been rewritten. +These are saved as a record for debugging. Don't included them in the message's +size. */ + +for (header_line * h = header_list; h; h = h->next) + { + fprintf(fp, "%03d%c %s", h->slen, h->type, h->text); + size_correction += 5; + if (h->type == '*') size_correction += h->slen; + } + +/* Flush and check for any errors while writing */ + +if (fflush(fp) != 0 || ferror(fp)) + return spool_write_error(where, errmsg, US"write", tname, fp); + +/* Force the file's contents to be written to disk. Note that fflush() +just pushes it out of C, and fclose() doesn't guarantee to do the write +either. That's just the way Unix works... */ + +if (EXIMfsync(fileno(fp)) < 0) + return spool_write_error(where, errmsg, US"sync", tname, fp); + +/* Get the size of the file, and close it. */ + +if (fstat(fd, &statbuf) != 0) + return spool_write_error(where, errmsg, US"fstat", tname, NULL); +if (fclose(fp) != 0) + return spool_write_error(where, errmsg, US"close", tname, NULL); + +/* Rename the file to its correct name, thereby replacing any previous +incarnation. */ + +fname = spool_fname(US"input", message_subdir, id, US"-H"); +DEBUG(D_receive|D_deliver) debug_printf("Renaming spool header file: %s\n", fname); + +if (Urename(tname, fname) < 0) + return spool_write_error(where, errmsg, US"rename", tname, NULL); + +/* Linux (and maybe other OS?) does not automatically sync a directory after +an operation like rename. We therefore have to do it forcibly ourselves in +these cases, to make sure the file is actually accessible on disk, as opposed +to just the data being accessible from a file in lost+found. Linux also has +O_DIRECTORY, for opening a directory. + +However, it turns out that some file systems (some versions of NFS?) do not +support directory syncing. It seems safe enough to ignore EINVAL to cope with +these cases. One hack on top of another... but that's life. */ + +#ifdef NEED_SYNC_DIRECTORY + +tname = spool_fname(US"input", message_subdir, US".", US""); + +# ifndef O_DIRECTORY +# define O_DIRECTORY 0 +# endif + +if ((fd = Uopen(tname, O_RDONLY|O_DIRECTORY, 0)) < 0) + return spool_write_error(where, errmsg, US"directory open", fname, NULL); + +if (EXIMfsync(fd) < 0 && errno != EINVAL) + return spool_write_error(where, errmsg, US"directory sync", fname, NULL); + +if (close(fd) < 0) + return spool_write_error(where, errmsg, US"directory close", fname, NULL); + +#endif /* NEED_SYNC_DIRECTORY */ + +/* Return the number of characters in the headers, which is the file size, less +the preliminary stuff, less the additional count fields on the headers. */ + +DEBUG(D_receive) debug_printf("Size of headers = %d\n", + (int)(statbuf.st_size - size_correction)); + +return statbuf.st_size - size_correction; +} + + +/************************************************ +* Make a hard link * +************************************************/ + +/* Used by spool_move_message() below. Note re the use of sprintf(): the value +of spool_directory is checked to ensure that it is less than 200 characters at +start-up time. + +Arguments: + dir base directory name + dq destiinationqueue name + subdir subdirectory name + id message id + suffix suffix to add to id + from source directory prefix + to destination directory prefix + noentok if TRUE, absence of file is not an error + +Returns: TRUE if all went well + FALSE, having panic logged if not +*/ + +static BOOL +make_link(uschar *dir, uschar * dq, uschar *subdir, uschar *id, uschar *suffix, + uschar *from, uschar *to, BOOL noentok) +{ +uschar * fname = spool_fname(string_sprintf("%s%s", from, dir), subdir, id, suffix); +uschar * tname = spool_q_fname(string_sprintf("%s%s", to, dir), dq, subdir, id, suffix); +if (Ulink(fname, tname) < 0 && (!noentok || errno != ENOENT)) + { + log_write(0, LOG_MAIN|LOG_PANIC, "link(\"%s\", \"%s\") failed while moving " + "message: %s", fname, tname, strerror(errno)); + return FALSE; + } +return TRUE; +} + + + +/************************************************ +* Break a link * +************************************************/ + +/* Used by spool_move_message() below. Note re the use of sprintf(): the value +of spool_directory is checked to ensure that it is less than 200 characters at +start-up time. + +Arguments: + dir base directory name + subdir subdirectory name + id message id + suffix suffix to add to id + from source directory prefix + noentok if TRUE, absence of file is not an error + +Returns: TRUE if all went well + FALSE, having panic logged if not +*/ + +static BOOL +break_link(uschar *dir, uschar *subdir, uschar *id, uschar *suffix, uschar *from, + BOOL noentok) +{ +uschar * fname = spool_fname(string_sprintf("%s%s", from, dir), subdir, id, suffix); +if (Uunlink(fname) < 0 && (!noentok || errno != ENOENT)) + { + log_write(0, LOG_MAIN|LOG_PANIC, "unlink(\"%s\") failed while moving " + "message: %s", fname, strerror(errno)); + return FALSE; + } +return TRUE; +} + + + +/************************************************ +* Move message files * +************************************************/ + +/* Move the files for a message (-H, -D, and msglog) from one directory (or +hierarchy) to another. It is assume that there is no -J file in existence when +this is done. + +Arguments: + id the id of the message to be delivered + subdir the subdirectory name, or an empty string + from a prefix for "input" or "msglog" for where the message is now + to a prefix for "input" or "msglog" for where the message is to go + +Returns: TRUE if all is well + FALSE if not, with error logged in panic and main logs +*/ + +BOOL +spool_move_message(uschar *id, uschar *subdir, uschar *from, uschar *to) +{ +uschar * dest_qname = queue_name_dest ? queue_name_dest : queue_name; + +/* Since we are working within the spool, de-taint the dest queue name */ +dest_qname = string_copy_taint(dest_qname, GET_UNTAINTED); + +/* Create any output directories that do not exist. */ + +(void) directory_make(spool_directory, + spool_q_sname(string_sprintf("%sinput", to), dest_qname, subdir), + INPUT_DIRECTORY_MODE, TRUE); +(void) directory_make(spool_directory, + spool_q_sname(string_sprintf("%smsglog", to), dest_qname, subdir), + INPUT_DIRECTORY_MODE, TRUE); + +/* Move the message by first creating new hard links for all the files, and +then removing the old links. When moving messages onto the main spool, the -H +file should be set up last, because that's the one that tells Exim there is a +message to be delivered, so we create its new link last and remove its old link +first. Programs that look at the alternate directories should follow the same +rule of waiting for a -H file before doing anything. When moving messages off +the mail spool, the -D file should be open and locked at the time, thus keeping +Exim's hands off. */ + +if (!make_link(US"msglog", dest_qname, subdir, id, US"", from, to, TRUE) || + !make_link(US"input", dest_qname, subdir, id, US"-D", from, to, FALSE) || + !make_link(US"input", dest_qname, subdir, id, US"-H", from, to, FALSE)) + return FALSE; + +if (!break_link(US"input", subdir, id, US"-H", from, FALSE) || + !break_link(US"input", subdir, id, US"-D", from, FALSE) || + !break_link(US"msglog", subdir, id, US"", from, TRUE)) + return FALSE; + +log_write(0, LOG_MAIN, "moved from %s%s%s%sinput, %smsglog to %s%s%s%sinput, %smsglog", + *queue_name?"(":"", *queue_name?queue_name:US"", *queue_name?") ":"", + from, from, + *dest_qname?"(":"", *dest_qname?dest_qname:US"", *dest_qname?") ":"", + to, to); + +return TRUE; +} + + +/* End of spool_out.c */ +/* vi: aw ai sw=2 +*/ |