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Diffstat (limited to 'src/global/mail_copy.c')
| -rw-r--r-- | src/global/mail_copy.c | 315 |
1 files changed, 315 insertions, 0 deletions
diff --git a/src/global/mail_copy.c b/src/global/mail_copy.c new file mode 100644 index 0000000..7c60370 --- /dev/null +++ b/src/global/mail_copy.c @@ -0,0 +1,315 @@ +/*++ +/* NAME +/* mail_copy 3 +/* SUMMARY +/* copy message with extreme prejudice +/* SYNOPSIS +/* #include <mail_copy.h> +/* +/* int mail_copy(sender, orig_to, delivered, src, dst, flags, eol, why) +/* const char *sender; +/* const char *orig_to; +/* const char *delivered; +/* VSTREAM *src; +/* VSTREAM *dst; +/* int flags; +/* const char *eol; +/* DSN_BUF *why; +/* DESCRIPTION +/* mail_copy() copies a mail message from record stream to stream-lf +/* stream, and attempts to detect all possible I/O errors. +/* +/* Arguments: +/* .IP sender +/* The sender envelope address. +/* .IP delivered +/* Null pointer or delivered-to: header address. +/* .IP src +/* The source record stream, positioned at the beginning of the +/* message contents. +/* .IP dst +/* The destination byte stream (in stream-lf format). If the message +/* ends in an incomplete line, a newline character is appended to +/* the output. +/* .IP flags +/* The binary OR of zero or more of the following: +/* .RS +/* .IP MAIL_COPY_QUOTE +/* Prepend a `>' character to lines beginning with `From '. +/* .IP MAIL_COPY_DOT +/* Prepend a `.' character to lines beginning with `.'. +/* .IP MAIL_COPY_TOFILE +/* On systems that support this, use fsync() to flush the +/* data to stable storage, and truncate the destination +/* file to its original length in case of problems. +/* .IP MAIL_COPY_FROM +/* Prepend a UNIX-style From_ line to the message. +/* .IP MAIL_COPY_BLANK +/* Append an empty line to the end of the message. +/* .IP MAIL_COPY_DELIVERED +/* Prepend a Delivered-To: header with the name of the +/* \fIdelivered\fR attribute. +/* The address is quoted according to RFC822 rules. +/* .IP MAIL_COPY_ORIG_RCPT +/* Prepend an X-Original-To: header with the original +/* envelope recipient address. This is a NOOP with +/* var_enable_orcpt === 0. +/* .IP MAIL_COPY_RETURN_PATH +/* Prepend a Return-Path: header with the value of the +/* \fIsender\fR attribute. +/* .RE +/* The manifest constant MAIL_COPY_MBOX is a convenient shorthand for +/* all MAIL_COPY_XXX options that are appropriate for mailbox delivery. +/* Use MAIL_COPY_NONE to copy a message without any options enabled. +/* .IP eol +/* Record delimiter, for example, LF or CF LF. +/* .IP why +/* A null pointer, or storage for the reason of failure in +/* the form of a DSN detail code plus free text. +/* DIAGNOSTICS +/* A non-zero result means the operation failed. Warnings: corrupt +/* message file. A corrupt message is marked as corrupt. +/* +/* The result is the bit-wise OR of zero or more of the following: +/* .IP MAIL_COPY_STAT_CORRUPT +/* The queue file is marked as corrupt. +/* .IP MAIL_COPY_STAT_READ +/* A read error was detected; errno specifies the nature of the problem. +/* .IP MAIL_COPY_STAT_WRITE +/* A write error was detected; errno specifies the nature of the problem. +/* SEE ALSO +/* mark_corrupt(3), mark queue file as corrupted. +/* 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 +/* +/* Wietse Venema +/* Google, Inc. +/* 111 8th Avenue +/* New York, NY 10011, USA +/*--*/ + +/* System library. */ + +#include <sys_defs.h> +#include <sys/stat.h> +#include <string.h> +#include <unistd.h> +#include <time.h> +#include <errno.h> + +/* Utility library. */ + +#include <msg.h> +#include <htable.h> +#include <vstream.h> +#include <vstring.h> +#include <vstring_vstream.h> +#include <stringops.h> +#include <iostuff.h> +#include <warn_stat.h> + +/* Global library. */ + +#include "quote_822_local.h" +#include "record.h" +#include "rec_type.h" +#include "mail_queue.h" +#include "mail_addr.h" +#include "mark_corrupt.h" +#include "mail_params.h" +#include "mail_copy.h" +#include "mbox_open.h" +#include "dsn_buf.h" +#include "sys_exits.h" + +/* mail_copy - copy message with extreme prejudice */ + +int mail_copy(const char *sender, + const char *orig_rcpt, + const char *delivered, + VSTREAM *src, VSTREAM *dst, + int flags, const char *eol, DSN_BUF *why) +{ + const char *myname = "mail_copy"; + VSTRING *buf; + char *bp; + off_t orig_length; + int read_error; + int write_error; + int corrupt_error = 0; + time_t now; + int type; + int prev_type; + struct stat st; + off_t size_limit; + + /* + * Workaround 20090114. This will hopefully get someone's attention. The + * problem with file_size_limit < message_size_limit is that mail will be + * delivered again and again until someone removes it from the queue by + * hand, because Postfix cannot mark a recipient record as "completed". + */ + if (fstat(vstream_fileno(src), &st) < 0) + msg_fatal("fstat: %m"); + if ((size_limit = get_file_limit()) < st.st_size) + msg_panic("file size limit %lu < message size %lu. This " + "causes large messages to be delivered repeatedly " + "after they were submitted with \"sendmail -t\" " + "or after recipients were added with the Milter " + "SMFIR_ADDRCPT request", + (unsigned long) size_limit, + (unsigned long) st.st_size); + + /* + * Initialize. + */ +#ifndef NO_TRUNCATE + if ((flags & MAIL_COPY_TOFILE) != 0) + if ((orig_length = vstream_fseek(dst, (off_t) 0, SEEK_END)) < 0) + msg_fatal("seek file %s: %m", VSTREAM_PATH(dst)); +#endif + buf = vstring_alloc(100); + + /* + * Prepend a bunch of headers to the message. + */ + if (flags & (MAIL_COPY_FROM | MAIL_COPY_RETURN_PATH)) { + if (sender == 0) + msg_panic("%s: null sender", myname); + quote_822_local(buf, sender); + if (flags & MAIL_COPY_FROM) { + time(&now); + vstream_fprintf(dst, "From %s %.24s%s", *sender == 0 ? + MAIL_ADDR_MAIL_DAEMON : vstring_str(buf), + asctime(localtime(&now)), eol); + } + if (flags & MAIL_COPY_RETURN_PATH) { + vstream_fprintf(dst, "Return-Path: <%s>%s", + *sender ? vstring_str(buf) : "", eol); + } + } + if (flags & MAIL_COPY_ORIG_RCPT) { + if (orig_rcpt == 0) + msg_panic("%s: null orig_rcpt", myname); + + /* + * An empty original recipient record almost certainly means that + * original recipient processing was disabled. + */ + if (var_enable_orcpt && *orig_rcpt) { + quote_822_local(buf, orig_rcpt); + vstream_fprintf(dst, "X-Original-To: %s%s", vstring_str(buf), eol); + } + } + if (flags & MAIL_COPY_DELIVERED) { + if (delivered == 0) + msg_panic("%s: null delivered", myname); + quote_822_local(buf, delivered); + vstream_fprintf(dst, "Delivered-To: %s%s", vstring_str(buf), eol); + } + + /* + * Copy the message. Escape lines that could be confused with the ugly + * From_ line. Make sure that there is a blank line at the end of the + * message so that the next ugly From_ can be found by mail reading + * software. + * + * XXX Rely on the front-end services to enforce record size limits. + */ +#define VSTREAM_FWRITE_BUF(s,b) \ + vstream_fwrite((s),vstring_str(b),VSTRING_LEN(b)) + + prev_type = REC_TYPE_NORM; + while ((type = rec_get(src, buf, 0)) > 0) { + if (type != REC_TYPE_NORM && type != REC_TYPE_CONT) + break; + bp = vstring_str(buf); + if (prev_type == REC_TYPE_NORM) { + if ((flags & MAIL_COPY_QUOTE) && *bp == 'F' && !strncmp(bp, "From ", 5)) + VSTREAM_PUTC('>', dst); + if ((flags & MAIL_COPY_DOT) && *bp == '.') + VSTREAM_PUTC('.', dst); + } + if (VSTRING_LEN(buf) && VSTREAM_FWRITE_BUF(dst, buf) != VSTRING_LEN(buf)) + break; + if (type == REC_TYPE_NORM && vstream_fputs(eol, dst) == VSTREAM_EOF) + break; + prev_type = type; + } + if (vstream_ferror(dst) == 0) { + if (var_fault_inj_code == 1) + type = 0; + if (type != REC_TYPE_XTRA) { + /* XXX Where is the queue ID? */ + msg_warn("bad record type: %d in message content", type); + corrupt_error = mark_corrupt(src); + } + if (prev_type != REC_TYPE_NORM) + vstream_fputs(eol, dst); + if (flags & MAIL_COPY_BLANK) + vstream_fputs(eol, dst); + } + vstring_free(buf); + + /* + * Make sure we read and wrote all. Truncate the file to its original + * length when the delivery failed. POSIX does not require ftruncate(), + * so we may have a portability problem. Note that fclose() may fail even + * while fflush and fsync() succeed. Think of remote file systems such as + * AFS that copy the file back to the server upon close. Oh well, no + * point optimizing the error case. XXX On systems that use flock() + * locking, we must truncate the file before closing it (and losing + * the exclusive lock). + */ + read_error = vstream_ferror(src); + write_error = vstream_fflush(dst); +#ifdef HAS_FSYNC + if ((flags & MAIL_COPY_TOFILE) != 0) + write_error |= fsync(vstream_fileno(dst)); +#endif + if (var_fault_inj_code == 2) { + read_error = 1; + errno = ENOENT; + } + if (var_fault_inj_code == 3) { + write_error = 1; + errno = ENOENT; + } +#ifndef NO_TRUNCATE + if ((flags & MAIL_COPY_TOFILE) != 0) + if (corrupt_error || read_error || write_error) + /* Complain about ignored "undo" errors? So sue me. */ + (void) ftruncate(vstream_fileno(dst), orig_length); +#endif + write_error |= vstream_fclose(dst); + + /* + * Return the optional verbose error description. + */ +#define TRY_AGAIN_ERROR(errno) \ + (errno == EAGAIN || errno == ESTALE) + + if (why && read_error) + dsb_unix(why, TRY_AGAIN_ERROR(errno) ? "4.3.0" : "5.3.0", + sys_exits_detail(EX_IOERR)->text, + "error reading message: %m"); + if (why && write_error) + dsb_unix(why, mbox_dsn(errno, "5.3.0"), + sys_exits_detail(EX_IOERR)->text, + "error writing message: %m"); + + /* + * Use flag+errno description when the optional verbose description is + * not desired. + */ + return ((corrupt_error ? MAIL_COPY_STAT_CORRUPT : 0) + | (read_error ? MAIL_COPY_STAT_READ : 0) + | (write_error ? MAIL_COPY_STAT_WRITE : 0)); +} |