CTM email tools.

Reviewed by:	phk
Submitted by:	Stephen McKay <syssgm@devetir.qld.gov.au>

2 files changed, 331 insertions, 0 deletions

diff --git a/usr.sbin/ctm/ctm_smail/Makefile b/usr.sbin/ctm/ctm_smail/Makefile
new file mode 100644
index 0000000..085899c
--- /dev/null
+++ b/usr.sbin/ctm/ctm_smail/Makefile
@@ -0,0 +1,7 @@
+PROG=           ctm_smail
+SRCS=           ctm_smail.c error.c
+NOMAN=          1
+CFLAGS+=        -Wall -g -I${.CURDIR}/../ctm_rmail
+
+.include <bsd.prog.mk>
+.PATH: ${.CURDIR}/../ctm_rmail
diff --git a/usr.sbin/ctm/ctm_smail/ctm_smail.c b/usr.sbin/ctm/ctm_smail/ctm_smail.c
new file mode 100644
index 0000000..b0379a2
--- /dev/null
+++ b/usr.sbin/ctm/ctm_smail/ctm_smail.c
@@ -0,0 +1,324 @@
+/*
+ * Send a compressed CTM delta to a recipient mailing list by encoding it 
+ * in safe ASCII characters, in mailer-friendly chunks, and passing it
+ * to sendmail.  The encoding is almost the same as MIME BASE64, and is
+ * protected by a simple checksum.
+ *
+ * Author: Stephen McKay
+ *
+ * NOTICE: This is free software.  I hope you get some use from this program.  
+ * In return you should think about all the nice people who give away software. 
+ * Maybe you should write some free software too.  
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <paths.h>
+#include "error.h"
+#include "options.h"
+
+#define DEF_MAX_MSG	64000	/* Default maximum mail msg minus headers. */
+
+#define LINE_LENGTH	76	/* Chars per encode line. Divisible by 4. */
+
+void chop_and_send(char *delta, off_t ctm_size, long max_msg_size,
+	char *mail_alias);
+unsigned encode_body(FILE *sm_fp, FILE *delta_fp, long msg_size);
+void write_header(FILE *sfp, char *mail_alias, char *delta, int pce,
+	int npieces);
+void write_trailer(FILE *sfp, unsigned sum);
+void apologise(char *delta, off_t ctm_size, long max_ctm_size,
+	char *mail_alias);
+FILE *open_sendmail(void);
+int close_sendmail(FILE *fp);
+
+
+main(int argc, char **argv)
+    {
+    char *delta_file;
+    char *mail_alias;
+    long max_msg_size = DEF_MAX_MSG;
+    long max_ctm_size = 0;
+    char *log_file = NULL;
+    struct stat sb;
+
+    err_prog_name(argv[0]);
+
+    OPTIONS("[-l log] [-m maxmsgsize] [-c maxctmsize] ctm-delta mail-alias")
+	NUMBER('m', max_msg_size)
+	NUMBER('c', max_ctm_size)
+	STRING('l', log_file)
+    ENDOPTS
+
+    if (argc != 3)
+	usage();
+
+    if (log_file != NULL)
+	err_set_log(log_file);
+
+    delta_file = argv[1];
+    mail_alias = argv[2];
+
+    if (stat(delta_file, &sb) < 0)
+	{
+	err("%s: %s", delta_file, strerror(errno));
+	exit(1);
+	}
+    
+    if (max_ctm_size != 0 && sb.st_size > max_ctm_size)
+	apologise(delta_file, sb.st_size, max_ctm_size, mail_alias);
+    else
+	chop_and_send(delta_file, sb.st_size, max_msg_size, mail_alias);
+
+    return 0;
+    }
+
+
+/*
+ * Carve our CTM delta into pieces, encode them, and send them.
+ */
+void
+chop_and_send(char *delta, off_t ctm_size, long max_msg_size, char *mail_alias)
+    {
+    int npieces;
+    long msg_size;
+    long exp_size;
+    int pce;
+    FILE *sfp;
+    FILE *dfp;
+    unsigned sum;
+
+#define howmany(x,y)	(((x)+((y)-1))/(y))
+
+    /*
+     * Work out how many pieces we need, bearing in mind that each piece
+     * grows by 4/3 when encoded.  We count the newlines too, but ignore
+     * all mail headers and piece headers.  They are a "small" (almost
+     * constant) per message overhead that we make the user worry about. :-)
+     */
+    exp_size = ctm_size * 4 / 3;
+    exp_size += howmany(exp_size, LINE_LENGTH);
+    npieces = howmany(exp_size, max_msg_size);
+    msg_size = howmany(ctm_size, npieces);
+
+#undef howmany
+
+    if ((dfp = fopen(delta, "r")) == NULL)
+	{
+	err("cannot open '%s' for reading.", delta);
+	exit(1);
+	}
+
+    for (pce = 1; pce <= npieces; pce++)
+	{
+	sfp = open_sendmail();
+	if (sfp == NULL)
+	    exit(1);
+	write_header(sfp, mail_alias, delta, pce, npieces);
+	sum = encode_body(sfp, dfp, msg_size);
+	write_trailer(sfp, sum);
+	if (!close_sendmail(sfp))
+	    exit(1);
+	err("%s %d/%d sent to %s", delta, pce, npieces, mail_alias);
+	}
+
+    fclose(dfp);
+    }
+
+
+/*
+ * MIME BASE64 encode table.
+ */
+static char to_b64[0x40] =
+    "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+/*
+ * This cheap plastic checksum effectively rotates our checksum-so-far
+ * left one, then adds the character.  We only want 16 bits of it, and
+ * don't care what happens to the rest.  It ain't much, but it's small.
+ */
+#define add_ck(sum,x)	\
+    ((sum) += ((x)&0xff) + (sum) + (((sum)&0x8000) ? 1 : 0))
+
+/*
+ * Encode the body.  Use an encoding almost the same as MIME BASE64.
+ *
+ * Characters are read from delta_fp and encoded characters are written
+ * to sm_fp.  At most 'msg_size' characters should be read from delta_fp.
+ *
+ * The body consists of lines of up to LINE_LENGTH characters.  Each group
+ * of 4 characters encodes 3 input characters.  Each output character encodes
+ * 6 bits.  Thus 64 different characters are needed in this representation.
+ */
+unsigned
+encode_body(FILE *sm_fp, FILE *delta_fp, long msg_size)
+    {
+    unsigned short cksum = 0xffff;
+    unsigned char *ip;
+    char *op;
+    int want, n, i;
+    unsigned char inbuf[LINE_LENGTH*3/4];
+    char outbuf[LINE_LENGTH+1];
+
+    /*
+     * Round up to the nearest line boundary, for the tiniest of gains,
+     * and lots of neatness. :-)
+     */
+    msg_size += (LINE_LENGTH*3/4) - 1;
+    msg_size -= msg_size % (LINE_LENGTH*3/4);
+
+    while (msg_size > 0)
+	{
+	want = (msg_size < sizeof(inbuf)) ? msg_size : sizeof(inbuf);
+	if ((n = fread(inbuf, sizeof(char), want, delta_fp)) == 0)
+	    break;
+	msg_size -= n;
+
+	for (i = 0; i < n; i++)
+	    add_ck(cksum, inbuf[i]);
+
+	/*
+	 * Produce a line of encoded data.  Every line length will be a
+	 * multiple of 4, except for, perhaps, the last line.
+	 */
+	ip = inbuf;
+	op = outbuf;
+	while (n >= 3)
+	    {
+	    *op++ = to_b64[ip[0] >> 2];
+	    *op++ = to_b64[(ip[0] << 4 & 0x3f) | ip[1] >> 4];
+	    *op++ = to_b64[(ip[1] << 2 & 0x3f) | ip[2] >> 6];
+	    *op++ = to_b64[ip[2] & 0x3f];
+	    ip += 3;
+	    n -= 3;
+	    }
+	if (n > 0)
+	    {
+	    *op++ = to_b64[ip[0] >> 2];
+	    *op++ = to_b64[(ip[0] << 4 & 0x3f) | ip[1] >> 4];
+	    if (n >= 2)
+		*op++ = to_b64[ip[1] << 2 & 0x3f];
+	    }
+	*op++ = '\n';
+	fwrite(outbuf, sizeof(char), op - outbuf, sm_fp);
+	}
+
+    if (ferror(delta_fp))
+	{
+	err("error reading input file.");
+	exit(1);
+	}
+
+    if (ferror(sm_fp))
+	{
+	err("error writing to sendmail");
+	exit(1);
+	}
+
+    return cksum;
+    }
+
+
+/*
+ * Write the mail header and data header.
+ */
+void
+write_header(FILE *sfp, char *mail_alias, char *delta, int pce, int npieces)
+    {
+    char *sn;
+
+    if ((sn = strrchr(delta, '/')) == NULL)
+	sn = delta;
+    else
+	sn++;
+
+    fprintf(sfp, "From: %s-owner\n", mail_alias);
+    fprintf(sfp, "To: %s\n", mail_alias);
+    fprintf(sfp, "Subject: ctm-mail %s %d/%d\n\n", sn, pce, npieces);
+
+    fprintf(sfp, "CTM_MAIL BEGIN %s %d %d\n", sn, pce, npieces);
+    }
+
+
+/*
+ * Write the data trailer.
+ */
+void
+write_trailer(FILE *sfp, unsigned sum)
+    {
+    fprintf(sfp, "CTM_MAIL END %ld\n", (long)sum);
+    }
+
+
+/*
+ * We're terribly sorry, but the delta is too big to send.
+ */
+void
+apologise(char *delta, off_t ctm_size, long max_ctm_size, char *mail_alias)
+    {
+    FILE *sfp;
+    char *sn;
+
+    sfp = open_sendmail();
+    if (sfp == NULL)
+	exit(1);
+
+    if ((sn = strrchr(delta, '/')) == NULL)
+	sn = delta;
+    else
+	sn++;
+
+    fprintf(sfp, "From: %s-owner\n", mail_alias);
+    fprintf(sfp, "To: %s\n", mail_alias);
+    fprintf(sfp, "Subject: ctm-notice %s\n\n", sn);
+
+    fprintf(sfp, "%s is %ld bytes.  The limit is %ld bytes.\n\n", sn,
+	(long)ctm_size, max_ctm_size);
+    fprintf(sfp, "You can retrieve this delta via ftpmail, or your good mate at the university.\n");
+
+    if (!close_sendmail(sfp))
+	exit(1);
+    }
+
+
+/*
+ * Start a pipe to sendmail.  Sendmail will decode the destination
+ * from the message contents.
+ */
+FILE *
+open_sendmail()
+    {
+    FILE *fp;
+    char buf[100];
+
+    sprintf(buf, "%s -t", _PATH_SENDMAIL);
+    if ((fp = popen(buf, "w")) == NULL)
+	err("cannot start sendmail");
+    return fp;
+    }
+
+
+/*
+ * Close a pipe to sendmail.  Sendmail will then do its bit.
+ * Return 1 on success, 0 on failure.
+ */
+int
+close_sendmail(FILE *fp)
+    {
+    int status;
+
+    fflush(fp);
+    if (ferror(fp))
+	{
+	err("error writing to sendmail");
+	return 0;
+	}
+
+    if ((status = pclose(fp)) != 0)
+	err("sendmail failed with status %d", status);
+
+    return (status == 0);
+    }