rp

commit 98be34bb28d4b0598ad42f7ae07abb80cdd2984c
parent 3f7d589e713dd681813f0fe61211c9600d71e383
Author: parazyd <parazyd@dyne.org>
Date:   Sat,  3 Mar 2018 01:05:54 +0100

Generate a semi-random MIME boundary using rputil.

Diffstat:
M
bin/rpgenc
 | 
11
+++++------
M
bin/rpgsign
 | 
2
+-
M
util.c
 | 
43
+++++++++++++++++++++++++++++++++++++++----
M
util.h
 | 
3
+++

4 files changed, 48 insertions(+), 11 deletions(-)
diff --git a/bin/rpgenc b/bin/rpgenc
@@ -1,7 +1,6 @@
 #!/bin/sh
 
-boundary="FuNkAdEliC"
-encboundary="enc$boundary"
+boundary="$(rputil genmimebound)"
 
 email="$(cat)"
 
@@ -28,18 +27,18 @@ encr="$(echo "$emabody" | sed 's/$/\r/' | gpg -eaq --batch $to)"
 cat <<EOF
 $headers
 Content-Type: multipart/encrypted; protocol="application/pgp-encrypted";
-        boundary="$encboundary"
+        boundary="$boundary"
 
 
---$encboundary
+--$boundary
 Content-Type: application/pgp-encrypted
 
 Version: 1
 
---$encboundary
+--$boundary
 Content-Type: application/octet-stream
 
 $encr
 
---$encboundary--
+--$boundary--
 EOF
diff --git a/bin/rpgsign b/bin/rpgsign
@@ -1,6 +1,6 @@
 #!/bin/sh
 
-boundary="FuNkAdEliC"
+boundary="$(rputil genmimebound)"
 
 email="$(cat)"
 
diff --git a/util.c b/util.c
@@ -3,29 +3,61 @@
  * by parazyd
  */
 
+#include <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <time.h>
+#include <unistd.h>
 
 #include "arg.h"
 #include "ind.h"
 #include "util.h"
 
+char be[] =
+	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
+
 void utilusage(void) {
 	die("usage: %s [cmd]\n"
 		"   available commands:\n"
 		"\tgenmsgid: generates a Message-ID header\n", "rputil");
 }
 
+int randint(int max) {
+	unsigned int ret;
+	FILE *f;
+
+	f = fopen("/dev/urandom", "r");
+	fread(&ret, sizeof(ret), 1, f);
+	fclose(f);
+
+	return ret % max;
+}
+
+char *randstring(char *str, size_t size) {
+	if (size) {
+		size--;
+		for (size_t n = 0; n < size; n++) {
+			int key = randint(sizeof(be-1));
+			str[n] = be[key];
+		}
+		str[size] = '\0';
+	}
+	return str;
+}
+
 int genmsgid(void) {
-	int n;
 	char buf[15];
 	time_t now = time(0);
 	strftime(buf, 15, "%Y%m%d%H%M%S", localtime(&now));
-	srand(now); /* not secure ;) */
-	n = rand() % 9999;
-	printf("<%s.GA%d@fq>\n", buf, n);
+	printf("<%s.GA%d@fq>\n", buf, randint(9999));
+	return 0;
+}
+
+int genmimebound(void) {
+	char buf[5];
+	randstring(buf, sizeof(buf));
+	printf("%s-FuNkADeLiC\n", buf);
 	return 0;
 }
 
@@ -37,6 +69,9 @@ int utilmain(int argc, char *argv[]) {
 	if (!strncmp("genmsgid", argv[1], 8))
 		return genmsgid();
 
+	if (!strncmp("genmimebound", argv[1], 12))
+		return genmimebound();
+
 	utilusage();
 	return 1;
 }
diff --git a/util.h b/util.h
@@ -7,6 +7,9 @@
 #define __RPUTIL_H__
 
 int utilmain(int argc, char *argv[]);
+int randint(int max);
+char *randstring(char *str, size_t size);
 int genmsgid(void);
+int genmimebound(void);
 
 #endif