From 5476ce31d628a871bc88f9ef018cbebc05b3aa85 Mon Sep 17 00:00:00 2001
From: Jeff Connelly <shellreef+git@gmail.com>
Date: Thu, 15 May 2008 13:16:05 -0700
Subject: [PATCH] Output packaging works.

---
 libotp.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++--
 libotp.h |  3 +++
 try.c    |  6 +++++-
 3 files changed, 54 insertions(+), 3 deletions(-)

diff --git a/libotp.c b/libotp.c
index 5f4fb73..804b2ba 100644
--- a/libotp.c
+++ b/libotp.c
@@ -433,7 +433,51 @@ unsigned int otp_decrypt(char *input, char **out)
     return length;
 }
 
-char *otp_encrypt(char *input)
+/** Encrypt and package a message. 
+ *
+ * @return Encrypted, packaged message. Caller must free.
+ */
+char *otp_encrypt(char *input, unsigned int length, char *to)
 {
-    return NULL;
+    PAD *p;
+    char *out;
+    unsigned int out_length;
+    unsigned long offset;
+    char *b64_data;
+    
+    p = find_pad(to);
+    if (!p) {
+        fprintf(stderr, "otp_encrypt: no such pad %s\n", to);
+        exit(EX_DATAERR);
+    }
+
+    /* Packaged messages are base64'd encoded so they take
+     * 4/3 as much space, plus a fixed amount for markers, plus
+     * up to OFFSET_SIZE bytes for the offset. To avoid possible
+     * rounding errors in calculating the size, just multiply by 2.
+     * This overestimates and should be more than enough space.
+     */
+    out_length = strlen(MARKER_BEGIN) + 1 + OFFSET_SIZE + 1 + 
+        1 + length * 2 + 1 + strlen(MARKER_END) + 1;
+    out = malloc(out_length);
+    if (!out) {
+        perror("malloc otp_decrypt output");
+        exit(EX_DATAERR);
+    }
+
+    /* Use current offset. */
+    offset = read_offset(p);
+
+    b64_data = "(todo)";
+
+    snprintf(out, out_length, "%s%d,%s,\n"
+            "%s\n"
+            "%s\n",
+            MARKER_BEGIN,
+            offset,
+            to,
+            b64_data,
+            MARKER_END);
+
+    return out;
 }
diff --git a/libotp.h b/libotp.h
index 69a49ad..72720a8 100644
--- a/libotp.h
+++ b/libotp.h
@@ -33,6 +33,7 @@ typedef struct _MESSAGE {
     char *cipher_text;
 } MESSAGE;
 
+void load_config(char *config_filename);
 void show_pads();
 FILE *open_offset_file(PAD *p, char *mode);
 unsigned long read_offset(PAD *p);
@@ -41,4 +42,6 @@ void load_pad(char *local_filename, char *pad_name);
 void free_pads();
 MESSAGE *unpackage(char *input);
 void free_message(MESSAGE *);
+char *otp_encrypt(char *input, unsigned int length, char *to);
 unsigned int otp_decrypt(char *input, char **out);
+
diff --git a/try.c b/try.c
index e72cff5..e8d172d 100644
--- a/try.c
+++ b/try.c
@@ -6,6 +6,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include "libotp.h"
 
 extern PAD *pads;
@@ -15,6 +16,7 @@ int main()
     char *o;
 
     load_config("otp.conf");
+    show_pads();
 
     printf("offset=%ld\n", read_offset(pads));
     write_offset(pads, 1213475);
@@ -32,7 +34,9 @@ int main()
     puts(o);
     free(o);
 
-    show_pads();
+    o = otp_encrypt("hello world", strlen("hello world"), "dc");
+    printf("encrypt = %s\n", o);
+
     free_pads();
 
     return 0;
-- 
2.11.4.GIT