1 files changed, 49 insertions, 0 deletions
diff --git a/src/lib-mail/quoted-printable.c b/src/lib-mail/quoted-printable.c
new file mode 100644
index 0000000..9bfbe35
--- /dev/null
+++ b/src/lib-mail/quoted-printable.c
@@ -0,0 +1,49 @@
+/* Copyright (c) 2002-2018 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "buffer.h"
+#include "hex-binary.h"
+#include "quoted-printable.h"
+
+int quoted_printable_q_decode(const unsigned char *src, size_t src_size,
+			      buffer_t *dest)
+{
+	char hexbuf[3];
+	size_t src_pos, next;
+	bool errors = FALSE;
+
+	hexbuf[2] = '\0';
+
+	next = 0;
+	for (src_pos = 0; src_pos < src_size; src_pos++) {
+		if (src[src_pos] != '_' && src[src_pos] != '=')
+			continue;
+
+		buffer_append(dest, src + next, src_pos - next);
+		next = src_pos;
+
+		if (src[src_pos] == '_') {
+			buffer_append_c(dest, ' ');
+			next++;
+			continue;
+		}
+
+		if (src_pos+2 >= src_size)
+			break;
+
+		/* =<hex> */
+		hexbuf[0] = src[src_pos+1];
+		hexbuf[1] = src[src_pos+2];
+
+		if (hex_to_binary(hexbuf, dest) == 0) {
+			src_pos += 2;
+			next = src_pos+1;
+		} else {
+			/* non-hex data, show as-is */
+			errors = TRUE;
+			next = src_pos;
+		}
+	}
+	buffer_append(dest, src + next, src_size - next);
+	return errors ? -1 : 0;
+}