add asn1_u24_to_bitstring()

Sometimes we have a native uint32_t, but we don't want to encode
it to a 4-byte long ASN1 BITSTRING, but rather to one that is only
24 bits.

2 files changed, 8 insertions, 0 deletions

diff --git a/src/asn1helpers.c b/src/asn1helpers.c
index 3082ddc..3225223 100644
--- a/src/asn1helpers.c
+++ b/src/asn1helpers.c
@@ -31,6 +31,13 @@ void asn1_u32_to_bitstring(BIT_STRING_t *bitstr, uint32_t *in)
 	bitstr->bits_unused = 0;
 }
 
+void asn1_u24_to_bitstring(BIT_STRING_t *bitstr, uint32_t *in)
+{
+	bitstr->buf = (uint8_t *) in;
+	bitstr->size = 24/8;
+	bitstr->bits_unused = 0;
+}
+
 
 int asn1_strncpy(char *out, const OCTET_STRING_t *in, size_t n)
 {
diff --git a/src/asn1helpers.h b/src/asn1helpers.h
index 75b00e2..17d0d89 100644
--- a/src/asn1helpers.h
+++ b/src/asn1helpers.h
@@ -6,6 +6,7 @@
 #include "OCTET_STRING.h"
 
 void asn1_u32_to_bitstring(BIT_STRING_t *bitstr, uint32_t *in);
+void asn1_u24_to_bitstring(BIT_STRING_t *bitstr, uint32_t *in);
 int asn1_strncpy(char *out, const OCTET_STRING_t *in, size_t n);
 uint16_t asn1str_to_u16(const OCTET_STRING_t *in);
 uint8_t asn1str_to_u8(const OCTET_STRING_t *in);