Add support for encoding version lists

share/dictionary.eap.sim

@@ -14,7 +14,7 @@ ATTRIBUTE	EAP-SIM-Res				3	octets
 ATTRIBUTE	EAP-SIM-Auts				4	octets
 ATTRIBUTE	EAP-SIM-Nonce-MT			7	octets
 ATTRIBUTE	EAP-SIM-Permanent-ID-Req		10	bool
-ATTRIBUTE	EAP-SIM-Mac				11	octets
+ATTRIBUTE	EAP-SIM-Mac				11	octets[20]
 ATTRIBUTE	EAP-SIM-Notification			12	short
 
 VALUE	EAP-SIM-Notification		General-Failure-After-Authentication 0

src/modules/rlm_eap/lib/sim/base.c

@@ -40,6 +40,50 @@ RCSID("$Id$")
 fr_dict_attr_t const *dict_sim_root;
 fr_dict_attr_t const *dict_aka_root;
 
+/** SIM AT on-the-wire format attribute sizes
+ *
+ * Holds the min/max sizes of all supported SIM AT attribute values as they
+ * would be found in a SIM AT packet.
+ *
+ * These sizes may be different than the sizes of INTERNAL formats, PRESENTATION
+ * formats and generic NETWORK formats.
+ */
+size_t const fr_sim_attr_sizes[FR_TYPE_MAX + 1][2] = {
+	[FR_TYPE_INVALID]		= {~0, 0},
+
+	[FR_TYPE_STRING]		= {0, ~0},
+	[FR_TYPE_OCTETS]		= {0, ~0},
+
+	[FR_TYPE_BOOL]			= {2, 2},
+	[FR_TYPE_UINT8]			= {1, 1},
+	[FR_TYPE_UINT16]		= {2, 2},
+	[FR_TYPE_UINT32]		= {4, 4},
+	[FR_TYPE_UINT64]		= {8, 8},
+
+	[FR_TYPE_TLV]			= {2, ~0},
+
+	[FR_TYPE_MAX]			= {~0, 0}	//!< Ensure array covers all types.
+};
+
+/** Return the on-the-wire length of an attribute value
+ *
+ * @param[in] vp to return the length of.
+ * @return the length of the attribute.
+ */
+size_t fr_sim_attr_len(VALUE_PAIR const *vp)
+{
+	switch (vp->vp_type) {
+	case FR_TYPE_VARIABLE_SIZE:
+		return vp->vp_length;
+
+	default:
+		return fr_radius_attr_sizes[vp->vp_type][0];
+
+	case FR_TYPE_STRUCTURAL:
+		if (!fr_cond_assert(0)) return 0;
+	}
+}
+
 /*
  * definitions changed to take a buffer for unknowns
  * as this is more thread safe.

src/modules/rlm_eap/lib/sim/decode.c

@@ -256,7 +256,7 @@ static int fr_sim_array_members(size_t *out, size_t len, fr_dict_attr_t const *d
 		break;
 
 	default:
-		element_len = dict_attr_sizes[da->type][0];
+		element_len = fr_sim_attr_sizes[da->type][0];
 		break;
 	}
 

src/modules/rlm_eap/lib/sim/encode.c

@@ -338,6 +338,13 @@ static ssize_t encode_value(uint8_t *out, size_t outlen,
 		*p++ = 0;	/* Reserved */
 		*p++ = 0;	/* Reserved */
 
+		if (vp->da->flags.length && (vp->vp_length != vp->da->flags.length)) {
+			fr_strerror_printf("%s: Attribute \"%s\" needs a value of exactly %zu bytes, "
+					   "but value was %zu bytes", __FUNCTION__,
+					   vp->da->name, (size_t)vp->da->flags.length, vp->vp_length);
+			return -1;
+		}
+
 		memcpy(p, vp->vp_octets, vp->vp_length);
 		p += vp->vp_length;
 
@@ -376,6 +383,13 @@ static ssize_t encode_value(uint8_t *out, size_t outlen,
 
 		if ((rounded_len + 2) > outlen) goto oos;
 
+		if (vp->da->flags.length && (vp->vp_length != vp->da->flags.length)) {
+			fr_strerror_printf("%s: Attribute \"%s\" needs a value of exactly %zu bytes, "
+					   "but value was %zu bytes", __FUNCTION__,
+					   vp->da->name, (size_t)vp->da->flags.length, vp->vp_length);
+			return -1;
+		}
+
 		memcpy(p, &actual_len, sizeof(actual_len));		/* Big endian real string length */
 		p += sizeof(actual_len);
 
@@ -444,6 +458,71 @@ static ssize_t encode_value(uint8_t *out, size_t outlen,
 	return len;
 }
 
+/** Encodes the data portion of an attribute
+ *
+ @verbatim
+	0                   1                   2                   3
+	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	| AT_VERSION_L..| Length        | Actual Version List Length    |
+	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	|  Supported Version 1          |  Supported Version 2          |
+	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	.                                                               .
+	.                                                               .
+	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	| Supported Version N           |     Padding                   |
+	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ @endverbatim
+ *
+ */
+static ssize_t encode_array(uint8_t *out, size_t outlen,
+			    fr_dict_attr_t const **tlv_stack, int depth,
+			    vp_cursor_t *cursor, void *encoder_ctx)
+{
+	uint8_t			*p = out, *end = p + outlen;
+	uint8_t			*value;
+	size_t			pad_len;
+	uint16_t		actual_len;
+	fr_dict_attr_t const	*da = tlv_stack[depth];
+
+	rad_assert(da->flags.array);
+
+	p += 2;
+	value = p;	/* Space for actual length */
+
+	/*
+	 *	Keep encoding as long as we have space to
+	 *	encode things.
+	 */
+	while (fr_sim_attr_sizes[da->type][0] <= ((size_t)(end - p))) {
+		VALUE_PAIR	*vp;
+		ssize_t		slen;
+
+		slen = encode_value(p, end - p, tlv_stack, depth, cursor, encoder_ctx);
+		if (slen < 0) return slen;
+
+		p += slen;
+
+		vp = fr_pair_cursor_current(cursor);
+		if (!vp || (vp->da != da)) break;		/* Stop if we have an attribute of a different type */
+	}
+
+	actual_len = htons((p - value) & UINT16_MAX);	/* Length of the elements we encoded */
+	memcpy(out, &actual_len, sizeof(actual_len));
+
+	/*
+	 *	Pad value a multiple of 4
+	 */
+	pad_len = (((p - value) + 3) & ~3) - (p - value);
+	if (pad_len) {
+		memset(p, 0, pad_len);
+		p += pad_len;
+	}
+
+	return p - out;
+}
+
 /** Encode an RFC format attribute header
  *
  * This could be a standard attribute, or a TLV data type.
@@ -487,9 +566,13 @@ static ssize_t encode_rfc_hdr(uint8_t *out, size_t outlen, fr_dict_attr_t const
 	 *	length.
 	 */
 	da = tlv_stack[depth];
-	slen = encode_value(out + 2, outlen - 2, tlv_stack, depth, cursor, encoder_ctx);
-	if (slen <= 0) return slen;
 
+	if (da->flags.array) {
+		slen = encode_array(out + 2, outlen - 2, tlv_stack, depth, cursor, encoder_ctx);
+	} else {
+		slen = encode_value(out + 2, outlen - 2, tlv_stack, depth, cursor, encoder_ctx);
+	}
+	if (slen <= 0) return slen;
 	/*
 	 *	Round attr + len + data length out to a multiple
 	 *	of four, and setup the attribute header and
@@ -668,10 +751,11 @@ ssize_t fr_sim_encode_pair(uint8_t *out, size_t outlen, vp_cursor_t *cursor, voi
 	 *	Fast path for the common case.
 	 */
 	if ((vp->da->parent == packet_ctx->root) && !vp->da->flags.concat && (vp->vp_type != FR_TYPE_TLV)) {
-		tlv_stack[0] = vp->da;
-		tlv_stack[1] = NULL;
+		tlv_stack[0] = packet_ctx->root;
+		tlv_stack[1] = vp->da;
+		tlv_stack[2] = NULL;
 		FR_PROTO_STACK_PRINT(tlv_stack, 0);
-		return encode_rfc_hdr(out, attr_len, tlv_stack, 0, cursor, encoder_ctx);
+		return encode_rfc_hdr(out, attr_len, tlv_stack, 1, cursor, encoder_ctx);
 	}
 
 	/*
@@ -772,8 +856,8 @@ ssize_t fr_sim_encode(REQUEST *request, fr_dict_attr_t const *parent, uint8_t ty
 		MEM(buff = talloc_array(eap_packet, uint8_t, 3));
 
 		buff[0] = subtype;	/* SIM or AKA subtype */
-		buff[1] = 0;		/* Reserved */
-		buff[2] = 0;		/* Reserved */
+		buff[1] = 0;		/* Reserved (0) */
+		buff[2] = 0;		/* Reserved (1) */
 
 		eap_packet->type.length = 3;
 		eap_packet->type.data = buff;
@@ -786,9 +870,9 @@ ssize_t fr_sim_encode(REQUEST *request, fr_dict_attr_t const *parent, uint8_t ty
 	end = p + talloc_array_length(p);
 	if (do_hmac) end -= SIM_CALC_MAC_SIZE;
 
-	*p++ = subtype;			/* Subtype  (1) */
-	*p++ = 0;			/* Reserved */
-	*p++ = 0;			/* Reserved */
+	*p++ = subtype;			/* Subtype */
+	*p++ = 0;			/* Reserved (0) */
+	*p++ = 0;			/* Reserved (1) */
 
 	/*
 	 *	Encode all the things...

src/modules/rlm_eap/lib/sim/sim_proto.h

@@ -163,6 +163,7 @@ typedef struct {
 
 typedef struct _eap_session eap_session_t;
 
+extern size_t const fr_sim_attr_sizes[FR_TYPE_MAX + 1][2];
 extern fr_dict_attr_t const *dict_sim_root;
 extern fr_dict_attr_t const *dict_aka_root;
 
@@ -186,6 +187,8 @@ ssize_t		fr_sim_encode(REQUEST *request, fr_dict_attr_t const *parent, uint8_t t
 /*
  *	base.c
  */
+size_t		fr_sim_attr_len(VALUE_PAIR const *vp);
+
 char const	*fr_sim_session_to_name(char *out, size_t outlen, eap_sim_client_states_t state);
 
 int		fr_sim_global_init(void);

src/tests/unit/eap-sim.txt

@@ -78,3 +78,16 @@ data 82 05 00 00 3f b8 34 1f f8 26 e0 4d 4a f3 f9 61 3c a9 84 26 0d 01 00 00 82
 
 decode-pair.tp_decode_sim -
 data EAP-SIM-Next-Pseudonym = "testing123", EAP-SIM-Any-ID-Req = yes, EAP-SIM-Counter-Too-Small = yes
+
+# Array (one element)
+encode-pair.tp_encode_sim EAP-SIM-Version-List = 1
+data 0f 02 00 02 00 01 00 00
+
+# Array (multiple elements, with padding)
+encode-pair.tp_encode_sim EAP-SIM-Version-List = 1, EAP-SIM-Version-List = 2, EAP-SIM-Version-List = 3
+data 0f 03 00 06 00 01 00 02 00 03 00 00
+
+# Array (multiple elements, with no padding)
+encode-pair.tp_encode_sim EAP-SIM-Version-List = 1, EAP-SIM-Version-List = 2, EAP-SIM-Version-List = 3, EAP-SIM-Version-List = 4
+data 0f 03 00 08 00 01 00 02 00 03 00 04
+