forked from osmocom/wireshark
wlan: clean up some tests.
It's clearer to say
if (A) {
if (B) {
do this;
} else {
do that;
}
}
than to say
if (A && B) {
do this;
} else if (A && !B) {
do that;
}
(cherry picked from commit baee4a41c7)
This commit is contained in:
Guy Harris
parent
3d62a28f06
commit
be38cd2edb
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@ -25308,77 +25308,79 @@ dissect_ieee80211_common(tvbuff_t *tvb, packet_info *pinfo,
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case DATA_FRAME:
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hdr_len = (FCF_ADDR_SELECTOR(fcf) == DATA_ADDR_T4) ? DATA_LONG_HDR_LEN : DATA_SHORT_HDR_LEN;
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if ((option_flags & IEEE80211_COMMON_OPT_NORMAL_QOS) && DATA_FRAME_IS_QOS(frame_type_subtype)) {
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/* QoS frame */
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qosoff = hdr_len;
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hdr_len += 2; /* Include the QoS field in the header length */
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if (option_flags & IEEE80211_COMMON_OPT_NORMAL_QOS) {
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if (DATA_FRAME_IS_QOS(frame_type_subtype)) {
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/* QoS frame */
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qosoff = hdr_len;
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hdr_len += 2; /* Include the QoS field in the header length */
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if (HAS_HT_CONTROL(FCF_FLAGS(fcf))) {
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/*
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* QoS data frames with the Order bit set have an HT Control field;
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* see 8.2.4.1.10 "Order field". If they're not HT frames, they
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* should never have the Order bit set.
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*/
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hdr_len += 4;
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htc_len = 4;
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}
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/*
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* Does it look as if we have a mesh header?
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* Look at the Mesh Control subfield of the QoS field and at the
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* purported mesh flag fields.
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*/
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qos_control = tvb_get_letohs(tvb, qosoff);
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if (tvb_bytes_exist(tvb, hdr_len, 1)) {
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meshoff = hdr_len;
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mesh_flags = tvb_get_guint8(tvb, meshoff);
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if (has_mesh_control(fcf, qos_control, mesh_flags)) {
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/* Yes, add the length of that in as well. */
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meshctl_len = find_mesh_control_length(mesh_flags);
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hdr_len += meshctl_len;
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if (HAS_HT_CONTROL(FCF_FLAGS(fcf))) {
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/*
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* QoS data frames with the Order bit set have an HT Control field;
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* see 8.2.4.1.10 "Order field". If they're not HT frames, they
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* should never have the Order bit set.
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*/
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hdr_len += 4;
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htc_len = 4;
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}
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}
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} else if ((option_flags & IEEE80211_COMMON_OPT_NORMAL_QOS) && !DATA_FRAME_IS_QOS(frame_type_subtype)) {
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if (HAS_HT_CONTROL(FCF_FLAGS(fcf))) {
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/*
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* QoS data frames with the Order bit set have an HT Control field;
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* see 8.2.4.1.10 "Order field". If they're not HT frames, they
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* should never have the Order bit set.
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* Does it look as if we have a mesh header?
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* Look at the Mesh Control subfield of the QoS field and at the
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* purported mesh flag fields.
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*/
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hdr_len += 4;
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htc_len = 4;
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}
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/*
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* For locally originated mesh frames, the QoS header may be added by the
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* hardware, and no present in wireshark captures. This poses a problem
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* as the QoS header indicates the presence of the mesh control header.
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*
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* Instead of QoS, we use a few heuristics to determine the presence of
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* the mesh control header, which is tricky because it can have a
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* variable length.
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*
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* Assume minimal length, and then correct if wrong.
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*/
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meshctl_len = find_mesh_control_length(0);
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if (tvb_bytes_exist(tvb, hdr_len, meshctl_len)) {
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meshoff = hdr_len;
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mesh_flags = tvb_get_guint8(tvb, meshoff);
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/* now find correct length */
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meshctl_len = find_mesh_control_length(mesh_flags);
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/* ... and try to read two bytes of next header */
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if (tvb_bytes_exist(tvb, hdr_len, meshctl_len + 2)) {
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guint16 next_header = tvb_get_letohs(tvb, meshoff + meshctl_len);
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if (has_mesh_control_local(fcf, mesh_flags, next_header)) {
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qos_control = tvb_get_letohs(tvb, qosoff);
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if (tvb_bytes_exist(tvb, hdr_len, 1)) {
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meshoff = hdr_len;
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mesh_flags = tvb_get_guint8(tvb, meshoff);
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if (has_mesh_control(fcf, qos_control, mesh_flags)) {
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/* Yes, add the length of that in as well. */
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meshctl_len = find_mesh_control_length(mesh_flags);
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hdr_len += meshctl_len;
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break;
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}
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}
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} else {
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if (HAS_HT_CONTROL(FCF_FLAGS(fcf))) {
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/*
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* QoS data frames with the Order bit set have an HT Control field;
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* see 8.2.4.1.10 "Order field". If they're not HT frames, they
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* should never have the Order bit set.
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*/
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hdr_len += 4;
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htc_len = 4;
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}
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/*
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* For locally originated mesh frames, the QoS header may be added
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* by the hardware, and no present in wireshark captures. This
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* poses a problem as the QoS header indicates the presence of the
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* mesh control header.
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*
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* Instead of QoS, we use a few heuristics to determine the presence
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* of the mesh control header, which is tricky because it can have a
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* variable length.
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*
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* Assume minimal length, and then correct if wrong.
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*/
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meshctl_len = find_mesh_control_length(0);
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if (tvb_bytes_exist(tvb, hdr_len, meshctl_len)) {
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meshoff = hdr_len;
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mesh_flags = tvb_get_guint8(tvb, meshoff);
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/* now find correct length */
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meshctl_len = find_mesh_control_length(mesh_flags);
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/* ... and try to read two bytes of next header */
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if (tvb_bytes_exist(tvb, hdr_len, meshctl_len + 2)) {
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guint16 next_header = tvb_get_letohs(tvb, meshoff + meshctl_len);
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if (has_mesh_control_local(fcf, mesh_flags, next_header)) {
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/* Yes, add the length of that in as well. */
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hdr_len += meshctl_len;
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break;
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}
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}
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}
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/* failed to find a mesh header */
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meshctl_len = 0;
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}
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/* failed to find a mesh header */
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meshctl_len = 0;
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}
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break;
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