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2017-05-12trafgen: disable NLS in the parserTobias Klauser1-2/+0
There is no point in having the parser show translated error messages while the rest of the program does only show them in English. Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2017-02-09trafgen: parser: Rename bytes -> macVadim Kochan1-6/+6
Rename <bytes> token member to <mac> as it is used only for MAC address parsing, for dynamic sized bytes array we have <str>. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2017-02-09make: Fix spelling yaac -> yaccTobias Klauser1-1/+1
The parser generator's name is yacc, not yaac. Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2017-02-09trafgen: Allow send packets from pcap fileVadim Kochan1-1/+1
Add ability to send packets from pcap file if it has ".pcap" extension via "-i,--in" option. By default packet sending is delayed considering original packets timestamps if no rate or delay is specified via -b/-t options. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2017-01-11trafgen: parser: Add terminating ';' to mpls_expr and icmpv6_proto rulesTobias Klauser1-0/+3
The rules mpls_expr and icmpv6_proto are missing a terminating semicolon. Even though bison seems to accept the rules this way, make them consistent with all the others in the file. Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-12-21trafgen: parser: Allow to set function at field offsetVadim Kochan1-48/+120
Extend proto field expression to: proto_field[{index}:{len}] = {func} which allows to specify function on the field offset via index and value length (default is 1 - 1 byte). This rule is optional. It was needed to keep of proto_field's copies in packet_dyn->fields instead of original fields which allows to scpecify different functions on the different parts of same field, also the copy of original proto_field allows to set custom length/pkt_offset which makes such field behave as virtual sub-field of the original one with different length/pkt_offset but point to the same piece of header. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-12-21trafgen: parser: Parse IPv6 address by strict match patternVadim Kochan1-1/+1
Used IPv6 pattern from nftables project [1] to match valid only IPv6 address to do not mess with MAC or other syntax patterns with ':' symbol. [1] http://git.netfilter.org/nftables/tree/src/scanner.l Signed-off-by: Vadim Kochan <vadim4j@gmail.com> [tk: add refrence to nftables source] Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-12-21trafgen: proto: Rename proto_field_xxx -> proto_hdr_field_xxxVadim Kochan1-32/+32
Rename all proto_field_xxx(...) functions to proto_hdr_field(...). It is good for 2 reasons: 1) proto_hdr_field_xxx naming is more consistent as it is related to proto_hdr API. 2) It makes possible to introduce proto_field_xxx API which will operate only with struct proto_field. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-12-21trafgen: parser: Rename field_expr -> field_value_expr ruleVadim Kochan1-15/+15
Rename field_expr rule to field_value_expr to indicate the rule relates to field value part in case if there will be added field_expr rule to describe field expression syntax. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-12-16trafgen: proto: Zero out the correct packet slotTobias Klauser1-3/+3
In the third attempt, finally do the packet slot zeroing correctly. Zero the struct packet in __init_new_packet_slot() not the struct packet_dyn in __init_new_counter_slot(). Don't know what hit me yesterday... Fixes: d6d511ecff24 ("trafgen: proto: Zero out newly allocated struct packet") Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-12-15trafgen: proto: Add missing braceTobias Klauser1-1/+1
Fix the fat-fingered previous commit which I pushed out too early ;( Fixes: d6d511ecff24 ("trafgen: proto: Zero out newly allocated struct packet") Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-12-15trafgen: proto: Zero out newly allocated struct packetTobias Klauser1-2/+1
When allocating a new struct packet, the headers and headers_count fields are not zeroed and retain whatever value the allocator returned. Incidentally, this usually seems to have been zero. But on some systems (e.g. Ubuntu 16.04 with a self-compiled 4.9) it is not and we hit the following bug_on: trafgen: trafgen_proto.c:135: proto_header_push: Assertion `!(pkt->headers_count >= 16)' failed. Fix this by properly zeroing the entire struct packet. Fixes: e7dd63060e44 ("trafgen: proto: Update field value at runtime") Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-11-23trafgen: parser: Fix undefined ETH_P_802AD on 2.6.x LinuxVadim Kochan1-0/+4
ETH_P_8021AD might be undefined on 2.6.x Linux version (tested on Ubuntu 10 with 2.6.32 Linux), so lets check and define it. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-10-04trafgen: parser: Add 'pfc()' function for PFC headerVadim Kochan1-1/+39
Add 'pfc()' function for PFC header creation with fields: code - MAC Control opcode prio - Priority enable vector prio(0)..prio(7) - Enable/disable pause for prio X time(0)..time(7) - Set pause time for prio X Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-10-04trafgen: parser: Add 'pause()' function for IEEE 802.3X PAUSE headerVadim Kochan1-0/+27
Add 'pause()' proto header function for IEEE 802.3X PAUSE header generation with the fields: code - MAC Control opcode (default 0x0001) time - PAUSE time (default 0) Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-09-21trafgen: parser: Add 'drnd()' function for proto fieldsVadim Kochan1-0/+9
Add syntax for specify dynamic random function for proto field: drnd() | drnd(min, max) EXAMPLE: { udp(sport=drnd()) } { udp(sport=drnd(1000, 2000)) } Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-09-21trafgen: parser: Add support of 'dinc' function for proto fieldsVadim Kochan1-0/+53
Add 'dinc()' function in 'field_expr' rules to be used for dynamically incrementing of any specified field: SYNTAX := dinc() | dinc(step) | dinc(min, max) | dinc(min, max, step) EXAMPLES: { udp(sport=dinc() } { udp(sport=dinc(1) } { udp(sport=dinc(100, 125, 5) } Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-09-21trafgen: parser: Unify proto field value parsingVadim Kochan1-146/+215
Changed parsing logic of field value expression to be more generic. Such approach will allow to easy extend field value expression to support dynamic field functions. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-08-12trafgen: proto: Split static protocol definition out of struct proto_hdrTobias Klauser1-1/+1
Currently struct proto_hdr is used twofold: 1) Statically define protocol behavior, i.e. all the *_hdr definitions in trafgen_l{2,3,4}.c which map a protocol id/layer to a set of callback functions. 2) For each packet created at parse time the struct is memcpy()'ed (including all the static information from 1) and then used to store dynamic information at parse/run time. Thus, struct proto_hdr members such as the proto id, layer and the pointers callback functions get copied for each created packet (in addition to the other fields which get changed during parsing). Also, static/dynamic information get mixed and we e.g. can't make the protocol definitions const to ensure they'll not get changed by mistake. Rather than copying the struct proto_hdr for every packet, clearly separate the two purposes defined above by splitting struct proto_hdr into two structs: 1) struct proto_ops for the static (const) protocol behavior definition 2) struct proto_hdr (reduced) for dynamic information struct proto_hdr keeps a pointer to the corresponding proto_ops instance and uses it to execute the corresponding callbacks. Reference: https://groups.google.com/forum/#!msg/netsniff-ng/20RvwJdh50Y/eMkbmKSaBgAJ Acked-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-08-09trafgen: parser: Check read access to file before invoking cppTobias Klauser1-2/+8
If a non-accessible (or non-existing) file is passed to trafgen and the -p/--cpp option is used, the preprocessor will fail but trafgen will continue running and producing follow-up errors messages: cpp: error: foo.conf: No such file or directory cpp: warning: ā€˜-x cā€™ after last input file has no effect cpp: fatal error: no input files compilation terminated. 0 packets to schedule Enabled kernel qdisc bypass 0 bytes in total Running! Hang up with ^C! Enabled kernel qdisc bypass TX,V2: 0.50 MiB, 256 Frames, each 2048 Byte allocated TX,V2: 0.50 MiB, 256 Frames, each 2048 Byte allocated 0 packets outgoing 0 bytes outgoing 0 sec, 0 usec on CPU0 (0 packets) 0 sec, 0 usec on CPU1 (0 packets) To avoid this, check that the file is readable before passing it to the preprocessor and error out if is not readable. Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-08-02trafgen: proto: Move proto headers into packetVadim Kochan1-3/+13
Until now headers were used only for packet creation at compile time, which does not allow to handle dynamic field updates at runtime. To support dynamic updates, it is necessary to keep the proto_hdr entries around after packet compilation so we can reference the header fields to dynamically update. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> [tk: Adjust patch description, simplify code] Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-08-02trafgen: proto: Reference to packet from struct proto_hdrVadim Kochan1-0/+10
Using of current_packet() is not possible for dynamically updated fields so we need to keep the packet index in proto_hdr struct to reference the correct packet. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-07-13trafgen: proto: Add ICMPv4 header generationVadim Kochan1-1/+40
Support for generating ICMPv4 headers using the 'icmp4()/icmpv4()' trafgen generation functions. Fields supported: type Set type field (default 0: Echo reply) Supported keywords: echorequest, echoreply code Set code field (default 0) csum Set checksum field (calculated by default) mtu Set mtu field for destination unreachable (default 0) seq Set sequence field (default 0) id Set identifier field (default 0) addr Set redirect address (default 0.0.0.0) Example (send ping request): { icmpv4(echorequest, seq=1, id=1326) } Signed-off-by: Vadim Kochan <vadim4j@gmail.com> [tk: squash commits, consistency between functionality and docu] Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-07-11trafgen: parser: Replace 'mtype' by 'type'Vadim Kochan1-4/+4
After splitting etype & type to different tokens it is possible to use 'type' for ICMP type field which is used by RFC. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-07-11trafgen: parser: Split [e]type to separate keywordsVadim Kochan1-1/+2
Split [e]type to separate 'type' & 'etype' keywords, the reason is that 'type' might be used in other protocol headers (e.g. ICMP). Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-04-25trafgen: proto: Add ICMPv6 header generationTobias Klauser1-0/+34
Support for generating simple ICMPv6 headers using the 'icmp6()/icmpv6()' trafgen generation function. Fields supported: mtype Message type (default: 0) Supported keywords: echorequest, echoreply code Code (default: 0) csum Message checksum (calculated by default) Examples: { eth(), ipv6(daddr=::1), icmpv6(echorequest), 42, 42, 0, 0 }' If not explicitely specified, the lower header is initialized as Ethernet. Suggested-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-04-25trafgen: proto: Add IPv6 header generationTobias Klauser1-2/+44
Support for generating simple IPv6 headers using the 'ip6()/ipv6()' trafgen generation function. Fields supported: ver|version Version (default: 6) tc|tclass Traffic class (default: 0) fl|flow Flow Label (default: 0) len|length Payload length (calculated by default) nh|nexthdr Type of next header (default: 0) hl|hoplimit|ttl Hop Limit, TTL (default: 0) sa|saddr Source IPv6 address (default: device address) da|daddr Destination IPv6 address (default: 0:0:0:0:0:0:0:0) Examples: { eth(), ipv6(daddr=1:2:3:4:5:6:7:8) } { ipv6(tc=2, hl=3, daddr=::1) } { eth(), ipv6(nh=58, sa=2001:db8::, da=::1), 128, 0, 0x52, 0x03, 0, 0, 0, 0 } If not explicitely specified, the lower header is initialized as Ethernet. Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-02-23trafgen: parser: Add syntax for MPLS header creatingVadim Kochan1-1/+33
Add 'mpls()' function for creating MPLS header with parameters: lbl|label MPLS label last Indicates the last label on MPLS stack tc|tclass|exp Traffic Class (TC) ttl TTL (Time To Live) Currently only unicast MPLS is supported, but multicast might be set via 'eth()' function. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-02-02trafgen: parser: Add syntax for VLAN header creatingVadim Kochan1-0/+40
Add 'vlan()' function to generate VLAN header. Fields supported: tpid|proto Set TPID (Tag Protocol Identifier) (default 0x8100) 1ad Set TPID field as 0x88a8 1q Set TPID field as 0x8100 tci Set TCI (Tag Control Information) (default 0) pcp Set PCP (Priority Code Point) (PCP) (default 0) dei|cfi Set DEI (Drop Eligible Indicator) (default 0) id Set VID (VLAN Identifier) (default 0) Examples: { eth(), vlan(id=1), ipv4() } { vlan(id=1, 1ad), vlan(id=100, pcp=3), ipv4() } Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-02-02trafgen: proto: Simplify getting lower protocol after initVadim Kochan1-2/+1
Change proto_header_init(...) and proto_lower_default_add(...) functions to return struct proto_hdr * to do not call proto_current_header(...) after, so it makes more sense to get struct proto_hdr * right after initializing protocol by id. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-02-02trivial: trafgen: parser: Fix spacingTobias Klauser1-11/+11
Get rid of some unnecessary double spaces to make parsers rules look consistent. Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-02-01trafgen: parser: Fix parsing of "prot[o]" field in eth()Tobias Klauser1-1/+6
Commit 2ba202b introduced the [e]type field for specifiying the Ethertype, but at the same time made the existing "prot[o]" field name not work anymore. Fix it by providing a specific parser rule as it cannot be solved in the lexer grammar alone (which will always use the first matching token). Fixes: 2ba202b ("trafgen: parser: Support "etype"/"type" keywords for Ethertype") Reported-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-02-01trafgen: parser: Add TCP header generation functionTobias Klauser1-1/+44
Add a function 'tcp()' to generate TCP headers from the trafgen configuration language. Fields supported: sp|sport TCP source port (default 0) dp|dport TCP destination port (default 0) seq Sequence number (default: 0) aseq|ackseq Acknowledgement number (default 0) doff|hlen Header length/data offset (default: 5) cwr Congestion Window Reduced flag (default: 0) ece|ecn ECN-Echo flag (default: 0) urg Urgent flag (default: 0) ack Acknowledgement flag (default: 0) psh Push flag (default: 0) rst Reset flag (default: 0) syn Synchronize flag (default: 0) fin Finish flag (default: 0) win|window Receive window size (default: 0) csum Checksum field (calculated automatically) urgptr Urgent pointer (default: 0) Example (SYN on port 80/http): { tcp(dport=80, syn, window=5840) } Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-01-29trafgen: parser: Rename IPv4 specific types and union membersTobias Klauser1-7/+7
Rename lexer/parser type and union member ip_addr to ip4_addr. This will make it easier to distinguish from IPv6 addresses, to be added an a follow-up patch. Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-01-29trafgen: parser: Support "etype"/"type" keywords for EthertypeTobias Klauser1-4/+4
The IEEE 802.3 standard commonly refers to the field specifying the upper layer protocol as Ethertype, not protocol. Thus, also support the keywords "etype" and "type" for this field. Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-01-29trafgen: parser: Add syntax to build UDP headerVadim Kochan1-0/+29
Add function 'udp()' to generate UDP header. Fields supported: sp|sport UDP source port (default 0) dp|dport UDP destination port (default 0) len|length Length of UDP header + payload (calculated automatically) csum Checksum field (calculated automatically) Example (Echo request): { udp(dport=7) } Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-01-29trafgen: parser: Add syntax for IPv4 protocol generationVadim Kochan1-0/+51
Add 'ip4(), ipv4()' function to build IPv4 header. Fields supported: ihl IPv4 header length (default 5 ) ver|version IPv4 version (default 4) ttl Time To Live (TTL) field (default 0) dscp DiffServ field (default 0) ecn ECN bits (default 0) tos TOS (DSCP + ECN) field (default 0) len|length IPv4 header + payload length (calculated by default) id Identifier (default 0) flags Flags field (default 0) frag Fragment offset (default 0) csum IPv4 header checksum (calculated by default) df Set DF (Dont Fragment) bit to 1 (default is 0) mf Set MF (More Fragments) bit to 1 (default is 0) sa|saddr IPv4 source address (default used from output device) da|daddr IPv4 destination address (default 0.0.0.0) proto IPv4 protocol id (default 0) Example: { ip4(df, mf, frag=100, prot=0x1, ecn=2, dscp=20) } { ip4(da=1.1.1.1), ip4(sa=3.3.3.3, da=3.3.3.4) } Last example generates IP-in-IP packet. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-01-28trafgen: parser: Add syntax to generate ARP header fieldsVadim Kochan1-1/+47
Add function 'arp()' to support generating ARP header fields from the trafgen configuration language. Supported fields: htype hardware type, default: 1 (Ethernet) ptype protocol type, default: 0x0800 (IP) op|oper operation (req|request, reply, <num>), default: 1 (request) sha|smac sender MAC address, default: device MAC spa|sip sender IP address, default: device IP tha|tmac target MAC address, default: 00:00:00:00:00:00 tpa|tip target IP address, default: 0.0.0.0 Note: setting hlen and tlen is not supported, these will by set to hlen=6 and plen=4 in any case. Example usage: { arp(op=request, sip=1.1.1.1, smac=11:22:33:44:55:66, tip=42.42.42.42) } { arp() } Signed-off-by: Vadim Kochan <vadim4j@gmail.com> [tk: document keywords in commit message] Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-01-28trafgen: parser: Add syntax to generate Ethernet header fieldsVadim Kochan1-1/+56
Add function 'eth()' to support generating Ethernet header fields from the trafgen configuration language. Supported fields: da|daddr destination address, default: 00:00:00:00:00:00 sa|saddr source address, default: device MAC prot|proto protocol number, default: 0x0000 Example usage: { eth(prot=0x0800, da=11:22:33:44:55:66), fill(0xff, 60) } { eth(prot=0x0800) } { eth() } It is important that proto_init is called before fields will be filled to initialize the specified proto with header fields. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> [tk: document supported keywords in commit message] Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-01-28trafgen: Add helper to get current packetVadim Kochan1-0/+5
Add current_packet() helper for getting current used packet and make it public to other modules. It will be used by proto generation logic. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2016-01-28trafgen: Export set_fill funcVadim Kochan1-1/+1
Make public set_fill func to be used by proto generation code. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2015-12-17cpp: Constify cpp argv passed to cpp_execTobias Klauser1-2/+2
Pass argv as char *const argv[] as execvp expects it. Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2015-12-17trafgen: Added option to pass macro/define for C preprocessorVadim Kochan1-2/+3
Add -D,--define option which allows to pass multiple macro/defines which can be used in trafgen script (e.g. by #ifdef ). Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2015-12-17cpp: Allow to pass additional cpp optionsVadim Kochan1-1/+1
Extend cpp_exec function with args parameter to specify additional cpp options (like -D). Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2015-11-25trafgen: Make sure yyin is set before close itVadim Kochan1-1/+1
In case if cpp failed then it is possible that trafgen may hang on closing uninitialized yyin. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2015-11-24trafgen: Invoke C preprocessor from cpp.c moduleVadim Kochan1-12/+2
Use cpp_exec func to invoke C preprocesor. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2015-11-10bpfc, trafgen: Do not close stdin when "-" is specifiedVadim Kochan1-1/+2
Do not perform fclose for stdin fd. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2015-11-09csum: Remove unused parameter from calc_csum()Tobias Klauser1-1/+1
The `ccsum' parameter to calc_csum() is never used and is set to 0 by all callers. There's no reason to keep it, so remove it. Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2015-11-09trafgen: Allow to build packet from command lineVadim Kochan1-0/+25
Craft packet directly from command line with same syntax as for conf file. It might be as first step to extend current syntax with specific proto fields. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
2015-10-14trafgen: Move checking of dynamic packet elements to headerTobias Klauser1-6/+1
Move has_dynamic_elems() to to trafgen_conf.h, rename it to packet_dyn_has_elems() and use it to check whether dynamic packet elements are present. Also change the return type to bool and use || instead of + to potentially make use of short-circuit evaluation. Signed-off-by: Tobias Klauser <tklauser@distanz.ch>