P4のはなし

Transcript

1. 1ͷ͸ͳ͠
   ઙؒਖ਼࿨ˏ༗ݶձࣾۜ࠲ಊ
   &/0(
   
   ωοτϫʔΫΤϯδχΞͳΒ
   ڭཆͱ͓͓͖͍ͯ͑ͯͨ͠͞
   

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2. 1ͬͯʁ
   w 1SPHSBNNJOH1SPUPDPMJOEFQFOEFOU1BDLFU1SPDFTTPSTͷུ
   w ύέοτΛड͚औ͔ͬͯΒͦͷத਎ʹԠͯ͡ॲཧΛߦ͍ૹΓग़͢·Ͱ
   ͷಈ࡞Λهड़͢ΔͨΊͷϓϩάϥϛϯάݴޠ
   ‛ σʔλϓϨʔϯΛهड़͢ΔͨΊͷݴޠ
   w 1Ͱ͸ಛఆͷϓϩτίϧʹґଘ͠ͳ͍ 1SPUPDPMJOEFQFOEFOU
   
   ύέοτॲཧܥʹର͢Δύέοτͷॲཧ಺༰Λ࣮૷͢Δ͜ͱ͕Ͱ͖Δ
   ‛ ৽͍͠ϓϩτίϧ͕ఆٛ͞ΕͨΒͦͷϓϩτίϧʹରԠ͢Δॲ
   ཧΛ1Ͱϓϩάϥϛϯά͢Δ͜ͱͰରԠ͢Δ͜ͱ͕Ͱ͖Δ
   w ݴޠ࢓༷Ͱ͸ωοτϫʔΫػثͷΞʔΩςΫνϟΛنఆ͠ͳ͍
   ‛ ୠ͠ඪ४తͳΞʔΩςΫνϟ͸ࡦఆத 14"
   
   w ݴޠ࢓༷ʹ͸ίϯτϩʔϧϓϨʔϯ͔ΒσʔλϓϨʔϯΛૢ࡞͢Δ"1*
   ͸ؚ·Εͳ͍
   ‛ ୠ͠1ίϛϡχςΟͰ͸ίϯτϩʔϧϓϨʔϯ͔ΒσʔλϓϨʔ
   ϯΛૢ࡞͢ΔͨΊͷ"1*΋ࡦఆத 1*
   
   2
   

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3. എܠ
   
   w 0QFO'MPXͰ͸৽͍͠ϓϩτίϧʹରԠͰ͖ͳ͍
   w ૿͑ଓ͚ΔϔομϑΟʔϧυ
   w େ͖͘ͳΓଓ͚Δ࢓༷
   3
   1BU#PTTIBSU %BO%BMZ (MFO(JCC .BSUJO*[[BSE /JDL.D,FPXO +FOOJGFS
   3FYGPSE $PMF4DIMFTJOHFS %BO5BMBZDP "NJO7BIEBU (FPSHF7BSHIFTF
   %BWJE8BMLFS l1SPHSBNNJOH1SPUPDPMJOEFQFOEFOU1BDLFU1SPDFTTPST z
   IUUQTBSYJWPSHQEGQEG͔ΒҾ༻
   Software-Defined Networking (SDN) gives operators pro-
   grammatic control over their networks. In SDN, the con-
   trol plane is physically separate from the forwarding plane,
   and one control plane controls multiple forwarding devices.
   While forwarding devices could be programmed in many
   ways, having a common, open, vendor-agnostic interface
   (like OpenFlow) enables a control plane to control forward-
   ing devices from di↵erent hardware and software vendors.
   Version Date Header Fields
   OF 1.0 Dec 2009 12 fields (Ethernet, TCP/IPv4)
   OF 1.1 Feb 2011 15 fields (MPLS, inter-table metadata)
   OF 1.2 Dec 2011 36 fields (ARP, ICMP, IPv6, etc.)
   OF 1.3 Jun 2012 40 fields
   OF 1.4 Oct 2013 41 fields
   Table 1: Fields recognized by the OpenFlow standard
   The OpenFlow interface started simple, with the abstrac-
   tion of a single table of rules that could match packets on a
   dozen header fields (e.g., MAC addresses, IP addresses, pro-
   tocol, TCP/UDP port numbers, etc.). Over the past five
   years, the specification has grown increasingly more com-
   Figur
   Recen
   be achie
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   arXiv:1312
   

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4. എܠ
   
   4
   ιϑτ΢ΣΞϧʔλ 1ΞʔΩςΫνϟ ϋʔυ΢ΣΞεΠον
   ॲཧ
   ൚༻ϓϩηοα
   $16
   
   ϓϩάϥϚϒϧ"4*$
   '1("$16౳
   ઐ༻ϓϩηοα
   "4*$
   '1("
   ੑೳ
   ϋʔυ΢ΣΞεΠον
   ͱൺֱ͢Δͱ௿଎
   ߴ଎͔ͭେ༰ྔ
   $16ͷ৔߹͸আ͘
   
   ߴ଎͔ͭେ༰ྔ
   ϙʔτີ౓ ௿͍
   ߴ͍
   $16ͷ৔߹͸আ͘
   
   ߴ͍
   ஗Ԇ2P4 อূͰ͖ͳ͍
   อূ͠΍͍͢
   $16ͷ৔߹͸আ͘
   
   อূ͠΍͍͢
   ৽͍͠ϓϩτίϧ
   ରԠ
   ιϑτ΢ΣΞͷॻ͖׵
   ͑ͰରԠՄೳ
   1ϓϩάϥϜͷॻ͖׵
   ͑ͰରԠՄೳ
   "4*$Ͱ͸΄΅ෆՄೳ
   ϑϧ'1("ͷ৔߹Մೳ
   Ձ֨ ൺֱత͍҆
   ͨͿΜߴ͍͆
   $16ͷ৔߹͸আ͘
   
   ൺֱతߴ͍
   

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5. 5
   ར༻ऀ ϓϩάϥϚ
   
   Πϥετ $
   ͍Β͢ͱ΍
   λʔήοτ ΞʔΩςΫνϟ
   
   ػثϝʔΧʔ
   1ίϛϡχςΟ
   DPSFQ
   QSPHSBNQ
   BSDIQ
   Πϯετʔϧ
   ίϯύΠϧ
   ొ৔ਓ෺
   1ϓϩάϥϜ
   

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6. 6
   λʔήοτ ΞʔΩςΫνϟ
   
   ػثϝʔΧʔ
   QSPHSBNQ
   BSDIQ
   Πϯετʔϧ
   ίϯύΠϧ
   1ϓϩάϥϜ
   ొ৔ਓ෺
   DPSFQ
   ར༻ऀ ϓϩάϥϚ
   
   1ίϛϡχςΟ
   w ίΞϥΠϒϥϦ
   w ΤϥʔίʔυɺύέοτΛ
   ද͢ߏ଄ମɺͳͲͷΞʔΩ
   ςΫνϟͱ1ϓϩάϥϜ
   ͕ڞ௨Ͱ༻͍Δ΋ͷΛఆٛ
   Πϥετ $
   ͍Β͢ͱ΍
   

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7. 7
   QSPHSBNQ Πϯετʔϧ
   ίϯύΠϧ
   DPSFQ
   1ίϛϡχςΟ
   1ϓϩάϥϜ
   ػثϝʔΧʔ
   BSDIQ
   ར༻ऀ ϓϩάϥϚ
   
   ొ৔ਓ෺
   Πϥετ $
   ͍Β͢ͱ΍
   λʔήοτ ΞʔΩςΫνϟ
   
   w ΞʔΩςΫνϟએݴ
   w λʔήοτ༻ʹ1ϓϩά
   ϥϜΛॻ͘ࡍʹ࣮૷͠ͳ͚
   Ε͹ͳΒͳ͍΋ͷ ύʔα
   ΍ίϯτϩʔϧ౳
   ͷએݴ
   

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8. 8
   λʔήοτ ΞʔΩςΫνϟ
   
   ػثϝʔΧʔ
   BSDIQ
   Πϯετʔϧ
   ίϯύΠϧ
   DPSFQ
   1ίϛϡχςΟ
   QSPHSBNQ
   ొ৔ਓ෺
   ར༻ऀ ϓϩάϥϚ
   
   Πϥετ $
   ͍Β͢ͱ΍
   w 1ϓϩάϥϜ
   w ΞʔΩςΫνϟએݴͰએݴ
   ͞Εͨύʔαɺίϯτϩʔ
   ϧɺσύʔαΛ࣮૷
   w ͦΕΒΛ·ͱΊͯΞʔΩς
   ΫνϟએݴͰએݴ͞Εͨύο
   έʔδͷΠϯελϯεͱ͠
   ͯΠϯελϯεԽ
   1ϓϩάϥϜ
   

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9. 9
   ར༻ऀ ϓϩάϥϚ
   
   λʔήοτ ΞʔΩςΫνϟ
   
   ػثϝʔΧʔ
   1ίϛϡχςΟ
   DPSFQ
   QSPHSBNQ
   BSDIQ
   Πϯετʔϧ
   ίϯύΠϧ
   ొ৔ਓ෺
   Πϥετ $
   ͍Β͢ͱ΍
   1ϓϩάϥϜ
   

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10. ΞʔΩςΫνϟ৭ʑ
    w 7.PEFM
    w 1ίϛϡχςΟʹΑͬͯϝϯςφϯε͞Ε͍ͯΔϏϔΠϏΞϞσϧ
    ιϑτ΢ΣΞ࣮૷εΠον
    ͕αϙʔτ͢ΔΞʔΩςΫνϟ
    w 1ϓϩάϥϜͷ࣮ݧΛ͢ΔҝͷΞʔΩςΫνϟʁ
    w 1PSUBCMF4XJUDI"SDIJUFDUVSF 14"
    
    w 1ίϛϡχςΟʹΑͬͯඪ४Խ͕ਐΊΒΕ͍ͯΔඪ४తͳωοτ
    ϫʔΫεΠονΛදݱ͢ΔΞʔΩςΫνϟ
    w 14"Λλʔήοτʹ͓͚ͯ͠͹14"ରԠͷػث͕ग़ͨ࣌ʹ༰қʹϙʔ
    ςΟϯάͰ͖Δʁ
    w 1ϓϩάϥϜͰ͸্هͷਫ৭ͷ࢛֯ͷ෦෼Λ࣮૷͢Δ
    10
    *OHSFTT
    1BSTFS
    &HSFTT
    %FQBSTFS
    *OHSFTT
    *OHSFTT
    %FQBSTFS
    1LU#VG
    3FQMJDB
    &HSFTT
    1BSTFS
    &HSFTT
    #VG2VFVF
    &OHJOF
    5SB⒏D
    .BOBHFS
    1BSTFS %FQBSTFS
    7FSJGZ
    $IFDLTVN
    *OHSFTT &HSFTT
    $PNQVUF
    $IFDLTVN
    

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11. ΞʔΩςΫνϟ৭ʑ
    w 7.PEFM
    w 1ίϛϡχςΟʹΑͬͯϝϯςφϯε͞Ε͍ͯΔϏϔΠϏΞϞσϧ
    ιϑτ΢ΣΞ࣮૷εΠον
    ͕αϙʔτ͢ΔΞʔΩςΫνϟ
    w 1ϓϩάϥϜͷ࣮ݧΛ͢ΔҝͷΞʔΩςΫνϟʁ
    w 1PSUBCMF4XJUDI"SDIJUFDUVSF 14"
    
    w 1ίϛϡχςΟʹΑͬͯඪ४Խ͕ਐΊΒΕ͍ͯΔඪ४తͳωοτ
    ϫʔΫεΠονΛදݱ͢ΔΞʔΩςΫνϟ
    w 14"Λλʔήοτʹ͓͚ͯ͠͹14"ରԠͷػث͕ग़ͨ࣌ʹ༰қʹϙʔ
    ςΟϯάͰ͖Δʁ
    w 1ϓϩάϥϜͰ͸্هͷਫ৭ͷ࢛֯ͷ෦෼Λ࣮૷͢Δ
    11
    *OHSFTT
    1BSTFS
    &HSFTT
    %FQBSTFS
    *OHSFTT
    *OHSFTT
    %FQBSTFS
    1LU#VG
    3FQMJDB
    &HSFTT
    1BSTFS
    &HSFTT
    #VG2VFVF
    &OHJOF
    5SB⒏D
    .BOBHFS
    1BSTFS %FQBSTFS
    7FSJGZ
    $IFDLTVN
    *OHSFTT &HSFTT
    $PNQVUF
    $IFDLTVN
    w ύʔα
    w ύέοτͷϔομΛղੳ͢Δ෦෼
    

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12. ΞʔΩςΫνϟ৭ʑ
    w 7.PEFM
    w 1ίϛϡχςΟʹΑͬͯϝϯςφϯε͞Ε͍ͯΔϏϔΠϏΞϞσϧ
    ιϑτ΢ΣΞ࣮૷εΠον
    ͕αϙʔτ͢ΔΞʔΩςΫνϟ
    w 1ϓϩάϥϜͷ࣮ݧΛ͢ΔҝͷΞʔΩςΫνϟʁ
    w 1PSUBCMF4XJUDI"SDIJUFDUVSF 14"
    
    w 1ίϛϡχςΟʹΑͬͯඪ४Խ͕ਐΊΒΕ͍ͯΔඪ४తͳωοτ
    ϫʔΫεΠονΛදݱ͢ΔΞʔΩςΫνϟ
    w 14"Λλʔήοτʹ͓͚ͯ͠͹14"ରԠͷػث͕ग़ͨ࣌ʹ༰қʹϙʔ
    ςΟϯάͰ͖Δʁ
    w 1ϓϩάϥϜͰ͸্هͷਫ৭ͷ࢛֯ͷ෦෼Λ࣮૷͢Δ
    12
    *OHSFTT
    1BSTFS
    &HSFTT
    %FQBSTFS
    *OHSFTT
    *OHSFTT
    %FQBSTFS
    1LU#VG
    3FQMJDB
    &HSFTT
    1BSTFS
    &HSFTT
    #VG2VFVF
    &OHJOF
    5SB⒏D
    .BOBHFS
    1BSTFS %FQBSTFS
    7FSJGZ
    $IFDLTVN
    *OHSFTT &HSFTT
    $PNQVUF
    $IFDLTVN
    w ϚονΞΫγϣϯύΠϓϥΠϯ
    w ϔομͷ஋ʹԠͯ͡Կ͔ॲཧ ΞΫγϣϯ
    Λߦ͏෦෼
    

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13. ΞʔΩςΫνϟ৭ʑ
    w 7.PEFM
    w 1ίϛϡχςΟʹΑͬͯϝϯςφϯε͞Ε͍ͯΔϏϔΠϏΞϞσϧ
    ιϑτ΢ΣΞ࣮૷εΠον
    ͕αϙʔτ͢ΔΞʔΩςΫνϟ
    w 1ϓϩάϥϜͷ࣮ݧΛ͢ΔҝͷΞʔΩςΫνϟʁ
    w 1PSUBCMF4XJUDI"SDIJUFDUVSF 14"
    
    w 1ίϛϡχςΟʹΑͬͯඪ४Խ͕ਐΊΒΕ͍ͯΔඪ४తͳωοτ
    ϫʔΫεΠονΛදݱ͢ΔΞʔΩςΫνϟ
    w 14"Λλʔήοτʹ͓͚ͯ͠͹14"ରԠͷػث͕ग़ͨ࣌ʹ༰қʹϙʔ
    ςΟϯάͰ͖Δʁ
    w 1ϓϩάϥϜͰ͸্هͷਫ৭ͷ࢛֯ͷ෦෼Λ࣮૷͢Δ
    13
    *OHSFTT
    1BSTFS
    &HSFTT
    %FQBSTFS
    *OHSFTT
    *OHSFTT
    %FQBSTFS
    1LU#VG
    3FQMJDB
    &HSFTT
    1BSTFS
    &HSFTT
    #VG2VFVF
    &OHJOF
    5SB⒏D
    .BOBHFS
    1BSTFS %FQBSTFS
    7FSJGZ
    $IFDLTVN
    *OHSFTT &HSFTT
    $PNQVUF
    $IFDLTVN
    w σύʔα
    w ϔομΛॻ͖׵͑Δ෦෼
    

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14. ίΞϥΠϒϥϦ
    14
    IUUQTHJUIVCDPNQMBOHQDCMPCNBTUFSQJODMVEFDPSFQ
    22 /// Standard error codes. New error codes can be declared by users.
    23 error {
    24 NoError, /// No error.
    25 PacketTooShort, /// Not enough bits in packet for 'extract'.
    26 NoMatch, /// 'select' expression has no matches.
    27 StackOutOfBounds, /// Reference to invalid element of a header stack.
    28 HeaderTooShort, /// Extracting too many bits into a varbit field.
    29 ParserTimeout /// Parser execution time limit exceeded.
    30 }
    66 /// Built-in action that does nothing.
    67 action NoAction() {}
    69 /// Standard match kinds for table key fields.
    70 /// Some architectures may not support all these match kinds.
    71 /// Architectures can declare additional match kinds.
    72 match_kind {
    73 /// Match bits exactly.
    74 exact,
    75 /// Ternary match, using a mask.
    76 ternary,
    77 /// Longest-prefix match.
    78 lpm
    79 }
    

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15. ίΞϥΠϒϥϦ
    15
    IUUQTHJUIVCDPNQMBOHQDCMPCNBTUFSQJODMVEFDPSFQ
    32 extern packet_in {
    33 /// Read a header from the packet into a fixed-sized header @hdr and advance the cursor.
    34 /// May trigger error PacketTooShort or StackOutOfBounds.
    35 /// @T must be a fixed-size header type
    36 void extract(out T hdr);
    37 /// Read bits from the packet into a variable-sized header @variableSizeHeader
    38 /// and advance the cursor.
    39 /// @T must be a header containing exactly 1 varbit field.
    40 /// May trigger errors PacketTooShort, StackOutOfBounds, or HeaderTooShort.
    41 void extract(out T variableSizeHeader,
    42 in bit<32> variableFieldSizeInBits);
    43 /// Read bits from the packet without advancing the cursor.
    44 /// @returns: the bits read from the packet.
    45 /// T may be an arbitrary fixed-size type.
    46 T lookahead();
    47 /// Advance the packet cursor by the specified number of bits.
    48 void advance(in bit<32> sizeInBits);
    49 /// @return packet length in bytes. This method may be unavailable on
    50 /// some target architectures.
    51 bit<32> length();
    52 }
    

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16. ίΞϥΠϒϥϦ
    16
    IUUQTHJUIVCDPNQMBOHQDCMPCNBTUFSQJODMVEFDPSFQ
    54 extern packet_out {
    55 /// Write @hdr into the output packet, advancing cursor.
    56 /// @T can be a header type, a header stack, a header_union, or a struct
    57 /// containing fields with such types.
    58 void emit(in T hdr);
    59 }
    61 // TODO: remove from this file, convert to built-in
    62 /// Check a predicate @check in the parser; if the predicate is true do nothing,
    63 /// otherwise set the parser error to @toSignal, and transition to the `reject` state.
    64 extern void verify(in bool check, in error toSignal);
    

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17. ΞʔΩςΫνϟએݴ 7.PEFMͷྫ
    
    17
    IUUQTHJUIVCDPNQMBOHQDCMPCNBTUFSQJODMVEFWNPEFMQ
    218 parser Parser(packet_in b,
    219 out H parsedHdr,
    220 inout M meta,
    221 inout standard_metadata_t standard_metadata);
    ... লུ ...
    229 @pipeline
    230 control Ingress(inout H hdr,
    231 inout M meta,
    232 inout standard_metadata_t standard_metadata);
    233 @pipeline
    234 control Egress(inout H hdr,
    235 inout M meta,
    236 inout standard_metadata_t standard_metadata);
    ... লུ ...
    244 @deparser
    245 control Deparser(packet_out b, in H hdr);
    247 package V1Switch(Parser p,
    248 VerifyChecksum vr,
    249 Ingress ig,
    250 Egress eg,
    251 ComputeChecksum ck,
    252 Deparser dep
    253 );
    5SB⒏D
    .BOBHFS
    1BSTFS %FQBSTFS
    7FSJGZ
    $IFDLTVN
    *OHSFTT &HSFTT
    $PNQVUF
    $IFDLTVN
    

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18. 1ϓϩάϥϜͷྫ
    18
    IUUQTHJUIVCDPNQMBOHUVUPSJBMTCMPCNBTUFS1%@@'BMMFYFSDJTFTCBTJDTPMVUJPOCBTJDQ
    2 #include
    3 #include
    11 typedef bit<9> egressSpec_t;
    12 typedef bit<48> macAddr_t;
    13 typedef bit<32> ip4Addr_t;
    15 header ethernet_t {
    16 macAddr_t dstAddr;
    17 macAddr_t srcAddr;
    18 bit<16> etherType;
    19 }
    21 header ipv4_t {
    22 bit<4> version;
    23 bit<4> ihl;
    ... লུ ...
    29 bit<8> ttl;
    30 bit<8> protocol;
    31 bit<16> hdrChecksum;
    32 ip4Addr_t srcAddr;
    33 ip4Addr_t dstAddr;
    34 }
    40 struct headers {
    41 ethernet_t ethernet;
    42 ipv4_t ipv4;
    43 }
    

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19. 1ϓϩάϥϜͷྫ
    19
    IUUQTHJUIVCDPNQMBOHUVUPSJBMTCMPCNBTUFS1%@@'BMMFYFSDJTFTCBTJDTPMVUJPOCBTJDQ
    49 parser MyParser(packet_in packet,
    50 out headers hdr,
    51 inout metadata meta,
    52 inout standard_metadata_t standard_metadata) {
    53
    54 state start {
    55 transition parse_ethernet;
    56 }
    57
    58 state parse_ethernet {
    59 packet.extract(hdr.ethernet);
    60 transition select(hdr.ethernet.etherType) {
    61 TYPE_IPV4: parse_ipv4;
    62 default: accept;
    63 }
    64 }
    65
    66 state parse_ipv4 {
    67 packet.extract(hdr.ipv4);
    68 transition accept;
    69 }
    70
    71 }
    ࢀߟ) v1model.p4
    218 parser Parser(packet_in b,
    219 out H parsedHdr,
    220 inout M meta,
    221 inout standard_metadata_t standard_metadata);
    

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20. 1ϓϩάϥϜͷྫ
    20
    IUUQTHJUIVCDPNQMBOHUVUPSJBMTCMPCNBTUFS1%@@'BMMFYFSDJTFTCBTJDTPMVUJPOCBTJDQ
    86 control MyIngress(inout headers hdr,
    87 inout metadata meta,
    88 inout standard_metadata_t standard_metadata) {
    ... লུ ...
    93 action ipv4_forward(macAddr_t dstAddr, egressSpec_t port) {
    94 standard_metadata.egress_spec = port;
    95 hdr.ethernet.srcAddr = hdr.ethernet.dstAddr;
    96 hdr.ethernet.dstAddr = dstAddr;
    97 hdr.ipv4.ttl = hdr.ipv4.ttl - 1;
    98 }
    100 table ipv4_lpm {
    101 key = {
    102 hdr.ipv4.dstAddr: lpm;
    103 }
    104 actions = {
    105 ipv4_forward;
    106 drop;
    107 NoAction;
    108 }
    109 size = 1024;
    110 default_action = NoAction();
    111 }
    113 apply {
    114 if (hdr.ipv4.isValid()) {
    115 ipv4_lpm.apply();
    116 }
    117 }
    118 }
    ࢀߟ) v1model.p4
    229 @pipeline
    230 control Ingress(inout H hdr,
    231 inout M meta,
    232 inout standard_metadata_t standard_metadata);
    

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21. 1ϓϩάϥϜͷྫ
    21
    IUUQTHJUIVCDPNQMBOHUVUPSJBMTCMPCNBTUFS1%@@'BMMFYFSDJTFTCBTJDTPMVUJPOCBTJDQ
    158 control MyDeparser(packet_out packet, in headers hdr) {
    159 apply {
    160 packet.emit(hdr.ethernet);
    161 packet.emit(hdr.ipv4);
    162 }
    163 }
    ࢀߟ) v1model.p4
    247 package V1Switch(Parser p,
    248 VerifyChecksum vr,
    249 Ingress ig,
    250 Egress eg,
    251 ComputeChecksum ck,
    252 Deparser dep
    253 );
    ࢀߟ) v1model.p4
    244 @deparser
    245 control Deparser(packet_out b, in H hdr);
    169 V1Switch(
    170 MyParser(),
    171 MyVerifyChecksum(),
    172 MyIngress(),
    173 MyEgress(),
    174 MyComputeChecksum(),
    175 MyDeparser()
    176 ) main;
    

    View Slide

22. ύʔα
    w ύέοτͷϔομΛղੳ͢Δ෦෼
    w ύʔε͢Δύέοτ͸QBDLFU@JOͱͯ͠౉͞ΕΔ
    w QBDLFU@JOͷFYUSBDUϝιου΍MPPLBIFBEϝιου΍BEWBODFϝιο
    υΛ༻͍ͯϔομΛղੳ͠ϔομߏ଄ମʹͦͷ৘ใΛ֨ೲ͍ͯ͘͠
    w QBDLFU@JOͷFYUSBDUϝιουΛ࣮

    ߦ͢ΔͱҾ਺ͷϑΟʔϧυ෼ύέ

    οτ͕ॖΈҾ਺ʹ஋͕֨ೲ͞ΕΔ

    ৄࡉޙड़
    
    w ঢ়ଶػցΛ࣋ͪॳظঢ়ଶTUBSU͔Β

    ࠷ऴతʹ͸BDDFQU͔SFKFDUʹࢸΔ
    w USBOTJUJPOͰ࣍ͷঢ়ଶʹҠߦ͢Δ
    w TFMFDUΛ࣮ߦ͢ΔͱҾ਺ͷ஋ʹԠ

    ͨ͡ঢ়ଶΛฦ͢͜ͱ͕Ͱ͖Δ
    w ঢ়ଶ͸࠶ؼՄೳ
    22
    49 parser MyParser(packet_in packet,
    50 out headers hdr,
    51 inout metadata meta,
    52 inout standard_metadata_t sta
    53
    54 state start {
    55 transition parse_ethernet;
    56 }
    57
    58 state parse_ethernet {
    59 packet.extract(hdr.ethernet);
    60 transition select(hdr.ethernet.etherT
    61 TYPE_IPV4: parse_ipv4;
    62 default: accept;
    63 }
    64 }
    65
    66 state parse_ipv4 {
    67 packet.extract(hdr.ipv4);
    68 transition accept;
    69 }
    70
    71 }
    

    View Slide

23. σύʔα
    w ύέοτͷϔομΛॻ͖׵͑Δ෦෼
    w σύʔε͢Δύέοτ͸QBDLFU@PVUͱͯ͠౉͞ΕΔ
    w FNJUϝιουΛ༻͍ͯϔομߏ଄ମ͔ΒϔομΛ૊Έཱ͍ͯͯ͘
    w ֎ଆͷϔομ͔ΒFNJUϝιουΛݺͼग़͍ͯ͘͠
    w ϔομʹ͸WBMJEϑϥά͕͋Γ

    WBMJEͳ΋ͷͷΈ͕ॻ͖ग़͞ΕΔ
    w WBMJEϑϥά͸ύʔα΍ޙड़͢Δ

    ϚονΞΫγϣϯύΠϓϥΠϯ

    Ͱߋ৽͞ΕΔ
    23
    158 control MyDeparser(packet_out packet,
    in headers hdr) {
    159 apply {
    160 packet.emit(hdr.ethernet);
    161 packet.emit(hdr.ipv4);
    162 }
    163 }
    

    View Slide

24. FYUSBDUͱFNJU
    24
    packet.extract(hdr.ethernet);
    packet.extract(hdr.ipv4);
    IFBEFST
    FUIFSOFU@U
    JQW@U QBDLFU@JO
    0010101101010111010101110101111010
    ˣΧʔιϧ
    QBDLFU@JO
    0010101101010111010101110101111010
    ˣΧʔι
    IFBEFST
    FUIFSOFU@U
    JQW@U
    00101011...
    11010101... ✔WBMJE
    ✔WBMJE
    QBDLFU@JO
    0010101101010111010101110101111010
    ˣΧʔιϧ
    IFBEFST
    FUIFSOFU@U
    JQW@U
    00101011... ✔WBMJE
    

    View Slide

25. FYUSBDUͱFNJU
    25
    QBDLFU@PVU
    0010101101010111010101110101111010
    ˣΧʔιϧ
    packet.emit(hdr.ethernet);
    packet.emit(hdr.ipv4);
    QBDLFU
    111010
    ˣΧʔι
    IFBEFST
    FUIFSOFU@U
    JQW@U
    00101011...
    11010101... ✔WBMJE
    ✔WBMJE
    QBDLFU@PVU
    11010101110101111010
    ˣΧʔιϧ
    IFBEFST
    FUIFSOFU@U
    JQW@U
    00101011...
    11010101... ✔WBMJE
    ✔WBMJE
    IFBEFST
    FUIFSOFU@U
    JQW@U
    00101011...
    11010101... ✔WBMJE
    ✔WBMJE
    ˞FNJUͱ͸ٯॱͰWBMJEͳ΋ͷΛੵΜͰ͍͘
    

    View Slide

26. MPPLBIFBEͱBEWBODF
    26
    hdr.ethernet =
    packet.lookahead();
    packet.advance(14);
    IFBEFST
    FUIFSOFU@U
    JQW@U QBDLFU@JO
    0010101101010111010101110101111010
    ˣΧʔιϧ
    QBDLFU@JO
    0010101101010111010101110101111010
    ˣΧʔιϧ
    IFBEFST
    FUIFSOFU@U
    JQW@U
    00101011... ✔WBMJE
    QBDLFU@JO
    0010101101010111010101110101111010
    ˣΧʔιϧ
    IFBEFST
    FUIFSOFU@U
    JQW@U
    00101011... ✔WBMJE
    

    View Slide

27. ϚονΞΫγϣϯύΠϓϥΠϯ
    w ύʔαͰղੳͨ͠ϔομ৘ใ͔ΒςʔϒϧΛ୳ࡧ͠Ϛονͨ͠ΞΫγϣ
    ϯΛ࣮ߦ͢Δͱ͍͏Ұ࿈ͷॲཧͷྲྀΕΛهड़ͨ͠΋ͷ
    w BQQMZ
    w NBJOؔ਺ͷΑ͏ͳ΋ͷ
    w ςʔϒϧͷBQQMZ
    ϝιουΛ

    ݺͼग़͢͜ͱͰϔομ৘ใ͔Β

    ΞΫγϣϯΛݺͼग़͢
    w UBCMF
    w LFZͰͲͷϔομ৘ใ͔Β୳ࡧ

    ͢Δ͔Λఆٛ
    w LFZʹ͸-1.΍&YBDUͳͲͷ

    NBUDI@LJOE ΞʔΩςΫνϟ

    ଆͰఆٛՄೳ
    Λࢦఆ͢Δ
    w BDUJPOTʹ͸ςʔϒϧʹొ࿥͞

    ΕಘΔΞΫγϣϯΛྻڍ
    27
    86 control MyIngress(inout headers hdr,
    87 inout metadata meta,
    88 inout standard_metadata_t s
    ... লུ ...
    93 action ipv4_forward(macAddr_t dstAddr, eg
    94 standard_metadata.egress_spec = port;
    95 hdr.ethernet.srcAddr = hdr.ethernet.d
    96 hdr.ethernet.dstAddr = dstAddr;
    97 hdr.ipv4.ttl = hdr.ipv4.ttl - 1;
    98 }
    100 table ipv4_lpm {
    101 key = {
    102 hdr.ipv4.dstAddr: lpm;
    103 }
    104 actions = {
    105 ipv4_forward;
    106 drop;
    107 NoAction;
    108 }
    109 size = 1024;
    110 default_action = NoAction();
    111 }
    113 apply {
    114 if (hdr.ipv4.isValid()) {
    115 ipv4_lpm.apply();
    116 }
    117 }
    118 }
    

    View Slide

28. ϚονΞΫγϣϯύΠϓϥΠϯ
    w ύʔαͰղੳͨ͠ϔομ৘ใ͔ΒςʔϒϧΛ୳ࡧ͠Ϛονͨ͠ΞΫγϣ
    ϯΛ࣮ߦ͢Δͱ͍͏Ұ࿈ͷॲཧͷྲྀΕΛهड़ͨ͠΋ͷ
    w UBCMF DPOU
    
    w LFZͱBDUJPOT͸ඪ४ςʔϒϧ

    ϓϩύςΟ
    w FOUSJFTͰఆ਺هड़΋Մೳ
    w EFGBVMU@BDUJPO͸Φϓγϣφϧ

    ςʔϒϧϓϩύςΟ
    w ͦΕҎ֎͸ΞʔΩςΫνϟґଘ
    w BDUJPO
    w ςʔϒϧʹϚονͨ࣌͠ʹݺͼ

    ग़͞ΕΔؔ਺ͷΑ͏ͳ΋ͷ
    w Ҿ਺ʹ͸ςʔϒϧʹ֨ೲ͞Εͨ

    ஋͕༻͍ΒΕΔ
    28
    86 control MyIngress(inout headers hdr,
    87 inout metadata meta,
    88 inout standard_metadata_t s
    ... লུ ...
    93 action ipv4_forward(macAddr_t dstAddr, eg
    94 standard_metadata.egress_spec = port;
    95 hdr.ethernet.srcAddr = hdr.ethernet.d
    96 hdr.ethernet.dstAddr = dstAddr;
    97 hdr.ipv4.ttl = hdr.ipv4.ttl - 1;
    98 }
    100 table ipv4_lpm {
    101 key = {
    102 hdr.ipv4.dstAddr: lpm;
    103 }
    104 actions = {
    105 ipv4_forward;
    106 drop;
    107 NoAction;
    108 }
    109 size = 1024;
    110 default_action = NoAction();
    111 }
    113 apply {
    114 if (hdr.ipv4.isValid()) {
    115 ipv4_lpm.apply();
    116 }
    117 }
    118 }
    

    View Slide

29. ϚονΞΫγϣϯύΠϓϥΠϯ
    w .Z*OHSFTTͷྫͰ͸ҎԼͷॲཧ͕ߦΘΕΔ
    w ϔομͷIESJQW͕WBMJEͩͬͨΒETU"EESΛΩʔʹJQW@MQNςʔ
    ϒϧΛ୳ࡧ
    w ΋͠Ϛον͢ΔΤϯτϦʔ͕ଘࡏͨ͠ͳΒͦͷΞΫγϣϯΛొ࿥
    ͞ΕͨҾ਺Ͱݺͼग़͢
    w ͳ͚Ε͹EFGBVMU@BDUJPOͰ͋Δ/P"DUJPOΛݺͼग़͢
    w Ͱɺ͜ͷςʔϒϧ͸Ͳ͏΍ͬͯ؅ཧ͢Δͷʁʁʁ
    29
    table ipv4_lpm
    IESJQWETU"EES ΞΫγϣϯ Ҿ਺
    JQW@GPSXBSE ETU"EESEEC QPSU
    JQW@GPSXBSE ETU"EESEEC QPSU
    

    View Slide

30. ࢀߟ
    13VOUJNF"1*
    30
    Copyright © 2017 – P4.org
    Control plane
    What is P4Runtime?
    • Framework for runtime control of P4 targets
    ◦ Open-source API + server implementation
    ■ https://github.com/p4lang/PI
    ◦ Initial contribution by Google and Barefoot
    • Work-in-progress by the p4.org API WG
    • Protobuf-based API definition
    ◦ p4runtime.proto
    ◦ gRPC as a possible RPC transport
    • P4 program-independent
    ◦ API doesn’t change with the P4 program
    • Enables field-reconfigurability
    ◦ Ability to push new P4 program without recompiling
    deployed switches
    46
    p4runtime.proto
    (API)
    Program-independent
    server (e.g. gRPC)
    Target driver
    P4 target
    l1-BOHVBHF5VUPSJBMzIUUQTHJUIVCDPNQMBOHUVUPSJBMTSBXNBTUFS
    1%@@'BMM1@UVUPSJBM@MBCTQEG͔ΒҾ༻
    

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31. ࢀߟ
    13VOUJNF"1*
    31
    Copyright © 2017 – P4.org
    More details on the P4Runtime API
    47
    Full protobuf definition:
    https://github.com/p4lang/PI/blob/master/proto/p4/p4runtime.proto
    message TableEntry {
    uint32 table_id;
    repeated FieldMatch match;
    Action action;
    int32 priority;
    ...
    }
    message FieldMatch {
    uint32 field_id;
    message Exact {
    bytes value;
    }
    message Ternary {
    bytes value;
    bytes mask;
    }
    ...
    oneof field_match_type {
    Exact exact;
    Ternary ternary;
    ...
    }
    }
    message Action {
    uint32 action_id;
    message Param {
    uint32 param_id;
    bytes value;
    }
    repeated Param params;
    }
    p4runtime.proto simplified excerpts:
    To add a table entry, the control
    plane needs to know:
    • IDs of P4 entities
    ◦ Tables, field matches, actions,
    params, etc.
    • Field matches for the
    particular table
    ◦ Match type, bitwidth, etc.
    • Parameters for the particular
    action
    • Other P4 program attributes
    l1-BOHVBHF5VUPSJBMzIUUQTHJUIVCDPNQMBOHUVUPSJBMTSBXNBTUFS
    1%@@'BMM1@UVUPSJBM@MBCTQEG͔ΒҾ༻
    

    View Slide

32. ࢀߟ
    13VOUJNF"1*
    32
    Copyright © 2017 – P4.org
    P4Runtime workflow
    48
    test.p4
    test.json
    Control plane
    p4runtime.proto
    P4Runtime server
    BMv2 driver
    BMv2
    simple_switch
    p4c-bm2-ss
    (compiler)
    P4Info
    • Captures P4 program attributes
    needed at runtime
    ◦ IDs for tables, actions, params, etc.
    ◦ Table structure, action parameters, etc.
    • Protobuf-based format
    • Target-independent compiler output
    ◦ Same P4Info for BMv2, ASIC, etc.
    test.p4info
    Full P4Info protobuf specification:
    https://github.com/p4lang/PI/blob/master/proto/p4/config/p4info.proto
    l1-BOHVBHF5VUPSJBMzIUUQTHJUIVCDPNQMBOHUVUPSJBMTSBXNBTUFS
    1%@@'BMM1@UVUPSJBM@MBCTQEG͔ΒҾ༻
    

    View Slide

33. ࢀߟ
    13VOUJNF"1*
    33
    Copyright © 2017 – P4.org
    P4Info example
    49
    ...
    action ipv4_forward(bit<48> dstAddr,
    bit<9> port) {
    /* Action implementation */
    }
    ...
    table ipv4_lpm {
    key = {
    hdr.ipv4.dstAddr: lpm;
    }
    actions = {
    ipv4_forward;
    ...
    }
    ...
    }
    basic_router.p4
    actions {
    id: 16786453
    name: "ipv4_forward"
    params {
    id: 1
    name: "dstAddr"
    bitwidth: 48
    ...
    id: 2
    name: "port"
    bitwidth: 9
    }
    }
    ...
    tables {
    id: 33581985
    name: "ipv4_lpm"
    match_fields {
    id: 1
    name: "hdr.ipv4.dstAddr"
    bitwidth: 32
    match_type: LPM
    }
    action_ref_id: 16786453
    }
    basic_router.p4info
    P4 compiler
    l1-BOHVBHF5VUPSJBMzIUUQTHJUIVCDPNQMBOHUVUPSJBMTSBXNBTUFS
    1%@@'BMM1@UVUPSJBM@MBCTQEG͔ΒҾ༻
    

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34. ࢀߟ
    13VOUJNF"1*
    34
    Copyright © 2017 – P4.org
    P4Runtime example
    50
    table_entry {
    table_id: 33581985
    match {
    field_id: 1
    lpm {
    value: "\n\000\002\002"
    prefix_len: 32
    }
    }
    action {
    action_id: 16786453
    params {
    param_id: 1
    value: "\000\000\000\000\000\n"
    }
    params {
    param_id: 2
    value: "\000\007"
    }
    }
    }
    action ipv4_forward(bit<48> dstAddr,
    bit<9> port) {
    /* Action implementation */
    }
    table ipv4_lpm {
    key = {
    hdr.ipv4.dstAddr: lpm;
    }
    actions = {
    ipv4_forward;
    ...
    }
    ...
    }
    hdr.ipv4.dstAddr=10.0.1.1/32
    -> ipv4_forward(00:00:00:00:00:10, 7)
    basic_router.p4
    Logical view of table entry
    Protobuf message
    Control plane
    generates
    l1-BOHVBHF5VUPSJBMzIUUQTHJUIVCDPNQMBOHUVUPSJBMTSBXNBTUFS
    1%@@'BMM1@UVUPSJBM@MBCTQEG͔ΒҾ༻
    

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35. ࢀߟ
    13VOUJNF"1*
    35
    Copyright © 2017 – P4.org
    Remote control
    51
    P4Runtime
    control server
    Target driver
    Vendor A
    P4Runtime
    control server
    Target driver
    Vendor B
    P4Runtime
    control server
    Target driver
    Vendor C
    Remote control plane
    OSPF BGP
    P4-defined
    custom protocol
    etc.
    table_entry {
    table_id: 33581985
    match {
    field_id: 1
    lpm {
    value: "\f\000\...
    prefix_len: 8
    }
    }
    action {
    action_id: 16786453
    params {
    param_id: 1
    value: "\000\0...
    }
    params {
    param_id: 2
    value: 7
    }
    }
    }
    Target-independent
    protobuf format
    p4info p4info p4info
    p4info
    l1-BOHVBHF5VUPSJBMzIUUQTHJUIVCDPNQMBOHUVUPSJBMTSBXNBTUFS
    1%@@'BMM1@UVUPSJBM@MBCTQEG͔ΒҾ༻
    

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36. ࢀߟ
    13VOUJNF"1*
    36
    Copyright © 2017 – P4.org
    Local control
    52
    P4Runtime
    control server
    Target driver
    P4 target
    Local control plane
    OSPF BGP
    P4-defined
    protocol
    etc.
    table_entry {
    table_id: 33581985
    match {
    field_id: 1
    lpm {
    value: "\f\000\...
    prefix_len: 8
    }
    }
    action {
    action_id: 16786453
    params {
    param_id: 1
    value: "\000\0...
    }
    params {
    param_id: 2
    value: 7
    }
    }
    }
    Same
    target-independent
    protobuf format
    p4info
    p4info
    The P4 Runtime API can be used equally well
    by a remote or local control plane
    l1-BOHVBHF5VUPSJBMzIUUQTHJUIVCDPNQMBOHUVUPSJBMTSBXNBTUFS
    1%@@'BMM1@UVUPSJBM@MBCTQEG͔ΒҾ༻
    

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37. ·ͱΊ
    w ϗϫΠτϘοΫεεΠονͷσʔλϓϨʔϯΛࣗ༝ʹΧελϚΠζͰ
    ͖ΔΑ͏ʹͳΔ࣌୅͕དྷΔ͔΋
    w ͨͩ͠1PSUBCMF4XJUDI"SDIJUFDUVSFͱ3VOUJNF"1*͕ඪ४Խ͞
    Εͯ४ڌ͢Δ૷ஔ͕ग़ճ͖ͬͯͨΒʁ
    w 3VOUJNF"1*Λ࢖͑͹0QFO'MPXͰ΍ͬͯͨΑ͏ͳ͜ͱ΋Ͱ͖ͦ͏
    w ͱ͸͍͏΋ͷͷϑϧεΫϥον࣮૷͸͠ΜͲ͍ͷͰ1PSUBCMF4XJUDI
    "SDIJUFDUVSF޲͚ͷΧελϚΠζ༻-εΠον࣮૷͕ग़ͯདྷΔʁ
    w ͋ͱ͸ػثϝʔΧʔ͕ͲΕ͚ͩ৐ͬͯ͘ΕΔ͔ʜ
    w 0QFO'MPXΈ͍ͨʹόζͬͨΒ͋Δ͍͸ʜ
    37
    Πϥετ $
    ͍Β͢ͱ΍
    

    View Slide

38. ࢀߟ৘ใ
    w 1-BOHVBHF$POTPSUJVN
    w IUUQTQPSH
    w 1-BOHVBHF4QFDJpDBUJPO
    w IUUQTQMBOHHJUIVCJPQTQFDEPDT1WTQFDIUNM
    w 11PSUBCMF4XJUDI"SDIJUFDUVSF 14"
    
    w IUUQTQPSHQTQFDEPDT14"IUNM
    w 1%FWFMPQFS%BZ 1%
    'BMM
    w IUUQTXXXZPVUVCFDPNQMBZMJTU MJTU1-G)(3."M+#[($(D:QJNZ*T%OV4PP
    w 1-BOHVBHF5VUPSJBM
    w IUUQTHJUIVCDPNQMBOHUVUPSJBMTSBXNBTUFS1%@@'BMM
    1@UVUPSJBM@MBCTQEG
    w 1QSPUPUZQFDPNQJMFS
    w IUUQTHJUIVCDPNQMBOHQD
    w 3FXSJUFPGUIFCFIBWJPSBMNPEFMBTB$QSPKFDUXJUIPVUBVUPHFOFSBUFEDPEF
    FYDFQUGPSUIF1%JOUFSGBDF
    
    w IUUQTHJUIVCDPNQMBOHCFIBWJPSBMNPEFM
    w 13VOUJNFBDPOUSPMQMBOFGSBNFXPSLBOEUPPMTGPSUIF1QSPHSBNNJOHMBOHVBHF
    w IUUQTHJUIVCDPNQMBOH1*
    38
    

    View Slide