ROHC compression/decompression library: feedback.h Source File

00001 /*
00002  * Copyright 2015,2016 Didier Barvaux
00003  *
00004  * This library is free software; you can redistribute it and/or
00005  * modify it under the terms of the GNU Lesser General Public
00006  * License as published by the Free Software Foundation; either
00007  * version 2.1 of the License, or (at your option) any later version.
00008  *
00009  * This library is distributed in the hope that it will be useful,
00010  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00011  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00012  * Lesser General Public License for more details.
00013  *
00014  * You should have received a copy of the GNU Lesser General Public
00015  * License along with this library; if not, write to the Free Software
00016  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
00017  */
00018 
00019 /**
00020  * @file   feedback.h
00021  * @brief  ROHC feedback definitions and formats
00022  * @author Didier Barvaux <didier@barvaux.org>
00023  */
00024 
00025 #ifndef ROHC_FEEDBACK_H
00026 #define ROHC_FEEDBACK_H
00027 
00028 #include "rohc.h"
00029 
00030 #ifdef __KERNEL__
00031 #  include <endian.h>
00032 #else
00033 #  include "config.h" /* for WORDS_BIGENDIAN */
00034 #endif
00035 
00036 #include <stdbool.h>
00037 #include <stdint.h>
00038 #include <stddef.h>
00039 
00040 
00041 /** The type of ROHC feedback */
00042 enum rohc_feedback_type
00043 {
00044         ROHC_FEEDBACK_1 = 1,  /**< ROHC FEEDBACK-1 */
00045         ROHC_FEEDBACK_2 = 2,  /**< ROHC FEEDBACK-2 */
00046 };
00047 
00048 
00049 /** The type of acknowledgement */
00050 enum rohc_feedback_ack_type
00051 {
00052         ROHC_FEEDBACK_ACK         = 0, /**< The classical ACKnowledgement */
00053         ROHC_FEEDBACK_NACK        = 1, /**< The Negative ACKnowledgement */
00054         ROHC_FEEDBACK_STATIC_NACK = 2, /**< The Negative STATIC ACKnowledgement */
00055         ROHC_FEEDBACK_RESERVED    = 3, /**< reserved (MUST NOT be used for parsability) */
00056 };
00057 
00058 
00059 /** The ROHC feedback options */
00060 enum rohc_feedback_opt
00061 {
00062         ROHC_FEEDBACK_OPT_CRC            =  1, /**< The Feedback CRC option */
00063         ROHC_FEEDBACK_OPT_REJECT         =  2, /**< The Feedback REJECT option */
00064         ROHC_FEEDBACK_OPT_SN_NOT_VALID   =  3, /**< The Feedback SN-NOT-VALID option */
00065 /** The Feedback MSN-NOT-VALID option (TCP profile) */
00066 #define ROHC_FEEDBACK_OPT_MSN_NOT_VALID ROHC_FEEDBACK_OPT_SN_NOT_VALID
00067         ROHC_FEEDBACK_OPT_SN             =  4, /**< The Feedback SN option */
00068 /** The Feedback MSN option (TCP profile) */
00069 #define ROHC_FEEDBACK_OPT_MSN ROHC_FEEDBACK_OPT_SN
00070         ROHC_FEEDBACK_OPT_CLOCK          =  5, /**< The Feedback CLOCK option */
00071         ROHC_FEEDBACK_OPT_JITTER         =  6, /**< The Feedback JITTER option */
00072         ROHC_FEEDBACK_OPT_LOSS           =  7, /**< The Feedback LOSS option */
00073         ROHC_FEEDBACK_OPT_CV_REQUEST     =  8, /**< The Feedback CV-REQUEST option */
00074         ROHC_FEEDBACK_OPT_CONTEXT_MEMORY =  9, /**< The Feedback CONTEXT_MEMORY option */
00075         ROHC_FEEDBACK_OPT_UNKNOWN_10     = 10, /**< Unknown option with value 10 */
00076         ROHC_FEEDBACK_OPT_UNKNOWN_11     = 11, /**< Unknown option with value 11 */
00077         ROHC_FEEDBACK_OPT_UNKNOWN_12     = 12, /**< Unknown option with value 12 */
00078         ROHC_FEEDBACK_OPT_UNKNOWN_13     = 13, /**< Unknown option with value 13 */
00079         ROHC_FEEDBACK_OPT_UNKNOWN_14     = 14, /**< Unknown option with value 14 */
00080         ROHC_FEEDBACK_OPT_UNKNOWN_15     = 15, /**< Unknown option with value 15 */
00081         ROHC_FEEDBACK_OPT_MAX                  /**< The max number of feedback options */
00082 };
00083 
00084 
00085 /** The ROHC FEEDBACK-2 format as defined in RFC3095 */
00086 struct rohc_feedback_2_rfc3095
00087 {
00088 #if WORDS_BIGENDIAN == 1
00089         uint8_t ack_type:2; /**< The type of acknowledgement \see rohc_feedback_ack_type */
00090         uint8_t mode:2;     /**< The decompression context mode */
00091         uint8_t sn1:4;      /**< The 4 first LSB bits of the SN being acked */
00092 #else
00093         uint8_t sn1:4;
00094         uint8_t mode:2;
00095         uint8_t ack_type:2;
00096 #endif
00097         uint8_t sn2;        /**< The 8 next  LSB bits of the SN being acked */
00098 } __attribute__((packed));
00099 
00100 
00101 /** The ROHC FEEDBACK-2 format as defined in RFC6846 */
00102 struct rohc_feedback_2_rfc6846
00103 {
00104 #if WORDS_BIGENDIAN == 1
00105         uint8_t ack_type:2; /**< The type of acknowledgement \see rohc_feedback_ack_type */
00106         uint8_t sn1:6;      /**< The 6 first LSB bits of the SN being acked */
00107 #else
00108         uint8_t sn1:6;
00109         uint8_t ack_type:2;
00110 #endif
00111         uint8_t sn2;        /**< The 8 next  LSB bits of the SN being acked */
00112         uint8_t crc;        /**< The feedback CRC */
00113 } __attribute__((packed));
00114 
00115 
00116 /** The characteristics of one ROHC feedback option */
00117 struct rohc_feedback_opt_charac
00118 {
00119         const char *const name;
00120         bool unknown;
00121         bool supported;
00122         size_t expected_len;
00123         enum {
00124                 ROHC_FEEDBACK_OPT_CRC_REQUIRED,
00125                 ROHC_FEEDBACK_OPT_CRC_SUGGESTED,
00126                 ROHC_FEEDBACK_OPT_CRC_NOT_REQUIRED,
00127         } crc_req;
00128         size_t max_occurs[ROHC_PROFILE_MAX];
00129 };
00130 
00131 
00132 /**
00133  * @brief Max occurrences of a feedback option in one feedback packet
00134  *
00135  * Even if the standard says that some options may be present multiple times,
00136  * don't allow more than a raisonable occurrences. It allows the library to
00137  * protect itself against abuses.
00138  */
00139 #define ROHC_FEEDBACK_OPT_MAX_OCCURS  100U
00140 
00141 
00142 /** Feedback options capacities */
00143 static const struct rohc_feedback_opt_charac
00144         rohc_feedback_opt_charac[ROHC_FEEDBACK_OPT_MAX] =
00145 {
00146         [0]                        = {
00147                 .name = "unknown option with value 0",
00148                 .unknown = true,
00149         },
00150         [ROHC_FEEDBACK_OPT_CRC]    = {
00151                 .name = "CRC",
00152                 .unknown = false,
00153                 .supported = true,
00154                 .expected_len = 2U,
00155                 .crc_req = ROHC_FEEDBACK_OPT_CRC_NOT_REQUIRED,
00156                 .max_occurs = {
00157                         [ROHC_PROFILE_UNCOMPRESSED] = 0, /* RFC3095 §5.10.4 */
00158                         [ROHC_PROFILE_RTP]          = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* RFC3095 §5.7.6.3 */
00159                         [ROHC_PROFILE_UDP]          = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00160                         [ROHC_PROFILE_ESP]          = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as UDP */
00161                         [ROHC_PROFILE_IP]           = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as UDP */
00162                         [ROHC_PROFILE_RTP_LLA]      = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00163                         [ROHC_PROFILE_TCP]          = 0, /* RFC6846 §8.3.2 */
00164                         [ROHC_PROFILE_UDPLITE_RTP]  = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00165                         [ROHC_PROFILE_UDPLITE]      = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as UDP */
00166                 }
00167         },
00168         [ROHC_FEEDBACK_OPT_REJECT] = {
00169                 .name = "REJECT",
00170                 .unknown = false,
00171                 .supported = true,
00172                 .expected_len = 1U,
00173                 .crc_req = ROHC_FEEDBACK_OPT_CRC_REQUIRED, /* RFC3095, §5.7.6.4 */
00174                 .max_occurs = {
00175                         [ROHC_PROFILE_UNCOMPRESSED] = 0, /* RFC3095 §5.10.4 */
00176                         [ROHC_PROFILE_RTP]          = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* RFC3095 §5.7.6.4 */
00177                         [ROHC_PROFILE_UDP]          = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00178                         [ROHC_PROFILE_ESP]          = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as UDP */
00179                         [ROHC_PROFILE_IP]           = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as UDP */
00180                         [ROHC_PROFILE_RTP_LLA]      = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00181                         [ROHC_PROFILE_TCP]          = 1, /* RFC6846 §8.3.2.1 */
00182                         [ROHC_PROFILE_UDPLITE_RTP]  = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00183                         [ROHC_PROFILE_UDPLITE]      = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as UDP */
00184                 }
00185         },
00186         [ROHC_FEEDBACK_OPT_SN_NOT_VALID] = {
00187                 .name = "(M)SN-NOT-VALID",
00188                 .unknown = false,
00189                 .supported = true,
00190                 .expected_len = 1U,
00191                 .crc_req = ROHC_FEEDBACK_OPT_CRC_NOT_REQUIRED,
00192                 .max_occurs = {
00193                         [ROHC_PROFILE_UNCOMPRESSED] = 0, /* RFC3095 §5.10.4 */
00194                         [ROHC_PROFILE_RTP]          = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* RFC3095 §5.7.6.5 */
00195                         [ROHC_PROFILE_UDP]          = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00196                         [ROHC_PROFILE_ESP]          = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as UDP */
00197                         [ROHC_PROFILE_IP]           = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as UDP */
00198                         [ROHC_PROFILE_RTP_LLA]      = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00199                         [ROHC_PROFILE_TCP]          = 1, /* RFC6846 §8.3.2.2 */
00200                         [ROHC_PROFILE_UDPLITE_RTP]  = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00201                         [ROHC_PROFILE_UDPLITE]      = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as UDP */
00202                 }
00203         },
00204         [ROHC_FEEDBACK_OPT_SN] = {
00205                 .name = "(M)SN",
00206                 .unknown = false,
00207                 .supported = true,
00208                 .expected_len = 2U,
00209                 .crc_req = ROHC_FEEDBACK_OPT_CRC_NOT_REQUIRED,
00210                 .max_occurs = {
00211                         [ROHC_PROFILE_UNCOMPRESSED] = 0, /* RFC3095 §5.10.4 */
00212                         [ROHC_PROFILE_RTP]          = 1, /* RFC4815 §8.5: 1 option needed for 16-bit SN */
00213                         [ROHC_PROFILE_UDP]          = 1, /* same as RTP */
00214                         [ROHC_PROFILE_ESP]          = 3, /* RFC4815 §8.5: 3 options needed for 32-bit SN */
00215                         [ROHC_PROFILE_IP]           = 1, /* same as UDP */
00216                         [ROHC_PROFILE_RTP_LLA]      = 1, /* same as RTP */
00217                         [ROHC_PROFILE_TCP]          = 1, /* RFC6846 §8.3.2.3 */
00218                         [ROHC_PROFILE_UDPLITE_RTP]  = 1, /* same as RTP */
00219                         [ROHC_PROFILE_UDPLITE]      = 1, /* same as UDP */
00220                 }
00221         },
00222         [ROHC_FEEDBACK_OPT_CLOCK] = {
00223                 .name = "CLOCK",
00224                 .unknown = false,
00225                 .supported = false,
00226                 .expected_len = 2U,
00227                 .crc_req = ROHC_FEEDBACK_OPT_CRC_SUGGESTED, /* RFC3095, §5.7.6.7 */
00228                 .max_occurs = {
00229                         [ROHC_PROFILE_UNCOMPRESSED] = 0, /* RFC3095 §5.10.4 */
00230                         [ROHC_PROFILE_RTP]          = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* RFC3095 §5.7.6.7 */
00231                         [ROHC_PROFILE_UDP]          = 0, /* RFC3095 §5.11.6 */
00232                         [ROHC_PROFILE_ESP]          = 0, /* same as UDP */
00233                         [ROHC_PROFILE_IP]           = 0, /* same as UDP */
00234                         [ROHC_PROFILE_RTP_LLA]      = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00235                         [ROHC_PROFILE_TCP]          = 0, /* RFC6846 §8.3.2 */
00236                         [ROHC_PROFILE_UDPLITE_RTP]  = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00237                         [ROHC_PROFILE_UDPLITE]      = 0, /* same as UDP */
00238                 }
00239         },
00240         [ROHC_FEEDBACK_OPT_JITTER] = {
00241                 .name = "JITTER",
00242                 .unknown = false,
00243                 .supported = false,
00244                 .expected_len = 2U,
00245                 .crc_req = ROHC_FEEDBACK_OPT_CRC_SUGGESTED, /* RFC3095, §5.7.6.8 */
00246                 .max_occurs = {
00247                         [ROHC_PROFILE_UNCOMPRESSED] = 0, /* RFC3095 §5.10.4 */
00248                         [ROHC_PROFILE_RTP]          = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* RFC3095 §5.7.6.8 */
00249                         [ROHC_PROFILE_UDP]          = 0, /* RFC3095 §5.11.6 */
00250                         [ROHC_PROFILE_ESP]          = 0, /* same as UDP */
00251                         [ROHC_PROFILE_IP]           = 0, /* same as UDP */
00252                         [ROHC_PROFILE_RTP_LLA]      = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00253                         [ROHC_PROFILE_TCP]          = 0, /* RFC6846 §8.3.2 */
00254                         [ROHC_PROFILE_UDPLITE_RTP]  = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00255                         [ROHC_PROFILE_UDPLITE]      = 0, /* same as UDP */
00256                 }
00257         },
00258         [ROHC_FEEDBACK_OPT_LOSS] = {
00259                 .name = "LOSS",
00260                 .unknown = false,
00261                 .supported = false,
00262                 .expected_len = 2U,
00263                 .crc_req = ROHC_FEEDBACK_OPT_CRC_SUGGESTED, /* RFC3095, §5.7.6.9 */
00264                 .max_occurs = {
00265                         [ROHC_PROFILE_UNCOMPRESSED] = 0, /* RFC3095 §5.10.4 */
00266                         [ROHC_PROFILE_RTP]          = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* RFC3095 §5.7.6.9 */
00267                         [ROHC_PROFILE_UDP]          = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00268                         [ROHC_PROFILE_ESP]          = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as UDP */
00269                         [ROHC_PROFILE_IP]           = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as UDP */
00270                         [ROHC_PROFILE_RTP_LLA]      = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00271                         [ROHC_PROFILE_TCP]          = 0, /* RFC6846 §8.3.2 */
00272                         [ROHC_PROFILE_UDPLITE_RTP]  = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as RTP */
00273                         [ROHC_PROFILE_UDPLITE]      = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* same as UDP */
00274                 }
00275         },
00276         [ROHC_FEEDBACK_OPT_CV_REQUEST] = {
00277                 .name = "CV-REQUEST",
00278                 .unknown = false,
00279                 .supported = false,
00280                 .expected_len = 1U,
00281                 .crc_req = ROHC_FEEDBACK_OPT_CRC_NOT_REQUIRED,
00282                 .max_occurs = {
00283                         [ROHC_PROFILE_UNCOMPRESSED] = 0, /* RFC3095 §5.10.4 */
00284                         [ROHC_PROFILE_RTP]          = 0, /* RFC3095 §5.7.6.2 */
00285                         [ROHC_PROFILE_UDP]          = 0, /* same as RTP */
00286                         [ROHC_PROFILE_ESP]          = 0, /* same as UDP */
00287                         [ROHC_PROFILE_IP]           = 0, /* same as UDP */
00288                         [ROHC_PROFILE_RTP_LLA]      = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* RFC4362 §4.5 */
00289                         [ROHC_PROFILE_TCP]          = 0, /* RFC6846 §8.3.2 */
00290                         [ROHC_PROFILE_UDPLITE_RTP]  = 0, /* same as RTP */
00291                         [ROHC_PROFILE_UDPLITE]      = 0, /* same as UDP */
00292                 }
00293         },
00294         [ROHC_FEEDBACK_OPT_CONTEXT_MEMORY] = {
00295                 .name = "CONTEXT_MEMORY",
00296                 .unknown = false,
00297                 .supported = false,
00298                 .expected_len = 1U,
00299                 .crc_req = ROHC_FEEDBACK_OPT_CRC_NOT_REQUIRED,
00300                 .max_occurs = {
00301                         [ROHC_PROFILE_UNCOMPRESSED] = 0, /* RFC3095 §5.10.4 */
00302                         [ROHC_PROFILE_RTP]          = 0, /* RFC3095 §5.7.6.2 */
00303                         [ROHC_PROFILE_UDP]          = 0, /* same as RTP */
00304                         [ROHC_PROFILE_ESP]          = 0, /* same as UDP */
00305                         [ROHC_PROFILE_IP]           = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* RFC3843 §3.7 */
00306                         [ROHC_PROFILE_RTP_LLA]      = 0, /* same as RTP */
00307                         [ROHC_PROFILE_TCP]          = 1, /* RFC6846 §8.3.2.4 */
00308                         [ROHC_PROFILE_UDPLITE_RTP]  = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* RFC4019 §5.7 */
00309                         [ROHC_PROFILE_UDPLITE]      = ROHC_FEEDBACK_OPT_MAX_OCCURS, /* RFC4019 §5.7 */
00310                 }
00311         },
00312         [ROHC_FEEDBACK_OPT_UNKNOWN_10] = {
00313                 .name = "unknown option with value 10",
00314                 .unknown = true,
00315         },
00316         [ROHC_FEEDBACK_OPT_UNKNOWN_11] = {
00317                 .name = "unknown option with value 11",
00318                 .unknown = true,
00319         },
00320         [ROHC_FEEDBACK_OPT_UNKNOWN_12] = {
00321                 .name = "unknown option with value 12",
00322                 .unknown = true,
00323         },
00324         [ROHC_FEEDBACK_OPT_UNKNOWN_13] = {
00325                 .name = "unknown option with value 13",
00326                 .unknown = true,
00327         },
00328         [ROHC_FEEDBACK_OPT_UNKNOWN_14] = {
00329                 .name = "unknown option with value 14",
00330                 .unknown = true,
00331         },
00332         [ROHC_FEEDBACK_OPT_UNKNOWN_15] = {
00333                 .name = "unknown option with value 15",
00334                 .unknown = true,
00335         },
00336 };
00337 
00338 
00339 #endif
00340