Changeset aa22b5b


Ignore:
Timestamp:
10/31/08 13:51:59 (14 years ago)
Author:
Perry Lorier <perry@…>
Branches:
4.0.1-hotfixes, cachetimestamps, develop, dpdk-ndag, etsilive, getfragoff, help, libtrace4, master, ndag_format, pfring, rc-4.0.1, rc-4.0.2, rc-4.0.3, rc-4.0.4, ringdecrementfix, ringperformance, ringtimestampfixes
Children:
13fd6e1
Parents:
5d4e520
Message:

If we have a complete header, but truncated at the end of it, we shouldn't return NULL from
get_payload_from_* functions so we can distinguish it from a truncated header.

Location:
lib
Files:
5 edited

Legend:

Unmodified
Added
Removed

  • lib/libtrace.h.in

    r530cef6 raa22b5b  
    10771077 * wireless monitoring header.
    10781078 *
     1079 * If the header is truncated, this function will return NULL, and remaining will be 0.
     1080 * If there are 0 bytes of payload, the function will return a pointer, and remaining will be 0.
     1081 *
    10791082 * @param[in] meta a pointer to a header
    10801083 * @param[in,out] linktype the linktype of meta (updated to indicate the
    … …  
    10851088 * unchanged.
    10861089 *
    1087  * All parameters are mandatory. NULL will be returned if any are NULL.
     1090 * All parameters are mandatory.
    10881091 */
    10891092DLLEXPORT void *trace_get_payload_from_meta(const void *meta,
    … …  
    11161119 * @param l2                    The pointer to the current layer2 header
    11171120 * @param linktype              The type of the layer2 header
    1118  * @param[out] ethertype        An optional output variable of the ethernet type
    1119  * @param[in,out] remaining     Optionally updated with the length remaining
     1121 * @param[out] ethertype        An optional output variable of the ethernet type of the new header
     1122 * @param[in,out] remaining     Updated with the length remaining
    11201123 *
    11211124 * @return a pointer to the transport layer header, or NULL if header isn't
    11221125 * present.
    11231126 *
    1124  * type may be NULL if not needed.
    1125  *
    1126  * Remaining may be NULL.  If Remaining is not NULL it must point to the number
    1127  * of bytes captured of the layer2 header and beyond.  It will be decremented
    1128  * by the number of bytes skipped to find the payload.
     1127 * Remaining must point to the number of bytes captured of the layer2 header
     1128 * and beyond.  It will be decremented by the number of bytes skipped to find
     1129 * the payload.
     1130 *
     1131 * If the layer2 header is complete but there are zero bytes of payload after the end of the header,
     1132 * a pointer to where the payload would be is returned and remaining will be set to 0.  If the
     1133 * layer2 header is incomplete (truncated), then NULL is returned and remaining will be set to 0.
    11291134 *
    11301135 */
    … …  
    11691174 * present.
    11701175 *
    1171  * Remaining may be NULL.  If Remaining is not NULL it must point to the number
    1172  * of bytes captured of the IP header and beyond.  It will be decremented by
    1173  * the length of the IPv4 header (including any options).
    1174  *
    1175  * proto may be NULL if not needed.
     1176 * Remaining will be decremented by the size of the IPv4 header (including any options).
     1177 * If the IPv4 header is complete but there are zero bytes of payload after the IPv4 header, a pointer
     1178 * to where the payload would be is returned and remaining will be set to 0.  If the IPv4 header is
     1179 * incomplete, NULL will be returned and remaining will be set to 0.
     1180 *
     1181 * proto may be NULL, in which case it won't be updated
    11761182 *
    11771183 * @note This is similar to trace_get_transport_from_ip in libtrace2
    … …  
    11881194 * isn't complete.
    11891195 *
    1190  * Remaining may be NULL.  If Remaining is not NULL it must point to the number
    1191  * of bytes captured of the IP header and beyond.  It will be decremented by
    1192  * this function by the length of the IPV6 header.
    1193  *
    1194  * proto may be NULL if not needed.
     1196 * Remaining will be decremented by the size of the IPv6 header (including any options).
     1197 * If the IPv6 header is complete but there are zero bytes of payload after the IPv6 header, a pointer
     1198 * to where the payload would be is returned and remaining will be set to 0.  If the IPv6 header is
     1199 * incomplete, NULL will be returned and remaining will be set to 0.
     1200 *
     1201 * proto may be NULL, in which case it won't be updated.
    11951202 *
    11961203 */
    … …  
    12181225                uint16_t *type, uint32_t *remaining);
    12191226
    1220 /** Skips over any 802.1q headers, if present.
     1227/** Skips over any 802.1q header, if present.
    12211228 * @param vlan      A pointer to the vlan header
    1222  * @param[in,out] type  The ethernet type, replaced with the vlan ether type
     1229 * @param[out] type  The ethernet type, replaced with the vlan ether type
    12231230 * @param[in,out] remaining Updated with the number of bytes remaining
    12241231 *
    12251232 * @return a pointer to the header beyond the vlan header, if present.
    1226  * Otherwise, returns NULL
    1227  *
    1228  * Remaining may be NULL. If Remaining is not NULL it must point to the number
    1229  * of bytes captured past (but not including) the link layer. This function
    1230  * will decrement it by the length of the 802.1q headers if present.
    1231  *
    1232  * Type must point to the value of the ethernet type. Libtrace will assert
    1233  * fail if type is NULL.
     1233 * Otherwise, returns NULL. 
     1234 *
     1235 * Remaining will be decremented by the size of the vlan header.  If the vlan
     1236 * header is complete but there are zero bytes of payload after the vlan
     1237 * header, a pointer to where the payload would be is returned and remaining
     1238 * will be set to 0.  If the vlan header is incomplete, NULL will be returned
     1239 * and remaining will be set to 0.
     1240 *
     1241 * type will be set to the ethertype contained within the vlan payload.
    12341242 *
    12351243 */
    … …  
    12371245                void *vlan, uint16_t *type, uint32_t *remaining);
    12381246
    1239 /** Skips over any MPLS headers, if present.
     1247/** Skips over a MPLS header
    12401248 * @param mpls      A pointer to the mpls header
    1241  * @param[in,out] type  The ethernet type, replaced by the ether type of the
     1249 * @param[out] type  The ethernet type, replaced by the ether type of the
    12421250 * following header - 0x0000 if an Ethernet header is deemed to be next
    12431251 * @param[in,out] remaining     Updated with the number of bytes remaining
    … …  
    12451253 * @return a pointer to the header beyond the MPLS label, if present. Will
    12461254 * return NULL if there is not enough bytes remaining to skip past the MPLS
    1247  * label or if the ether type is not MPLS.
    1248  *
    1249  * Remaining may be NULL. If remaining is not NULL it must point to the number
    1250  * of bytes captured past (but not including) the link layer. This function
    1251  * will decrement it by the length of the topmost MPLS label if present.
     1255 * label.
     1256 *
     1257 * Remaining will be decremented by the size of the MPLS header.  If the MPLS
     1258 * header is complete but there are zero bytes of payload after the MPLS
     1259 * header, a pointer to where the payload would be is returned and remaining
     1260 * will be set to 0.  If the MPLS header is incomplete, NULL will be returned
     1261 * and remaining will be set to 0.
    12521262 *
    12531263 * Type must point to the value of the ethernet type. Libtrace will assert
    … …  
    12661276 * @param[in,out] remaining Updated with the number of bytes remaining
    12671277 *
    1268  * @return a pointer to the tcp payload, or NULL if the payload isn't present.
    1269  *
    1270  * Remaining may be NULL.  If remaining is not NULL it must point to the number
    1271  * of bytes captured of the TCP header and beyond.  It will be decremented by
    1272  * this function by the length of the TCP header (including any options).
     1278 * @return a pointer to the tcp payload, or NULL if the tcp header is truncated.
     1279 *
     1280 * Remaining will be decremented by the size of the TCP header.  If the TCP
     1281 * header is complete but there are zero bytes of payload after the TCP
     1282 * header, a pointer to where the payload would be is returned and remaining
     1283 * will be set to 0.  If the TCP header is incomplete, NULL will be returned
     1284 * and remaining will be set to 0.
    12731285 *
    12741286 */
    … …  
    12801292 * @param[in,out] remaining Updated with the number of bytes remaining
    12811293 *
    1282  * @return a pointer to the udp payload, or NULL if the payload isn't present.
    1283  *
    1284  * Remaining may be NULL.  If Remaining is not NULL it must point to the number
    1285  * of bytes captured of the UDP header and beyond.  It will be decremented by
    1286  * this function to the number of bytes remaining after the UDP header.
     1294 * @return a pointer to the udp payload, or NULL if the udp header is truncated.
     1295 *
     1296 * Remaining will be decremented by the size of the TCP header.  If the TCP
     1297 * header is complete but there are zero bytes of payload after the TCP
     1298 * header, a pointer to where the payload would be is returned and remaining
     1299 * will be set to 0.  If the TCP header is incomplete, NULL will be returned
     1300 * and remaining will be set to 0.
    12871301 *
    12881302 */
    … …  
    12931307 * @param[in,out] remaining Updated with the number of bytes remaining
    12941308 *
    1295  * @return a pointer to the icmp payload, or NULL if the payload isn't present.
    1296  *
    1297  * Remaining may be NULL.  If remaining is not NULL it must point to the number
    1298  * of bytes captured of the ICMP header and beyond.  It will be decremented
    1299  * by the number of bytes in the ICMP header.
     1309 * @return a pointer to the icmp payload, or NULL if the icmp header is truncated.
     1310 *
     1311 * Remaining will be decremented by the size of the TCP header.  If the TCP
     1312 * header is complete but there are zero bytes of payload after the TCP
     1313 * header, a pointer to where the payload would be is returned and remaining
     1314 * will be set to 0.  If the TCP header is incomplete, NULL will be returned
     1315 * and remaining will be set to 0.
    13001316 *
    13011317 */

  • lib/protocols_l2.c

    r530cef6 raa22b5b  
    1515
    1616        if (remaining) {
    17                 if (*remaining <= sizeof(*eth)) {
     17                if (*remaining < sizeof(*eth)) {
    1818                        *remaining = 0;
    1919                        return NULL;
    … …  
    2929
    3030/* skip any 802.1q headers if necessary
    31  * type is input/output
     31 * type is now output only (why check it if we don't need to?)
    3232 */
    3333void *trace_get_payload_from_vlan(void *ethernet, uint16_t *type,
    3434                uint32_t *remaining)
    3535{
    36         assert(type != NULL);
    37         if (*type == 0x8100) {
    38                 libtrace_8021q_t *vlanhdr = (libtrace_8021q_t *)ethernet;
    39 
    40                 if (remaining) {
    41                         if (*remaining <= sizeof(libtrace_8021q_t)) {
    42                                 *remaining = 0;
    43                                 return NULL;
    44                         }
    45 
    46                         *remaining=*remaining-sizeof(libtrace_8021q_t);
    47                 }
    48 
     36        libtrace_8021q_t *vlanhdr = (libtrace_8021q_t *)ethernet;
     37
     38        if (remaining) {
     39                if (*remaining < sizeof(libtrace_8021q_t)) {
     40                        *remaining = 0;
     41                        return NULL;
     42                }
     43
     44                *remaining=*remaining-sizeof(libtrace_8021q_t);
     45        }
     46
     47        if (type)
    4948                *type = ntohs(vlanhdr->vlan_ether_type);
    5049
    51                 return (void*)((char *)ethernet + sizeof(*vlanhdr));
    52         } else
    53                 return NULL;
     50        return (void*)((char *)ethernet + sizeof(*vlanhdr));
    5451
    5552}
    … …  
    6259                uint32_t *remaining)
    6360{
    64         assert(type != NULL);
    65        
    66         if (*type == 0x8847) {
    67                 if ((((char*)ethernet)[2]&0x01)==0) {
    68                         *type = 0x8847;
    69                 }
    70                 else {
    71                         if (!remaining || *remaining>=5) {
    72                                 switch (((char*)ethernet)[4]&0xF0) {
    73                                         case 0x40:
    74                                                 *type = 0x0800;
    75                                                 break;
    76                                         case 0x60:
    77                                                 *type = 0x86DD;
    78                                                 break;
    79                                         default:
    80                                                 /* Ethernet */
    81                                                 *type = 0;
    82                                 }
     61       
     62        assert(type);
     63        if ((((char*)ethernet)[2]&0x01)==0) {
     64                /* The MPLS Stack bit is set */
     65                *type = 0x8847;
     66        }
     67        else {
     68                if (!remaining || *remaining>=5) {
     69                        switch (((char*)ethernet)[4]&0xF0) {
     70                                case 0x40:      /* IPv4 */
     71                                        *type = 0x0800;
     72                                        break;
     73                                case 0x60:      /* IPv6 */
     74                                        *type = 0x86DD;
     75                                        break;
     76                                default:        /* VPLS */
     77                                        /* Ethernet */
     78                                        *type = 0;
    8379                        }
    8480                }
    85                 ethernet=(char*)ethernet+4;
    86                 if (remaining) {
    87                         if (*remaining<=4)
    88                                 return NULL;
    89                         else
    90                                 *remaining-=4;
    91                 }
    92 
    93 
    94                 return ethernet;
    95         }
    96         else
    97                 return NULL;
     81        }
     82        ethernet=(char*)ethernet+4;
     83        if (remaining) {
     84                if (*remaining<4)
     85                        return NULL;
     86                else
     87                        *remaining-=4;
     88        }
     89
     90
     91        return ethernet;
    9892}
    9993
    … …  
    10599
    106100        if (remaining) {
    107                 if (*remaining <= sizeof(libtrace_llcsnap_t)) {
     101                if (*remaining < sizeof(libtrace_llcsnap_t)) {
    108102                        *remaining = 0;
    109103                        return NULL;
    … …  
    126120        int8_t extra = 0; /* how many QoS bytes to skip */
    127121       
    128         if (remaining && *remaining <= sizeof(libtrace_80211_t)) {
     122        if (remaining && *remaining < sizeof(libtrace_80211_t)) {
    129123                *remaining = 0;
    130124                return NULL;
    … …  
    172166
    173167        if (remaining) {
    174                 if (*remaining <= sizeof(libtrace_ppp_t)) {
     168                if (*remaining < sizeof(libtrace_ppp_t)) {
    175169                        *remaining = 0;
    176170                        return NULL;
    … …  
    196190                uint32_t *remaining) {
    197191        if (remaining) {
    198                 if (*remaining <= sizeof(libtrace_pppoe_t)) {
     192                if (*remaining < sizeof(libtrace_pppoe_t)) {
    199193                        *remaining = 0;
    200194                        return NULL;
    … …  
    221215
    222216        if (remaining) {
    223                 if (*remaining <= sizeof(libtrace_chdlc_t)) {
     217                if (*remaining < sizeof(libtrace_chdlc_t)) {
    224218                        *remaining = 0;
    225219                        return NULL;
    … …  
    245239                if (l != NULL) {
    246240                        link=l;
    247                         continue;
    248                 }
    249         } while (0);
     241                }
     242        } while (l != NULL);
    250243
    251244        return trace_get_payload_from_layer2(link,linktype,ethertype,remaining);
    … …  
    291284{
    292285        libtrace_atm_capture_cell_t *cell;
    293         if (remaining && *remaining<=sizeof(libtrace_atm_capture_cell_t)) {
     286        if (remaining && *remaining<sizeof(libtrace_atm_capture_cell_t)) {
    294287                *remaining = 0;
    295288                return NULL;
    … …  
    338331                case TRACE_TYPE_NONE:
    339332                        if ((*(char*)link&0xF0) == 0x40)
    340                                 *ethertype=0x0800;
     333                                *ethertype=0x0800;      /* IPv4 */
    341334                        else if ((*(char*)link&0xF0) == 0x60)
    342                                 *ethertype=0x86DD;
     335                                *ethertype=0x86DD;      /* IPv6 */
    343336                        return link; /* I love the simplicity */
    344337                case TRACE_TYPE_PPP:

  • lib/protocols_l3.c

    r530cef6 raa22b5b  
    4949        void *trans_ptr = 0;
    5050
    51         if (ipptr == NULL)
    52                 return NULL;
     51        assert(ipptr != NULL);
     52        assert(ipptr->ip_v == 4);
    5353
    5454        if ((ntohs(ipptr->ip_off) & SW_IP_OFFMASK) != 0) {
    … …  
    5959
    6060        if (remaining) {
    61                 if (*remaining<=(ipptr->ip_hl*4U)) {
     61                if (*remaining<(ipptr->ip_hl*4U)) {
    6262                        *remaining = 0;
    6363                        return NULL;
    … …  
    7777{
    7878        void *payload = (char*)ipptr+sizeof(libtrace_ip6_t);
    79         uint8_t nxt = ipptr->nxt;
    80 
    81         if (ipptr == NULL)
    82                 return NULL;
    83        
     79        uint8_t nxt;
     80
     81        assert (ipptr != NULL);
     82        nxt = ipptr->nxt;       
    8483        if (remaining) {
    8584                if (*remaining<sizeof(libtrace_ip6_t)) {

  • lib/protocols_pktmeta.c

    rab25522 raa22b5b  
    2626
    2727        if (remaining) {
    28                 if (*remaining <= sizeof(*sll)) {
     28                if (*remaining < sizeof(*sll)) {
    2929                        *remaining = 0;
    3030                        return NULL;
    … …  
    4545        libtrace_pflog_header_t *pflog = (libtrace_pflog_header_t*)link;
    4646        if (remaining) {
    47                 if (*remaining<=sizeof(*pflog)) {
     47                if (*remaining<sizeof(*pflog)) {
    4848                        *remaining = 0;
    4949                        return NULL;
    … …  
    6262{
    6363        if (remaining) {
    64                 if (*remaining<=144) {
     64                /* Prism header is 144 bytes long */
     65                if (*remaining<144) {
    6566                        *remaining = 0;
    6667                        return NULL;
    … …  
    8182        uint16_t rtaplen = bswap_le_to_host16(rtap->it_len);
    8283        if (remaining) {
    83                 if (*remaining <= rtaplen) {
     84                if (*remaining < rtaplen) {
    8485                        *remaining = 0;
    8586                        return NULL;

  • lib/protocols_transport.c

    r35782f6 raa22b5b  
    3737                       
    3838                default:
     39                        printf("unknown ethertype=%04x\n",ethertype);
    3940                        *proto=0;
    4041                        return NULL;
    … …  
    118119{
    119120        if (remaining) {
    120                 if (*remaining <= sizeof(libtrace_udp_t)) {
     121                if (*remaining < sizeof(libtrace_udp_t)) {
    121122                        *remaining = 0;
    122123                        return NULL;
    … …  
    131132        unsigned int dlen = tcp->doff*4;
    132133        if (remaining) {
    133                 if (*remaining <= dlen) {
     134                if (*remaining < dlen) {
    134135                        *remaining = 0;
    135136                        return NULL;
    … …  
    143144{
    144145        if (remaining) {
    145                 if (*remaining <= sizeof(libtrace_icmp_t)) {
     146                if (*remaining < sizeof(libtrace_icmp_t)) {
    146147                        *remaining = 0;
    147148                        return NULL;
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