From Colin O'Flynn:
[obnox/wireshark/wip.git] / pcapio.c
index b11dad00ca641a30831318bdfca95e8fa022c07c..6029532d72a23d924eca492f8877a0ed749a4897 100644 (file)
--- a/pcapio.c
+++ b/pcapio.c
@@ -66,7 +66,7 @@
    is a byte-swapped version of that.
 
    PCAP_NSEC_MAGIC is for Ulf Lamping's modified "libpcap" format,
-   which uses the same common file format as PCAP_MAGIC, but the 
+   which uses the same common file format as PCAP_MAGIC, but the
    timestamps are saved in nanosecond resolution instead of microseconds.
    PCAP_SWAPPED_NSEC_MAGIC is a byte-swapped version of that. */
 #define        PCAP_MAGIC                      0xa1b2c3d4
@@ -182,7 +182,6 @@ struct option {
                        } else {                                                           \
                                *error_pointer = 0;                                        \
                        }                                                                  \
-                       fclose(file_pointer);                                              \
                        return FALSE;                                                      \
                }                                                                          \
                written_length += (long)nwritten;                                          \
@@ -269,7 +268,7 @@ libpcap_write_packet(FILE *fp, const struct pcap_pkthdr *phdr, const u_char *pd,
 
 gboolean
 libpcap_write_session_header_block(FILE *fp,
-                                   char *appname,
+                                   const char *appname,
                                    long *bytes_written,
                                    int *err)
 {
@@ -277,11 +276,13 @@ libpcap_write_session_header_block(FILE *fp,
        struct option option;
        guint32 block_total_length;
        const guint32 padding = 0;
-       
+
        block_total_length = sizeof(struct shb) +
-                            sizeof(struct option) + (guint16)(ADD_PADDING(strlen(appname) + 1)) +
-                            sizeof(struct option) +
                             sizeof(guint32);
+       if ((strlen(appname) > 0) && (strlen(appname) < G_MAXUINT16)) {
+               block_total_length += 2 * sizeof(struct option) +
+                                     (guint16)(ADD_PADDING(strlen(appname) + 1));
+       }
        /* write shb header */
        shb.block_type = SECTION_HEADER_BLOCK_TYPE;
        shb.block_total_length = block_total_length;
@@ -290,18 +291,21 @@ libpcap_write_session_header_block(FILE *fp,
        shb.minor_version = PCAPNG_MINOR_VERSION;
        shb.section_length = -1;
        WRITE_DATA(fp, &shb, sizeof(struct shb), *bytes_written, err);
-       /* write shb_userappl options */
-       option.type = SHB_USERAPPL;
-       option.value_length = (guint16)(strlen(appname) + 1);
-       WRITE_DATA(fp, &option, sizeof(struct option), *bytes_written, err);
-       WRITE_DATA(fp, appname, strlen(appname) + 1, *bytes_written, err);
-       if ((strlen(appname) + 1) % 4) {
-               WRITE_DATA(fp, &padding, 4 - (strlen(appname) + 1) % 4, *bytes_written, err);
+
+       if ((strlen(appname) > 0) && (strlen(appname) < G_MAXUINT16)) {
+               /* write shb_userappl options */
+               option.type = SHB_USERAPPL;
+               option.value_length = (guint16)(strlen(appname) + 1);
+               WRITE_DATA(fp, &option, sizeof(struct option), *bytes_written, err);
+               WRITE_DATA(fp, appname, strlen(appname) + 1, *bytes_written, err);
+               if ((strlen(appname) + 1) % 4) {
+                       WRITE_DATA(fp, &padding, 4 - (strlen(appname) + 1) % 4, *bytes_written, err);
+               }
+               /* write last option */
+               option.type = OPT_ENDOFOPT;
+               option.value_length = 0;
+               WRITE_DATA(fp, &option, sizeof(struct option), *bytes_written, err);
        }
-       /* write last option */
-       option.type = OPT_ENDOFOPT;
-       option.value_length = 0;
-       WRITE_DATA(fp, &option, sizeof(struct option), *bytes_written, err);
        /* write the trailing block total length */
        WRITE_DATA(fp, &block_total_length, sizeof(guint32), *bytes_written, err);
        return TRUE;
@@ -309,8 +313,8 @@ libpcap_write_session_header_block(FILE *fp,
 
 gboolean
 libpcap_write_interface_description_block(FILE *fp,
-                                          char *name,
-                                          char *filter,
+                                          const char *name,
+                                          const char *filter,
                                           int link_type,
                                           int snap_len,
                                           long *bytes_written,
@@ -322,23 +326,27 @@ libpcap_write_interface_description_block(FILE *fp,
        const guint32 padding = 0;
 
        block_total_length = sizeof(struct idb) + sizeof(guint32);
-       if (strlen(name) > 0) {
-               block_total_length += sizeof(struct option) + ADD_PADDING(strlen(name) + 1);
+       if ((strlen(name) > 0) && (strlen(name) < G_MAXUINT16)) {
+               block_total_length += sizeof(struct option) +
+                                     (guint16)(ADD_PADDING(strlen(name) + 1));
        }
-       if (strlen(filter) > 0) {
-               block_total_length += sizeof(struct option) + ADD_PADDING(strlen(filter) + 1);
+       if ((strlen(filter) > 0) && (strlen(filter) < G_MAXUINT16)) {
+               block_total_length += sizeof(struct option) +
+                                     (guint16)(ADD_PADDING(strlen(filter) + 1));
        }
-       if ((strlen(name) > 0) || (strlen(filter) > 0)) {
+       if (((strlen(name) > 0) && (strlen(name) < G_MAXUINT16)) ||
+           ((strlen(filter) > 0) && (strlen(filter) < G_MAXUINT16))) {
                block_total_length += sizeof(struct option);
        }
+       /* write block header */
        idb.block_type = INTERFACE_DESCRIPTION_BLOCK_TYPE;
        idb.block_total_length = block_total_length;
        idb.link_type = link_type;
        idb.reserved = 0;
        idb.snap_len = snap_len;
        WRITE_DATA(fp, &idb, sizeof(struct idb), *bytes_written, err);
-       /* write the options */
-       if (strlen(name) > 0) {
+       /* write interface name string if applicable */
+       if ((strlen(name) > 0) && (strlen(name) < G_MAXUINT16)) {
                option.type = IDB_NAME;
                option.value_length = (guint16)(strlen(name) + 1);
                WRITE_DATA(fp, &option, sizeof(struct option), *bytes_written, err);
@@ -347,7 +355,8 @@ libpcap_write_interface_description_block(FILE *fp,
                        WRITE_DATA(fp, &padding, 4 - (strlen(name) + 1) % 4 , *bytes_written, err);
                }
        }
-       if (strlen(filter) > 0) {
+       /* write filter string if applicable */
+       if ((strlen(filter) > 0) && (strlen(filter) < G_MAXUINT16)) {
                option.type = IDB_FILTER;
                option.value_length = (guint16)(strlen(filter) + 1);
                WRITE_DATA(fp, &option, sizeof(struct option), *bytes_written, err);
@@ -356,7 +365,9 @@ libpcap_write_interface_description_block(FILE *fp,
                        WRITE_DATA(fp, &padding, 4 - (strlen(filter) + 1) % 4 , *bytes_written, err);
                }
        }
-       if ((strlen(name) > 0) || (strlen(filter) > 0)) {
+       /* write endofopt option if there were any options */
+       if (((strlen(name) > 0) && (strlen(name) < G_MAXUINT16)) ||
+           ((strlen(filter) > 0) && (strlen(filter) < G_MAXUINT16))) {
                option.type = OPT_ENDOFOPT;
                option.value_length = 0;
                WRITE_DATA(fp, &option, sizeof(struct option), *bytes_written, err);
@@ -421,7 +432,7 @@ libpcap_write_interface_statistics_block(FILE *fp,
        guint64 timestamp;
        guint64 counter;
        gboolean stats_retrieved;
-       
+
 #ifdef _WIN32
        /*
         * Current time, represented as 100-nanosecond intervals since
@@ -431,8 +442,8 @@ libpcap_write_interface_statistics_block(FILE *fp,
         * to guint32 so that the sign bit doesn't get treated specially.
         */
        GetSystemTimeAsFileTime(&now);
-       timestamp = ((guint64)(guint32)now.dwHighDateTime) << 32 +
-           (guint32)now.dwLowDateTime;
+       timestamp = (((guint64)(guint32)now.dwHighDateTime) << 32) +
+                   (guint32)now.dwLowDateTime;
 
        /*
         * Convert to same thing but as 1-microsecond, i.e. 1000-nanosecond,
@@ -448,7 +459,7 @@ libpcap_write_interface_statistics_block(FILE *fp,
 #else
        /*
         * Current time, represented as seconds and microseconds since
-        * January 1, 1601, 00:00:00 UTC.
+        * January 1, 1970, 00:00:00 UTC.
         */
        gettimeofday(&now, NULL);
 
@@ -494,7 +505,7 @@ libpcap_write_interface_statistics_block(FILE *fp,
                WRITE_DATA(fp, &option, sizeof(struct option), *bytes_written, err);
        }
        WRITE_DATA(fp, &block_total_length, sizeof(guint32), *bytes_written, err);
-       
+
        return TRUE;
 }