tools lib traceevent: Add support for IP address formats

Add helpers for the following kernel formats:
  %pi4 print an IPv4 address with leading zeros
  %pI4 print an IPv4 address without leading zeros
  %pi6 print an IPv6 address without colons
  %pI6 print an IPv6 address with colons
  %pI6c print an IPv6 address in compressed form with colons
  %pISpc print an IP address from a sockaddr

Allows these formats to be used in tracepoints.

Quite a bit of this is adapted from code in lib/vsprintf.c.

v4:
- fixed pI6c description in git commit message per Valdis' comment

v3:
- use of 'c' and 'p' requires 'I'

v2:
- pass ptr+1 to print_ip_arg per Namhyung's comments
- added field length checks to sockaddr function

Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1418955071-36241-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 328 insertions, 0 deletions

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index cf3a44bf1ec3..afe20ed9fac8 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -32,6 +32,7 @@
 #include <stdint.h>
 #include <limits.h>
 
+#include <netinet/ip6.h>
 #include "event-parse.h"
 #include "event-utils.h"
 
@@ -4149,6 +4150,324 @@ static void print_mac_arg(struct trace_seq *s, int mac, void *data, int size,
         trace_seq_printf(s, fmt, buf[0], buf[1], buf[2], buf[3], buf[4], buf[5]);
 }
 
+static void print_ip4_addr(struct trace_seq *s, char i, unsigned char *buf)
+{
+        const char *fmt;
+
+        if (i == 'i')
+                fmt = "%03d.%03d.%03d.%03d";
+        else
+                fmt = "%d.%d.%d.%d";
+
+        trace_seq_printf(s, fmt, buf[0], buf[1], buf[2], buf[3]);
+}
+
+static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
+{
+        return ((unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
+                (unsigned long)(a->s6_addr32[2] ^ htonl(0x0000ffff))) == 0UL;
+}
+
+static inline bool ipv6_addr_is_isatap(const struct in6_addr *addr)
+{
+        return (addr->s6_addr32[2] | htonl(0x02000000)) == htonl(0x02005EFE);
+}
+
+static void print_ip6c_addr(struct trace_seq *s, unsigned char *addr)
+{
+        int i, j, range;
+        unsigned char zerolength[8];
+        int longest = 1;
+        int colonpos = -1;
+        uint16_t word;
+        uint8_t hi, lo;
+        bool needcolon = false;
+        bool useIPv4;
+        struct in6_addr in6;
+
+        memcpy(&in6, addr, sizeof(struct in6_addr));
+
+        useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
+
+        memset(zerolength, 0, sizeof(zerolength));
+
+        if (useIPv4)
+                range = 6;
+        else
+                range = 8;
+
+        /* find position of longest 0 run */
+        for (i = 0; i < range; i++) {
+                for (j = i; j < range; j++) {
+                        if (in6.s6_addr16[j] != 0)
+                                break;
+                        zerolength[i]++;
+                }
+        }
+        for (i = 0; i < range; i++) {
+                if (zerolength[i] > longest) {
+                        longest = zerolength[i];
+                        colonpos = i;
+                }
+        }
+        if (longest == 1)               /* don't compress a single 0 */
+                colonpos = -1;
+
+        /* emit address */
+        for (i = 0; i < range; i++) {
+                if (i == colonpos) {
+                        if (needcolon || i == 0)
+                                trace_seq_printf(s, ":");
+                        trace_seq_printf(s, ":");
+                        needcolon = false;
+                        i += longest - 1;
+                        continue;
+                }
+                if (needcolon) {
+                        trace_seq_printf(s, ":");
+                        needcolon = false;
+                }
+                /* hex u16 without leading 0s */
+                word = ntohs(in6.s6_addr16[i]);
+                hi = word >> 8;
+                lo = word & 0xff;
+                if (hi)
+                        trace_seq_printf(s, "%x%02x", hi, lo);
+                else
+                        trace_seq_printf(s, "%x", lo);
+
+                needcolon = true;
+        }
+
+        if (useIPv4) {
+                if (needcolon)
+                        trace_seq_printf(s, ":");
+                print_ip4_addr(s, 'I', &in6.s6_addr[12]);
+        }
+
+        return;
+}
+
+static void print_ip6_addr(struct trace_seq *s, char i, unsigned char *buf)
+{
+        int j;
+
+        for (j = 0; j < 16; j += 2) {
+                trace_seq_printf(s, "%02x%02x", buf[j], buf[j+1]);
+                if (i == 'I' && j < 14)
+                        trace_seq_printf(s, ":");
+        }
+}
+
+/*
+ * %pi4   print an IPv4 address with leading zeros
+ * %pI4   print an IPv4 address without leading zeros
+ * %pi6   print an IPv6 address without colons
+ * %pI6   print an IPv6 address with colons
+ * %pI6c  print an IPv6 address in compressed form with colons
+ * %pISpc print an IP address based on sockaddr; p adds port.
+ */
+static int print_ipv4_arg(struct trace_seq *s, const char *ptr, char i,
+                          void *data, int size, struct event_format *event,
+                          struct print_arg *arg)
+{
+        unsigned char *buf;
+
+        if (arg->type == PRINT_FUNC) {
+                process_defined_func(s, data, size, event, arg);
+                return 0;
+        }
+
+        if (arg->type != PRINT_FIELD) {
+                trace_seq_printf(s, "ARG TYPE NOT FIELD BUT %d", arg->type);
+                return 0;
+        }
+
+        if (!arg->field.field) {
+                arg->field.field =
+                        pevent_find_any_field(event, arg->field.name);
+                if (!arg->field.field) {
+                        do_warning("%s: field %s not found",
+                                   __func__, arg->field.name);
+                        return 0;
+                }
+        }
+
+        buf = data + arg->field.field->offset;
+
+        if (arg->field.field->size != 4) {
+                trace_seq_printf(s, "INVALIDIPv4");
+                return 0;
+        }
+        print_ip4_addr(s, i, buf);
+
+        return 0;
+}
+
+static int print_ipv6_arg(struct trace_seq *s, const char *ptr, char i,
+                          void *data, int size, struct event_format *event,
+                          struct print_arg *arg)
+{
+        char have_c = 0;
+        unsigned char *buf;
+        int rc = 0;
+
+        /* pI6c */
+        if (i == 'I' && *ptr == 'c') {
+                have_c = 1;
+                ptr++;
+                rc++;
+        }
+
+        if (arg->type == PRINT_FUNC) {
+                process_defined_f