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tools lib traceevent: Add support for IP address formats

PATCH In review David Ahern 2 participants 4 messages Dec 17, 2014 – Dec 18, 2014

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#0 lore raw

PATCH 1/1 tools lib traceevent: Add support for IP address formats

Adds helper for 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 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.

Cc Namhyung Kim <[email protected]>
Cc Jiri Olsa <[email protected]>
Cc Steven Rostedt <[email protected]>
---
 tools/lib/traceevent/event-parse.c | 316 +++++++++++++++++++++++++++++++++++++
 1 file changed, 316 insertions(+)
tools/lib/traceevent/event-parse.c +316 -0
index cf3a44bf1ec3..85ab72c650d3 100644
@@ -32,6 +32,7 @@
 #include <stdint.h>
 #include <limits.h>
 
+#include <netinet/ip6.h>
 #include "event-parse.h"
 #include "event-utils.h"
 
@@ -4149,6 +4150,312 @@ 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 (*(ptr + 1) == 'c') {
+		have_c = 1;
+		ptr++;
+		rc++;
+	}
+
+	if (arg->type == PRINT_FUNC) {
+		process_defined_func(s, data, size, event, arg);
+		return rc;
+	}
+
+	if (arg->type != PRINT_FIELD) {
+		trace_seq_printf(s, "ARG TYPE NOT FIELD BUT %d", arg->type);
+		return rc;
+	}
+
+	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 rc;
+		}
+	}
+
+	buf = data + arg->field.field->offset;
+
+	if (arg->field.field->size != 16) {
+		trace_seq_printf(s, "INVALIDIPv6");
+		return rc;
+	}
+
+	if (have_c)
+		print_ip6c_addr(s, buf);
+	else
+		print_ip6_addr(s, i, buf);
+
+	return rc;
+}
+
+static int print_ipsa_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, have_p = 0;
+	unsigned char *buf;
+	struct sockaddr_storage *sa;
+	int rc = 0;
+
+	/* pISpc */
+	if (*(ptr + 1) == 'p') {
+		have_p = 1;
+		ptr++;
+		rc++;
+	}
+	if (*(ptr + 1) == 'c') {
+		have_c = 1;
+		ptr++;
+		rc++;
+	}
+
+	if (arg->type == PRINT_FUNC) {
+		process_defined_func(s, data, size, event, arg);
+		return rc;
+	}
+
+	if (arg->type != PRINT_FIELD) {
+		trace_seq_printf(s, "ARG TYPE NOT FIELD BUT %d", arg->type);
+		return rc;
+	}
+
+	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 rc;
+		}
+	}
+
+	sa = (struct sockaddr_storage *) (data + arg->field.field->offset);
+
+	if (sa->ss_family == AF_INET) {
+		struct sockaddr_in *sa4 = (struct sockaddr_in *) sa;
+
+		print_ip4_addr(s, i, (unsigned char *) &sa4->sin_addr);
+		if (have_p)
+			trace_seq_printf(s, ":%d", ntohs(sa4->sin_port));
+
+
+	} else if (sa->ss_family == AF_INET6) {
+		struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *) sa;
+
+		if (have_p)
+			trace_seq_printf(s, "[");
+
+		buf = (unsigned char *) &sa6->sin6_addr;
+		if (have_c)
+			print_ip6c_addr(s, buf);
+		else
+			print_ip6_addr(s, i, buf);
+
+		if (have_p)
+			trace_seq_printf(s, "]:%d", ntohs(sa6->sin6_port));
+	}
+
+	return rc;
+}
+
+static int print_ip_arg(struct trace_seq *s, const char *ptr,
+			void *data, int size, struct event_format *event,
+			struct print_arg *arg)
+{
+	char i = *(ptr + 1);  /* 'i' or 'I' */
+	char ver;
+	int rc = 0;
+
+	ptr++;
+	rc++;
+
+	ver = *(ptr + 1);
+	ptr++;
+	rc++;
+
+	switch (ver) {
+	case '4':
+		rc += print_ipv4_arg(s, ptr, i, data, size, event, arg);
+		break;
+	case '6':
+		rc += print_ipv6_arg(s, ptr, i, data, size, event, arg);
+		break;
+	case 'S':
+		rc += print_ipsa_arg(s, ptr, i, data, size, event, arg);
+		break;
+	default:
+		return 0;
+	}
+
+	return rc;
+}
+
 static int is_printable_array(char *p, unsigned int len)
 {
 	unsigned int i;
@@ -4337,6 +4644,15 @@ static void pretty_print(struct trace_seq *s, void *data, int size, struct event
 					ptr++;
 					arg = arg->next;
 					break;
+				} else if (*(ptr+1) == 'I' || *(ptr+1) == 'i') {
+					int n;
+
+					n = print_ip_arg(s, ptr, data, size, event, arg);
+					if (n > 0) {
+						ptr += n;
+						arg = arg->next;
+						break;
+					}
 				}
 
 				/* fall through */
Signature · 1 line
1.9.3 (Apple Git-50)
#1 lore raw

Hi David,

Quoted 17 lines · David Ahern

Adds helper for 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 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.

Cc Namhyung Kim <[email protected]>
Cc Jiri Olsa <[email protected]>
Cc Steven Rostedt <[email protected]>

---

[SNIP]

tools/lib/traceevent/event-parse.c static void print_mac_arg(struct trace_seq *s, int mac, void *data, int size, · line 4431

Quoted 5 lines
tools/lib/traceevent/event-parse.c +5 -0
+static int print_ip_arg(struct trace_seq *s, const char *ptr,
+			void *data, int size, struct event_format *event,
+			struct print_arg *arg)
+{
+	char i = *(ptr + 1);  /* 'i' or 'I' */

It'd be better if we do it like below..

	char i = *ptr++;

Why not passing ptr + 1 to print_ip_arg()?

tools/lib/traceevent/event-parse.c static void print_mac_arg(struct trace_seq *s, int mac, void *data, int size, · line 4438

Quoted 7 lines
tools/lib/traceevent/event-parse.c +7 -0
+	char ver;
+	int rc = 0;
+
+	ptr++;
+	rc++;
+
+	ver = *(ptr + 1);

Ditto.

Quoted 24 lines
tools/lib/traceevent/event-parse.c +20 -0
+	ptr++;
+	rc++;
+
+	switch (ver) {
+	case '4':
+		rc += print_ipv4_arg(s, ptr, i, data, size, event, arg);
+		break;
+	case '6':
+		rc += print_ipv6_arg(s, ptr, i, data, size, event, arg);
+		break;
+	case 'S':
+		rc += print_ipsa_arg(s, ptr, i, data, size, event, arg);
+		break;
+	default:
+		return 0;
+	}
+
+	return rc;
+}
+
 static int is_printable_array(char *p, unsigned int len)
 {
 	unsigned int i;

tools/lib/traceevent/event-parse.c static void pretty_print(struct trace_seq *s, void *data, int size, struct event · line 4650

Quoted 7 lines
tools/lib/traceevent/event-parse.c +4 -0
@@ -4337,6 +4644,15 @@ static void pretty_print(struct trace_seq *s, void *data, int size, struct event
 					ptr++;
 					arg = arg->next;
 					break;
+				} else if (*(ptr+1) == 'I' || *(ptr+1) == 'i') {
+					int n;
+
+					n = print_ip_arg(s, ptr, data, size, event, arg);

Here..

Thanks,
Namhyung

Quoted 16 lines
tools/lib/traceevent/event-parse.c +5 -0
+					if (n > 0) {
+						ptr += n;
+						arg = arg->next;
+						break;
+					}
 				}
 
 				/* fall through */
Signature · 7 lines
1.9.3 (Apple Git-50)

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#2 lore raw
Quoted 7 lines · Namhyung Kim

It'd be better if we do it like below..

	char i = *ptr++;

Why not passing ptr + 1 to print_ip_arg()?

That parsing loop is a bit weird - and deep. And I only wanted to consume 'pi' and 'pI' with parse_ip_arg if and only if the next letters are '4', '6' and 'S'.

David

#3 lore raw
Quoted 4 lines · David Ahern
Quoted 3 lines · Namhyung Kim

It'd be better if we do it like below..

Quoted 8 lines
Quoted 4 lines
	char i = *ptr++;

Why not passing ptr + 1 to print_ip_arg()?

That parsing loop is a bit weird - and deep. And I only wanted to consume 'pi' and 'pI' with parse_ip_arg if and only if the next letters are '4', '6' and 'S'.

Yeah, I know - but I still think you can pass ptr + 1 (but not update ptr) since everytime you only access to ptr + 1 unless I missed it. Consuming ptr depends on the return value so it's irrelevant whether you pass ptr or (ptr + 1) IMHO.

Thanks,
Namhyung