[PATCH iproute2 1/2] utils: add print_escape_buf to format and print arbitrary bytes

[PATCH iproute2 1/2] utils: add print_escape_buf to format and print arbitrary bytes

[Ivan Delalande]

Keep it as simple as possible for now: just escape anything that is not
isprint-able, is among the "escape" parameter or '\' as an octal escape
sequence. This should be pretty easy to extend if any other user needs
something more complex in the future.

Signed-off-by: Ivan Delalande <colona@arista.com>
---
 include/utils.h |  2 ++
 lib/utils.c     | 15 +++++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/include/utils.h b/include/utils.h
index 76addb32..3d91c50d 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -195,6 +195,8 @@ static inline void __jiffies_to_tv(struct timeval *tv, unsigned long jiffies)
 	tv->tv_usec = tvusec - 1000000 * tv->tv_sec;
 }
 
+void print_escape_buf(const __u8 *buf, size_t len, const char *escape);
+
 int print_timestamp(FILE *fp);
 void print_nlmsg_timestamp(FILE *fp, const struct nlmsghdr *n);
 
diff --git a/lib/utils.c b/lib/utils.c
index 0cf99619..a494190e 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -31,6 +31,7 @@
 #include <time.h>
 #include <sys/time.h>
 #include <errno.h>
+#include <ctype.h>
 
 #include "rt_names.h"
 #include "utils.h"
@@ -1047,6 +1048,20 @@ int addr64_n2a(__u64 addr, char *buff, size_t len)
 	return written;
 }
 
+/* Print buffer and escape bytes that are !isprint or among 'escape' */
+void print_escape_buf(const __u8 *buf, size_t len, const char *escape)
+{
+	size_t i;
+
+	for (i = 0; i < len; ++i) {
+		if (isprint(buf[i]) && buf[i] != '\\' &&
+		    !strchr(escape, buf[i]))
+			printf("%c", buf[i]);
+		else
+			printf("\\%03o", buf[i]);
+	}
+}
+
 int print_timestamp(FILE *fp)
 {
 	struct timeval tv;
-- 
2.14.2

[PATCH iproute2 2/2] ss: print MD5 signature keys configured on TCP sockets

[Ivan Delalande]

These keys are reported by kernel 4.14 and later under the
INET_DIAG_MD5SIG attribute, when INET_DIAG_INFO is requested (ss -i)
and we have CAP_NET_ADMIN. The additional output looks like:

	md5keys:fe80::/64=signing_key,10.1.2.0/24=foobar,::1/128=Test

Signed-off-by: Ivan Delalande <colona@arista.com>
---
 misc/ss.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/misc/ss.c b/misc/ss.c
index dd8dfaa4..09bff8a7 100644
--- a/misc/ss.c
+++ b/misc/ss.c
@@ -2153,6 +2153,16 @@ static void print_skmeminfo(struct rtattr *tb[], int attrtype)
 	printf(")");
 }
 
+static void print_md5sig(struct tcp_diag_md5sig *sig)
+{
+	printf("%s/%d=",
+	       format_host(sig->tcpm_family,
+			   sig->tcpm_family == AF_INET6 ? 16 : 4,
+			   &sig->tcpm_addr),
+	       sig->tcpm_prefixlen);
+	print_escape_buf(sig->tcpm_key, sig->tcpm_keylen, " ,");
+}
+
 #define TCPI_HAS_OPT(info, opt) !!(info->tcpi_options & (opt))
 
 static void tcp_show_info(const struct nlmsghdr *nlh, struct inet_diag_msg *r,
@@ -2289,6 +2299,17 @@ static void tcp_show_info(const struct nlmsghdr *nlh, struct inet_diag_msg *r,
 		free(s.dctcp);
 		free(s.bbr_info);
 	}
+	if (tb[INET_DIAG_MD5SIG]) {
+		struct tcp_diag_md5sig *sig = RTA_DATA(tb[INET_DIAG_MD5SIG]);
+		int len = RTA_PAYLOAD(tb[INET_DIAG_MD5SIG]);
+
+		printf(" md5keys:");
+		print_md5sig(sig++);
+		for (len -= sizeof(*sig); len > 0; len -= sizeof(*sig)) {
+			printf(",");
+			print_md5sig(sig++);
+		}
+	}
 }
 
 static const char *format_host_sa(struct sockaddr_storage *sa)
-- 
2.14.2

Re: [PATCH iproute2 2/2] ss: print MD5 signature keys configured on TCP sockets

[Stephen Hemminger]

On Fri,  6 Oct 2017 16:48:20 -0700
Ivan Delalande <colona@arista.com> wrote:

> These keys are reported by kernel 4.14 and later under the
> INET_DIAG_MD5SIG attribute, when INET_DIAG_INFO is requested (ss -i)
> and we have CAP_NET_ADMIN. The additional output looks like:
> 
> 	md5keys:fe80::/64=signing_key,10.1.2.0/24=foobar,::1/128=Test
> 
> Signed-off-by: Ivan Delalande <colona@arista.com>

Sure makes sense applied.