check_dmi_data_match fails because of whitespaces

[rpabel]

The autogenerated nhc.conf on some of our nodes contains spaces in check_dmi_data_match tests like this:

check_dmi_data_match -h 0x0400 -t 4 "Processor Information: Version: Intel(R) Xeon(R) CPU           X5550  @ 2.67GHz"

The string is later read in and passed around and when it is fed to eval, the whitespaces are collapsed:

1510827263] - DEBUG:  Glob match check:  Processor Information: Version: Intel(R) Xeon(R) CPU           X5550  @ 2.67GHz does not match Processor Information: Version: Intel(R) Xeon(R) CPU X5550 @ 2.67GHz

The easiest workaround I found is escaping all whitespaces twice:

check_dmi_data_match -h 0x0401 -t 4 "Processor\\ Information:\\ Version:\\ Intel(R)\\ Xeon(R)\\ CPU\\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ X5550\\ \\ @\\ 2.67GHz"

Now the tests run just fine:

Running check:  "check_dmi_data_match -h 0x0400 -t 4 "Processor\ Information:\ Version:\ Intel(R)\ Xeon(R)\ CPU\ \ \ \ \ \ \ \ \ \ \ X5550\ \ @\ 2.67GHz"

I've adapted nhc-genconf to change the output if two consecutive whitespaces are found:

diff -ruN nhc.orig/nhc-genconf nhc/nhc-genconf
--- nhc.orig/nhc-genconf        2017-11-16 11:38:10.872479034 +0100
+++ nhc/nhc-genconf     2017-11-16 11:37:43.041458469 +0100
@@ -248,7 +248,12 @@
             IFS=$' \t\n'
             for ((i=0; i<${#LINES[*]}; i++)); do
                 if mcheck "${LINES[$i]}" "$DMI_MATCH"; then
-                    echo "# $HOSTNAME || check_dmi_data_match -h $HANDLE ${DMI_TYPE_IDS[$HANDLE]:+-t ${DMI_TYPE_IDS[$HANDLE]}} \"${LINES[i]}\""
+                    if [[ "${LINES[$i]}" == *"  "* ]]; then
+                        ESCAPED=$(echo "${LINES[i]}" | sed 's/\([ ]\)/\\\\\1/g')
+                        echo "# $HOSTNAME || check_dmi_data_match -h $HANDLE ${DMI_TYPE_IDS[$HANDLE]:+-t ${DMI_TYPE_IDS[$HANDLE]}} \"${ESCAPED}\""
+                    else
+                        echo "# $HOSTNAME || check_dmi_data_match -h $HANDLE ${DMI_TYPE_IDS[$HANDLE]:+-t ${DMI_TYPE_IDS[$HANDLE]}} \"${LINES[i]}\""
+                    fi
                 fi
             done
         done

But maybe this should be fixed at the point where the whitespaces are collapsed due to missing quotation marks?

Roland

[mej]

I'm trying to evaluate if this is the best solution or if there's some quoting missing somewhere that needs to be fixed.

[rpabel]

I've finally come back to look into this: The problem seems to be in the main nhc script, lines 629 and 633:

629: eval $CHECK
633: eval $CHECK &

If CHECK contains multiple consecutive whitespaces, they are removed. Inserting quotes preserves them:

eval "$CHECK"

The effect can be seen quickly like this:

[root@cheops10101 nhc]# A='echo "A   B     C"'
[root@cheops10101 nhc]# eval $A
A B C
[root@cheops10101 nhc]# eval "$A"
A   B     C
[root@cheops10101 nhc]#