check_curl: accept non standard compliant status line

If the status line from a server ended with '\n' instead
of '\r\n' (defined by RFC 9112), check_curl failed to parse it
and exited with an alarm.
The RFC recommends to be lenient here and this change follows that
suggestion.

1 files changed, 16 insertions, 2 deletions

diff --git a/plugins/check_curl.d/check_curl_helpers.c b/plugins/check_curl.d/check_curl_helpers.c
index c3c2ba55..d1d282be 100644
--- a/plugins/check_curl.d/check_curl_helpers.c
+++ b/plugins/check_curl.d/check_curl_helpers.c
@@ -4,6 +4,7 @@
 #include <netinet/in.h>
 #include <netdb.h>
 #include <stdlib.h>
+#include <string.h>
 #include "../utils.h"
 #include "check_curl.d/config.h"
 #include "output.h"
@@ -816,7 +817,8 @@ int curlhelp_parse_statusline(const char *buf, curlhelp_statusline *status_line)
                 buf = start;
         }
 
-        char *first_line_end = strstr(buf, "\r\n");
+        size_t length_of_first_line = strcspn(buf, "\r\n");
+        const char *first_line_end = &buf[length_of_first_line];
         if (first_line_end == NULL) {
                 return -1;
         }
@@ -826,6 +828,7 @@ int curlhelp_parse_statusline(const char *buf, curlhelp_statusline *status_line)
         if (status_line->first_line == NULL) {
                 return -1;
         }
+
         memcpy(status_line->first_line, buf, first_line_len);
         status_line->first_line[first_line_len] = '\0';
         char *first_line_buf = strdup(status_line->first_line);
@@ -833,23 +836,34 @@ int curlhelp_parse_statusline(const char *buf, curlhelp_statusline *status_line)
         /* protocol and version: "HTTP/x.x" SP or "HTTP/2" SP */
         char *temp_string = strtok(first_line_buf, "/");
         if (temp_string == NULL) {
+                if (verbose > 1) {
+                        printf("%s: no / found\n", __func__);
+                }
                 free(first_line_buf);
                 return -1;
         }
+
         if (strcmp(temp_string, "HTTP") != 0) {
+                if (verbose > 1) {
+                        printf("%s: string 'HTTP' not found\n", __func__);
+                }
                 free(first_line_buf);
                 return -1;
         }
 
+        // try to find a space in the remaining string?
+        // the space after HTTP/1.1 probably
         temp_string = strtok(NULL, " ");
         if (temp_string == NULL) {
+                if (verbose > 1) {
+                        printf("%s: no space after protocol definition\n", __func__);
+                }
                 free(first_line_buf);
                 return -1;
         }
 
         char *temp_string_2;
         if (strchr(temp_string, '.') != NULL) {
-
                 /* HTTP 1.x case */
                 strtok(temp_string, ".");
                 status_line->http_major = (int)strtol(temp_string, &temp_string_2, 10);