From b516c73b71d82f4174c3c9c46c45035ec17da413 Mon Sep 17 00:00:00 2001 From: Erik Auerswald Date: Sun, 1 May 2022 11:50:12 +0200 Subject: [PATCH 3/8] refactor IPv4 address generation and limit CIDR Both functions add_cidr() and add_range() end with the same code. Extract this code into a new function add_addr_range_ipv4() and use it. Additionally, move the check to limit the number of generated addresses to a compile time constant (MAX_GENERATE+1) into the new function. This is a change in "fping -g" behavior, because now both forms of invoking the address generator use the MAX_GENERATE+1 limit. Before, only "fping -g START END" would use this limit, but "fping -g CIDR" would not. Add a test to check if the MAX_GENERATE+1 limit is applied when using "fping -g CIDR". --- ci/test-06-options-f-h.pl | 10 +++++++++- doc/fping.pod | 3 +++ src/fping.c | 15 +++++++-------- 3 files changed, 19 insertions(+), 9 deletions(-) diff --git a/ci/test-06-options-f-h.pl b/ci/test-06-options-f-h.pl index 4f26b9e..2bfde36 100755 --- a/ci/test-06-options-f-h.pl +++ b/ci/test-06-options-f-h.pl @@ -1,6 +1,6 @@ #!/usr/bin/perl -w -use Test::Command tests => 45; +use Test::Command tests => 48; use File::Temp; # -f file read list of targets from a file ( - means stdin) (only if no -g specified) @@ -124,6 +124,14 @@ $cmd->stdout_is_eq(""); $cmd->stderr_is_eq("fping: netmask must be between 1 and 32 (is: 0)\n"); } +# fping -g (cidr - too many addresses) +{ +my $cmd = Test::Command->new(cmd => "fping -g 127.0.0.2/8"); +$cmd->exit_is_num(1); +$cmd->stdout_is_eq(""); +$cmd->stderr_is_eq("fping: -g parameter generates too many addresses\n"); +} + # fping -H { my $cmd = Test::Command->new(cmd => "fping -H 1 127.0.0.1"); diff --git a/doc/fping.pod b/doc/fping.pod index 7702df1..45fc101 100644 --- a/doc/fping.pod +++ b/doc/fping.pod @@ -273,6 +273,9 @@ line arguments, and 4 for a system call failure. =head1 RESTRICTIONS +The number of addresses that can be generated using the C<-g>, C<--generate> +option is limited to a compile-time constant. + If fping was configured with C<--enable-safe-limits>, the following values are not allowed for non-root users: diff --git a/src/fping.c b/src/fping.c index af44a6c..2e69f2b 100644 --- a/src/fping.c +++ b/src/fping.c @@ -388,6 +388,7 @@ struct event *ev_dequeue(struct event_queue *queue); void ev_remove(struct event_queue *queue, struct event *event); void add_cidr(char*); void add_range(char*, char*); +void add_addr_range_ipv4(unsigned long, unsigned long); void print_warning(char* fmt, ...); int addr_cmp(struct sockaddr* a, struct sockaddr* b); void host_add_ping_event(HOST_ENTRY *h, int index, int64_t ev_time); @@ -1227,14 +1228,7 @@ void add_cidr(char* addr) net_addr++; } - /* add all hosts in that network (net_addr and net_last inclusive) */ - for (; net_addr <= net_last; net_addr++) { - struct in_addr in_addr_tmp; - char buffer[20]; - in_addr_tmp.s_addr = htonl(net_addr); - inet_ntop(AF_INET, &in_addr_tmp, buffer, sizeof(buffer)); - add_name(buffer); - } + add_addr_range_ipv4(net_addr, net_last); } void add_range(char* start, char* end) @@ -1278,6 +1272,11 @@ void add_range(char* start, char* end) end_long = ntohl(((struct sockaddr_in*)addr_res->ai_addr)->sin_addr.s_addr); freeaddrinfo(addr_res); + add_addr_range_ipv4(start_long, end_long); +} + +void add_addr_range_ipv4(unsigned long start_long, unsigned long end_long) +{ if (end_long > start_long + MAX_GENERATE) { fprintf(stderr, "%s: -g parameter generates too many addresses\n", prog); exit(1); -- 2.25.1