From aaa4ace72ba1d195bbf436134a336816c33f7bd0 Mon Sep 17 00:00:00 2001 From: Jiri Popelka Date: Fri, 4 Jul 2014 15:50:41 +0200 Subject: iptables: add optional [seconds] argument to -w This patch adds an optional numeric argument to -w option (added with 93587a0) so one can specify how long to wait for an exclusive lock. If the value isn't specified it works as before, i.e. program waits indefinitely. If user specifies it, program exits after the given time interval passes. This patch also adds the -w/--wait to nftables compat code, so the parser doesn't complain. [ In the original patch, iptables-compat -w X was not working, I have fixed by adding the dummy code not to break scripts using the new optional argument --pablo ] Signed-off-by: Jiri Popelka Signed-off-by: Pablo Neira Ayuso --- iptables/ip6tables.c | 26 +++++++++++++++++++------- iptables/iptables.8.in | 5 +++-- iptables/iptables.c | 27 +++++++++++++++++++-------- iptables/xshared.c | 8 +++++--- iptables/xshared.h | 2 +- iptables/xtables.c | 13 ++++++++++++- 6 files changed, 59 insertions(+), 22 deletions(-) (limited to 'iptables') diff --git a/iptables/ip6tables.c b/iptables/ip6tables.c index 2ebfd6c0..8db13b45 100644 --- a/iptables/ip6tables.c +++ b/iptables/ip6tables.c @@ -102,7 +102,7 @@ static struct option original_opts[] = { {.name = "numeric", .has_arg = 0, .val = 'n'}, {.name = "out-interface", .has_arg = 1, .val = 'o'}, {.name = "verbose", .has_arg = 0, .val = 'v'}, - {.name = "wait", .has_arg = 0, .val = 'w'}, + {.name = "wait", .has_arg = 2, .val = 'w'}, {.name = "exact", .has_arg = 0, .val = 'x'}, {.name = "version", .has_arg = 0, .val = 'V'}, {.name = "help", .has_arg = 2, .val = 'h'}, @@ -259,7 +259,7 @@ exit_printhelp(const struct xtables_rule_match *matches) " network interface name ([+] for wildcard)\n" " --table -t table table to manipulate (default: `filter')\n" " --verbose -v verbose mode\n" -" --wait -w wait for the xtables lock\n" +" --wait -w [seconds] wait for the xtables lock\n" " --line-numbers print line numbers when listing\n" " --exact -x expand numbers (display exact values)\n" /*"[!] --fragment -f match second or further fragments only\n"*/ @@ -1323,7 +1323,7 @@ int do_command6(int argc, char *argv[], char **table, struct in6_addr *smasks = NULL, *dmasks = NULL; int verbose = 0; - bool wait = false; + int wait = 0; const char *chain = NULL; const char *shostnetworkmask = NULL, *dhostnetworkmask = NULL; const char *policy = NULL, *newname = NULL; @@ -1359,7 +1359,7 @@ int do_command6(int argc, char *argv[], char **table, opts = xt_params->orig_opts; while ((cs.c = getopt_long(argc, argv, - "-:A:C:D:R:I:L::S::M:F::Z::N:X::E:P:Vh::o:p:s:d:j:i:bvwnt:m:xc:g:46", + "-:A:C:D:R:I:L::S::M:F::Z::N:X::E:P:Vh::o:p:s:d:j:i:bvw::nt:m:xc:g:46", opts, NULL)) != -1) { switch (cs.c) { /* @@ -1603,7 +1603,16 @@ int do_command6(int argc, char *argv[], char **table, "You cannot use `-w' from " "ip6tables-restore"); } - wait = true; + wait = -1; + if (optarg) { + if (sscanf(optarg, "%i", &wait) != 1) + xtables_error(PARAMETER_PROBLEM, + "wait seconds not numeric"); + } else if (optind < argc && argv[optind][0] != '-' + && argv[optind][0] != '!') + if (sscanf(argv[optind++], "%i", &wait) != 1) + xtables_error(PARAMETER_PROBLEM, + "wait seconds not numeric"); break; case 'm': @@ -1754,8 +1763,11 @@ int do_command6(int argc, char *argv[], char **table, /* Attempt to acquire the xtables lock */ if (!restore && !xtables_lock(wait)) { - fprintf(stderr, "Another app is currently holding the xtables lock. " - "Perhaps you want to use the -w option?\n"); + fprintf(stderr, "Another app is currently holding the xtables lock. "); + if (wait == 0) + fprintf(stderr, "Perhaps you want to use the -w option?\n"); + else + fprintf(stderr, "Stopped waiting after %ds.\n", wait); xtables_free_opts(1); exit(RESOURCE_PROBLEM); } diff --git a/iptables/iptables.8.in b/iptables/iptables.8.in index 8ef222e5..ceba5dc2 100644 --- a/iptables/iptables.8.in +++ b/iptables/iptables.8.in @@ -359,12 +359,13 @@ For appending, insertion, deletion and replacement, this causes detailed information on the rule or rules to be printed. \fB\-v\fP may be specified multiple times to possibly emit more detailed debug statements. .TP -\fB\-w\fP, \fB\-\-wait\fP +\fB\-w\fP, \fB\-\-wait\fP [\fIseconds\fP] Wait for the xtables lock. To prevent multiple instances of the program from running concurrently, an attempt will be made to obtain an exclusive lock at launch. By default, the program will exit if the lock cannot be obtained. This option will -make the program wait until the exclusive lock can be obtained. +make the program wait (indefinitely or for optional \fIseconds\fP) until +the exclusive lock can be obtained. .TP \fB\-n\fP, \fB\-\-numeric\fP Numeric output. diff --git a/iptables/iptables.c b/iptables/iptables.c index 471bff06..88953c47 100644 --- a/iptables/iptables.c +++ b/iptables/iptables.c @@ -99,7 +99,7 @@ static struct option original_opts[] = { {.name = "numeric", .has_arg = 0, .val = 'n'}, {.name = "out-interface", .has_arg = 1, .val = 'o'}, {.name = "verbose", .has_arg = 0, .val = 'v'}, - {.name = "wait", .has_arg = 0, .val = 'w'}, + {.name = "wait", .has_arg = 2, .val = 'w'}, {.name = "exact", .has_arg = 0, .val = 'x'}, {.name = "fragments", .has_arg = 0, .val = 'f'}, {.name = "version", .has_arg = 0, .val = 'V'}, @@ -253,7 +253,7 @@ exit_printhelp(const struct xtables_rule_match *matches) " network interface name ([+] for wildcard)\n" " --table -t table table to manipulate (default: `filter')\n" " --verbose -v verbose mode\n" -" --wait -w wait for the xtables lock\n" +" --wait -w [seconds] wait for the xtables lock\n" " --line-numbers print line numbers when listing\n" " --exact -x expand numbers (display exact values)\n" "[!] --fragment -f match second or further fragments only\n" @@ -1319,7 +1319,7 @@ int do_command4(int argc, char *argv[], char **table, struct in_addr *daddrs = NULL, *dmasks = NULL; int verbose = 0; - bool wait = false; + int wait = 0; const char *chain = NULL; const char *shostnetworkmask = NULL, *dhostnetworkmask = NULL; const char *policy = NULL, *newname = NULL; @@ -1352,10 +1352,9 @@ int do_command4(int argc, char *argv[], char **table, /* Suppress error messages: we may add new options if we demand-load a protocol. */ opterr = 0; - opts = xt_params->orig_opts; while ((cs.c = getopt_long(argc, argv, - "-:A:C:D:R:I:L::S::M:F::Z::N:X::E:P:Vh::o:p:s:d:j:i:fbvwnt:m:xc:g:46", + "-:A:C:D:R:I:L::S::M:F::Z::N:X::E:P:Vh::o:p:s:d:j:i:fbvw::nt:m:xc:g:46", opts, NULL)) != -1) { switch (cs.c) { /* @@ -1597,7 +1596,16 @@ int do_command4(int argc, char *argv[], char **table, "You cannot use `-w' from " "iptables-restore"); } - wait = true; + wait = -1; + if (optarg) { + if (sscanf(optarg, "%i", &wait) != 1) + xtables_error(PARAMETER_PROBLEM, + "wait seconds not numeric"); + } else if (optind < argc && argv[optind][0] != '-' + && argv[optind][0] != '!') + if (sscanf(argv[optind++], "%i", &wait) != 1) + xtables_error(PARAMETER_PROBLEM, + "wait seconds not numeric"); break; case 'm': @@ -1751,8 +1759,11 @@ int do_command4(int argc, char *argv[], char **table, /* Attempt to acquire the xtables lock */ if (!restore && !xtables_lock(wait)) { - fprintf(stderr, "Another app is currently holding the xtables lock. " - "Perhaps you want to use the -w option?\n"); + fprintf(stderr, "Another app is currently holding the xtables lock. "); + if (wait == 0) + fprintf(stderr, "Perhaps you want to use the -w option?\n"); + else + fprintf(stderr, "Stopped waiting after %ds.\n", wait); xtables_free_opts(1); exit(RESOURCE_PROBLEM); } diff --git a/iptables/xshared.c b/iptables/xshared.c index 6c9992ed..b18022ee 100644 --- a/iptables/xshared.c +++ b/iptables/xshared.c @@ -243,10 +243,11 @@ void xs_init_match(struct xtables_match *match) match->init(match->m); } -bool xtables_lock(bool wait) +bool xtables_lock(int wait) { int i = 0, ret, xt_socket; struct sockaddr_un xt_addr; + int waited = 0; memset(&xt_addr, 0, sizeof(xt_addr)); xt_addr.sun_family = AF_UNIX; @@ -261,11 +262,12 @@ bool xtables_lock(bool wait) offsetof(struct sockaddr_un, sun_path)+XT_SOCKET_LEN); if (ret == 0) return true; - else if (wait == false) + else if (wait >= 0 && waited >= wait) return false; if (++i % 2 == 0) fprintf(stderr, "Another app is currently holding the xtables lock; " - "waiting for it to exit...\n"); + "waiting (%ds) for it to exit...\n", waited); + waited++; sleep(1); } } diff --git a/iptables/xshared.h b/iptables/xshared.h index 27c5b786..40dd9154 100644 --- a/iptables/xshared.h +++ b/iptables/xshared.h @@ -85,7 +85,7 @@ extern struct xtables_match *load_proto(struct iptables_command_state *); extern int subcmd_main(int, char **, const struct subcommand *); extern void xs_init_target(struct xtables_target *); extern void xs_init_match(struct xtables_match *); -extern bool xtables_lock(bool wait); +extern bool xtables_lock(int wait); extern const struct xtables_afinfo *afinfo; diff --git a/iptables/xtables.c b/iptables/xtables.c index 45a5ac63..d661dd16 100644 --- a/iptables/xtables.c +++ b/iptables/xtables.c @@ -85,6 +85,7 @@ static struct option original_opts[] = { {.name = "numeric", .has_arg = 0, .val = 'n'}, {.name = "out-interface", .has_arg = 1, .val = 'o'}, {.name = "verbose", .has_arg = 0, .val = 'v'}, + {.name = "wait", .has_arg = 2, .val = 'w'}, {.name = "exact", .has_arg = 0, .val = 'x'}, {.name = "fragments", .has_arg = 0, .val = 'f'}, {.name = "version", .has_arg = 0, .val = 'V'}, @@ -683,6 +684,7 @@ int do_commandx(struct nft_handle *h, int argc, char *argv[], char **table, { struct iptables_command_state cs; int verbose = 0; + int wait = 0; const char *chain = NULL; const char *policy = NULL, *newname = NULL; unsigned int rulenum = 0, command = 0; @@ -722,7 +724,7 @@ int do_commandx(struct nft_handle *h, int argc, char *argv[], char **table, opts = xt_params->orig_opts; while ((cs.c = getopt_long(argc, argv, - "-:A:C:D:R:I:L::S::M:F::Z::N:X::E:P:Vh::o:p:s:d:j:i:fbvnt:m:xc:g:46", + "-:A:C:D:R:I:L::S::M:F::Z::N:X::E:P:Vh::o:p:s:d:j:i:fbvw::nt:m:xc:g:46", opts, NULL)) != -1) { switch (cs.c) { /* @@ -1007,6 +1009,15 @@ int do_commandx(struct nft_handle *h, int argc, char *argv[], char **table, "You cannot use `-w' from " "iptables-restore"); } + if (optarg) { + if (sscanf(optarg, "%i", &wait) != 1) + xtables_error(PARAMETER_PROBLEM, + "wait seconds not numeric"); + } else if (optind < argc && argv[optind][0] != '-' + && argv[optind][0] != '!') + if (sscanf(argv[optind++], "%i", &wait) != 1) + xtables_error(PARAMETER_PROBLEM, + "wait seconds not numeric"); break; case '0': -- cgit v1.2.3