From 6f1713f216fef686a68db5ee02232bc67e525c7d Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Mon, 25 Feb 2008 23:23:58 +0000 Subject: *: intrduce and use safe_gethostname. By Tito safe_gethostname - 48 +48 glob3 35 37 +2 timestamp_and_log 314 315 +1 udhcp_send_kernel_packet 234 231 -3 scan_tree 275 271 -4 passwd_main 1074 1070 -4 print_login_prompt 68 58 -10 obscure 392 377 -15 syslogd_main 882 866 -16 print_login_issue 516 478 -38 hostname_main 278 223 -55 parse_and_put_prompt 825 756 -69 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 2/9 up/down: 51/-214) Total: -163 bytes text data bss dec hex filename 798791 728 7484 807003 c505b busybox_old 798631 728 7484 806843 c4fbb busybox_unstripped --- include/libbb.h | 2 ++ libbb/Kbuild | 1 + libbb/lineedit.c | 6 +----- libbb/login.c | 14 +++++--------- libbb/obscure.c | 13 ++++++------- miscutils/devfsd.c | 10 +++------- networking/hostname.c | 18 +++++++++--------- sysklogd/syslogd.c | 13 +++++-------- 8 files changed, 32 insertions(+), 45 deletions(-) diff --git a/include/libbb.h b/include/libbb.h index 1ea2e35be..978cd2d87 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -550,6 +550,8 @@ extern FILE *fopen_or_warn_stdin(const char *filename); * If this is a problem, use bare poll and open-code EINTR/ENOMEM handling */ int safe_poll(struct pollfd *ufds, nfds_t nfds, int timeout_ms); +char *safe_gethostname(void); + /* Convert each alpha char in str to lower-case */ char* str_tolower(char *str); diff --git a/libbb/Kbuild b/libbb/Kbuild index 515368de7..aab016e85 100644 --- a/libbb/Kbuild +++ b/libbb/Kbuild @@ -73,6 +73,7 @@ lib-y += recursive_action.o lib-y += remove_file.o lib-y += restricted_shell.o lib-y += run_shell.o +lib-y += safe_gethostname.o lib-y += safe_poll.o lib-y += safe_strncpy.o lib-y += safe_write.o diff --git a/libbb/lineedit.c b/libbb/lineedit.c index 9aab63702..c6aa45c93 100644 --- a/libbb/lineedit.c +++ b/libbb/lineedit.c @@ -1203,11 +1203,7 @@ static void parse_and_put_prompt(const char *prmt_ptr) break; #endif case 'h': - pbuf = free_me = xzalloc(256); - if (gethostname(pbuf, 255) < 0) { - pbuf[0] = '?'; - pbuf[1] = '\0'; - } + pbuf = free_me = safe_gethostname(); *strchrnul(pbuf, '.') = '\0'; break; case '$': diff --git a/libbb/login.c b/libbb/login.c index d1f5d6498..a711a5437 100644 --- a/libbb/login.c +++ b/libbb/login.c @@ -50,6 +50,7 @@ void print_login_issue(const char *issue_file, const char *tty) outbuf = uts.sysname; break; case 'n': + case 'h': outbuf = uts.nodename; break; case 'r': @@ -72,10 +73,6 @@ void print_login_issue(const char *issue_file, const char *tty) case 't': strftime(buf, sizeof(buf), fmtstr_t, localtime(&t)); break; - case 'h': - gethostname(buf, sizeof(buf) - 1); - buf[sizeof(buf) - 1] = '\0'; - break; case 'l': outbuf = tty; break; @@ -91,13 +88,12 @@ void print_login_issue(const char *issue_file, const char *tty) void print_login_prompt(void) { - char buf[MAXHOSTNAMELEN+1]; - - if (gethostname(buf, MAXHOSTNAMELEN) == 0) - fputs(buf, stdout); - + char *hostname = safe_gethostname(); + + fputs(hostname, stdout); fputs(LOGIN, stdout); fflush(stdout); + free(hostname); } /* Clear dangerous stuff, set PATH */ diff --git a/libbb/obscure.c b/libbb/obscure.c index 5cc906235..1841b27d6 100644 --- a/libbb/obscure.c +++ b/libbb/obscure.c @@ -93,7 +93,7 @@ static const char *obscure_msg(const char *old_p, const char *new_p, const struc /* Add 2 for each type of characters to the minlen of password */ int size = CONFIG_PASSWORD_MINLEN + 8; const char *p; - char hostname[255]; + char *hostname; /* size */ if (!new_p || (length = strlen(new_p)) < CONFIG_PASSWORD_MINLEN) @@ -108,12 +108,11 @@ static const char *obscure_msg(const char *old_p, const char *new_p, const struc return "similar to gecos"; } /* hostname as-is, as sub-string, reversed, capitalized, doubled */ - if (gethostname(hostname, 255) == 0) { - hostname[254] = '\0'; - if (string_checker(new_p, hostname)) { - return "similar to hostname"; - } - } + hostname = safe_gethostname(); + i = string_checker(new_p, hostname); + free(hostname); + if (i) + return "similar to hostname"; /* Should / Must contain a mix of: */ for (i = 0; i < length; i++) { diff --git a/miscutils/devfsd.c b/miscutils/devfsd.c index 52a65bc98..286f00fd8 100644 --- a/miscutils/devfsd.c +++ b/miscutils/devfsd.c @@ -1133,8 +1133,8 @@ static void signal_handler(int sig) static const char *get_variable(const char *variable, void *info) { static char sbuf[sizeof(int)*3 + 2]; /* sign and NUL */ + static char *hostname; - char hostname[STRING_LENGTH]; struct get_variable_info *gv_info = info; const char *field_names[] = { "hostname", "mntpt", "devpath", "devname", @@ -1143,12 +1143,8 @@ static const char *get_variable(const char *variable, void *info) }; int i; - if (gethostname(hostname, STRING_LENGTH - 1) != 0) - /* Here on error we should do exit(RV_SYS_ERROR), instead we do exit(EXIT_FAILURE) */ - error_logger_and_die(LOG_ERR, "gethostname"); - - hostname[STRING_LENGTH - 1] = '\0'; - + if (!hostname) + hostname = safe_gethostname(); /* index_in_str_array returns i>=0 */ i = index_in_str_array(field_names, variable); diff --git a/networking/hostname.c b/networking/hostname.c index 2c224bef9..93cbc961f 100644 --- a/networking/hostname.c +++ b/networking/hostname.c @@ -24,8 +24,7 @@ static void do_sethostname(char *s, int isfile) if (sethostname(s, strlen(s)) < 0) { if (errno == EPERM) bb_error_msg_and_die(bb_msg_perm_denied_are_you_root); - else - bb_perror_msg_and_die("sethostname"); + bb_perror_msg_and_die("sethostname"); } } else { f = xfopen(s, "r"); @@ -54,27 +53,27 @@ int hostname_main(int argc, char **argv) OPT_dfis = 0xf, }; - char buf[256]; + char *buf; char *hostname_str; if (argc < 1) bb_show_usage(); getopt32(argv, "dfisF:", &hostname_str); + argv += optind; + buf = safe_gethostname(); /* Output in desired format */ if (option_mask32 & OPT_dfis) { struct hostent *hp; char *p; - gethostname(buf, sizeof(buf)); hp = xgethostbyname(buf); p = strchr(hp->h_name, '.'); if (option_mask32 & OPT_f) { puts(hp->h_name); } else if (option_mask32 & OPT_s) { - if (p != NULL) { + if (p) *p = '\0'; - } puts(hp->h_name); } else if (option_mask32 & OPT_d) { if (p) @@ -89,14 +88,15 @@ int hostname_main(int argc, char **argv) /* Set the hostname */ else if (option_mask32 & OPT_F) { do_sethostname(hostname_str, 1); - } else if (optind < argc) { - do_sethostname(argv[optind], 0); + } else if (argv[0]) { + do_sethostname(argv[0], 0); } /* Or if all else fails, * just print the current hostname */ else { - gethostname(buf, sizeof(buf)); puts(buf); } + if (ENABLE_FEATURE_CLEAN_UP) + free(buf); return 0; } diff --git a/sysklogd/syslogd.c b/sysklogd/syslogd.c index 0dc69d8cc..0d004bc27 100644 --- a/sysklogd/syslogd.c +++ b/sysklogd/syslogd.c @@ -97,8 +97,8 @@ struct globals { struct shbuf_ds *shbuf; #endif time_t last_log_time; - /* localhost's name */ - char localHostName[64]; + /* localhost's name. We print only first 64 chars */ + char *hostname; /* We recv into recvbuf... */ char recvbuf[MAX_READ]; @@ -416,7 +416,7 @@ static void timestamp_and_log(int pri, char *msg, int len) else { char res[20]; parse_fac_prio_20(pri, res); - sprintf(G.printbuf, "%s %s %s %s\n", timestamp, G.localHostName, res, msg); + sprintf(G.printbuf, "%s %.64s %s %s\n", timestamp, G.hostname, res, msg); } /* Log message locally (to file or shared mem) */ @@ -647,11 +647,8 @@ int syslogd_main(int argc, char **argv) option_mask32 |= OPT_locallog; /* Store away localhost's name before the fork */ - /* "It is unspecified whether the truncated hostname - * will be null-terminated". We give it (size - 1), - * thus last byte will be NUL no matter what. */ - gethostname(G.localHostName, sizeof(G.localHostName) - 1); - *strchrnul(G.localHostName, '.') = '\0'; + G.hostname = safe_gethostname(); + *strchrnul(G.hostname, '.') = '\0'; if (!(option_mask32 & OPT_nofork)) { bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv); -- cgit v1.2.3