diff options
Diffstat (limited to 'src/utils.c')
| -rw-r--r-- | src/utils.c | 367 |
1 files changed, 189 insertions, 178 deletions
diff --git a/src/utils.c b/src/utils.c index 1a91d7a..63f4dbb 100644 --- a/src/utils.c +++ b/src/utils.c @@ -1,9 +1,9 @@ -/* $Id: utils.c,v 1.1.1.1 2000-02-16 17:32:24 sdyoung Exp $ +/* $Id: utils.c,v 1.2 2000-09-12 00:01:29 rjkaes Exp $ * * Misc. routines which are used by the various functions to handle strings * and memory allocation and pretty much anything else we can think of. Also, - * the load cutoff routine is in here, along with the HTML show stats - * function. Could not think of a better place for it, so it's in here. + * the load cutoff routine is in here. Could not think of a better place for + * it, so it's in here. * * Copyright (C) 1998 Steven Young * Copyright (C) 1999 Robert James Kaes (rjkaes@flarenet.com) @@ -19,60 +19,27 @@ * General Public License for more details. */ -#ifdef HAVE_CONFIG_H -#include <defines.h> -#endif +#include "tinyproxy.h" -#include <stdio.h> -#include <string.h> -#include <stdlib.h> -#include <unistd.h> -#include <time.h> #include <ctype.h> -#include <sysexits.h> -#include <sys/types.h> -#include <sys/socket.h> -#include <errno.h> #include <signal.h> -#include <sys/stat.h> -#include <assert.h> +#include <sysexits.h> -#include "config.h" -#include "tinyproxy.h" -#include "utils.h" -#include "log.h" -#include "conns.h" #include "buffer.h" - -char *xstrdup(char *st) -{ - char *p; - - assert(st); - - if (!(p = strdup(st))) { - log("ERROR xstrdup: out of memory (%s)", strerror(errno)); - return NULL; - } else { - return p; - } -} +#include "log.h" +#include "sock.h" +#include "utils.h" /* * Find the start of the needle in the haystack. Limits the search to less * than "length" characters. Returns NULL if the needle is not found. */ -char *xstrstr(char *haystack, char *needle, unsigned int length, - int case_sensitive) +char *xstrstr(char *haystack, char *needle, size_t length, + bool_t case_sensitive) { unsigned int i; /* Used to specify which function to use... need the decl. */ - int (*fn) (const char *s1, const char *s2, unsigned int n); - - assert(haystack); - assert(needle); - assert(length > 0); - assert(case_sensitive == FALSE || case_sensitive == TRUE); + int (*fn) (const char *s1, const char *s2, size_t n); if (case_sensitive) fn = strncmp; @@ -84,7 +51,7 @@ char *xstrstr(char *haystack, char *needle, unsigned int length, for (i = 0; i <= length - strlen(needle); i++) { if ((*fn) (haystack + i, needle, strlen(needle)) == 0) - return haystack + i; + return (haystack + i); } @@ -92,173 +59,217 @@ char *xstrstr(char *haystack, char *needle, unsigned int length, } /* - * for-sure malloc + * Display an error to the client. */ -void *xmalloc(unsigned long int sz) -{ - void *p; - - assert(sz > 0); - - if (!(p = malloc((size_t) sz))) { - log("ERROR xmalloc: out of memory (%s)", strerror(errno)); - return NULL; - } - return p; -} - -#ifdef USE_PROC -int calcload(void) +int httperr(struct conn_s *connptr, int err, char *msg) { - char buf[BUFFER], *p; - FILE *f; + static char *premsg = "HTTP/1.0 %d %s\r\n" \ + "Content-type: text/html\r\n\r\n" \ + "<html><head><title>%s</title></head>\r\n" \ + "<body>\r\n" \ + "<font size=\"+2\">Cache Error!</font><br>\r\n" \ + "An error of type %d occurred: %s\r\n" \ + "<hr>\r\n" \ + "<font size=\"-1\"><em>Generated by %s</em></font>\r\n" \ + "</body></html>\r\n"; - if (!config.cutoffload) { + connptr->output_message = malloc(MAXBUFFSIZE); + if (!connptr->output_message) { + log(LOG_CRIT, "Out of memory!"); return -1; } - if (!(f = fopen("/proc/loadavg", "rt"))) { - log("unable to read /proc/loadavg"); - config.cutoffload = 0.0; - return -1; - } - fgets(buf, BUFFER, f); - p = strchr(buf, ' '); - *p = '\0'; - load = atof(buf); - fclose(f); + sprintf(connptr->output_message, premsg, err, msg, msg, err, msg, VERSION); + return 0; } -#else -int calcload(void) +void makedaemon(void) { - FILE *f; - char buf[BUFFER]; - char *p, *y; + if (fork() != 0) + exit(0); - if (!config.cutoffload) { - return -1; - } + setsid(); + signal(SIGHUP, SIG_IGN); - if (!(f = popen(UPTIME_PATH, "r"))) { - log("calcload: unable to exec uptime"); - config.cutoffload = 0.0; - return -1; - } - fgets(buf, BUFFER, f); - p = strrchr(buf, ':'); - p += 2; - y = strchr(p, ','); - *y = '\0'; - load = atof(p); - pclose(f); - return 0; -} + if (fork() != 0) + exit(0); -#endif + chdir("/"); + umask(077); + + close(0); + close(1); + close(2); +} /* - * Delete the server's buffer and replace it with a premade message which will - * be sent to the client. + * Safely creates filename and returns the low-level file descriptor. */ -static void update_output_buffer(struct conn_s *connptr, char *outbuf) +static int create_file_safely(const char *filename) { - assert(connptr); - assert(outbuf); - - delete_buffer(connptr->sbuffer); - connptr->sbuffer = new_buffer(); + struct stat lstatinfo; + int fildes; + + /* + * lstat() the file. If it doesn't exist, create it with O_EXCL. + * If it does exist, open it for writing and perform the fstat() + * check. + */ + if (lstat(filename, &lstatinfo) < 0) { + /* + * If lstat() failed for any reason other than "file not + * existing", exit. + */ + if (errno != ENOENT) { + log(LOG_ERR, "Error checking PID file %s: %s", + filename, strerror(errno)); + return -1; + } + + /* + * The file doesn't exist, so create it with O_EXCL to make + * sure an attacker can't slip in a file between the lstat() + * and open() + */ + if ((fildes = open(filename, O_RDWR | O_CREAT | O_EXCL, 0600)) < 0) { + log(LOG_ERR, "Could not create PID file %s: %s", + filename, strerror(errno)); + return -1; + } + } else { + struct stat fstatinfo; + + /* + * Open an existing file. + */ + if ((fildes = open(filename, O_RDWR)) < 0) { + log(LOG_ERR, "Could not open PID file %s: %s", + filename, strerror(errno)); + return -1; + } + + /* + * fstat() the opened file and check that the file mode bits, + * inode, and device match. + */ + if (fstat(fildes, &fstatinfo) < 0 + || lstatinfo.st_mode != fstatinfo.st_mode + || lstatinfo.st_ino != fstatinfo.st_ino + || lstatinfo.st_dev != fstatinfo.st_dev) { + log(LOG_ERR, "The PID file %s has been changed before it could be opened!", + filename); + close(fildes); + return -1; + } + + /* + * If the above check was passed, we know that the lstat() + * and fstat() were done on the same file. Now we check that + * there's only one link, and that it's a normal file (this + * isn't strictly necessary because the fstat() vs lstat() + * st_mode check would also find this) + */ + if (fstatinfo.st_nlink > 1 || !S_ISREG(lstatinfo.st_mode)) { + log(LOG_ERR, "The PID file %s has too many links, or is not a regular file: %s", + filename, strerror(errno)); + close(fildes); + return -1; + } + + /* + * On systems whcih don't support ftruncate() the best we can + * do is to close the file and reopen it in create mode, which + * unfortunately leads to a race condition, however "systems + * which don't support ftruncate()" is pretty much SCO only, + * and if you're using that you deserver what you get. + * ("Little sympathy has been extended") + */ +#if defined NO_FTRUNCATE + close(fildes); + if ((fildes = open(filename, O_RDWR | O_CREAT | O_TRUNC, 0600)) < 0) { + log(LOG_ERR, "Could not open PID file %s: %s", + filename, strerror(errno)); + return -1; + } +#else + ftruncate(fildes, 0); +#endif /* NO_FTRUNCATE */ + } - push_buffer(connptr->sbuffer, outbuf, strlen(outbuf)); - shutdown(connptr->server_fd, 2); - connptr->type = CLOSINGCONN; + return fildes; } /* - * Display the statics of the tinyproxy server. + * Write the PID of the program to the specified file. */ -int showstats(struct conn_s *connptr) +void pidfile_create(const char *filename) { - char *outbuf; - static char *msg = "HTTP/1.0 200 OK\r\n" \ - "Content-type: text/html\r\n\r\n" \ - "<html><head><title>%s stats</title></head>\r\n" \ - "<body>\r\n" \ - "<center><h2>%s run-time statistics</h2></center><hr>\r\n" \ - "<blockquote>\r\n" \ - "Number of requests: %lu<br>\r\n" \ - "Number of connections: %lu<br>\r\n" \ - "Number of bad connections: %lu<br>\r\n" \ - "Number of opens: %lu<br>\r\n" \ - "Number of listens: %lu<br>\r\n" \ - "Number of bytes (tx): %lu<br>\r\n" \ - "Number of bytes (rx): %lu<br>\r\n" \ - "Number of garbage collects:%lu<br>\r\n" \ - "Number of idle connection kills:%lu<br>\r\n" \ - "Number of refused connections due to high load:%lu<br>\r\n" \ - "Current system load average:%.2f" \ - "(recalculated every % lu seconds)<br>\r\n" \ - "</blockquote>\r\n</body></html>\r\n"; - - assert(connptr); - - outbuf = xmalloc(BUFFER); - - sprintf(outbuf, msg, VERSION, VERSION, stats.num_reqs, - stats.num_cons, stats.num_badcons, stats.num_opens, - stats.num_listens, stats.num_tx, stats.num_rx, - stats.num_garbage, stats.num_idles, stats.num_refused, load, - LOAD_RECALCTIMER); - - update_output_buffer(connptr, outbuf); + int fildes; + FILE *fd; + + /* + * Create a new file + */ + if ((fildes = create_file_safely(filename)) < 0) + exit(1); + + /* + * Open a stdio file over the low-level one. + */ + if ((fd = fdopen(fildes, "w")) == NULL) { + log(LOG_ERR, "fdopen() error on PID file %s: %s", + filename, strerror(errno)); + close(fildes); + unlink(filename); + exit(1); + } - return 0; + fprintf(fd, "%ld\n", (long)getpid()); + fclose(fd); } +#ifndef HAVE_STRLCPY /* - * Display an error to the client. + * Function API taken from OpenBSD. Like strncpy(), but does not 0 fill the + * buffer, and always NULL terminates the buffer. size is the size of the + * destination buffer. */ -int httperr(struct conn_s *connptr, int err, char *msg) +size_t strlcpy(char *dst, const char *src, size_t size) { - char *outbuf; - static char *premsg = "HTTP/1.0 %d %s\r\n" \ - "Content-type: text/html\r\n\r\n" \ - "<html><head><title>%s</title></head>\r\n" \ - "<body>\r\n" \ - "<font size=\"+2\">Cache Error!</font><br>\r\n" \ - "An error of type %d occurred: %s\r\n" \ - "<hr>\r\n" \ - "<font size=\"-1\"><em>Generated by %s</em></font>\r\n" \ - "</body></html>\r\n"; + size_t len = strlen(src); + size_t ret = len; - assert(connptr); - assert(err > 0); - assert(msg); + if (len >= size) + len = size - 1; - outbuf = xmalloc(BUFFER); - sprintf(outbuf, premsg, err, msg, msg, err, msg, VERSION); + memcpy(dst, src, len); + dst[len] = '\0'; - update_output_buffer(connptr, outbuf); - - return 0; + return ret; } +#endif -void makedaemon(void) +#ifndef HAVE_STRLCAT +/* + * Function API taken from OpenBSD. Like strncat(), but does not 0 fill the + * buffer, and always NULL terminates the buffer. size is the length of the + * buffer, which should be one more than the maximum resulting string + * length. + */ +size_t strlcat(char *dst, const char *src, size_t size) { - if (fork() != 0) - exit(0); - - setsid(); - signal(SIGHUP, SIG_IGN); - - if (fork() != 0) - exit(0); - - chdir("/"); - umask(0); + size_t len1 = strlen(dst); + size_t len2 = strlen(src); + size_t ret = len1 + len2; + + if (len1 + len2 >= size) + len2 = size - len1 - 1; + if (len2 > 0) { + memcpy(dst + len1, src, len2); + dst[len1 + len2] = '\0'; + } - close(0); - close(1); - close(2); + return ret; } +#endif |