#include <sys/sendfile.h> #include <sys/socket.h> #include <sys/types.h> #include <arpa/inet.h> #include <sys/mman.h> #include <sys/stat.h> #include <sys/wait.h> #include <pthread.h> #include <strings.h> #include <signal.h> #include <stdlib.h> #include <unistd.h> #include <string.h> #include <getopt.h> #include <fcntl.h> #include <stdio.h> #include <errno.h> #include <time.h> #include <pwd.h> /* Compile time constants */ #define FILED_SENDFILE_MAX 16777215 #define MAX_FAILURE_COUNT 30 /* Default values */ #define PORT 80 #define THREAD_COUNT 5 #define BIND_ADDR "::" #define CACHE_SIZE 8209 /* Arguments for worker threads */ struct filed_worker_thread_args { int fd; }; /* File information */ struct filed_fileinfo { pthread_mutex_t mutex; char *path; int fd; off_t len; char *lastmod; char lastmod_b[64]; char *type; }; /* Request variables */ struct filed_http_request { /** Buffers **/ struct filed_fileinfo fileinfo; char path_b[1010]; char tmpbuf[1010]; /** HTTP Request information **/ char *path; /*** Path being requested ***/ struct { struct { int present; off_t offset; /*** Range start ***/ off_t length; /*** Range length ***/ } range; } headers; }; /* Global variables */ /** Open File cache **/ struct filed_fileinfo *filed_fileinfo_fdcache = NULL; unsigned int filed_fileinfo_fdcache_size = 0; /* Initialize cache */ static int filed_init_cache(unsigned int cache_size) { unsigned int idx; int mutex_init_ret; /* Cache may not be re-initialized */ if (filed_fileinfo_fdcache_size != 0 || filed_fileinfo_fdcache != NULL) { return(1); } /* Allocate cache */ filed_fileinfo_fdcache_size = cache_size; filed_fileinfo_fdcache = malloc(sizeof(*filed_fileinfo_fdcache) * filed_fileinfo_fdcache_size); if (filed_fileinfo_fdcache == NULL) { return(1); } /* Initialize cache entries */ for (idx = 0; idx < filed_fileinfo_fdcache_size; idx++) { mutex_init_ret = pthread_mutex_init(&filed_fileinfo_fdcache[idx].mutex, NULL); if (mutex_init_ret != 0) { return(1); } filed_fileinfo_fdcache[idx].path = strdup(""); filed_fileinfo_fdcache[idx].fd = -1; filed_fileinfo_fdcache[idx].lastmod = ""; filed_fileinfo_fdcache[idx].type = ""; } return(0); } /* Initialize process */ static int filed_init(unsigned int cache_size) { static int called = 0; int cache_ret; if (called) { return(0); } called = 1; mlockall(MCL_CURRENT | MCL_FUTURE); signal(SIGPIPE, SIG_IGN); cache_ret = filed_init_cache(cache_size); if (cache_ret != 0) { return(cache_ret); } return(0); } /* Listen on a particular address/port */ static int filed_listen(const char *address, unsigned int port) { struct sockaddr_in6 addr; int pton_ret, bind_ret, listen_ret; int fd; addr.sin6_family = AF_INET6; addr.sin6_flowinfo = 0; addr.sin6_scope_id = 0; addr.sin6_port = htons(port); pton_ret = inet_pton(AF_INET6, address, addr.sin6_addr.s6_addr); if (pton_ret != 1) { return(-1); } fd = socket(AF_INET6, SOCK_STREAM, 0); if (fd < 0) { return(fd); } bind_ret = bind(fd, (const struct sockaddr *) &addr, sizeof(addr)); if (bind_ret < 0) { close(fd); return(-1); } listen_ret = listen(fd, 128); if (listen_ret != 0) { close(fd); return(-1); } return(fd); } /* Log a message */ //#define FILED_DONT_LOG #ifdef FILED_DONT_LOG # define filed_logging_thread_init() 0 # define filed_log_msg_debug(x, ...) /**/ # define filed_log_msg(x) /**/ #else /* Initialize logging thread */ static int filed_logging_thread_init(void) { /* XXX:TODO: Unimplemented */ return(0); } /* XXX:TODO: Unimplemented */ #define filed_log_msg_debug(x, ...) { fprintf(stderr, x, __VA_ARGS__); fprintf(stderr, "\n"); fflush(stderr); } static void filed_log_msg(const char *buffer) { /* XXX:TODO: Unimplemented */ fprintf(stderr, "%s\n", buffer); return; } #endif /* Format time per RFC2616 */ static char *filed_format_time(char *buffer, size_t buffer_len, const time_t timeinfo) { struct tm timeinfo_tm, *timeinfo_tm_p; timeinfo_tm_p = gmtime_r(&timeinfo, &timeinfo_tm); if (timeinfo_tm_p == NULL) { return("unknown"); } buffer[buffer_len - 1] = '\0'; buffer_len = strftime(buffer, buffer_len - 1, "%a, %d %b %Y %H:%M:%S GMT", timeinfo_tm_p); return(buffer); } /* hash */ /* XXX:TODO: Rewrite this */ static unsigned int filed_hash(const unsigned char *value, unsigned int modulus) { unsigned char curr, prev; int diff; unsigned int retval; retval = modulus - 1; prev = modulus % 255; while ((curr = *value)) { if (curr < 32) { curr = 255 - curr; } else { curr -= 32; } if (prev < curr) { diff = curr - prev; } else { diff = prev - curr; } retval <<= 3; retval ^= diff; value++; } retval = retval % modulus; return(retval); } /* Open a file and return file information */ static struct filed_fileinfo *filed_open_file(const char *path, struct filed_fileinfo *buffer) { struct filed_fileinfo *cache; unsigned int cache_idx; off_t len; int fd; cache_idx = filed_hash((const unsigned char *) path, filed_fileinfo_fdcache_size); cache = &filed_fileinfo_fdcache[cache_idx]; filed_log_msg_debug("Locking mutex for idx: %lu", (unsigned long) cache_idx); pthread_mutex_lock(&cache->mutex); filed_log_msg_debug("Completed locking mutex for idx: %lu", (unsigned long) cache_idx); if (strcmp(path, cache->path) != 0) { filed_log_msg_debug("Cache miss for idx: %lu: OLD \"%s\", NEW \"%s\"", (unsigned long) cache_idx, cache->path, path); fd = open(path, O_RDONLY | O_LARGEFILE); if (fd < 0) { pthread_mutex_unlock(&cache->mutex); return(NULL); } free(cache->path); if (cache->fd >= 0) { close(cache->fd); } len = lseek(fd, 0, SEEK_END); lseek(fd, 0, SEEK_SET); cache->fd = fd; cache->len = len; cache->path = strdup(path); /* XXX:TODO: Determine */ cache->type = "video/mp4"; cache->lastmod = filed_format_time(cache->lastmod_b, sizeof(cache->lastmod_b), time(NULL) - 30); } else { filed_log_msg_debug("Cache hit for idx: %lu: PATH \"%s\"", (unsigned long) cache_idx, path); } /* * We have to make a duplicate FD, because once we release the cache * mutex, the file descriptor may be closed */ fd = dup(cache->fd); if (fd < 0) { pthread_mutex_unlock(&cache->mutex); return(NULL); } buffer->fd = fd; buffer->len = cache->len; buffer->type = cache->type; memcpy(buffer->lastmod_b, cache->lastmod_b, sizeof(buffer->lastmod_b)); buffer->lastmod = buffer->lastmod_b + (cache->lastmod - cache->lastmod_b); pthread_mutex_unlock(&cache->mutex); return(buffer); } /* Process an HTTP request and return the path requested */ static struct filed_http_request *filed_get_http_request(FILE *fp, struct filed_http_request *buffer_st) { char *method, *path; char *buffer, *tmpbuffer, *workbuffer, *workbuffer_next; size_t buffer_len, tmpbuffer_len; off_t range_start, range_end, range_length; int range_request; int i; range_start = 0; range_end = 0; range_request = 0; range_length = -1; buffer = buffer_st->path_b; buffer_len = sizeof(buffer_st->path_b); tmpbuffer = buffer_st->tmpbuf; tmpbuffer_len = sizeof(buffer_st->tmpbuf); filed_log_msg("WAIT_FOR_REQUEST FD=..."); fgets(buffer, buffer_len, fp); method = buffer; buffer = strchr(buffer, ' '); if (buffer == NULL) { filed_log_msg("GOT_REQUEST FD=... ERROR=format"); return(NULL); } *buffer = '\0'; buffer++; path = buffer; buffer = strchr(buffer, ' '); if (buffer != NULL) { *buffer = '\0'; buffer++; } filed_log_msg("GOT_REQUEST FD=... PATH=..."); filed_log_msg("WAIT_FOR_HEADERS FD=..."); for (i = 0; i < 100; i++) { fgets(tmpbuffer, tmpbuffer_len, fp); if (strncasecmp(tmpbuffer, "Range: ", 7) == 0) { workbuffer = tmpbuffer + 7; if (strncasecmp(workbuffer, "bytes=", 6) == 0) { workbuffer += 6; range_request = 1; range_start = strtoull(workbuffer, &workbuffer_next, 10); workbuffer = workbuffer_next; if (*workbuffer == '-') { workbuffer++; if (*workbuffer != '\r' && *workbuffer != '\n') { range_end = strtoull(workbuffer, &workbuffer_next, 10); } } } } if (memcmp(tmpbuffer, "\r\n", 2) == 0) { break; } } filed_log_msg("GOT_HEADERS FD=..."); /* We only handle the "GET" method */ if (strcasecmp(method, "get") != 0) { return(NULL); } /* Determine range */ if (range_end != 0) { if (range_end <= range_start) { return(NULL); } range_length = range_end - range_start; filed_log_msg_debug("Computing length parameter: %llu = %llu - %llu", (unsigned long long) range_length, (unsigned long long) range_end, (unsigned long long) range_start ); } /* Fill up structure to return */ buffer_st->path = path; buffer_st->headers.range.present = range_request; buffer_st->headers.range.offset = range_start; buffer_st->headers.range.length = range_length; return(buffer_st); } /* Return an error page */ static void filed_error_page(FILE *fp, const char *date_current, int error_number) { char *error_string = "<html><head><title>ERROR</title></head><body>Unable to process request</body></html>"; fprintf(fp, "HTTP/1.1 %i OK\r\nDate: %s\r\nServer: filed\r\nLast-Modified: %s\r\nContent-Length: %llu\r\nContent-Type: %s\r\nConnection: close\r\n\r\n%s", error_number, date_current, date_current, (unsigned long long) strlen(error_string), "text/html", error_string ); } /* Handle a single request from a client */ static void filed_handle_client(int fd, struct filed_http_request *request) { struct filed_fileinfo *fileinfo; ssize_t sendfile_ret; size_t sendfile_len, sendfile_sent, sendfile_size; off_t sendfile_offset; char *path; char *date_current, date_current_b[64]; int http_code; FILE *fp; /* Determine current time */ date_current = filed_format_time(date_current_b, sizeof(date_current_b), time(NULL)); /* Open socket as ANSI I/O for ease of use */ fp = fdopen(fd, "w+b"); if (fp == NULL) { close(fd); return; } request = filed_get_http_request(fp, request); filed_log_msg("PROCESS_REPLY_START FD=... PATH=... RANGE_START=... RANGE_LENGTH=..."); if (request == NULL || request->path == NULL) { filed_error_page(fp, date_current, 500); filed_log_msg("PROCESS_REPLY_COMPLETE FD=... ERROR=500"); fclose(fp); return; } path = request->path; http_code = -1; fileinfo = filed_open_file(path, &request->fileinfo); if (fileinfo == NULL) { filed_error_page(fp, date_current, 404); filed_log_msg("PROCESS_REPLY_COMPLETE FD=... ERROR=404"); } else { if (request->headers.range.offset != 0 || request->headers.range.length >= 0) { if (request->headers.range.offset >= fileinfo->len) { filed_log_msg("PROCESS_REPLY_COMPLETE FD=... ERROR=416"); filed_error_page(fp, date_current, 416); } else { if (request->headers.range.length < 0) { filed_log_msg_debug("Computing length to fit in bounds: fileinfo->len = %llu, request->headers.range.offset = %llu", (unsigned long long) fileinfo->len, (unsigned long long) request->headers.range.offset ); request->headers.range.length = fileinfo->len - request->headers.range.offset; } filed_log_msg_debug("Partial request, starting at: %llu and running for %llu bytes", (unsigned long long) request->headers.range.offset, (unsigned long long) request->headers.range.length ); http_code = 206; } } else { if (request->headers.range.present) { http_code = 206; } else { http_code = 200; } request->headers.range.offset = 0; request->headers.range.length = fileinfo->len; } if (http_code > 0) { fprintf(fp, "HTTP/1.1 %i OK\r\nDate: %s\r\nServer: filed\r\nLast-Modified: %s\r\nContent-Length: %llu\r\nAccept-Ranges: bytes\r\nContent-Type: %s\r\nConnection: close\r\n", http_code, date_current, fileinfo->lastmod, (unsigned long long) request->headers.range.length, fileinfo->type ); if (http_code == 206) { fprintf(fp, "Content-Range: bytes %llu-%llu/%llu\r\n", (unsigned long long) request->headers.range.offset, (unsigned long long) (request->headers.range.offset + request->headers.range.length - 1), (unsigned long long) fileinfo->len ); } fprintf(fp, "\r\n"); fflush(fp); filed_log_msg("PROCESS_REPLY_COMPLETE FD=... STATUS=20X"); #ifdef FILED_NONBLOCK_HTTP int socket_flags; fd_set rfd, wfd; char sinkbuf[8192]; ssize_t read_ret; FD_ZERO(&rfd); FD_ZERO(&wfd); FD_SET(fd, &rfd); FD_SET(fd, &wfd); socket_flags = fcntl(fd, F_GETFL); fcntl(fd, F_SETFL, socket_flags | O_NONBLOCK); #endif filed_log_msg("SEND_START IFD=... OFD=... BYTES=..."); sendfile_offset = request->headers.range.offset; sendfile_len = request->headers.range.length; sendfile_sent = 0; while (1) { if (sendfile_len > FILED_SENDFILE_MAX) { sendfile_size = FILED_SENDFILE_MAX; } else { sendfile_size = sendfile_len; } sendfile_ret = sendfile(fd, fileinfo->fd, &sendfile_offset, sendfile_size); if (sendfile_ret <= 0) { #ifdef FILED_NONBLOCK_HTTP if (errno == EAGAIN) { sendfile_ret = 0; while (1) { select(fd + 1, &rfd, &wfd, NULL, NULL); if (FD_ISSET(fd, &rfd)) { read_ret = read(fd, sinkbuf, sizeof(sinkbuf)); if (read_ret <= 0) { break; } } if (FD_ISSET(fd, &wfd)) { read_ret = 1; break; } } if (read_ret <= 0) { break; } } else { break; } #else break; #endif } sendfile_len -= sendfile_ret; sendfile_sent += sendfile_ret; if (sendfile_len == 0) { break; } } filed_log_msg("SEND_COMPLETE STATUS=... IFD=... OFD=... BYTES=... BYTES_SENT=..."); } close(fileinfo->fd); filed_log_msg("CLOSE_FILE FD=..."); } filed_log_msg("CLOSE_CONNECTION FD=..."); fclose(fp); return; } /* Handle incoming connections */ static void *filed_worker_thread(void *arg_v) { struct filed_worker_thread_args *arg; struct filed_http_request request; struct sockaddr_in6 addr; socklen_t addrlen; int failure_count = 0, max_failure_count = MAX_FAILURE_COUNT; int master_fd, fd; /* Read arguments */ arg = arg_v; master_fd = arg->fd; while (1) { /* Failure loop prevention */ if (failure_count > max_failure_count) { break; } /* Accept a new client */ addrlen = sizeof(addr); fd = accept(master_fd, (struct sockaddr *) &addr, &addrlen); /* * If we fail, make a note of it so we don't go into a loop of * accept() failing */ if (fd < 0) { /* Log the new connection */ filed_log_msg("ACCEPT_FAILED"); failure_count++; continue; } /* Log the new connection */ filed_log_msg("NEW_CONNECTION SRC_ADDR=... SRC_PORT=... FD=..."); /* Reset failure count*/ failure_count = 0; /* Handle socket */ filed_handle_client(fd, &request); } /* Report error */ filed_log_msg("THREAD_DIED ABNORMAL"); return(NULL); } /* Create worker threads */ static int filed_worker_threads_init(int fd, int thread_count) { struct filed_worker_thread_args *arg; pthread_t threadid; int pthread_ret; int i; for (i = 0; i < thread_count; i++) { arg = malloc(sizeof(*arg)); arg->fd = fd; pthread_ret = pthread_create(&threadid, NULL, filed_worker_thread, arg); if (pthread_ret != 0) { return(-1); } } return(0); } /* Display help */ static void filed_print_help(FILE *output, int long_help, const char *extra) { if (extra) { fprintf(output, "%s\n", extra); } fprintf(output, "Usage: filed [<options>]\n"); fprintf(output, " Options:\n"); fprintf(output, " -h, --help\n"); fprintf(output, " -d, --daemon\n"); fprintf(output, " -b <address>, --bind <address>\n"); fprintf(output, " -p <port>, --port <port>\n"); fprintf(output, " -t <count>, --threads <count>\n"); fprintf(output, " -c <entries>, --cache <entries>\n"); fprintf(output, " -u <user>, --user <user>\n"); fprintf(output, " -r <directory>, --root <directory>\n"); if (long_help) { fprintf(output, "\n"); fprintf(output, " Usage:\n"); fprintf(output, " -h (or --help) prints this usage information\n"); fprintf(output, "\n"); fprintf(output, " -d (or --daemon) instructs filed to become a daemon after initializing\n"); fprintf(output, " the listening TCP socket and log files.\n"); fprintf(output, "\n"); fprintf(output, " -b (or --bind) specifies the address to listen for incoming HTTP\n"); fprintf(output, " requests on. The default value is \"%s\".\n", BIND_ADDR); fprintf(output, "\n"); fprintf(output, " -p (or --port) specifies the TCP port number to listen for incoming HTTP\n"); fprintf(output, " requests on. The default is %u.\n", (unsigned int) PORT); fprintf(output, "\n"); fprintf(output, " -t (or --threads) specifies the number of worker threads to create. Each\n"); fprintf(output, " worker thread can service one concurrent HTTP session.\n"); fprintf(output, " Thus the number of threads created will determine how\n"); fprintf(output, " many simultaneous transfers will be possible. The\n"); fprintf(output, " default is %lu.\n", (unsigned long) THREAD_COUNT); fprintf(output, "\n"); fprintf(output, " -c (or --cache) specifies the number of file information cache entries\n"); fprintf(output, " to allocate. Each cache entry holds file information as\n"); fprintf(output, " well as an open file descriptor to the file, so resource\n"); fprintf(output, " limits (i.e., ulimit) should be considered. This should\n"); fprintf(output, " be a prime number for ideal use with the lookup method.\n"); fprintf(output, " The default is %lu.\n", (unsigned long) CACHE_SIZE); fprintf(output, "\n"); fprintf(output, " -u (or --user) specifies the user to switch user IDs to before servicing\n"); fprintf(output, " requests. The default is not change user IDs.\n"); fprintf(output, "\n"); fprintf(output, " -r (or --root) specifies the directory to act as the root directory for\n"); fprintf(output, " the file server. If this option is specified, chroot(2)\n"); fprintf(output, " is called. The default is not change root directories,\n"); fprintf(output, " that is, the \"/\" directory is shared out. This will\n"); fprintf(output, " likely be a security issue, so this option should always\n"); fprintf(output, " be used.\n"); } return; } /* Add a getopt option */ static void filed_getopt_long_setopt(struct option *opt, const char *name, int has_arg, int val) { opt->name = name; opt->has_arg = has_arg; opt->flag = NULL; opt->val = val; return; } /* Resolve a username to a UID */ static int filed_user_lookup(const char *user, uid_t *user_id) { char *next; uid_t user_id_check; #ifndef FILED_NO_GETPWNAM struct passwd *ent; ent = getpwnam(user); if (ent != NULL) { *user_id = ent->pw_uid; return(0); } #endif user_id_check = strtoull(user, &next, 10); if (next == NULL) { return(1); } if (next[0] != '\0') { return(1); } *user_id = user_id_check; return(0); } /* Daemonize */ static int filed_daemonize(void) { pid_t setsid_ret, fork_ret; int chdir_ret, dup2_ret; int fd_in, fd_out; chdir_ret = chdir("/"); if (chdir_ret != 0) { return(1); } fork_ret = fork(); if (fork_ret < 0) { return(1); } if (fork_ret > 0) { /* Parent */ waitpid(fork_ret, NULL, 0); exit(EXIT_SUCCESS); } /* Child */ if (fork() != 0) { /* Child */ exit(EXIT_SUCCESS); } /* Grand child */ setsid_ret = setsid(); if (setsid_ret == ((pid_t) -1)) { return(1); } fd_in = open("/dev/null", O_RDONLY); fd_out = open("/dev/null", O_WRONLY); if (fd_in < 0 || fd_out < 0) { return(1); } dup2_ret = dup2(fd_in, STDIN_FILENO); if (dup2_ret != STDIN_FILENO) { return(1); } dup2_ret = dup2(fd_out, STDOUT_FILENO); if (dup2_ret != STDOUT_FILENO) { return(1); } dup2_ret = dup2(fd_out, STDERR_FILENO); if (dup2_ret != STDERR_FILENO) { return(1); } close(fd_in); close(fd_out); return(0); } /* Run process */ int main(int argc, char **argv) { struct option options[9]; const char *bind_addr = BIND_ADDR, *newroot = NULL; uid_t user = 0; int port = PORT, thread_count = THREAD_COUNT; int cache_size = CACHE_SIZE; int init_ret, chroot_ret, setuid_ret, lookup_ret, chdir_ret; int setuid_enabled = 0, daemon_enabled = 0; int ch; int fd; /* Process arguments */ filed_getopt_long_setopt(&options[0], "port", required_argument, 'p'); filed_getopt_long_setopt(&options[1], "threads", required_argument, 't'); filed_getopt_long_setopt(&options[2], "cache", required_argument, 'c'); filed_getopt_long_setopt(&options[3], "bind", required_argument, 'b'); filed_getopt_long_setopt(&options[4], "user", required_argument, 'u'); filed_getopt_long_setopt(&options[5], "root", required_argument, 'r'); filed_getopt_long_setopt(&options[6], "help", no_argument, 'h'); filed_getopt_long_setopt(&options[7], "daemon", no_argument, 'd'); filed_getopt_long_setopt(&options[8], NULL, 0, 0); while ((ch = getopt_long(argc, argv, "p:t:c:b:u:r:hd", options, NULL)) != -1) { switch(ch) { case 'p': port = atoi(optarg); break; case 't': thread_count = atoi(optarg); break; case 'c': cache_size = atoi(optarg); break; case 'b': bind_addr = strdup(optarg); break; case 'u': setuid_enabled = 1; lookup_ret = filed_user_lookup(optarg, &user); if (lookup_ret != 0) { filed_print_help(stderr, 0, "Invalid username specified"); return(1); } break; case 'r': newroot = strdup(optarg); break; case 'd': daemon_enabled = 1; break; case '?': case ':': filed_print_help(stderr, 0, NULL); return(1); case 'h': filed_print_help(stdout, 1, NULL); return(0); } } /* Create listening socket */ fd = filed_listen(bind_addr, port); if (fd < 0) { perror("filed_listen"); return(1); } /* Chroot, if appropriate */ if (newroot) { chdir_ret = chdir(newroot); if (chdir_ret != 0) { perror("chdir"); return(1); } chroot_ret = chroot("."); if (chroot_ret != 0) { perror("chroot"); return(1); } } /* Drop privileges, if appropriate */ if (setuid_enabled) { setuid_ret = setuid(user); if (setuid_ret != 0) { perror("setuid"); return(1); } } /* Become a daemon */ if (daemon_enabled) { filed_daemonize(); } /* Initialize */ init_ret = filed_init(cache_size); if (init_ret != 0) { perror("filed_init"); return(3); } /* Create logging thread */ init_ret = filed_logging_thread_init(); if (init_ret != 0) { perror("filed_logging_thread_init"); return(4); } /* Create worker threads */ init_ret = filed_worker_threads_init(fd, thread_count); if (init_ret != 0) { perror("filed_worker_threads_init"); return(4); } /* Wait for threads to exit */ /* XXX:TODO: Monitor thread usage */ while (1) { sleep(60); } /* Return in failure */ return(2); }