/* $FreeBSD: rev 267127 $ */ /* $NetBSD: http.c,v 1.37 2014/06/11 13:12:12 joerg Exp $ */ /*- * Copyright (c) 2000-2014 Dag-Erling Smorgrav * Copyright (c) 2003 Thomas Klausner * Copyright (c) 2008, 2009 Joerg Sonnenberger * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer * in this position and unchanged. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* * The following copyright applies to the base64 code: * *- * Copyright 1997 Massachusetts Institute of Technology * * Permission to use, copy, modify, and distribute this software and * its documentation for any purpose and without fee is hereby * granted, provided that both the above copyright notice and this * permission notice appear in all copies, that both the above * copyright notice and this permission notice appear in all * supporting documentation, and that the name of M.I.T. not be used * in advertising or publicity pertaining to distribution of the * software without specific, written prior permission. M.I.T. makes * no representations about the suitability of this software for any * purpose. It is provided "as is" without express or implied * warranty. * * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #if defined(__linux__) #define _GNU_SOURCE #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "fetch.h" #include "common.h" #include "httperr.h" /* Maximum number of redirects to follow */ #define MAX_REDIRECT 5 /* Symbolic names for reply codes we care about */ #define HTTP_OK 200 #define HTTP_PARTIAL 206 #define HTTP_MOVED_PERM 301 #define HTTP_MOVED_TEMP 302 #define HTTP_SEE_OTHER 303 #define HTTP_NOT_MODIFIED 304 #define HTTP_USE_PROXY 305 #define HTTP_TEMP_REDIRECT 307 #define HTTP_PERM_REDIRECT 308 #define HTTP_NEED_AUTH 401 #define HTTP_NEED_PROXY_AUTH 407 #define HTTP_BAD_RANGE 416 #define HTTP_PROTOCOL_ERROR 999 #define HTTP_REDIRECT(xyz) ((xyz) == HTTP_MOVED_PERM \ || (xyz) == HTTP_MOVED_TEMP \ || (xyz) == HTTP_TEMP_REDIRECT \ || (xyz) == HTTP_USE_PROXY \ || (xyz) == HTTP_SEE_OTHER) #define HTTP_ERROR(xyz) ((xyz) > 400 && (xyz) < 599) static int http_cmd(conn_t *, const char *, ...) LIBFETCH_PRINTFLIKE(2, 3); /***************************************************************************** * I/O functions for decoding chunked streams */ struct httpio { conn_t *conn; /* connection */ int chunked; /* chunked mode */ int keep_alive; /* keep-alive mode */ char *buf; /* chunk buffer */ size_t bufsize; /* size of chunk buffer */ ssize_t buflen; /* amount of data currently in buffer */ int bufpos; /* current read offset in buffer */ int eof; /* end-of-file flag */ int error; /* error flag */ size_t chunksize; /* remaining size of current chunk */ off_t contentlength; /* remaining size of the content */ }; /* * Get next chunk header */ static int http_new_chunk(struct httpio *io) { char *p; if (fetch_getln(io->conn) == -1) return (-1); if (io->conn->buflen < 2 || !isxdigit((unsigned char)*io->conn->buf)) return (-1); for (p = io->conn->buf; *p && !isspace((unsigned char)*p); ++p) { if (*p == ';') break; if (!isxdigit((unsigned char)*p)) return (-1); if (isdigit((unsigned char)*p)) { io->chunksize = io->chunksize * 16 + *p - '0'; } else { io->chunksize = io->chunksize * 16 + 10 + tolower((unsigned char)*p) - 'a'; } } return (io->chunksize); } /* * Grow the input buffer to at least len bytes */ static int http_growbuf(struct httpio *io, size_t len) { char *tmp; if (io->bufsize >= len) return (0); if ((tmp = realloc(io->buf, len)) == NULL) return (-1); io->buf = tmp; io->bufsize = len; return (0); } /* * Fill the input buffer, do chunk decoding on the fly */ static int http_fillbuf(struct httpio *io, size_t len) { if (io->error) return (-1); if (io->eof) return (0); if (io->contentlength >= 0 && (off_t)len > io->contentlength) len = io->contentlength; if (io->chunked == 0) { if (http_growbuf(io, len) == -1) return (-1); if ((io->buflen = fetch_read(io->conn, io->buf, len)) == -1) { io->error = 1; return (-1); } if (io->contentlength) io->contentlength -= io->buflen; io->bufpos = 0; return (io->buflen); } if (io->chunksize == 0) { switch (http_new_chunk(io)) { case -1: io->error = 1; return (-1); case 0: io->eof = 1; if (fetch_getln(io->conn) == -1) return (-1); return (0); } } if (len > io->chunksize) len = io->chunksize; if (http_growbuf(io, len) == -1) return (-1); if ((io->buflen = fetch_read(io->conn, io->buf, len)) == -1) { io->error = 1; return (-1); } io->chunksize -= io->buflen; if (io->contentlength >= 0) io->contentlength -= io->buflen; if (io->chunksize == 0) { char endl[2]; ssize_t len2; len2 = fetch_read(io->conn, endl, 2); if (len2 == 1 && fetch_read(io->conn, endl + 1, 1) != 1) return (-1); if (len2 == -1 || endl[0] != '\r' || endl[1] != '\n') return (-1); } io->bufpos = 0; return (io->buflen); } /* * Read function */ static ssize_t http_readfn(void *v, void *buf, size_t len) { struct httpio *io = (struct httpio *)v; size_t l, pos; if (io->error) return (-1); if (io->eof) return (0); for (pos = 0; len > 0; pos += l, len -= l) { /* empty buffer */ if (!io->buf || io->bufpos == io->buflen) if (http_fillbuf(io, len) < 1) break; if (!io->buf) return -1; l = io->buflen - io->bufpos; if (len < l) l = len; memcpy((char *)buf + pos, io->buf + io->bufpos, l); io->bufpos += l; } if (!pos && io->error) return (-1); return (pos); } /* * Write function */ static ssize_t http_writefn(void *v, const void *buf, size_t len) { struct httpio *io = (struct httpio *)v; return (fetch_write(io->conn, buf, len)); } /* * Close function */ static void http_closefn(void *v) { struct httpio *io = (struct httpio *)v; if (io->keep_alive) { int val; val = 0; setsockopt(io->conn->sd, IPPROTO_TCP, TCP_NODELAY, &val, sizeof(val)); fetch_cache_put(io->conn, fetch_close); #ifdef TCP_NOPUSH val = 1; setsockopt(io->conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, sizeof(val)); #endif } else { fetch_close(io->conn); } free(io->buf); free(io); } /* * Wrap a file descriptor up */ static fetchIO * http_funopen(conn_t *conn, int chunked, int keep_alive, off_t clength) { struct httpio *io; fetchIO *f; if ((io = calloc(1, sizeof(*io))) == NULL) { fetch_syserr(); return (NULL); } io->conn = conn; io->chunked = chunked; io->contentlength = clength; io->keep_alive = keep_alive; f = fetchIO_unopen(io, http_readfn, http_writefn, http_closefn); if (f == NULL) { fetch_syserr(); free(io); return (NULL); } return (f); } /***************************************************************************** * Helper functions for talking to the server and parsing its replies */ /* Header types */ typedef enum { hdr_syserror = -2, hdr_error = -1, hdr_end = 0, hdr_unknown = 1, hdr_connection, hdr_content_length, hdr_content_range, hdr_last_modified, hdr_location, hdr_transfer_encoding, hdr_www_authenticate } hdr_t; /* Names of interesting headers */ static struct { hdr_t num; const char *name; } hdr_names[] = { { hdr_connection, "Connection" }, { hdr_content_length, "Content-Length" }, { hdr_content_range, "Content-Range" }, { hdr_last_modified, "Last-Modified" }, { hdr_location, "Location" }, { hdr_transfer_encoding, "Transfer-Encoding" }, { hdr_www_authenticate, "WWW-Authenticate" }, { hdr_unknown, NULL }, }; /* * Send a formatted line; optionally echo to terminal */ LIBFETCH_PRINTFLIKE(2, 3) static int http_cmd(conn_t *conn, const char *fmt, ...) { va_list ap; size_t len; char *msg; int r; va_start(ap, fmt); len = vasprintf(&msg, fmt, ap); va_end(ap); if (msg == NULL) { errno = ENOMEM; fetch_syserr(); return (-1); } r = fetch_write(conn, msg, len); free(msg); if (r == -1) { fetch_syserr(); return (-1); } return (0); } /* * Get and parse status line */ static int http_get_reply(conn_t *conn) { char *p; if (fetch_getln(conn) == -1) return (-1); /* * A valid status line looks like "HTTP/m.n xyz reason" where m * and n are the major and minor protocol version numbers and xyz * is the reply code. * Unfortunately, there are servers out there (NCSA 1.5.1, to name * just one) that do not send a version number, so we can't rely * on finding one, but if we do, insist on it being 1.0 or 1.1. * We don't care about the reason phrase. */ if (strncmp(conn->buf, "HTTP", 4) != 0) return (HTTP_PROTOCOL_ERROR); p = conn->buf + 4; if (*p == '/') { if (p[1] != '1' || p[2] != '.' || (p[3] != '0' && p[3] != '1')) return (HTTP_PROTOCOL_ERROR); p += 4; } if (*p != ' ' || !isdigit((unsigned char)p[1]) || !isdigit((unsigned char)p[2]) || !isdigit((unsigned char)p[3])) return (HTTP_PROTOCOL_ERROR); conn->err = (p[1] - '0') * 100 + (p[2] - '0') * 10 + (p[3] - '0'); return (conn->err); } /* * Check a header; if the type matches the given string, return a pointer * to the beginning of the value. */ static const char * http_match(const char *str, const char *hdr) { while (*str && *hdr && tolower((unsigned char)*str++) == tolower((unsigned char)*hdr++)) /* nothing */; if (*str || *hdr != ':') return (NULL); while (*hdr && isspace((unsigned char)*++hdr)) /* nothing */; return (hdr); } /* * Get the next header and return the appropriate symbolic code. */ static hdr_t http_next_header(conn_t *conn, const char **p) { int i; if (fetch_getln(conn) == -1) return (hdr_syserror); while (conn->buflen && isspace((unsigned char)conn->buf[conn->buflen - 1])) conn->buflen--; conn->buf[conn->buflen] = '\0'; if (conn->buflen == 0) return (hdr_end); /* * We could check for malformed headers but we don't really care. * A valid header starts with a token immediately followed by a * colon; a token is any sequence of non-control, non-whitespace * characters except "()<>@,;:\\\"{}". */ for (i = 0; hdr_names[i].num != hdr_unknown; i++) if ((*p = http_match(hdr_names[i].name, conn->buf)) != NULL) return (hdr_names[i].num); return (hdr_unknown); } /* * Parse a last-modified header */ static int http_parse_mtime(const char *p, time_t *mtime) { char locale[64], *r; struct tm tm; strncpy(locale, setlocale(LC_TIME, NULL), sizeof(locale)-1); locale[sizeof(locale)-1] = '\0'; setlocale(LC_TIME, "C"); r = strptime(p, "%a, %d %b %Y %H:%M:%S GMT", &tm); /* * Some proxies use UTC in response, but it should still be * parsed. RFC2616 states GMT and UTC are exactly equal for HTTP. */ if (r == NULL) r = strptime(p, "%a, %d %b %Y %H:%M:%S UTC", &tm); /* XXX should add support for date-2 and date-3 */ setlocale(LC_TIME, locale); if (r == NULL) return (-1); *mtime = timegm(&tm); return (0); } /* * Parse a content-length header */ static int http_parse_length(const char *p, off_t *length) { off_t len; for (len = 0; *p && isdigit((unsigned char)*p); ++p) len = len * 10 + (*p - '0'); if (*p) return (-1); *length = len; return (0); } /* * Parse a content-range header */ static int http_parse_range(const char *p, off_t *offset, off_t *length, off_t *size) { off_t first, last, len; if (strncasecmp(p, "bytes ", 6) != 0) return (-1); p += 6; if (*p == '*') { first = last = -1; ++p; } else { for (first = 0; *p && isdigit((unsigned char)*p); ++p) first = first * 10 + *p - '0'; if (*p != '-') return (-1); for (last = 0, ++p; *p && isdigit((unsigned char)*p); ++p) last = last * 10 + *p - '0'; } if (first > last || *p != '/') return (-1); for (len = 0, ++p; *p && isdigit((unsigned char)*p); ++p) len = len * 10 + *p - '0'; if (*p || len < last - first + 1) return (-1); if (first == -1) *length = 0; else *length = last - first + 1; *offset = first; *size = len; return (0); } /***************************************************************************** * Helper functions for authorization */ /* * Base64 encoding */ static char * http_base64(const char *src) { static const char base64[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" "abcdefghijklmnopqrstuvwxyz" "0123456789+/"; char *str, *dst; size_t l; int t, r; l = strlen(src); if ((str = malloc(((l + 2) / 3) * 4 + 1)) == NULL) return (NULL); dst = str; r = 0; while (l >= 3) { t = (src[0] << 16) | (src[1] << 8) | src[2]; dst[0] = base64[(t >> 18) & 0x3f]; dst[1] = base64[(t >> 12) & 0x3f]; dst[2] = base64[(t >> 6) & 0x3f]; dst[3] = base64[(t >> 0) & 0x3f]; src += 3; l -= 3; dst += 4; r += 4; } switch (l) { case 2: t = (src[0] << 16) | (src[1] << 8); dst[0] = base64[(t >> 18) & 0x3f]; dst[1] = base64[(t >> 12) & 0x3f]; dst[2] = base64[(t >> 6) & 0x3f]; dst[3] = '='; dst += 4; r += 4; break; case 1: t = src[0] << 16; dst[0] = base64[(t >> 18) & 0x3f]; dst[1] = base64[(t >> 12) & 0x3f]; dst[2] = dst[3] = '='; dst += 4; r += 4; break; case 0: break; } *dst = 0; return (str); } /* * Encode username and password */ static int http_basic_auth(conn_t *conn, const char *hdr, const char *usr, const char *pwd) { char *upw, *auth; int r; if (asprintf(&upw, "%s:%s", usr, pwd) == -1) return (-1); auth = http_base64(upw); free(upw); if (auth == NULL) return (-1); r = http_cmd(conn, "%s: Basic %s\r\n", hdr, auth); free(auth); return (r); } /* * Send an authorization header */ static int http_authorize(conn_t *conn, const char *hdr, const char *p) { /* basic authorization */ if (strncasecmp(p, "basic:", 6) == 0) { char *user, *pwd, *str; int r; /* skip realm */ for (p += 6; *p && *p != ':'; ++p) /* nothing */ ; if (!*p || strchr(++p, ':') == NULL) return (-1); if ((str = strdup(p)) == NULL) return (-1); /* XXX */ user = str; pwd = strchr(str, ':'); *pwd++ = '\0'; r = http_basic_auth(conn, hdr, user, pwd); free(str); return (r); } return (-1); } /***************************************************************************** * Helper functions for connecting to a server or proxy */ /* * Connect to the correct HTTP server or proxy. */ static conn_t * http_connect(struct url *URL, struct url *purl, const char *flags, int *cached) { struct url *curl; conn_t *conn; int af, verbose; #ifdef TCP_NOPUSH int val; #endif #ifdef INET6 af = AF_UNSPEC; #else af = AF_INET; #endif verbose = CHECK_FLAG('v'); if (CHECK_FLAG('4')) af = AF_INET; #ifdef INET6 else if (CHECK_FLAG('6')) af = AF_INET6; #endif curl = (purl != NULL) ? purl : URL; if ((conn = fetch_cache_get(curl, af)) != NULL) { *cached = 1; return (conn); } if ((conn = fetch_connect(curl, af, verbose)) == NULL) /* fetch_connect() has already set an error code */ return (NULL); if (strcasecmp(URL->scheme, SCHEME_HTTPS) == 0 && purl) { http_cmd(conn, "CONNECT %s:%d HTTP/1.1\r\n\r\n", URL->host, URL->port); if (http_get_reply(conn) != HTTP_OK) { fetch_close(conn); return (NULL); } http_get_reply(conn); } if (strcasecmp(URL->scheme, SCHEME_HTTPS) == 0 && fetch_ssl(conn, URL, verbose) == -1) { fetch_close(conn); /* grrr */ #ifdef EAUTH errno = EAUTH; #else errno = EPERM; #endif fetch_syserr(); return (NULL); } #ifdef TCP_NOPUSH val = 1; setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, sizeof(val)); #endif return (conn); } static struct url * http_get_proxy(struct url * url, const char *flags) { struct url *purl; char *p; if (flags != NULL && strchr(flags, 'd') != NULL) return (NULL); if (fetch_no_proxy_match(url->host)) return (NULL); if (((p = getenv("HTTP_PROXY")) || (p = getenv("http_proxy"))) && *p && (purl = fetchParseURL(p))) { if (!*purl->scheme) strcpy(purl->scheme, SCHEME_HTTP); if (!purl->port) purl->port = fetch_default_proxy_port(purl->scheme); if (strcasecmp(purl->scheme, SCHEME_HTTP) == 0) return (purl); fetchFreeURL(purl); } return (NULL); } static void set_if_modified_since(conn_t *conn, time_t last_modified) { static const char weekdays[] = "SunMonTueWedThuFriSat"; static const char months[] = "JanFebMarAprMayJunJulAugSepOctNovDec"; struct tm tm; char buf[80]; gmtime_r(&last_modified, &tm); snprintf(buf, sizeof(buf), "%.3s, %02d %.3s %4ld %02d:%02d:%02d GMT", weekdays + tm.tm_wday * 3, tm.tm_mday, months + tm.tm_mon * 3, (long)(tm.tm_year + 1900), tm.tm_hour, tm.tm_min, tm.tm_sec); http_cmd(conn, "If-Modified-Since: %s\r\n", buf); } /***************************************************************************** * Core */ /* * Send a request and process the reply * * XXX This function is way too long, the do..while loop should be split * XXX off into a separate function. */ fetchIO * http_request(struct url *URL, const char *op, struct url_stat *us, struct url *purl, const char *flags) { conn_t *conn = NULL; struct url *url, *new; int chunked, direct, if_modified_since, need_auth, noredirect; int keep_alive, verbose, cached; int e, i, n, val; off_t offset, clength, length, size; time_t mtime; const char *p; fetchIO *f; hdr_t h; char hbuf[URL_HOSTLEN + 7], *host; direct = CHECK_FLAG('d'); noredirect = CHECK_FLAG('A'); verbose = CHECK_FLAG('v'); if_modified_since = CHECK_FLAG('i'); keep_alive = 0; if (direct && purl) { fetchFreeURL(purl); purl = NULL; } /* try the provided URL first */ url = URL; /* if the A flag is set, we only get one try */ n = noredirect ? 1 : MAX_REDIRECT; i = 0; e = HTTP_PROTOCOL_ERROR; need_auth = 0; do { new = NULL; chunked = 0; offset = 0; clength = -1; length = -1; size = -1; mtime = 0; cached = 0; /* check port */ if (!url->port) url->port = fetch_default_port(url->scheme); /* were we redirected to an FTP URL? */ if (purl == NULL && strcmp(url->scheme, SCHEME_FTP) == 0) { if (strcmp(op, "GET") == 0) return (ftp_request(url, "RETR", NULL, us, purl, flags)); else if (strcmp(op, "HEAD") == 0) return (ftp_request(url, "STAT", NULL, us, purl, flags)); } /* connect to server or proxy */ if (conn != NULL) fetch_close(conn); if ((conn = http_connect(url, purl, flags, &cached)) == NULL) goto ouch; host = url->host; #ifdef INET6 if (strchr(url->host, ':')) { snprintf(hbuf, sizeof(hbuf), "[%s]", url->host); host = hbuf; } #endif if (url->port != fetch_default_port(url->scheme)) { if (host != hbuf) { strcpy(hbuf, host); host = hbuf; } snprintf(hbuf + strlen(hbuf), sizeof(hbuf) - strlen(hbuf), ":%d", url->port); } /* send request */ if (verbose) fetch_info("requesting %s://%s%s", url->scheme, host, url->doc); if (purl && strcasecmp(URL->scheme, SCHEME_HTTPS) != 0) { http_cmd(conn, "%s %s://%s%s HTTP/1.1\r\n", op, url->scheme, host, url->doc); } else { http_cmd(conn, "%s %s HTTP/1.1\r\n", op, url->doc); } if (if_modified_since && url->last_modified > 0) set_if_modified_since(conn, url->last_modified); /* virtual host */ http_cmd(conn, "Host: %s\r\n", host); /* proxy authorization */ if (purl) { if (*purl->user || *purl->pwd) http_basic_auth(conn, "Proxy-Authorization", purl->user, purl->pwd); else if ((p = getenv("HTTP_PROXY_AUTH")) != NULL && *p != '\0') http_authorize(conn, "Proxy-Authorization", p); } /* server authorization */ if (need_auth || *url->user || *url->pwd) { if (*url->user || *url->pwd) http_basic_auth(conn, "Authorization", url->user, url->pwd); else if ((p = getenv("HTTP_AUTH")) != NULL && *p != '\0') http_authorize(conn, "Authorization", p); else if (fetchAuthMethod && fetchAuthMethod(url) == 0) { http_basic_auth(conn, "Authorization", url->user, url->pwd); } else { http_seterr(HTTP_NEED_AUTH); goto ouch; } } /* other headers */ if ((p = getenv("HTTP_REFERER")) != NULL && *p != '\0') { if (strcasecmp(p, "auto") == 0) http_cmd(conn, "Referer: %s://%s%s\r\n", url->scheme, host, url->doc); else http_cmd(conn, "Referer: %s\r\n", p); } if ((p = getenv("HTTP_USER_AGENT")) != NULL) { /* no User-Agent if defined but empty */ if (*p != '\0') http_cmd(conn, "User-Agent: %s\r\n", p); } else { /* default User-Agent */ http_cmd(conn, "User-Agent: %s\r\n", _LIBFETCH_VER); } /* * Some servers returns 406 (Not Acceptable) if the Accept field is not * provided by the user agent, such example is http://alioth.debian.org. */ http_cmd(conn, "Accept: */*\r\n"); if (url->offset > 0) http_cmd(conn, "Range: bytes=%lld-\r\n", (long long)url->offset); http_cmd(conn, "\r\n"); /* * Force the queued request to be dispatched. Normally, one * would do this with shutdown(2) but squid proxies can be * configured to disallow such half-closed connections. To * be compatible with such configurations, fiddle with socket * options to force the pending data to be written. */ #ifdef TCP_NOPUSH val = 0; setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, sizeof(val)); #endif val = 1; setsockopt(conn->sd, IPPROTO_TCP, TCP_NODELAY, &val, sizeof(val)); /* get reply */ switch (http_get_reply(conn)) { case HTTP_OK: case HTTP_PARTIAL: case HTTP_NOT_MODIFIED: /* fine */ break; case HTTP_MOVED_PERM: case HTTP_MOVED_TEMP: case HTTP_SEE_OTHER: case HTTP_USE_PROXY: /* * Not so fine, but we still have to read the * headers to get the new location. */ break; case HTTP_NEED_AUTH: if (need_auth) { /* * We already sent out authorization code, * so there's nothing more we can do. */ http_seterr(conn->err); goto ouch; } /* try again, but send the password this time */ if (verbose) fetch_info("server requires authorization"); break; case HTTP_NEED_PROXY_AUTH: /* * If we're talking to a proxy, we already sent * our proxy authorization code, so there's * nothing more we can do. */ http_seterr(conn->err); goto ouch; case HTTP_BAD_RANGE: /* * This can happen if we ask for 0 bytes because * we already have the whole file. Consider this * a success for now, and check sizes later. */ break; case HTTP_PROTOCOL_ERROR: /* fall through */ case -1: --i; if (cached) continue; fetch_syserr(); goto ouch; default: http_seterr(conn->err); if (!verbose) goto ouch; /* fall through so we can get the full error message */ } /* get headers */ do { switch ((h = http_next_header(conn, &p))) { case hdr_syserror: fetch_syserr(); goto ouch; case hdr_error: http_seterr(HTTP_PROTOCOL_ERROR); goto ouch; case hdr_connection: /* XXX too weak? */ keep_alive = (strcasecmp(p, "keep-alive") == 0); break; case hdr_content_length: http_parse_length(p, &clength); break; case hdr_content_range: http_parse_range(p, &offset, &length, &size); break; case hdr_last_modified: http_parse_mtime(p, &mtime); break; case hdr_location: if (!HTTP_REDIRECT(conn->err)) break; if (new) free(new); if (verbose) fetch_info("%d redirect to %s", conn->err, p); if (*p == '/') /* absolute path */ new = fetchMakeURL(url->scheme, url->host, url->port, p, url->user, url->pwd); else new = fetchParseURL(p); if (new == NULL) { /* XXX should set an error code */ goto ouch; } if (!*new->user && !*new->pwd) { strcpy(new->user, url->user); strcpy(new->pwd, url->pwd); } new->offset = url->offset; new->length = url->length; break; case hdr_transfer_encoding: /* XXX weak test*/ chunked = (strcasecmp(p, "chunked") == 0); break; case hdr_www_authenticate: if (conn->err != HTTP_NEED_AUTH) break; /* if we were smarter, we'd check the method and realm */ break; case hdr_end: /* fall through */ case hdr_unknown: /* ignore */ break; } } while (h > hdr_end); /* we need to provide authentication */ if (conn->err == HTTP_NEED_AUTH) { e = conn->err; need_auth = 1; fetch_close(conn); conn = NULL; continue; } /* requested range not satisfiable */ if (conn->err == HTTP_BAD_RANGE) { if (url->offset == size && url->length == 0) { /* asked for 0 bytes; fake it */ offset = url->offset; conn->err = HTTP_OK; break; } else { http_seterr(conn->err); goto ouch; } } /* we have a hit or an error */ if (conn->err == HTTP_OK || conn->err == HTTP_PARTIAL || conn->err == HTTP_NOT_MODIFIED || HTTP_ERROR(conn->err)) break; /* all other cases: we got a redirect */ e = conn->err; need_auth = 0; fetch_close(conn); conn = NULL; if (!new) break; if (url != URL) fetchFreeURL(url); url = new; } while (++i < n); /* we failed, or ran out of retries */ if (conn == NULL) { http_seterr(e); goto ouch; } /* fill in stats */ if (us && size) { us->size = size; } /* check for inconsistencies */ if (clength != -1 && length != -1 && clength != length) { http_seterr(HTTP_PROTOCOL_ERROR); goto ouch; } if (clength == -1) clength = length; if (clength != -1) length = offset + clength; if (length != -1 && size != -1 && length != size) { http_seterr(HTTP_PROTOCOL_ERROR); goto ouch; } if (size == -1) size = length; /* fill in stats */ if (us) { us->size = size; us->atime = us->mtime = mtime; } /* too far? */ if (URL->offset > 0 && offset > URL->offset) { http_seterr(HTTP_PROTOCOL_ERROR); goto ouch; } /* report back real offset and size */ URL->offset = offset; URL->length = clength; if (clength == -1 && !chunked && conn->err != HTTP_NOT_MODIFIED) keep_alive = 0; if (conn->err == HTTP_NOT_MODIFIED) { http_seterr(HTTP_NOT_MODIFIED); if (keep_alive) { fetch_cache_put(conn, fetch_close); conn = NULL; } goto ouch; } /* wrap it up in a fetchIO */ if ((f = http_funopen(conn, chunked, keep_alive, clength)) == NULL) { fetch_syserr(); goto ouch; } if (url != URL) fetchFreeURL(url); if (purl) fetchFreeURL(purl); if (HTTP_ERROR(conn->err)) { if (keep_alive) { char buf[512]; do { } while (fetchIO_read(f, buf, sizeof(buf)) > 0); } fetchIO_close(f); f = NULL; } return (f); ouch: if (url != URL) fetchFreeURL(url); if (purl) fetchFreeURL(purl); if (conn != NULL) fetch_close(conn); return (NULL); } /***************************************************************************** * Entry points */ /* * Retrieve and stat a file by HTTP */ fetchIO * fetchXGetHTTP(struct url *URL, struct url_stat *us, const char *flags) { return (http_request(URL, "GET", us, http_get_proxy(URL, flags), flags)); } /* * Retrieve a file by HTTP */ fetchIO * fetchGetHTTP(struct url *URL, const char *flags) { return (fetchXGetHTTP(URL, NULL, flags)); } /* * Store a file by HTTP */ fetchIO * fetchPutHTTP(struct url *URL, const char *flags) { (void)URL; (void)flags; fprintf(stderr, "fetchPutHTTP(): not implemented\n"); return (NULL); } /* * Get an HTTP document's metadata */ int fetchStatHTTP(struct url *URL, struct url_stat *us, const char *flags) { fetchIO *f; f = http_request(URL, "HEAD", us, http_get_proxy(URL, flags), flags); if (f == NULL) return (-1); fetchIO_close(f); return (0); } enum http_states { ST_NONE, ST_LT, ST_LTA, ST_TAGA, ST_H, ST_R, ST_E, ST_F, ST_HREF, ST_HREFQ, ST_TAG, ST_TAGAX, ST_TAGAQ }; struct index_parser { struct url_list *ue; struct url *url; enum http_states state; }; static ssize_t parse_index(struct index_parser *parser, const char *buf, size_t len) { char *end_attr, p = *buf; switch (parser->state) { case ST_NONE: /* Plain text, not in markup */ if (p == '<') parser->state = ST_LT; return 1; case ST_LT: /* In tag -- "<" already found */ if (p == '>') parser->state = ST_NONE; else if (p == 'a' || p == 'A') parser->state = ST_LTA; else if (!isspace((unsigned char)p)) parser->state = ST_TAG; return 1; case ST_LTA: /* In tag -- "') parser->state = ST_NONE; else if (p == '"') parser->state = ST_TAGAQ; else if (isspace((unsigned char)p)) parser->state = ST_TAGA; else parser->state = ST_TAG; return 1; case ST_TAG: /* In tag, but not "') parser->state = ST_NONE; return 1; case ST_TAGA: /* In a-tag -- "') parser->state = ST_NONE; else if (p == '"') parser->state = ST_TAGAQ; else if (p == 'h' || p == 'H') parser->state = ST_H; else if (!isspace((unsigned char)p)) parser->state = ST_TAGAX; return 1; case ST_TAGAX: /* In unknown keyword in a-tag */ if (p == '>') parser->state = ST_NONE; else if (p == '"') parser->state = ST_TAGAQ; else if (isspace((unsigned char)p)) parser->state = ST_TAGA; return 1; case ST_TAGAQ: /* In a-tag, unknown argument for keys. */ if (p == '>') parser->state = ST_NONE; else if (p == '"') parser->state = ST_TAGA; return 1; case ST_H: /* In a-tag -- "') parser->state = ST_NONE; else if (p == '"') parser->state = ST_TAGAQ; else if (p == 'r' || p == 'R') parser->state = ST_R; else if (isspace((unsigned char)p)) parser->state = ST_TAGA; else parser->state = ST_TAGAX; return 1; case ST_R: /* In a-tag -- "') parser->state = ST_NONE; else if (p == '"') parser->state = ST_TAGAQ; else if (p == 'e' || p == 'E') parser->state = ST_E; else if (isspace((unsigned char)p)) parser->state = ST_TAGA; else parser->state = ST_TAGAX; return 1; case ST_E: /* In a-tag -- "') parser->state = ST_NONE; else if (p == '"') parser->state = ST_TAGAQ; else if (p == 'f' || p == 'F') parser->state = ST_F; else if (isspace((unsigned char)p)) parser->state = ST_TAGA; else parser->state = ST_TAGAX; return 1; case ST_F: /* In a-tag -- "') parser->state = ST_NONE; else if (p == '"') parser->state = ST_TAGAQ; else if (p == '=') parser->state = ST_HREF; else if (!isspace((unsigned char)p)) parser->state = ST_TAGAX; return 1; case ST_HREF: /* In a-tag -- "state = ST_HREFQ; else if (!isspace((unsigned char)p)) parser->state = ST_TAGA; return 1; case ST_HREFQ: /* In href of the a-tag */ end_attr = memchr(buf, '"', len); if (end_attr == NULL) return 0; *end_attr = '\0'; parser->state = ST_TAGA; if (fetch_add_entry(parser->ue, parser->url, buf, 1)) return -1; return end_attr + 1 - buf; } /* NOTREACHED */ abort(); } struct http_index_cache { struct http_index_cache *next; struct url *location; struct url_list ue; }; static struct http_index_cache *index_cache; /* * List a directory */ int fetchListHTTP(struct url_list *ue, struct url *url, const char *pattern, const char *flags) { fetchIO *f; char buf[2 * PATH_MAX]; size_t buf_len, sum_processed; ssize_t read_len, processed; struct index_parser state; struct http_index_cache *cache = NULL; int do_cache, ret; (void)pattern; do_cache = CHECK_FLAG('c'); if (do_cache) { for (cache = index_cache; cache != NULL; cache = cache->next) { if (strcmp(cache->location->scheme, url->scheme)) continue; if (strcmp(cache->location->user, url->user)) continue; if (strcmp(cache->location->pwd, url->pwd)) continue; if (strcmp(cache->location->host, url->host)) continue; if (cache->location->port != url->port) continue; if (strcmp(cache->location->doc, url->doc)) continue; return fetchAppendURLList(ue, &cache->ue); } cache = malloc(sizeof(*cache)); if (cache == NULL) return -1; fetchInitURLList(&cache->ue); cache->location = fetchCopyURL(url); } f = fetchGetHTTP(url, flags); if (f == NULL) { if (do_cache) { fetchFreeURLList(&cache->ue); fetchFreeURL(cache->location); free(cache); } return -1; } state.url = url; state.state = ST_NONE; if (do_cache) { state.ue = &cache->ue; } else { state.ue = ue; } buf_len = 0; while ((read_len = fetchIO_read(f, buf + buf_len, sizeof(buf) - buf_len)) > 0) { buf_len += read_len; sum_processed = 0; do { processed = parse_index(&state, buf + sum_processed, buf_len); if (processed == -1) break; buf_len -= processed; sum_processed += processed; } while (processed != 0 && buf_len > 0); if (processed == -1) { read_len = -1; break; } memmove(buf, buf + sum_processed, buf_len); } fetchIO_close(f); ret = read_len < 0 ? -1 : 0; if (do_cache) { if (ret == 0) { cache->next = index_cache; index_cache = cache; } if (fetchAppendURLList(ue, &cache->ue)) ret = -1; } return ret; }