diff options
Diffstat (limited to 'lib/libfetch/http.c')
| -rw-r--r-- | lib/libfetch/http.c | 1996 |
1 files changed, 1996 insertions, 0 deletions
diff --git a/lib/libfetch/http.c b/lib/libfetch/http.c new file mode 100644 index 0000000..b33d6f1 --- /dev/null +++ b/lib/libfetch/http.c @@ -0,0 +1,1996 @@ +/*- + * Copyright (c) 2000-2011 Dag-Erling Smørgrav + * 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. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +/* + * 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. + */ + +#include <sys/param.h> +#include <sys/socket.h> +#include <sys/time.h> + +#include <ctype.h> +#include <err.h> +#include <errno.h> +#include <locale.h> +#include <netdb.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> +#include <unistd.h> +#include <md5.h> + +#include <netinet/in.h> +#include <netinet/tcp.h> + +#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_TEMP_REDIRECT 307 +#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_SEE_OTHER) + +#define HTTP_ERROR(xyz) ((xyz) > 400 && (xyz) < 599) + + +/***************************************************************************** + * I/O functions for decoding chunked streams + */ + +struct httpio +{ + conn_t *conn; /* connection */ + int chunked; /* chunked 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 */ +#ifndef NDEBUG + size_t total; +#endif +}; + +/* + * 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'; + } + } + +#ifndef NDEBUG + if (fetchDebug) { + io->total += io->chunksize; + if (io->chunksize == 0) + fprintf(stderr, "%s(): end of last chunk\n", __func__); + else + fprintf(stderr, "%s(): new chunk: %lu (%lu)\n", + __func__, (unsigned long)io->chunksize, + (unsigned long)io->total); + } +#endif + + return (io->chunksize); +} + +/* + * Grow the input buffer to at least len bytes + */ +static inline 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->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); + } + 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; + 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->chunksize == 0) { + char endl[2]; + + if (fetch_read(io->conn, endl, 2) != 2 || + endl[0] != '\r' || endl[1] != '\n') + return (-1); + } + + io->bufpos = 0; + + return (io->buflen); +} + +/* + * Read function + */ +static int +http_readfn(void *v, char *buf, int len) +{ + struct httpio *io = (struct httpio *)v; + int 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; + l = io->buflen - io->bufpos; + if (len < l) + l = len; + memcpy(buf + pos, io->buf + io->bufpos, l); + io->bufpos += l; + } + + if (!pos && io->error) + return (-1); + return (pos); +} + +/* + * Write function + */ +static int +http_writefn(void *v, const char *buf, int len) +{ + struct httpio *io = (struct httpio *)v; + + return (fetch_write(io->conn, buf, len)); +} + +/* + * Close function + */ +static int +http_closefn(void *v) +{ + struct httpio *io = (struct httpio *)v; + int r; + + r = fetch_close(io->conn); + if (io->buf) + free(io->buf); + free(io); + return (r); +} + +/* + * Wrap a file descriptor up + */ +static FILE * +http_funopen(conn_t *conn, int chunked) +{ + struct httpio *io; + FILE *f; + + if ((io = calloc(1, sizeof(*io))) == NULL) { + fetch_syserr(); + return (NULL); + } + io->conn = conn; + io->chunked = chunked; + f = funopen(io, http_readfn, http_writefn, NULL, 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_content_length, + hdr_content_range, + hdr_last_modified, + hdr_location, + hdr_transfer_encoding, + hdr_www_authenticate, + hdr_proxy_authenticate, +} hdr_t; + +/* Names of interesting headers */ +static struct { + hdr_t num; + const char *name; +} hdr_names[] = { + { 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_proxy_authenticate, "Proxy-Authenticate" }, + { hdr_unknown, NULL }, +}; + +/* + * Send a formatted line; optionally echo to terminal + */ +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_putln(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. We + * need to read one line ahead for checking for a continuation line + * belonging to the current header (continuation lines start with + * white space). + * + * We get called with a fresh line already in the conn buffer, either + * from the previous http_next_header() invocation, or, the first + * time, from a fetch_getln() performed by our caller. + * + * This stops when we encounter an empty line (we dont read beyond the header + * area). + * + * Note that the "headerbuf" is just a place to return the result. Its + * contents are not used for the next call. This means that no cleanup + * is needed when ie doing another connection, just call the cleanup when + * fully done to deallocate memory. + */ + +/* Limit the max number of continuation lines to some reasonable value */ +#define HTTP_MAX_CONT_LINES 10 + +/* Place into which to build a header from one or several lines */ +typedef struct { + char *buf; /* buffer */ + size_t bufsize; /* buffer size */ + size_t buflen; /* length of buffer contents */ +} http_headerbuf_t; + +static void +init_http_headerbuf(http_headerbuf_t *buf) +{ + buf->buf = NULL; + buf->bufsize = 0; + buf->buflen = 0; +} + +static void +clean_http_headerbuf(http_headerbuf_t *buf) +{ + if (buf->buf) + free(buf->buf); + init_http_headerbuf(buf); +} + +/* Remove whitespace at the end of the buffer */ +static void +http_conn_trimright(conn_t *conn) +{ + while (conn->buflen && + isspace((unsigned char)conn->buf[conn->buflen - 1])) + conn->buflen--; + conn->buf[conn->buflen] = '\0'; +} + +static hdr_t +http_next_header(conn_t *conn, http_headerbuf_t *hbuf, const char **p) +{ + unsigned int i, len; + + /* + * Have to do the stripping here because of the first line. So + * it's done twice for the subsequent lines. No big deal + */ + http_conn_trimright(conn); + if (conn->buflen == 0) + return (hdr_end); + + /* Copy the line to the headerbuf */ + if (hbuf->bufsize < conn->buflen + 1) { + if ((hbuf->buf = realloc(hbuf->buf, conn->buflen + 1)) == NULL) + return (hdr_syserror); + hbuf->bufsize = conn->buflen + 1; + } + strcpy(hbuf->buf, conn->buf); + hbuf->buflen = conn->buflen; + + /* + * Fetch possible continuation lines. Stop at 1st non-continuation + * and leave it in the conn buffer + */ + for (i = 0; i < HTTP_MAX_CONT_LINES; i++) { + if (fetch_getln(conn) == -1) + return (hdr_syserror); + + /* + * Note: we carry on the idea from the previous version + * that a pure whitespace line is equivalent to an empty + * one (so it's not continuation and will be handled when + * we are called next) + */ + http_conn_trimright(conn); + if (conn->buf[0] != ' ' && conn->buf[0] != "\t"[0]) + break; + + /* Got a continuation line. Concatenate to previous */ + len = hbuf->buflen + conn->buflen; + if (hbuf->bufsize < len + 1) { + len *= 2; + if ((hbuf->buf = realloc(hbuf->buf, len + 1)) == NULL) + return (hdr_syserror); + hbuf->bufsize = len + 1; + } + strcpy(hbuf->buf + hbuf->buflen, conn->buf); + hbuf->buflen += conn->buflen; + } + + /* + * 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, hbuf->buf)) != NULL) + return (hdr_names[i].num); + + return (hdr_unknown); +} + +/************************** + * [Proxy-]Authenticate header parsing + */ + +/* + * Read doublequote-delimited string into output buffer obuf (allocated + * by caller, whose responsibility it is to ensure that it's big enough) + * cp points to the first char after the initial '"' + * Handles \ quoting + * Returns pointer to the first char after the terminating double quote, or + * NULL for error. + */ +static const char * +http_parse_headerstring(const char *cp, char *obuf) +{ + for (;;) { + switch (*cp) { + case 0: /* Unterminated string */ + *obuf = 0; + return (NULL); + case '"': /* Ending quote */ + *obuf = 0; + return (++cp); + case '\\': + if (*++cp == 0) { + *obuf = 0; + return (NULL); + } + /* FALLTHROUGH */ + default: + *obuf++ = *cp++; + } + } +} + +/* Http auth challenge schemes */ +typedef enum {HTTPAS_UNKNOWN, HTTPAS_BASIC,HTTPAS_DIGEST} http_auth_schemes_t; + +/* Data holder for a Basic or Digest challenge. */ +typedef struct { + http_auth_schemes_t scheme; + char *realm; + char *qop; + char *nonce; + char *opaque; + char *algo; + int stale; + int nc; /* Nonce count */ +} http_auth_challenge_t; + +static void +init_http_auth_challenge(http_auth_challenge_t *b) +{ + b->scheme = HTTPAS_UNKNOWN; + b->realm = b->qop = b->nonce = b->opaque = b->algo = NULL; + b->stale = b->nc = 0; +} + +static void +clean_http_auth_challenge(http_auth_challenge_t *b) +{ + if (b->realm) + free(b->realm); + if (b->qop) + free(b->qop); + if (b->nonce) + free(b->nonce); + if (b->opaque) + free(b->opaque); + if (b->algo) + free(b->algo); + init_http_auth_challenge(b); +} + +/* Data holder for an array of challenges offered in an http response. */ +#define MAX_CHALLENGES 10 +typedef struct { + http_auth_challenge_t *challenges[MAX_CHALLENGES]; + int count; /* Number of parsed challenges in the array */ + int valid; /* We did parse an authenticate header */ +} http_auth_challenges_t; + +static void +init_http_auth_challenges(http_auth_challenges_t *cs) +{ + int i; + for (i = 0; i < MAX_CHALLENGES; i++) + cs->challenges[i] = NULL; + cs->count = cs->valid = 0; +} + +static void +clean_http_auth_challenges(http_auth_challenges_t *cs) +{ + int i; + /* We rely on non-zero pointers being allocated, not on the count */ + for (i = 0; i < MAX_CHALLENGES; i++) { + if (cs->challenges[i] != NULL) { + clean_http_auth_challenge(cs->challenges[i]); + free(cs->challenges[i]); + } + } + init_http_auth_challenges(cs); +} + +/* + * Enumeration for lexical elements. Separators will be returned as their own + * ascii value + */ +typedef enum {HTTPHL_WORD=256, HTTPHL_STRING=257, HTTPHL_END=258, + HTTPHL_ERROR = 259} http_header_lex_t; + +/* + * Determine what kind of token comes next and return possible value + * in buf, which is supposed to have been allocated big enough by + * caller. Advance input pointer and return element type. + */ +static int +http_header_lex(const char **cpp, char *buf) +{ + size_t l; + /* Eat initial whitespace */ + *cpp += strspn(*cpp, " \t"); + if (**cpp == 0) + return (HTTPHL_END); + + /* Separator ? */ + if (**cpp == ',' || **cpp == '=') + return (*((*cpp)++)); + + /* String ? */ + if (**cpp == '"') { + *cpp = http_parse_headerstring(++*cpp, buf); + if (*cpp == NULL) + return (HTTPHL_ERROR); + return (HTTPHL_STRING); + } + + /* Read other token, until separator or whitespace */ + l = strcspn(*cpp, " \t,="); + memcpy(buf, *cpp, l); + buf[l] = 0; + *cpp += l; + return (HTTPHL_WORD); +} + +/* + * Read challenges from http xxx-authenticate header and accumulate them + * in the challenges list structure. + * + * Headers with multiple challenges are specified by rfc2617, but + * servers (ie: squid) often send them in separate headers instead, + * which in turn is forbidden by the http spec (multiple headers with + * the same name are only allowed for pure comma-separated lists, see + * rfc2616 sec 4.2). + * + * We support both approaches anyway + */ +static int +http_parse_authenticate(const char *cp, http_auth_challenges_t *cs) +{ + int ret = -1; + http_header_lex_t lex; + char *key = malloc(strlen(cp) + 1); + char *value = malloc(strlen(cp) + 1); + char *buf = malloc(strlen(cp) + 1); + + if (key == NULL || value == NULL || buf == NULL) { + fetch_syserr(); + goto out; + } + + /* In any case we've seen the header and we set the valid bit */ + cs->valid = 1; + + /* Need word first */ + lex = http_header_lex(&cp, key); + if (lex != HTTPHL_WORD) + goto out; + + /* Loop on challenges */ + for (; cs->count < MAX_CHALLENGES; cs->count++) { + cs->challenges[cs->count] = + malloc(sizeof(http_auth_challenge_t)); + if (cs->challenges[cs->count] == NULL) { + fetch_syserr(); + goto out; + } + init_http_auth_challenge(cs->challenges[cs->count]); + if (!strcasecmp(key, "basic")) { + cs->challenges[cs->count]->scheme = HTTPAS_BASIC; + } else if (!strcasecmp(key, "digest")) { + cs->challenges[cs->count]->scheme = HTTPAS_DIGEST; + } else { + cs->challenges[cs->count]->scheme = HTTPAS_UNKNOWN; + /* + * Continue parsing as basic or digest may + * follow, and the syntax is the same for + * all. We'll just ignore this one when + * looking at the list + */ + } + + /* Loop on attributes */ + for (;;) { + /* Key */ + lex = http_header_lex(&cp, key); + if (lex != HTTPHL_WORD) + goto out; + + /* Equal sign */ + lex = http_header_lex(&cp, buf); + if (lex != '=') + goto out; + + /* Value */ + lex = http_header_lex(&cp, value); + if (lex != HTTPHL_WORD && lex != HTTPHL_STRING) + goto out; + + if (!strcasecmp(key, "realm")) + cs->challenges[cs->count]->realm = + strdup(value); + else if (!strcasecmp(key, "qop")) + cs->challenges[cs->count]->qop = + strdup(value); + else if (!strcasecmp(key, "nonce")) + cs->challenges[cs->count]->nonce = + strdup(value); + else if (!strcasecmp(key, "opaque")) + cs->challenges[cs->count]->opaque = + strdup(value); + else if (!strcasecmp(key, "algorithm")) + cs->challenges[cs->count]->algo = + strdup(value); + else if (!strcasecmp(key, "stale")) + cs->challenges[cs->count]->stale = + strcasecmp(value, "no"); + /* Else ignore unknown attributes */ + + /* Comma or Next challenge or End */ + lex = http_header_lex(&cp, key); + /* + * If we get a word here, this is the beginning of the + * next challenge. Break the attributes loop + */ + if (lex == HTTPHL_WORD) + break; + + if (lex == HTTPHL_END) { + /* End while looking for ',' is normal exit */ + cs->count++; + ret = 0; + goto out; + } + /* Anything else is an error */ + if (lex != ',') + goto out; + + } /* End attributes loop */ + } /* End challenge loop */ + + /* + * Challenges max count exceeded. This really can't happen + * with normal data, something's fishy -> error + */ + +out: + if (key) + free(key); + if (value) + free(value); + if (buf) + free(buf); + return (ret); +} + + +/* + * 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)); + setlocale(LC_TIME, "C"); + r = strptime(p, "%a, %d %b %Y %H:%M:%S GMT", &tm); + /* XXX should add support for date-2 and date-3 */ + setlocale(LC_TIME, locale); + if (r == NULL) + return (-1); + DEBUG(fprintf(stderr, "last modified: [%04d-%02d-%02d " + "%02d:%02d:%02d]\n", + tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, + tm.tm_hour, tm.tm_min, tm.tm_sec)); + *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); + DEBUG(fprintf(stderr, "content length: [%lld]\n", + (long long)len)); + *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) { + DEBUG(fprintf(stderr, "content range: [*/%lld]\n", + (long long)len)); + *length = 0; + } else { + DEBUG(fprintf(stderr, "content range: [%lld-%lld/%lld]\n", + (long long)first, (long long)last, (long long)len)); + *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); +} + + +/* + * Extract authorization parameters from environment value. + * The value is like scheme:realm:user:pass + */ +typedef struct { + char *scheme; + char *realm; + char *user; + char *password; +} http_auth_params_t; + +static void +init_http_auth_params(http_auth_params_t *s) +{ + s->scheme = s->realm = s->user = s->password = 0; +} + +static void +clean_http_auth_params(http_auth_params_t *s) +{ + if (s->scheme) + free(s->scheme); + if (s->realm) + free(s->realm); + if (s->user) + free(s->user); + if (s->password) + free(s->password); + init_http_auth_params(s); +} + +static int +http_authfromenv(const char *p, http_auth_params_t *parms) +{ + int ret = -1; + char *v, *ve; + char *str = strdup(p); + + if (str == NULL) { + fetch_syserr(); + return (-1); + } + v = str; + + if ((ve = strchr(v, ':')) == NULL) + goto out; + + *ve = 0; + if ((parms->scheme = strdup(v)) == NULL) { + fetch_syserr(); + goto out; + } + v = ve + 1; + + if ((ve = strchr(v, ':')) == NULL) + goto out; + + *ve = 0; + if ((parms->realm = strdup(v)) == NULL) { + fetch_syserr(); + goto out; + } + v = ve + 1; + + if ((ve = strchr(v, ':')) == NULL) + goto out; + + *ve = 0; + if ((parms->user = strdup(v)) == NULL) { + fetch_syserr(); + goto out; + } + v = ve + 1; + + + if ((parms->password = strdup(v)) == NULL) { + fetch_syserr(); + goto out; + } + ret = 0; +out: + if (ret == -1) + clean_http_auth_params(parms); + if (str) + free(str); + return (ret); +} + + +/* + * Digest response: the code to compute the digest is taken from the + * sample implementation in RFC2616 + */ +#define IN const +#define OUT + +#define HASHLEN 16 +typedef char HASH[HASHLEN]; +#define HASHHEXLEN 32 +typedef char HASHHEX[HASHHEXLEN+1]; + +static const char *hexchars = "0123456789abcdef"; +static void +CvtHex(IN HASH Bin, OUT HASHHEX Hex) +{ + unsigned short i; + unsigned char j; + + for (i = 0; i < HASHLEN; i++) { + j = (Bin[i] >> 4) & 0xf; + Hex[i*2] = hexchars[j]; + j = Bin[i] & 0xf; + Hex[i*2+1] = hexchars[j]; + }; + Hex[HASHHEXLEN] = '\0'; +}; + +/* calculate H(A1) as per spec */ +static void +DigestCalcHA1( + IN char * pszAlg, + IN char * pszUserName, + IN char * pszRealm, + IN char * pszPassword, + IN char * pszNonce, + IN char * pszCNonce, + OUT HASHHEX SessionKey + ) +{ + MD5_CTX Md5Ctx; + HASH HA1; + + MD5Init(&Md5Ctx); + MD5Update(&Md5Ctx, pszUserName, strlen(pszUserName)); + MD5Update(&Md5Ctx, ":", 1); + MD5Update(&Md5Ctx, pszRealm, strlen(pszRealm)); + MD5Update(&Md5Ctx, ":", 1); + MD5Update(&Md5Ctx, pszPassword, strlen(pszPassword)); + MD5Final(HA1, &Md5Ctx); + if (strcasecmp(pszAlg, "md5-sess") == 0) { + + MD5Init(&Md5Ctx); + MD5Update(&Md5Ctx, HA1, HASHLEN); + MD5Update(&Md5Ctx, ":", 1); + MD5Update(&Md5Ctx, pszNonce, strlen(pszNonce)); + MD5Update(&Md5Ctx, ":", 1); + MD5Update(&Md5Ctx, pszCNonce, strlen(pszCNonce)); + MD5Final(HA1, &Md5Ctx); + }; + CvtHex(HA1, SessionKey); +} + +/* calculate request-digest/response-digest as per HTTP Digest spec */ +static void +DigestCalcResponse( + IN HASHHEX HA1, /* H(A1) */ + IN char * pszNonce, /* nonce from server */ + IN char * pszNonceCount, /* 8 hex digits */ + IN char * pszCNonce, /* client nonce */ + IN char * pszQop, /* qop-value: "", "auth", "auth-int" */ + IN char * pszMethod, /* method from the request */ + IN char * pszDigestUri, /* requested URL */ + IN HASHHEX HEntity, /* H(entity body) if qop="auth-int" */ + OUT HASHHEX Response /* request-digest or response-digest */ + ) +{ +/* DEBUG(fprintf(stderr, + "Calc: HA1[%s] Nonce[%s] qop[%s] method[%s] URI[%s]\n", + HA1, pszNonce, pszQop, pszMethod, pszDigestUri));*/ + MD5_CTX Md5Ctx; + HASH HA2; + HASH RespHash; + HASHHEX HA2Hex; + + // calculate H(A2) + MD5Init(&Md5Ctx); + MD5Update(&Md5Ctx, pszMethod, strlen(pszMethod)); + MD5Update(&Md5Ctx, ":", 1); + MD5Update(&Md5Ctx, pszDigestUri, strlen(pszDigestUri)); + if (strcasecmp(pszQop, "auth-int") == 0) { + MD5Update(&Md5Ctx, ":", 1); + MD5Update(&Md5Ctx, HEntity, HASHHEXLEN); + }; + MD5Final(HA2, &Md5Ctx); + CvtHex(HA2, HA2Hex); + + // calculate response + MD5Init(&Md5Ctx); + MD5Update(&Md5Ctx, HA1, HASHHEXLEN); + MD5Update(&Md5Ctx, ":", 1); + MD5Update(&Md5Ctx, pszNonce, strlen(pszNonce)); + MD5Update(&Md5Ctx, ":", 1); + if (*pszQop) { + MD5Update(&Md5Ctx, pszNonceCount, strlen(pszNonceCount)); + MD5Update(&Md5Ctx, ":", 1); + MD5Update(&Md5Ctx, pszCNonce, strlen(pszCNonce)); + MD5Update(&Md5Ctx, ":", 1); + MD5Update(&Md5Ctx, pszQop, strlen(pszQop)); + MD5Update(&Md5Ctx, ":", 1); + }; + MD5Update(&Md5Ctx, HA2Hex, HASHHEXLEN); + MD5Final(RespHash, &Md5Ctx); + CvtHex(RespHash, Response); +} + +/* + * Generate/Send a Digest authorization header + * This looks like: [Proxy-]Authorization: credentials + * + * credentials = "Digest" digest-response + * digest-response = 1#( username | realm | nonce | digest-uri + * | response | [ algorithm ] | [cnonce] | + * [opaque] | [message-qop] | + * [nonce-count] | [auth-param] ) + * username = "username" "=" username-value + * username-value = quoted-string + * digest-uri = "uri" "=" digest-uri-value + * digest-uri-value = request-uri ; As specified by HTTP/1.1 + * message-qop = "qop" "=" qop-value + * cnonce = "cnonce" "=" cnonce-value + * cnonce-value = nonce-value + * nonce-count = "nc" "=" nc-value + * nc-value = 8LHEX + * response = "response" "=" request-digest + * request-digest = <"> 32LHEX <"> + */ +static int +http_digest_auth(conn_t *conn, const char *hdr, http_auth_challenge_t *c, + http_auth_params_t *parms, struct url *url) +{ + int r; + char noncecount[10]; + char cnonce[40]; + char *options = 0; + + if (!c->realm || !c->nonce) { + DEBUG(fprintf(stderr, "realm/nonce not set in challenge\n")); + return(-1); + } + if (!c->algo) + c->algo = strdup(""); + + if (asprintf(&options, "%s%s%s%s", + *c->algo? ",algorithm=" : "", c->algo, + c->opaque? ",opaque=" : "", c->opaque?c->opaque:"")== -1) + return (-1); + + if (!c->qop) { + c->qop = strdup(""); + *noncecount = 0; + *cnonce = 0; + } else { + c->nc++; + sprintf(noncecount, "%08x", c->nc); + /* We don't try very hard with the cnonce ... */ + sprintf(cnonce, "%x%lx", getpid(), (unsigned long)time(0)); + } + + HASHHEX HA1; + DigestCalcHA1(c->algo, parms->user, c->realm, + parms->password, c->nonce, cnonce, HA1); + DEBUG(fprintf(stderr, "HA1: [%s]\n", HA1)); + HASHHEX digest; + DigestCalcResponse(HA1, c->nonce, noncecount, cnonce, c->qop, + "GET", url->doc, "", digest); + + if (c->qop[0]) { + r = http_cmd(conn, "%s: Digest username=\"%s\",realm=\"%s\"," + "nonce=\"%s\",uri=\"%s\",response=\"%s\"," + "qop=\"auth\", cnonce=\"%s\", nc=%s%s", + hdr, parms->user, c->realm, + c->nonce, url->doc, digest, + cnonce, noncecount, options); + } else { + r = http_cmd(conn, "%s: Digest username=\"%s\",realm=\"%s\"," + "nonce=\"%s\",uri=\"%s\",response=\"%s\"%s", + hdr, parms->user, c->realm, + c->nonce, url->doc, digest, options); + } + if (options) + free(options); + return (r); +} + +/* + * 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; + + DEBUG(fprintf(stderr, "basic: usr: [%s]\n", usr)); + DEBUG(fprintf(stderr, "basic: pwd: [%s]\n", pwd)); + 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", hdr, auth); + free(auth); + return (r); +} + +/* + * Chose the challenge to answer and call the appropriate routine to + * produce the header. + */ +static int +http_authorize(conn_t *conn, const char *hdr, http_auth_challenges_t *cs, + http_auth_params_t *parms, struct url *url) +{ + http_auth_challenge_t *basic = NULL; + http_auth_challenge_t *digest = NULL; + int i; + + /* If user or pass are null we're not happy */ + if (!parms->user || !parms->password) { + DEBUG(fprintf(stderr, "NULL usr or pass\n")); + return (-1); + } + + /* Look for a Digest and a Basic challenge */ + for (i = 0; i < cs->count; i++) { + if (cs->challenges[i]->scheme == HTTPAS_BASIC) + basic = cs->challenges[i]; + if (cs->challenges[i]->scheme == HTTPAS_DIGEST) + digest = cs->challenges[i]; + } + + /* Error if "Digest" was specified and there is no Digest challenge */ + if (!digest && (parms->scheme && + !strcasecmp(parms->scheme, "digest"))) { + DEBUG(fprintf(stderr, + "Digest auth in env, not supported by peer\n")); + return (-1); + } + /* + * If "basic" was specified in the environment, or there is no Digest + * challenge, do the basic thing. Don't need a challenge for this, + * so no need to check basic!=NULL + */ + if (!digest || (parms->scheme && !strcasecmp(parms->scheme,"basic"))) + return (http_basic_auth(conn,hdr,parms->user,parms->password)); + + /* Else, prefer digest. We just checked that it's not NULL */ + return (http_digest_auth(conn, hdr, digest, parms, url)); +} + +/***************************************************************************** + * 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) +{ + conn_t *conn; + int verbose; + int af, val; + +#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 + + if (purl && strcasecmp(URL->scheme, SCHEME_HTTPS) != 0) { + URL = purl; + } else if (strcasecmp(URL->scheme, SCHEME_FTP) == 0) { + /* can't talk http to an ftp server */ + /* XXX should set an error code */ + return (NULL); + } + + if ((conn = fetch_connect(URL->host, URL->port, af, verbose)) == NULL) + /* fetch_connect() has already set an error code */ + return (NULL); + if (strcasecmp(URL->scheme, SCHEME_HTTPS) == 0 && + fetch_ssl(conn, verbose) == -1) { + fetch_close(conn); + /* grrr */ + errno = EAUTH; + fetch_syserr(); + return (NULL); + } + + val = 1; + setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, sizeof(val)); + + 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 +http_print_html(FILE *out, FILE *in) +{ + size_t len; + char *line, *p, *q; + int comment, tag; + + comment = tag = 0; + while ((line = fgetln(in, &len)) != NULL) { + while (len && isspace((unsigned char)line[len - 1])) + --len; + for (p = q = line; q < line + len; ++q) { + if (comment && *q == '-') { + if (q + 2 < line + len && + strcmp(q, "-->") == 0) { + tag = comment = 0; + q += 2; + } + } else if (tag && !comment && *q == '>') { + p = q + 1; + tag = 0; + } else if (!tag && *q == '<') { + if (q > p) + fwrite(p, q - p, 1, out); + tag = 1; + if (q + 3 < line + len && + strcmp(q, "<!--") == 0) { + comment = 1; + q += 3; + } + } + } + if (!tag && q > p) + fwrite(p, q - p, 1, out); + fputc('\n', out); + } +} + + +/***************************************************************************** + * 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. + */ +FILE * +http_request(struct url *URL, const char *op, struct url_stat *us, + struct url *purl, const char *flags) +{ + char timebuf[80]; + char hbuf[MAXHOSTNAMELEN + 7], *host; + conn_t *conn; + struct url *url, *new; + int chunked, direct, ims, noredirect, verbose; + int e, i, n, val; + off_t offset, clength, length, size; + time_t mtime; + const char *p; + FILE *f; + hdr_t h; + struct tm *timestruct; + http_headerbuf_t headerbuf; + http_auth_challenges_t server_challenges; + http_auth_challenges_t proxy_challenges; + + /* The following calls don't allocate anything */ + init_http_headerbuf(&headerbuf); + init_http_auth_challenges(&server_challenges); + init_http_auth_challenges(&proxy_challenges); + + direct = CHECK_FLAG('d'); + noredirect = CHECK_FLAG('A'); + verbose = CHECK_FLAG('v'); + ims = CHECK_FLAG('i'); + + 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; + do { + new = NULL; + chunked = 0; + offset = 0; + clength = -1; + length = -1; + size = -1; + mtime = 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", us, purl, flags)); + else if (strcmp(op, "HEAD") == 0) + return (ftp_request(url, "STAT", us, purl, flags)); + } + + /* connect to server or proxy */ + if ((conn = http_connect(url, purl, flags)) == 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) { + http_cmd(conn, "%s %s://%s%s HTTP/1.1", + op, url->scheme, host, url->doc); + } else { + http_cmd(conn, "%s %s HTTP/1.1", + op, url->doc); + } + + if (ims && url->ims_time) { + timestruct = gmtime((time_t *)&url->ims_time); + (void)strftime(timebuf, 80, "%a, %d %b %Y %T GMT", + timestruct); + if (verbose) + fetch_info("If-Modified-Since: %s", timebuf); + http_cmd(conn, "If-Modified-Since: %s", timebuf); + } + /* virtual host */ + http_cmd(conn, "Host: %s", host); + + /* + * Proxy authorization: we only send auth after we received + * a 407 error. We do not first try basic anyway (changed + * when support was added for digest-auth) + */ + if (purl && proxy_challenges.valid) { + http_auth_params_t aparams; + init_http_auth_params(&aparams); + if (*purl->user || *purl->pwd) { + aparams.user = purl->user ? + strdup(purl->user) : strdup(""); + aparams.password = purl->pwd? + strdup(purl->pwd) : strdup(""); + } else if ((p = getenv("HTTP_PROXY_AUTH")) != NULL && + *p != '\0') { + if (http_authfromenv(p, &aparams) < 0) { + http_seterr(HTTP_NEED_PROXY_AUTH); + goto ouch; + } + } + http_authorize(conn, "Proxy-Authorization", + &proxy_challenges, &aparams, url); + clean_http_auth_params(&aparams); + } + + /* + * Server authorization: we never send "a priori" + * Basic auth, which used to be done if user/pass were + * set in the url. This would be weird because we'd send the + * password in the clear even if Digest is finally to be + * used (it would have made more sense for the + * pre-digest version to do this when Basic was specified + * in the environment) + */ + if (server_challenges.valid) { + http_auth_params_t aparams; + init_http_auth_params(&aparams); + if (*url->user || *url->pwd) { + aparams.user = url->user ? + strdup(url->user) : strdup(""); + aparams.password = url->pwd ? + strdup(url->pwd) : strdup(""); + } else if ((p = getenv("HTTP_AUTH")) != NULL && + *p != '\0') { + if (http_authfromenv(p, &aparams) < 0) { + http_seterr(HTTP_NEED_AUTH); + goto ouch; + } + } else if (fetchAuthMethod && + fetchAuthMethod(url) == 0) { + aparams.user = url->user ? + strdup(url->user) : strdup(""); + aparams.password = url->pwd ? + strdup(url->pwd) : strdup(""); + } else { + http_seterr(HTTP_NEED_AUTH); + goto ouch; + } + http_authorize(conn, "Authorization", + &server_challenges, &aparams, url); + clean_http_auth_params(&aparams); + } + + /* other headers */ + if ((p = getenv("HTTP_REFERER")) != NULL && *p != '\0') { + if (strcasecmp(p, "auto") == 0) + http_cmd(conn, "Referer: %s://%s%s", + url->scheme, host, url->doc); + else + http_cmd(conn, "Referer: %s", p); + } + if ((p = getenv("HTTP_USER_AGENT")) != NULL && *p != '\0') + http_cmd(conn, "User-Agent: %s", p); + else + http_cmd(conn, "User-Agent: %s " _LIBFETCH_VER, getprogname()); + if (url->offset > 0) + http_cmd(conn, "Range: bytes=%lld-", (long long)url->offset); + http_cmd(conn, "Connection: close"); + http_cmd(conn, ""); + + /* + * 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. + */ + val = 0; + setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, + sizeof(val)); + 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: + /* + * Not so fine, but we still have to read the + * headers to get the new location. + */ + break; + case HTTP_NEED_AUTH: + if (server_challenges.valid) { + /* + * 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 (proxy_challenges.valid) { + /* + * We already sent our proxy + * 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("proxy requires authorization"); + break; + 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: + 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. http_next_header expects one line readahead */ + if (fetch_getln(conn) == -1) { + fetch_syserr(); + goto ouch; + } + do { + switch ((h = http_next_header(conn, &headerbuf, &p))) { + case hdr_syserror: + fetch_syserr(); + goto ouch; + case hdr_error: + http_seterr(HTTP_PROTOCOL_ERROR); + goto ouch; + 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 */ + DEBUG(fprintf(stderr, "failed to parse new URL\n")); + 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 (http_parse_authenticate(p, &server_challenges) == 0) + ++n; + break; + case hdr_proxy_authenticate: + if (conn->err != HTTP_NEED_PROXY_AUTH) + break; + if (http_parse_authenticate(p, &proxy_challenges) == 0) + ++n; + 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 || + conn->err == HTTP_NEED_PROXY_AUTH) { + e = conn->err; + if ((conn->err == HTTP_NEED_AUTH && + !server_challenges.valid) || + (conn->err == HTTP_NEED_PROXY_AUTH && + !proxy_challenges.valid)) { + /* 401/7 but no www/proxy-authenticate ?? */ + DEBUG(fprintf(stderr, "401/7 and no auth header\n")); + goto ouch; + } + 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; + clength = -1; + 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_NOT_MODIFIED + || conn->err == HTTP_PARTIAL + || HTTP_ERROR(conn->err)) + break; + + /* all other cases: we got a redirect */ + e = conn->err; + clean_http_auth_challenges(&server_challenges); + fetch_close(conn); + conn = NULL; + if (!new) { + DEBUG(fprintf(stderr, "redirect with no new location\n")); + 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; + } + + DEBUG(fprintf(stderr, "offset %lld, length %lld," + " size %lld, clength %lld\n", + (long long)offset, (long long)length, + (long long)size, (long long)clength)); + + if (conn->err == HTTP_NOT_MODIFIED) { + http_seterr(HTTP_NOT_MODIFIED); + return (NULL); + } + + /* 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; + + /* wrap it up in a FILE */ + if ((f = http_funopen(conn, chunked)) == NULL) { + fetch_syserr(); + goto ouch; + } + + if (url != URL) + fetchFreeURL(url); + if (purl) + fetchFreeURL(purl); + + if (HTTP_ERROR(conn->err)) { + http_print_html(stderr, f); + fclose(f); + f = NULL; + } + clean_http_headerbuf(&headerbuf); + clean_http_auth_challenges(&server_challenges); + clean_http_auth_challenges(&proxy_challenges); + return (f); + +ouch: + if (url != URL) + fetchFreeURL(url); + if (purl) + fetchFreeURL(purl); + if (conn != NULL) + fetch_close(conn); + clean_http_headerbuf(&headerbuf); + clean_http_auth_challenges(&server_challenges); + clean_http_auth_challenges(&proxy_challenges); + return (NULL); +} + + +/***************************************************************************** + * Entry points + */ + +/* + * Retrieve and stat a file by HTTP + */ +FILE * +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 + */ +FILE * +fetchGetHTTP(struct url *URL, const char *flags) +{ + return (fetchXGetHTTP(URL, NULL, flags)); +} + +/* + * Store a file by HTTP + */ +FILE * +fetchPutHTTP(struct url *URL __unused, const char *flags __unused) +{ + warnx("fetchPutHTTP(): not implemented"); + return (NULL); +} + +/* + * Get an HTTP document's metadata + */ +int +fetchStatHTTP(struct url *URL, struct url_stat *us, const char *flags) +{ + FILE *f; + + f = http_request(URL, "HEAD", us, http_get_proxy(URL, flags), flags); + if (f == NULL) + return (-1); + fclose(f); + return (0); +} + +/* + * List a directory + */ +struct url_ent * +fetchListHTTP(struct url *url __unused, const char *flags __unused) +{ + warnx("fetchListHTTP(): not implemented"); + return (NULL); +} |
