/* Support for cookies. Copyright (C) 2001, 2002 Free Software Foundation, Inc. This file is part of GNU Wget. GNU Wget is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. GNU Wget is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with Wget; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. In addition, as a special exception, the Free Software Foundation gives permission to link the code of its release of Wget with the OpenSSL project's "OpenSSL" library (or with modified versions of it that use the same license as the "OpenSSL" library), and distribute the linked executables. You must obey the GNU General Public License in all respects for all of the code used other than "OpenSSL". If you modify this file, you may extend this exception to your version of the file, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version. */ /* Written by Hrvoje Niksic. Parts are loosely inspired by cookie code submitted by Tomasz Wegrzanowski. TODO: Implement limits on cookie-related sizes, such as max. cookie size, max. number of cookies, etc. Add more "cookie jar" methods, such as methods to over stored cookies, to clear temporary cookies, to perform intelligent auto-saving, etc. Ultimately support `Set-Cookie2' and `Cookie2' headers. */ #include #include #ifdef HAVE_STRING_H # include #else # include #endif #include #include #include #include "wget.h" #include "utils.h" #include "hash.h" #include "cookies.h" /* This should *really* be in a .h file! */ time_t http_atotm PARAMS ((const char *)); /* Declarations of `struct cookie' and the most basic functions. */ struct cookie_jar { /* Hash table that maps domain names to cookie chains. A "cookie chain" is a linked list of cookies that belong to the same domain. */ struct hash_table *chains_by_domain; int cookie_count; /* number of cookies in the jar. */ }; /* Value set by entry point functions, so that the low-level routines don't need to call time() all the time. */ time_t cookies_now; struct cookie_jar * cookie_jar_new (void) { struct cookie_jar *jar = xmalloc (sizeof (struct cookie_jar)); jar->chains_by_domain = make_nocase_string_hash_table (0); jar->cookie_count = 0; return jar; } struct cookie { char *domain; /* domain of the cookie */ int port; /* port number */ char *path; /* path prefix of the cookie */ int secure; /* whether cookie should be transmitted over non-https connections. */ int domain_exact; /* whether DOMAIN must match as a whole. */ int permanent; /* whether the cookie should outlive the session */ time_t expiry_time; /* time when the cookie expires */ int discard_requested; /* whether cookie was created to request discarding another cookie */ char *attr; /* cookie attribute name */ char *value; /* cookie attribute value */ struct cookie_jar *jar; /* pointer back to the cookie jar, for convenience. */ struct cookie *next; /* used for chaining of cookies in the same domain. */ }; #define PORT_ANY (-1) #define COOKIE_EXPIRED_P(c) ((c)->expiry_time != 0 && (c)->expiry_time < cookies_now) /* Allocate and return a new, empty cookie structure. */ static struct cookie * cookie_new (void) { struct cookie *cookie = xmalloc (sizeof (struct cookie)); memset (cookie, '\0', sizeof (struct cookie)); /* Both cookie->permanent and cookie->expiry_time are now 0. By default, we assume that the cookie is non-permanent and valid until the end of the session. */ cookie->port = PORT_ANY; return cookie; } /* Deallocate COOKIE and its components. */ static void delete_cookie (struct cookie *cookie) { FREE_MAYBE (cookie->domain); FREE_MAYBE (cookie->path); FREE_MAYBE (cookie->attr); FREE_MAYBE (cookie->value); xfree (cookie); } /* Functions for storing cookies. All cookies can be reached beginning with jar->chains_by_domain. The key in that table is the domain name, and the value is a linked list of all cookies from that domain. Every new cookie is placed on the head of the list. */ /* Find and return a cookie in JAR whose domain, path, and attribute name correspond to COOKIE. If found, PREVPTR will point to the location of the cookie previous in chain, or NULL if the found cookie is the head of a chain. If no matching cookie is found, return NULL. */ static struct cookie * find_matching_cookie (struct cookie_jar *jar, struct cookie *cookie, struct cookie **prevptr) { struct cookie *chain, *prev; chain = hash_table_get (jar->chains_by_domain, cookie->domain); if (!chain) goto nomatch; prev = NULL; for (; chain; prev = chain, chain = chain->next) if (0 == strcmp (cookie->path, chain->path) && 0 == strcmp (cookie->attr, chain->attr) && cookie->port == chain->port) { *prevptr = prev; return chain; } nomatch: *prevptr = NULL; return NULL; } /* Store COOKIE to the jar. This is done by placing COOKIE at the head of its chain. However, if COOKIE matches a cookie already in memory, as determined by find_matching_cookie, the old cookie is unlinked and destroyed. The key of each chain's hash table entry is allocated only the first time; next hash_table_put's reuse the same key. */ static void store_cookie (struct cookie_jar *jar, struct cookie *cookie) { struct cookie *chain_head; char *chain_key; if (hash_table_get_pair (jar->chains_by_domain, cookie->domain, &chain_key, &chain_head)) { /* A chain of cookies in this domain already exists. Check for duplicates -- if an extant cookie exactly matches our domain, port, path, and name, replace it. */ struct cookie *prev; struct cookie *victim = find_matching_cookie (jar, cookie, &prev); if (victim) { /* Remove VICTIM from the chain. COOKIE will be placed at the head. */ if (prev) { prev->next = victim->next; cookie->next = chain_head; } else { /* prev is NULL; apparently VICTIM was at the head of the chain. This place will be taken by COOKIE, so all we need to do is: */ cookie->next = victim->next; } delete_cookie (victim); --jar->cookie_count; DEBUGP (("Deleted old cookie (to be replaced.)\n")); } else cookie->next = chain_head; } else { /* We are now creating the chain. Allocate the string that will be used as a key. It is unsafe to use cookie->domain for that, because it might get deallocated by the above code at some point later. */ cookie->next = NULL; chain_key = xstrdup (cookie->domain); } hash_table_put (jar->chains_by_domain, chain_key, cookie); ++jar->cookie_count; DEBUGP (("\nStored cookie %s %d%s %s %s %d %s %s %s\n", cookie->domain, cookie->port, cookie->port == PORT_ANY ? " (ANY)" : "", cookie->path, cookie->permanent ? "permanent" : "nonpermanent", cookie->secure, cookie->expiry_time ? asctime (localtime (&cookie->expiry_time)) : "", cookie->attr, cookie->value)); } /* Discard a cookie matching COOKIE's domain, port, path, and attribute name. This gets called when we encounter a cookie whose expiry date is in the past, or whose max-age is set to 0. The former corresponds to netscape cookie spec, while the latter is specified by rfc2109. */ static void discard_matching_cookie (struct cookie_jar *jar, struct cookie *cookie) { struct cookie *prev, *victim; if (!hash_table_count (jar->chains_by_domain)) /* No elements == nothing to discard. */ return; victim = find_matching_cookie (jar, cookie, &prev); if (victim) { if (prev) /* Simply unchain the victim. */ prev->next = victim->next; else { /* VICTIM was head of its chain. We need to place a new cookie at the head. */ char *chain_key = NULL; int res; res = hash_table_get_pair (jar->chains_by_domain, victim->domain, &chain_key, NULL); assert (res != 0); if (!victim->next) { /* VICTIM was the only cookie in the chain. Destroy the chain and deallocate the chain key. */ hash_table_remove (jar->chains_by_domain, victim->domain); xfree (chain_key); } else hash_table_put (jar->chains_by_domain, chain_key, victim->next); } delete_cookie (victim); DEBUGP (("Discarded old cookie.\n")); } } /* Functions for parsing the `Set-Cookie' header, and creating new cookies from the wire. */ #define NAME_IS(string_literal) \ BOUNDED_EQUAL_NO_CASE (name_b, name_e, string_literal) #define VALUE_EXISTS (value_b && value_e) #define VALUE_NON_EMPTY (VALUE_EXISTS && (value_b != value_e)) /* Update the appropriate cookie field. [name_b, name_e) are expected to delimit the attribute name, while [value_b, value_e) (optional) should delimit the attribute value. When called the first time, it will set the cookie's attribute name and value. After that, it will check the attribute name for special fields such as `domain', `path', etc. Where appropriate, it will parse the values of the fields it recognizes and fill the corresponding fields in COOKIE. Returns 1 on success. Returns zero in case a syntax error is found; such a cookie should be discarded. */ static int update_cookie_field (struct cookie *cookie, const char *name_b, const char *name_e, const char *value_b, const char *value_e) { assert (name_b != NULL && name_e != NULL); if (!cookie->attr) { if (!VALUE_EXISTS) return 0; cookie->attr = strdupdelim (name_b, name_e); cookie->value = strdupdelim (value_b, value_e); return 1; } if (NAME_IS ("domain")) { if (!VALUE_NON_EMPTY) return 0; FREE_MAYBE (cookie->domain); /* Strictly speaking, we should set cookie->domain_exact if the domain doesn't begin with a dot. But many sites set the domain to "foo.com" and expect "subhost.foo.com" to get the cookie, and it apparently works. */ if (*value_b == '.') ++value_b; cookie->domain = strdupdelim (value_b, value_e); return 1; } else if (NAME_IS ("path")) { if (!VALUE_NON_EMPTY) return 0; FREE_MAYBE (cookie->path); cookie->path = strdupdelim (value_b, value_e); return 1; } else if (NAME_IS ("expires")) { char *value_copy; time_t expires; if (!VALUE_NON_EMPTY) return 0; BOUNDED_TO_ALLOCA (value_b, value_e, value_copy); expires = http_atotm (value_copy); if (expires != -1) { cookie->permanent = 1; cookie->expiry_time = (time_t)expires; } else /* Error in expiration spec. Assume default (cookie valid for this session.) */ ; /* According to netscape's specification, expiry time in the past means that discarding of a matching cookie is requested. */ if (cookie->expiry_time < cookies_now) cookie->discard_requested = 1; return 1; } else if (NAME_IS ("max-age")) { double maxage = -1; char *value_copy; if (!VALUE_NON_EMPTY) return 0; BOUNDED_TO_ALLOCA (value_b, value_e, value_copy); sscanf (value_copy, "%lf", &maxage); if (maxage == -1) /* something went wrong. */ return 0; cookie->permanent = 1; cookie->expiry_time = cookies_now + maxage; /* According to rfc2109, a cookie with max-age of 0 means that discarding of a matching cookie is requested. */ if (maxage == 0) cookie->discard_requested = 1; return 1; } else if (NAME_IS ("secure")) { /* ignore value completely */ cookie->secure = 1; return 1; } else /* Unrecognized attribute; ignore it. */ return 1; } #undef NAME_IS /* Returns non-zero for characters that are legal in the name of an attribute. This used to allow only alphanumerics, '-', and '_', but we need to be more lenient because a number of sites wants to use weirder attribute names. rfc2965 "informally specifies" attribute name (token) as "a sequence of non-special, non-white space characters". So we allow everything except the stuff we know could harm us. */ #define ATTR_NAME_CHAR(c) ((c) > 32 && (c) < 127 \ && (c) != '"' && (c) != '=' \ && (c) != ';' && (c) != ',') /* Parse the contents of the `Set-Cookie' header. The header looks like this: name1=value1; name2=value2; ... Trailing semicolon is optional; spaces are allowed between all tokens. Additionally, values may be quoted. A new cookie is returned upon success, NULL otherwise. The specified CALLBACK function (normally `update_cookie_field' is used to update the fields of the newly created cookie structure. */ static struct cookie * parse_set_cookies (const char *sc, int (*callback) (struct cookie *, const char *, const char *, const char *, const char *), int silent) { struct cookie *cookie = cookie_new (); /* #### Hand-written DFAs are no fun to debug. We'de be better off to rewrite this as an inline parser. */ enum { S_START, S_NAME, S_NAME_POST, S_VALUE_PRE, S_VALUE, S_QUOTED_VALUE, S_VALUE_TRAILSPACE, S_ATTR_ACTION, S_DONE, S_ERROR } state = S_START; const char *p = sc; char c; const char *name_b = NULL, *name_e = NULL; const char *value_b = NULL, *value_e = NULL; c = *p; while (state != S_DONE && state != S_ERROR) { switch (state) { case S_START: if (!c) state = S_DONE; else if (ISSPACE (c)) /* Strip all whitespace preceding the name. */ c = *++p; else if (ATTR_NAME_CHAR (c)) { name_b = p; state = S_NAME; } else /* empty attr name not allowed */ state = S_ERROR; break; case S_NAME: if (!c || c == ';' || c == '=' || ISSPACE (c)) { name_e = p; state = S_NAME_POST; } else if (ATTR_NAME_CHAR (c)) c = *++p; else state = S_ERROR; break; case S_NAME_POST: if (!c || c == ';') { value_b = value_e = NULL; if (c == ';') c = *++p; state = S_ATTR_ACTION; } else if (c == '=') { c = *++p; state = S_VALUE_PRE; } else if (ISSPACE (c)) /* Ignore space and keep the state. */ c = *++p; else state = S_ERROR; break; case S_VALUE_PRE: if (!c || c == ';') { value_b = value_e = p; if (c == ';') c = *++p; state = S_ATTR_ACTION; } else if (c == '"') { c = *++p; value_b = p; state = S_QUOTED_VALUE; } else if (ISSPACE (c)) c = *++p; else { value_b = p; value_e = NULL; state = S_VALUE; } break; case S_VALUE: if (!c || c == ';' || ISSPACE (c)) { value_e = p; state = S_VALUE_TRAILSPACE; } else { value_e = NULL; /* no trailing space */ c = *++p; } break; case S_QUOTED_VALUE: if (c == '"') { value_e = p; c = *++p; state = S_VALUE_TRAILSPACE; } else if (!c) state = S_ERROR; else c = *++p; break; case S_VALUE_TRAILSPACE: if (c == ';') { c = *++p; state = S_ATTR_ACTION; } else if (!c) state = S_ATTR_ACTION; else if (ISSPACE (c)) c = *++p; else state = S_VALUE; break; case S_ATTR_ACTION: { int legal = callback (cookie, name_b, name_e, value_b, value_e); if (!legal) { if (!silent) { char *name; BOUNDED_TO_ALLOCA (name_b, name_e, name); logprintf (LOG_NOTQUIET, _("Error in Set-Cookie, field `%s'"), name); } state = S_ERROR; break; } state = S_START; } break; case S_DONE: case S_ERROR: /* handled by loop condition */ break; } } if (state == S_DONE) return cookie; delete_cookie (cookie); if (state != S_ERROR) abort (); if (!silent) logprintf (LOG_NOTQUIET, _("Syntax error in Set-Cookie: %s at position %d.\n"), sc, p - sc); return NULL; } /* Sanity checks. These are important, otherwise it is possible for mailcious attackers to destroy important cookie information and/or violate your privacy. */ #define REQUIRE_DIGITS(p) do { \ if (!ISDIGIT (*p)) \ return 0; \ for (++p; ISDIGIT (*p); p++) \ ; \ } while (0) #define REQUIRE_DOT(p) do { \ if (*p++ != '.') \ return 0; \ } while (0) /* Check whether ADDR matches .... We don't want to call network functions like inet_addr() because all we need is a check, preferrably one that is small, fast, and well-defined. */ static int numeric_address_p (const char *addr) { const char *p = addr; REQUIRE_DIGITS (p); /* A */ REQUIRE_DOT (p); /* . */ REQUIRE_DIGITS (p); /* B */ REQUIRE_DOT (p); /* . */ REQUIRE_DIGITS (p); /* C */ REQUIRE_DOT (p); /* . */ REQUIRE_DIGITS (p); /* D */ if (*p != '\0') return 0; return 1; } /* Check whether COOKIE_DOMAIN is an appropriate domain for HOST. Originally I tried to make the check compliant with rfc2109, but the sites deviated too often, so I had to fall back to "tail matching", as defined by the original Netscape's cookie spec. */ static int check_domain_match (const char *cookie_domain, const char *host) { DEBUGP (("cdm: 1")); /* Numeric address requires exact match. It also requires HOST to be an IP address. */ if (numeric_address_p (cookie_domain)) return 0 == strcmp (cookie_domain, host); DEBUGP ((" 2")); /* For the sake of efficiency, check for exact match first. */ if (0 == strcasecmp (cookie_domain, host)) return 1; DEBUGP ((" 3")); /* HOST must match the tail of cookie_domain. */ if (!match_tail (host, cookie_domain, 1)) return 0; /* We know that COOKIE_DOMAIN is a subset of HOST; however, we must make sure that somebody is not trying to set the cookie for a subdomain shared by many entities. For example, "company.co.uk" must not be allowed to set a cookie for ".co.uk". On the other hand, "sso.redhat.de" should be able to set a cookie for ".redhat.de". The only marginally sane way to handle this I can think of is to reject on the basis of the length of the second-level domain name (but when the top-level domain is unknown), with the assumption that those of three or less characters could be reserved. For example: .co.org -> works because the TLD is known .co.uk -> doesn't work because "co" is only two chars long .com.au -> doesn't work because "com" is only 3 chars long .cnn.uk -> doesn't work because "cnn" is also only 3 chars long (ugh) .cnn.de -> doesn't work for the same reason (ugh!!) .abcd.de -> works because "abcd" is 4 chars long .img.cnn.de -> works because it's not trying to set the 2nd level domain .cnn.co.uk -> works for the same reason That should prevent misuse, while allowing reasonable usage. If someone knows of a better way to handle this, please let me know. */ { const char *p = cookie_domain; int dccount = 1; /* number of domain components */ int ldcl = 0; /* last domain component length */ int nldcl = 0; /* next to last domain component length */ int out; if (*p == '.') /* Ignore leading period in this calculation. */ ++p; DEBUGP ((" 4")); for (out = 0; !out; p++) switch (*p) { case '\0': out = 1; break; case '.': if (ldcl == 0) /* Empty domain component found -- the domain is invalid. */ return 0; if (*(p + 1) == '\0') { /* Tolerate trailing '.' by not treating the domain as one ending with an empty domain component. */ out = 1; break; } nldcl = ldcl; ldcl = 0; ++dccount; break; default: ++ldcl; } DEBUGP ((" 5")); if (dccount < 2) return 0; DEBUGP ((" 6")); if (dccount == 2) { int i; int known_toplevel = 0; static char *known_toplevel_domains[] = { ".com", ".edu", ".net", ".org", ".gov", ".mil", ".int" }; for (i = 0; i < countof (known_toplevel_domains); i++) if (match_tail (cookie_domain, known_toplevel_domains[i], 1)) { known_toplevel = 1; break; } if (!known_toplevel && nldcl <= 3) return 0; } } DEBUGP ((" 7")); /* Don't allow domain "bar.com" to match host "foobar.com". */ if (*cookie_domain != '.') { int dlen = strlen (cookie_domain); int hlen = strlen (host); /* cookie host: hostname.foobar.com */ /* desired domain: bar.com */ /* '.' must be here in host-> ^ */ if (hlen > dlen && host[hlen - dlen - 1] != '.') return 0; } DEBUGP ((" 8")); return 1; } static int path_matches PARAMS ((const char *, const char *)); /* Check whether PATH begins with COOKIE_PATH. */ static int check_path_match (const char *cookie_path, const char *path) { return path_matches (path, cookie_path); } /* Process the HTTP `Set-Cookie' header. This results in storing the cookie or discarding a matching one, or ignoring it completely, all depending on the contents. */ void cookie_jar_process_set_cookie (struct cookie_jar *jar, const char *host, int port, const char *path, const char *set_cookie) { struct cookie *cookie; cookies_now = time (NULL); cookie = parse_set_cookies (set_cookie, update_cookie_field, 0); if (!cookie) goto out; /* Sanitize parts of cookie. */ if (!cookie->domain) { copy_domain: cookie->domain = xstrdup (host); cookie->port = port; } else { if (!check_domain_match (cookie->domain, host)) { logprintf (LOG_NOTQUIET, "Cookie coming from %s attempted to set domain to %s\n", host, cookie->domain); goto copy_domain; } } if (!cookie->path) cookie->path = xstrdup (path); else { if (!check_path_match (cookie->path, path)) { DEBUGP (("Attempt to fake the path: %s, %s\n", cookie->path, path)); goto out; } } if (cookie->discard_requested) { discard_matching_cookie (jar, cookie); goto out; } store_cookie (jar, cookie); return; out: if (cookie) delete_cookie (cookie); } /* Support for sending out cookies in HTTP requests, based on previously stored cookies. Entry point is `build_cookies_request'. */ /* Find the cookie chains that match HOST and store them to DEST. A cookie chain is the list of cookies declared under a domain. Given HOST "img.search.xemacs.org", this function will store the chains for "img.search.xemacs.org", "search.xemacs.org", and "xemacs.org" -- those of them that exist (if any), that is. No more than SIZE matches are written; if more matches are present, return the number of chains that would have been written. */ static int find_matching_chains (struct cookie_jar *jar, const char *host, struct cookie *dest[], int dest_size) { int dest_count = 0; int passes, passcnt; if (!hash_table_count (jar->chains_by_domain)) return 0; if (numeric_address_p (host)) /* If host is an IP address, only check for the exact match. */ passes = 1; else /* Otherwise, check all the subdomains except the top-level (last) one. As a domain with N components has N-1 dots, the number of passes equals the number of dots. */ passes = count_char (host, '.'); passcnt = 0; /* Find chains that match HOST, starting with exact match and progressing to less specific domains. For instance, given HOST fly.srk.fer.hr, first look for fly.srk.fer.hr's chain, then srk.fer.hr's, then fer.hr's. */ while (1) { struct cookie *chain = hash_table_get (jar->chains_by_domain, host); if (chain) { if (dest_count < dest_size) dest[dest_count] = chain; ++dest_count; } if (++passcnt >= passes) break; host = strchr (host, '.') + 1; } return dest_count; } /* If FULL_PATH begins with PREFIX, return the length of PREFIX, zero otherwise. */ static int path_matches (const char *full_path, const char *prefix) { int len; if (*prefix != '/') /* Wget's HTTP paths do not begin with '/' (the URL code treats it as a separator), but the '/' is assumed when matching against the cookie stuff. */ return 0; ++prefix; len = strlen (prefix); if (0 != strncmp (full_path, prefix, len)) /* FULL_PATH doesn't begin with PREFIX. */ return 0; /* Length of PREFIX determines the quality of the match. */ return len + 1; } /* Return non-zero iff COOKIE matches the given HOST, PORT, PATH, and SECFLAG. If PATH_GOODNESS is non-NULL, store the "path goodness" value there. That value is a measure of how well COOKIE matches PATH, used for ordering cookies. */ static int matching_cookie (const struct cookie *cookie, const char *host, int port, const char *path, int secure, int *path_goodness) { int pg; if (COOKIE_EXPIRED_P (cookie)) /* Ignore stale cookies. Don't bother unchaining the cookie at this point -- Wget is a relatively short-lived application, and stale cookies will not be saved by `save_cookies'. On the other hand, this function should be as efficient as possible. */ return 0; if (cookie->secure && !secure) /* Don't transmit secure cookies over insecure connections. */ return 0; if (cookie->port != PORT_ANY && cookie->port != port) return 0; /* If exact domain match is required, verify that cookie's domain is equal to HOST. If not, assume success on the grounds of the cookie's chain having been found by find_matching_chains. */ if (cookie->domain_exact && 0 != strcasecmp (host, cookie->domain)) return 0; pg = path_matches (path, cookie->path); if (!pg) return 0; if (path_goodness) /* If the caller requested path_goodness, we return it. This is an optimization, so that the caller doesn't need to call path_matches() again. */ *path_goodness = pg; return 1; } /* A structure that points to a cookie, along with the additional information about the cookie's "goodness". This allows us to sort the cookies when returning them to the server, as required by the spec. */ struct weighed_cookie { struct cookie *cookie; int domain_goodness; int path_goodness; }; /* Comparator used for uniquifying the list. */ static int equality_comparator (const void *p1, const void *p2) { struct weighed_cookie *wc1 = (struct weighed_cookie *)p1; struct weighed_cookie *wc2 = (struct weighed_cookie *)p2; int namecmp = strcmp (wc1->cookie->attr, wc2->cookie->attr); int valuecmp = strcmp (wc1->cookie->value, wc2->cookie->value); /* We only really care whether both name and value are equal. We return them in this order only for consistency... */ return namecmp ? namecmp : valuecmp; } /* Eliminate duplicate cookies. "Duplicate cookies" are any two cookies whose name and value are the same. Whenever a duplicate pair is found, one of the cookies is removed. */ static int eliminate_dups (struct weighed_cookie *outgoing, int count) { int i; /* We deploy a simple uniquify algorithm: first sort the array according to our sort criteria, then uniquify it by comparing each cookie with its neighbor. */ qsort (outgoing, count, sizeof (struct weighed_cookie), equality_comparator); for (i = 0; i < count - 1; i++) { struct cookie *c1 = outgoing[i].cookie; struct cookie *c2 = outgoing[i + 1].cookie; if (!strcmp (c1->attr, c2->attr) && !strcmp (c1->value, c2->value)) { /* c1 and c2 are the same; get rid of c2. */ if (count > i + 1) /* move all ptrs from positions [i + 1, count) to i. */ memmove (outgoing + i, outgoing + i + 1, (count - (i + 1)) * sizeof (struct weighed_cookie)); /* We decrement i to counter the ++i above. Remember that we've just removed the element in front of us; we need to remain in place to check whether outgoing[i] matches what used to be outgoing[i + 2]. */ --i; --count; } } return count; } /* Comparator used for sorting by quality. */ static int goodness_comparator (const void *p1, const void *p2) { struct weighed_cookie *wc1 = (struct weighed_cookie *)p1; struct weighed_cookie *wc2 = (struct weighed_cookie *)p2; /* Subtractions take `wc2' as the first argument becauase we want a sort in *decreasing* order of goodness. */ int dgdiff = wc2->domain_goodness - wc1->domain_goodness; int pgdiff = wc2->path_goodness - wc1->path_goodness; /* Sort by domain goodness; if these are the same, sort by path goodness. (The sorting order isn't really specified; maybe it should be the other way around.) */ return dgdiff ? dgdiff : pgdiff; } /* Generate a `Cookie' header for a request that goes to HOST:PORT and requests PATH from the server. The resulting string is allocated with `malloc', and the caller is responsible for freeing it. If no cookies pertain to this request, i.e. no cookie header should be generated, NULL is returned. */ char * cookie_jar_generate_cookie_header (struct cookie_jar *jar, const char *host, int port, const char *path, int connection_secure_p) { struct cookie *chain_default_store[5]; struct cookie **chains = chain_default_store; int chain_store_size = countof (chain_default_store); int chain_count; struct cookie *cookie; struct weighed_cookie *outgoing; int count, i, ocnt; char *result; int result_size, pos; /* First, find the chains that match HOST. */ again: chain_count = find_matching_chains (jar, host, chains, chain_store_size); if (chain_count > chain_store_size) { /* It's unlikely that more than 5 chains will ever match. But since find_matching_chains reports the exact size it needs, it's easy to not have the limitation, so we don't. */ chains = alloca (chain_count * sizeof (struct cookie *)); chain_store_size = chain_count; goto again; } if (!chain_count) return NULL; cookies_now = time (NULL); /* Now extract from the chains those cookies that match our host (for domain_exact cookies), port (for cookies with port other than PORT_ANY), etc. See matching_cookie for details. */ /* Count the number of matching cookies. */ count = 0; for (i = 0; i < chain_count; i++) for (cookie = chains[i]; cookie; cookie = cookie->next) if (matching_cookie (cookie, host, port, path, connection_secure_p, NULL)) ++count; if (!count) return NULL; /* no cookies matched */ /* Allocate the array. */ outgoing = alloca (count * sizeof (struct weighed_cookie)); /* Fill the array with all the matching cookies from the chains that match HOST. */ ocnt = 0; for (i = 0; i < chain_count; i++) for (cookie = chains[i]; cookie; cookie = cookie->next) { int pg; if (!matching_cookie (cookie, host, port, path, connection_secure_p, &pg)) continue; outgoing[ocnt].cookie = cookie; outgoing[ocnt].domain_goodness = strlen (cookie->domain); outgoing[ocnt].path_goodness = pg; ++ocnt; } assert (ocnt == count); /* Eliminate duplicate cookies; that is, those whose name and value are the same. */ count = eliminate_dups (outgoing, count); /* Sort the array so that best-matching domains come first, and that, within one domain, best-matching paths come first. */ qsort (outgoing, count, sizeof (struct weighed_cookie), goodness_comparator); /* Count the space the name=value pairs will take. */ result_size = 0; for (i = 0; i < count; i++) { struct cookie *c = outgoing[i].cookie; /* name=value */ result_size += strlen (c->attr) + 1 + strlen (c->value); } /* Allocate output buffer: "Cookie: " -- 8 name=value pairs -- result_size "; " separators -- (count - 1) * 2 \r\n line ending -- 2 \0 terminator -- 1 */ result_size = 8 + result_size + (count - 1) * 2 + 2 + 1; result = xmalloc (result_size); pos = 0; strcpy (result, "Cookie: "); pos += 8; for (i = 0; i < count; i++) { struct cookie *c = outgoing[i].cookie; int namlen = strlen (c->attr); int vallen = strlen (c->value); memcpy (result + pos, c->attr, namlen); pos += namlen; result[pos++] = '='; memcpy (result + pos, c->value, vallen); pos += vallen; if (i < count - 1) { result[pos++] = ';'; result[pos++] = ' '; } } result[pos++] = '\r'; result[pos++] = '\n'; result[pos++] = '\0'; assert (pos == result_size); return result; } /* Support for loading and saving cookies. The format used for loading and saving should be the format of the `cookies.txt' file used by Netscape and Mozilla, at least the Unix versions. (Apparently IE can export cookies in that format as well.) The format goes like this: DOMAIN DOMAIN-FLAG PATH SECURE-FLAG TIMESTAMP ATTR-NAME ATTR-VALUE DOMAIN -- cookie domain, optionally followed by :PORT DOMAIN-FLAG -- whether all hosts in the domain match PATH -- cookie path SECURE-FLAG -- whether cookie requires secure connection TIMESTAMP -- expiry timestamp, number of seconds since epoch ATTR-NAME -- name of the cookie attribute ATTR-VALUE -- value of the cookie attribute (empty if absent) The fields are separated by TABs. All fields are mandatory, except for ATTR-VALUE. The `-FLAG' fields are boolean, their legal values being "TRUE" and "FALSE'. Empty lines, lines consisting of whitespace only, and comment lines (beginning with # optionally preceded by whitespace) are ignored. Example line from cookies.txt (split in two lines for readability): .google.com TRUE / FALSE 2147368447 \ PREF ID=34bb47565bbcd47b:LD=en:NR=20:TM=985172580:LM=985739012 */ /* If the region [B, E) ends with :, parse the number, return it, and store new boundary (location of the `:') to DOMAIN_E_PTR. If port is not specified, return 0. */ static int domain_port (const char *domain_b, const char *domain_e, const char **domain_e_ptr) { int port = 0; const char *p; const char *colon = memchr (domain_b, ':', domain_e - domain_b); if (!colon) return 0; for (p = colon + 1; p < domain_e && ISDIGIT (*p); p++) port = 10 * port + (*p - '0'); if (p < domain_e) /* Garbage following port number. */ return 0; *domain_e_ptr = colon; return port; } #define GET_WORD(p, b, e) do { \ b = p; \ while (*p && *p != '\t') \ ++p; \ e = p; \ if (b == e || !*p) \ goto next; \ ++p; \ } while (0) /* Load cookies from FILE. */ void cookie_jar_load (struct cookie_jar *jar, const char *file) { char *line; FILE *fp = fopen (file, "r"); if (!fp) { logprintf (LOG_NOTQUIET, "Cannot open cookies file `%s': %s\n", file, strerror (errno)); return; } cookies_now = time (NULL); for (; ((line = read_whole_line (fp)) != NULL); xfree (line)) { struct cookie *cookie; char *p = line; double expiry; int port; char *domain_b = NULL, *domain_e = NULL; char *domflag_b = NULL, *domflag_e = NULL; char *path_b = NULL, *path_e = NULL; char *secure_b = NULL, *secure_e = NULL; char *expires_b = NULL, *expires_e = NULL; char *name_b = NULL, *name_e = NULL; char *value_b = NULL, *value_e = NULL; /* Skip leading white-space. */ while (*p && ISSPACE (*p)) ++p; /* Ignore empty lines. */ if (!*p || *p == '#') continue; GET_WORD (p, domain_b, domain_e); GET_WORD (p, domflag_b, domflag_e); GET_WORD (p, path_b, path_e); GET_WORD (p, secure_b, secure_e); GET_WORD (p, expires_b, expires_e); GET_WORD (p, name_b, name_e); /* Don't use GET_WORD for value because it ends with newline, not TAB. */ value_b = p; value_e = p + strlen (p); if (value_e > value_b && value_e[-1] == '\n') --value_e; if (value_e > value_b && value_e[-1] == '\r') --value_e; /* Empty values are legal (I think), so don't bother checking. */ cookie = cookie_new (); cookie->attr = strdupdelim (name_b, name_e); cookie->value = strdupdelim (value_b, value_e); cookie->path = strdupdelim (path_b, path_e); cookie->secure = BOUNDED_EQUAL (secure_b, secure_e, "TRUE"); /* Curl source says, quoting Andre Garcia: "flag: A TRUE/FALSE value indicating if all machines within a given domain can access the variable. This value is set automatically by the browser, depending on the value set for the domain." */ cookie->domain_exact = !BOUNDED_EQUAL (domflag_b, domflag_e, "TRUE"); /* DOMAIN needs special treatment because we might need to extract the port. */ port = domain_port (domain_b, domain_e, (const char **)&domain_e); if (port) cookie->port = port; if (*domain_b == '.') ++domain_b; /* remove leading dot internally */ cookie->domain = strdupdelim (domain_b, domain_e); /* safe default in case EXPIRES field is garbled. */ expiry = (double)cookies_now - 1; /* I don't like changing the line, but it's safe here. (line is malloced.) */ *expires_e = '\0'; sscanf (expires_b, "%lf", &expiry); if (expiry < cookies_now) /* ignore stale cookie. */ goto abort; cookie->expiry_time = expiry; /* If the cookie has survived being saved into an external file, it is obviously permanent. */ cookie->permanent = 1; store_cookie (jar, cookie); next: continue; abort: delete_cookie (cookie); } fclose (fp); } /* Mapper for save_cookies callable by hash_table_map. VALUE points to the head in a chain of cookies. The function prints the entire chain. */ static int save_cookies_mapper (void *key, void *value, void *arg) { FILE *fp = (FILE *)arg; char *domain = (char *)key; struct cookie *cookie = (struct cookie *)value; for (; cookie; cookie = cookie->next) { if (!cookie->permanent) continue; if (COOKIE_EXPIRED_P (cookie)) continue; if (!cookie->domain_exact) fputc ('.', fp); fputs (domain, fp); if (cookie->port != PORT_ANY) fprintf (fp, ":%d", cookie->port); fprintf (fp, "\t%s\t%s\t%s\t%.0f\t%s\t%s\n", cookie->domain_exact ? "FALSE" : "TRUE", cookie->path, cookie->secure ? "TRUE" : "FALSE", (double)cookie->expiry_time, cookie->attr, cookie->value); if (ferror (fp)) return 1; /* stop mapping */ } return 0; } /* Save cookies, in format described above, to FILE. */ void cookie_jar_save (struct cookie_jar *jar, const char *file) { FILE *fp; DEBUGP (("Saving cookies to %s.\n", file)); cookies_now = time (NULL); fp = fopen (file, "w"); if (!fp) { logprintf (LOG_NOTQUIET, _("Cannot open cookies file `%s': %s\n"), file, strerror (errno)); return; } fputs ("# HTTP cookie file.\n", fp); fprintf (fp, "# Generated by Wget on %s.\n", datetime_str (NULL)); fputs ("# Edit at your own risk.\n\n", fp); hash_table_map (jar->chains_by_domain, save_cookies_mapper, fp); if (ferror (fp)) logprintf (LOG_NOTQUIET, _("Error writing to `%s': %s\n"), file, strerror (errno)); if (fclose (fp) < 0) logprintf (LOG_NOTQUIET, _("Error closing `%s': %s\n"), file, strerror (errno)); DEBUGP (("Done saving cookies.\n")); } /* Destroy all the elements in the chain and unhook it from the cookie jar. This is written in the form of a callback to hash_table_map and used by cookie_jar_delete to delete all the cookies in a jar. */ static int nuke_cookie_chain (void *value, void *key, void *arg) { char *chain_key = (char *)value; struct cookie *chain = (struct cookie *)key; struct cookie_jar *jar = (struct cookie_jar *)arg; /* Remove the chain from the table and free the key. */ hash_table_remove (jar->chains_by_domain, chain_key); xfree (chain_key); /* Then delete all the cookies in the chain. */ while (chain) { struct cookie *next = chain->next; delete_cookie (chain); chain = next; } /* Keep mapping. */ return 0; } /* Clean up cookie-related data. */ void cookie_jar_delete (struct cookie_jar *jar) { hash_table_map (jar->chains_by_domain, nuke_cookie_chain, jar); hash_table_destroy (jar->chains_by_domain); xfree (jar); } /* Test cases. Currently this is only tests parse_set_cookies. To use, recompile Wget with -DTEST_COOKIES and call test_cookies() from main. */ #ifdef TEST_COOKIES int test_count; char *test_results[10]; static int test_parse_cookies_callback (struct cookie *ignored, const char *nb, const char *ne, const char *vb, const char *ve) { test_results[test_count++] = strdupdelim (nb, ne); test_results[test_count++] = strdupdelim (vb, ve); return 1; } void test_cookies (void) { /* Tests expected to succeed: */ static struct { char *data; char *results[10]; } tests_succ[] = { { "", {NULL} }, { "arg=value", {"arg", "value", NULL} }, { "arg1=value1;arg2=value2", {"arg1", "value1", "arg2", "value2", NULL} }, { "arg1=value1; arg2=value2", {"arg1", "value1", "arg2", "value2", NULL} }, { "arg1=value1; arg2=value2;", {"arg1", "value1", "arg2", "value2", NULL} }, { "arg1=value1; arg2=value2; ", {"arg1", "value1", "arg2", "value2", NULL} }, { "arg1=\"value1\"; arg2=\"\"", {"arg1", "value1", "arg2", "", NULL} }, { "arg=", {"arg", "", NULL} }, { "arg1=; arg2=", {"arg1", "", "arg2", "", NULL} }, { "arg1 = ; arg2= ", {"arg1", "", "arg2", "", NULL} }, }; /* Tests expected to fail: */ static char *tests_fail[] = { ";", "arg=\"unterminated", "=empty-name", "arg1=;=another-empty-name", }; int i; for (i = 0; i < countof (tests_succ); i++) { int ind; char *data = tests_succ[i].data; char **expected = tests_succ[i].results; struct cookie *c; test_count = 0; c = parse_set_cookies (data, test_parse_cookies_callback, 1); if (!c) { printf ("NULL cookie returned for valid data: %s\n", data); continue; } for (ind = 0; ind < test_count; ind += 2) { if (!expected[ind]) break; if (0 != strcmp (expected[ind], test_results[ind])) printf ("Invalid name %d for '%s' (expected '%s', got '%s')\n", ind / 2 + 1, data, expected[ind], test_results[ind]); if (0 != strcmp (expected[ind + 1], test_results[ind + 1])) printf ("Invalid value %d for '%s' (expected '%s', got '%s')\n", ind / 2 + 1, data, expected[ind + 1], test_results[ind + 1]); } if (ind < test_count || expected[ind]) printf ("Unmatched number of results: %s\n", data); } for (i = 0; i < countof (tests_fail); i++) { struct cookie *c; char *data = tests_fail[i]; test_count = 0; c = parse_set_cookies (data, test_parse_cookies_callback, 1); if (c) printf ("Failed to report error on invalid data: %s\n", data); } } #endif /* TEST_COOKIES */