From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- net/rxrpc/key.c | 695 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 695 insertions(+) create mode 100644 net/rxrpc/key.c (limited to 'net/rxrpc/key.c') diff --git a/net/rxrpc/key.c b/net/rxrpc/key.c new file mode 100644 index 000000000..8d2073e0e --- /dev/null +++ b/net/rxrpc/key.c @@ -0,0 +1,695 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* RxRPC key management + * + * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * RxRPC keys should have a description of describing their purpose: + * "afs@example.com" + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "ar-internal.h" + +static int rxrpc_preparse(struct key_preparsed_payload *); +static void rxrpc_free_preparse(struct key_preparsed_payload *); +static void rxrpc_destroy(struct key *); +static void rxrpc_describe(const struct key *, struct seq_file *); +static long rxrpc_read(const struct key *, char *, size_t); + +/* + * rxrpc defined keys take an arbitrary string as the description and an + * arbitrary blob of data as the payload + */ +struct key_type key_type_rxrpc = { + .name = "rxrpc", + .flags = KEY_TYPE_NET_DOMAIN, + .preparse = rxrpc_preparse, + .free_preparse = rxrpc_free_preparse, + .instantiate = generic_key_instantiate, + .destroy = rxrpc_destroy, + .describe = rxrpc_describe, + .read = rxrpc_read, +}; +EXPORT_SYMBOL(key_type_rxrpc); + +/* + * parse an RxKAD type XDR format token + * - the caller guarantees we have at least 4 words + */ +static int rxrpc_preparse_xdr_rxkad(struct key_preparsed_payload *prep, + size_t datalen, + const __be32 *xdr, unsigned int toklen) +{ + struct rxrpc_key_token *token, **pptoken; + time64_t expiry; + size_t plen; + u32 tktlen; + + _enter(",{%x,%x,%x,%x},%u", + ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]), + toklen); + + if (toklen <= 8 * 4) + return -EKEYREJECTED; + tktlen = ntohl(xdr[7]); + _debug("tktlen: %x", tktlen); + if (tktlen > AFSTOKEN_RK_TIX_MAX) + return -EKEYREJECTED; + if (toklen < 8 * 4 + tktlen) + return -EKEYREJECTED; + + plen = sizeof(*token) + sizeof(*token->kad) + tktlen; + prep->quotalen = datalen + plen; + + plen -= sizeof(*token); + token = kzalloc(sizeof(*token), GFP_KERNEL); + if (!token) + return -ENOMEM; + + token->kad = kzalloc(plen, GFP_KERNEL); + if (!token->kad) { + kfree(token); + return -ENOMEM; + } + + token->security_index = RXRPC_SECURITY_RXKAD; + token->kad->ticket_len = tktlen; + token->kad->vice_id = ntohl(xdr[0]); + token->kad->kvno = ntohl(xdr[1]); + token->kad->start = ntohl(xdr[4]); + token->kad->expiry = ntohl(xdr[5]); + token->kad->primary_flag = ntohl(xdr[6]); + memcpy(&token->kad->session_key, &xdr[2], 8); + memcpy(&token->kad->ticket, &xdr[8], tktlen); + + _debug("SCIX: %u", token->security_index); + _debug("TLEN: %u", token->kad->ticket_len); + _debug("EXPY: %x", token->kad->expiry); + _debug("KVNO: %u", token->kad->kvno); + _debug("PRIM: %u", token->kad->primary_flag); + _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x", + token->kad->session_key[0], token->kad->session_key[1], + token->kad->session_key[2], token->kad->session_key[3], + token->kad->session_key[4], token->kad->session_key[5], + token->kad->session_key[6], token->kad->session_key[7]); + if (token->kad->ticket_len >= 8) + _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x", + token->kad->ticket[0], token->kad->ticket[1], + token->kad->ticket[2], token->kad->ticket[3], + token->kad->ticket[4], token->kad->ticket[5], + token->kad->ticket[6], token->kad->ticket[7]); + + /* count the number of tokens attached */ + prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1); + + /* attach the data */ + for (pptoken = (struct rxrpc_key_token **)&prep->payload.data[0]; + *pptoken; + pptoken = &(*pptoken)->next) + continue; + *pptoken = token; + expiry = rxrpc_u32_to_time64(token->kad->expiry); + if (expiry < prep->expiry) + prep->expiry = expiry; + + _leave(" = 0"); + return 0; +} + +/* + * attempt to parse the data as the XDR format + * - the caller guarantees we have more than 7 words + */ +static int rxrpc_preparse_xdr(struct key_preparsed_payload *prep) +{ + const __be32 *xdr = prep->data, *token, *p; + const char *cp; + unsigned int len, paddedlen, loop, ntoken, toklen, sec_ix; + size_t datalen = prep->datalen; + int ret, ret2; + + _enter(",{%x,%x,%x,%x},%zu", + ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]), + prep->datalen); + + if (datalen > AFSTOKEN_LENGTH_MAX) + goto not_xdr; + + /* XDR is an array of __be32's */ + if (datalen & 3) + goto not_xdr; + + /* the flags should be 0 (the setpag bit must be handled by + * userspace) */ + if (ntohl(*xdr++) != 0) + goto not_xdr; + datalen -= 4; + + /* check the cell name */ + len = ntohl(*xdr++); + if (len < 1 || len > AFSTOKEN_CELL_MAX) + goto not_xdr; + datalen -= 4; + paddedlen = (len + 3) & ~3; + if (paddedlen > datalen) + goto not_xdr; + + cp = (const char *) xdr; + for (loop = 0; loop < len; loop++) + if (!isprint(cp[loop])) + goto not_xdr; + for (; loop < paddedlen; loop++) + if (cp[loop]) + goto not_xdr; + _debug("cellname: [%u/%u] '%*.*s'", + len, paddedlen, len, len, (const char *) xdr); + datalen -= paddedlen; + xdr += paddedlen >> 2; + + /* get the token count */ + if (datalen < 12) + goto not_xdr; + ntoken = ntohl(*xdr++); + datalen -= 4; + _debug("ntoken: %x", ntoken); + if (ntoken < 1 || ntoken > AFSTOKEN_MAX) + goto not_xdr; + + /* check each token wrapper */ + p = xdr; + loop = ntoken; + do { + if (datalen < 8) + goto not_xdr; + toklen = ntohl(*p++); + sec_ix = ntohl(*p); + datalen -= 4; + _debug("token: [%x/%zx] %x", toklen, datalen, sec_ix); + paddedlen = (toklen + 3) & ~3; + if (toklen < 20 || toklen > datalen || paddedlen > datalen) + goto not_xdr; + datalen -= paddedlen; + p += paddedlen >> 2; + + } while (--loop > 0); + + _debug("remainder: %zu", datalen); + if (datalen != 0) + goto not_xdr; + + /* okay: we're going to assume it's valid XDR format + * - we ignore the cellname, relying on the key to be correctly named + */ + ret = -EPROTONOSUPPORT; + do { + toklen = ntohl(*xdr++); + token = xdr; + xdr += (toklen + 3) / 4; + + sec_ix = ntohl(*token++); + toklen -= 4; + + _debug("TOKEN type=%x len=%x", sec_ix, toklen); + + switch (sec_ix) { + case RXRPC_SECURITY_RXKAD: + ret2 = rxrpc_preparse_xdr_rxkad(prep, datalen, token, toklen); + break; + default: + ret2 = -EPROTONOSUPPORT; + break; + } + + switch (ret2) { + case 0: + ret = 0; + break; + case -EPROTONOSUPPORT: + break; + case -ENOPKG: + if (ret != 0) + ret = -ENOPKG; + break; + default: + ret = ret2; + goto error; + } + + } while (--ntoken > 0); + +error: + _leave(" = %d", ret); + return ret; + +not_xdr: + _leave(" = -EPROTO"); + return -EPROTO; +} + +/* + * Preparse an rxrpc defined key. + * + * Data should be of the form: + * OFFSET LEN CONTENT + * 0 4 key interface version number + * 4 2 security index (type) + * 6 2 ticket length + * 8 4 key expiry time (time_t) + * 12 4 kvno + * 16 8 session key + * 24 [len] ticket + * + * if no data is provided, then a no-security key is made + */ +static int rxrpc_preparse(struct key_preparsed_payload *prep) +{ + const struct rxrpc_key_data_v1 *v1; + struct rxrpc_key_token *token, **pp; + time64_t expiry; + size_t plen; + u32 kver; + int ret; + + _enter("%zu", prep->datalen); + + /* handle a no-security key */ + if (!prep->data && prep->datalen == 0) + return 0; + + /* determine if the XDR payload format is being used */ + if (prep->datalen > 7 * 4) { + ret = rxrpc_preparse_xdr(prep); + if (ret != -EPROTO) + return ret; + } + + /* get the key interface version number */ + ret = -EINVAL; + if (prep->datalen <= 4 || !prep->data) + goto error; + memcpy(&kver, prep->data, sizeof(kver)); + prep->data += sizeof(kver); + prep->datalen -= sizeof(kver); + + _debug("KEY I/F VERSION: %u", kver); + + ret = -EKEYREJECTED; + if (kver != 1) + goto error; + + /* deal with a version 1 key */ + ret = -EINVAL; + if (prep->datalen < sizeof(*v1)) + goto error; + + v1 = prep->data; + if (prep->datalen != sizeof(*v1) + v1->ticket_length) + goto error; + + _debug("SCIX: %u", v1->security_index); + _debug("TLEN: %u", v1->ticket_length); + _debug("EXPY: %x", v1->expiry); + _debug("KVNO: %u", v1->kvno); + _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x", + v1->session_key[0], v1->session_key[1], + v1->session_key[2], v1->session_key[3], + v1->session_key[4], v1->session_key[5], + v1->session_key[6], v1->session_key[7]); + if (v1->ticket_length >= 8) + _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x", + v1->ticket[0], v1->ticket[1], + v1->ticket[2], v1->ticket[3], + v1->ticket[4], v1->ticket[5], + v1->ticket[6], v1->ticket[7]); + + ret = -EPROTONOSUPPORT; + if (v1->security_index != RXRPC_SECURITY_RXKAD) + goto error; + + plen = sizeof(*token->kad) + v1->ticket_length; + prep->quotalen = plen + sizeof(*token); + + ret = -ENOMEM; + token = kzalloc(sizeof(*token), GFP_KERNEL); + if (!token) + goto error; + token->kad = kzalloc(plen, GFP_KERNEL); + if (!token->kad) + goto error_free; + + token->security_index = RXRPC_SECURITY_RXKAD; + token->kad->ticket_len = v1->ticket_length; + token->kad->expiry = v1->expiry; + token->kad->kvno = v1->kvno; + memcpy(&token->kad->session_key, &v1->session_key, 8); + memcpy(&token->kad->ticket, v1->ticket, v1->ticket_length); + + /* count the number of tokens attached */ + prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1); + + /* attach the data */ + pp = (struct rxrpc_key_token **)&prep->payload.data[0]; + while (*pp) + pp = &(*pp)->next; + *pp = token; + expiry = rxrpc_u32_to_time64(token->kad->expiry); + if (expiry < prep->expiry) + prep->expiry = expiry; + token = NULL; + ret = 0; + +error_free: + kfree(token); +error: + return ret; +} + +/* + * Free token list. + */ +static void rxrpc_free_token_list(struct rxrpc_key_token *token) +{ + struct rxrpc_key_token *next; + + for (; token; token = next) { + next = token->next; + switch (token->security_index) { + case RXRPC_SECURITY_RXKAD: + kfree(token->kad); + break; + default: + pr_err("Unknown token type %x on rxrpc key\n", + token->security_index); + BUG(); + } + + kfree(token); + } +} + +/* + * Clean up preparse data. + */ +static void rxrpc_free_preparse(struct key_preparsed_payload *prep) +{ + rxrpc_free_token_list(prep->payload.data[0]); +} + +/* + * dispose of the data dangling from the corpse of a rxrpc key + */ +static void rxrpc_destroy(struct key *key) +{ + rxrpc_free_token_list(key->payload.data[0]); +} + +/* + * describe the rxrpc key + */ +static void rxrpc_describe(const struct key *key, struct seq_file *m) +{ + const struct rxrpc_key_token *token; + const char *sep = ": "; + + seq_puts(m, key->description); + + for (token = key->payload.data[0]; token; token = token->next) { + seq_puts(m, sep); + + switch (token->security_index) { + case RXRPC_SECURITY_RXKAD: + seq_puts(m, "ka"); + break; + default: /* we have a ticket we can't encode */ + seq_printf(m, "%u", token->security_index); + break; + } + + sep = " "; + } +} + +/* + * grab the security key for a socket + */ +int rxrpc_request_key(struct rxrpc_sock *rx, sockptr_t optval, int optlen) +{ + struct key *key; + char *description; + + _enter(""); + + if (optlen <= 0 || optlen > PAGE_SIZE - 1 || rx->securities) + return -EINVAL; + + description = memdup_sockptr_nul(optval, optlen); + if (IS_ERR(description)) + return PTR_ERR(description); + + key = request_key_net(&key_type_rxrpc, description, sock_net(&rx->sk), NULL); + if (IS_ERR(key)) { + kfree(description); + _leave(" = %ld", PTR_ERR(key)); + return PTR_ERR(key); + } + + rx->key = key; + kfree(description); + _leave(" = 0 [key %x]", key->serial); + return 0; +} + +/* + * generate a server data key + */ +int rxrpc_get_server_data_key(struct rxrpc_connection *conn, + const void *session_key, + time64_t expiry, + u32 kvno) +{ + const struct cred *cred = current_cred(); + struct key *key; + int ret; + + struct { + u32 kver; + struct rxrpc_key_data_v1 v1; + } data; + + _enter(""); + + key = key_alloc(&key_type_rxrpc, "x", + GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, 0, + KEY_ALLOC_NOT_IN_QUOTA, NULL); + if (IS_ERR(key)) { + _leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key)); + return -ENOMEM; + } + + _debug("key %d", key_serial(key)); + + data.kver = 1; + data.v1.security_index = RXRPC_SECURITY_RXKAD; + data.v1.ticket_length = 0; + data.v1.expiry = rxrpc_time64_to_u32(expiry); + data.v1.kvno = 0; + + memcpy(&data.v1.session_key, session_key, sizeof(data.v1.session_key)); + + ret = key_instantiate_and_link(key, &data, sizeof(data), NULL, NULL); + if (ret < 0) + goto error; + + conn->params.key = key; + _leave(" = 0 [%d]", key_serial(key)); + return 0; + +error: + key_revoke(key); + key_put(key); + _leave(" = -ENOMEM [ins %d]", ret); + return -ENOMEM; +} +EXPORT_SYMBOL(rxrpc_get_server_data_key); + +/** + * rxrpc_get_null_key - Generate a null RxRPC key + * @keyname: The name to give the key. + * + * Generate a null RxRPC key that can be used to indicate anonymous security is + * required for a particular domain. + */ +struct key *rxrpc_get_null_key(const char *keyname) +{ + const struct cred *cred = current_cred(); + struct key *key; + int ret; + + key = key_alloc(&key_type_rxrpc, keyname, + GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, + KEY_POS_SEARCH, KEY_ALLOC_NOT_IN_QUOTA, NULL); + if (IS_ERR(key)) + return key; + + ret = key_instantiate_and_link(key, NULL, 0, NULL, NULL); + if (ret < 0) { + key_revoke(key); + key_put(key); + return ERR_PTR(ret); + } + + return key; +} +EXPORT_SYMBOL(rxrpc_get_null_key); + +/* + * read the contents of an rxrpc key + * - this returns the result in XDR form + */ +static long rxrpc_read(const struct key *key, + char *buffer, size_t buflen) +{ + const struct rxrpc_key_token *token; + size_t size; + __be32 *xdr, *oldxdr; + u32 cnlen, toksize, ntoks, tok, zero; + u16 toksizes[AFSTOKEN_MAX]; + + _enter(""); + + /* we don't know what form we should return non-AFS keys in */ + if (memcmp(key->description, "afs@", 4) != 0) + return -EOPNOTSUPP; + cnlen = strlen(key->description + 4); + +#define RND(X) (((X) + 3) & ~3) + + /* AFS keys we return in XDR form, so we need to work out the size of + * the XDR */ + size = 2 * 4; /* flags, cellname len */ + size += RND(cnlen); /* cellname */ + size += 1 * 4; /* token count */ + + ntoks = 0; + for (token = key->payload.data[0]; token; token = token->next) { + toksize = 4; /* sec index */ + + switch (token->security_index) { + case RXRPC_SECURITY_RXKAD: + toksize += 8 * 4; /* viceid, kvno, key*2, begin, + * end, primary, tktlen */ + if (!token->no_leak_key) + toksize += RND(token->kad->ticket_len); + break; + + default: /* we have a ticket we can't encode */ + pr_err("Unsupported key token type (%u)\n", + token->security_index); + return -ENOPKG; + } + + _debug("token[%u]: toksize=%u", ntoks, toksize); + ASSERTCMP(toksize, <=, AFSTOKEN_LENGTH_MAX); + + toksizes[ntoks++] = toksize; + size += toksize + 4; /* each token has a length word */ + } + +#undef RND + + if (!buffer || buflen < size) + return size; + + xdr = (__be32 *)buffer; + zero = 0; +#define ENCODE(x) \ + do { \ + *xdr++ = htonl(x); \ + } while(0) +#define ENCODE_DATA(l, s) \ + do { \ + u32 _l = (l); \ + ENCODE(l); \ + memcpy(xdr, (s), _l); \ + if (_l & 3) \ + memcpy((u8 *)xdr + _l, &zero, 4 - (_l & 3)); \ + xdr += (_l + 3) >> 2; \ + } while(0) +#define ENCODE_BYTES(l, s) \ + do { \ + u32 _l = (l); \ + memcpy(xdr, (s), _l); \ + if (_l & 3) \ + memcpy((u8 *)xdr + _l, &zero, 4 - (_l & 3)); \ + xdr += (_l + 3) >> 2; \ + } while(0) +#define ENCODE64(x) \ + do { \ + __be64 y = cpu_to_be64(x); \ + memcpy(xdr, &y, 8); \ + xdr += 8 >> 2; \ + } while(0) +#define ENCODE_STR(s) \ + do { \ + const char *_s = (s); \ + ENCODE_DATA(strlen(_s), _s); \ + } while(0) + + ENCODE(0); /* flags */ + ENCODE_DATA(cnlen, key->description + 4); /* cellname */ + ENCODE(ntoks); + + tok = 0; + for (token = key->payload.data[0]; token; token = token->next) { + toksize = toksizes[tok++]; + ENCODE(toksize); + oldxdr = xdr; + ENCODE(token->security_index); + + switch (token->security_index) { + case RXRPC_SECURITY_RXKAD: + ENCODE(token->kad->vice_id); + ENCODE(token->kad->kvno); + ENCODE_BYTES(8, token->kad->session_key); + ENCODE(token->kad->start); + ENCODE(token->kad->expiry); + ENCODE(token->kad->primary_flag); + if (token->no_leak_key) + ENCODE(0); + else + ENCODE_DATA(token->kad->ticket_len, token->kad->ticket); + break; + + default: + pr_err("Unsupported key token type (%u)\n", + token->security_index); + return -ENOPKG; + } + + ASSERTCMP((unsigned long)xdr - (unsigned long)oldxdr, ==, + toksize); + } + +#undef ENCODE_STR +#undef ENCODE_DATA +#undef ENCODE64 +#undef ENCODE + + ASSERTCMP(tok, ==, ntoks); + ASSERTCMP((char __user *) xdr - buffer, ==, size); + _leave(" = %zu", size); + return size; +} -- cgit v1.2.3