diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-10-12 10:13:55 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-10-12 10:13:55 -0400 |
commit | 5e40d331bd72447197f26525f21711c4a265b6a6 (patch) | |
tree | cfbf5efba46b0c5c5b3c8149395f721eab839945 /crypto/asymmetric_keys | |
parent | d0ca47575ab3b41bb7f0fe5feec13c6cddb2913a (diff) | |
parent | 594081ee7145cc30a3977cb4e218f81213b63dc5 (diff) |
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris.
Mostly ima, selinux, smack and key handling updates.
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (65 commits)
integrity: do zero padding of the key id
KEYS: output last portion of fingerprint in /proc/keys
KEYS: strip 'id:' from ca_keyid
KEYS: use swapped SKID for performing partial matching
KEYS: Restore partial ID matching functionality for asymmetric keys
X.509: If available, use the raw subjKeyId to form the key description
KEYS: handle error code encoded in pointer
selinux: normalize audit log formatting
selinux: cleanup error reporting in selinux_nlmsg_perm()
KEYS: Check hex2bin()'s return when generating an asymmetric key ID
ima: detect violations for mmaped files
ima: fix race condition on ima_rdwr_violation_check and process_measurement
ima: added ima_policy_flag variable
ima: return an error code from ima_add_boot_aggregate()
ima: provide 'ima_appraise=log' kernel option
ima: move keyring initialization to ima_init()
PKCS#7: Handle PKCS#7 messages that contain no X.509 certs
PKCS#7: Better handling of unsupported crypto
KEYS: Overhaul key identification when searching for asymmetric keys
KEYS: Implement binary asymmetric key ID handling
...
Diffstat (limited to 'crypto/asymmetric_keys')
-rw-r--r-- | crypto/asymmetric_keys/asymmetric_keys.h | 5 | ||||
-rw-r--r-- | crypto/asymmetric_keys/asymmetric_type.c | 265 | ||||
-rw-r--r-- | crypto/asymmetric_keys/pkcs7_key_type.c | 2 | ||||
-rw-r--r-- | crypto/asymmetric_keys/pkcs7_parser.c | 99 | ||||
-rw-r--r-- | crypto/asymmetric_keys/pkcs7_parser.h | 6 | ||||
-rw-r--r-- | crypto/asymmetric_keys/pkcs7_trust.c | 90 | ||||
-rw-r--r-- | crypto/asymmetric_keys/pkcs7_verify.c | 102 | ||||
-rw-r--r-- | crypto/asymmetric_keys/signature.c | 1 | ||||
-rw-r--r-- | crypto/asymmetric_keys/x509_cert_parser.c | 57 | ||||
-rw-r--r-- | crypto/asymmetric_keys/x509_parser.h | 8 | ||||
-rw-r--r-- | crypto/asymmetric_keys/x509_public_key.c | 115 |
11 files changed, 518 insertions, 232 deletions
diff --git a/crypto/asymmetric_keys/asymmetric_keys.h b/crypto/asymmetric_keys/asymmetric_keys.h index a63c551c6557..f97330886d58 100644 --- a/crypto/asymmetric_keys/asymmetric_keys.h +++ b/crypto/asymmetric_keys/asymmetric_keys.h @@ -9,9 +9,10 @@ * 2 of the Licence, or (at your option) any later version. */ -int asymmetric_keyid_match(const char *kid, const char *id); +extern struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id); -static inline const char *asymmetric_key_id(const struct key *key) +static inline +const struct asymmetric_key_ids *asymmetric_key_ids(const struct key *key) { return key->type_data.p[1]; } diff --git a/crypto/asymmetric_keys/asymmetric_type.c b/crypto/asymmetric_keys/asymmetric_type.c index eb8cd46961a5..bcbbbd794e1d 100644 --- a/crypto/asymmetric_keys/asymmetric_type.c +++ b/crypto/asymmetric_keys/asymmetric_type.c @@ -15,6 +15,7 @@ #include <linux/seq_file.h> #include <linux/module.h> #include <linux/slab.h> +#include <linux/ctype.h> #include "asymmetric_keys.h" MODULE_LICENSE("GPL"); @@ -22,85 +23,209 @@ MODULE_LICENSE("GPL"); static LIST_HEAD(asymmetric_key_parsers); static DECLARE_RWSEM(asymmetric_key_parsers_sem); -/* - * Match asymmetric key id with partial match - * @id: key id to match in a form "id:<id>" +/** + * asymmetric_key_generate_id: Construct an asymmetric key ID + * @val_1: First binary blob + * @len_1: Length of first binary blob + * @val_2: Second binary blob + * @len_2: Length of second binary blob + * + * Construct an asymmetric key ID from a pair of binary blobs. */ -int asymmetric_keyid_match(const char *kid, const char *id) +struct asymmetric_key_id *asymmetric_key_generate_id(const void *val_1, + size_t len_1, + const void *val_2, + size_t len_2) { - size_t idlen, kidlen; + struct asymmetric_key_id *kid; + + kid = kmalloc(sizeof(struct asymmetric_key_id) + len_1 + len_2, + GFP_KERNEL); + if (!kid) + return ERR_PTR(-ENOMEM); + kid->len = len_1 + len_2; + memcpy(kid->data, val_1, len_1); + memcpy(kid->data + len_1, val_2, len_2); + return kid; +} +EXPORT_SYMBOL_GPL(asymmetric_key_generate_id); - if (!kid || !id) - return 0; +/** + * asymmetric_key_id_same - Return true if two asymmetric keys IDs are the same. + * @kid_1, @kid_2: The key IDs to compare + */ +bool asymmetric_key_id_same(const struct asymmetric_key_id *kid1, + const struct asymmetric_key_id *kid2) +{ + if (!kid1 || !kid2) + return false; + if (kid1->len != kid2->len) + return false; + return memcmp(kid1->data, kid2->data, kid1->len) == 0; +} +EXPORT_SYMBOL_GPL(asymmetric_key_id_same); - /* make it possible to use id as in the request: "id:<id>" */ - if (strncmp(id, "id:", 3) == 0) - id += 3; +/** + * asymmetric_key_id_partial - Return true if two asymmetric keys IDs + * partially match + * @kid_1, @kid_2: The key IDs to compare + */ +bool asymmetric_key_id_partial(const struct asymmetric_key_id *kid1, + const struct asymmetric_key_id *kid2) +{ + if (!kid1 || !kid2) + return false; + if (kid1->len < kid2->len) + return false; + return memcmp(kid1->data + (kid1->len - kid2->len), + kid2->data, kid2->len) == 0; +} +EXPORT_SYMBOL_GPL(asymmetric_key_id_partial); - /* Anything after here requires a partial match on the ID string */ - idlen = strlen(id); - kidlen = strlen(kid); - if (idlen > kidlen) - return 0; +/** + * asymmetric_match_key_ids - Search asymmetric key IDs + * @kids: The list of key IDs to check + * @match_id: The key ID we're looking for + * @match: The match function to use + */ +static bool asymmetric_match_key_ids( + const struct asymmetric_key_ids *kids, + const struct asymmetric_key_id *match_id, + bool (*match)(const struct asymmetric_key_id *kid1, + const struct asymmetric_key_id *kid2)) +{ + int i; + + if (!kids || !match_id) + return false; + for (i = 0; i < ARRAY_SIZE(kids->id); i++) + if (match(kids->id[i], match_id)) + return true; + return false; +} - kid += kidlen - idlen; - if (strcasecmp(id, kid) != 0) - return 0; +/** + * asymmetric_key_hex_to_key_id - Convert a hex string into a key ID. + * @id: The ID as a hex string. + */ +struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id) +{ + struct asymmetric_key_id *match_id; + size_t hexlen; + int ret; - return 1; + if (!*id) + return ERR_PTR(-EINVAL); + hexlen = strlen(id); + if (hexlen & 1) + return ERR_PTR(-EINVAL); + + match_id = kmalloc(sizeof(struct asymmetric_key_id) + hexlen / 2, + GFP_KERNEL); + if (!match_id) + return ERR_PTR(-ENOMEM); + match_id->len = hexlen / 2; + ret = hex2bin(match_id->data, id, hexlen / 2); + if (ret < 0) { + kfree(match_id); + return ERR_PTR(-EINVAL); + } + return match_id; } -EXPORT_SYMBOL_GPL(asymmetric_keyid_match); /* - * Match asymmetric keys on (part of) their name - * We have some shorthand methods for matching keys. We allow: - * - * "<desc>" - request a key by description - * "id:<id>" - request a key matching the ID - * "<subtype>:<id>" - request a key of a subtype + * Match asymmetric keys by an exact match on an ID. */ -static int asymmetric_key_match(const struct key *key, const void *description) +static bool asymmetric_key_cmp(const struct key *key, + const struct key_match_data *match_data) { - const struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key); - const char *spec = description; - const char *id; - ptrdiff_t speclen; + const struct asymmetric_key_ids *kids = asymmetric_key_ids(key); + const struct asymmetric_key_id *match_id = match_data->preparsed; - if (!subtype || !spec || !*spec) - return 0; + return asymmetric_match_key_ids(kids, match_id, + asymmetric_key_id_same); +} - /* See if the full key description matches as is */ - if (key->description && strcmp(key->description, description) == 0) - return 1; +/* + * Match asymmetric keys by a partial match on an IDs. + */ +static bool asymmetric_key_cmp_partial(const struct key *key, + const struct key_match_data *match_data) +{ + const struct asymmetric_key_ids *kids = asymmetric_key_ids(key); + const struct asymmetric_key_id *match_id = match_data->preparsed; - /* All tests from here on break the criterion description into a - * specifier, a colon and then an identifier. - */ - id = strchr(spec, ':'); - if (!id) - return 0; + return asymmetric_match_key_ids(kids, match_id, + asymmetric_key_id_partial); +} + +/* + * Preparse the match criterion. If we don't set lookup_type and cmp, + * the default will be an exact match on the key description. + * + * There are some specifiers for matching key IDs rather than by the key + * description: + * + * "id:<id>" - find a key by partial match on any available ID + * "ex:<id>" - find a key by exact match on any available ID + * + * These have to be searched by iteration rather than by direct lookup because + * the key is hashed according to its description. + */ +static int asymmetric_key_match_preparse(struct key_match_data *match_data) +{ + struct asymmetric_key_id *match_id; + const char *spec = match_data->raw_data; + const char *id; + bool (*cmp)(const struct key *, const struct key_match_data *) = + asymmetric_key_cmp; - speclen = id - spec; - id++; + if (!spec || !*spec) + return -EINVAL; + if (spec[0] == 'i' && + spec[1] == 'd' && + spec[2] == ':') { + id = spec + 3; + cmp = asymmetric_key_cmp_partial; + } else if (spec[0] == 'e' && + spec[1] == 'x' && + spec[2] == ':') { + id = spec + 3; + } else { + goto default_match; + } - if (speclen == 2 && memcmp(spec, "id", 2) == 0) - return asymmetric_keyid_match(asymmetric_key_id(key), id); + match_id = asymmetric_key_hex_to_key_id(id); + if (IS_ERR(match_id)) + return PTR_ERR(match_id); - if (speclen == subtype->name_len && - memcmp(spec, subtype->name, speclen) == 0) - return 1; + match_data->preparsed = match_id; + match_data->cmp = cmp; + match_data->lookup_type = KEYRING_SEARCH_LOOKUP_ITERATE; + return 0; +default_match: return 0; } /* + * Free the preparsed the match criterion. + */ +static void asymmetric_key_match_free(struct key_match_data *match_data) +{ + kfree(match_data->preparsed); +} + +/* * Describe the asymmetric key */ static void asymmetric_key_describe(const struct key *key, struct seq_file *m) { const struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key); - const char *kid = asymmetric_key_id(key); - size_t n; + const struct asymmetric_key_ids *kids = asymmetric_key_ids(key); + const struct asymmetric_key_id *kid; + const unsigned char *p; + int n; seq_puts(m, key->description); @@ -108,13 +233,16 @@ static void asymmetric_key_describe(const struct key *key, struct seq_file *m) seq_puts(m, ": "); subtype->describe(key, m); - if (kid) { + if (kids && kids->id[1]) { + kid = kids->id[1]; seq_putc(m, ' '); - n = strlen(kid); - if (n <= 8) - seq_puts(m, kid); - else - seq_puts(m, kid + n - 8); + n = kid->len; + p = kid->data; + if (n > 4) { + p += n - 4; + n = 4; + } + seq_printf(m, "%*phN", n, p); } seq_puts(m, " ["); @@ -165,6 +293,8 @@ static int asymmetric_key_preparse(struct key_preparsed_payload *prep) static void asymmetric_key_free_preparse(struct key_preparsed_payload *prep) { struct asymmetric_key_subtype *subtype = prep->type_data[0]; + struct asymmetric_key_ids *kids = prep->type_data[1]; + int i; pr_devel("==>%s()\n", __func__); @@ -172,7 +302,11 @@ static void asymmetric_key_free_preparse(struct key_preparsed_payload *prep) subtype->destroy(prep->payload[0]); module_put(subtype->owner); } - kfree(prep->type_data[1]); + if (kids) { + for (i = 0; i < ARRAY_SIZE(kids->id); i++) + kfree(kids->id[i]); + kfree(kids); + } kfree(prep->description); } @@ -182,13 +316,20 @@ static void asymmetric_key_free_preparse(struct key_preparsed_payload *prep) static void asymmetric_key_destroy(struct key *key) { struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key); + struct asymmetric_key_ids *kids = key->type_data.p[1]; + if (subtype) { subtype->destroy(key->payload.data); module_put(subtype->owner); key->type_data.p[0] = NULL; } - kfree(key->type_data.p[1]); - key->type_data.p[1] = NULL; + + if (kids) { + kfree(kids->id[0]); + kfree(kids->id[1]); + kfree(kids); + key->type_data.p[1] = NULL; + } } struct key_type key_type_asymmetric = { @@ -196,10 +337,10 @@ struct key_type key_type_asymmetric = { .preparse = asymmetric_key_preparse, .free_preparse = asymmetric_key_free_preparse, .instantiate = generic_key_instantiate, - .match = asymmetric_key_match, + .match_preparse = asymmetric_key_match_preparse, + .match_free = asymmetric_key_match_free, .destroy = asymmetric_key_destroy, .describe = asymmetric_key_describe, - .def_lookup_type = KEYRING_SEARCH_LOOKUP_ITERATE, }; EXPORT_SYMBOL_GPL(key_type_asymmetric); diff --git a/crypto/asymmetric_keys/pkcs7_key_type.c b/crypto/asymmetric_keys/pkcs7_key_type.c index 3de5fb011de0..751f8fd7335d 100644 --- a/crypto/asymmetric_keys/pkcs7_key_type.c +++ b/crypto/asymmetric_keys/pkcs7_key_type.c @@ -72,11 +72,9 @@ error: */ static struct key_type key_type_pkcs7 = { .name = "pkcs7_test", - .def_lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT, .preparse = pkcs7_preparse, .free_preparse = user_free_preparse, .instantiate = generic_key_instantiate, - .match = user_match, .revoke = user_revoke, .destroy = user_destroy, .describe = user_describe, diff --git a/crypto/asymmetric_keys/pkcs7_parser.c b/crypto/asymmetric_keys/pkcs7_parser.c index 42e56aa7d277..3bd5a1e4c493 100644 --- a/crypto/asymmetric_keys/pkcs7_parser.c +++ b/crypto/asymmetric_keys/pkcs7_parser.c @@ -29,8 +29,25 @@ struct pkcs7_parse_context { enum OID last_oid; /* Last OID encountered */ unsigned x509_index; unsigned sinfo_index; + const void *raw_serial; + unsigned raw_serial_size; + unsigned raw_issuer_size; + const void *raw_issuer; }; +/* + * Free a signed information block. + */ +static void pkcs7_free_signed_info(struct pkcs7_signed_info *sinfo) +{ + if (sinfo) { + mpi_free(sinfo->sig.mpi[0]); + kfree(sinfo->sig.digest); + kfree(sinfo->signing_cert_id); + kfree(sinfo); + } +} + /** * pkcs7_free_message - Free a PKCS#7 message * @pkcs7: The PKCS#7 message to free @@ -54,9 +71,7 @@ void pkcs7_free_message(struct pkcs7_message *pkcs7) while (pkcs7->signed_infos) { sinfo = pkcs7->signed_infos; pkcs7->signed_infos = sinfo->next; - mpi_free(sinfo->sig.mpi[0]); - kfree(sinfo->sig.digest); - kfree(sinfo); + pkcs7_free_signed_info(sinfo); } kfree(pkcs7); } @@ -71,51 +86,46 @@ EXPORT_SYMBOL_GPL(pkcs7_free_message); struct pkcs7_message *pkcs7_parse_message(const void *data, size_t datalen) { struct pkcs7_parse_context *ctx; - struct pkcs7_message *msg; - long ret; + struct pkcs7_message *msg = ERR_PTR(-ENOMEM); + int ret; - ret = -ENOMEM; - msg = kzalloc(sizeof(struct pkcs7_message), GFP_KERNEL); - if (!msg) - goto error_no_sig; ctx = kzalloc(sizeof(struct pkcs7_parse_context), GFP_KERNEL); if (!ctx) - goto error_no_ctx; + goto out_no_ctx; + ctx->msg = kzalloc(sizeof(struct pkcs7_message), GFP_KERNEL); + if (!ctx->msg) + goto out_no_msg; ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL); if (!ctx->sinfo) - goto error_no_sinfo; + goto out_no_sinfo; - ctx->msg = msg; ctx->data = (unsigned long)data; ctx->ppcerts = &ctx->certs; ctx->ppsinfo = &ctx->msg->signed_infos; /* Attempt to decode the signature */ ret = asn1_ber_decoder(&pkcs7_decoder, ctx, data, datalen); - if (ret < 0) - goto error_decode; + if (ret < 0) { + msg = ERR_PTR(ret); + goto out; + } + msg = ctx->msg; + ctx->msg = NULL; + +out: while (ctx->certs) { struct x509_certificate *cert = ctx->certs; ctx->certs = cert->next; x509_free_certificate(cert); } - mpi_free(ctx->sinfo->sig.mpi[0]); - kfree(ctx->sinfo->sig.digest); - kfree(ctx->sinfo); + pkcs7_free_signed_info(ctx->sinfo); +out_no_sinfo: + pkcs7_free_message(ctx->msg); +out_no_msg: kfree(ctx); +out_no_ctx: return msg; - -error_decode: - mpi_free(ctx->sinfo->sig.mpi[0]); - kfree(ctx->sinfo->sig.digest); - kfree(ctx->sinfo); -error_no_sinfo: - kfree(ctx); -error_no_ctx: - pkcs7_free_message(msg); -error_no_sig: - return ERR_PTR(ret); } EXPORT_SYMBOL_GPL(pkcs7_parse_message); @@ -246,10 +256,10 @@ int pkcs7_extract_cert(void *context, size_t hdrlen, if (IS_ERR(x509)) return PTR_ERR(x509); - pr_debug("Got cert for %s\n", x509->subject); - pr_debug("- fingerprint %s\n", x509->fingerprint); - x509->index = ++ctx->x509_index; + pr_debug("Got cert %u for %s\n", x509->index, x509->subject); + pr_debug("- fingerprint %*phN\n", x509->id->len, x509->id->data); + *ctx->ppcerts = x509; ctx->ppcerts = &x509->next; return 0; @@ -338,8 +348,8 @@ int pkcs7_sig_note_serial(void *context, size_t hdrlen, const void *value, size_t vlen) { struct pkcs7_parse_context *ctx = context; - ctx->sinfo->raw_serial = value; - ctx->sinfo->raw_serial_size = vlen; + ctx->raw_serial = value; + ctx->raw_serial_size = vlen; return 0; } @@ -351,8 +361,8 @@ int pkcs7_sig_note_issuer(void *context, size_t hdrlen, const void *value, size_t vlen) { struct pkcs7_parse_context *ctx = context; - ctx->sinfo->raw_issuer = value; - ctx->sinfo->raw_issuer_size = vlen; + ctx->raw_issuer = value; + ctx->raw_issuer_size = vlen; return 0; } @@ -385,10 +395,21 @@ int pkcs7_note_signed_info(void *context, size_t hdrlen, const void *value, size_t vlen) { struct pkcs7_parse_context *ctx = context; - - ctx->sinfo->index = ++ctx->sinfo_index; - *ctx->ppsinfo = ctx->sinfo; - ctx->ppsinfo = &ctx->sinfo->next; + struct pkcs7_signed_info *sinfo = ctx->sinfo; + struct asymmetric_key_id *kid; + + /* Generate cert issuer + serial number key ID */ + kid = asymmetric_key_generate_id(ctx->raw_serial, + ctx->raw_serial_size, + ctx->raw_issuer, + ctx->raw_issuer_size); + if (IS_ERR(kid)) + return PTR_ERR(kid); + + sinfo->signing_cert_id = kid; + sinfo->index = ++ctx->sinfo_index; + *ctx->ppsinfo = sinfo; + ctx->ppsinfo = &sinfo->next; ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL); if (!ctx->sinfo) return -ENOMEM; diff --git a/crypto/asymmetric_keys/pkcs7_parser.h b/crypto/asymmetric_keys/pkcs7_parser.h index d25f4d15370f..efc7dc9b8f9c 100644 --- a/crypto/asymmetric_keys/pkcs7_parser.h +++ b/crypto/asymmetric_keys/pkcs7_parser.h @@ -23,6 +23,7 @@ struct pkcs7_signed_info { struct x509_certificate *signer; /* Signing certificate (in msg->certs) */ unsigned index; bool trusted; + bool unsupported_crypto; /* T if not usable due to missing crypto */ /* Message digest - the digest of the Content Data (or NULL) */ const void *msgdigest; @@ -33,10 +34,7 @@ struct pkcs7_signed_info { const void *authattrs; /* Issuing cert serial number and issuer's name */ - const void *raw_serial; - unsigned raw_serial_size; - unsigned raw_issuer_size; - const void *raw_issuer; + struct asymmetric_key_id *signing_cert_id; /* Message signature. * diff --git a/crypto/asymmetric_keys/pkcs7_trust.c b/crypto/asymmetric_keys/pkcs7_trust.c index e666eb011a85..1d29376072da 100644 --- a/crypto/asymmetric_keys/pkcs7_trust.c +++ b/crypto/asymmetric_keys/pkcs7_trust.c @@ -23,9 +23,9 @@ /** * Check the trust on one PKCS#7 SignedInfo block. */ -int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7, - struct pkcs7_signed_info *sinfo, - struct key *trust_keyring) +static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7, + struct pkcs7_signed_info *sinfo, + struct key *trust_keyring) { struct public_key_signature *sig = &sinfo->sig; struct x509_certificate *x509, *last = NULL, *p; @@ -35,6 +35,11 @@ int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7, kenter(",%u,", sinfo->index); + if (sinfo->unsupported_crypto) { + kleave(" = -ENOPKG [cached]"); + return -ENOPKG; + } + for (x509 = sinfo->signer; x509; x509 = x509->signer) { if (x509->seen) { if (x509->verified) { @@ -49,15 +54,18 @@ int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7, /* Look to see if this certificate is present in the trusted * keys. */ - key = x509_request_asymmetric_key(trust_keyring, x509->subject, - x509->fingerprint); - if (!IS_ERR(key)) + key = x509_request_asymmetric_key(trust_keyring, x509->id, + false); + if (!IS_ERR(key)) { /* One of the X.509 certificates in the PKCS#7 message * is apparently the same as one we already trust. * Verify that the trusted variant can also validate * the signature on the descendant. */ + pr_devel("sinfo %u: Cert %u as key %x\n", + sinfo->index, x509->index, key_serial(key)); goto matched; + } if (key == ERR_PTR(-ENOMEM)) return -ENOMEM; @@ -77,16 +85,36 @@ int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7, /* No match - see if the root certificate has a signer amongst the * trusted keys. */ - if (!last || !last->issuer || !last->authority) { - kleave(" = -ENOKEY [no backref]"); - return -ENOKEY; + if (last && last->authority) { + key = x509_request_asymmetric_key(trust_keyring, last->authority, + false); + if (!IS_ERR(key)) { + x509 = last; + pr_devel("sinfo %u: Root cert %u signer is key %x\n", + sinfo->index, x509->index, key_serial(key)); + goto matched; + } + if (PTR_ERR(key) != -ENOKEY) + return PTR_ERR(key); + } + + /* As a last resort, see if we have a trusted public key that matches + * the signed info directly. + */ + key = x509_request_asymmetric_key(trust_keyring, + sinfo->signing_cert_id, + false); + if (!IS_ERR(key)) { + pr_devel("sinfo %u: Direct signer is key %x\n", + sinfo->index, key_serial(key)); + x509 = NULL; + goto matched; } + if (PTR_ERR(key) != -ENOKEY) + return PTR_ERR(key); - key = x509_request_asymmetric_key(trust_keyring, last->issuer, - last->authority); - if (IS_ERR(key)) - return PTR_ERR(key) == -ENOMEM ? -ENOMEM : -ENOKEY; - x509 = last; + kleave(" = -ENOKEY [no backref]"); + return -ENOKEY; matched: ret = verify_signature(key, sig); @@ -100,10 +128,12 @@ matched: } verified: - x509->verified = true; - for (p = sinfo->signer; p != x509; p = p->signer) { - p->verified = true; - p->trusted = trusted; + if (x509) { + x509->verified = true; + for (p = sinfo->signer; p != x509; p = p->signer) { + p->verified = true; + p->trusted = trusted; + } } sinfo->trusted = trusted; kleave(" = 0"); @@ -141,24 +171,28 @@ int pkcs7_validate_trust(struct pkcs7_message *pkcs7, { struct pkcs7_signed_info *sinfo; struct x509_certificate *p; - int cached_ret = 0, ret; + int cached_ret = -ENOKEY; + int ret; for (p = pkcs7->certs; p; p = p->next) p->seen = false; for (sinfo = pkcs7->signed_infos; sinfo; sinfo = sinfo->next) { ret = pkcs7_validate_trust_one(pkcs7, sinfo, trust_keyring); - if (ret < 0) { - if (ret == -ENOPKG) { + switch (ret) { + case -ENOKEY: + continue; + case -ENOPKG: + if (cached_ret == -ENOKEY) cached_ret = -ENOPKG; - } else if (ret == -ENOKEY) { - if (cached_ret == 0) - cached_ret = -ENOKEY; - } else { - return ret; - } + continue; + case 0: + *_trusted |= sinfo->trusted; + cached_ret = 0; + continue; + default: + return ret; } - *_trusted |= sinfo->trusted; } return cached_ret; diff --git a/crypto/asymmetric_keys/pkcs7_verify.c b/crypto/asymmetric_keys/pkcs7_verify.c index c62cf8006e1f..cd455450b069 100644 --- a/crypto/asymmetric_keys/pkcs7_verify.c +++ b/crypto/asymmetric_keys/pkcs7_verify.c @@ -131,8 +131,7 @@ static int pkcs7_find_key(struct pkcs7_message *pkcs7, struct x509_certificate *x509; unsigned certix = 1; - kenter("%u,%u,%u", - sinfo->index, sinfo->raw_serial_size, sinfo->raw_issuer_size); + kenter("%u", sinfo->index); for (x509 = pkcs7->certs; x509; x509 = x509->next, certix++) { /* I'm _assuming_ that the generator of the PKCS#7 message will @@ -140,21 +139,11 @@ static int pkcs7_find_key(struct pkcs7_message *pkcs7, * PKCS#7 message - but I can't be 100% sure of that. It's * possible this will need element-by-element comparison. */ - if (x509->raw_serial_size != sinfo->raw_serial_size || - memcmp(x509->raw_serial, sinfo->raw_serial, - sinfo->raw_serial_size) != 0) + if (!asymmetric_key_id_same(x509->id, sinfo->signing_cert_id)) continue; pr_devel("Sig %u: Found cert serial match X.509[%u]\n", sinfo->index, certix); - if (x509->raw_issuer_size != sinfo->raw_issuer_size || - memcmp(x509->raw_issuer, sinfo->raw_issuer, - sinfo->raw_issuer_size) != 0) { - pr_warn("Sig %u: X.509 subject and PKCS#7 issuer don't match\n", - sinfo->index); - continue; - } - if (x509->pub->pkey_algo != sinfo->sig.pkey_algo) { pr_warn("Sig %u: X.509 algo and PKCS#7 sig algo don't match\n", sinfo->index); @@ -164,9 +153,14 @@ static int pkcs7_find_key(struct pkcs7_message *pkcs7, sinfo->signer = x509; return 0; } - pr_warn("Sig %u: Issuing X.509 cert not found (#%*ph)\n", - sinfo->index, sinfo->raw_serial_size, sinfo->raw_serial); - return -ENOKEY; + + /* The relevant X.509 cert isn't found here, but it might be found in + * the trust keyring. + */ + pr_debug("Sig %u: Issuing X.509 cert not found (#%*phN)\n", + sinfo->index, + sinfo->signing_cert_id->len, sinfo->signing_cert_id->data); + return 0; } /* @@ -184,15 +178,18 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7, p->seen = false; for (;;) { - pr_debug("verify %s: %s\n", x509->subject, x509->fingerprint); + pr_debug("verify %s: %*phN\n", + x509->subject, + x509->raw_serial_size, x509->raw_serial); x509->seen = true; ret = x509_get_sig_params(x509); if (ret < 0) - return ret; + goto maybe_missing_crypto_in_x509; pr_debug("- issuer %s\n", x509->issuer); if (x509->authority) - pr_debug("- authkeyid %s\n", x509->authority); + pr_debug("- authkeyid %*phN\n", + x509->authority->len, x509->authority->data); if (!x509->authority || strcmp(x509->subject, x509->issuer) == 0) { @@ -209,7 +206,7 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7, ret = x509_check_signature(x509->pub, x509); if (ret < 0) - return ret; + goto maybe_missing_crypto_in_x509; x509->signer = x509; pr_debug("- self-signed\n"); return 0; @@ -218,13 +215,14 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7, /* Look through the X.509 certificates in the PKCS#7 message's * list to see if the next one is there. */ - pr_debug("- want %s\n", x509->authority); + pr_debug("- want %*phN\n", + x509->authority->len, x509->authority->data); for (p = pkcs7->certs; p; p = p->next) { - pr_debug("- cmp [%u] %s\n", p->index, p->fingerprint); - if (p->raw_subject_size == x509->raw_issuer_size && - strcmp(p->fingerprint, x509->authority) == 0 && - memcmp(p->raw_subject, x509->raw_issuer, - x509->raw_issuer_size) == 0) + if (!p->skid) + continue; + pr_debug("- cmp [%u] %*phN\n", + p->index, p->skid->len, p->skid->data); + if (asymmetric_key_id_same(p->skid, x509->authority)) goto found_issuer; } @@ -233,7 +231,7 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7, return 0; found_issuer: - pr_debug("- issuer %s\n", p->subject); + pr_debug("- subject %s\n", p->subject); if (p->seen) { pr_warn("Sig %u: X.509 chain contains loop\n", sinfo->index); @@ -250,6 +248,17 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7, x509 = p; might_sleep(); } + +maybe_missing_crypto_in_x509: + /* Just prune the certificate chain at this point if we lack some + * crypto module to go further. Note, however, we don't want to set + * sinfo->missing_crypto as the signed info block may still be + * validatable against an X.509 cert lower in the chain that we have a + * trusted copy of. + */ + if (ret == -ENOPKG) + return 0; + return ret; } /* @@ -269,11 +278,14 @@ static int pkcs7_verify_one(struct pkcs7_message *pkcs7, if (ret < 0) return ret; - /* Find the key for the signature */ + /* Find the key for the signature if there is one */ ret = pkcs7_find_key(pkcs7, sinfo); if (ret < 0) return ret; + if (!sinfo->signer) + return 0; + pr_devel("Using X.509[%u] for sig %u\n", sinfo->signer->index, sinfo->index); @@ -291,11 +303,33 @@ static int pkcs7_verify_one(struct pkcs7_message *pkcs7, /** * pkcs7_verify - Verify a PKCS#7 message * @pkcs7: The PKCS#7 message to be verified + * + * Verify a PKCS#7 message is internally consistent - that is, the data digest + * matches the digest in the AuthAttrs and any signature in the message or one + * of the X.509 certificates it carries that matches another X.509 cert in the + * message can be verified. + * + * This does not look to match the contents of the PKCS#7 message against any + * external public keys. + * + * Returns, in order of descending priority: + * + * (*) -EKEYREJECTED if a signature failed to match for which we found an + * appropriate X.509 certificate, or: + * + * (*) -EBADMSG if some part of the message was invalid, or: + * + * (*) -ENOPKG if none of the signature chains are verifiable because suitable + * crypto modules couldn't be found, or: + * + * (*) 0 if all the signature chains that don't incur -ENOPKG can be verified + * (note that a signature chain may be of zero length), or: */ int pkcs7_verify(struct pkcs7_message *pkcs7) { struct pkcs7_signed_info *sinfo; struct x509_certificate *x509; + int enopkg = -ENOPKG; int ret, n; kenter(""); @@ -304,18 +338,24 @@ int pkcs7_verify(struct pkcs7_message *pkcs7) ret = x509_get_sig_params(x509); if (ret < 0) return ret; - pr_debug("X.509[%u] %s\n", n, x509->authority); + pr_debug("X.509[%u] %*phN\n", + n, x509->authority->len, x509->authority->data); } for (sinfo = pkcs7->signed_infos; sinfo; sinfo = sinfo->next) { ret = pkcs7_verify_one(pkcs7, sinfo); if (ret < 0) { + if (ret == -ENOPKG) { + sinfo->unsupported_crypto = true; + continue; + } kleave(" = %d", ret); return ret; } + enopkg = 0; } - kleave(" = 0"); - return 0; + kleave(" = %d", enopkg); + return enopkg; } EXPORT_SYMBOL_GPL(pkcs7_verify); diff --git a/crypto/asymmetric_keys/signature.c b/crypto/asymmetric_keys/signature.c index 50b3f880b4ff..7525fd183574 100644 --- a/crypto/asymmetric_keys/signature.c +++ b/crypto/asymmetric_keys/signature.c @@ -11,6 +11,7 @@ * 2 of the Licence, or (at your option) any later version. */ +#define pr_fmt(fmt) "SIG: "fmt #include <keys/asymmetric-subtype.h> #include <linux/module.h> #include <linux/err.h> diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c index ac72348c186a..a668d90302d3 100644 --- a/crypto/asymmetric_keys/x509_cert_parser.c +++ b/crypto/asymmetric_key |