From 4a38e122e2cc6294779021ff4ccc784a3997059e Mon Sep 17 00:00:00 2001 From: David Howells Date: Tue, 29 Apr 2008 01:01:24 -0700 Subject: keys: allow the callout data to be passed as a blob rather than a string Allow the callout data to be passed as a blob rather than a string for internal kernel services that call any request_key_*() interface other than request_key(). request_key() itself still takes a NUL-terminated string. The functions that change are: request_key_with_auxdata() request_key_async() request_key_async_with_auxdata() Signed-off-by: David Howells Cc: Paul Moore Cc: Chris Wright Cc: Stephen Smalley Cc: James Morris Cc: Kevin Coffman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/keys-request-key.txt | 11 +++++---- Documentation/keys.txt | 14 +++++++---- include/linux/key.h | 9 ++++--- security/keys/internal.h | 9 ++++--- security/keys/keyctl.c | 7 ++++-- security/keys/request_key.c | 49 +++++++++++++++++++++++--------------- security/keys/request_key_auth.c | 12 ++++++---- 7 files changed, 70 insertions(+), 41 deletions(-) diff --git a/Documentation/keys-request-key.txt b/Documentation/keys-request-key.txt index 266955d..09b55e4 100644 --- a/Documentation/keys-request-key.txt +++ b/Documentation/keys-request-key.txt @@ -11,26 +11,29 @@ request_key*(): struct key *request_key(const struct key_type *type, const char *description, - const char *callout_string); + const char *callout_info); or: struct key *request_key_with_auxdata(const struct key_type *type, const char *description, - const char *callout_string, + const char *callout_info, + size_t callout_len, void *aux); or: struct key *request_key_async(const struct key_type *type, const char *description, - const char *callout_string); + const char *callout_info, + size_t callout_len); or: struct key *request_key_async_with_auxdata(const struct key_type *type, const char *description, - const char *callout_string, + const char *callout_info, + size_t callout_len, void *aux); Or by userspace invoking the request_key system call: diff --git a/Documentation/keys.txt b/Documentation/keys.txt index 51652d3..b82d38d 100644 --- a/Documentation/keys.txt +++ b/Documentation/keys.txt @@ -771,7 +771,7 @@ payload contents" for more information. struct key *request_key(const struct key_type *type, const char *description, - const char *callout_string); + const char *callout_info); This is used to request a key or keyring with a description that matches the description specified according to the key type's match function. This @@ -793,24 +793,28 @@ payload contents" for more information. struct key *request_key_with_auxdata(const struct key_type *type, const char *description, - const char *callout_string, + const void *callout_info, + size_t callout_len, void *aux); This is identical to request_key(), except that the auxiliary data is - passed to the key_type->request_key() op if it exists. + passed to the key_type->request_key() op if it exists, and the callout_info + is a blob of length callout_len, if given (the length may be 0). (*) A key can be requested asynchronously by calling one of: struct key *request_key_async(const struct key_type *type, const char *description, - const char *callout_string); + const void *callout_info, + size_t callout_len); or: struct key *request_key_async_with_auxdata(const struct key_type *type, const char *description, - const char *callout_string, + const char *callout_info, + size_t callout_len, void *aux); which are asynchronous equivalents of request_key() and diff --git a/include/linux/key.h b/include/linux/key.h index a70b8a8..163f864 100644 --- a/include/linux/key.h +++ b/include/linux/key.h @@ -208,16 +208,19 @@ extern struct key *request_key(struct key_type *type, extern struct key *request_key_with_auxdata(struct key_type *type, const char *description, - const char *callout_info, + const void *callout_info, + size_t callout_len, void *aux); extern struct key *request_key_async(struct key_type *type, const char *description, - const char *callout_info); + const void *callout_info, + size_t callout_len); extern struct key *request_key_async_with_auxdata(struct key_type *type, const char *description, - const char *callout_info, + const void *callout_info, + size_t callout_len, void *aux); extern int wait_for_key_construction(struct key *key, bool intr); diff --git a/security/keys/internal.h b/security/keys/internal.h index 7d894ef..3cc04c2 100644 --- a/security/keys/internal.h +++ b/security/keys/internal.h @@ -109,7 +109,8 @@ extern int install_process_keyring(struct task_struct *tsk); extern struct key *request_key_and_link(struct key_type *type, const char *description, - const char *callout_info, + const void *callout_info, + size_t callout_len, void *aux, struct key *dest_keyring, unsigned long flags); @@ -120,13 +121,15 @@ extern struct key *request_key_and_link(struct key_type *type, struct request_key_auth { struct key *target_key; struct task_struct *context; - char *callout_info; + void *callout_info; + size_t callout_len; pid_t pid; }; extern struct key_type key_type_request_key_auth; extern struct key *request_key_auth_new(struct key *target, - const char *callout_info); + const void *callout_info, + size_t callout_len); extern struct key *key_get_instantiation_authkey(key_serial_t target_id); diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index 8ec8432..1698bf9 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -152,6 +152,7 @@ asmlinkage long sys_request_key(const char __user *_type, struct key_type *ktype; struct key *key; key_ref_t dest_ref; + size_t callout_len; char type[32], *description, *callout_info; long ret; @@ -169,12 +170,14 @@ asmlinkage long sys_request_key(const char __user *_type, /* pull the callout info into kernel space */ callout_info = NULL; + callout_len = 0; if (_callout_info) { callout_info = strndup_user(_callout_info, PAGE_SIZE); if (IS_ERR(callout_info)) { ret = PTR_ERR(callout_info); goto error2; } + callout_len = strlen(callout_info); } /* get the destination keyring if specified */ @@ -195,8 +198,8 @@ asmlinkage long sys_request_key(const char __user *_type, } /* do the search */ - key = request_key_and_link(ktype, description, callout_info, NULL, - key_ref_to_ptr(dest_ref), + key = request_key_and_link(ktype, description, callout_info, + callout_len, NULL, key_ref_to_ptr(dest_ref), KEY_ALLOC_IN_QUOTA); if (IS_ERR(key)) { ret = PTR_ERR(key); diff --git a/security/keys/request_key.c b/security/keys/request_key.c index 5ecc505..a3f94c6 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -161,21 +161,22 @@ error_alloc: * call out to userspace for key construction * - we ignore program failure and go on key status instead */ -static int construct_key(struct key *key, const char *callout_info, void *aux) +static int construct_key(struct key *key, const void *callout_info, + size_t callout_len, void *aux) { struct key_construction *cons; request_key_actor_t actor; struct key *authkey; int ret; - kenter("%d,%s,%p", key->serial, callout_info, aux); + kenter("%d,%p,%zu,%p", key->serial, callout_info, callout_len, aux); cons = kmalloc(sizeof(*cons), GFP_KERNEL); if (!cons) return -ENOMEM; /* allocate an authorisation key */ - authkey = request_key_auth_new(key, callout_info); + authkey = request_key_auth_new(key, callout_info, callout_len); if (IS_ERR(authkey)) { kfree(cons); ret = PTR_ERR(authkey); @@ -331,6 +332,7 @@ alloc_failed: static struct key *construct_key_and_link(struct key_type *type, const char *description, const char *callout_info, + size_t callout_len, void *aux, struct key *dest_keyring, unsigned long flags) @@ -348,7 +350,7 @@ static struct key *construct_key_and_link(struct key_type *type, key_user_put(user); if (ret == 0) { - ret = construct_key(key, callout_info, aux); + ret = construct_key(key, callout_info, callout_len, aux); if (ret < 0) goto construction_failed; } @@ -370,7 +372,8 @@ construction_failed: */ struct key *request_key_and_link(struct key_type *type, const char *description, - const char *callout_info, + const void *callout_info, + size_t callout_len, void *aux, struct key *dest_keyring, unsigned long flags) @@ -378,8 +381,8 @@ struct key *request_key_and_link(struct key_type *type, struct key *key; key_ref_t key_ref; - kenter("%s,%s,%s,%p,%p,%lx", - type->name, description, callout_info, aux, + kenter("%s,%s,%p,%zu,%p,%p,%lx", + type->name, description, callout_info, callout_len, aux, dest_keyring, flags); /* search all the process keyrings for a key */ @@ -398,7 +401,8 @@ struct key *request_key_and_link(struct key_type *type, goto error; key = construct_key_and_link(type, description, callout_info, - aux, dest_keyring, flags); + callout_len, aux, dest_keyring, + flags); } error: @@ -434,10 +438,13 @@ struct key *request_key(struct key_type *type, const char *callout_info) { struct key *key; + size_t callout_len = 0; int ret; - key = request_key_and_link(type, description, callout_info, NULL, - NULL, KEY_ALLOC_IN_QUOTA); + if (callout_info) + callout_len = strlen(callout_info); + key = request_key_and_link(type, description, callout_info, callout_len, + NULL, NULL, KEY_ALLOC_IN_QUOTA); if (!IS_ERR(key)) { ret = wait_for_key_construction(key, false); if (ret < 0) { @@ -458,14 +465,15 @@ EXPORT_SYMBOL(request_key); */ struct key *request_key_with_auxdata(struct key_type *type, const char *description, - const char *callout_info, + const void *callout_info, + size_t callout_len, void *aux) { struct key *key; int ret; - key = request_key_and_link(type, description, callout_info, aux, - NULL, KEY_ALLOC_IN_QUOTA); + key = request_key_and_link(type, description, callout_info, callout_len, + aux, NULL, KEY_ALLOC_IN_QUOTA); if (!IS_ERR(key)) { ret = wait_for_key_construction(key, false); if (ret < 0) { @@ -485,10 +493,12 @@ EXPORT_SYMBOL(request_key_with_auxdata); */ struct key *request_key_async(struct key_type *type, const char *description, - const char *callout_info) + const void *callout_info, + size_t callout_len) { - return request_key_and_link(type, description, callout_info, NULL, - NULL, KEY_ALLOC_IN_QUOTA); + return request_key_and_link(type, description, callout_info, + callout_len, NULL, NULL, + KEY_ALLOC_IN_QUOTA); } EXPORT_SYMBOL(request_key_async); @@ -500,10 +510,11 @@ EXPORT_SYMBOL(request_key_async); */ struct key *request_key_async_with_auxdata(struct key_type *type, const char *description, - const char *callout_info, + const void *callout_info, + size_t callout_len, void *aux) { - return request_key_and_link(type, description, callout_info, aux, - NULL, KEY_ALLOC_IN_QUOTA); + return request_key_and_link(type, description, callout_info, + callout_len, aux, NULL, KEY_ALLOC_IN_QUOTA); } EXPORT_SYMBOL(request_key_async_with_auxdata); diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c index e42b525..c615d47 100644 --- a/security/keys/request_key_auth.c +++ b/security/keys/request_key_auth.c @@ -61,7 +61,7 @@ static void request_key_auth_describe(const struct key *key, seq_puts(m, "key:"); seq_puts(m, key->description); - seq_printf(m, " pid:%d ci:%zu", rka->pid, strlen(rka->callout_info)); + seq_printf(m, " pid:%d ci:%zu", rka->pid, rka->callout_len); } /* end request_key_auth_describe() */ @@ -77,7 +77,7 @@ static long request_key_auth_read(const struct key *key, size_t datalen; long ret; - datalen = strlen(rka->callout_info); + datalen = rka->callout_len; ret = datalen; /* we can return the data as is */ @@ -137,7 +137,8 @@ static void request_key_auth_destroy(struct key *key) * create an authorisation token for /sbin/request-key or whoever to gain * access to the caller's security data */ -struct key *request_key_auth_new(struct key *target, const char *callout_info) +struct key *request_key_auth_new(struct key *target, const void *callout_info, + size_t callout_len) { struct request_key_auth *rka, *irka; struct key *authkey = NULL; @@ -152,7 +153,7 @@ struct key *request_key_auth_new(struct key *target, const char *callout_info) kleave(" = -ENOMEM"); return ERR_PTR(-ENOMEM); } - rka->callout_info = kmalloc(strlen(callout_info) + 1, GFP_KERNEL); + rka->callout_info = kmalloc(callout_len, GFP_KERNEL); if (!rka->callout_info) { kleave(" = -ENOMEM"); kfree(rka); @@ -186,7 +187,8 @@ struct key *request_key_auth_new(struct key *target, const char *callout_info) } rka->target_key = key_get(target); - strcpy(rka->callout_info, callout_info); + memcpy(rka->callout_info, callout_info, callout_len); + rka->callout_len = callout_len; /* allocate the auth key */ sprintf(desc, "%x", target->serial); -- cgit v1.1