API: add VIR_TYPED_PARAM_STRING

This allows strings to be transported between client and server
in the context of name-type-value virTypedParameter functions.
For compatibility,

    o new clients will not send strings to old servers, based on
      a feature check
    o new servers will not send strings to old clients without the
      flag VIR_TYPED_PARAM_STRING_OKAY; this will be enforced at
      the RPC layer in the next patch, so that drivers need not
      worry about it in general.  The one exception is that
      virDomainGetSchedulerParameters lacks a flags argument, so
      it must not return a string; drivers that forward that
      function on to virDomainGetSchedulerParametersFlags will
      have to pay attention to the flag.
    o the flag VIR_TYPED_PARAM_STRING_OKAY is set automatically,
      based on a feature check (so far, no driver implements it),
      so clients do not have to worry about it

Future patches can then enable the feature on a per-driver basis.

This patch also ensures that drivers can blindly strdup() field
names (previously, a malicious client could stuff 80 non-NUL bytes
into field and cause a read overrun).

* src/libvirt_internal.h (VIR_DRV_FEATURE_TYPED_PARAM_STRING): New
driver feature.
* src/libvirt.c (virTypedParameterValidateSet)
(virTypedParameterSanitizeGet): New helper functions.
(virDomainSetMemoryParameters, virDomainSetBlkioParameters)
(virDomainSetSchedulerParameters)
(virDomainSetSchedulerParametersFlags)
(virDomainGetMemoryParameters, virDomainGetBlkioParameters)
(virDomainGetSchedulerParameters)
(virDomainGetSchedulerParametersFlags, virDomainBlockStatsFlags):
Use them.
* src/util/util.h (virTypedParameterArrayClear): New helper
function.
* src/util/util.c (virTypedParameterArrayClear): Implement it.
* src/libvirt_private.syms (util.h): Export it.
Based on an initial patch by Hu Tao, with feedback from
Daniel P. Berrange.

Signed-off-by: Eric Blake <eblake@redhat.com>
This commit is contained in:
Eric Blake
2011-10-12 17:26:34 +08:00
parent 329b2b2819
commit a218c81da2
6 changed files with 136 additions and 18 deletions

View File

@@ -200,11 +200,14 @@ typedef virDomainControlInfo *virDomainControlInfoPtr;
* current domain state. VIR_DOMAIN_AFFECT_LIVE requires a running
* domain, and VIR_DOMAIN_AFFECT_CONFIG requires a persistent domain
* (whether or not it is running).
*
* These enums should not conflict with those of virTypedParameterFlags.
*/
typedef enum {
VIR_DOMAIN_AFFECT_CURRENT = 0, /* Affect current domain state. */
VIR_DOMAIN_AFFECT_LIVE = 1 << 0, /* Affect running domain state. */
VIR_DOMAIN_AFFECT_CONFIG = 1 << 1, /* Affect persistent domain state. */
/* 1 << 2 is reserved for virTypedParameterFlags */
} virDomainModificationImpact;
/**
@@ -489,9 +492,35 @@ typedef enum {
VIR_TYPED_PARAM_LLONG = 3, /* long long case */
VIR_TYPED_PARAM_ULLONG = 4, /* unsigned long long case */
VIR_TYPED_PARAM_DOUBLE = 5, /* double case */
VIR_TYPED_PARAM_BOOLEAN = 6 /* boolean(character) case */
VIR_TYPED_PARAM_BOOLEAN = 6, /* boolean(character) case */
VIR_TYPED_PARAM_STRING = 7, /* string case */
} virTypedParameterType;
/**
* virTypedParameterFlags:
*
* Flags related to libvirt APIs that use virTypedParameter.
*
* These enums should not conflict with those of virDomainModificationImpact.
*/
typedef enum {
/* 1 << 0 is reserved for virDomainModificationImpact */
/* 1 << 1 is reserved for virDomainModificationImpact */
/* Older servers lacked the ability to handle string typed
* parameters. Attempts to set a string parameter with an older
* server will fail at the client, but attempts to retrieve
* parameters must not return strings from a new server to an
* older client, so this flag exists to identify newer clients to
* newer servers. This flag is automatically set when needed, so
* the user does not have to worry about it; however, manually
* setting the flag can be used to reject servers that cannot
* return typed strings, even if no strings would be returned.
*/
VIR_TYPED_PARAM_STRING_OKAY = 1 << 2,
} virTypedParameterFlags;
/**
* VIR_TYPED_PARAM_FIELD_LENGTH:
*
@@ -520,6 +549,7 @@ struct _virTypedParameter {
unsigned long long int ul; /* type is ULLONG */
double d; /* type is DOUBLE */
char b; /* type is BOOLEAN */
char *s; /* type is STRING, may not be NULL */
} value; /* parameter value */
};