From 9c937dcc71021f2dbf78f904f03d962dd9bcc130 Mon Sep 17 00:00:00 2001 From: Amy Griffis Date: Thu, 8 Jun 2006 23:19:31 -0400 Subject: [PATCH] log more info for directory entry change events When an audit event involves changes to a directory entry, include a PATH record for the directory itself. A few other notable changes: - fixed audit_inode_child() hooks in fsnotify_move() - removed unused flags arg from audit_inode() - added audit log routines for logging a portion of a string Here's some sample output. before patch: type=SYSCALL msg=audit(1149821605.320:26): arch=40000003 syscall=39 success=yes exit=0 a0=bf8d3c7c a1=1ff a2=804e1b8 a3=bf8d3c7c items=1 ppid=739 pid=800 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=ttyS0 comm="mkdir" exe="/bin/mkdir" subj=root:system_r:unconfined_t:s0-s0:c0.c255 type=CWD msg=audit(1149821605.320:26): cwd="/root" type=PATH msg=audit(1149821605.320:26): item=0 name="foo" parent=164068 inode=164010 dev=03:00 mode=040755 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_t:s0 after patch: type=SYSCALL msg=audit(1149822032.332:24): arch=40000003 syscall=39 success=yes exit=0 a0=bfdd9c7c a1=1ff a2=804e1b8 a3=bfdd9c7c items=2 ppid=714 pid=777 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=ttyS0 comm="mkdir" exe="/bin/mkdir" subj=root:system_r:unconfined_t:s0-s0:c0.c255 type=CWD msg=audit(1149822032.332:24): cwd="/root" type=PATH msg=audit(1149822032.332:24): item=0 name="/root" inode=164068 dev=03:00 mode=040750 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_dir_t:s0 type=PATH msg=audit(1149822032.332:24): item=1 name="foo" inode=164010 dev=03:00 mode=040755 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_t:s0 Signed-off-by: Amy Griffis Signed-off-by: Al Viro --- kernel/audit.c | 54 ++++++++++++++++++++-- kernel/audit.h | 3 +- kernel/auditfilter.c | 8 +++- kernel/auditsc.c | 123 +++++++++++++++++++++++++++++---------------------- 4 files changed, 127 insertions(+), 61 deletions(-) (limited to 'kernel') diff --git a/kernel/audit.c b/kernel/audit.c index 0fbf1c116363..7dfac7031bd7 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -1051,20 +1051,53 @@ void audit_log_hex(struct audit_buffer *ab, const unsigned char *buf, skb_put(skb, len << 1); /* new string is twice the old string */ } +/* + * Format a string of no more than slen characters into the audit buffer, + * enclosed in quote marks. + */ +static void audit_log_n_string(struct audit_buffer *ab, size_t slen, + const char *string) +{ + int avail, new_len; + unsigned char *ptr; + struct sk_buff *skb; + + BUG_ON(!ab->skb); + skb = ab->skb; + avail = skb_tailroom(skb); + new_len = slen + 3; /* enclosing quotes + null terminator */ + if (new_len > avail) { + avail = audit_expand(ab, new_len); + if (!avail) + return; + } + ptr = skb->tail; + *ptr++ = '"'; + memcpy(ptr, string, slen); + ptr += slen; + *ptr++ = '"'; + *ptr = 0; + skb_put(skb, slen + 2); /* don't include null terminator */ +} + /** - * audit_log_unstrustedstring - log a string that may contain random characters + * audit_log_n_unstrustedstring - log a string that may contain random characters * @ab: audit_buffer + * @len: lenth of string (not including trailing null) * @string: string to be logged * * This code will escape a string that is passed to it if the string * contains a control character, unprintable character, double quote mark, * or a space. Unescaped strings will start and end with a double quote mark. * Strings that are escaped are printed in hex (2 digits per char). + * + * The caller specifies the number of characters in the string to log, which may + * or may not be the entire string. */ -const char *audit_log_untrustedstring(struct audit_buffer *ab, const char *string) +const char *audit_log_n_untrustedstring(struct audit_buffer *ab, size_t len, + const char *string) { const unsigned char *p = string; - size_t len = strlen(string); while (*p) { if (*p == '"' || *p < 0x21 || *p > 0x7f) { @@ -1073,10 +1106,23 @@ const char *audit_log_untrustedstring(struct audit_buffer *ab, const char *strin } p++; } - audit_log_format(ab, "\"%s\"", string); + audit_log_n_string(ab, len, string); return p + 1; } +/** + * audit_log_unstrustedstring - log a string that may contain random characters + * @ab: audit_buffer + * @string: string to be logged + * + * Same as audit_log_n_unstrustedstring(), except that strlen is used to + * determine string length. + */ +const char *audit_log_untrustedstring(struct audit_buffer *ab, const char *string) +{ + return audit_log_n_untrustedstring(ab, strlen(string), string); +} + /* This is a helper-function to print the escaped d_path */ void audit_log_d_path(struct audit_buffer *ab, const char *prefix, struct dentry *dentry, struct vfsmount *vfsmnt) diff --git a/kernel/audit.h b/kernel/audit.h index 58fa44cb8d01..8323e4132a33 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -104,7 +104,8 @@ static inline int audit_hash_ino(u32 ino) } extern int audit_comparator(const u32 left, const u32 op, const u32 right); -extern int audit_compare_dname_path(const char *dname, const char *path); +extern int audit_compare_dname_path(const char *dname, const char *path, + int *dirlen); extern struct sk_buff * audit_make_reply(int pid, int seq, int type, int done, int multi, void *payload, int size); diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index a536f7148bcd..4c99d2c586ed 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -787,7 +787,7 @@ static void audit_update_watch(struct audit_parent *parent, mutex_lock(&audit_filter_mutex); list_for_each_entry_safe(owatch, nextw, &parent->watches, wlist) { - if (audit_compare_dname_path(dname, owatch->path)) + if (audit_compare_dname_path(dname, owatch->path, NULL)) continue; /* If the update involves invalidating rules, do the inode-based @@ -1387,7 +1387,8 @@ int audit_comparator(const u32 left, const u32 op, const u32 right) /* Compare given dentry name with last component in given path, * return of 0 indicates a match. */ -int audit_compare_dname_path(const char *dname, const char *path) +int audit_compare_dname_path(const char *dname, const char *path, + int *dirlen) { int dlen, plen; const char *p; @@ -1416,6 +1417,9 @@ int audit_compare_dname_path(const char *dname, const char *path) p++; } + /* return length of path's directory component */ + if (dirlen) + *dirlen = p - path; return strncmp(p, dname, dlen); } diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 174a3f624892..851ae0217e4b 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -82,6 +82,9 @@ extern int audit_enabled; * path_lookup. */ #define AUDIT_NAMES_RESERVED 7 +/* Indicates that audit should log the full pathname. */ +#define AUDIT_NAME_FULL -1 + /* When fs/namei.c:getname() is called, we store the pointer in name and * we don't let putname() free it (instead we free all of the saved * pointers at syscall exit time). @@ -89,8 +92,9 @@ extern int audit_enabled; * Further, in fs/namei.c:path_lookup() we store the inode and device. */ struct audit_names { const char *name; + int name_len; /* number of name's characters to log */ + unsigned name_put; /* call __putname() for this name */ unsigned long ino; - unsigned long pino; dev_t dev; umode_t mode; uid_t uid; @@ -296,12 +300,10 @@ static int audit_filter_rules(struct task_struct *tsk, break; case AUDIT_INODE: if (name) - result = (name->ino == f->val || - name->pino == f->val); + result = (name->ino == f->val); else if (ctx) { for (j = 0; j < ctx->name_count; j++) { - if (audit_comparator(ctx->names[j].ino, f->op, f->val) || - audit_comparator(ctx->names[j].pino, f->op, f->val)) { + if (audit_comparator(ctx->names[j].ino, f->op, f->val)) { ++result; break; } @@ -311,8 +313,7 @@ static int audit_filter_rules(struct task_struct *tsk, case AUDIT_WATCH: if (name && rule->watch->ino != (unsigned long)-1) result = (name->dev == rule->watch->dev && - (name->ino == rule->watch->ino || - name->pino == rule->watch->ino)); + name->ino == rule->watch->ino); break; case AUDIT_LOGINUID: result = 0; @@ -526,7 +527,7 @@ static inline void audit_free_names(struct audit_context *context) #endif for (i = 0; i < context->name_count; i++) { - if (context->names[i].name) + if (context->names[i].name && context->names[i].name_put) __putname(context->names[i].name); } context->name_count = 0; @@ -850,8 +851,7 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts } } for (i = 0; i < context->name_count; i++) { - unsigned long ino = context->names[i].ino; - unsigned long pino = context->names[i].pino; + struct audit_names *n = &context->names[i]; ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH); if (!ab) @@ -859,33 +859,47 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts audit_log_format(ab, "item=%d", i); - audit_log_format(ab, " name="); - if (context->names[i].name) - audit_log_untrustedstring(ab, context->names[i].name); - else - audit_log_format(ab, "(null)"); - - if (pino != (unsigned long)-1) - audit_log_format(ab, " parent=%lu", pino); - if (ino != (unsigned long)-1) - audit_log_format(ab, " inode=%lu", ino); - if ((pino != (unsigned long)-1) || (ino != (unsigned long)-1)) - audit_log_format(ab, " dev=%02x:%02x mode=%#o" - " ouid=%u ogid=%u rdev=%02x:%02x", - MAJOR(context->names[i].dev), - MINOR(context->names[i].dev), - context->names[i].mode, - context->names[i].uid, - context->names[i].gid, - MAJOR(context->names[i].rdev), - MINOR(context->names[i].rdev)); - if (context->names[i].osid != 0) { + if (n->name) { + switch(n->name_len) { + case AUDIT_NAME_FULL: + /* log the full path */ + audit_log_format(ab, " name="); + audit_log_untrustedstring(ab, n->name); + break; + case 0: + /* name was specified as a relative path and the + * directory component is the cwd */ + audit_log_d_path(ab, " name=", context->pwd, + context->pwdmnt); + break; + default: + /* log the name's directory component */ + audit_log_format(ab, " name="); + audit_log_n_untrustedstring(ab, n->name_len, + n->name); + } + } else + audit_log_format(ab, " name=(null)"); + + if (n->ino != (unsigned long)-1) { + audit_log_format(ab, " inode=%lu" + " dev=%02x:%02x mode=%#o" + " ouid=%u ogid=%u rdev=%02x:%02x", + n->ino, + MAJOR(n->dev), + MINOR(n->dev), + n->mode, + n->uid, + n->gid, + MAJOR(n->rdev), + MINOR(n->rdev)); + } + if (n->osid != 0) { char *ctx = NULL; u32 len; if (selinux_ctxid_to_string( - context->names[i].osid, &ctx, &len)) { - audit_log_format(ab, " osid=%u", - context->names[i].osid); + n->osid, &ctx, &len)) { + audit_log_format(ab, " osid=%u", n->osid); call_panic = 2; } else audit_log_format(ab, " obj=%s", ctx); @@ -1075,6 +1089,8 @@ void __audit_getname(const char *name) } BUG_ON(context->name_count >= AUDIT_NAMES); context->names[context->name_count].name = name; + context->names[context->name_count].name_len = AUDIT_NAME_FULL; + context->names[context->name_count].name_put = 1; context->names[context->name_count].ino = (unsigned long)-1; ++context->name_count; if (!context->pwd) { @@ -1141,11 +1157,10 @@ static void audit_inode_context(int idx, const struct inode *inode) * audit_inode - store the inode and device from a lookup * @name: name being audited * @inode: inode being audited - * @flags: lookup flags (as used in path_lookup()) * * Called from fs/namei.c:path_lookup(). */ -void __audit_inode(const char *name, const struct inode *inode, unsigned flags) +void __audit_inode(const char *name, const struct inode *inode) { int idx; struct audit_context *context = current->audit_context; @@ -1171,20 +1186,13 @@ void __audit_inode(const char *name, const struct inode *inode, unsigned flags) ++context->ino_count; #endif } + context->names[idx].ino = inode->i_ino; context->names[idx].dev = inode->i_sb->s_dev; context->names[idx].mode = inode->i_mode; context->names[idx].uid = inode->i_uid; context->names[idx].gid = inode->i_gid; context->names[idx].rdev = inode->i_rdev; audit_inode_context(idx, inode); - if ((flags & LOOKUP_PARENT) && (strcmp(name, "/") != 0) && - (strcmp(name, ".") != 0)) { - context->names[idx].ino = (unsigned long)-1; - context->names[idx].pino = inode->i_ino; - } else { - context->names[idx].ino = inode->i_ino; - context->names[idx].pino = (unsigned long)-1; - } } /** @@ -1206,34 +1214,40 @@ void __audit_inode_child(const char *dname, const struct inode *inode, { int idx; struct audit_context *context = current->audit_context; + const char *found_name = NULL; + int dirlen = 0; if (!context->in_syscall) return; /* determine matching parent */ if (!dname) - goto no_match; + goto update_context; for (idx = 0; idx < context->name_count; idx++) - if (context->names[idx].pino == pino) { + if (context->names[idx].ino == pino) { const char *name = context->names[idx].name; if (!name) continue; - if (audit_compare_dname_path(dname, name) == 0) - goto update_context; + if (audit_compare_dname_path(dname, name, &dirlen) == 0) { + context->names[idx].name_len = dirlen; + found_name = name; + break; + } } -no_match: - /* catch-all in case match not found */ +update_context: idx = context->name_count++; - context->names[idx].name = NULL; - context->names[idx].pino = pino; #if AUDIT_DEBUG context->ino_count++; #endif + /* Re-use the name belonging to the slot for a matching parent directory. + * All names for this context are relinquished in audit_free_names() */ + context->names[idx].name = found_name; + context->names[idx].name_len = AUDIT_NAME_FULL; + context->names[idx].name_put = 0; /* don't call __putname() */ -update_context: if (inode) { context->names[idx].ino = inode->i_ino; context->names[idx].dev = inode->i_sb->s_dev; @@ -1242,7 +1256,8 @@ update_context: context->names[idx].gid = inode->i_gid; context->names[idx].rdev = inode->i_rdev; audit_inode_context(idx, inode); - } + } else + context->names[idx].ino = (unsigned long)-1; } /** -- cgit v1.2.3