diff options
Diffstat (limited to 'kernel/power/swsusp.c')
-rw-r--r-- | kernel/power/swsusp.c | 202 |
1 files changed, 173 insertions, 29 deletions
diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c index f2bc71b9fe8..d967e875ee8 100644 --- a/kernel/power/swsusp.c +++ b/kernel/power/swsusp.c @@ -31,6 +31,9 @@ * Alex Badea <vampire@go.ro>: * Fixed runaway init * + * Andreas Steinmetz <ast@domdv.de>: + * Added encrypted suspend option + * * More state savers are welcome. Especially for the scsi layer... * * For TODOs,FIXMEs also look in Documentation/power/swsusp.txt @@ -71,8 +74,16 @@ #include <asm/tlbflush.h> #include <asm/io.h> +#include <linux/random.h> +#include <linux/crypto.h> +#include <asm/scatterlist.h> + #include "power.h" +#define CIPHER "aes" +#define MAXKEY 32 +#define MAXIV 32 + /* References to section boundaries */ extern const void __nosave_begin, __nosave_end; @@ -103,7 +114,8 @@ static suspend_pagedir_t *pagedir_save; #define SWSUSP_SIG "S1SUSPEND" static struct swsusp_header { - char reserved[PAGE_SIZE - 20 - sizeof(swp_entry_t)]; + char reserved[PAGE_SIZE - 20 - MAXKEY - MAXIV - sizeof(swp_entry_t)]; + u8 key_iv[MAXKEY+MAXIV]; swp_entry_t swsusp_info; char orig_sig[10]; char sig[10]; @@ -129,6 +141,131 @@ static struct swsusp_info swsusp_info; static unsigned short swapfile_used[MAX_SWAPFILES]; static unsigned short root_swap; +static int write_page(unsigned long addr, swp_entry_t * loc); +static int bio_read_page(pgoff_t page_off, void * page); + +static u8 key_iv[MAXKEY+MAXIV]; + +#ifdef CONFIG_SWSUSP_ENCRYPT + +static int crypto_init(int mode, void **mem) +{ + int error = 0; + int len; + char *modemsg; + struct crypto_tfm *tfm; + + modemsg = mode ? "suspend not possible" : "resume not possible"; + + tfm = crypto_alloc_tfm(CIPHER, CRYPTO_TFM_MODE_CBC); + if(!tfm) { + printk(KERN_ERR "swsusp: no tfm, %s\n", modemsg); + error = -EINVAL; + goto out; + } + + if(MAXKEY < crypto_tfm_alg_min_keysize(tfm)) { + printk(KERN_ERR "swsusp: key buffer too small, %s\n", modemsg); + error = -ENOKEY; + goto fail; + } + + if (mode) + get_random_bytes(key_iv, MAXKEY+MAXIV); + + len = crypto_tfm_alg_max_keysize(tfm); + if (len > MAXKEY) + len = MAXKEY; + + if (crypto_cipher_setkey(tfm, key_iv, len)) { + printk(KERN_ERR "swsusp: key setup failure, %s\n", modemsg); + error = -EKEYREJECTED; + goto fail; + } + + len = crypto_tfm_alg_ivsize(tfm); + + if (MAXIV < len) { + printk(KERN_ERR "swsusp: iv buffer too small, %s\n", modemsg); + error = -EOVERFLOW; + goto fail; + } + + crypto_cipher_set_iv(tfm, key_iv+MAXKEY, len); + + *mem=(void *)tfm; + + goto out; + +fail: crypto_free_tfm(tfm); +out: return error; +} + +static __inline__ void crypto_exit(void *mem) +{ + crypto_free_tfm((struct crypto_tfm *)mem); +} + +static __inline__ int crypto_write(struct pbe *p, void *mem) +{ + int error = 0; + struct scatterlist src, dst; + + src.page = virt_to_page(p->address); + src.offset = 0; + src.length = PAGE_SIZE; + dst.page = virt_to_page((void *)&swsusp_header); + dst.offset = 0; + dst.length = PAGE_SIZE; + + error = crypto_cipher_encrypt((struct crypto_tfm *)mem, &dst, &src, + PAGE_SIZE); + + if (!error) + error = write_page((unsigned long)&swsusp_header, + &(p->swap_address)); + return error; +} + +static __inline__ int crypto_read(struct pbe *p, void *mem) +{ + int error = 0; + struct scatterlist src, dst; + + error = bio_read_page(swp_offset(p->swap_address), (void *)p->address); + if (!error) { + src.offset = 0; + src.length = PAGE_SIZE; + dst.offset = 0; + dst.length = PAGE_SIZE; + src.page = dst.page = virt_to_page((void *)p->address); + + error = crypto_cipher_decrypt((struct crypto_tfm *)mem, &dst, + &src, PAGE_SIZE); + } + return error; +} +#else +static __inline__ int crypto_init(int mode, void *mem) +{ + return 0; +} + +static __inline__ void crypto_exit(void *mem) +{ +} + +static __inline__ int crypto_write(struct pbe *p, void *mem) +{ + return write_page(p->address, &(p->swap_address)); +} + +static __inline__ int crypto_read(struct pbe *p, void *mem) +{ + return bio_read_page(swp_offset(p->swap_address), (void *)p->address); +} +#endif + static int mark_swapfiles(swp_entry_t prev) { int error; @@ -140,6 +277,7 @@ static int mark_swapfiles(swp_entry_t prev) !memcmp("SWAPSPACE2",swsusp_header.sig, 10)) { memcpy(swsusp_header.orig_sig,swsusp_header.sig, 10); memcpy(swsusp_header.sig,SWSUSP_SIG, 10); + memcpy(swsusp_header.key_iv, key_iv, MAXKEY+MAXIV); swsusp_header.swsusp_info = prev; error = rw_swap_page_sync(WRITE, swp_entry(root_swap, 0), @@ -179,9 +317,9 @@ static int swsusp_swap_check(void) /* This is called before saving image */ len=strlen(resume_file); root_swap = 0xFFFF; - swap_list_lock(); + spin_lock(&swap_lock); for (i=0; i<MAX_SWAPFILES; i++) { - if (swap_info[i].flags == 0) { + if (!(swap_info[i].flags & SWP_WRITEOK)) { swapfile_used[i]=SWAPFILE_UNUSED; } else { if (!len) { @@ -202,7 +340,7 @@ static int swsusp_swap_check(void) /* This is called before saving image */ } } } - swap_list_unlock(); + spin_unlock(&swap_lock); return (root_swap != 0xffff) ? 0 : -ENODEV; } @@ -216,12 +354,12 @@ static void lock_swapdevices(void) { int i; - swap_list_lock(); + spin_lock(&swap_lock); for (i = 0; i< MAX_SWAPFILES; i++) if (swapfile_used[i] == SWAPFILE_IGNORED) { - swap_info[i].flags ^= 0xFF; + swap_info[i].flags ^= SWP_WRITEOK; } - swap_list_unlock(); + spin_unlock(&swap_lock); } /** @@ -286,6 +424,10 @@ static int data_write(void) int error = 0, i = 0; unsigned int mod = nr_copy_pages / 100; struct pbe *p; + void *tfm; + + if ((error = crypto_init(1, &tfm))) + return error; if (!mod) mod = 1; @@ -294,11 +436,14 @@ static int data_write(void) for_each_pbe (p, pagedir_nosave) { if (!(i%mod)) printk( "\b\b\b\b%3d%%", i / mod ); - if ((error = write_page(p->address, &(p->swap_address)))) + if ((error = crypto_write(p, tfm))) { + crypto_exit(tfm); return error; + } i++; } printk("\b\b\b\bdone\n"); + crypto_exit(tfm); return error; } @@ -385,7 +530,6 @@ static int write_pagedir(void) * write_suspend_image - Write entire image and metadata. * */ - static int write_suspend_image(void) { int error; @@ -400,6 +544,7 @@ static int write_suspend_image(void) if ((error = close_swap())) goto FreePagedir; Done: + memset(key_iv, 0, MAXKEY+MAXIV); return error; FreePagedir: free_pagedir_entries(); @@ -591,18 +736,7 @@ static void copy_data_pages(void) static int calc_nr(int nr_copy) { - int extra = 0; - int mod = !!(nr_copy % PBES_PER_PAGE); - int diff = (nr_copy / PBES_PER_PAGE) + mod; - - do { - extra += diff; - nr_copy += diff; - mod = !!(nr_copy % PBES_PER_PAGE); - diff = (nr_copy / PBES_PER_PAGE) + mod - extra; - } while (diff > 0); - - return nr_copy; + return nr_copy + (nr_copy+PBES_PER_PAGE-2)/(PBES_PER_PAGE-1); } /** @@ -886,20 +1020,21 @@ int swsusp_suspend(void) * at resume time, and evil weirdness ensues. */ if ((error = device_power_down(PMSG_FREEZE))) { + printk(KERN_ERR "Some devices failed to power down, aborting suspend\n"); local_irq_enable(); return error; } if ((error = swsusp_swap_check())) { - printk(KERN_ERR "swsusp: FATAL: cannot find swap device, try " - "swapon -a!\n"); + printk(KERN_ERR "swsusp: cannot find swap device, try swapon -a.\n"); + device_power_up(); local_irq_enable(); return error; } save_processor_state(); if ((error = swsusp_arch_suspend())) - printk("Error %d suspending\n", error); + printk(KERN_ERR "Error %d suspending\n", error); /* Restore control flow magically appears here */ restore_processor_state(); BUG_ON (nr_copy_pages_check != nr_copy_pages); @@ -924,6 +1059,7 @@ int swsusp_resume(void) BUG_ON(!error); restore_processor_state(); restore_highmem(); + touch_softlockup_watchdog(); device_power_up(); local_irq_enable(); return error; @@ -1179,7 +1315,8 @@ static const char * sanity_check(void) if (strcmp(swsusp_info.uts.machine,system_utsname.machine)) return "machine"; #if 0 - if(swsusp_info.cpus != num_online_cpus()) + /* We can't use number of online CPUs when we use hotplug to remove them ;-))) */ + if (swsusp_info.cpus != num_possible_cpus()) return "number of cpus"; #endif return NULL; @@ -1212,13 +1349,14 @@ static int check_sig(void) return error; if (!memcmp(SWSUSP_SIG, swsusp_header.sig, 10)) { memcpy(swsusp_header.sig, swsusp_header.orig_sig, 10); + memcpy(key_iv, swsusp_header.key_iv, MAXKEY+MAXIV); + memset(swsusp_header.key_iv, 0, MAXKEY+MAXIV); /* * Reset swap signature now. */ error = bio_write_page(0, &swsusp_header); } else { - printk(KERN_ERR "swsusp: Suspend partition has wrong signature?\n"); return -EINVAL; } if (!error) @@ -1239,6 +1377,10 @@ static int data_read(struct pbe *pblist) int error = 0; int i = 0; int mod = swsusp_info.image_pages / 100; + void *tfm; + + if ((error = crypto_init(0, &tfm))) + return error; if (!mod) mod = 1; @@ -1250,14 +1392,15 @@ static int data_read(struct pbe *pblist) if (!(i % mod)) printk("\b\b\b\b%3d%%", i / mod); - error = bio_read_page(swp_offset(p->swap_address), - (void *)p->address); - if (error) + if ((error = crypto_read(p, tfm))) { + crypto_exit(tfm); return error; + } i++; } printk("\b\b\b\bdone\n"); + crypto_exit(tfm); return error; } @@ -1385,6 +1528,7 @@ int swsusp_read(void) error = read_suspend_image(); blkdev_put(resume_bdev); + memset(key_iv, 0, MAXKEY+MAXIV); if (!error) pr_debug("swsusp: Reading resume file was successful\n"); |