| OLD | NEW |
| 1 /* | 1 /* |
| 2 * rdbx.h | 2 * rdbx.h |
| 3 * | 3 * |
| 4 * replay database with extended packet indices, using a rollover counter | 4 * replay database with extended packet indices, using a rollover counter |
| 5 * | 5 * |
| 6 * David A. McGrew | 6 * David A. McGrew |
| 7 * Cisco Systems, Inc. | 7 * Cisco Systems, Inc. |
| 8 * | 8 * |
| 9 */ | 9 */ |
| 10 | 10 |
| (...skipping 32 matching lines...) Expand 10 before | Expand all | Expand 10 after Loading... |
| 43 * OF THE POSSIBILITY OF SUCH DAMAGE. | 43 * OF THE POSSIBILITY OF SUCH DAMAGE. |
| 44 * | 44 * |
| 45 */ | 45 */ |
| 46 | 46 |
| 47 #ifndef RDBX_H | 47 #ifndef RDBX_H |
| 48 #define RDBX_H | 48 #define RDBX_H |
| 49 | 49 |
| 50 #include "datatypes.h" | 50 #include "datatypes.h" |
| 51 #include "err.h" | 51 #include "err.h" |
| 52 | 52 |
| 53 /** | 53 #ifdef __cplusplus |
| 54 * Compatibility shim for v1->v2 transition. | 54 extern "C" { |
| 55 */ | 55 #endif |
| 56 | 56 |
| 57 #define srtp_rdbx_get_packet_index rdbx_get_packet_index | 57 /* #define ROC_TEST */ |
| 58 | |
| 59 /* #define ROC_TEST */ | |
| 60 | 58 |
| 61 #ifndef ROC_TEST | 59 #ifndef ROC_TEST |
| 62 | 60 |
| 63 typedef uint16_t sequence_number_t; /* 16 bit sequence number */ | 61 typedef uint16_t srtp_sequence_number_t; /* 16 bit sequence number */ |
| 64 typedef uint32_t rollover_counter_t; /* 32 bit rollover counter */ | 62 typedef uint32_t srtp_rollover_counter_t; /* 32 bit rollover counter */ |
| 65 | 63 |
| 66 #else /* use small seq_num and roc datatypes for testing purposes */ | 64 #else /* use small seq_num and roc datatypes for testing purposes */ |
| 67 | 65 |
| 68 typedef unsigned char sequence_number_t; /* 8 bit sequence number */ | 66 typedef unsigned char srtp_sequence_number_t; /* 8 bit sequence number */ |
| 69 typedef uint16_t rollover_counter_t; /* 16 bit rollover counter */ | 67 typedef uint16_t srtp_rollover_counter_t; /* 16 bit rollover counter */ |
| 70 | 68 |
| 71 #endif | 69 #endif |
| 72 | 70 |
| 73 #define seq_num_median (1 << (8*sizeof(sequence_number_t) - 1)) | 71 #define seq_num_median (1 << (8 * sizeof(srtp_sequence_number_t) - 1)) |
| 74 #define seq_num_max (1 << (8*sizeof(sequence_number_t))) | 72 #define seq_num_max (1 << (8 * sizeof(srtp_sequence_number_t))) |
| 75 | 73 |
| 76 /* | 74 /* |
| 77 * An xtd_seq_num_t is a 64-bit unsigned integer used as an 'extended' | 75 * An rtp_xtd_seq_num_t is a 64-bit unsigned integer used as an 'extended' |
| 78 * sequence number. | 76 * sequence number. |
| 79 */ | 77 */ |
| 80 | 78 typedef uint64_t srtp_xtd_seq_num_t; |
| 81 typedef uint64_t xtd_seq_num_t; | |
| 82 | 79 |
| 83 | 80 |
| 84 /* | 81 /* |
| 85 * An rdbx_t is a replay database with extended range; it uses an | 82 * An srtp_rdbx_t is a replay database with extended range; it uses an |
| 86 * xtd_seq_num_t and a bitmask of recently received indices. | 83 * xtd_seq_num_t and a bitmask of recently received indices. |
| 87 */ | 84 */ |
| 88 | |
| 89 typedef struct { | 85 typedef struct { |
| 90 xtd_seq_num_t index; | 86 srtp_xtd_seq_num_t index; |
| 91 bitvector_t bitmask; | 87 bitvector_t bitmask; |
| 92 } rdbx_t; | 88 } srtp_rdbx_t; |
| 93 | 89 |
| 94 | 90 |
| 95 /* | 91 /* |
| 96 * rdbx_init(rdbx_ptr, ws) | 92 * srtp_rdbx_init(rdbx_ptr, ws) |
| 97 * | 93 * |
| 98 * initializes the rdbx pointed to by its argument with the window size ws, | 94 * initializes the rdbx pointed to by its argument with the window size ws, |
| 99 * setting the rollover counter and sequence number to zero | 95 * setting the rollover counter and sequence number to zero |
| 100 */ | 96 */ |
| 101 | 97 srtp_err_status_t srtp_rdbx_init(srtp_rdbx_t *rdbx, unsigned long ws); |
| 102 err_status_t | |
| 103 rdbx_init(rdbx_t *rdbx, unsigned long ws); | |
| 104 | 98 |
| 105 | 99 |
| 106 /* | 100 /* |
| 107 * rdbx_dealloc(rdbx_ptr) | 101 * srtp_rdbx_dealloc(rdbx_ptr) |
| 108 * | 102 * |
| 109 * frees memory associated with the rdbx | 103 * frees memory associated with the rdbx |
| 110 */ | 104 */ |
| 111 | 105 srtp_err_status_t srtp_rdbx_dealloc(srtp_rdbx_t *rdbx); |
| 112 err_status_t | |
| 113 rdbx_dealloc(rdbx_t *rdbx); | |
| 114 | 106 |
| 115 | 107 |
| 116 /* | 108 /* |
| 117 * rdbx_estimate_index(rdbx, guess, s) | 109 * srtp_rdbx_estimate_index(rdbx, guess, s) |
| 118 * | 110 * |
| 119 * given an rdbx and a sequence number s (from a newly arrived packet), | 111 * given an rdbx and a sequence number s (from a newly arrived packet), |
| 120 * sets the contents of *guess to contain the best guess of the packet | 112 * sets the contents of *guess to contain the best guess of the packet |
| 121 * index to which s corresponds, and returns the difference between | 113 * index to which s corresponds, and returns the difference between |
| 122 * *guess and the locally stored synch info | 114 * *guess and the locally stored synch info |
| 123 */ | 115 */ |
| 124 | 116 int srtp_rdbx_estimate_index(const srtp_rdbx_t *rdbx, srtp_xtd_seq_num_t *guess,
srtp_sequence_number_t s); |
| 125 int | |
| 126 rdbx_estimate_index(const rdbx_t *rdbx, | |
| 127 » » xtd_seq_num_t *guess, | |
| 128 » » sequence_number_t s); | |
| 129 | 117 |
| 130 /* | 118 /* |
| 131 * rdbx_check(rdbx, delta); | 119 * srtp_rdbx_check(rdbx, delta); |
| 132 * | 120 * |
| 133 * rdbx_check(&r, delta) checks to see if the xtd_seq_num_t | 121 * srtp_rdbx_check(&r, delta) checks to see if the xtd_seq_num_t |
| 134 * which is at rdbx->window_start + delta is in the rdb | 122 * which is at rdbx->window_start + delta is in the rdb |
| 135 * | 123 * |
| 136 */ | 124 */ |
| 137 | 125 srtp_err_status_t srtp_rdbx_check(const srtp_rdbx_t *rdbx, int difference); |
| 138 err_status_t | |
| 139 rdbx_check(const rdbx_t *rdbx, int difference); | |
| 140 | 126 |
| 141 /* | 127 /* |
| 142 * replay_add_index(rdbx, delta) | 128 * srtp_replay_add_index(rdbx, delta) |
| 143 * | 129 * |
| 144 * adds the xtd_seq_num_t at rdbx->window_start + delta to replay_db | 130 * adds the srtp_xtd_seq_num_t at rdbx->window_start + delta to replay_db |
| 145 * (and does *not* check if that xtd_seq_num_t appears in db) | 131 * (and does *not* check if that xtd_seq_num_t appears in db) |
| 146 * | 132 * |
| 147 * this function should be called *only* after replay_check has | 133 * this function should be called *only* after replay_check has |
| 148 * indicated that the index does not appear in the rdbx, and a mutex | 134 * indicated that the index does not appear in the rdbx, and a mutex |
| 149 * should protect the rdbx between these calls if necessary. | 135 * should protect the rdbx between these calls if necessary. |
| 150 */ | 136 */ |
| 151 | 137 srtp_err_status_t srtp_rdbx_add_index(srtp_rdbx_t *rdbx, int delta); |
| 152 err_status_t | |
| 153 rdbx_add_index(rdbx_t *rdbx, int delta); | |
| 154 | 138 |
| 155 | 139 |
| 156 /* | 140 /* |
| 157 * rdbx_set_roc(rdbx, roc) initalizes the rdbx_t at the location rdbx | 141 * srtp_rdbx_set_roc(rdbx, roc) initalizes the srtp_rdbx_t at the location rdbx |
| 158 * to have the rollover counter value roc. If that value is less than | 142 * to have the rollover counter value roc. If that value is less than |
| 159 * the current rollover counter value, then the function returns | 143 * the current rollover counter value, then the function returns |
| 160 * err_status_replay_old; otherwise, err_status_ok is returned. | 144 * srtp_err_status_replay_old; otherwise, srtp_err_status_ok is returned. |
| 161 * | 145 * |
| 162 */ | 146 */ |
| 163 | 147 srtp_err_status_t srtp_rdbx_set_roc(srtp_rdbx_t *rdbx, uint32_t roc); |
| 164 err_status_t | |
| 165 rdbx_set_roc(rdbx_t *rdbx, uint32_t roc); | |
| 166 | 148 |
| 167 /* | 149 /* |
| 168 * rdbx_get_roc(rdbx) returns the value of the rollover counter for | 150 * srtp_rdbx_get_roc(rdbx) returns the value of the rollover counter for |
| 169 * the rdbx_t pointed to by rdbx | 151 * the srtp_rdbx_t pointed to by rdbx |
| 170 * | 152 * |
| 171 */ | 153 */ |
| 172 | 154 srtp_xtd_seq_num_t srtp_rdbx_get_packet_index(const srtp_rdbx_t *rdbx); |
| 173 xtd_seq_num_t | |
| 174 rdbx_get_packet_index(const rdbx_t *rdbx); | |
| 175 | 155 |
| 176 /* | 156 /* |
| 177 * xtd_seq_num_t functions - these are *internal* functions of rdbx, and | 157 * srtp_xtd_seq_num_t functions - these are *internal* functions of rdbx, and |
| 178 * shouldn't be used to manipulate rdbx internal values. use the rdbx | 158 * shouldn't be used to manipulate rdbx internal values. use the rdbx |
| 179 * api instead! | 159 * api instead! |
| 180 */ | 160 */ |
| 181 | 161 |
| 182 /* | 162 /* |
| 183 * rdbx_get_ws(rdbx_ptr) | 163 * srtp_rdbx_get_ws(rdbx_ptr) |
| 184 * | 164 * |
| 185 * gets the window size which was used to initialize the rdbx | 165 * gets the window size which was used to initialize the rdbx |
| 186 */ | 166 */ |
| 187 | 167 unsigned long srtp_rdbx_get_window_size(const srtp_rdbx_t *rdbx); |
| 188 unsigned long | |
| 189 rdbx_get_window_size(const rdbx_t *rdbx); | |
| 190 | 168 |
| 191 | 169 |
| 192 /* index_init(&pi) initializes a packet index pi (sets it to zero) */ | 170 /* index_init(&pi) initializes a packet index pi (sets it to zero) */ |
| 193 | 171 void srtp_index_init(srtp_xtd_seq_num_t *pi); |
| 194 void | |
| 195 index_init(xtd_seq_num_t *pi); | |
| 196 | 172 |
| 197 /* index_advance(&pi, s) advances a xtd_seq_num_t forward by s */ | 173 /* index_advance(&pi, s) advances a xtd_seq_num_t forward by s */ |
| 198 | 174 void srtp_index_advance(srtp_xtd_seq_num_t *pi, srtp_sequence_number_t s); |
| 199 void | |
| 200 index_advance(xtd_seq_num_t *pi, sequence_number_t s); | |
| 201 | 175 |
| 202 | 176 |
| 203 /* | 177 /* |
| 204 * index_guess(local, guess, s) | 178 * srtp_index_guess(local, guess, s) |
| 205 * | 179 * |
| 206 * given a xtd_seq_num_t local (which represents the highest | 180 * given a srtp_xtd_seq_num_t local (which represents the highest |
| 207 * known-to-be-good index) and a sequence number s (from a newly | 181 * known-to-be-good index) and a sequence number s (from a newly |
| 208 * arrived packet), sets the contents of *guess to contain the best | 182 * arrived packet), sets the contents of *guess to contain the best |
| 209 * guess of the packet index to which s corresponds, and returns the | 183 * guess of the packet index to which s corresponds, and returns the |
| 210 * difference between *guess and *local | 184 * difference between *guess and *local |
| 211 */ | 185 */ |
| 212 | 186 int srtp_index_guess(const srtp_xtd_seq_num_t *local, srtp_xtd_seq_num_t *guess,
srtp_sequence_number_t s); |
| 213 int | |
| 214 index_guess(const xtd_seq_num_t *local, | |
| 215 » » xtd_seq_num_t *guess, | |
| 216 » » sequence_number_t s); | |
| 217 | 187 |
| 218 | 188 |
| 189 #ifdef __cplusplus |
| 190 } |
| 191 #endif |
| 192 |
| 219 #endif /* RDBX_H */ | 193 #endif /* RDBX_H */ |
| 220 | |
| 221 | |
| 222 | |
| 223 | |
| 224 | |
| 225 | |
| 226 | |
| 227 | |
| 228 | |
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